Mixed-Dimensional Partial Dealloyed PtCuBi/C as High-Performance Electrocatalysts for Methanol Oxidation with Enhanced CO Tolerance.

Developing efficient electrocatalysts for methanol oxidation reaction (MOR) is crucial in advancing the commercialization of direct methanol fuel cells (DMFCs). Herein, carbon-supported 0D/2D PtCuBi/C (0D/2D PtCuBi/C) catalysts are fabricated through a solvothermal method, followed by a partial electrochemical dealloying process to form a novel mixed-dimensional electrochemically dealloyed PtCuBi/C (0D/2D D-PtCuBi/C) catalysts. Benefiting from distinctive mixed-dimensional structure and composition, the as-obtained 0D/2D D-PtCuBi/C catalysts possess abundant accessible active sites. The introduction of Cu as a water-activating element weakens the COads, and oxophilic metal Bi facilitates the OHads, thereby enhancing its tolerance to CO poisoning and promoting MOR activity. The X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure spectroscopy (XAFS) collectively reveal the electron transfer from Cu and Bi to Pt, the electron-enrichment effect induced by dealloying, and the strong interactions among Pt-M (Cu, Pt, and Bi) multi-active sites, which improve the tuning of the electronic structure and enhancement of electron transfer ability. Impressively, the optimized 0D/2D D-PtCuBi/C catalysts exhibit the superior mass activity (MA) of 17.68 A mgPt -1 for MOR, which is 14.86 times higher than that of commercial Pt/C. This study offers a proposed strategy for Pt-based alloy catalysts, enabling their use as efficient anodic materials in fuel cell applications.

Screening/diagnosis of pediatric endocrine disorders through the artificial intelligence model in different language settings.

This study is aimed at examining the impact of ChatGPT on pediatric endocrine and metabolic conditions, particularly in the areas of screening and diagnosis, in both Chinese and English modes. A 40-question questionnaire covering the four most common pediatric endocrine and metabolic conditions was posed to ChatGPT in both Chinese and English three times each. Six pediatric endocrinologists evaluated the responses. ChatGPT performed better when responding to questions in English, with an unreliable rate of 7.5% compared to 27.5% for Chinese questions, indicating a more consistent response pattern in English. Among the reliable questions, the answers were more comprehensive and satisfactory in the English mode. We also found disparities in ChatGPT's performance when interacting with different target groups and diseases, with improved performance for questions posed by clinicians in English and better performance for questions related to diabetes and overweight/obesity in Chinese for both clinicians and patients. Language comprehension, providing incomprehensive answers, and errors in key data were the main contributors to the low scores, according to reviewer feedback. CONCLUSION: Despite these limitations, as ChatGPT continues to evolve and expand its network, it has significant potential as a practical and effective tool for clinical diagnosis and treatment. WHAT IS KNOWN: • The deep learning-based large-language model ChatGPT holds great promise for improving clinical practice for both physicians and patients and has the potential to increase the speed and accuracy of disease screening and diagnosis, as well as enhance the overall efficiency of the medical process. However, the reliability and appropriateness of AI model responses in specific field remains unclear. • This study focused on the reliability and appropriateness of AI model responses to straightforward and fundamental questions related to the four most prevalent pediatric endocrine and metabolic disorders, for both healthcare providers and patients, in different language scenarios. WHAT IS NEW: • The AI model performed better when responding to questions in English, with more consistent, as well as more comprehensive and satisfactory responses. In addition, we also found disparities in ChatGPT's performance when interacting with different target groups and different diseases. • Despite these limitations, as ChatGPT continues to evolve and expand its network, it has significant potential as a practical and effective tool for clinical diagnosis and treatment.

Overexpression of a nuclear receptor HR96 contributes to spirodiclofen susceptibility in Panonychus citri (McGregor).

The citrus red mite, Panonychus citri, is one of the most notorious and devastating citrus pests around the world that has developed resistance to multiple chemical acaricides. In previous research, we found that spirodiclofen-resistant is related to overexpression of P450, CCE, and ABC transporter genes in P. citri. However, the regulatory mechanisms of these detoxification genes are still elusive. This study identified all hormone receptor 96 genes of P. citri. 8 PcHR96 genes contained highly conserved domains. The expression profiles showed that PcHR96h was significantly upregulated in spirodiclofen resistant strain and after exposure to spirodiclofen. RNA interference of PcHR96h decreased expression of detoxification genes and increased spirodiclofen susceptibility in P. citri. Furthermore, molecular docking, heterologous expression, and drug affinity responsive target stability demonstrated that PcHR96h can interact with spirodiclofen in vitro. Our research results indicate that PcHR96h plays an important role in regulating spirodiclofen susceptibility and provides theoretical support for the resistance management of P. citri.

miR-4433a-3p promotes granulosa cell apoptosis by targeting peroxisome proliferator-activated receptor alpha and inducing immune cell infiltration in polycystic ovarian syndrome.

