A Study on Expression and Tyrosine 705 phosphorylation of STAT3 in Focal Cerebral Ischemia-Reperfusion Rat Model and its Role in Neuronal Apoptosis

Purpose: To investigate the expression and tyrosine 705 phosphorylation of STAT3 in focal cerebral ischemia-reperfusion rat model and its role in neuronal apoptosis.Methods: Ischemia-reperfusion model was established by thread-occluded method. Tetrazolium red (TTC), H/E and Nissl staining were used to evaluate whether ischemia-reperfusion model was successfully established. TUNEL staining and immunohistochemistry were employed to monitor apoptosis-positive nerve cells as well as STAT3-, p-Tyr705-STAT3-, Bcl-2- and Fas-positive cells in ischemic penumbra (IP) and ischemic core (IC).Results: The results of TTC, HE and Nissl staining indicated that the ischemia reperfusion model was successfully established. After 3 h, ischemia followed by different reperfusion times, the STAT3-, p- Tyr705-STAT3-, Fas- and Bcl-2 positive cells counts and the apoptosis-positive nerve cells count were significantly (p < 0.05 or 0.01) increased to 27.20, 29.20, 15.90, 18.50, and 202.00 in IP and 19.50, 21.20, 12.50, 12.40, and 97.80 in IC, compared with the sham-operated group. As reperfusion times increased, cell counts did not decrease significantly relative to control group. Correlation analysis indicate that there was significant (p < 0.01) positive correlations among STAT3-, p-Tyr705 STAT3-, Fas- and Bcl-2-positive cells counts on the one hand, and apoptosis positive nerve cells count in IP and IC, on the other hand.Conclusion: Regulating expression and tyrosine 705 phosphorylation of STAT3 may be a new and effective strategy for treating cerebral infarction.Keywords: Ischemia-reperfusion, Neuronal apoptosis, STAT3, Phosphorylation, Cerebral infarctio

Study of RNA interference inhibiting rat ovarian androgen biosynthesis by depressing 17alpha-hydroxylase/17, 20-lyase activity in vivo

<p>Abstract</p> <p>Background</p> <p>17alpha-hydroxylase/17, 20-lyase encoded by CYP17 is the key enzyme in androgen biosynthesis pathway. Previous studies demonstrated the accentuation of the enzyme in patients with polycystic ovary syndrome (PCOS) was the most important mechanism of androgen excess. We chose CYP17 as the therapeutic target, trying to suppress the activity of 17alpha-hydroxylase/17, 20-lyase and inhibit androgen biosynthesis by silencing the expression of CYP17 in the rat ovary.</p> <p>Methods</p> <p>Three CYP17-targeting and one negative control oligonucleotides were designed and used in the present study. The silence efficiency of lentivirus shRNA was assessed by qRT-PCR, Western blotting and hormone assay. After subcapsular injection of lentivirus shRNA in rat ovary, the delivery efficiency was evaluated by GFP fluorescence and qPCR. Total RNA was extracted from rat ovary for CYP17 mRNA determination and rat serum was collected for hormone measurement.</p> <p>Results</p> <p>In total, three CYP17-targeting lentivirus shRNAs were synthesized. The results showed that all of them had a silencing effect on CYP17 mRNA and protein. Moreover, androstenedione secreted by rat theca interstitial cells (TIC) in the RNAi group declined significantly compared with that in the control group. Two weeks after rat ovarian subcapsular injection of chosen CYP17 shRNA, the GFP fluorescence of frozen ovarian sections could be seen clearly under fluorescence microscope. It also showed that the GFP DNA level increased significantly, and its relative expression level was 7.42 times higher than that in the control group. Simultaneously, shRNA treatment significantly decreased CYP17 mRNA and protein levels at 61% and 54%, respectively. Hormone assay showed that all the levels of androstenedione, 17-hydroxyprogesterone and testosterone declined to a certain degree, but progesterone levels declined significantly.</p> <p>Conclusion</p> <p>The present study proves for the first time that ovarian androgen biosynthesis can be inhibited by silencing CYP17 expression. It may provide a novel strategy for therapy of hyperandrogenism diseases, and also set an example for the use of RNAi technology in endocrine diseases.</p

