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  • Articles: DFG German National Licenses  (216)
  • 2000-2004  (216)
  • 1890-1899
  • 2000  (216)
  • breast cancer  (140)
  • evolution  (76)
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  • Articles: DFG German National Licenses  (216)
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  • 2000-2004  (216)
  • 1890-1899
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  • 2000  (216)
  • 1
    ISSN: 1436-2813
    Keywords: Key Words: genetic changes ; prognostic factor ; breast cancer ; amplification ; loss of heterozygosity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: ERBB2 , INT2, and MYC genes, in 131 patients with breast carcinoma, 49 of whom had lymph node involvement, but none of whom had distant metastases. Among the several chromosome arms tested, LOH at 17q was correlated with lymph node metastasis. Amplification of the ERBB2, MYC, and INT2 genes was found more frequently in tumors from patients with lymph node metastases than in tumors from those without lymph node metastases. Univariate analysis demonstrated that LOH at 17q and INT2 amplification were factors influencing disease-free survival (DFS). A multivariate analysis was performed on 89 tumors that were able to be evaluated for both LOH at 17q and INT2 amplification, and the results showed that patients who had tumors with these genetic changes were more likely to have a poor prognosis. The findings of this study suggest that investigating genetic changes, in addition to conventional clinicopathologic factors, may contribute to defining groups of breast cancer patients with differences in prognosis.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Journal of ornithology 141 (2000), S. 263-274 
    ISSN: 1439-0361
    Keywords: Systematics ; evolution ; anagenesis ; genealogy ; reference system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Verglichen mit anderen Tiergruppen, scheint die artliche Bestandsaufnahme der rezenten Vögel nahezu abgeschlossen zu sein. Doch ist das System der Vögel weiterhin umstritten und mit vielen Neuerungen konfrontiert. Die Gründe dafür liegen hauptsächlich in neuen, vor allem molekularbiologischen Methoden und in den unerwartet reichen Fossilfunden der jüngsten Zeit. Als Beispiele werden Altgaumenvögel, Kranichvögel, Ibisse, Flamingos, Mausvögel, Hopfe und Sperlingsvögel kurz behandelt. Die hier erzielten Fortschritte lassen die Befürchtung Stresemanns, die Großsystematik der Vögel sei mit den vorhandenen Methoden phylogenetisch nicht interpretierbar, zunächst als unbergründet erscheinen. Doch erwachsen einer solchen Interpretation andere Hindernisse, deren Bedeutung bisher zu wenig beachtet wurde, nämlich Parallelentwicklungen, die viel verbreiteter sind als gemeinhin angenommen. Ihre Häufigkeit lässt sich sogar mit evolutionsbiologischen Argumenten begründen. Es ist deshalb nicht zu erwarten, dass die Diskussionen um das „richtige“ System bald verstummen. Um dennoch die Eindeutigkeit der Information in nicht-systematischen Veröffentlichungen zu wahren, wird empfohlen ein etabliertes Referenzsystem auf Zeit zu wählen.
    Notes: Summary Unlike in most animal classes the inventory of extant species of the class Aves seems to be almost complete. Nevertheless avian systematics is challenged by many novelties and seems far from being settled. This is caused mainly by the application of novel methods of molecular analysis to phylogenetic problems and by the unexpectedly rich fossil record collected within the last 10–20 years. Examples from the Palaeognathae, Gruiformes, Threskiornithidae, Phoenicopteridae, Coliiformes, Upupiformes and Passeriformes are briefly treated. The progress in the field seems to disprove Stresemann's pessimistic view that the phylogeny of higher categories (orders) cannot be reconstructed by the available methods. However, phylogenetic interpretations are impeded by obstacles not considered by Stresemann and highly underestimated in most cases, namely by multiple independent developments leading to identical features. Frequent parallel developments are to be expected for theoretical evolutionary reasons. The diagnosis of such homoplasies can be extremely difficult or even impossible. Therefore we cannot expect the discussion about the “best” system of birds to end in the near future. Considering this dynamic situation in systematics, it is recommended to maintain unambiguousness of information in not strictly systematic publications by refering to a well established system as a temporally limited reference.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Acta biotheoretica 48 (2000), S. 137-147 
    ISSN: 1572-8358
    Keywords: Sex ; sexual selection ; mate selection ; evolution ; ploidy ; assortative mating ; recombination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Using computer simulations I studied the simultaneous effect of variable environments, mutation rates, ploidy, number of loci subject to evolution and random and assortative mating on various reproductive systems. The simulations showed that mutants for sex and recombination are evolutionarily stable, displacing alleles for monosexuality in diploid populations mating assortatively under variable selection pressure. Assortative mating reduced excessive allelic variance induced by recombination and sex, especially among diploids. Results suggest a novel adaptive value for sex and recombination. They show that the adaptive value of diploidy and that of the segregation of sexes is different to that of sex and recombination. The results suggest that the emergence of sex had to be preceded by the emergence of diploid monosexual organisms and provide an explanation for the emergence and maintenance of sex among diploids and for the scarcity of sex among haploid organisms.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 97 (2000), S. 237-249 
    ISSN: 1570-7458
    Keywords: herbivores ; predators ; parasitoids ; mutualism ; induced defence ; behaviour ; ecology ; evolution ; sensory physiology ; plant fitness ; pathogens
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Herbivorous and carnivorous arthropods use plant volatiles when foraging for food. In response to herbivory, plants emit a blend that may be quantitatively and qualitatively different from the blend emitted when intact. This induced volatile blend alters the interactions of the plant with its environment. We review recent developments regarding the induction mechanism as well as the ecological consequences in a multitrophic and evolutionary context. It has been well established that carnivores (predators and parasitoids) are attracted by the volatiles induced by their herbivorous victims. This concerns an active plant response. In the case of attraction of predators, this is likely to result in a fitness benefit to the plant, because through consumption a predator removes the herbivores from the plant. However, the benefit to the plant is less clear when parasitoids are attracted, because parasitisation does usually not result in an instantaneous or in a complete termination of consumption by the herbivore. Recently, empirical evidence has been obtained that shows that the plant's response can increase plant fitness, in terms of seed production, due to a reduced consumption rate of parasitized herbivores. However, apart from a benefit from attracting carnivores, the induced volatiles can have a serious cost because there is an increasing number of studies that show that herbivores can be attracted. However, this does not necessarily result in settlement of the herbivores on the emitting plant. The presence of cues from herbivores and/or carnivores that indicate that the plant is a competitor- and/or enemy-dense space, may lead to an avoidance response. Thus, the benefit of emission of induced volatiles is likely to depend on the prevailing faunal composition. Whether plants can adjust their response and influence the emission of the induced volatiles, taking the prevalent environmental conditions into account, is an interesting question that needs to be addressed. The induced volatiles may also affect interactions of the emitting plant with its neighbours, e.g., through altered competitive ability or by the neighbour exploiting the emitted information. Major questions to be addressed in this research field comprise mechanistic aspects, such as the identification of the minimally effective blend of volatiles that explains the attraction of carnivores to herbivore-infested plants, and evolutionary aspects such as the fitness consequences of induced volatiles. The elucidation of mechanistic aspects is important for addressing ecological and evolutionary questions. For instance, an important tool to address ecological and evolutionary aspects would be to have plant pairs that differ in only a single trait. Such plants are likely to become available in the near future as a result of mechanistic studies on signal-transduction pathways and an increased interest in molecular genetics.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 95 (2000), S. 141-149 
    ISSN: 1570-7458
    Keywords: ecology ; reproductive success ; fecundity ; intraspecific competition ; evolution ; pest outbreaks ; pest control ; chemical control ; economic threshold ; oilseed rape ; turnip rape
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Populations of the rapeseed pollen beetle Meligethes aeneus F. (Col., Nitidulidae) from areas with 0–16 years of history of intensive rapeseed growing were compared for key ecological characters. During the first 16 years of rapeseed cultivation the reproductive success of M. aeneus increased 200–300% over that of the beetles living on the natural host plants, cruciferous weeds. The increase was linear over time and statistically highly significant, and it did not appear to be related to food quality or to the size of the beetles. During the same period the tolerance to intraspecific competition decreased, possibly due to the relative absence of such competition on the new crop. Furthermore, the optimum population density for M. aeneus to maximize the size of its next generation on summer turnip rape was determined to be 0.5–1.0 beetles/plant, which is slightly below the economic threshold for chemical control (1 beetle/plant). Therefore the practical protection of the rapeseed yield also ensures the highest possible pest population size for the next year. These mechanisms may in part explain the particular noxiousness of the species as a pest all over Europe. In general these data show that after the introduction of a new crop plant into a region, significant changes during the recruitment process in a pestiferous insect may take place, contributing to the future pest status of the insect. It is suggested that such genetic and ecological changes in insects may be a more common mechanism than previously thought in initiating and sustaining pest outbreaks, and that conventional pest management methods may enhance that effect.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Journal of insect behavior 13 (2000), S. 71-86 
    ISSN: 1572-8889
    Keywords: copulatory courtship ; behavioral interactions ; songs ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract D. birchii and D. serrata, two endemic Australian Drosophila species, have a copulatory courtship. The males of these species begin to court the female after mounting her and often go on with the courtship after the copulation is over. In the present paper we have described behavioral interactions between the male and the female and analyzed acoustic signals produced by the flies during courtship. Species differences were more pronounced in female than in male behavior. Variation within the species was obvious in the relative proportions of time the flies spent in different behaviors. Even though courtship took place nearly solely during copulation, some remains of precopulatory courtship were observed in both species. It is suggested that copulatory courtship exhibited by D. birchii and D. serrata flies is a derived rather than a primitive character.
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  • 7
    ISSN: 1572-9028
    Keywords: rutile supported V2O5–WO3 catalyst ; evolution ; NO reduction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract This paper concerns the relation between surface structure of crystalline vanadia-like active species on vanadia–tungsta catalyst and their activity in the selective reduction of NO by ammonia to nitrogen. The investigations were performed for Ti–Sn-rutile-supported isopropoxy-derived catalyst. The SCR activity and surface species structure were determined for the freshly prepared catalyst, for the catalyst previously used in NO reduction by ammonia (320 ppm NO, 335 ppm NH3 and 2.35 vol% O2) at 573 K as well as for the catalyst previously annealed at 573 K in helium stream containing 2.35 vol% O2. The crystalline islands, exposing main V2O5 surface, with some tungsten atoms substituted for V-ones, were found, with XPS and FT Raman spectroscopy, to be present at the surface of the freshly prepared catalyst. A profound evolution of the active species during the catalyst use at 573 K was observed. Dissociative water adsorption on V5+OW6+ sites is discussed as mainly responsible for the catalyst activity at 473 K and that on both V5+OW6+ and V4+OW6+ sites as determining the activity at 523 K.
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  • 8
    ISSN: 1569-8041
    Keywords: BRCA1 ; breast cancer ; p53 ; survival
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:The association between BRCA1 germ-linemutations and breast cancer prognosis is controversial. A historical cohortstudy was designed to determine the prognosis for women with axillary lymphnode negative hereditary breast cancer. Patients and methods:We tested pathology blocks from 118Ashkenazi Jewish women with axillary lymph node negative breast cancer for thepresence of the two common BRCA1 founder mutations, 185delAG and5382insC. Patients were followed up for a median of 76 months. SomaticTP53mutations were screened for by immunohistochemistry, and directsequencing was performed in the BRCA1-positive tumours. Results:Sixteen breast cancer blocks (13.6%) carried aBRCA1 mutation. Young age of onset, high nuclear grade, negativeestrogen receptor status and over-expression of p53 were highly associatedwith BRCA1-positive status (P-values all 〈0.01).BRCA1 mutation carriers had a higher mortality than non-carriers(five-year overall survival, 50% and 89.6%, respectively,P = 0.0001). Young age of onset, estrogen receptor negative status,nuclear grade 3, and over-expression of p53 also predicted a poor outcome. Coxmultivariate analyses showed that only germ-line BRCA1 mutationstatus was an independent prognostic factor for overall survival (P= 0.01). Among nuclear grade 3 tumours, the BRCA1 mutation carrierstatus was a significant prognostic factor of death (risk ratio 5.8,95% confidence interval: 1.5–22, P = 0.009). Sequencingof BRCA1-related breast cancers revealed one TP53missensemutation not previously reported in breast cancer. Conclusions:Using a historical cohort approach, we haveidentified BRCA1 mutation status as an independent prognostic factorfor node negative breast cancer among the Ashkenazi Jewish women. Thosemanaging women carrying a BRCA1 mutation may need take these findingsinto consideration. Additionally, our preliminary results, taken together withthe work of others suggest a different carcinogenic pathway inBRCA1-related breast cancer, compared to non-hereditary cases.
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  • 9
    ISSN: 1569-8041
    Keywords: BCL-2 ; breast cancer ; HER-2 ; p53 ; predictive factor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:The selection of therapies for breast cancer is todaybased on prognostic features (chemotherapy, radiotherapy), hormone receptorstatus (hormonal therapy) and HER-2 status (trastuzumab therapy). HER-2,p53and BCL-2are tumour-related proteins that have thepotential to further improve individualisation of patient management, bypredicting response to chemotherapy, hormonal therapy and radiotherapy. Materials and methods:This paper reviews the rationale for theuse of these proteins as predictive factors, as well as the publishedliterature addressing the use of each one to predict response to hormonaltherapy, chemotherapy and radiotherapy. Results:HER-2, p53and BCL-2remaininadequately assessed as predictive factors in breast cancer. HER-2 evaluationis required for the selection of patients for trastuzumab (Herceptin®)therapy, as trials of this therapy have been limited to HER-2 overexpressors.HER-2 overexpression may be predictive of resistance to hormonal therapy.Anthracyclines are effective therapy for breast cancer regardless of HER-2status, but patients whose tumours overexpress HER-2 appear to receive thegreatest relative benefit from this therapy. Studies of HER-2 as a predictorof response to CMF and to radiotherapy are inconclusive at this time. No datayet exist to support the use of p53or BCL-2as predictivefactors in the therapy of breast cancer. Conclusions:At this point in time, there is inadequate evidenceto support the use of HER-2, p53or BCL-2to guide theselection of hormonal therapy, chemotherapy or radiotherapy for breast cancer.
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  • 10
    ISSN: 1569-8041
    Keywords: breast cancer ; camptothecins ; colorectal cancer ; GI147211 ; non-small-cell lung cancer ; topoisomerase I
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:GI147211 is a water-soluble synthetic analogue ofcamptothecin showing promising in vivoand in vitroantitumor activity and an acceptable toxicity profile. Patients and methods:Between April 1995 and November 1996, 67eligible patients with pretreated breast cancer (25 patients) andchemo-naïve colorectal (19 patients) and non-small-cell lung cancer (23patients) were entered into three multicentric, non-randomized phase IItrials. Treatment schedule consisted of intravenous GI147211 administered ata dose of 1.2 mg/m2/day for five consecutive days every threeweeks. Results:Hematological toxicity was common with grade 3–4neutropenia in 54% of patients and neutropenic fever together or notassociated with infection in 14.5% of patients. Grade 3–4thrombocytopenia and grade 2–4 anemia were observed in 20% andin 68% of patients, respectively. Non-hematological toxicity wasgenerally mild to moderate and consisted mainly of gastrointestinal toxicity,asthenia and alopecia. A dose-escalation to 1.5 mg/m2/d wasfeasible in 17 (25%) patients. The antitumor activity of GI147211 wasmoderate in breast cancer patients (3 partial responses (PRs), response rate(RR) 13%) and minimal in non-small cell lung cancer patients (2 PRs,RR 9%). No objective responses were obtained in colorectal patients. Conclusions:GI147211, at the dose and schedule employed in thisstudy, showed an acceptable safety profile but a modest antitumor activity inthe examined tumor types.
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Biomedical microdevices 2 (2000), S. 305-316 
    ISSN: 1572-8781
    Keywords: membranes ; breast cancer ; oncology ; cell column regulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Using microfabrication technology, we have developed a new experimental apparatus and technique which allow isolation of individual cells and which facilitate the study of kinetic volume changes and membrane permeability. The key component of the apparatus is a microdiffusion chamber which was constructed using silicon microfabrication technology and standard photolithography. The central unit of the chamber is a 1 μ m thick silicon nitride membrane with a center hole on the order of 2–3 μ m in diameter. The device is novel in its analysis of a single cell, instead of the traditional array of cells, and its avoidance of the damage artifacts and computational difficulties which are inherent in other, commonly used methods of cellular analysis. The device is used in conjunction with a predictive computer model which simulates the response of the entire membrane or a portion of the membrane to various permeant and impermeant concentrations. This study introduces the apparatus and the model, and illustrates the effectiveness of the new procedure by determining several membrane permeability coefficients for HBL-100 (healthy human breast line). The empirical data and theoretical data were combined to yield a water permability (L p) of 1.1 ± 0.5μ m/(min-atm) (mean ± 1 standard deviation) (N= 5) during the uncoupled transport of water at 22 ±C. In the presence of 6 M glycerol, the water permeability (L p), permeability coefficient (P S), and the reflection coefficient (σS) were determined to be 2.0 ± 0.63 μ m/(min-atm), 2.7E-5 ± 6.1E-6 cm-sec-1, and 0.76 ± 0.5 (N = 6). No previous values of these coefficients could be found for HBL-100 cells.
