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  • 1
    Electronic Resource
    Electronic Resource
    Carboxyfullerene Prevents Iron-Induced Oxidative Stress in Rat Brain (1999)
    Oxford UK : Blackwell Science Ltd
    Journal of neurochemistry 72 (1999), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: Carboxyfullerene, a water-soluble carboxylic acid derivative of a fullerene, was investigated as a protective agent against iron-induced oxidative stress in the nigrostriatal dopaminergic system of anesthetized rats. Intranigral infusion of exclusive carboxyfullerene did not increase lipid peroxidation in substantia nigra or deplete dopamine content in striatum. Infusion of ferrous citrate (iron II) induced degeneration of the nigrostriatal dopaminergic system. An increase in lipid peroxidation in substantia nigra as well as decreases in K+-evoked dopamine overflow and dopamine content in striatum were observed 7 days after the infusion. Co-infusion of carboxyfullerene prevented iron-induced oxidative injury. Furthermore, tyrosine hydroxylase-immunoreactive staining showed that carboxyfullerene inhibited the iron-induced loss of the dopaminergic nerve terminals in striatum. The antioxidative action of carboxyfullerene was verified by in vitro studies. Incubation of brain homogenates increased the formation of the Schiff base fluorescent products of malonaldehyde, an indicator of lipid peroxidation. Both autooxidation (without exogenous iron) and iron-induced elevation of lipid peroxidation of brain homogenates were suppressed by carboxyfullerene in a dose-dependent manner. Our results suggest that intranigral infusion of carboxyfullerene appears to be nontoxic to the nigrostriatal dopaminergic system. Furthermore, the potent antioxidative action of carboxyfullerene protects the nigrostriatal dopaminergic system from iron-induced oxidative injury.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1471-4159.1999.721634.x
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  • 2
    Electronic Resource
    Electronic Resource
    Immune Deviation during the Induction of Tolerance by way of Nasal Installation. (1996)
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 778 (1996), S. 0 
    Details
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-6632.1996.tb21158.x
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  • 3
    Electronic Resource
    Electronic Resource
    Down regulation of bcl-2 by p53 in nasopharyngeal carcinoma and lack of detection of its specific t(14;18) chromosomal translocation in fixed tissues (1996)
    Oxford, U.K. and Cambridge, USA : Blackwell Science Ltd
    Histopathology 28 (1996), S. 0 
    Details
    ISSN: 1365-2559
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: High levels of bcl-2 protein have been found in a wide variety of human cancers. Since p53 gene inactivation occurs in over half of human cancers, it is possible that loss of p53-mediated repression of bcl-2 gene expression accounts, at least in part, for the frequent abnormalities in bcl-2 protein production seen in tumours. By using immunohistochemical methods, we have analysed thirty-three nasopharyngeal carcinomas for p53 and bcl-2 expression. We found an inverse correlation between the expression of these two proteins (P 〈 0.001). Moreover, we utilized universal oligonucelotide primers of a region 5′ to the bcl-2 MBR and at the 3′ end of JH segments to initiate a DNA polymerase chain reaction that amplified these bcl-2-JH junctures. Of the twelve nasopharyngeal carcinomas expressing bcl-2, none showed a t(14;18) chromosome translocation. These findings may indicate potential mechanisms by which bcl-2 regulates apoptosis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2559.1996.d01-431.x
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  • 4
    Electronic Resource
    Electronic Resource
    Regulation of tomato fruit growth by epidermal cell wall enzymes (1998)
    Oxford, UK : Blackwell Science Ltd, UK
    Plant, cell & environment 21 (1998), S. 0 
    Details
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Water relations of tomato fruit and the epidermal and pericarp activities of the putative cell wall loosening and tightening enzymes Xyloglucan endotransglycosylase (XET) and peroxidase were investigated, to determine whether tomato fruit growth is principally regulated in the epidermis or pericarp. Analysis of the fruit water relations and observation of the pattern of expansion of tomato fruit slices in vitro, has shown that the pericarp exerts tissue pressure on the epidermis in tomato fruit, suggesting that the rate of growth of tomato fruit is determined by the physical properties of the epidermal cell walls. The epidermal activities of XET and peroxidase were assayed throughout fruit development. Temporal changes in these enzyme activities were found to correspond well with putative cell wall loosening and stiffening during fruit development. XET activity was found to be proportional to the relative expansion rate of the fruit until growth ceased, and a peroxidase activity weakly bound to the epidermal cell wall appeared shortly before cessation of fruit expansion. No equivalent peroxidase activity was detected in pericarp tissue of any age. It is therefore plausible that the expansion of tomato fruit is regulated by the combined action of these enzyme activities in the fruit epidermis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-3040.1998.00308.x
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  • 5
    Electronic Resource
    Electronic Resource
