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Sample records for etiologic viral strains

  1. Venezuelan Equine Encephalitis in Panama: Fatal Endemic Disease and Genetic Diversity of Etiologic Viral Strains

    PubMed Central

    Quiroz, Evelia; Aguilar, Patricia V.; Cisneros, Julio; Tesh, Robert B.; Weaver, Scott C.

    2009-01-01

    Venezuelan equine encephalitis (VEE) is a reemerging, mosquito-borne viral disease of the neotropics that is severely debilitating and sometimes fatal to humans. Periodic epidemics mediated by equine amplification have been recognized since the 1920s, but interepidemic disease is rarely recognized. We report here clinical findings and genetic characterization of 42 cases of endemic VEE detected in Panama from 1961–2004. Recent clusters of cases occurred in Darien (eastern Panama) and Panama provinces (central Panama) near rainforest and swamp habitats. Patients ranged from 10 months to 48 years of age, and the more severe cases with neurological complications, including one fatal infection, were observed in children. The VEE virus strains isolated from these cases all belonged to an enzootic, subtype ID lineage known to circulate among sylvatic vectors and rodent reservoir hosts in Panama and Peru. These findings underscore endemic VEE as an important but usually neglected arboviral disease of Latin America. PMID:19564908

  2. Viral etiology, clinical and laboratory features of adult hemophagocytic lymphohistiocytosis.

    PubMed

    Chen, Jinghong; Wang, Xuehua; He, Ping; Li, Yazhen; Si, Mengya; Fan, Zhichen; Chang, Xiaolan; Xie, Qindong; Jiao, Xiaoyang

    2016-03-01

    Secondary hemophagocytic lymphohistiocytosis (SHLH) is a potentially fatal hyperinflammatory syndrome with a heterogeneous etiology and has nonspecific clinical and laboratory findings. The diagnosis and treatment of adult SHLH is challenging because the etiology of the disease is difficult to identify, and the majority of reported cases are pediatric patients. The aim of this study was to describe the etiology, clinical characteristics, and outcomes of adult SHLH. Fifty-four adult patients who fulfilled the criteria of SHLH were enrolled in the study. Viral etiology, blood biomarkers, and clinical manifestations of SHLH were analyzed in these patients. Twenty-four SHLH patients had viraemia, whereas 30 SHLH patients were secondary to other diseases. Epstein-Barr virus (EBV) was the most common virus that associated SHLH among all viruses studied. Severe SHLH patients with EBV-viraemia presented significantly high levels of ferritin, lactate dehydrogenase, aspartate transaminase (AST), and alanine transaminase (ALT). Positively relationships existed between EBV DNA titers and levels of AST and ALT (P < 0.05). The prognosis of SHLH patients with EBV viraemia was worse than that of non-EBV SHLH and non-viral SHLH. Our data reveal that EBV is the major pathogen in virus-associated SHLH, and EBV load influence disease development in SHLH patients with EBV infection that prognosis is worse than other viruses associated SHLH. PMID:26287378

  3. Viral perturbations of host networks reflect disease etiology.

    PubMed

    Gulbahce, Natali; Yan, Han; Dricot, Amélie; Padi, Megha; Byrdsong, Danielle; Franchi, Rachel; Lee, Deok-Sun; Rozenblatt-Rosen, Orit; Mar, Jessica C; Calderwood, Michael A; Baldwin, Amy; Zhao, Bo; Santhanam, Balaji; Braun, Pascal; Simonis, Nicolas; Huh, Kyung-Won; Hellner, Karin; Grace, Miranda; Chen, Alyce; Rubio, Renee; Marto, Jarrod A; Christakis, Nicholas A; Kieff, Elliott; Roth, Frederick P; Roecklein-Canfield, Jennifer; Decaprio, James A; Cusick, Michael E; Quackenbush, John; Hill, David E; Münger, Karl; Vidal, Marc; Barabási, Albert-László

    2012-01-01

    Many human diseases, arising from mutations of disease susceptibility genes (genetic diseases), are also associated with viral infections (virally implicated diseases), either in a directly causal manner or by indirect associations. Here we examine whether viral perturbations of host interactome may underlie such virally implicated disease relationships. Using as models two different human viruses, Epstein-Barr virus (EBV) and human papillomavirus (HPV), we find that host targets of viral proteins reside in network proximity to products of disease susceptibility genes. Expression changes in virally implicated disease tissues and comorbidity patterns cluster significantly in the network vicinity of viral targets. The topological proximity found between cellular targets of viral proteins and disease genes was exploited to uncover a novel pathway linking HPV to Fanconi anemia. PMID:22761553

  4. Viral Perturbations of Host Networks Reflect Disease Etiology

    PubMed Central

    Dricot, Amélie; Padi, Megha; Byrdsong, Danielle; Franchi, Rachel; Lee, Deok-Sun; Rozenblatt-Rosen, Orit; Mar, Jessica C.; Calderwood, Michael A.; Baldwin, Amy; Zhao, Bo; Santhanam, Balaji; Braun, Pascal; Simonis, Nicolas; Huh, Kyung-Won; Hellner, Karin; Grace, Miranda; Chen, Alyce; Rubio, Renee; Marto, Jarrod A.; Christakis, Nicholas A.; Kieff, Elliott; Roth, Frederick P.; Roecklein-Canfield, Jennifer; DeCaprio, James A.; Cusick, Michael E.; Quackenbush, John; Hill, David E.; Münger, Karl; Vidal, Marc; Barabási, Albert-László

    2012-01-01

    Many human diseases, arising from mutations of disease susceptibility genes (genetic diseases), are also associated with viral infections (virally implicated diseases), either in a directly causal manner or by indirect associations. Here we examine whether viral perturbations of host interactome may underlie such virally implicated disease relationships. Using as models two different human viruses, Epstein-Barr virus (EBV) and human papillomavirus (HPV), we find that host targets of viral proteins reside in network proximity to products of disease susceptibility genes. Expression changes in virally implicated disease tissues and comorbidity patterns cluster significantly in the network vicinity of viral targets. The topological proximity found between cellular targets of viral proteins and disease genes was exploited to uncover a novel pathway linking HPV to Fanconi anemia. PMID:22761553

  5. Zika Fetal Neuropathogenesis: Etiology of a Viral Syndrome

    PubMed Central

    Klase, Zachary A.; Khakhina, Svetlana; Schneider, Adriano De Bernardi; Callahan, Michael V.; Glasspool-Malone, Jill

    2016-01-01

    The ongoing Zika virus epidemic in the Americas and the observed association with both fetal abnormalities (primary microcephaly) and adult autoimmune pathology (Guillain–Barré syndrome) has brought attention to this neglected pathogen. While initial case studies generated significant interest in the Zika virus outbreak, larger prospective epidemiology and basic virology studies examining the mechanisms of Zika viral infection and associated pathophysiology are only now starting to be published. In this review, we analyze Zika fetal neuropathogenesis from a comparative pathology perspective, using the historic metaphor of “TORCH” viral pathogenesis to provide context. By drawing parallels to other viral infections of the fetus, we identify common themes and mechanisms that may illuminate the observed pathology. The existing data on the susceptibility of various cells to both Zika and other flavivirus infections are summarized. Finally, we highlight relevant aspects of the known molecular mechanisms of flavivirus replication. PMID:27560129

  6. Zika Fetal Neuropathogenesis: Etiology of a Viral Syndrome.

    PubMed

    Klase, Zachary A; Khakhina, Svetlana; Schneider, Adriano De Bernardi; Callahan, Michael V; Glasspool-Malone, Jill; Malone, Robert

    2016-08-01

    The ongoing Zika virus epidemic in the Americas and the observed association with both fetal abnormalities (primary microcephaly) and adult autoimmune pathology (Guillain-Barré syndrome) has brought attention to this neglected pathogen. While initial case studies generated significant interest in the Zika virus outbreak, larger prospective epidemiology and basic virology studies examining the mechanisms of Zika viral infection and associated pathophysiology are only now starting to be published. In this review, we analyze Zika fetal neuropathogenesis from a comparative pathology perspective, using the historic metaphor of "TORCH" viral pathogenesis to provide context. By drawing parallels to other viral infections of the fetus, we identify common themes and mechanisms that may illuminate the observed pathology. The existing data on the susceptibility of various cells to both Zika and other flavivirus infections are summarized. Finally, we highlight relevant aspects of the known molecular mechanisms of flavivirus replication. PMID:27560129

  7. Viral carcinogenesis: revelation of molecular mechanisms and etiology of human disease

    NASA Technical Reports Server (NTRS)

    Butel, J. S.

    2000-01-01

    The RNA and DNA tumor viruses have made fundamental contributions to two major areas of cancer research. Viruses were vital, first, to the discovery and analysis of cellular growth control pathways and the synthesis of current concepts of cancer biology and, second, to the recognition of the etiology of some human cancers. Transforming retroviruses carry oncogenes derived from cellular genes that are involved in mitogenic signalling and growth control. DNA tumor viruses encode oncogenes of viral origin that are essential for viral replication and cell transformation; viral oncoproteins complex with cellular proteins to stimulate cell cycle progression and led to the discovery of tumor suppressors. Viral systems support the concept that cancer development occurs by the accumulation of multiple cooperating events. Viruses are now accepted as bona fide etiologic factors of human cancer; these include hepatitis B virus, Epstein-Barr virus, human papillomaviruses, human T-cell leukemia virus type I and hepatitis C virus, plus several candidate human cancer viruses. It is estimated that 15% of all human tumors worldwide are caused by viruses. The infectious nature of viruses distinguishes them from all other cancer-causing factors; tumor viruses establish long-term persistent infections in humans, with cancer an accidental side effect of viral replication strategies. Viruses are usually not complete carcinogens, and the known human cancer viruses display different roles in transformation. Many years may pass between initial infection and tumor appearance and most infected individuals do not develop cancer, although immunocompromised individuals are at elevated risk of viral-associated cancers. Variable factors that influence viral carcinogenesis are reviewed, including possible synergy between viruses and environmental cofactors. The difficulties in establishing an etiologic role for a virus in human cancer are discussed, as well as the different approaches that proved

  8. Etiology and Viral Genotype in Patients with End-Stage Liver Diseases admitted to a Hepatology Unit in Colombia

    PubMed Central

    Cortes-Mancera, Fabian; Loureiro, Carmen Luisa; Hoyos, Sergio; Restrepo, Juan-Carlos; Correa, Gonzalo; Jaramillo, Sergio; Norder, Helene; Pujol, Flor Helene; Navas, Maria-Cristina

    2011-01-01

    Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the principal risk factor associated to end-stage liver diseases in the world. A study was carried out on end-stage liver disease cases admitted to an important hepatology unit in Medellin, the second largest city in Colombia. From 131 patients recruited in this prospective study, 71% of cases were diagnosed as cirrhosis, 12.2% as HCC, and 16.8% as cirrhosis and HCC. Regarding the risk factors of these patients, alcohol consumption was the most frequent (37.4%), followed by viral etiology (17.6%). Blood and/or hepatic tissue samples from patients with serological markers for HCV or HBV infection were characterized; on the basis of the phylogenetic analysis of HCV 5′ UTR and HBV S gene, isolates belonged to HCV/1 and HBV/F3, respectively. These results confirm the presence of strains associated with poor clinical outcome, in patients with liver disease in Colombia; additionally, HBV basal core promoter double mutant was identified in HCC cases. Here we show the first study of cirrhosis and/or HCC in Colombian and HBV and HCV molecular characterization of these patients. Viral aetiology was not the main risk factor in this cohort but alcohol consumption. PMID:21941645

  9. Viral Etiology of Encephalitis in Children in Southern Vietnam: Results of a One-Year Prospective Descriptive Study

    PubMed Central

    Tan, Le Van; Qui, Phan Tu; Ha, Do Quang; Hue, Nguyen Bach; Bao, Lam Quoi; Cam, Bach Van; Khanh, Truong Huu; Hien, Tran Tinh; Vinh Chau, Nguyen Van; Tram, Tran Tan; Hien, Vo Minh; Nga, Tran Vu Thieu; Schultsz, Constance; Farrar, Jeremy; van Doorn, H. Rogier; de Jong, Menno D.

    2010-01-01

    Background Acute encephalitis is an important and severe disease in children in Vietnam. However, little is known about the etiology while such knowledge is essential for optimal prevention and treatment. To identify viral causes of encephalitis, in 2004 we conducted a one-year descriptive study at Children's Hospital Number One, a referral hospital for children in southern Vietnam including Ho Chi Minh City. Methodology/Principal Findings Children less than 16 years of age presenting with acute encephalitis of presumed viral etiology were enrolled. Diagnostic efforts included viral culture, serology and real time (RT)-PCRs. A confirmed or probable viral causative agent was established in 41% of 194 enrolled patients. The most commonly diagnosed causative agent was Japanese encephalitis virus (n = 50, 26%), followed by enteroviruses (n = 18, 9.3%), dengue virus (n = 9, 4.6%), herpes simplex virus (n = 1), cytomegalovirus (n = 1) and influenza A virus (n = 1). Fifty-seven (29%) children died acutely. Fatal outcome was independently associated with patient age and Glasgow Coma Scale (GCS) on admission. Conclusions/Significance Acute encephalitis in children in southern Vietnam is associated with high mortality. Although the etiology remains unknown in a majority of the patients, the result from the present study may be useful for future design of treatment and prevention strategies of the disease. The recognition of GCS and age as predictive factors may be helpful for clinicians in managing the patient. PMID:21049060

  10. Viral Etiology of Influenza-Like Illnesses in Antananarivo, Madagascar, July 2008 to June 2009

    PubMed Central

    Razanajatovo, Norosoa Harline; Richard, Vincent; Hoffmann, Jonathan; Reynes, Jean-Marc; Razafitrimo, Girard Marcellin; Randremanana, Rindra Vatosoa; Heraud, Jean-Michel

    2011-01-01

    Background In Madagascar, despite an influenza surveillance established since 1978, little is known about the etiology and prevalence of viruses other than influenza causing influenza-like illnesses (ILIs). Methodology/Principal Findings From July 2008 to June 2009, we collected respiratory specimens from patients who presented ILIs symptoms in public and private clinics in Antananarivo (the capital city of Madagascar). ILIs were defined as body temperature ≥38°C and cough and at least two of the following symptoms: sore throat, rhinorrhea, headache and muscular pain, for a maximum duration of 3 days. We screened these specimens using five multiplex real time Reverse Transcription and/or Polymerase Chain Reaction assays for detection of 14 respiratory viruses. We detected respiratory viruses in 235/313 (75.1%) samples. Overall influenza virus A (27.3%) was the most common virus followed by rhinovirus (24.8%), RSV (21.2%), adenovirus (6.1%), coronavirus OC43 (6.1%), influenza virus B (3.9%), parainfluenza virus-3 (2.9%), and parainfluenza virus-1 (2.3%). Co-infections occurred in 29.4% (69/235) of infected patients and rhinovirus was the most detected virus (27.5%). Children under 5 years were more likely to have one or more detectable virus associated with their ILI. In this age group, compared to those ≥5 years, the risk of detecting more than one virus was higher (OR = 1.9), as was the risk of detecting of RSV (OR = 10.1) and adenovirus (OR = 4.7). While rhinovirus and adenovirus infections occurred year round, RSV, influenza virus A and coronavirus OC43 had defined period of circulation. Conclusions In our study, we found that respiratory viruses play an important role in ILIs in the Malagasy community, particularly in children under 5 years old. These data provide a better understanding of the viral etiology of outpatients with ILI and describe for the first time importance of these viruses in different age group and their period of circulation

  11. Viral etiology and seasonality of influenza-like illness in Gabon, March 2010 to June 2011

    PubMed Central

    2014-01-01

    Background Surveillance of influenza-like illness (ILI) in Central Africa began only recently, and few data are therefore available on the circulation of influenza virus and other respiratory viruses. In Gabon, a Central African country, we established a surveillance network in four major towns in order to analyze cases of ILI among patients who visited health centers between March 2010 and June 2011, and to determine the viral etiology. Methods Nasal swabs were sent for analysis to the Centre International de Recherches Médicales de Franceville, where they were screened for 17 respiratory viruses in a multiplex real-time reverse transcription polymerase chain reaction for all pathogens according the following pairs: adenovirus/parainfluenza virus 4, respiratory syncytial virus/human metapneumovirus, parainfluenza virus 1/parainfluenza virus 2, pandemic influenza virus A/seasonal influenza virus A (H1N1, H3N2)/seasonal influenza virus B, human coronaviruses 229E/OC43, human coronaviruses NL63/HKU1, rhinovirus/human parechovirus, and enterovirus/parainfluenza virus 3. Results We analyzed a total of 1041 specimens, of which 639 (61%) were positive for at least one virus. Three-quarters of the patients were children under five years old. We therefore focused on this age group, in which 68.1% of patients were positive for at least one virus. The most common viruses were adenoviruses (17.5%), followed by parainfluenza viruses (PIVs) 1–4 (16.8%), enteroviruses (EV) (14.7%), respiratory syncytial virus (RSV) (13.5%), and influenza virus (11.9%). The prevalence of some viruses was subject to geographic and seasonal variations. One-third of positive samples contained more than one virus. Conclusions Like most studies in the world, the virus PIVs, EV, RSV, Influenza virus, HRV were predominant among children under five years old in Gabon. An exception is made for adenoviruses which have a high prevalence in our study. However adenoviruses can be detected in asymptomatic

  12. Viral etiology of acute respiratory diseases in Rio de Janeiro: first two years of a longitudinal study

    PubMed Central

    Sutmoller, F.; Nascimento, J. P.; Chaves, J. R. S.; Ferreira, V.; Pereira, M. S.

    1983-01-01

    A two-year study was undertaken to establish the incidence and possible viral etiology of acute respiratory diseases among the child population of a shanty town in Rio de Janeiro, Brazil. The results demonstrated that nearly half of all the illnesses seen were respiratory infections, 10% of them affecting the lower respiratory tract. Viruses were isolated from 20% of the throat swabs collected. Of the viruses identified, 47% were adenoviruses, 25% were enteroviruses, 9% were influenza A, 8% herpes simplex, 7% parainfluenza, 3% respiratory syncytial and 1% influenza B viruses. PMID:6606500

  13. Viral Etiology of Respiratory Tract Infections in Children at the Pediatric Hospital in Ouagadougou (Burkina Faso)

    PubMed Central

    Ouédraogo, Solange; Traoré, Blaise; Nene Bi, Zah Ange Brice; Yonli, Firmin Tiandama; Kima, Donatien; Bonané, Pierre; Congo, Lassané; Traoré, Rasmata Ouédraogo; Yé, Diarra; Marguet, Christophe; Plantier, Jean-Christophe; Vabret, Astrid; Gueudin, Marie

    2014-01-01

    Background Acute respiratory infections (ARIs) are a major cause of morbidity and mortality in children in Africa. The circulation of viruses classically implicated in ARIs is poorly known in Burkina Faso. The aim of this study was to identify the respiratory viruses present in children admitted to or consulting at the pediatric hospital in Ouagadougou. Methods From July 2010 to July 2011, we tested nasal aspirates of 209 children with upper or lower respiratory infection for main respiratory viruses (respiratory syncytial virus (RSV), metapneumovirus, adenovirus, parainfluenza viruses 1, 2 and 3, influenza A, B and C, rhinovirus/enterovirus), by immunofluorescence locally in Ouagadougou, and by PCR in France. Bacteria have also been investigated in 97 samples. Results 153 children (73.2%) carried at least one virus and 175 viruses were detected. Rhinoviruses/enteroviruses were most frequently detected (rhinovirus n = 88; enterovirus n = 38) and were found to circulate throughout the year. An epidemic of RSV infections (n = 25) was identified in September/October, followed by an epidemic of influenza virus (n = 13), mostly H1N1pdm09. This epidemic occurred during the period of the year in which nighttime temperatures and humidity were at their lowest. Other viruses tested were detected only sporadically. Twenty-two viral co-infections were observed. Bacteria were detected in 29/97 samples with 22 viral/bacterial co-infections. Conclusions This study, the first of its type in Burkina Faso, warrants further investigation to confirm the seasonality of RSV infection and to improve local diagnosis of influenza. The long-term objective is to optimize therapeutic management of infected children. PMID:25360527

  14. Viral etiology of mumps-like illnesses in suspected mumps cases reported in Catalonia, Spain.

    PubMed

    Barrabeig, Irene; Costa, Josep; Rovira, Ariadna; Marcos, M Angeles; Isanta, Ricard; López-Adalid, Rubén; Cervilla, Ana; Torner, Nuria; Domínguez, Angela

    2015-01-01

    We investigated the etiology of reported sporadic suspected mumps cases with a negative RT-PCR result for the mumps virus in the Barcelona-South region in 2007-2011. Samples from mumps virus-negative patients presenting unilateral or bilateral parotitis or other salivary gland swelling were tested for Epstein-Barr virus (EBV) by real-time PCR and for respiratory viruses by two multiplex-PCR-based assays to detect parainfluenza virus (PIV) 1-4, influenza virus (InV) A, B and C, respiratory syncytial virus (RSV), enterovirus, coronavirus 229E, coronavirus OC43, and rhinovirus. 101 samples were analyzed in persons aged 8 months to 50 years. Oral samples were collected on the first day of glandular swelling in 53 patients (52.5%), and on the first two days in 74 patients (73.3%). Viruses were detected in 52 (51.5%) of samples: one virus (25 EBV, 8 PIV3, 4 adenovirus, 4 PIV2, 1 PIV1, 1 InVA, and 1 enterovirus) was detected in 44 patients (84.6%), two viruses in 7 patients, and three viruses in one patient. In 58 patients (57.5%) whose sample was collected in the first 2 days after onset of parotitis and had received two doses of MMR vaccine and in 15 patients (14.8%) whose sample was collected on the first day, it is very likely that the cause was not the mumps virus. This would mean that 72.3% (73/101) of the reported sporadic suspected mumps cases were not mumps cases. The timing of oral-sample collection is crucial to correctly interpret the negative results for mumps virus RNA, especially when suspected cases occur in vaccinated persons. PMID:25483547

  15. Aflatoxin Exposure and Viral Hepatitis in the Etiology of Liver Cirrhosis in The Gambia, West Africa

    PubMed Central

    Kuniholm, Mark H.; Lesi, Olufunmilayo A.; Mendy, Maimuna; Akano, Aliu O.; Sam, Omar; Hall, Andrew J.; Whittle, Hilton; Bah, Ebrima; Goedert, James J.; Hainaut, Pierre; Kirk, Gregory D.

    2008-01-01

    Background Cirrhosis of the liver is thought to be a major cause of morbidity and mortality in sub-Saharan Africa, but few controlled studies on the etiology of cirrhosis have been conducted in this region. Objectives We aimed to elucidate the association between environmental and infectious exposures and cirrhosis in The Gambia. Methods Ninety-seven individuals were diagnosed with cirrhosis using a validated ultrasound scoring system and were compared with 397 controls. Participants reported demographic and food frequency information. Blood samples were tested for hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), hepatitis C virus (HCV) antibody, HCV RNA, and the aflatoxin-associated 249ser TP53 mutation. Results HBsAg seropositivity was associated with a significant increase in risk of cirrhosis [odds ratio (OR) = 8.0; 95% confidence interval (CI), 4.4–14.7] as was the presence of HBeAg (OR = 10.3; 95% CI, 2.0–53.9) and HCV infection (OR = 3.3; 95% CI, 1.2–9.5). We present novel data that exposure to aflatoxin, as assessed both by high lifetime groundnut (peanut) intake and by the presence of the 249ser TP53 mutation in plasma, is associated with a significant increase in the risk for cirrhosis (OR = 2.8; 95% CI, 1.1–7.7 and OR = 3.8; 95% CI, 1.5–9.6, respectively). Additionally, aflatoxin and hepatitis B virus exposure appeared to interact synergistically to substantially increase the risk of cirrhosis, although this was not statistically significant. Conclusions Our results suggest that the spectrum of morbidity associated with aflatoxin exposure could include cirrhosis. PMID:19057710

  16. Viral and Bacterial Etiology of Acute Diarrhea among Children under 5 Years of Age in Wuhan, China

    PubMed Central

    Zhu, Xu-Hui; Tian, Lei; Cheng, Zhong-Ju; Liu, Wei-Yong; Li, Song; Yu, Wei-Ting; Zhang, Wen-Qian; Xiang, Xu; Sun, Zi-Yong

    2016-01-01

    Background: Acute diarrhea remains the serious problem in developing countries, especially among children under 5 years of age. Currently, only two or three common diarrhea pathogens were screened at most hospitals in China. The aim of this study was to provide a wide variety of diarrhea pathogens and their antimicrobial resistance patterns in children under 5 years of age. Methods: Totally 381 stool samples collected from Tongji Hospital between July 1, 2014 and June 30, 2015 were tested by culture and/or polymerase chain reaction for eight kinds of bacteria and five kinds of viruses. An antimicrobial sensitivity test was performed using dilution method recommended by the Clinical and Laboratory Standards Institute. Results: Viral infections were mainly identified in infants (0–11 months), whereas bacterial infections were more prevalent in the age of 24–59 months. About 69.8% of samples were positive for at least one pathogen, 51.7% of samples were virus positive, followed by bacteria positive cases (19.4%), and 12.6% of cases displayed co-infections with two viruses or a virus and a bacterium. Rotavirus was the most prevalent pathogen, followed closely by norovirus, while Salmonella was the most commonly isolated bacteria, followed by diarrheagenic Escherichia coli (DEC) and Campylobacter. More than 40% of Salmonella spp. and DEC isolates were resistant to first-line antibiotics (ampicillin, trimethoprim-sulfamethoxazole, and tetracycline). Around 10% of Salmonella spp. isolates were resistant to ceftriaxone and ciprofloxacin simultaneously. Campylobacter spp. displayed high resistance to ciprofloxacin but kept low resistance to azithromycin and doxycycline. Conclusions: The etiology of acute diarrhea varies in children of different age groups. The high frequency of infection with viruses suggests the urgent demand for new viral vaccine development. Proper use of antibiotics in the treatment of acute diarrhea is crucial due to the high level of antibiotic

  17. Etiology and Incidence of Viral Acute Respiratory Infections Among Refugees Aged 5 Years and Older in Hagadera Camp, Dadaab, Kenya.

    PubMed

    Mohamed, Gedi A; Ahmed, Jamal A; Marano, Nina; Mohamed, Abdinoor; Moturi, Edna; Burton, Wagacha; Otieno, Samora; Fields, Barry; Montgomery, Joel; Kabugi, Willy; Musa, Hashim; Cookson, Susan T

    2015-12-01

    We used the Centers for Disease Control and Prevention-Kenya Medical Research Institute Acute Respiratory Infection (ARI) Surveillance System data to estimate severe acute respiratory infection (SARI) hospitalization rates, viral etiology, and associated complaints of influenza-like illnesses (ILI) and SARI conditions among those aged 5 years and older in Hagadera, Dadaab refugee camp, Kenya, for 2010-2012. A total of 471 patients aged ≥ 5 years met the case definition for ILI or SARI. SARI hospitalization rates per 10,000 person-years were 14.7 (95% confidence interval [CI] = 9.1, 22.2) for those aged 5-14 years; 3.4 (95% CI = 1.6, 7.2) for those aged 15-24 year; and 3.8 (95% CI = 1.6, 7.2) for those aged ≥ 25 years. Persons between the ages of 5 and 14 years had 3.5 greater odds to have been hospitalized as a result of SARI than those aged ≥ 25 years (odds ratio [OR] = 3.5, P < 0.001). Among the 419 samples tested, 169 (40.3%) were positive for one or more virus. Of those samples having viruses, 36.9% had influenza A; 29.9% had adenovirus; 20.2% had influenza B; and 14.4% had parainfluenza 1, 2, or 3. Muscle/joint pain was associated with influenza A (P = 0.002), whereas headache was associated with influenza B (P = 0.019). ARIs were responsible for a substantial disease burden in Hagadera camp. PMID:26458776

  18. Mate-Pair Sequencing as a Powerful Clinical Tool for the Characterization of Cancers with a DNA Viral Etiology

    PubMed Central

    Gao, Ge; Smith, David I.

    2015-01-01

    DNA viruses are known to be associated with a variety of different cancers. Human papillomaviruses (HPV) are a family of viruses and several of its sub-types are classified as high-risk HPVs as they are found to be associated with the development of a number of different cancers. Almost all cervical cancers appear to be driven by HPV infection and HPV is also found in most cancers of the anus and at least half the cancers of the vulva, penis and vagina, and increasingly found in one sub-type of head and neck cancers namely oropharyngeal squamous cell carcinoma. Our understanding of HPVs role in cancer development comes from extensive studies done on cervical cancer and it has just been assumed that HPV plays an identical role in the development of all other cancers arising in the presence of HPV sequences, although this has not been proven. Most invasive cervical cancers have the HPV genome integrated into one or more sites within the human genome. One powerful tool to examine all the sites of HPV integration in a cancer but that also provides a comprehensive view of genomic alterations in that cancer is the use of next generation sequencing of mate-pair libraries produced from the DNA isolated. We will describe how this powerful technology can provide important information about the genomic organization within an individual cancer genome, and how this has demonstrated that HPVs role in oropharyngeal squamous cell carcinoma is distinct from that in cervical cancer. We will also describe why the sequencing of mate-pair libraries could be a powerful clinical tool for the management of patients with a DNA viral etiology and how this could quickly transform the care of these patients. PMID:26262638

  19. Mate-Pair Sequencing as a Powerful Clinical Tool for the Characterization of Cancers with a DNA Viral Etiology.

    PubMed

    Gao, Ge; Smith, David I

    2015-08-01

    DNA viruses are known to be associated with a variety of different cancers. Human papillomaviruses (HPV) are a family of viruses and several of its sub-types are classified as high-risk HPVs as they are found to be associated with the development of a number of different cancers. Almost all cervical cancers appear to be driven by HPV infection and HPV is also found in most cancers of the anus and at least half the cancers of the vulva, penis and vagina, and increasingly found in one sub-type of head and neck cancers namely oropharyngeal squamous cell carcinoma. Our understanding of HPVs role in cancer development comes from extensive studies done on cervical cancer and it has just been assumed that HPV plays an identical role in the development of all other cancers arising in the presence of HPV sequences, although this has not been proven. Most invasive cervical cancers have the HPV genome integrated into one or more sites within the human genome. One powerful tool to examine all the sites of HPV integration in a cancer but that also provides a comprehensive view of genomic alterations in that cancer is the use of next generation sequencing of mate-pair libraries produced from the DNA isolated. We will describe how this powerful technology can provide important information about the genomic organization within an individual cancer genome, and how this has demonstrated that HPVs role in oropharyngeal squamous cell carcinoma is distinct from that in cervical cancer. We will also describe why the sequencing of mate-pair libraries could be a powerful clinical tool for the management of patients with a DNA viral etiology and how this could quickly transform the care of these patients. PMID:26262638

  20. [Pathogenetic ground of including reamberin and cycloferon combination into the therapy program for patients with severe cases of acute tonsillitis of a mixed viral/bacterial etiology].

    PubMed

    Frolov, V M; Peresadin, N A; Tereshin, V A; Chkhetiani, R B; Kruglova, O V

    2012-03-01

    The increase of severe cases of acute tonsillitis (AT) is presently marked. Severe cases of AT disturb immune and metabolic homoeostasis initiating the development of disease. Therapy optimization is required to select the best treatment. In patients with severe cases of AT of mixed viral/bacterial etiology before the treatment it is revealed the increase of general activity of lactatedehydrigenase (LDH) and increase of the level of cathode "anaerobic" factions LDH4+5 and the decline of concentration ATP in the blood. There was a compensatory rise of level of ADP and АМP. The substantial decline of serum interferon (CIF) activity and diminishing maintenance of α-interferon (α-IFN) and γ-interferon (γ-IFN) in the blood of the patients, that testified to oppressing of interferonogenesis. Treatment of severe cases of AT of mixed viral/bacterial etiology of modern detoxic preparation reamberin and immunoactive preparation cycloferon combination positively influences the studied laboratory indexes. The improvement of power metabolism is marked, that was characterized by normalization of level adenine nucleotides (ATP, АDP, АМP) and general activity of LDH and its izoenzimes spectrum. At the same time the increase of CIF level is set, maintenances α-IFN and γ-IFN in the blood, that testified to the improvement of interferonogenesis. The results demonstrate the therapeutic potential of reamberin and cycloferon combination for treatment of patients with AT of mixed viral/bacterial etiology. PMID:22573749

  1. The peritoneal macrophage inflammatory profile in cirrhosis depends on the alcoholic or hepatitis C viral etiology and is related to ERK phosphorylation

    PubMed Central

    2012-01-01

    Background The development of ascites in cirrhotic patients generally heralds a deterioration in their clinical status. A differential gene expression profile between alcohol- and hepatitis C virus (HCV)-related cirrhosis has been described from liver biopsies, especially those associated with innate immune responses. The aim of this work was to identify functional differences in the inflammatory profile of monocyte-derived macrophages from ascites in cirrhotic patients of different etiologies in an attempt to extrapolate studies from liver biopsies to immune cells in ascites. To this end 45 patients with cirrhosis and non-infected ascites, distributed according to disease etiology, HCV (n = 15) or alcohol (n = 30) were studied. Cytokines and the cell content in ascites were assessed by ELISA and flow cytometry, respectively. Cytokines and ERK phosphorylation in peritoneal monocyte-derived macrophages isolated and stimulated in vitro were also determined. Results A different pattern of leukocyte migration to the peritoneal cavity and differences in the primed status of macrophages in cirrhosis were observed depending on the viral or alcoholic etiology. Whereas no differences in peripheral blood cell subpopulations could be observed, T lymphocyte, monocyte and polymorphonuclear cell populations in ascites were more abundant in the HCV than the alcohol etiology. HCV-related cirrhosis etiology was associated with a decreased inflammatory profile in ascites compared with the alcoholic etiology. Higher levels of IL-10 and lower levels of IL-6 and IL-12 were observed in ascitic fluid from the HCV group. Isolated peritoneal monocyte-derived macrophages maintained their primed status in vitro throughout the 24 h culture period. The level of ERK1/2 phosphorylation was higher in ALC peritoneal macrophages at baseline than in HCV patients, although the addition of LPS induced a greater increase in ERK1/2 phosphorylation in HCV than in ALC patients. Conclusions The

  2. Bovine viral diarrhea virus in postweaned calves in a feedlot after vaccination and from fatal respiratory cases: isolation and differentiation of MLV BVDV and field strains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viral infections are important etiologies in BRD cases. Calves at stocker/feedlot entry usually receive modified live viral (MLV) vaccines containing bovine herpesvirus-1 (BoHV-1), parainfluenza-3 virus (PI3V), bovine viral diarrhea viruses (BVDV), and bovine respiratory syncytial virus (BRSV). In...

  3. Viral etiology of hospitalized acute lower respiratory infections in children under 5 years of age – a systematic review and meta-analysis

    PubMed Central

    Lukšić, Ivana; Kearns, Patrick K; Scott, Fiona; Rudan, Igor; Campbell, Harry; Nair, Harish

    2013-01-01

    Aim To estimate the proportional contribution of influenza viruses (IV), parainfluenza viruses (PIV), adenoviruses (AV), and coronaviruses (CV) to the burden of severe acute lower respiratory infections (ALRI). Methods The review of the literature followed PRISMA guidelines. We included studies of hospitalized children aged 0-4 years with confirmed ALRI published between 1995 and 2011. A total of 51 studies were included in the final review, comprising 56 091 hospitalized ALRI episodes. Results IV was detected in 3.0% (2.2%-4.0%) of all hospitalized ALRI cases, PIV in 2.7% (1.9%-3.7%), and AV in 5.8% (3.4%-9.1%). CV are technically difficult to culture, and they were detected in 4.8% of all hospitalized ALRI patients in one study. When respiratory syncytial virus (RSV) and less common viruses were included, at least one virus was detected in 50.4% (40.0%-60.7%) of all hospitalized severe ALRI episodes. Moreover, 21.9% (17.7%-26.4%) of these viral ALRI were mixed, including more than one viral pathogen. Among all severe ALRI with confirmed viral etiology, IV accounted for 7.0% (5.5%-8.7%), PIV for 5.8% (4.1%-7.7%), and AV for 8.8% (5.3%-13.0%). CV was found in 10.6% of virus-positive pneumonia patients in one study. Conclusions This article provides the most comprehensive analysis of the contribution of four viral causes to severe ALRI to date. Our results can be used in further cost-effectiveness analyses of vaccine development and implementation for a number of respiratory viruses. PMID:23630140

  4. Comparison of Epstein-Barr virus strains of different origin by analysis of the viral DNAs.

    PubMed Central

    Bornkamm, G W; Delius, H; Zimber, U; Hudewentz, J; Epstein, M A

    1980-01-01

    Epstein-Barr virus (EBV) originating from Burkitt's lymphoma (P3HR-1 and CC34-5), nasopharyngeal carcinoma (M-ABA), transfusion mononucleosis (B95-8), and a patient with acute myeloblastic leukemia (QIMR-WIL) was isolated from virus-carrying lymphoid cell lines after induction with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate. Viral DNA was analyzed by partial denaturation mapping and by use of the restriction endonucleases EcoRI, HindIII, and SalI and separation of fragments in 0.4% agarose. By using the restriction enzyme data of B95-8 (EBV) and W91 (EBV) obtained by Given and Kieff (D. Given and E. Kieff, J. Virol. 28:524-542, 1978), maps were established for the other virus strains. Comigrating fragments were assumed to be identical or closely related among the different strains. Fragments of different strains migrating differently were isolated, purified, radioactively labeled, and mapped by hybridization against blots of separated viral fragments. The results were as follows. (i) All strains studied were closely related. (ii) The number of internal repeats was variable among and within viral strains. (iii) B95-8 (EBV) was the only strain with a large deletion of about 12,000 base pairs at the right-hand side of the molecule. At the same site, small deletions of about 400 to 500 base pairs were observed in P3HR-1 (EBV) and M-ABA (EBV) DNA. (iv) P3HR-1 (EBV), the only nontransforming EBV strain, had a deletion of about 3,000 to 4,000 base pairs in the long unique region adjacent to the internal repeats carrying a HindIII site. (v) Small inserted sequences of 150 to 400 base pairs were observed in M-ABA (EBV) and B95-8 (EBV) at identical sites in the middle of the long unique region. (vi) Near this site, an insertion of about 1,000 base pairs was found in P3HR-1 (EBV) DNA. (vii) The cleavage patterns of P3HR-1 virus DNA and the results of blot hybridizations with P3HR-1 virus fragments are not conclusive and point to the possibility that in addition

  5. Viral etiology of acute lower respiratory tract infections in hospitalized young children in a children's referral hospital in Iran.

