Respiratory syncytial virus infections during an epidemic period in Salvador, Brazil. Viral antigenic group analysis and description of clinical and epidemiological aspects

Acute respiratory infections (ARI) caused by respiratory syncytial virus (RSV) were studied in 482 children from Salvador, BA, Brazil, over a period of 12 months. The epidemic period of RSV infections in Salvador occurred from February (summer) to August (winter), with peaks in May, June, and July. The grouping characteristics of 84 RSV present in nasopharyngeal secretions of children seen at a reference university hospital were analyzed. RSV represented 17.4% of all cases and 54.5% of the positive samples. Sixty-four RSV strains were assigned to group A and 14 to group B. Both groups circulated in the five months of the epidemic period studied. Infections by both groups of RSV were more frequent in children up to one year of age. The incidence of RSV ARI was slightly more frequent in males, although group B had more infected females.     

Whole genome sequencing and evolutionary analysis of human respiratory syncytial virus A and B from Milwaukee, WI 1998-2010

Background

Respiratory Syncytial Virus (RSV) is the leading cause of lower respiratory-tract infections in infants and young children worldwide. Despite this, only six complete genome sequences of original strains have been previously published, the most recent of which dates back 35 and 26 years for RSV group A and group B respectively.

Methodology/Principal Findings

We present a semi-automated sequencing method allowing for the sequencing of four RSV whole genomes simultaneously. We were able to sequence the complete coding sequences of 13 RSV A and 4 RSV B strains from Milwaukee collected from 1998–2010. Another 12 RSV A and 5 RSV B strains sequenced in this study cover the majority of the genome. All RSV A and RSV B sequences were analyzed by neighbor-joining, maximum parsimony and Bayesian phylogeny methods. Genetic diversity was high among RSV A viruses in Milwaukee including the circulation of multiple genotypes (GA1, GA2, GA5, GA7) with GA2 persisting throughout the 13 years of the study. However, RSV B genomes showed little variation with all belonging to the BA genotype. For RSV A, the same evolutionary patterns and clades were seen consistently across the whole genome including all intergenic, coding, and non-coding regions sequences.

Conclusions/Significance

The sequencing strategy presented in this work allows for RSV A and B genomes to be sequenced simultaneously in two working days and with a low cost. We have significantly increased the amount of genomic data that is available for both RSV A and B, providing the basic molecular characteristics of RSV strains circulating in Milwaukee over the last 13 years. This information can be used for comparative analysis with strains circulating in other communities around the world which should also help with the development of new strategies for control of RSV, specifically vaccine development and improvement of RSV diagnostics.     

The effects of resveratrol on cyclooxygenase-1 and -2, nuclear factor kappa beta, matrix metalloproteinase-9, and sirtuin 1 mRNA expression in hearts of streptozotocin-induced diabetic rats

Resveratrol (RSV) has a beneficial role in the prevention of diabetes and alleviates some diabetic complications, such as cardiomyopathy. We investigated cyclooxygenase-1 (COX-1), COX-2, nuclear factor κB (NF-κB), matrix metalloproteinase-9 (MMP-9), and sirtuin 1 (SIRT1) mRNA expression levels in heart tissue after RSV treatment in streptozotocin (STZ)-induced diabetic rats. After induction of chronic diabetes with STZ, 10 mg RSV/kg per day was administered to DM and DM+RSV groups for four weeks. At the end of the experiment, all rats were sacrificed and heart tissues were stored at -80°C; mRNA expression levels of COX-1, COX-2, NF-κB, MMP-9, and SIRT1 genes were analyzed with quantitative real-time PCR. We did not find any significant effect of RSV on MMP-9, COX-1, COX-2, or NF-κB mRNA levels among the groups. However, SIRT1 mRNA levels decreased in the DM group compared to controls and increased in the DM+RSV group when compared to the DM group. SIRT1 is activated by RSV treatment in diabetic heart tissue. Activation of SIRT1 by RSV may lead to a new therapeutic approach for diabetic heart tissue. We conclude that RSV treatment can alleviate heart dysfunction by inhibiton of inflammatory gene expression such as SIRT1.     

