Library

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1995-1999  (1,034)
  • 1999  (1,034)
  • General Chemistry  (750)
  • breast cancer  (126)
  • Life and Medical Sciences  (96)
  • Amino acids  (73)
  • Nuclear reactions
Material
Years
  • 1995-1999  (1,034)
Year
Keywords
  • 1
    ISSN: 1436-2813
    Keywords: Key Words: chemoendocrine therapy ; pure antiestrogen ; 5-fluorouracil ; nude mouse ; breast cancer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1436-2813
    Keywords: chemoendocrine therapy ; pure antiestrogen ; 5-fluorouracil ; nude mouse ; breast cancer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The antitumor effects of an experimental chemoendocrine therapy combining a new pure antiestrogen ICI 182780 and 5-fluorouracil (5-FU) were studied on MCF-7 human breast cancer cells implanted in nude mice. ICI 182780 had a dose-dependent antitumor activity, which was potentiated by the concomitant use of 5-FU. When compared with the control group, the estrogen receptor (ER) level in the ICI 182780 group was lower and that in the combination group was markedly lower. Cell cycle analysis by flow cytometry (FCM) resulted in a lower percentage of S-phase cells (%S) in the treated mice. No significant difference was observed in the 5-FU concentrations in tumor cells, while the 5-FU content in RNA was significantly higher in the combination group. The changes in free thymidylate synthetase (TS) concentration indicated TS synthesis after the administration of 5-FU to be more greatly suppressed in the combination group than in the 5-FU group. These results suggest that ICI 182780 and 5-FU exert their combination effect mainly on ER-positive cells, and that the suppression of TS synthesis in tumor cells and the potentiation of the 5-FU-induced metabolic dysfunction of RNA are thus involved in the mode of action of this combination therapy.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1569-8041
    Keywords: breast cancer ; old age ; vinorelbine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: Older patients with advanced breast cancer are less likely to receive chemotherapy than younger patients. Vinorelbine is an attractive alternative in this setting because of its clinical activity and low frequency of side effects. This multicenter, phase II trial was designed to assess the safety and efficacy of intravenous vinorelbine as first-line therapy in women ≥60 years old. Patients and methods: Fifty-six women (median age, 72 years; range 60–84 years), with measurable advanced breast cancer and no prior chemotherapy for metastatic disease, were enrolled and included in the analysis. Vinorelbine 30 mg/m2 was administered weekly for 13 weeks and then every two weeks until development of progressive disease; doses were reduced or delayed to manage toxicity. Results: The objective response rate was 38% (95% confidence interval (95% CI): 24%–51%); median duration of response, nine months; median time to disease progression in all patients, six months. The major dose-limiting toxicity was hematologic, which led to a median dose intensity of 20.6 mg/m2/week. Grade 3–4 nonhematologic toxicity consisted of asthenia (7%); nausea and generalized pain (5%); vomiting, chest pain, abdominal pain, and elevated AST (4%); fever, diarrhea, constipation, and injection site reaction (2%). Neurotoxicity and alopecia were grade 1–2 and relatively infrequent. Conclusions: Vinorelbine offers a promising alternative for the management of advanced breast cancer in elderly patients who are concerned about the subjective side effects of cytotoxic chemotherapy. The dose-limiting toxicity is neutropenia, which is readily managed with dose adjustment. Nonhematologic toxicity, including gastrointestinal side effects, is minimal. Randomized studies are warranted to compare the activity of vinorelbine with that of other regimens in elderly patients.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1438-2199
    Keywords: Amino acids ; RT/PCR ; Protooncogene ; ets-2
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Protooncogenes (PO) play a crucial role for brain biology and pathology. Only the concerted action of protooncogenes enables normal brain development. The reliable and sensitive quantification of brain PO is still holding centre stage in neurobiological research. The aim of our study was therefore the determination of PO in minute amounts of brain areas. For this purpose we decided to apply the most sensitive detection principle of competitive reverse transcriptase polymerase chain reaction using capillary electrophoresis and laser-induced fluorescence detection. We selected the PO ets-2 for our studies as this transcription factor was shown to be involved in neurodegenerative disease. As little as 10ng of total RNA each were extracted from 5 different regions of human postmortem brain and used in the assay system. Our results revealed that the ets-2 gene transcript was detectable at the atto-gram level in the brain (54.5 ± 17.7 ag/ 10 ng RNA in the occipital lobe, 34.2 ± 7.5 in temporal lobe, 40.2 ± 15.6 in the frontal lobe, 31.4 ± 15.7 in the cerebellum, and undetectably low in the parietal lobe). This is the first report at this sensitivity level providing neurobiology with a powerful analytical tool.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1438-2199
    Keywords: Amino acids ; Taurine ; Marathon ; Endurance exercise
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The sulphonated amino acid taurine increased significantly in the plasma of trained athletes after three endurance exercises of different duration and intensity, a 90 min run on a treadmill at 75% of an individual's VO2 peak, a Marathon, 42.2km and a 100km run, by 19%, 77% and 36%, respectively. Such results indicated that the speed at which the exercise is per formed, referred to as the intensity, rather than the duration of the exercise, correlated with the elevated taurine levels possibly indicating its release from muscle fibres. The plasma amino acid pool decreased significantly in relationship with the duration of the exercise, caused by their utilisation for glucogenesis. The possible sources of the increased plasma taurine are discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 17 (1999), S. 369-376 
    ISSN: 1438-2199
    Keywords: Amino acids ; Non-proteinogenic dipeptides ; Dehydrodipeptides ; Diastereoselectivity ; N-Boc-Dehydroamino acids ; Asymmetric hydrogenation ; Chiral rhodium catalysts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary N-Boc protected non-proteinogenic dipeptides with D,L-and L,L-configuration were prepared by catalytic asymmetric hydrogenation of the corresponding dehydrophenylalanyl-(L)-phenylalanine derivatives. The configuration of the new stereogenic centre depends first of all on the catalyst configuration and is less influenced by the substrate configuration. Diastereomeric excesses in the range of 80–96% de could be increased up to 99% by recrystallization. Analytical data of selected new compounds are given.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1438-2199
    Keywords: Amino acids ; Polyclonal antibodies ; Phosalone ; Immunodetection ; Hapten synthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Hapten synthesis for the production of specific insecticide phosalone polyclonal antibodies was carried out starting from an intermediate of the phosalone synthesis, 6-chloro-2-benzoxazolone1. Two haptens containing different spacers have been prepared: N-5-carboxypentyl-6-chloro-2-benzoxazolone7 and N-(2-oxo-3-aza-5-carboxypentyl)-6-chloro-2-benzoxazolone12. Each of these two haptens conjugated to bovine serum albumine (BSA) was used to immunize four rabbits. Immunoassays of phosalone were performed with ELISA using solid-phase bound hapten thyroglobulin conjugate and horseradish peroxidase labelled goat antirabbit IgG. The more sensitive response was observed when the antiserum obtained from the rabbit immunized with the hapten-BSA conjugate containing the N-2-oxo-3-aza-5-carboxypentyl spacer was in competition with the same hapten coupled to thyroglobulin. An identical response was obtained under the same conditions when using benzoxazolone instead of phosalone as competitor, showing a good recognition of the specific aromatic part of the organophosphate insecticide phosalone. Reduction of coating conjugate concentration (from 2 to 0.05μg/well) and also the use of heterologous coating protein instead of homologous did improve the sensitivity, resulting in a concentration of phosalone required to inhibit binding by 50% of 2 mg/l and a detection limit of 0.02 mg/l.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1438-2199
    Keywords: Amino acids ; Liver ; Hepatic damage ; Carbon tetrachloride
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The aims of the present study were to assess the changes of individual plasma amino acid levels in relation (1) to the severity of liver damage and (2) to the process of liver recovery. Acute liver injury was induced by an intragastric administration of CCl4 diluted in olive oil in doses of 2, 4 and /or 6 g of CCl4 per kg b.w. The control rats received olive oil only. Animals were sacrificed at 16, 24, 48 and 96 hours after treatment. The severity of liver injury was assessed by histological examination, by changes in ALT and AST in the blood plasma and by changes in liver weight. Statistical analysis was carried by ANOVA, p 〈 0.05 was considered significant. The Spearman rank correlation coefficient was used as a measure of the degree of linear relationship between variable and dose. In the period of the development of acute liver damage, i.e. at 16 and 24 hours after treatment, an increase in blood plasma amino acid levels and positive correlations with the dose of CCl4 were observed for most individual amino acids. The only exception was arginine which decreased in a dose dependent manner. At a phase of liver recovery, i.e. at 48 and 96 hours after CCl4 treatment, the concentrations of some individual amino acids decreased below the control values. The negative correlation with the dose of CCl4 occurred for taurine and isoleucine (at 48 hours) and taurine, threonine, valine, methionine, isoleucine and leucine (at 96 hours).
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1438-2199
    Keywords: Amino acids ; Alanine ; Fatty acids ; Glutamine and glutamate synthesis ; Glycerol and lactate metabolism ; Malate-aspartate shuttle ; Rabbit kidney-cortex tubules ; Renal gluconeogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In isolated rabbit renal cortical tubules, glucose synthesis from 1 mM alanine is negligible, while the amino acid is metabolized to glutamine and glutamate. The addition of 0.5 mM octanoate plus 2 mM glycerol induces incorporation of [U-14C]Alnine into glucose and decreases glutamine synthesis, whereas oleate and palmitate in the presence of glycerol are less potent than octanoate. Gluconeogenesis is also significantly accelerated when glycerol is substituted by lactate. In view of an increase in14CO2 fixation and elevation of both cytosolic and mitochondrial NADH/NAD+ ratios, the activation of glucose formation from alanine upon the addition of glycerol and octanoate is likely due to (i) stimulation of pyruvate carboxylation, (ii) increased availability of NADH for glyceraldehyde-3-phosphate dehydrogenase and (iii) elevation of mitochondrial redox state causing a diminished provision of ammonium for glutamine synthesis. The induction of gluconeogenesis in the presence of alanine, glycerol and octanoate is not related to cell volume changes. The results presented in this paper show the importance of free fatty acids and glycerol for regulation of renal gluconeogenesis from alanine. The possible physiological significance of the data is discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 16 (1999), S. 79-89 
    ISSN: 1438-2199
    Keywords: Amino acids ; Anti-neoplastic amino acids ; Purine and DNA synthesis inhibitors ; PRPP amido transferase and IMP dehydrogenase inhibitors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 4-Hydroxyproline di- and tri-peptides and N-cbz-hydroxypropylglycinamides were observed to be potent cytotoxic agents against the growth of suspended single cells, L-1210, Tmolt3, and HeLa-S3. The agents were not as potent against the growth of cultured solid tumor cells. Selected derivatives were investigated for their mode of action in Tmolt3 leukemia cells. The compounds selectively inhibited DNA synthesis at 50 and 100smM. The target site of action of the agents appeared to be the purinede novo pathway with marked inhibition of the activities of the two regulatory enzymes of the pathway, i.e. PRPP amido-transferase and IMP dehydrogenase. d[NTP] pools were reduced by the agents consistent with their overall reduction of DNA synthesis. Other marginally inhibited targets of the agents were r-RNA polymerase and TMP-kinase activities. The DNA molecule itself did not appear to be a target of these agents.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 11
    ISSN: 1438-2199
    Keywords: Amino acids ; Targeting ; Mitochondria ; Chloroplasts ; Cysteine synthase ; Transit peptide ; Transgenic plants ; Processing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cysteme synthase, the key enzyme for fixation of inorganic sulfide, catalyses the formation of cysteine from O-acetylserine and inorganic sulfide. Here we report the cloning of cDNAs encoding cysteine synthase isoforms fromArabidopsis thaliana. The isolated cDNA clones encode for a mitochondrial and a plastidic isoform of cysteine synthase (O-acetylserine (thiol)-lyase, EC 4.2.99.8), designated cysteine synthase C (AtCS-C, CSase C) and B (AtCS-B; CSase B), respectively.AtCS-C andAtCS-B, having lengths of 1569-bp and 1421-bp, respectively, encode polypeptides of 430 amino acids (∼45.8 kD) and of 392 amino acids (∼ 41.8 kD), respectively. The deduced amino acid sequences of the mitochondrial and plastidic isoforms exhibit high homology even with respect to the presequences. The predicted presequence of AtCS-C has a N-terminal extension of 33 amino acids when compared to the plastidic isoform. Northern blot analysis showed thatAtCS-C is higher expressed in roots than in leaves whereas the expression ofAtCS-B is stronger in leaves. Furthermore, gene expression of both genes was enhanced by sulfur limitation which in turn led to an increase in enzyme activity in crude extracts of plants. Expression of theAtCS-B gene is regulated by light. The mitochondrial, plastidic and cytosolic (Hesse and Altmann, 1995) isoforms of cysteine synthase ofArabidopsis are able to complement a cysteine synthasedeficient mutant ofEscherichia coli unable to grow on minimal medium without cysteine, indicating synthesis of functional plant proteins in the bacterium. Two lines of evidence proved thatAtCS-C encodes a mitochondrial form of cysteine synthase; first, import ofin vitro translation products derived from AtCS-C in isolated intact mitochondria and second, Western blot analysis of mitochondria isolated from transgenic tobacco plants expressing AtCS-C cDNA/c-myc DNA fusion protein.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 12
    ISSN: 1438-2199
    Keywords: Amino acids ; Non-proteinogenic optically active amino acids ; Dehydroamino acids ; Chiral rhodium catalysts ; Asymmetric hydrogenation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary (Z)-α-[(Benzyloxy)- or (tert.-butyloxy)carbonylamino]-β (thienyl)-or (furyl)-acrylic acids and their esters were prepared by known methods and hydrogenated to the corresponding optically active alanine derivatives with optical yields in the range of 58–93% ee using the cationic rhodium complex of “PROPRAPHOS”.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 13
    ISSN: 1438-2199
    Keywords: Amino acids ; L-Tryptophan ; Serum albumin ; Transport ; L-Tryptophan depletion ; α-Methyl-DL-tryptophan ; Analbuminemic rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The role of serum albumin in the transport of orally administered L-tryptophan (Trp) into rat tissues was examined using analbuminemic and Sprague-Dawley (SD) rats with and without a-methyl-DL-tryptophan (AMT)-induced Trp depletion. Trp was orally administered to rats 16h after AMT or 0.85% NaCl administration, when liver tryptophan 2,3-dioxygenase and protein synthetic activities in AMT-treated rats were similar to those of 0.85% NaCl-treated rats. After oral Trp administration, regardless of the presence or absence of Trp depletion, free serum Trp concentrations were similar in the analbuminemic and SD rats, while total serum Trp concentrations were lower in analbuminemic rats than in SD rats. Although liver, brain, and muscle Trp concentrations after oral Trp administration under Trp depletion were lower in analbuminemic rats than in SD rats, the ratio of the liver Trp concentration in analbuminemic rats to that in SD rats was smaller than that of the brain or muscle Trp concentration. These results suggest that variations in serum albumin levels could affect the transport of orally administered Trp into the liver of rats with Trp depletion.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 14
    ISSN: 1438-2199
    Keywords: Amino acids ; Tissue protein synthesis ; Stable isotope amino acids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The tracers L15N-proline and L(1-13C)-leucine were used to explore the synthesis of skin proteins in vivo in rabbits. They orally received a single dose containing an equimolecular mixture of L(1-13C)-leucine and L15N-proline. The changes in the amounts of these tracers in blood and skin were monitored for a total of 8 h. The data showed the appearance of the two tracers in blood within 15 min and their clearance in 8h. They were both rapidly (15 min) incorporated into skin proteins, but more proline was incorporated than leucine. We therefore consider L15N-proline to be a better tracer than L(1-13C)-leucine for studying protein metabolism in the skin.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 15
    ISSN: 1438-2199
    Keywords: Amino acids ; Taurine ; Kainic acid ; Epilepsy ; Anticonvulsants ; Neuroprotection ; Excitatory amino acids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Male Sprague-Dawley rats received TAU supplementation (1.5% in drinking water) or TAU deficient diets for 4 weeks to test for a possible neuroprotective role of TAU in KA-induced (10 mg/kg s.c.) seizures. TAU supplementation significantly increased serum and hippocampal TAU levels, but not TAU content in temporal cortex or striatum. TAU deficient diets did not attenuate serum or tissue TAU levels. Dietary TAU supplementation failed to decrease the number or latency of partial or clonic-tonic seizures or wet dog shakes, whereas a TAU deficient diet decreased the number of clonictonic and partial seizures. This study does not support previous observations of an anticonvulsant effect of TAU against KA-induced seizures. KAtreatment decreasedα 2-adrenergic receptor binding sites and TAU content in the temporal cortex across all dietary treatment groups, supporting previous evidence of severe KA-induced damage and neuronal loss in this brain region.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 16 (1999), S. 191-213 