    PubMed

    Pourakbari, Babak; Mahmoudi, Shima; Movahedi, Zahra; Halimi, Shahnaz; Momeni, Shervin; Hosseinpour-Sadeghi, Reihaneh; Mamishi, Setareh

    2014-01-01

    Viruses are considered major causes of acute respiratory tract infections among children under 5 years old. In this study we investigated the prevalence of three respiratory viruses--respiratory syncytial virus (RSV), influenza virus (INF) and adenovirus (ADV)--among hospitalized children with acute viral lower respiratory tract infections (LRTIs). Nasopharyngeal aspirates were collected from children under five who had been hospitalized for LRTIs. The clinical data, including demographic data (age and sex), vital symptoms and signs at admission, duration of fever, duration of hospitalization, chest X-ray findings and outcome were considered. All inpatient specimens were tested by reverse transcriptase-polymerase chain reaction (RT-PCR) for RSV and the INF-A, INF-B and parainfluenza viruses and by polymerase chain reaction (PCR) for ADV. Out of those from 232 patients, 58 (25%) specimens were positive for either RSV, INF or ADV. The most predominant pathogens were RSV (40 cases, 17.2%), followed by INF (10 cases, 4%; including 8 type A and 2 type B) and ADV (8 cases, 3.4%). A total of 32 (55.1%) viral cases were identified in the spring, followed by 19 (32.7%) in the autumn and 7 (12%) in the winter. There was no significant correlation between clinical symptoms and the individual virus detected. In our study, RSV and INF were the two most common causes of LRTIs. These data are helpful for guiding the development of further vaccines as well as the use of antiviral drugs. Further studies will be needed to investigate other respiratory viruses such as parainfluenza, human metapneumovirus and rhinovirus. PMID:25818953

  6. Vibrio coralliilyticus strain OCN008 is an etiological agent of acute Montipora white syndrome.

    PubMed

    Ushijima, Blake; Videau, Patrick; Burger, Andrew H; Shore-Maggio, Amanda; Runyon, Christina M; Sudek, Mareike; Aeby, Greta S; Callahan, Sean M

    2014-04-01

    Identification of a pathogen is a critical first step in the epidemiology and subsequent management of a disease. A limited number of pathogens have been identified for diseases contributing to the global decline of coral populations. Here we describe Vibrio coralliilyticus strain OCN008, which induces acute Montipora white syndrome (aMWS), a tissue loss disease responsible for substantial mortality of the coral Montipora capitata in Kāne'ohe Bay, Hawai'i. OCN008 was grown in pure culture, recreated signs of disease in experimentally infected corals, and could be recovered after infection. In addition, strains similar to OCN008 were isolated from diseased coral from the field but not from healthy M. capitata. OCN008 repeatedly induced the loss of healthy M. capitata tissue from fragments under laboratory conditions with a minimum infectious dose of between 10(7) and 10(8) CFU/ml of water. In contrast, Porites compressa was not infected by OCN008, indicating the host specificity of the pathogen. A decrease in water temperature from 27 to 23°C affected the time to disease onset, but the risk of infection was not significantly reduced. Temperature-dependent bleaching, which has been observed with the V. coralliilyticus type strain BAA-450, was not observed during infection with OCN008. A comparison of the OCN008 genome to the genomes of pathogenic V. coralliilyticus strains BAA-450 and P1 revealed similar virulence-associated genes and quorum-sensing systems. Despite this genetic similarity, infections of M. capitata by OCN008 do not follow the paradigm for V. coralliilyticus infections established by the type strain. PMID:24463971

  7. Virulent Properties of Russian Bovine Viral Diarrhea Virus Strains in Experimentally Infected Calves.

    PubMed

    Glotov, Alexander G; Glotova, Tatyana I; Koteneva, Svetlana V; Semenova, Olga V; Sergeev, Alexander A; Titova, Ksenya A; Morozova, Anastasia A; Sergeev, Artemiy A

    2016-01-01

    The results of experimental study of three noncytopathic and two cytopathic bovine viral diarrhea virus (BVDV) strains isolated from cattle in the Siberian region and belonging to the type 1 (subtypes 1a, 1b, and 1d) have been presented. All investigated strains caused the development of infectious process in the seronegative 4-6-month-old calves after aerosol challenge with the dose of 6 log10 TCID50. The greatest virulence had noncytopathic strain and cytopathic strain related to the subtypes 1d and 1b, respectively. All strains in infected calves caused some signs of moderate acute respiratory disease and diarrhea: depression 3-5 days postinfection (p.i.), refusal to food, severe hyperthermia to 41.9°С, serous exudate discharges from the nasal cavity and eyes, transient diarrhea with blood, leukopenia (up to 2700 cells/mm(3)), and macroscopic changes in the respiratory organs and intestine. The infected animals recovered from 12 to 15 days p.i. and in 90% cases formed humoral immune response 25 days p.i. (antibody titers to BVDV: 1 : 4-1 : 16). Our results confirmed the presence of virulent BVDV1 strains and showed the need for researches on the molecular epidemiology of the disease, development of more effective diagnostic systems, and optimization of control programs with use of vaccines. PMID:27190687

  8. Virulent Properties of Russian Bovine Viral Diarrhea Virus Strains in Experimentally Infected Calves

    PubMed Central

    Koteneva, Svetlana V.; Semenova, Olga V.; Sergeev, Alexander A.; Titova, Ksenya A.; Morozova, Anastasia A.

    2016-01-01

    The results of experimental study of three noncytopathic and two cytopathic bovine viral diarrhea virus (BVDV) strains isolated from cattle in the Siberian region and belonging to the type 1 (subtypes 1a, 1b, and 1d) have been presented. All investigated strains caused the development of infectious process in the seronegative 4–6-month-old calves after aerosol challenge with the dose of 6 log10 TCID50. The greatest virulence had noncytopathic strain and cytopathic strain related to the subtypes 1d and 1b, respectively. All strains in infected calves caused some signs of moderate acute respiratory disease and diarrhea: depression 3–5 days postinfection (p.i.), refusal to food, severe hyperthermia to 41.9°С, serous exudate discharges from the nasal cavity and eyes, transient diarrhea with blood, leukopenia (up to 2700 cells/mm3), and macroscopic changes in the respiratory organs and intestine. The infected animals recovered from 12 to 15 days p.i. and in 90% cases formed humoral immune response 25 days p.i. (antibody titers to BVDV: 1 : 4–1 : 16). Our results confirmed the presence of virulent BVDV1 strains and showed the need for researches on the molecular epidemiology of the disease, development of more effective diagnostic systems, and optimization of control programs with use of vaccines. PMID:27190687

  9. Did medieval trade activity and a viral etiology control the spatial extent and seasonal distribution of Black Death mortality?

    PubMed

    Bossak, Brian H; Welford, Mark R

    2009-06-01

    Recent research into the world's greatest recorded epidemic, the Medieval Black Death (MBD), has cast doubt on Bubonic Plague as the etiologic agent. Prior research has recently culminated in outstanding advances in our understanding of the spatio-temporal pattern of MBD mortality, and a characterization of the incubation, latent, infectious, and symptomatic periods of the MBD. However, until now, several mysteries remained unexplained, including perhaps the biggest quandary of all: why did the MBD exhibit inverse seasonal peaks in mortality from diseases recorded in modern times, such as seasonal Influenza or the Indian Plague Epidemics of the early 1900 s? Although some have argued that climate changes likely explain the observed differences between modern clinical Bubonic Plague seasonality and MBD mortality accounts, we believe that another factor explains these dissimilarities. Here, we provide a synthetic hypothesis which builds upon previous theories developed in the last ten years or so. Our all-encompassing theory explains the causation, dissemination, and lethality of the MBD. We theorize that the MBD was a human-to-human transmitted virus, originating in East-Central Asia and not Africa (as some recent work has proposed), and that its areal extent during the first great epidemic wave of 1347-1350 was controlled hierarchically by proximity to trade routes. We also propose that the seasonality of medieval trade controlled the warm-weather mortality peaks witnessed during 1347-1350; during the time of greatest market activity, traders, fairgoers, and religious pilgrims served as unintentional vectors of a lethal virus with an incubation period of approximately 32 days, including a largely asymptomatic yet infectious period of roughly three weeks. We include a description of the rigorous research agenda that we have proposed in order to subject our theory to scientific scrutiny and a description of our plans to generate the first publicly available

  10. Viral etiology of medically attended influenza-like illnesses in children less than five years old in Suzhou, China, 2011-2014.

    PubMed

    Wang, Dan; Chen, Liling; Ding, Yunfang; Zhang, Jun; Hua, Jun; Geng, Qian; Ya, Xuerong; Zeng, Shanshan; Wu, Jing; Jiang, Yanwei; Zhang, Tao; Zhao, Genming

    2016-08-01

    Limited information is available on the non-influenza etiology and epidemiology of influenza-like illness (ILI) in China. From April 2011 to March 2014, we collected oropharyngeal swabs from children less than 5 years of age with symptoms of ILI who presented to the outpatient departments of Suzhou University Affiliated Children's Hospital (SCH). We used reverse transcription polymerase chain reaction (rt-PCR) or PCR to detect 11 respiratory viruses. Among 3,662 enrolled ILI patients, 1,292 (35.3%) tested positive for at least one virus. Influenza virus (16.9%) was detected most frequently (influenza A 7.4%, influenza B 9.5%), followed by respiratory syncytial virus (RSV) (5.6%), parainfluenza virus (PIV) types 1-4 (4.8%), human bocavirus (HBoV) (3.8%), human metapneumovirus (HMPV) (3.5%), and adenovirus (ADV) (3.0%). Co-infections were identified in 108 (2.9%) patients. Influenza virus predominantly circulated in January-March and June-July. The 2013-2014 winter peaks of RSV and influenza overlapped. Compared with other virus positive cases, influenza positive cases were more likely to present with febrile seizure, and RSV positive cases were more likely to present with cough and wheezing, and were most frequently diagnosed with pneumonia. These data provide a better understanding of the viral etiology of ILI among children less than 5 years of age in Suzhou, China. Influenza is not only the most frequently identified pathogen but it is also the only vaccine preventable illness among the 11 pathogens tested. Such findings suggest the potential value of exploring value of influenza vaccination among this influenza vaccination target group. J. Med. Virol. 88:1334-1340, 2016. © 2016 Wiley Periodicals, Inc. PMID:26792409

  11. Accurate reconstruction of viral quasispecies spectra through improved estimation of strain richness

    PubMed Central

    2015-01-01

    Background Estimating the number of different species (richness) in a mixed microbial population has been a main focus in metagenomic research. Existing methods of species richness estimation ride on the assumption that the reads in each assembled contig correspond to only one of the microbial genomes in the population. This assumption and the underlying probabilistic formulations of existing methods are not useful for quasispecies populations where the strains are highly genetically related. The lack of knowledge on the number of different strains in a quasispecies population is observed to hinder the precision of existing Viral Quasispecies Spectrum Reconstruction (QSR) methods due to the uncontrolled reconstruction of a large number of in silico false positives. In this work, we formulated a novel probabilistic method for strain richness estimation specifically targeting viral quasispecies. By using this approach we improved our recently proposed spectrum reconstruction pipeline ViQuaS to achieve higher levels of precision in reconstructed quasispecies spectra without compromising the recall rates. We also discuss how one other existing popular QSR method named ShoRAH can be improved using this new approach. Results On benchmark data sets, our estimation method provided accurate richness estimates (< 0.2 median estimation error) and improved the precision of ViQuaS by 2%-13% and F-score by 1%-9% without compromising the recall rates. We also demonstrate that our estimation method can be used to improve the precision and F-score of ShoRAH by 0%-7% and 0%-5% respectively. Conclusions The proposed probabilistic estimation method can be used to estimate the richness of viral populations with a quasispecies behavior and to improve the accuracy of the quasispecies spectra reconstructed by the existing methods ViQuaS and ShoRAH in the presence of a moderate level of technical sequencing errors. Availability http://sourceforge.net/projects/viquas/ PMID:26678073

  12. Mitotic stability and nuclear inheritance of integrated viral cDNA in engineered hypovirulent strains of the chestnut blight fungus.

    PubMed Central

    Chen, B; Choi, G H; Nuss, D L

    1993-01-01

    Transmissible hypovirulence is a novel form of biological control in which virulence of a fungal pathogen is attenuated by an endogenous RNA virus. The feasibility of engineering hypovirulence was recently demonstrated by transformation of the chestnut blight fungus, Cryphonectria parasitica, with a full-length cDNA copy of a hypovirulence-associated viral RNA. Engineered hypovirulent transformants were found to contain both a chromsomally integrated cDNA copy of the viral genome and a resurrected cytoplasmically replicating double-stranded RNA form. We now report stable maintenance of integrated viral cDNA through repeated rounds of asexual sporulation and passages on host plant tissue. We also demonstrate stable nuclear inheritance of the integrated viral cDNA and resurrection of the cytoplasmic viral double-stranded RNA form in progeny resulting from the mating of an engineered hypovirulent C. parasitica strain and a vegetatively incompatible virulent strain. Mitotic stability of the viral cDNA ensures highly efficient transmission of the hypovirulence phenotype through conidia. Meiotic transmission, a mode not observed for natural hypovirulent strains, introduces virus into ascospore progeny representing a spectrum of vegetative compatibility groups, thereby circumventing barriers to anastomosis-mediated transmission imposed by the fungal vegetative incompatibility system. These transmission properties significantly enhance the potential of engineered hypovirulent C. parasitica strains as effective biocontrol agents. Images PMID:8344241

  13. NEP: web server for epitope prediction based on antibody neutralization of viral strains with diverse sequences.

    PubMed

    Chuang, Gwo-Yu; Liou, David; Kwong, Peter D; Georgiev, Ivelin S

    2014-07-01

    Delineation of the antigenic site, or epitope, recognized by an antibody can provide clues about functional vulnerabilities and resistance mechanisms, and can therefore guide antibody optimization and epitope-based vaccine design. Previously, we developed an algorithm for antibody-epitope prediction based on antibody neutralization of viral strains with diverse sequences and validated the algorithm on a set of broadly neutralizing HIV-1 antibodies. Here we describe the implementation of this algorithm, NEP (Neutralization-based Epitope Prediction), as a web-based server. The users must supply as input: (i) an alignment of antigen sequences of diverse viral strains; (ii) neutralization data for the antibody of interest against the same set of antigen sequences; and (iii) (optional) a structure of the unbound antigen, for enhanced prediction accuracy. The prediction results can be downloaded or viewed interactively on the antigen structure (if supplied) from the web browser using a JSmol applet. Since neutralization experiments are typically performed as one of the first steps in the characterization of an antibody to determine its breadth and potency, the NEP server can be used to predict antibody-epitope information at no additional experimental costs. NEP can be accessed on the internet at http://exon.niaid.nih.gov/nep. PMID:24782517

  14. Polymorphism of viral dsRNA in Xanthophyllomyces dendrorhous strains isolated from different geographic areas

    PubMed Central

    Baeza, Marcelo; Sanhueza, Mario; Flores, Oriana; Oviedo, Vicente; Libkind, Diego; Cifuentes, Víctor

    2009-01-01

    Background Strains of the astaxanthin producing yeast Xanthophyllomyces dendrorhous have been isolated from different cold regions around the earth, and the presence of double stranded RNA (dsRNA) elements was described in some isolates. This kind of viruses is widely distributed among yeasts and filamentous fungi and, although generally are cryptic in function, their studies have been a key factor in the knowledge of important fungi. In this work, the characterization and genetic relationships among dsRNA elements were determined in strains representatives of almost all regions of the earth where X. dendrorhous have been isolated. Results Almost all strains of X. dendrorhous analyzed carry one, two or four dsRNA elements, of molecular sizes in the range from 0.8 to 5.0 kb. Different dsRNA-patterns were observed in strains with different geographic origin, being L1 (5.0 kb) the common dsRNA element. By hybridization assays a high genomic polymorphism was observed among L1 dsRNAs of different X. dendrorhous strains. Contrary, hybridization was observed between L1 and L2 dsRNAs of strains from same or different regions, while the dsRNA elements of minor sizes (M, S1, and S2) present in several strains did not show hybridization with neither L1 or L2 dsRNAs. Along the growth curve of UCD 67-385 (harboring four dsRNAs) an increase of L2 relative to L1 dsRNA was observed, whiles the S1/L1 ratio remains constant, as well as the M/L1 ratio of Patagonian strain. Strains cured of S2 dsRNA were obtained by treatment with anisomycin, and comparison of its dsRNA contents with uncured strain, revealed an increase of L1 dsRNA while the L2 and S1 dsRNA remain unaltered. Conclusion The dsRNA elements of X. dendrorhous are highly variable in size and sequence, and the dsRNA pattern is specific to the geographic region of isolation. Each L1 and L2 dsRNA are viral elements able to self replicate and to coexist into a cell, and L1 and S2 dsRNAs elements could be part of a helper

  15. Novel Trichoderma polysporum Strain for the Biocontrol of Pseudogymnoascus destructans, the Fungal Etiologic Agent of Bat White Nose Syndrome.

    PubMed

    Zhang, Tao; Chaturvedi, Vishnu; Chaturvedi, Sudha

    2015-01-01

    White-nose syndrome (WNS), an emerging disease of hibernating bats, has rapidly spread across eastern North America killing millions of bats. Pseudogymnoascus destructans (Pd), the sole etiologic agent of WNS, is widespread and persistent in bat hibernacula. Control of Pd in the affected sites is urgently needed to break the transmission cycle while minimizing any adverse impact on the native organisms. We isolated a novel strain of Trichoderma polysporum (Tp) from one of the caves at the epicenter of WNS zoonotic. Detailed experimental studies revealed: (1) Tp WPM 39143 was highly adapted to grow at temperatures simulating the cave environment (6°C-15°C), (2) Tp WPM 39143 restricted Pd colony growth in dual culture challenges, (3) Tp WPM 39143 caused four logs reduction of Pd colony forming units and genome copies in autoclaved soil samples from one of the WNS affected caves, (4) Tp WPM 39143 extract showed specific fungicidal activity against Pd in disk diffusion assay, but not against closely related fungus P. pannorum (Pp), (5) Tp WPM 39143 extract retained inhibitory activity after exposure to high temperatures, light and proteinase K, and (6) Inhibitory metabolites in Tp WPM 39143 extract comprised of water-soluble, high polarity compounds. These results suggest that Tp WPM 39143 is a promising candidate for further evaluation as a biocontrol agent of Pd in WNS affected sites. PMID:26509269

  16. Novel Trichoderma polysporum Strain for the Biocontrol of Pseudogymnoascus destructans, the Fungal Etiologic Agent of Bat White Nose Syndrome

    PubMed Central

    Zhang, Tao; Chaturvedi, Vishnu; Chaturvedi, Sudha

    2015-01-01

    White-nose syndrome (WNS), an emerging disease of hibernating bats, has rapidly spread across eastern North America killing millions of bats. Pseudogymnoascus destructans (Pd), the sole etiologic agent of WNS, is widespread and persistent in bat hibernacula. Control of Pd in the affected sites is urgently needed to break the transmission cycle while minimizing any adverse impact on the native organisms. We isolated a novel strain of Trichoderma polysporum (Tp) from one of the caves at the epicenter of WNS zoonotic. Detailed experimental studies revealed: (1) Tp WPM 39143 was highly adapted to grow at temperatures simulating the cave environment (6°C-15°C), (2) Tp WPM 39143 restricted Pd colony growth in dual culture challenges, (3) Tp WPM 39143 caused four logs reduction of Pd colony forming units and genome copies in autoclaved soil samples from one of the WNS affected caves, (4) Tp WPM 39143 extract showed specific fungicidal activity against Pd in disk diffusion assay, but not against closely related fungus P. pannorum (Pp), (5) Tp WPM 39143 extract retained inhibitory activity after exposure to high temperatures, light and proteinase K, and (6) Inhibitory metabolites in Tp WPM 39143 extract comprised of water-soluble, high polarity compounds. These results suggest that Tp WPM 39143 is a promising candidate for further evaluation as a biocontrol agent of Pd in WNS affected sites. PMID:26509269

  17. Typing of cytopathic and noncytopathic bovine viral diarrhea virus reference and Canadian field strains using a neutralizing monoclonal antibody.

    PubMed Central

    Magar, R; Minocha, H C; Montpetit, C; Carman, P S; Lecomte, J

    1988-01-01

    Cytopathic and noncytopathic reference strains as well as Canadian field isolates of bovine viral diarrhea virus were analyzed by neutralization and immunofluorescence tests using a bovine viral diarrhea virus-specific neutralizing monoclonal antibody. Results on reference strains indicated three major antigenic groups: I) NADL-like, II) New York 1-like and III) Oregon C24V-like. Field isolates could be segregated into groups I and II and none could be typed into the group III. It appears that most bovine viral diarrhea virus strains share a common antigen which carries a major neutralization epitope. These characteristics would make this monoclonal antibody a useful reagent for taxonomic and epizootiological studies. Images Fig. 1. PMID:2450629

  18. Biochemical analysis of bovine viral diarrhea virus polypeptides and studies of strain variation

    SciTech Connect

    Raisch, K.P.

    1989-01-01

    Intracellular viral-specific polypeptides from the National Animal Disease Laboratory (NADL) strain of bovine viral diarrhea virus were studied by biosynthesis labelling, radioimmunoprecipitation (RIP), hypertonic initiation block (HIB) and polyacrylamide gel electrophoresis (PAGE). Eighteen virus-specific proteins were identified; thirteen were glycosylated (gp170, p135, p130, gp118, gp82, p80, gp74, gp63, gp60, p59, gp53, gp50, gp45, gp42, p37, gp32, gp25 and p22). When glycosylation was inhibited by tunicamycin, five {sup 35}S-methionine labelled proteins displayed increased electrophoretic mobility (gp170 to p165, gp74 to p66, gp53 to p45, gp50 to p42 and gp25 to p20) and four could not be identified. Similar shifts in mobility were observed following in vitro deglycosylation with endoglycosidases H and F indicating that the nine glycoproteins contained N-linked simple or high mannose containing moieties. Biosynthetic labelling in the presence of the ionophore, monensin, or in vitro deglycosylation with the endoglycosidase, O-glycanase, had no effect, which is consistent with the absence of O-linked carbohydrates in BVDV-specific proteins. N-linked glycosylation of BVDV proteins is critical for infectivity, because the virus from cells treated with tunicamycin was devoid of infectivity, whereas the virus from monensin-treated cells was fully infective. Partitioning of p130, p59, gp53-50, and p37 into solutions of Triton X-114 tentatively identified these molecules as partially hydrophobic transmembrane proteins. Biosynthesis in the presence of {sup 3}H-myristate and {sup 3}H-palmitate did not result in specifically labelled viral proteins indicating predominantly noncovalent nature of putative interactions of these proteins with membranes. Partial proteolytic peptide mapping revealed similarities among gp170, p130 and p80 and between gp53 and gp50.

  19. Complete Genome Sequence of Bovine Viral Diarrhea Virus-1 Strain Egy/Ismailia/2014, Subtype 1b.

    PubMed

    Soltan, Mohamed A; Wilkes, Rebecca P; Elsheery, Mohamed N; Elhaig, Mahmoud M; Riley, Matthew C; Kennedy, Melissa A

    2015-01-01

    Here, we report the complete genome sequence of bovine viral diarrhea virus-1b (BVDV-1b), strain Egy/Ismailia/2014. The virus genome is composed of 12,217 nucleotides organized as one open reading frame encoding 3,898 amino acids. This report will assist efforts in diagnostics, studying molecular epidemiology, and control of BVDV in Egypt. PMID:26701085

  20. Sequence Variability in Viral Genome Non-coding Regions Likely Contribute to Observed Differences in Viral Replication Amongst MARV Strains

    PubMed Central

    ALONSO, JESUS A.; PATTERSON, JEAN L.

    2013-01-01

    The Marburg viruses Musoke (MARV-Mus) and Angola (MARV-Ang) have highly similar genomic sequences. Analysis of viral replication using various assays consistently identified MARV-Ang as the faster replicating virus. Non-coding genomic regions of negative sense RNA viruses are known to play a role in viral gene expression. A comparison of the six non-coding regions using bicistronic minigenomes revealed that the first two non-coding regions (NP / VP35 and VP35 / VP40) differed significantly in their transcriptional regulation. Deletion mutation analysis of the MARV-Mus NP / VP35 region further revealed that the MARV polymerase (L) is able to initiate production of the downstream gene without the presence of highly conserved regulatory signals. Bicistronic minigenome assays also identified the VP30 mRNA 5′ untranslated region as an rZAP-targeted RNA motif. Overall, our studies indicate that the high variation of MARV non-coding regions may play a significant role in observed differences in transcription and/or replication. PMID:23510675

  1. Infectious Bovine Viral Diarrhea Virus (Strain NADL) RNA from Stable cDNA Clones: a Cellular Insert Determines NS3 Production and Viral Cytopathogenicity

    PubMed Central

    Mendez, Ernesto; Ruggli, Nicolas; Collett, Marc S.; Rice, Charles M.

    1998-01-01

    Bovine viral diarrhea virus (BVDV), strain NADL, was originally isolated from an animal with fatal mucosal disease. This isolate is cytopathic in cell culture and produces two forms of NS3-containing proteins: uncleaved NS2-3 and mature NS3. For BVDV NADL, the production of NS3, a characteristic of cytopathic BVDV strains, is believed to be a consequence of an in-frame insertion of a 270-nucleotide cellular mRNA sequence (called cIns) in the NS2 coding region. In this study, we constructed a stable full-length cDNA copy of BVDV NADL in a low-copy-number plasmid vector. As assayed by transfection of MDBK cells, uncapped RNAs transcribed from this template were highly infectious (>105 PFU/μg). The recovered virus was similar in plaque morphology, growth properties, polyprotein processing, and cytopathogenicity to the BVDV NADL parent. Deletion of cIns abolished processing at the NS2/NS3 site and produced a virus that was no longer cytopathic for MDBK cells. This deletion did not affect the efficiency of infectious virus production or viral protein production, but it reduced the level of virus-specific RNA synthesis and accumulation. Thus, cIns not only modulates NS3 production but also upregulates RNA replication relative to an isogenic noncytopathic derivative lacking the insert. These results raise the possibility of a linkage between enhanced BVDV NADL RNA replication and virus-induced cytopathogenicity. PMID:9573238

  2. Complete Genome Sequence of Bovine Viral Diarrhea Virus 2 Japanese Reference and Vaccine Strain KZ-91CP

    PubMed Central

    Sato, Asuka; Kameyama, Ken-ichiro; Tateishi, Kentaro; Ohmori, Keitaro; Todaka, Reiko; Katayama, Kazuhiko; Mizutani, Tetsuya; Yamakawa, Makoto; Shirai, Junsuke

    2015-01-01

    In this study, we report the complete genome sequence of the bovine viral diarrhea virus 2 Japanese reference strain KZ-91CP. The complete genome comprises 12,654 nucleotides and one open reading frame with 4,020 amino acids. A 369-nucleotide-long insertion encoding the chaperone protein DnaJ is found in the nonstructural 2 (NS2) coding region. PMID:25676770

  3. Complete Genome Sequence of Bovine Viral Diarrhea Virus 2 Japanese Reference and Vaccine Strain KZ-91CP.

    PubMed

    Sato, Asuka; Kameyama, Ken-Ichiro; Nagai, Makoto; Tateishi, Kentaro; Ohmori, Keitaro; Todaka, Reiko; Katayama, Kazuhiko; Mizutani, Tetsuya; Yamakawa, Makoto; Shirai, Junsuke

    2015-01-01

    In this study, we report the complete genome sequence of the bovine viral diarrhea virus 2 Japanese reference strain KZ-91CP. The complete genome comprises 12,654 nucleotides and one open reading frame with 4,020 amino acids. A 369-nucleotide-long insertion encoding the chaperone protein DnaJ is found in the nonstructural 2 (NS2) coding region. PMID:25676770

  4. [Genome sequencing and analysis of the bovine viral diarrhea virus-2 strain JZ05-1 isolated in China].

    PubMed

    Li, Qing-chao; Miao, Li-guang; Li, Hai-tao; Liu, Yan-huan; Zhang, Guang-lei; Xiao, Jia-mei

    2010-05-01

    Bovine viral diarrhea virus (BVDV) is a member of the genus Pestivirus, which is a widespread problem for beef and dairy herds, and has given rise to a significant loss in the livestock industry all over the world. The BVDV strain JZ05-1 isolated from cattle in Jilin, China generated cytopathic effect (CPE) in MDBK cells. Eight overlapped gene fragments were amplified by RT-PCR and sequenced, the complete genom sequence of BVDV strain JZ05-1 was assembled. According to the results, the JZ05-1 genome was composed of 12285 nucleotides in length (GenBank accession No. GQ888686), which could be divided into three regions: a 387 nt 5'-untranslated region (UTR), a 11694 nt single large open reading frame encoding a polyprotein, and a 204 nt 3'-UTR. The 5'-UTR and genome sequences were analyzed by sequence alignment and construction of phylogenetic trees. The strain JZ05-1 was classified as BVDV type 2a. The BVDV-2 strain JZ05-1 genome showed high similarity to the p11Q isolated in Canada and the XJ-04 isolated in China, with 90% and 91% identity in nucleotide sequence, respectively. Compared with the similarity within the BVDV-2 genotype (96%), the JZ05-1 had low sequence similarity to other BVDV-2 strains. PMID:20572347

  5. Analysis of Enterovirus 68 Strains from the 2014 North American Outbreak Reveals a New Clade, Indicating Viral Evolution

    PubMed Central

    Du, Juan; Zheng, Baisong; Zheng, Wenwen; Li, Peng; Kang, Jian; Hou, Jingwei; Markham, Richard; Zhao, Ke; Yu, Xiao-Fang

    2015-01-01

    Enterovirus 68 (EVD68) causes respiratory illness, mostly in children. Despite a reported low-level of transmission, the occurrence of several recent outbreaks worldwide including the 2014 outbreak in North America has raised concerns regarding the pathogenesis and evolution of EVD68. To elucidate the phylogenetic features of EVD68 and possible causes for the 2014 outbreak, 216 EVD68 strain sequences were retrieved from Genbank, including 22 from the 2014 outbreak. Several geographic and genotypic origins were established for these 22 strains, 19 of which were classified as Clade B. Of these 19 strains, 17 exhibited subsequent clustering and variation in protein residues involved in host-receptor interaction and/or viral antigenicity. Approximately 18 inter-clade variations were detected in VP1, which led to the identification of a new Clade D in EVD68 strains. The classification of this new clade was also verified by the re-construction of a Neighbor-Joining tree during the phylogenetic analysis. In addition, our results indicate that members of Clade B containing highly specific alterations in VP1 protein residues were the foremost contributors to the 2014 outbreak in the US. Altered host-receptor interaction and/or host immune recognition may explain the evolution of EVD68 as well as the global emergence and ongoing adaptation of this virus. PMID:26630383

  6. Analysis of Enterovirus 68 Strains from the 2014 North American Outbreak Reveals a New Clade, Indicating Viral Evolution.

    PubMed

    Du, Juan; Zheng, Baisong; Zheng, Wenwen; Li, Peng; Kang, Jian; Hou, Jingwei; Markham, Richard; Zhao, Ke; Yu, Xiao-Fang

    2015-01-01

    Enterovirus 68 (EVD68) causes respiratory illness, mostly in children. Despite a reported low-level of transmission, the occurrence of several recent outbreaks worldwide including the 2014 outbreak in North America has raised concerns regarding the pathogenesis and evolution of EVD68. To elucidate the phylogenetic features of EVD68 and possible causes for the 2014 outbreak, 216 EVD68 strain sequences were retrieved from Genbank, including 22 from the 2014 outbreak. Several geographic and genotypic origins were established for these 22 strains, 19 of which were classified as Clade B. Of these 19 strains, 17 exhibited subsequent clustering and variation in protein residues involved in host-receptor interaction and/or viral antigenicity. Approximately 18 inter-clade variations were detected in VP1, which led to the identification of a new Clade D in EVD68 strains. The classification of this new clade was also verified by the re-construction of a Neighbor-Joining tree during the phylogenetic analysis. In addition, our results indicate that members of Clade B containing highly specific alterations in VP1 protein residues were the foremost contributors to the 2014 outbreak in the US. Altered host-receptor interaction and/or host immune recognition may explain the evolution of EVD68 as well as the global emergence and ongoing adaptation of this virus. PMID:26630383

  7. International trades, local spread and viral evolution: the case of porcine circovirus type 2 (PCV2) strains heterogeneity in Italy.

    PubMed

    Franzo, Giovanni; Tucciarone, Claudia M; Dotto, Giorgia; Gigli, Alessandra; Ceglie, Letizia; Drigo, Michele

    2015-06-01

    Porcine circovirus type 2 is one of the most widespread and economically relevant infections of swine. Four genotypes have been recognized, but currently, only three (PCV2a, PCV2b and PCV2d) are effectively circulating. The widespread livestock trade and rapid viral evolution have contributed to determining the high heterogeneity of PCV2 and the dispersal of potentially more virulent strains. Italian swine farming and the related processing industry are relevant in the national economy. Despite the noteworthy losses associated with direct and control measure costs, no data are currently available on the molecular epidemiology of PCV2 in Italy. Our study, which was intended to fill this gap, considered 75 completed genome PCV2 sequences, which were obtained from samples collected from the highly densely populated area of Northern Italy between 2007 and 2014. Phylogenetic analysis and comparison with reference sequences demonstrated the co-circulation, with different prevalences, of PCV2a, PCV2b and PCV2d within the national borders, with PCV2b being the most prevalent. Recombination between different genotypes was also proven to be frequent. Phylogeographic analysis demonstrated that the marked variability of Italian PCV2 strains can be attributable to multiple introduction events. The comparison of the phylogenetic analysis results, the location of different haplotypes and the international commercial routs of live pigs allow the speculation of several links as well as the role of Italy as both an importer and exporter of PCV2 haplotypes, mainly from and to European and Asian countries. A similarly intricate contact network was demonstrated within national borders, with different haplotypes being detected in the same province and different provinces harbouring the same haplotype. Overall, this paper represents the first description of PCV2 in Italy and demonstrates that the high variability of circulating Italian strains is due to multiple introduction events, wide

  8. Host and geographic range extensions of the North American strain of viral hemorrhagic septicemia virus

    USGS Publications Warehouse

    Hedrick, R.P.; Batts, W.N.; Yun, S.; Traxler, G.S.; Kaufman, J.; Winton, J.R.

    2003-01-01

    Viral hemorrhagic septicemia virus (VHSV) was isolated from populations of Pacific sardine Sardinops sagaxfrom the coastal waters of Vancouver Island, British Columbia, Canada, and central and southern California, USA. The virus was also isolated from Pacific mackerel Scomber japonicus in southern California, from eulachon or smeltThaleichthys pacificus, and surf smelt Hypomesus pretiosus pretiosus from Oregon, USA. Mortality and skin lesions typical of viral hemorrhagic septicemia in other marine fish species were observed among sardine in Canada and in a few surf smelt from Oregon, but the remaining isolates of VHSV were obtained from healthy appearing fish. The prevalence of VHSV among groups of apparently healthy sardine, mackerel and smelt ranged from 4 to 8% in California and Oregon. A greater prevalence of infection (58%) occurred in groups of sardine sampled in Canada that sustained a naturally occurring epidemic during 1998-99. A captive group of surf smelt in Oregon exhibited an 81% prevalence of infection with clinical signs in only a few fish. The new isolates were confirmed as North American VHSV and were closely related based on comparisons of the partial nucleotide sequence of the glycoprotein (G) gene. The VHSV isolates from sardine in Canada and California were the most closely related, differing from isolates obtained from other marine fish species and salmonids in British Columbia, Canada, Alaska and Washington, USA. These new virus isolations extend both the known hosts (sardine, mackerel and 2 species of smelt) and geographic range (Oregon and California, USA) of VHSV.

  9. Variation in E**rns viral glycoprotein associated with failure of immunohistochemistry and commercial antigen capture ELISA to detect a field strain of bovine viral diarrhea virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine viral diarrhea virus (BVDV) effects cattle populations causing clinical signs that range from subclinical immunosuppression to severe reproductive and respiratory problems. Detection and removal of persistently infected (PI) calves is the single most important factor for control and eradicat...