BACKGROUND: Granulosa cell (GC) proliferation and apoptosis are critical events of the ovum energy supply, which lead to follicular growth retardation or atresia, and various ovulatory obstacles, eventually resulting in the development of ovarian disorders such as polycystic ovarian syndrome (PCOS). Apoptosis and dysregulated miRNA expression in GCs are manifestations of PCOS. miR-4433a-3p has been reported to be involved in apoptosis. However, there is no study reporting the roles of miR-4433a-3p in GC apoptosis and PCOS progression. METHODS: miR-4433a-3p and peroxisome proliferator-activated receptor alpha (PPAR-α) levels in GCs of PCOS patients or in tissues of a PCOS rat model were examined by quantitative polymerase chain reaction and immunohistochemistry. Bioinformatics analyses and luciferase assays were used to examine the association between miR-4433a-3p and PPAR-α, as well as PPAR-α and immune cell infiltration, in PCOS patients. RESULTS: miR-4433a-3p expression in GCs of PCOS patients was increased. miR-4433a-3p overexpression inhibited the growth of the human granulosa-like tumor cell line (KGN) and promoted apoptosis, while co-treatment with PPAR-α and miR-4433a-3p mimic rescued miR-4433a-3p-induced apoptosis. PPAR-α was a direct target of miR-4433a-3p and its expression was decreased in PCOS patients. PPAR-α expression was also positively correlated with the infiltration of activated CD4+ T cells, eosinophils, B cells, gamma delta T cells, macrophages, and mast cells, but negatively correlated with the infiltration of activated CD8+ T cells, CD56+ bright natural killer cells, immature dendritic cells, monocytes, plasmacytoid dendritic cells, neutrophils, and type 1 T helper cells in PCOS patients. CONCLUSION: The miR-4433a-3p/PPAR-α/immune cell infiltration axis may function as a novel cascade to alter GC apoptosis in PCOS.

Comparative Transcriptomic and Physiological Analyses Reveal Key Factors for Interstocks to Improve Grafted Seedling Growth in Tangor.

Interstock is an important agronomic technique for regulating plant growth and fruit quality, and overcoming the incompatibility between rootstocks and scions; however, the underlying mechanisms remain largely unknown. In this study, the effects and regulatory mechanisms of tangor grafting, with and without interstocks, on the growth and development of scions were analyzed by combining morphology, physiology, anatomy and transcriptomics. Morphological and physiological analyses showed that interstocks ('Aiyuan 38' and 'Daya') significantly improved the growth of seedlings, effectively enhanced the foliar accumulation of chlorophyll and carotenoids, and increased the thickness of leaf tissues. Using 'Aiyuan 38' as the interstock, photosynthetic efficiency and starch content of citrus seedlings improved. Transcriptomics showed that genes related to photosynthesis and photosynthetic antenna proteins were upregulated in interstock-treated seedlings, with significant upregulation of photosystem PSI- and PSII-related genes. In addition, multiple key genes may be involved in plant hormone signaling, starch and sucrose metabolism, and transcriptional regulation. Taken together, these findings provide novel insights into the role of interstocks in regulating and contributing to the growth and development of grafted seedlings, and will further define and deploy candidate genes to explore the mechanisms of rootstock-interstock-scion interactions.

Inactivated COVID-19 vaccination does not affect in vitro fertilization outcomes in women.

