创新思维对肾移植模型制作教学的促进作用

大鼠肾移植模型是研究肾移植排斥反应发生机制、治疗措施以及诱导免疫耐受的重要平台,但其制作复杂,在传统教学中存在诸多问题。对此,我们在教学中充分发挥创新思维,改进了教学方式,建立了多项新技术,显著提高了以显微外科技术为基础的大鼠肾移植模型制作的教学效率与质量,现将体会报告如下。1应用现代教学手段解决传统教学中的难题1.1大鼠肾移植模型的制作特点以及传统教学存在的问题该模型制作主要依赖显微外科技术,教学中,从解剖结构、手术器械到手术操作的突出特点是“精细、微小”,也是教学的难点。传统教学主要依靠文字教材以及部分挂…     

鼻咽癌患者血清TGF-β1、IL-8水平和T淋巴细胞亚群水平测定的临床意义

目的：探讨了鼻咽癌患者血清TGF-β1、IL-8和T淋巴细胞亚群水平的变化及意义。方法：分别应用放免法、酶联免疫法和单克隆抗体测定对31例鼻咽癌患者进行了血清TGF-β1、IL-8水平和T淋巴细胞亚群的测定,并与35例正常健康人作比较。结果：鼻咽癌患者血清TGF-β1、IL-8和CD8水平非常显著高于正常人组（P〈0．01）,而CD3、CD4、CD4／CD8比值又非常显著低于正常人组（P〈0．01）。鼻咽癌患者血清TGF-β1水平和CD4细胞数量及与CD4／CD8比值呈负相关,与CD8细胞呈正相关。结论：观察鼻咽癌患者血清TGF-β1、IL-8水平和T淋巴细胞亚群水平的改变有助于鼻咽癌的诊断及对预后的评价。     

An outbreak of avian influenza subtype H9N8 among chickens in South Korea.

Low pathogenic avian influenza subtype H9N8 was diagnosed on a Korean native chicken farm in Gyeonggi province, South Korea, in late April 2004. Clinical signs included moderate respiratory distress, depression, mild diarrhoea, loss of appetite and a slightly elevated mortality (1.4% in 5 days). Pathologically, mucopurulent tracheitis and air sacculitis were prominently found with urate renal deposition. The isolated A/chicken/Kr/164/04 (H9N8) had an Ala-Ser-Gly-Arg (A/S/G/R) motif at the cleavage site of haemagglutinin, which has been commonly found in H9N2 isolated from Korean poultry. Phylogenetic analysis of the haemagglutinin and neuraminidase genes of the H9N8 avian influenza virus (AIV) isolate showed that reassortment had occurred. Its haemagglutinin gene was similar to that of Korean H9N2 AIVs, but its neuraminidase gene was closely related to that of A/WBF/Kr/KCA16/03 (H3N8) isolated from the faeces of wild birds in Korea. The pathogenicity of the isolate was tested on 6-week-old specific pathogen free chickens. The inoculated virus (H9N8) was recovered from most tested organs, including the trachea, lung, kidney, spleen, and caecal tonsil. This is the first report of an outbreak of low pathogenic avian influenza in chickens caused by AIV subtype H9N8.     

Ca2+-desensitizing hypoxic vasorelaxation: pivotal role for the myosin binding subunit of myosin phosphatase (MYPT1) in porcine coronary artery