  10. A bovine viral diarrhea virus type 1a strain in China: isolation, identification, and experimental infection in calves

    PubMed Central

    2014-01-01

    Background Bovine viral diarrhea virus (BVDV) is one of the most important pathogens in cattle. Previously, BVDV sub-genotypes of 1b, 1c, 1d, and 1 m were detected in China. However, isolation of BVDV type 1a from cattle has not been reported in China. In 2010, twenty nasal swabs and blood samples were collected from the cattle suspected BVDV infection in Henan province, China. A BVDV isolate was isolated using cell culture, and the pathogenesis of the virus isolate was studied. Methods Virus isolation was performed on MDBK cells. The virus identification was conducted by RT-PCR, neutralization test and immunofluorescence assay. In order to determine the genotype of the newly isolated virus, the 5′ un-translated region (5′UTR) of the virus isolate was cloned, sequenced and phylogenetically analyzed. To evaluate the virulence of the virus isolate, four BVDV sero-negative calves were intranasally inoculated with the virus suspension. Rectal temperatures and clinical signs were recorded daily. Blood samples were analyzed for changes in white blood cell counts, and tissue samples were taken for histopathology analysis. Results A new isolate of bovine viral diarrhea virus (BVDV), named HN01, was isolated from the nasal swabs using MDBK cell culture. The HN01 strain caused cytopathic effect (CPE) in MDBK cell cultures after two passages. The virus specifically reacted to BVDV1-specific monoclonal antibody in an immunofluorescence assay. A fragment of 288 bp of genome from this isolate was amplified by the RT-PCR. Phylogenetic analysis of 5′UTR indicated that the virus was BVDV 1a. In the pathogenesis study, four calves experimentally infected with the BVDV strain developed depression, cough and other clinical signs. Calves showed high temperature over 40°C, and white blood cell counts dropped more than 40%. Conclusions A new subgenotype 1a strain of BVDV was firstly isolated from dairy cattle in China. The experimental infection showed that the virus was

  11. Three-way interactions between mosquito population, viral strain and temperature underlying chikungunya virus transmission potential

    PubMed Central

    Zouache, Karima; Fontaine, Albin; Vega-Rua, Anubis; Mousson, Laurence; Thiberge, Jean-Michel; Lourenco-De-Oliveira, Ricardo; Caro, Valérie; Lambrechts, Louis; Failloux, Anna-Bella

    2014-01-01

    Interactions between pathogens and their insect vectors in nature are under the control of both genetic and non-genetic factors, yet most studies on mosquito vector competence for human pathogens are conducted in laboratory systems that do not consider genetic and/or environmental variability. Evaluating the risk of emergence of arthropod-borne viruses (arboviruses) of public health importance such as chikungunya virus (CHIKV) requires a more realistic appraisal of genetic and environmental contributions to vector competence. In particular, sources of variation do not necessarily act independently and may combine in the form of interactions. Here, we measured CHIKV transmission potential by the mosquito Aedes albopictus in all combinations of six worldwide vector populations, two virus strains and two ambient temperatures (20°C and 28°C). Overall, CHIKV transmission potential by Ae. albopictus strongly depended on the three-way combination of mosquito population, virus strain and temperature. Such genotype-by-genotype-by-environment (G × G × E) interactions question the relevance of vector competence studies conducted with a simpler set of conditions. Our results highlight the need to account for the complex interplay between vectors, pathogens and environmental factors to accurately assess the potential of vector-borne diseases to emerge. PMID:25122228

  12. Identification and genetic characterization of new bovine viral diarrhea virus genotype 2 strains in pigs isolated in China.

    PubMed

    Tao, Jie; Wang, Yin; Wang, Juan; Wang, Jian-ye; Zhu, Guo-qiang

    2013-02-01

    Classical swine fever (CSF)-like symptoms in pigs regarded as free from CSF has been reported previously. From sick pigs with CSF-like symptoms, and who had been inoculated with the hog cholera vaccine, samples were collected and subjected to RT-PCR using specific primers. Twelve bovine viral diarrhea virus 2 (BVDV-2) strains were screened and isolated. Homology comparison showed that the E2 genes of the twelve isolates were highly conserved. The genome of the one of the BVDV-2 isolates (named as SH-28) from the sick pigs, which showed a noncytopathic effect in MDBK cell cultures and strong reactivity with monoclonal antibody (MAb) Bz-53 raised against BVDV-2, was sequenced. The genome of SH-28 comprises 12,279 nucleotides and contains a large open reading frame beginning at nucleotide 386 and ending at nucleotide 12,073. Genomic comparison and phylogenetic analyzes showed that SH-28 fall into BVDV-2 subtype and was most similar to XJ-04 (nucleotide and amino acid homologies were 89.9-93.8 % and 91.1-96.9 %, respectively), but was genetically divergent from ZM-95 (pig BVDV-1). PMID:23085884

  13. Rapid methodology for antigenic profiling of FMDV field strains and for the control of identity, purity and viral integrity in commercial virus vaccines using monoclonal antibodies.

    PubMed

    Seki, Cristina; Robiolo, Blanca; Periolo, Osvaldo; Iglesias, Marcela; D'Antuono, Alejandra; Maradei, Eduardo; Barros, Virginia; La Torre, José; Mattion, Nora

    2009-01-13

    Monoclonal antibodies (MAbs) developed against different foot-and-mouth disease virus (FMDV) vaccine strains were extensively used to study any possible antigenic variations during vaccine production in Argentine facilities. Additionally, a typing ELISA using strain specific MAbs was developed to detect potential cross contaminations among FMDV strains in master and working seeds with high specificity and sensitivity and to confirm strains identity in formulated vaccines. This assay was carried out for the South American strains currently in use in production facilities in Argentina (A24/Cruzeiro, A/Argentina/01, O1/Campos and C3/Indaial) and for the strain O/Taiwan, produced only for export to Asia. These non-cross reactive MAbs were also used to analyze the integrity of viral particles belonging to each one of the individual strains, following isolation of 140S virions by means of sucrose density gradients from the aqueous phase of commercial polyvalent vaccines. Antigenic profiles were defined for FMDV reference strains using panels of MAbs, and a coefficient of correlation of reactivity with these panels was calculated to establish consistent identity upon serial passages of master and production seeds. A comparison of vaccine and field strain antigenic profiles performed using coefficients of correlation allowed the rapid identification of two main groups of serotype A viruses collected during the last FMD epidemic in Argentina, whose reactivity matched closely to A/Argentina/2000 and A/Argentina/2001 strains. PMID:18774662

  14. The Modes of Evolutionary Emergence of Primal and Late Pandemic Influenza Virus Strains from Viral Reservoir in Animals: An Interdisciplinary Analysis

    PubMed Central

    Shoham, Dany

    2011-01-01

    Based on a wealth of recent findings, in conjunction with earliest chronologies pertaining to evolutionary emergences of ancestral RNA viruses, ducks, Influenzavirus A (assumingly within ducks), and hominids, as well as to the initial domestication of mallard duck (Anas platyrhynchos), jungle fowl (Gallus gallus), wild turkey (Meleagris gallopavo), wild boar (Sus scrofa), and wild horse (Equus ferus), presumed genesis modes of primordial pandemic influenza strains have multidisciplinarily been configured. The virological fundamentality of domestication and farming of those various avian and mammalian species has thereby been demonstrated and broadly elucidated, within distinctive coevolutionary paradigms. The mentioned viral genesis modes were then analyzed, compatibly with common denominators and flexibility that mark the geographic profile of the last 18 pandemic strains, which reputedly emerged since 1510, the antigenic profile of the last 10 pandemic strains since 1847, and the genomic profile of the last 5 pandemic strains since 1918, until present. Related ecophylogenetic and biogeographic aspects have been enlightened, alongside with the crucial role of spatial virus gene dissemination by avian hosts. A fairly coherent picture of primary and late evolutionary and genomic courses of pandemic strains has thus been attained, tentatively. Specific patterns underlying complexes prone to generate past and future pandemic strains from viral reservoir in animals are consequentially derived. PMID:23074663

  15. The modes of evolutionary emergence of primal and late pandemic influenza virus strains from viral reservoir in animals: an interdisciplinary analysis.

    PubMed

    Shoham, Dany

    2011-01-01

    Based on a wealth of recent findings, in conjunction with earliest chronologies pertaining to evolutionary emergences of ancestral RNA viruses, ducks, Influenzavirus A (assumingly within ducks), and hominids, as well as to the initial domestication of mallard duck (Anas platyrhynchos), jungle fowl (Gallus gallus), wild turkey (Meleagris gallopavo), wild boar (Sus scrofa), and wild horse (Equus ferus), presumed genesis modes of primordial pandemic influenza strains have multidisciplinarily been configured. The virological fundamentality of domestication and farming of those various avian and mammalian species has thereby been demonstrated and broadly elucidated, within distinctive coevolutionary paradigms. The mentioned viral genesis modes were then analyzed, compatibly with common denominators and flexibility that mark the geographic profile of the last 18 pandemic strains, which reputedly emerged since 1510, the antigenic profile of the last 10 pandemic strains since 1847, and the genomic profile of the last 5 pandemic strains since 1918, until present. Related ecophylogenetic and biogeographic aspects have been enlightened, alongside with the crucial role of spatial virus gene dissemination by avian hosts. A fairly coherent picture of primary and late evolutionary and genomic courses of pandemic strains has thus been attained, tentatively. Specific patterns underlying complexes prone to generate past and future pandemic strains from viral reservoir in animals are consequentially derived. PMID:23074663

  16. Chest neoplasms with infectious etiologies

    PubMed Central

    Restrepo, Carlos S; Chen, Melissa M; Martinez-Jimenez, Santiago; Carrillo, Jorge; Restrepo, Catalina

    2011-01-01

    A wide spectrum of thoracic tumors have known or suspected viral etiologies. Oncogenic viruses can be classified by the type of genomic material they contain. Neoplastic conditions found to have viral etiologies include post-transplant lymphoproliferative disease, lymphoid granulomatosis, Kaposi’s sarcoma, Castleman’s disease, recurrent respiratory papillomatosis, lung cancer, malignant mesothelioma, leukemia and lymphomas. Viruses involved in these conditions include Epstein-Barr virus, human herpes virus 8, human papillomavirus, Simian virus 40, human immunodeficiency virus, and Human T-lymphotropic virus. Imaging findings, epidemiology and mechanism of transmission for these diseases are reviewed in detail to gain a more thorough appreciation of disease pathophysiology for the chest radiologist. PMID:22224176

  17. Interferon therapy in chronic hepatitis C virus: evidence of different outcome with respect to different viral strains.

    PubMed

    Pozzato, G; Moretti, M; Crocé, L S; Sasso, F; Kaneko, S; Unoura, M; Kobayashi, K; Crovatto, M; Santini, G; Tiribelli, C

    1995-04-01

    The aim of the study was to assess the role of different viral strains of hepatitis C virus (HCV) in determining the outcome of the alpha-interferon (IFN) therapy. Fifty-seven patients (34 from Italy and 23 from Japan) with HCV-positive liver disease were enrolled in the study. The NS4 region of HCV was amplified in sera by "nested" polymerase chain reaction (PCR) using a primer pair synthesized according to the sequence of JK-1. The NS4 region was positive in 14 (41%) Italian and in 13 (56%) Japanese patients. In positive patients the sequence of the NS4 region was also obtained. Subsequently, HCV genotype was determined in all patients by PCR amplification of the core region. All patients received recombinant alpha 2a-interferon (IFN), 6 million units 3 times a week for 1 month followed by 3 million units 3 times a week for 5 months. The patients were followed for 1 year after the end of treatment. At the end of the follow-up, 17 (30%) had sustained normal levels of serum alanine aminotransferase (ALT). The outcome of treatment was not correlated with race, age, sex, histology, and pretreatment ALT level, but was significantly (P < 0.00001) associated with the presence of both the NS4-JK-1 region and HCV type II. Among the 27 NS4-positive patients, only 1 patient (3.7%) achieved a complete response, whereas the remaining 26 patients (95.3%) either were non-responders or relapsed after IFN was discontinued.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7666045

  18. Construction of a subgenomic CV-B3 replicon expressing emerald green fluorescent protein to assess viral replication of a cardiotropic enterovirus strain in cultured human cells.

    PubMed

    Wehbe, Michel; Huguenin, Antoine; Leveque, Nicolas; Semler, Bert L; Hamze, Monzer; Andreoletti, Laurent; Bouin, Alexis

    2016-04-01

    Coxsackieviruses B (CV-B) (Picornaviridae) are a common infectious cause of acute myocarditis in children and young adults, a disease, which is a precursor to 10-20% of chronic myocarditis and dilated cardiomyopathy (DCM) cases. The mechanisms involved in the disease progression from acute to chronic myocarditis phase and toward the DCM clinical stage are not fully understood but are influenced by both viral and host factors. Subgenomic replicons of CV-B can be used to assess viral replication mechanisms in human cardiac cells and evaluate the effects of potential antiviral drugs on viral replication activities. Our objectives were to generate a reporter replicon from a cardiotropic prototype CV-B3/28 strain and to characterize its replication properties into human cardiac primary cells. To obtain this replicon, a cDNA plasmid containing the full CV-B3/28 genome flanked by a hammerhead ribozyme sequence and an MluI restriction site was generated and used as a platform for the insertion of sequences encoding emerald green fluorescent protein (EmGFP) in place of those encoding VP3. In vitro transcribed RNA from this plasmid was transfected into HeLa cells and human primary cardiac cells and was able to produce EmGFP and VP1-containing polypeptides. Moreover, non-structural protein biological activity was assessed by the specific cleavage of eIF4G1 by viral 2A(pro). Viral RNA replication was indirectly demonstrated by inhibition assays, fluoxetine was added to cell culture and prevented the EmGFP synthesis. Our results indicated that the EmGFP CV-B3 replicon was able to replicate and translate as well as the CV-B3/28 prototype strain. Our EmGFP CV-B3 replicon will be a valuable tool to readily investigate CV-B3 replication activities in human target cell models. PMID:26800776

  19. Cold-Adapted Viral Attenuation (CAVA): Highly Temperature Sensitive Polioviruses as Novel Vaccine Strains for a Next Generation Inactivated Poliovirus Vaccine

    PubMed Central

    Sanders, Barbara P.; de los Rios Oakes, Isabel; van Hoek, Vladimir; Bockstal, Viki; Kamphuis, Tobias; Uil, Taco G.; Song, Yutong; Cooper, Gillian; Crawt, Laura E.; Martín, Javier; Zahn, Roland; Lewis, John; Wimmer, Eckard; Custers, Jerome H. H. V.; Schuitemaker, Hanneke; Cello, Jeronimo; Edo-Matas, Diana

    2016-01-01

    The poliovirus vaccine field is moving towards novel vaccination strategies. Withdrawal of the Oral Poliovirus Vaccine and implementation of the conventional Inactivated Poliovirus Vaccine (cIPV) is imminent. Moreover, replacement of the virulent poliovirus strains currently used for cIPV with attenuated strains is preferred. We generated Cold-Adapted Viral Attenuation (CAVA) poliovirus strains by serial passage at low temperature and subsequent genetic engineering, which contain the capsid sequences of cIPV strains combined with a set of mutations identified during cold-adaptation. These viruses displayed a highly temperature sensitive phenotype with no signs of productive infection at 37°C as visualized by electron microscopy. Furthermore, decreases in infectious titers, viral RNA, and protein levels were measured during infection at 37°C, suggesting a block in the viral replication cycle at RNA replication, protein translation, or earlier. However, at 30°C, they could be propagated to high titers (9.4–9.9 Log10TCID50/ml) on the PER.C6 cell culture platform. We identified 14 mutations in the IRES and non-structural regions, which in combination induced the temperature sensitive phenotype, also when transferred to the genomes of other wild-type and attenuated polioviruses. The temperature sensitivity translated to complete absence of neurovirulence in CD155 transgenic mice. Attenuation was also confirmed after extended in vitro passage at small scale using conditions (MOI, cell density, temperature) anticipated for vaccine production. The inability of CAVA strains to replicate at 37°C makes reversion to a neurovirulent phenotype in vivo highly unlikely, therefore, these strains can be considered safe for the manufacture of IPV. The CAVA strains were immunogenic in the Wistar rat potency model for cIPV, inducing high neutralizing antibody titers in a dose-dependent manner in response to D-antigen doses used for cIPV. In combination with the highly productive

  20. Cold-Adapted Viral Attenuation (CAVA): Highly Temperature Sensitive Polioviruses as Novel Vaccine Strains for a Next Generation Inactivated Poliovirus Vaccine.

    PubMed

    Sanders, Barbara P; de Los Rios Oakes, Isabel; van Hoek, Vladimir; Bockstal, Viki; Kamphuis, Tobias; Uil, Taco G; Song, Yutong; Cooper, Gillian; Crawt, Laura E; Martín, Javier; Zahn, Roland; Lewis, John; Wimmer, Eckard; Custers, Jerome H H V; Schuitemaker, Hanneke; Cello, Jeronimo; Edo-Matas, Diana

    2016-03-01

    The poliovirus vaccine field is moving towards novel vaccination strategies. Withdrawal of the Oral Poliovirus Vaccine and implementation of the conventional Inactivated Poliovirus Vaccine (cIPV) is imminent. Moreover, replacement of the virulent poliovirus strains currently used for cIPV with attenuated strains is preferred. We generated Cold-Adapted Viral Attenuation (CAVA) poliovirus strains by serial passage at low temperature and subsequent genetic engineering, which contain the capsid sequences of cIPV strains combined with a set of mutations identified during cold-adaptation. These viruses displayed a highly temperature sensitive phenotype with no signs of productive infection at 37°C as visualized by electron microscopy. Furthermore, decreases in infectious titers, viral RNA, and protein levels were measured during infection at 37°C, suggesting a block in the viral replication cycle at RNA replication, protein translation, or earlier. However, at 30°C, they could be propagated to high titers (9.4-9.9 Log10TCID50/ml) on the PER.C6 cell culture platform. We identified 14 mutations in the IRES and non-structural regions, which in combination induced the temperature sensitive phenotype, also when transferred to the genomes of other wild-type and attenuated polioviruses. The temperature sensitivity translated to complete absence of neurovirulence in CD155 transgenic mice. Attenuation was also confirmed after extended in vitro passage at small scale using conditions (MOI, cell density, temperature) anticipated for vaccine production. The inability of CAVA strains to replicate at 37°C makes reversion to a neurovirulent phenotype in vivo highly unlikely, therefore, these strains can be considered safe for the manufacture of IPV. The CAVA strains were immunogenic in the Wistar rat potency model for cIPV, inducing high neutralizing antibody titers in a dose-dependent manner in response to D-antigen doses used for cIPV. In combination with the highly productive

  1. Viral forensic genomics reveals the relatedness of classic herpes simplex virus strains KOS, KOS63, and KOS79.

    PubMed

    Bowen, Christopher D; Renner, Daniel W; Shreve, Jacob T; Tafuri, Yolanda; Payne, Kimberly M; Dix, Richard D; Kinchington, Paul R; Gatherer, Derek; Szpara, Moriah L

    2016-05-01

    Herpes simplex virus 1 (HSV-1) is a widespread global pathogen, of which the strain KOS is one of the most extensively studied. Previous sequence studies revealed that KOS does not cluster with other strains of North American geographic origin, but instead clustered with Asian strains. We sequenced a historical isolate of the original KOS strain, called KOS63, along with a separately isolated strain attributed to the same source individual, termed KOS79. Genomic analyses revealed that KOS63 closely resembled other recently sequenced isolates of KOS and was of Asian origin, but that KOS79 was a genetically unrelated strain that clustered in genetic distance analyses with HSV-1 strains of North American/European origin. These data suggest that the human source of KOS63 and KOS79 could have been infected with two genetically unrelated strains of disparate geographic origins. A PCR RFLP test was developed for rapid identification of these strains. PMID:26950505

  2. A reverse genetics system for the Great Lakes strain of viral hemorrhagic septicemia virus: the NV gene is required for pathogenicity

    USGS Publications Warehouse

    Ammayappan, Arun; Kurath, Gael; Thompson, Tarin M.; Vakharia, Vikram N.

    2011-01-01

    Viral hemorrhagic septicemia virus (VHSV), belonging to the genus Novirhabdovirus in the family of Rhabdoviridae, causes a highly contagious disease of fresh and saltwater fish worldwide. Recently, a novel genotype of VHSV, designated IVb, has invaded the Great Lakes in North America, causing large-scale epidemics in wild fish. An efficient reverse genetics system was developed to generate a recombinant VHSV of genotype IVb from cloned cDNA. The recombinant VHSV (rVHSV) was comparable to the parental wild-type strain both in vitro and in vivo, causing high mortality in yellow perch (Perca flavescens). A modified recombinant VHSV was generated in which the NV gene was substituted with an enhanced green fluorescent protein gene (rVHSV-ΔNV-EGFP), and another recombinant was made by inserting the EGFP gene into the full-length viral clone between the P and M genes (rVHSV-EGFP). The in vitro replication kinetics of rVHSV-EGFP was similar to rVHSV; however, the rVHSV-ΔNV-EGFP grew 2 logs lower. In yellow perch challenges, wtVHSV and rVHSV induced 82-100% cumulative per cent mortality (CPM), respectively, whereas rVHSV-EGFP produced 62% CPM and rVHSV-ΔNV-EGFP caused only 15% CPM. No reversion of mutation was detected in the recovered viruses and the recombinant viruses stably maintained the foreign gene after several passages. These results indicate that the NV gene of VHSV is not essential for viral replication in vitro and in vivo, but it plays an important role in viral replication efficiency and pathogenicity. This system will facilitate studies of VHSV replication, virulence, and production of viral vectored vaccines.

  3. [Antigenic determination of human anti-rabies vaccine against viral street strains common in the wild animal population in Poland].

    PubMed

    Seroka, D

    1994-01-01

    The aim of the study was to compare the antigen properties of a vaccine strain with street strains isolated from various animal hosts throughout the country. Investigation was carried out using monoclonal antibodies against NC protein. Also, two tests were carried out: the modified NIH test for potency and the neutralization test using the sera of people vaccinated against rabies (PM vaccine strain). The investigated street strains were used in both tests as the challenge viruses. A suspension of these strains diluted five times made it possible to avoid extreme values of animal survival (0% or 100%) what, consequently, made calculation of the LD50 value easier. A different rabies virus serotype (EBLI virus) in the population of insectivore bats Eptesicus serotinus and antigen variants within the first serotype, having common epitopes with strains of the vaccine virus SAD B19 and the polar rabies virus, were found to be present throughout the country. The concentrated and purified vaccine containing the PM virus did not protect mice against infection with strains of viruses isolated from bats (protection index 10 and lower). For the remaining strains, depending on the animal source of their isolation, the protection index ranged from 10 to 1000 and higher. The properties neutralizing a dose of 5 i.u./ml of serum from the subject inoculated with the vaccine containing the PM strain were similar for all the investigated strains; 0,5 i.u./ml did not neutralize the strain isolated from a racoon dog. PMID:7541494

  4. Maintenance of picobirnavirus (PBV) infection in an adult orangutan (Pongo pygmaeus) and genetic diversity of excreted viral strains during a three-year period.

    PubMed

    Masachessi, Gisela; Ganesh, Balasubramanian; Martinez, Laura C; Giordano, Miguel O; Barril, Patricia A; Isa, Maria B; Paván, Giorgio V; Mateos, Carlos A; Nates, Silvia V

    2015-01-01

    The present work provide data about the maintenance of picobirnavirus (PBV) infection during adulthood in a mammalian host. For this purpose PBV infection was studied in an adult orangutan (Pongo pygmaeus) by PAGE/SS, RT-PCR and nucleotide sequencing. PBV infection in the animal was asymptomatic and was characterized by interspaced silent and high/ low active viral excretion periods. The PBV strains excreted by the studied individual were identified as genogroup I and revealed a nucleotide identity among them of 64-81%. The results obtained allowed to arrive to a deeper understanding of the natural history of PBV infection, which seems to be characterized by new-born, juvenile and adult asymptomatic hosts which persistently excrete closely related strains in their feces. Consequently, picobirnaviruses could be considered frequent inhabitants of the gastrointestinal tract, leaving the question open about the molecular mechanisms governing persistent and asymptomatic coexistence within the host and the potential host suitability to maintain this relationship. PMID:25435283

  5. The effect of bovine viral diarrhea virus (BVDV) strains on bovine monocyte-derived dendritic cells (Mo-DC) phenotype and capacity to produce BVDV

    PubMed Central

    2014-01-01

    Background Dendritic cells (DC) are important antigen presentation cells that monitor, process, and present antigen to T cells. Viruses that infect DC can have a devastating impact on the immune system. In this study, the ability of bovine viral diarrhea virus (BVDV) to replicate and produce infectious virus in monocyte-derived dendritic cells (Mo-DC) and monocytes was studied. The study also examined the effect of BVDV infection on Mo-DC expression of cell surface markers, including MHCI, MHCII, and CD86, which are critical for DC function in immune response. Methods Peripheral blood mononuclear cells (PBMCs) were isolated from bovine blood through gradient centrifugation. The adherent monocytes were isolated from PBMCs and differentiated into Mo-DC using bovine recombinant interleukin-4 (IL-4) and granulocyte-macrophage colony-stimulating factor (GMCSF). To determine the effect of BVDV on Mo-DC, four strains of BVDV were used including the severe acute non-cytopathic (ncp) BVDV2a-1373; moderate acute ncp BVDV2a 28508-5; and a homologous virus pair [i.e., cytopathic (cp) BVDV1b TGAC and ncp BVDV1b TGAN]. The Cooper strain of bovine herpesvirus 1 (BHV1) was used as the control virus. Mo-DC were infected with one of the BVDV strains or BHV-1 and were subsequently examined for virus replication, virus production, and the effect on MHCI, MHCII, and CD86 expression. Results The ability of monocytes to produce infectious virus reduced as monocytes differentiated to Mo-DC, and was completely lost at 120 hours of maturation. Interestingly, viral RNA increased throughout the course of infection in Mo-DC, and the viral non-structural (NS5A) and envelope (E2) proteins were expressed. The ncp strains of BVDV down-regulated while cp strain up-regulated the expression of the MHCI, MHCII, and CD86 on Mo-DC. Conclusions The study revealed that the ability of Mo-DC to produce infectious virus was reduced with its differentiation from monocytes to Mo-DC. The inability to produce

  6. Unraveling the etiology of North American grapevine yellows (NAGY): multilocus genotyping and structural analysis of secY proteins distinguish NAGYIII phytoplasma strains from strains causing X-disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    North American grapevine yellows (NAGY) disease has sometimes been ascribed to infection of Vitis vinifera L. by X-disease phytoplasma, but the accuracy of this attribution has remained open to question. In the present study of NAGY etiology, the disease was discovered in Maryland, Pennsylvania, Oh...

  7. Early Age at Time of Primary Epstein–Barr Virus Infection Results in Poorly Controlled Viral Infection in Infants From Western Kenya: Clues to the Etiology of Endemic Burkitt Lymphoma

    PubMed Central

    Piriou, Erwan; Asito, Amolo S.; Sumba, Peter O.; Fiore, Nancy; Middeldorp, Jaap M.; Moormann, Ann M.; Ploutz-Snyder, Robert

    2012-01-01

    (See the editorial commentary by Bagni and Whitby, on pages 873–4.) Background. Infection with Epstein–Barr virus (EBV) early in life and repeated malaria exposure have been proposed as risk factors for endemic Burkitt lymphoma (eBL). Methods. Infants were enrolled from 2 rural sites in Kenya: the Kisumu District, where malaria transmission is holoendemic and risk for eBL is high, and the Nandi District, where malaria transmission is limited and the risk for eBL is low. Blood samples were taken from infants through 2 years of age to measure EBV viral load, EBV antibodies, and malaria parasitemia. Results. We observed a significantly younger age at time of primary EBV infection in children from Kisumu compared with children from Nandi (mean age, 7.28 months [±0.33 SEM] in Kisumu vs 8.39 months [±0.26 SEM] in Nandi), with 35.3% of children in Kisumu infected before 6 months of age. To analyze how different predictors affected EBV viral load over time, we performed multilevel mixed modeling. This modeling revealed that residence in Kisumu and younger age at first EBV infection were significant predictors for having a higher EBV viral load throughout the period of observation. Conclusions. Children from a region at high risk for eBL were infected very early in life with EBV, resulting in higher viral loads throughout infancy. PMID:22301635

  8. A nationwide database linking information on the hosts with sequence data of their virus strains: A useful tool for the eradication of bovine viral diarrhea (BVD) in Switzerland.

    PubMed

    Stalder, Hanspeter; Hug, Corinne; Zanoni, Reto; Vogt, Hans-Rudolf; Peterhans, Ernst; Schweizer, Matthias; Bachofen, Claudia

    2016-06-15

    Pestiviruses infect a wide variety of animals of the order Artiodactyla, with bovine viral diarrhea virus (BVDV) being an economically important pathogen of livestock globally. BVDV is maintained in the cattle population by infecting fetuses early in gestation and, thus, by generating persistently infected (PI) animals that efficiently transmit the virus throughout their lifetime. In 2008, Switzerland started a national control campaign with the aim to eradicate BVDV from all bovines in the country by searching for and eliminating every PI cattle. Different from previous eradication programs, all animals of the entire population were tested for virus within one year, followed by testing each newborn calf in the subsequent four years. Overall, 3,855,814 animals were tested from 2008 through 2011, 20,553 of which returned an initial BVDV-positive result. We were able to obtain samples from at least 36% of all initially positive tested animals. We sequenced the 5' untranslated region (UTR) of more than 7400 pestiviral strains and compiled the sequence data in a database together with an array of information on the PI animals, among others, the location of the farm in which they were born, their dams, and the locations where the animals had lived. To our knowledge, this is the largest database combining viral sequences with animal data of an endemic viral disease. Using unique identification tags, the different datasets within the database were connected to run diverse molecular epidemiological analyses. The large sets of animal and sequence data made it possible to run analyses in both directions, i.e., starting from a likely epidemiological link, or starting from related sequences. We present the results of three epidemiological investigations in detail and a compilation of 122 individual investigations that show the usefulness of such a database in a country-wide BVD eradication program. PMID:26403669

  9. Antigenic differences among NDV strains of different genotypes used in vaccine formulation affects viral shedding after a virulent challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Strains of Newcastle disease virus (NDV) can be separated into genotypes based on genome differences even though they are antigenically considered to be of a single serotype. It is widely recognized that an efficacious Newcastle disease (ND) vaccine made with any NDV does induce protection against ...

  10. Viral Hepatitis

    MedlinePlus

    ... Public Home » For Veterans and the Public Viral Hepatitis Menu Menu Viral Hepatitis Viral Hepatitis Home For ... the Public Veterans and Public Home How is Hepatitis C Treated? Find the facts about the newest ...

  11. Viral Parkinsonism

    PubMed Central

    Jang, Haeman; Boltz, David A.; Webster, Robert G.; Smeyne, Richard Jay

    2015-01-01

    Parkinson's disease is a debilitating neurological disorder characterized that affects 1-2% of the adult population over 55 years of age. For the vast majority of cases, the etiology of this disorder is unknown, although it is generally accepted that there is a genetic susceptibility to any number of environmental agents. One such agent may be viruses. It has been shown that numerous viruses can enter the nervous system, i.e. they are neurotropic, and induce a number of encephalopathies. One of the secondary consequences of these encephalopathies can be parkinsonism, that is both transient as well as permanent. One of the most highlighted and controversial cases of viral parkinsonism is that which followed the 1918 influenza outbreak and the subsequent induction of von Economo's encephalopathy. In this review, we discuss the neurological sequelae of infection by influenza virus as well as that of other viruses known to induce parkinsonism including Coxsackie, Japanese encephalitis B, St. Louis, West Nile and HIV viruses. PMID:18760350

  12. PhyloFlu, a DNA Microarray for Determining the Phylogenetic Origin of Influenza A Virus Gene Segments and the Genomic Fingerprint of Viral Strains

    PubMed Central

    Paulin, Luis F.; Soto-Del Río, María de los D.; Sánchez, Iván; Hernández, Jesús; Gutiérrez-Ríos, Rosa M.; López-Martínez, Irma; Wong-Chew, Rosa M.; Parissi-Crivelli, Aurora; Isa, P.; López, Susana

    2014-01-01

    Recent evidence suggests that most influenza A virus gene segments can contribute to the pathogenicity of the virus. In this regard, the hemagglutinin (HA) subtype of the circulating strains has been closely surveyed, but the reassortment of internal gene segments is usually not monitored as a potential source of an increased pathogenicity. In this work, an oligonucleotide DNA microarray (PhyloFlu) designed to determine the phylogenetic origins of the eight segments of the influenza virus genome was constructed and validated. Clades were defined for each segment and also for the 16 HA and 9 neuraminidase (NA) subtypes. Viral genetic material was amplified by reverse transcription-PCR (RT-PCR) with primers specific to the conserved 5′ and 3′ ends of the influenza A virus genes, followed by PCR amplification with random primers and Cy3 labeling. The microarray unambiguously determined the clades for all eight influenza virus genes in 74% (28/38) of the samples. The microarray was validated with reference strains from different animal origins, as well as from human, swine, and avian viruses from field or clinical samples. In most cases, the phylogenetic clade of each segment defined its animal host of origin. The genomic fingerprint deduced by the combined information of the individual clades allowed for the determination of the time and place that strains with the same genomic pattern were previously reported. PhyloFlu is useful for characterizing and surveying the genetic diversity and variation of animal viruses circulating in different environmental niches and for obtaining a more detailed surveillance and follow up of reassortant events that can potentially modify virus pathogenicity. PMID:24353006

  13. The North American strain of viral hemorrhagic septicemia virus is highly pathogenic for laboratory-reared Pacific herring (Clupea pallasi)

    USGS Publications Warehouse

    Kocan, R.; Bradley, M.; Elder, N.; Meyers, T.; Batts, W.; Winton, J.

    1997-01-01

    Specific-pathogen-free Pacific herring Clupea pallasi were reared in the laboratory from eggs and then challenged at 5, 9, and 13 months of age by waterborne exposure to low (101.5–2.5 plaque-forming units [PFU] per milliliter), medium (103.5–4.5 PFU/mL), or high (105.5–6.5 PFU/mL) levels of a North American isolate of viral hemorrhagic septicemia virus (VHSV). The fish were extremely susceptible to the virus, showing clinical disease, mortality approaching 100%, and only a limited increase in resistance with age. Mortality began 4–6 d after exposure and peaked at approximately day 7 in fish exposed to high levels of virus. Whereas the mean time to death showed a significant dose response (P < 0.001), the percent mortality and virus titers in dead fish were generally high in all groups regardless of initial challenge dose. External signs of disease were usually limited to 1–2-mm hemorrhagic areas on the lower jaw and isthmus and around the eye, but 2 of 130 infected fish exhibited extensive cutaneous hemorrhaging. Histopathologic examination of tissues from moribund fish sampled at 2–8 d after exposure revealed multifocal coagulative necrosis of hepatocytes, diffuse necrosis of interstitial hematopoietic tissues in the kidney, diffuse necrosis of the spleen, epidermis, and subcutis, and occasional necrosis of pancreatic acinar cells. Virus titers in tissues of experimentally infected herring were first detected 48 h after exposure and peaked 6-8 d after exposure at 107.7 PFU/g. Fish began shedding virus at 48 h after exposure with titers in the flow-through aquaria reaching 102.5 PFU/mL at 4–5 d after exposure, just before peak mortality. When the water flow was turned off for 3 h, titers in the water rose to 103.5 PFU/mL, and the amount of virus shed by infected fish (on average, greater than 106.5 PFU/h per fish) appeared sufficient to sustain a natural epizootic among schooling herring. Taken together, these data suggest that VHSV could be a

  14. Genetic characterization of bovine viral diarrhea virus strains in Beijing, China and innate immune responses of peripheral blood mononuclear cells in persistently infected dairy cattle

    PubMed Central

    Weng, Xiao Gang; Song, Quan Jiang; Wu, Qiong; Liu, Ming Chao; Wang, Meng Ling

    2015-01-01

    To acquire epidemiological data on the bovine viral diarrhea virus (BVDV) and identify cattle persistently infected (PI) with this virus, 4,327 samples from Holstein dairy cows were screened over a four-year period in Beijing, China. Eighteen BVD viruses were isolated, 12 from PI cattle. Based on genetic analysis of their 5'-untranslated region (5'-UTR), the 18 isolates were assigned to subgenotype BVDV-1m, 1a, 1d, 1q, and 1b. To investigate the innate immune responses in the peripheral-blood mononuclear cells of PI cattle, the expression of Toll-like receptors (TLRs), RIG-I-like receptors, interferon-α (IFN-α), IFN-β, myxovirus (influenza virus) resistance 1 (MX1), and interferon stimulatory gene 15 (ISG15) was assessed by qPCR. When compared with healthy cattle, the expression of TLR-7, IFN-α, and IFN-β mRNA was downregulated, but the expression of MX1 and ISG-15 mRNA was upregulated in PI cattle. Immunoblotting analysis revealed that the expression of interferon regulatory factor 3 (IRF-3) and IRF-7 was lower in PI cattle than in healthy cattle. Thus, BVDV-1m and 1a are the predominant subgenotypes in the Beijing region, and the strains are highly divergent. Our findings also suggest that the TLR-7/IRF-7 signaling pathway plays a role in evasion of host restriction by BVDV. PMID:26119170

  15. Survival of the North American strain of viral hemorrhagic septicemia virus (VHSV) in filtered seawater and seawater containing ovarian fluid, crude oil and serum-enriched culture medium

    USGS Publications Warehouse

    Kocan, R.M.; Hershberger, P.K.; Elder, N.E.

    2001-01-01

     The North American strain of viral hemorrhagic septicemia virus (NA-VHSV) could be recovered for up to 40 h in natural filtered seawater (27 ppt) with a 50% loss of infectivity after approximately 10 h at 15°C. Addition of 10 ppb North Slope crude oil to the seawater had no effect on virus survival. However, when various concentrations of teleost ovarian fluid were added to seawater, virus could be recovered after 72 h at 0.01% ovarian fluid and after 96 h at 1.0%. When cell culture medium supplemented with 10% fetal bovine serum was added to the seawater, 100% of the virus could be recovered for the first 15 d and 60% of the virus remained after 36 d. These findings quantify NA-VHSV infectivity in natural seawater and demonstrate that ovarian fluid, which occurs naturally during spawning events, significantly prolongs the survival and infectivity of the virus. The extended stabilization of virus in culture medium supplemented with serum allows for low titer field samples to be collected and transported in an unfrozen state without significant loss of virus titer.

