肌切蛋白的结构与功能多样性

肌切蛋白（scinderin）是一种重要的肌动蛋白结合蛋白,在哺乳动物和脊椎动物中广泛表达.肌切蛋白作为凝溶胶蛋白超家族的成员之一,通过肌动蛋白丝切割、肌动蛋白聚集等方式来控制肌动蛋白的结构.肌切蛋白生物活性具有多样性,除影响肌动蛋白丝重组外,肌切蛋白还参与细胞胞吐作用、调节细胞运动、细胞分化等细胞活动.此外,肌切蛋白在慢性炎症、凝血过程、免疫性疾病和肿瘤发生发展中也发挥了重要作用.本文对肌切蛋白的结构特点、参与调节细胞的功能和机制进行概述.     

能谱CT优化胃肿瘤扫描辐射剂量对肾上腺嗜铬细胞瘤的诊断价值

目的:探讨能谱CT优化胃肿瘤扫描辐射剂量对肾上腺嗜铬细胞瘤的诊断价值。方法:采用回顾性、抽样、随机研究方法选择2012年9月到2017年2月在我院诊治的肾上腺嗜铬细胞瘤患者59例作为研究对象,所有患者都给予常规CT扫描与能谱CT优化胃肿瘤扫描,记录和比较辐射剂量与图像质量。结果:所有病例包膜均完整,边缘清楚,肿瘤内见单发或多发低密度区,肿瘤实质区呈不均匀显著强化。常规CT与能谱CT的图像质量主观评分分别为3.89±0.45分和4.54±0.34分;常规CT与能谱CT图像的胃肿瘤CT值分别为31.94±6.39HU和35.29±5.19HU,对比都有显著差异(P0.05)。能谱CT图像的膀胱和皮下脂肪图像噪声值都显著低于常规CT图像,对比差异都有统计学意义(P0.05);能谱CT扫描的CTDIvol和DLP分别为12.39±3.48mGy和624.10±39.19mGy.cm,都显著低于常规CT扫描的14.09±4.13mGy和653.92±56.29mGy.cm(P0.05)。结论:能谱CT优化胃肿瘤扫描在肾上腺嗜铬细胞瘤诊断中的应用能有效减少辐射剂量与图像噪声,提高图像CT值与主观质量,临床应用价值更高。     

重组人脑利钠肽联合多巴胺对心肾综合征伴低血压的疗效及对血清NT-proBNP水平的影响

目的:研究重组人脑利钠肽联合多巴胺对心肾综合征伴低血压的疗效及对血清NT-proBNP水平的影响。方法:收集2015年4月至2016年4月我院的90例心肾综合征伴低血压患者,按抽签法分为实验组和对照组,每组45例。对照组用多巴胺治疗,实验组在对照组基础上加用重组人脑利钠肽。观察两组治疗疗效,治疗前后血压、心率、心动图指标每搏输出量(SV)、左心室射血分数(LVEF)、左心室舒张末内径(LVEDD),N末端前体脑钠肽(NT-proBNP)、血肌酐(SCr)、胱抑素C(Cys C)水平的变化。结果:治疗后,实验组总有效率为93.33%,显著高于对照组(68.88%,P0.05);SBP、DBP、MAP、SV、LVEF均显著高于对照组(P0.05),HR、血清NT-proBNP、SCr水平显著低于对照组(P0.05);两组LVEDD比较差异无统计学意义(P0.05)。结论:重组人脑利钠肽联合多巴胺对心肾综合征伴低血压的疗效显著,可缓解心脏负荷,改善心肾功能,降低NT-proBNP水平,提高治疗安全性。     

High‐throughput analysis of vocalizations reveals sex‐specific changes in Fmr1 mutant pups

There have been several reports that individuals with Fragile X syndrome (FXS) and animal models of FXS have communication deficits. The present study utilized two different call classification taxonomies to examine the sex‐specificity of ultrasonic vocalization (USV) production on postnatal day (PD8) in the FVB strain of Fmr1 knockout (KO) mice. One classification protocol requires the investigator to score each call by hand, while the other protocol uses an automated algorithm. Results using the hand‐scoring protocol indicated that male Fmr1 KO mice exhibited longer calls (P = .03) than wild types on PD8. Male KOs also produced fewer complex, composite, downward, short and two‐syllable call‐types, as well as more frequency steps and chevron call‐types. Female heterozygotes exhibited no significant changes in acoustic or temporal aspects of calls, yet showed significant changes in call‐type production proportions across two different classification taxonomies (P < .001). They exhibited increased production of harmonic and frequency steps calls, as well as fewer chevron, downward and short calls. According to the second high‐throughput analysis, female heterozygotes produced significantly fewer single‐type and more multiple‐type syllables, unlike male KOs that showed no changes in these aspects of syllable production. Finally, we correlated both scoring methods and found a high level of correlation between the two methods. These results contribute further knowledge of sex differences in USV calling behavior for Fmr1 heterozygote and KO mice and provide a foundation for the use of high‐throughput analysis of neonatal USVs.     

Wnk kinases are positive regulators of canonical Wnt/β-catenin signalling

Wnt/β-catenin signalling is central to development and its regulation is essential in preventing cancer. Using phosphorylation of Dishevelled as readout of pathway activation, we identified Drosophila Wnk kinase as a new regulator of canonical Wnt/β-catenin signalling. WNK kinases are known for regulating ion co-transporters associated with hypertension disorders. We demonstrate that wnk loss-of-function phenotypes resemble canonical Wnt pathway mutants, while Wnk overexpression causes gain-of-function canonical Wnt-signalling phenotypes. Importantly, knockdown of human WNK1 and WNK2 also results in decreased Wnt signalling in mammalian cell culture, suggesting that Wnk kinases have a conserved function in ensuring peak levels of canonical Wnt signalling.     

