Seasonal dynamics response mechanism of benthic microbial community to artificial reef habitats.

Artificial reefs (ARs) have been globally deployed to enhance and restore coastal resource and ecosystems. Microorganisms play an essential role in marine ecosystems, while the knowledge regarding the impact of ARs on microecology is still limited, particularly data concerning the response of benthic microbial community to AR habitats. In this study, the seasonal dynamics of benthic microbial community in AR and adjacent non-artificial reef (NAR) areas surrounding Xiaoshi Island were investigated with high-throughput sequencing technology. The results revealed that the diversity and structure of microbial community between AR and NAR both displayed pronounced seasonal dynamics. There was a greater influence of season factors on microbial communities than that of habitat type. The microbial communities in AR and NAR habitats were characterized by a limited number of abundant taxa (ranging from 5 to 12 ASVs) with high relative abundance (8.35-25.53%) and numerous rare taxa (from 5994 to 12412 ASVs) with low relative abundance (11.91%-24.91%). Proteobacteria, Bacteroidota and Desulfobacterota were the common predominant phyla, with the relative abundances ranging from 50.94% to 76.76%. A total of 52 biomarkers were discovered, with 15, 4, 6, and 27 biomarkers identified in spring, summer, autumn and winter, respectively. Co-occurrence network analysis indicated that AR displayed a more complex interaction pattern and higher susceptibility to external disturbances. Furthermore, the neutral model and ßNTI analyses revealed that the assembly of microbial communities in both AR and NAR is significantly influenced by stochastic processes. This study could provide valuable insights into the impact of ARs construction on the benthic ecosystems and would greatly facilitate the development and implementation of the future AR projects.

Lanthanum nitrate demonstrated no genotoxicity in the conducted tests.

Given the widespread applications in industrial and agricultural production, the health effects of rare earth elements (REEs) have garnered public attention, and the genotoxicity of REEs remains unclear. In this study, we evaluated the genetic effects of lanthanum nitrate, a typical representative of REEs, with guideline-compliant in vivo and in vitro methods. Genotoxicity assays, including the Ames test, comet assay, mice bone marrow erythrocyte micronucleus test, spermatogonial chromosomal aberration test, and sperm malformation assay were conducted to assess mutagenicity, chromosomal damage, DNA damage, and sperm malformation. In the Ames test, no statistically significant increase in bacterial reverse mutation frequencies was found as compared with the negative control. Mice exposed to lanthanum nitrate did not exhibit a statistically significant increase in bone marrow erythrocyte micronucleus frequencies, spermatogonial chromosomal aberration frequencies, or sperm malformation frequencies compared to the negative control (P > 0.05). Additionally, after a 24-h treatment with lanthanum nitrate at concentrations of 1.25, 5, and 20 µg/ml, no cytotoxicity was observed in CHL cells. Furthermore, the comet assay results indicate no significant DNA damage was observed even after exposure to high doses of lanthanum nitrate (20 µg/ml). In conclusion, our findings suggest that lanthanum nitrate does not exhibit genotoxicity.

Experimental investigation on the aero-optical effects of supersonic gas films with various cooling fluids.

Despite the fact that a supersonic cooling gas film can efficiently insulate aerodynamic heating, its interaction with the mainstream generates a sophisticated flow structure which may cause significant aero-optical ramifications. This study aims to analyze the fluid structure and wavefront distortion of supersonic gas film when subjected to varying nozzle pressure ratios (NPR) by employing two distinct cooling refrigerants, namely C O 2 and air. Within the NPR range of 0 to 2, a linear relationship exists between the wavefront distortion of both C O 2 and air films, while the C O 2 film exhibits higher wavefront distortion than the air. Additionally, the influence of condensation on the discrepancies in aero-optical effects of the two refrigerants is discussed.

Nitrogen removal performance of aerobic denitrifying bacteria enhanced by an iron-anode pulsed electric field.

