Double deficiency of cathepsin B and L in the mouse pancreas alters trypsin activity without affecting acute pancreatitis severity

BackgroundPremature intracellular trypsinogen activation has long been considered a key initiator of acute pancreatitis (AP). Cathepsin B (CTSB) activates trypsinogen, while cathepsin L (CTSL) inactivates trypsin(ogen), and both proteins play a role in the onset of AP.MethodsAP was induced by 7 hourly intraperitoneal injections of cerulein (50 μg/kg) in wild-type and pancreas-specific conditional Ctsb knockout (Ctsb^Δpan), Ctsl knockout (Ctsl^Δpan), and Ctsb;Ctsl double-knockout (Ctsb^Δpan;Ctsl^Δpan) mice. Pancreatic samples were collected and analyzed by histology, immunohistochemistry, real-time PCR, and immunoblots. Trypsin activity was measured in pancreatic homogenates. Peripheral blood was collected, and serum amylase activity was measured.ResultsDouble deletion of Ctsb and Cstl did not affect pancreatic development or mouse growth. After 7 times cerulein injections, double Ctsb and Ctsl deficiency in mouse pancreases increased trypsin activity to the same extent as that in Ctsl-deficient mice, while Ctsb deficiency decreased trypsin activity but did not affect the severity of AP. Ctsb^Δpan;Ctsl^Δpan mice had comparable serum amylase activity and histopathological changes and displayed similar levels of proinflammatory cytokines, apoptosis, and autophagy activity compared with wild-type, Ctsb^Δpan, and Ctsl^Δpan mice.ConclusionDouble deletion of Ctsb and Ctsl in the mouse pancreas altered intrapancreatic trypsin activity but did not affect disease severity and inflammatory response after cerulein-induced AP.     

Assisting students with autism to cooperate with their peers to perform computer mouse collaborative pointing operation on a single display simultaneously

The purpose of this study was to provide students with autism spectrum disorder (ASD) the chance to cooperate with their peers to perform computer mouse collaborative pointing operation. In this study, we adopted the Single Display Groupware (SDG) concept to develop the Multiple Cursor Collaborative Operating Program (MCCOP) software, which allows multiple users to operate a single computer simultaneously without interfering with each other. With the implementation of MCCOP software, users control their own cursors to perform a function in their respective cursor moving areas on a single display. A collaborative pointing test software (CPTS) program was designed in this experiment to evaluate participants’ collaborative pointing performance. This study adopted an ABAB design, and the experimental results show that all participants significantly increased their collaborative pointing performance during the intervention phase, compared to the baseline phase. Practical and developmental implications of the findings are discussed.     

Infective Endocarditis Due to Treponema pallidum: A Case Diagnosed Using Polymerase Chain Reaction Analysis of Aortic Valve

Syphilis is a sexually transmitted disease caused by Treponema pallidum. Syphilitic aortitis might coexist in a dysfunctional aortic valve, but the etiology remains unclear, because microbiological diagnosis is difficult. A 62-year-old man with low-grade fever was diagnosed with aortitis and infective endocarditis, due to Treponema pallidum infection, using polymerase chain reaction analysis. This case suggests that syphilis might cause infective endocarditis.     

鼠巨细胞病毒感染C57BL/6小鼠急性肝炎动物模型的建立与鉴定

目的：建立鼠巨细胞病毒（MCMV）感染C57BL/6小鼠急性肝炎模型并对其感染特点进行分析及鉴定。方法：将24 只C57BL/6小鼠随机分为阴性对照组（n =12）及病毒感染组（n =12），病毒感染组腹腔注射1.0×106 PFU（200 μL）MCMV悬液，阴性对照组注射等体积小鼠胚胎成纤维细胞（MEF）悬液。于感染后第3天和第7天取外周血分离血清检测谷丙转氨酶（ALT）及谷草转氨酶（AST）。同时进行肝组织病毒分离、组织病理学及MCMV IE和M55基因、细胞因子白细胞介素-6（IL-6）、白细胞介素-1β（IL-1β）、肿瘤坏死因子α（TNF-α）的检测。结果：病毒感染组肝组织匀浆病毒分离均为阳性，肝炎发生率为100%。在感染后第3天即发生肝炎病理改变，病毒感染组血清ALT及AST较阴性对照组明显升高（P ＜0.01）；病毒感染组肝脏HE染色第3天可见局灶性炎性细胞浸润及肝脏点灶状坏死，持续至第7天，Ishak评分较阴性对照组明显升高（P ＜0.01）；在感染后第3天病毒感染组肝组织内可检测到MCMV IE及M55基因，且在感染后第7天仍可测得IE基因；感染后第3天及第7天病毒感染组炎性细胞因子IL-6、TNF-α及IL-1β mRNA表达水平明显升高（P ＜0.05）。 结论：成功建立MCMV感染C57BL/6小鼠急性动物肝炎模型，其感染表现主要集中在急性感染前期。     

小檗碱通过影响糖原结构调节肝糖代谢研究

目的探讨小檗碱调节糖原代谢的机制及对糖原结构的影响。方法采用自发型糖尿病模型db/db小鼠作为疾病模型鼠,考察小檗碱对db/db小鼠血糖水平的影响;提取小鼠的肝糖原进行体积排阻色谱(SEC)和透射电镜(TEM)分析,考察小檗碱对db/db小鼠肝糖原的结构影响,并探讨其影响机制。结果小檗碱可以显著性降低db/db小鼠的空腹血糖,降低db/db小鼠血清胰岛素水平;改善db/db小鼠肝糖原的结构不稳定性;降低db/db小鼠肝组织中糖原磷酸化酶(GP)、糖原脱分支酶(GDBE)和环磷酸腺苷(cAMP)表达水平,降低血清胰高血糖素水平。结论小檗碱可以调控cAMP/GP信号通路,改善db/db小鼠的肝糖原结构,修复受损糖原结构,这可能是其调节肝糖代谢,改善糖尿病症状的机制之一。     

NRP-1单克隆抗体对乳腺癌裸鼠移植瘤生长的影响

 目的 探讨NRP-1单克隆抗体（NRP-1 MAb）的特异性，以及不同剂量的NRP-1 MAb治疗乳腺癌裸鼠移植瘤的疗效。方法 Western blot和共聚焦免疫荧光法检测NRP-1 MAb是否识别MCF7细胞上NRP-1蛋白。将MCF7细胞接种于BALB/c裸鼠皮下建立乳腺癌细胞移植瘤模型，并进行瘤组织传代。传代的肿瘤体积生长至300~500 mm3时，随机分为对照组、NRP-1 MAb低剂量组、中剂量组和高剂量组，每组6只，给药7次。观察荷瘤裸鼠一般状况，测量瘤体大小及裸鼠体重。实验结束时剥离瘤体称重，提取组织蛋白，Western blot检测组织中VEGF蛋白和NRP-1蛋白的表达量。结果 NRP-1MAb成功识别MCF7细胞上的NRP-1蛋白；NRP-1 MAb能够有效抑制MCF7细胞裸鼠移植瘤的生长，低剂量组（1 mg/kg）抑瘤率为47.01%，中剂量组（5 mg/kg）抑瘤率为65.70%，高剂量组（10 mg/kg）抑瘤率为69.19%。。结论 NRP-1 MAb能够识别并有效结合MCF7细胞膜上的NRP-1蛋白，且可抑制MCF7细胞移植瘤的生长，NRP-1 MAb抑制移植瘤的增长可能与下调NRP-1和VEGF表达有关。