STUDY QUESTION: Do inactivated coronavirus disease-2019 (COVID-19) vaccines affect IVF outcomes among the vaccine recipients? SUMMARY ANSWER: The receipt of inactivated COVID-19 vaccines before ovarian stimulation has little effect on the outcomes of IVF, including ovarian stimulation outcomes, embryo development and pregnancy rates. WHAT IS KNOWN ALREADY: Limited studies have reported that COVID-19 vaccines do not affect ovarian function, embryo development or pregnancy outcomes. STUDY DESIGN, SIZE, DURATION: This was a retrospective cohort study performed at the Third Affiliated Hospital of Guangzhou Medical University on 240 women vaccinated with either CoronaVac or Sinopharm COVID-19 before ovarian stimulation in the exposed group and 1343 unvaccinated women before ovarian stimulation in the unexposed group. All participants received fresh embryo transfers between 1 March 2021 and 15 September 2021. The included women were followed up until 12 weeks of gestation. PARTICIPANTS/MATERIALS, SETTING, METHODS: Vaccination information of all subjects was followed up by a nurse, and the IVF data were obtained from the IVF data system. The following aspects were compared between the vaccinated and the unvaccinated groups: parameters of ovarian stimulation, embryo development and pregnancy rates. Regression analyses were performed to control for confounders of embryo development and pregnancy rates. Propensity score matching (PSM) was performed to balance the baseline parameters of the two groups. The primary outcome was the ongoing pregnancy rate. MAIN RESULTS AND THE ROLE OF CHANCE: Liner regression analysis revealed that the number of oocytes retrieved (regression coefficient (B) = -0.299, P = 0.264), embryos suitable for transfer (B = -0.203, P = 0.127) and blastocysts (B = -0.250, P = 0.105) were not associated with the status of vaccination before ovarian stimulation, after adjusting for the confounders. The ongoing pregnancy rate in the women of the vaccinated group was not significantly lower than that in the unvaccinated group (36.3% vs 40.7%, P = 0.199) (adjust odd ratio = 0.91, 95% CI = 0.68-1.22, P = 0.52). After PSM, the rates of ongoing pregnancy (36.0% vs 39.9%, P = 0.272), implantation (35.4% vs 38.3%, P = 0.325), biochemical pregnancy (47.3% vs 51.6%, P = 0.232), clinical pregnancy (44.4% vs 47.4%, P = 0.398) and early miscarriage (15.0% vs 12.1%, P = 0.399) were not significantly different between the vaccinated and the unvaccinated groups. LIMITATIONS, REASONS FOR CAUTION: This is a retrospective study of women with infertility. The results from the present study warrant confirmation by prospective studies with a larger cohort. WIDER IMPLICATIONS OF THE FINDINGS: This is the first study with a large sample size on the effect of inactivated COVID-19 vaccines on ongoing pregnancy rates of women undergoing IVF. The present results showed that vaccination has no detrimental effect on IVF outcomes. Therefore, women are recommended to receive COVID-19 vaccines before undergoing their IVF treatment. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the National Key Research and Development Program of China (No. 2018YFC1003803 to J.L.), the Guangzhou Science and Technology Plan Project (No. 202102010076 to H.L.) and the Medical Key Discipline of Guangzhou (2021-2023), as well as the Sino-German Center for Research Promotion Rapid Response Funding Call for Bilateral Collaborative Proposals between China and Germany in COVID-19 Related Research (No. C-0032 to Xingfei Pan). The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

Inactivated Covid-19 vaccine did not undermine live birth and neonatal outcomes of women with frozen-thawed embryo transfer.