Prevalence,comorbidities and mortality of toxic shock syndrome in children and adults in the USA

Toxic Shock Syndrome (TSS), a superantigen‐mediated illness, is characterized by rash, hypotension and multi‐organ dysfunction. Predictors of TSS and related morbidity and mortality are poorly defined. In this study, data on 61,959,084 hospitalizations from the 2003–2012 Nationwide Inpatient Sample, a 20% stratified sample of US hospitalizations, were analyzed and ICD‐9‐CM coding used to identify 4491 hospitalizations with a diagnosis of TSS. Incidence, in‐hospital mortality rate, comorbidities, length of stay and costs of care attributable to TSS were determined. In multivariate survey logistic regression models, TSS was associated with female sex (adjusted odds ratio [95% confidence interval], 1.54 [1.48–1.60]), younger age (0–17 years, 2.17 [2.06–2.29]; 40–59: 0.53 [0.50–0.56]; 60–79: 0.28 [0.26–0.30]; 80+: 0.13 [0.11–0.14] compared with 18–39) and race/ethnicity (black, 0.63 [0.59–0.67]; Hispanic: 0.60 [0.56–0.64]; Asian, 1.11 [1.00–1.11]; and other, 0.83 [0.75–0.92] compared with white). Patients with TSS had a three‐fold greater cost of care (mean: $36,656 ± 942) and length of stay (LOS) (mean: 10.65 ± 0.23 days) than patients without TSS. Shared predictors of increased LOS and costs in patients with TSS were male sex; age 40–79 years; Black, Hispanic, Asian and other race/ethnicity; and more than one chronic condition. Predictors of in‐hospital mortality included respiratory failure (13.66 [11.37–16.43]), liver disease/failure (3.36 [2.59–4.34]), chickenpox (91.26 [27.74–300.25]), coagulopathy (2.14 [1.85–2.48]), and higher age. In conclusion, there are significant racial/ethnic, socioeconomic, and comorbid disparities in the incidence and mortality of TSS in adults and children in the USA.

     

Evidence of alterations in the expression of orphan receptors GPR26 and GPR39 due to the etiology of the metabolic syndrome

Aims: Metabolic syndrome (MS) is composed of several metabolic abnormalities that increase the risk of cardiovascular diseases and diabetes. Although there are treatments for the components of MS, this pathology maintains a high mortality, suggesting that there are other mechanisms in which orphan receptors such as GPR26 and GPR39 may be involved. For this reason, the aim of this work was to evaluate the expression of GPR26 and GPR39 orphan receptors in two models of MS (diet and genetics).

Materials and methods: We used male Wistar rats, which received 70% fructose in drinking water for 9 weeks, and obese Zucker rats. We measured weight, blood pressure, glucose, triglycerides, total cholesterol, HDL cholesterol, LDL cholesterol to determine the MS and the expression of the orphan receptors GPR26 and GPR39 in brain, heart, aorta, liver, and kidney by RT-PCR.

Results: The analysis of the expression of the orphan receptors GPR26 and GPR39 showed that the receptors are expressed in some tissues, but the expression of the GPR26 tends to decrease in the heart and aorta, whereas in the brain, no changes were observed, this receptor is not expressed in the liver and kidney of both strains. The expression of GPR39 isoforms depends on the tissue and MS model.

Conclusions: We conclude that the orphan receptors GPR26, GPR39v1, and GPR39v2 are expressed in different tissues and their profile expression is dependent on the etiology of the MS.     

胎盘型谷胱甘肽S－转移酶基因在胃癌中的表达

用Ｄｉｇ－ＧＳＴ－πｃＤＮＡ探针分子杂交方法,检测了正常胃组织,胃癌及相应癌旁正常组织中ＧＳＴ－πＤＮＡ和ＧＳＴ－πＲＮＡ水平,发现ＧＳＴ－πＤＮＡ水平没有明显变化,而ＧＳＴ－πＲＮＡ在８例胃癌组织中有６例高于正常胃组织,在１２例低分化腺癌中有７例癌旁正常组织高于相应癌组织,表明ＧＳＴ－π基因表达增加与胃癌有关,而且早于细胞形态的变化。     

Wing dimorphism and the migratory syndrome: Correlated traits for migratory tendency in wing dimorphic insects

The hypothesis that the morphological, physiological, and behavioral traits comprising the migratory syndrome in insects are genetically correlated through pleiotropic effects of genes controlling the titre of a common hormonal determinant is explored. Evidence that juvenile hormone (JH) influences the component traits of the migratory syndrome is presented, and thus JH is assumed to be the underlying, common determinant. However, readers are cautioned that this does not imply that JH is solely responsible for these traits, nor is this necessary for the arguments presented. For wing dimorphic taxa, the “correlated traits hypothesis” predicts covariance within wing morphs between JH titre and the proportion winged. Four simple genetic models for wing-morph determination are considered: single-locus with short-winged (SW) dominant; single-locus with long-winged (LW) dominant; polygenic, fixed threshold, shifting distribution; and polygenic, shifting threshold, fixed distribution. In each case, wing morphology is assumed to be a threshold trait with the liability being JH titre at some critical stage of development. All models predict covariation between %LW and the mean JH titre of at least one of the wing morphs, but the form and direction of the relationship depends critically on the genetic model used. The results suggest that we should expect the traits associated with the migratory syndrome, and hence the trade-offs associated with the evolution of wing dimorphism, to be correlated with proportion winged and, in this sense, to be frequency-dependent.