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Foundations of science 5 (2000), S. 429-456 
    ISSN: 1572-8471
    Keywords: awareness ; reflexive awareness and consciousness ; evolution ; experience and pattern matching ; symbolic language
    Source: Springer Online Journal Archives 1860-2000
    Topics: Natural Sciences in General
    Notes: Abstract An evolutionary point of view is proposed to make more appropriate distinctions between experience, awareness and consciousness. Experience can be defined as a characteristic linked closely to specific pattern matching, a characteristic already apparent at the molecular level at least. Awareness can be regarded as the special experience of one or more central, final modules in the animal neuronal brain. Awareness is what experience is to animals. Finally, consciousness could be defined as reflexive awareness. The ability for reflexive awareness is distinctly different from animal and human awareness and depends upon the availability of a separate frame of reference, as provided by symbolic language. As such, words have made reflexive awareness – a specific and infrequent form of awareness – possible. Conciousness might be defined as the experience evoked by considering, i.e. thinking about experiences themselves. If there is a hard problem of explaining consciousness, than this actually must be considered as the hard problem already met when trying to explain basic experience, since its nature remains elusive.
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  • 13
    ISSN: 1569-8041
    Keywords: biological/pathological characteristics ; breast cancer ; prognosis ; progression ; symptomatic/asymptomatic patients
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:It is well known that mammographic screening reducesbreast cancer mortality. One possible explanation for this effect is thatscreening makes it possible to detect smaller breast cancers with fewerinvolved nodes, but another hypothesis is that some screening-detected tumorsare in a pathologically and biologically different phase of evolution fromthose that are detected clinically. The aim of the present study was tocompare the biological, pathological and clinical characteristics ofsymptomatic vs. asymptomatic breast cancers. Patients and methods:The study considers a series of 1916consecutive patients who underwent surgery for stage I and II infiltratingbreast cancer at Verona hospitals after having undergone ultrasound andmammography (at least one of which was positive). They were divided into twogroups on the basis of why they decided to undergo the imaging examinations:group A refers to the 1247 patients with a palpable lump, and group B to the616 who were asymptomatic. Results:The patients in group A were older, and had larger tumorsand a higher percentage of positive nodes than those in group B; they also hadsignificantly higher grade tumors, higher Ki-67 levels, and a higherpercentage of ER and PgR negative and c-erbB-2 positive tumors (allof the P-values were significant). A logistic regression analysisadjusted for tumor diameter and age showed a reduction in the significance ofeach of the considered variables, but all of them remained significantlyassociated with the modality of diagnosis except ER, PgR andc-erbB-2. Conclusions:Our results suggest that asymptomatic tumors arebiologically different from their clinically presenting counterparts, thusconfirming the hypothesis that progression towards greater malignancy mayoccur during the natural history of breast cancer.
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  • 14
    ISSN: 1569-8041
    Keywords: 4-OH-IF ; breast cancer ; drug combination ; human cell lines ; primary cultures ; VNB
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:Vinorelbine and ifosfamide are active drugs againstbreast cancer, but the best treatment schedule has yet to be defined bypreclinical or clinical studies. The antitumor activity of4-hydroxy-ifosfamide (4-OH-IF), the active form of ifosfamide, and vinorelbine(VNB) and their interaction were investigated in two established breast cancercell lines (MCF-7 and BRC-230) and in 10 primary breast cancer cultures. Materials and methods:Cytotoxic activity was evaluated by ahighly efficient clonogenic assay (HECA). The median-effect principle wasapplied to evaluate synergistic and antagonistic interactions and thecorresponding combination index values were calculated. Cell cycleperturbations were analysed by flow cytometry. Results:In MCF-7 and BRC-230 cell lines the sequence VNB for 4hours followed by 4-OH-IF for 24 hours produced an antagonistic effect.Conversely, the inverse sequential scheme, 4-OH-IF → VNB providedsynergistic effects on both cell lines. The synergism was associated with astrong block in the G2-M phase. Synergistic activity of 4-OH-IF → VNBsequence was confirmed in 7 of 10 primary breast cancercultures. Conclusions:In conclusion, the sequence 4-OH-IF → VNBappeared to be the most effective scheme both in established cell lines andin primary breast cancer cultures.
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  • 15
    ISSN: 1569-8041
    Keywords: adjuvant treatment ; breast cancer ; tamoxifen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Aim:Immediate adjuvant tamoxifen reduces disease recurrence andimproves survival in patients with early breast cancer. However, is it toolate to administer tamoxifen to patients who have already undergone treatment,but were unable to benefit from this adjuvant therapy? The French NationalCancer Centers (FNCLCC) have investigated the efficacy of delayed tamoxifenadministration in a randomized controlled trial. Patients and methods:From September 1986 to October 1989, womenwith primary breast cancer, who had undergone surgery, radiotherapy, and/orreceived adjuvant chemotherapy but not hormone therapy more than two yearsearlier, were randomized to receive either 30 mg/day tamoxifen or notreatment. The 10-year disease-free and overall survival rates of the twogroups of patients and of various subgroups were determined according to theKaplan–Meyer method and compared by the log-rank test. Results:This intention-to-treat analysis comprised 250 women inthe tamoxifen group and 244 in the control group. Patient characteristics(age, T stage, number of positive nodes, receptor status, and interval sincetumor treatment) were comparable in both groups. Delayed adjuvant tamoxifensignificantly improved overall survival only in node-positive patients and inpatients with estrogen receptor-positive (ER+) or progesteronereceptor-positive (PR+) tumors. Disease-free survival, however, wassignificantly improved in the global population and in several patientsubgroups (node-positive, ER+, PR+). Patients in whom the interval betweenprimary treatment and delayed adjuvant tamoxifen was greater than five yearsalso had significantly improved disease-free survival. Conclusions:Overall and disease-free survival results indicatethat delayed adjuvant tamoxifen administration (30 mg/day) is justified inwomen with early breast cancer, even if this treatment is initiated two ormore years after primary treatment.
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  • 16
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    Springer
    Annals of oncology 11 (2000), S. 1349-1351 
    ISSN: 1569-8041
    Keywords: breast cancer ; radiotherapy ; tumor lysis syndrome
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Tumor lysis syndrome (TLS) is a rare serious acute complication of cancertherapy, reported mainly following chemotherapy in patients with large tumorload and chemosensitive disease. These are mainly patients with non-Hodgkin'slymphoma, leukemia and rarely in solid tumors. It is less frequently describedafter radiotherapy for lymphoid and hematological malignancies. TLS followingradiotherapy for solid tumors is a very rare complication. In thisreport/review we describe a seventy-three-year-old male patient withprogressive metastatic carcinoma of the breast to the lungs, liver and bone.He was referred for radiotherapy because of generalized bony pains. Thepatient was planned for sequential hemi-body irradiation starting with themore symptomatic upper half body. After premedication, he was given 8.5 Gy tothe mid point at the maximum chest separation with anterior lung attenuatorlimiting uncorrected lung dose to 6.15 Gy. A further 3.5 Gy electron boost tothe fungating breast tumor was given to the 100%. Forty-eight hours after irradiation he developed hyperkalemia,hyperphosphatemia, hyperuricemia, hypocalcemia and renal failure. Theseclinical and biochemical changes are typical of tumor lysis syndrome (TLS).Despite hydration, and treating the hyperuricemia, the patient developed comaand died eight days after irradiation. The prophylaxis and management of TLS and in high-risk patients aredescribed to avoid this frequently fatal complication.
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  • 17
    ISSN: 1569-8041
    Keywords: breast cancer ; erbB2 ; HER-2/neu ; tamoxifen ; therapy resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Aim:We aimed to study the importance of erbB2 status in earlystage postmenopausal breast cancer for patients who participated in a trialof five vs. two years of adjuvant tamoxifen. Patients and methods:We analysed the erbB2 status of the tumoursfrom 577 patients participating in the trial, either by a DNA amplificationassay (n = 181) or by measurement of the protein level with flowcytometry (n = 396). Results:ErbB2 was overexpressed or gene amplified in 102 of thepatients (18%). Overall, erbB2-positive patients had a significantlylower recurrence-free probability than others, 62% at five years ascompared to 83%, and showed a significantly decreased breast cancersurvival rate (P = 0.0007). ErbB2 status was significantlyassociated with recurrence and death in Cox multivariate analysis, adjustingfor nodal status, tumour size and estrogen receptor status. The relative riskof recurrence (RR) for five vs. two years of tamoxifen was analysed inrelation to erbB2 status for patients still disease-free two years aftersurgery. Whereas erbB2-negative patients showed significant benefit fromprolonged treatment (RR = 0.62, 95% confidence interval (95%CI): 0.42–0.93), no benefit was evident for erbB2-positive patients (RR= 1.1, 95% CI: 0.41–3.2). When the same analysis was restrictedto ER-positive patients a similar difference in relative hazard was obtainedbut the difference was not strictly significant (P = 0.065). Conclusions:For early stage breast cancer patients treated withadjuvant tamoxifen, overexpression of erbB2 is an independent marker of poorprognosis. The results suggest that overexpression decreases the benefit fromprolonged tamoxifen treatment.
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  • 18
    ISSN: 1569-8041
    Keywords: breast cancer ; cyclophosphamide ; elderly ; idarubicin ; oral chemotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 19
    ISSN: 1569-8041
    Keywords: adjuvant therapy ; breast cancer ; docetaxel ; feasibility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background and purpose:Docetaxel is an active agent in thetreatment of metastatic breast cancer. We evaluated the feasibility ofdocetaxel-based sequential and combination regimens as adjuvant therapies forpatients with node-positive breast cancer. Patients and methods:Three consecutive groups of patients withnode-positive breast cancer or locally-advanced disease, aged ≤70 years,received one of the following regimens: a) sequential A → T → CMF:doxorubicin 75 mg/m2 q 3 weeks × 3, followed by docetaxel 100mg/m2 q 3 weeks × 3, followed by i.v. CMF days 1 + 8 q 4weeks × 3; b) sequential accelerated A → T → CMF: A and T wereadministered at the same doses q 2 weeks; c) combination therapy: doxorubicin50 mg/m2 + docetaxel 75 mg/m2 q 3 weeks × 4,followed by CMF × 4. When indicated, radiotherapy was administeredduring or after CMF, and tamoxifen started after the end of CMF. Results:Seventy-nine patients have been treated. Median age was48 years. A 30% rate of early treatment discontinuation was observedin patients receiving the sequential accelerated therapy (23% duringA → T), due principally to severe skin toxicity. Median relativedose-intensity was 100% in the three treatment arms. The incidence ofG3–G4 major toxicities by treated patients, was as follows: skintoxicity a: 5%; b: 27%; c: 0%; stomatitis a: 20%;b: 20%; c: 3%. The incidence of neutropenic fever was a:30%; b: 13%; c: 48%. After a median follow-up of 18months, no late toxicity has been reported. Conclusions:The accelerated sequential A → T → CMFtreatment is not feasible due to an excess of skin toxicity. The sequentialnon accelerated and the combination regimens are feasible and under evaluationin a phase III trial of adjuvant therapy.
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  • 20
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    Journal for general philosophy of science 31 (2000), S. 57-73 
    ISSN: 1572-8587
    Keywords: complex systems ; evolution ; nonlinearity ; pre-determination ; self-organization ; soft management ; structure-attractors ; synergetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Philosophy , Nature of Science, Research, Systems of Higher Education, Museum Science
    Notes: Abstract The philosophical consequences of synergetics, the interdisciplinary theory of evolution and self-organization of complex systems, are being drawn in the paper. The idea of discreteness of evolutionary paths is in the focus of attention. Although the future is open, and there are many alternative evolutionary paths for complex systems, not any arbitrary (either conceivable or desirable) evolutionary path is feasible in a given system. There are discrete spectra of possible evolutionary paths which are determined exclusively by inner properties of the corresponding systems. Synergetics allows us to reveal general laws of self-organization and, therefore, certain limits of arbitrariness of nature in choosing possible paths of evolution as well as in constructing of a complex evolutionary whole. A comparative analysis between the modern synergetic notions and a few ideas of the Western philosophy (F. Nietzsche, N. Hartmann, M. Heidegger) and of the Eastern teachings (Taoism, Buddhism) is made.
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  • 21
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    International journal of value-based management 13 (2000), S. 297-308 
    ISSN: 1572-8528
    Keywords: morality ; moral systems ; behavior ; evolution ; adaptation ; natural selection ; altruism ; reciprocal altruism ; fitness ; reciprocity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Economics
    Notes: Abstract The ethical and moral behavior of Homo sapiens is no longer the exclusive domain of religion and philosophy because we recognize that such behavior affects the reproductive success of individuals within the species. We are a social species and therefore our survival is influenced by our capacity for cooperation and our willingness to take risks for kin. Emotions, some of which are found in other species, help to mediate our altruistic behavior. The reproductive benefits of helping kin, especially offspring, are readily seen. Helping non-kin can be beneficial if individuals can differentiate between ‘reciprocators’ and ‘non-reciprocators’ and direct altruistic behavior toward reciprocators. Also, if third parties are favorably impressed by observing altruistic behavior, the rewards need not come from the recipient of the altruistic behavior.
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  • 22
    ISSN: 1572-9737
    Keywords: conservation genetics ; Equus ; evolution ; mitochondrial DNA control region ; mitochondrial 12S rRNA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The evolution, taxonomy and conservation of the genus Equuswere investigated by examining the mitochondrial DNA sequences of thecontrol region and 12S rRNA gene. The phylogenetic analysis of thesesequences provides further evidence that the deepest node in thephylogeny of the extant species is a divergence between twolineages; one leading to the ancestor of modern horses (E.ferus, domestic and przewalskii) and the other to thezebra and ass ancestor, with the later speciation events of the zebrasand asses occurring either as one or more rapid radiations, or withextensive secondary contact after speciation. Examination of the geneticdiversity within species suggested that two of the E. hemionussubspecies (E. h. onager and E. h. kulan) onlyrecently diverged, and perhaps, are insufficiently different to beclassified as separate subspecies. The genetic divergence betweendomestic and wild forms of E. ferus (horse) and E.africanus (African ass) was no greater than expected within anequid species. In E. burchelli (plains zebra) there was anindication of mtDNA divergence between populations increasing withdistance. The implications of these results for equid conservation arediscussed and recommendations are made for conservation action.
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  • 23
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    Journal of the history of biology 33 (2000), S. 457-491 
    ISSN: 1573-0387
    Keywords: J. B. S. Haldane ; biology ; politics ; genetics ; evolution ; population genetics ; physiology ; Darwinism ; experimental biology ; eugenics ; Britain ; Russia ; India ; Soviet ; Communism ; socialism ; philosophy ; vision ; literature ; popularization ; religion ; human experimentation ; bioethics ; Venus ; Mars ; science fiction ; technocracy ; futurology ; H. G. Wells ; Julian Huxley ; Olaf Stapledon ; C. S. Lewis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , History
    Notes: Abstract This paper seeks to reinterpret the life and work of J. B. S. Haldane by focusing on an illuminating but largely ignored essay he published in1927, “The Last Judgment” – the sequel to his better known work, Daedalus (1924). This astonishing essay expresses a vision of the human future over the next 40,000,000 years, one that revises and updates Wellsian futurism with the long range implications of the “new biology” for human destiny. That vision served as a kind of lifelong credo, one that infused and informed his diverse scientific work, political activities, and popular writing, and that gave unity and coherence to his remarkable career.
