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101.
Here, we investigated the biological effects of arachidonic acid (AA) in human cumulus granulosa cells (CGCs) after exposure to ASA. Cells were isolated from the follicular fluid and incubated with 0.5 mM acetylsalicylic acid (ASA) and 50 µM AA. Cell viability was analyzed by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay. E2 and P4 levels were measured by chemiluminescence assay. Expression of genes including CYP19A1, FACN, and SCD1 was measured by real‐time polymerase chain reaction assay. Oxidative status was analyzed by monitoring glutathione peroxidase activity. The fatty acid profile was analyzed by the gas chromatography technique. Enzyme‐linked immunosorbent assay was used to measure prostaglandin E2 (PGE2) in CGCs after exposure to ASA and AA. Protein levels of the estrogen receptor were studied by immunofluorescence staining. Ultrastructural changes were evaluated by transmission electron microscopy imaging. ASA treatment reduced E2 production, Cyp19a1 expression, glutathione peroxidase (GPx) activity, and estradiol receptor expression in CGCs. The addition of AA prevented the ASA‐induced E2 reduction (p < .05) and expression of Cyp19a1. Moreover, AA increased the antioxidant capacity of CGCs exposed to ASA by promoting GPx activity (p < .05). AA increased monounsaturated fatty acid/saturated fatty acid ratio compared with the ASA group (p < .05). AA supplementation triggered the synthesis and secretion of PGE2 in ASA‐treated CGCS (p < .05). Cytoplasmic vacuolation observed in the ASA group and treatment with AA intensified vacuolation rate. The expression of the estrogen receptor was increased after AA supplementation. Data demonstrated that AA decreased the detrimental effects of ASA on human CGCs after 72 hr.  相似文献   
102.
p73, a member of the p53 tumor suppressor family, is involved in neurogenesis, sensory pathways, immunity, inflammation, and tumorigenesis. How p73 is able to participate in such a broad spectrum of different biological processes is still largely unknown. Here, we report a novel role of p73 in regulating lipid metabolism by direct transactivation of the promoter of autophagy-related protein 5 (ATG5), a gene whose product is required for autophagosome formation. Following nutrient deprivation, the livers of p73-deficient mice demonstrate a massive accumulation of lipid droplets, together with a low level of autophagy, suggesting that triglyceride hydrolysis into fatty acids is blocked owing to deficient autophagy (macrolipophagy). Compared with wild-type mice, mice functionally deficient in all the p73 isoforms exhibit decreased ATG5 expression and lower levels of autophagy in multiple organs. We further show that the TAp73α is the critical p73 isoform responsible for inducing ATG5 expression in a p53-independent manner and demonstrate that ATG5 gene transfer can correct autophagy and macrolipophagy defects in p73-deficient hepatocytes. These data strongly suggest that the p73–ATG5 axis represents a novel, key pathway for regulating lipid metabolism through autophagy. The identification of p73 as a major regulator of autophagy suggests that it may have an important role in preventing or delaying disease and aging by maintaining a homeostatic control.  相似文献   
103.
Based on investigations, there exist tight correlations between neurodegenerative diseases' incidence and progression and aberrant protein aggregreferates in nervous tissue. However, the pathology of these diseases is not well known, leading to an inability to find an appropriate therapeutic approach to delay occurrence or slow many neurodegenerative diseases' development. The accessibility of induced pluripotent stem cells (iPSCs) in mimicking the phenotypes of various late-onset neurodegenerative diseases presents a novel strategy for in vitro disease modeling. The iPSCs provide a valuable and well-identified resource to clarify neurodegenerative disease mechanisms, as well as prepare a promising human stem cell platform for drug screening. Undoubtedly, neurodegenerative disease modeling using iPSCs has established innovative opportunities for both mechanistic types of research and recognition of novel disease treatments. Most important, the iPSCs have been considered as a novel autologous cell origin for cell-based therapy of neurodegenerative diseases following differentiation to varied types of neural lineage cells (e.g. GABAergic neurons, dopamine neurons, cortical neurons, and motor neurons). In this review, we summarize iPSC-based disease modeling in neurodegenerative diseases including Alzheimer's disease, amyotrophic lateral sclerosis, Parkinson's disease, and Huntington's disease. Moreover, we discuss the efficacy of cell-replacement therapies for neurodegenerative disease.  相似文献   
104.
All-cellulose nanocomposite was directly fabricated using nanowelding of cellulose microfibers as a starting material, in 1-butyl-3-methylimidazolium chloride (BMIMCl) as a solvent, for the first time. The average diameter of the reinforcing component (undissolved nanofibrils) in the nanocomposite made directly from cellulose microfibers (NC-microfiber) was 53 ± 16 nm. Owing to its high mechanical properties (tensile strength of 208 MPa and Young's modulus of 20 GPa), high transparency (76% at a wavelength of 800 nm), and complete barrier to air and biodegradability, the NC-microfiber is regarded as a high multiperformance material. The NC-microfiber made directly from cellulose microfibers showed similar macro-, micro-, and nanostructures and the same properties as those made from solvent-based welding of ground cellulose nanofibers (NC-nanofiber). Omitting the step of cellulose nanofiber production makes the direct production of all-cellulose nanocomposite from cellulose microfibers easier, shorter, and cheaper than using cellulose nanofibers as starting material. The direct nanowelding of macro/micrometer-sized materials is theorized to be a fundamental approach for making nanocomposites.  相似文献   
105.
