Orexin A decreases lipid peroxidation and apoptosis in a novel hypothalamic cell model

Current data support the idea that hypothalamic neuropeptide orexin A (OxA; hypocretin 1) mediates resistance to high fat diet-induced obesity. We previously demonstrated that OxA elevates spontaneous physical activity (SPA), that rodents with high SPA have higher endogenous orexin sensitivity, and that OxA-induced SPA contributes to obesity resistance in rodents. Recent reports show that OxA can confer neuroprotection against ischemic damage, and may decrease lipid peroxidation. This is noteworthy as independent lines of evidence indicate that diets high in saturated fats can decrease SPA, increase hypothalamic apoptosis, and lead to obesity. Together data suggest OxA may protect against obesity both by inducing SPA and by modulation of anti-apoptotic mechanisms. While OxA effects on SPA are well characterized, little is known about the short- and long-term effects of hypothalamic OxA signaling on intracellular neuronal metabolic status, or the physiological relevance of such signaling to SPA. To address this issue, we evaluated the neuroprotective effects of OxA in a novel immortalized primary embryonic rat hypothalamic cell line. We demonstrate for the first time that OxA increases cell viability during hydrogen peroxide challenge, decreases hydrogen peroxide-induced lipid peroxidative stress, and decreases caspase 3/7 induced apoptosis in an in vitro hypothalamic model. Our data support the hypothesis that OxA may promote obesity resistance both by increasing SPA, and by influencing survival of OxA-responsive hypothalamic neurons. Further identification of the individual mediators of the anti-apoptotic and peroxidative effects of OxA on target neurons could lead to therapies designed to maintain elevated SPA and increase obesity resistance.     

Nerve injury induces the expression of syndecan-1 heparan sulfate proteoglycan in peripheral motor neurons

Heparan sulfate proteoglycans play important roles in embryogenesis, including the development of the central nervous system. However, their function in nerve regeneration is not yet understood. We previously reported that nerve injury induces the expression of heparan sulfate glycosaminoglycans and syndecan-1, a heparan sulfate proteoglycan, in injured hypoglossal motor neurons. In this study, we examined the expression of syndecan family members, including syndecan-1, in injured hypoglossal motor neurons after hypoglossal nerve axotomy. We could not detect any changes in expression after axotomy, except for syndecan-1. The expression of syndecan-1 was markedly increased on post-operative day 7. Syndecan-1 was localized not only in the cell bodies of hypoglossal motor neurons, but also in the injured hypoglossal nerve, and it accumulated in the terminals of regenerating fibers. Similarly, facial nerve axotomy and vagus nerve axotomy induced the expression of syndecan-1 in the facial nucleus, dorsal nucleus of vagus and ambiguous nucleus, respectively. However, sciatic nerve axotomy induced very little syndecan-1 expression in injured spinal motor neurons. These results suggest that syndecan-1 may have a crucial role in the survival of injured motor neurons and in nerve regeneration after injury. Our observations also reveal the diversity of peripheral motor neurons.     

Morphologic heterogeneity of renal light-chain deposition disease

Light-chain deposition disease (LCDD) of the kidney is defined as deposition of monotypic light chains (LC) within glomerular (GBM) and tubular (TBM) basement membranes. The morphologic features of pure renal LCDD have been presented only in case reports or small series. The aim of this study was to perform a comprehensive evaluation of the light (LM), immunofluorescence (IF), and electron microscopic (EM) features of pure renal LCDD in a large series of biopsies. Out of 46 cases assembled, 42 had multiple myeloma, 2 had monoclonal gammopathy of unknown significance, and in 2 patients no lymphoproliferative disease was identified. The most common LM lesion of LCDD, nodular glomerulosclerosis, was present in only 14 (30%) cases. GBM and/or TBM thickening was found in 3 (6%), mild to moderate mesangial matrix increase in 12 (23%), and unremarkable glomeruli and tubules were seen in 15 (32%) cases. Forty-two had IF and 40 (92%) showed characteristic linear LC immunoreactivity (24 kappa, 16 lambda) along GBM and/or TBM. Among 39 cases in which IF and EM was available, 25 (64%) were positive by both. Two (6%) were negative by IF, but had deposits by EM. In 12 (30%) with immunoreactivity to LC (4 kappa, 8 lambda), no deposits were identified ultrastructurally. This study shows heterogeneous LM lesions in pure LCDD cases. LM alone may be suspicious but not diagnostic of LCDD. Immunofluorescence is more sensitive than EM for detection of LC for the definitive diagnosis of LCDD. This study supports the importance of utilizing kappa and lambda stains in the routine IF panel for diagnosis of LCDD.     