    ISSN: 1438-2199
    Keywords: Amino acids ; Enzymatic resolution ; Ester hydrolysis ; Proteases ; Lipases
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The present review outlines recent examples of enzyme-based resolution procedures for amino acids via the hydrolysis of their esters. The resolutions have been achieved by using proteases (α-chymotrypsin, subtilisin and other microbial proteases, and sulfhydryl proteases of plant origin) and lipases. Relevant work utilizing yeast and other microbial cells is also included.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 17
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 16 (1999), S. 251-272 
    ISSN: 1438-2199
    Keywords: Amino acids ; Unusual amino acids ; Aspartic acidβ-semialdehyde ; Aspartaldehyde ; 2-Amino-4-oxobutyric acid ; Enantioselective synthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Strategies for the synthesis of optically active aspartaldehyde derivatives are reviewed. Most of them are using the chiral pool: allylglycine or naturally occurring homoserine, aspartic acid or methionme and side chain modifications. This will be developed in the first part. Some other original routes are also displayed in the second part. Different aspects of each strategy are discussed: the nature and number of steps, the problem of protecting groups, the price and availability of starting materials. Some synthetic applications of such interesting chiral synthons are shown in the last part.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 18
    ISSN: 1438-2199
    Keywords: Amino acids ; Dipeptide derivatives ; Non-proternogenic optically active dipeptide esters ; Dehydrodipeptides ; Chiral rhodium catalysts ; Asymmetric hydrogenation ; Diastereoselectivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary N-[(Z)-N-Benzoyl- orN-Boc-(2-fluorophenyl)dehydroalanyl]-(R)-or (S)-phenylalanine esters were synthesized and hydrogenated to give the corresponding dipeptide derivatives with optical yields in the range of 53–87%de using the cationic rhodium complexes of PROPRAPHOS and BPPM. The efficiency of chiral diphosphine ligands as well the effect of the chiral center in the substrate on the catalytic asymmetric induction was studied.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 19
    ISSN: 1438-2199
    Keywords: Amino acids ; Phytotoxin AS-I analogues ; FAB ; PD ; ESI mass spectrometry ; 1H,13C and 2D NMR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A series of six tetrapeptides, analogues of AS-I phytotoxin, pathogenic to sunflower, have been synthesized either in solution and/or by solid phase methods and have been tested for phytotoxic activity in various plants and cytotoxic activity in three cancer cell lines. These peptides were identified as model compounds by fast atom bombardment (FAB), plasma desorption (PD), electrospray ionization (ESI) mass spectrometry and by1H,1H-1H,13C and1H-13C NMR. The data presented show that in protected tetrapeptides the molecular ion was easily identified whereas some difficulties appeared with the fully deprotected peptides. NMR spectra are given.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 20
    ISSN: 1438-2199
    Keywords: Amino acids ; Diclofenac ; Anti-phlogistics ; Non-proteinogenic amino acids ; Voltaren®. Thionation ; Cyclo-oxygenase inhibitors ; Ulcerogenic gastritis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In search for more potent, particularly less ulcerogenic gastritis that hopefully replace the universal NSAID “Diclofenac”, (2-[(2,6-di-chlorophenyl)amino]-phenylacetic acid, C.A.S. 15307-86-5), twelve new non-proteinogenic amino acid conjugates of the drug, namely that of sarcosine,β-alanine, D-leucine and D-phenylalanine, were synthesized and biologically screened for their anti-inflammatory, analgesic and ulcerogenic activity in rats. “Diclofenac” amino acid esters (IIa-d), were synthesizedvia the corresponding HOSu or HOBt active esters. Alkaline hydrolysis (NaOH) followed by acidification (KHSO4) or thioamide formation (Lawsson's Reagent, C.A.S. 19172-47-5), afforded the corresponding free acids IIIa-d or the thioamides IVa-d respectively. Interestingly, in contrary to the parent “Diclofenac”, the synthesized candidates (except IIId), were entirly nonulcerogenic in rats. Further, they considerably retained a generelized anti-phlogistic activity. The major “Diclofenac” irritating gastric side effect was thus eliminated. Particularly, the sarcosine conjugate IIa and its thiomimic IVa exhibit promising therapeutic perspectives.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 21
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 17 (1999), S. 139-148 
    ISSN: 1438-2199
    Keywords: Amino acids ; Polyamine oxidase ; Polyamines ; Gender ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Variations in level of polyamines and their related enzymes are frequently observed in response to some treatments which affect in a different way male and female. The possibility of a gender-related difference in the oxidation of polyamines was investigated in rats by measuring the activity of polyamine oxidase, a ubiquitous enzyme of vertebrate tissues, which transforms spermine into spermidine and spermidine into putrescine. The study was carried out on thymus, spleen, kidney and liver of young rats of both sexes, and female rats showed a lower polyamine oxidase activity than male rats in all the tissues. We also found higher values of spermidine acetylation in female than male rats in thymus and liver. Owing to these gender-related differences, a higher spermidine N-acetyltransferase/ polyamine oxidase ratio was found in female than in male rats. A second gender-related difference was a higher spermidine/spermine ratio in female than in male, the only exception being the thymus. These basal differences possibly account for the gender-related differences of polyamine metabolic enzyme activities in response to some treatments, including drugs or hormones.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 22
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 17 (1999), S. 195-205 
    ISSN: 1438-2199
    Keywords: Amino acids ; Apis mellifera ; Drones ; Osmolarity ; Age dependency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In the haemolymph of honeybee drones, concentrations of free amino acids were higher than in worker haemolymph, with different relative proportions of individual amino acids. The overall concentration of free amino acids reached its highest level at the 5th day after adult drone emergence, and after the 9th day only minor changes in the concentration and distribution of free amino acids were observed. This coincides with the age when drones reach sexual maturity and change their feeding behaviour. Levels of essential free amino acids were high during the first 3 days of life and thereafter decreased. Osmolarity was lowest at emergence (334 ± 41 mOsm), increased until the age of 3 days (423 ± 32mOsm) and then stayed generally constant until the 16th day of life. Only 25-day-old drones had significantly higher osmolarity (532 ± 38 mOsm). The overall change in osmolarity during a drone's lifetime was about 40%.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 23
    ISSN: 1438-2199
    Keywords: Amino acids ; Conformational constraint ; Cyclic disulfides ; -Cys-Cys-peptides ; Dipeptide mimetics ; Dithiols ; Glutathione analogues
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The glutathione analogue γ-(H-Glu-OH)- -OH (5), containing the 8-membered disulfide ring- replacing the native -Cys-Gly fragment, has been synthesized and characterized together with its reduced dithiol form γ-(H-Glu-OH)-Cys-Cys-OH (6).
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 24
    ISSN: 1438-2199
    Keywords: Amino acids ; Polyamine catabolism ; Polyamine oxidase ; Diamine oxidase ; Testosterone ; Mouse kidney
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In the present study developmental patterns of renal polyamineoxidizing enzymes polyamine oxidase (PAO) and diamine oxidase (DAO) in male and female ICR mice were demonstrated. The effects of testosterone (10μg/100g body weight) on renal PAO and DAO activities were also studied. The differences between sexes in both PAO and DAO activities were most clearly expressed in the immature kidney. At the age of 20 days PAO and DAO activities were 1.52 fold (p 〈 0.01) and 1.75 (p 〈 0.02) respectively higher in male mouse kidney than in female. Maturational processes reflected in significant increases in polyamine- oxidizing enzyme activities mainly in female mouse kidney, comparable with the gain in the kidney wet weight. Our data show that testosterone is able to influence renal PAO and DAO activities in addition to the well-known stimulation of polyamine biosynthesis. The hormonal effects were sex and age dependent. The influence of testosterone on renal PAO activity was mainly age dependent. The slight stimulation of renal PAO activity observed in 20- and 50-day old mice, 24h after testosterone administration, change with a decrease in the enzyme activity at the age of 70 days. The effects of testosterone on renal DAO activity were mainly sex dependent. Testosterone caused stimulation of DAO activity with a very close magnitude (nearly twice) in female mouse kidney, independently of the age of mice. In contrast, in male mice the hormone treatment resulted in a statistically significant increase in renal DAO activity at the age of 70 days (.1.3 fold, p 〈 0.05) only. It could be suggested that our data indicate the different contribution of renal PAO and DAO in androgen regulation of polyamine levels, depending on sex and the stage of the postnatal development.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 25
    ISSN: 1438-2199
    Keywords: Amino acids ; Allohydroxyproline ; Allothreonine ; Chiral separation ; Chirasil-Val ; Hydroxyproline ; Threonine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Experimental conditions for the derivatization and resolution by GLC of all stereoisomers of threonine and 4-hydroxyproline are reported. Threonine was in two steps converted toN,O-bisisobutoxycarbonyl 2,2,2-trifluoroethyl ester derivatives, the second of which was performed under anhydrous conditions. As such the enantiomers could pairwise be separated by capillary gas chromatography on a Chirasil-Val column. SinceL- andD-threonine eluted much earlier than the corresponding allo forms, quantitative determination of the allothreonine content inD- orL-threonine down to the one percent level could be simply accomplished but also enantiomeric impurities could be determined. Unlike for threonine, the corresponding 4-hydroxyproline isomers could not all be resolved asN,O-bisisobutoxycarbonyl 2,2,2-trifluoroethyl esters on this column. Although diastereomers could still be separated, the allo pair cochromatographed and the resolution for theL- andD-isomers was low. Complete separation of the 4-hydroxyproline isomers could be accomplished asN,O-bisprotected isobutyl amides, the formation of which required three derivatization steps. These were used for the determination of allohydroxyproline.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 26
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 17 (1999), S. 323-334 
    ISSN: 1438-2199
    Keywords: Amino acids ; Taurine release ; Cerebellar granule cells ; Celldamaging conditions ; Glutamate receptors ; Veratridine ; Potassium stimulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The release of taurine from cultured cerebellar granule neurons was studied in different cell-damaging conditions, including hypoxia, hypoglycemia, ischemia, oxidative stress and in the presence of free radicals. The effects of both ionotropic and metabotropic glutamate receptor agonists on the release were likewise investigated. The release of [3H]taurine from the glutamatergic granule cells was increased by K+ (50mM) and veratridine (0.1 mM), the effect of veratridine being the greater. Hypoxia and ischemia produced an initial increase in release compared to normoxia but resulted in a diminished response to K. Hypoglycemia, oxidative stress and free radicals enhanced taurine release, and subsequent K− treatment exhibited a correspondingly greater stimulation. A common feature of taurine release in all the bove conditions was a slow response to the stimulus evoked by K+ and particularly to that evoked by veratridine. All ionotropic glutamate receptor agonists potentiated taurine release, but only the action of kainate seemed to be receptor-mediated. Metabotropic receptor agonists of group I slightly stimulated the release. The prolonged taurine release seen in both normoxia and cell-damaging conditions may be of importance in maintaining homeostasis in the cerebellum and reducing excitability for a longer period than other neuroprotective mechanisms.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 27
    ISSN: 1438-2199
    Keywords: Amino acids ; Taurine ; Osmoregulation ; Rat ; Osmolarity sensor protein ENVZ
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Although the involvement of taurine in osmoregulation is well-documented and widely accepted, no detailed mechanism for this function has been reported so far. We used subtractive hybridization to study mRNA steady state levels of genes up- or downregulated by taurine. Rats were fed taurine 100mg/kg body weight per day for a period of three days and hearts (total ventricular tissue) of experimental animals and controls were pooled and used for mRNA extraction. mRNAs from two groups were used for subtractive hybridization. Clones of the subtractive library were sequenced and the obtained sequences were identified by gen bank assignment. Two clones were found to contain sequences which could be assigned to the osmolarity sensor protein envZ, showing homologies of 61 and 65%. EnvZ is an inner membrane protein in bacteria, important for osmosensing and required for porine gene regulation. It undergoes autophosphorylation and subsequently phosphorylates OmpR, which in turn binds to the porin (outer membrane protein) promoters to regulate the expression of OmpF and OmpC, major outer membrane porines. This is the first report of an osmosensing mechanism in the mammalian system, which was described in bacteria only. Furthermore, we are assigning a tentative role for taurine in the osmoregulatory process by modifying the expression of the osmoregulatory sensor protein ENVZ.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 28
    ISSN: 1438-2199
    Keywords: Amino acids ; Protein ; arginine methyltransferase ; Inhibitors ; Ginseng extract ; Arginine derivatives ; Basic amino acids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Protein-arginine N-methyltransferase (protein methylase I) catalyzes methylation of arginyl residues on substrate protein posttranslationally utilizing S-adenosyl-L-methionine as the methyl donor and yields NG-methylarginine residues. Arginyl-fructose and arginyl-fructosyl-glucose from Korean red ginseng were found to inhibit protein methylase I activity in vitro. This inhibitory activity was shown to be due to arginyl moiety in the molecules, rather than that of carbohydrates. Several basic amino acids as well as polyamines were also found to inhibit protein methylase I activity. Interestingly, the intensity of the inhibitory activity was correlated with the number of amino-group in polyamines, thus, in the order of spermine 〉 spermidine 〉 putrescine 〉 agmatine-sulfate, with IC50 at approximately 15 mM, 25 mM, 35 mM, and 50 mM, respectively. On the other hand, neutral amino acids or NaCI did not inhibit the enzyme activity. Lineweaver-Burk plot analysis of the protein methylase I activity in the presence of arginine and spermidine indicated that the inhibition was competitive in nature in respect to protein substrate, with the Ki values of 24.8 mM and 11.5 mM, respectively.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 29
    ISSN: 1438-2199
    Keywords: Amino acids ; Hexafluoroacetone ; α-N-Methylamino acids ; α-N-Phosphinoylmethylamino acids ; Pro-Glu-chimeras ; Pro-Tauchimeras
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A new method for the preparation of N-methylamino acids and some of their derivatives starting from hexafluoroacetone protected amino acids is described. The new concept results in saving of steps compared to conventional protection/activation techniques. Protection and deprotection proceed without racemization.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 30
    ISSN: 1438-2199
    Keywords: Amino acids ; Perfluorinated compounds ; Surfactants ; Complexing properties ; Carnosine ; β ; Amino acids ; Blood substitutes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The reaction of amines or sodium azide with 3-perfluoroalkyl-3-fluoroprop-2-enoate, followed by hydrogenation, affords perfluoroalkylatedβ-alanine analogues in very good yields. These compounds can be linked via an amide bond to produce peptide analogues such as carnosine or carcinine derivatives, which could have surfactive and complexing properties.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 31
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 16 (1999), S. 415-423 
    ISSN: 1438-2199
    Keywords: Amino acids ; SOD-like activity ; Cu (III)-Poly-L-lysine ; Cu(III)-Poly-L-glutamic acid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The SOD-like activity of Cu(III) -complexes with polypeptides poly-L-lysine and poly-L-glutamic acid respectively was investigated. The Cu(II)-polypeptide complexes were first oxidized by K2IrCl6 to give the corresponding Cu(III) -compounds. The oxidation of Cu(II) and the corresponding Cu(II)/Cu(III) potential was evaluated by cyclic voltammetry (c.v.), UV-Vis and EPR spectroscopic (r.t.) experiments. Spin trapping EPR spectra were also conducted to confirm the formation of the superoxide radical. The SOD-like activity of each Cu(III)-complex was proved using the nitro blue tetrazolium (NBT) method slightly modified.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 32
    ISSN: 1438-2199
