病毒性心肌炎患儿血清CK—MB与心肌肌钙蛋白I的检测诊断价值

目的研究血清肌酸激酶同工酶（CK—MB）与心肌肌钙蛋白I（cTnI）检测在病毒性心肌炎患儿诊断中的价值。方法将39例病毒性心肌炎患儿作为观察组，以同期行常规体检的39例健康儿童作为对照组，对比两组的cTnI、CK—MB的检测结果，并在观察组内对比cTnI与CK—MB的阳性率。结果观察组患儿发病1～2d时cTnI与CK—MB与对照组均有显著差异：发病7d及14d时观察组cTnI与对照组有显著差异。观察组内患儿发病1～2d时cTnI检测阳性率明显高于CK—MB；7d与14d时cTnI检测的阳性率则显著高于CK—MB．结论cTnI在病毒性心肌类的诊断中均且有较高的特异唐与敏威唐     

Nuclear DNA replication and repair in parasites of the genus Leishmania: Exploiting differences to develop innovative therapeutic approaches

Leishmaniasis is a common tropical disease that affects mainly poor people in underdeveloped and developing countries. This largely neglected infection is caused by Leishmania spp, a parasite from the Trypanosomatidae family. This parasitic disease has different clinical manifestations, ranging from localized cutaneous to more harmful visceral forms. The main limitations of the current treatments are their high cost, toxicity, lack of specificity, and long duration. Efforts to improve treatments are necessary to deal with this infectious disease. Many approved drugs to combat diseases as diverse as cancer, bacterial, or viral infections take advantage of specific features of the causing agent or of the disease. Recent evidence indicates that the specific characteristics of the Trypanosomatidae replication and repair machineries could be used as possible targets for the development of new treatments. Here, we review in detail the molecular mechanisms of DNA replication and repair regulation in trypanosomatids of the genus Leishmania and the drugs that could be useful against this disease.     

Refining the Baveno VI elastography criteria for the definition of compensated advanced chronic liver disease

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Acidic C-terminal tail of the ssDNA-binding protein of bacteriophage T7 and ssDNA compete for the same binding surface

ssDNA-binding proteins are key components of the machinery that mediates replication, recombination, and repair. Prokaryotic ssDNA-binding proteins share a conserved DNA-binding fold and an acidic C-terminal tail. It has been proposed that in the absence of ssDNA, the C-terminal tail contacts the ssDNA-binding cleft, therefore predicting that the binding of ssDNA and the C-terminal tail is mutually exclusive. Using chemical cross-linking, competition studies, and NMR chemical-shift mapping, we demonstrate that: (i) the C-terminal peptide of the gene 2.5 protein cross-links to the core of the protein only in the absence of ssDNA, (ii) the cross-linked species fails to bind to ssDNA, and (iii) a C-terminal peptide and ssDNA bind to the same overall surface of the protein. We propose that the protection of the DNA-binding cleft by the electrostatic shield of the C-terminal tail observed in prokaryotic ssDNA-binding proteins, ribosomal proteins, and high-mobility group proteins is an evolutionarily conserved mechanism. This mechanism prevents random binding of charged molecules to the nucleic acid-binding pocket and coordinates nucleic acid–protein and protein–protein interactions.     

A research for the relationship between human papillomavirus and human uterine cervical carcinoma

Summary Biopsies from 318 cases with squamous cell carcinoma of the uterine cervix, 48 with cervical and vulvar condylomata, 14 with cervical intraepithelial neoplasia (CIN), 34 with chronic cervicitis and 24 with normal cervical epithelium were collected from different geographic regions with different cervical cancer mortalities. The DNA · DNA dot-blot and Southern blot hybridization results show that there is a close relationship between HPV-16 and the uterine cervical squamous cell carcinoma in China. One very interesting observation is that the finding of HPV-16-homologous DNA differs significantly among five geographic regions, and corresponds with the mortalities from cervical cancer of these five regions. HPV-11 was found mainly in benign lesions. The rate of detection of HPV-16 in Chinese women increased from 8.3% in normal cervical epithelium to 20% in chronic cervicitis, 28% in cervical condyloma, 50% in CIN and 60.4% in cervical cancer. It is suggested that HPV-16 infection may be an etiological factor in the development of human cervical carcinoma. From the results of Southern blot hybridization, it appeared that HPV-16 DNA had been integrated into the genome of the host cell in cervical cancer. Whereas the HPV-16 DNA sequence was only present as an episome in normal cervical epithelium and cervical benign lesions. The rate of occurence of E6-E7 genes is the highest (88.9%) compared with that of other subgenomic fragments of HPV-16 in specimens of human cervical cancer in China. This implies that E6 and E7 may be the oncogenic genes of HPV-16 and play an important role in the carcinogenesis of human cervical epithelial cells. The amplification and rearrangement of the c-myc protooncogene are closely associated with the occurrence of cervical cancer. The results presented here revealed that the activated c-myc oncogene may cooperate with HPV-16 in the carcinogenic processes.Abbreviations HPV Human papillomavirus - CIN cervical intraepithelial neoplasia - SSC standard saline citrate     

