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Objective: To explore the expression and the role of chemerin in idiopathic pulmonary fibrosis (IPF). Methods: Quantitative PCR and Western blotting were used to determine the mRNA and protein levels of chemerin in lung tissues from IPF patients and the controls. Clinical serum level of chemerin was analyzed by enzyme-linked immunosorbent assay. The mouse lung fibroblasts isolated and cultured in vitro were divided into the control, TGF-ß, TGF-ß+chemerin and chemerin groups. Immunofluorescence staining was used to observe the expression of α-smooth muscle actin (α-SMA). C57BL/6 mice were randomly divided into the control, bleomycin, bleomycin+chemerin, and chemerin groups. Masson and immunohistochemical staining were performed to evaluate the severity of pulmonary fibrosis. Expression of epithelial to mesenchymal transition (EMT) markers was detected by quantitative PCR and immunohistochemical staining in the in vitro and in vivo models of pulmonary fibrosis, respectively. Results: Compared with the control group, the expression of chemerin was downregulated in both the lung tissue and the serum of IPF patients. Immunofluorescence showed that treatment of fibroblasts with TGF-ß alone resulted in a robust expression of α-SMA, whereas treatment with TGF-ß and chemerin together exhibited the similar expression levels of α-SMA as the control group. Masson staining indicated that the bleomycin-induced pulmonary fibrosis model was constructed successfully, while treatment of chemerin partially alleviated the damage of lung tissue. Immunohistochemical staining showed that the expression of chemerin in the lung tissue was significantly decreased in the bleomycin group. Quantitative PCR and immunohistochemistry showed that chemerin attenuated EMT induced by TGF-ß and bleomycin both in vitro and in vivo. Conclusions: The expression of chemerin was reduced in patients with IPF. Chemerin may play a protective role in the development of IPF by regulating EMT, providing a new idea for the clinical treatment of IPF.
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Transição Epitelial-Mesenquimal , Fibrose Pulmonar Idiopática , Camundongos , Animais , Camundongos Endogâmicos C57BL , Pulmão , Fibrose Pulmonar Idiopática/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Bleomicina/metabolismo , Bleomicina/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Quimiocinas/metabolismo , Quimiocinas/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologiaRESUMO
Objective: To investigate the effect of bilateral superior cervical ganglionectomy on cardiac remodeling and function in pressure-overloaded heart failure (HF) mice. Methods: Pressure-overloaded HF mouse model was produced by severe thoracic aorta banding (sTAB). Bilateral superior cervical ganglionectomy (SCGx) was performed 2 weeks after sTAB. Twenty four 6-week-old male C57BL/6 mice were randomized divided into 4 groups (n=6 each): control group: sham sTAB+sham SCGx; denervated group: sham sTAB+SCGx; HF group: sTAB+sham SCGx; denervated HF group: sTAB+SCGx. Cardiac function was measured by echocardiography at week 0, 1, 2, and 4 after sTAB, respectively. All mice were sacrificed at the end of week 4 and heart tissues were harvested. HE and Masson staining were performed. Immunohistochemical staining (IHC) for tyrosine hydroxylase (TH), adrenergic receptor ß1 (AR-ß1) and CD68 was performed. Western blot was used to determine the protein expression level of TH, B type natriuretic peptide (BNP), and AR-ß1. Results: Left ventricular ejection fraction (LVEF) declined continuously in HF group. LVEF was similar between denervated HF group and control group at various time points (P>0.05). LVEF was significantly higher in denervated HF group than in HF group at the end of week 4 (P<0.05). HE staining showed that cross sectional cardiomyocyte area was significantly larger in HF group than in control group and denervated HF group (P<0.05), which was similar between denervated HF group and control group (P>0.05). Masson staining showed that fibrosis level was significantly lower in denervated HF group than in HF group (P<0.05). IHC showed that TH+nerves and CD68+ macrophages were significantly increased in HF mice as compared to control mice (P<0.05), whereas this change was abolished in denervated HF group. AR-ß1 was significantly down-regulated in HF group compared with control group (P<0.05), which was not affected by denervation (P>0.05). Western blot demonstrated that the expression level of TH and BNP was significantly higher in HF group compared with the control group (P<0.05), whereas this difference was diminished in denervated HF group (P>0.05). Conclusion: Bilateral superior cervical ganglionectomy can reduce sympathetic innervation and macrophage infiltration in pressure overloaded failure heart, thus attenuate cardiac remodeling and improve cardiac function.
