维生素D对非酒精性脂肪性肝病的保护作用

维生素D是一种脂溶性类固醇激素,其除从传统意义上调节钙、磷平衡及骨代谢外,还具有广泛的骨外生物学作用,如参与机体能量代谢和糖、脂代谢.维生素D缺乏可能引起代谢综合征,而非酒精性脂肪性肝病(NAFLD)是代谢综合征在肝脏中的表现形式.有证据显示,维生素D可通过介导胆汁酸代谢、减轻胰岛素抵抗以及改善肝纤维化这3条途径发挥对NAFLD的保护作用.     

自调节根管锉的特性和临床应用评价

根管预备（根管清理和根管成形）是根管治疗的关键步骤。为了达到良好的根管预备目的,各种先进器械和新型材料不断涌现。从标准不锈钢根管锉到旋转镍钛锉系统的相继应用,根管预备的质量和效率得到了大幅的提高;然而这两种临床常用的器械并没有完全达到根管预备的目标,尤其在三维影像上仍存在着明显的缺陷。自调节根管锉（SAF）这种新型镍钛器械的诞生,为根管预备技术带来了突破。其全新的设计克服了传统根管锉在柔韧性和可塑性等方面的不足,其自带的冲洗装置实现了根管冲洗和成形的同步操作,根管清理更为完善。本文就SAF的特性、力学性能和临床应用等研究进展作一综述。     

A study of the PEMT gene in schizophrenia

The phospholipid hypothesis of schizophrenia is becoming popular because of the findings from the niacin flush test, the treatment with polyunsaturated fatty acids (PUFAs), biochemical studies for the phospholipid metabolism pathway and genetic studies of phospholipase A2. The present study attempted to investigate the gene coding for phosphatidylethanolamine N-methyltransferase (PEMT), which is an important enzyme for the synthesis of membrane phospholipids. We recruited 271 Chinese parent-offspring trios of Han descent and detected 3 single nucleotide polymorphisms (SNPs) at the PEMT locus. The transmission disequilibrium test (TDT) showed allelic association for rs464396 (X2=9.4, P=0.002), but not for the other two. The 2-SNP haplotype analysis showed haplotypic association for both the rs936108-rs464396 haplotypes (X2=25.7, d.f.=3, P=0.00001) and the rs464396-rs4244593 haplotypes (X2=17.3, d.f.=3, P=0.0006). The 3-SNP haplotype analysis also showed a haplotypic association (X2=24.4, d.f.=7, P=0.0006). The present results suggest that the PEMT gene may contribute to the etiology of schizophrenia.     

Diethylstilbestrol impaired oogenesis of yellow catfish juveniles through disrupting hypothalamic–pituitary–gonadal axis and germ cell development

Diethylstilbestrol (DES), a non‐steroidal estrogen, has been found to cause altered germ cell development and disordered ovarian development in fish females. However, the mechanisms that might be involved are poorly understood. In this study, female juveniles of yellow catfish (Pelteobagrus fulvidraco) (120 days post‐hatching) were exposed to two doses (10 and 100 ng l^?1) of DES for 28 days. After the endpoint of exposure, decreased ovary weight and gonadosomatic index, as well as various ovarian impairments were observed in response to DES. Besides, DES elevated the mRNA levels of vitellogenin 1 (vtg 1) and estrogen receptor 1 (esr 1) in liver and decreased 17β‐estradiol level in plasma. Correspondingly, suppressed mRNA levels of the key genes in the hypothalamic–pituitary–gonadal axis (such as cyp19a1b, gnrh‐II, fshβ and lhβ in brain and fshr, lhr and cyp19a1a in ovary) after DES exposure were also observed. The declined level of plasma 17β‐estradiol and altered gene expressions of genes in the hypothalamic–pituitary–gonadal axis were thus supposed to be closely related to the disrupted oogenesis in DES‐treated fish. Analyses further demonstrated that, higher concentration of DES elevated the expression ratio of bax/bcl‐2, indicating the enhanced apoptosis occurred in ovary. Moreover, DES upregulated the expressions of genes involved in proliferation (cyclin d1 and pcna), meiotic entry (cyp26a1 and scp3) and meiotic maintenance (dmc1), resulting in arrested oogenesis in catfish. The present study greatly extended our understanding on the mechanisms underlying of reproductive toxicity of DES on fish oogenesis.     

