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91.
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本文用离体血管条生物测定法观察血管对去甲肾上腺素(NE)及高钾去极化(HiK~ )的收缩反应及~(46)Ca~(2 )示踪测定血管平滑肌细胞钙跨膜内流。实验表明:肾性高血压大鼠主动脉及肠系膜动脉对NE和HiK~ 的收缩反应显著增高。反应性的这一变化与细胞钙内流有明显关系,其中通过血管平滑肌细胞膜电压依赖性钙通道内流的钙增多在血管反应性增高中有重要作用。  相似文献   
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BackgroundDyschromatosis universalis hereditaria (DUH) is a rare genodermatosis characterized by hyper‐ and hypo‐pigmented macules on the face, trunk, and extremities. The condition causes severe cosmetic problem which can lead to significant psychological distress to the patients and bear a negative impact on society. DUH is a condition with genetic heterogeneity. The SASH1 gene was recently identified as pathogenic genes in DUH patients.MethodsTwo families clinically diagnosed with dyschromatosis universalis hereditaria were enrolled. Whole‐exome sequencing combined with Sanger sequencing and bioinformatics analysis was performed in the probands. MutationTaster, CADD, SIFT, PolyPhen‐2, and LRT software, and The American College of Medical Genetics and Genomics Standards and Guidelines were employed to assess the pathogenicity of detected missense mutations. One hundred healthy unrelated Chinese individuals were used as controls. All participants signed an informed consent form.ResultsGenetic screening revealed a heterozygous SASH1 c.1547G>A (p.Ser516Asn) mutation for patients in family 1, and SASH1 c.1547G>T (p.Ser516Ile) for family 2. Both such de novo mutations are located in a highly conserved SLY domain in SASH1, have not been previously reported in any publication, and were not detected in any control databases.ConclusionsThe novel heterozygous mutations, SASH1 c.1547G>A and c.1547G>T, are likely responsible for the DUH phenotype in these two families. Our study expands the mutation spectrum of DUH. Whole‐exome sequencing showed its efficiency in the diagnostic of hereditary skin disorders.  相似文献   
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PurposeThe aim of this study is to prospectively investigate the influence of ADRB and COMT gene polymorphisms on postoperative outcomes of patients undergoing cardiac surgery.MethodsThis prospective cohort study included 223 patients undergoing elective cardiac valve surgery using cardiopulmonary bypass. Demographic information, intraoperative data, postoperative data, and blood samples were collected. Patients were genotyped for single-nucleotide polymorphisms (SNPs) of ADRB1 rs1801253, ADRB2 rs1042713, and COMT rs4680. Major adverse cardiovascular and cerebrovascular events (MACCEs) were used as the primary outcome to evaluate the postoperative prognosis of patients. Secondary outcomes included the duration of mechanical ventilatory support, intensive care unit stay, postoperative hospital stay, and postoperative need of inotropic or vasoactive agents.FindingsThe overall incidence of MACCEs was 15.2%. Among 3 SNP loci, only different genotyped carriers of ADRB2 rs1042713 had statistically significant differences in the incidence of MACCEs (P = 0.005), especially for acute kidney injury (P = 0.023). The proportions of postoperative norepinephrine demand of patients carrying the AA genotype of ADRB2 rs1042713 (P = 0.016) and the AG genotype of COMT rs4680 (P = 0.018) were low. The duration of mechanical ventilatory support (P = 0.034) and postoperative hospital stay (P = 0.045) of patients carrying the AG genotype of COMT rs4680 was shortest. After multiple logistic regression analysis, we found that the G allele carriers of ADRB2 rs1042713 had a higher risk of MACCEs (AG vs AA genotype: odds ratio [OR] = 4.348; 95% CI, 1.529–12.359, P = 0.006; GG vs AA genotype: OR = 3.722; 95% CI, 1.060–13.071; P = 0.040), in particular with acute kidney injury (AG vs AA genotype: OR = 5.273; 95% CI, 1.093–25.451; P = 0.038; GG vs AA genotype: OR = 7.533; 95% CI, 1.275–44.522; P = 0.026). There was no SNP-SNP interaction found among the 3 SNPs with multifactor dimensionality reduction analysis.ImplicationThe ADRB2 rs1042713 polymorphism might be related to prognosis of patients undergoing cardiac surgery. Patients carrying the G allele of ADRB2 rs1042713 had a higher risk of developing MACCEs, especially acute kidney injury. chictr.org.com identifier: ChiCTR1800015105.  相似文献   
96.