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Ganglionectomia , Insuficiência Cardíaca , Animais , Estudos Transversais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Volume Sistólico , Função Ventricular Esquerda , Remodelação VentricularRESUMO
Objective: To investigate cytomegalovirus detoxification and associated factors among preschool children in Yinan County, Shandong Province. Methods: Two kindergartens were selected from the county and township of Yinan respectively. A total of 250 children were investigated in October 2018. Case information was obtained through the child's guardian. Saliva samples of children and their mothers were collected for cytomegalovirus realtime-PCR detection.The status of CMV detoxification of children was explored and the associated factors were analyzed. Results: A total of 242 preschool children were investigated, and the detoxification rate of cytomegalovirus among them was 22.31% (54/242, 95%CI: 17.0%-27.6%). Logistic regression analysis showed that the rate of detoxification was higher in children whose mothers were cytomegalovirus detoxified (OR=12.39, 95%CI:1.73-88.65)and whose school was located in the county (OR=3.58, 95%CI:1.34-9.55). Conclusions: The detoxification rate of cytomegalovirus in preschool children is high, and there is mutual transmission between children and mothers. Women of childbearing age should pay attention to prevent congenital cytomegalovirus infection when they come into contact with children.
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Infecções por Citomegalovirus , Citomegalovirus , Pré-Escolar , Citomegalovirus/genética , Infecções por Citomegalovirus/epidemiologia , Feminino , Humanos , Lactente , Mães , Reação em Cadeia da Polimerase em Tempo Real , SalivaRESUMO
The flicker noise of source follower transistors is the dominant noise source in image sensors. This paper reports a systematic study of the shallow trench isolation effect in transistors with different sizes under high temperature conditions that correspond to the quantity of empty defect sites. The effects of shallow trench isolation sidewall defects on flicker noise characteristics are investigated. In addition, the low-frequency noise and subthreshold swing degrade simultaneously in accordance to the device gate width scaling. Both serious subthreshold leakage and considerable noise can be attributed to the high trap density near the STI edge. Consequently, we propose a coincidental relationship between the noise level and the subthreshold characteristic; its trend is identical to the experiments and simulation results.
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Bleeding from the lower uterine segment (LUS) during caesarean section remains a life-threatening obstetric problem, particularly in women with placenta praevia or partial placenta accreta in the LUS. Various conservative measures for the surgical treatment of postpartum haemorrhage have been studied for decades. In this paper we describe a funnel compression suture to staunch intractable bleeding from LUS for placenta praevia accreta. The suture brings the anterior and posterior walls of the LUS together using absorbable thread and was successful in the overwhelming majority of women. It is an easy, safe and effective conservative surgical treatment to stop severe bleeding of the LUS.
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Cesárea/métodos , Placenta Acreta/cirurgia , Placenta Prévia/cirurgia , Hemorragia Pós-Parto/cirurgia , Técnicas de Sutura , Útero/cirurgia , Adulto , Feminino , Humanos , Gravidez , Adulto JovemRESUMO
Genetic factors may play an important role in frozen shoulder etiology, which may involve matrix metalloproteinase-3 (MMP3) gene polymorphisms. In this study, we examined single nucleotide polymorphisms in MMP3 for their association with frozen shoulder susceptibility in a Chinese Han population. The rs591058, rs650108, and rs679620 polymorphisms in the MMP3 gene were genotyped in 112 subjects diagnosed as having frozen shoulder and in 143 healthy controls. rs650108 was found to be significantly associated with an increased risk of frozen shoulder. For other single nucleotide polymorphisms, no statistically significant associations with frozen shoulder were found. In conclusion, our data demonstrated that the MMP3 rs650108 variant was significantly associated with increased frozen shoulder susceptibility in a Chinese Han population.