Pulsed electric field (PEF) technology has attracted considerable attention because it can efficiently treat pollutants that are difficult to degrade. In this study, a PEF system using iron as the electrode was constructed to investigate the effect of PEF-Fe on the growth and metabolism of aerobic denitrifying bacteria and the effectiveness of wastewater nitrogen removal. The chemical oxygen demand, NO3--N and nitrate removal rates were 98.93%, 97.60% and 24.40 mg·L-1·h-1, respectively, under optimal conditions. As confirmed in this study, PEF-Fe could improve the key enzyme activities of W207-14. Scanning electron microscopy revealed that the surface of PEF-Fe-treated W207-14 was intact and smooth without any irreversible deformation. Flow cytometry combined with fluorescence staining analysis also confirmed reversible electroporation on the cell membrane surface of PEF-Fe-treated W207-14. Differentially expressed gene enrichment analysis showed that PEF-Fe activated the transmembrane transport function of ATP-binding cassette transporte (ABC) transport proteins and enhanced the cell membrane permeability of aerobic denitrifying bacteria. The significant differential expression of iron-sulphur cluster proteins facilitated the regulation of electron transport and maintenance of the dynamic balance of iron ions within the PEF-Fe system.

The predictive value of preoperative paraspinal muscle morphometry on complications after lumbar surgery: a systematic review.

PURPOSE: The effect of paraspinal muscles atrophy and fat infiltration (FI) on the complications of spinal surgery has not been established. METHODS: A review of the literature was conducted from a search of the PubMed, EMBASE, and Web of Science databases from inception through January 2021. The literature was searched and assessed by independent reviewers based on criteria that included an assessment of preoperative paraspinal muscle morphology in addition to measuring its relationship to surgical complications. All relevant papers were assessed for risk of bias according to the modified Newcastle Ottawa Scale and the Joanna Briggs Institute Critical Appraisal Tools. A narrative synthesis was conducted. RESULTS: The initial search yielded 5632 studies, of which 16 studies were included in the analysis. All included studies were at a low risk of bias. There existed strong evidence that the atrophy and FI of paraspinal muscles had an association with the development of bone nonunion (two high quality studies), pedicle screw loosening (two high quality studies), adjacent segment degeneration (three high quality studies) and proximal junctional kyphosis (five high quality studies) after lumbar surgery. Besides, there is also limited evidence for association between atrophy and FI of paraspinal extensor muscles and less local and global curve improvement. CONCLUSIONS: Strong evidence was found for an association between preoperative paraspinal muscle degeneration and multiple postoperative complications after lumbar surgery. However, the findings should be interpreted with caution due to the small quantity of the available literature and high heterogeneity among studies.

Molecular characterization, expression, and function of Vitellogenin genes in Phytoseiulus persimilis.

Vitellogenin (Vg) is an important factor that impacts oocyte maturation, egg formation and embryonic development in Arthropoda. Two orthologs of Vg gene were obtained from the genome of Phytoseiulus persimilis and termed as PpVg1 and PpVg2. Both orthologs belong to the large lipid transfer protein superfamily. The expression of PpVg1 and PpVg2 was low in immatures and male adults, and increased rapidly in female adults after mating, and reached a peak before the first egg was laid (168×  and 20.5×  the level in virgin females, respectively). When PpVg1 and PpVg2 were interfered with dsRNA, the relative expression decreased by 81.0 and 30.9%, respectively, and 7.8 and 31.4% interfered individuals died within 24 h. Among surviving individuals, ca. 51.1 and 44.8% are infertile. Factors that might be related to expression of Vg genes are also discussed.

Eicosapentaenoic acid ameliorates pulmonary hypertension via inhibition of tyrosine kinase Fyn.

