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51.
Alpha-lipoic acid (α-LA) was evaluated in this study for its molecular mechanisms against liver oxidative damage and inflammatory responses induced by aflatoxin B1 (AFB1). Birds were randomly allocated into four groups with different diets for three weeks: a basal diet, a 300 mg/kg α-LA supplementation in a basal diet, a diet containing 74 μg/kg AFB1, and 300 mg/kg α-LA supplementation in a diet containing 74 μg/kg AFB1. In the AFB1 group, the expression of GSH-PX mRNA was down-regulated (p < 0.05), and the levels of lipid peroxide and nitric oxide were increased (p < 0.05) in the chicken livers compared to those of the control group. Additionally, the mRNA level of the pro-inflammatory factor interleukin-6 was up-regulated significantly (p < 0.05), the protein expressions of both the nuclear factor kappa B (NF-κB) p65 and the inducible nitric oxide synthase were enhanced significantly (p < 0.05) in the AFB1 group. All of these negative effects were inhibited by α-LA. These results indicate that α-LA may be effective in preventing hepatic oxidative stress, down-regulating the expression of hepatic pro-inflammatory cytokines, as well as inhibiting NF-κB expression. 相似文献
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Rickettsia heilongjiangensis, the causative agent of far eastern spotted fever, is an obligate intracellular gram-negative bacterium that belongs to the spotted fever group rickettsiae. To understand the evolution and pathogenesis of R. heilongjiangensis, we analyzed its genome and compared it with other rickettsial genomes available in GenBank. The R. heilongjiangensis chromosome contains 1333 genes, including 1297 protein coding genes and 36 RNA coding genes. The genome also contains 121 pseudogenes, 54 insertion sequences, and 39 tandem repeats. Sixteen genes encoding the major components of the type IV secretion systems were identified in the R. heilongjiangensis genome. In total, 37 β-barrel outer membrane proteins were predicted in the genome, eight of which have been previously confirmed to be outer membrane proteins. In addition, 266 potential virulence factor genes, seven partially deleted antibiotic resistance genes, and a genomic island were identified in the genome. The codon usage in the genome is compatible with its low GC content, and the amino acid usage shows apparent bias. A comparative genomic analysis showed that R. heilongjiangensis and R. japonica share one unique fragment that may be a target sequence for a diagnostic assay. The orthologs of 37 genes of R. heilongjiangensis were found in pathogenic R. rickettsii str. Sheila Smith but not in non-pathogenic R. rickettsii str. Iowa, which may explain why R. heilongjiangensis is pathogenic. Pan-genome analysis showed that R. heilongjiangensis and 42 other rickettsiae strains share 693 core genes with a pan-genome size of 4837 genes. The pan-genome-based phylogeny showed that R. heilongjiangensis was closely related to R. japonica. 相似文献
54.
基于ZigBee定位与无线数据传输技术,设计了一种针对养老机构的老年人移动体征监测系统。该系统可实现体征(脉搏、心电、血氧)监测、人体定位与紧急情况报警。基于脉搏信号的移动采集与存储实验验证了该系统的有效性,脉搏测量范围为(50-170)次/分,测量平均误差小于3%,定位平均误差小于4 m,系统数据传输速率为250 kbps。该系统可有效实时地对养老机构中的老年人的健康与安全状况进行监护,对老年人生命安全保障具有重要意义。 相似文献
55.
BackgroundThe purpose of this study was to determine the association of the neutrophil-to-lymphocyte ratio (NLR) measured at the time of admission to intensive unit (ICU) with acute kidney injury (AKI) in patients with sepsis and septic shock. In addition, we investigated whether the NLR affects in-hospital mortality in septic AKI patients.MethodsIn this retrospective study, a total of 222 adult patients with sepsis and septic shock were included, who were admitted to the ICU of Zhongnan Hospital of Wuhan University from January 2015 to December 2017. Sepsis and septic shock were diagnosed based on sepsis-3 consensus. AKI was diagnosed according to the KDIGO-AKI criteria. The primary outcome of the study was septic AKI. The secondary endpoint was in-hospital mortality of patients with septic AKI.Results132 patients (59.46%) had AKI, and 64 (28.83%) died, of whom 55 (41.67%) in the AKI group and 9 (10.00%) in the non-AKI group. The NLR of the AKI group was significantly higher than that of the non-AKI group, and there was a statistically significant difference between the two groups (P < 0.001). Multivariate logistic regression analysis suggested that the NLR was independent predictors of septic AKI (OR = 1.047, 95% CI: 1.005–1.091, P = 0.026). The ROC curve showed that the AUC of the NLR for predicting septic AKI was 0.656 (95% CI 0.584–0.728, P < 0.001) and the cutoff value was 17.11 (sensitivity, 62.1%; specificity, 68.9%). However, no correlation was found between the NLR and in-hospital mortality in septic AKI patients.ConclusionNLR, a laboratory variable that is simple, widely available and inexpensive, was associated with the development of septic AKI and may be potential for risk stratification of septic AKI. 相似文献
56.