    Keywords: Amino acids ; Lysine ; Herbicides ; Azotobacter ; Xenobiotics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Production of lysine byAzotobacter chroococcum strain H23 was studied in chemically-defined media amended with different concentrations of alachlor, metolachlor, 2,4-D, 2,4,5-T and 2,3,6-TBA. The presence of 5, 10, and 50μg/ml of alachlor or 2,3,6-TBA significantly decreased quantitative production of lysine. However, the presence 2,4-D or 2,4,5-T at concentrations of 10 and 50μg/ml enhanced the production of lysine. Quantitative production of lysine was not affected as consequence of the addition of metolachlor to the culture medium, showing that the release lysine to the culture media byA. chroococcum was not affected by that herbicide.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 33
    ISSN: 1438-2199
    Keywords: Amino acids ; Trypanothione ; Glutathione ; Benzyloxycarbonyl-reductase ; Hydrocinnamoyl
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Kinetic data for alternative substrates of recombinant trypanothione reductase fromTrypanosoma cruzi were measured for a series ofN-substituted-L-cysteinylglycyl-3-dimethylaminopropylamides, in which the cysteineN-substituent was either a variant of the benzyloxycarbonyl group or was L-phenylalanine or L-tryptophan. Replacing the benzylic ether oxygen atom by CH2. or NH had relatively minor effects on kcat, but raised the value of Km, 4.5- and 10-fold, respectively. Similarly, relative to the carbobenzoxy group, anN-L-phenylalanyl orN-L-tryptophanyl replacement on the cysteine hardly altered kcat, but increased Km, values by 16.6 and 7.4 fold, respectively. These observations were consistent with the Km, values referring primarily to binding for this series of nonspecific substrates.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 34
    ISSN: 1438-2199
    Keywords: Amino acids ; Serotonin receptor ; Serotonin-3 receptor ; Ion channel ; Ion permeability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Human 5-HT3 receptors expressed in HEK 293 cells were studied using patch-clamp techniques. The permeability ratios of cations to Na+ were Li+, 1.16; K+, 1.04; Rb+, 1.11; Cs+ 1.11; NMDG+, 0.04; Ca2+, 0.49, and Mg2+, 0.37. The permeability sequence of the alkali metal cations was Li+ 〉 Rb+ = Cs+ 〉 K+ 〉 Na+. Increased external concentrations of Ca2+ or Mg2+ decreased 5-HT-induced currents at all potentials tested in a voltage-independent manner. The single-channel conductance of human 5-HT3 receptors measured by fluctuation analysis of whole-cell currents was 790 ± 100fS. Differences in the basic properties of 5-HT3 receptors between species may explain interspecies differences in pharmacological properties.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 35
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 17 (1999), S. 301-313 
    ISSN: 1438-2199
    Keywords: Amino acids ; Taurine ; Transporter ; Rat ; Brain ; Heart
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In pro- and eucaryotic life, cellular and subcellular compartments are separated by membranes and the regulated and selective passage of specific molecules across these membranes is a basic and highly conserved principle. We were interested whether taurine, a naturally occuring amino acid, would be able to induce or suppress expression of transporters with the Rationale that taurine was shown to detoxify a series of endogenous toxins and xenobiotics of various chemically non-related structures. For this purpose we used a gene hunting technique, subtractive hybridization, subtracting mRNAs of taurine-treated rat brain and heart from untreated controls. Subtracted mRNAs were then converted to cDNAs, amplified, sequenced and identified by gene bank data. We found five transporter transcripts, the phosphonate transport ATPase PHNC, multidrug transporter homolog MTH104, protein-exportmembrane protein SECD, oligopeptide transporters oppA and oppD, in the brain and two: ABC-transporter BRAF-2 and cation-transport ATPase PACS, in the heart. Homologies of the sequences found were in any case 〉50% thus permitting the identification of transporters with high probability. The biological meaning could be that a naturally occuring amino acid, taurine, modulates complex transport systems. The most prominent finding is the upregulation of a multidrug transporter transcript, explaining a mechanism for the nonselective detoxifying action of taurine.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 36
    ISSN: 1438-2199
    Keywords: Amino acids ; Tyrosine ; Phenylalanine ; Aromatic compounds ; Rumen microorganisms[/klw]
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Rumen contents from three fistulated Japanese native goats fed Lucerne hay cubes (Medicago sativa) and concentrate mixture were collected to prepare the suspensions of mixed rumen bacteria (B), mixed protozoa (P) and a combination of the two (BP). Microbial suspensions were anaerobically incubated at 39°C for 12h with or without 1 MM ofl-phenylalanine (Phe). Phe, tyrosine (Tyr) and other related compounds in both supernatant and microbial hydrolysates of the incubations were analyzed by HPLC. Tyr can be produced from Phe not only by rumen bacteria but also by rumen protozoa. The production of Tyr during 12h incubation in B (183.6 μmol/g MN) was 4.3 times higher than that in P. One of the intermediate products between Phe and Tyr seems to bep-hydroxyphenylacetic acid. The rate of the net degradation of Phe incubation in B (76.O μmol/g MN/h) was 2.4 times higher than in P. In the case of all rumen microorganisms, degraded Phe was mainly (〉53%) converted into phenylacetic acid. The production of benzoic acid was higher in P than in B suspensions. Small amount of phenylpyruvic acid was produced from Phe by both rumen bacteria and protozoa, but phenylpropionic acid and phenyllactic acid were produced only by rumen bacteria.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 37
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 17 (1999), S. 357-368 
    ISSN: 1438-2199
    Keywords: Amino acids ; o-Carboranylalanine ; Histidine ; Bacteria ; Fungi ; Oomycota ; Plasmopara
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Functionalized polyhedral carboranes, including amino acid analogs, have unique physicochemical properties and are used as experimental anticancer agents. However, our current knowledge on their effect in nonmammalian biological systems is limited. We investigated the activity spectrumin vitro ofo-carboranylalanine (o-Cba), considered to be a highly lipophilic analog of phenylalanine, against representative plant pathogenic bacteria and fungi of various taxonomic position. The antibacterial effect ofo-Cba against some species was comparable to that of the widely used agricultural antibiotic, streptomycin. The sensitivity of individual bacterial species too-Cba within the same genus varied to a greater extent than the average sensitivity of various genera. In general, this carborane-containing amino acid was more toxic to Gram positive bacteria (Bacillus, Corynebacterium, Curtobacterium, Micrococcus, Rhodococcus, and Staphylococcus) than to Gram negative ones (Agrobacterium, Erwinia, Escherichia, Pseudomonas, Rhizobium, and Xanthomonas). Compared to the commercial fungicide, prochloraz,o-Cba was weakly toxic against various fungi (Zygo- and Ascomycota). It was also inferior to the commercial fungicide metalaxyl in inhibiting the vegetative growth of oomyceteous plant pathogens (Pythium irregulare, Phytophthora cryptogea and Plasmopara halstedii). Against the asexual spores of P. halstedii,o-Cba, however, was over a thousandfold more active than tridemorph, a selective zoospore inhibitor fungicide. For all taxonomic groups, the observed antimicrobial effect ofo-Cba could be diminished with histidine, but not with phenylalanine. In studies on healthy and mildew-infected sunflower and tobacco plantso-Cba showed neither fungicidal nor phytotoxic effects at 500ppm. This is the first report on the biological activity spectrum of a carborane-containing amino acid.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 38
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 17 (1999), S. 401-413 
    ISSN: 1438-2199
    Keywords: Amino acids ; Indolylacrylic acid ; Tryptophan ; Indolylacryloylglycine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In addition to the main catabolic routes of tryptophan (Trp), there exist minor and less thoroughly investigated pathways; one of these leads to indolylacrylic acid (IAcrA). IAcrA is a plant growth hormone, whereas its biological role in animals is still obscure, as is the way and site where it is formed in the organism. A two-stage production is likely: Intestinal microorganisms catabolize Trp to indole derivatives which are then absorbed and converted to IAcrA and its glycine conjugate, indolylacryloylglyeine (IAcrGly). Our finding of IAcrGly in the urine of proven germ-free piglets points to the possibility that Trp can be converted to IAcrA without the intervention of intestinal microorganisms. Seasonal and age variations, influence of light and connection with photodermatoses have been reported. Besides other pathological conditions the differences in IAcrGly excretion relative to normal controls were especially pronounced in some myopathies, namely in boys with Duchenne muscular dystrophy.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 39
    ISSN: 1569-8041
    Keywords: breast cancer ; fibroblast growth factor ; microvasculature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: Angiogenesis, the process whereby endothelial cells divide and migrate to form new blood capillaries, has been assessed in tumours by measuring microvessel density. High microvessel density is a significant adverse prognostic factor in breast cancer. The angiogenic factor, basic fibroblast growth factor (bFGF), has been associated with tumourigenesis and metastasis in several human cancers. There are few quantitative studies of bFGF expression in normal tissues compared to cancer. Patients and methods: We have measured bFGF levels in 149 human primary breast carcinomas and assessed the findings in relation to microvessel density, oestrogen receptor (ER) and epidermal growth factor receptor (EGFR). Basic FGF levels were measured by ELISA. Western blotting and immunohistochemistry were carreid out to confirm the presence of bFGF. Results: Levels of bFGF were more than 10-fold higher in tumour cytosols compared to reduction mammoplasty tissue and 3-fold compared to non neoplastic cytosols from the same breast as the tumour (P 〈 0.0001). Immunohistochemistry showed bFGF protein was localised exclusively in the stroma whereas no bFGF staining was observed in the epithelial cells. High bFGF levels were significantly related to high ER (P = 0.01). Similarly, high bFGF levels were significantly related to low grade (P = 0.046) and to small tumour size (P = 0.04). No significant relationship was observed between bFGF and microvessel count, EGFR or age. In univariate analysis and in a Cox proportional hazard model bFGF did not reach significance for overall or relapse free survival. Conclusions: Our results show that although bFGF is elevated in breast carcinomas compared to normal breast tissue it is not related to microvessel density and it is not an independent predictor of survival in breast cancer patients. Basic FGF may be one of multiple factors that synergise with other growth factors such as VEGF to enhance angiogenesis.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 40
    ISSN: 1569-8041
    Keywords: breast cancer ; high-dose chemotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 41
    Electronic Resource
    Electronic Resource
    Springer
    Annals of oncology 10 (1999), S. 1163-1170 
    ISSN: 1569-8041
    Keywords: BRCA1 ; BRCA2 ; breast cancer ; family history ; survival
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: Family history is a well recognized risk factor for breast cancer, but its impact in terms of breast cancer survival is uncertain. The recent identification of breast cancer predisposing genes has provided new clinical insights in this field. Design: English literature identified through Medline between 1976 and February 1999 was reviewed including search terms: breast cancer, survival, prognosis, family history, genetics, BRCA1, BRCA2, and related articles. Results: Publications were divided into three categories.Family history-based studies: eighteen articles were reviewed. Four studies showed a statistically significant better survival in patients with a family history of breast cancer, and two studies demonstrated a significantly worse prognosis in this context. The remaining articles showed no significant difference. Linkage studies: Two studies based on linkage to BRCA1 found that overall survival was better in linked families. A third one concluded to a worse outcome in BRCA2-linked tumors. Mutation-based studies: 10 studies looking at the association between germ-line mutations in BRCA1/BRCA2 and clinical outcomes were reviewed. Eight articles reported no significant difference in outcome, whereas two studies showed a worse outcome in patients with mutations. Conclusions: Conflicting data exist as to whether the prognosis of familial or hereditary breast cancer differs from that of sporadic cases. Some of the discrepancies may be explained by methodological differences or biases. However, no studies showed a survival advantage for BRCA1mutation carriers. This seems to indicate that BRCA1-related breast cancer is not associated with a survival advantage, and that in fact, certain BRCA1 germline mutations confer a worse prognosis. However, to adequately answer this question, more efficient molecular tools to identify all the genetic changes responsible for breast cancer predisposition, and large cohort studies to evaluate their clinical consequences, are needed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 42
    ISSN: 1569-8041
    Keywords: breast cancer ; chemotherapy ; margins ; radiotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: Inadequate surgical excision with residual involvement of resection margins by tumour after breast conservation results in increased local recurrence rates. To reduce this risk positive margins are, therefore, usually excised. Systemic treatment with tamoxifen or chemotherapy reduces local recurrence, along with radiotherapy. However, no studies to date have examined the correlation between chemoendocrine treatment, together with radiotherapy, and local relapse in patients with unexcised involved resection margins, having had breast conservation treatment. Patients and methods: The histopathology reports were reviewed of 184 patients who were treated from June 1991 to August 1995 within our randomised study of neoadjuvant versus adjuvant chemoendocrine therapy with mitozantrone and methotrexate (2M) ± mitomycin-C (3M) and tamoxifen, used concurrently with radiation following conservation surgical treatment. Histological resection margin was considered positive if ductal carcinoma in situ (DCIS) or invasive carcinoma was present microscopically less than 1mm from the excision margin. Results: Although 38% of patients had unexcised microscopically involved margins, local relapse rate as first site of relapse was only 1.9% after a median follow up of 57 months. There was no difference in distant relapse (P = 0.2) and survival (P = 0.5) between the positive and negative margins groups. Conclusions: The presence of positive unexcised margins does not have a significant effect on outcome in patients who are treated with chemoendocrine therapy together with radiotherapy. Further clinical trials are required.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 43
    ISSN: 1569-8041
    Keywords: breast cancer ; docetaxel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: Given as first- or second-line chemotherapy, docetaxel appears to have great potential in advanced breast cancer. Patients and methods: Three hundred and seventy-seven locally advanced or metastatic breast cancer patients received docetaxel (Taxotere®) as part of a named patient programme under the care of 108 oncologists from 61 cancer units across the UK. The recommended starting dose was 100 mg/m2, but patients at higher risk of toxicity started at 75 mg/m2. All patients received corticosteroid premedication. The modal number of prior chemotherapy regimens was 2 (range 1–7), 342 patients (91%) had at least one prior anthracycline-based regimen. Results: Response was graded according to the managing clinician's best judgement without formal criteria. The overall response rate (ORR) was 46% among the 331 evaluable patients, 46% among the 299 patients who were 'anthracycline resistant' and 35% among the 82 patients who were 'anthracycline refractory' (progressive disease being the best response obtained to the most recent anthracycline containing regimen). One hundred and ninety-three patients started at the full dose of 100 mg/m2 with an ORR of 55% and 129 started at 75 mg/m2 with an ORR of 33%. In October 1997, some two years after the programme had started, 26 of 377 patients were still alive, although no complete remissions have lasted to this date. Kaplan–Meier survival analysis yielded a median survival of 194 days (95% CI: 178–218 days). Haematological parameters were checked before each course of docetaxel and additionally as clinically indicated. The safety data confirmed that docetaxel has a manageable, predictable side effect profile; 29 of 377 (7.7%) patients were hospitalised as a result of neutropenic sepsis. Conclusions: The results of this named patient programme over a two year timespan confirm that docetaxel is an effective chemotherapy option in patients with locally advanced and/or metastatic breast cancer, including an 'anthracycline refractory' population.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 44
    ISSN: 1569-8041
    Keywords: breast cancer ; dose-intensity ; epirubicin ; G-CS/kwd〉 ; vinorelbine ; weekly schedule
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: This study was designed to explore the effectiveness and tolerability of a weekly regimen of epirubicin and vinorelbine plus granulocyte colony-stimulating factor (G-CSF). Patients and methods: Fifty-two patients with previously untreated advanced breast cancer were treated with epirubicin (25 mg/m2/week) and vinorelbine (25 mg/m2/week) with G-CSF support, for 24 consecutive weeks. Results: The median number of courses per patient was 22 (range 10–24). The administered dose intensity was 23 mg/m2 for both epirubicin and vinorelbine. Ten complete responses (19%) and 30 partial responses (58%) were obtained, for an overall response rate of 77%. None of the patients progressed during treatment. The median response duration and time to progression were both 10 months. A total of 1065 courses were assessed for toxicity. Grade 3 neutropenia was the most common toxic manifestation, (39% of patients), without febrile neutropenia or neutropenic sepsis. Two patients had grade 3 cardiac toxicity, which regressed without sequelae. Median survival was 31 months, with a median follow-up of 24 months (range 9–40). Conclusions: Owing to its effectiveness and tolerability, the weekly regimen of epirubicin and vinorelbine plus G-CSF may represent an acceptable alternative for patients with untreated metastatic breast cancer. It could be tested in the adjuvant and neoadjuvant setting.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 45