荆州区农村人口初发糖尿病胰岛功能的现状跟踪调查*

Objective: To study the change of islet function in patients with incipient diabetic characteristics through incipient diabetic tracking observation of the islet function in patients of Jingzhou area. Methods: Selection of 1220 cases of patients with diabetes mellitus in Jingzhou area as research object at the beginning, 12 months follow-up, the clinic after 3 months, 6 months and 12 months, all patients to detect blood sugar change, c-peptide release quantity, calculate insulin secretion index (HOMA -β) and insulin resistance index (HOMA IR), summarizes the characteristic of islet function in patients with changes. Results: ① The patients restored to basic standard blood sugar in 3 months by drug treatment, and the patient's blood glucose levels not seen obvious fluctuation after 6 months and 12 months; ② During follow-up, patients with diabetes sustained c-peptide release quantity reduction, and in three months after treatment, c-peptide release decreased obviously, and see a doctor at 6 months and 12 months after the comparison, the difference was statistically significant (P &lt; 0.05). ③ During follow-up, insulin capacity was decreasing among patients with diabetes, within three months after the doctor had the greatest reduction, the difference was statistically significant (P &lt; 0.05); ④ During follow-up, island hormone decreasing index, insulin resistance index continued to rise among patients with diabetes, and 6 months and 12 months, the most significant variations in 3 months (P &lt; 0.05). Conclusion: With the extension of course, the pancreatic islet function in patients with early onset diabetes decreased gradually. It could be proved that there is a significant correlation between the two and especially seen in obvious function decline of pancreatic islets among the patients within 3 months.目的  通过对荆州区初发糖尿病患者的胰岛功能进行跟踪观察，探讨发现初发糖尿病患者胰岛功能的变化特点。方法  选取荆州区1220例初发糖尿病患者作为观察对象，跟踪随访12个月，在就诊后的3个月、6个月及12个月时，全部患者检测血糖变化、Ｃ-肽释放量，计算胰岛素分泌指数（HOMA-β）及胰岛素抵抗指数（HOMA-IR），观察总结患者的胰岛功能变化特点。结果  （1）通过药物治疗，患者血糖在3个月时基本达标，6个月及12个月时，患者的血糖水平未见明显波动；（2）随访期间，糖尿病患者Ｃ-肽释放量持续降低，且在就诊后3个月内，Ｃ-肽释放量下降明显，与就诊后6个月时及12个月时比较，差异有统计学意义（P＜0.05）。（3）随访期间，糖尿病患者胰岛素放量持续降低，就诊后3个月内下降最明显，差异有统计学意义（P＜0.05）；（4）随访期间，糖尿病患者胰岛素分泌指数持续降低，胰岛素抵抗指数持续升高，且与6个月时和12个月时比较，3个月时变化幅度最为显著（P＜0.05）。结论  随着病程的延长，初发糖尿病患者胰岛功能逐渐降低，二者具有显著相关性，且3个月内患者的胰岛功能下降最为显著

GuiErBai: a potent inhibitor, exhibiting broadly antitumor effect against cervical cancer in vitro and in vivo

Introduction: Cervical cancer (CC) ranks as the fourth most prevalent malignant tumor among women worldwide, and is the fourth leading cause of cancer-related mortality. GuiErBai (GEB), a compound preparation developed by our research team, is derived from the ancient Chinese medicine of the Miao nationality and is comprised of podophyllotoxin (PTOX), imperatorin, isoimperatorin, and A. dahurica alkaloids. These individual components have demonstrated notable efficacy in tumor treatment. However, the specific anti-tumor effect of the compound Chinese medicine GEB in the context of CC has yet to be validated.Methods: HeLa and SiHa cell lines were utilized for in vitro experiments and treated with 5 mg/mL and 10 mg/mL GEB concentrations, respectively. The cell cycle changes after GEB treatment were assessed using flow cytometry. Transmission electron microscopy was employed to observe autophagic bodies and apoptotic bodies, while MDC staining evaluated the occurrence of autophagy. CCK-8 was used to observe the effect of GEB on cell proliferation, and Transwell assays assessed cell migration and invasion. Western blotting detected cell cycle and apoptosis-related protein expression, along with the expression level of autophagy-related protein LC3I/II. Changes in ROS and mitochondrial membrane potential in cervical cancer cells following GEB treatment were determined using ROS detection and mitochondrial membrane potential detection kits. For the in vivo experiment, a nude mouse model of cervical cancer transplantation based on HeLa cells was established. Experimental animals were divided into negative control, positive control, high-dose GEB (10 mg/mL), and low-dose GEB (5 mg/mL) groups.Results: In HeLa and SiHa cell lines, the G0/G1 phase of tumor cells significantly decreased (p &lt; 0.001), while the G2/M phase increased notably (p &lt; 0.001) following various GEB treatments. Electron microscopy showed GEB promoted apoptotic body and autophagosome formation in both cell lines. Compared to untreated HeLa and SiHa cells, GEB-treated cells exhibited significantly reduced caspase3 protein expression, and substantially increased autophagy-related protein LC3I/II expression. GEB treatment significantly reduced migration and invasion capabilities in both cell lines (p &lt; 0.001), while ROS content and mitochondrial membrane potential were significantly elevated (p &lt; 0.001). GEB effectively inhibited cervical cancer cell proliferation, with the optimal concentration being 10 mg/mL. A successful nude mouse model of cervical cancer transplantation was established using HeLa cells. Post-GEB treatment, the tumor volume and weight in nude mice significantly decreased (p &lt; 0.001), with diminished expression of CD34, VEGF, and caspase3 proteins in tumor tissues.Discussion: GEB exhibits a robust antitumor effect against cervical cancer, both in vitro and in vivo, in a concentration-dependent manner, by regulating autophagy and apoptosis of tumor cells