  16. Paraconsistents artificial neural networks applied to the study of mutational patterns of the F subtype of the viral strains of HIV-1 to antiretroviral therapy.

    PubMed

    dos Santos, Paulo C C; Lopes, Helder F S; Alcalde, Rosana; Gonsalez, Cláudio R; Abe, Jair M; Lopez, Luis F

    2016-03-01

    The high variability of HIV-1 as well as the lack of efficient repair mechanisms during the stages of viral replication, contribute to the rapid emergence of HIV-1 strains resistant to antiretroviral drugs. The selective pressure exerted by the drug leads to fixation of mutations capable of imparting varying degrees of resistance. The presence of these mutations is one of the most important factors in the failure of therapeutic response to medications. Thus, it is of critical to understand the resistance patterns and mechanisms associated with them, allowing the choice of an appropriate therapeutic scheme, which considers the frequency, and other characteristics of mutations. Utilizing Paraconsistents Artificial Neural Networks, seated in Paraconsistent Annotated Logic Et which has the capability of measuring uncertainties and inconsistencies, we have achieved levels of agreement above 90% when compared to the methodology proposed with the current methodology used to classify HIV-1 subtypes. The results demonstrate that Paraconsistents Artificial Neural Networks can serve as a promising tool of analysis. PMID:26959313

  17. Viral Phylodynamics

    PubMed Central

    Volz, Erik M.; Koelle, Katia; Bedford, Trevor

    2013-01-01

    Viral phylodynamics is defined as the study of how epidemiological, immunological, and evolutionary processes act and potentially interact to shape viral phylogenies. Since the coining of the term in 2004, research on viral phylodynamics has focused on transmission dynamics in an effort to shed light on how these dynamics impact viral genetic variation. Transmission dynamics can be considered at the level of cells within an infected host, individual hosts within a population, or entire populations of hosts. Many viruses, especially RNA viruses, rapidly accumulate genetic variation because of short generation times and high mutation rates. Patterns of viral genetic variation are therefore heavily influenced by how quickly transmission occurs and by which entities transmit to one another. Patterns of viral genetic variation will also be affected by selection acting on viral phenotypes. Although viruses can differ with respect to many phenotypes, phylodynamic studies have to date tended to focus on a limited number of viral phenotypes. These include virulence phenotypes, phenotypes associated with viral transmissibility, cell or tissue tropism phenotypes, and antigenic phenotypes that can facilitate escape from host immunity. Due to the impact that transmission dynamics and selection can have on viral genetic variation, viral phylogenies can therefore be used to investigate important epidemiological, immunological, and evolutionary processes, such as epidemic spread [2], spatio-temporal dynamics including metapopulation dynamics [3], zoonotic transmission, tissue tropism [4], and antigenic drift [5]. The quantitative investigation of these processes through the consideration of viral phylogenies is the central aim of viral phylodynamics. PMID:23555203

  18. Viral pneumonia

    MedlinePlus

    ... Names Pneumonia - viral; "Walking pneumonia" - viral Images Lungs Respiratory system References Lee FE, Treanor J. Viral infections. In: Mason RJ, VC Broaddus, Martin TR, et al, eds. Murray and Nadel’s Textbook of Respiratory Medicine . 5th ed. Philadelphia, PA: Saunders Elsevier; 2010: ...

  19. Zika virus: what do we know about the viral structure, mechanisms of transmission, and neurological outcomes?

    PubMed

    Silva, Lucia Regina Cangussu da; Souza, Adriano Miranda de

    2016-01-01

    The Zika virus epidemic that started in Brazil in 2014 has spread to >30 countries and territories in Latin America, leading to a rapid rise in the incidence of microcephalic newborns and adults with neurological complications. At the beginning of the outbreak, little was known about Zika virus morphology, genome structure, modes of transmission, and its potential to cause neurological malformations and disorders. With the advancement of basic science, discoveries of the mechanisms of strain variability, viral transfer to the fetus, and neurovirulence were published. These will certainly lead to the development of strategies to block vertical viral transmission, neuronal invasion, and pathogenesis in the near future. This paper reviews the current literature on Zika virus infections, with the aim of gaining a holistic insight into their etiology and pathogenesis. We discuss Zika virus history and epidemiology in Brazil, viral structure and taxonomy, old and newly identified transmission modes, and neurological consequences of infection. PMID:27384821

  20. Characteristics of Foot-and-Mouth Disease Viral Strains Circulating at the Wildlife/livestock Interface of the Great Limpopo Transfrontier Conservation Area.

    PubMed

    Jori, F; Caron, A; Thompson, P N; Dwarka, R; Foggin, C; de Garine-Wichatitsky, M; Hofmeyr, M; Van Heerden, J; Heath, L

    2016-02-01

    Foot-and-mouth disease (FMD) inflicts severe economic losses within infected countries and is arguably the most important trade-restricting livestock disease in the world. In southern Africa, infected African buffaloes (Syncerus caffer) are the major reservoir of the South African Territories (SAT) types of the virus. With the progressive expansion of transfrontier conservation areas (TFCAs), the risk of FMD outbreaks is expected to increase due to a higher probability of buffalo/livestock contacts. To investigate the dynamics of FMD within and around the Great Limpopo TFCA (GLTFCA), 5 herds of buffaloes were sampled in June 2010 to characterize circulating viruses in South Africa and Zimbabwe. Three SAT-2 and three SAT-3 viral strains were isolated in both countries, including one that was genetically linked with a recent SAT-2 outbreak in Mozambique in 2011. In addition, two groups of unvaccinated cattle (n = 192) were serologically monitored for 1 year at the wildlife/livestock interface of Gonarezhou National Park (GNP) in Zimbabwe between April 2009 and January 2010, using the liquid-phase blocking ELISA (LPBE) and a test for antibodies directed against non-structural proteins (NSP). Neither clinical signs nor vaccination of cattle were reported during the study, yet a high proportion of the monitored cattle showed antibody responses against SAT-3 and SAT-1. Antibodies against NSP were also detected in 10% of the monitored cattle. The results of this study suggest that cattle grazing in areas adjacent to the GLTFCA can be infected by buffalo or other infected livestock and that cattle trade movements can act as efficient disseminators of FMD viruses to areas several hundred kilometres from the virus source. Current methods of surveillance of FMD at the GLTFCA interface seem insufficient to control for FMD emergence and dissemination and require urgent reassessment and regional coordination. PMID:24739536

  1. Comparative susceptibility among three stocks of yellow perch, Perca flavescens (Mitchill), to viral haemorrhagic septicaemia virus strain IVb from the Great Lakes

    USGS Publications Warehouse

    Olson, W.; Emmenegger, E.; Glenn, J.; Winton, J.; Goetz, F.

    2013-01-01

    The Great Lakes strain of viral haemorrhagic septicaemia virus IVb (VHSV-IVb) is capable of infecting a wide number of naive species and has been associated with large fish kills in the Midwestern United States since its discovery in 2005. The yellow perch, Perca flavescens (Mitchill), a freshwater species commonly found throughout inland waters of the United States and prized for its high value in sport and commercial fisheries, is a species documented in several fish kills affiliated with VHS. In the present study, differences in survival after infection with VHSV IVb were observed among juvenile fish from three yellow perch broodstocks that were originally derived from distinct wild populations, suggesting innate differences in susceptibility due to genetic variance. While all three stocks were susceptible upon waterborne exposure to VHS virus infection, fish derived from the Midwest (Lake Winnebago, WI) showed significantly lower cumulative % survival compared with two perch stocks derived from the East Coast (Perquimans River, NC and Choptank River, MD) of the United States. However, despite differences in apparent susceptibility, clinical signs did not vary between stocks and included moderate-to-severe haemorrhages at the pelvic and pectoral fin bases and exophthalmia. After the 28-day challenge was complete, VHS virus was analysed in subsets of whole fish that had either survived or succumbed to the infection using both plaque assay and quantitative PCR methodologies. A direct correlation was identified between the two methods, suggesting the potential for both methods to be used to detect virus in a research setting.

  2. [Etiological factors of acute pancreatitis].

    PubMed

    Spicák, J

    2002-09-01

    Acute pancreatitis develops immediately after the causative impulse, while chronic pancreatitis develops after the long-term action of the noxious agent. A typical representative of acute pancreatitis is biliary pancreatitis, chronic pancreatitis develops in alcoholism and has a long latency. As alcoholic pancreatitis is manifested at first as a rule by a potent attack, it is classified in this stage as acute pancreatitis. The most frequent etiological factors in our civilization are thus cholelithiasis and alcoholism (both account for 20-50% in different studies). The assumed pathogenetic principles in acute biliary pancreatitis are the common canal of both efferent ducts above the obturated papilla, duodenopancreatic reflux and intrapancreatic hypertension. A detailed interpretation is however lacking. The pathogenesis of alcoholic pancreatitis is more complicated. Among others some part is played by changes in the calcium concentration and fusion of cellular membranes. Idiopathic pancreatitis occurs in up to 10%, part of the are due to undiagnosed alcoholism and cholelithiasis. Other etiologies are exceptional. Similarly as in cholelithiasis pancreatitis develops also during other pathological processes in the area of the papilla of Vater such as dysfunction of the sphincter of Oddi, ampulloma and juxtapapillary diverticulum, it is however usually mild. The incidence of postoperative pancreatitis is declining. Its lethality is 30% and the diagnosis is difficult. In the pathogenesis changes of the ion concentration are involved, hypoxia and mechanical disorders of the integrity of the gland. Pancreatitis develops in association with other infections--frequently in mumps, rarely in hepatitis, tuberculosis, typhoid and mycoses. Viral pancreatitis is usually mild. In parasitoses pancreatitis develops due to a block of the papilla Vateri. In hyperparathyroidism chronic pancreatitis is more likely to develop, recent data are lacking. As to dyslipoproteinaemias

  3. [Clinical syndrome of convulsive cough of adenoviral etiology in a children's collective].

    PubMed

    Grobnicu, M; Andreescu, V; Caffé, I; Măgureanu, E; Marion, M; Ivan, I; Botez, D; Cuteanu, I; Barbu, I

    1976-01-01

    Bacteriological, viral and serological investigators were carried out in a community with 100 prescholar children (Kindergarden), 34 of whom presented a clinical syndrome of whooping cough, in order to establish the bacteriologic or viral etiology of the syndrome. The etiologic role of organisms of the Bordetella, B. pertussis and B. parapertussis was invalidated by the bacteriologic and serological tests. Viral and serological tests, performed to demonstrate the participation of viral agents in the causation of this clinical syndrome, established an adenoviral diagnosis in 13 (43.3%) of the 30 children. Adenovirus type 6 was isolated and there was a significant increase in the titers of antibodies to adenoviruses. PMID:184515

  4. ANEUPLOIDY: ETIOLOGY AND MECHANISMS

    EPA Science Inventory

    The 'Symposium on Aneuploidy: Etiology and Mechanisms' was held from March 25-29, 1985. This Symposium developed as a consequence of the concern of the Environmental Protection Agency with the support of the National Institute of Environmental Health Sciences about human exposure...

  5. The Etiology of Giftedness

    ERIC Educational Resources Information Center

    Thompson, Lee Anne; Oehlert, Jeremy

    2010-01-01

    Many theories of giftedness either explicitly or implicitly acknowledge the role of genetic influences; yet, empirical work has not been able to establish the impact that genes have specifically on gifted behavior. In contrast, a great deal of research has been targeted at understanding the etiology of individual differences in general and…

  6. [Biological etiologies of transsexualism].

    PubMed

    Butty, Anne-Virginie; Bianchi-Demicheli, Francesco

    2016-03-16

    Transsexualism or gender dysphoria is a disorder of sexual identity of unknown etiology. At the biological level, one assumes atypical brain development during certain periods of its formation (genesis) notably during embryogenesis, as a result of altered hormonal influence and a particular genetic polymorphism. This article summarizes the research conducted to date in these three areas only, excluding psycho-social and environmental factors. PMID:27149713

  7. Viral meningitis.

    PubMed

    Chadwick, David R

    2005-01-01

    Viruses probably account for most cases of acute meningitis. Viral meningitis is often assumed to be a largely benign disease. For the commonest pathogens causing meningitis, enteroviruses, this is usually the case; however, for many of the other pathogens causing viral meningitis, and for common pathogens in the immunocompromised or infants, viral meningitis is frequently associated with substantial neurological complications and a significant mortality. Diagnostic methods for rapid and accurate identification of pathogens have improved over recent years, permitting more precise and earlier diagnoses. There have been fewer developments in therapies for viral meningitis, and there remain no effective therapies for most pathogens, emphasising the importance of prevention and early diagnosis. This review focuses on the presentation, diagnosis and management of viral meningitis and also covers the prevention of meningitis for pathogens where effective vaccines are available. PMID:16474042

  8. Viral infection, inflammation and schizophrenia

    PubMed Central

    Kneeland, Rachel E.; Fatemi, S. Hossein

    2012-01-01

    Schizophrenia is a severe neurodevelopmental disorder with genetic and environmental etiologies. Prenatal viral/bacterial infections and inflammation play major roles in the genesis of schizophrenia. In this review, we describe a viral model of schizophrenia tested in mice whereby the offspring of mice prenatally infected with influenza at E7, E9, E16, and E18 show significant gene, protein, and brain structural abnormalities postnatally. Similarly, we describe data on rodents exposed to bacterial infection or injected with a synthetic viral mimic (PolyI:C) also demonstrating brain structural and behavioral abnormalities. Moreover, human serologic data has been indispensible in supporting the viral theory of schizophrenia. Individuals born seropositive for bacterial and viral agents are at a significantly elevated risk of developing schizophrenia. While the specific mechanisms of prenatal viral/bacterial infections and brain disorder are unclear, recent findings suggest that the maternal inflammatory response may be associated with fetal brain injury. Preventive and therapeutic treatment options are also proposed. This review presents data related to epidemiology, human serology, and experimental animal models which support the viral model of schizophrenia. PMID:22349576

  9. ETIOLOGY OF OROYA FEVER

    PubMed Central

    Noguchi, Hideyo

    1928-01-01

    Through the cooperation of Dr. Sebastian Lorente, Director of the National Department of Public Health of Peru, nine strains of Bartonella bacilliformis have been isolated, by means of the semisolid leptospira medium, from nine of twelve specimens of blood withdrawn from cases of verruga and forwarded from Peru under conditions of refrigeration. The cultural titer of the blood specimens immediately after their arrival (2 weeks after withdrawal) varied from 1:10 to 1:100,000. Blood from the severe anemic type of the disease, in which there was no eruption, had the highest titer. Blood agar slants yielded irregular results, but some strains grew well on these media. Morphologically the strains differed very little in fresh preparations examined by dark-ground illumination. In stained preparations some strains appeared coarser, others finer than the average. Special staining indicated that the flagella were characteristically unipolar and varied in number from one to four, some strains showing distinctly more wavy and heavier flagella than others. Young cultures grown on the surface of horse blood agar for 3 to 6 days show individuals with fairly sharp contours, short rods, often varying in thickness toward one or both ends, being intermingled with smaller oval or coccoid elements. Some strains show a predominance of bacillary, some of coccobacillary forms. It is not known whether these features are inherent or are due to conditions of growth, which, though identical, may react differently upon different strains. Definiteness in outline disappears with the age of the culture. More striking variations are found in the virulence of the different strains for the monkey (Macacus rhesus). Three of the nine strains isolated proved to be non-pathogenic for the monkeys. All three of these were derived from cases of benign verruga. The remaining six strains all gave rise to local lesions when intradermally inoculated and were recovered in culture from the blood of the animals

  10. Viral arthritis

    MedlinePlus

    Infectious arthritis - viral ... Arthritis may be a symptom of many virus-related illnesses. It usually disappears on its own without ... the rubella vaccine, only a few people develop arthritis. No risk factors are known.

  11. Viral Infections

    MedlinePlus

    ... much smaller than bacteria. Viruses cause familiar infectious diseases such as the common cold, flu and warts. ... can help prevent you from getting many viral diseases. NIH: National Institute of Allergy and Infectious Diseases

  12. Viral Gastroenteritis

    MedlinePlus

    ... stomach, small intestine, and large intestine. Several different viruses can cause viral gastroenteritis, which is highly contagious ... and last for 1 to 3 days. Some viruses cause symptoms that last longer. [ Top ] What are ...

  13. Viral pneumonia

    MedlinePlus

    More serious infections can result in respiratory failure, liver failure, and heart failure. Sometimes, bacterial infections occur during or just after viral pneumonia, which may lead to more serious forms ...

  14. Pharyngitis - viral

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/001392.htm Pharyngitis - viral To use the sharing features on this page, please enable JavaScript. Pharyngitis , or sore throat, is swelling, discomfort, pain, or ...

  15. Etiologies of Sarcoidosis.

    PubMed

    Chen, Edward S; Moller, David R

    2015-08-01

    Since sarcoidosis was first described more than a century ago, the etiologic determinants causing this disease remain uncertain. Studies suggest that genetic, host immunologic, and environmental factors interact together to cause sarcoidosis. Immunologic characteristics of sarcoidosis include non-caseating granulomas, enhanced local expression of T helper-1 (and often Th17) cytokines and chemokines, dysfunctional regulatory T-cell responses, dysregulated Toll-like receptor signaling, and oligoclonal expansion of CD4+ T cells consistent with chronic antigenic stimulation. Multiple environmental agents have been suggested to cause sarcoidosis. Studies from several groups implicate mycobacterial or propionibacterial organisms in the etiology of sarcoidosis based on tissue analyses and immunologic responses in sarcoidosis patients. Despite these studies, there is no consensus on the nature of a microbial pathogenesis of sarcoidosis. Some groups postulate sarcoidosis is caused by an active viable replicating infection while other groups contend there is no clinical, pathologic, or microbiologic evidence for such a pathogenic mechanism. The authors posit a novel hypothesis that proposes that sarcoidosis is triggered by a hyperimmune Th1 response to pathogenic microbial and tissue antigens associated with the aberrant aggregation of serum amyloid A within granulomas, which promotes progressive chronic granulomatous inflammation in the absence of ongoing infection. PMID:25771769

  16. Non-viral causes of hepatocellular carcinoma

    PubMed Central

    Blonski, Wojciech; Kotlyar, David S; Forde, Kimberly A

    2010-01-01

    Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and represents an international public health concern as one of the most deadly cancers worldwide. The main etiology of HCC is chronic infection with hepatitis B and hepatitis C viruses. However, there are other important factors that contribute to the international burden of HCC. Among these are obesity, diabetes, non-alcoholic steatohepatitis and dietary exposures. Emerging evidence suggests that the etiology of many cases of HCC is in fact multifactorial, encompassing infectious etiologies, comorbid conditions and environmental exposures. Clarification of relevant non-viral causes of HCC will aid in preventative efforts to curb the rising incidence of this disease. PMID:20677332

  17. Expression of chicken interleukin-2 by a highly virulent strain of Newcastle disease virus leads to decreased systemic viral load but does not significantly affect mortality in chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In mammals, interleukin 2 (IL-2) has been shown to decrease replication or attenuate pathogenicity of numerous viral pathogens by activating natural killer cells (NK), cytotoxic T lymphocytes, and expanding subsets of memory cells. In chickens, IL-2 has been shown to activate T cells, and as such i...

  18. [Hepatoblastoma, Etiology, Case Reports].

    PubMed

    Puchmajerová, A; Křepelová, A; Indráková, J; Sítková, R; Balaščak, I; Kruseová, J; Švojgr, K; Kodet, R; Kynčl, M; Vícha, A; Macek, M

    2016-01-01

    Hepatoblastoma is an uncommon malignant neoplasm in general, yet, it is the most common liver malignancy in children with the incidence about one per milion children. This type of liver tumor usually occurs before the age of three years. The etiology of hepatoblastoma remains unknown. However, there are some genetic conditions known to be associated with an increased risk of developing hepatoblastoma such as Beckwith-Wiedemann syndrome, hemihypertrophy, APC-associated polyposis, α-1-antitrypsin defficiency and some metabolic disorders including tyrosinemia, galactosemia and glycogen storage disease type 1. There is a higher risk of hepatoblastoma in children with very low birthweight, children who acquire hepatitis B at an early age and children with congenital biliary atresia. PMID:26691946

  19. Viral arthritis.

    PubMed

    Marks, Michael; Marks, Jonathan L

    2016-04-01

    Acute-onset arthritis is a common clinical problem facing both the general clinician and the rheumatologist. A viral aetiology is though to be responsible for approximately 1% of all cases of acute arthritis with a wide range of causal agents recognised. The epidemiology of acute viral arthritis continues to evolve, with some aetiologies, such as rubella, becoming less common due to vaccination, while some vector-borne viruses have become more widespread. A travel history therefore forms an important part of the assessment of patients presenting with an acute arthritis. Worldwide, parvovirus B19, hepatitis B and C, HIV and the alphaviruses are among the most important causes of virally mediated arthritis. Targeted serological testing may be of value in establishing a diagnosis, and clinicians must also be aware that low-titre autoantibodies, such as rheumatoid factor and antinuclear antibody, can occur in the context of acute viral arthritis. A careful consideration of epidemiological, clinical and serological features is therefore required to guide clinicians in making diagnostic and treatment decisions. While most virally mediated arthritides are self-limiting some warrant the initiation of specific antiviral therapy. PMID:27037381

  20. Viral quasispecies

    PubMed Central

    Andino, Raul; Domingo, Esteban

    2016-01-01

    New generation sequencing is greatly expanding the capacity to examine the composition of mutant spectra of viral quasispecies in infected cells and host organisms. Here we review recent progress in the understanding of quasispecies dynamics, notably the occurrence of intra-mutant spectrum interactions, and implications of fitness landscapes for virus adaptation and de-adaptation. Complementation or interference can be established among components of the same mutant spectrum, dependent on the mutational status of the ensemble. Replicative fitness relates to an optimal mutant spectrum that provides the molecular basis for phenotypic flexibility, with implications for antiviral therapy. The biological impact of viral fitness renders particularly relevant the capacity of new generation sequencing to establish viral fitness landscapes. Progress with experimental model systems is becoming an important asset to understand virus behavior in the more complex environments faced during natural infections. PMID:25824477

  1. STUDIES OF WATERBORNE AGENTS OF VIRAL GASTROENTERITIS

    EPA Science Inventory

    The etiologic agent of a large outbreak of waterborne viral gastroenteritis was detected employing immune electron microscopy (IEM) and a newly developed solid phase radioimmunoassay (RIA). This agent, referred to as the Snow Mountain Agent (SMA), is 27-32 nm. in diameter, has cu...

  2. The etiology of osteosarcoma.

    PubMed

    Ottaviani, Giulia; Jaffe, Norman

    2009-01-01

    Studies to determine the etiology of osteosarcoma involve epidemiologic and environmental factors and genetic impairments. Factors related to patient characteristics include age, gender, ethnicity, growth and height, genetic and familial factors, and preexisting bone abnormalities. Rapidly proliferating cells may be particularly susceptible to oncogenic agents and mitotic errors which lead to neoplastic transformation. Genetic aberrations that accompany osteosarcoma have received increasing recognition as an important factor in its etiology. Osteosarcoma tumor cells exhibit karyotypes with a high degree of complexity which has made it difficult to determine whether any recurrent chromosomal aberrations characterize osteosarcoma. Although extremely rare, osteosarcoma has occasionally been observed in several members of the same family. No other clinical abnormalities in the proband or the affected members were reported. Pathologic examination of the tumors revealed no unusual features. Genetic testing was not available in most of these reports. The patients generally responded to conventional therapy. A genetic predisposition to osteosarcoma is found in patients with hereditary retinoblastoma, characterized by mutation of the retinoblastoma gene RB1 on chromosome 13q14. The Rothmund-Thomson syndrome is an autosomal recessive disorder with a heterogeneous clinical profile. Patients may have a few or multiple clinical features including skin rash, small stature, skeletal dysplasias, sparse or absent scalp hair, eyebrows or eyelashes, juvenile cataracts, and gastrointestinal disturbance including chronic emesis and diarrhea; its molecular basis is the mutation in the RECQL4 gene in a subset of cases. The Li-Fraumeni syndrome is an autosomal dominant disorder characterized by a high risk of developing osteosarcoma and has been found in up to 3% of children with osteosarcoma. It is associated with a germline mutation of the p53, a suppressor gene. The following three

  3. Viral Hepatitis

    MedlinePlus

    ... with hepatitis? How does a pregnant woman pass hepatitis B virus to her baby? If I have hepatitis B, what does my baby need so that she ... Can I breastfeed my baby if I have hepatitis B? More information on viral hepatitis What is hepatitis? ...

  4. VIRAL GASTROENTERITIS

    EPA Science Inventory

    Two virus types have been clearly shown to have epidemiologic importance in viral gastroenteritis, i.e., rotavirus and Norwalk virus. Four other virus types have been associated with gastroenteritis but their epidemiologic importance is not yet known, i.e., enteric adenovirus, ca...

  5. Friend strain of spleen focus-forming virus: a recombinant between mouse type C ecotropic viral sequences and sequences related to xenotropic virus.

    PubMed Central

    Troxler, D H; Boyars, J K; Parks, W P; Scolnick, E M

    1977-01-01

    The genome of the Friend strain of the spleen focus-forming virus (SFFV) has been analyzed by molecular hybridization. SFFV is composed of genetic sequences homologous to Friend type C helper virus (F-MuLV) and SFFV-specific sequences not present in F-MuLV. These SFFV-specific sequences are present in both the Friend and Rauscher strains of murine erythroleukemia virus. The SFFV-specific sequences are partially homologous to three separate strains of mouse xenotropic virus but not to several cloned mouse ecotropic viruses. Thus, the Friend strain of SFFV appears to be a recombinant between a portion of the F-MuLV genome and RNA sequences that are highly related to murine xenotropic viruses. The implications of the acquisition of the xenotropic virus-related sequences are discussed in relation to the leukemogenicity of SFFV, and a model for the pathogenicity of other murine leukemia-inducing viruses is proposed. PMID:194058

  6. CpG oligodeoxynucleotide-specific goose TLR21 initiates an anti-viral immune response against NGVEV but not AIV strain H9N2 infection.

    PubMed

    Qi, Yulin; Yan, Bing; Chen, Shun; Chen, Hongjun; Wang, Mingshu; Jia, Renyong; Zhu, Dekang; Liu, Mafeng; Liu, Fei; Yang, Qiao; Sun, Kunfeng; Wu, Ying; Chen, Xiaoyue; Jing, Bo; Cheng, Anchun

    2016-03-01

    Toll-like receptors (TLRs) recognize components of pathogens and mediate the host innate immune response. TLR21 is a TLR that specifically recognizes exogenous double-stranded DNA and rapidly signals to downstream innate immune factors. This study reports the cDNA of goose TLR21 and identifies its immune characteristics. The goose TLR21 is 3161 base pairs and encodes a 975 amino acid protein. As predicted, the goose transmembrane protein TLR21 has a signal peptide, leucine-rich repeat regions, a transmembrane domain, and a Toll/interleukin-1 receptor domain. Multiple sequence alignments and phylogenetic analyses showed that goose TLR21 has homology to chicken TLR21. The tissue distribution of TLR21 suggested that it has high transcript levels in immune-associated tissues, especially in the bursa of Fabricius, the Hadrian gland, and the thymus. After challenge with agonist ODN2006 and new type gosling viral enteritis virus (NGVEV), significant induction of TLR21 production, pro-inflammatory cytokines IL-1β and IL-6, and interferons were observed in peripheral blood mononuclear cells. Both synthetic DNA (ODN2006) and viral DNA (NGVEV) can be recognized by goose TLR21, which leads to a rapid up-regulation of pro-inflammatory cytokines and anti-viral molecules. In vivo, avian influenza A virus H9N2 and NGVEV were used to infect goslings, which was followed by a significant up-regulation of TLR21 mRNA transcripts in multiple tissues of NGVEV-infected geese. In general, goose TLR21 plays an important role in binding invading pathogenic DNA viruses, which subsequently triggers an innate immune response; furthermore, it acts as a functional homologue of mammalian TLR9, as TLR21 recognizes a mammalian TLR9 agonist. PMID:26621545

  7. Diagnosis and Control of Viral Diseases of Reproductive Importance: Infectious Bovine Rhinotracheitis and Bovine Viral Diarrhea.

    PubMed

    Newcomer, Benjamin W; Givens, Daniel

    2016-07-01

    Both bovine viral diarrhea virus and bovine herpesvirus 1 can have significant negative reproductive impacts on cattle health. Vaccination is the primary control method for the viral pathogens in US cattle herds. Polyvalent, modified-live vaccines are recommended to provide optimal protection against various viral field strains. Of particular importance to bovine viral diarrhea control is the limitation of contact of pregnant cattle with potential viral reservoirs during the critical first 125 days of gestation. PMID:27140298

  8. Evolutionary etiology of high-grade astrocytomas

    PubMed Central

    Song, Yurong; Zhang, Qian; Kutlu, Burak; Difilippantonio, Simone; Bash, Ryan; Gilbert, Debra; Yin, Chaoying; O’Sullivan, T. Norene; Yang, Chunyu; Kozlov, Serguei; Bullitt, Elizabeth; McCarthy, Ken D.; Kafri, Tal; Louis, David N.; Miller, C. Ryan; Hood, Leroy; Van Dyke, Terry

    2013-01-01

    Glioblastoma (GBM), the most common brain malignancy, remains fatal with no effective treatment. Analyses of common aberrations in GBM suggest major regulatory pathways associated with disease etiology. However, 90% of GBMs are diagnosed at an advanced stage (primary GBMs), providing no access to early disease stages for assessing disease progression events. As such, both understanding of disease mechanisms and the development of biomarkers and therapeutics for effective disease management are limited. Here, we describe an adult-inducible astrocyte-specific system in genetically engineered mice that queries causation in disease evolution of regulatory networks perturbed in human GBM. Events yielding disease, both engineered and spontaneous, indicate ordered grade-specific perturbations that yield high-grade astrocytomas (anaplastic astrocytomas and GBMs). Impaired retinoblastoma protein RB tumor suppression yields grade II histopathology. Additional activation of v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) network drives progression to grade III disease, and further inactivation of phosphatase and tensin homolog (PTEN) yields GBM. Spontaneous missense mutation of tumor suppressor Trp53 arises subsequent to KRAS activation, but before grade III progression. The stochastic appearance of mutations identical to those observed in humans, particularly the same spectrum of p53 amino acid changes, supports the validity of engineered lesions and the ensuing interpretations of etiology. Absence of isocitrate dehydrogenase 1 (IDH1) mutation, asymptomatic low grade disease, and rapid emergence of GBM combined with a mesenchymal transcriptome signature reflect characteristics of primary GBM and provide insight into causal relationships. PMID:24114272

  9. Molecular biology of bovine viral diarrhea virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine viral diarrhea viruses (BVDV) are arguably the most important viral pathogen of ruminants worldwide and can cause severe economic loss. Clinical symptoms of the disease caused by BVDV range from subclinical to severe acute hemorrhagic syndrome, with the severity of disease being strain depend...

  10. [Etiology of adult insomnia].

    PubMed

    Dollander, M

    2002-01-01

    In the article, the author develops an analysis of external and intrapsychic factors related to adults' insomnia. First she undertakes a literature review to describe semiological, evolutive and etiological levels of insomnia. From a semiological point of view, it is usual to differenciate initial insomnia (associated to the first phase of sleeping), intermittent insomnia (related to frequent awakenings) and final insomnia (related to early morning awakenings). From an evolutive point of view, we can identify transitory insomnia (characterized by frequent awakenings) and chronic insomnia. On the other hand, we are allowed to distinguish organic insomnia (disorder where an organic cerebral injury is demonstrated or suspected) from insomnias related to psychiatric or somatic disease or idiopathic one. Then, the author makes a literary review to identify various insomnia causes and points out. Social factors: insomnia rates are higher by divorced, separated or widowed people. Percentages are higher when scholastic level is weak, domestic income is less then 915 O a month, or by unemployed people. Besides, sleep quality is deteriorated by ageing. Sleeping and waking rhythm is able to loose its synchronization. Complaints about insomnia occur far frequently from women than men. Environmental factors: working constraints increase sleep disorders. It is possible to make the same conclusion when we have to face overcharge of external events, deep intrapsychic conflicts (related to grief, unemployment, damage or hospitalization) or interpersonal conflicts' situations where we are confronted to stress related to socio-affective environment, lack of social support or conjugal difficulties. Medical and physiologic causes: legs impatience syndrome, recurrent limbs shakings syndrome, breathe stop during sleep, narcolepsy, excessive medicine or hypnotic drugs use, some central nervous system injuries, every nocturnal awakening (related to aches.), surgical operation

  11. A novel recombinant strain of Potato virus Y allows identification of a new viral genetic determinant of vein necrosis in tobacco

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel Potato virus Y (PVY) isolate, L26, recovered from a Frontier potato line was initially typed as a PVYNTN strain using multiplex RT-PCR and serological assays. However, L26 induced mosaic and mild vein clearing symptoms in tobacco rather than vein necrosis characteristic of the PVY NTN strai...

  12. Attenuation of Vaccinia Tian Tan Strain by Removal of Viral TC7L-TK2L and TA35R Genes

    PubMed Central

    Kan, Shifu; Wang, Yuhang; Sun, Lili; Jia, Peng; Qi, Yanxin; Su, Jiaqiang; Liu, Lei; Yang, Guohua; Liu, Liming; Wang, Zhuoyue; Wang, Jinhui; Liu, Guangchen; Jin, Ningyi; Li, Xiao; Ding, Zhuang

    2012-01-01

    Vaccinia Tian Tan (VTT) was attenuated by deletion of the TC7L-TK2L and TA35R genes to generate MVTT3. The mutant was generated by replacing the open reading frames by a gene encoding enhanced green fluorescent protein (EGFP) flanked by loxP sites. Viruses expressing EGFP were then screened for and purified by serial plaque formation. In a second step the marker EGFP gene was removed by transfecting cells with a plasmid encoding cre recombinase and selecting for viruses that had lost the EGFP phenotype. The MVTT3 mutant was shown to be avirulent and immunogenic. These results support the conclusion that TC7L-TK2L and TA35R deletion mutants can be used as safe viral vectors or as platform for vaccines. PMID:22363781

  13. Sequencing and Phylogenetic Analysis of Near Full-Length HIV-1 Subtypes A, B, G and Unique Recombinant AC and AD Viral Strains Identified in South Africa

    PubMed Central

    Wilkinson, Eduan; Holzmayer, Vera; Jacobs, Graeme B.; de Oliveira, Tulio; Brennan, Catherine A.; Hackett, John; van Rensburg, Estrelita Janse

    2015-01-01

    Abstract By the end of 2012, more than 6.1 million people were infected with HIV-1 in South Africa. Subtype C was responsible for the majority of these infections and more than 300 near full-length genomes (NFLGs) have been published. Currently very few non-subtype C isolates have been identified and characterized within the country, particularly full genome non-C isolates. Seven patients from the Tygerberg Virology (TV) cohort were previously identified as possible non-C subtypes and were selected for further analyses. RNA was isolated from five individuals (TV047, TV096, TV101, TV218, and TV546) and DNA from TV016 and TV1057. The NFLGs of these samples were amplified in overlapping fragments and sequenced. Online subtyping tools REGA version 3 and jpHMM were used to screen for subtypes and recombinants. Maximum likelihood (ML) phylogenetic analysis (phyML) was used to infer subtypes and SimPlot was used to confirm possible intersubtype recombinants. We identified three subtype B (TV016, TV047, and TV1057) isolates, one subtype A1 (TV096), one subtype G (TV546), one unique AD (TV101), and one unique AC (TV218) recombinant form. This is the first NFLG of subtype G that has been described in South Africa. The subtype B sequences described also increased the NFLG subtype B sequences in Africa from three to six. There is a need for more NFLG sequences, as partial HIV-1 sequences may underrepresent viral recombinant forms. It is also necessary to continue monitoring the evolution and spread of HIV-1 in South Africa, because understanding viral diversity may play an important role in HIV-1 prevention strategies. PMID:25492033

  14. BamI, KpnI, and SalI restriction enzyme maps of the DNAs of herpes simplex virus strains Justin and F: occurrence of heterogeneities in defined regions of the viral DNA.

    PubMed Central

    Locker, H; Frenkel, N

    1979-01-01

    We present the locations of the cleavage sites for the BamI, KpnI, and SalI restriction endonucleases within the DNA molecules of herpes simplex virus type 1 (HSV-1) strains Justin and F. These restriction enzymes cleave the HSV-1 DNA at many sites, producing relatively small fragments which should prove useful in future studies of HSV-1 gene structure and function. The mapping data revealed the occurrence of heterogeneity within three regions of the viral genome including (i) the region spanning map coordinates 0.74--0.76, (ii) the ends of the large (L) DNA component, and (iii) the junction between the large (L) and the small (S) components. The heterogeneity in the ends of L and the S-L junctions of HSV-1 (Justin) and HSV-1 (F) DNAs was grossly similar to that previously reported to occur in the ends of L and the S-L junctions of the HSV-1 (KOS) DNA (M. J. Wagner and W. C. Summers, J. Virol. 27:374--387, 1978). Thus, cleavage of these regions with restriction endonucleases yielded sets of minor fragments differing in size by constant increments. However, the various strains of HSV-1 differed with respect to the numbers, size increments, and relative molarities of the various minor fragments, suggesting that the parameters of the heterogeneity are inherited in the structural makeup of the HSV-1 genome. The strain dependence of the pattern of heterogeneity can be most easily explained in terms of variable sizes of the terminally reiterated a sequence, contained in the DNA molecules of these three strains of HSV-1. Images PMID:228068

  15. Emergence of clusters of CRF02_AG and B human immunodeficiency viral strains among men having sex with men exhibiting HIV primary infection in southeastern France.