    Sugar uptake by protoplasts isolated from tomato fruit tissues during various stages of fruit growth (1997)
    Oxford, UK : Blackwell Publishing Ltd
    Physiologia plantarum 101 (1997), S. 0 
    Details
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The uptake of radioactive glucose and sucrose by protoplasts isolated from pericarp and placenta tissues of tomato (Lycopersicon esculentum cv. Counter) fruit was investigated in relation to the dry matter accumulation rates of these tissues. Uptake of glucose by protoplasts isolated from pericarp tissue was highest in fruit of around 20 g fresh weight or 25 days after anthesis. Sucrose uptake by pericarp protoplasts was lower than that of glucose and did not show a peak of uptake. The maximum rate of glucose uptake by protoplasts from the pericarp was at the time when the tomato fruit was accumulating dry matter at the highest rate. Glucose uptake by placenta protoplasts was lower and at a similar level as sucrose.Protoplast uptake of glucose, but not of sucrose, was partially inhibited by (1) p-chloromercuribenzene sulphonic acid, a sulphydryl group modifier; (2) erythrosin B, an H+-ATPase inhibitor; and (3) valinomycin, a K+-ionophore, suggesting that membrane transport of glucose by tomato fruit sink cells may be a carrier-mediated, energy-dependent process.The main route of carbohydrate accumulation by tomato fruit during the period of rapid fruit growth may be by cleavage of sucrose by apoplastic acid invertase prior to hexose transport across the plasma membrane.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1399-3054.1997.tb01034.x
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  • 6
    Electronic Resource
    Electronic Resource
    Properties of proton and sugar transport at the tonoplast of tomato (Lycopersicon esculentum) fruit (1995)
    Oxford, UK : Blackwell Publishing Ltd
    Physiologia plantarum 94 (1995), S. 0 
    Details
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Tonoplast vesicles were isolated from tomato (Lycopersicon esculentum Mill.) fruit pericarp and purified on a discontinuous sucrose gradient. ATPase activity was inhibited by nitrate and bafilomycin A1 but was insensitive to vanadate and azide. PPase hydrolytic activity was inhibited by NaF but was insensitive to nitrate, bafilomycin A1 vanadate and azide. Kimetic studies of PPase activity gave an apparent Km, for PP3 of 18 μM. Identical distributions of bafilomycin- and NO3-sensitive ATPase activities within continuous sucrose density gradients, confirmed that bafilomycin-sensitive ATPase activity is a suitable marker for the tonoplast. By comparing the distribution of bafilomycin-sensitive ATPase activity with that of PPase activity, it was possible to locate the PPase enzyme exclusively at the tonoplast. The apparent density of the tonoplast did not change during fruit development. Measurements of tonoplast PPase and ATPase activities during fruit development over a 35-day period revealed an 80% reduction in PPase specific activity and a small decrease in ATPase specific activity. ATP- and PP1-dependent ΔpH generation was measured by the quenching of quinacrine fluorescence in tonoplast vesicles prepared on a discontinuous Dextran gradient. No H+ efflux was detected on the addition of sucrose to energized vesicles. Therefore a H+/sucrose antiport may not be the mechanism of sucrose uptake at the tomato fruit tonoplast. Similar results were obtained with glucose, fructose and sorbitol. The lack of ATP (or PP1) stimulation of [14C]-sucrose uptake also suggested that an antiport was not involved. Initial uptake rates of radiolabelled glucose and fructose were almost double that for sucrose. The inhibition of hexose uptake by p-chloromercuribenzene sulphonate (PCMBS) implicated the involvement of a carrier. Therefore storage of hexose in the tomato fruit vacuole and maintenance of a downhill sucrose concentration gradient into sink cells is likely to be regulated by the activity of sucrose metabolizing enzymes, rather than by energy-requiring uptake mechanisms at the tonoplast.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1399-3054.1995.tb00945.x
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  • 7
    Electronic Resource
    Electronic Resource
    Apoptosis in nasopharyngeal carcinoma as related to histopathological characteristics and clinical stage (1998)
    Oxford, U.K. and Cambridge, USA : Blackwell Science Ltd
    Histopathology 33 (1998), S. 0 
    Details
    ISSN: 1365-2559
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: We investigated the significance of apoptosis, using the terminal deoxynucleotidyl transferase mediated dUTP-digoxigenin nick end-labelling method, in nasopharyngeal carcinoma biopsy samples.〈section xml:id="abs1-2"〉〈title type="main"〉Methods and resultsThe apoptotic index (AI) in 50 nasopharyngeal carcinomas was compared with various histopathological features and clinical stage. Also, the AI was correlated with p53, bcl-2 and Ki67 expression by immunohistochemistry. In histopathological studies, the AI was significantly higher in mixed cellular type (MC) than in keratizing squamous cell type (KS) and spindle cell type (SC) (P 〈 0.001) which worsens prognosis. In tumour stage analyses, AI was higher in early stage (stage 2 and 3) than in high stage (stage 4). In addition, there was a significant correlation between the AI and p53 expression (P 〈 0.001) but not with proliferative activity (P = 0.15). In NPC containing p53 protein positive tumour cells, there was a significantly higher apoptotic rate.〈section xml:id="abs1-3"〉〈title type="main"〉ConclusionsThese findings indicate that apoptosis is related to type and stage of nasopharyngeal carcinoma. They also confirm the role of p53 in regulating tumour apoptosis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2559.1998.00470.x
