Regulation of PTC phenotype and function by TGF-β1: implications for transdifferentiation

Introduction There is now increasing evidence that proximal tubular cells (PTCs) contribute to renal interstitial fibrosis by alteration of matrix turnover and by the generation of pro‐fibrotic cytokines such as TGF‐β1. Recent studies suggest that, through a process of transdifferentiation, the PTCs are one source of the interstitial myofibroblasts that directly drive the fibrotic process. The aim of this work was to examine the role and mechanism by which TGF‐β1 may regulate PTC phenotype and function. Methods Experiments were performed using both primary‐cultures of PTC and the human PTC cell line HK2. All experiments were performed on growth‐arrested cells in the absence of serum. Results TGF‐β1 altered cell phenotype, assessed by light microscopy, with cells appearing elongated and spindle‐shaped. This was associated with loss of cell–cell contact and rearrangement of the actin cytoskeleton, increased formation of stress fibres and focal adhesions. Disruption of the actin cytoskeleton with cytochalasin‐D prevented phenotypic alterations following addition of TGF‐β1. Transient transfection with Smad‐2/‐4 or Smad‐3/‐4 expression vectors did not alter cell phenotype. Previously, we have demonstrated β‐catenin translocation to PTC nuclei and its association with Smad proteins following addition of TGF‐β1, suggesting the possibility that TGF‐β1 may modulate Wnt signalling. Wnt‐responsive Xtwn‐reporter construct was, however, silent in response to TGF‐β1. Similarly, a second Wnt‐/LEF‐1‐regulated element Toplflash, which does not contain Smad‐binding sites, was insensitive to TGF‐β1 signalling. In contrast, phenotypic changes in response to TGF‐β1 were abrogated by inhibitors of the RhoA downstream target ROCK, which also prevented loss of cell–cell contact and adherens junction disassembly. Removal of TGF‐β1 and addition of 1% FCS, however, reverted cell phenotype to a typical cobblestone epitheliod appearance, suggesting that TGF‐β1 did not result in terminal PTC transdifferentiation. Cells grown on tissue culture dishes coated with either type‐I or type‐III collagen also acquired an elongated fibroblastic phenotype; this effect was exaggerated by the addition of TGF‐β1. In contrast to the cells stimulated with TGF‐β1 alone, following stimulation by both TGF‐β1 and exposure to interstitial collagens, cell phenotype was stable in that it was not reversed upon removal of TGF‐β1 and addition of FCS. Addition of TGF‐β1 to cells grown on type‐IV collagen had no greater effect than TGF‐β1 alone. Addition of TGF‐β1 alone had little effect on the expression of α‐SMA. In contrast, cells grown on either type‐I or type‐III collagen, following addition of TGF‐β1, demonstrated marked increased expression of α‐SMA, which appeared to be incorporated into the cell cytoskeleton. Similarly, the combination of interstitial collagen (either type‐I or type‐III) and TGF‐β1 had synergistic effect on the relocation and down‐regulation of the epithelial markers E‐cadherin and cytokeratin. Finally, the results demonstrated synergistic effects of coating with interstitial collagen (either type‐I or type‐III), on cell ‘fibroblastic’ cell function as assessed by cell migration and by the synthesis of type‐III and type‐IV collagen. Conclusion The results of these in vitro experiments suggest that terminal transdifferentiation of proximal tubular epithelial cells is the result of a combination of the effects of the pro‐fibrotic cytokine TGF‐β1 and exposure of the cells to components of the interstitial extra‐cellular matrix to which the cells are not exposed in the absence of damage to the tubular basement membrane.     

MUC1粘蛋白在进展期胃癌中的表达及临床意义

目的检测MUC1粘蛋白在进展期胃癌中的表达,探讨其对胃癌预后的意义.方法采用免疫组化SP法,应用抗MUC1粘蛋白核心蛋白抗体(DF3抗体)检测60例胃癌根治标本及对照组20例胃正常黏膜组织标本MUC1粘蛋白表达.采用χ2检验及Kaplan-Meier生存曲线进行统计分析.结果 MUC1粘蛋白阳性表达率55%(33/60).有淋巴结转移胃癌组MUC1粘蛋白阳性表达率为71.0%(22/31),无淋巴结转移组MUC1粘蛋白阳性表达率为37.9%(11/29),组间差别显著(P<0.05).按PTNM分期,Ⅰ期胃癌的MUC1粘蛋白阳性表达率为20%,Ⅱ期表达率68.8%,Ⅲ期表达率53.3%,Ⅳ期表达率78.6%,Ⅰ期与Ⅱ、Ⅲ、Ⅳ期间存在显著统计学差异(P<0.05).经Kaplan-Meier法生存曲线统计表明,MUC1阳性表达组5年生存状况较MUC1阴性组差(Log-Rank检验,P=0.037).结论在进展期胃癌中MUC1粘蛋白表达与淋巴结转移相关,随着胃癌的进展MUC1表达呈上升趋势;MUC1粘蛋白表达提示预后不良.     