婴幼儿呼吸道合胞病毒感染严重程度与基因分型及血清炎症因子水平的相关性

目的 探讨婴幼儿呼吸道合胞病毒(respiratory syncytial virus,RSV)感染严重程度与病毒基因分型及血清IL10、IL17、IL27水平的相关性。 方法 选取2017年3月1日至2018年3月1日我院收治的77例呼吸道合胞病毒感染患儿作为研究对象,对患儿鼻咽部位的分泌物进行取样,对呼吸道合胞病毒亚型和基因型进行检测,按照病情的严重程度,将患者分为轻度组、中度组和重度组。对各组患儿病情程度,RSV亚型分布及血清IL10、IL17、IL27水平进行比较。 结果 轻度组患儿病情评分为(1.22±0.11)分,中度组为(4.89±0.98)分,重度组为(7.08±0.97)分。77份RSV阳性标本共检出A亚型48例,B亚型29例,其中轻度组、中度组及重度组患者中的A亚型感染人数比例分别为52.17%,60.00%,78.95%。A亚型病毒中NA1型为优势基因型。重度组患儿中NA1型的比例显著高于中度组和轻度组。B亚型病毒中BA9为优势基因型。轻度组患儿BA9型比例显著高于中度组和重度组。轻度组患儿血清IL10、IL17、IL27水平最低,重度组IL10、IL17、IL27的水平最高(均P结论 不同病情程度呼吸道合胞病毒感染患儿其病毒基因型分布及血清炎症因子的水平存在显著差异,病毒基因型与疾病的严重程度具有相关性。病毒基因型及血清炎症因子的水平可以作为判断此类患儿病程的标志物。     

RAPD and mitochondrial DNA analysis of the soybean stalk weevil, Sternechus subsignatus (Coleoptera: Curculionidae)

Sternechus subsignatus Boheman (Curculionidae: Sternechini) is one of the primary Curculionidae species that reduces soybean yield in Brazil. Initially, outbreaks were reported in southern Brazil in 1973; but, more recent, outbreaks were reported in Bahia (summer 1997-1998) and Maranh?o (summer 2003-2004), two states in northeastern Brazil. A putative related species, S. pinguis (Fabricius), was first detected in Salta Province, Argentina. The objective of this study was to evaluate intraspecific molecular polymorphisms of geographically distinct Sternechus populations. Randomly amplified polymorphic DNA (RAPD) profiles and partial mitochondrial cytochrome B (CytB) gene sequences were used to determine whether individual soybean stalk weevils were one of two different species and to infer pest invasion pattern. Putative S. pinguis and S. subsignatus populations were collected in San Agustin (Cruz Alta, Tucumán Province, Argentina) and different sampling sites in the Brazilian states of Paraná, Bahia and Maranh?o. Polymorphic bands were obtained by RAPD and analyzed by Dice coefficients. Populations from southern Brazil were more closely related genetically to an Argentinean group than the populations sampled in northeastern Brazil. The Londrina Co., Brazil population displayed the highest intra-population genetic similarity. Most of the soybean stalk weevils collected from San Agustin, Tucumán, Argentina were divergent from those collected in Brazil. Sequencing and parsimony analysis of CytB did not differentiate specimens collected in Argentina and Brazil. Thus, our data show that soybean stalk weevil outbreaks and population increases in northeastern Brazil involved local genotypes.     