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  • 8
    Electronic Resource
    Electronic Resource
    Vaginal opacification during defecography: utility of placing a folded gauze square at the introitus (1999)
    Springer
    Abdominal imaging 24 (1999), S. 562-564 
    Details
    ISSN: 1432-0509
    Keywords: Key words: Bladder, abnormalities—Defecography—Gastrointestinal tract, radiography—Intestines, abnormalities—Rectum, abnormalities—Vagina.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We evaluated the value of placement of a folded gauze square into the urogenital introitus to improve vaginal opacification in 90 patients who underwent defecography. Of the 50 patients who retained the gauze in the introitus, 96% demonstrated excellent or good vaginal opacification. By contrast, only 75% of the 40 patients who lost the gauze during the study were able to achieve the same level of opacification. This difference was shown to be statistically significant (p 〈 0.002), suggesting that placement of a folded gauze square in the introitus limits loss of contrast from the vagina, which improves vaginal opacification.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002619900563
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  • 9
    Electronic Resource
    Electronic Resource
    Incidence of NIDDM and the effects of gender, obesity and hyperinsulinaemia in Taiwan (1997)
    Springer
    Diabetologia 40 (1997), S. 1431-1438 
    Details
    ISSN: 1432-0428
    Keywords: Keywords Non-insulin-dependent diabetes mellitus ; incidence ; risk factors ; anthropometry ; obesity ; insulin-blood ; Taiwan-epidemiology.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Our aim is to determine non-insulin-dependent diabetes mellitus (NIDDM) incidence in Taiwan and examine its relation to obesity and hyperinsulinaemia in Chinese men and women. A total of 995 men and 1195 women aged 35–74 years free from diabetes in two townships in Taiwan were followed up with a second examination. At baseline general and metabolic data were recorded, and detailed anthropometric parameters and plasma glucose and insulin were assessed. World Health Organisation (WHO) criteria of fasting glucose 7.8 mmol/l or greater was utilized for defining diabetes. The age-standardized incidence rate based on the United States population in 1970 was 9.3/1000 (CI 5.8–12.8) in men and 9.3/1000 (CI 6.2–12.4) in women and the based on the WHO population in 1976 was 8.9/1000 (CI .5–12.3) in men and 8.9/1000 (CI 5.9–11.9) in women for the Chinese who had a mean BMI slightly greater than 24 (kg/m2). The predictability of the plasma glucose level was greater than that of the insulin level and the obesity indices. NIDDM incidence increased approximately threefold with each 0.67 mmol/l increase in plasma glucose level in men and women. The present study demonstrated the essential relationship of not only BMI but also central obesity indices (such as subscapular and waist circumference) to the incidence of NIDDM among men and women and a stronger relationship between NIDDM incidence and obesity in women than in men. The predictive effects of obesity indices and fasting plasma insulin values on NIDDM risk were independent of each other in men. Obesity and hyperinsulinaemia each without the presence of the other can lead to an increased risk of NIDDM. In women the NIDDM incidence increased more than additively in those with both obesity and hyperinsulinaemia compared to those with single obesity or hyperinsulinaemia. A slightly higher incidence of NIDDM in Taiwan than in western countries was found. The importance of obesity is indicated for predicting NIDDM in the community. Hyperinsulinaemia was found to play a significant role in predicting NIDDM incidence independent of obesity in men and synergistically with obesity in women. [Diabetologia (1997) 40: 1431–1438]
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001250050846
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  • 10
    Electronic Resource
    Electronic Resource
    Luminescence centers in porous silicon (1995)
    Springer
    Applied physics 60 (1995), S. 601-606 
    Details
    ISSN: 1432-0630
    Keywords: PACS: 82.40.Tc; 81.40
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract.  Photoluminescence studies on porous silicon show that there are luminescence centers present in the surface states. By taking photoluminescence spectra of porous silicon with respect to temperature, a distinct peak can be observed in the temperature range 100–150 K. Both linear and nonlinear relationships were observed between excitation laser power and the photoluminescence intensity within this temperature range. In addition, there was a tendency for the photoluminescence peak to red shift at low temperature as well as at low excitation power. This is interpreted as indicating that the lower energy transition becomes dominant at low temperature and excitation power. The presence of these luminescence centers can be explained in terms of porous silicon as a mixture of silicon clusters and wires in which quantum confinement along with surface passivation would cause a mixing of Γ and X band structure between the surface states and the bulk. This mixing would allow the formation of luminescence centers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01538535
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