Nitroxide‐Mediated Radical Polymerization of N‐tert‐Butylacrylamide

The nitroxide‐mediated polymerization of N‐tert‐butylacrylamide (TBAM) in DMF at 120 °C using SG1/DEPN and AIBN has been investigated. Linear growth in number‐average molecular weight ( ) versus conversion and narrow molecular weight distributions (MWDs) with high livingness were obtained up to ≈8 000 g · mol^?1. For higher molecular weights, the MWDs gradually became broader with low molecular weight tailing, and deviated downwards from theoretical values. Quantitative analyses of MWDs, along with specifically designed conventional radical polymerizations at 120 °C, were consistent with chain transfer to monomer limiting the attainable . This finding can be equally applied to existing literature polymerizations of TBAM.

     

Interaction between immunoglobulin allotypes and NK receptor genes in diabetes post-hepatitis C virus infection

Genetic interactions between natural killer (NK) cells immunoglobulin-like receptor (KIR) genes and immunoglobulin allotypes have been previously reported in type 2 diabetes mellitus (DM) patients. Puerto Rican Americans with a history of intravenous drug use who developed DM following HCV infection (n = 32) were compared to individuals infected with HCV without diabetes (n = 121) and to DM non-infected individuals (n = 95). Subjects were genotyped for KIRs and immunoglobulin allotypes. We found interactions of immunoglobulin allotypes KM3/KM3 with NK inhibitory receptors 2DL3/2DL3, 2DL1 in the absence of 2DS4 associated with susceptibility to DM in HCV infected individuals. These data suggest the possibility that a subset of patients with HCV could have an immune-mediated component contributing to the development of DM.     

Trace elements, heavy metals and vitamin levels in patients with coronary artery disease

Aim: In the present study, we aimed to assess serum concentrations of zinc (Zn), copper (Cu), iron (Fe), cadmium (Cd), lead (Pb), manganese (Mn), vitamins A (retinol), D (cholecalciferol) and E (α-tocopherol) in patients with coronary artery disease (CAD) and to compare with healthy controls.Methods: A total of 30 CAD patients and 20 healthy subjects were included in this study. Atomic absorption spectrophotometry (UNICAM-929) was used to measure heavy metal and trace element concentrations. Serum α-tocopherol, retinol and cholecalciferol were measured simultaneously by high performance liquid chromatography (HPLC).Results: Demographic and baseline clinical characteristics were not statistically different between the groups. Serum concentrations of retinol (0.3521±0.1319 vs. 0.4313±0.0465 mmol/I, p=0.013), tocopherol (3.8630±1.3117 vs. 6.9124±1.0577 mmol/I, p<0.001), cholecalciferol (0.0209±0.0089 vs. 0.0304±0.0059 mmol/I, p<0.001) and Fe (0.5664±0.2360 vs. 1.0689±0,4452 µg/dI, p<0.001) were significantly lower in CAD patients. In addition, while not statistically significant serum Cu (1.0164±0.2672 vs. 1.1934±0.4164 µg/dI, p=0.073) concentrations were tended to be lower in patients with CAD, whereas serum lead (0.1449±0.0886 vs. 0.1019±0.0644 µg/dI, p=0.069) concentrations tended to be higher.Conclusions: Serum level of trace elements and vitamins may be changed in patients with CAD. In this relatively small study we found that serum levels of retinol, tocopherol, cholecalciferol, iron and copper may be lower whereas serum lead concentrations may be increased in patients with CAD.     