    ISSN: 1569-8041
    Keywords: breast cancer ; doxorubicin ; paclitaxel-anthracycline combination ; schedule
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose: We and others have demonstrated the antineoplastic efficacy of paclitaxel as a single agent in metastatic breast cancer. We performed this phase I trial to evaluate the combination of paclitaxel with doxorubicin. Patients and methods: Eligible patients had measurable or evaluable metastatic breast cancer for which this was the initial cytotoxic treatment. They may have received adjuvant chemotherapy with other drugs. The study had four parts. In part 1, the patients received paclitaxel by 24-hour infusion followed by doxorubicin by 48-hour infusion. The paclitaxel dose was to be escalated from a starting dose of 125 mg/m2, and the doxorubicin dose was to remain constant at 60 mg/m2 with treatment repeated every three weeks. The results of part 1 prompted part 2 which was a study of the reverse sequence. Part 3 was a formal study of pharmacology and has been reported (J Clin Oncol 14: 2713–21, 1996). In part 4, patients received doxorubicin 50 mg/m2 by bolus followed by paclitaxel 150 mg/m2 by 24-hour infusion for courses 1 and 2. In all subsequent courses doxorubicin was administered by 48-hour infusion. All patients in all four parts of the study had baseline cardiac scans. All patients received standard premedication for paclitaxel. Results: Forty-eight patients were treated in all four parts of the study. In part 1 (10 patients), the maximum tolerated dose (MTD) was paclitaxel 125 mg/m2/24 hours followed by doxorubicin 48 mg/m2/48 hours as defined by dose-limiting mucositis and neutropenic fever which occurred at the starting dose. For part 2 (21 patients), the MTD was doxorubicin 60 mg/m2/48 hours followed by paclitaxel 160 mg/m2/24 hours. In part 4 (seven patients), the MTD was doxorubicin 50 mg/m2/bolus followed by paclitaxel 135 mg/m2/24 hours. In parts 2 and 4, the dose-limiting toxic effect was neutropenia. Of the entire cohort of 48 patients, seven (15%) had a complete response (one persists at five years without intervening therapy), 26 (54%) had a partial response for an objective response rate of 69% (95% confidence interval (95% CI): 54%–81%). The median follow-up of all living patients is 38+ months (range 20+ to 62+); the median response duration is seven months (range 2–33.7+); the median overall survival is 20.5 months (range 5–54+). The median time to progression is 9.6 months (range 1–33.7+ months). Two patients developed congestive heart failure, one at 24 months after her final dose of doxorubicin which amounted to a cumulative lifetime total doxorubicin dose of 870 mg/m2, one after a total of 660 mg/m2. In both, cardiac symptoms were controlled with medications. Conclusions: The combination of paclitaxel/24 hours with doxorubicin/48 hours is an effective antineoplastic treatment for metastatic breast cancer. However, the incidence of complete response, the median overall survival, and time to progression were not greater than for standard doxorubicin-based combinations. Additionally, a sequence-dependent interaction between paclitaxel and doxorubicin, given in the schedule described here, was defined. Other strategies and schedules should be evaluated to maximize the antineoplastic efficacy of these two potent agents.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 46
    ISSN: 1569-8041
    Keywords: 5-fluorouracil ; breast cancer ; neoadjuvant ; primary chemotherapy ; vinorelbine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: Biological considerations support the use of primary chemotherapy in operable breast cancer; and despite wide variations of used regimens, clinical studies consistently show a significant tumor response allowing breast conservation in many patients otherwise canditates for mastectomy. We investigated the efficacy and the acceptance of a combination chemotherapy with vinorelbine, 5-fluorouracil and high-dose folinic acid in operable breast cancer with favorable prognostic factors and tested the relationship of hormone receptor status, Ki67, p53, c-erbB2 and bcl-2 with treatment response. Patients and methods: Thirty-nine patients (median age 51 years, range 36–71 years), eight with T1, twenty-eight with T2 and two with T3 lesions, were treated with 5-fluorouracil (350 mg/m2, i.v. on day 1 to 3) preceded by folinic acid (100 mg/m2 i.v. on day 1 to 3) and vinorelbine, given on days 1 and 3 at the dose of 20 mg/m2 (FLN regimen). Therapy was administered on an outpatient basis every three weeks. Non responders had surgery after three courses, while complete or partial responders underwent surgery after six courses. All but one were evaluable for response and toxicity. Results: Objective responses were observed in 23 of the 38 evaluable patients (61%; 95% CI: 46%–76%): three complete responses (8%) and 20 partial responses (53%). Fifteen patients (39%) had stable disease, of whom nine (23%) had minor response. None of the patients had disease progression during treatment. Objective responses were significantly associated with no expression of estrogen and/or progesteron receptors and 〉50% decrease in Ki67 after induction chemotherapy. Tolerance was excellent and none of the patients experienced grade 2 alopecia. Conclusions: The ‘moderate’ efficacy of this regimen might be partially due to the selection of patients with high expression of steroid hormone receptors and low proliferation rate, which have an unfavorable impact on response to this chemotherapy.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 47
    ISSN: 1569-8041
    Keywords: breast cancer ; cardiotoxicity ; cyclophosphamide ; epirubicin ; high dose
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose: To prospectively evaluate the long term cardiac effects of high-dose epirubicin and cyclophosphamide given to women with early stage, poor prognosis breast cancer. Patients and methods: Women with stage 2 breast cancer and 10+ nodes or 4+ nodes and estrogen receptor negative tumor, or stage 3 breast cancer received three cycles of epirubicin 200 mg/m2 and cyclophosphamide 4 gm/m2 with peripheral blood progenitor cell and filgrastim support. Treatment was given every 28 days (n = 79) or 21 days (n = 20). Fifty patients received radiotherapy to the chest wall or breast, 25 of to the left side. Patients were assessed clinically regularly during chemotherapy and at least three times yearly after completion of treatment. Cardiac left ventricular ejection fraction (LVEF) was assessed by radionuclide scan before therapy, after each cycle of chemotherapy, three months and six months after completion of chemotherapy, and yearly thereafter until relapse. Results: Ninety-nine women were treated, and 92 completed all three cycles of chemotherapy. The median age was 43 years (range 24 to 60 years). All patients were included in this analysis. The median relapse-free survival was 39 months (11 to 68 months). There was a significant fall in LVEF during chemotherapy. In general, there was no further deterioration in cardiac function from the third month after cessation of treatment, however there was substantial variation between individuals. 35 patients had at least one LVEF measure less than normal (〈50%), but the LVEF returned to normal in 20 of these with further follow-up. Cardiac dysfunction was not increased in women who received radiotherapy and was not different between cohorts given chemotherapy every three or every four weeks. One patient died of acute myocardial necrosis following the third cycle of chemotherapy. Two patients developed clinical evidence of cardiac failure, and another had radiological signs but was asymptomatic. One woman died of progressive cardiac failure, one recovered clinically but also developed recurrent breast cancer, while the third recovered after commencement of medical therapy. Conclusions: During follow-up after high-dose epirubicin and cyclophosphamide as delivered in this study, the LVEF fell to below normal in approximately one third of patients. However, in over half of these patients the LVEF subsequently recovered to the normal range, and the incidence of clinically evident chronic cardiac failure was low. Further follow-up is required to assess the long- term safety. A randomized comparison with standard-dose anthracycline-based chemotherapy is needed to determine whether this regimen is associated with an increased risk of clinical cardiac toxicity.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 48
    Electronic Resource
    Electronic Resource
    Springer
    Biology and fertility of soils 29 (1999), S. 257-261 
    ISSN: 1432-0789
    Keywords: Key words Alpine nitrogen cycle ; Amino acids ; Kobresia myosuroides ; Organic nitrogen ; Plant-microbe competition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract  Microbes are assumed to possess strong competitive advantages over plants for uptake of nutrients from the soil. The finding that non-mycorrhizal plants can obtain a significant fraction of their N requirement from soil amino acids contradicts this assumption. The amino acid glycine (Gly) has been used as a model amino acid in many recent studies. Our preliminary studies showed that Gly was a poor substrate for microbial growth compared to other amino acids. We tested the hypothesis that the alpine sedge Kobresia myosuroides competes better for Gly than for other amino acids because of decreased microbial demand for this compound. Soil microbial populations that could grow using Gly as a sole carbon source were about 5 times lower than those that could grow on glutamate (Glu). Gly supported a significantly lower population than any of the ten other amino acids tested except serine. In contrast, K. myosuroides took up Gly from hydroponic solution at faster rates than Glu. In plant-soil microcosms, plants competed with soil microbes 3.25 times better for Gly than for Glu. We conclude that the low microbial demand and the rapid plant uptake of Gly relative to other amino acids allow Gly to be an especially important nitrogen source for K. myosuroides.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 49
    Electronic Resource
    Electronic Resource
    Springer
    Zeitschrift für Lebensmittel-Untersuchung und -Forschung 208 (1999), S. 50-56 
    ISSN: 1431-4630
    Keywords: Key words Flavor enhancer ; Savory flavoring ; Taste ; Amino acids ; Partial least squares regression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Enzymatically hydrolyzed vegetable protein was produced from soy protein using hydrolysis times of 0–20 h. The development of sensory properties and the pattern of protein degradation was followed. Around two-thirds of the final amount of free amino acids and degree of hydrolysis (DH) were achieved during the first 4 h of hydrolysis. Between 6 h and 10 h of hydrolysis the bouillon-like tastes increased significantly (P〈0.001). In this time interval the amount of free amino acids exceeded 40% of the total amino acids and the DH exceeded 50% of the theoretically possible (100%). Using partial least squares regression with standardisation of free amino acid data according to their taste threshold values showed that free glutamic acid, aspartic acid and lysine correlated with the bouillon-like tastes. By standardisation of free amino acid data with respect to their SD the specificity of the enzymes for amino acid side-chains could be seen.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 50
    Electronic Resource
    Electronic Resource
    Springer
    Zeitschrift für Lebensmittel-Untersuchung und -Forschung 208 (1999), S. 355-361 
    ISSN: 1431-4630
    Keywords: Key words Flavor enhancer ; Taste ; Amino acids ; Carbohydrates ; Maillard reaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Hydrolyzed vegetable protein produced using hydrochloric acid (HVP) or proteolytic enzymes (EVP) was given a maturation period of up to 6 weeks at 30  °C. The maturation resulted in a darker color for both hydrolysates, but the sensory profiles were not altered to any great extent. For both hydrolysates a decrease in the amount of free amino acids or an increase in the amount of bound amino acids was seen, and for EVP, a decrease in the amount of free monosaccharides was likewise observed. In HVP the mono- and polysaccharides were destroyed during hydrolysis. The changes in amino acids could be due to, for example, a reversible binding to either a monosaccharide in EVP or a degradation product of carbohydrates in HVP, leading to the first stage of the Maillard reaction. These early reactions did not proceed to any flavor-giving Maillard reaction compounds. Maturation can therefore not be used to enhance the flavor of protein hydrolysates under the applied production conditions.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 51
    ISSN: 1432-1106
    Keywords: Key words Gabaculine ; NMR spectroscopy ; Microdialysis ; Amino acids ; Compartmentation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The aim of this work was to study the neurochemical effects in the brain of GABA-transaminase inhibition by systemic administration of gabaculine (100 mg/kg, i.a.) in the rat. In order to investigate neurotransmitter and related amino-acid compartmentation and metabolism, we have developed an original tool: the coupling, in vivo, on the same animal, of 2D COSY 1H-NMR spectroscopy with intracerebral microdialysis. The main result is a continuous increase in GABA levels, both in the intracellular compartment (up to 3000±450%; P〈0.001) and extracellular compartment (up to 808±82%; P〈0.01) at the sixth hour. The intracellular increase in GABA level became significant at the first hour following gabaculine administration, whereas the extracellular level increased as of the second hour, probably indicating that accumulation of GABA in nerve endings precedes its release in synaptic clefts. Moreover, the levels of the excitatory amino acids, glutamate and aspartate, were decreased both in the intra- and extracellular compartments, thus enhancing sedative effects of the drug. We also observed a decrease in the global energetic creatine-phosphocreatine pool, which also could be related to the sedative properties of gabaculine, measurable by the diminution of cortical electrical activity and mean arterial blood pressure. Finally, the coupling between 2D 1H-NMR spectroscopy and intracerebral microdialysis appears to be an original tool for investigating the cerebral metabolic effects induced by pharmacological agents, in situ, in living animals.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 52
    ISSN: 1432-1939
    Keywords: Key words Estuarine food web ; Stable isotopes ; Amino acids ; Growth experiment ; Crustacean metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The stable isotope compositions (C and N) of plants and animals of a marsh dominated by Spartina alterniflora in the Delaware Estuary were determined. The study focused on the juvenile stage of the Atlantic blue crab, Callinectes sapidus, and the importance of marsh-derived diets in supporting growth during this stage. Laboratory growth experiments and field data indicated that early juvenile blue crabs living in the Delaware Bay habitat fed primarily on zooplankton, while marsh-dwelling crabs, which were enriched in 13C relative to bay juveniles, utilized marsh-derived carbon for growth. In laboratory experiments, the degree to which juvenile blue crabs isotopically fractionated dietary nitrogen, as well as the growth rate, depended on the protein quality of the diet. The range of δ13C of amino acids in laboratory-reared crabs and their diets was almost 20‰, similar to the isotopic range of amino acids of other organisms. In laboratory studies, the δ13C of nonessential and essential amino acids in the diet were compared to those in juvenile crabs. Isotopic fractionation at the molecular level depended on diet quality and the crabs' physiological requirements. Comparison of whole-animal isotope data with individual amino acid C isotope measurements of wild juvenile blue crabs from the bay and marsh suggested a different source of total dietary carbon, yet a shared protein component, such as zooplankton.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 53
    ISSN: 1432-0738
    Keywords: Key words 2 ; 3 ; 7 ; 8-Tetrachlorodibenzo-p-dioxin ; TCDD ; Phosphoenolpyruvate carboxykinase ; PEPCK ; Glucose ; Glycogen ; Amino acids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Reduced gluconeogenesis due to decreased activity of key gluconeogenic enzymes in liver, together with feed refusal, has been suggested to play an important role in 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced lethality in rats. This study was carried out to further analyse the toxicological significance of reduced gluconeogenesis by comparing dose-responses and time-courses of effects of TCDD on the activity of phosphoenolpyruvate carboxykinase (PEPCK) in liver, liver glycogen concentration as well as plasma concentrations of glucose and amino acids in both genders of TCDD-sensitive Long-Evans (L-E) rats and TCDD-resistant Han/Wistar (H/W) rats. A dose-dependent decrease in PEPCK activity was observed in H/W rats, but in L-E rats the activity was not decreased. However, TCDD impaired the strong increase in liver PEPCK activity observed in pair-fed controls of the L-E strain. Liver glycogen concentrations were severely decreased in L-E rats and moderately in H/W rats. This effect seems to be secondary to reduced feed intake, since a similar decrease was seen in pair-fed controls. Decreases in plasma glucose concentrations were also more profound in L-E rats than in H/W rats, but pair-fed controls were generally less affected. Circulating concentrations of amino acids were markedly increased in TCDD-treated L-E rats, which is likely to reflect increased mobilization of amino acids and their decreased metabolism in liver. Reduction of liver PEPCK activity cannot account for the sensitivity difference of these two strains of rats in terms of mortality. Nevertheless, the response of both strains of TCDD-treated rats regarding gluconeogenesis is different from that seen in pair-fed controls and suggesting that impairment of this pathway contributes to the development of the wasting syndrome.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 54