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  • 24
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    Journal of the history of biology 33 (2000), S. 221-246 
    ISSN: 1573-0387
    Keywords: August Weismann ; ciliates ; Clifford Dobell ; cytology ; death ; Emile Maupas ; evolution ; Herbert Spencer Jennings ; Otto Bütschli ; Paramecium ; rejuvenescence ; sex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , History
    Notes: Abstract In the period 1875–1920, a debate about the generality and applicability of evolutionary theory to all organisms was motivated by work on unicellular ciliates like Paramecium because of their peculiar nuclear dualism and life cycles. The French cytologist Emile Maupas and the German zoologist August Weismann argued in the 1880s about the evolutionary origins and functions of sex (which in the ciliates is not linked to reproduction), and death (which appeared to be the inevitable fate of lineages denied sexual conjugation), an argument rooted in the question of whether the ciliates and their processes where homologous to other cellular organisms. In the beginning of the twentieth century, this question of homology came to be less important as the ciliates were used by the British protozoologist Clifford Dobell and the American zoologist Herbert Spencer Jennings to study evolutionary processes in general rather than problems of development and cytology. For them, homology mattered less than analogy. This story illustrates two partially distinct problems in evolutionary biology: first, the question of whether all living things have common features and origins; and second, whether their history and current nature can be described by identical mechanisms. Where Maupas (contra Weismann) made the ciliates qualitatively the same as all other organisms in order to create a cohesive evolutionary theory for biology, Jennings and Dobell made them qualitatively different in order to achieve the same end.
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  • 25
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    Anatomy and embryology 202 (2000), S. 281-290 
    ISSN: 1432-0568
    Keywords: Key words Extracellular matrix ; cartilage ; bone ; evolution ; lamprey ; agnathan
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Previous evidence from our laboratories showed that collagen is not the major matrix protein of the cartilaginous endoskeleton of the lamprey (Petromyzon marinus). Here we have characterized the cartilage matrix proteins of the only other extant agnathan, the hagfish (Myxine glutinosa). Using morphological, immunochemical and biochemical methods, we show that the structural proteins of the cartilaginous endoskeleton of the hagfish are also non-collagenous in nature. Although these hagfish cartilage proteins share properties both with each other and with lamprey cartilage proteins, including resistance to solubilization with cyanogen bromide and an usual amino acid composition rich in glycine and non-polar amino acids, it is clear that at least two and probably more hagfish cartilage proteins can be distinguished, with distinct distributions in different cartilage structures. Furthermore, in spite of their similarities, matrix proteins from hagfish cartilage are not identical to the proteins we have previously characterized in lamprey cartilage. These results suggest the existence of a larger family of similar but not identical proteins that form the major structural elements of cartilage tissues of agnathans. These data also support our previous conclusion that type II collagen became the predominant structural protein of cartilage only after the divergence of the agnathans from the ancestral line of the vertebrates.
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  • 26
    ISSN: 1569-8041
    Keywords: breast cancer ; combination therapy ; paclitaxel ; vinorelbine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose:To evaluate the anti-tumour activity and tolerance of thecombination of paclitaxel plus vinorelbine in metastatic breast cancer (MBC)patients previously treated with anthracyclines. Patients and methods:Fifty-six MBC patients who have had at leastone previous anthracycline-containing chemotherapy regimen were enrolled inthis phase II trial. Patients received paclitaxel (135 mg/m2 overone-hour infusion) and vinorelbine (30 mg/m2) both on day 1 of eachthree-week course of therapy (maximum eight courses or until diseaseprogression was evident). Results:Six complete and nineteen partial responses were observedamong the fifty-four assessable patients (response rate of 46%,95% CI: 33%–60%). Responses were observed in alldisease sites and in all subsets of patients. The response rates whenpaclitaxel plus vinorelbine were used as first, second and third-linechemotherapy for metastases were 67%, 41% and 35%,respectively. The response rate among anthracycline-refractory patients was46% (6 of 13). Median time to progression in the overall patient groupwas 28 weeks. The main toxicities (CTC grade 2 or more) were alopecia,myelosuppression and peripheral neuropathy (85%, 46% and19% of patients, respectively). Nine patients (17%) hadneutropenic fever in fifteen of the three hundred twenty-eight coursesadministered (5%). Conclusions:The combination of paclitaxel and vinorelbine on day1 every three weeks is active in MBC patients with prior anthracyclineexposure. The regimen is safe, well tolerated and convenient for the patients.
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  • 27
    ISSN: 1569-8041
    Keywords: breast cancer ; cyclophosphamide ; fluorouracil ; mitoxantrone ; radiation therapy ; secondary leukemia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:The topoisomerase II-targeted drugs,epipodophyllotoxins and anthracyclines, have been shown to inducetherapy-related AML (t-AML) characterized by a short latency period afterchemotherapy, the absence of prior myelodysplastic syndrome and stereotypedchromosome aberrations. Few reports have been published on patients treatedwith the anthracenedione mitoxantrone which also targets topoisomerase II. Weobserved 10 cases of such t-AML over a 7-year-period in breast cancer patientstreated with mitoxantrone combined with fluorouracil, cyclophosphamide andregional radiotherapy, and in three cases with vindesine. Patients and methods:We retrospectively analyzed patientsreferred to our hospital for AML with a past history of polychemotherapy forbreast cancer, including mitoxantrone, either as adjuvant (8patients)/neoadjuvant (1 patient) therapy or for metastatic disease (1patient). We studied the probability of developing t-AML in a prospectiveseries of 350 patients treated with an adjuvant FNC regimen (mitoxantrone,fluorouracil, cyclophosphamide) and radiation therapy. Results:The median age was 45 years (range 35–67). t-AMLdeveloped 13–36 months (median 16) after beginning chemotherapy forbreast cancer, and 4–28 months (median 10.5) after ending treatment. Asdescribed in t-AML following treatment with epipodophyllotoxins oranthracyclines, we found a majority of FAB M4, M5 and M3 phenotypes (7 of 10),and characteristic karyotype abnormalities that also can be found in denovoAML: breakpoint on chromosome 11q23 (3 patients), inv(16)(p13q22)(2 patients), t(15;17)(q22;q11) (1 patient), t(8;21)(q22;q22) (1 patient) anddel(20q)(q11) (1 patient). The prognosis was poor. All patients died of AMLshortly after diagnosis. Since two patients had been enrolled in a prospectivetrial for the treatment of breast cancer which included 350 patients, theprobability of developing t-AML was calculated to be 0.7% from25–40 months, using the Kaplan–Meier method (95% confidenceinterval (95% CI): 0.1–4.5). Conclusions:The combination of mitoxantrone withcyclophosphamide, fluorouracil, and radiation therapy can induce t-AML, aswith other topoisomerase II-targeted drugs. Despite a low incidence, theprognosis appears to be poor.
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  • 28
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    Annals of oncology 11 (2000), S. 1255-1262 
    ISSN: 1569-8041
    Keywords: age ≤35 years ; breast cancer ; single institution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:Early-onset breast cancer may differ with respect toetiology, clinical features and outcome compared with breast cancer in olderwomen. To gain further insight, we retrospectively reviewed the clinicalfeatures and outcome of women ≤35 years with primary breast cancer seen atour institution over a 30-year period. Patients and methods:Charts were reviewed for women with operablebreast cancer diagnosed ≤35 years of age seen at the Princess MargaretHospital (PMH), Toronto from 1965–1994. Results:One thousand eighty-six women with non-metastaticinvasive breast cancer, aged 18.3–35.6 years (median 32.1 years) werereferred to PMH. Symptoms at presentation included: self-detected breast lump(83%), other breast symptom (10%), physician diagnosis(4%) and unknown (3%). Tumor size was known in 936 (〉2 cm in61%) and nodal status in 888 (lymph node positive in 52%).Modified radical mastectomy was performed in 568 (57%) andbreast-conservation surgery (BCS) in 422 (42%). Five hundred sixteen(51%) patients received adjuvant radiotherapy and five hundredthirty-four (53%) adjuvant systemic therapy. Two hundred ninety-three(29%) patients had a family history of breast cancer (FH).Contralateral breast cancer (CBC) occurred more frequently in women with FH(Prange 0.042–0.008). Local recurrence (LR) was 37% and73% at 10 years in those treated by BCS with and without radiotherapy,respectively. At 10 years, disease-free survival (DFS) was 30% andoverall patient survival 48%. Conclusions:In this cohort, breast cancer was usuallyself-diagnosed and tumors were 〉2 cm at presentation in approximatelytwo-thirds of cases, suggesting the possibilities of a delay in diagnosis,more aggressive tumors or both. Our results are compatible with the knownassociation of breast cancer FH with increased CBC. Our data also corroboratesthe suggestion that positive genetic testing in this age group should lead toconsideration of more aggressive ipsilateral and contralateral breastmanagement. In those receiving adjuvant irradiation after BCS, the LR rate washigh, but did not impact on overall survival.
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  • 29
    ISSN: 1569-8041
    Keywords: breast cancer ; carboplatinum ; chemotherapy ; continuous 5-fluorouracil
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We performed a trial using the combination of epirubicin 50mg/m2/day 1, carboplatinum AUC 5/day 1 and continuous5-fluorouracil (5-FU) 200 mg/m2/day (every 4 weeks for6 months) to confirm the efficacy and low toxicity profile of thisregimen in breast cancer. In 51 patients with metastatic(n = 33) or locally advanced (n = 18)breast cancer the overall response rate was 86% (95% confidenceinterval (95% CI): 73%–94%): 94% in locallyadvanced and 81% metastatic disease. Grade 3–4 toxicity was low:4% of patients presented with febrile neutropenia, 16% withsevere palmar-plantar syndrome, 10% with Port-a-cath thrombosis. This study confirms the high efficacy of infusional 5-FU-based regimens andjustifies further research into novel promising oral 5-FU derivatives.
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  • 30
    ISSN: 1569-8041
    Keywords: adjuvant chemotherapy ; breast cancer ; doxorubicin ; elderly patients
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:The purpose of this study was to evaluate the clinicaloutcome of doxorubicin-based adjuvant chemotherapy in elderly breast cancerpatients and to compare results in elderly patients with those in youngerpatients. Patients and methods:We retrospectively reviewed the records ofall patients aged 50 years or older treated in trials of doxorubicin-basedadjuvant chemotherapy between 1974 and 1988. Old age was not an exclusioncriterion for these trials. Patient characteristics, hematologic andnonhematologic side effects, patterns of recurrence, and causes of death weredetermined for patients aged 50–64 years and for patients aged 65 yearsor older, and results were compared between these two groups.Kaplan–Meier survival curves were plotted, and tested by the generalizedWilcoxon test. Results:A total of 390 patients aged 50 years or older weretreated with doxorubicin-based adjuvant chemotherapy during the study period.Of these, 325 were aged 50–64 years (group 1), and 65 were aged 65 yearsor older (group 2). The median follow-up period for group 1 was 185 months(range 29–272+ months), and the median follow-up period for group 2 was169 months (range 128–240+ months). There were no statisticallysignificant differences between the two groups with respect to performancestatus, hormone receptor profile, tumor size, nodal status, or type oflocoregional therapy. There also were no statistically significant differencesbetween the two groups in recurrence patterns, disease-free survival, oroverall survival. The granulocyte and platelet nadirs of cycles 1, 3, and 6were similar between the two groups. No cumulative hematologic side effectswere seen in either group. The occurrence of second malignancies was extremelylow in both groups. In both groups, the majority of deaths were due toprogression of disease. Conclusions:Adjuvant doxorubicin-based chemotherapy is welltolerated in elderly breast cancer patients who have good performance statusand normal cardiac ejection fraction. Adjuvant doxorubicin-based chemotherapyin these patients results in disease-free and overall survival rates similarto those seen in younger patients.
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  • 31
    ISSN: 1569-8041
    Keywords: breast cancer ; hot flashes ; paroxetine ; serotonin uptake inhibitors ; survivors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:Many breast cancer survivors suffer debilitating hotflashes. Estrogen, the drug of choice in perimenopausal women, is generallynot recommenced to breast cancer survivors. Nonhormonal treatments are mostlydisappointing. Anecdotal reports in our institution suggested that theselective serotonin-reuptake inhibitor, paroxetine hydrochloride, might beefficacious in alleviating hot flashes. Patients and methods:Thirty women with prior breast cancer whowere suffering at least two hot flashes a day entered a single institutionpilot trial to evaluate paroxetine's efficacy in reducing the frequency andseverity of hot flashes. After completing daily diaries for one week on notherapy, the women received open-label paroxetine, 10 mg daily for one week,followed by four weeks of paroxetine, 20 mg daily. The women completedhot-flash daily diaries throughout the study period, and a health-relatedsymptom-assessment questionnaire and a quality-of-life rating scale in thefirst and sixth week of the study. Results:Twenty-seven women completed the six-week study period.The mean reduction of hot flash frequency was 67% (95%confidence interval (95% CI): 56%–79%). The meanreduction in hot flash severity score was 75% (95% CI:66%–85%). There was a statistically significantimprovement in depression, sleep, anxiety, and quality of life scores.Furthermore, 25 (83%) of the study participants chose to continueparoxetine therapy at the end of study. The most common adverse effect wassomnolence, resulting in drug discontinuation in two women, and dose reductionin two women. One woman discontinued drug due to anxiety. Conclusions:Paroxetine hydrochloride is a promising new treatmentfor hot flashes in breast cancer survivors, and warrants further evaluationin a double-blind randomized placebo-controlled trial.
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  • 32
    ISSN: 1569-8041
    Keywords: breast cancer ; socio-economic status ; stage
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:This study describes and compares the pathologicalprognostic factors and surgeon assessment of stage of breast cancer of womenliving in affluent and deprived areas to assess whether clinical stage atpresentation may explain the known poorer survival outcomes for deprivedwomen. Patients and methods:A population-based review of the caserecords of 417 women with breast cancer was carried out. Results:No difference in pathological criteria was found betweenthe 88% of women living in affluent and deprived areas for whom suchdata were available. Clinical assessment of the remaining 50 cases showed thatwomen living in deprived areas were more likely to present with locallyadvanced or metastatic disease. Conclusion:The poorer survival of women from deprived areas withbreast cancer may be explained by more deprived women presenting with advancedcancers.
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  • 33
    ISSN: 1569-8041
    Keywords: breast cancer ; choice ; decision-making process ; patient–physician relationship
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:Shared decision-making is increasingly advocated asan ideal model. However, very few studies have tested the feasibility ofgiving patients the opportunity to participate in the choice of treatment. Patients and methods:Women, with non-metastatic breast cancer,eligible for non-intensified adjuvant chemotherapy attending our hospital wereproposed two administrations of chemotherapy and radiotherapy: a sequentialand a concomitant one. Two patient-questionnaires were used to elicitmotivations for their choice and their degree of comfort with the process ofdecision-making and one questionnaire to test physicians' ability to predictpatients' choice. Results:Participation rate in the study was 75.3%(n = 64). Majority (64%) of patients chose the concomitanttreatment. Multivariate analysis revealed that patients with a lower level ofeducation, who discussed the choice with social circle, and who most fearedside-effects were more likely to choose the sequential treatment. Physicianswere able to predict patients' choice in 66% of cases. 89% ofpatients declared that they were "fully satisfied" with having participatedin the choice of treatment and 79% supported shared decision-making. Conclusions:Results are in favour of promoting activeparticipation of cancer-patients in medical decision-making. The adequatedegree of such participation remains however to be elicited and tested fortherapeutic choices implying more difficult trade-offs between quantity andquality of life.
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  • 34
    ISSN: 1569-8041
    Keywords: adjuvant therapy ; breast cancer ; second cancer ; tamoxifen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:Women treated with tamoxifen for breast cancer are atincreased risk of endometrial cancer. We conducted a retrospective cohortstudy to evaluate the risk of second primary cancers after adjuvant tamoxifentherapy for breast cancer in Japan. Patients and methods:The subjects of the study were 6148 womenwho had been diagnosed with stage I, II, or IIIA unilateral primary breastcancer and had received surgical treatment during the period from January 1982through December 1990 at nine institutions in Japan. The information on eachpatient was obtained from medical records or a prospectively compiled computerdatabase at each institution. Results:Of the 6148 women, 3588 (58.4%) were administeredtamoxifen as an adjuvant treatment and 2560 (41.6%) were notadministered. Median follow-up periods were 7.64 years for tamoxifen-treatedpatients and 8.10 years for non-tamoxifen-treated patients, respectively. Theduration of tamoxifen treatment was mostly two years or less (80.7%),and few patients received tamoxifen for more than five years. The cumulativeincidence rates of all second cancers at 10 years were 4.61% and4.09% among tamoxifen-treated and non-tamoxifen-treated patients(P = 0.62), respectively, and the incidence rate ratio (IRR) forall second cancers was 1.06 (95% confidence interval (CI):0.77–1.47) after adjustment of several covariates. The numbers ofendometrial cancers was 9 and 3 among tamoxifen-treated andnon-tamoxifen-treated patients, respectively, and the IRR was 2.37 (95%CI: 0.64–8.77, P = 0.20). Of the 12 patients who developedendometrial cancer, 4 died of cancer (for 3 of them, the cause of death wasbreast cancer), and the other 8 patients were alive as of March 1996. Stomachcancer was the most frequent second cancer and the IRR was 1.34 (95%CI: 0.76–2.38, P = 0.31). There was no substantialincrease in any other type of gastrointestinal cancer such as colorectal andliver cancers among tamoxifen-treated patients. Conclusions:The incidence and risk of second primary cancersassociated with tamoxifen therapy is low. The potential benefit of adjuvanttamoxifen therapy in breast cancer patients outweighs the risk of secondprimary cancers for Japanese breast cancer patients.