    PubMed

    Tamalet, Catherine; Ravaux, Isabelle; Moreau, Jacques; Brégigeon, Sylvie; Tourres, Christian; Richet, Hervé; Abat, Cedric; Colson, Philippe

    2015-08-01

    The number of new HIV diagnoses is increasing in the western world and transmission clusters have been recently identified among men having sex with men despite Highly Active Antiretroviral Therapy efficacy. The objective of this study was to assess temporal trends, epidemiological, clinical and virological characteristics of primary HIV infections. A retrospective analysis of 79 patients presenting primary HIV infections from 2005 to 2012 was performed in Marseille University Hospitals, southeastern France. Clinical, epidemiological and immunovirological data including phylogeny based on the polymerase gene were collected. 65 males and 14 females were enrolled. The main transmission route was homosexual contact (60.8%). Patients were mostly infected with subtype B (73.4%) and CRF02_AG (21.5%) HIV-1 strains. An increase in the annual number of HIV seroconversions among new HIV diagnoses from 5% in 2005 to 11.2% in 2012 (P = 0.06) and of the proportion of CRF02_AG HIV strains among primary HIV infections in 2011-2012 as compared to 2005-2010 (P = 0.055) was observed. Phylogenetic analysis revealed four transmission clusters including three transmission clusters among men having sex with men: two large clusters of nine CRF02_AG, six B HIV strains; and one small cluster of three B HIV strains. Clusters involved more frequently men (P = 0.01) belonging to caucasian ethicity (P = 0.05), with a higher HIV RNA load at inclusion (P = 0.03). These data highlight the importance of improving epidemiological surveillance and of implementing suitable prevention strategies to control the spread of HIV transmission among men having sex with men. PMID:25873310

  16. [The role of respiratory tract viruses in the etiology of obstructive bronchitis in infants].

    PubMed

    Wilczyński, J; Jankowski, M; Torbicka, E; Roszkowska-Sliz, L; Kurkiewicz, E

    1990-01-01

    Out of 524 children with acute respiratory infections in 141 obstructive bronchitis was diagnosed (OZO). Seventy cases could be linked to viral infection. Viral infections tested (influenza virus A, B, parainfluenza typ 1-3, RSV, adenoviruses) were more frequently associated with OZO than other acute respiratory infections of unknown etiology. Majority infections induced by influenza virus A and parainfluenza virus typ 2 were accompanied by OZO symptoms. Of the highest risk of acquiring OZO despite of viral infection participation, were children of 4-12 months of age. OZO associated viral infections prevailed during autumn-winter season, while in spring-summer period undetermined factors were the major cause of OZO. In serum samples of children with OZO, despite of etiology of the disease, higher level of IgE was found than in a group of children without the symptoms. In the case of OZO of unestablished etiology the level of serum IgE was significantly higher than in the cases when viral etiology of the disease was found. PMID:2084449

  17. Spectrum of Etiologies Causing Hydrometrocolpos

    PubMed Central

    Kurt, Gökmen; Sahin, Ceyhan; Cici, Inanç

    2013-01-01

    Background: Hydrometrocolpos (HMC) develops as a result of vaginal outflow obstruction and the accumulation of secretions. It might be secondary to persistent cloaca, urogenital sinus, some syndromes, presence of the vaginal septum, vaginal atresia, and imperforate hymen. Each of them has different treatment options and follow-up protocols. This study was performed to identify the etiology and the related management of patients with HMC. Materials and Methods: A descriptive series of patients with HMC managed in our hospital between 2004 and 2011 is being presented. The medical record of these patients was analyzed for etiology, management, and outcome. Results: Eight patients with HMC were managed during 7 years at our department. Underlying etiologies included urogenital sinus (n=3), and 1 each of imperforate hymen, transverse vaginal septum, Herlyn-Werner-Wunderlich syndrome, persistent cloaca, and a variant of the cloaca. Four patients were prenatally diagnosed. The patient with imperforate hymen was managed successfully with incision and drainage. Abdominal vaginostomy was done in three patients with urogenital sinus as initial procedure. In patient with persistent cloaca, a colostomy and abdominal vaginostomy were performed. Patient with cloaca variant died due to persistent acidosis and salt wasting. Conclusion: HMC may have different etiological factors which may dictate different surgical management. Etiology of HMC can be as simple as imperforate hymen to the most severe cloacal malformations. PMID:26023425

  18. An Etiological Model of Perfectionism

    PubMed Central

    Maloney, Gayle K.; Egan, Sarah J.; Kane, Robert T.; Rees, Clare S.

    2014-01-01

    Objective Perfectionism has been recognized as a transdiagnostic factor that is relevant to anxiety disorders, eating disorders and depression. Despite the importance of perfectionism in psychopathology to date there has been no empirical test of an etiological model of perfectionism. Method The present study aimed to address the paucity of research on the etiology of perfectionism by developing and testing an etiological model using a sample of 311 clients seeking treatment. Results Structural equation modeling showed a direct relationship between high Parental Expectations and Criticism, and Perfectionism. There was also an indirect relationship between Parental Bonding and Perfectionism that was mediated by core schemas of disconnection and rejection. Finally, it was found that Neuroticism had both an indirect relationship, which was mediated by core schemas, and a direct relationship with perfectionism. Conclusions The study provided the first direct test of an etiological model of perfectionism to date. Clinical implications include investigating whether the inclusion of etiological factors in the understanding and treatment of perfectionism is effective. PMID:24787357

  19. Viral diseases and pathogenesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It includes classification of viral infection. It describes common ways of virus entry, replication, and transmission. It introduces the routes of viral invasion and molecular basis for viral pathogenesis....

  20. High-Pressure Inactivation of Rotaviruses: Role of Treatment Temperature and Strain Diversity in Virus Inactivation.

    PubMed

    Araud, Elbashir; DiCaprio, Erin; Yang, Zhihong; Li, Xinhui; Lou, Fangfei; Hughes, John H; Chen, Haiqiang; Li, Jianrong

    2015-10-01

    Rotavirus (RV) is the major etiological agent of acute gastroenteritis in infants worldwide. Although high-pressure processing (HPP) is a popular method to inactivate enteric pathogens in food, the sensitivity of different virus strains within same species and serotype to HPP is variable. This study aimed to compare the barosensitivities of seven RV strains derived from four serotypes (serotype G1, strains Wa, Ku, and K8; serotype G2, strain S2; serotype G3, strains SA-11 and YO; and serotype G4, strain ST3) following high-pressure treatment. RV strains showed various responses to HPP based on the initial temperature and had different inactivation profiles. Ku, K8, S2, SA-11, YO, and ST3 showed enhanced inactivation at 4°C compared to 20°C. In contrast, strain Wa was not significantly impacted by the initial treatment temperature. Within serotype G1, strain Wa was significantly (P < 0.05) more resistant to HPP than strains Ku and K8. Overall, the resistance of the human RV strains to HPP at 4°C can be ranked as Wa > Ku = K8 > S2 > YO > ST3, and in terms of serotype the ranking is G1 > G2 > G3 > G4. In addition, pressure treatment of 400 MPa for 2 min was sufficient to eliminate the Wa strain, the most pressure-resistant RV, from oyster tissues. HPP disrupted virion structure but did not degrade viral protein or RNA, providing insight into the mechanism of viral inactivation by HPP. In conclusion, HPP is capable of inactivating RV at commercially acceptable pressures, and the efficacy of inactivation is strain dependent. PMID:26187961

  1. Viral evolution

    PubMed Central

    Nasir, Arshan; Kim, Kyung Mo; Caetano-Anollés, Gustavo

    2012-01-01

    Explaining the origin of viruses remains an important challenge for evolutionary biology. Previous explanatory frameworks described viruses as founders of cellular life, as parasitic reductive products of ancient cellular organisms or as escapees of modern genomes. Each of these frameworks endow viruses with distinct molecular, cellular, dynamic and emergent properties that carry broad and important implications for many disciplines, including biology, ecology and epidemiology. In a recent genome-wide structural phylogenomic analysis, we have shown that large-to-medium-sized viruses coevolved with cellular ancestors and have chosen the evolutionary reductive route. Here we interpret these results and provide a parsimonious hypothesis for the origin of viruses that is supported by molecular data and objective evolutionary bioinformatic approaches. Results suggest two important phases in the evolution of viruses: (1) origin from primordial cells and coexistence with cellular ancestors, and (2) prolonged pressure of genome reduction and relatively late adaptation to the parasitic lifestyle once virions and diversified cellular life took over the planet. Under this evolutionary model, new viral lineages can evolve from existing cellular parasites and enhance the diversity of the world’s virosphere. PMID:23550145

  2. Clinical presentation, etiology, and survival in adult acute encephalitis syndrome in rural Central India

    PubMed Central

    Joshi, Rajnish; Mishra, Pradyumna Kumar; Joshi, Deepti; Santhosh, SR; Parida, M.M.; Desikan, Prabha; Gangane, Nitin; Kalantri, S.P.; Reingold, Arthur; Colford, John M.

    2013-01-01

    Background Acute encephalitis syndrome (AES) is a constellation of symptoms that includes fever and altered mental status. Most cases are attributed to viral encephalitis (VE), occurring either in outbreaks or sporadically. We conducted hospital-based surveillance for sporadic adult-AES in rural Central India in order to describe its incidence, spatial and temporal distribution, clinical profile, etiology and predictors of mortality. Methods All consecutive hospital admissions during the study period were screened to identify adult-AES cases and were followed until 30-days of hospitalization. We estimated incidence by administrative sub-division of residence and described the temporal distribution of cases. We performed viral diagnostic studies on cerebrospinal fluid (CSF) samples to determine the etiology of AES. The diagnostic tests included RT-PCR (for enteroviruses, HSV 1 and 2), conventional PCR (for flaviviruses), CSF IgM capture ELISA (for Japanese encephalitis virus, dengue, West Nile virus, Varicella zoster virus, measles, and mumps). We compared demographic and clinical variables across etiologic subtypes and estimated predictors of 30-day mortality. Results A total of 183 AES cases were identified between January and October 2007, representing 2.38% of all admissions. The incidence of adult AES in the administrative subdivisions closest to the hospital was 16 per 100,000. Of the 183 cases, a non-viral etiology was confirmed in 31 (16.9%) and the remaining 152 were considered as VE suspects. Of the VE suspects, we could confirm a viral etiology in 31 cases: 17 (11.2%) enterovirus; 8 (5.2%) flavivirus; 3 (1.9%) Varicella zoster; 1 (0.6%) herpesvirus; and 2 (1.3%) mixed etiology); the etiology remained unknown in remaining 121 (79.6%) cases. 53 (36%) of the AES patients died; the case fatality proportion was similar in patients with a confirmed and unknown viral etiology (45.1 and 33.6% respectively). A requirement for assisted ventilation significantly

  3. [Etiology and treatment of thrombocytopenia].

    PubMed

    Bargetzi, M J

    2004-02-01

    Thrombocytopenia has many causes. History, clinical examination of the patient, and a careful analysis of the peripheral blood smear may already lead to the etiology of cytopenia. The aim of the treatment is the correction of the underlying disease. In the management of immune thrombocytopenic purpura, the most common form of thrombocytopenia in adults, the goal is to avoid hemorrhages and not to increase the platelet value to normal. PMID:15018402

  4. Viral encephalitis: current treatments and future perspectives.

    PubMed

    Domingues, Renan Barros

    2012-12-01

    Several viruses may cause central nervous system infections that lead to a broad range of clinical manifestations. The course of the viral encephalitis can be acute, sub acute, or chronic. Some viruses have the ability to enter into the brain and cause direct injury, while others activate inflammatory cells that attack the central nervous system (CNS) secondarily. Some types of viral encephalitis occur in previously healthy individuals, while others affect immunocompromised patients. The epidemiology of viral encephalitis has undergone changes in recent years. Factors such as evolving lifestyles and ecological changes have had a considerable impact on the epidemiology of some types of viral encephalitis. The result is a change in the etiology spectrum of viral encephalitis, with new types of encephalitis arising or returning from time to time. Many scientific achievements in neuroimaging, molecular diagnosis, antiviral therapy, immunomodulatory treatments, and neurointensive care have allowed more precise and earlier diagnoses and more efficient treatments, resulting in improved outcomes. Despite these advances, there is still considerable morbidity and mortality related to these disorders. This aim of this article is to review the current knowledge of the current drugs used in the management of the most important viral encephalitis, focusing on the mechanisms of action, efficacy, and side effects of the drugs. In addition, future perspectives in this area will be addressed. Despite the technological advances, much effort has yet to be undertaken to reduce the impact of these potentially devastating diseases. PMID:22640219

  5. THE ETIOLOGY OF BACTERIAL VAGINOSIS

    PubMed Central

    Turovskiy, Yevgeniy; Noll, Katia Sutyak; Chikindas, Michael L.

    2011-01-01

    Bacterial vaginosis (BV) is the most common vaginal infection among women of childbearing age. This condition is notorious for causing severe complications related to the reproductive health of women. Five decades of intense research established many risk factors for acquisition of BV, however due to the complexity of BV and due to lack of a reliable animal model for this condition, its exact etiology remains elusive. In this manuscript we use a historical perspective to critically review the development of major theories on the etiology of BV, ultimately implicating BV-related pathogens, healthy vaginal microbiota, bacteriophages and the immune response of the host. None of these theories on their own can reliably explain the epidemiological data. Instead, BV is caused by a complex interaction of multiple factors, which include the numerous components of the vaginal microbial ecosystem and their human host. Many of these factors are yet to be characterized because a clear understanding of their relative contribution to the etiology of BV is pivotal to formulation of an effective treatment for and prophylaxis of this condition. PMID:21332897

  6. Epigenetics and Genetics of Viral Latency.

    PubMed

    Lieberman, Paul M

    2016-05-11

    Viral latency can be considered a metastable, nonproductive infection state that is capable of subsequent reactivation to repeat the infection cycle. Viral latent infections have numerous associated pathologies, including cancer, birth defects, neuropathy, cardiovascular disease, chronic inflammation, and immunological dysfunctions. The mechanisms controlling the establishment, maintenance, and reactivation from latency are complex and diversified among virus families, species, and strains. Yet, as examined in this review, common properties of latent viral infections can be defined. Eradicating latent virus has become an important but elusive challenge and will require a more complete understanding of the mechanisms controlling these processes. PMID:27173930

  7. ViralZone: a knowledge resource to understand virus diversity.

    PubMed

    Hulo, Chantal; de Castro, Edouard; Masson, Patrick; Bougueleret, Lydie; Bairoch, Amos; Xenarios, Ioannis; Le Mercier, Philippe

    2011-01-01

    The molecular diversity of viruses complicates the interpretation of viral genomic and proteomic data. To make sense of viral gene functions, investigators must be familiar with the virus host range, replication cycle and virion structure. Our aim is to provide a comprehensive resource bridging together textbook knowledge with genomic and proteomic sequences. ViralZone web resource (www.expasy.org/viralzone/) provides fact sheets on all known virus families/genera with easy access to sequence data. A selection of reference strains (RefStrain) provides annotated standards to circumvent the exponential increase of virus sequences. Moreover ViralZone offers a complete set of detailed and accurate virion pictures. PMID:20947564

  8. ViralZone: a knowledge resource to understand virus diversity

    PubMed Central

    Hulo, Chantal; de Castro, Edouard; Masson, Patrick; Bougueleret, Lydie; Bairoch, Amos; Xenarios, Ioannis; Le Mercier, Philippe

    2011-01-01

    The molecular diversity of viruses complicates the interpretation of viral genomic and proteomic data. To make sense of viral gene functions, investigators must be familiar with the virus host range, replication cycle and virion structure. Our aim is to provide a comprehensive resource bridging together textbook knowledge with genomic and proteomic sequences. ViralZone web resource (www.expasy.org/viralzone/) provides fact sheets on all known virus families/genera with easy access to sequence data. A selection of reference strains (RefStrain) provides annotated standards to circumvent the exponential increase of virus sequences. Moreover ViralZone offers a complete set of detailed and accurate virion pictures. PMID:20947564

  9. Infectious Etiologies of Acute Febrile Illness among Patients Seeking Health Care in South-Central Cambodia

    PubMed Central

    Kasper, Matthew R.; Blair, Patrick J.; Touch, Sok; Sokhal, Buth; Yasuda, Chadwick Y.; Williams, Maya; Richards, Allen L.; Burgess, Timothy H.; Wierzba, Thomas F.; Putnam, Shannon D.

    2012-01-01

    The agents of human febrile illness can vary by region and country suggesting that diagnosis, treatment, and control programs need to be based on a methodical evaluation of area-specific etiologies. From December 2006 to December 2009, 9,997 individuals presenting with acute febrile illness at nine health care clinics in south-central Cambodia were enrolled in a study to elucidate the etiologies. Upon enrollment, respiratory specimens, whole blood, and serum were collected. Testing was performed for viral, bacterial, and parasitic pathogens. Etiologies were identified in 38.0% of patients. Influenza was the most frequent pathogen, followed by dengue, malaria, and bacterial pathogens isolated from blood culture. In addition, 3.5% of enrolled patients were infected with more than one pathogen. Our data provide the first systematic assessment of the etiologies of acute febrile illness in south-central Cambodia. Data from syndromic-based surveillance studies can help guide public health responses in developing nations. PMID:22302857

  10. Viruses and Bacteria in the Etiology of the Common Cold

    PubMed Central

    Mäkelä, Mika J.; Puhakka, Tuomo; Ruuskanen, Olli; Leinonen, Maija; Saikku, Pekka; Kimpimäki, Marko; Blomqvist, Soile; Hyypiä, Timo; Arstila, Pertti

    1998-01-01

    Two hundred young adults with common colds were studied during a 10-month period. Virus culture, antigen detection, PCR, and serology with paired samples were used to identify the infection. Viral etiology was established for 138 of the 200 patients (69%). Rhinoviruses were detected in 105 patients, coronavirus OC43 or 229E infection was detected in 17, influenza A or B virus was detected in 12, and single infections with parainfluenza virus, respiratory syncytial virus, adenovirus, and enterovirus were found in 14 patients. Evidence for bacterial infection was found in seven patients. Four patients had a rise in antibodies against Chlamydia pneumoniae, one had a rise in antibodies against Haemophilus influenzae, one had a rise in antibodies against Streptococcus pneumoniae, and one had immunoglobulin M antibodies against Mycoplasma pneumoniae. The results show that although approximately 50% of episodes of the common cold were caused by rhinoviruses, the etiology can vary depending on the epidemiological situation with regard to circulating viruses. Bacterial infections were rare, supporting the concept that the common cold is almost exclusively a viral disease. PMID:9466772

  11. [Viral superantigens].

    PubMed

    Us, Dürdal

    2016-07-01

    , expression of endogenous SAgs leads to thymic deletion of responding T cells (bearing Vβ6-9+ TCR) due to self-tolerance induction during the fetal life, and protects the host against future exogenous MMTV infections. The SAg of rabies virus is the N protein found in nucleocapsid structure and stimulates Vβ8+TCR-bearing T cells. The SAg-induced polyclonal activation of T cells leads to turn-off the specific immune response, to enhance the immunopathogenesis and facilitates viral transmission from the initial site of infection (the muscle tissue) to the nerve endings. In case of EBV-associated SAg that activates Vβ13+TCR-bearing T cells, it was detected that the SAg activity was not encoded by EBV itself, but instead was due to the transactivation of HERV-K18 by EBV latent membrane proteins, whose env gene encodes the SAg (Sutkowski, et al. 2001). It has been denoted that EBV-induced SAg expression plays a role in the long-term persistence and latency of virus in memory B cells, in the development of autoimmune diseases and in the oncogenesis mechanisms. The proteins which are identified as SAgs of HIV are Nef and gp120. It is believed that, the massive activation of CD4+ T cells (selectively with Vβ-12+, Vβ-5.3+ and Vβ-18+ TCRs) in early stages of infection and clonal deletion, anergy and apoptosis of bystander T cells in the late stages may be due to SAg property of Nef protein, as well as the other mechanisms. However there are some studies indicating that Nef does not act as a SAg (Lapatschek, et al. 2001). HIV gp120 glycoprotein is a B-cell SAg that binds to VH3-expressing B cell receptors and causes polyclonal B cell activation. In addition, binding of gp120 to IgE on the surface of basophiles and mast cells causes activation of those cells, secretion of high level proinflammatory mediators leading to allergic reactions and tissue damage. In a recent study, the depletion (anergy or deletion) of T cell populations bearing Vβ12+, Vβ13+ and Vβ17+ TCR have been

  12. Sequencing Needs for Viral Diagnostics

    SciTech Connect

    Gardner, S N; Lam, M; Mulakken, N J; Torres, C L; Smith, J R; Slezak, T

    2004-01-26

    We built a system to guide decisions regarding the amount of genomic sequencing required to develop diagnostic DNA signatures, which are short sequences that are sufficient to uniquely identify a viral species. We used our existing DNA diagnostic signature prediction pipeline, which selects regions of a target species genome that are conserved among strains of the target (for reliability, to prevent false negatives) and unique relative to other species (for specificity, to avoid false positives). We performed simulations, based on existing sequence data, to assess the number of genome sequences of a target species and of close phylogenetic relatives (''near neighbors'') that are required to predict diagnostic signature regions that are conserved among strains of the target species and unique relative to other bacterial and viral species. For DNA viruses such as variola (smallpox), three target genomes provide sufficient guidance for selecting species-wide signatures. Three near neighbor genomes are critical for species specificity. In contrast, most RNA viruses require four target genomes and no near neighbor genomes, since lack of conservation among strains is more limiting than uniqueness. SARS and Ebola Zaire are exceptional, as additional target genomes currently do not improve predictions, but near neighbor sequences are urgently needed. Our results also indicate that double stranded DNA viruses are more conserved among strains than are RNA viruses, since in most cases there was at least one conserved signature candidate for the DNA viruses and zero conserved signature candidates for the RNA viruses.

  13. Viral-associated thrombotic microangiopathies.

    PubMed

    Lopes da Silva, Rodrigo

    2011-01-01

    Thrombotic microangiopathies encompass a group of disorders characterized by microangiopathic hemolytic anemia, thrombocytopenia associated with hyaline thrombi (comprised primarily of platelet aggregates in the microcirculation), and varying degrees of end-organ failure. Many primary (genetic) and secondary etiological predisposing factors have been described-namely pregnancy, autoimmune disorders, cancer, drugs and antineoplastic therapy, bone marrow transplantation/solid organ transplantation, and infections. In the setting of infectious diseases, the association with Shiga or Shiga-like exotoxin of Escherichia coli 0157:h7 or Shigella dysenteriae type 1-induced typical hemolytic uremic syndrome is well known. Recently however, an increasing body of evidence suggests that viruses may also play an important role as trigger factors in the pathogenesis of thrombotic microangiopathies. This is a comprehensive review focusing on the current understanding of viral associated/induced endothelial stimulation and damage that ultimately leads to the development of this life-threatening multisystemic disorder. PMID:21727765

  14. Viral Skin Diseases.

    PubMed

    Ramdass, Priya; Mullick, Sahil; Farber, Harold F

    2015-12-01

    In the vast world of skin diseases, viral skin disorders account for a significant percentage. Most viral skin diseases present with an exanthem (skin rash) and, oftentimes, an accompanying enanthem (lesions involving the mucosal membrane). In this article, the various viral skin diseases are explored, including viral childhood exanthems (measles, rubella, erythema infectiosum, and roseola), herpes viruses (herpes simplex virus, varicella zoster virus, Kaposi sarcoma herpes virus, viral zoonotic infections [orf, monkeypox, ebola, smallpox]), and several other viral skin diseases, such as human papilloma virus, hand, foot, and mouth disease, molluscum contagiosum, and Gianotti-Crosti syndrome. PMID:26612372

  15. Intrathoracic neoplasia: Epidemiology and etiology

    SciTech Connect

    Weller, R.E.

    1992-05-01

    Neoplasms of the thorax encompass those derived from the thoracic wall, trachea, mediastinum, lungs and pleura. They represent a wide variety of lesions including benign and malignant tumors arising from many tissues. The large surface area, 60 to 90 m{sup 2} in man, represented by the respiratory epithelium and associated thoracic structures are ideal targets for carcinogens carried by inspired air. The topic of discussion in this report is the epidemiology, etiology, and mechanisms of spontaneous intrathoracic neoplasia in animals and man. Much of what we know or suspect about thoracic neoplasia in animals has been extrapolated from experimentally-induced neoplasms.

  16. [Pedophilia: etiology, diagnostics and therapy].

    PubMed

    Fromberger, P; Jordan, K; Müller, J L

    2013-09-01

    Child sexual abuse is one of the most destructive events for healthy child development. Following psychiatric classification systems, pedophilia must be distinguished from child sexual abuse. Approximately only one half of all child abusers fulfill the diagnostic criteria for pedophilia which is defined as a persistent or dominating sexual preference for prepubescent children characterized by persistent thoughts, fantasies, urges, sexual arousal or behavior. This article describes the diagnostic criteria and potential differential diagnoses as well as epidemiological and etiological findings. From an etiological point of view multifactorial mechanisms are currently considered to be responsible especially genetic factors, learning theoretical and neurobiological factors. Psychotherapeutic and pharmaceutical treatment options will be discussed. According to the current state of knowledge cognitive-behavioral psychotherapy is the method of choice in the treatment of pedophilia and has demonstrated positive treatment effects in meta-analyses regarding relapse prevention. Medicinal treatment of pedophilia is only indicated for severe forms of pedophilia. Important aspects of risk management in the treatment of pedophilia and aspects which must be considered in the forensic psychiatric assessment are presented. PMID:23793393

  17. Translational control in cancer etiology.

    PubMed

    Ruggero, Davide

    2013-02-01

    The link between perturbations in translational control and cancer etiology is becoming a primary focus in cancer research. It has now been established that genetic alterations in several components of the translational apparatus underlie spontaneous cancers as well as an entire class of inherited syndromes known as "ribosomopathies" associated with increased cancer susceptibility. These discoveries have illuminated the importance of deregulations in translational control to very specific cellular processes that contribute to cancer etiology. In addition, a growing body of evidence supports the view that deregulation of translational control is a common mechanism by which diverse oncogenic pathways promote cellular transformation and tumor development. Indeed, activation of these key oncogenic pathways induces rapid and dramatic translational reprogramming both by increasing overall protein synthesis and by modulating specific mRNA networks. These translational changes promote cellular transformation, impacting almost every phase of tumor development. This paradigm represents a new frontier in the multihit model of cancer formation and offers significant promise for innovative cancer therapies. Current research, in conjunction with cutting edge technologies, will further enable us to explore novel mechanisms of translational control, functionally identify translationally controlled mRNA groups, and unravel their impact on cellular transformation and tumorigenesis. PMID:22767671

  18. Translational Control in Cancer Etiology

    PubMed Central

    Ruggero, Davide

    2013-01-01

    The link between perturbations in translational control and cancer etiology is becoming a primary focus in cancer research. It has now been established that genetic alterations in several components of the translational apparatus underlie spontaneous cancers as well as an entire class of inherited syndromes known as “ribosomopathies” associated with increased cancer susceptibility. These discoveries have illuminated the importance of deregulations in translational control to very specific cellular processes that contribute to cancer etiology. In addition, a growing body of evidence supports the view that deregulation of translational control is a common mechanism by which diverse oncogenic pathways promote cellular transformation and tumor development. Indeed, activation of these key oncogenic pathways induces rapid and dramatic translational reprogramming both by increasing overall protein synthesis and by modulating specific mRNA networks. These translational changes promote cellular transformation, impacting almost every phase of tumor development. This paradigm represents a new frontier in the multihit model of cancer formation and offers significant promise for innovative cancer therapies. Current research, in conjunction with cutting edge technologies, will further enable us to explore novel mechanisms of translational control, functionally identify translationally controlled mRNA groups, and unravel their impact on cellular transformation and tumorigenesis. PMID:22767671

  19. The role of respiratory viruses in the etiology of bacterial pneumonia

    PubMed Central

    Lee, Kyu Han; Gordon, Aubree; Foxman, Betsy

    2016-01-01

    Pneumonia is the leading cause of death among children less than 5 years old worldwide. A wide range of viral, bacterial and fungal agents can cause pneumonia: although viruses are the most common etiologic agent, the severity of clinical symptoms associated with bacterial pneumonia and increasing antibiotic resistance makes bacterial pneumonia a major public health concern. Bacterial pneumonia can follow upper respiratory viral infection and complicate lower respiratory viral infection. Secondary bacterial pneumonia is a major cause of influenza-related deaths. In this review, we evaluate the following hypotheses: (i) respiratory viruses influence the etiology of pneumonia by altering bacterial community structure in the upper respiratory tract (URT) and (ii) respiratory viruses promote or inhibit colonization of the lower respiratory tract (LRT) by certain bacterial species residing in the URT. We conducted a systematic review of the literature to examine temporal associations between respiratory viruses and bacteria and a targeted review to identify potential mechanisms of interactions. We conclude that viruses both alter the bacterial community in the URT and promote bacterial colonization of the LRT. However, it is uncertain whether changes in the URT bacterial community play a substantial role in pneumonia etiology. The exception is Streptococcus pneumoniae where a strong link between viral co-infection, increased carriage and pneumococcal pneumonia has been established. PMID:26884414

  20. The role of respiratory viruses in the etiology of bacterial pneumonia: An ecological perspective.

    PubMed

    Lee, Kyu Han; Gordon, Aubree; Foxman, Betsy

    2016-01-01

    Pneumonia is the leading cause of death among children less than 5 years old worldwide. A wide range of viral, bacterial and fungal agents can cause pneumonia: although viruses are the most common etiologic agent, the severity of clinical symptoms associated with bacterial pneumonia and increasing antibiotic resistance makes bacterial pneumonia a major public health concern. Bacterial pneumonia can follow upper respiratory viral infection and complicate lower respiratory viral infection. Secondary bacterial pneumonia is a major cause of influenza-related deaths. In this review, we evaluate the following hypotheses: (i) respiratory viruses influence the etiology of pneumonia by altering bacterial community structure in the upper respiratory tract (URT) and (ii) respiratory viruses promote or inhibit colonization of the lower respiratory tract (LRT) by certain bacterial species residing in the URT. We conducted a systematic review of the literature to examine temporal associations between respiratory viruses and bacteria and a targeted review to identify potential mechanisms of interactions. We conclude that viruses both alter the bacterial community in the URT and promote bacterial colonization of the LRT. However, it is uncertain whether changes in the URT bacterial community play a substantial role in pneumonia etiology. The exception is Streptococcus pneumoniae where a strong link between viral co-infection, increased carriage and pneumococcal pneumonia has been established. PMID:26884414

  1. Mapping Enterovirus A71 Antigenic Determinants from Viral Evolution

    PubMed Central

    Huang, Sheng-Wen; Tai, Ching-Hui; Fonville, Judith M.; Lin, Chin-Hui; Wang, Shih-Min; Liu, Ching-Chung; Su, Ih-Jen

    2015-01-01

    ABSTRACT Human enterovirus A71 (EV-A71) belongs to the Enterovirus A species in the Picornaviridae family. Several vaccines against EV-A71, a disease causing severe neurological complications or even death, are currently under development and being tested in clinical trials, and preventative vaccination programs are expected to start soon. To characterize the potential for antigenic change of EV-A71, we compared the sequences of two antigenically diverse genotype B4 and B5 strains of EV-A71 and identified substitutions at residues 98, 145, and 164 in the VP1 capsid protein as antigenic determinants. To examine the effects of these three substitutions on antigenicity, we constructed a series of recombinant viruses containing different mutation combinations at these three residues with a reverse genetics system and then investigated the molecular basis of antigenic changes with antigenic cartography. We found that a novel EV-A71 mutant, containing lysine, glutamine, and glutamic acid at the respective residues 98, 145, and 164 in the VP1 capsid protein, exhibited neutralization reduction against patients' antisera and substantially increased virus binding ability to human cells. These observations indicated that this low-neutralization-reactive EV-A71 VP1-98K/145Q/164E mutant potentially increases viral binding ability and that surveillance studies should look out for these mutants, which could compromise vaccine efficacy. IMPORTANCE Emerging and reemerging EV-A71 viruses can cause severe neurological etiology, primarily affecting children, especially around Asia-Pacific countries. We identified a set of mutations in EV-A71 that both reduced neutralization activity against humoral immunity in antisera of patients and healthy adults and greatly increased the viral binding ability to cells. These findings provide important insights for EV-A71 antigenic determinants and emphasize the importance of continuous surveillance, especially after EV-A71 vaccination programs

  2. Etiological characteristics of abusive husbands.

    PubMed

    Hurlbert, D F; Whittaker, K E; Munoz, C J

    1991-12-01

    This study compared abusive husbands with nonabusive, marital discordant husbands using six measures to ascertain certain etiological characteristics of abusers. Both groups completed the Jenkins Activity Survey for measuring type A behavior, the Short Michigan Alcoholism Screening Test, the Index of Self-Esteem, the Spence-Helmrich Attitudes Toward Women Scale, the Index of Marital Satisfaction, and a simple rating scale to access their perceptions of their wives' physical attractiveness. As predicted, abusers evidence significantly higher type A behaviors, higher problem drinking behaviors, more rigid attitudes toward women, lower marital satisfaction, and rated their wives as less attractive than did nonabusers. Inconsistent with the literature, however, no significant differences were discovered between the self-esteem of abusers and nonabusers. PMID:1780068

  3. Noise Injury: Etiology and Prevention

    PubMed Central

    Lees, R. E. M.

    1982-01-01

    Exposure to noise might be responsible for a wide and varied spectrum of physical and mental morbidity, although many of the claims of cause and effect relationship are controversial and unproven. The etiological relationship between noise and high frequency hearing loss is, however, well documented. While noise-induced hearing loss is considered to be primarily an occupational problem, current leisure time activities have created the potential for it to become more common in the community at large. Once developed, this hearing loss is permanent and cannot be influenced by therapy. Noise-induced hearing loss is almost completely preventable and the family physician has an important responsibility for primary and secondary prevention, whether the noise source is in the workplace or in some other location. PMID:21286519

  4. [Microbiological diagnosis of viral respiratory infections].

    PubMed

    Eiros, José M; Ortiz de Lejarazu, Raúl; Tenorio, Alberto; Casas, Inmaculada; Pozo, Francisco; Ruiz, Guillermo; Pérez-Breña, Pilar

    2009-03-01

    Acute respiratory infection is the most common disease occurring over a person's lifetime, with etiological variations determined mainly by age, environmental circumstances, the healthcare setting, and the underlying pathology. More than 200 different viruses distributed in six viral families have been implicated in the pathogenesis of respiratory tract infection. These facts are generating an increasing diagnostic demand that should be incorporated into the healthcare setting without delay. To meet this demand, the Spanish Society of Infectious Diseases and Clinical Microbiology has updated its Standard Procedure for the microbiological diagnosis of viral respiratory infection. This document contains an update primarily of infections caused by influenza viruses, and secondarily, infections due to other conventional and emerging respiratory viruses. In all cases, the methods for direct virological diagnosis (cell culture, and detection of antigens and nucleic acid) are reviewed, with special reference to techniques for molecular detection and genetic characterization. PMID:19306718

  5. Clues to the Etiology of Bile Duct Injury in Biliary Atresia

    PubMed Central

    Mack, Cara L.; Feldman, Amy G.; Sokol, Ronald J.

    2013-01-01

    Biliary atresia (BA) is an infantile obstructive cholangiopathy of unknown etiology with suboptimal therapy, which is responsible for 40 to 50% of all pediatric liver transplants. Although the etiology of bile duct injury in BA in unknown, it is postulated that a pre- or perinatal viral infection initiates cholangiocyte apoptosis and release of antigens that trigger a Th1 immune response that leads to further bile duct injury, inflammation, and obstructive fibrosis. Humoral immunity and activation of the innate immune system may also play key roles in this process. Moreover, recent investigations from the murine BA model and human data suggest that regulatory T cells and genetic susceptibility factors may orchestrate autoimmune mechanisms. What controls the coordination of these events, why the disease only occurs in the first few months of life, and why a minority of infants with perinatal viral infections develop BA are remaining questions to be answered. PMID:23397531

  6. Etiology of primary spontaneous pneumothorax.

    PubMed

    Lyra, Roberto de Menezes

    2016-01-01

    With the advent of HRCT, primary spontaneous pneumothorax has come to be better understood and managed, because its etiology can now be identified in most cases. Primary spontaneous pneumothorax is mainly caused by the rupture of a small subpleural emphysematous vesicle (designated a bleb) or of a subpleural paraseptal emphysematous lesion (designated a bulla). The aim of this pictorial essay was to improve the understanding of primary spontaneous pneumothorax and to propose a description of the major anatomical lesions found during surgery. RESUMO Com o advento da TCAR, o pneumotórax espontâneo primário passou a ser mais bem entendido e conduzido, pois sua etiologia pode ser atualmente identificada na maioria dos casos. O pneumotórax espontâneo primário tem como principal causa a rotura de uma pequena vesícula enfisematosa subpleural, denominada bleb ou de uma lesão enfisematosa parasseptal subpleural, denominada bulla. O objetivo deste ensaio pictórico foi melhorar o entendimento do pneumotórax espontâneo primário e propor uma descrição das principais lesões anatômicas encontradas durante a cirurgia. PMID:27383937

  7. [Neuropediatrics: epidemiological features and etiologies at the Dakar neurology service].

