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91.
Type I galactosemia is an inborn error resulting from mutations on both alleles of the GALT gene, which leads to the absence or deficiency of galactose-1-phosphate uridyltranseferase (GALT), the second of three enzymes catalyzing the conversion of galactose into glucose. On the basis of residual GALT activity, Type I galactosemia is classified into severe “Classical” and mild “Duarte” phenotypes. Classical galactosemia is frequently associated with S135L, Q188R and K285N mutations in the GALT gene. The functionally neutral N314D variation in the GALT gene is associated with Duarte galactosemia and is widespread among various worldwide populations. The present study aimed at detecting S135L, Q188R and K285N mutations and the N314D variant in the GALT gene by PCR using amplification refractory mutation system (ARMS). ARMS assays were established using standard DNA samples and were used for 8 galactosemia patients and 190 unrelated normal subjects all of Pakistani origin. S135L and K285N mutations were present neither in galactosemia patients nor in normal subjects. Only one galactosemia patient carried Q188R mutation that was in homozygous state. However, the N314D variant was frequently found both in affected (7 out of 16 alleles) and normal subjects (55 out of 380 alleles). This finding indicates that Duarte allele D314 might be far more common in Pakistani population than in European and North American ones.  相似文献   
92.
93.
Wetlands Ecology and Management - Bangladesh has the single largest tract of naturally growing mangrove forest as well as the world’s largest manmade mangrove forest on newly accreted land in...  相似文献   
94.
Recent advances in wound healing have made cell therapy a potential approach for the treatment of various types of skin defects such as trauma, burns, scars and diabetic leg ulcers. Cultured keratinocytes have been applied to burn patients since 1981. Patients with acute and chronic wounds can be treated with autologous/allograft cultured keratinocytes. There are various methods for cultivation of epidermal keratinocytes used in cell therapy. One of the important properties of an efficient cell therapy is the preservation of epidermal stem cells. Mesenchymal Stem Cells (MSCs) are major regulatory cells involved in the acceleration of wound healing via induction of cell proliferation, angiogenesis and stimulating the release of paracrine signaling molecules. Considering the beneficial effects of MSCs on wound healing, the main aim of the present study is investigating paracrine effects of Adipose-derived Mesenchymal Stem Cell (Ad-MSCs) on cultivation of keratinocytes with focusing on preservation of stem cells and their differentiation process. We further introduced a new approach for culturing isolated keratinocytes in vitro in order to generate epidermal keratinocyte sheets without using a feeder layer. To do so, Ad-MSC conditioned medium was applied as an alternative to commercial media for keratinocyte cultivation. In this study, the expression of several stem/progenitor cell (P63, K19 and K14) and differentition (K10, IVL and FLG) markers was examined using real time PCR on days 7, 14 and 21 of culture in keratinocytes in Ad-MSC conditioned medium. P63 and α6 integrin expression was also evaluated via flow cytometry. The results were compared with control group including keratinocytes cultured in EpiLife medium and our data indicated that this Ad-MSC conditioned medium is a good alternative for keratinocyte cultivation and producing epidermal sheets for therapeutic and clinical purposes. The reasons are the expression of stem cell and differentiation markers and overcoming the requirement for feeder layer which leads to a xenograft-free transplantation. Besides, this approach has low cost and is easier to perform. However, more in vitro and in vivo experiments as well as safety evaluation required before clinical applications.  相似文献   
95.
96.
Zinc oxide (ZnO) nanostructures have been commonly studied for electronic purposes due to their unique piezoelectric and catalytic properties; however, recently, they have been also exploited for biomedical applications. The purpose of this study was to fabricate ZnO-doped poly(urethane) (PU) nanocomposite via one-step electrospinning technique. The utilized nanocomposite was prepared by using colloidal gel composed of ZnO and PU, and the obtained mats were vacuum dried at 60 °C overnight. The physicochemical characterization of as-spun composite nanofibers was carried out by X-ray diffraction pattern, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, electron probe microanalysis, and transmission electron microscopy, whereas the thermal behavior was analyzed by thermogravimetric analysis. The viability, attachment, and proliferation of NIH 3T3 mouse fibroblast cells on the ZnO/PU composite nanofibers were analyzed by in vitro cell compatibility test. The morphological features of the cells attached on nanofibers were examined by Bio-SEM. We conclude that the electrospun nanofibrous scaffolds with unique spider nets had good biocompatibility. Cytotoxicity experiments indicated that the mouse fibroblasts could attach to the nanocomposite after being cultured. Thus, the current work demonstrates that the as-synthesized ZnO/PU hybrid nanofibers represent a promising biomaterial to be exploited for various tissue engineering applications.  相似文献   
97.
Ethanol feeding to rats daily for 40 days induces the secretion of surfactant-like-particles in intestine. The isolated lipoprotein particles were enriched with alkaline phosphatase activity and had high phosphatidylcholine content. There was no difference in disaccharidases activities associated with the particles from control and ethanol fed rats. These results suggest that ethanol induced surfactant-like-particles in rat intestine.  相似文献   
98.
A new series of steroidal dihydrocarbothioic acid amido pyrazole analogues were synthesized, and after characterization, evaluation for cytotoxicity, comet assay and western blotting was carried out. The synthesis of these analogues is convenient and involves two steps, i.e. aldol condensation as first step followed by nucleophilic addition of thiosemicarbazide across α, β-unsaturated carbonyl as a later step. Quantitative yields of more than 80 % are obtained in both the steps. After characterization by IR, 1H NMR, 13C NMR, MS and analytical data, all the compounds of both series were tested for cytotoxic activity against a panel of different human cancer cell lines by MTT assay, during which compound 3e, 3f, 4e, 4f and 4h are very potent especially against HepG2 and MCF-7 cancer cell lines. Cell cycle analysis depicted the cell death in S-phase while as annexin V-FITC/PI analysis showed that compounds effectively induce apoptosis. Apoptotic degradation of DNA of MCF-7 cells in the presence of different steroidal derivatives was analysed by agarose gel electrophoresis and visualized by ethidium bromide staining (comet assay). In western blotting analysis, the relative expressions of relevant apoptotic markers depicted an apoptosis by steroidal dihydropyrazole in MCF-7 cancer cells.  相似文献   
99.
Recent studies have established the interaction between APOA2 −256T>C polymorphism and dietary saturated fatty acids intake in relation to obesity on healthy individuals. In the current study, we investigate the effects of this interaction on anthropometric variables and serum levels of leptin and ghrelin in patients with type 2 diabetes. In this cross-sectional study, 737 patients with type 2 diabetes mellitus (290 males and 447 females) were recruited from diabetes clinics in Tehran. The usual dietary intake of all participants during the last year was obtained by validated semiquantitative food frequency questionnaire. APOA2 genotyping was performed by real-time PCR on genomic DNA. No significant relation was obtained by univariate analysis between anthropometric variables and APOA2 genotypes. However, after adjusting for age, gender, physical activity and total energy intake, we identified a significant interaction between APOA2-saturated fatty acids intake and body mass index (BMI). After adjusting for potential confounders, serum levels of ghrelin in CC genotype patients were significantly higher than T allele carriers (p = 0.03), whereas the case with leptin did not reveal a significant difference. The result of this study confirmed the interaction between APOA2 −256T>C polymorphism and SFAs intake with BMI in type 2 diabetic patients. In fact, homozygous patients for the C allele with high saturated fatty acids intake had higher BMI. The APOA2 −256T>C polymorphism was associated with elevated levels of serum ghrelin.  相似文献   
100.