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  • 35
    ISSN: 1569-8041
    Keywords: breast cancer ; docetaxel ; epirubicin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose:In a previous phase I trial we evaluated the toxicity anddetermined the maximum tolerated doses of the docetaxel (D)–epirubicin(Epi) combination. We conducted a multicenter phase II study to evaluate theefficacy and tolerability of this regimen as front-line treatment in womenwith advanced breast cancer (ABC). Patients and methods:Fifty-four women with ABC stage IIIB (4patients) or IV (50 patients) received front-line treatment with Epi 70mg/m2 on day 1 and D 90 mg/m2 on day 2. The median agewas 55 years, performance status (WHO) was 0–1 in 49 patients andvisceral disease was present in 45 (83%). Results:All patients were evaluable for toxicity and 50 forresponse. In an intent-to-treat analysis complete remission was observed in5(9%) patients, partial remission in 31 (57%) (overall responserate 66%, 95% confidence interval: 54%–79%),stable disease in 9 (17%) and disease progression in 9 (17%).After a median follow-up of 11.5 months, the median duration of responses was8 months, the median time to disease progression 11.5 months and the mediansurvival has not yet been reached. The probability of one-year survival was65%. Three hundred six cycles of treatment were administered (median6 cycles per patient). Grade 3 and 4 neutropenia was observed in 8(15%) and 31 (57%) patients, respectively, and febrileneutropenia in 19 (35%). Prophylactic rh-G-CSF was used in 45(83%) patients or 226 (74%) cycles. Other hematologic ornon-hematologic toxicities were usually mild. In five (9%) patients theleft ventricular ejection fraction (LVEF) was decreased by more than10% with the treatment. Two patients died during the treatment ofrespiratory failure without associated neutropenia. Conclusions:The combination of docetaxel–epirubicin is aneffective and well tolerated front-line treatment in patients with ABC.
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  • 36
    ISSN: 1569-8041
    Keywords: breast cancer ; p53 ; prognostic factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:There is heterogeneity of methods and conflictingresults concerning the prognostic value of p53 in node-negativebreast cancer. The clinical value of a quantitative method for measuringtumoral p53 content still needs to be evaluated. Patients and methods: A long-term retrospective study wasconducted on 297 node-negative patients with a median follow-up greater than10 years (11 years, 101–172 months). Classic prognostic factors wereconsidered including age, tumor size, histoprognostic grade and estradiol (ER)and progesterone receptors (PR). In addition, the value of p53 determination (immunoluminometric assay in tumor cytosol) was assessed forthis long follow-up period. Results: p53 concentrations were significantly linked tothe histological grade (P = 0.001), to tumor size (P = 0.02)and ER status (P = 0.01). Higher p53 tumoral concentrationswere found in tumors with large size, pejorative histological grade andnegative ER status. In contrast, p53 tumoral concentrations were notinfluenced by menopausal or PR status. Multivariate Cox analysis demonstratesthat tumor size was the only significant predictor of disease-free survival(P = 0.049) with a risk factor at 1.38. As regards specific survival,univariate Cox analysis indicates that p53 taken as a continuousvariable is a significant predictor (P = 0.024) together withhistological grade, tumor size and ER status. In a multivariate Cox analysisthere were two significant and independent variables for predicting overallsurvival: tumor size (P = 0.031) and ER status (P = 0.015)with the highest risk factor (RR = 2.14). Conclusions:The present investigation points out that theprognostic power of p53 tumor determination evaluated at more than10 years median survival is not higher than the well-recognized classicprognostic factors in node-negative breast cancer. The present data highlightthe need to assess the prognostic value of potentially new biological factorsin node-negative breast cancer on cohorts of patients followed over periodsin excess of 10 years.
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  • 37
    ISSN: 1569-8041
    Keywords: breast cancer ; genetic counselling ; risk assessment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:With the identification of genes predisposing tohereditary breast cancer, the accurate and consistent estimation of a woman'srisk of developing breast cancer based on her family history is of paramountimportance if national service guidelines are to be developed. Patients and methods:The residual lifetime risk of developingbreast cancer was estimated for 200 women attending a breast cancer geneticassessment clinic by three different methods currently in use in the UK. Riskswere computed on the basis of the Cancer and Steroid Hormone (CASH) study dataand were classified as ‘low/moderate’ (〈20%) or ‘high’(〉20%). These risk categories are representative of those currentlyused to allocate surveillance and genetic testing. Risks were then comparedto estimates derived by other methods used in current clinical practice,including those of Houlston and Murday. Results:The CASH data-based method ascribed 27% to thehigh risk category, as compared to 53% for the combined Houlston andMurday methods. A method based on the number of affected relatives aloneascribed only 14% to the high risk category. Overall, 108 (54%)women were placed in the same risk category by all three methods. Conclusions:This study demonstrates that there is a significantdegree of variability between methods currently used to estimate breast cancerrisk which has serious implications for individual patient management, serviceprovision and multicentre studies evaluating the benefits of genetic testingfor breast cancer susceptibility.
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  • 38
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    Annals of oncology 11 (2000), S. 495-496 
    ISSN: 1569-8041
    Keywords: breast cancer ; gemcitabine ; metastases ; vinorelbine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose:Gemcitabine (GEM) and vinorelbine (VNR) are both activeagainst advanced breast cancer (ABC), being able to induce a median ORR of25% and 40%, respectively. Because of their different mechanismof action and good tolerability, the combination of GEM and VNR has beentested in ABC. Patients and methods:Twenty-nine ABC patients pretreated withanthracycline-taxane were treated with GEM 1000 mg/m2 on day 1, 8,15, and VNR 25 mg/m2 on day 1 and 8 every twenty-eight days.Analysis of toxicity pattern, response rate, TTP and OS were carried out. Results:Twenty-nine patients were enrolled into the trial. TheORR was 48% (95% CI: 29–67): a CR was observed in threepatients (10%; 95% CI: 2–27), while eleven patients(38%; 95 CI: 21–58) achieved PR, eight (28%) had a SD, andseven (24%) progressed. Toxicity was mainly hematological and included:grade 3 leukopenia in 48% of cases without episodes of neutropenicfever, grade 3–4 thrombocytopenia in 10%, and grade 2 anemia in7%. Non-hematological toxicities were mild and rather infrequent. Conclusions:The GEM–VNR combination seems to be active inpretreated ABC with an acceptable toxicity pattern, and may well reppresentan interesting therapeutic choice after anthracycline/taxane regimens.
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  • 39
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    Annals of oncology 11 (2000), S. 469-474 
    ISSN: 1569-8041
    Keywords: breast cancer ; Prognostic factors ; psychosocial factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:Research interest in psychosocial predictors of theonset and course of cancer has been active since the 1950s. Recently wereported associations between psychological factors and survival in patientswith metastatic melanoma. We now report a replication of this study in asample of women with metastatic breast cancer. Patients and methods:Ninety-nine patients with metastatic breastcancer completed questionnaires measuring cognitive appraisal of threat,coping, psychological adjustment, perceived aim of treatment, social supportand quality of life, approximately four months after diagnosis. Survival wasmeasured from date of study entry to date of death or censored at the date oflast follow-up for surviving patients. Results:In a multivariate analysis, four factors independentlypredicted outcome. Patients with metastases in the liver, lung or pleurasurvived for a shorter duration (P 〈 0.001); older patients(P 〈 0.001) and those with a better appetite (P 〈0.05) also lived for a shorter time. Patients who minimised the impact ofcancer survived longer (a median of 29.1 vs. 23.9 months after study entry,P 〈 0.01). Conclusions:Minimisation was also significantly associated withoutcome in patients with metastatic melanoma who participated in anidentically designed study, reported elsewhere. This suggests thatminimisation may have a general impact on cancer progression and deservescloser scrutiny in other cancers.
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  • 40
    ISSN: 1569-8041
    Keywords: 5-FU ; breast cancer ; metastatic ; navelbine ; protracted continuous infusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:The protracted continuous infusion (PCI) of5-fluorouracil (5-FU) has proven in several studies an active and welltolerated treatment for advanced, pretreated breast cancer. Navelbine has alsoactivity in this setting. Patients and methods:Heavily pretreated patients with metastaticbreast carcinoma were eligible for the study. Treatment consisted of 5-FU 250mg/m2 given as a PCI by an elastomeric pump and navelbine 20mg/m2 on days 1 and 8, every four weeks. Eighty-three patients(median age 54 years; range 32–82 years) entered the study. The mediannumber of metastatic tumour sites was 2, with visceral involvement in 56patients. Apart from five patients with contraindications, all patients hadbeen pretreated with anthracyclines. Thirty-one patients had received taxanesand seventy-four bolus 5-FU. Results:A median of 5 cycles (range 1–14) per patient wasadministered. The median duration of 5-FU infusion was 17 weeks (range, 4-90).In the 80 evaluable patients (3 not yet evaluable) 12 complete remissions and24 partial remissions occurred (response rate, 45%). Median durationof response was 9 months. Toxicity was mild. Median survival was 20 months. Conclusions:PCI–5-FU combined with navelbine offers areasonable chance of tumour regression with modest side effects in patientswith heavily pretreated breast cancer.
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  • 41
    ISSN: 1569-8041
    Keywords: adjuvant chemotherapy ; attitudes ; breast cancer ; consensus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:A worldwide variation in policy is seen regardingadjuvant systemic treatment for node negative breast cancer (NNBC). After thefirst presentations of the 10-year EBCTCG results, a study was carried out inthe Netherlands to assess patterns of care and to obtain the views ofoncologists as to what constitutes a worthwhile benefit from treatment. Methods:A questionnaire regarding patterns of use of andpreferences for adjuvant chemotherapy in younger women was mailed to surgical,medical and radiation oncologists in the Netherlands. Results:Thirty-five percent stated that NNBC patients under 50in their hospital never received adjuvant chemotherapy. The majorityconsidered a 10-year survival gain of 6%–10% sufficientto warrant the use of chemotherapy in patients under 50. Surgical oncologistsrequired a larger benefit from treatment than radiotherapists and medicaloncologists. The more frequently oncologists treated patients in a researchcontext, the less benefit they required from treatment to make it worthwhile. Conclusions:Data such as these are valuable input into theprocess of guideline development, and may help discussion within theprofession as to what benefit offsets the burden of treatment.
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  • 42
    ISSN: 1569-8041
    Keywords: breast cancer ; clinical trial ; docetaxel ; hepatic metastases
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:Previous phase II studies of docetaxel have indicatedthat hepatic metastases from breast cancer respond well to first-linetreatment with docetaxel. The objective of this prospective, open label phaseII study therefore was specifically to evaluate the activity and safety ofdocetaxel in this indication. Patients and methods:The study recruited 47 women (mean age 50years, range 33–66 years) with hepatic metastases from breast cancer whofulfilled the eligibility criteria. After premedication with steroids,patients received a one-hour intravenous infusion of docetaxel 100mg/m2 at three-weekly intervals for up to eight cycles. Responseto treatment during medication was assessed after three, six and whereappropriate, eight cycles and every three month follow-up thereafter, untildisease progression or death. Results:The best overall response rate (ORR) for evaluablepatients was 64.3% (95% CI: 48.0%–78.5%).In terms of the primary efficacy parameters, the ORR at the sixth cycle oftreatment was 62% (95% CI: 45%–80%) with17% complete responses. The median duration of response was 139 days(95% CI: 111–216 days) and the median survival durationcalculated on an intent-to-treat basis was 335 days (227–568 days,95% CI). One (2%) toxic death was reported. Conclusions:Docetaxel is a highly effective cytotoxic agent inthe treatment of patients with liver metastases from breast cancer.
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  • 43
    ISSN: 1569-8041
    Keywords: breast cancer ; lymph nodes ; sentinel lymph node biopsy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:Sentinel node biopsy (SNB) has been proposed as analternative to axillary lymph-node dissection (ALND) in breast cancer. Beforeimplementing SNB in our practice, we wished to test its validity by comparingit to the standard ALND, both in our hands and with other reported series. Patients and methods:One hundred thirty-two patients wereincluded prospectively. SNB and immediate ALND were performed. For SNB, atechnetium-colloid was used to produce preoperative lymphoscintigraphy andintraoperative gamma-probe search for the SN. Serial sectioning andimmunostains were used on the SN. A comprehensive review of the literature wasdone in order to run a meta-analysis of diagnostic tests using a summaryreceiver operating characteristic curve (SROC) to calculate the pooledparameters of sensitivity and associated 95% confidence interval(95% CI), including our own data. Results:Our technical success rate was 96%. Localsensitivity was 96%, with a 95% CI from85%–99%. Seven patients were upstaged by the SNB. Aliterature search identified 18 studies published from 1996–1999.Estimates of sensitivity ranged from 83%–100%. The pooleddata meta-analysis gave a global sensitivity of 91%, with a 95%CI from 89%–93%. The area under the global SROC curve was0.9967. Conclusions:The minimally invasive SNB was shown to be apractical alternative to ALND. We propose to use local as well as globalsensitivity and associated 95% CI to test the validity of SNB in theclinical setting. Due to limitations of ALND as the golden standard, SNB canin fact be considered a more accurate method for nodal staging.
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  • 44
    ISSN: 1569-8041
    Keywords: docetaxel + gemcitabine ; docetaxel + vinorelbine ; phase I ; breast cancer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose:The objective of this study was to determine thedocetaxel MTD when combined with gemcitabine or vinorelbine in advanced breastcancer patients who had received previous anthracycline-based chemotherapy foradvanced disease. Patients and methods:Advanced breast cancer patients aged between18 and 70 with ECOG PS 0–2 who had not responded to, or had relapsedafter, first-line anthracycline-based chemotherapy, were randomized to receiveeither gemcitabine 1000 mg/m2 or vinorelbine 25 mg/m2in combination with escalating doses of docetaxel (starting from 30mg/m2), all on days 1 and 8 every three weeks. Escalation wasstopped if 〉33% of patients treated at a given dose level showed DLTat the first cycle. Results:A total of 34 patients with locally advanced (8) ormetastatic disease (26) were treated, for a total of 94 cycles delivered.Nineteen patients received docetaxel in combination with gemcitabine and 15with vinorelbine. All patients had been pretreated with anthracyclines, and24 of 34 had also received weekly dose-dense paclitaxel. A docetaxel dose of40/m2 proved to be safe when combined on days 1 and 8 withgemcitabine, while a dose of 35 mg/m2 was tolerated in combinationwith vinorelbine. Overall, nine episodes of DLT, all of them neutropenia,occurred at the first cycle. Considering all 94 cyles, grades 3 or 4neutropenia and thrombocytopenia occurred in 15 (44%), and 7(20%) patients. Non-hematologic toxicity was mild, except for threecases of grade 2 peripheral neuropathy. All patients were assessed forresponse on an 'intent-to-treat' basis. Overall, five partial responses wererecorded (docetaxel + gemcitabine = 3 and docetaxel + vinorelbine = 2), fora 15% (95% CI: 5%–31%) overall responserate. Only 1 of 24 (4%) patients who had received weekly dose-densepaclitaxel responded to treatment. Conclusions:The weekly docetaxel administration in combinationwith either gemcitabine or vinorelbine is a well-tolerated treatment forheavily pretreated advanced breast cancer patients. This approach, althoughsometimes capable of achieving a major response, does not seem advisable inadvanced breast cancer patients refractory to both anthracyclines andpaclitaxel.
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  • 45
    ISSN: 1569-8041
    Keywords: breast cancer ; estrogen receptor ; progesterone receptor ; preoperative chemotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background:We recently demonstrated that in premenopausalpatients with estrogen receptors (ER)-absent tumors, early initiation ofsystemic chemotherapy after primary surgery might improve outcome. These dataindicate a different responsiveness to chemotherapy for tumors not expressinghormone receptors. To test this hypothesis we evaluated the responsiveness topreoperative chemotherapy in patients with ER and progesterone receptors(PgR)-absent tumors. Patients and methods:Patients with biopsy-provenT2–T3, N0–2 breast cancertreated at a single institution from January 1995 to August 1999 withpreoperative chemotherapy were retrospectively evaluated. ER and PgR weredetermined immunohistochemically and classified for this purpose as absent(0% of the cells positive) or positive (≥1% of the cells). Results:On 117 evaluable patients 72 had an objective response(61%). A significant difference in response was observed for patientswith ER and PgR absent compared with those with ER and/or PgR-positive tumors(82% vs. 57%,P = 0.03 Fishers's exact test).Pathological complete remission rates were also significantly different in thetwo groups (23% vs. 7%, respectively; P = 0.04). Conclusions:The different degree of response according to hormonereceptors expression supports the hypothesis that tumors not expressing bothER and PgR might represent a different clinical entity in terms ofchemotherapy responsiveness.