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Bursite/genética , Metaloproteinase 3 da Matriz/genética , Polimorfismo de Nucleotídeo Único/genética , Povo Asiático , Bursite/epidemiologia , Estudos de Casos e Controles , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Genótipo , Haplótipos/genética , Humanos , Pessoa de Meia-IdadeRESUMO
Previous case-control studies on the relationship between the CYP4F2 gene rs2108622 polymorphism and hypertension have produced contrasting results. In this study, we aimed to further evaluate the relationship between the CYP4F2 gene rs2108622 polymorphism and hypertension. We selected four case-control studies related to the CYP4F2 gene rs2108622 polymorphism and hypertension by searching PubMed, EMBase, the Chinese Biomedical Literature Database, and the Wanfang database. We utilized the Cochran Q-test and the I2 index to measure the heterogeneity across studies. To merge the odds ratio (OR) and the 95% confidence interval (95%CI), we utilized the fixed and random-effect models during the analyses. The present study included 1878 patients with hypertension and 1512 healthy control subjects. By meta-analysis, we did not find any association of the CYP4F2 gene rs2108622 polymorphism with hypertension in either genotype or allele distribution [AA+AG vs GG: OR = 1.18, 95%CI (0.91-1.54), P = 0.21; GG+AG vs AA: OR = 0.91, 95%CI (0.80-1.05), P = 0.20; A allele vs G allele: OR = 1.04, 95%CI (0.93-1.16), P = 0.53]. We concluded that the CYP4F2 gene rs2108622 polymorphism was not associated with hypertension.
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Sistema Enzimático do Citocromo P-450/genética , Predisposição Genética para Doença/genética , Hipertensão/genética , Polimorfismo Genético/genética , Alelos , Povo Asiático/genética , Estudos de Casos e Controles , Família 4 do Citocromo P450 , Frequência do Gene/genética , Genótipo , HumanosRESUMO
Crossing different ploidy grapes is an effective way to obtain new seedless cultivars. Although embryo rescue has been extensively applied in breeding seedless and triploid grapes, only a few improved cultivars have been developed. Based on preliminary studies, we set five crosses between tetraploid and diploid grape varieties to obtain new hybrid triploid germplasms. Additionally, we compared two different methods of performing in vitro embryo rescue and sowing in the development of hybrid triploid grape plants. The results showed that the germination rate of hybrid seeds was much lower (0-22.8%) than that of the self-pollinated seeds (50.9-61.2%) obtained though the same method of in vitro culture. Meanwhile, the seed germination rates of all crosses obtain through in vitro culture (0-61.2%) were higher than those obtained through sowing (0-42.0%). Identification of ploidy level confirmed that three lines obtained from the crosses of 'Ruby Seedless (2x) x Black Olympia (4x)' and 'Big black (2x) x Kyoho (4x)' were triploid, and one line from the cross of 'Big black (2x) x Kyoho (4x)' was haploid, and the others were diploid, tetraploid, or aneuploidy plants. Moreover, 4 haploid and 42 triploid surviving grape seedlings were planted in a vineyard after propagation. Therefore, an efficient system of breeding triploid seedless grapes using embryo rescue was established and 42 hybrid triploid germplasms were obtained for use in future studies.
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Cruzamentos Genéticos , Diploide , Sementes , Vitis/genética , Cruzamento , Quimera , Genótipo , GerminaçãoRESUMO
Octopus minor (Sasaki, 1920) is an economically important cephalopod that is found in the northern coastal waters of China. In this study, we investigated genetic differentiation in fishery populations using amplified fragment length polymorphisms (AFLPs). A total of 150 individuals were collected from five locations: Dalian (DL), Yan-tai (YT), Qingdao (QD), Lianyungang (LY), and Zhoushan (ZS), and 243 reproducible bands were amplified using five AFLP primer combinations. The percentage of polymorphic bands ranged from 53.33 to 76.08%. Nei's genetic identity ranged from 0.9139 to 0.9713, and the genetic distance ranged from 0.0291 to 0.0900. A phylogenetic tree was constructed using the unweighted pair group method with arithmetic mean, based on the genetic distance. The DL and YT populations originated from one clade, while the QD, LY, and ZS populations originated from another. The results indicate that the O. minor stock consisted of two genetic populations with an overall significantly analogous FST value (0.1088, P < 0.05). Most of the variance was within populations. These findings will be important for more sustainable octopus fisheries, so that this marine resource can be conserved for its long-term utilization.