Pulmonary arterial hypertension (PAH) is a multifactorial disease characterized by pulmonary arterial vasoconstriction and remodeling. Src family tyrosine kinases, including Fyn, play critical roles in vascular remodeling via the inhibition of STAT3 signaling. EPA is known to inhibit Fyn kinase activity. This study investigated the therapeutic potential and underlying mechanisms of EPA and its metabolite, resolvin E1 (RvE1), to treat PAH using monocrotaline-induced PAH model rats (MCT-PAH), human pulmonary artery endothelial cells (HPAECs), and human pulmonary artery smooth muscle cells (HPASMCs). Administration of EPA 1 and 2 weeks after MCT injection both ameliorated right ventricular hypertrophy, remodeling and dysfunction, and medial wall thickening of the pulmonary arteries and prolonged survival in MCT-PAH rats. EPA attenuated the enhanced contractile response to 5-hydroxytryptamine in isolated pulmonary arteries of MCT-PAH rats. Mechanistically, the treatment with EPA and RvE1 or the introduction of dominant-negative Fyn prevented TGF-ß2-induced endothelial-to-mesenchymal transition and IL-6-induced phosphorylation of STAT3 in cultured HPAECs. EPA and RvE1 suppressed Src family kinases' activity as evaluated by their phosphorylation status in cultured HPAECs and HPASMCs. EPA and RvE1 suppressed vasocontraction of rat and human PA. Furthermore, EPA and RvE1 inhibited the enhanced proliferation and activity of Src family kinases in HPASMCs derived from patients with idiopathic PAH. EPA ameliorated PAH's pathophysiology by mitigating vascular remodeling and vasoconstriction, probably inhibiting Src family kinases, especially Fyn. Thus, EPA is considered a potent therapeutic agent for the treatment of PAH.

[Study on improvement provided by water extracts of Polygoni Multiflori Radix and Polygoni Multiflori Radix Praeparata on non-alcoholic steatohepatitis in mice induced by MCD].

This study aims to observe the improvement of non-alcoholic steatohepatitis(NASH) after using water extracts of Polygoni Multiflori Radix and Polygoni Multiflori Radix Praeparata and explore their preliminary mechanism. Mice were fed with methionine-choline-deficent diet(MCD) for 6 weeks for modeling, and mice were orally given with 50, 100, 200 mg·kg~(-1) of Polygoni Multiflori Radix water extract(PMRWE) or Polygoni Multiflori Radix Praeparata water extract(PMRPWE) at the last 4 weeks. During the whole experimental procedure, the body weight changes of the mice were monitored and recorded. Serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST) activities were detected; liver histopathological evaluation and NAFLD activity score(NAS) calculation were conducted, and the levels of reactive oxygen species(ROS) in liver tissues were analyzed. The contents of triglyceride(TG) and non-esterified fatty acids(NEFA) in liver tissues were detected, and oil red O staining of the liver tissues was conducted and observed. Quantitative polymerase chain reaction(qPCR) was used to detect hepatic mRNA expression of ß-oxidation-related genes in mice. The results showed that PMRWE(100, 200 mg·kg~(-1)) and PMRPWE(50, 100, 200 mg·kg~(-1)) alleviated liver damage in MCD-induced NASH in mice. PMRWE(100, 200 mg·kg~(-1)) and PMRPWE(50, 100, 200 mg·kg~(-1)) reduced hepatic li-pid accumulation in mice with NASH. Different doses of PMRPWE inversed the decreased hepatic mRNA expression of ß-oxidation-related genes in mice with NASH. This study indicated that PMRPWE and PMRWE could ameliorate MCD-induced NASH in mice by promoting fatty acid ß oxidation, reducing liver lipid accumulation, and alleviating liver damage. Moreover, the protective effect of PMRPWE against MCD-induced NASH was better than PMRWE.

[Differences in spatial distribution of medicinal plant resources in Yinshan region of Inner Mongolia].