    ISSN: 1438-2199
    Keywords: Amino acids ; Cerebellar granule cells ; Neurotoxicity ; Terfenadine ; Excitatory amino acids ; Histamine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Exposure of cultured cerebellar neurons to the histamine H1 receptor antagonist terfenadine resulted in neuronal degeneration and death. Terfenadine neurotoxicity was dependent upon concentration and time of exposure. After 2h exposure, 20µM terfenadine reduced the number of surviving neurons by 75%, and as low as 10nM terfenadine induced significant neurotoxicity after 5 days of exposure. Neuronal sensitivity to terfenadine changed with age in culture, and at 25 days in culture neurons appeared to be much less sensitive than at 5 or 9–17 days in culture. Neurotoxicity by terfenadine could not be prevented by high concentrations of histamine (5 mM), but it was significantly delayed by blocking NMDA or non-NMDA glutamate receptors with MK-801 or CNQX respectively, suggesting the involvement of excitatory transmission mediated by glutamate in the neurotoxicity induced by terfenadine in these neurons. We also found that the presence of terfenadine (5,µM) unveiled the potential excitotoxicity of the non-NMDA receptor agonist AMPA (100µM), and reduced the concentration of glutamate necessary to induce excitotoxicity, compared to untreated cultures. These results suggest a role for terfenadine in the modulation of the excitotoxic response mediated in cerebellar neurons through ionotropic glutamate receptors.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 55
    ISSN: 1438-2199
    Keywords: Amino acids ; eIF-5A ; Hypusine ; Protein folding ; Posttranslational modification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The molecular properties of the human eukaryotic initiation factor 5A precursor and its site directed Lys50 → Arg variant have been investigated and compared. Structure perturbation methods were used to gain information about the protein architecture in solution. Intrinsic and extrinsic spectroscopic probes strategically located in the protein matrix detected the independent unfolding of two molecular regions. Three cystemes out of four were titrated in the native protein and the peculiar presence of a tyrosinate band at neutral pH was detected. At alkaline pH only two tyrosines out of three were titratable in the native protein, with an apparent pK of about 9.9. Native protein and its Lys50 → Arg variant reacted in a similar fashion to guanidine and to pH variation, but differently to thermal stress. The complex thermal unfolding of both proteins indicated the presence of intermediates. Spectroscopic data showed that these intermediates are differently structured. Consequently, the two proteins seem to have different unfolding pathways.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 56
    ISSN: 1438-2199
    Keywords: Amino acids ; 5/6 nephrectomy ; Renal failure ; Amino acid transport ; Kidney ; Triiodothyronine ; Dexamethasone ; Amino acid load ; Rats
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In anaesthetized adult female rats, the renal amino acid handling was measured six days after 5/6 nephrectomy (5/6NX). The distinct rise in blood urea nitrogen as well as the significant reduction in urine flow and GFR indicate an impairment of kidney function. In principle, in 5/6NX rats amino acid plasma concentrations were comparable to those of control animals with two intact kidneys, whereas the fractional excretions (FEAA) of most endogenous amino acids measured were significantly enhanced. After bolus injection of leucine or taurine (each 20 mg/100 g b.wt.) or glutamine (90 mg/ 100 g b.wt.), dissolved in 2m1 normal saline per 100 g b.wt., the FEAA of both the amino acids administered and the endogenous amino acids increased as a sign of overloaded amino acid reabsorption capacity. This effect was more pronounced in 5/6NX rats than in controls. As early as one hour after amino acid load, plasma concentrations and FEAA returned to baseline values of 5/6NX rats. A pretreatment with triiodothyronine (20,µg/100 g b.wt.) or dexamethasone (60 µg/100 g b.wt.), both given intraperitoneally once daily for 3 days, stimulated the renal amino acid transport capacity in 5/6NX rats: the increase in FEAA after amino acid load was significantly lower compared to non-pretreatred animals. This stimulation could be shown for the bolus amino acids and the endogenous amino acids and was more distinct in 5/6NX rats than in controls with two intact kidneys.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 57
    ISSN: 1438-2199
    Keywords: Amino acids ; Nitric oxide ; Ornithine decarboxylase ; Proliferation ; Cell death ; Cardiomyocytes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Nitric oxide (NO) is a molecule involved in several signal transduction pathways leading either to proliferation or to cell death. Induction of ornithine decarboxylase (ODC), the key enzyme of polyamine biosynthesis, represents an early event preceding DNA synthesis. In some cell types increased ODC activity seems to be involved in cytotoxic response. We investigated the role of NO and ODC induction on the events linked to cell proliferation or to cell death in cultured chick embryo cardiomyocytes. Exposure of cardiomyocytes to tumor necrosis factor (TNF) and lipopolysaccharide (LPS) caused NO synthase (NOS) and ODC induction as well as increased incorporation of [3H]-thymidine. This last effect was blocked by a NOS inhibitor and was strongly reduced by difluoromethylornithine (DFMO), an irreversible inhibitor of ODC. Sodium nitroprusside (SNP), an exogenous NO donor, inhibited the increases of NOS and ODC activities and abolished the mitogenic effect of TNF and LPS. Moreover, SNP alone caused cell death in a dose dependent manner. The cytotoxicity of SNP was not affected by DFMO while it was prevented by antioxidants. The results suggest that different pathways would mediate the response of cardiomyocytes to NO: they can lead either to ODC induction and DNA synthesis when NO is formed through NOS induction or to growth inhibition and cell death, when NO is supplied as NO donor. Increased polyamine biosynthesis would mediate the proliferative response of NO, while the cytotoxicity of exogenous NO seems to involve some oxidative reactions and to depend on the balance between NO availability and cellular redox mechanisms.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 58
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 16 (1999), S. 297-320 
    ISSN: 1438-2199
    Keywords: Amino acids ; Pipecolic acid ; Pipecolic acid derivatives ; Asymmetric synthesis ; Hemisyntheses ; Chiral auxiliaries
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Results in the field of asymmetric synthesis of pipecolic acid derivatives are reviewed. Three sections describe the asymmetric syntheses of the title compounds (i) from the chiral pool (α-amino acids or carbohydrates) (ii) using a chiral auxiliary either derived from terpenes,α-amino acids, tartaric acid, an amine orβ-amino alcohols (iii) by means of asymmetric catalysis.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 59
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 16 (1999), S. 321-343 
    ISSN: 1438-2199
    Keywords: Amino acids ; Amino alcohols ; β-Lactams ; NCA ; Peptides ; Synthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The potential ofβ-lactams as intermediates for the access toα- andβ-amino acid-derived peptides is shortly reviewed, with major focus on the technologies developed in our group. The two general strategies lie, on one side, in the oxidative ring expansion of 3-hydroxyβ-lactams toN-carboxyα-amino acid anhydrides or Leuch's anhydrides and subsequent coupling withα-amino acid esters and, on the other side, in the nucleophilic ring opening ofN-Boc-β-lactams. Both approaches have been successfully applied to the synthesis ofα,β-diamino acid,α-amino-β-hydroxy acid, polyhydroxylatedα-amino acid,α,α-disubstitutedα-amino acid,β-amino acid,β-amino-α-hydroxy acid andβ,β-disubstitutedβ-amino acid derived peptides. Because of the mild reaction conditions needed for the above transformations and the highly stereoselective procedures employed for the construction of the startingβ-lactam ring, the whole process allows the production of optically pure final products.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 60
    ISSN: 1438-2199
    Keywords: Amino acids ; Clonidine ; GABAA receptor antagonists ; GABA turnover ; SHR ; WKY rats
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of γ-aminobutyric acid (GABA)A antagonists (bicuculline, picrotoxin) on clonidine hypotension in spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) rats were examined. The GABA turnover changes after clonidine injection in both strains were also studied. Administration of clonidine alone induced the stronger decrease of systolic blood pressure (SBP) in SHR. Co-dosage of clonidine with these agents reduced its hypotensive effect in dose dependent manner and the effectiveness of both antagonists was higher in SHR. We find that clonidine stimulates GABA synthesis in the hypothalamus and the pons-medulla in both strains but the GABA turnover rate is significantly slower in SHR. Therefore, the differences in inhibitory action of GABAA receptor anatgonists between WKY and SHR rats may be explained by central GABAergic system dysfunction in the hypertension. Our results indicate that the down regulation of the GABAergic system observed in hypertension may be compensated by the action of clonidine.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 61
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 17 (1999), S. 185-193 
    ISSN: 1438-2199
    Keywords: Amino acids ; Anaerobic bacteria ; Catabolism ; HPLC ; Stereochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The utilization ofd- andl -amino acids with acidic, basic or polar side chains was demonstrated by HPLC. Two species of the anaerobeFusobacterium utilized D-lysine and the L isomers of glutamate, glutamine, histidine, lysine and serine. OnlyF. varium usedl-arginine,d-glutamate andd-serine as substrates, whereasF. nucleatum specifically utilizedd-histidine andd-glutamine.d-Glutamate accumulated in F. nucleatum cultures supplemented withd-glutamine, and ornithine was detected when eitherdl- orl-arginine was included inF. varium cultures. Based on literature precedents,d-glutamate andd-histidine are isomerized to their L isomers prior to degradation, but separate catabolic pathways are possible for each enantiomer of lysine and serine.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 62
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 17 (1999), S. 227-241 
    ISSN: 1438-2199
    Keywords: Amino acids ; Glutamine ; Lymphocyte ; Macrophage ; Mononuclear cell ; Cytokine ; Infection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Glutamine is utilised at a high rate by cells of the immune system in culture and is required to support optimal lymphocyte proliferation and production of cytokines by lymphocytes and macrophages. Macrophage-mediated phagocytosis is influenced by glutamine availability. Hydrolysable glutamine dipeptides can substitute for glutamine to support in vitro lymphocyte and macrophage functions. In man plasma and skeletal muscle glutamine levels are lowered by sepsis, injury, burns, surgery and endurance exercise and in the overtrained athlete. The lowered plasma glutamine concentrations are most likely the result of demand for glutaminne (by the liver, kidney, gut and immune system) exceeding the supply (from the diet and from muscle). It has been suggested that the lowered plasma glutamine concentration contributes, at least in part, to the immunosuppression which accompanies such situations. Animal studies have shown that inclusion of glutamine in the diet increases survival to a bacterial challenge. Glutamine or its precursors has been provided, usually by the parenteral route, to patients following surgery, radiation treatment or bone marrow transplantation or suffering from injury. In most cases the intention was not to stimulate the immune system but rather to maintain nitrogen balance, muscle mass and/or gut integrity. Nevertheless, the maintenance of plasma glutamine concentrations in such a group of patients very much at risk of immunosuppression has the added benefit of maintaining immune function. Indeed, the provision of glutamine to patients following bone marrow transplantation resulted in a lower level of infection and a shorter stay in hospital than for patients receiving glutamine-free parenteral nutrition.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 63
    Electronic Resource
    Electronic Resource
    Springer
    Amino acids 17 (1999), S. 277-283 
    ISSN: 1438-2199
    Keywords: Amino acids ; D-Aspartic acid ; D-Leucine ; Pineal gland ; Sympathetic nervous system ; Anesthesia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In a previous report (Hamase, K. et al., Biochim Biophys Acta 1134: 214–222 (1997)), we showed that the rat pineal gland contains D-leucine (D-Leu) as well as D-aspartic acid (D-Asp). In this communication we report alterations in the content of these D-amino acids during anesthesia. The D-Asp content was significantly increased from 2.8 to 5.0, 4.8 and 5.8 nmol/pineal gland by administration of ether, urethane and pentobarbital, respectively. In contrast, the D-Leu content was decreased by administration of urethane or pentobarbital. The D-Leu content decreased from 4.2 to 2.2 pmol/pineal gland 4 hours after administration of urethane, although the content remained unchanged until 1.5 hours after administration. The content of the L-enantiomers of these amino acids were not affected by anesthesia. The urethane-induced decrease in D-leucine content was almost completely suppressed by aβ-agonist, (-)-isoproterenol, whereas the agonist itself had no effect.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 64
    ISSN: 1438-2199
    Keywords: Amino acids ; Glycyl-L-proline ; Urine ; Trophicity ; Collagen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Glycyl-L-proline (gly-pro) is an end product of collagen metabolism that is further cleaved by prolidase (EC 3.4.13.9); the resulting proline molecules are recycled into collagen or other proteins. We postulated a relationship between defective gly-pro hydrolysis, increased collagen degradation and skin destruction. This relationship was tested using HPLC to measure the gly-pro in urine. 24 hour urine samples were collected from 27 old people (86 ± 6 years old), of whom 15 were suffering from skin pressure sores of the sacrum or calcaneus. The urine from patients with pressure sores contained significantly more gly-pro than the urine from the control. A cut-off at 7μmol/ mmol creatinine gave the test a positive predictive value of 70%. Collagen breakdown was also increased as indicated by the increase of hydroxyproline (hyp) in the urine. But this breakdown seemed to stop at the gly-pro step.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 65
    ISSN: 1438-2199
    Keywords: Amino acids ; Taurine release ; Metabotropic glutamate receptors ; Hippocampal slices ; Adult ; Developing mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The inhibitory amino acid taurine has been held to function as an osmoregulator and modulator of neural activity, being particularly important in the immature brain. lonotropic glutamate receptor agonists are known markedly to potentiate taurine release. The effects of different metabotropic glutamate receptor (mGluR) agonists and antagonists on the basal and K+-stimulated release of [3H]taurine from hippocampal slices from 3-month-old (adult) and 7-day-old mice were now investigated using a superfusion system. Of group I metabotropic glutamate receptor agonists, quisqualate potentiated basal taurine release in both age groups, more markedly in the immature hippocampus. This action was not antagonized by the specific antagonists of group I but by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and 6-nitro-7-sulphamoylbenzo[f]quinoxaline-2,3-dione (NBQX), which would suggest an involvement of ionotropic glutamate receptors. (S)-3,5-dihydroxyphenylglycine (DHPG) potentiated the basal release by a receptor-mediated mechanism in the immature hippocampus. The group II agonist (2S, 2′R, 3′R)-2-(2′,3′-dicarboxycyclopropyl)glycine (DCG IV) markedly potentiated basal taurine release at both ages. These effects were antagonized by dizocilpine, indicating again the participation of ionotropic receptors. Group III agonists slightly potentiated basal taurine release, as did several antagonists of the three metabotropic receptor groups. Potassium-stimulated (50 mM K+) taurine release was generally significantly reduced by mGluR agents, mainly by group I and II compounds. This may be harmful to neurons in hyperexcitatory states. On the other hand, the potentiation by mGluRs of basal taurine release, particularly in the immature hippocampus, together with the earlier demonstrated pronounced enhancement by activation of ionotropic glutamate receptors, may protect neurons against excitotoxicity.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 66
    Electronic Resource
    Electronic Resource
    Springer
    Annals of oncology 10 (1999), S. 197-203 
    ISSN: 1569-8041
    Keywords: breast cancer ; cost-effectiveness ; mammography ; screening
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: Mammography screening is a promising method for improving prognosis in breast cancer. Patients and methods: In this economic analysis, data from the Norwegian Mammography Project (NMP), the National Health Administration (NMA) and the Norwegian Medical Association (NMA) were employed in a model for cost-effectiveness analysis. According to the annual report of the NMP for 1996, 60,147 women aged 50–69 years had been invited to a two-yearly mammographic screening programme. 46,329 (77%) had been screened and 337 (0.7%) breast cancers had been revealed. The use of breast conserving surgery (BCS) was in this study estimated raised by 17% due to screening, the breast cancer mortality decreased by 30% and the number of life years saved per prevented breast cancer death was calculated 15 years. Results: The cost per woman screened was calculated £75.4, the cost per cancer detected £10,365 and the cost per life year (LY) saved £8,561. A raised frequency of BCS, diagnosis and adjuvant chemotherapy brought two years forward, follow-up costs and costs/savings due to prevented breast cancer deaths were all included in the analysis. A sensitivity analysis documented mammography screening cost-effective in Norway when four to nine years are gained per prevented breast cancer death. Conclusion: Mammography screening in Norway looks cost- effective. Time has come to encourage national screening programmes.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 67