作者发现了一个新的肿瘤标志物MA153,其化学结构为Mu-GlcNAc(粘蛋白1-N-乙酰氨基葡萄糖),它可与单克隆抗体Ma695和相关Aptamer(适配体MA153-A)形成Ma695-Mu-GlcNAc-MA153-A式的夹心反应。临床血清学检测表明,Mu-GlcNAc存在于癌症患者血中,以1U/mL为正常界值,Mu-GlcNAc的肿瘤特异度达95%,癌症检出的灵敏度对乳腺癌、胰腺癌、肝癌、肺癌、食管癌、口腔癌、结肠癌、胆管癌、卵巢癌、宫颈癌、子宫癌,分别为80%、74%、68%、70%、75%、50%、60%、55%、70%、64%、60%。本研究资料显示,Mu-GlcNAc是一个新的良好广谱肿瘤标志物。 相似文献
57.
2020年7月全球共监测到传染病63种,涉及217个国家和地区。 除流感外,涉及国家和地区数量位于前5位的传染病分别为新型冠状病毒肺炎(217个)、登革热(35个)、麻疹(15个)、霍乱(8个)和基孔肯雅热(8个)。 病死率位于前4位的传染病分别为埃博拉病毒病(43.1%)、鼠疫(21.9%)、拉沙热(20.8%)和新型冠状病毒肺炎(4.0%)。 死亡病例数位于前5位的传染病分别为新型冠状病毒肺炎、霍乱、登革热、麻疹和埃博拉病毒病。 亚洲主要流行新型冠状病毒肺炎和登革热;非洲主要流行新型冠状病毒肺炎、埃博拉病毒病、鼠疫、霍乱、黄热病、拉沙热和麻疹;美洲主要流行新型冠状病毒肺炎和登革热;欧洲主要流行新型冠状病毒肺炎和麻疹。 相似文献
58.
目的 建立测定慢性粒细胞白血病(chronic myelogenous leukemia, CML) 患者血浆帕纳替尼浓度的高效液相色谱- 串联质谱法(HPLC-MS/MS),并应用于帕纳替尼血药浓度日常监测,为帕纳替尼合理使用提供实验室依据。方法 采用含内标(帕纳替尼-d8)的甲醇对患者血浆进行沉淀蛋白处理。色谱柱为Ultimate XB-C18,柱温60℃,流动相为甲醇相(0.1% 甲酸)和水相(0.1% 甲酸和2 mmol/L 乙酸铵),梯度洗脱。质谱检测方式为电喷雾离子阱正离子模式,MRM 扫描,同时监测帕纳替尼m/z 533.1>260.1 和帕纳替尼-d8 m/z 541.2>260.1。采用内标法定量,以帕纳替尼和帕纳替尼-d8 峰面积比为定量依据,计算血浆帕纳替尼浓度,并分别对其线性、专属性、精密度、准确度及稳定性进行考察。结果 帕纳替尼浓度在(1 ~ 250) ng/ml 范围内与峰面积线性关系良好,Y = 0.019 3X + 0.028 4 (r= 0.999 1)。专属性较好,血浆中的内源性物质不干扰帕纳替尼及其内标的测定;日内及日间RSD 均小于5%;相对回收率为100.91%~105.18%;室温放置稳定性及冻融稳定性RSD 均小于5%。结论 该文建立的HPLC-MS/MS 法,前处理简单,特异度及灵敏度高,能准确、快速地检测血浆帕纳替尼浓度,适合慢性粒细胞白血病患者帕纳替尼血药浓度的日常监测。 相似文献
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60.
Feng-Ping Zhou Cheng-Cheng Wang Hua-Ping Du Shan-Bo Cao Jin Zhang 《World Journal of Clinical Cases》2020,8(22):5618-5624
BACKGROUNDPrimary myelofibrosis (PMF) is a myeloproliferative neoplasm (MPN) characterized by recurrent mutations in the JAK2, CALR, and MPL genes. The CALR and MPL co-mutation is very rare. To our knowledge, no more than five cases have been reported. Here, we report a case of PMF in which a CALR and MPL co-mutation was detected by next-generation sequencing (NGS) technology, and a literature review was performed.CASE SUMMARYA 73-year-old woman was admitted to our hospital in 2018 due to abdominal distension. The patient had splenomegaly, lymphadenopathy, leukopenia, anemia, and immature granulocytes in peripheral blood. There were dacrocytes and atypical megakaryocytes in bone marrow, and megakaryocytic proliferation was very active, accompanied by reticulin fibrosis grade 2. By NGS analysis of the bone marrow sample, we detected mutations in CALR, MPL, and PIK3RI, while JAK2 V617F and BCR-ABL were negative. Therefore, the patient was diagnosed with PMF and received oral ruxolitinib. However, the spleen and hematologic responses were poor. We review the literature, analyze previous reports of the mutation sites in our patient and differences between our patient and other reported cases of co-mutated CALR and MPL genes, and discuss the reason why the CALR and MPL co-mutations are rare and possible mechanisms and their impact on the prognosis of patients.CONCLUSIONCALR and MPL mutations can be concurrent in MPN, but they are rare. The use of NGS may help to identify more patients with co-mutated CALR and MPL genes. This will help to further explore the mechanism and its impact on these patients to develop appropriate treatment strategies. 相似文献