STUDY QUESTION: Does inoculation with inactivated vaccines against coronavirus disease 2019 (Covid-19) before frozen-thawed embryo transfer (FET) affect live birth and neonatal outcomes? SUMMARY ANSWER: Inactivated Covid-19 vaccines did not undermine live birth and neonatal outcomes of women planning for FET. WHAT IS KNOWN ALREADY: Accumulating reports are now available indicating the safe use of mRNA vaccines against Covid-19 in pregnant and lactating women, and a few reports indicate that they are not associated with adverse effects on ovarian stimulation or early pregnancy outcomes following IVF. Evidence about the safety of inactivated Covid-19 vaccines is very limited. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort analysis from Reproductive Medical Center of a tertiary teaching hospital. Clinical records and vaccination record of 2574 couples with embryos transferred between 1 March 2021 and 30 September 2021 were screened for eligibility of this study. PARTICIPANTS/MATERIALS, SETTING, METHODS: Clinical and vaccination data of infertile couples planning for FET were screened for eligibility of the study. The reproductive and neonatal outcomes of FET women inoculated with inactivated Covid-19 vaccines or not were compared. The primary outcomes were live birth rate per embryo transfer cycle and newborns' birth height and weight. Secondary outcomes included rates of ongoing pregnancy, clinical pregnancy, biochemical pregnancy and spontaneous miscarriage. Multivariate logistical regression and propensity score matching (PSM) analyses were performed to minimize the influence of confounding factors. Subgroup analyses, including single dose versus double dose of the vaccines and the time intervals between the first vaccination and embryo transfer, were also performed. MAIN RESULTS AND THE ROLE OF CHANCE: Vaccinated women have comparable live birth rates (43.6% versus 45.0% before PSM, P = 0.590; and 42.9% versus 43.9% after PSM, P = 0.688), ongoing pregnancy rates (48.2% versus 48.1% before PSM, P = 0.980; and 52.2% versus 52.7% after PSM, P = 0.875) and clinical pregnancy rate (55.0% versus 54.8% before PSM, P = 0.928; and 54.7% versus 54.2% after PSM, P = 0.868) when compared with unvaccinated counterparts. The newborns' birth length (50.0 ± 1.6 versus 49.0 ± 2.9 cm before PSM, P = 0.116; and 49.9 ± 1.7 versus 49.3 ± 2.6 cm after PSM, P = 0.141) and birth weight (3111.2 ± 349.9 versus 3030.3 ± 588.5 g before PSM, P = 0.544; and 3053.8 ± 372.5 versus 3039.2 ± 496.8 g after PSM, P = 0.347) were all similar between the two groups. Neither single dose nor double dose of vaccines, as well as different intervals between vaccination and embryo transfer showed any significant impacts on reproductive and neonatal outcomes. LIMITATIONS, REASONS FOR CAUTION: The main findings might be limited by retrospective design. Besides, inoculations of triple dose of Covid-19 vaccines were not available by the time of data collection, thus the results cannot reflect the safe use of triple dose of inactivated Covid-19 vaccines. Finally, history of Covid-19 infection was based on patients' self-report rather than objective laboratory tests. WIDER IMPLICATIONS OF THE FINDINGS: Eligible individuals of inactivated vaccines against Covid-19 should not postpone vaccination plan because of their embryo transfer schedule, or vice versa. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the Medical Key Discipline of Guangzhou (2021-2023). All authors had nothing to disclose. TRIAL REGISTRATION NUMBER: N/A.

First Request First Service Entanglement Routing Scheme for Quantum Networks.

Quantum networks enable many applications beyond the reach of classical networks by supporting the establishment of long-distance entanglement connections, and are already stepped into the entanglement distribution network stage. The entanglement routing with active wavelength multiplexing schemes is urgently required for satisfying the dynamic connection demands of paired users in large-scale quantum networks. In this article, the entanglement distribution network is modeled into a directed graph, where the internal connection loss among all ports within a node is considered for each supported wavelength channel, which is quite different to classical network graphs. Afterwards, we propose a novel first request first service (FRFS) entanglement routing scheme, which performs the modified Dijkstra algorithm to find out the lowest loss path from the entangled photon source to each paired user in order. Evaluation results show that the proposed FRFS entanglement routing scheme can be applied to large-scale and dynamic topology quantum networks.

Management of 14 patients with cornual heterotopic pregnancy following embryo transfer: experience from the past decade.

OBJECTIVE: There are two major management approach for cornual heterotopic pregnancy, transvaginal cornual embryo reduction with ultrasound guidance, or laparoscopic cornual resection. This no consensus on the optimal management for cornual heterotopic pregnancy. Here, we are trying to determine the optimal management approach for patients with viable cornual heterotopic pregnancy following embryo transfer. METHODS: This is a retrospective cohort study conducted at the locally largest reproductive center of a tertiary hospital. A total of 14 women diagnosed as viable cornual heterotopic pregnancy following embryo transfer. Six patients were treated with cornual pregnancy reduction under transvaginal ultrasound guidance without the use of feticide drug (treatment 1), and eight patients were treated with laparoscopic cornual pregnancy resection (treatment 2). RESULTS: All 14 patients of cornual heterotopic pregnancy following embryo transfer due to fallopian tubal factor, among which, 12 patients had cornual pregnancy occurred in the ipsilateral uterine horn of tubal pathological conditions. Nine (64.29%) showed a history of ectopic pregnancy. Thirteen (92.86%) patients were transferred with two embryos and only one patient had single embryo transferred. Six patients received treatment 1, and 2 (33.33%) had uterine horn rupture and massive bleeding which required emergency laparoscopic surgery for homostasis. No cornual rupture occurred among patients received treatment 2. Each treatment group had one case of spontaneous miscarriage. The remaining 5 cases in treatment 1 group and the remaining 7 cases in treatment 2 group delivered healthy live offspring. CONCLUSION: Patients with tubal factors attempting for embryo transfer, especially those aiming for multiple embryos transfer, should be informed with risk of cornual heterotopic pregnancy and the subsequent cornual rupture. Compared with cornual pregnancy reduction under transvaginal ultrasound guidance, laparoscopic cornual resection might be a favorable approach for patients with viable cornual heterotopic pregnancy.