《Immunobiology》2013,218(2):255-262
Eosinophils are the principal effector cells of allergic inflammation, and hematopoietic cytokine granulocyte macrophage colony-stimulating factor (GM-CSF) is the primary cytokine that activates and prolongs the survival of eosinophils in local inflammatory sites by mediating anti-apoptotic activity in allergic inflammation. To investigate the immunopathological role of microRNA (miRNA) in allergic inflammation, we elucidated the regulatory mechanisms of miRNA on the GM-CSF-mediated in vitro survival in eosinophils. Eosinophils were purified from fresh human peripheral blood buffy coat fraction obtained from adult volunteer using microbead magnetic cell sorting. The apoptosis, viability and phosphorylation of extracellular signal-regulated kinase (ERK) were assessed by flow cytometry, and the expression of miRNA was analyzed using Agilent Human miRNA Microarray with Human miRNA Microarray Version 3 and real time RT-PCR. We have confirmed the increased in vitro viability of GM-CSF-treated eosinophils and upregulated expression of miRNA-21* (miR-21*), a complementary miRNA of miR-21, in GM-CSF-treated eosinophils. The transfection of pre-miR miR-21* precursor molecule could up-regulate the miR-21* expression, subsequently enhance the GM-CSF-activated ERK pathway and reverse the apoptosis of eosinophils, while anti-miR-21* inhibitor could down-regulate the miR-21* expression, suppress the GM-CSF-activated ERK pathway and enhance the apoptosis. Our results should shed light on the potential immunopathological role of miRNA-21* regulating the in vitro apoptosis of eosinophils and development of novel molecular treatment of allergic inflammation.  相似文献   
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The aim was to assess 3-year longitudinal data using 6MWT in 26 ambulant boys affected by DMD carrying nonsense mutations and to compare their results to other small mutations. We also wished to establish, within the nonsense mutations group, patterns of change according to several variables. Patients with nonsense mutations were categorized according to the stop codon type newly created by the mutation and also including the adjacent 5′ (upstream) and 3′ (downstream) nucleotides. No significant difference was found between nonsense mutations and other small mutations (p > 0.05) on the 6MWT. Within the nonsense mutations group, there was no difference in 6MWT when the patients were subdivided according to: Type of stop codon, frame status of exons involved, protein domain affected. In contrast, there was a difference when the stop codon together with the 3′ adjacent nucleotide (“stop+4 model”) was considered (p < 0.05) with patients with stop codon TGA and 3′ adjacent nucleotide G (TGAG) having a more rapid decline. Our finding suggest that the stop+4 model may help in predicting functional changes. This data will be useful at the time of interpreting the long term follow up of patients treated with Ataluren that are becoming increasingly available.  相似文献   
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The present study aimed to assess the prevalence and incidence rate of pulmonary arterial hypertension (PAH) in Systemic Sclerosis (SSc). The review was undertaken using MEDLINE and SCOPUS from June 1962 to May 2019 and the terms: (“Scleroderma, Systemic”[MesH]) AND “Hypertension, Pulmonary”[MesH]. The Newcastle-Ottawa Scale (NOS) was used for the qualifying assessment. The inverse variance-weighted method was performed. Twenty-four studies were included in the global PAH prevalence study. They comprised data from 9804 SSc patients. The overall PAH prevalence found was 6.4% (95%CI 5%–8.3%). Fourteen studies were included in the PAH prevalence study for lcSSc. They comprised data from 4987 lcSSc patients. The PAH prevalence found in lcSSc was 7.7% (95%CI 5.3%–11.1%). Twelve studies were included in the PAH prevalence study for dcSSc. They comprised data from 1790 dcSSc patients. The PAH prevalence found in dcSSc was 6.3% (95%CI 4.5%–8.9%). Fifteen studies showed PAH incidence of an entire SSc cohort. They comprised data from 5926 SSc patients. The overall PAH incidence found was 18.2 cases per 1000 person-years (95%CI 12–27.4). Eight studies showed PAH incidence for lcSSc. They comprised data from 2721 patients. The overall PAH incidence found in lcSSc was 20.4 cases per 1000 person-years (95%CI 10.1–41.1). Seven studies showed PAH incidence for dcSSc. They comprised data from 942 dcSSc patients. The overall PAH incidence found in dcSSc was 16.6 cases per 1000 person-years (95%CI 8.5–32.1).ConclusionThe overall PAH prevalence found was 6.4% (95%CI 5%–8.3%) and the overall PAH incidence 18.2 cases per 1000 person-years (95%CI 12–27.4).  相似文献   
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