Yinshan Mountains stands on the southern edge of the Inner Mongolia Plateau, which stretches 1 200 km from east to west and 50 to 100 km from north to south. The rich and varied topographic environment of the Yinshan Mountains has created a variety of vegetation floras, which also makes the species of medicinal plant resources in this area unevenly distributed. Therefore, studying the spatial distribution difference of medicinal plant resources among various banners, counties, and districts in the Yinshan area is of great significance to formulate the protection policy and promote the industry development of medicinal plant. This study is based on the fourth national survey of traditional Chinese medicine resources in Inner Mongolia, regarding the results of the third national survey of traditional Chinese medicine resources. The species of medicinal plant resources in the Yinshan area around 31 banners, counties and districts were counted in detail. Then, using exploratory spatial data analysis(ESDA), trend surface analysis, spatial autocorrelation, geographical detector and other geostatistical analysis methods to analyze the differences in the spatial distribution of medicinal plant resources of the Yinshan area in Inner Mongolia. After discussing and analyzing the experimental results to account for the reasons for the overall trend of change and the degree of aggregation, the author further put forward relevant constructive suggestions. The results show that the areas with the most abundant and concentrated distribution of medicinal plant resources in the Yinshan area are located in Guyang county, Shiguai District of Baotou city, Tutou right banner, and Tuoketuo county; the higher richness and concentrated distribution of medicinal plant resources is in Wulate front banner, Wulate middle banner, Wulate back banner; areas with relatively low abundance and concentrated distribution of medicinal plant resources located in Qingshan district of Baotou city, Saihan district and Yuquan district of Hohhot city; areas with the lowest abundance and concentrated distribution of medicinal plant resources are located in Xincheng district and Huimin district of Hohhot city. It can be concluded that the horizontal distribution difference of multiple ecological factors, the special wetland environment of the river, the vertical difference of elevation, the farmland and other factors have an important influence on the richness of the medicinal plant resources species.

MBD1 promotes the malignant behavior of gallbladder cancer cells and induces chemotherapeutic resistance to gemcitabine.

BACKGROUND: Methyl-CpG binding domain protein 1 (MBD1), which couples DNA methylation to transcriptional repression, has been implicated in transcriptional regulation, heterochromatin formation, genomic stability, cell cycle progression and development. It has also been proven that MBD1 is involved in tumor development and progression. However, whether MBD1 is involved in tumorigenesis, especially in gallbladder cancer, is totally unknown. METHODS: Human GBC-SD and SGC996 cells were used to perform experiments. Invasion, wound healing and colony formation assays were performed to evaluate cell viability. A CCK-8 assay was performed to assess gallbladder cancer cell viability after gemcitabine treatment. Western blot analysis was used to evaluate changes in protein expression. Human gallbladder cancer tissues and adjacent nontumor tissues were subjected to immunohistochemical staining to detect protein expression. RESULTS: We found that MBD1 expression was significantly upregulated in gallbladder cancer tissues compared with that in surrounding normal tissues according to immunohistochemical analysis of 84 surgically resected gallbladder cancer specimens. These data also indicated that higher MBD1 expression was correlated with lymph node metastasis and poor survival in gallbladder cancer patients. Overexpression and deletion in vitro validated MBD1 as a potent oncogene promoting malignant behaviors in gallbladder cancer cells, including invasion, proliferation and migration, as well as epithelial-mesenchymal transition. Studies have demonstrated that epithelial-mesenchymal transition is common in gallbladder cancer, and it is well known that drug resistance and epithelial-mesenchymal transition are very closely correlated. Herein, our data show that targeting MBD1 restored gallbladder cancer cell sensitivity to gemcitabine chemotherapy. CONCLUSIONS: Taken together, the results of our study revealed a novel function of MBD1 in gallbladder cancer tumor development and progression through participation in the gallbladder cancer epithelial-mesenchymal transition program, which is involved in resistance to gemcitabine chemotherapy. Thus, MBD1 may be a potential therapeutic target for gallbladder cancer.

Specific recognition of ribavirin in animal-derived foods by high performance liquid chromatography combined with magnetic solid-phase extraction based on highly selective Zr-Fe3 O4.

For the first time, a magnetic solid-phase extraction with high-performance liquid chromatography detection method using Zr functionalized Fe3 O4 magnetic material to enrich ribavirin was successfully established. Zr components that modified in Fe3 O4 nanoparticles via a simple one-step hydrothermal method was selected in this work to specifically capture ribavirin by the strong chemical bonding between Zr components of Zr functionalized Fe3 O4 magnetic material and cis-hydroxyl of ribavirin, which was confirmed by pseudo-second-order kinetic model. And Fe3 O4 components were selected in this work to achieve simple operation. Under the optimal experimental conditions, proposed magnetic solid-phase extraction with high-performance liquid chromatography detection method along with Zr functionalized Fe3 O4 magnetic material offered a wide range linearity at 10-200 µg/L with correlation coefficient of 0.9978 with low detection limit of 2.68 µg/L for ribavirin. The relative standard deviations obtained from nine parallel extractions of 100 µg/L ribavirin were 4.41% and revealed good repeatability. This established method was successfully applied to detect real samples including chicken liver, egg, and shrimp with satisfactory recoveries of 74.13-92.9%.