Anticentromere antibody induced by immunization with centromere protein a and Freund's complete adjuvant may interfere with mouse oocyte meiosis.

BACKGROUND: Anticentromere antibody (ACA) is a member of the antinuclear antibody (ANA) family, and recent studies have found that ACA may be associated with oocyte maturation disorders; however, the possible mechanism behind this phenomenon remains unknown. We conducted this study to investigate whether ACA could penetrate into the living oocytes and interfere with oocyte meiosis in a mouse model. METHODS: We divided mice into three groups: human recombinant centromere protein-A (human CENP-A, HA) and complete Freund's adjuvant (CFA) were used to immunize mice for the study group (HA + CFA), and mice injected with CFA (CFA group) or saline (Saline group), respectively, served as controls. After immunization, serum anti-CENP-A antibody was detected by indirect immunofluorescence assay (IIFT) and enzyme-linked immunosorbent assay (ELISA). Chromosome alignment and intracellular IgG localization in MI- and MII-stage oocytes were investigated by immunofluorescence analysis. RESULTS: Positive ACAs were successfully induced by immunization with CENP-A and CFA, and results showed that the serum level of anti-CENP-A antibody was significantly higher in the HA + CFA group compared with the control groups. There was marked increase of chromosome misalignments in MI and MII oocytes in the HA + CFA group compared to the control groups. However, no oocytes from any of the three groups showed intracellular antibody immunofluorescence. CONCLUSIONS: The development and maturation of oocytes were impaired in peripheral ACA positive mice, which exhibited severe chromosomal misalignments in metaphase meiosis; however, no evidence of ACAs entering the oocytes was observed, thus the underlying mechanism needs further exploration.

microRNA-194 is increased in polycystic ovary syndrome granulosa cell and induce KGN cells apoptosis by direct targeting heparin-binding EGF-like growth factor.

BACKGROUND: Polycystic ovary syndrome (PCOS) is an endocrine-related follicular developmental disorder that affects 50 %-70 % of reproductive-aged women diagnosed with ovulation-related infertility. Abnormal proliferation and apoptosis of granulosa cells (GCs) are thought to be the critical factors leading to abnormal maturation of follicles. It has been shown that microRNAs (miRNAs) exert a significant influence in the pathogenesis of PCOS; however, the relationship between miRNA, PCOS, and GC apoptosis is not entirely understood. METHODS: To clarify the effect of miR-194 in PCOS, CCK-8, Ki67 staining, AO/EB, and flow cytometry assays were used to assess cell growth, proliferation, and apoptosis in KGN cells, which were artificially stimulated to overexpress miR-194. Luciferase reporter assays and rescue experiments were used to elucidate the mechanism underlying miR-194 in PCOS. RESULTS: miR-194 expression was significantly up-regulated in rat models of PCOS and the ovarian GCs of PCOS patients. miR-194 suppression promoted KGN cell growth and proliferation. miR-194 overexpression also induced cell apoptosis, while miR-194 downregulation had an opposite effect. Furthermore, up-regulating heparin-binding EGF-like growth factor (HB-EGF) expression rescued the pro-apoptotic effects of miR-194 upregulation on KGN cells. CONCLUSIONS: miR-194 is increased in PCOS granulosa cell and may function as a novel biomarker and therapeutic target for KGN cells via HB-EGF regulation.

LncRNA TUG1 functions as a ceRNA for miR-6321 to promote endothelial progenitor cell migration and differentiation.