西藏地区儿童急性呼吸道感染中呼吸道合胞病毒的初步研究

本研究为了解西藏地区儿童急性呼吸道感染中呼吸道合胞病毒(Respiratory syncytial virus,RSV)及基因型别。首先采用直接免疫荧光法检测2011年4～7月西藏自治区人民医院儿科病房因急性呼吸道感染住院患儿的鼻咽分泌物标本中7种常见的呼吸道病毒及人类偏肺病毒(Human metapneumovirus,hMPV)的抗原。然后对RSV抗原阳性的标本分别提取RNA,用逆转录-巢式聚合酶链反应法(Nest-PCR)确定RSV型别,同时用实时荧光PCR(Real-Time PCR)方法进行验证。再通过对G蛋白基因PCR扩增产物序列测定确定RSV的基因型。通过与GenBank中不同地区RSV分离株的G蛋白基因序列比对,了解西藏地区RSV G蛋白的结构特点及变异情况。结果表明,从167例标本中检测出呼吸道病毒抗原阳性的为65例,总阳性率为38.9%(65/167),其中RSV 45例,占阳性标本的69.2%(45/65),对其中42例RSV阳性标本进行了PCR分型,其中40例为A亚型,2例为B亚型。对7株A亚型RSV G蛋白基因PCR产物测序结果显示,全部为GA2基因型。西藏RSV与RSV原型株A2株核苷酸的同源性为90.7%～91.8%,氨基酸的同源性只有86.5%～87.2%。氨基酸的变异主要集中在胞外区一个高度保守序列的两端。7株西藏A亚型RSV G蛋白的核苷酸序列与GenBank中不同的RSV分离株相比同源性为90.7%～91.8%。西藏地区2011年春季小儿急性呼吸道感染的病毒病原主要为呼吸道合胞病毒,A亚型是2011年西藏地区的流行优势型别,其G蛋白胞外区基因具有较高的变异性。     

Clonal Variation in the Sprouting Pattern of the Tubers in Eleocharis kuroguwai, a Cyperaceous Weed, with Special Reference to its Perennation Strategy

Abstract Clonal variation in the sprouting pattern of tubers in Eleocharis kuroguwai Ohwi was studied, using 39 clones collected within a longitudinally narrow belt from Wakasa Bay to the Kii Peninsula of Japan and one of "Ohkuroguwai", a cultivated form.
The sprouting pattern of tubers and the relationship between sprouting time and other tuber characteristics varied noticeably among clones. Based on the polygonal graphs of × (mean), (standard deviation), g₁ (skewness) and á (kurtosis) of the sprouting time, the sprouting pattern of 40 clones could be divided into the following three groups. Group A: and α were small, but g₁ and a' were generally great; almost all tubers sprouted early and simultaneously. Group B: and α were greater, but g₁ and a' were smaller than Group A; the majority of tubers sprouted quickly, but the rest of the tubers sprouted gradually. Group C: and α were very large, g₁ was small, but a' showed a comparatively large negative value; all tubers sprouted gradually over a long period.
Groups A and B were represented by the irrigation pond group from the Banshu Plain and by the Ohshima Island group in the paddy fields of the southern extremity of the Kii Peninsula. Clones from the paddy field group and from the plain group, both referable to typical rstrategists, exhibited various sprouting patterns of tubers.     

Distribution of ABO and rhesus blood groups in Abraka, Delta State, Nigeria.

Blood group systems are determined early in intrauterine life, specific to the individual and therefore significant in management and identification. Seven hundred and ninety five volunteer students of the Abraka campus of Delta State University were analyzed in this 4-year retrospective study. Amongst ABO system, blood group O was most common followed by A, B and AB respectively. Rhesus positive was more common than Rhesus negative in the rhesus system. Gender had no significant effect on both blood group systems studied. In the combined ABO and Rhesus blood groups, O positive was most common followed by A positive, B positive, AB positive O negative and A negative respectively. This study documents ABO and Rhesus blood group distribution patterns amongst south southern Nigerians. Findings will be useful in maintaining a register of possible donors, for effective management of medical emergencies.     

Electrophoretic analysis of ITS from Piscirickettsia salmonis Chilean isolates

Piscirickettsia salmonis is the most important pathogen in salmonid mariculture in Chile. Since it was reported numerous piscirickettsiosis outbreaks have occurred differing in virulence and mortality. Genetic variability of P. salmonis isolates has been suggested as one factor to explain this. However until now isolates obtained from outbreaks have not been analyzed. Knowledge of genetic variability of P. salmonis is very limited and also a useful screening method for genetic variations in isolates without sequencing is not available. Here we report an electrophoretic analysis of internal transcribed spacer region (ITS) of eleven P. salmonis isolates obtained from different salmon species and places in southern Chile. When PCR products were submitted to polyacrylamide gel electrophoresis (PAGE) a characteristic electrophoretic pattern was observed, distinguishable from ITS of other bacteria, including fish pathogens. Even though this pattern is conserved in all isolates, a difference in ITS electrophoretic mobility was observed, determining clearly two groups: ITS with higher or with lower electrophoretic mobility, including LF-89 and EM-90 isolates, respectively. A higher ITS sequence homology inside each group was shown by heteroduplex mobility assay (HMA). Our results show that genetic variability between Chilean P. salmonis isolates allows the differentiation of two groups with similar behavior observed previously when six P. salmonis isolates from three geographic origins were analyzed by 16S, 23S and ITS sequencing. PAGE analysis of ITS and HMA could be a basis to develop an assay for screening genetic variability between P. salmonis isolates.     