Magnetic control of an electrochemical microfluidic device with an arrayed immunosensor for simultaneous multiple immunoassays

BACKGROUND: Methods based on magnetic bead probes have been developed for immunoassay, but most involve complicated labeling or stripping procedures and are unsuitable for routine use. METHODS: We synthesized magnet core/shell NiFe(2)O(4)/SiO(2) nanoparticles and fabricated an electrochemical magnetic controlled microfluidic device for the detection of 4 tumor markers. The immunoassay system consisted of 5 working electrodes and an Ag/AgCl reference electrode integrated on a glass substrate. Each working electrode contained a different antibody immobilized on the NiFe(2)O(4)/SiO(2) nanoparticle surface and was capable of measuring a specific tumor marker using noncompetitive electrochemical immunoassay. RESULTS: Under optimal conditions, the multiplex immunoassay enabled the simultaneous detection of 4 tumor markers. The sensor detection limit was <0.5 microg/L (or <0.5 kunits/L) for most analytes. Intra- and interassay imprecisions (CVs) were <4.5% and 8.7% for analyte concentrations >5 mug/L (or >5 kunits/L), respectively. No nonspecific adsorption was observed during a series of procedures to detect target proteins, and electrochemical cross-talk (CV) between neighboring sites was <10%. CONCLUSION: This immunoassay system offers promise for label-free, rapid, simple, cost-effective analysis of biological samples. Importantly, the chip-based immunosensor could be suitable for use in the mass production of miniaturized lab-on-a-chip devices and open new opportunities for protein diagnostics and biosecurity.     

苦参碱类生物碱的镇痛作用研究进展

苦参碱类生物碱（包括有苦参碱、氧化苦参碱、氧化槐定碱、槐果碱、氧化槐果碱等）具有镇痛作用,镇痛特征是以中枢性为主、无成瘾性和耐药性,综述其镇痛作用及作用机制研究进展。苦参碱类生物碱的中枢性镇痛作用机制可能是：激活大麻素受体-2和上调电压门控钙离子N-型通道表达,促进抑制性神经递质（γ-氨基丁酸、甘氨酸）合成和释放,下调GAT-1表达,使突触间隙γ-氨基丁酸浓度升高以及上调γ-氨基丁酸-A受体表达,从而增强γ-氨基丁酸能神经功能。γ-氨基丁酸能神经功能的增强可抑制兴奋性神经递质谷氨酸过度表达并下调NMDA受体和蛋白激酶Cγ表达,降低NMDA受体对谷氨酸的兴奋性,从而下调电压门控钙离子L-型通道的表达,抑制钙离子内流,阻滞CaMKⅡ/CREB通路,减轻炎症反应和产生镇痛作用。     

紫正地黄汤联合孟鲁司特钠治疗儿童腺样体肥大疗效及对患儿血清变态反应指标、氧化应激的影响

目的:探讨紫正地黄汤联合孟鲁司特钠治疗儿童腺样体肥大疗效及对血清变态反应指标、氧化应激的影响。方法:选取腺样体肥大患儿100例,按照随机数字表法分为对照组和治疗组,每组各50例。对照组采用孟鲁司特钠治疗,治疗组在对照组基础上给予紫正地黄汤加减。比较两组临床疗效、血清变态反应指标、氧化应激指标及不良反应发生情况。结果:治疗组总有效率96.00%,高于对照组的74.00%,差异有统计学意义(P<0.05)。治疗后,治疗组血清嗜酸性粒细胞阳离子蛋白、嗜酸性粒细胞直接计数及卵清蛋白特异性IgE水平低于对照组,差异有统计学意义(均P<0.05)。治疗后治疗组血清促肾上腺皮质激素、超敏C反应蛋白、降钙素原低于对照组,差异有统计学意义(均P<0.05)。治疗组不良反应发生率2.00%,与对照组的6.00%比较,差异无统计学意义(P>0.05)。结论:紫正地黄汤联合孟鲁司特钠治疗儿童腺样体肥大疗效较好,能明显改善患者变态反应及氧化应激状态,安全性较好。