In vivo imaging and quantification of amyloid-β plaque (Aβ) burden in small-animal models of Alzheimer's disease (AD) is a valuable tool for translational research such as developing specific imaging markers and monitoring new therapy approaches. Methodological constraints such as image resolution of positron emission tomography (PET) and lack of suitable AD models have limited the feasibility of PET in mice. In this study, we evaluated a feasible protocol for PET imaging of Aβ in mouse brain with [(11)C]PiB and specific activities commonly used in human studies. In vivo mouse brain MRI for anatomical reference was acquired with a clinical 1.5 T system. A recently characterized APP/PS1 mouse was employed to measure Aβ at different disease stages in homozygous and hemizygous animals. We performed multi-modal cross-validations for the PET results with ex vivo and in vitro methodologies, including regional brain biodistribution, multi-label digital autoradiography, protein quantification with ELISA, fluorescence microscopy, semi-automated histological quantification and radioligand binding assays. Specific [(11)C]PiB uptake in individual brain regions with Aβ deposition was demonstrated and validated in all animals of the study cohort including homozygous AD animals as young as nine months. Corresponding to the extent of Aβ pathology, old homozygous AD animals (21 months) showed the highest uptake followed by old hemizygous (23 months) and young homozygous mice (9 months). In all AD age groups the cerebellum was shown to be suitable as an intracerebral reference region. PET results were cross-validated and consistent with all applied ex vivo and in vitro methodologies. The results confirm that the experimental setup for non-invasive [(11)C]PiB imaging of Aβ in the APP/PS1 mice provides a feasible, reproducible and robust protocol for small-animal Aβ imaging. It allows longitudinal imaging studies with follow-up periods of approximately one and a half years and provides a foundation for translational Alzheimer neuroimaging in transgenic mice.  相似文献   
106.
107.
Complex molecular changes that occur during prostate cancer (PCa) progression have been described recently. Whole genome sequencing of primary PCa samples has identified recurrent gene deletions and rearrangements in PCa. Specifically, these molecular events disrupt the gene loci of phosphatase and tensin homolog (PTEN) and membrane-associated guanylate kinase inverted-2 (MAGI2). In the present study, we analyzed the expression profile of MAGI2 gene in a cohort of clinical PCa (n = 45) and benign prostatic hyperplasia (BPH) samples (n = 36) as well as three PCa cell lines. We also studied the expression of PCa-related genes, including PTEN, NKX3.1, SPINK1, DD3, AMACR, ERG, and TMPRSS2-ERG fusion in the same samples. The expression of MAGI2 mRNA was significantly down-regulated in PC3, LNCaP and DU-145 PCa cell lines (p = 0.000), and also in clinical tumor samples (Relative expression = 0.307, p = 0.002, [95 % CI 0.002–12.08]). The expression of PTEN, NKX3.1, SPINK1, DD3, and AMACR genes was significantly deregulated in prostate tumor samples (p range 0.000–0.044). A significant correlation was observed between MAGI2 and NKX3.1 expression in tumor samples (p = 0.006). Furthermore, the inclusion of MAGI2 in the gene panel improved the accuracy for discrimination between PCa and BPH samples with the sensitivity and specificity of 0.88 [CI 0.76–0.95] and 0.83 [CI 0.68–0.92], respectively. The data presented here suggest that MAGI2 gene can be considered as a novel component of gene signatures for the detection of PCa.  相似文献   
108.
The intestine is the largest mucosal organ of the body and also the first line immune homeostasis. Inflammatory bowel disease or IBD is divided into ulcerative colitis and Crohn''s disease. One of the problems that can occur with UC is dietary allergy to some foods. This study aimed to evaluated the dairy allergy among patients with ulcerative colitis. This study is a Case - control study, that studied 72 patients with Ulcerative Colitis, after recording history of the disease, colonoscopy and confirmed by biopsy and 72 person without history of colitis. In this study, in order to investigate of food allergy, used of the EUROMMUM kit with an international code number DP3420-1601-11E. We used chi-square and Monte Carlo method for analysis of data. Among UC patients, 30.6% mild, 52.8% moderate and 16.6% of cases were in sever stage. 9.7% of them reported a history of abdominal surgery due to disease. According to the chi-square and Monte Carlo methods, dairy allergy (including: cow milk, cow milk UHT and casein) in UC group was significant (P=0.00). This study indicated that there is significant relationship between UC and cow milk, cow milk UHT and casein. UC patients who are allergic to dairy products and the use of dairy products can increase the severity of UC.  相似文献   
109.
110.
Precursor B-cell acute lymphoblastic leukemia (B-ALL) is the most prevalent pediatric cancer. DNA methylation and changes in the microRNAs (miRNAs) expression are known to be important causes of B-ALL. Decitabine as a DNA methyltransferase inhibitor agent is able to induce hypomethylation in several tumor suppressor genes. Much evidence has proven BTG2, PPP1CA, and PTEN act as tumor suppressor genes in many malignancies. In this case control study, the messenger RNA (mRNA) expression of PPP1CA, BTG2, and PTEN genes using quantitative real-time polymerase chain reaction (rRT-PCR) in Nalm6 cell line and five patients suffer from ALL with mean age 5.6 years were determined in compare with seven normal healthy donors age and sex matched. qRT-PCR analysis revealed that the expression levels of PPP1CA, BTG2, and PTEN genes were significantly decreased in Nalm6 ([FC] = 0.46, [FC] = 0.046, [FC] = 0.54) and according to the Methylation-specific PCR (MSP) analysis, these genes were hypermethylated in Nalm6. In next step, the effects of decitabine treatment on the methylation and expression of these genes in association with changes in miR-125b, miR-17, and miR-181b expression levels were evaluated in optimal concentration 2.5 µM of decitabine. Our data showed that decitabine is able to restore the expression levels of aforementioned genes and downregulate expression levels of oncomiRs; including miR-125b, miR-17, and miR-181b in Nalm6 cell line. Therefore, it seems that decitabine can be used as a potential drug for the first line treatment of patients with B-ALL, but further in vivo investigation is necessary.  相似文献   
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