Update on the distribution and phylogenetics of Biomphalaria (Gastropoda: Planorbidae) populations in Guangdong Province,China

In 1973 planorbid snails then identified as Biomphalaria straminea were discovered in Hong Kong, China. It was assumed that these snails had been introduced to Hong Kong via the import of tropical fish by air from South America. In 2012 Biomphalaria were found for the first time in Guangdong Province, China. In view of the renewed interest in these invasive snails, a morphological and DNA-sequence based phylogenetic study was undertaken for seven populations of Biomphalaria snails collected in Guangdong. Morphologically and phylogenetically, five of the populations clustered more closely with Biomphalaria kuhniana than with B. straminea. Levels of genetic diversity among the populations were about half those of autochthonous populations in Brazil, the phylogenetic relationships did not correlate with a radiation from any one international port in China, and different lineages appeared associated with different ports. Consequently in explaining the current distribution of the snails, multiple colonization events, each establishing a new local snail population near to maritime international container ports, were considered more likely than the spread of snails from Hong Kong to China. The displacement of B. straminea by B. kuhniana in Guangdong is considered as an explanation for the habitat changes observed among the snails between Hong Kong in the 1980s and the present. The conclusions of the study are that any risk of Schistosoma mansoni transmission in China is more likely to come from parasite importation in the intramolluscan stage, than from transmission by migrant workers from South America or Africa. In addition, although likely to be rare, sporadic outbreaks of imported schistosomiasis (caused by invading infected snails) could be a threat to public health in the vicinity of International container ports (not only in Guangdong Province). Further work is called for to investigate further the presence of B. kuhniana and its potential interactions with B. straminea (the former is thought to be incompatible with S. mansoni), and the responses of Chinese Biomphalaria to potential competitors such as Thiaridae. The current expansion of container ports in Brazil and Venezuela, and the increase in trade with China, is likely to accentuate any current risk of imported schistosomiasis, and surveillance around ports in China, together with further research, are necessary.     

Performance of existing diagnosis/classification criteria for Behcet's disease in Iranian patients: analysis of 5666 patients and 2406 controls

Aim: To analyse the performance of existing diagnosis/classification criteria for Behcet's disease (BD) in Iranian patients. There are 13 sets: Curth (1946), Hewitt (1969), Mason and Barnes (1969), Hewitt revised (1971), Japan (1972), Hubault and Hamza (1974), O'Duffy (1974), Cheng and Zhang (1980), Dilsen (1986), Japan revised (1988), International (1990), Iran (1993), Classification Tree (1993), and Dilsen revised criteria (2000). Methods: All patients from the Behcet's Disease Registry (5666) and control patients (2406) entered the study. Sensitivity, specificity and accuracy were calculated. Results: The most sensitive was Curth criteria with (99.7%), followed by Classification Tree (97.3%), Zhang (93.5%), Iran (91.4%), Japan revised (86.4%), Japan (85.3%), Dilsen (83.7%), Hubault and Hamza (81.6%), Dilsen revised (81.2%), International criteria (79.8%), Hewitt (73.8%), O'Duffy (70.7%), and Masson and Barnes (65.7%). The most specific was Masson and Barnes (99.6%), followed by the International criteria (98.3%), Dilsen revised (98.2%), O'Duffy (97.6%), Japan (97.1%), Japan revised (97%), Classification Tree (96.7%), Hewitt (95.8%), Iran (95.8%), Zhang (92.4%), Dilsen (91.4%), Hubault (90.8%), and Curth (78.6%). The most accurate criteria was Classification Tree (97.1%), followed by Curth (93.4%), Zhang (93.1%), Iran (92.7%), Japan revised (89.6%), Japan (88.8%), Dilsen revised (86.2%), Dilsen (86%), International criteria (85.3%), Hubault (84.3%), Hewitt (80.4%), O'Duffy (78.8%), and Mason and Barnes (75.8%). Discussion: Among the existing criteria, the best to classify Iranian patients is the Classification Tree. The second most accurate is Curth criteria. The difference is statistically significant. Further, Curth criteria is not optimized, having very high sensitivity and low specificity.     

Analyzing the human liver vascular architecture by combining vascular corrosion casting and micro‐CT scanning: a feasibility study

Although a full understanding of the hepatic circulation is one of the keys to successfully perform liver surgery and to elucidate liver pathology, relatively little is known about the functional organization of the liver vasculature. Therefore, we materialized and visualized the human hepatic vasculature at different scales, and performed a morphological analysis by combining vascular corrosion casting with novel micro‐computer tomography (CT) and image analysis techniques. A human liver vascular corrosion cast was obtained by simultaneous resin injection in the hepatic artery (HA) and portal vein (PV). A high resolution (110 μm) micro‐CT scan of the total cast allowed gathering detailed macrovascular data. Subsequently, a mesocirculation sample (starting at generation 5; 88 × 68 × 80 mm³) and a microcirculation sample (terminal vessels including sinusoids; 2.0 × 1.5 × 1.7 mm³) were dissected and imaged at a 71‐μm and 2.6‐μm resolution, respectively. Segmentations and 3D reconstructions allowed quantifying the macro‐ and mesoscale branching topology, and geometrical features of HA, PV and hepatic venous trees up to 13 generations (radii ranging from 13.2 mm to 80 μm; lengths from 74.4 mm to 0.74 mm), as well as microvascular characteristics (mean sinusoidal radius of 6.63 μm). Combining corrosion casting and micro‐CT imaging allows quantifying the branching topology and geometrical features of hepatic trees using a multiscale approach from the macro‐ down to the microcirculation. This may lead to novel insights into liver circulation, such as internal blood flow distributions and anatomical consequences of pathologies (e.g. cirrhosis).     

