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51.
Lifestyle‐determining extrachromosomal replicon pAMV1 and its contribution to the carbon metabolism of the methylotrophic bacterium Paracoccus aminovorans JCM 7685 下载免费PDF全文
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Nowak M Wielkoszyński T Marek B Kos-Kudła B Swietochowska E Siemińska L Kajdaniuk D Głogowska-Szelag J Nowak K 《Endokrynologia Polska》2008,59(1):2-5
INTRODUCTION: The aim of this study was to evaluate the blood concentration of hepatocyte growth factor (HGF) in patients at various stages of retinopathy. We hypothesised that the high level of HGF found in diabetic patients may be an important marker of retinopathy progression and that HGF level may be an index of the risk of proliferative retinopathy. MATERIAL AND METHODS: The participants in the study were 76 patients with type 1 diabetes mellitus. Of these, 35 patients were without retinopathy and formed Group 1. Of the remaining 41 patients with retinopathy, 20 patients had non-proliferative diabetic retinopathy (NPDR) and formed Group 2, while 21 patients had proliferative diabetic retinopathy (PDR) and formed Group 3. We evaluated the concentration of HGF In the peripheral blood by an enzyme-linked immunosorbent assay. RESULTS: Mean serum concentrations of HGF in the control group were significantly lower than in the type 1 diabetic patients. We found a significant increase in HGF serum concentrations in diabetic patients with PDR compared with the control group. Mean serum HGF concentrations were significantly higher in diabetic subjects with PDR than in diabetic patients without retinopathy. CONCLUSION: HGF concentration is increased in patients with type 1 diabetes mellitus with proliferative retinopathy, and concentrations increase with the progression of retinopathy, suggesting that HGF plays a role in the pathogenesis of proliferative diabetic retinopathy. 相似文献
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Ewa Rębacz-Maron Irena Baranowska-Bosiacka Izabela Gutowska Natalia Krzywania Dariusz Chlubek 《Biological trace element research》2013,156(1-3):91-95
The present study aimed at analysing the content of fluorine (F), calcium (Ca) and magnesium (Mg) in the hair of young male students (n?=?52) of a secondary school in Mafinga in Tanzania (Africa) who participated in anthropological examinations. Ca and Mg concentrations were determined using atomic absorption spectrophotometer while F levels using a potentiometric method. F in the hair of boys from older group (≥16 years old; n?=?24) was significantly higher than in the younger group (<16 years old; n?=?28) versus Ca and Mg levels. High carbohydrate diet was predominant—mainly based on corn or bean and meat served once a week, with few fruit and raw vegetables. Collective catering in the dormitory reflected habits and culinary preferences at home. The lack of balanced diet, with majority of the nutritional energy supplied by easily accessible and cheap carbohydrates, was reflected in dietary deficiencies, characterised, among others, by visible skin conditions and tooth decay. 相似文献
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Dariusz Pawlak Tomasz Domaniewski Beata Sieklucka Magdalena Jakuc Krystyna Pawlak 《生物化学与生物物理学报:疾病的分子基础》2019,1865(11):165528
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Stepniak D Spaenij-Dekking L Mitea C Moester M de Ru A Baak-Pablo R van Veelen P Edens L Koning F 《American journal of physiology. Gastrointestinal and liver physiology》2006,291(4):G621-G629
Celiac disease is a T cell-driven intolerance to wheat gluten. The gluten-derived T cell epitopes are proline-rich and thereby highly resistant to proteolytic degradation within the gastrointestinal tract. Oral supplementation with prolyl oligopeptidases has therefore been proposed as a potential therapeutic approach. The enzymes studied, however, have limitations as they are irreversibly inactivated by pepsin and acidic pH, both present in the stomach. As a consequence, these enzymes will fail to degrade gluten before it reaches the small intestine, the site where gluten induces inflammatory T cell responses that lead to celiac disease. We have now determined the usefulness of a newly identified prolyl endoprotease from Aspergillus niger for this purpose. Gluten and its peptic/tryptic digest were treated with prolyl endoprotease, and the destruction of the T cell epitopes was tested using mass spectrometry, T cell proliferation assays, ELISA, reverse-phase HPLC, SDS-PAGE, and Western blotting. We observed that the A. niger prolyl endoprotease works optimally at 4-5 pH, remains stable at 2 pH, and is completely resistant to digestion with pepsin. Moreover, the A. niger-derived enzyme efficiently degraded all tested T cell stimulatory peptides as well as intact gluten molecules. On average, the endoprotease from A. niger degraded gluten peptides 60 times faster than a prolyl oligopeptidase. Together these results indicate that the enzyme from A. niger efficiently degrades gluten proteins. Future studies are required to determine if the prolyl endoprotease can be used as an oral supplement to reduce gluten intake in patients. 相似文献
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Cryopreservation is widely applied to many economically important species excluding chimera plants which are problematic for long-term conservation. Their storage problems can be circumvented only by cryopreserving meristems. This study looked at the morphogenetic response of shoot tips of periclinal chimera chrysanthemum ‘Lady Orange’ and ‘Lady Salmon’, as well as the solid mutant ‘Richmond’, that were cryopreserved by encapsulation-dehydration technique. By applying 10 µM ABA in the preculture medium followed by 4-day-long dehydration treatment, the explant survival reached up to 67%. Besides the stimulation of typical single shoot recovery, cryopreservation led to direct or indirect multiple shoot formation, shoot malformation, as well as inhibited their spontaneous rooting. Microscopic analysis revealed three types of structural damages of shoot tips which can correspond with their morphogenetic response in recovery culture. No influence of cryostorage on the acclimatisation efficiency of the recovered chrysanthemums was observed. 相似文献
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Waszkiewicz N Szajda SD Zalewska A Szulc A Kępka A Minarowska A Wojewódzka-Żelezniakowicz M Konarzewska B Chojnowska S Ladny JR Zwierz K 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2012,50(1):1-11
The relationship between alcohol consumption and glycoconjugate metabolism is complex and multidimensional. This review summarizes the advances in basic and clinical research on the molecular and cellular events involved in the metabolic effects of alcohol on glycoconjugates (glycoproteins, glycolipids, and proteoglycans). We summarize the action of ethanol, acetaldehyde, reactive oxygen species (ROS), nonoxidative metabolite of alcohol--fatty acid ethyl esters (FAEEs), and the ethanol-water competition mechanism, on glycoconjugate biosynthesis, modification, transport and secretion, as well as on elimination and catabolism processes. As the majority of changes in the cellular metabolism of glycoconjugates are generally ascribed to alterations in synthesis, transport, glycosylation and secretion, the degradation and elimination processes, of which the former occurs also in extracellular matrix, seem to be underappreciated. The pathomechanisms are additionally complicated by the fact that the effect of alcohol intoxication on the glycoconjugate metabolism depends not only on the duration of ethanol exposure, but also demonstrates dose- and regional-sensitivity. Further research is needed to bridge the gap in transdisciplinary research and enhance our understanding of alcohol- and glycoconjugate-related diseases. 相似文献