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Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Genética Populacional , Octopodiformes/classificação , Octopodiformes/genética , Polimorfismo Genético , Animais , China , Evolução Molecular , Variação Genética , FilogeniaRESUMO
The Dragon lake diversion channel (DLDC) is the only river that recharges Dragon Lake, an artificial lake in China. This paper examines the main factors influencing water quality by investigating point source and non-point source pollutants along the main route. Based on the complicated system of rivers and desilting basins, a three-dimensional water quality model using environmental fluid dynamics code (EFDC) was developed. The model of DLDC was calibrated and verified using observed data. The error ranges of river water level, total phosphorus, total nitrogen and chemical oxygen demand were within 5%, 10%, 16% and 20%, respectively, all of which meet the precision requirement. The model was employed to predict the concentrations of pollutants in the main stream under current pollution loads within a year and a flood lasting for 24 hours. The results revealed that the main pollution sources that influence the water quality of waterways were the point sources followed by the non-point pollution sources. Water quality improved when large water quantities were delivered and this trend can be described as dilution. The water quality of the Dongfeng main channel meets the requirement; however, the water quality of the Dongfeng River is somewhat poor, and the water quality of the Wei River is seriously contaminated. To address these problems, we suggest that the Dongfeng River and Wei River adopt a culvert under its riverbeds.
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Monitoramento Ambiental/métodos , Lagos/química , Modelos Teóricos , Rios/química , Poluentes Químicos da Água/análise , Análise da Demanda Biológica de Oxigênio , China , Nitrogênio/análise , Fósforo/análise , Qualidade da ÁguaRESUMO
OBJECTIVE: To observe the effectiveness of chlortetracycline (aureomycin) treatment on vulval white lesions and to explore its possible pathogenesis. MATERIALS AND METHODS: From January 2001 to April 2011, 194 patients with vulvar non-neoplastic epithelial disorders were divided into three groups according to therapy regimens received, ie, chlortetracycline treatment group (72 cases), chlortetracycline + beclomethasone treatment group (66 cases), and beclomethasone treatment group (56 cases); their local changes of vulvar lesions were observed and efficacy of these treatment profiles was evaluated after one year. RESULTS: Effective rates of chlortetracycline group, chlortetracycline + clobetasol group and clobetasol groups were 86.1% (62/72), 87.9% (58/66), and 62.5% (35/56), respectively. There was a significant difference among these three groups (Hc = 10.7766,p = 0.0046), the curative rate of clobetasol group was markedly lower than that of the former two groups (p = 0.0072 and p = 0.0019), but was not statistical significant (p = 0.6077) when compared between the former groups. CONCLUSION: The occurrence of vulvar non-neoplastic epithelial disorders may be associated with chlamydia and mycoplasma infection, the chlortetracycline is an effective drug for this illness, the mechanism of which might be related to killing pathogens directly and inhibiting inflammatory mediators.
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Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Clortetraciclina/uso terapêutico , Clobetasol/uso terapêutico , Doenças da Vulva/tratamento farmacológico , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Vulva/etiologia , Adulto JovemRESUMO
Gene duplication is a major evolutionary driving force for establishing new gene functions. However, very little is known about the involvement of the structural divergence of recent duplicated genes in local adaptation. We evaluated the nucleotide variation of recent duplicated pair copies of the hsp17 locus for small heat shock proteins, namely, the older copy hsp17a and the younger copy hsp17b. Forty wild barley (Hordeum spontaneum) genotypes from 7 climatically divergent sites of "Evolution Canyon" I, Mount Carmel, Israel, were investigated for the sequence diversity of their hsp17 copies. We identified single nucleotide polymorphisms (SNPs) of the hsp17 locus and found 150 SNPs of hsp17a and 135 SNPs of hsp17b in the coding region. Total amino acid substitutions were present at 43 positions of hsp17a and 35 positions of hsp17b among the 7 populations. The genetic divergence and haplotype diversity were significantly different among the populations. The diversity was also correlated with microclimatic interslope divergence factors in the canyon. The natural microclimatic selection appears to adaptively diversify the duplicated copies of hsp17 of wild barley between the opposite warmer and cooler slopes, suggesting that the recent duplication of stress-responsive genes were subjected to adaptive evolution. The gene duplication and the resulting functional divergence enable plants to have better fitness in local climate change.