    ISSN: 1569-8041
    Keywords: anastrozole ; aromatase inhibitors ; breast cancer ; hormonal therapy ; letrozole ; review ; vorozole
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Three new aromatase inhibitors have recently completed phase III evaluation as treatment of metastatic breast cancer in post-menopausal women whose disease has progressed despite tamoxifen therapy: anastrozole (ARIMIDEX, Zeneca), letrozole (FEMARA, Novartis) and vorozole (RIVIZOR, Janssen). All belong to the third generation of non-steroidal aromatase inhibitors, and each is superior to previous generations in terms of potency and selectivity. The trials that have been performed compare each agent to megestrol acetate, and letrozole and vorozole to aminoglutethimide. Although the studies are not directly comparable due to differing study designs and patient populations, it has been demonstrated each of these drugs provides single agent, once-daily, oral palliation of hormone-responsive, post-menopausal metastatic breast cancer. Letrozole is clearly more effective than megestrol acetate, and anastrozole and vorozole are possibly so. All three are better tolerated than the progestin, particularly in terms of weight gain. Both letrozole and vorozole are significantly more effective, and better tolerated than aminoglutethimide. Overall, this most recent generation of aromatase inhibitors is a clear improvement on our current standard second-line therapies. In 1999, tamoxifen remains the first choice in the hormonal therapy of breast cancer. Following tamoxifen failure, the optimal second-line hormonal therapy remains undefined, but aminoglutethimide and megestrol acetate are no longer optimal therapy in this setting. The third-generation non-steroidal aromatase inhibitors must now be compared to each other, to the steroidal aromatase inhibitors, to the pure anti-oestrogens, and to tamoxifen.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 68
    ISSN: 1569-8041
    Keywords: breast cancer ; cisplatin ; ovarian cancer ; paclitaxel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Despite the known association of these malignancies, the incidence of a synchronous presentation of breast and ovarian cancer is low, and the current literature does not address an approach to this clinical problem directly. We report a greater than 2.5 year disease-free survival in a patient treated for synchronous stage IIIB inflammatory breast cancer and stage IIIC epithelial ovarian cancer. The prolonged disease-free survival in our case may provide some guidance in this unusual clinical situation.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 69
    ISSN: 1569-8041
    Keywords: breast cancer ; local regional therapy ; stem-cell transplantation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: High-dose chemotherapy with autologous stem-cell transplantation is used increasingly in the treatment of poor-prognosis primary breast cancer. Because these patients may be cured with standard multimodality therapy, it is important to address both the efficacy of transplantation, and its effect on the delivery of standard treatments including local radiation therapy. Patients and methods: Patients with high risk primary breast cancer were treated with high-dose cyclophosphamide and thiotepa and stem-cell transplant following surgery and conventional-dose adjuvant chemotherapy. Outcome, including sites of failure and delivery of local radiation therapy, was assessed for 103 patients. Results: Overall and disease-free survival rates at 18 months were 83% (± 4%) and 77% (± 4%) respectively. Twenty patients (19.4%) received radiation therapy prior to transplant. Of the remaining 83, 77 received radiation therapy after transplant. Overall, 5 (19.2%) of 26 first sites of recurrence were local alone. For patients receiving radiation prior to transplant, 3 of 7 (43%, 95% CI: 6%–80%) sites of first recurrence were local, while 2 of 19 (10.5%, 95% CI: 0%–24.5%) sites of first recurrence were local alone in patients receiving post-transplant radiation or no radiation. Conclusion: Transplantation does not appear to significantly compromise the delivery or outcome of local radiation therapy for primary breast cancer.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 70
    Electronic Resource
    Electronic Resource
    Springer
    Annals of oncology 10 (1999), S. 129-137 
    ISSN: 1569-8041
    Keywords: adjuvant treatment ; breast cancer ; systemic therapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The theoretical prediction that breast cancer is a systemic disease, and that patients may benefit from addition of systemic therapy to local treatment, has now been confirmed by three decades of clinical investigations. A long-term follow up of individual trials and the International Overview based on meta-analyses clearly showed the potential of both hormonal therapies and chemotherapy to prolong disease-free and overall survival in nearly all groups of patients. The benefits have been demonstrated for both premenopausal and postmenopausal patients, with both node-negative and node-positive disease. However, there is still considerable uncertainty regarding the most appropriate treatment for each individual patient. In the present review, the results of meta-analysis are highlighted in the context of the new trials supporting the value of chemoendocrine therapy and anthracycline-based therapy. The results of prospective randomised trials evaluating the role of dose intensification, drug sequencing and dose density are discussed. Also presented are new treatment strategies, such as preoperative chemotherapy and high-dose chemotherapy with stem cell support, the value of which remains to be confirmed. Future possibilities opened by inclusion of biologics into adjuvant therapy are discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 71
    Electronic Resource
    Electronic Resource
    Springer
    Annals of oncology 10 (1999), S. 139-146 
    ISSN: 1569-8041
    Keywords: anthracycline ; breast cancer ; chemotherapy ; HER-2 antibody ; N,N-diethyl-2[4-(phenylmethyl)-phenoxy] ethanamine.HCl (DPPE, BMS-217380-01) ; paclitaxel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Anthracyclines and taxanes are the two most active classes of chemotherapy for the treatment of advanced breast cancer. Recent studies have investigated combination therapy including doxorubicin (Dox) and paclitaxel. The efficacy of this combination has been established in a phase III study conducted by ECOG, comparing Dox/paclitaxel versus Dox versus paclitaxel. The combination is superior to Dox or paclitaxel with respect to response rate and time to disease progression, indicating that the combination provides a new standard for the first line treatment of metastatic breast cancer [1]. Phase II studies using higher doses of Dox and using shorter infusions of paclitaxel have suggested the combination can be further optimised; Gianni reported a 94% objective response rate using Dox 60 mg/m2 followed by paclitaxel 175 mg/m2 given over three hours [2]. The more active regimens are associated with enhanced cardiotoxicity; this toxicity can be avoided, however, by limiting the exposure to doxorubicin. The newer regimens have now been moved into phase III studies. Future progress for this disease will depend on the introduction of new agents. Two novel drugs are currently being investigated in randomised phase III trials as potentiators of Dox and/or paclitaxel. One is a monoclonal antibody from Genentech (Herceptin, trastuzumab) directed at the HER-2/neu oncogene, which is overexpressed in 〉25% of breast cancers [3]. Recent results indicate that Herceptin in combination with paclitaxel (or with a Dox plus cyclophosphamide regimen) induces a higher response rate (RR) and prolongs the time to disease progression when compared to chemotherapy alone. The second agent N,N-diethyl-2[4-(phenylmethyl)-phenoxyl] ethanamine.HCl (DPPE, BMS-217380-01), when combined with Dox, was associated with a higher RR than previously observed with Dox alone [4]. A randomised trial of Dox versus Dox plus DPPE is ongoing. The possible mechanisms underlying chemo-potentiation by these agents are discussed. As new anthracycline/taxane combinations establish themselves in earlier stages of the disease, the need for effective, non-cross resistant salvage regimens will emerge.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 72
    ISSN: 1569-8041
    Keywords: breast cancer ; Cowden disease ; Lhermitte Duclos
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 73
    ISSN: 1569-8041
    Keywords: anastrozole ; Arimidex® ; aromatase inhibitor ; breast cancer ; formestane ; oestradiol ; tolerability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: This study provides a direct randomized comparison of a new-generation, non-steroidal aromatase inhibitor, anastrozole (Arimidex®), with a steroidal aromatase inhibitor (formestane) with respect to oestrogen (oestradiol, oestrone, and oestrone sulphate) suppression and tolerability. Patients and methods: Sixty postmenopausal women with advanced breast cancer were randomized to receive either anastrozole 1 mg once daily orally (n = 29), or formestane 250 mg once every two weeks by intramuscular injection (n = 31). Treatment was continued until progression of disease or withdrawal from the study. The primary endpoints of this study were oestradiol suppression and tolerability. The secondary endpoints included oestrone and oestrone sulphate suppression. All laboratory analyses were conducted ‘blind’ of the randomized drug treatment. Results: Anastrozole produced a greater and more consistent suppression of oestradiol levels compared with formestane. Based on two- and four-week measurements, the mean fall from baseline (pre-dose) in oestradiol level was 79% and 58% in the anastrozole and formestane groups, respectively (P = 0.0001). After four weeks of treatment, oestrone and oestrone sulphate levels were also suppressed to a greater extent by anastrozole compared with formestane (oestrone: 85% versus67%, respectively, P = 0.0043; oestrone sulphate: 92% versus 67%, respectively, P = 0.0007). No statistical differences were seen between the two drugs in the incidence of adverse events. Conclusions: Anastrozole provides a more consistent and significantly more effective suppression of oestradiol compared with formestane. Similar results were observed for oestrone and oestrone sulphate. The clinical significance of these differences in total oestrogen suppression remains to be established.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 74
    Electronic Resource
    Electronic Resource
    Springer
    Annals of oncology 10 (1999), S. 121-127 
    ISSN: 1569-8041
    Keywords: breast cancer ; mammography ; prevention ; screening
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract From numerous studies on breast cancer it can be concluded that no single measure can lessen the burden of this frequent cancer in women in all developed countries. Complex strategies including primary prevention by identification of risk factors and their modification, secondary prevention by earlier detection and tertiary prevention by improving treatment outcome are needed to control the disease. Besides age, the established breast cancer risk factors include certain benign breast diseases, family history, ionising radiation, some reproductive factors and obesity. Primary prevention includes general recommendation for healthy lifestyle, e.g., avoidance of obesity, proper diet, physical activity and moderate alcohol consumption. Randomised controlled trials conducted in the USA, Canada, Scotland and Sweden have shown that regular mammography, alone or in combination with clinical examination, is effective in reducing mortality for about 30% in women over the age of 50, and much less in younger population. However, mammography screening has several drawbacks, the major being its tendency towards false positive and false negative results with all their potential psychosocial consequences. High quality assurance and control, as well as effective and readily available treatment, all of which demand high investments, are indispensable for good results. Even in the absence of organised screening, the availability of effective treatment may contribute to reduction in breast cancer mortality.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 75
    ISSN: 1569-8041
    Keywords: breast cancer ; cytomegalovirus pneumonia ; dexamethasone ; ganciclovir ; standard dose chemotherapy regimen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Cytomegalovirus (CMV) pneumonia in the setting of non-transplantation patients is a rarity. We present a case of CMV pneumonitis in a woman with stage IV breast cancer, with brain metastases, receiving both chemotherapy and systemic corticosteroids. A review of the literature reveals this as a unique case. Potential viral etiologies should therefore be considered in cancer patients with pneumonia receiving non-transplantation chemotherapy-regimens, particularly if steroids are a component of their therapy.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 76
    ISSN: 1569-8041
    Keywords: breast cancer ; docetaxel ; epirubicin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose: To determine the maximum tolerable dose (MTD) and the dose-limiting toxicity (DLT) of docetaxel (D) in combination with epirubicin (Epi) in patients with advanced breast cancer. Patients and methods: Forty-seven chemotherapy-naïve metastatic breast cancer patients aged 〈75 years with PS (WHO) 0–2 and adequate bone marrow, renal, liver and cardiac function, were enrolled in the study. Epi was given as a five-min bolus i.v. infusion on day 1 (d1) in escalated doses with increments of 10 mg/m2; D was given in a one-hour infusion after appropriate premedication on either day 1 or on day 2 in escalated doses with increments of 10 mg/m2. The patients' median age was 60 years, 42 (89%) had a PS (WHO) 0–1, 16 (34%) were premenopausal and 25 (53%) had visceral disease. Results: When the two drugs were given on the same day, the MTD1 was reached at the doses of Epi 60 mg/m2 and D 80 mg/m2; administration of G-CSF could not result in a dose intensification. When the drugs were given on two consecutive days, the MTD2 was reached at the doses of Epi 80 mg/m2 (d1) and D 90 mg/m2 (d2). The dose-limiting events were febrile neutropenia and grade 4 neutropenia, which developed in 30 (64%) patients during the study; among 227 delivered cycles grade 3–4 neutropenia occurred in 64 (28%) cycles but only 22 (10%) of them were complicated by fever. There were no septic deaths. Grade 1–2 neurosensory toxicity occurred in nine (19%) patients, mild edema in eight (17%) and allergic reactions in five (11%). Four (9%) patients presented a greater than 10% decrease of LVEF and treatment discontinuation was required in two of them; none of the patients developed congestive heart failure. Nevertheless, one patient suddenly died 10 days after treatment initiation of myocardial ischemia, and this death is considered treatment-related. Five (14.7%) complete and thirteen (38.2%) partial responses (ORR: 53.9%; 95% confidence interval: 36.1%–69.7%) were observed in 34 evaluable patients. Ten (29.4%) and six (17.6%) patients had stable and progressive disease, respectively. The median duration of response and time to tumor progression were five and seven months, respectively. The median survival has not yet been reached. Conclusions: The combination of epirubicin and docetaxel is a feasible and well tolerated regimen, but the MTD depends on the administration schedule of the drugs.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 77
    Electronic Resource
    Electronic Resource
    Springer
    Annals of oncology 10 (1999), S. 627-636 
    ISSN: 1569-8041
    Keywords: breast cancer ; depression ; diagnosis ; treatment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 78
    ISSN: 1569-8041
    Keywords: breast cancer ; paclitaxel ; phase I ; vinorelbine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: In vitro experiments suggest that administration of vinorelbine preceding paclitaxel results in synergistic cytotoxic effects. A phase I dose escalation trial of vinorelbine daily × 3 with paclitaxel on day 3 repeated every 28 days in metastatic breast cancer patients was completed. Patients and methods: Female patients, PS 0–2, without evidence of CNS disease or prior neuropathies were treated with vinorelbine at dose levels 7, 10, 13 mg/m2 per day and paclitaxel over three hours at dose levels of 135, 175, and 200 mg/m2. Results: Twenty-eight patients with six dose levels were studied. At dose level 1, patients developed intolerable but reversible neutropenia. Subsequent dose levels required filgrastim. Dose limiting toxicities were myalgia and fatigue at vinorelbine 13 mg/m2 /day and paclitaxel 200 mg/m2. Neuropathy was minor. Twelve of twenty-five patients with measurable disease had a rapid response which did not correlate with dose level. Conclusions: Sequential administration of these two agents demonstrates activity in breast cancer patients. Phase II dosing on this schedule should be vinorelbine 13 mg/m2/day × 3 and paclitaxel 175 mg/m2. With proper selection of patients, concern about neurologic toxicity should not impede future trials of vinorelbine with paclitaxel.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 79
    ISSN: 1573-4919
    Keywords: protein kinase A ; site-directed mutagenesis ; breast cancer ; growth arrest ; cAMP response element
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Expression of the RIα regulatory subunit of protein kinase A type I is increased in human cancer cell lines, in primary tumors, in cells after transformation, and in cells upon stimulation of growth. Ala99 (the pseudophosphorylation site) of human RIα was replaced with Ser (RIα-p) for the structure-function analysis of RIα. MCF-7 hormone- dependent breast cancer cells were transfected with an expression vector for the wild-type RIα or mutant RIα-p. Overexpression of RIα-P resulted in suppression of protein kinase A type II, the isozyme of type I kinase, production of kinase exhibiting reduced cAMP activation, and inhibition of cell growth showing an increase in G0/G1 phase of the cell cycle and apoptosis. The wild-type RIα overexpression had no effect on protein kinase A isozyme distribution or cell growth. Overexpression of protein kinase A type II regulatory subunit, RIIβ, suppressed RIα and protein kinase A type I and inhibited cell growth. These results show that the growth of hormone-dependent breast cancer cells is dependent on the functional protein kinase A type I.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 80