    PubMed

    Ndiaye, M; Sene-Diouf, F; Diop, A G; Ndao, A K; Ndiaye, M M; Ndiaye, I P

    1999-01-01

    Child neurology is a relatively young speciality of neurosciences which is at the frontier of Neurology and Paediatrics. Its development has been impulsed by the diagnosis techniques such as Neurobiology, Genetics, Neuroimaging and pedo-psychology. We conducted a retrospective survey among the in-patients from January 1980 to December 1997 in the service of Neurology of the University Hospital. Have been included children ranged from 0 to 15 years old without any racial, sexual or origin distinctive. In Neurology Department, children of 0 to 15 years old represent 10.06% of the in-patients received from 1980 to 1997. The mortality rate was 9.23%. The diseases are dominated by epilepsy and infantile encephalopathies with 31.02%, infectious diseases with 19.36% represented by tuberculosis, other bacterial, viral and parasitical etiologies, tumors with 10.36%, vascular pathology and degenerative disorders. PMID:11957278

  8. Perspectives on retroviruses and the etiologic agent of AIDS.

    PubMed Central

    Hsiung, G. D.

    1987-01-01

    In 1911, the first retrovirus was described: the Rous sarcoma virus, an avian retrovirus. Forty years later the murine leukemic virus, a mouse retrovirus, was reported. Although many other retroviruses from non-primate species were identified during the 1960s, the first primate retrovirus was not recognized until it was isolated from a monkey tumor in 1970. The search for human retroviruses in human leukemic cells remained unsuccessful at that time. Facilitated by the discovery of T-cell growth factor, a substance used for the propagation of human leukocytes in cultures, the first human retrovirus was discovered in 1980. Soon thereafter, in 1983, another human retrovirus, human immunodeficiency virus (HIV), was reported and implicated as the etiologic agent of AIDS. The isolation and identification of HIV has stimulated much interest in the study of human retroviruses and the control of this new viral disease. Images FIG. 2 FIG. 3 PMID:2829449

  9. Multicenter Evaluation of the BioFire FilmArray Gastrointestinal Panel for Etiologic Diagnosis of Infectious Gastroenteritis

    PubMed Central

    Leber, Amy; Chapin, Kimberle; Fey, Paul D.; Bankowski, Matthew J.; Jones, Matthew K.; Rogatcheva, Margarita; Kanack, Kristen J.; Bourzac, Kevin M.

    2015-01-01

    The appropriate treatment and control of infectious gastroenteritis depend on the ability to rapidly detect the wide range of etiologic agents associated with the disease. Clinical laboratories currently utilize an array of different methodologies to test for bacterial, parasitic, and viral causes of gastroenteritis, a strategy that suffers from poor sensitivity, potentially long turnaround times, and complicated ordering practices and workflows. Additionally, there are limited or no testing methods routinely available for most diarrheagenic Escherichia coli strains, astroviruses, and sapoviruses. This study assessed the performance of the FilmArray Gastrointestinal (GI) Panel for the simultaneous detection of 22 different enteric pathogens directly from stool specimens: Campylobacter spp., Clostridium difficile (toxin A/B), Plesiomonas shigelloides, Salmonella spp., Vibrio spp., Vibrio cholerae, Yersinia enterocolitica, enteroaggregative E. coli, enteropathogenic E. coli, enterotoxigenic E. coli, Shiga-like toxin-producing E. coli (stx1 and stx2) (including specific detection of E. coli O157), Shigella spp./enteroinvasive E. coli, Cryptosporidium spp., Cyclospora cayetanensis, Entamoeba histolytica, Giardia lamblia, adenovirus F 40/41, astrovirus, norovirus GI/GII, rotavirus A, and sapovirus. Prospectively collected stool specimens (n = 1,556) were evaluated using the BioFire FilmArray GI Panel and tested with conventional stool culture and molecular methods for comparison. The FilmArray GI Panel sensitivity was 100% for 12/22 targets and ≥94.5% for an additional 7/22 targets. For the remaining three targets, sensitivity could not be calculated due to the low prevalences in this study. The FilmArray GI Panel specificity was ≥97.1% for all panel targets. The FilmArray GI Panel provides a comprehensive, rapid, and streamlined alternative to conventional methods for the etiologic diagnosis of infectious gastroenteritis in the laboratory setting. The potential

  10. Multicenter evaluation of the BioFire FilmArray gastrointestinal panel for etiologic diagnosis of infectious gastroenteritis.

    PubMed

    Buss, Sarah N; Leber, Amy; Chapin, Kimberle; Fey, Paul D; Bankowski, Matthew J; Jones, Matthew K; Rogatcheva, Margarita; Kanack, Kristen J; Bourzac, Kevin M

    2015-03-01

    The appropriate treatment and control of infectious gastroenteritis depend on the ability to rapidly detect the wide range of etiologic agents associated with the disease. Clinical laboratories currently utilize an array of different methodologies to test for bacterial, parasitic, and viral causes of gastroenteritis, a strategy that suffers from poor sensitivity, potentially long turnaround times, and complicated ordering practices and workflows. Additionally, there are limited or no testing methods routinely available for most diarrheagenic Escherichia coli strains, astroviruses, and sapoviruses. This study assessed the performance of the FilmArray Gastrointestinal (GI) Panel for the simultaneous detection of 22 different enteric pathogens directly from stool specimens: Campylobacter spp., Clostridium difficile (toxin A/B), Plesiomonas shigelloides, Salmonella spp., Vibrio spp., Vibrio cholerae, Yersinia enterocolitica, enteroaggregative E. coli, enteropathogenic E. coli, enterotoxigenic E. coli, Shiga-like toxin-producing E. coli (stx1 and stx2) (including specific detection of E. coli O157), Shigella spp./enteroinvasive E. coli, Cryptosporidium spp., Cyclospora cayetanensis, Entamoeba histolytica, Giardia lamblia, adenovirus F 40/41, astrovirus, norovirus GI/GII, rotavirus A, and sapovirus. Prospectively collected stool specimens (n = 1,556) were evaluated using the BioFire FilmArray GI Panel and tested with conventional stool culture and molecular methods for comparison. The FilmArray GI Panel sensitivity was 100% for 12/22 targets and ≥94.5% for an additional 7/22 targets. For the remaining three targets, sensitivity could not be calculated due to the low prevalences in this study. The FilmArray GI Panel specificity was ≥97.1% for all panel targets. The FilmArray GI Panel provides a comprehensive, rapid, and streamlined alternative to conventional methods for the etiologic diagnosis of infectious gastroenteritis in the laboratory setting. The potential

  11. [Clinical aspects and diagnosis of viral hepatitis].

    PubMed

    Vince, Adriana

    2003-01-01

    Viral hepatitides are common diseases of modern man in both industrialized and developing countries, with a varying prevalence of particular types and mode of transmission. In current medicine, viral hepatitides are classified in the A-E nomenclature, differentiating viruses that can be etiologically defined with certainty on the basis of serum markers and hepatitides exhibiting all clinical and laboratory characteristics of viral hepatitis but of as yet nondemonstrable causative agents, classified in the non-A, non-E hepatitis group. Two issues are of high relevance in the pathogenesis of viral hepatitides: route of transmission (fecal-oral or parenteral) and basic mechanism of hepatocyte lesion. Although all hepatitis viruses replicate within the hepatocyte, the exact mechanism of hepatocyte necrosis has not yet been fully elucidated, i.e. direct cytotoxicity or hepatoprogressive immune response mediated primarily by the specific cytotoxic CD8 lymphocytes. Depending on the site of entry, the virus replicates in the adjacent lymphatic tissue for some time, followed by primary viremia, virus replication in the lymphoreticular organs (lymph nodes, liver, spleen), and eventual entry in the target cells--hepatocytes, accompanied by a varying grade of necrosis and inflammatory reaction. The clinical and laboratory signs of the disease correspond to the degree of liver necrosis and are not specific for particular types of viral hepatitis. The most frequent symptoms common to all types of viral hepatitis of moderate severity include elevated body temperature persisting for days, fatigue, gradual loss of appetite, nausea, dull pain and discomfort on DRL, vomiting, multiple loose stools, dark urine, jaundice of the skin and mucosa, and light stools. Generally, the ultimate outcome of the disease is elimination of the virus and complete recovery, however, a fulminant course with lethal outcome or transition to chronic disease may also occur, making viral hepatitides a major

  12. Ball Python Nidovirus: a Candidate Etiologic Agent for Severe Respiratory Disease in Python regius

    PubMed Central

    Stenglein, Mark D.; Jacobson, Elliott R.; Wozniak, Edward J.; Wellehan, James F. X.; Kincaid, Anne; Gordon, Marcus; Porter, Brian F.; Baumgartner, Wes; Stahl, Scott; Kelley, Karen; Towner, Jonathan S.

    2014-01-01

    ABSTRACT A severe, sometimes fatal respiratory disease has been observed in captive ball pythons (Python regius) since the late 1990s. In order to better understand this disease and its etiology, we collected case and control samples and performed pathological and diagnostic analyses. Electron micrographs revealed filamentous virus-like particles in lung epithelial cells of sick animals. Diagnostic testing for known pathogens did not identify an etiologic agent, so unbiased metagenomic sequencing was performed. Abundant nidovirus-like sequences were identified in cases and were used to assemble the genome of a previously unknown virus in the order Nidovirales. The nidoviruses, which were not previously known to infect nonavian reptiles, are a diverse order that includes important human and veterinary pathogens. The presence of the viral RNA was confirmed in all diseased animals (n = 8) but was not detected in healthy pythons or other snakes (n = 57). Viral RNA levels were generally highest in the lung and other respiratory tract tissues. The 33.5-kb viral genome is the largest RNA genome yet described and shares canonical characteristics with other nidovirus genomes, although several features distinguish this from related viruses. This virus, which we named ball python nidovirus (BPNV), will likely establish a new genus in Torovirinae subfamily. The identification of a novel nidovirus in reptiles contributes to our understanding of the biology and evolution of related viruses, and its association with lung disease in pythons is a promising step toward elucidating an etiology for this long-standing veterinary disease. PMID:25205093

  13. Exosomes in Viral Disease.

    PubMed

    Anderson, Monique R; Kashanchi, Fatah; Jacobson, Steven

    2016-07-01

    Viruses have evolved many mechanisms by which to evade and subvert the immune system to ensure survival and persistence. However, for each method undertaken by the immune system for pathogen removal, there is a counteracting mechanism utilized by pathogens. The new and emerging role of microvesicles in immune intercellular communication and function is no different. Viruses across many different families have evolved to insert viral components in exosomes, a subtype of microvesicle, with many varying downstream effects. When assessed cumulatively, viral antigens in exosomes increase persistence through cloaking viral genomes, decoying the immune system, and even by increasing viral infection in uninfected cells. Exosomes therefore represent a source of viral antigen that can be used as a biomarker for disease and targeted for therapy in the control and eradication of these disorders. With the rise in the persistence of new and reemerging viruses like Ebola and Zika, exploring the role of exosomes become more important than ever. PMID:27324390

  14. HIV-1 viral diversity and its implications for viral load testing: review of current platforms.

    PubMed

    Luft, LeeAnne M; Gill, M John; Church, Deirdre L

    2011-10-01

    The 2008 Recommendations for care of the International AIDS Society reaffirmed the importance of both accurate and sensitive viral load assessment, and by necessity, access to viral load assays. HIV-1 viral load testing is considered essential when initiating antiretroviral therapy (ART), when monitoring ART response, and when considering switching ART regimens. The demand for accurate, reproducible, and cost-effective viral load assays is therefore a global issue. Although the North American and Western European experience has historically been with HIV-1 group M subtype B virus, this paradigm is changing rapidly as migrants and refugees from developing countries with non-B subtype infections often now present for care in the developed world, and travelers to developing countries acquire non-B subtype infection abroad and present for care at home. Awareness of any clinical or laboratory differences between the common HIV-1 group M subtype B and the newer HIV-1 strains being seen in practice is therefore increasingly important. This review of current HIV-1 viral load testing is focused on the potential value of a standardized genotype assignment for HIV-1 viral subtypes, regular monitoring of the performance of available commercial HIV viral load assays on emerging non-B HIV subtypes, circulating recombinant forms (CRFs) and unique recombinant forms (URFs), and a discussion of the implications for resource-limited settings. PMID:21767972

  15. Viruses and viral proteins

    PubMed Central

    Verdaguer, Nuria; Ferrero, Diego; Murthy, Mathur R. N.

    2014-01-01

    For more than 30 years X-ray crystallography has been by far the most powerful approach for determining the structures of viruses and viral proteins at atomic resolution. The information provided by these structures, which covers many important aspects of the viral life cycle such as cell-receptor recognition, viral entry, nucleic acid transfer and genome replication, has extensively enriched our vision of the virus world. Many of the structures available correspond to potential targets for antiviral drugs against important human pathogens. This article provides an overview of the current knowledge of different structural aspects of the above-mentioned processes. PMID:25485129

  16. HIV and Viral Hepatitis

    MedlinePlus

    ... prevalent among blacks as among whites. Viral Hepatitis Transmission People can be infected with the three most ... risk for HAV. • • New data suggest that sexual transmission of HCV among MSM with HIV occurs more ...

  17. VIRAL INFECTIONS DURING PREGNANCY

    PubMed Central

    Silasi, Michelle; Cardenas, Ingrid; Racicot, Karen; Kwon, Ja-Young; Aldo, Paula; Mor, Gil

    2015-01-01

    Viral infections during pregnancy have long been considered benign conditions with a few notable exceptions, such as herpes virus. The recent Ebola outbreak and other viral epidemics and pandemics show how pregnant women suffer worse outcomes (such as preterm labor and adverse fetal outcomes) than the general population and non-pregnant women. New knowledge about the ways the maternal-fetal interface and placenta interact with the maternal immune system may explain these findings. Once thought to be “immunosuppressed”, the pregnant woman actually undergoes an immunological transformation, where the immune system is necessary to promote and support the pregnancy and growing fetus. When this protection is breached, as in a viral infection, this security is weakened and infection with other microorganisms can then propagate and lead to outcomes, such as preterm labor. In this manuscript, we review the major viral infections relevant to pregnancy, and offer potential mechanisms for the associated adverse pregnancy outcomes. PMID:25582523

  18. Viral Hemorrhagic Fevers

    MedlinePlus

    ... Related Links About VSPB (Viral Special Pathogens Branch) File Formats Help: How do I view different file formats (PDF, DOC, PPT, MPEG) on this site? Adobe PDF file Microsoft PowerPoint file Microsoft Word file Microsoft Excel ...

  19. Viral quasispecies complexity measures.

    PubMed

    Gregori, Josep; Perales, Celia; Rodriguez-Frias, Francisco; Esteban, Juan I; Quer, Josep; Domingo, Esteban

    2016-06-01

    Mutant spectrum dynamics (changes in the related mutants that compose viral populations) has a decisive impact on virus behavior. The several platforms of next generation sequencing (NGS) to study viral quasispecies offer a magnifying glass to study viral quasispecies complexity. Several parameters are available to quantify the complexity of mutant spectra, but they have limitations. Here we critically evaluate the information provided by several population diversity indices, and we propose the introduction of some new ones used in ecology. In particular we make a distinction between incidence, abundance and function measures of viral quasispecies composition. We suggest a multidimensional approach (complementary information contributed by adequately chosen indices), propose some guidelines, and illustrate the use of indices with a simple example. We apply the indices to three clinical samples of hepatitis C virus that display different population heterogeneity. Areas of virus biology in which population complexity plays a role are discussed. PMID:27060566

  20. Viral miRNAs.

    PubMed

    Plaisance-Bonstaff, Karlie; Renne, Rolf

    2011-01-01

    Since 2004, more than 200 microRNAs (miRNAs) have been discovered in double-stranded DNA viruses, mainly herpesviruses and polyomaviruses (Nucleic Acids Res 32:D109-D111, 2004). miRNAs are short 22  ±  3 nt RNA molecules that posttranscriptionally regulate gene expression by binding to 3'-untranslated regions (3'UTR) of target mRNAs, thereby inducing translational silencing and/or transcript degradation (Nature 431:350-355, 2004; Cell 116:281-297, 2004). Since miRNAs require only limited complementarity for binding, miRNA targets are difficult to determine (Mol Cell 27:91-105, 2007). To date, targets have only been experimentally verified for relatively few viral miRNAs, which either target viral or host cellular gene expression: For example, SV40 and related polyomaviruses encode miRNAs which target viral large T antigen expression (Nature 435:682-686, 2005; J Virol 79:13094-13104, 2005; Virology 383:183-187, 2009; J Virol 82:9823-9828, 2008) and miRNAs of α-, β-, and γ-herpesviruses have been implicated in regulating the transition from latent to lytic gene expression, a key step in the herpesvirus life cycle. Viral miRNAs have also been shown to target various host cellular genes. Although this field is just beginning to unravel the multiple roles of viral miRNA in biology and pathogenesis, the current data strongly suggest that virally encoded miRNAs are able to regulate fundamental biological processes such as immune recognition, promotion of cell survival, angiogenesis, proliferation, and cell differentiation. This chapter aims to summarize our current knowledge of viral miRNAs, their targets and function, and the challenges lying ahead to decipher their role in viral biology, pathogenesis, and for γ-herepsvirus-encoded miRNAs, potentially tumorigenesis. PMID:21431678

  1. Immigration and viral hepatitis.

    PubMed

    Sharma, Suraj; Carballo, Manuel; Feld, Jordan J; Janssen, Harry L A

    2015-08-01

    WHO estimates reveal that the global prevalence of viral hepatitis may be as high as 500 million, with an annual mortality rate of up to 1.3 million individuals. The majority of this global burden of disease is borne by nations of the developing world with high rates of vertical and iatrogenic transmission of HBV and HCV, as well as poor access to healthcare. In 2013, 3.2% of the global population (231 million individuals) migrated into a new host nation. Migrants predominantly originate from the developing countries of the south, into the developed economies of North America and Western Europe. This mass migration of individuals from areas of high-prevalence of viral hepatitis poses a unique challenge to the healthcare systems of the host nations. Due to a lack of universal standards for screening, vaccination and treatment of viral hepatitis, the burden of chronic liver disease and hepatocellular carcinoma continues to increase among migrant populations globally. Efforts to increase case identification and treatment among migrants have largely been limited to small outreach programs in urban centers, such that the majority of migrants with viral hepatitis continue to remain unaware of their infection. This review summarizes the data on prevalence of viral hepatitis and burden of chronic liver disease among migrants, current standards for screening and treatment of immigrants and refugees, and efforts to improve the identification and treatment of viral hepatitis among migrants. PMID:25962882

  2. Viral suppressors of RNA-based viral immunity: Host targets

    PubMed Central

    Wu, Qingfa; Wang, Xianbing

    2010-01-01

    Discovery of diverse plant and animal viral proteins as suppressors of RNA silencing has provided strong support for an RNA-based viral immunity (RVI), which is now known to specifically destroy viral RNAs by RNA interference in fungi, plants and invertebrates. Here we review several recent studies that have revealed new mechanistic insights into plant and insect viral suppressors of RVI or suggested a role for RNA silencing suppression during mammalian viral infection. PMID:20638637

  3. Protection from persistent infection with a bovine viral diarrhea virus (BVDV) type 1b strain by a modified-live vaccine containing BVDV types 1a and 2, infectious bovine rhinotracheitis virus, parainfluenza 3 virus and bovine respiratory syncytial virus.

    PubMed

    Xue, Wenzhi; Mattick, Debra; Smith, Linda

    2011-06-24

    Recent studies showed that BVDV-1b subgenotype is dominant in North and South American field BVDV isolates. However, nearly all commercially available BVDV-1 vaccines contain BVDV-1a strains. In order to study the efficacy of BVDV-1a vaccine against BVDV-1b infection, this study was designed to evaluate a modified-live vaccine (MLV) containing BVDV-1a and BVDV-2 strains for its efficacy in prevention of persistent infection of fetuses against BVDV-1b strain, when the heifers were vaccinated prior to breeding. Heifers were vaccinated subcutaneously with a single dose of the MLV and bred four weeks after vaccination. The pregnant heifers were challenged with a non-cytopathic BVDV-1b strain at approximately 80 days of gestation. Vaccinated heifers were protected from clinical disease and viremia caused by the BVDV-1b virus. At approximately 155 days of gestation, the fetuses were harvested and tissue samples of thymus, lungs, spleen, kidney and intestines were collected for virus isolation. BVDV was isolated from 100% of the fetuses in the non-vaccinated control group, and from only one fetus (4.3%) from the vaccinated group. Results demonstrated that the MLV containing BVDV-1a and BVDV-2 strains provided 96% protection from fetal persistent infection caused by the BVDV-1b strain. PMID:21596076

  4. Emmprin and KSHV: new partners in viral cancer pathogenesis

    PubMed Central

    Dai, Lu; Bai, Lihua; Lu, Ying; Xu, Zengguang; Reiss, Krys; Valle, Luis Del; Kaleeba, Johnan; Toole, Bryan P.; Parsons, Chris; Qin, Zhiqiang

    2013-01-01

    Emmprin (CD147; basigin) is a multifunctional glycoprotein expressed at higher levels by cancer cells and stromal cells in the tumor microenvironment. Through direct effects within tumor cells and promotion of tumor-stroma interactions, emmprin participates in induction of tumor cell invasiveness, angiogenesis, metastasis and chemoresistance. Although its contribution to cancer progression has been widely studied, the role of emmprin in viral oncogenesis still remains largely unclear, and only a small body of available literature implicates emmprin-associated mechanisms in viral pathogenesis and tumorigenesis. We summarize these data in this review, focusing on the role of emmprin in pathogenesis associated with the Kaposi sarcoma-associated herpesvirus (KSHV), a common etiology for cancers arising in the setting of immune suppression. We also discuss future directions for mechanistic studies exploring roles for emmprin in viral cancer pathogenesis. PMID:23743354

  5. Concepts in viral pathogenesis II

    SciTech Connect

    Notkins, A.L.; Oldstone, M.B.A.

    1986-01-01

    This paper contains papers divided among 10 sections. The section titles are: Viral Structure and Function; Viral Constructs; Oncogenes, Transfection, and Differentiation; Viral Tropism and Entry into Cells; Immune Recognition of Viruses; Evolving Concepts in Viral Pathogenesis Illustrated by Selected Plant and Animal Models; Evolving Concepts in Viral Pathogenesis Illustrated by Selected Diseases in Humans; New Trends in Diagnosis and Epidemiology; and Vaccines and Antiviral Therapy.

  6. The Pneumonia Etiology Research for Child Health Project: A 21st Century Childhood Pneumonia Etiology Study

    PubMed Central

    O’Brien, Katherine L.; Deloria-Knoll, Maria; Murdoch, David R.; Feikin, Daniel R.; DeLuca, Andrea N.; Driscoll, Amanda J.; Baggett, Henry C.; Brooks, W. Abdullah; Howie, Stephen R. C.; Kotloff, Karen L.; Madhi, Shabir A.; Maloney, Susan A.; Sow, Samba; Thea, Donald M.; Scott, J. Anthony

    2012-01-01

    The Pneumonia Etiology Research for Child Health (PERCH) project is a 7-country, standardized, comprehensive evaluation of the etiologic agents causing severe pneumonia in children from developing countries. During previous etiology studies, between one-quarter and one-third of patients failed to yield an obvious etiology; PERCH will employ and evaluate previously unavailable innovative, more sensitive diagnostic techniques. Innovative and rigorous epidemiologic and analytic methods will be used to establish the causal association between presence of potential pathogens and pneumonia. By strategic selection of study sites that are broadly representative of regions with the greatest burden of childhood pneumonia, PERCH aims to provide data that reflect the epidemiologic situation in developing countries in 2015, using pneumococcal and Haemophilus influenzae type b vaccines. PERCH will also address differences in host, environmental, and/or geographic factors that might determine pneumonia etiology and, by preserving specimens, will generate a resource for future research and pathogen discovery. PMID:22403238

  7. Micropenis: Etiology, Diagnosis and Treatment Approaches

    PubMed Central

    Hatipoğlu, Nihal; Kurtoğlu, Selim

    2013-01-01

    Micropenis is a medical diagnosis based on correct measurement of length. If stretched penile length is below the value corresponding to - 2.5 standard deviation of the mean in a patient with normal internal and external male genitalia, a diagnosis of micropenis is considered. Micropenis can be caused by a variety of factors including structural or hormonal defects of the hypothalamic-pituitary-gonadal axis. It can also be a component of a number of congenital syndromes. For the etiological evaluation, endocrinologic tests are important. This article reviews the etiology, diagnosis, treatment and management of micropenis. Conflict of interest:None declared. PMID:24379029

  8. Viral hepatitis: Indian scenario.

    PubMed

    Satsangi, Sandeep; Chawla, Yogesh K

    2016-07-01

    Viral hepatitis is a cause for major health care burden in India and is now equated as a threat comparable to the "big three" communicable diseases - HIV/AIDS, malaria and tuberculosis. Hepatitis A virus and Hepatitis E virus are predominantly enterically transmitted pathogens and are responsible to cause both sporadic infections and epidemics of acute viral hepatitis. Hepatitis B virus and Hepatitis C virus are predominantly spread via parenteral route and are notorious to cause chronic hepatitis which can lead to grave complications including cirrhosis of liver and hepatocellular carcinoma. Around 400 million people all over the world suffer from chronic hepatitis and the Asia-Pacific region constitutes the epicentre of this epidemic. The present article would aim to cover the basic virologic aspects of these viruses and highlight the present scenario of viral hepatitis in India. PMID:27546957

  9. Modeling Viral Capsid Assembly

    PubMed Central

    2014-01-01

    I present a review of the theoretical and computational methodologies that have been used to model the assembly of viral capsids. I discuss the capabilities and limitations of approaches ranging from equilibrium continuum theories to molecular dynamics simulations, and I give an overview of some of the important conclusions about virus assembly that have resulted from these modeling efforts. Topics include the assembly of empty viral shells, assembly around single-stranded nucleic acids to form viral particles, and assembly around synthetic polymers or charged nanoparticles for nanotechnology or biomedical applications. I present some examples in which modeling efforts have promoted experimental breakthroughs, as well as directions in which the connection between modeling and experiment can be strengthened. PMID:25663722

  10. Latent Herpes Viral Reactivation in Astronauts

    NASA Technical Reports Server (NTRS)

    Pierson, D. L.; Mehta, S. K.; Stowe, R.

    2008-01-01

    Latent viruses are ubiquitous and reactivate during stressful periods with and without symptoms. Latent herpes virus reactivation is used as a tool to predict changes in the immune status in astronauts and to evaluate associated health risks. Methods: Viral DNA was detected by real time polymerase chain reaction in saliva and urine from astronauts before, during and after short and long-duration space flights. Results and Discussion: EpsteinBarr virus (EBV), cytomegalovirus (CMV), and varicella zoster virus (VZV) reactivated, and viral DNA was shed in saliva (EBV and VZV) or urine (CMV). EBV levels in saliva during flight were 10fold higher than baseline levels. Elevations in EBV specific CD8+ T-cells, viral antibody titers, and specific cytokines were consistent with viral reactivation. Intracellular levels of cytokines were reduced in EBVspecific Tcells. CMV, rarely present in urine of healthy individuals, was shed in urine of 27% of astronauts during all phases of spaceflight. VZV, not found in saliva of asymptomatic individuals, was found in saliva of 50% of astronauts during spaceflight and 35 days after flight. VZV recovered from astronaut saliva was found to be live, infectious virus. DNA sequencing demonstrated that the VZV recovered from astronauts was from the common European strain of VZV. Elevation of stress hormones accompanied viral reactivation indicating involvement of the hypothalmic-pituitary-adrenal and sympathetic adrenal-medullary axes in the mechanism of viral reactivation in astronauts. A study of 53 shingles patients found that all shingles patients shed VZV DNA in their saliva and the VZV levels correlated with the severity of the disease. Lower VZV levels in shingles patients were similar to those observed in astronauts. We proposed a rapid, simple, and cost-effective assay to detect VZV in saliva of patients with suspected shingles. Early detection of VZV infection allows early medical intervention.

  11. Porcine epidemic diarrhea virus infection: Etiology, epidemiology, pathogenesis and immunoprophylaxis.

    PubMed

    Jung, Kwonil; Saif, Linda J

    2015-05-01

    Porcine epidemic diarrhea virus (PEDV), a member of the genera Alphacoronavirus in the family Coronaviridae, causes acute diarrhea/vomiting, dehydration and high mortality in seronegative neonatal piglets. For the last three decades, PEDV infection has resulted in significant economic losses in the European and Asian pig industries, but in 2013-2014 the disease was also reported in the US, Canada and Mexico. The PED epidemic in the US, from April 2013 to the present, has led to the loss of more than 10% of the US pig population. The disappearance and re-emergence of epidemic PED indicates that the virus is able to escape from current vaccination protocols, biosecurity and control systems. Endemic PED is a significant problem, which is exacerbated by the emergence (or potential importation) of multiple PEDV variants. Epidemic PEDV strains spread rapidly and cause a high number of pig deaths. These strains are highly enteropathogenic and acutely infect villous epithelial cells of the entire small and large intestines although the jejunum and ileum are the primary sites. PEDV infections cause acute, severe atrophic enteritis accompanied by viremia that leads to profound diarrhea and vomiting, followed by extensive dehydration, which is the major cause of death in nursing piglets. A comprehensive understanding of the pathogenic characteristics of epidemic or endemic PEDV strains is needed to prevent and control the disease in affected regions and to develop an effective vaccine. This review focuses on the etiology, epidemiology, disease mechanisms and pathogenesis as well as immunoprophylaxis against PEDV infection. PMID:25841898

  12. [Viral hepatitis in travellers].

    PubMed

    Abreu, Cândida

    2007-01-01

    Considering the geographical asymmetric distribution of viral hepatitis A, B and E, having a much higher prevalence in the less developed world, travellers from developed countries are exposed to a considerable and often underestimated risk of hepatitis infection. In fact a significant percentage of viral hepatitis occurring in developed countries is travel related. This results from globalization and increased mobility from tourism, international work, humanitarian and religious missions or other travel related activities. Several studies published in Europe and North America shown that more than 50% of reported cases of hepatitis A are travel related. On the other hand frequent outbreaks of hepatitis A and E in specific geographic areas raise the risk of infection in these restricted zones and that should be clearly identified. Selected aspects related with the distribution of hepatitis A, B and E are reviewed, particularly the situation in Portugal according to the published studies, as well as relevant clinical manifestations and differential diagnosis of viral hepatitis. Basic prevention rules considering enteric transmitted hepatitis (hepatitis A and hepatitis E) and parenteral transmitted (hepatitis B) are reviewed as well as hepatitis A and B immunoprophylaxis. Common clinical situations and daily practice "pre travel" advice issues are discussed according to WHO/CDC recommendations and the Portuguese National Vaccination Program. Implications from near future availability of a hepatitis E vaccine, a currently in phase 2 trial, are highlighted. Potential indications for travellers to endemic countries like India, Nepal and some regions of China, where up to 30% of sporadic cases of acute viral hepatitis are caused by hepatitis E virus, are considered. Continued epidemiological surveillance for viral hepatitis is essential to recognize and control possible outbreaks, but also to identify new viral hepatitis agents that may emerge as important global health

  13. Assessing viral taxonomic composition in benthic marine ecosystems: reliability and efficiency of different bioinformatic tools for viral metagenomic analyses

    PubMed Central

    Tangherlini, M.; Dell’Anno, A.; Zeigler Allen, L.; Riccioni, G.; Corinaldesi, C.

    2016-01-01

    In benthic deep-sea ecosystems, which represent the largest biome on Earth, viruses have a recognised key ecological role, but their diversity is still largely unknown. Identifying the taxonomic composition of viruses is crucial for understanding virus-host interactions, their role in food web functioning and evolutionary processes. Here, we compared the performance of various bioinformatic tools (BLAST, MG-RAST, NBC, VMGAP, MetaVir, VIROME) for analysing the viral taxonomic composition in simulated viromes and viral metagenomes from different benthic deep-sea ecosystems. The analyses of simulated viromes indicate that all the BLAST tools, followed by MetaVir and VMGAP, are more reliable in the affiliation of viral sequences and strains. When analysing the environmental viromes, tBLASTx, MetaVir, VMGAP and VIROME showed a similar efficiency of sequence annotation; however, MetaVir and tBLASTx identified a higher number of viral strains. These latter tools also identified a wider range of viral families than the others, providing a wider view of viral taxonomic diversity in benthic deep-sea ecosystems. Our findings highlight strengths and weaknesses of available bioinformatic tools for investigating the taxonomic diversity of viruses in benthic ecosystems in order to improve our comprehension of viral diversity in the oceans and its relationships with host diversity and ecosystem functioning. PMID:27329207

  14. Assessing viral taxonomic composition in benthic marine ecosystems: reliability and efficiency of different bioinformatic tools for viral metagenomic analyses.

    PubMed

    Tangherlini, M; Dell'Anno, A; Zeigler Allen, L; Riccioni, G; Corinaldesi, C

    2016-01-01

    In benthic deep-sea ecosystems, which represent the largest biome on Earth, viruses have a recognised key ecological role, but their diversity is still largely unknown. Identifying the taxonomic composition of viruses is crucial for understanding virus-host interactions, their role in food web functioning and evolutionary processes. Here, we compared the performance of various bioinformatic tools (BLAST, MG-RAST, NBC, VMGAP, MetaVir, VIROME) for analysing the viral taxonomic composition in simulated viromes and viral metagenomes from different benthic deep-sea ecosystems. The analyses of simulated viromes indicate that all the BLAST tools, followed by MetaVir and VMGAP, are more reliable in the affiliation of viral sequences and strains. When analysing the environmental viromes, tBLASTx, MetaVir, VMGAP and VIROME showed a similar efficiency of sequence annotation; however, MetaVir and tBLASTx identified a higher number of viral strains. These latter tools also identified a wider range of viral families than the others, providing a wider view of viral taxonomic diversity in benthic deep-sea ecosystems. Our findings highlight strengths and weaknesses of available bioinformatic tools for investigating the taxonomic diversity of viruses in benthic ecosystems in order to improve our comprehension of viral diversity in the oceans and its relationships with host diversity and ecosystem functioning. PMID:27329207

  15. Failure of Viral Shells

    NASA Astrophysics Data System (ADS)

    Klug, William S.; Bruinsma, Robijn F.; Michel, Jean-Philippe; Knobler, Charles M.; Ivanovska, Irena L.; Schmidt, Christoph F.; Wuite, Gijs J. L.

    2006-12-01

    We report a combined theoretical and experimental study of the structural failure of viral shells under mechanical stress. We find that discontinuities in the force-indentation curve associated with failure should appear when the so-called Föppl von Kármán (FvK) number exceeds a critical value. A nanoindentation study of a viral shell subject to a soft-mode instability, where the stiffness of the shell decreases with increasing pH, confirms the predicted onset of failure as a function of the FvK number.

  16. Incidence of Etiologic Factors in Squamous Cell Carcinoma of Head and Neck in Ahvaz

    PubMed Central

    Nikakhlagh, Soheila; Saki, Nader; shoar, Mahmood Hekmat; Sartipipor, Amin; Saki, Sara

    2012-01-01

    Introduction: Squamous cell carcinoma (SCC) is the most common head and neck malignancy. Smoking, alcohol consumption, viral infections, exposure, oral hygiene, and dietary, genetic, and occupational factors are the most important etiologic factors. The aim of this study was determining the incidence of etiologic factors in head and neck SCC. Materials and Methods: This is a cross-sectional survey study for the determination of the etiologic factors of head and neck squamous cell carcinoma over a five-year period in the Otolaryngology Department of the Imam Khomeini & Golestan hospitals in Ahwaz. Results: 176 patients, comprising 151(85.8%) men and 25(14.2%) women, were studied. Overall mean age was 67.2 years. 148 (84.1%) patients were smokers. prolong exposure to chemical fertilizer in 101 (57.4%) patients, Sun exposure in 21 (11.9%) patients, Low socioeconomic status in 124 (70.5%) patients, poor oral hygiene in 128 (72.7%) patients, high intake of hot tea drinking in 84 (47.7%) patients and malignancies in family in 12 (6.8%) patients were the most frequent risk factors. 17 (9.6%) patients have had opioid addiction and HPV was positive in 7 (3.9%) patients by PCR. Conclusion: According to this study, tobacco smoking was the most important etiologic factor and had a strong effect on risk of head and neck squamous cell carcinoma. Other factors are also important and need more research study. PMID:24303391

  17. Future Directions in ADHD Etiology Research

    ERIC Educational Resources Information Center

    Nigg, Joel T.

    2012-01-01

    Reviews salient emerging themes in the scientific literature related to identifying etiology and pathophysiology of ADHD. While bypassing the need for new treatment research, the review highlights three themes. First, recognition of the epigenetic effects is expected to revitalize the search for and mapping of early environmental influences on the…

  18. Recent Research on the Etiologies of Autism.

    ERIC Educational Resources Information Center

    Fisher, Eileen; Van Dyke, Don C.; Sears, Lonnie; Matzen, Jane; Lin-Dyken, Deborah; McBrien, Dianne M.

    1999-01-01

    Reviews recent research on the etiologies of autism, including genetic research, anatomic and neuroimaging studies, topics in neurophysiology research (including serotonin, dopamine, and opiods), immunologic research, studies of autism phenotype, and electroencephalographic studies. It concludes that, as of yet, research has found no clear…

  19. Identification of Genetic Regions Associated with Bovine Viral Diarrhea-Persistently Infected Cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine viral diarrhea virus (BVDV) is one of the etiologies involved in bovine respiratory disease (BRD). BVDV infection can also cause reproductive disorders and acute fatal hemorrhagic disease resulting in poor performance and economic losses to the cattle industry. Infection with BVDV can be tra...