Endothelial progenitor cell (EPC) recruitment and angiogenesis play crucial roles in aneurysm neck endothelialization, but the mechanisms of EPC recruitment and angiogenesis are still unclear. Recent studies have shown that long noncoding RNAs (lncRNAs) can regulate the function and differentiation of cells in various ways. LncRNA TUG1 is involved in liver cancer and glioma-mediated angiogenesis. The aim of this study was to investigate the role of lncRNA TUG1 in regulating EPC migration and differentiation. Overexpression and knockdown of lncRNA TUG1 with lentivirus, scratch assays, Transwell assays and tube formation assays using EPCs isolated from rat bone marrow showed that lncRNA TUG1 overexpression promoted EPC migration, invasion and differentiation. Moreover, ELISAs showed that lncRNA TUG1 overexpression increased VEGF expression. Bioinformatics prediction, luciferase assays, Western blots and RIP assays indicated that lncRNA TUG1 functions as a ceRNA (competing endogenous RNA) for miR-6321 and that miR-6321 inhibits EPC migration and differentiation through its target, ATF2. As a potential therapeutic target, lncRNA TUG1 may play a vital role in the pathogenesis of aneurysms.

A heparin-rosuvastatin-loaded P(LLA-CL) nanofiber-covered stent inhibits inflammatory smooth-muscle cell viability to reduce in-stent stenosis and thrombosis.

BACKGROUND: An endovascular covered-stent has unique advantages in treating complex intracranial aneurysms; however, in-stent stenosis and late thrombosis have become the main factors affecting the efficacy of covered-stent treatment. Smooth-muscle-cell phenotypic modulation plays an important role in late in-stent stenosis and thrombosis. Here, we determined the efficacy of using covered stents loaded with drugs to inhibit smooth-muscle-cell phenotypic modulation and potentially lower the incidence of long-term complications. METHODS: Nanofiber-covered stents were prepared using coaxial electrospinning, with the core solution prepared with 15% heparin and 20 µM rosuvastatin solution (400: 100 µL), and the shell solution prepared with 120 mg/mL hexafluoroisopropanol. We established a rabbit carotid-artery aneurysm model, which was treated with covered stents. Angiography and histology were performed to evaluate the therapeutic efficacy and incidence rate of in-stent stenosis and thrombosis. Phenotype, function, and inflammatory factors of smooth-muscle cells were studied to explore the mechanism of rosuvastatin action in smooth-muscle cells. RESULT: Heparin-rosuvastatin-loaded nanofiber scaffold mats inhibited the proliferation of synthetic smooth-muscle cells, and the nanofiber-covered stent effectively treated aneurysms in the absence of notable in-stent stenosis. Additionally, in vitro experiments showed that rosuvastatin inhibited the smooth-muscle-cell phenotypic modulation of platelet-derived growth factor-BB induction and decreased synthetic smooth-muscle-cell viability, as well as secretion of inflammatory cytokines. CONCLUSION: Rosuvastatin inhibited the abnormal proliferation of synthetic smooth-muscle cells, and heparin-rosuvastatin-loaded covered stents reduced the incidence of stenosis and late thrombosis, thereby improving the healing rates of stents used for aneurysm treatment.

Metformin inhibits intracranial aneurysm formation and progression by regulating vascular smooth muscle cell phenotype switching via the AMPK/ACC pathway.

BACKGROUND: The regulation of vascular smooth muscle cell (VSMC) phenotype plays an important role in intracranial aneurysm (IA) formation and progression. However, the underlying mechanism remains unclear. Metformin is a 5' AMP-activated protein kinase (AMPK) agonist that has a protective effect on vasculature. The present study investigated whether metformin modulates VSMC phenotype switching via the AMPK/acetyl-CoA carboxylase (ACC) pathway during IA pathogenesis. METHODS: Adult male Sprague-Dawley rats (n = 80) were used to establish an elastase-induced IA model. The effects of metformin on AMPK activation and VSMC phenotype modulation were examined. We also established a platelet-derived growth factor (PDGF)-BB-induced VSMC model and analyzed changes in phenotype including proliferation, migration, and apoptosis as well as AMPK/ACC axis activation under different doses of metformin, AMPK antagonist, ACC antagonist, and their combinations. RESULTS: Metformin decreased the incidence and rupture rate of IA in the rat model and induced a switch in VSMC phenotype from contractile to synthetic through activation of the AMPK/ACC pathway, as evidenced by upregulation of VSMC-specific genes and decreased levels of pro-inflammatory cytokines. AMPK/ACC axis activation inhibited the proliferation, migration, and apoptosis of VSMCs, in which phenotypic switching was induced by PDGF-BB. CONCLUSIONS: Metformin protects against IA formation and rupture by inhibiting VSMC phenotype switching and proliferation, migration, and apoptosis. Thus, metformin has therapeutic potential for the prevention of IA.