呼吸机相关肺炎的发生原因及护理对策探讨

目的　为进一步探讨发生呼吸机相关肺炎的因素和护理措施。方法　对 70例使用机械通气辅助治疗的重症监护病房 (ICU)病人 ,取深部痰液进行细菌培养与分离及药敏试验 ,并采用综合护理措施。结果　 70例患者除 4例因原发病病情恶化死亡外 ,无一例因呼吸机相关肺炎而导致病情恶化 ,延误治疗 ,且缩短了住院时间。结论　正确的气道管理 ,合理应用抗生素 ,良好的饮食护理等辅助治疗 ,能够降低呼吸机相关因素肺炎的发病率     

颞部-颌下联合进路切除咽旁颞下区巨大肿瘤(附2例报道)

[目的]探讨切除侵犯中颅窝的咽旁颞下区巨大肿瘤安全而彻底的手术进路.利用颞部切口可充分暴露中颅窝底和颞下窝以及颌下进路显露咽旁区解剖的特点,联合进路切除2例咽旁颞下区巨大肿瘤.2例侵犯中颅窝底的咽旁颞下区肿瘤顺利切除,患者术中组织损伤、出血量相对较少,术后无严重并发症.[结论]颞部-颌下联合进路适合于侵犯中颅窝底的咽旁颞下区肿瘤的手术切除.     

Protection of chickens against highly lethal H5N1 and H7N1 avian influenza viruses with a recombinant fowlpox virus co-expressing H5 haemagglutinin and N1 neuraminidase genes

Inactivated whole avian influenza virus (AIV) vaccine provides protection against homologous haemagglutinin (HA) subtype virus, but poor protection against a heterologous HA virus. Moreover, it induces chickens to produce antibodies to cross-reactive antigens, especially nucleoprotein, which is limits AIV serological surveillance. In this study, a recombinant fowlpox virus co-expressing HA (H5 subtype) and NA (N1 subtype) genes of AIV was evaluated for its ability to protect chickens against intramuscular challenge with a lethal dose of highly pathogenic (HP) AIV. Susceptible chickens were also vaccinated by wing-web puncture with the parent fowlpox vaccine virus. Following challenge 4 weeks later with HPAIV, all chickens vaccinated with recombinant virus were protected, while the chickens vaccinated with either the unaltered parent fowlpox vaccine virus or unvaccinated controls experienced 100% mortality following challenge. This protection was accompanied by the high levels of specific antibody to the respective components of the recombinant vaccine. The above results showed that rFPV-HA-NA could be a potential vaccine to replace current inactivated vaccines for preventing AI.     

经直肠超声引导前列腺穿刺活检203例临床分析

目的评估经直肠超声引导的前列腺六针穿刺活检在前列腺癌及前列腺其他疾病的诊断和鉴别诊断的价值。方法对指肛检查阳性，血清PSA〉4pg／L及经直肠超声检查前列腺声像图异常怀疑有占位性病变的203人进行经直肠超声引导的前列腺穿刺活检。结果穿刺活检的203例病理结果：良性前列腺增生（BPH）104例占51．24％，前列腺癌（PCa）95例占46．80％，前列腺结核及前列腺平滑肌肉瘤各2例，分别占0．98％。结论经直肠超声引导的前列腺穿刺活检其操作简单，病人痛苦小，并发症少，较安全。在前列腺癌及其他前列腺疾病的诊断与鉴别诊断中有重要的临床价值。     

辨证治疗特发性水肿43例疗效观察

特发性水肿是一种原因不明的综合征.在祖国医学属水肿.郁证范畴.近几年笔者采用辨证论治治疗本病43例,取得满意疗效,现报告如下.     

Genetic polymorphism of MHC class III and GLO in Chinese Yao nationality

Yao nationality is one of the minority nationalities living mainly in South China (Guangxi Province). The purpose of this study was to provide data of MHC classI and GLO in Chinese Yao nationality and the different genetic background of Yao and Han nationality, the latter representing the major nationality in China. The genetic polymorphism of MHC classI and GLO in Chinese Yao nationality was determined. Previously the Japanese were considered to have the lowest C*₂C frequencies (0.9386), but now we ascertained that the Yao have the lowest C2*C frequencies (0.9336). The data concerning gene frequencies of Yao are presented. They were also compared with the available data of Han.     

慢性丙型肝炎患者丙型肝炎病毒核酸与IgM抗体关系的研究

本文检测了１４０例丙型肝炎病毒（ＨＣＶ）抗体（抗－ＨＣＶ）阳性的慢性丙型肝炎（ＣＨＣ）的ＨＣＶ核酸（ＨＣＶＲＮＡ）和ＩｇＭ抗体（抗－ＨＣＶＩｇＭ）两项指标。结果表明，原始诊断为不同临床型的肝炎（ＨＣ）患者，８年随访时，ＨＣＶＲＮＡ和抗－ＨＣＶＩｇＭ阳性率分别为８０．７％和９０．７％（ｕ＝２．３９Ｐ＜０．０５）．在原始诊断不同临床型ＨＣ转慢者中，上述两项指标均未发现统计学上的差别（均为Ｐ＞０．０５）。ＨＣＶＲＮＡ与抗－ＨＣＶＩｇＭ配对比较，符合率为７８．６％。基因分型初步结果表明，河北省固安ＨＣＶ以基因Ⅱ型为主。本研究提示，随访８年的ＣＨＣ患者绝大多数仍有传染性；本文方法检测的抗－ＨＣＶＩｇＭ不能代表早期感染标志，但代表慢性感染活动化或带毒，所以，在不具备检测ＨＣＶＲＮＡ的地方更具有实用价值．     

全植入式药泵行肝血管灌注治疗晚期肝癌

对２４例不能切除的晚期肝癌采用完全植入式药泵行肝动脉和门静脉双灌注化疗。结果：部分缓解（ＰＲ）１５例（６２．５％），稳定（Ｓ）８例（３３．３％），进展（Ｐ）１例。平均生存期为９．１７月，半年生存率为６６．７％，１年为２５％。在ＡＦＰ＞４００μｇ／Ｌ的１０例中，５例下降。