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Duplicação Gênica , Genes de Plantas , Proteínas de Choque Térmico Pequenas/genética , Hordeum/fisiologia , Cotilédone/genética , Evolução Molecular , Aptidão Genética , Hordeum/genética , Israel , Microclima , Fases de Leitura Aberta , Filogenia , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Seleção Genética , Análise de SequênciaRESUMO
As the most ancient member of the wheat gluten family, the γ-gliadin genes are suitable for phylogenetic analysis among wheat and related species. Species in the grass genus Dasypyrum have been widely used for wheat cross breeding. However, the genomic relationships among Dasypyrum species have been little studied. We isolated 22 novel γ-gliadin gene sequences, among which 10 are putatively functional. The open reading frame lengths of these sequences range from 642 to 933 bp, and these putative proteins consist of five domains. Phylogenetic analyses showed that all Dasypyrum γ-gliadin gene sequences clustered in a large group; D. villosum and tetraploid D. breviaristatum γ-gliadin gene sequences clustered in a subgroup, while diploid D. breviaristatum γ-gliadin gene sequences clustered at the edge of the subgroup. All of the Dasypyrum γ-gliadin gene sequences were absent in three major T cell-stimulatory epitopes binding to HLA-DQ2/8 in celiac disease patients. Based on the phylogenetic analyses, we suggest that D. villosum and tetraploid D. breviaristatum evolved in parallel from a diploid ancestor D. breviaristatum.
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Gliadina/genética , Filogenia , Proteínas de Plantas/genética , Poaceae/genética , Sequência de Aminoácidos , Doença Celíaca/genética , Doença Celíaca/imunologia , Doença Celíaca/metabolismo , DNA de Plantas/química , DNA de Plantas/genética , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/metabolismo , Gliadina/classificação , Gliadina/imunologia , Antígenos HLA-DQ/imunologia , Antígenos HLA-DQ/metabolismo , Humanos , Dados de Sequência Molecular , Proteínas de Plantas/imunologia , Poaceae/classificação , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência de AminoácidosRESUMO
OBJECTIVE: This study aimed to evaluate the lung protection effect of an individualized protective ventilation strategy based on lung impedance tomography (EIT) technology in patients with partial pulmonary resection. PATIENTS AND METHODS: Eighty patients of any gender, American Society of Anesthesiologists (ASA) classification I-II, age 30-64 years and body mass index (BMI) 18-28 kg/m2 who underwent elective thoracoscopic partial lung resection were selected and divided into 2 groups (n=40) using the random number table method: [positive end-expiratory pressure (PEEP) by electrical impedance tomography (EIT)] PEEPEIT group (experimental group) and control group. The PEEPEIT group used volume-controlled ventilation after one-lung ventilation, setting a tidal volume of 6 ml/kg and titrating the optimal PEEP value by EIT. Group C used volume-controlled ventilation after one-lung ventilation, setting a tidal volume of 6 ml/kg and a PEEP of 5 cm H2O. Clinical data were collected and recorded at 5 min after double lung ventilation (T0), single lung ventilation, 30 min after PEEP setting (T1), 60 min after PEEP setting (T2), the end of surgery, 10 min after resumption of double lung ventilation (T3) and 10 min after removal of the tracheal tube (T4), and serum surface active substance-associated protein-A (SP-A) concentrations were measured at T0, T3 and 1 d after surgery (T5). RESULTS: PEEP values were higher in the PEEPEIT group than in the control group at T1 and T2 (p-value <0.05); oxygenation index (OI) was higher in the PEEPEIT group compared to the control group at T2 and T3 (p-value <0.05); pulmonary dynamic compliance (Cdyn) was higher in the PEEPEIT group compared to the control group at T1 and T2 (p-value <0.05); intrapulmonary shunt rate (Qs/Qt) was lower in the PEEPEIT group compared to the control group at T1, T2 and at T3, the intrapulmonary shunt rate (Qs/Qt) was reduced in the PEEPEIT group compared to group C (p-value <0.05); at T5, the SP-A protein was reduced in the PEEPEIT group compared to group C. There was no statistically significant difference in the incidence of postoperative pulmonary complications between the two groups (p-value >0.05). CONCLUSIONS: The EIT-guided individualized protective ventilation strategy has a lung-protective effect in patients undergoing thoracoscopic partial lung resection.
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Pulmão , Ventilação Monopulmonar , Humanos , Adulto , Pessoa de Meia-Idade , Pulmão/cirurgia , Respiração com Pressão Positiva/métodos , Volume de Ventilação Pulmonar , Tomografia Computadorizada por Raios XRESUMO
Nickel phosphide-embedded graphene, prepared by the hydrothermal reaction of red phosphorus, nickel chloride, and graphene oxide in a mixture of ethylene glycol-water, is investigated as the counter electrode of DSSCs. It is demonstrated that the DSSC with the nickel phosphide-embedded graphene as the new counter electrode presents an excellent performance competing with that of the Pt electrode.