Human botulism in Canada (1919-1973)

Since 1919, in Canada, 62 authenticated outbreaks of human botulism have affected 181 persons, with 83 deaths, a fatality rate of 46%. Among these, 41 outbreaks were bacteriologically determined (31 in one laboratory) as six type A, four type B, one both A and B, and 30 type E. About two thirds of the total outbreaks, cases and deaths involved Eskimos and Pacific coast Indians consuming raw marine mammal products and salmon eggs, respectively. Other parts of Canada recorded seven occurrences due to miscellaneous vehicles, three being type B. Since January 1961 there have been 38 outbreaks, involving 94 cases with 33 deaths. These include 18 outbreaks among Eskimos, affecting 51 persons (of whom 24 died) in Labrador, southern Baffin Island, northern Quebec, and the Mackenzie area. Also, putrid salmon eggs caused 15 outbreaks among Pacific coast Indians, totalling 35 cases, of whom only six died, the low fatality rate reflecting the introduction of type E botulinus antitoxin during 1961.     

武汉地区1988—1992年呼吸道合胞病毒流行株的抗原性分析

利用呼吸道合胞病毒的单克隆抗体,通过间接免疫荧光法和免疫转印法对本室分离到的武汉地区１９８８－１９９２年的５６份ＲＳＶ毒株进行了分型,可将其分为Ａ、Ｂ两型和Ｂ１、Ｂ２亚型,流行病学分析显示：本地区ＲＳＶ的主要流行株,四年中有三年为Ｂ型株。不同于欧美等地;Ａ、Ｂ两型的分布还具有灶化分布的特点;两型在性别、发病年龄之间无显著性差异。     

呼吸道合胞病毒感染促进豚鼠产生气道高反应性及其机制研究

目的：通过检测气道反应性和M2受体功能,研究呼吸道合胞病毒（RSV）感染与哮喘发病的关系及机制。方法：34只豚鼠随机分为4组：Hep-2滴鼻＋生理盐水雾化（Hep-2／NS,A）组,RSV滴鼻＋生理盐水雾化（RSV／NS,B）组,Hep-2滴鼻＋鸡卵蛋白（OVA）雾化（Hep-2／OVA,C）组和RSV滴鼻＋OVA雾化（RSV／OVA,D）组,其中A和B纽各9只,C和D组各8只,以A组为对照组。21d通过电刺激迷走神经检测各组气道反应性和M2受体功能,行嗜酸性粒细胞计数以及病理学观察。结果：B组气道内压力（mmH2O）与A组无明显差异（P〉0．05）,给予匹罗卡品,IP下降幅度高于A组,但差别无显著性（P〉0．05）。C组IP明显高于A且（P〈0．05）,且给予匹罗卡品,IP下降幅度明显低于A组,差别有显著性（P〈0．05）。D组IP明显高于C组（P〈0．05）,给予匹罗卡品后IP下降幅度明显低于C组（P〈0．05）。结论：RSV感染可促进过敏原引起的M2R功能障碍,从而促进AHR发生。     