    ISSN: 1573-4919
    Keywords: progesterone receptor ; breast cancer ; steroid receptor agonists ; antagonists ; T47D cells ; RU486
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract T47D cells, cultured in medium containing serum stripped of endogenous steroids, proliferate in response to treatment with the progesterone receptor (PR) agonist, R5020 or the PR agonist/antagonist, RU486, whereas the full PR antagonist, ZK98299 has no proliferative effects. Under estrogenized conditions, all of the PR ligands tested inhibit cell growth [23]. In order to determine whether the levels or phosphorylation state of PR are reflected in the growth patterns of T47D cells, we monitored the effects of these PR ligands on the immunoblotted PR band intensities, the relative intensities, of PR-A and PR-B, and their phosphorylation states that are reflected in their altered mobility during SDS-PAGE. Under conditions where the PR ligands inhibit cell proliferation, each ligand had distinctively different qualitative and quantitative effects on PR. Short term treatment of the cells with R5020 or RU486 induced a characteristic phosphorylation-dependent upshift of both PR-A and PR-B. The phosphorylated PR was stable for up to 4 days after treatment of the cells with RU486, but was down regulated between 6-24 h after treatment with R5020. No replenishment of PR in cells treated with R5020 was detected. ZK98299, at concentrations tested, had no qualitative or quantitative effects on PR. Culturing cells for 8 days in medium containing steroid-depleted serum caused a significant reduction in the PR band intensity without causing a change in the ratio of PR-A and PR-B or their phosphorylation states. This decrease in the PR band intensity was reversed by maintaining the cells in 1 nM estrogen, but was potentiated by RU486 or ZK98299. These observations support the view that decreased PR levels may play a role in the stimulatory effects of R5020 and RU486 when cells are cultured under non-estrogenized conditions.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 81
    ISSN: 1573-4919
    Keywords: T47D cells ; breast cancer ; cellular proliferation ; progesterone ; estradiol ; steroid receptors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract We have examined the influence of progestins (progesterone, R5020) and antiprogestins (RU486, ZK98299, Org 31710 and Org 31806) on the rate of proliferation of wild type T47D cells cultured in whole fetal bovine serum (FBS) or in single charcoal stripped fetal bovine serum (SSFBS). All of the progesterone antagonists RU486, ZK98299 and two novel antiprogestins Org 31710 and Org 31806 inhibited cell proliferation when cells were cultured in FBS. In contrast, all of the antiprogestins with the exception of ZK98299 enhanced cell growth when cells were cultured in SSFBS. This stimulatory effect of RU486 was observed only at a high concentration of the ligand (1 μM). The effect of R5020, however, was concentration independent. The number of cells in the presence of RU486 was ~ 600% followed by R5020 ~ 400% above control values after a 28 day culturing period. In contrast, when the cells were grown in the presence of medium containing non-stripped whole serum, RU486 inhibited the extent of cell proliferation by 45%. Estradiol (E2) stimulated the rate of proliferation in cells cultured in SSFBS. Similar to when cells were cultured in whole serum, the antiprogestins inhibited cell growth in E2-supplemented SSFBS. Detection of the growth enhancement effects of progesterone receptor (PR) ligands such as RU486 and R5020 on the cells grown in charcoal-stripped medium appear to require the removal of E2 by charcoal stripping of the serum.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 82
    ISSN: 1432-2277
    Keywords: Key words Liver transplantation ; Survival ; Amino acids ; Organ preservation ; Primary nonfunction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract There are too few reliable markers by which one can predict future function of a liver before implantation. Consequently, the purpose of this study was to test the hypothesis that amino acids in rinse–effluents could predict transplant outcome in marginal fatty livers from rats. Amino acids were measured in the rinse effluent from the livers immediately after harvest and graft preparation or cold storage. Amino acids in the effluent were twice as high in ethanol-treated animals compared to those in nonfatty controls. Ethanol-treated fatty livers survived for no longer than 7 days after transplantation while 83 % of nonfatty controls survived (P 〈 0.05). In subsequent studies, the cold-storage time was decreased to 6 h to determine whether failing fatty livers released more amino acid than grafts that would function normally. There was a significant increase in amino acids in the effluent of fatty grafts compared to controls. Moreover, the sum of the four selected amino acids (alanine, valine, histidine, leucine) was lower than 23 nmol/g liver in functional livers, whereas failing grafts had totals significantly higher than 25 nmol/g liver. The sum of the four amino acids correlated well with 24 h post-transplant serum AST levels (r = 0.78, P 〈 0.0001). So we can conclude that amino acid release can serve as a useful marker of graft viability and reliably predicts survival.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 83
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical chemistry accounts 101 (1999), S. 186-193 
    ISSN: 1432-2234
    Keywords: Key words: Solvent accessibility ; Logistic function ; Hydrophobicity ; Burial index ; Amino acids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract. For predicting solvent accessibility from the sequence of amino acids in proteins, we use a logistic function trained on a non-redundant protein database. Using a principal component analysis, we find that the prediction can be considered, in a good approximation, as a monofactorial problem: a crossed effect of the burial propensity of amino acids and of their locations at positions flanking the amino acid of interest. Complementary effects depend on the presence of certain amino acids (mostly P, G and C) at given positions. We have refined the predictive model (1) by adding supplementary input data, (2) by using a strategy of prediction correction and (3) by adapting the decision rules according to the amino acid type. We obtain a best score of 77.6% correct prediction for a relative accessibility of 9%. However, compared to trivial strategy only based upon the frequencies of buried or exposed residues, the gain is less than 4%.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 84
    ISSN: 1439-6327
    Keywords: Key words Endurance exercise ; Amino acids ; Serotonin ; Central fatigue ; Overtraining
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The neurotransmitter serotonin (5-hydroxytryptamine, 5-HT) has been shown to modulate various physiological and psychological functions such as fatigue. Altered regulation of the serotonergic system has been suggested to play a role in response to exercise stress. In the present study, the influence was investigated of acute endurance exercise and short-term increase in the amount of training on the concentrations of the 5-HT precursor tryptophan (TRP), of prolactin (PRL) and of branched-chain amino acids (BCAA) in the blood, as well as on the binding of [3H]ketanserin to the serotonin-2A (5-HT2A) receptors on platelets. Nine healthy endurance-trained men were tested the day before (I) and after (II) a 9-day training programme. Samples of venous blood were drawn after an overnight fast and following 5 h of cycling. Fasted and post-exercise plasma concentrations of free TRP, BCAA and free TRP:BCAA ratio did not differ between I and II. A significant decrease of plasma BCAA (P 〈 0.01) and significant augmentations of plasma free TRP, free TRP:BCAA ratio and PRL (P 〈 0.01) were found post-exercise. The increase in plasma PRL was smaller in II compared with I. Acute endurance exercise reduced the density of platelet 5-HT2A receptor [3H]ketanserin binding sites at I and II (P 〈 0.05). The basal density of the binding sites and the affinity of [3H]ketanserin for these binding sites were unaffected by an increase in the amount of training. The present results support the hypothesis that acute endurance exercise may increase 5-HT availability. This was reflected in the periphery by increased concentration of the 5-HT precursor free TRP, by increased plasma PRL concentration, and by a reduction of 5-HT2A receptors on platelets. It remains to be resolved whether these alterations in the periphery occur in parallel with an increase in the availability of 5-HT in the brain.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 85
    Electronic Resource
    Electronic Resource
    Springer
    Investigational new drugs 17 (1999), S. 417-427 
    ISSN: 1573-0646
    Keywords: breast cancer ; growth factors ; metalloproteinase ; angiogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Abstract A better understanding of the biology of breast cancer should leadto the rational development of new treatments and the ability tocustomize therapy for individual patients. Though promising intheory, translating advances in biological knowledge to the clinichas been difficult. Recently several areas of research haveproduced treatments which have entered clinical trials; three willbe reviewed here. The growth of breast cancer is regulated bygrowth factors and their receptors; amplification or overexpressionis associated with poor prognosis. As such inhibition of growthfactors and/or growth factor receptors may provide an idealtherapeutic target. Herceptin binds to c-erbB-2, a member of theepidermal growth factor receptor family. Significant responses wereseen in patients with c-erbB-2 overexpressing breast cancer withHerceptin administered as a single agent or in combination withchemotherapy. Herceptin was approved by the Food and DrugAdministration in late 1998. Breast cancer invasion and metastasisrequires degradation of the surrounding basement membrane by matrixmetalloproteinases and other proteolytic enzymes. Syntheticinhibitors of these enzymes are now in clinical trials. Breastcancers must stimulate angiogenesis, the growth of new bloodvessels, in order to grow beyond a few millimeters in diameter.This nascent vascular network provides another opportunity fortherapy. Preclinical models support the critical role ofangiogenesis and the therapeutic benefit of angiogenesisinhibition; clinical trials are underway.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 86
    Electronic Resource
    Electronic Resource
    Springer
    Clinical & experimental metastasis 17 (1999), S. 67-72 
    ISSN: 1573-7276
    Keywords: breast cancer ; extracellular matrix ; gelatinase ; invasion ; matrix metalloproteinase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Seprase is a serine protease that is integral to the plasma membrane and is overexpressed by invasive tumor cells (Piñeiro-Sánchez et al., J Biol Chem 1997; 272: 7595–601; Monsky et al., Cancer Res 1994; 54: 5702–10). Seprase activity is most often assessed by zymography, which is not a quantitative assay. This study establishes a relatively simple and quantitative method for determining seprase activity. The degradation of a 3H-gelatin substrate is measured in the presence of 5 mM EDTA which inhibits matrix metalloproteinases but not seprase. The quantitative character of the assay was demonstrated using partially purified seprase from chicken embryos, a preparation that lacks detectable matrix metalloproteinase activity. In this assay, release of 3H-gelatin fragments is linear over time for 1.5 μg/assay seprase concentration as well as for preparations concentrated or diluted by five fold (7.5 μg/assay and 0.3 μg/assay respectively). Additional experiments were performed to validate the quantification of seprase activity using the radiographic assay by comparing the results to zymography. Exposure to 22 or 37 °C results in maximal seprase activity while exposure to 80 or 100 °C completely abolishes seprase activity in both zymography and the radiographic assay. Exposure to 60 °C abolished seprase activity as judged by zymography, but about 50% gelatinase activity was observed using the 3H-gelatin substrate. Immunopreciptiation with seprase-specific antibody specifically removed seprase and lowered the seprase activity remaining in the extracts as judged by both assays. Investigation of the seprase that was partially purified from human breast cancer tissue revealed that its specific activity (cpm gelatin fragments released/ {mg protein×h}) is five times greater than that of seprase purified from chicken embryos. This assay will be useful for determining the seprase activity in extracts of tumor tissues and cells as well as for identifying inhibitors of seprase.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 87
    Electronic Resource
    Electronic Resource
    Springer
    Plant foods for human nutrition 54 (1999), S. 375-380 
    ISSN: 1573-9104
    Keywords: 7S/11S ratios ; Amaranth ; Amino acids ; Nutrition ; Varieties
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract 7S/11S seed globulin ratios were determined for sevencurrently available Amaranthus hybrid linesi.e., Amaranthus K266, K283, K343, K432, K433,K436 and MT-3. Of the seven Amaranthus linesinvestigated, four lines had 7S/11S globulin ratiosranging from 0.47 to 0.81, while three lines werefound to contain exclusively the 11S globulin form. In general, 7S globulins contained lower levels ofessential amino acids such as tryptophan, methionine,lysine, histidine, phenylalanine, valine andisoleucine than the 11S globulins.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 88
    ISSN: 1573-9104
    Keywords: Amino acids ; Celiac disease ; Cells ; Cereals ; Prolamines ; Quinoa seeds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The edible seeds of the quinoa plant contain small quantities of alcohol-soluble protein which, after peptic-tryptic digestion, are unable to agglutinate K562(s) cells. When separated by affinity chromatography on sepharose-6B coupled with mannan, peptic-tryptic digest separated in two fractions. Fraction B peptides (about 1% of total protein) were shown to agglutinate K562(s) cells at a very low concentration, whereas peptides in fraction A and in the mixed fraction A+B were inactive, suggesting that fraction A contains protective peptides that interfere with the agglutinating activity of toxic peptides in fraction B.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 89
    Electronic Resource
    Electronic Resource
    Springer
    Plant foods for human nutrition 54 (1999), S. 345-352 
    ISSN: 1573-9104
    Keywords: Amino acids ; Antinutritional factors ; Protein fractionation ; Proximate composition ; Teramnus labialis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Seeds of Teramnus labialis (L.) Spreng.(Fabaceae), used as food by Malayali tribals in theKollihills of Salem District, Tamil Nadu in SouthIndia, were investigated for their nutritional value. These seeds were analyzed for proximate composition,total (true) seed proteins, seed proteinfractions, amino acid composition, fatty acidcomposition, minerals and antinutritional factors. Crude protein, crude fat, ash, and nitrogen freeextracts constituted 22.86%, 6.10%, 4.62%, and,58.15%, respectively, of the seed weight. The caloricvalue of 100 g dry matter of seed material was 378.94kcal. The essential amino acids lysine, leucine +isoleucine, arginine, valine and histidine werepresent in relatively large quantities. Theunsaturated fatty acids constituted more than 60% ofthe crude fat. Concentrations of minerals such aspotassium, magnesium, calcium, and, phosphorus werehigh. Antinutritional factors such as total freephenols, tannins, L-DOPA, hydrogen cyanide andphytic acid were present in minute quantities. Theseantinutritional factors are potentially eliminated using the conventional method of soaking the seeds in water,boiling with water and decanting prior to consumption.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 90
    ISSN: 1573-6903
    Keywords: Amino acids ; synaptosomes ; epilepsy ; glutamate ; GABA ; glutamine ; taurine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We have studied the levels of neuroactive amino acids in synaptosomes (P2 fraction) isolated from brain tissue of ten patients with medically intractable epilepsy who were undergoing temporal lobectomy. First, lateral temporal tissue (nonfocal) was removed followed by medial temporal tissue (focal). A synaptosomal fraction (P2) was immediately prepared from each tissue and analyzed for free amino acid concentrations. Statistically significant reductions were seen in glutamine and GABA concentrations in focal tissue compared to nonfocal tissue. The ratio of excitatory amino acids (aspartate and glutamate) to inhibitory amino acids (taurine and GABA) was significantly higher in focal tissue compared to nonfocal. The glutamine/glutamate ratio was significantly reduced. These data support the hypothesis that alterations in the balance between excitatory and inhibitory amino acids may be involved in the expression of epilepsy.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 91
    ISSN: 1573-7217
    Keywords: breast cancer ; microsatellites ; prognostic factors ; 17q21 region ; 13q12‐13 region
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Loss of heterozygosity (LOH) in loci of the 17q21 and 13q12‐13 regions can collaborate in the inactivation of BRCA1, BRCA2, and possibly other genes implicated in the pathogenesis of breast carcinomas. We investigate allelic losses in microsatellites of the BRCA1 and BRCA2 regions, and their correlations with seven pathologic parameters in 140 breast carcinomas. Those cases showing LOH in the region of the RB gene, 13q14, were excluded from the study. The LOH analysis was performed by amplifying DNA by PCR, using four markers of the 17q21 region (D17S856, D17S855, D17S1323, and D17S1327) and four markers of the 13q12‐13 region (D13S290, D13S260, D13S310, and D13S267). LOH in the BRCA1 region was found in 47% of tumors, correlating significantly with estrogen receptor content (p = 0.025), progesterone receptors (p = 0.004), higher grade (p = 0.0008), peritumoral vessel invasion (p = 0.001), and lymph node metastases (p = 0.002). When we excluded the cases with LOH in the BRCA2 region and those not informative for it, the significance disappeared. In the BRCA2 region, a rate of LOH of 51% was found; it correlated significantly with estrogen receptor content (p = 0.002), progesterone receptors (p =0.03), peritumoral vessel invasion (p = 0.005), higher grade (p =0.002), and lymph node metastases (p = 0.001). When cases with BRCA1 losses and those not informative were excluded, again the significance disappeared. Concomitant losses in the BRCA1 and BRCA2 regions were found in 32% of cases, correlating significantly with lymph node metastases (p = 0.0002), estrogen receptor content (p = 0.003), progesterone receptors (p = 0.001), histologic grade (p =0.01), and peritumoral vessel invasion (p = 0.0004). These results suggest that concomitant losses in both regions could have a functional effect, influencing the presence of a poor tumor pathophenotype in breast carcinomas.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 92