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BACKGROUND AND PURPOSE: Ketanserin, a selective 5-HT receptor antagonist, prolongs the QT interval of ECG in patients. The purpose of the present study was to determine whether ketanserin would block human cardiac ether-à-go-go-related gene (hERG) potassium channels. EXPERIMENTAL APPROACH: Whole-cell patch voltage-clamp technique was used to record membrane currents in HEK 293 cells expressing wild type or mutant hERG channel genes. KEY RESULTS: Ketanserin blocked hERG current (I(hERG)) in a concentration-dependent manner (IC50=0.11 microM). The drug showed an open channel blocking property, the block increasing significantly at depolarizing voltages between +10 to +60 mV. Voltage-dependence for inactivation of hERG channels was negatively shifted by 0.3 microM ketanserin. A 2.8 fold attenuation of inhibition by elevation of external K+ concentration (from 5.0 to 20 mM) was observed, whereas the inactivation-deficient mutants S620T and S631A had the IC50s of 0.84 +/- 0.2 and 1.7 +/-0.4 microM (7.6 and 15.4 fold attenuation of block). In addition, the hERG mutants in pore helix and S6 also significantly reduced the channel block (2-59 fold) by ketanserin. CONCLUSIONS AND IMPLICATIONS: These results suggest that ketanserin binds to and blocks the open hERG channels in the pore helix and the S6 domain; channel inactivation is also involved in the blockade of hERG channels. Blockade of hERG channels most likely contributes to the prolongation of QT intervals in ECG observed clinically at therapeutic concentrations of ketanserin.
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Canais de Potássio Éter-A-Go-Go/efeitos dos fármacos , Ketanserina/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Antagonistas da Serotonina/farmacologia , Linhagem Celular , Relação Dose-Resposta a Droga , Eletrocardiografia , Canais de Potássio Éter-A-Go-Go/metabolismo , Humanos , Concentração Inibidora 50 , Ketanserina/administração & dosagem , Ketanserina/efeitos adversos , Técnicas de Patch-Clamp , Potássio/metabolismo , Bloqueadores dos Canais de Potássio/administração & dosagem , Bloqueadores dos Canais de Potássio/efeitos adversos , Receptor 5-HT2C de Serotonina/efeitos dos fármacos , Antagonistas da Serotonina/administração & dosagem , Antagonistas da Serotonina/efeitos adversosRESUMO
PURPOSE: Various ventricular assist devices (VADs) have been developed for clinical use in recent years. The aim of a multidisciplinary research team at the Fuwai Hospital of the Peking Union Medical College is to design and develop an axial flow left ventricular assist device (LVAD) for adults. METHODS: Using Computational Fluid Dynamics (CFD), the inflow characteristics of the axial flow pump were analyzed. After CFD analysis, the axial pump was fabricated using a 5-axis, computer numerical control (CNC) milling machine. Performances of the pump both in vitro and in vivo were tested. RESULTS: This VAD, which was developed after numerous CFD analyses for the flow characteristics of the pump, is 58.5 mm long, 30 mm wide and weighs 120 g. The pump can deliver 5 lpm for pressures of 100 mmHg over 8500 rpm. The NIH value was 0.01 g/100 L. The hemolysis, which was evaluated in an in vivo test, was a bit higher than the normal value, but remained within an acceptable range. CONCLUSIONS: Performance of the pump in vitro and in vivo was considered sufficient for an LVAD. Further design improvements are being undertaken in terms of hemolysis and thrombosis to improve the biocompatibility of the pump.
