随意跑轮运动对糖尿病大鼠心肌NADPH氧化酶及心脏重塑的影响

目的 观察随意跑轮运动对糖尿病大鼠心肌烟酰胺腺嘌呤二核苷酸磷酸（NADPH）氧化酶调节亚基p47phox及p67phox表达的影响,初步探讨运动训练抑制糖尿病心脏氧化应激及心脏重塑的可能机制。 方法 采用随机数字表法将40只SD大鼠分为正常对照组、模型组及运动组,后2组采用链脲佐菌素进行糖尿病造模。于造模成功1周后正常对照组及模型组大鼠均置于鼠笼内安静饲养,运动组大鼠给予8周（5 d/周）随意跑轮运动。于末次训练结束48 h后取静脉血测定血糖含量,利用超声心动图检测心脏结构及功能,采用Masson染色进行心肌组织病理学观察并检测心肌纤维化指数,将心肌组织匀浆后测定丙二醛（MDA）及活性氧（ROS）含量,采用Western blot技术检测心脏NADPH氧化酶p47phox及p67phox亚基蛋白表达量。 结果 与正常对照组比较,模型组血糖含量升高（P<0.05）,左心室收缩末期直径（LVESD）和左心室舒张末期直径（LVEDD）增加（P<0.05）,左心室射血分数（LVEF）下降（P<0.05）,心肌纤维化指数增加（P<0.05）,MDA及ROS含量升高（P<0.05）,p47phox及p67phox亚基蛋白表达量上调（P<0.05）;与模型组比较,运动组血糖含量降低（P<0.05）,LVESD及LVEDD下降（P<0.05）,LVEF升高（P<0.05）,心肌纤维化指数降低（P<0.05）,MDA及ROS含量下降（P<0.05）,p47phox及p67phox亚基蛋白表达量下调（P<0.05）。 结论 随意跑轮运动能通过抑制NADPH氧化酶调节亚基p47phox及p67phox表达,减轻糖尿病大鼠心脏氧化应激反应,进而抑制心脏重塑并增强心功能。     

Assessment of naturally occurring covalent and total dimer levels in human IgG1 and IgG2

Antibody dimers, two self-associated monomers, have been detected on both recombinantly expressed and endogenous human IgG proteins. Nearly 10 years ago, Yoo et al. (2003) described low levels of IgG2 covalent dimer, in human serum, but did not quantify the levels. Here we quantify the total and covalent dimer levels of IgG2 and IgG1 in human blood, and study the origin of covalent dimer formation. Low levels (<1%) of total IgG1 and IgG2 dimers were measured in freshly prepared human plasma. Both IgG1 and IgG2 covalent dimers were also found in plasma. Whereas IgG1 covalent dimer levels were significantly reduced by steps intended to eliminate artifacts during sample preparation, IgG2 covalent dimer levels remain stable in such conditions. About 0.4% of IgG2 in plasma was in a covalent dimer form, yet very little (<0.03%) of IgG1 covalent dimer could be considered naturally occurring. IgG2 dimer also formed in vitro under conditions designed to mimic those in blood, suggesting that formation occurs in vivo during circulation. Thus, small amounts of covalent IgG2 dimer do appear to form naturally.     

Der p 2 can induce bystander activation of B cells derived from patients with systemic lupus erythematosus

Although many patients with SLE also have allergies, the immunological events triggering the onset and progression of the clinical manifestations of SLE by allergens have yet to be clarified. A total of three autoantigens, phosphoglycerate kinase 1 (PGK-1), triosephosphate isomerase (TIM) and enolase were identified by autologous serum in B cell lysate derived from HDM allergic SLE patients after Der p 2 stimulation. Autoantigen, TRIM-21 expression were also significantly increased in B cells derived from HDM allergic SLE patients. In PBMCs derived from SLE patients, the concentration of anti-PGK-1 was significantly upregulated after Der p 2 stimulation compared to HDM allergic without SLE patients and healthy subjects. Inflammatory related cytokines and chemokines include IL-1β, IL-6, IL-8, CXCL5 could be upregulated after Der p 2 stimulation in PBMCs derived from HDM allergic SLE patients. In conclusion, our data demonstrated that long-term allergen exposure could be a contributing factor in the development of SLE.     

Can Toll-Like Receptor (TLR) 2 be considered as a new target for immunotherapy against hepatitis B infection?

The current literature describes pivotal mechanisms in which hepatitis B virus (HBV) induces liver diseases including inflammation, cirrhosis and hepatocellular carcinoma (HCC). It appears that differences in genetic and immunological parameters between patients and controls may be responsible for inducing the prolonged forms of the infection. Previous studies demonstrated that Toll-Like Receptors (TLRs) play key roles in viral recognition and inducing appropriate immune responses. Therefore, TLRs can be considered as key sensors for HBV recognition and subsequent induction of immune responses against this virus. It has also been shown that the TLR2 detects several microbial PAMPs either in its homodimer form or in a heterodimer with TLR1 or TLR6 and subsequently activates NF-κB in a MYD88 dependent manner. Therefore, defective TLR2 expression may result in impaired immune responses against HBV which is reported in long-term forms of hepatitis B. This review presents the recent data regarding the status and important roles played by TLR2 in HBV recognition and induction or suppression of immune responses against HBV as well as its roles in the pathogenesis of cirrhosis and HCC in prolonged hepatitis B forms.     