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  • 46
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    The environmentalist 20 (2000), S. 257-271 
    ISSN: 1573-2991
    Keywords: evolution ; tides ; sea level ; time series
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract The increasing use of computers since the 1960s, has implied the digitization of observations in meteorology, oceanography and other observational sciences. Enough data has been accumulated to suggest that some patterns of evolution in the world may be discernable. The present article deals with what appears as changing tides around Canada.
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  • 47
    ISSN: 1573-4927
    Keywords: ancient endogenous provirus ; evolution ; retrotransposition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A new family of murine endogenous proviruses (VL6.0) is described here. The intact provirus is near 6 kb in length and shows a genomic organization of 5" LTR, gag, pol, env, and 3" LTR. The primer binding site (PBS) is that of a tRNAgly. The lack of functional open reading frames and occurrence of significant gaps in most, if not all, members of this group show it to be ancient. Our estimate of copy number per haploid genome is 30+. Members of this group have been isolated from Mus musculus domesticus, M. m. casteneus, M. m. hortulanus, M. caroli, and M. spretus. The occurrence of these sequences throughout such diverse members of the genus Mus may indicate that the date of the original infection predated the divergence of the extant Mus lineages at around 2.5 million years ago. Analysis of gap (deletion/insertion) patterns indicates that these sequences may have proliferated within the Mus genome by a mechanism of reverse transcriptase-mediated transposition. As yet, there are no closely related murine retroviruses described. The closest mammalian retrovirus based on sequence similarity is from the miniature swine (Sus scrofa).
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  • 48
    ISSN: 1618-2545
    Keywords: biogeography ; calmodulin ; DNA sequence ; elongation factor EF-1α ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Phylogenetic relationships within theGibberella fujikuroi species complex were extended to newly discovered strains using nucleotide characters obtained by sequencing polymerase chain reaction (PCR) amplified DNA from 4 loci used in a previous study [nuclear large subunit 28S rDNA, nuclear ribosomal internal transcribed spacer (ITS) region, mitochondriaal small subunit (mtSSU) ribosomal DNA, and β-tubulin] together with two newly sampled protein-encoding nuclear genes, translation elongation factor EF-1α and calmodulin. Sequences from the ribosomal ITS region were analyzed separately and found to contain of two highly divergent, nonorthologous ITS2 types. Phylogenetic analysis of the individual and combined datasets identified 10 new phylogenetically distinct species distributed among the following three areas: 2 within Asia and 4 within both Africa and South America. Hypotheses of the monophyly ofFusarium subglutinans and its two formae speciales, f. sp.pini and f. sp.ananas, were strongly rejected by a likelihood analysis. Maximum parsimony results further indicate that the protein-encoding nuclear genes provide considerably more phylogenetic signal that the ribosomal genes sequenced. Relative apparent synapomorphy analysis was used to detect long-branch attraction taxa and to obtain a statistical measure of phylogenetic signal in the individual and combined datasets.
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  • 49
    ISSN: 1618-2545
    Keywords: Ascomycota ; evolution ; pyrenomycetes ; systematics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract To investigate the systematic position of the unitunicate pyremomycetePapulosa amerospora, we performed phylogenetic analyses of SSU rDNA sequences from 37 ascomycetes. Among these sequences were some new ones from taxa that might be related toPapulosa: Hyponectriaceae (Hyponectria buxi, Monographella nivalis), Phyllachorales (Phyllachora graminis), and Xylariales (Barrmaelia melanotes, Poronia punctata). Our results showed 100% bootstrap support for a clade of all unitunicate pyrenomycetes, the class Sordariomycetes. We also found strong support for recognizing the subclasses Hypocreomycetidae and Xylariomycetidae. The remaining taxa, belonging to subclass Sordariomycetidae, appeared as a polyphyletic group in one analysis, but was monophyletic when shorter SSU sequences were used.Barrmaelia melanotes, Poronia punctata, Hyponectria buxi, andMonographella nivalis are members of Xylariomycetidae, but we could not determine whetherMonographella should be included in Hyponectriaceae. The new family Papulosaceae is erected forPapulosa on molecular and morphological bases, but the exact systematic position ofPapulosa within subclass Sordariomycetidae is still uncertain, since the genus did not cluster consistently with any of the included taxa. Phyllachorales are not closely related to Diaporthales, as previously suggested.
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  • 50
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    Glycoconjugate journal 17 (2000), S. 465-483 
    ISSN: 1573-4986
    Keywords: N-acetylglucosaminyltransferases ; glycosylation ; glycoproteins ; Golgi complex ; evolution ; development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract This review covers discoveries made over the past 30–35 years that were important to our understanding of the synthetic pathway required for initiation of the antennae or branches on complex N-glycans and O-glycans. The review deals primarily with the author's contributions but the relevant work of other laboratories is also discussed. The focus of the review is almost entirely on the glycosyltransferases involved in the process. The following topics are discussed. (1) The localization of the synthesis of complex N-glycan antennae to the Golgi apparatus. (2) The “evolutionary boundary” at the stage in N-glycan processing where there is a change from oligomannose to complex N-glycans; this switch correlates with the appearance of multicellular organisms. (3) The discovery of the three enzymes which play a key role in this switch, N-acetylglucosaminyltransferases I and II and mannosidase II. (4) The “yellow brick road” which leads from oligomannose to highly branched complex N-glycans with emphasis on the enzymes involved in the process and the factors which control the routes of synthesis. (5) A short discussion of the characteristics of the enzymes involved and of the genes that encode them. (6) The role of complex N-glycans in mammalian and Caenorhabditis elegans development. (7) The crystal structure of N-acetylglucosaminyltransferase I. (8) The discovery of the enzymes which synthesize O-glycan cores 1, 2, 3 and 4 and their elongation.
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  • 51
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    Journal of bioeconomics 2 (2000), S. 9-23 
    ISSN: 1573-6989
    Keywords: evolution ; altruism ; morality ; utilitarianism ; Marxism ; Rawls ; fairness
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Economics
    Notes: Abstract Several evolutionary mechanisms have been identified in the literature that would generate altruism in humans. The most powerful (except for kin selection) and most controversial is group selection, as recently analyzed by Sober & D.S. Wilson. I do not take a stand on the issue of the existence of group selection. Instead, I examine the level of human altruism that could exist if group selection were an engine of human evolution. For the Sober & Wilson mechanism to work, groups practicing altruism must grow faster than other groups. I call altruistic behavior that would lead to faster growth ‘efficient altruism’. This often consists of cooperation in a prisoner's dilemma. ltruistic acts such as helping a temporarily hungry or injured person would qualify as efficient altruism. Efficient altruism would also require monitoring recipients to avoid shirking. Utilitarianism would be an ethical system consistent with efficient altruism, but Marxism or the Rawlsian system would not. Discussions of efficient altruism also help understand intuitions about fairness. We perceive those behaviors as ‘fair’ that are consistent with efficient altruism. It is important to understand that, even if humans are selected to be altruistic, the forms of altruism that might exist must be carefully considered and ircumscribed.
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  • 52
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    Biology and philosophy 15 (2000), S. 443-463 
    ISSN: 1572-8404
    Keywords: David Hull ; evolution ; selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract One of the principal difficulties in assessing Science as aProcess (Hull 1988) is determining the relationship between the various elements of Hull's theory. In particular, it is hard to understand precisely how conceptual selection is related to Hull's account of the social dynamics of science. This essay aims to clarify the relation between these aspects of his theory by examining his discussion of the``demic structure'' of science. I conclude that the social account cando significant explanatory work independently of the selectionistaccount. Further, I maintain that Hull's treatment of the demicstructure of science points us toward an important set of issues insocial epistemology. If my reading of Science as a Process iscorrect, then most of Hull's critics (e.g., those who focus solelyon his account of conceptual selection) have ignored promisingaspects of his theory.
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  • 53
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    Biology and philosophy 15 (2000), S. 493-508 
    ISSN: 1572-8404
    Keywords: complexity ; entropy balance ; environment independence ; evolution ; information fundamental identity ; uncertainty
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract Some real objects show a very particular tendency: that of becomingindependent with regard to the uncertainty of their surroundings. This isachieved by the exchange of three quantities: matter, energy andinformation. A conceptual framework, based on both Non-equilibriumThermodynamic and the Mathematical Theory of Communication is proposedin order to review the concept of change in living individuals. Three mainsituations are discussed in this context: passive independence inconnection with resistant living forms (such as seeds, spores, hibernation,...), active independence in connection with the life span of aliving individual (whether an ant or an ant farm), and the newindependence in connection with the general debate of biological evolution.
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  • 54
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    Biology and philosophy 15 (2000), S. 641-668 
    ISSN: 1572-8404
    Keywords: complexity ; evolution ; function ; modularity ; parts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract The functional complexity, or the number of functions, of organisms hasfigured prominently in certain theoretical and empirical work inevolutionary biology. Large-scale trends in functional complexity andcorrelations between functional complexity and other variables, such assize, have been proposed. However, the notion of number of functions hasalso been operationally intractable, in that no method has been developedfor counting functions in an organism in a systematic and reliable way.Thus, studies have had to rely on the largely unsupported assumption thatnumber of functions can be measured indirectly, by using number ofmorphological, physiological, and behavioral “parts” as a proxy. Here, amodel is developed that supports this assumption. Specifically, the modelpredicts that few parts will have many functions overlapping in them, andtherefore the variance in number of functions per part will be low. If so,then number of parts is expected to be well correlated with number offunctions, and we can use part counts as proxies for function counts incomparative studies of organisms, even when part counts are low. Alsodiscussed briefly is a strategy for identifying certain kinds of parts inorganisms in a systematic way.
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  • 55
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    Biology and philosophy 15 (2000), S. 713-732 
    ISSN: 1572-8404
    Keywords: Darwin ; error theory ; ethics ; evolution ; evolutionary ethics ; Mackie ; naturalistic fallacy ; Ruse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract Suppose that the human tendency to think of certain actions andomissions as morally required – a notion that surely lies at the heart of moral discourse – is a trait that has been naturallyselected for. Many have thought that from this premise we canjustify or vindicate moral concepts. I argue that this is mistaken, and defend Michael Ruse's view that the moreplausible implication is an error theory – the idea thatmorality is an illusion foisted upon us by evolution. Thenaturalistic fallacy is a red herring in this debate,since there is really nothing that counts as a ‘fallacy’ at all. If morality is an illusion, it appears to followthat we should, upon discovering this, abolish moraldiscourse on pain of irrationality. I argue that thisconclusion is too hasty, and that we may be able usefullyto employ a moral discourse, warts and all, withoutbelieving in it.
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  • 56
    ISSN: 1618-2545
    Keywords: Ascomycota ; evolution ; molecular clock ; plant pathogen ; powdery mildew
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Phylogenetic relationships of Erysiphales within Ascomycota were inferred from the newly determined sequences of the 18S rDNA and partial sequences of the 28S rDNA including the D1 and D2 regions of 10 Erysiphales taxa. Phylogenetic analyses revealed that the Erysiphales form a distinct clade among ascomycetous fungi suggesting that the Erysiphales diverged from a single ancestral taxon. The Myxotrichaceae of the Onygenales was distantly related to the other onygenalean families and was the sister group to the Erysiphales calde, with which it combined to form a clade. The Erysiphales/Myxotrichaceae clade was also closely related to some discomycetous fungi (Leotiales, Cyttariales and Thelebolaceae) including taxa that form cleistothecial ascomata. The present molecular analyses as well as previously reported morphological observations suggest the possible existence of a novel evolutionary pathway from cleistothecial discomycetous fungi to Erysiphales and Myxotrichaceae. However, since most of these fungi, except for the Erysiphales, are saprophytic on dung and/or plant materials, the questions of how and why an obligate biotroph like the Erysiphales radiated from the saprophytic fungi remain to be addressed. We also estimated the radiation time of the Erysiphales using the 18S rDNA sequences and the two molecular clockes that have been previously reported. The calculation showed that the Erysiphales split from the Myxotrichaceae 190–127 myr ago. Since the radiation time of the Erysiphales does not exceed 230 myr ago, even when allowance is made for the uncertainty of the molecular clocks, it is possible to consider that the Erysiphales evolved after the radiation of angiosperms. The results of our calculation also showed that the first radiation within the Erysiphales (138–92 myr ago) coincided with the date of a major diversification of angiosperms (130–90 myr ago). These results may support our early assumption that the radiation of the Erysiphales coincided with the evolution of angiosperm plants.
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  • 57
    ISSN: 1573-7276
    Keywords: bone sialoprotein ; osteopontin ; breast cancer ; metastasis ; bone metastases ; immunohistochemistry ; in situ hybridization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Bone sialoprotein (BSP) and osteopontin (OPN) are prominent, mineral-associated proteins in the extracellular matrix of bone that have been implicated in the metastatic activity of cancer cells. The expression of BSP, which is normally restricted to mineralizing tissues, has been observed in cancers with a high propensity for forming bone metastases. To investigate the relationship between BSP expression and the formation of bone metastases we have conducted an initial study of the expression of BSP in 10 intraductal breast carcinoma bone metastases using immunostaining and in situ hybridization, and compared the expression with OPN. The metastases were characterized by the infiltration of tumour cells into bone with extensive bone resorption evident. Moderate to strong staining for BSP was observed in all (100%) carcinomas, which also expressed BSP mRNA as determined by in situ hybridization. Variable staining for BSP was also observed in the mineralized bone and expression of BSP mRNA could be observed in osteoblastic cells on the bone surface and in some osteocytes at sites of bone remodelling. Contrary to a previous report, BSP expression could be demonstrated by PCR in three breast cancer cell lines, MCF-7, T47-D and MDA-MB-231. Moreover, in sub-cutaneous tumours formed by MDA-MB-231 breast cancer cells injected into athymic mice, higher immunostaining for BSP was seen in large ulcerating tumours in which mineral deposits were formed. In contrast to BSP, staining for OPN in bone metastases was generally restricted to the interface between tumor cells and bone surface of the carcinomas. While OPN staining was also observed in the cytoplasm of osteoclasts, which showed strong hybridization to a digoxygenin-labelled OPN cRNA probe, expression of OPN was not clearly detectable in the tumour cells. These studies provide the first demonstration of BSP expression by tumour cells in bone metastases and support the concept that BSP may have a role in targeting metastatic cells to bone. Expression of OPN in bone metastases appears to be related to increased bone resorptive activity by osteoclasts.
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  • 58
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    Clinical & experimental metastasis 18 (2000), S. 573-580 
    ISSN: 1573-7276
    Keywords: breast cancer ; cell motility ; KGF ; metastasis ; MCF-7 ; T-47D ; ZR-75-1
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Endogenous growth factors and cytokines are known to have a major influence on the progression, motility and invasiveness of tumor cells. We have reported previously that conditioned media from mouse fibroblasts increases the motility of breast cancer cells. Further, we determined that keratinocyte growth factor (KGF) was an active factor from mouse fibroblasts responsible for most of the motility response in breast cancer cells. The present study examined the effect of human KGF on the motility of estrogen receptor (ER)-positive and ER-negative human breast cancer cell lines in culture using time-lapse videomicroscopy to quantify cell motility. In the present study we observed that recombinant human KGF enhanced several parameters of cellular motility in ER-positive cells but not in ER-negative cell lines. Further, we observed that the level of KGF receptor (KGFR) expression in ER-positive cells was much greater than in the ER-negative cell lines. The motility response to KGF was found to be both dose-and time-dependent. Of the three ER-positive breast cancer cell lines tested, MCF-7 cells were the most responsive to KGF stimulation. Finally, MCF-7 cells grown in estrogen-depleted media did not respond to KGF. These results suggest that KGF from stromal tissue surrounding a primary tumor mass can enhance tumor cell motility and may be an early signal in the progression of breast cancer cells to a more motile and metastatic phenotype. Thus, KGF, KGFR and/or the KGF signaling pathway may be important therapeutic targets for the treatment or prevention of breast cancer metastasis.
