A PCR based assay for detection and differentiation of African trypanosome species in blood

Direct PCR analysis of trypanosome infected blood samples in the quantities required for large scale epidemiological study has always been problematic. Current methods for identifying and differentiating trypanosomes typically require several species-specific reactions, many of which rely on mouse passaged samples to obtain quality concentrated genomic DNA. As a consequence important epidemiological information may be lost during the sample preparation stage. Here, we report a PCR methodology that reduces processing and improves on the sensitivity of present screening methods. The PCR technique targets the gene encoding the small ribosomal subunit in order to identify and differentiate all clinically important African trypanosome species and some subspecies. The method is more economical, simple, and sensitive than current screening methods, and yields more detailed information, thereby making it a viable tool for large-scale epidemiological studies.     

Comparison of two methods (microscopy and enzyme-linked immunosorbent assay) for the diagnosis of amebiasis

Diagnosis of amebiasis is usually performed on a clinical basis alone in most endemic countries having limited economic resources. This epidemiological study was conducted using modern diagnostic tests for amebiasis in the southeastern region of Turkey, an endemic area for amebiasis. The population of this study included patients with symptomatic diarrhea/dysentery attending both Yuzuncu Yil University, Van and Harran University, Sanliurfa, Turkey. A total of 380 stool specimens were collected and examined for Entamoeba by light microscopy (fresh, lugol, and trichrome staining) and stool antigen detection based- enzyme-linked immunosorbent assay (EIA) test (TechLab Entamoeba histolytica II). 24% (91/380) of stool specimens were positive for E. histolytica/Entamoeba dispar trophozoites/cysts microscopically using trichrome staining. 13% (51/380) of the stool specimens were found to be positive for E. histolytica by the EIA test, including 15% (14/91) of microscopy (+) stool specimens and 13% (37/289) of microscopy (-) stool specimens. Enteric parasites were common in these populations with 66% (251/380) of the study population harboring more than one parasite. In addition to the 13% (51/380) of patients determined to have E. histolytica by EIA, eighty-six patients (22.6%) had Blastocystis hominis, 54 (14.2%) Entamoeba coli, 44 (11.5%) Giardia lamblia, 16 (4.2%) Chilomastix mesnili, 15 (3.9%) Iodamoeba bütschlii, 12 (3.1%) Hymenolepis nana, 9 (2.3%) Endolimax nana, 9 (2.3%) Dientamoeba fragilis, and 8 (2.1%) had Ascaris lumbricoides. We concluded that E. histolytica infection was found in 13% of the patients presenting with diarrhea in Van and Sanliurfa Turkey.     

Application of a reverse line blot assay to the study of haemoparasites in cattle in Uganda

Recent advances in genomic technology have focused many veterinary researchers on the possibility of producing one multivalent recombinant vaccine against all the haemoparasites that infect cattle in the tropics. Before such a vaccine is developed it is essential to define target cattle populations as well as the range of anti-pathogen vaccines required in order to control disease. To further this objective, we have evaluated a reverse line blot (RLB) assay, which simultaneously detects the principal tick transmitted protozoan and rickettsial cattle pathogens, in different epidemiological scenarios in Uganda. A critical question is the sensitivity, particularly in relation to detecting carrier animals. As Theileria parva is considered to be the most important pathogen in the region, we assessed the sensitivity of the RLB assay for T. parva and showed that 1-2 x 10(3) parasites per ml of blood could be detected-a level comparable with previously developed PCR methods and well below conventional microscopic detection. We applied the RLB assay to evaluate the differences in pathogen profiles between crossbred and indigenous cattle and show that there were different profiles, with a low prevalence of T. parva and Theileria taurotragi in the indigenous cattle compared to a high prevalence in the crossbred cattle. In contrast, we show higher prevalences of Theileria mutans and Theileria velifera in the indigenous compared to the crossbred cattle. Interestingly Anaplasma marginale, Babesia bovis and Babesia bigemina were of low prevalence but a high prevalence of Ehrlichia bovis was seen, raising the question of whether this rickettsial species could be pathogenic in cattle. Analysis of animals with clinical symptoms of East Coast Fever showed that, while T. parva is a major cause of these symptoms, T. mutans and possibly T. taurotragi and T. velifera, may also cause clinical disease. Overall, the results presented here highlight the complexity of tick-borne pathogen infections in cattle in Uganda.     

