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排序方式: 共有508条查询结果,搜索用时 171 毫秒
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Maryam Vahdat-Lasemi Sara Hosseini Vahid Jajarmi Bahram Kazemi Mohammad Salehi 《Journal of cellular physiology》2019,234(8):13858-13866
miR-224 is associated with polycystic ovary syndrome (PCOS) that is an epidemic in reproductive age women. Most studies of miR-224 have focused on in vitro analyses, whereas the in vivo effects are not widely understood. In this study, we have conducted in silico analysis and found two potential miR-224 target genes, Ptx3 and Smad4 that have roles in folliculogenesis. Because patients with PCOS have decreased numbers of follicular cells related to cell apoptosis, we also investigated two apoptotic genes, Bax and Bcl2. We used the intraovarian injection method to deliver miR-224 into a mouse model. Histological examination of the ovaries was done by fluorescent microscope. Fertilization, cleavage, and developmental competence rates were counted under a stereomicroscope and compared between the studied groups. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis of miR-224 was conducted to determine the levels of the studied genes in the oocytes, cumulus cells, and blastocysts. The numbers of oocytes and fertilization rate indicated a higher apoptosis index ( p < 0.05) and increased numbers of degenerated embryos with irregular blastomeres and fragmented cytoplasm in the experimental group. RT-PCR results indicated a significant increase in miR-224 levels in the manipulated group. Of the four analyzed genes, Ptx3, Smad4, and Bcl2 had decreased levels in the transfected group, with increased Bax expression ( p < 0.05). This data showed that miR-224 negatively affected ovulation in the mouse model by decreasing Ptx3 and Smad4 expressions. The changes in Bcl2 and Bax expression levels, as apoptosis biomarkers, showed that apoptosis was a secondary outcome of the effect of miR-224. 相似文献
23.
Mohammad Hassanzadeh Saber Shahrouz Baradaran Noveiri Mohammad Pourkazemi Mahtab Yarmohammadi Jalil Jalilpour Mohammadreza Nowruz Fashkhami Bahram Falahatkar 《Zeitschrift fur angewandte Ichthyologie》2019,35(4):843-849
In sturgeons, the induction of gynogenesis and sex reversal could be important for potential production of neomale sturgeon and all‐female progeny for caviar production. The aim of this study was sex reversal of ship sturgeon (Acipenser nudiventris Lovetsky, 1828) gynogen into male sex. Five‐month‐old gynogens were sex reversed into male by including 17α‐methyl testosterone in their food for 7 months. Three treatments were considered as follows: (a) without treated (gynogen control), (b) 10 mg MT/kg diet, and (c) 50 mg MT/kg diet. All treatments (60 individuals) were sampled both the 30 and 36 months old and their sex was determined using classical histology method of gonad. The sex ratio of the progenies in the gynogen control were 73.3% female and 26.7% male. In treatment of 10 mg MT/kg feed, 18 specimens were studied that half of them (50%) showed pseudo‐testicular structure in the female gonad. That is 50% of the specimens were intersex, 27.7% were male and 22.3% were female. All of the fish fed by 50 mg MT/kg feed had been sex reversed to male. Sexual maturation of these fish had been recognized in stage III at 36 months old. In conclusion, 50 mg MT/kg feed found as effective dose for successful sex reversal in gynogenetic ship sturgeon. 相似文献
24.
Bahram Falahatkar Iraj Efatpanah Bahman Meknatkhah 《Zeitschrift fur angewandte Ichthyologie》2019,35(1):283-288
This study compared the influence of feeding methods on growth parameters of young‐of‐year Beluga sturgeon Huso huso in a 6‐week trial. Fish with an average weight 150.3 ± 0.8 g (±SE) were stocked into nine circular concrete tanks (30 fish per tank) in an open circular system with water temperature of 18.9°C. All fish were fed by three different feeding methods: (a) hand‐fed (HF), (b) continuously available (automated feeder; AF), (c) half of daily feed provided by hand, and another half by automated feeder (combined feeding). For the hand‐feeding method, fish were fed at 09:00, 14:00, 19:00, and 24:00. The entire automatic feeding groups were fed with the same amount of feed. The mean final body weight was the highest in fish fed by AF compared to fish fed by HF. Body weight increase, condition factor, specific growth rate, and feed conversion ratio did not differ among the feeding groups. Fish fed by AF revealed higher swimming activity than the HF group. No significant changes were found in hematocrit, glucose and total protein concentrations among treatments. The results showed less dependence of growth and physiology of Beluga sturgeon on feeding method, but automated‐feeding was shown to be suitable for sturgeon rearing because of further low labour costs in rearing systems. 相似文献
25.