Sodium pheophorbide a has photoactivated fungicidal activity against Pestalotiopsis neglecta.

Sodium pheophorbide a (SPA) is a natural photosensitizer. To explore its antifungal activity and mechanism, we studied its inhibitory effects on spore germination and mycelial growth of Pestalotiopsis neglecta. We used sorbitol, 2-thiobarbituric acid (TBA) and electron microscopy to determine its effects on cell wall integrity, cell membrane lipid peroxidation and mycelial morphology. Finally, the effects of SPA on enzyme activity in mycelia were determined. The results showed that SPA effectively inhibited spore germination and mycelial growth of P. neglecta under light conditions (4000 lx, 24 h). Scanning electron microscopy (SEM) revealed that SPA treatment resulted in a roughened, twisted and knotted mycelial surface and abnormal mycelial growth. SPA influenced cell wall integrity, and the content of MDA, a cell membrane lipid peroxidation product was significantly increased (P < 0.05). SPA also significantly inhibited SOD, POD and PG activity, but enhanced PPO activity (P < 0.05). In conclusion, SPA may have potential to become a biological pesticide.

Evaluation of the genetic parameters and mutation analysis of 22 STR loci in the central Chinese Han population.

At present, the Han nationality is China's main ethnic group and also the most populous nation in the world. This is a great resource to study microsatellite mutations and for the study of ethnogeny. The aim of this study is to investigate the genetic polymorphisms and mutations of 22 autosomal STR loci in 2475 individuals from Henan province, China. DNA is amplified and genotyped using PowerPlex™24 system. The gene frequencies, forensic parameters, and the mutation rate of the 22 STR loci are analyzed. A total of 295 alleles are observed in this Henan Han population, and the allelic frequencies ranged from 0.0003 to 0.5036. In order to investigate the genetic relationships between the Henan Han and the other 14 different populations, our present data were compared with previously published data for the same 15 STR loci. The results indicated that the Henan Han had closer genetic relationships the groups including Minnan Han, Maonan, Yi and Guangdong Han groups while the South morocco population, the Moroccan population, the Malay group, and the Uigur stand away from Henan Han. Except of D2S441, D13S317, PentaE, D2S1338, D5S818, TPOX and D19S433, the mutation events are found in the other 15 STR loci. A total of 40 mutation events are observed in the 15 STR loci. The mutation rates are ranged from 0 to 4.85 × 10-3. In this study, 39 mutations are single-step mutations, and only one at FGA comprised two steps. STR mutation is commonly existed in paternity testing, while there are no STR mutation studies of the 22 STR loci in the Henan Han population. It is of great importance in forensic individual discrimination and paternal testing.

Fluid shear stress suppresses TNF-α-induced apoptosis in MC3T3-E1 cells: Involvement of ERK5-AKT-FoxO3a-Bim/FasL signaling pathways.

TNF-α is known to induce osteoblasts apoptosis, whereas mechanical stimulation has been shown to enhance osteoblast survival. In the present study, we found that mechanical stimulation in the form of fluid shear stress (FSS) suppresses TNF-α induced apoptosis in MC3T3-E1 cells. Extracellular signal-regulated kinase 5 (ERK5) is a member of the mitogen-activated protein kinase (MAPK) family that has been implicated in cell survival. We also demonstrated that FSS imposed by flow chamber in vitro leads to a markedly activation of ERK5, which was shown to be protective against TNF-α-induced apoptosis, whereas the transfection of siRNA against ERK5 (ERK5-siRNA) reversed the FSS-medicated anti-apoptotic effects. An initial FSS-mediated activation of ERK5 that phosphorylates AKT to increase its activity, and a following forkhead box O 3a (FoxO3a) was phosphorylated by activated AKT. Phosphorylated FoxO3a is sequestered in the cytoplasm, and prevents it from translocating to nucleus where it can increase the expression of FasL and Bim. The inhibition of AKT-FoxO3a signalings by a PI3K (PI3-kinase)/AKT inhibitor (LY294002) or the transfection of ERK5-siRNA led to the nuclear translocation of non-phosphorylated FoxO3a, and increased the protein expression of FasL and Bim. In addition, the activation of caspase-3 by TNF-α was significantly inhibited by aforementioned FSS-medicated mechanisms. In brief, the activation of ERK5-AKT-FoxO3a signaling pathways by FSS resulted in a decreased expression of FasL and Bim and an inhibition of caspase-3 activation, which exerts a protective effect that prevents osteoblasts from apoptosis.