  20. Viral diseases of the rabbit.

    PubMed

    Krogstad, Aric P; Simpson, Janet E; Korte, Scott W

    2005-01-01

    Viral disease in the rabbit is encountered infrequently by the clinical practitioner; however, several viral diseases were reported to occur in this species. Viral diseases that are described in the rabbit primarily may affect the integument, gastrointestinal tract or, central nervous system or maybe multi-systemic in nature. Rabbit viral diseases range from oral papillomatosis, with benign clinical signs, to rabbit hemorrhagic disease and myxomatosis, which may result in significant clinical disease and mortality. The wild rabbit may serve as a reservoir for disease transmission for many of these viral agents. In general, treatment of viral disease in the rabbit is supportive in nature. PMID:15585192

  1. Etiologic Agents of Central Nervous System Infections among Febrile Hospitalized Patients in the Country of Georgia

    PubMed Central

    Akhvlediani, Tamar; Bautista, Christian T.; Shakarishvili, Roman; Tsertsvadze, Tengiz; Imnadze, Paata; Tatishvili, Nana; Davitashvili, Tamar; Samkharadze, Tamar; Chlikadze, Rusudan; Dvali, Natia; Dzigua, Lela; Karchava, Mariam; Gatserelia, Lana; Macharashvili, Nino; Kvirkvelia, Nana; Habashy, Engy Emil; Farrell, Margaret; Rowlinson, Emily; Sejvar, James; Hepburn, Matthew; Pimentel, Guillermo; Dueger, Erica; House, Brent; Rivard, Robert

    2014-01-01

    Objectives There is a large spectrum of viral, bacterial, fungal, and prion pathogens that cause central nervous system (CNS) infections. As such, identification of the etiological agent requires multiple laboratory tests and accurate diagnosis requires clinical and epidemiological information. This hospital-based study aimed to determine the main causes of acute meningitis and encephalitis and enhance laboratory capacity for CNS infection diagnosis. Methods Children and adults patients clinically diagnosed with meningitis or encephalitis were enrolled at four reference health centers. Cerebrospinal fluid (CSF) was collected for bacterial culture, and in-house and multiplex RT-PCR testing was conducted for herpes simplex virus (HSV) types 1 and 2, mumps virus, enterovirus, varicella zoster virus (VZV), Streptococcus pneumoniae, HiB and Neisseria meningitidis. Results Out of 140 enrolled patients, the mean age was 23.9 years, and 58% were children. Bacterial or viral etiologies were determined in 51% of patients. Five Streptococcus pneumoniae cultures were isolated from CSF. Based on in-house PCR analysis, 25 patients were positive for S. pneumoniae, 6 for N. meningitidis, and 1 for H. influenzae. Viral multiplex PCR identified infections with enterovirus (n = 26), VZV (n = 4), and HSV-1 (n = 2). No patient was positive for mumps or HSV-2. Conclusions Study findings indicate that S. pneumoniae and enteroviruses are the main etiologies in this patient cohort. The utility of molecular diagnostics for pathogen identification combined with the knowledge provided by the investigation may improve health outcomes of CNS infection cases in Georgia. PMID:25369023

  2. Viral respiratory diseases in children: classification, etiology, epidemiology, and risk factors.

    PubMed

    Hemming, V G

    1994-05-01

    The epidemiology, molecular structure, cell tropism, and pathophysiology of many human disease-causing viruses have been painstakingly and elegantly characterized during the past 50 years. Vaccines and antiviral drugs of varying efficacy were developed and tested. Despite the relegation of smallpox to a freezer chest and the progress in the control of measles and hepatitis B, the viruses that cause respiratory tract infections remain significant causes of illness and death in pediatric populations worldwide. This discussion surveys the virus groups that contain nearly 200 distinct viruses that cause sporadic and epidemic respiratory infections in children. The epidemiology of infection with the influenza A and B, parainfluenza, and respiratory syncytial viruses and adenoviruses and their impact on infants and children and the groups at highest risk for morbid outcomes are discussed. PMID:8169752

  3. Inflammatory response in mixed viral-bacterial community-acquired pneumonia

    PubMed Central

    2014-01-01

    Background The role of mixed pneumonia (virus + bacteria) in community-acquired pneumonia (CAP) has been described in recent years. However, it is not known whether the systemic inflammatory profile is different compared to monomicrobial CAP. We wanted to investigate this profile of mixed viral-bacterial infection and to compare it to monomicrobial bacterial or viral CAP. Methods We measured baseline serum procalcitonin (PCT), C reactive protein (CRP), and white blood cell (WBC) count in 171 patients with CAP with definite etiology admitted to a tertiary hospital: 59 (34.5%) bacterial, 66 (39.%) viral and 46 (27%) mixed (viral-bacterial). Results Serum PCT levels were higher in mixed and bacterial CAP compared to viral CAP. CRP levels were higher in mixed CAP compared to the other groups. CRP was independently associated with mixed CAP. CRP levels below 26 mg/dL were indicative of an etiology other than mixed in 83% of cases, but the positive predictive value was 45%. PCT levels over 2.10 ng/mL had a positive predictive value for bacterial-involved CAP versus viral CAP of 78%, but the negative predictive value was 48%. Conclusions Mixed CAP has a different inflammatory pattern compared to bacterial or viral CAP. High CRP levels may be useful for clinicians to suspect mixed CAP. PMID:25073709

  4. BOVINE VIRAL DIARRHEA VIRUSES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine viral diarrhea virus (BVDV) is an umbrella term for two species of viruses, BVDV1 and BVDV2, within the Pestivirus genus of the Flavivirus family. BVDV viruses are further subclassified as cytopathic and noncytopathic based on their activity in cultured epithelial cells. Noncytopathic BVDV p...

  5. BIOMARKERS OF VIRAL EXPOSURE

    EPA Science Inventory

    Viral and protozoan pathogens associated with raw sludge can cause encephalitis, gastroenteritis, hepatitis, myocarditis, and a number of other diseases. Raw sludge that has been treated to reduce these pathogens can be used for land application according to the regulations spec...

  6. Transport of viral specimens.

    PubMed Central

    Johnson, F B

    1990-01-01

    The diagnosis of viral infections by culture relies on the collection of proper specimens, proper care to protect the virus in the specimens from environmental damage, and use of an adequate transport system to maintain virus activity. Collection of specimens with swabs that are toxic to either virus or cell culture should be avoided. A variety of transport media have been formulated, beginning with early bacteriological transport media. Certain swab-tube combinations have proven to be both effective and convenient. Of the liquid transport media, sucrose-based and broth-based media appear to be the most widely accepted and used. Studies on virus stability show that most viruses tested are sufficiently stable in transport media to withstand a transport time of 1 to 3 days. Some viruses may withstand longer transport times. In many cases, it is not necessary to store virus specimens in a refrigerator or send them to the laboratory on wet ice or frozen on dry ice. However, the specimen should not be exposed to environmental extremes. Modern viral transport media allow for more effective use of viral culture and culture enhancement techniques for the diagnosis of human viral infections. PMID:2187591

  7. WATERBORNE VIRAL GASTROENTERITIS

    EPA Science Inventory

    In the study of human gastroenteritis, the use of electron microscopy and related techniques has led to the identification of new viral agents which had previously escaped detection by routine cell-culture procedures. Efforts to characterize and further study these agents are cur...

  8. Leafhopper viral pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four newly discovered viral pathogens in leafhopper vectors of Pierce’s disease of grapes, have been shown to replicate in sharpshooter leafhoppers; the glassy-winged sharpshooter, GWSS, Homalodisca vitripennis, and Oncometopia nigricans (Hemiptera: Cicadellidae). The viruses were classified as memb...

  9. Bovine viral diarrhea viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infections with bovine viral diarrhea viruses (BVDV) result in significant economic losses for beef and dairy producers worldwide. BVDV is actually an umbrella term for two species of viruses, BVDV1 and BVDV2, within the Pestivirus genus of the Flavivirus family. While denoted as a bovine pathogen...

  10. Gene Expression Signatures Diagnose Influenza and Other Symptomatic Respiratory Viral Infection in Humans

    PubMed Central

    Zaas, Aimee K.; Chen, Minhua; Varkey, Jay; Veldman, Timothy; Hero, Alfred O.; Lucas, Joseph; Huang, Yongsheng; Turner, Ronald; Gilbert, Anthony; Lambkin-Williams, Robert; Øien, N. Christine; Nicholson, Bradly; Kingsmore, Stephen; Carin, Lawrence; Woods, Christopher W.; Ginsburg, Geoffrey S.

    2010-01-01

    Summary Acute respiratory infections (ARI) are a common reason for seeking medical attention and the threat of pandemic influenza will likely add to these numbers. Using human viral challenge studies with live rhinovirus, respiratory syncytial virus, and influenza A, we developed peripheral blood gene expression signatures that distinguish individuals with symptomatic ARI from uninfected individuals with > 95% accuracy. We validated this “acute respiratory viral” signature - encompassing genes with a known role in host defense against viral infections - across each viral challenge. We also validated the signature in an independently acquired dataset for influenza A and classified infected individuals from healthy controls with 100% accuracy. In the same dataset, we could also distinguish viral from bacterial ARIs (93% accuracy). These results demonstrate that ARIs induce changes in human peripheral blood gene expression that can be used to diagnose a viral etiology of respiratory infection and triage symptomatic individuals. PMID:19664979

  11. Challenges in the Etiology and Diagnosis of Acute Febrile Illness in Children in Low- and Middle-Income Countries.

    PubMed

    Iroh Tam, Pui-Ying; Obaro, Stephen K; Storch, Gregory

    2016-06-01

    Acute febrile illness is a common cause of hospital admission, and its associated infectious causes contribute to substantial morbidity and death among children worldwide, especially in low- and middle-income countries. Declining transmission of malaria in many regions, combined with the increasing use of rapid diagnostic tests for malaria, has led to the increasing recognition of leptospirosis, rickettsioses, respiratory viruses, and arboviruses as etiologic agents of fevers. However, clinical discrimination between these etiologies can be difficult. Overtreatment with antimalarial drugs is common, even in the setting of a negative test result, as is overtreatment with empiric antibacterial drugs. Viral etiologies remain underrecognized and poorly investigated. More-sensitive diagnostics have led to additional dilemmas in discriminating whether a positive test result reflects a causative pathogen. Here, we review and summarize the current epidemiology and focus particularly on children and the challenges for future research. PMID:27059657

  12. Outbreaks of food-borne and waterborne viral gastroenteritis.

    PubMed Central

    Hedberg, C W; Osterholm, M T

    1993-01-01

    Norwalk virus infection is the epidemiologic prototype for outbreaks of food-borne and waterborne gastroenteritis. Around the world, Norwalk virus and Norwalk-like viruses appear to be major causes of food-borne and waterborne illness. Assessment of the overall significance of viral agents to the epidemiology of food-borne and waterborne illness is hampered by the lack of surveillance throughout much of the world. In areas where food-borne and waterborne illness surveillance is conducted, outbreaks of viral gastroenteritis are underreported because of the lack of availability of routine laboratory services to confirm the viral etiology. Routine use of epidemiologic criteria as an alternative to laboratory confirmation will allow better assessments of the importance of viral gastroenteritis until effective laboratory methods can be widely implemented. Outbreaks of viral gastroenteritis have been propagated by contamination of water supplies, raw foods, and ill food handlers. Controlling an outbreak depends on identifying and removing the source of contamination. The demonstrated occurrence of person-to-person transmission and the likely occurrence of transmission of Norwalk-like viruses by aerosol make it necessary to evaluate the potential for transmission by food handlers and servers in every outbreak, regardless of primary source. PMID:8395330

  13. Non-viral factors contributing to hepatocellular carcinoma

    PubMed Central

    Hamed, Manal A; Ali, Sanaa A

    2013-01-01

    Hepatocellular carcinoma (HCC) is a major cause of cancer death worldwide, accounting for over half a million deaths per year. The geographic pattern of HCC incidence is parallel to exposure to viral etiologic factors. Its incidence is increasing, ranging between 3% and 9% annually depending on the geographical location, and variability in the incidence rates correspond closely to the prevalence and pattern of the primary etiologic factors. Chronic infections with hepatitis B viruses or hepatitis C viruses have both been recognized as human liver carcinogens with a combined attributable fraction of at least 75% of all HCC cases. Multiple non-viral factors have been implicated in the development of HCC. Increased body mass index and diabetes with subsequent development of non-alcoholic steatohepatitis represent significant risk factors for HCC. Other non-viral causes of HCC include iron overload syndromes, alcohol use, tobacco, oral contraceptive, aflatoxin, pesticides exposure and betel quid chewing, a prevalent habit in the developing world. Wilson disease, α-1 antitrypsin deficiency, Porphyrias, autoimmune hepatitis, Schistosoma japonicum associated with positive hepatitis B surface antigen, and thorotrast-ray are also contributing hepatocellualar carcinoma. In addition, primary biliary cirrhosis, congestive liver disease and family history of liver cancer increase the risk of HCC incident. In conclusion, clarification of relevant non-viral causes of HCC will help to focus clinicians on those risk factors that are modifiable. The multilevel preventative approach will hopefully lead to a reduction in incidence of non-viral HCC, and a decrease in the patient morbidity and mortality as well as the societal economic burden associated with HCC. PMID:23805355

  14. Future Directions in ADHD Etiology Research

    PubMed Central

    Nigg, Joel T.

    2015-01-01

    Reviews salient emerging themes in the scientific literature related to identifying etiology and pathophysiology of ADHD. While bypassing the need for new treatment research, the review highlights three themes. First, recognition of the epigenetic effects is expected to revitalize the search for and mapping of early environmental influences on the development of ADHD. Second, neurobiological findings will have limited impact if not examined in the context of significant race and cultural variation in ADHD-related developmental processes, and in the context of rapidly changing social and technological contexts of children’s development worldwide. Third, further examination of the phenotype and characterization of its dimensional and categorical structure remains a major need. Overall, the coming decades of etiology research on ADHD will be expected to capitalize on new scientific tools. The hope in the field is that new insights into fundamental prevention can emerge. PMID:22642834

  15. [Genetic factors in etiology of uterine fibroids].

    PubMed

    Kubínová, K; Mára, M; Horák, P; Kuzel, D

    2012-02-01

    Uterine fibroids are the most common pelvic tumors in women of reproductive age. The cause of development of uterine fibroids is still unknown, however recent cytogenetic and genetic studies led to advancement in understanding of etiology of these tumors. In accordance with the latest findings up to 40% of uterine fibroids bear some chromosomal abnormalities. The most common are aberration of chromosomes 6, 7, 12 and 14. Uterine fibroids have been linked to mutations of fumarate hydratase (FH) gene. Germline mutations in FH gene cause autosomal dominant syndromes MCUL1 (multiple cutaneous and uterine leiomyomata) and HLRCC (hereditary leiomyomatosis and renal cell cancer), characterized by multiple uterine and cutaneous leiomyomata and renal cancer. This paper reviews recent findings in the role of genetic in etiology of uterine fibroids. PMID:22536642

  16. Facial Dysostoses: Etiology, Pathogenesis and Management

    PubMed Central

    Trainor, Paul A.; Andrews, Brian T.

    2013-01-01

    Approximately 1% of all live births exhibit a minor or major congenital anomaly. Of these approximately one-third display craniofacial abnormalities which are a significant cause of infant mortality and dramatically affect national health care budgets. To date, more than 700 distinct craniofacial syndromes have been described and in this review, we discuss the etiology, pathogenesis and management of facial dysostoses with a particular emphasis on Treacher Collins, Nager and Miller syndromes. As we continue to develop and improve medical and surgical care for the management of individual conditions, it is essential at the same time to better characterize their etiology and pathogenesis. Here we describe recent advances in our understanding of the development of facial dysostosis with a view towards early in-utero identification and intervention which could minimize the manifestation of anomalies prior to birth. The ultimate management for any craniofacial anomaly however, would be prevention and we discuss this possibility in relation to facial dysostosis. PMID:24123981

  17. Etiology of maxillary canine impaction: a review.

    PubMed

    Becker, Adrian; Chaushu, Stella

    2015-10-01

    This article is a review that enumerates the causes of impaction of the maxillary permanent canines, including hard tissue obstructions, soft tissue lesions, and anomalies of neighboring teeth, and discusses the much-argued relationship between environmental and genetic factors. These phenomena have been shown in many investigations to accompany the diagnosis of canine impaction and have been presented as unrelated anomalous features, each of which is etiologically construed as genetic, including the aberrant canine itself. While in general the influence of genetics pervades the wider picture, a guidance theory proposes an alternative etiologic line of reasoning and interpretation of these studies, in which the same genetically determined anomalous features provide an abnormal milieu in which the canine is reared and from which it is guided in its misdirected and often abortive path of eruption. PMID:26432311

  18. Viral Communities Associated with Human Pericardial Fluids in Idiopathic Pericarditis

    PubMed Central

    Fancello, Laura; Monteil, Sonia; Popgeorgiev, Nikolay; Rivet, Romain; Gouriet, Frédérique; Fournier, Pierre-Edouard; Raoult, Didier; Desnues, Christelle

    2014-01-01

    Pericarditis is a common human disease defined by inflammation of the pericardium. Currently, 40% to 85% of pericarditis cases have no identified etiology. Most of these cases are thought to be caused by an infection of undetected, unsuspected or unknown viruses. In this work, we used a culture- and sequence-independent approach to investigate the viral DNA communities present in human pericardial fluids. Seven viral metagenomes were generated from the pericardial fluid of patients affected by pericarditis of unknown etiology and one metagenome was generated from the pericardial fluid of a sudden infant death case. As a positive control we generated one metagenome from the pericardial fluid of a patient affected by pericarditis caused by herpesvirus type 3. Furthermore, we used as negative controls a total of 6 pericardial fluids from 6 different individuals affected by pericarditis of non-infectious origin: 5 of them were sequenced as a unique pool and the remaining one was sequenced separately. The results showed a significant presence of torque teno viruses especially in one patient, while herpesviruses and papillomaviruses were present in the positive control. Co-infections by different genotypes of the same viral type (torque teno viruses) or different viruses (herpesviruses and papillomaviruses) were observed. Sequences related to bacteriophages infecting Staphylococcus, Enterobacteria, Streptococcus, Burkholderia and Pseudomonas were also detected in three patients. This study detected torque teno viruses and papillomaviruses, for the first time, in human pericardial fluids. PMID:24690743

  19. Neurodegenerative Diseases: Neurotoxins as Sufficient Etiologic Agents?

    PubMed Central

    Shaw, Christopher A.; Höglinger, Günter U.

    2008-01-01

    A dominant paradigm in neurological disease research is that the primary etiological factors for diseases such as Alzheimer’s (AD), Parkinson’s (PD), and amyotrophic lateral sclerosis (ALS) are genetic. Opposed to this perspective are the clear observations from epidemiology that purely genetic casual factors account for a relatively small fraction of all cases. Many who support a genetic etiology for neurological disease take the view that while the percentages may be relatively small, these numbers will rise in the future with the inevitable discoveries of additional genetic mutations. The follow up argument is that even if the last is not true, the events triggered by the aberrant genes identified so far will be shown to impact the same neuronal cell death pathways as those activated by environmental factors that trigger most sporadic disease cases. In this article we present a countervailing view that environmental neurotoxins may be the sole sufficient factor in at least three neurological disease clusters. For each, neurotoxins have been isolated and characterized that, at least in animal models, faithfully reproduce each disorder without the need for genetic co-factors. Based on these data, we will propose a set of principles that would enable any potential toxin to be evaluated as an etiological factor in a given neurodegenerative disease. Finally, we will attempt to put environmental toxins into the context of possible genetically-determined susceptibility. PMID:17985252

  20. Interstitial cystitis. Etiology, diagnosis, and treatment.

    PubMed Central

    Nickel, J. C.

    2000-01-01

    OBJECTIVE: To review current knowledge about the epidemiology, etiology, diagnosis, and treatment of interstitial cystitis, with special emphasis on management of this condition by family physicians. QUALITY OF EVIDENCE: Articles were identified through MEDLINE and review of abstracts presented at Urology and Interstitial Cystitis meetings during the last decade. Recent reviews were further searched for additional studies and trials. Data were summarized from large epidemiologic studies. Etiologic theories were extracted from current concepts and reviews of scientific studies. Diagnostic criteria described in this review are based on clinical interpretation of National Institutes of Health (NIH) research guidelines, interpretation of data from the NIH Interstitial Cystitis Cohort Study, and recent evidence on use of the potassium sensitivity test. Treatment suggestions are based on six randomized placebo-controlled clinical treatment trials and best available clinical data. MAIN MESSAGE: Interstitial cystitis affects about 0.01% to 0.5% of women. Its etiology is unknown, but might involve microbiologic, immunologic, mucosal, neurogenic, and other yet undefined agents. The diagnosis of interstitial cystitis is a diagnosis of exclusion. It is impossible to provide a purely evidence-based treatment strategy, but review of available evidence suggests that conservative supportive therapy (including diet modification); oral treatment with pentosan polysulfate, amitriptyline, or hydroxyzine; and intravesical treatments with heparinlike medications, dimethyl sulfoxide, or BCG vaccine could benefit some patients. CONCLUSION: Family physicians should have an understanding of interstitial cystitis and be able to make a diagnosis and formulate an evidence-based treatment strategy for their patients. PMID:11153410

  1. Viral Membrane Scission

    PubMed Central

    Rossman, Jeremy S.; Lamb, Robert A.

    2014-01-01

    Virus budding is a complex, multistep process in which viral proteins make specific alterations in membrane curvature. Many different viral proteins can deform the membrane and form a budding virion, but very few can mediate membrane scission to complete the budding process. As a result, enveloped viruses have developed numerous ways of facilitating membrane scission, including hijacking host cellular scission machinery and expressing their own scission proteins. These proteins mediate scission in very different ways, though the biophysical mechanics underlying their actions may be similar. In this review, we explore the mechanisms of membrane scission and the ways in which enveloped viruses use these systems to mediate the release of budding virions. PMID:24099087

  2. Viral membrane fusion

    PubMed Central

    Harrison, Stephen C.

    2015-01-01

    Membrane fusion is an essential step when enveloped viruses enter cells. Lipid bilayer fusion requires catalysis to overcome a high kinetic barrier; viral fusion proteins are the agents that fulfill this catalytic function. Despite a variety of molecular architectures, these proteins facilitate fusion by essentially the same generic mechanism. Stimulated by a signal associated with arrival at the cell to be infected (e.g., receptor or co-receptor binding, proton binding in an endosome), they undergo a series of conformational changes. A hydrophobic segment (a “fusion loop” or “fusion peptide”) engages the target-cell membrane and collapse of the bridging intermediate thus formed draws the two membranes (virus and cell) together. We know of three structural classes for viral fusion proteins. Structures for both pre- and postfusion conformations of illustrate the beginning and end points of a process that can be probed by single-virion measurements of fusion kinetics. PMID:25866377

  3. Viral membrane fusion

    SciTech Connect

    Harrison, Stephen C.

    2015-05-15

    Membrane fusion is an essential step when enveloped viruses enter cells. Lipid bilayer fusion requires catalysis to overcome a high kinetic barrier; viral fusion proteins are the agents that fulfill this catalytic function. Despite a variety of molecular architectures, these proteins facilitate fusion by essentially the same generic mechanism. Stimulated by a signal associated with arrival at the cell to be infected (e.g., receptor or co-receptor binding, proton binding in an endosome), they undergo a series of conformational changes. A hydrophobic segment (a “fusion loop” or “fusion peptide”) engages the target-cell membrane and collapse of the bridging intermediate thus formed draws the two membranes (virus and cell) together. We know of three structural classes for viral fusion proteins. Structures for both pre- and postfusion conformations of illustrate the beginning and end points of a process that can be probed by single-virion measurements of fusion kinetics. - Highlights: • Viral fusion proteins overcome the high energy barrier to lipid bilayer merger. • Different molecular structures but the same catalytic mechanism. • Review describes properties of three known fusion-protein structural classes. • Single-virion fusion experiments elucidate mechanism.

  4. Optimizing Viral Discovery in Bats

    PubMed Central

    Young, Cristin C. W.; Olival, Kevin J.

    2016-01-01

    Viral discovery studies in bats have increased dramatically over the past decade, yet a rigorous synthesis of the published data is lacking. We extract and analyze data from 93 studies published between 2007–2013 to examine factors that increase success of viral discovery in bats, and specific trends and patterns of infection across host taxa and viral families. Over the study period, 248 novel viruses from 24 viral families have been described. Using generalized linear models, at a study level we show the number of host species and viral families tested best explained number of viruses detected. We demonstrate that prevalence varies significantly across viral family, specimen type, and host taxonomy, and calculate mean PCR prevalence by viral family and specimen type across all studies. Using a logistic model, we additionally identify factors most likely to increase viral detection at an individual level for the entire dataset and by viral families with sufficient sample sizes. Our analysis highlights major taxonomic gaps in recent bat viral discovery efforts and identifies ways to improve future viral pathogen detection through the design of more efficient and targeted sample collection and screening approaches. PMID:26867024

  5. Optimizing Viral Discovery in Bats.

    PubMed

    Young, Cristin C W; Olival, Kevin J

    2016-01-01

    Viral discovery studies in bats have increased dramatically over the past decade, yet a rigorous synthesis of the published data is lacking. We extract and analyze data from 93 studies published between 2007-2013 to examine factors that increase success of viral discovery in bats, and specific trends and patterns of infection across host taxa and viral families. Over the study period, 248 novel viruses from 24 viral families have been described. Using generalized linear models, at a study level we show the number of host species and viral families tested best explained number of viruses detected. We demonstrate that prevalence varies significantly across viral family, specimen type, and host taxonomy, and calculate mean PCR prevalence by viral family and specimen type across all studies. Using a logistic model, we additionally identify factors most likely to increase viral detection at an individual level for the entire dataset and by viral families with sufficient sample sizes. Our analysis highlights major taxonomic gaps in recent bat viral discovery efforts and identifies ways to improve future viral pathogen detection through the design of more efficient and targeted sample collection and screening approaches. PMID:26867024

  6. Bovine viral diarrhea virus: global status.

    PubMed

    Ridpath, Julia F

    2010-03-01

    Despite the success of regional bovine viral diarrhea viruses (BVDV) eradication programs, infections remain a source of economic loss for producers. The wide variation among BVDV results in differences in genotype, biotype, virulence, and types of infections. BVDV infect a range of domestic and wild ruminants. Clinical presentation varies depending on strain of virus, species of host, immune status of host, reproductive status of host, age of host, and concurrent infections. Recent advances in BVDV research and diagnostics have led to the development of regional eradication/control programs, the most efficacious of which focus on biosecurity, surveillance, and control. PMID:20117546

  7. Viral population estimation using pyrosequencing.

    PubMed

    Eriksson, Nicholas; Pachter, Lior; Mitsuya, Yumi; Rhee, Soo-Yon; Wang, Chunlin; Gharizadeh, Baback; Ronaghi, Mostafa; Shafer, Robert W; Beerenwinkel, Niko

    2008-04-01

    The diversity of virus populations within single infected hosts presents a major difficulty for the natural immune response as well as for vaccine design and antiviral drug therapy. Recently developed pyrophosphate-based sequencing technologies (pyrosequencing) can be used for quantifying this diversity by ultra-deep sequencing of virus samples. We present computational methods for the analysis of such sequence data and apply these techniques to pyrosequencing data obtained from HIV populations within patients harboring drug-resistant virus strains. Our main result is the estimation of the population structure of the sample from the pyrosequencing reads. This inference is based on a statistical approach to error correction, followed by a combinatorial algorithm for constructing a minimal set of haplotypes that explain the data. Using this set of explaining haplotypes, we apply a statistical model to infer the frequencies of the haplotypes in the population via an expectation-maximization (EM) algorithm. We demonstrate that pyrosequencing reads allow for effective population reconstruction by extensive simulations and by comparison to 165 sequences obtained directly from clonal sequencing of four independent, diverse HIV populations. Thus, pyrosequencing can be used for cost-effective estimation of the structure of virus populations, promising new insights into viral evolutionary dynamics and disease control strategies. PMID:18437230

  8. Complete genome sequence of Yersinia ruckeri str. CSF007-82, etiologic agent of enteric redmouth disease in salmonid fish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We present the complete, closed and finished chromosomal and extra-chromosomal genome sequences of Y. ruckeri strain CSF007-82, etiologic agent of enteric red mouth disease in salmonid fish. The chromosome is 3,799,036 bp with a G+C content of 47.5% and encodes 3,530 predicted CDS, 7 ribosomal opero...

  9. The etiology of pelvic inflammatory disease.

    PubMed

    Keith, L; Berger, G S

    1984-05-01

    The etiology of pelvic inflammatory disease (PID) is speculated upon based on reported incidence and epidemiological studies. In Western society, the incidence of PID (annual) is 1% among women aged 15-34 years and 2% in the high risk group of women aged 15-24 years. The annual incidence in the US is higher, at least 2% among fecund sexually active women aged 13-44 years. The medical consequences of PID are infertility, ectopic pregnancy, and chronic pelvic pain. Causative agents include Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma hominis and various other aerobic and anaerobic microorganisms; however, the natural genital flora of females is so varied that determining actual causative agents is difficult. some case-control studies have determined risk factors for PID; these include particularly current or prior use of IUD, prior pelvic surgery, sexual activity (including number of partners), race, and prior PID acute infection. PID is not a sexually transmitted disease, but rather is classified as sexually derived. Use of barrier methods and oral contraceptives protects against PID. IUD use greatly increases the risk of PID, probably because of the avenue the device provides for organisms to ascend from the lower to the upper genital tract. The role of males in PID etiology is currently the subject of much discussion. It is theorized that the mechanical action of penis insertion in intercourse helps to move causative agents to the upper genital region; also, semen may carry vaginal flora through the cervical opening into the uterus and tubes. Menstruation and PID are closely associated, perhaps because the cervix dilates during bleedings. Research areas include: determination of role of sexual activity (and number of partners) in PID etiology; evaluation of events of menstruation that are predisposing; evaluation of relationship between bacteriosperma and lower and upper genital infections; relationship of particular contraceptive methods to PID

  10. Etiology, classification, and treatment of urticaria.

    PubMed

    Guldbakke, Kjetil Kristoffer; Khachemoune, Amor

    2007-01-01

    Urticaria is among the most common skin diseases. It can be acute, chronic, mediated by a physical stimulus, or related to contact with an urticant. Some cases result from an underlying small vessel vasculitis. Our understanding of this condition is continuously expanding, and autoimmune mechanisms are now recognized as a cause of chronic urticaria. A search of the PubMed database (US National Library of Medicine) for "urticaria" yields more than 12,000 results. Our goal is to discuss the current understanding of the etiology, classification, and treatment alternatives. As the topic is comprehensive, our discussion will be limited to a concise review. PMID:17330621

  11. Recovering full-length viral genomes from metagenomes

    PubMed Central

    Smits, Saskia L.; Bodewes, Rogier; Ruiz-González, Aritz; Baumgärtner, Wolfgang; Koopmans, Marion P.; Osterhaus, Albert D. M. E.; Schürch, Anita C.

    2015-01-01

    Infectious disease metagenomics is driven by the question: “what is causing the disease?” in contrast to classical metagenome studies which are guided by “what is out there?” In case of a novel virus, a first step to eventually establishing etiology can be to recover a full-length viral genome from a metagenomic sample. However, retrieval of a full-length genome of a divergent virus is technically challenging and can be time-consuming and costly. Here we discuss different assembly and fragment linkage strategies such as iterative assembly, motif searches, k-mer frequency profiling, coverage profile binning, and other strategies used to recover genomes of potential viral pathogens in a timely and cost-effective manner. PMID:26483782

  12. [Etiopathogenetic approach to the treatment of viral-bacterial pneumonias].

    PubMed

    Nekliudova, L I; Fedorova, Iu B; Pasternak, N A; Shenderovich, V A; Petrushanskaia, G A

    1976-12-01

    The efficacy of aerosols of leukocytal interferon used in complex with antibacterial and other medicamentous agents was studied during influenza epidemic in 1975 due to Port-Chalmers virus of influenza A with increased numbers of viral-bacterial pneumonia. The viral-sta-phylococcal etiology of the infection was confirmed in 80 per cent of the cases under stationary conditions. Various microorganism and most often Staph aureus were isolated in addition to the viruses from the patient's sputum and washings and their antibioticograms were determined. The studies showed that the complex treatment of the patients with virologically and serologically confirmed diagnosis of the disease resulted in decreased duration of the disease, less pronounced intoxication and more rapid resorption of the changes in the lung tissue. PMID:828482

  13. Etiologies and Management of Aseptic Meningitis in Patients Admitted to an Internal Medicine Department

    PubMed Central

    Jarrin, Irène; Sellier, Pierre; Lopes, Amanda; Morgand, Marjolaine; Makovec, Tamara; Delcey, Veronique; Champion, Karine; Simoneau, Guy; Green, Andrew; Mouly, Stéphane; Bergmann, Jean-François; Lloret-Linares, Célia

    2016-01-01

    Abstract Several studies have focused on the clinical and biological characteristics of meningitis in order to distinguish between bacterial and viral meningitis in the emergency setting. However, little is known about the etiologies and outcomes of aseptic meningitis in patients admitted to Internal Medicine. The aim of the study is to describe the etiologies, characteristics, and outcomes of aseptic meningitis with or without encephalitis in adults admitted to an Internal Medicine Department. A retrospective cohort study was conducted in the Internal Medicine Department of the Lariboisière Hospital in Paris, France, from January 2009 to December 2011. Clinical and biological characteristics of aseptic meningitis were recorded. These included cerebrospinal fluid analysis, results of polymerase chain reaction testing, final diagnoses, and therapeutic management. The cohort included 180 patients fulfilling the criteria for aseptic meningitis with (n = 56) or without (n = 124) encephalitis. A definitive etiological diagnosis was established in 83 of the 180 cases. Of the cases with a definitive diagnosis, 73 were due to infectious agents, mainly enteroviruses, Herpes Simplex Virus 2, and Varicella Zoster Virus (43.4%, 16.8%, and 14.5% respectively). Inflammatory diseases were diagnosed in 7 cases. Among the 97 cases without definitive diagnoses, 26 (26.8%) remained free of treatment throughout their management whereas antiviral or antibiotic therapy was initiated in the emergency department for the remaining 71 patients. The treatment was discontinued in only 10 patients deemed to have viral meningitis upon admission to Internal Medicine. The prevalence of inflammatory diseases among patients admitted to internal medicine for aseptic meningitis is not rare (4% of overall aseptic meningitis). The PCR upon admission to the emergency department is obviously of major importance for the prompt optimization of therapy and management. However, meningitis due to

  14. Combating emerging viral threats

    PubMed Central

    Bekerman, Elena; Einav, Shirit

    2015-01-01

    Synopsis Most approved antiviral therapeutics selectively inhibit proteins encoded by a single virus, thereby providing a “one drug-one bug” solution. As a result of this narrow spectrum of coverage and the high cost of drug development, therapies are currently approved for fewer than ten viruses out of the hundreds known to cause human disease. This perspective summarizes progress and challenges in the development of broad-spectrum antiviral therapies. These strategies include targeting enzymatic functions shared by multiple viruses and host cell machinery by newly discovered compounds or by repurposing approved drugs. These approaches offer new practical means for developing therapeutics against existing and emerging viral threats. PMID:25883340

  15. Equine viral arteritis.

    PubMed

    Balasuriya, Udeni B R

    2014-12-01

    Equine arteritis virus (EAV), the causative agent of equine viral arteritis (EVA), is a respiratory and reproductive disease that occurs throughout the world. EAV infection is highly species-specific and exclusively limited to members of the family Equidae, which includes horses, donkeys, mules, and zebras. EVA is an economically important disease and outbreaks could cause significant losses to the equine industry. The primary objective of this article is to summarize current understanding of EVA, specifically the disease, pathogenesis, epidemiology, host immune response, vaccination and treatment strategies, prevention and control measures, and future directions. PMID:25441113

  16. Viral surveillance and discovery

    PubMed Central

    Lipkin, Walter Ian; Firth, Cadhla

    2014-01-01

    The field of virus discovery has burgeoned with the advent of high throughput sequencing platforms and bioinformatics programs that enable rapid identification and molecular characterization of known and novel agents, investments in global microbial surveillance that include wildlife and domestic animals as well as humans, and recognition that viruses may be implicated in chronic as well as acute diseases. Here we review methods for viral surveillance and discovery, strategies and pitfalls in linking discoveries to disease, and identify opportunities for improvements in sequencing instrumentation and analysis, the use of social media and medical informatics that will further advance clinical medicine and public health. PMID:23602435

  17. Complement and Viral Pathogenesis

    PubMed Central

    Stoermer, Kristina A.; Morrison, Thomas E.

    2011-01-01

    The complement system functions as an immune surveillance system that rapidly responds to infection. Activation of the complement system by specific recognition pathways triggers a protease cascade, generating cleavage products that function to eliminate pathogens, regulate inflammatory responses, and shape adaptive immune responses. However, when dysregulated, these powerful functions can become destructive and the complement system has been implicated as a pathogenic effector in numerous diseases, including infectious diseases. This review highlights recent discoveries that have identified critical roles for the complement system in the pathogenesis of viral infection. PMID:21292294

  18. Dual diagnosis: a review of etiological theories.

    PubMed

    Mueser, K T; Drake, R E; Wallach, M A

    1998-01-01

    The etiology of the high prevalence of substance use disorders in patients with severe mental illness (schizophrenia or bipolar disorder) is unclear. We review the evidence of different theories of increased comorbidity, organized according to four general models: common factor models, secondary substance use disorder models, secondary psychiatric disorder models, and bidirectional models. Among common factor models, evidence suggests that antisocial personality disorder accounts for some increased comorbidity. Among secondary substance use disorder models, there is support for the supersensitivity model, which posits that biological vulnerability of psychiatric disorders results in sensitivity to small amounts of alcohol and drugs, leading to substance use disorders. There is minimal support for the self-medication model, but the accumulation of multiple risk factors related to mental illness, including dysphoria, may increase the risk of substance use disorder. Secondary psychiatric disorder models remain to be convincingly demonstrated. Bidirectional models have not been systematically examined. Further clarification of etiologic factors, including the identification of subtypes of dual diagnosis, may have implications for developing more effective prevention efforts and treatment. PMID:9801712

  19. Etiology, diagnosis, and clinical management of vulvodynia

    PubMed Central

    Sadownik, Leslie A

    2014-01-01

    Chronic vulvar pain or discomfort for which no obvious etiology can be found, ie, vulvodynia, can affect up to 16% of women. It may affect girls and women across all age groups and ethnicities. Vulvodynia is a significant burden to society, the health care system, the affected woman, and her intimate partner. The etiology is multifactorial and may involve local injury or inflammation, and peripheral and or central sensitization of the nervous system. An approach to the diagnosis and management of a woman presenting with chronic vulvar pain should address the biological, psychological, and social/interpersonal factors that contribute to her illness. The gynecologist has a key role in excluding other causes for vulvar pain, screening for psychosexual and pelvic floor dysfunction, and collaborating with other health care providers to manage a woman’s pain. An important component of treatment is patient education regarding the pathogenesis of the pain and the negative impact of experiencing pain on a woman’s overall quality of life. An individualized, holistic, and often multidisciplinary approach is needed to effectively manage the woman’s pain and pain-related distress. PMID:24833921

  20. Convergent mechanisms in etiologically-diverse dystonias

    PubMed Central

    Thompson, Valerie B.; Jinnah, H. A.