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  • 59
    ISSN: 1573-7276
    Keywords: breast cancer ; chromosome 11q13 ; gap junctions ; metastasis suppressor gene ; motility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Introduction of normal, neomycin-tagged human chromosome 11 (neo11) reduces the metastatic capacity of MDA-MB-435 human breast carcinoma cells by 70–90% without affecting tumorigenicity. Differential display comparing MDA-MB-435 and neo11/435 led to the discovery of a human breast carcinoma metastasis suppressor gene, BRMS1, which maps to chromosome 11q13.1–q13.2. Stable transfectants of MDA-MB-435 and MDA-MB-231 breast carcinoma cells with BRMS1 cDNA still form progressively growing, locally invasive tumors when injected in mammary fat pads of athymic mice but exhibit significantly lower metastatic potential (50–90% inhibition) to lungs and regional lymph nodes. To begin elucidating the mechanism(s) of action, we measured the ability of BRMS1 to perturb individual steps of the metastatic cascade modeled in vitro. Consistent differences were not observed for adhesion to extracellular matrix components (laminin, fibronectin, type IV collagen, type I collagen, Matrigel); growth rates in vitro or in vivo; expression of matrix metalloproteinases, heparanase, or invasion. Likewise, BRMS1 expression did not up regulate expression of other metastasis suppressors, such as NM23, Kai1, KiSS1 or E-cadherin. Motility of BRMS1 transfectants was modestly inhibited (30–60%) compared to parental and vector-only transfectants. Ability to grow in soft agar was also decreased in MDA-MB-435 cells by 80–89%, but the decrease for MDA-MB-231 was less (13–15% reduction). Also, transfection and re-expression of BRMS1 restored the ability of human breast carcinoma cells to form functional homotypic gap junctions. Collectively, these data suggest that BRMS1 suppresses metastasis of human breast carcinoma by complex, atypical mechanisms.
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  • 60
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    International journal of historical archaeology 4 (2000), S. 71-112 
    ISSN: 1573-7748
    Keywords: evolution ; archaeology ; natural selection ; classification ; style ; function
    Source: Springer Online Journal Archives 1860-2000
    Topics: Archaeology
    Notes: Abstract Over the past decade or so, an increasing number of archaeologists have begun to show interest in employing Darwinian evolutionary theory to explain variations in the material record. Epistemological and methodological issues surrounding the implementation of Darwinian evolutionism in archaeology are numerous, the most basic of which is that Darwinism embodies a materialist perspective, whereas archaeology traditionally has maintained an essentialist outlook. Stemming from this dichotomy are fundamental differences in such things as how units are created and how they are used to measure change. As archaeologists grapple with these issues, specific examples of how Darwinian evolutionism can be used to build historical narratives and create historical explanations are appearing with more frequency, but with few exceptions, proponents have focused specifically on the prehistoric record. This gives the impression that Darwinian evolutionism is not applicable to the more-recent material record, which is decidedly not the case. The kind of evolutionism proposed here transcends the age of the record under investigation.
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  • 61
    ISSN: 1573-7373
    Keywords: choroidal metastasis ; leptomeningeal carcinomatosis ; breast cancer ; docetaxel ; mitoxantrone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Choroidal metastases from breast cancer represent an unusual metastatic presentation that has been traditionally treated with radiation therapy. Herein, we report a case of metastatic breast cancer presenting with pulmonary, cutaneous, lymph node and symptomatic choroidal metastases treated with systemic combination chemotherapy incorporating docetaxel and mitoxantrone without induction or consolidation radiation therapy to control visual symptoms from choroidal metastases. The patient experienced a durable complete remission in all metastatic sites that was maintained for 21 months since the initiation of chemotherapy, afterwhich she developed isolated leptomeningeal carcinomatosis managed successfully with intensive intrathecal methotrexate and whole brain irradiation leading to a new complete remission maintained until this report; 11 months after its presentation. This is the first case to our knowledge reporting complete regression of choroidal metastases with docetaxel-based chemotherapy as the only treatment modality and subsequent isolated leptomeningeal carcinomatosis recurrence.
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  • 62
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    Journal of happiness studies 1 (2000), S. 323-349 
    ISSN: 1573-7780
    Keywords: progress ; quality of life ; happiness ; optimism ; pessimism ; social indicators ; forecasting ; world view ; evolution ; development.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Psychology
    Notes: Abstract This paper argues that both the relativist and the pessimist critiques of the idea of progress are inadequate. Progress is defined as increase in global quality of life (QOL). Such QOL is intrinsically subjective, but not relative. It can be reliably measured through “life satisfaction”-type questions. The “World Database of Happiness” provides extensive data on social, economic and psychological factors that correlate with overall QOL. They include wealth, health, security, knowledge, freedom and equality. Various statistical data suggest that all these QOL indicators have undergone significant improvements during the last half century, in most of the world. This gives strong support to the thesis that progress objectively occurs.
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  • 63
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    Journal of happiness studies 1 (2000), S. 351-374 
    ISSN: 1573-7780
    Keywords: progress ; quality of life ; optimism ; pessimism ; social indicators ; world view ; evolution ; development ; global change ; information overload.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Psychology
    Notes: Abstract This paper attempts to update the 18th century concept of progress by an evolutionary theoretical framework, while replying to some of the contemporary critiques. Progress, understood as increase in fitness (or its proxy, quality of life) necessarily accompanies evolution by natural selection. In socio-cultural evolution, this mechanism is reinforced by growth of knowledge and virtuous cycles, but can be accompanied by negative side-effects such as overshooting and parasitism. The most pressing of the contemporary side-effects, such as pollution and the increased pace of life, are discussed, but it is concluded that they can be tackled without really endangering global progress. The anxiety that they engender is unfortunately amplified by a “bad news” bias in the media, leading to an inappropriately pessimistic view of the situation by the public.
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  • 64
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    Neural processing letters 11 (2000), S. 29-38 
    ISSN: 1573-773X
    Keywords: evolution ; online ; game ; neural ; network ; genetic ; real-time
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract In standard neuro-evolution, a population of networks is evolved in a task, and the network that best solves the task is found. This network is then fixed and used to solve future instances of the problem. Networks evolved in this way do not handle real-time interaction very well. It is hard to evolve a solution ahead of time that can cope effectively with all the possible environments that might arise in the future and with all the possible ways someone may interact with it. This paper proposes evolving feedforward neural networks online to create agents that improve their performance through real-time interaction. This approach is demonstrated in a game world where neural-network-controlled individuals play against humans. Through evolution, these individuals learn to react to varying opponents while appropriately taking into account conflicting goals. After initial evaluation offline, the population is allowed to evolve online, and its performance improves considerably. The population not only adapts to novel situations brought about by changing strategies in the opponent and the game layout, but it also improves its performance in situations that it has already seen in offline training. This paper will describe an implementation of online evolution and shows that it is a practical method that exceeds the performance of offline evolution alone.
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  • 65
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    Journal of mammary gland biology and neoplasia 5 (2000), S. 351-364 
    ISSN: 1573-7039
    Keywords: Human ; breast cancer ; premalignant
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Most human invasive breast cancers (IBCs)4 arise from preexisting benign lesions. There are many types of benign lesions in the human breast and only a few appear to have significant premalignant potential (atypical hyperplasias and in situ carcinomas). These lesions are relatively common and only a small proportion progress to IBC. They are currently defined by their histological features and their prognosis is imprecisely estimated from indirect evidence based on epidemiological studies. Although lesions within specific categories look alike, they must possess morphologically silent biological differences motivating some to remain stable and others to progress. Understanding the biological changes responsible for the development and progression of premalignant disease is a very active area of medical research. Progress in this area may provide new opportunities for breast cancer prevention by providing strategies to treat premalignant lesions before they develop or become cancerous. A large number of biological features have been evaluated in this setting during the past decade. This review discusses a few features that appear to be particularly important and have been studied in a relatively comprehensive manner.
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  • 66
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    Journal of mammary gland biology and neoplasia 5 (2000), S. 409-420 
    ISSN: 1573-7039
    Keywords: Pre-malignancy ; breast cancer ; experimental model ; rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract While a number of agents have been shown to induce mammary carcinogenesis in the rat, premalignant stages of the disease have been best characterized in chemically-induced models, specifically those initiated by either 7,12 dimethylbenz[α]anthracene (DMBA)4 or 1-methyl-1-nitrosourea (MNU). In general, it appears that epithelial cells in mammary terminal end buds or terminal ductules are the targets of carcinogenic initiation, and that a series of morphologically identifiable steps are involved in the development of mammary carcinoma. The premalignant steps include ductal hyperplasia of the usual type and carcinoma in situ of the cribriform or comedo type; atypical ductal hyperplasia has not been reported. Thus the histogenesis of lesions occurring in chemically induced mammary carcinogenesis in the rat is similar to that observed in the human; although, the spectrum of lesions observed in the rat is limited. Opportunities to investigate the biological and molecular characteristics of premalignant breast disease in the rat are presented.
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  • 67
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    Journal of mammalian evolution 7 (2000), S. 1-22 
    ISSN: 1573-7055
    Keywords: Dasyurus ; marsupials ; control region ; mtDNA ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract There has been a great deal of interest in determining phylogenetic relationships within the family Dasyuridae due to the widespread distribution, ecological diversity, and relative plesiomorphy of this taxon within the Australasian marsupial radiation. In the past, it has been extremely problematic to determine the phylogenetic relationships among species within Dasyurus, with numerous studies using both morphological and molecular characters providing different topologies. Here, the mitochondrial DNA (mtDNA) control region is used as a novel set of characters in an attempt to identify relationships among the six closely related extant species. Sequences were obtained from multiple individuals representing all extant species of quolls including, when possible, individuals from different geographical regions. Sequences were analyzed using both parsimony criteria and neighbor-joining methods. Results presented here concur with those of Krajewski et al. (1997) in (1) placing D. geoffroii in a highly supported clade with D. spartacus, (2) resolving a monophyletic group of D. albopunctatus + D. geoffroii + D. spartacus, and (3) placing D. hallucatus as the sister taxon to all other species of quolls. Results also show two highly supported and geographically distinct clades of D. maculatus (Tasmanian and mainland) that do not correspond to the currently used subspecific nomenclature. Preliminary results also indicate that there are different clades among geographic groups of D. hallucatus that warrant further investigation. The mtDNA control region is a highly variable locus and may be used in forensic tests for species identification in this genus.
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  • 68
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    Journal of mammary gland biology and neoplasia 5 (2000), S. 139-163 
    ISSN: 1573-7039
    Keywords: breast cancer ; pathology atlas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This article illustrates the most common benign and malignant lesions in the breast, and is intended for the biologist working in the area of breast cancer and breast biology, not for the practicing pathologist. The atlas covers benign proliferative lesions, atypical lesions, variants of in situ cancer, the main types of invasive cancers, spindle cell lesions, and examples of vascular and lymphatic spread. Some entities are included to illustrate a point of particular relevance to the biology and histogenesis of the lesions. Some controversial diagnostic areas are considered, along with the relative risk of developing breast cancer associated with some of the proliferative lesions. The content of this atlas should be read in conjunction with the companion article by Howard and Gusterson in this issue. Their article covers the cellular origin of epithelial and stromal tumors and presents a description of some of the common benign proliferative lesions that are considered to be components of the normal spectrum of changes seen at postmortem or in biopsies.
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  • 69
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    Journal of mammary gland biology and neoplasia 5 (2000), S. 341-349 
    ISSN: 1573-7039
    Keywords: Premalignancy ; risk ; breast cancer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Premalignant breast disease in humans is a concept that admits to a broad range of elements and possible determinants predicting the likelihood of developing breast cancer. Most of these elements are relative, such as the risk of breast cancer for women that is 130 times that of men and peaks at a younger age by about 10 years. Breast cancer is clearly a stochastic, multifactorial process that evolves over many years in which we must make predictions by likelihood. This review will present the most specially defined and reliably proven of these elements, highlighting anatomic and molecular factors.
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  • 70
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    Biogerontology 1 (2000), S. 289-307 
    ISSN: 1573-6768
    Keywords: comparative nematode ageing ; evolution ; Caenorhabditis elegans ; Onchocerca volvulus ; Strongyloides ratti
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In the developing field of biological gerontology, rapid advances have recently been made in the genetics of ageing in the nematode Caenorhabditis elegans. The aim of this work is to develop an understanding of the general mechanisms determining the ageing process. Within the last decade the prospect of actually achieving this somewhat hubristic aim has begun to look startlingly real. In this context, knowledge of every aspect of the biology of ageing in nematodes is of added interest. Here the patterns of ageing observed among parasitic and free-living nematodes are surveyed and compared. Like insects, nematode species exhibit enormous differences in the rate of ageing, with maximum life spans varying over more than a 1000-fold range, from three days in free-living Rhabdias bufonis adults, to at least 15 years in the filarial parasite Loa loa. The possible evolutionary and mechanistic causes of such differences in ageing are discussed.
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  • 71
    ISSN: 1573-6857
    Keywords: evolution ; Oryza ; retrotransposon ; rice ; wild species
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The Oryza officinalis complex is a genetically diverse, tertiary genepool of rice. We analyzed part of the primary structure of the integrase coding domain (ICD) of a gypsy-like retrotransposon from species of the O. officinalis species complex. PCR was performed with degenerate primers that hybridized to conserved sequences in the integrase genes of gypsy-type retrotransposons, using total DNA from different species of the O. officinalis complex as templates. Cloning and sequencing of the PCR products showed that the amplified fragments are highly homologous to each other (75–90%) and belong to one family of retrotransposons that is related to the previously studied RIRE-2 element from rice. Two main subfamilies of 292 and 351 bp were distinguished. Analysis of primary sequence data supports previous reports that sequence divergence during vertical transmission has been the major influence on the evolution of gypsy-type retrotransposons in Oryza species. Based on sequence data phylogenetic relationships among species of the O. officinalis complex were estimated. The data suggests that O. eichingeri is more closely related to the ancestral species of the complex.
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  • 72
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    International journal of primatology 21 (2000), S. 421-444 
    ISSN: 1573-8604
    Keywords: phylogenetics ; biogeography ; speciation ; Ateles ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We used the results of phylogenetic analyses of relationships among spider monkeys (Ateles) based on mitochondrial and nuclear DNA to investigate questions of their evolutionary origins and speciation mechanisms. We employed the concept of a local molecular clock to date nodes of interest (corresponding to hypothesized species and subspecies) in the various phylograms for comparison to hypothesized biogeographical events that might have affected speciation. We considered various mechanisms—Pleistocene refuge formation, riverine barriers, geological fluctuations, and ecological changes associated with these mechanisms—for their contribution to speciation in Ateles. Most speciation among the various species of Ateles occurred during the middle to late Pliocene, suggesting that Pleistocene refuge formation was not a key speciation mechanism. However, it is likely that the genetic structure of populations of Ateles was modified to some extent by refuge formation. Additionally, riverine barriers do not seem to interrupt gene flow significantly among Ateles. No river formed a barrier among species of Ateles, with the exception of the lower Amazon and possibly some of the black-water rivers draining the Guianan highlands. Large-scale geographic changes associated with the continued rise of the eastern and western cordilleras of the northern Andes and associated changes in habitat were the most important causes of speciation in Ateles. The various factors that modify genetic structure in Ateles are important to consider in order to protect endangered primate genera in the Neotropics.
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  • 73
    ISSN: 1573-8604
    Keywords: vocalization ; sexual advertisement ; predator advertisement ; taxonomy ; evolution ; mouse lemur ; primate ; Madagascar
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Advertisement calls are often important noninvasive tools for discriminating cryptic species and for assessing specific diversity and speciation patterns in nature. We investigated the contribution of these calls to uncover specific diversity in nocturnal Malagasy lemurs. We compared sexual advertisement and predator advertisement calls of two mouse lemur species, western gray and eastern rufous mouse lemurs (Microcebus murinus and M. rufus, respectively) living in two contrasting habitats (dry deciduous vs. rain forest), and analyzed them statistically. Both species emitted several highly variable whistle calls in the context of predator-avoidance. Intrapopulation variation was high and overlapped interspecific variation. Sexual advertisement calls, given in the mating context, displayed a totally distinct, species-specific acoustic structure. Whereas gray mouse lemurs produced rapidly multifrequency modulated, long trill calls, rufous mouse lemurs gave slowly frequency-modulated short chirp calls. Our results suggest specific status for gray and rufous mouse lemurs and indicate the importance of predation and social needs in shaping vocal communication.