Somaye Shahraki Fereshteh Shiri Mostafa Heidari Majd Somaye Dahmardeh 《Journal of biomolecular structure & dynamics》2019,37(8):2072-2085
In this study, a new lanthanum (III)-amino acid complex utilizing cysteine has been synthesized and characterized. The anticancer activities of the prepared La(III) complex against MCF-7 cell lines were studied. Results of MTT assay showed that at all three incubation times, the cytotoxic effect of prepared La(III) complex on MCF-7 breast cancer cell lines displays a time- and dose-dependent inhibitory effects. The interactions of the La(III) complex with two whey proteins (bovine serum albumin, BSA, and Bovine β-lactoglobulin, βLG) have been explored by using spectroscopic and molecular dicking methods. The obtained results indicated that La(III) complex strongly quenched the fluorescence of two carrier proteins in static quenching mode and also, BSA hah stronger binding affinity toward studied complex than βLG whit binding constant values of KBSA-La?Complex?~?0.11?×?104 M?1 and KβLG-La?Complex?~?0.63?×?103 M?1 at 300 K. The thermodynamic parameters revealed the contribution of hydrogen bond and Vander Waals interactions in both systems. The distances of the La(III) complex whit whey proteins were calculated using Förster energy transfer theory and proved existence of the energy transfer between two proteins and prepared La(III) complex with a high probability. FT-IR and UV–Vis absorption measurements indicated that the binding of the La(III) to BSA and βLG may induce conformational and micro-environmental changes of the proteins. The docking results indicate that the La(III) complex bind to residues located in the site II of BSA and second site of βLG.
Communicated by Ramaswamy H. Sarma 相似文献
26.
Laleh Heidari Sayyed Mohammad Hossein Ghaderian Hossein Vakili Tayyeb Ali Salmani 《Journal of cellular biochemistry》2019,120(8):12360-12368
Coronary artery disease (CAD) is a multifactorial chronic inflammatory disease, which is the most common form of heart disease. This is one of the main causes of death in the United States. Inflammation is one of the key drivers of atherosclerotic plaque development. Forkhead box protein O1 (FOXO1s) family and 5-lipoxygenase make an important contribution to atherosclerosis. The aim of this study was to investigate the methylation pattern and polymorphism analysis of FOXO1 and arachidonate 5-lipoxygenase (ALOX5) promoter genes. We studied 50 patients with CAD and 50 age- and sex-matched healthy controls by high resolution melt technique. Overall, we found significant differences between patients and controls in terms of the promoter methylation of ALOX5 (P > 0.05). But there was no significant difference in FOXO1 promoter methylation between patient and controls. Single nucleotide polymorphisms genotyping of rs12762303 and rs2297627, in ALOX5 and FOXO1 genes were demonstrated a significant correlation between mutant allele and the risk of CAD, respectively. Furthermore, there were significant associations between CT + CC genotype and ALOX5 expression. Our findings demonstrated functional effects of single nucleotide polymorphisms (SNPs) and DNA methylation in ALOX5 on mentioned genes expression and they resulted in CAD progression. 相似文献
27.
28.
Hamid Hadi-Alijanvand Elizabeth A. Proctor Bahram Goliaei Nikolay V. Dokholyan Ali A. Moosavi-Movahedi 《PloS one》2012,7(10)
Prolyl hydroxylase domain 2 containing protein (PHD2) is a key protein in regulation of angiogenesis and metastasis. In normoxic condition, PHD2 triggers the degradation of hypoxia-inducible factor 1 (HIF-1α) that induces the expression of hypoxia response genes. Therefore the correct function of PHD2 would inhibit angiogenesis and consequent metastasis of tumor cells in normoxic condition. PHD2 mutations were reported in some common cancers. However, high levels of HIF-1α protein were observed even in normoxic metastatic tumors with normal expression of wild type PHD2. PHD2 malfunctions due to protein misfolding may be the underlying reason of metastasis and invasion in such cases. In this study, we scrutinize the unfolding pathways of the PHD2 catalytic domain’s possible species and demonstrate the properties of their unfolding states by computational approaches. Our study introduces the possibility of aggregation disaster for the prominent species of PHD2 during its partial unfolding. This may justify PHD2 inability to regulate HIF-1α level in some normoxic tumor types. 相似文献
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30.
Uzgiris EE Cline H Moasser B Grimmond B Amaratunga M Smith JF Goddard G 《Biomacromolecules》2004,5(1):54-61
The structure of Gd-DTPA-polylysine, Gd-DOTA-polylysine, Gd-SCN-Bz-DOTA-polylysine, and Gd-DTPA-poly(glu:lys) was investigated with circular dichroism, gel permeation chromatography, low angle light scattering, and proton longitudinal relaxivity. Molecular modeling calculations were performed and predicted helical secondary structure for charged Gd-chelator residues, i.e., Gd-DTPA, when the DTPA conjugation levels reached 90% and higher. This helical secondary structure was observed with circular dichroism. The conformational transition from coiled to extended linear was observed also by gel permeation chromatography and by proton relaxivity measurements. The helical secondary structure was not observed when the chelator was changed to DOTA. The residue charge interactions were eliminated in this case since the Gd-DOTA complex had no net charge. For this construct, the gel permeation and relaxivity measurements indicated a coiled conformation. An extended linear conformation was regained when the chelator complex was changed to Gd-SCN-Bz-DOTA, which had a net negative charge. The functional aspects of these structures were investigated by MR imaging of an animal tumor model. The linear extended polymer constructs gave 10-fold higher tumor signals then the coiled-collapsed constructs, indicating a much higher degree of trans-endothelial transport in the tumors. 相似文献