Pitfalls of diagnosing urinary tract infection in infants and young children.

BACKGROUND: The aim of this study was to examine the sensitivity and specificity of pyuria-based diagnosis of urinary tract infection (UTI) in urine collected by transurethral catheterization, and the reliability of diagnosis of pyuria in urine collected in a perineal bag. The gold standard for UTI diagnosis is significant colony counts of a single organism in urine obtained in a sterile manner. METHODS: We enrolled 301 patients who underwent medical examination at the present hospital for possible UTI between January 2005 and December 2009. We collected 438 urine samples by transurethral catheterization. We investigated the accuracy of pyuria-based diagnosis of UTI using transurethral catheterization urine specimens, and the reliability of diagnosis of pyuria using bag-collected urine specimens. RESULTS: The false-negative rate of UTI diagnosis based on pyuria in transurethral catheterization urine sediments was 9.0%; there was no significant difference in the false-negative rate of UTI diagnosis between boys and girls. Approximately 28% of pyuria-positive bag-collected urine specimens were pyuria negative on transurethral catheterization; this rate was significantly higher in girls than in boys (56.7% vs. 8.9%, P < 0.0001). CONCLUSIONS: The absence of pyuria in transurethral catheterization urine sediments does not rule out UTI. Pyuria in bag-collected urine specimens frequently consists of urine leukocytes from external genitalia as well as from the urinary tract.

The excitation mechanism of btp2 Ir(acac) in CBP host.

Whether bis(2-(2'-benzo[4,5-α]thienyl)pyridinato-N,C3')iridium(acetylacetonate) (btp2 Ir(acac)) emission comes from carrier trapping and/or energy transfer, when doped in the 4,4'-bis(N-carbazolyl)biphenyl (CBP) host in organic light-emitting devices, is not clear; therefore, the btp2 Ir(acac) emission in CBP hosts was studied. In the red-doped device, both N,N'-bis(1-naphthyl)-N,N'-diphenyl-1.1'-bipheny1-4-4'-diamine (NPB) and (1,1'-biphenyl-4'-oxy)bis(8-hydroxy-2-methylquinolinato)-aluminum (BAlq) emission appeared, which illustrated that CBP excitons cannot be formed at two emissive layer (EML) interfaces in the device. In the co-doped devices, NPB and BAlq emissions disappear and 1,4-bis[2-(3-N-ethylcarbazoryl)vinyl]benzene (BCzVB) emission appears, illustrating the formation of CBP excitons at two EML interfaces in these devices. The reason for this difference was analyzed and it was found that holes in the NPB layer could be made directly into the CBP host in the EML interface of the red-doped device. In contrast, holes were injected into CBP host via the btp2 Ir(acac)/BCzVB dopants in the co-doped devices, which facilitated hole injection from the NPB layer to the EML, leading to the formation of CBP excitons at two EML interfaces in the co-doped devices. Therefore, btp2 Ir(acac) emission was caused by carrier trapping in the red-doped device, while, in the co-doped devices, it resulted from both carrier trapping and energy transfer from the CBP. Furthermore, it was revealed that the carrier trapping mechanism is less efficient than the energy transfer mechanism for btp2 Ir(acac) excitation in co-doped devices. In summary, our results clarified the excitation mechanism of btp2 Ir(acac) in the CBP host.