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  • 74
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    Evolutionary ecology 14 (2000), S. 665-692 
    ISSN: 1573-8477
    Keywords: disease ; evolution ; frequency-dependent selection ; genetic diversity ; life history ; lifespan ; polymorphism ; reproduction rate ; resistance ; specificity ; virulence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Pathogens and parasites can be strong agents of selection, and often exhibit some degree of genetic specificity for individual host strains. Here we show that this host–pathogen specificity can affect the evolution of host life history traits. All else equal, evolution should select for genes that increase individuals' reproduction rates or lifespans (and thus total reproduction per individual). Using a simple host–pathogen model, we show that when the genetic specificity of pathogen infection is low, host strains with higher reproduction rates or longer lifespans drive slower-reproducing or shorter-lived host strains to extinction, as one would expect. However, when pathogens exhibit specificity for host strains with different life history traits, the evolutionary advantages of these traits can be greatly diminished by pathogen-mediated selection. Given sufficient host–pathogen specificity, pathogen-mediated selection can maintain polymorphism in host traits that are correlated with pathogen resistance traits, despite large intrinsic fitness differences among host strains. These results have two important implications. First, selection on host life history traits will be weaker than expected, whenever host fitness is significantly affected by genotype-specific pathogen attack. Second, where polymorphism in host traits is maintained by pathogen-mediated selection, preserving the genetic diversity of host species may require preserving their pathogens as well.
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  • 75
    ISSN: 1615-6110
    Keywords: Cladistics ; evolution ; Illiciales ; Illicium ; ITS ; star anise
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sequences of the internal transcribed spacers (ITS) of nuclear ribosomal DNA were determined for 15 species ofIllicium (Illiciaceae) to examine phylogenetic relationships. The ITS trees show a major dichotomy between the two North American species (I. floridanum andI. parviflorum) and the remaining east Asian species. This suggests that the existing division between two sections (sect.Illicium and sect.Cymbostemon) ofIllicium based on tepal characters in unnatural. The ITS phylogeny shows congruence with palynology: of the species examined, the three species (I. angustisepalum, I. anisatum andI. fargesii) from sect.Illicium that possess trizonocolpate pollen consistently form a clade, although nesting within a clade consisting of the species of sect.Cymbostemon, which generally have trisyncolpate pollen. The low ITS sequence divergence and the close relationship among east Asian species suggest a recent diversification of this group of species or an unusual slowdown of sequence mutations.
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  • 76
    ISSN: 1615-6110
    Keywords: In situ hybridization ; evolution ; NOR ; rDNA ; Muscari
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the subgenusLeopoldia of the genusMuscari, M. comosum is an exceptional species because it presents the most asymmetrical karyotype of the group and because its only active NOR is located in the fifth chromosome pair, while in the other species it is located in the first or second chromosome pairs (all the species have 2n = 18 chromosomes). SinceM. comosum has a derived karyotype different from those of the other species of the group, the resulting question is whether, in the first and second chromosome pair of this species, ribosomal cistrons persist. Observations after fluorescence in situ hybridization (FISH) using rDNA probes indicate that there are indeed ribosomal loci in the first and second chromosome pairs of this species, although these loci are inactive with respect to nucleolus organization. The location of rDNA regions in another three species of the same genus (M. atlanticum, M. dionysicum andM. matritensis) provides a basis for examining the significance of these findings in relation to the evolution of the ribosomal loci in this genus. Our observations indicate that in the genusMuscari, the largest sites for rRNA genes are not necessarily active, and, therefore, the activation of these regions is not related to the number of copies but to a specific regulation mechanism.
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    Journal of economics 71 (2000), S. 1-30 
    ISSN: 1617-7134
    Keywords: evolution ; local interaction ; cooperation ; prisoner's dilemma ; Markov processes ; C78
    Source: Springer Online Journal Archives 1860-2000
    Topics: Economics
    Notes: Abstract We study local interaction within a population located on a connected graph. Subjects engage in several bilateral interactions during each round in a generalized Prisoners' Dilemma (PD). In each round of play one randomly selected player gets the possibility to update the action he plays in this PD. All individuals use the update rule “Win Cooperate, Lose Defect,” a multi-player variant of Tit-for-Tat. Theoretical results on the set of stable states of the associated dynamics are provided for the cases with and without rare mutations. Simulations provide insight into the probability distribution over these stable states. In both cases a rather high probability is assigned to stable states with a moderate level of cooperation implying that dominated strategies are used. Furthermore, the probability of reaching the stable state with Nash equilibrium play is small.
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  • 78
    ISSN: 1573-5028
    Keywords: evolution ; C4 plant ; maize ; ribulose-bisphosphate carboxylase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The small subunit of ribulose-bisphosphate carboxylase (Rubisco), encoded by rbcS, is essential for photosynthesis in both C3 and C4 plants, even though the cell specificity of rbcS expression is different between C3 and C4 plants. The C3 rbcS is specifically expressed in mesophyll cells, while the C4 rbcS is expressed in bundle sheath cells, and not mesophyll cells. Two chimeric genes were constructed consisting of the structural gene encoding β-glucuronidase (GUS) controlled by the two promoters from maize (C4) and rice (C3) rbcS genes. These constructs were introduced into a C4 plant, maize. Both chimeric genes were specifically expressed in photosynthetic organs, such as leaf blade, but not in non-photosynthetic organs. The expressions of the genes were also regulated by light. However, the rice promoter drove the GUS activity mainly in mesophyll cells and relatively low in bundle sheath cells, while the maize rbcS promoter induced the activity specifically in bundle sheath cells. These results suggest that the rice promoter contains some cis-acting elements responding in an organ-pecific and light-inducible regulation manner in maize but does not contain element(s) for bundle sheath cell-specific expression, while the maize promoter does contain such element(s). Based on this result, we discuss the similarities and differences between the rice (C3) and maize (C4) rbcS promoter in terms of the evolution of the C4 photosynthetic gene.
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  • 79
    ISSN: 1573-5036
    Keywords: evolution ; glutamine synthetase ; sequences ; subunit composition ; Trientalis europaea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Ion-exchange chromatography of extracts from Trientalis europaea L. leaf tissue have been shown to contain two distinct isoforms of glutamine synthetase (GS). However, analysis by Western blotting has shown that the first peak to elute contains a mixture of large and small GS subunits, whilst the second peak is comprised entirely of a smaller subunit. This is contrary to the widespread assumptions concerning plant GS biochemistry. Isolation of intact chloroplasts and subsequent extraction of GS, followed by ion-exchange chromatography, has shown that the first peak to elute contains a large subunit, and the second chloroplastic peak is composed entirely of the small subunit. This smaller subunit may be present due to it being encoded by a separate chloroplastic GS gene, or it may be present as a product of post-translational modification. DNA sequencing has been used to try and determine which of these may be occurring. The three partial DNA sequences (505 nucleotides) we have obtained from T. europaea have been compared with 64 other sequences available on the NCBI database, which have mainly been obtained from crop species. Neighbour joining and parsimony analysis (1000 bootstrap) has shown support (∼30%) for the separation of plant GS from all other phyla. Within the plant phylum, there is total support for the separation of chloroplastic and cytosolic GS (100%), whilst the cytosolic sequences divide further into monocot and dicot species (77% support by NJ). Further subgroups of plants from the same families is also suggested. This is consistent with previous work containing fewer, but longer (∼1000 nucleotides) GS sequences. The addition of GS sequences obtained from wild plant species, such as T. europaea, to the large amount of information already available on the database, will permit a better understanding of the evolution of this important enzyme.
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  • 80
    ISSN: 1573-5079
    Keywords: anatomy ; C3 and C4 photosynthesis ; Chenopodiaceae ; cotyledon ; deserts ; evolution ; leaf ; Salsola
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Most species of the genus Salsola (Chenopodiaceae) that have been examined exhibit C4 photosynthesis in leaves. Four Salsola species from Central Asia were investigated in this study to determine the structural and functional relationships in photosynthesis of cotyledons compared to leaves, using anatomical (Kranz versus non-Kranz anatomy, chloroplast ultrastructure) and biochemical (activities of photosynthetic enzymes of the C3 and C4 pathways, 14C labeling of primary photosynthesis products and 13C/12C carbon isotope fractionation) criteria. The species included S. paulsenii from section Salsola, S. richteri from section Coccosalsola, S. laricina from section Caroxylon, and S. gemmascens from section Malpigipila. The results show that all four species have a C4 type of photosynthesis in leaves with a Salsoloid type Kranz anatomy, whereas both C3 and C4 types of photosynthesis were found in cotyledons. S. paulsenii and S. richteri have NADP- (NADP-ME) C4 type biochemistry with Salsoloid Kranz anatomy in both leaves and cotyledons. In S. laricina, both cotyledons and leaves have NAD-malic enzyme (NAD-ME) C4 type photosynthesis; however, while the leaves have Salsoloid type Kranz anatomy, cotyledons have Atriplicoid type Kranz anatomy. In S. gemmascens, cotyledons exhibit C3 type photosynthesis, while leaves perform NAD-ME type photosynthesis. Since the four species studied belong to different Salsola sections, this suggests that differences in photosynthetic types of leaves and cotyledons may be used as a basis or studies of the origin and evolution of C4 photosynthesis in the family Chenopodiaceae.
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  • 81
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    Genetic resources and crop evolution 47 (2000), S. 385-393 
    ISSN: 1573-5109
    Keywords: Citrullus lanatus ; cluster analysis ; evolution ; morphology ; watermelon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Morphological data recorded from field trials using Citrullus lanatus germplasm collected in Namibia were used to analyse and compare the various morphotypes of this species. The experiment comprised wild types and local landraces as well as commercial cultivars. Cluster analysis supported the indigenous classification system used in Namibia, in which Citrullus types are distinguished based on gross morphology, ecology and usage and grouped into seed, cooking and fresh-eating (watermelon) types. Commercial watermelon cultivars formed a distinct cluster. Wide variation was found within the local types whereas the genetic basis of the commercial type appears to be narrow. The commercial cultivars were most closely related to local watermelon types and more distantly related to the wild types, whereas the cooking melons form an intermediate group.
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  • 82
    ISSN: 1573-5117
    Keywords: reflecting organ ; upper lip ; Myodocopa ; chemical cues ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Multifunctions of the upper lip in a bioluminescent myodocopid Vargula hilgendorfii were studied by video observation and histological method. The localization of luciferin and luciferase gland cells within the upper lip was partly successful. Two long protrusions of the upper lip, both of V. hilgendorfii and a non-luminescent species of the same family, immediately anterior to the mouth, were found to show very flexible movement especially while eating, as if smearing on the food surface a secretion from the protrusions (glands), which may support the hypothesized secretion of digestive enzymes from the upper lip. This hypothesis is further supported by the new finding of a pair of ducts which connect the basal part of the upper lip with the posterior digestive duct (stomach). Comparative studies of V. hilgendorfii with several sympatric non-luminescent species of the same family have also revealed that it has a characteristic reflecting organ immediately posterior to the anus. It is a conical small protrusion, as if dangling from the ventral edge of the abdomen at the apex of the cone. It is observable only in live specimens, when the furca, which is located outwardly to the organ, is sufficiently transparent. When illuminated, the reflecting organ reflects the distinct light. The diameter of the mirror (chemical composition provisionally analyzed) is about 6–8% of the carapace length. The organ develops from the very first stage of its ontogeny without reference to sex, which suggests that the function may be related to intraspecific signaling or predatory deterrence.
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  • 83
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    Hydrobiologia 419 (2000), S. 31-63 
    ISSN: 1573-5117
    Keywords: morphology ; ontogeny ; Ostracoda ; evolution ; fifth limb ; crustacean phylogeny
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The chaetotaxy (shape, structure and distribution of setae) of appendages and valve allometry during the post embryonic ontogeny of the cyprididine ostracod Eucypris virens are described. It is shown that the basic ontogenetic development of E. virens is very similar to that of other species of the family Cyprididae. During ontogeny, the chaetotaxy shows continual development on all podomeres of the limbs with the exception of the last podomere on the antennulae. The long setae on the exopodite and protopodite of the antennae have a natatory function until the actual natatory setae develop in later instars. Aesthetascs (presumed chemoreceptors) ya and y3 are the first to develop and may have an important function in the first instars. Cyprididae require a pediform limb in the posterior of the body presumably to help them to attach to substrates and this is reflected by the pediform nature of one limb at all times throughout all instars. This study has also shown that the fifth limb is most probably of thoracic origin and hence ostracods have only one pair of maxillae.
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  • 84
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    Hydrobiologia 419 (2000), S. 7-11 
    ISSN: 1573-5117
    Keywords: morphology ; palaeontology ; ecology ; genetics ; Ostracoda ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Morphology, palaeontology, genetics and ecology are the main scientific domains contributing theories, concepts and new data to evolutionary biology. Ostracods are potentially very good model organisms for evolutionary studies because they combine an excellent fossil record with a wide extant distribution and, therefore, allow studies on both patterns and processes leading to extant diversity. This preface provides an overview of the 15 contributions to the present volume and concludes that this set of papers supports the claim that ostracod studies are situated in all main evolutionary domains.
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  • 85
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    Hydrobiologia 417 (2000), S. 91-99 
    ISSN: 1573-5117
    Keywords: evolution ; phylogeny ; larval characters ; morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The plesiomorphic mode of crustacean development is widely accepted to be via a larva called the nauplius. Extant taxa like the Cephalocarida, Branchiopoda, Ostracoda, Mystacocarida, Copepoda, Cirripedia, Ascothoracida, Facetotecta, Euphausiacea and Penaeidea hatch from an egg as a free-living nauplius. Other crustaceans show an embryonic phase of development suggestive of a naupliar organization. Several features of the nauplius larva have been proposed as diagnostic characters for the Crustacea: a median (nauplius) eye; at least three pairs of head appendages (antennules, antennae, mandibles); a posteriorly directed fold (the labrum) extending over the mouth and a cephalic (nauplius) shield. The relationship between trilobite protaspis with at least four appendages and the crustacean nauplius remains unclear, but reports of a copepod orthonauplius with four appendages are rejected. Swimming is suggested to represent the underived mode of locomotion for the crustacean nauplius, and that naupliar swimming directly results in naupliar feeding which also is underived.
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  • 86
    ISSN: 1573-5117
    Keywords: population genetics ; evolution ; allozymes ; DNA ; marine genetics ; Acanthaster planci
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The basic assumptions that widespread marine species should show little spatial variation in genetic structure, given their high potential for dispersal on ocean currents, is being questioned. This has taken some time because there are few studies of widespread marine species over oceanic scales, few data sets that have the high density of sampling required for the detection of fine population structure, and there is little incentive to look further if initial analyses suggest the expected result. The interpretation of the population genetic structure of crown-of-thorns starfish (Acanthaster planci) has been found to vary considerably depending on the sample set included in the analyses and on the method of analysis used. Scatter plots of genetic distance or θ, and spatial autocorrelation approaches gave markedly different results ranging from no structure to isolation by distance. Only visual examination of maps of patterns of variation in allele variation first detected that crown-of-thorns starfish occupy large regions with little between population differentiation, but between which there are markedly higher levels of differentiation. These findings highlight the care required in interpreting population structure, particularly where there are few sample points. Many marine species may have population structures where sharp genetic disjunctions, not associated with any obvious environmental boundaries, separate regions of relative genetic homogeneity. Such population structures are very different from those traditionally assumed and are not yet understood. Further advances in understanding the genetic structure of marine species will demand an iterative approach where a greater number of samples are collected over particular regions identified by earlier interpretations.
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  • 87
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    Hydrobiologia 420 (2000), S. 15-27 
    ISSN: 1573-5117
    Keywords: phylogeny ; evolution ; allozymes ; rDNA ; DNA sequence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The first application of molecular systematics to sponges was in the 1980s, using allozyme divergence to dis-criminate between conspecific and congeneric sponge populations. Since this time, a fairly large database has been accumulated and, although the first findings seemed to indicate that sponge species were genetically more divergent than those of other marine invertebrates, a recent review of the available dataset indicates that levels of interspecific gene identities in most sponges fall within the normal range found between species of other invertebrates. Nevertheless, some sponge genera have species that are extremely divergent from each other, suggesting a possible polyphyly of these genera. In the 1990s, molecular studies comparing sequences of ribosomal RNA have been used to reappraise the phylogenetic relationships among sponge genera, families, orders and classes. Both the 18S small subunit and the 28S large subunit rRNA genes have been sequenced (41 complete or partial and 75 partial sequences, respectively). Sequences of 18S rRNA show good support for Porifera being true Metazoa, but they are not informative for resolving relationships among genera, families or orders. 28S rRNA domains D1 and D2 appear to be more informative for the terminal nodes and provide resolution for internal topologies in sufficiently closely related species, but the deep nodes between orders or classes cannot be resolved using this molecule. Recently, a more conserved gene, Hsp70, has been used to try to resolve the relationships in the deep nodes. Metazoan monophyly is very well supported. Nevertheless, the divergence between the three classes of Porifera, as well as the divergence between Porifera, Cnidaria and Ctenophora, is not resolved. Research is in progress using other genes such as those of the homeodomain, the tyrosine kinase domain, and those coding for the aggregation factor. For the moment the dataset for these genes is too restricted to resolve the phylogenetic relationships of these phyla. However, whichever the genes, the phylogenies obtained suggest that Porifera could be paraphyletic and that the phylogenetic relationships of most of the families and orders of the Demospongiae have to be reassessed. The Calcarea and Hexactinellida are still to be studied at the molecular level.