肠道病毒B组山东地方株的基因型分布

为明确源自急性弛缓性麻痹(AFP)病例的HEV-B组病毒山东地方株的基因型分布,探讨其优势基因型的变迁与疾病暴发之间的关系,本研究对山东省1994年~2008年AFP监测系统分离到的HEV-B组病毒进行了VP1区核酸扩增和序列测定。序列测定结果显示HEV-B山东地方株共包括29种基因型,其中CVA 1种(CVA9),CVB 5种(CVB1~5),ECHO 20种以及新型肠道病毒EV73、75、97。其中ECHO11、CVB3、ECHO6、ECHO14、ECHO25是AFP监测系统中最常分离到的B组病毒。同源性比较显示,相同血清型HEV-B山东地方株型内核苷酸同源性最小75.4%,最大99.6%,与原型株核苷酸同源性最小73.8%,最大85.2%,但氨基酸变异不大。研究表明,不同基因型病毒具有不同的时间循环模式,相同基因型毒株内部根据其遗传距离的远近又可划分为不同的基因亚型,从而帮助确定HEV的传播途径和传播范围。     

Respiratory syncytial virus (RSV) F, G, M2 (22K), and N proteins each induce resistance to RSV challenge, but resistance induced by M2 and N proteins is relatively short-lived.

The ability of recombinant vaccinia viruses that separately encoded 9 of the 10 known respiratory syncytial virus (RSV) proteins to induce resistance to RSV challenge was studied in BALB/c mice. Resistance was examined at two intervals following vaccination to examine early (day 9) as well as late (day 28) immunity. BALB/c mice were inoculated simultaneously by the intranasal and intraperitoneal routes with a recombinant vaccinia virus encoding one of the following RSV proteins: F, G, N, P, SH, M, 1B, 1C, or M2 (22K). A parainfluenza virus type 3 HN protein recombinant (Vac-HN) served as a negative control. One half of the mice were challenged with RSV intranasally on day 9, and the remaining animals were challenged on day 28 postvaccination. Mice previously immunized by infection with RSV, Vac-F, or Vac-G were completely or almost completely resistant to RSV challenge on both days. In contrast, immunization with Vac-HN, -P, -SH, -M, -1B, or -1C did not induce detectable resistance to RSV challenge. Mice previously infected with Vac-M2 or Vac-N exhibited significant but not complete resistance on day 9. However, in both cases resistance had largely waned by day 28 and was detectable only in mice immunized with Vac-M2. These results demonstrate that F and G proteins expressed by recombinant vaccinia viruses are the most effective RSV protective antigens. This study also suggests that RSV vaccines need only contain the F and G glycoproteins, because the immunity conferred by the other proteins is less effective and appears to wane rapidly with time.     

The influence of seasonal temperatures on the natural regulation of the screw worm, Cochliomyia hominivorax, in the southern U.S.A.

The incidence of screwworm cases in Texas during the 1962-82 sterile-male eradication campaign is analysed in relation to seasonal temperatures and screwworm density. The analysis shows that screwworm outbreaks occur in response to favourable seasonal conditions, especially warm winters and cool summers. The outbreaks collapse following cold winters and hot summers. Screwworm density in autumn also influences rates of increase, possibly through a shortage of wounded hosts in the autumn-winter period. The analysis provides a simple predictive model which not only accounts for the fluctuations in case incidence seen in Texas during the eradication campaign, which others have attributed to strain problems and release methods, but also simulates the historical pattern of screwworm abundance in both Texas and Florida over the last 100 years. It is concluded that screwworm, being essentially a tropical species, might well have been eradicated from the southern U.S.A. by exceptionally unfavourable climate such as occurred in Florida in 1958 and in Texas in the late 1970s and early 1980s. Certainly, unfavourable climate must have been important to the success of the eradication campaigns.     

云南16个少数民族群体的线粒体DNA多态性研究

利用PCR—RFLP法对傣族、白族、蒙古族、彝族等10个少数民族的16个群体共654人进行了mtDNA编码区多态性分析,共检测到17种单倍群,其中4种为未能确认的单倍群。单倍群频率分布和主成分图共同显示,百越系的3个民族共6个群体有高频的B、F单倍群,聚集在图的下部,表现出鲜明的南方群体特征;蒙古族的2个群体有高频的A、D单倍群,聚在图的上部,具有典型的北方群体特征;氐羌系的5个民族共7个群体全部或绝大多数都兼有南北方高频单倍群,位于图的中间,提示他们同时具有南北方群体的一些母系遗传特征。同一民族不同群体间的单倍群频率分布存在差异,但差异不很大,一般小于不同族源民族间的差异,但不一定都小于同一族源民族间的差异。