A study of tubercular lymphadenitis: a comparison of various laboratory diagnostic modalities with a special reference to tubercular polymerase chain reaction

Objective: The purpose of our study was to compare various laboratory diagnostic methods, namely histopathological examination, Ziehl-Neelsen (ZN) stain, AFB culture by conventional Lowenstein–Jensen (LJ) method and fluorescence-based mycobacterial growth indicator tube (MGIT) technique and polymerase chain reaction (PCR) in clinically suspected cases of tubercular lymphadenitis. Materials and Methods: A total of 65 lymph nodes biopsied from patients clinically suspected of having tubercular lymph nodes were included. Specimens were processed for AFB culture after NaOH-NALC concentration and inoculation on LJ medium and using the MGIT system. PCR was performed on all specimens using a commercial nested PCR kit targeting IS6110 insertion element of Mycobacterium tuberculosis complex. All lymph node specimens were subjected to histopathological examination. Results: Of the 65 lymph nodes, 37 (56.9%) were positive on MGIT culture and 45 (69.2%) were positive by PCR. Histopathology showed maximum sensitivity (96%) but with compromised specificity (78.5%). PCR showed 90.1% sensitivity and 100% specificity. The mean turnaround time for mycobacterial growth in smear negative specimens was 30 days determined by LJ and 20 days by MGIT techniques. Conclusion: PCR is a rapid and useful method for diagnosis of TB lymphadenitis and definitely increases the positive predictive value of a positive histopathology report. MGIT is better than LJ culture as regards time to positivity and higher yield.     

微量胰岛素对七氟醚吸入麻醉诱导新生大鼠认知功能障碍的预防作用及其可能的作用机制

目的 探讨微量胰岛素对七氟醚吸入麻醉诱导大鼠认知功能障碍的预防作用,及其可能的作用机制。 方法 将60只新生大鼠随机分为对照组（CON）、低剂量胰岛素预防组（LIP）、高剂量胰岛素预防组（HIP）和七氟醚模型组（MOD）,其中预防组和模型组均采用七氟醚诱导构建大鼠认知功能障碍模型。采用Morris水迷宫定向航行实验和空间探索实验评价大鼠的学习和记忆功能; HE染色观察大鼠海马组织病理学变化;流式细胞术检测大鼠海马组织细胞的凋亡情况;RT-PCR检测海马组织雷帕霉素靶蛋白（mTOR）、真核细胞肽链延伸因子2（eEF-2） mRNA表达水平; Western blotting检测脑源性神经营养因子（BDNF）、突触后致密蛋白-95（PSD-95）、突触素-Ⅰ（synapsin-Ⅰ）、钙调蛋白激酶Ⅱα（CaMKⅡα）、mTOR及eEF-2蛋白表达水平。 结果 Morris水迷宫实验结果显示,胰岛素能够显著缩短大鼠逃避潜伏期时间及游泳距离,提高穿越平台次数;流式细胞术结果表明,胰岛素预防组能够显著抑制大鼠脑神经细胞的凋亡,且高剂量胰岛素预防组抑制效果更为明显;RT-PCR 及Western blotting检测发现,模型组大鼠海马组织中mTOR、eEF-2 mRNA和蛋白表达水平显著升高,而BDNF、PSD-95、synapsin-Ⅰ、CaMKⅡα蛋白表达水平显著降低;与模型组相比,胰岛素预防给药组大鼠海马组织中mTOR、eEF2 mRNA和蛋白表达水平显著下调,而BDNF、PSD-95、synapsin-Ⅰ、CaMKⅡα蛋白表达水平明显上调,差异具有统计学意义（P<0.05）。 结论 微量胰岛素可增加认知功能障碍大鼠海马组织中突触相关蛋白的表达,降低其mTOR、eEF-2 mRNA表达水平,预防七氟醚诱导的大鼠认知功能的障碍,其机制可能与调节mTOR-eEF2途径有关。