Correlation between insulin-induced estrogen receptor methylation and atherosclerosis.

BACKGROUND: Hyperinsulinemia and insulin resistance have been recently recognized as an important cause of atherosclerosis. Clinical studies have also found that expression of the estrogen receptor is closely related to the incidence of atherosclerosis. This study investigate the effects of insulin and estrogen receptor α (ER-α) in atherosclerosis. METHODS: Double knockout ApoE/Lepr mice were given intraperitoneal injections of insulin, and their aortae were harvested for hematoxylin-eosin staining and immunohistochemical analysis. In addition, vascular smooth muscle cells (VSMCs) were treated with insulin or infected with a lentivirus encoding exogenous ER-α, and changes in gene expression were detected by real-time polymerase chain reaction and western blotting. The methylation levels of the ER-α gene were tested using bisulfite sequencing PCR, and flow cytometry and EdU assay were used to measure VSMCs proliferation. RESULTS: Our results showed that insulin can induce the formation of atherosclerosis. Gene expression analysis revealed that insulin promotes the expression of DNA methyltransferases and inhibits ER-α expression, while 5-aza-2'-deoxycytidine can inhibit this effect of insulin. Bisulfite sequencing PCR analysis showed that methylation of the ER-α second exon region increased in VSMCs treated with insulin. The results also showed that ER-α can inhibit VSMCs proliferation. CONCLUSIONS: Our data suggest that insulin promotes the expression of DNA methyltransferases, induces methylation of ER-α second exon region and decreases the expression of ER-α, thereby interfering with estrogen regulation of VSMCs proliferation, resulting in atherosclerosis.

Fluid shear stress promotes osteoblast proliferation via the Gαq-ERK5 signaling pathway.

Fluid shear stress (FSS) is a ubiquitous mechanical stimulus that potently promotes osteoblast proliferation. Previously, we reported that extracellular signal-regulated kinase 5 (ERK5) is essential for FSS-induced osteoblast proliferation. However, the precise mechanism by which FSS promotes osteoblast proliferation via ERK5 activation is poorly understood. The aim of this study was to determine the critical role of Gαq in FSS-induced ERK5 phosphorylation and osteoblast proliferation, as well as the downstream targets of the Gαq-ERK5 pathway. MC3T3-E1 cells were transfected with 50 nM Gαq siRNA, treated with 5 mM XMD8-92 (a highly selective inhibitor of ERK5 activity), and/or exposed to FSS (12 dyn/cm(2)). Cell proliferation was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The protein expression levels of Gαq, P-ERK5, ERK5, Cyclin B1, and CDK1 were analyzed by Western blot. Physiological FSS exposure for 60 min remarkably promoted MC3T3-E1 cell proliferation, however, this effect was suppressed by siRNA-mediated Gαq knockdown or inhibition of ERK5 activity by XMD8-92 treatment, suggesting that Gαq and ERK5 might modulate FSS-increased osteoblast proliferation. Furthermore, ERK5 phosphorylation was dramatically inhibited by Gαq siRNA. In addition, our study further revealed that FSS treatment of MC3T3-E1 cells for 60 min markedly upregulated the protein expression levels of Cyclin B1 and CDK1, and this increased expression was predominantly blocked by Gαq siRNA or XMD8-92 treatment. We propose that FSS acts on the Gαq-ERK5 signaling pathway to upregulate Cyclin B1 and CDK1 expression, thereby resulting in MC3T3-E1 cell proliferation. Thus, the Gαq-ERK5 signaling pathway may provide useful information regarding the treatment of bone metabolic disease.

A case of acute myocardial infarction after successful transcatheter closure of ventricular septal defect.

Congenital heart diseases can be treated without surgery through advances in interventional cardiology. Complications such as infection and thrombus formation may develop due to foreign materials used during these procedures. Paradoxical embolism is a rare complication of transcatheter closure of ventricular septal defect (VSD) and could be responsible for acute myocardial infarction. Herein, we present a case of coronary thrombosis in a 2-year-old patient with VSD, which was closed with the Amplatzer VSD device. Although extremely rare, it should be considered in the appropriate clinical setting.