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Coração Auxiliar , Hemodinâmica , Adulto , Animais , China , Simulação por Computador , Coração Auxiliar/efeitos adversos , Hemólise , Humanos , Teste de Materiais , Modelos Cardiovasculares , Análise Numérica Assistida por Computador , Desenho de Prótese , Ovinos , Trombose/etiologiaRESUMO
OBJECTIVE: MicroRNA-1294 (miR-1294) was reported to act as a tumor suppressor in several cancers. However, the biological function of miR-1294 in osteosarcoma (OS) has not been investigated. We, therefore, investigated the clinical significance and underlying mechanisms of miR-1294 in OS. PATIENTS AND METHODS: Quantitative Real-Time-Polymerase Chain Reaction (qRT-PCR) was conducted to detect the levels of miR-1294. Targets of miR-1294 were validated by luciferase reporter assay and Western blot. In vitro functional assays were performed to investigate the effects of miR-217 on cell proliferation and invasion. RESULTS: We found miR-1294 was downregulated in OS tissues and cell lines. Downregulation of miR-1294 has a significant negative impact on the overall survival of OS patients. Overexpression of miR-1294 suppresses OS cell proliferation and invasion in vitro. Then, luciferase reporter assay validated Homeobox A9 (HOXA9) was a downstream target of miR-1294. Expression patterns of miR-1294 were inversely correlated with HOXA9 in OS tissues, strengthening the findings from the luciferase reporter assay. Further functional assays revealed that overexpression of HOXA9 could reverse the inhibition effects of miR-1294 on cell proliferation and invasion. CONCLUSIONS: These results suggested miR-1294 functions as a tumor suppressor in OS progression by targeting HOXA9.
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Neoplasias Ósseas/prevenção & controle , Genes Supressores de Tumor/fisiologia , Proteínas de Homeodomínio/genética , MicroRNAs/fisiologia , Osteossarcoma/prevenção & controle , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Proliferação de Células , Células Cultivadas , Humanos , Invasividade Neoplásica , Osteossarcoma/genética , Osteossarcoma/patologiaRESUMO
OBJECTIVE: Recently, our team has demonstrated that voltage-gated delayed rectifier K(+) current (IK(DR)) and Ca(2+)-activated K(+) current (I(KCa)) are present in rat bone marrow-derived mesenchymal stem cells; however, little is known of their physiological roles. The present study was designed to investigate whether functional expression of IK(DR) and I(KCa) would change with cell cycle progression, and whether they could regulate proliferation in undifferentiated rat mesenchymal stem cells (MSCs). MATERIALS AND METHODS: Membrane potentials and ionic currents were recorded using whole-cell patch clamp technique, cell cycling was analysed by flow cytometry, cell proliferation was assayed with DNA incorporation method and the related genes were down-regulated by RNA interference (RNAi) and examined using RT-PCR. RESULTS: It was found that membrane potential hyperpolarized, and cell size increased during the cell cycle. In addition, IK(DR) decreased, while I(KCa) increased during progress from G(1) to S phase. RT-PCR revealed that the mRNA levels of Kv1.2 and Kv2.1 (likely responsible for IK(DR)) reduced, whereas the mRNA level of KCa3.1 (responsible for intermediate-conductance I(KCa)) increased with the cell cycle progression. Down-regulation of Kv1.2, Kv2.1 or KCa3.1 with the specific RNAi, targeted to corresponding gene inhibited proliferation of rat MSCs. CONCLUSION: These results demonstrate that membrane potential, IK(DR) and I(KCa) channels change with cell cycle progression and corresponding alteration of gene expression. IK(DR) and intermediate-conductance I(KCa) play an important role in maintaining membrane potential and they participate in modulation of proliferation in rat MSCs.
Assuntos
Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Canais de Potássio/metabolismo , Animais , Sequência de Bases , Ciclo Celular , Proliferação de Células , Tamanho Celular , Células Cultivadas , Primers do DNA/genética , Potenciais da Membrana , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio/genética , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RatosRESUMO
Spinel Zn2SnO4 particles with the cubic shape are prepared via a hydrothermal reaction under mild conditions. The hydrothermal conditions, such as alkaline concentration, reaction temperature, and duration time, have an important influence on the product structure and the performance of the electrode prepared with the product. The optimized product is cube-shaped Zn2SnO4 crystalline, which is prepared with 0.4 M of NaOH solution at 200 degrees C for 24 h. These cube-shaped Zn2SnO4 particles with the spinel structure exhibit a large electrochemical capacity of 988 mA h/g and a relatively good capacity retention as anode materials for Li-ion battery. The structures of the as-prepared product and specimens taken from the electrodes after charging-discharging cycles are analyzed by X-ray diffraction, scanning electron microscopy, and transition electron microscopy techniques. In particular, it is found for the first time that the spinel Zn2SnO4 structure exists to a great extent after the first cycle and contributes to the extremely high reversible capacity during the following cycles.