    2012-01-01

    Introduction Dystonia is a neurological disorder associated with twisting motions and abnormal postures, which compromise normal movements and can be both painful and debilitating. It can affect a single body part (focal), several contiguous regions (segmental), or the entire body (generalized), and can arise as a result of numerous causes, both genetic and acquired. Despite the diversity of causes and manifestations, shared clinical features suggest that common mechanisms of pathogenesis may underlie many dystonias. Areas Covered This review identifies shared themes in etiologically-diverse dystonias on several biological levels. At the cellular level, abnormalities in the dopaminergic system, mitochondrial function, and calcium regulation are discussed. At the anatomical level, the roles of the basal ganglia and the cerebellum in dystonia are described. Global central nervous system dysfunction, with regard to aberrant neuronal plasticity, inhibition, and sensorimotor integration is also discussed. Using clinical data and data from animal models, this article seeks to highlight shared pathways that may be critical in understanding mechanisms and identifying novel therapeutic strategies in dystonia. Expert Opinion Identifying shared features of pathogenesis can provide insight into the biological processes that underlie etiologically-diverse dystonias, and can suggest novel targets for therapeutic intervention that may be effective in a broad group of affected individuals. PMID:22136648

  1. The epidemiology and etiology of azoospermia

    PubMed Central

    Cocuzza, Marcello; Alvarenga, Conrado; Pagani, Rodrigo

    2013-01-01

    The misconception that infertility is typically associated with the female is commonly faced in the management of infertile men. It is uncommon for a patient to present for an infertility evaluation with an abnormal semen analysis report before an extensive female partner workup has been performed. Additionally, a man is usually considered fertile based only on seminal parameters without a physical exam. This behavior may lead to a delay in both the exact diagnosis and in possible specific infertility treatment. Moreover, male factor infertility can result from an underlying medical condition that is often treatable but could possibly be life-threatening. The responsibility of male factor in couple's infertility has been exponentially rising in recent years due to a comprehensive evaluation of reproductive male function and improved diagnostic tools. Despite this improvement in diagnosis, azoospermia is always the most challenging topic associated with infertility treatment. Several conditions that interfere with spermatogenesis and reduce sperm production and quality can lead to azoospermia. Azoospermia may also occur because of a reproductive tract obstruction. Optimal management of patients with azoospermia requires a full understanding of the disease etiology. This review will discuss in detail the epidemiology and etiology of azoospermia. A thorough literature survey was performed using the Medline, EMBASE, BIOSIS, and Cochrane databases. We restricted the survey to clinical publications that were relevant to male infertility and azoospermia. Many of the recommendations included are not based on controlled studies. PMID:23503951

  2. Etiology and therapeutic approach to elevated lactate

    PubMed Central

    Andersen, Lars W.; Mackenhauer, Julie; Roberts, Jonathan C.; Berg, Katherine M.; Cocchi, Michael N.; Donnino, Michael W.

    2014-01-01

    Lactate levels are commonly evaluated in acutely ill patients. Although most commonly used in the context of evaluating shock, lactate can be elevated for many reasons. While tissue hypoperfusion is probably the most common cause of elevation, many other etiologies or contributing factors exist. Clinicians need to be aware of the many potential causes of lactate elevation as the clinical and prognostic importance of an elevated lactate varies widely by disease state. Moreover, specific therapy may need to be tailored to the underlying cause of elevation. The current review is based on a comprehensive PubMed search and contains an overview of the pathophysiology of lactate elevation followed by an in-depth look at the varied etiologies, including medication-related causes. The strengths and weaknesses of lactate as a diagnostic/prognostic tool and its potential use as a clinical endpoint of resuscitation will be discussed. The review ends with some general recommendations on management of patients with elevated lactate. PMID:24079682

  3. The etiology of delayed sleep phase disorder.

    PubMed

    Micic, Gorica; Lovato, Nicole; Gradisar, Michael; Ferguson, Sally A; Burgess, Helen J; Lack, Leon C

    2016-06-01

    According to classification manuals for sleep disorders, nine disorders are directly related to biological clock timing misalignments. Of all, delayed sleep phase disorder (DSPD) is the most commonly diagnosed, predominantly affecting adolescents, young adults, and insomnia patients. It is a persistent inability to fall asleep at earlier, more desirable and socially conventional times, coupled with extreme difficulty awakening in the morning. Considerable evidence shows a delay in the circadian clock to be associated with DSPD. Therefore, treatments have mainly focused on advancing the biological clock and sleep timing through pharmacotherapy, phototherapy and behavioral therapies. The clinical evidence indicates that these treatments are efficacious, at least in the short term. However, follow up studies show frequent patient relapse, leading researchers to speculate that alternative etiologies may be contributing to sleep and circadian clock delays in DSPD. The aim of the present paper is to review and collate current literature related to DSPD etiology in order to outline gaps in current knowledge and suggest future research. PMID:26434674

  4. Human viral gastroenteritis.

    PubMed Central

    Christensen, M L

    1989-01-01

    During the last 15 years, several different groups of fastidious viruses that are responsible for a large proportion of acute viral gastroenteritis cases have been discovered by the electron microscopic examination of stool specimens. This disease is one of the most prevalent and serious clinical syndromes seen around the world, especially in children. Rotaviruses, in the family Reoviridae, and fastidious fecal adenoviruses account for much of the viral gastroenteritis in infants and young children, whereas the small caliciviruses and unclassified astroviruses, and possibly enteric coronaviruses, are responsible for significantly fewer cases overall. In addition to electron microscopy, enzyme immunoassays and other rapid antigen detection systems have been developed to detect rotaviruses and fastidious fecal adenoviruses in the stool specimens of both nonhospitalized patients and those hospitalized for dehydration and electrolyte imbalance. Experimental rotavirus vaccines have also been developed, due to the prevalence and seriousness of rotavirus infection. The small, unclassified Norwalk virus and morphologically similar viruses are responsible for large and small outbreaks of acute gastroenteritis in older children, adolescents, and adults. Hospitalization of older patients infected with these viruses is usually not required, and their laboratory diagnoses have been limited primarily to research laboratories. Images PMID:2644024

  5. [Emergent viral infections].

    PubMed

    Galama, J M

    2001-03-31

    The emergence and re-emergence of viral infections is an ongoing process. Large-scale vaccination programmes led to the eradication or control of some viral infections in the last century, but new viruses are always emerging. Increased travel is leading to a rise in the importation of exotic infections such as dengue and hepatitis E, but also of hepatitis A, which is no longer endemic. Apart from import diseases new viruses have appeared (Nipah-virus and transfusion-transmitted virus). Existing viruses may suddenly cause more severe diseases, e.g. infection by enterovirus 71. The distribution area of a virus may change, e.g. in case of West Nile virus, an Egyptian encephalitis virus that appears to have established itself in the USA. Furthermore, there is no such thing as a completely new virus; it is always an existing virus that has adapted itself to another host or that was already present in humans but has only recently been discovered. A number of factors facilitate the emergence of new infectious diseases. These include intensive animal husbandry and the transport of animals. The unexpected appearance of West Nile virus in the western hemisphere was possibly due to animal transportation. PMID:11305210

  6. Viral infections of rabbits.

    PubMed

    Kerr, Peter J; Donnelly, Thomas M

    2013-05-01

    Viral diseases of rabbits have been used historically to study oncogenesis (e.g. rabbit fibroma virus, cottontail rabbit papillomavirus) and biologically to control feral rabbit populations (e.g. myxoma virus). However, clinicians seeing pet rabbits in North America infrequently encounter viral diseases although myxomatosis may be seen occasionally. The situation is different in Europe and Australia, where myxomatosis and rabbit hemorrhagic disease are endemic. Advances in epidemiology and virology have led to detection of other lapine viruses that are now recognized as agents of emerging infectious diseases. Rabbit caliciviruses, related to rabbit hemorrhagic disease, are generally avirulent, but lethal variants are being identified in Europe and North America. Enteric viruses including lapine rotavirus, rabbit enteric coronavirus and rabbit astrovirus are being acknowledged as contributors to the multifactorial enteritis complex of juvenile rabbits. Three avirulent leporid herpesviruses are found in domestic rabbits. A fourth highly pathogenic virus designated leporid herpesvirus 4 has been described in Canada and Alaska. This review considers viruses affecting rabbits by their clinical significance. Viruses of major and minor clinical significance are described, and viruses of laboratory significance are mentioned. PMID:23642871

  7. Viral noncoding RNAs: more surprises

    PubMed Central

    Tycowski, Kazimierz T.; Guo, Yang Eric; Lee, Nara; Moss, Walter N.; Vallery, Tenaya K.; Xie, Mingyi

    2015-01-01

    Eukaryotic cells produce several classes of long and small noncoding RNA (ncRNA). Many DNA and RNA viruses synthesize their own ncRNAs. Like their host counterparts, viral ncRNAs associate with proteins that are essential for their stability, function, or both. Diverse biological roles—including the regulation of viral replication, viral persistence, host immune evasion, and cellular transformation—have been ascribed to viral ncRNAs. In this review, we focus on the multitude of functions played by ncRNAs produced by animal viruses. We also discuss their biogenesis and mechanisms of action. PMID:25792595

  8. Detection of viral hemorrhagic septicemia virus

    USGS Publications Warehouse

    Winton, James; Kurath, Gael; Batts, William

    2007-01-01

    Viral hemorrhagic septicemia virus (VHSV) is considered to be one of the most important viral pathogens of finfish and is listed as reportable by many nations and international organizations (Office International des Epizooties 2006). Prior to 1988, VHSV was thought to be limited to Europe (Wolf 1988; Smail 1999). Subsequently, it was shown that the virus is endemic among many marine and anadromous fish species in both the Pacific and Atlantic Oceans (Meyers and Winton 1995; Skall et al. 2005). Genetic analysis reveals that isolates of VHSV can be divided into four genotypes that generally correlate with geographic location with the North American isolates generally falling into VHSV Genotype IV (Snow et al. 2004). In 2005-2006, reports from the Great Lakes region indicated that wild fish had experienced disease or, in some cases, very large die-offs from VHSV (Elsayed et al. 2006, Lumsden et al. 2007). The new strain from the Great Lakes, now identified as VHSV Genotype IVb, appears most closely related to isolates of VHSV from mortalities that occurred during 2000-2004 in rivers and near-shore areas of New Brunswick and Nova Scotia, Canada (Gagne et al. 2007). The type IVb isolate found in the Great Lakes region is the only strain outside of Europe that has been associated with significant mortality in freshwater species.

  9. Immunogenicity of viral B-cell epitopes inserted into two surface loops of the Escherichia coli K12 LamB protein and expressed in an attenuated aroA strain of Salmonella typhimurium.

    PubMed

    Wang, J; Michel, V; Leclerc, C; Hofnung, M; Charbit, A

    1999-01-01

    We previously developed a general procedure which allows the genetic coupling of a chosen foreign linear epitope in different 'permissive' sites of a carrier protein. By using the outer membrane protein LamB of Escherichia coli K12 as a carrier, we were able to express a number of different foreign epitopes at the bacterial surface. In the present work, taking advantage of the recent determination of the crystal structure of LamB, we inserted two model B-cell epitopes i.e.--the C3 epitope from poliovirus (residues 93 to 103 of VP1) and the preS2 epitope from hepatitis B virus, (residues 132 to 145)--at the tip of the most distal and largest surface exposed region of LamB (after residues 386, into loop L9). We also used two previously constructed LamB hybrids, corresponding to the insertion of the C3B or preSB epitope into permissive site 153 (lying in the middle of the fourth surface loop of LamB), to construct two LamB proteins corresponding to the simultaneous insertion of the two different epitopes (with one epitope per site). The LamB hybrids were placed under the control of the anaerobically inducible pnirB promoter and expressed in a LamB-negative derivative of the aroA attenuated strain of S. typhimurium, SL3261. In vitro, the recombinant proteins were expressed at a high level (up to 10% of whole cell proteins) and in vivo the recombinant plasmids were stably maintained. For both epitopes, genetic coupling at site 386 appeared to be more favorable for the induction of anti-epitope antibodies than coupling at site 153. Moreover, the LamB hybrid corresponding to the simultaneous insertion of the preSB epitope at site 153 and of the C3B epitope at site 386 allowed the induction of both anti-poliovirus and anti-hepatitis B antibodies. PMID:10078601

  10. Nuclear targeting of viral and non-viral DNA.

    PubMed

    Chowdhury, E H

    2009-07-01

    The nuclear envelope presents a major barrier to transgene delivery and expression using a non-viral vector. Virus is capable of overcoming the barrier to deliver their genetic materials efficiently into the nucleus by virtue of the specialized protein components with the unique amino acid sequences recognizing cellular nuclear transport machinery. However, considering the safety issues in the clinical gene therapy for treating critical human diseases, non-viral systems are highly promising compared with their viral counterparts. This review summarizes the progress on exploring the nuclear traffic mechanisms for the prominent viral vectors and the technological innovations for the nuclear delivery of non-viral DNA by mimicking those natural processes evolved for the viruses as well as for many cellular proteins. PMID:19552613

  11. Human Sentinel Surveillance of Influenza and Other Respiratory Viral Pathogens in Border Areas of Western Cambodia.

    PubMed

    Timmermans, Ans; Melendrez, Melanie C; Se, Youry; Chuang, Ilin; Samon, Nou; Uthaimongkol, Nichapat; Klungthong, Chonticha; Manasatienkij, Wudtichai; Thaisomboonsuk, Butsaya; Tyner, Stuart D; Rith, Sareth; Horm, Viseth Srey; Jarman, Richard G; Bethell, Delia; Chanarat, Nitima; Pavlin, Julie; Wongstitwilairoong, Tippa; Saingam, Piyaporn; El, But Sam; Fukuda, Mark M; Touch, Sok; Sovann, Ly; Fernandez, Stefan; Buchy, Philippe; Chanthap, Lon; Saunders, David

    2016-01-01

    Little is known about circulation of influenza and other respiratory viruses in remote populations along the Thai-Cambodia border in western Cambodia. We screened 586 outpatients (median age 5, range 1-77) presenting with influenza-like-illness (ILI) at 4 sentinel sites in western Cambodia between May 2010 and December 2012. Real-time reverse transcriptase (rRT) PCR for influenza was performed on combined nasal and throat specimens followed by viral culture, antigenic analysis, antiviral susceptibility testing and full genome sequencing for phylogenetic analysis. ILI-specimens negative for influenza were cultured, followed by rRT-PCR for enterovirus and rhinovirus (EV/RV) and EV71. Influenza was found in 168 cases (29%) and occurred almost exclusively in the rainy season from June to November. Isolated influenza strains had close antigenic and phylogenetic relationships, matching vaccine and circulating strains found elsewhere in Cambodia. Influenza vaccination coverage was low (<20%). Western Cambodian H1N1(2009) isolate genomes were more closely related to 10 earlier Cambodia isolates (94.4% genome conservation) than to 13 Thai isolates (75.9% genome conservation), despite sharing the majority of the amino acid changes with the Thai references. Most genes showed signatures of purifying selection. Viral culture detected only adenovirus (5.7%) and parainfluenza virus (3.8%), while non-polio enteroviruses (10.3%) were detected among 164 culture-negative samples including coxsackievirus A4, A6, A8, A9, A12, B3, B4 and echovirus E6 and E9 using nested RT-PCR methods. A single specimen of EV71 was found. Despite proximity to Thailand, influenza epidemiology of these western Cambodian isolates followed patterns observed elsewhere in Cambodia, continuing to support current vaccine and treatment recommendations from the Cambodian National Influenza Center. Amino acid mutations at non-epitope sites, particularly hemagglutinin genes, require further investigation in light

  12. Human Sentinel Surveillance of Influenza and Other Respiratory Viral Pathogens in Border Areas of Western Cambodia

    PubMed Central

    Chuang, Ilin; Samon, Nou; Uthaimongkol, Nichapat; Klungthong, Chonticha; Manasatienkij, Wudtichai; Thaisomboonsuk, Butsaya; Tyner, Stuart D.; Rith, Sareth; Horm, Viseth Srey; Jarman, Richard G.; Bethell, Delia; Chanarat, Nitima; Pavlin, Julie; Wongstitwilairoong, Tippa; Saingam, Piyaporn; El, But Sam; Fukuda, Mark M.; Touch, Sok; Sovann, Ly; Fernandez, Stefan; Buchy, Philippe; Chanthap, Lon; Saunders, David

    2016-01-01

    Little is known about circulation of influenza and other respiratory viruses in remote populations along the Thai-Cambodia border in western Cambodia. We screened 586 outpatients (median age 5, range 1–77) presenting with influenza-like-illness (ILI) at 4 sentinel sites in western Cambodia between May 2010 and December 2012. Real-time reverse transcriptase (rRT) PCR for influenza was performed on combined nasal and throat specimens followed by viral culture, antigenic analysis, antiviral susceptibility testing and full genome sequencing for phylogenetic analysis. ILI-specimens negative for influenza were cultured, followed by rRT-PCR for enterovirus and rhinovirus (EV/RV) and EV71. Influenza was found in 168 cases (29%) and occurred almost exclusively in the rainy season from June to November. Isolated influenza strains had close antigenic and phylogenetic relationships, matching vaccine and circulating strains found elsewhere in Cambodia. Influenza vaccination coverage was low (<20%). Western Cambodian H1N1(2009) isolate genomes were more closely related to 10 earlier Cambodia isolates (94.4% genome conservation) than to 13 Thai isolates (75.9% genome conservation), despite sharing the majority of the amino acid changes with the Thai references. Most genes showed signatures of purifying selection. Viral culture detected only adenovirus (5.7%) and parainfluenza virus (3.8%), while non-polio enteroviruses (10.3%) were detected among 164 culture-negative samples including coxsackievirus A4, A6, A8, A9, A12, B3, B4 and echovirus E6 and E9 using nested RT-PCR methods. A single specimen of EV71 was found. Despite proximity to Thailand, influenza epidemiology of these western Cambodian isolates followed patterns observed elsewhere in Cambodia, continuing to support current vaccine and treatment recommendations from the Cambodian National Influenza Center. Amino acid mutations at non-epitope sites, particularly hemagglutinin genes, require further investigation in light

  13. Functional Role of Infective Viral Particles on Metal Reduction

    SciTech Connect

    Coates, John D.

    2014-04-01

    A proposed strategy for the remediation of uranium (U) contaminated sites was based on the immobilization of U by reducing the oxidized soluble U, U(VI), to form a reduced insoluble end product, U(IV). Previous studies identified Geobacter sp., including G. sulfurreducens and G. metallireducens, as predominant U(VI)-reducing bacteria under acetate-oxidizing and U(VI)-reducing conditions. Examination of the finished genome sequence annotation of the canonical metal reducing species Geobacter sulfurreducens strain PCA and G. metallireduceans strain GS-15 as well as the draft genome sequence of G. uraniumreducens strain Rf4 identified phage related proteins. In addition, the completed genome for Anaeromyxobacter dehalogenans and the draft genome sequence of Desulfovibrio desulfuricans strain G20, two more model metal-reducing bacteria, also revealed phage related sequences. The presence of these gene sequences indicated that Geobacter spp., Anaeromyxobacter spp., and Desulfovibrio spp. are susceptible to viral infection. Furthermore, viral populations in soils and sedimentary environments in the order of 6.4×10{sup 6}–2.7×10{sup 10} VLP’s cm{sup -3} have been observed. In some cases, viral populations exceed bacterial populations in these environments suggesting that a relationship may exist between viruses and bacteria. Our preliminary screens of samples collected from the ESR FRC indicated that viral like particles were observed in significant numbers. The objective of this study was to investigate the potential functional role viruses play in metal reduction specifically Fe(III) and U(VI) reduction, the environmental parameters affecting viral infection of metal reducing bacteria, and the subsequent effects on U transport.

  14. Immune Responses to Circulating and Vaccine Viral Strains in HIV-Infected and Uninfected Children and Youth Who Received the 2013/2014 Quadrivalent Live-Attenuated Influenza Vaccine

    PubMed Central

    Weinberg, Adriana; Curtis, Donna; Ning, Mariangeli Freitas; Claypool, David Jeremy; Jalbert, Emilie; Patterson, Julie; Frank, Daniel N.; Ir, Diana; Armon, Carl

    2016-01-01

    to LAIV4. In conclusion, HIV-infected and uninfected children and youth had comparable responses to LAIV4. H1N1-09 immune responses were lower than BY and higher than H1N1-14, suggesting that both antigenic mismatches between circulating and vaccine H1N1 and lower immunogenicity of the H1N1 vaccine strain may have contributed to the decreased H1N1 effectiveness of 2013–2014 LAIV4. PMID:27148262

  15. Dengue viral infections

    PubMed Central

    Malavige, G; Fernando, S; Fernando, D; Seneviratne, S

    2004-01-01

    Dengue viral infections are one of the most important mosquito borne diseases in the world. They may be asymptomatic or may give rise to undifferentiated fever, dengue fever, dengue haemorrhagic fever (DHF), or dengue shock syndrome. Annually, 100 million cases of dengue fever and half a million cases of DHF occur worldwide. Ninety percent of DHF subjects are children less than 15 years of age. At present, dengue is endemic in 112 countries in the world. No vaccine is available for preventing this disease. Early recognition and prompt initiation of appropriate treatment are vital if disease related morbidity and mortality are to be limited. This review outlines aspects of the epidemiology of dengue infections, the dengue virus and its mosquito vector, clinical features and pathogenesis of dengue infections, and the management and control of these infections. PMID:15466994

  16. [Update chronic viral hepatitis].

    PubMed

    Ziegenhagen, D J

    2016-03-01

    More than 500,000 people in Germany have chronic viral hepatitis. The interferon-based treatments formerly used in hepatitis B have been widely replaced by life-long oral medication with nucleoside or nucleotide analogues. Treatment for chronic hepatitis C has been improved substantially by the development of new and very expensive drug combinations. Up to 90% of patients can now be cured with certainty, and one to two years after successful treatment there is no relevant risk of recurrence. These individuals expect to receive insurance cover under appropriate conditions. Vaccination programmes are very efficient at decreasing the incidence of hepatitis B, but no vaccine against hepatitis C is likely to become available in the next decade. PMID:27111951

  17. Viral Hemorrhagic Fever Diagnostics.

    PubMed

    Racsa, Lori D; Kraft, Colleen S; Olinger, Gene G; Hensley, Lisa E

    2016-01-15

    There are 4 families of viruses that cause viral hemorrhagic fever (VHF), including Filoviridae. Ebola virus is one virus within the family Filoviridae and the cause of the current outbreak of VHF in West Africa. VHF-endemic areas are found throughout the world, yet traditional diagnosis of VHF has been performed in large reference laboratories centered in Europe and the United States. The large amount of capital needed, as well as highly trained and skilled personnel, has limited the availability of diagnostics in endemic areas except in conjunction with governmental and nongovernmental entities. However, rapid diagnosis of VHF is essential to efforts that will limit outbreaks. In addition, increased global travel suggests VHF diagnoses may be made outside of the endemic areas. Thus, understanding how to diagnose VHF is imperative for laboratories worldwide. This article reviews traditional and current diagnostic modalities for VHF. PMID:26354968

  18. Viral Quasispecies Evolution

    PubMed Central

    Sheldon, Julie; Perales, Celia

    2012-01-01

    Summary: Evolution of RNA viruses occurs through disequilibria of collections of closely related mutant spectra or mutant clouds termed viral quasispecies. Here we review the origin of the quasispecies concept and some biological implications of quasispecies dynamics. Two main aspects are addressed: (i) mutant clouds as reservoirs of phenotypic variants for virus adaptability and (ii) the internal interactions that are established within mutant spectra that render a virus ensemble the unit of selection. The understanding of viruses as quasispecies has led to new antiviral designs, such as lethal mutagenesis, whose aim is to drive viruses toward low fitness values with limited chances of fitness recovery. The impact of quasispecies for three salient human pathogens, human immunodeficiency virus and the hepatitis B and C viruses, is reviewed, with emphasis on antiviral treatment strategies. Finally, extensions of quasispecies to nonviral systems are briefly mentioned to emphasize the broad applicability of quasispecies theory. PMID:22688811

  19. Chronic fatigue syndrome. 1: Etiology and pathogenesis.

    PubMed

    Farrar, D J; Locke, S E; Kantrowitz, F G

    1995-01-01

    Chronic fatigue syndrome (CFS) is a disorder of unknown etiology characterized by debilitating fatigue and other somatic and neuropsychiatric symptoms. A range of heterogeneous clinical and laboratory findings have been reported in patients with CFS. Various theories have been proposed to explain the underlying pathophysiologic processes but none has been proved. Research findings of immunologic dysfunction and neuroendocrine changes suggest the possible dysregulation of interactions between the nervous system and the immune system. Without a clear understanding of its etiopathogenesis, CFS has no definitive treatment. Management approaches have been necessarily speculative, and they have evolved separately in a number of medical and nonmedical disciplines. The results of several controlled treatment studies have been inconclusive. An accurate case definition identifying homogeneous subtypes of CFS is needed. The integration of medical and psychologic treatment modalities and the use of both biologic and psychologic markers to evaluate treatment response will enhance future treatment strategies. PMID:7579775

  20. Etiological analysis of presumed perinatal stroke.

    PubMed

    Kocaman, Canan; Yilmaz, Yuksel

    2012-02-01

    This study aimed to investigate the maternal, pre- and perinatal, and prothrombotic factors with congenital hemiparesis due to presumed perinatal stroke (PPS). Prothrombotic risk factors including protein C and S, antithrombin III, lipoprotein (a), homocystein, factor VIII levels; anticardiolipin antibodies and lupus anticoagulant; methylenetetrahydrofolate reductase mutations, factor V Leiden, prothrombin G20210A mutations were investigated. Arterial ischemic stroke was detected in 60% and periventricular venous infarction in 40%. At least one prothrombotic risk factor was present in 69%, two in 17%, and three or more in 8.5% of cases. The most common combination was methylenetetrahydrofolate reductase C677T and factor V Leiden heterozygosity. The etiology and pathogenesis of PPS is still unclear. According to this study, most of the patients with PPS might have one or more prothrombotic risk factors and certain prenatal risk factors including intrauterine growth retardation, twin gestation and preeclampsia might be related to PPS. PMID:21561729

  1. Pulmonary vein stenosis: Etiology, diagnosis and management.

    PubMed

    Pazos-López, Pablo; García-Rodríguez, Cristina; Guitián-González, Alba; Paredes-Galán, Emilio; Álvarez-Moure, María Ángel De La Guarda; Rodríguez-Álvarez, Marta; Baz-Alonso, José Antonio; Teijeira-Fernández, Elvis; Calvo-Iglesias, Francisco Eugenio; Íñiguez-Romo, Andrés

    2016-01-26

    Pulmonary vein stenosis (PVS) is rare condition characterized by a challenging diagnosis and unfavorable prognosis at advance stages. At present, injury from radiofrequency ablation for atrial fibrillation has become the main cause of the disease. PVS is characterized by a progressive lumen size reduction of one or more pulmonary veins that, when hemodynamically significant, may raise lobar capillary pressure leading to signs and symptoms such as shortness of breath, cough, and hemoptysis. Image techniques (transesophageal echocardiography, computed tomography, magnetic resonance and perfusion imaging) are essential to reach a final diagnosis and decide an appropriate therapy. In this regard, series from referral centers have shown that surgical and transcatheter interventions may improve prognosis. The purpose of this article is to review the etiology, assessment and management of PVS. PMID:26839659

  2. Congenital Vertical Talus: Etiology and Management.

    PubMed

    Miller, Mark; Dobbs, Matthew B

    2015-10-01

    Congenital vertical talus is a rare foot deformity. If left untreated, it causes significant disability, including pain and functional limitations. Although the etiology of vertical talus is likely heterogeneous, recent evidence strongly supports a genetic cause linking it to genes expressed during early limb development. Traditional management for vertical talus involves extensive surgeries that are associated with significant short- and long-term complications. A minimally invasive approach that relies on serial manipulation and casting to achieve most of the correction has been shown to produce excellent short-term results with regard to clinical and radiographic correction in both isolated and nonisolated cases of vertical talus. Although long-term studies are needed, achieving correction without extensive surgery may lead to more flexible and functional feet, much as Ponseti method has done for clubfeet. PMID:26337950

  3. Yersinia pestis--etiologic agent of plague.

    PubMed Central

    Perry, R D; Fetherston, J D

    1997-01-01

    Plague is a widespread zoonotic disease that is caused by Yersinia pestis and has had devastating effects on the human population throughout history. Disappearance of the disease is unlikely due to the wide range of mammalian hosts and their attendant fleas. The flea/rodent life cycle of Y. pestis, a gram-negative obligate pathogen, exposes it to very different environmental conditions and has resulted in some novel traits facilitating transmission and infection. Studies characterizing virulence determinants of Y. pestis have identified novel mechanisms for overcoming host defenses. Regulatory systems controlling the expression of some of these virulence factors have proven quite complex. These areas of research have provide new insights into the host-parasite relationship. This review will update our present understanding of the history, etiology, epidemiology, clinical aspects, and public health issues of plague. PMID:8993858

  4. [The deaf child: anatomy, etiologies and management].

    PubMed

    Elmaleh-Bergès, M; Van Den Abbeele, T

    2006-11-01

    Temporal bone imaging in children shows radioanatomical aspects and diseases distinct from the imaging and pathology results found in adults. Imaging modalities such as CT and MR bring out these differences. The aim of this study is to present the CT and MR particularities of the temporal bone during postnatal growth. The mastoid air cells form mostly in the postnatal period and the course of pneumatization is directly correlated with middle ear successive inflammatory episodes. The most frequent etiologies of hearing loss in children are reviewed, emphasizing their specificities in clinical presentation, radiological aspects, and treatment. In children, conductive hearing loss with normal tympanic membrane is mostly caused by minor aplasia rather than otosclerosis. Sensorineural hearing loss, even when unilateral, is predominantly due to malformation or infection and in rare cases to posterior fossa tumor. PMID:17124480

  5. Fecal Incontinence: Etiology, Evaluation, and Treatment

    PubMed Central

    Hayden, Dana M.; Weiss, Eric G.

    2011-01-01

    Fecal incontinence is a debilitating problem facing ~2.2% of the U.S. general population over 65 years of age. Etiologic factors include traumatic, neurologic, congenital, and iatrogenic. Most commonly, obstetric trauma causes fecal incontinence as well as poorly performed anorectal surgery or pelvic radiation. Several severity scores and quality of life indexes have been developed to quantify incontinent symptoms. There are several nonsurgical and surgical options for the treatment of fecal incontinence. Biofeedback is among the most successful nonoperative strategies. Depending on the cause, anal sphincter repair, artificial bowel sphincter, and sacral nerve stimulation are used to treat fecal incontinence with some success. Unfortunately, fecal incontinence is an extremely difficult problem to manage: there has not been one, single treatment option that has proven to be both safe and effective in long-term studies. PMID:22379407

  6. Pulmonary vein stenosis: Etiology, diagnosis and management

    PubMed Central

    Pazos-López, Pablo; García-Rodríguez, Cristina; Guitián-González, Alba; Paredes-Galán, Emilio; Álvarez-Moure, María Ángel De La Guarda; Rodríguez-Álvarez, Marta; Baz-Alonso, José Antonio; Teijeira-Fernández, Elvis; Calvo-Iglesias, Francisco Eugenio; Íñiguez-Romo, Andrés

    2016-01-01

    Pulmonary vein stenosis (PVS) is rare condition characterized by a challenging diagnosis and unfavorable prognosis at advance stages. At present, injury from radiofrequency ablation for atrial fibrillation has become the main cause of the disease. PVS is characterized by a progressive lumen size reduction of one or more pulmonary veins that, when hemodynamically significant, may raise lobar capillary pressure leading to signs and symptoms such as shortness of breath, cough, and hemoptysis. Image techniques (transesophageal echocardiography, computed tomography, magnetic resonance and perfusion imaging) are essential to reach a final diagnosis and decide an appropriate therapy. In this regard, series from referral centers have shown that surgical and transcatheter interventions may improve prognosis. The purpose of this article is to review the etiology, assessment and management of PVS. PMID:26839659

  7. Etiology of breast cancer. II. Epidemiologic aspects *

    PubMed Central

    Vakil, Damodar V.; Morgan, Robert W.

    1973-01-01

    The epidemiology of breast cancer is reviewed with particular emphasis on its etiology. A number of studies suggest that differences in breast cancer incidence are associated with differences in marital status, number of pregnancies, age at menarche, age at menopause, height and weight, socioeconomic status, geographic location and residence. However, in no case is the evidence adequate to establish a “cause and effect” relationship. The genetic component of these associations may be of primary importance, while other conditions such as marital status are probably indirect reflections of the operation of more fundamental factors. There is a general consensus that endocrine factors play an important part in mammary cancer occurrence. At present, the association between breast cancer and the presence of the virus-like (type B) particles in human milk is not established. PMID:4353980

  8. Perspectives on the etiology of Alzheimer's disease

    SciTech Connect

    Mozar, H.N.; Bal, D.G.; Howard, J.T.

    1987-03-20

    There is a lack of consensus among investigators concerning the etiology of Alzheimer's disease. Clues are lacking, however, and the authors have assessed them in a broad biologic context. This inquiry has led us to regard Alzheimer's disease as a multifactorial disorder in which a putative infective agent is an essential element. Despite seeming competition among current hypotheses, there is overall unity. The concept that Down's syndrome is a congenital form of Alzheimer's disease and that both conditions are the result of a ubiquitous infective pathogen that affects genetically susceptible individuals offers the broadest unification. In both conditions slow infections develops against the background of aging. Indirect evidence involving immunologic and other biologic phenomena supports the postulated infectious origin. Overlapping pathologic and clinical features of Alzheimer's disease and the known transmissible encephalopathies suggest a similar pathogenesis.

  9. The many etiologies of neonatal hypocalcemic seizures.

    PubMed

    Levy-Shraga, Yael; Dallalzadeh, Keren; Stern, Keren; Paret, Gideon; Pinhas-Hamiel, Orit

    2015-03-01

    Seizures during the neonatal period have a broad differential diagnosis. Unlike in developing countries where hypovitaminosis D and hypocalcemia constitutes a major cause of infantile seizures, the number of neonatal seizures attributed to hypocalcemia in developed countries has decreased dramatically due to the improvement of infant formulas and vitamin D supplementation. In these countries, most infants that present with hypocalcemic seizures have underlying endocrinological etiologies rather than dietary insufficiencies. Here, we describe 3 cases of neonatal seizures due to hypocalcemia. Although the symptoms and calcium concentrations at presentation were similar in all 3 cases, the course of the disease and the final diagnosis for each were distinct. The cases are presented along with a brief review of the pathophysiology, differential diagnosis, and treatment of neonatal hypocalcemia. PMID:25738238

  10. Etiologic analysis of 100 anatomically failed dacryocystorhinostomies

    PubMed Central

    Dave, Tarjani Vivek; Mohammed, Faraz Ali; Ali, Mohammad Javed; Naik, Milind N

    2016-01-01

    Background The aim of this study was to assess the etiological factors contributing to the failure of a dacryocystorhinostomy (DCR). Patients and methods Retrospective review was performed in 100 consecutive patients who were diagnosed with anatomically failed DCR at presentation to a tertiary care hospital over a 5-year period from 2010 to 2015. Patient records were reviewed for demographic data, type of past surgery, preoperative endoscopic findings, previous use of adjuvants such as intubation and mitomycin C, and intraoperative notes during the re-revision. The potential etiological factors for failure were noted. Results Of the 100 patients with failed DCRs, the primary surgery was an external DCR in 73 and endoscopic DCR in 27 patients. Six patients in each group had multiple revisions. The mean ages at presentation in the external and endoscopic groups were 39.41 years and 37.19 years, respectively. All patients presented with epiphora. The most common causes of failure were inadequate osteotomy (69.8% in the external group and 85.1% in the endoscopic group, P=0.19) followed by inadequate or inappropriate sac marsupialization (60.2% in the external group and 77.7% in the endoscopic group, P=0.16) and cicatricial closure of the ostium (50.6% in the external group and 55.5% in the endoscopic group, P=0.83). The least common causes such as ostium granulomas and paradoxical middle turbinate (1.37%, n=1) were noted in the external group only. Conclusion Inadequate osteotomy, incomplete sac marsupialization, and cicatricial closure of the ostium were the most common causes of failure and did not significantly differ in the external and endoscopic groups. Meticulous evaluation to identify causative factors for failure and addressing them are crucial for subsequent successful outcomes. PMID:27555748