Nrf-2 signaling inhibits intracranial aneurysm formation and progression by modulating vascular smooth muscle cell phenotype and function.

BACKGROUND: Oxidative stress and vascular smooth muscle cell (VSMC) phenotypic modulation influence intracranial aneurysm (IA) formation and progression. Oxidative stress plays an important role in phenotype switching, and nuclear factor erythroid 2-related factor 2 (Nrf-2) is one of the main antioxidant systems. Unfortunately, little is known about how Nrf-2 signaling influences VSMC phenotype switches during IA pathogenesis. METHODS: We examined the effect of Nrf-2 activation IA on formation and progression in an elastase-induced rat IA model. We also developed a hydrogen peroxide (H2O2)-induced VSMC oxidative damage model. Then, we analyzed VSMC phenotype changes in the setting of Nrf-2 activation or inhibition in vitro. The proliferation, migration ability, and apoptosis rate of VSMCs were tested. Lastly, we measured the expression levels of antioxidant enzymes and inflammatory cytokines downstream of Nrf-2. RESULTS: Nrf-2 activation suppressed IA formation and progression in vivo. We confirmed Nrf-2 nuclear translocation and a VSMC switch from the contractile to synthetic phenotype. Nrf-2 activation inhibited the proliferation, migratory ability, and apoptosis rate enhanced by H2O2. Quantitative real-time polymerase chain reaction (PCR) and western blot analysis revealed that Nrf-2 activation promoted antioxidant enzymes and VSMC-specific marker gene expressions but decreased pro-inflammatory cytokine levels. CONCLUSION: These results suggest that Nrf-2 exerts protective effects against IA development by preventing VSMCs from changing to a synthetic phenotype.

SPINT2 is hypermethylated in both IDH1 mutated and wild-type glioblastomas, and exerts tumor suppression via reduction of c-Met activation.

PURPOSE: Both IDH1-mutated and wild-type gliomas abundantly display aberrant CpG island hypermethylation. However, the potential role of hypermethylation in promoting gliomas, especially the most aggressive form, glioblastoma (GBM), remains poorly understood. METHODS: We analyzed RRBS-generated methylation profiles for 11 IDH1WT gliomas (including 7 GBMs), 24 IDH1MUT gliomas (including 6 GBMs), and 5 normal brain samples and employed TCGA GBM methylation profiles as a validation set. Upon classification of differentially methylated CpG islands by IDH1 status, we used integrated analysis of methylation and gene expression to identify SPINT2 as a top cancer related gene. To explore functional consequences of SPINT2 methylation in GBM, we validated SPINT2 methylation status using targeted bisulfite sequencing in a large cohort of GBM samples. We assessed DNA methylation-mediated SPINT2 gene regulation using 5-aza-2'-deoxycytidine treatment, DNMT1 knockdown and luciferase reporter assays. We conducted functional analyses of SPINT2 in GBM cell lines in vitro and in vivo. RESULTS: We identified SPINT2 as a candidate tumor-suppressor gene within a group of CpG islands (designated GT-CMG) that are hypermethylated in both IDH1MUT and IDH1WT gliomas but not in normal brain. We established that SPINT2 downregulation results from promoter hypermethylation, and that restoration of SPINT2 expression reduces c-Met activation and tumorigenic properties of GBM cells. CONCLUSIONS: We defined a previously under-recognized group of coordinately methylated CpG islands common to both IDH1WT and IDH1MUT gliomas (GT-CMG). Within GT-CMG, we identified SPINT2 as a top cancer-related candidate and demonstrated that SPINT2 suppressed GBM via down-regulation of c-Met activation.

Cyclic Mechanical Stretch Induced Smooth Muscle Cell Changes in Cerebral Aneurysm Progress by Reducing Collagen Type IV and Collagen Type VI Levels.