Influence of hypoxia on retinal progenitor and ganglion cells in human induced pluripotent stem cell-derived retinal organoids

AIM: To observe the effect of low oxygen concentration on the neural retina in human induced pluripotent stem cell (hiPSC)-derived retinal organoids (ROs). METHODS: The hiPSC and a three-dimensional culture method were used for the experiments. Generated embryoid bodies (EBs) were randomly and equally divided into hypoxic and normoxic groups. Photographs of the EBs were taken on days 38, 45, and 52, and the corresponding volume of EBs was calculated. Simultaneously, samples were collected at these three timepoints, followed by fixation, sectioning, and immunofluorescence. RESULTS: The proportion of Ki67-positive proliferating cells increased steadily on day 38; this proliferation-promoting effect tended to increase tissue density rather than tissue volume. On days 45 and 52, the two groups had relatively similar ratios of Ki67-positive cells. Further immunofluorescence analysis showed that the ratio of SOX2-positive cells significantly increased within the neural retina on day 52 (P0.05). Moreover, the proportion of PAX6-/TUJ1+ cells within the neural retinas increased considerably (P<0.01, <0.05, <0.05 respectively). CONCLUSION: Low oxygen promotes stemness and proliferation of neural retinas, suggesting that hypoxic conditions can enlarge the retinal progenitor cell pool in hiPSC-derived ROs

Quantitative learning strategies based on word networks

Learning English requires a considerable effort, but the way that vocabulary is introduced in textbooks is not optimized for learning efficiency. With the increasing population of English learners, learning process optimization will have significant impact and improvement towards English learning and teaching. The recent developments of big data analysis and complex network science provide additional opportunities to design and further investigate the strategies in English learning. In this paper, quantitative English learning strategies based on word network and word usage information are proposed. The strategies integrate the words frequency with topological structural information. By analyzing the influence of connected learned words, the learning weights for the unlearned words and dynamically updating of the network are studied and analyzed. The results suggest that quantitative strategies significantly improve learning efficiency while maintaining effectiveness. Especially, the optimized-weight-first strategy and segmented strategies outperform other strategies. The results provide opportunities for researchers and practitioners to reconsider the way of English teaching and designing vocabularies quantitatively by balancing the efficiency and learning costs based on the word network

Synchrotron Radiation Dominates the Extremely Bright GRB 221009A

The brightest Gamma-ray burst, GRB 221009A, has spurred numerous theoretical investigations, with particular attention paid to the origins of ultra-high energy TeV photons during the prompt phase. However, analyzing the mechanism of radiation of photons in the $\sim$MeV range has been difficult because the high flux causes pile-up and saturation effects in most GRB detectors. In this letter, we present systematic modeling of the time-resolved spectra of the GRB using unsaturated data obtained from Fermi/GBM (precursor) and SATech-01/GECAM-C (main emission and flare). Our approach incorporates the synchrotron radiation model, which assumes an expanding emission region with relativistic speed and a global magnetic field that decays with radius, and successfully fits such a model to the observational data. Our results indicate that the spectra of the burst are fully in accordance with a synchrotron origin from relativistic electrons accelerated at a large emission radius. The lack of thermal emission in the prompt emission spectra supports a Poynting-flux-dominated jet composition.Comment: 12 pages, 6 figures, 2 tables. Accepted for publication in ApJ

Genome-Wide Association Study for Femoral Neck Bone Geometry

Poor femoral neck bone geometry at the femur is an important risk factor for hip fracture. We conducted a genome-wide association study (GWAS) of femoral neck bone geometry, examining approximately 379,000 eligible single-nucleotide polymorphisms (SNPs) in 1000 Caucasians. A common genetic variant, rs7430431 in the receptor transporting protein 3 (RTP3) gene, was identified in strong association with the buckling ratio (BR, P = 1.6 × 10−7), an index of bone structural instability, and with femoral cortical thickness (CT, P = 1.9 × 10−6). The RTP3 gene is located in 3p21.31, a region that we found to be linked with CT (LOD = 2.19, P = 6.0 × 10−4) in 3998 individuals from 434 pedigrees. The replication analyses in 1488 independent Caucasians and 2118 Chinese confirmed the association of rs7430431 to BR and CT (combined P = 7.0 × 10−3 for BR and P = 1.4 × 10−2 for CT). In addition, 350 hip fracture patients and 350 healthy control individuals were genotyped to assess the association of the RTP3 gene with the risk of hip fracture. Significant association between a nearby common SNP, rs10514713 of the RTP3 gene, and hip fracture (P = 1.0 × 10−3) was found. Our observations suggest that RTP3 may be a novel candidate gene for femoral neck bone geometry. © 2010 American Society for Bone and Mineral Researc