Immunoinformatic analysis of the SARS-CoV-2 envelope protein as a strategy to assess cross-protection against COVID-19

Envelope protein of coronaviruses is a structural protein existing in both monomeric and homo-pentameric form. It has been related to a multitude of roles including virus infection, replication, dissemination and immune response stimulation. In the present study, we employed an immunoinformatic approach to investigate the major immunogenic domains of the SARS-CoV-2 envelope protein and map them among the homologue proteins of coronaviruses with tropism for animal species that are closely inter-related with the human beings population all over the world. Also, when not available, we predicted the envelope protein structural folding and mapped SARS-CoV-2 epitopes. Envelope sequences alignment provides evidence of high sequence homology for some of the investigated virus specimens; while the structural mapping of epitopes resulted in the interesting maintenance of the structural folding and epitope sequence localization also in the envelope proteins scoring a lower alignment score. In line with the One-Health approach, our evidences provide a molecular structural rationale for a potential role of taxonomically related coronaviruses in conferring protection from SARS-CoV-2 infection and identifying potential candidates for the development of diagnostic tools and prophylactic-oriented strategies.     

HBV套式PCR技术的建立及HBcAb血清的检测

本文实验设计了套式ＰＣＲ引物进行ＨＢＶＤＮＡ诊断。外引物限定ＨＢＶＣ基因的一个６１３ｂｐ片段,内引物限定其内－５０７ｂｐ的片段,扩增后产物被限制性内切酶图谱证明。该技术的特异性强,重复性好,灵敏性达到１－１０ｆｇ,对ＨＢＶ血清可做出明确诊断。应用这项技术,对４２例ＨＢｃＡｂ血清进行了检测,实验表明仅ＨＢｃＡｂ阳性血清同带ＨＢｓＡｇ的ＨＢｃＡｂ阳性血清一样,体内持续进行着大量ＨＢＶＤＡＮ复制。     

肾嗜酸性细胞瘤的诊治体会（附11例报告）

目的：探讨肾嗜酸细胞瘤的诊断和治疗。方法：回顾分析我院2003．2009年间收治11例肾嗜酸细胞瘤的临床资料,结合文献对肾嗜酸细胞瘤的诊断及治疗进行复习讨论。结果：本组11例患者中,年龄为26—75岁,男性7例,女性4例。合并透明细胞癌者1例,术前误诊为肾上腺肿瘤者1例。7例行根治性肾切除术者,4例行肾部分切除术。术后随访11个月-7年未见肿瘤转移或复发。结论：肾嗜酸细胞瘤倾向于良性肾实质性肿瘤,临床表现无特异性,确诊需临床表现、影像学检查与病理学检查相结合。治疗首选保肾手术,但应注意并发恶性肿瘤的可能,加强随访。     

应用电视胸腔镜诊治病因不明胸腔积液的疗效观察

目的:探讨电视胸腔镜(video-assisted thoracoscopic surgery VATS)在诊治病因不明胸腔积液中的应用价值.方法:回顾分析2005年4月～2011年4月196例病因不明胸腔积液经电视胸腔镜手术的临床资料.均应用电视胸腔镜进行探查,根据病变情况选择切口部位.排净胸腔积液后,分离粘连,进行胸膜活检后恶性患者行胸膜固定术.结果:196例均明确诊断:140例恶性胸腔积液,36例结核胸腔积液,20例炎性胸腔积液.胸腔镜手术178例,胸腔镜辅助胸壁小切口手术18例.手术时间30～75min,平均54 min.出血量10～120mL,平均53 mL.10例出现术后肺漏气,胸腔引流量＜50 mL/24h拔除胸腔引流管,胸管留置时间4～19天,平均9.4天.191例成功控制胸腔积液,全组无院内死亡.22例接受化疗的恶性胸腔积液患者,随访14～34个月,平均23个月,复查胸片显示无胸腔积液、积气.结论:电视胸腔镜安全、有效、微创,便于操作,可作为诊治病因不明胸腔积液的主要方法.     

肺栓塞的诊治和预防策略

急性肺栓塞(PE)是一种心血管疾病突发事件,具有较高的发病率和死亡率。一旦发生PE,快速、有效的诊治是挽救PE患者生命的关键,但也是呼吸内科医生一直面临的挑战。尽管PE的诊断手段和评估方法已经取得了很大地进步,但由于PE患者临床表现的非特异性和诊断方法的多样、复杂性,如何采取及时、有效的诊治策略仍是呼吸内科医生面临的重要难题。与此同时,由于PE诊断困难,治疗风险大,也使其临床预防势在必行。鉴于此,本文综述了当前欧洲心脏病学会(ESC)等国际心血管研究机构发布的PE诊治指导方针和研究进展,为读者进一步认识和掌握PE快速、有效的诊治和预防策略提供参考。