BACKGROUND/AIMS: Cerebral aneurysm growth is characterized by continuous structural weakness of local smooth muscle cells, though the mechanism is unclear. In this study, we examine protein changes in cerebral aneurysm and human brain vascular smooth muscle cells after cyclic mechanical stretch. We further explore the relationship between the smooth muscle cell changes and reductions in the levels of collagen types IV and VI. METHODS: Saccular cerebral aneurysms (n=10) were collected, and temporal artery samples were used as controls. Quantitative proteomics were analyzed and histopathological changes were examined. Smooth muscle cells were cultured in a flexible silicone chamber and subjected to 15% cyclic mechanical stretch. The effect of stretch on the cell viability, function, gene and protein expression were further studied for the understanding the molecular mechanism of aneurysm development. RESULTS: Proteomics analysis revealed 92 proteins with increased expression and 88 proteins with decreased expression compared to the controls (p<0.05). KEGG pathway analysis showed that the change in focal adhesion and extracellular matrix-receptor interaction, suggesting the involvement of collagen type IV and VI. The aneurysm tissue exhibited fewer smooth muscle cells and lower levels of collagen type IV and VI. Human brain vascular smooth muscle cell culture showed spindle-like cells and obvious smooth muscle cell layer. Cell proteomics analysis showed that decreased expression of 118 proteins and increased expression of 32 proteins in smooth muscle cells after cyclic mechanical stretch. KEGG pathway analysis indicated that focal adhesion and ECM-receptor interaction were involved. After cyclic mechanical stretch, collagen type IV and IV expression were decreased. Moreover, the stretch induced MMP-1 and MMP-3 expression elevation. CONCLUSION: We demonstrated that collagen type IV and VI were decreased in cerebral aneurysms and continuous cyclic mechanical stretch induced smooth muscle cell changes. Smooth muscle cell protection provides an additional therapeutic option to prevent the growth of cerebral aneurysms.

Alpha-interferon suppresses hepadnavirus transcription by altering epigenetic modification of cccDNA minichromosomes.

Covalently closed circular DNA (cccDNA) of hepadnaviruses exists as an episomal minichromosome in the nucleus of infected hepatocyte and serves as the transcriptional template for viral mRNA synthesis. Elimination of cccDNA is the prerequisite for either a therapeutic cure or immunological resolution of HBV infection. Although accumulating evidence suggests that inflammatory cytokines-mediated cure of virally infected hepatocytes does occur and plays an essential role in the resolution of an acute HBV infection, the molecular mechanism by which the cytokines eliminate cccDNA and/or suppress its transcription remains elusive. This is largely due to the lack of convenient cell culture systems supporting efficient HBV infection and cccDNA formation to allow detailed molecular analyses. In this study, we took the advantage of a chicken hepatoma cell line that supports tetracycline-inducible duck hepatitis B virus (DHBV) replication and established an experimental condition mimicking the virally infected hepatocytes in which DHBV pregenomic (pg) RNA transcription and DNA replication are solely dependent on cccDNA. This cell culture system allowed us to demonstrate that cccDNA transcription required histone deacetylase activity and IFN-α induced a profound and long-lasting suppression of cccDNA transcription, which required protein synthesis and was associated with the reduction of acetylated histone H3 lysine 9 (H3K9) and 27 (H3K27) in cccDNA minichromosomes. Moreover, IFN-α treatment also induced a delayed response that appeared to accelerate the decay of cccDNA. Our studies have thus shed light on the molecular mechanism by which IFN-α noncytolytically controls hepadnavirus infection.

C-terminally truncated form of αB-crystallin is associated with IDH1 R132H mutation in anaplastic astrocytoma.

Malignant gliomas are the most common human primary brain tumors. Point mutation of amino acid arginine 132 to histidine (R132H) in the IDH1 protein leads to an enzymatic gain-of-function and is thought to promote gliomagenesis. Little is known about the downstream effects of the IDH1 mutation on protein expression and how and whether changes in protein expression are involved in tumor formation or propagation. In the current study, we used 2D DIGE (difference gel electrophoresis) and mass spectrometry to analyze differences in protein expression between IDH1(R132H) mutant and wild type anaplastic (grade III) astrocytoma from human brain cancer tissues. We show that expression levels of many proteins are altered in IDH1(R132H) mutant anaplastic astrocytoma. Some of the most over-expressed proteins in the mutants include several forms of αB-crystallin, a small heat-shock and anti-apoptotic protein. αB-crystallin proteins are elevated up to 22-fold in IDH1(R132H) mutant tumors, and αB-crystallin expression appears to be controlled at the post-translational level. We identified the most abundant form of αB-crystallin as a low molecular weight species that is C-terminally truncated. We also found that overexpression of αB-crystallin can be induced by transfecting U251 human glioblastoma cell lines with the IDH1(R132H) mutation. In conclusion, the association of a C-terminally truncated form of αB-crystallin protein with the IDH1(R132H) mutation is a novel finding that could impact apoptosis and stress response in IDH1 mutant glioma.