健康教育对接受干扰素治疗患者生活质量的影响研究

目的：评价健康教育对接受干扰素治疗的慢性肝病患者生活质量的影响。方法：本研究采用自身前后对照试验设计的准试验类研究。60例慢性肝病患者纳入本次研究。健康教育内容包括：自我注射干扰素的方法;介绍慢性肝病性质、疾病传染路径以及疾病诊治,介绍干扰素疗法对其对疾病的影响、注射干扰素后的常见副作用、自我保护和控制副作用方法。将患者随机分为实验组和对照组,每组30例。采用慢性肝炎患者生活质量调查表评价患者生活质量。健康教育连续进行四周,每周一次,每次45分钟。随访连续进行12周。比较两组患者生活质量变化情况。结果：对照组患者的系统症状在接受治疗12周后明显下降;实验组患者在接受本研究干预后,包括腹部症状、活动、焦虑和情绪症状均出现显著降低;而系统症状和疲劳无任何改变。实例组和对照组腹部症状、焦虑和情绪症状存在差异。对照组患者在研究干预前和接受干预12周后的平均生活质量得分分别为154.5和136.9,差异无统计学意义。实例组患者在研究干预前和接受干预12周后的平均生活质量得分从158.6上升至170,差异有统计学意义。在接受健康教育前,两组患者的生活质量得分并无显著差异,但在干预后差异显著。结论：为接受干扰素-α治疗的乙肝和丙肝患者提供持续性健康将大幅提升患者对干扰素疗法的坚持度,降低治疗的副作用,并最终提高患者的生活质量。     

Increased Prevalence of Myocardial Injury in Patients with SARS-CoV-2 Viremia

BackgroundPatients with coronavirus disease 2019 (COVID-19) have a high prevalence of detectable troponin and myocardial injury. In addition, a subset of patients with COVID-19 has detectable severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral loads. The objective of this study was to understand the relationship among SARS-CoV-2 viremia, detectable troponin, and myocardial injury in hospitalized patients with COVID-19.MethodsSARS-CoV-2 plasma viral load was measured in plasma samples drawn from patients hospitalized for COVID-19 at 2 academic medical centers. Baseline characteristics and clinically obtained high-sensitivity cardiac troponin T (hs-cTnT) values were abstracted from the medical record. The main outcome was detectable hs-cTnT (≥6 ng/mL) and myocardial injury (hs-cTnT ≥14 ng/mL; >99th percentile for assay).ResultsA total of 70 hospitalized patients with COVID-19 were included in this study, with 39% females and median age 58 ± 17 years; 21 patients (30%) were found to have detectable SARS-CoV-2 viral load and were classified in the viremia group. Patients with viremia were significantly older than those without viremia. All of the patients with viremia (100%) had detectable troponin during hospitalization compared with 59% of patients without viremia (P = 0.0003). Myocardial injury was seen in 76% of patients with viremia and 38% of those patients without viremia (P = 0.004).ConclusionsHospitalized patients with COVID-19 with SARS-CoV-2 viremia have a significantly higher prevalence of detectable troponin and myocardial injury during their hospitalization compared with patients who did not. This first report of the relationship among SARS-CoV-2 viremia, detectable troponin, and myocardial injury in patients with COVID-19 points to additional mechanistic pathways that require deeper study to understand the complex interplay among these unique findings, cardiovascular outcomes, and mortality in COVID-19.     

重组H9N2禽流感病毒的构建及其在不同细胞中的复制特性

目的利用反向遗传学技术构建具有感染性的H9N2亚型禽流感病毒,并揭示其在不同细胞中的复制特性。方法以A/Quail/Hong Kong/G1/97(H9N2)禽流感病毒基因组RNA为模板,用RT-PCR技术获得该病毒的8条完整基因片段,并分别将它们插入到p HW2000载体上,最终在293T细胞中包装产生重组H9N2病毒。并将重组的H9N2病毒感染不同细胞,观察病毒在不同细胞上的增殖状况来揭示该病毒在不同细胞上的复制特性。结果应用流感病毒8质粒反向遗传学技术,成功获得重组病毒,并揭示了该毒株在不同细胞(A549,MDCK,Vero)中的复制特性,发现A549人肺腺癌细胞更适宜H9N2病毒的正常复制。此外还分析总结了该毒株的与病毒毒力相关的重要位点特征。结论成功建立了H9N2禽流感病毒的反向遗传系统,该系统的建立为在分子水平研究H9N2病毒以及制备H9N2禽流感疫苗提供了依据。