Acute hypoxia dilates most systemic arteries leading to increased tissue perfusion. We showed that at high stimulus conditions, porcine coronary artery was relaxed by hypoxia without a change in [Ca²⁺]_i. This 'Ca²⁺-desensitizing hypoxic relaxation' was validated in permeabilized porcine coronary artery smooth muscle (PCASM) in which hypoxia decreased force and myosin regulatory light chain phosphorylation (p-MRLC) despite fixed [Ca²⁺]. Rho kinase-dependent phosphorylation of MYPT1 (p-MYPT1) is associated with decreased MRLC phosphatase (MLCP) activity, and increased Ca²⁺ sensitivity of both p-MRLC and force. We tested the hypothesis that hypoxia induces Ca²⁺-desensitizing hypoxic relaxation via dephosphorylation of p-MYPT1, consequently increasing MLCP activity and thus decreasing p-MRLC. α-Toxin-permeabilized PCASM pretreated with ATPγS did not relax in response to hypoxia. Moreover, when MRLC but not MYPT1 was protected from ATPγS thiophosphorylation by the MRLC kinase inhibitor ML7 (300 μ m ), hypoxia remained ineffective. In contrast, hypoxic relaxation was preserved with further addition of the Rho kinase inhibitor Y27632 (1 μ m ), to attenuate thiophosphorylation of MYPT1. Importantly, measurements of p-MRLC, and p-MYPT1 at T696 and T853 (human sequence) paralleled that of force. We conclude that Ca²⁺-desensitizing hypoxic relaxation requires dephosphorylation of p-MYPT1. Moreover, no kinases, other then those inhibited by ML7 and Y27632, nor their associated phosphoproteins can be involved in Ca²⁺-desensitizing hypoxic relaxation.     

HLA alleles and haplotypes in French North African immigrants

Human leukocyte antigen (HLA) haplotypes (n = 187) were genotyped and assigned by the mode of inheritance in migrant families from North Africa who reside in the Paris, France, area. The distribution of alleles and haplotypes in that population was compared with the one obtained in a control population of ancient French natives residing in the same area (248 independent haplotypes also assigned by the mode of inheritance were studied). The results in migrants reveal the following: (1) a higher diversity in the distribution of HLA-A and -DRB1 alleles; (2) lower frequencies of alleles common in our region, such as A*0201 B*1501, B*4001, and DRB1*0401 and increased frequencies of minor subtypes, such as A*3002 and DRB1*0402; and (3) distinct distributions of B/Cw, DRB1/DQB1 or B/Cw/DRB1/DQB1 haplotypes. The results also revealed that the four most frequent five-allele haplotypes in controls i.e., HLA-A*0101/B*0801/Cw*0701/DRB1*0301/DQB1*0201; A*0301/B*0702/Cw*0702/DRB1*1501/DQB1*0602 (both of Indo-Celtic origin); A*2902/B*4403/Cw*1601/DRB1*0701/DQB1*0202 (frequent in Western-Europeans); and A*0201/B*1501/Cw*0304/DRB1*0401/DQB1*0302, represent 10.5% of the total haplotypes in controls but 1.6% in North Africans. Conversely, 9 five-allele haplotypes in multiple copy in North Africans (among which A*3002/B*1801/Cw*0501/DRB1*0301/DQB1*0201 of Paleo-North African origin and A*0201/B*0702/Cw*0702/DRB1*1501/DQB1*0602 of ancient European and Paleo-North African origin) represent 9.6% of the total haplotypes in North Africans but 2.4% in controls. These results thus suggest a low degree of admixture between the two populations.     

Establishment of the major compatibility complex-dependent development of CD4+ and CD8+ T cells by the Cbl family proteins

Casitas B cell lymphoma (Cbl) proteins are negative regulators for T cell antigen receptor (TCR) signaling. Their role in thymocyte development remains unclear. Here we show that simultaneous inactivation of c-Cbl and Cbl-b in thymocytes enhanced thymic negative selection and altered the ratio of CD4(+) and CD8(+) T cells. Strikingly, the mutant thymocytes developed into CD4(+)- and CD8(+)-lineage T cells independent of the major histocompatibility complex (MHC), indicating that the CD4(+)- and CD8(+)-lineage development programs are constitutively active in the absence of c-Cbl and Cbl-b. The mutant double-positive (DP) thymocytes exhibited spontaneous hyperactivation of nuclear factor-kappa B (NF-kappaB). Additionally, they failed to downregulate the pre-TCR and pre-TCR signaling. Thus, our data indicate that Cbl proteins play a critical role in establishing the MHC-dependent CD4(+) and CD8(+) T cell development programs. They likely do so by suppressing MHC-independent NF-kappaB activation, possibly through downmodulating pre-TCR signaling in DP thymocytes.     