Molecular characterisation of Giardia intestinalis assemblages from human isolates at a tertiary care centre of India

Purpose: The aim of the study was to determine the genetic heterogeneity of Giardia intestinalis isolates detected in stool samples of the study population using polymerase chain reaction assay and restriction fragment length polymorphism. We also tried to correlate the association/differences between the clinical symptomatology and infection by different assemblages (genotypes) of G. intestinalis. Materials and Methods: This cross-sectional study was conducted from April 2008 to June 2010. A total of 40 adults (n = 40) and 42 children (n = 42) below the age of 12 years with the clinical suspicion of giardiasis and with the onset of one or more of the following five symptoms, i.e., loose stool, nausea, weight loss, fatigue and foul smelling faeces and confirmed laboratory diagnosis of giardiasis at least once during the current episode of diarrhoea were included in this study. Results: Of the 82 patients (males 66) enrolled in the study, 70 (85%) presented with diarrhoea (56 males) and 12 (15%) without diarrhoea (10 males). Out of 70 diarrheic patients, 61 (87%) had chronic diarrhoea, 8 (11.5%) had acute diarrhoea and 1 (1.5%) had persistent diarrhoea. Of the total patients, 63 (77%) were clinically assessed and were apparently immunocompetent, whereas, 19 (23%) immunocompromised patients had different underlying conditions besides giardiasis. Genotyping identified all 82 (100%) isolates as assemblage B. Conclusion: We found that assemblage B of G. intestinalis presents with all kinds of clinical features ranging from asymptomatic carriage to acute, persistent or chronic diarrhoea.     

Venlafaxine alters microvascular perfusion, [I]-beta-CIT binding and BDI scores in flushing postmenopausal women

Background

Although 70% of postmenopausal women suffer from hot flashes the pathophysiology is poorly understood. The serotonin and noradrenaline reuptake inhibitor (SNRI) venlafaxine provides relief of flushing although the mechanism is unknown and could involve a central effect and/or a peripheral effect. Using single photon emission computed tomography (SPECT) we studied the central serotonin transporter (SERT) in vivo using [¹²³I]-beta-carbomethoxy-3-β-(4-iodophenyl)tropane (beta-CIT) and, as previous studies have shown that reactivity of the skin blood vessels is enhanced in those who flush, we examined cutaneous microvascular perfusion.

Methods

Cutaneous microvascular perfusion was assessed in 31 postmenopausal women, with flushing, using laser Doppler imaging with iontophoresis (LDI + ION), before and after 8 weeks of treatment with venlafaxine. A sub-group of 14 of these women also had SPECT imaging at both time points to evaluate the availability of SERT in the brain. Flush frequency and score was recorded, and Beck Depression Inventory (BDI) II scores were assessed before and after treatment.

Results

Following treatment with venlafaxine, there was a significant reduction in the [¹²³I]-beta-CIT binding ratio, BDI scores, flushing and endothelial dependent perfusion response. [¹²³I]-Beta-CIT reduction was associated with BDI reduction (r² = 0.54; F = 8.8; p = 0.004), but not flushing reduction or perfusion reduction.

Conclusions

Venlafaxine resulted in a decrease in BDI II scores with an associated reduction in [¹²³I]-beta-CIT binding in a group of non-depressed women. It also improved flush frequency and severity which may be as a result of decreases seen in enhanced cutaneous microvascular perfusion.     

Should IFN-γ, IL-17 and IL-2 be considered predictive biomarkers of acute rejection in liver and kidney transplant? Results of a multicentric study

Acute rejection (AR) remains a major challenge in organ transplantation, and there is a need for predictive biomarkers. In the present multicenter study, we prospectively examined a series of biomarkers in liver and kidney recipients. Intracellular expression of IFN-γ, IL-17 and IL-2 and IL-17 soluble production were evaluated both pre-transplantation and post-transplantation (1st and 2nd week, 1st, 2nd and 3rd month). 142 transplant patients (63 liver/79 kidney) were included in the study. Twenty-eight recipients (14 liver/14 kidney) developed AR. Pre- and post-transplantation intracellular expression of %IFN-γ⁺ in CD4⁺CD69⁺ and in CD8⁺CD69⁺ and soluble IL17 identified liver and kidney transplant patients at high risk of AR. Pre-transplantation, %IL-2⁺ in CD8⁺CD69⁺ also identified kidney patients at high risk. We constructed pre- and post-transplantation risk prediction models, based on a composite panel of biomarkers, which could provide the basis for future studies and will be a useful tool for the selection and adjustment of immunosuppressive treatments.     

活性氧与肾纤维化的研究进展

肾纤维化是各种慢性肾疾病进行性发展的主要病理基础,活性氧在肾纤维化的发生和发展中扮演着重要的角色。有关抗氧化治疗肾纤维化的研究较多,N-乙酰半胱氨酸、血管紧张素转换酶抑制剂、氟非尼酮、维生素E等被认为有一定的肾保护作用,这也为肾纤维化的临床防治提供新的研究方向和治疗靶点。