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目的 前房注射卡波姆建立大鼠高眼压模型,观察卡波姆升眼压效果及对大鼠眼前节和视网膜的影响。方法 随机选取30只SD大鼠,注射前3 d早晚测量基线眼压。右眼定为实验眼,左眼定为对照眼,右眼放出房水后将30 μL的5 g·L-1卡波姆混悬液注入前房,每日早10时、晚22时在大鼠清醒状态下测量眼压。每周进行双眼眼前节照相并对比。4周末处死26只大鼠(另4只持续观察眼压变化至注射后9周)并取双眼眼球行HE染色,观察实验眼与对照眼视网膜形态,对比视网膜厚度及房角形态。结果 注射前,实验眼白天和夜间眼压分别为(11.10±0.90)mmHg(1 kPa=7.5 mmHg)和(11.92±1.07)mmHg,对照眼分别为(11.22±1.07)mmHg和(11.76±1.08)mmHg;实验眼与对照眼相比,白天、夜间眼压差异均无统计学意义(均为 P>0.05);白天与夜间眼压相比,实验眼、对照眼差异均有统计学意义(均为P<0.05)。卡波姆在前房中呈现出弥散型和沉积型两种存在方式,弥散型和沉积型大鼠1周内眼压分别为(17.83±3.54)mmHg和(13.00±1.55)mmHg,两者相比差异具有统计学意义(P<0.05)。注射后第1天至第19天,实验眼与对照眼白天眼压相比差异均具有统计学意义(均为P<0.05);注射后第1天至第27天,实验眼与对照眼夜间眼压相比差异均具有统计学意义(均为P<0.05)。实验眼视网膜形态发生改变,注射后4周视网膜厚度为(254.70±21.80)μm,与对照眼的(346.73±24.63)μm相比,差异有统计学意义(P=0.00)。实验眼前房充满卡波姆及虹膜的混合成分,紧贴角膜内皮并延伸至房角,堵塞小梁网结构,正常虹膜形态消失;对照眼房角形态正常。结论 前房注射卡波姆建立大鼠高眼压模型,可维持高眼压4周以上,昼夜眼压差异较为明显,夜间眼压较白天更高,4周后视网膜出现高眼压损伤后的表现。  相似文献   
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Tuberculosis (TB) remains one of a major health problem worldwide. Tuberculosis vaccine research has made an extraordinary progress over the past few years. However, there is still no replacement for the Bacillus Calmette‐Guérin vaccine, the only TB vaccine licensed for human use. Therefore, the discovery and development of new TB vaccines remains a priority. This article discusses current strategies used to diversify TB vaccines and includes discussion of the status of efforts to improve protection against Mycobacterium tuberculosis (M tb) infection or TB disease by developing new and safe TB vaccines. This article also highlights the current research efforts in immune‐enhancing approaches to improve vaccination efficacy. The development of more effective TB vaccines might have significant impact on global TB control.  相似文献   
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Melatonin receptors play important roles in the regulation of circadian and seasonal rhythms, sleep, retinal functions, the immune system, depression, and type 2 diabetes development. Melatonin receptors are approved drug targets for insomnia, non‐24‐hour sleep‐wake disorders, and major depressive disorders. In mammals, two melatonin receptors (MTRs) exist, MT1 and MT2, belonging to the G protein‐coupled receptor (GPCR) superfamily. Similar to most other GPCRs, reliable antibodies recognizing melatonin receptors proved to be difficult to obtain. Here, we describe the development of the first monoclonal antibodies (mABs) for mouse MT1 and MT2. Purified antibodies were extensively characterized for specific reactivity with mouse, rat, and human MT1 and MT2 by Western blot, immunoprecipitation, immunofluorescence, and proximity ligation assay. Several mABs were specific for either mouse MT1 or MT2. None of the mABs cross‐reacted with rat MTRs, and some were able to react with human MTRs. The specificity of the selected mABs was validated by immunofluorescence microscopy in three established locations (retina, suprachiasmatic nuclei, pituitary gland) for MTR expression in mice using MTR‐KO mice as control. MT2 expression was not detected in mouse insulinoma MIN6 cells or pancreatic beta‐cells. Collectively, we report the first monoclonal antibodies recognizing recombinant and native mouse melatonin receptors that will be valuable tools for future studies.  相似文献   
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Increasing evidence suggests that human epidermal melanocytes play an important role in the skin immune system; however, a role of their pigmentation in immune and inflammatory responses is poorly examined. In the study, the expression of Toll‐like receptor 4 (TLR4) and inflammatory cytokines and chemokines by cultured normal melanocytes derived from lightly and darkly pigmented skin was investigated after cell stimulation with lipopolysaccharide (LPS). The basal TLR4 mRNA level in heavily pigmented cells was higher as compared to their lightly pigmented counterparts. Melanocyte exposure to LPS upregulated the expression of TLR4 mRNA and enhanced the DNA‐binding activity of NF‐κB p50 and p65. We found substantial differences in the LPS‐stimulated expression of numerous genes encoding inflammatory cytokines and chemokines between the cells with various melanin contents. In lightly pigmented melanocytes, the most significantly upregulated genes were nicotinamide phosphoribosyltransferase (NAMPT/visfatin), the chemokines CCL2 and CCL20, and IL6, while the genes for CXCL12, IL‐16 and the chemokine receptor CCR4 were the most significantly upregulated in heavily pigmented cells. Moreover, the lightly pigmented melanocytes secreted much more NAMPT, CCL2 and IL‐6. The results of our study suggest modulatory effect of melanogenesis on the immune properties of normal epidermal melanocytes.  相似文献   
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