临床决策树法与积分模型法对结核性胸膜炎的诊断效能比较

目的 探讨临床决策树法与积分模型法对结核性胸膜炎的诊断效能。方法 采用前瞻性随机对照研究方法,以2019年1月1日—2019年6月30日武汉市肺科医院收治的胸腔积液患者为研究对象。符合入组标准的胸腔积液患者随机入组临床决策树法组和积分模型法组,分别采用两种综合诊断模型进行诊断,对比两组方法的诊断效能。结果 临床决策树组共纳入127例患者,其中男性90例,女性37例,年龄18~88岁,平均（49.33±19.63）岁,最后诊断结核性胸膜炎108例,非结核性胸膜炎19例;积分模型组共纳入120例患者,其中男性89例,女性31例,年龄13~84岁,平均（46.41±20.01）岁,最后诊断结核性胸膜炎94例,非结核性胸膜炎26例。临床决策树法诊断结核性胸膜炎的敏感度57.4%,特异度78.9%,阳性预测值93.9%,阴性预测值24.6%,诊断准确率60.6%;积分模型法诊断结核性胸膜炎的敏感度75.5%,特异度96.2%,阳性预测值98.6%,阴性预测值52.1%,诊断准确率80.0%。结论 积分模型法诊断结核性胸膜炎敏感度、特异度及诊断准确率均高于临床决策树法,方法简单,可推广应用于结核性胸膜炎的临床诊断。     

饶河地区野生动物携带病毒的基因分型及序列特征分析

目的 确定当前饶河地区宿主动物所携带病原体的基因型别,分析其变异情况,对该地区自然宿主动物的感染情况进行监测。方法 使用TRIZOL法提取待测样本RNA,经RT-PCR扩增后对PCR产物进行核苷酸序列测定。应用DNAStar软件包对核苷酸序列进行同源性比较,构建系统进化树和氨基酸序列的比对。结果 在饶河地区,除褐家鼠(Rattus norvegicus)以外,松鼠(Sciurus vulgaris)也携带SEOV。本次从3只褐家鼠和1只松鼠体内分离出汉城型汉坦病毒(Seoul virus, SEOV),4株SEOV的遗传距离范围为0.00~0.01,与黑龙江地区常见SEOV病毒株亲缘关系较近。结论 黑龙江地区的气候和自然地理条件非常适合携带汉坦病毒(HV)宿主动物的生存和繁殖,但是随着人们生活条件的改善,禁止伐木狩猎,家鼠和野鼠与人类交集的逐渐减小,肾综合征出血热(HFRS)在黑龙江省暴发的概率也越来越小。     

中国广西登革3型病毒分离株基因组序列特征分析

目的对我国广西登革3型病毒分离株桂登-1株(GD-1株)和桂登-11株(GD-11株)进行全基因组序列测定和分析,为了解其地理来源提供依据。方法根据GenBank提交的登革3型病毒基因序列设计9对引物,RT-PCR方法分段扩增GD-1和GD-11株基因序列,测序后进行拼接,得到其全基因组序列。结果两株病毒全长均为10 707nt,与国际参考株H87株核苷酸同源性为96.0%,氨基酸同源性为98.8%。GD-1株和GD-11株间仅有4个氨基酸差异,二者与H87株分别存在39和41个氨基酸差异。对3’UTR二级结构进行预测,二者与H87株存在较大差异。根据E蛋白基因序列对两株病毒进行进化分析,GD-1和GD-11均属于亚型Ⅱ,与分离自泰国的两毒株进化关系较近。结论 GD-1和GD-11均属于登革3型病毒亚型Ⅱ,二者可能是源自泰国的病原。     

腺病毒7型河南分离株全基因序列测定及重组分析

目的了解腺病毒7型河南分离株（hAdV35/Henan/2010）全基因特征及与其他腺病毒之间的进化重组关系。方法设计39对全长引物,采用RT-PCR方法扩增河南分离株腺病毒全序列,用DNASTAR中的SeqMan拼接全序,运用BioEdit进行序列剪齐,运用Mega4.0分析基因组编码蛋白hexon、fiber、E4和penton区域氨基酸与核苷酸的同源性,并与其他腺病毒序列绘制进化树,运用Simplot软件进行序列重组分析。结果 hAdV35/Henan/2010基因组全长35 234bp,与其他腺病毒相比,基因组氨基酸和核苷酸同源性为68.0%-99.8%和46.5%-99.5%。不同编码区hexon、fiber、E4和penton的核苷酸同源性分别为72.4%-95.4%、74.1%-97.0%、55.7%-92.7%和69.9%-99.3%。进化树分析显示河南分离株与腺病毒7型疫苗株同属一支,与腺病毒3型进化分支最近,Bootsacn分析显示与B亚属腺病毒在多个区域发生重组,尤其与腺病毒3在hexon区域高度重组。结论 hAdV35/Henan/2010与B族腺病毒亲缘关系较近,与hAdV3在hexon区域存在重组。