    ISSN: 1573-7217
    Keywords: breast cancer ; neoadjuvant therapy ; FNA ; estrogen receptor ; progesterone receptor ; p53 ; Bcl‐2 ; Ki67 ; SPF ; ploidy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Aim: To quantify the changes in biological molecular markers during primary medical treatment in patients with operable breast cancer and to assess their possible relationship with response to treatment. Methods: The treatment group consisted of 31 patients with operable breast carcinomas, median age 57 years (range 41–67), treated with four 3‐weekly cycles of chemotherapy with Mitoxantrone, methotrexate (± mitomycin C), and tamoxifen before surgery. Fine needle aspiration (FNA) was used to obtain samples from patients prior to and at 10 or 21 days post‐treatment. The following molecular markers were assessed: estrogen receptor (ER), progesterone receptor (PgR), p53, Bcl‐2, and Ki67 measured by immunocytochemistry, and ploidy and S‐phase fraction (SPF) by flow cytometry. To evaluate the reproducibility of the technique, repeat FNA was performed in a separate non‐treatment control group of 20 patients and the same molecular markers assessed, two weeks after the first sample with no intervening treatment. Results: The non‐treatment control group showed a high reproducibility for the measurement of molecular markers from repeat FNA. In the treatment group there was a non‐significant reduction in SPF and a significant reduction (p = 0.005) in Ki67. Patients who responded to neoadjuvant therapy were more likely to have a reduction in these two markers than those who failed to respond. Similarly, a reduction in ER scores was observed between the first and second samples (p = 0.04). For PgR, the change between the first and second samples was not significant although there was a significant difference between responders and non‐responders (p = 0.03). All nine patients with an increase in PgR were responders. No significant changes in p53 or Bcl‐2 were observed during treatment. Conclusion: Molecular markers can be adequately measured from FNA samples prior to and during neoadjuvant therapy. Changes in cellular proliferation and hormone receptors have been shown that may be related to tumour response. These relationships should be assessed in a larger cohort of patients.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 93
    ISSN: 1573-7217
    Keywords: HPV 16 ; breast cancer ; CIN III ; PCR ; southern blot ; in situ hybridization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Women with both a history of high grade cervical intraepithelial neoplasia (CIN III) and breast carcinoma as second primary cancer were selected for studying the presence of HPV in breast carcinomas. Paraffin embedded material from 38 patients with 41 breast carcinoma cases after CIN III were examined by polymerase chain reaction (PCR) and in situ hybridization. By PCR we detected HPV 16 DNA in 19 out of 41 cases (46%) of the breast carcinomas. One case proved to be HPV 16 positive also by in situ hybridization. HPV 16 was also detected in 32 out of the 38 patients with CIN III (84%). All HPV 16 positive breast carcinomas were HPV 16 positive in their corresponding CIN III lesions. Eight patients with diagnosed breast cancer before the CIN III lesions were used as controls. None of these had HPV positive breast carcinomas. No cases were positive for HPV 11, 18, or 33. HPV 16 was detected in the primary tumours, in local metastases from HPV 16 positive tumours, in a distant HPV 16 positive breast carcinoma metastasis to the colon, and in other primary cancers in patients with HPV 16 positive breast carcinomas and HPV 16 positive CIN III. Estrogen and progesterone receptors were quantified in the HPV positive and HPV negative breast carcinomas, and there was no significant difference in the fraction positive in the two groups. Oncogenic HPV DNA might be transported from an original site of infection to other organs by blood or lymph, and possibly be a factor in the development of cancer in different organs.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 94
    ISSN: 1573-7217
    Keywords: age of diagnosis ; ascertainment ; breast cancer ; genetic anticipation ; prospective cohort family study
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Genetic anticipation is characterized by an earlier age of disease onset, increased severity, and a greater proportion of affected individuals in succeeding generations. The discovery of trinucleotide repeat expansion (TRE) mutations as the molecular correlate of anticipation in a number of rare Mendelian neurodegenerative disorders has led to a resurgence of interest in this phenomenon. Because of the difficulties presented to traditional genetics by complex diseases, the testing for genetic anticipation coupled with TRE detection has been proposed as a strategy for expediting the identification of susceptibility genes for complex disorders. In the case of breast cancer, a number of previous studies found evidence consistent with genetic anticipation. It is known that a proportion of such families are linked to either BRCA1 or BRCA2, but no TRE mutations have been identified. It has been shown that the typical ascertainment employed in studies purporting to demonstrate genetic anticipation combined with unadjusted statistical analysis can dramatically elevate the type I error. We re‐examine the evidence for anticipation in breast cancer by applying a new statistical approach that appears to have validity in the analysis of anticipation to data ascertained from a recent follow‐up of a large prospective cohort family study of breast cancer. Using this approach, we find no statistically significant evidence for genetic anticipation in familial breast cancer. We discuss the limitations of our analysis, including the problem of adequate sample size for this new statistical test.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 95
    ISSN: 1573-7217
    Keywords: breast cancer ; cell interactions ; 1,25‐dihydroxyvitamin D3 ; fibroblast ; normal epithelial cell
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Mesenchymal‐epithelial interactions are of paramount importance during normal and tumoral breast developments. We have investigated the paracrine growth regulation of normal and tumoral breast epithelial cells by fibroblasts derived from normal or pathological breast tissues. In some cases, breast cancer MCF‐7 cells or normal epithelial cells in primary culture were cocultured with fibroblasts in a Transwell system allowing diffusible factor exchanges. Alternatively, conditioned medium produced by fibroblast cultures was added to epithelial cell cultures. Fibroblasts were shown to stimulate the proliferation of normal and carcinoma cells through paracrine mechanisms. However, the paracrine exchanges appeared to be different in normal versus tumoral breast epithelial cell growth regulation. Moreover, vitamin D‐related compounds that have been proposed as anti‐tumoral drugs were studied for their ability to affect normal and tumoral mammary epithelial cell proliferation and to interfere with the growth‐regulatory activity of fibroblasts. Whereas vitamin D compounds inhibited MCF‐7 cell growth, they led to a marked stimulation of the proliferation of normal mammary epithelial cells. Moreover, it was shown that the vitamin D analog EB 1089 can block the mitogenic effect of fibroblast‐conditioned medium on tumoral but not normal breast epithelial cells. The differential effects of vitamin D compounds on cell proliferation provide further data in favor of the different behaviours of normal and tumoral mammary epithelial cells. The potential therapeutic use of vitamin D derivatives in the treatment of breast cancer is supported by these results but their growth‐stimulatory properties on normal epithelial cells cannot be overlooked.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 96
    ISSN: 1573-7217
    Keywords: apoptosis ; Bax ; Bcl‐2 ; breast cancer ; chemotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Optimizing chemotherapeutic drug delivery strategies relies, in part, on identification of the most clinically effective sequence, dose, and duration of drug exposure. The combination of dose intensive etoposide (VP‐16) followed by cyclophosphamide has clinical efficacy in the treatment of advanced breast cancer. However, molecular mechanisms that underlie the effectiveness of this combination of chemotherapeutic agents have not been investigated. In this study we investigated regulation of BAX and BCL‐2 expression by VP‐16 and cyclophosphamide as a potential mechanism for the induction of breast cancer cell death induced by this regimen. There was a dose and time dependent increase in BAX expression in the breast cancer cell lines MCF‐7, MDA‐MB‐435S, and MDA‐MB‐A231 following in vitro treatment with 50–100 μM VP‐16. Elevation of BAX protein expression in the presence of VP‐16 alone did not correlate with reduced viability or induction of apoptosis in MCF‐7, MDA‐MB‐435S, or MDA‐MB‐A231. VP‐16 did effectively block the breast cancer cell lines evaluated (MCF‐7 and MDA‐MB‐435S) at G2/M phase of the cell cycle, confirming activity of the drug in vitro. MCF‐7 and MDA‐MB‐435S cells that were pre‐treated with VP‐16 and subsequently exposed to 1.0–12.0 μg/m1 4‐hydroperoxycyclophosphamide (4HC), an active metabolite of cyclophosphamide, had markedly reduced viability when compared to matched controls treated with either VP‐16 or 4HC individually. Consistent with this loss of viability, exposure of all three cell lines to the combination of VP‐16 and 4HC resulted in higher BAX protein levels than those observed following treatment with either single agent. This combination of chemotherapeutic agents also resulted in reduced BCL‐2 expression. These observations suggest that combination chemotherapy may derive its efficacy, in part, through coordinated regulation of specific gene products associated with apoptosis. Characterization of molecular events that underlie susceptibility of specific tumor cells to combination chemotherapeutic regimens may lead to additional improvements in treatment strategies for this disease.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 97
    ISSN: 1573-7217
    Keywords: breast cancer ; cathepsin D ; immunohistochemistry ; protease
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This study was aimed at investigating the influence of cathepsin D (CD) expression by cancer cells and stromal cells on breast cancer prognosis. This is a study of 1348 node‐positive (NPBC) and node‐negative (NNBC) breast cancers diagnosed between 1980 and 1986 and with a minimum follow‐up of 5.2 years. CD expression was assessed by immunohistochemistry on archival material using a polyclonal antibody. The expression by cancer and stromal cells was assessed separately and correlated with distant metastasis free (DMFS) and overall survival (OS). Cancer cells expressed CD (more than 10% cells expressing CD) in 38.9% of cases and reactive stromal cells in 43.6%. CD expression by reactive stromal cells, and not cancer cells, correlated with several factors of poor prognosis by cancer cells. A strong association was also found with expression of other proteases (stromelysin‐3, gelatinase A, and urokinase Plasminogen Activator) by these same reactive stromal cells. CD expression by cancer cells did not predict DMFS or OS but, by univariate analysis, CD expression by reactive stromal cells was associated with earlier recurrence and shorter survival in NNBC (p = 0.0425) and NPBC patients submitted to adjuvant chemotherapy (p = 0.0234). However, CD expression by reactive stromal cells remained a significant predictor of recurrence by multivariate analyses only in a subgroup of NPBC submitted to adjuvant chemotherapy. Overall, those data support the concept that proteases produced by reactive stromal cells are under cancer cell stimulation and that CD by stromal cells, and not cancer cells, influences the prognosis, but only in a subgroup of patients with breast cancer.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 98
    ISSN: 1573-7217
    Keywords: breast cancer ; endocrine therapy ; FACT‐B ; FACT‐ES ; quality of life
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Existing quality of life instruments do not include adequate items to measure the side effects and putative benefits of hormonal treatments given in breast cancer. We report the development and validation of an 18 item endocrine subscale (ES) to accompany a standardised breast cancer quality of life measure, the Functional Assessment of Cancer Therapy (FACT‐B) [1]. The FACT‐ES (FACT‐B plus ES) was tested initially on 268 women with breast cancer receiving endocrine treatments. Alpha coefficients for all subscales demonstrated good internal consistency (range α = 0.65–0.87). Test‐retest reliability of the ES indicated good stability (r = 0.93, p 〈 0.001). Advanced breast cancer patients' quality of life was high, showing the efficacy of endocrine therapy, but women with primary disease reported better physical, social, and functional well‐being and fewer breast cancer concerns. Most frequently reported symptoms were loss of sexual interest (31%), weight gain (25%), and hot flushes (24%). Significant differences were found between treatment groups for hot flushes and vaginal dryness. Two assessments of the instrument's responsiveness to change were made; 32 women in a clinical trial of endocrine therapy and 18 women without breast cancer taking HRT completed the FACT‐ES at baseline, 4, 8, and 12 weeks. Trial patients reported significantly more symptoms at 8 and 12 weeks than at baseline. Women taking HRT reported significantly fewer or less severe symptoms than at baseline. In conclusion the FACT‐ES has acceptable validity and reliability and is sensitive to clinically significant change, making it suitable for clinical trials of endocrine therapy.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 99
    ISSN: 1573-7217
    Keywords: breast cancer ; ICI 182 ; 780 ; IGFBPs ; tamoxifen resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Earlier studies in our laboratory demonstrated that the steroidal antiestrogen ICI 182,780 is very effective in abolishing the tamoxifen‐resistant proliferation of MCF 7/5‐23 cells [1]. In addition, preliminary binding studies showed that ICI 182,780 increased the binding of insulin‐like growth factor (IGF)‐I to the MCF 7/5‐23 cells, although this finding was not the result of an increase in the expression of the insulin‐like growth factor‐I receptor (IGF‐IR). Hence, we reasoned that the inhibition of tamoxifen‐resistant cell growth by ICI 182,780 might have been due to increased expression of insulin‐like growth factor binding proteins (IGFBPs). We observed the up‐regulation of non‐insulin‐suppressible IGF‐I binding in both the tamoxifen‐sensitive MCF 7/5‐21 cell line (1.5‐fold) and the tamoxifen‐resistant MCF 7/5‐23 cell line (2.5‐fold) after 5 days of treatment with ICI 182,780 (10−7 M) in serum‐free medium, suggesting a role for cell‐associated IGFBPs. Affinity cross‐linking experiments confirmed the presence of an IGF‐I:IGFBP complex of approximately 38‐kDa in tamoxifen or ICI 182,780‐treated cells. Western ligand blots showed higher levels of a soluble 30‐kDa IGFBP in media conditioned by either of the subclones that had been treated with ICI 182,780, an effect consistently opposed by estrogen (E2:10−9 M). RT‐PCR showed higher levels of IGFBP‐5 mRNA than any of the other known IGFBPs, suggesting that this was the major IGFBP subtype. The protein was subsequently identified by Western immunoblotting as IGFBP‐5. In conclusion, we postulate that this may be a mechanism contributing to the greater potency of ICI 182,780 in the growth inhibition of the MCF 7/5‐23, tamoxifen‐resistant cell line.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 100
    ISSN: 1573-7217
    Keywords: breast cancer ; cost effectiveness ; dense breasts ; mammographic parenchymal patterns ; Sestamibi scintimammography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The potential impact of Sestamibi scintimammography (SSMM) on the cost effective management of women with dense breasts is not known. This study addresses this issue quantitatively by examining the impact of SSMM based screening strategies on the ∼3,000,000 women over 40 with very dense breasts (DY patterns) without palpable masses and who have had one or more prior mammograms, who undergo routine screening each year. Quantitative decision tree sensitivity analysis was used to compare the conventional mammography (MM) strategy (strategy A), which does not subject patients with negative mammograms to any further examination until their next screening, with two decision strategies for screening with SSMM SSMM after a negative mammogram (strategy B) or SSMM as the only screening test for women already identified as having dense breasts by a previous mammogram (strategy C). Cost effectiveness was measured by calculating the incremental cost effectiveness ratio (ICER) of strategies B and C, which is the cost of achieving an additional year of life in the screening population by choosing a SSMM based decision strategy rather than the conventional strategy. Strategies B and C reduced the number of false negative diagnoses by 62% and 8%, respectively. The ICER was $632,000 and $3.18M per life year for strategy B and C, respectively. To be cost effective, the pre‐test probability of cancer in the study population must be greater than 3% for strategy B or the cost of SSMM must be less than $50 for strategy C. These results show the ICER of an SSMM based breast cancer screening strategy in the management of patients with dense breasts is not currently within the range (∼$50,000 per year life saved) of other commonly performed medical interventions that are considered cost effective.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...