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  • 88
    ISSN: 1573-5133
    Keywords: Cyprinidae ; piscivores ; prey fish ; small barbs ; species flock ; evolution ; speciation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The endemic cyprinid species flock in Lake Tana consists of 15 species of large hexaploid barbs, eight of which are piscivorous. Previously, it was assumed that all piscivores preyed on the same small barb species, Barbus trispilopleura. In this paper we present a description of morphology and ecology of a new abundant small barb species, Barbus tanapelagius sp. nova (holotype RMNH 33731) from Lake Tana, Ethiopia, which appears to be the major prey species for the large pelagic piscivorous barbs. B. tanapelagius differs clearly in morphology from the other 3 small, diploid Barbus species known from Lake Tana, B. trispilopleura Boulenger, 1902, B. humilis Boulenger, 1902 and B. pleurogramma Boulenger, 1902. Conspicuous differences are its elongated body, large eye diameter, prominent and hooked lower jaw contour and colouration. Preliminary data suggest that B. tanapelagius also differs ecologically from the other small Barbus spp. by its pelagic, strictly zooplanktivorous feeding and its occurrence mainly in the deeper, offshore waters. The other small Barbus species are most probably largely benthic feeders and dominant in the shallow inshore waters. Previous views about the evolution of the present 8 endemic piscivorous large barb species therefore require reconsideration, as the present paper shows a more complex scenario including several prey species.
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  • 89
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    Hydrobiologia 420 (2000), S. 55-62 
    ISSN: 1573-5117
    Keywords: chromosomes ; evolution ; nucleolar organizer region
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The number of cytogenetic studies of marine fish has increased in recent years. Fish groups, such as Perciformes, which comprises many of the extant marine teleosts of economic importance, show little divergence in chromosome number and most species display a diploid number of 48 acrocentric chromosomes. In the Serranidae, Sparidae, Sciaenidae (Perciformes) and Mugilidae (Mugiliformes) small chromosome variations are restricted to subtle heterochromatin or nucleolar organizer region (NOR) modifications. There appears to exist a strict relationship between both absence of geographic barriers throughout the marine environment and high mobility of these animals (eggs, larvae, or adults), with a rarity of chromosome rearrangement at the macrostructural level. Moreover, a cellular homeostasis might also be important to karyotype maintenance among these fishes, limiting changes in the chromosome complement to cryptic chromosome rearrangements. Other groups, such as Blenniidae, Gobiidae and Scorpaenidae, for instance, show more extensive chromosome diversity, which is probably related to limited mobility. Numerical and structural chromosome polymorphisms and several sexual chromosome systems are recurrent among these fishes. A wide karyotypic diversification also characterizes the Tetraodontiformes, an interesting fish group with peculiar morphological, physiological and ecological characteristics.
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  • 90
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    Environmental biology of fishes 57 (2000), S. 443-449 
    ISSN: 1573-5133
    Keywords: parental care ; feeding behaviour ; evolution ; trade-off ; individual differences ; fish
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The function of the fin digging behaviour in increasing food availability for the offspring was analysed in the convict cichlid, Cichlasoma (Archocentrus) nigrofasciatum. Consistent individual differences in the frequency of fin digging were found in the parental fish. Examination of the gastrointestinal tract of young revealed that higher frequency of parental fin digging was associated with higher consumption of large and more profitable prey (Diptera larvae), which inhabited deep horizons of the bottom substrate and possibly were difficult to access without parental assistance. Thus, parental fin digging was initially associated with a significant increase of the offspring growth rate. However, at later brood intervals, when parental care ceased, the young of the high-digging parents were characterised by a poorer consumption of small larvae that were most accessible for them without parental aid and represented an increasingly more important component of their ration than large larvae. Offspring of the low-digging parents, on the other hand, presumably as a result of their individual experience, showed a considerably better consumption of small larvae, increasing their growth rate. As a consequence, prior parental fin digging did not affect the offspring body size after independence. Thus, there exist pronounced individual differences and alternative parental styles in the convict cichlid.
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  • 91
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    Plant molecular biology 42 (2000), S. 151-166 
    ISSN: 1573-5028
    Keywords: evolution ; homeodomain protein ; knox gene ; meristem
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Knotted-like homeobox (knox) genes constitute a gene family in plants. Class I knox genes are expressed in shoot apical meristems, and (with notable exceptions) not in lateral organ primordia. Class II genes have more diverse expression patterns. Loss and gain of function mutations indicate that knox genes are important regulators of meristem function. Gene duplication has contributed to the evolution of families of homeodomain proteins in metazoans. We believe that similar mechanisms have contributed to the diversity of knox gene function in plants. Knox genes may have contributed to the evolution of compound leaves in tomato and could be involved in the evolution of morphological traits in other species. Alterations in cis-regulatory regions in some knox genes correlate with novel patterns of gene expression and distinctive morphologies. Preliminary data from the analysis of class I knox gene expression illustrates the evolution of complex patterns of knox expression is likely to have occurred through loss and gain of domains of gene expression.
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  • 92
    ISSN: 1573-5028
    Keywords: angiosperm ; development ; evolution ; fern ; gymnosperm ; MADS-box gene
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Evolutionary developmental genetics (evodevotics) is a novel scientific endeavor which assumes that changes in developmental control genes are a major aspect of evolutionary changes in morphology. Understanding the phylogeny of developmental control genes may thus help us to understand the evolution of plant and animal form. The principles of evodevotics are exemplified by outlining the role of MADS-box genes in the evolution of plant reproductive structures. In extant eudicotyledonous flowering plants, MADS-box genes act as homeotic selector genes determining floral organ identity and as floral meristem identity genes. By reviewing current knowledge about MADS-box genes in ferns, gymnosperms and different types of angiosperms, we demonstrate that the phylogeny of MADS-box genes was strongly correlated with the origin and evolution of plant reproductive structures such as ovules and flowers. It seems likely, therefore, that changes in MADS-box gene structure, expression and function have been a major cause for innovations in reproductive development during land plant evolution, such as seed, flower and fruit formation.
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  • 93
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    Plant molecular biology 42 (2000), S. 181-194 
    ISSN: 1573-5028
    Keywords: actinorhiza ; endomycorrhizae ; evolution ; Frankia ; haemoglobins ; nod factors ; nodulation ; phylogeny ; rhizobia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In this review we will first describe the different steps leading to nodule formation, and these will be compared with processes of non-symbiotic plant development and growth. In general, aspects of both actinorhizal as well as rhizobial symbiosis are described, but in several cases, the emphasis will be on the Rhizobium-legume symbiosis because more knowledge of this system is available. Subsequently, the phylogeny of nodulating plants is described and a comparison is made between several aspects of legume and actinorhizal nodulation. At the end of this paper the relationship between nodule symbiosis and endomycorrhizal symbiosis is described, and it is discussed to what extent the development of root nodules involves unique properties, or whether processes and genes have been recruited from common plant development and the endomycorrhizal symbiosis.
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  • 94
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    Journal of bioenergetics and biomembranes 32 (2000), S. 227-236 
    ISSN: 1573-6881
    Keywords: NDP kinase ; subunit interaction ; quaternary structure ; evolution ; mixed oligomers ; Dictyostelium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Physics
    Notes: Abstract Nucleoside (NDP) diphosphate kinases are oligomeric enzymes. Most are hexameric, but somebacterial enzymes are tetrameric. Hexamers and tetramers are constructed by assemblingidentical dimers. The hexameric structure is important for protein stability, as demonstratedby studies with natural mutants (the Killer-of-prune mutant ofDrosophila NDP kinase andthe S120G mutant of the human NDP kinase A in neuroblastomas) and with mutants obtainedby site-directed mutagenesis. It is also essential for enzymic activity. The function of the tetrameric structure is unclear.
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  • 95
    ISSN: 1573-6849
    Keywords: evolution ; genome ; Gossypium ; polyploidization ; repetitive element ; retrotransposon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Retrotransposons constitute a ubiquitous and dynamic component of plant genomes. Intragenomic and intergenomic comparisons of related genomes offer potential insights into retrotransposon behavior and genomic effects. Here, we have used fluorescent in-situ hybridization to determine the chromosomal distributions of a Ty1-copia-like retrotransposon in the cotton AD-genome tetraploid Gossypium hirsutum and closely related putative A- and D-genome diploid ancestors. Retrotransposon clone A108 hybridized to all G. hirsutum chromosomes, approximately equal in intensity in the A- and D-subgenomes. Similar results were obtained by hybridization of A108 to the A-genome diploid G. arboreum, whereas no signal was detected on chromosomes of the D-genome diploid G. raimondii. The significance and potential causes of these observations are discussed.
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  • 96
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    Genetica 109 (2000), S. 105-111 
    ISSN: 1573-6857
    Keywords: Drosophila ; evolution ; heterochromatin ; Y chromosome
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Y chromosome evolution is characterized by the expansion of genetic inertness along the Y chromosome and changes in the chromosome structure, especially the tendency of becoming heterochromatic. It is generally assumed that the sex chromosome pair has developed from a pair of homologues. In an evolutionary process the proto-Y-chromosome, with a very short differential segment, develops in its final stage into a completely heterochromatic and to a great extends genetically eroded Y chromosome. The constraints evolving the Y chromosome have been the objects of speculation since the discovery of sex chromosomes. Several models have been suggested. We use the exceptional situation of the in Drosophila mirandato analyze the molecular process in progress involved in Y chromosome evolution. We suggest that the first steps in the switch from a euchromatic proto-Y-chromosome into a completely heterochromatic Y chromosome are driven by the accumulation of transposable elements, especially retrotransposons inserted along the evolving nonrecombining part of the Y chromosome. In this evolutionary process trapping and accumulation of retrotransposons on the proto-Y-chromosome should lead to conformational changes that are responsible for successive silencing of euchromatic genes, both intact or already mutated ones and eventually transform functionally euchromatic domains into genetically inert heterochromatin. Accumulation of further mutations, deletions, and duplications followed by the evolution and expansion of tandem repetitive sequence motifs of high copy number (satellite sequences) together with a few vital genes for male fertility will then represent the final state of the degenerated Y chromosome.
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  • 97
    ISSN: 1573-7217
    Keywords: adjuvant chemotherapy ; breast cancer ; decision-making ; treatment preference ; decision board instrument
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose.To examine the effects of framing of outcome and probabilities of cancer occurrence on the treatment preference which breast cancer patients indicate for hypothetical patient scenarios. Methods.A modified version of the Decision Board Instrument (Levine et al. 1992) was administered to 35 breast cancer patients with past ACT experience. Patients expressed their choice regarding ACT for six scenarios which were characterized by either negative or positive framing of outcome and by one of the three levels of probability of recurrence (high, medium, low). Results.The framing had no influence on ACT choices over all three probability levels. The majority chose ACT for high and medium risk and one third switched from ACT to No ACT in the low-risk condition. This switch was statistically significant. Conclusion.Hypothetical treatment decisions against ACT occur only when the probability of recurrence is low and the benefit of ACT is small. This finding for patients with past experience of ACT is similar to those reported for other oncological patient groups still in treatment.
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  • 98
    ISSN: 1573-7217
    Keywords: breast cancer ; metastasis ; liver metastasis ; surgical procedure ; hepatectomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We have performed a retrospective study to evaluate whether surgical treatment is beneficial in patients with hepatic metastases from breast cancer. Between September 1985 and September 1998, 25 patients with hepatic metastases (14 solitary and 11 multiple), eight of whom had extrahepatic metastases, underwent hepatectomy. All of the detectable liver metastasis were resected in all of the cases. There were no severe postoperative complications. All but one of the patients received adjunctive polychemotherapy after the hepatectomy. After the hepatectomy, recurrent tumors were detected in 18 of the patients, being located in the liver in 12 (67%) of them. Overall, however, hepatectomy ensured that the liver was clinically recurrence-free for a median of 24 months (range 2–132 months). Eleven patients died of recurrent tumors, two died of other causes and the remaining 12 are currently alive. The 2- and 5-year cumulative survival rates after hepatectomy were 71% and 27%, respectively, and the median survival duration was 34.3±3.2 months, much better than the period of 8.5 months for another series of patients treated with standard or non-surgical therapies at our institution. The number and the size of hepatic metastases, the interval between treatment of the primary lesion and hepatectomy, and the existence of extrahepatic metastasis were not adverse prognostic factors. In conclusion, our data, although limited and highly selective, suggest that surgical treatment of hepatic metastases from breast cancer may prolong survival in certain subgroups of patients to a greater extent than standard or non-surgical therapies.
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  • 99
    ISSN: 1573-7217
    Keywords: apoptosis ; breast cancer ; continuous variables statistical analysis ; cytokeratins ; multiple correspondence analysis ; prognosis ; tissue cytosol ; tissue polypeptide antigen (TPA)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Apoptosis is associated with caspase-mediated proteolysis of Type I (K18 and K19) cytokeratins. We previously showed a positive association between the levels of tissue polypeptide antigen (TPA), that recognizes cytokeratins K8, K18, and K19 fragments, and induced apoptosis in breast cancer cell lines. The aim of the present study was to evaluate the interrelationships between TPA, steroid receptors, and p53, and their joint prognostic role in node-negative breast cancer patients not treated with adjuvant therapies. Age and pT were also considered since they are known prognostic factors. Five hundred and ninety-nine cases with N- breast cancer were evaluated (median follow-up: 60 months). TPA was measured by an immunoradiometric assay and p53 by an immuno-chemiluminescent assay in tumor cytosol. Multiple correspondence analysis was used to study the associations among variables. Their prognostic role (univariate analysis) and their joint effect (multivariate analysis) on RFS were investigated with Cox regression models. TPA showed a direct association with ER and PgR. Higher p53 values were weakly associated to low values of ER, PgR, and TPA. Younger age was related to low and intermediate values of ER and PgR and to low p53 values, while older age was related to high values of ER. Multivariate analysis showed a significant prognostic impact for pT, age, ER, and TPA. Among the interactions considered clinically relevant, only that between ER and age was found. RFS estimated values were poorer in cases with lower than in those with higher TPA values, both in patients expected to have a poor (pT2, young age, low ER) and a better prognosis (pT1, older age, high ER). From the findings of the present study we can draw the following conclusions: The relationship of TPA with prognosis gives an additional contribution to pT, age, and steroid receptors in N- breast cancer; TPA may be considered the first marker of apoptosis measured with a fully standardized quantitative method in tumor cytosol and could be evaluated in prognostic indexes including markers related to different biological mechanisms.
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  • 100
    ISSN: 1573-7217
    Keywords: reversal ; paclitaxel ; resistance ; P-glycoprotein ; breast cancer ; valspodar ; apoptosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Paclitaxel (Taxol®) kills tumor cells by inducing both cellular necrosis and apoptosis. A major impediment to paclitaxel cytotoxicity is the establishment of multidrug resistance whereby exposure to one chemotherapeutic agent results in cross-resistance to a wide variety of other drugs. For example, selection of MCF-7 breast cancer cells for resistance to doxorubicin (MCF-7ADR cells) results in cross-resistance to paclitaxel. This appears to involve the overexpression of the drug transporter P-glycoprotein which can efflux both drugs from tumor cells. However, MCF-7ADR cells possess a deletion mutation in p53 and have considerably reduced levels of the Fas receptor, Fas ligand, caspase-2, caspase-6, and caspase-8, suggesting that paclitaxel resistance may also stem from a bona fide block in paclitaxel-induced apoptosis in these cells. To address this issue, we examined the ability of the P-glycoprotein inhibitor valspodar to restore paclitaxel accumulation, paclitaxel cytotoxicity, and paclitaxel-induced apoptosis. Compared to drug sensitive MCF-7 cells, MCF-7ADR cells accumulated 〉6-fold less paclitaxel, were approximately 100-fold more resistant to killing by the drug, and were highly resistant to paclitaxel-induced apoptosis. In contrast, MCF-7ADR cells pretreated with valspodar were indistinguishable from drug-sensitive cells in their ability to accumulate paclitaxel, in their chemosensitivity to the drug, and in their ability to undergo paclitaxel-induced apoptosis. Valspodar, by itself, did not affect these parameters. This suggests that the enhancement of paclitaxel toxicity in MCF-7ADR cells involves a restoration of apoptosis and not solely through enhanced drug-induced necrosis. Morever, it appears that changes in the levels/activity of p53, the Fas receptor, Fas ligand, caspase-2, caspase-6, or caspase-8 activity have little effect on paclitaxel-induced cytotoxicity and apoptosis in human breast cancer cells.
    Type of Medium: Electronic Resource
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