Background

Zingiber zerumbet Smith is a perennial herb, broadly distributed in many tropical areas. In Malaysia, it’s locally known among the Malay people as “lempoyang” and its rhizomes, particularly, is widely used in traditional medicine for the treatment of peptic ulcer disease beyond other gastric disorders.

Aim of the study

The aim of the current study is to evaluate the gastroprotective effect of zerumbone, the main bioactive compound of Zingiber zerumbet rhizome, against ethanol-induced gastric ulcer model in rats.

Materials and Methods

Rats were pre-treated with zerumbone and subsequently exposed to acute gastric ulcer induced by absolute ethanol administration. Following treatment, gastric juice acidity, ulcer index, mucus content, histological analysis (HE and PAS), immunohistochemical localization for HSP-70, prostaglandin E2 synthesis (PGE2), non-protein sulfhydryl gastric content (NP-SH), reduced glutathione level (GSH), and malondialdehyde level (MDA) were evaluated in ethanol-induced ulcer in vivo. Ferric reducing antioxidant power assay (FRAP) and anti-H. pylori activity were investigated in vitro.

Results

The results showed that the intragastric administration of zerumbone protected the gastric mucosa from the aggressive effect of ethanol-induced gastric ulcer, coincided with reduced submucosal edema and leukocyte infiltration. This observed gastroprotective effect of zerumbone was accompanied with a significant (p <0.05) effect of the compound to restore the lowered NP-SH and GSH levels, and to reduce the elevated MDA level into the gastric homogenate. Moreover, the compound induced HSP-70 up-regulation into the gastric tissue. Furthermore, zerumbone significantly (p <0.05) enhanced mucus production, showed intense PAS stain and maintained PG content near to the normal level. The compound exhibited antisecretory activity and an interesting minimum inhibitory concentration (MIC) against H. pylori strain.

Conclusion

The results of the present study revealed that zerumbone promotes ulcer protection, which might be attributed to the maintenance of mucus integrity, antioxidant activity, and HSP-70 induction. Zerumbone also exhibited antibacterial action against H. pylori.  相似文献   
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