Pin1 gene mutation is a rare event in gastric cancer

The peptidyl-prolyl isomerase Pin1 is strikingly overexpressed in human cancers and is a novel regulator of beta-catenin. To determine whether somatic mutation of the Pin1 gene is involved in the development and/or progression of gastric cancer, we searched for mutations of the Pin1 gene in 95 gastric cancer specimens. The effect of Pin1 on beta-catenin expression was further examined in wild- and mutant-type Pin1-transfected HEK 293T cells. We found only one missense mutation that led to the substitution of alanine by aspartic acid at codon 118 of the Pin1 gene. On transfection study, the mutant Pin1 showed an increased expression of beta-catenin. However, the mutation had no effect on expression of the Pin1 protein in the case with Pin1 mutation. These results suggest that Pin1 may not play a role in the development or progression of gastric cancer.     

Heme oxygenase protects hippocampal neurons from ethanol-induced neurotoxicity

Ethanol has deleterious effects on neuronal cells both in vivo and in vitro, but the mechanisms are unknown. Here, treatment with increasing doses of ethanol (from 20 up to 600mM) decreased the viability of a mouse hippocampal neuroblastoma cell line, HT22. The glutathione concentration decreased and intracellular reactive oxygen species (ROS) increased in a dose-and time-dependent manner, suggesting that the neurotoxicity was due to oxidative stress. Expression of heme oxygenase (HO)-1, a redox regulator and heat shock protein, increased with time after ethanol treatment, but HO-2 was expressed constitutively. The addition of 5microM zinc protoporphyrin IX (ZnPP IX), a competitive HO inhibitor, with the ethanol further reduced cell viability and increased intracellular ROS, but these effects were reversed by co-treatment with 50nM bilirubin, a well-known antioxidant and a product of HO catalysis. These results suggest that HO has a protective role in hippocampal neurons as an intrinsic factor against ethanol-induced oxidative stress and the protection depends on the degree of oxidative stress.     

Prenatal features of 17q12 microdeletion and microduplication syndromes: A retrospective case series

ObjectiveTo present the experience on prenatal features of 17q12 microdeletion and microduplication syndromes.Materials and methodsPrenatal chromosomal microarray analysis (CMA) were conducted between January 2015 and December 2018 at a single Chinese tertiary medical centre. Information of cases identified with 17q12 microdeletion or microduplication syndromes were retrospectively collected. Foetal ultrasonographic findings were reviewed, and other information about the gestation week at diagnosis, inheritance and pregnancy outcomes were also included.ResultsTen pregnancies with 17q12 microdeletion and 4 with 17q12 microduplication were identified. The copy number variation (CNV) sizes were 1.39–1.94 Mb in the deleted cases and 1.42–1.48 Mb in the duplicated cases, respectively. All the duplicated and deleted regions included HNF1B and LHX1 genes. Most individuals with 17q12 deletion presented kidney anomalies (9/10), with renal hyperechogenicity being the most common finding (7/10). Fetuses with 17q12 duplication presented a wide phenotypic spectrum, including “double bubble” sign, structural anomalies of the heart and growth anomalies.ConclusionsOur experience further demonstrated the high correlation between 17q12 microdeletion and renal anomalies especially hyperechogenic kidneys. Structural anomalies of the heart were newly identified phenotypes of 17q12 duplication during prenatal period. Besides, growth anomalies and duodenal atresia might be associated with the duplication.     

Prenatal diagnosis of congenital nephrotic syndrome of the Finnish type in a Chinese family

ObjectiveTo explore the genetic bias in a Chinese family suspected of having congenital nephrotic syndrome of the Finnish type (CNF).Case reportWe developed a prenatal genetic diagnosis in a Chinese family with CNF. A single heterozygous mutation (c.3213delG) was found in the foetus IId and we presumed that it was an asymptomatic carrier of the normal phenotype. Additionally, two compound heterozygous variants (c.3213delG and c.3478C > T) were discovered in the foetus IIe, which were inherited from the mother and father, respectively. We performed further pathological examinations after medical abortion. Kidney histopathology and immunofluorescence results were similar to those reported in previous studies.ConclusionPrenatal genetic diagnosis of CNF still requires further research to explore the pathogenicity of suspected mutations.