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Sample records for bk virus

  1. [BK virus infections in kidney transplantation].

    Science.gov (United States)

    Lanot, Antoine; Bouvier, Nicolas; Chatelet, Valérie; Dina, Julia; Béchade, Clémence; Ficheux, Maxence; Henri, Patrick; Lobbedez, Thierry; Hurault de Ligny, Bruno

    2016-04-01

    BK virus is near ubiquitous, with a seroprevalence of around 80% in the general population. Subsequent to an asymptomatic primary infection, BK virus then remains dormant in healthy subjects. Reactivation occurs in immunocompromised people. BKv is pathogenic mainly among patients who have received a kidney transplant, in whom the virus can cause specific tubulo-interstitial nephritis and even result in graft failure among approximately 20 to 30% of nephritic cases. Since the mid 90s, incidence has increased with the use of new powerful immunosuppressor treatments. The cornerstone of BK virus infection or BK virus-associated nephropathy treatment is a decrease of the immunosuppressive regimen, which must then be offset with the risk of rejection. The use of several adjuvant therapies has been submitted (fluoroquinolones, leflunomide, intravenous immunoglobulins, cidofovir), with no sufficient proof enabling the recommendation of first-line prescription. The high frequency of this infection and its potential harmfulness argue for the use of prevention strategies, at least among patients presenting risk factors. Retransplantation is safe after a first kidney allograft loss caused by BK-virus nephropathy, on condition that a screening for viremia is frequently conducted. PMID:26827190

  2. Association of renal adenocarcinoma and BK virus nephropathy post transplantation.

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    Kausman, Joshua Yehuda; Somers, Gino Rene; Francis, David Michael; Jones, Colin Lindsay

    2004-04-01

    While most BK virus infections are asymptomatic, immunosuppression has been associated with BK virus reactivation and impaired graft function or ureteric ulceration in renal transplant patients and hemorrhagic cystitis in bone marrow transplant patients. Oncogenicity is also postulated and this is the first report of a child with a carcinoma of the donor renal pelvis following BK virus allograft nephropathy. Removal of the primary tumor and cessation of immunosuppression led to regression of secondary tumors and a return to health. PMID:14986088

  3. Polyomavirus specific cellular immunity: from BK-virus-specific cellular immunity to BK-virus-associated nephropathy ?

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    manon edekeyser

    2015-06-01

    Full Text Available In renal transplantation, BK-virus-associated nephropathy has emerged as a major complication, with a prevalence of 5–10% and graft loss in >50% of cases. BK-virus is a member of the Polyomavirus family and rarely induces apparent clinical disease in the general population. However, replication of polyomaviruses, associated with significant organ disease, is observed in patients with acquired immunosuppression, which suggests a critical role for virus-specific cellular immunity to control virus replication and prevent chronic disease. Monitoring of specific immunity combined with viral load could be used to individually assess the risk of viral reactivation and virus control. We review the current knowledge on BK-virus specific cellular immunity and, more specifically, in immunocompromised patients. In the future, immune-based therapies could allow us to treat and prevent BK-virus-associated nephropathy.

  4. BK virus infection in a renal transplant Saudi child

    International Nuclear Information System (INIS)

    BK human polyomavirus (BKV) causes an asymptomatic primary infection in children, but later, establishes latency mainly in the urinary tract. Virus-host interactions influencing persistence and pathogenicity are not well-understood. We present here a 12-year-old Saudi boy, who had renal transplant in Egypt. Seven months later, he was admitted to our Pediatric Nephrology Unit as a case of renal impairment. He developed BKV infection, diagnosed and successfully managed in our hospital. This case demonstrates the expanding clinical importance of BKV in a post renal transplant patient. This virus can be detected in transitional cells in the urine (decoy cells) using cytology. Testing for BKV deoxyribonucleic acid in urine and blood is an early detection assay, and can be used as a screening test in the early stages. The early reduction of immunosuppression can improve the prognosis. No specific antiviral treatment has been established yet. This is the first report of detecting BK virus in a Saudi post-transplant child in urine and blood specimens by using polymerase chain reaction. (author)

  5. BK virus-associated hemorrhagic cystitis after pediatric stem cell transplantation.

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    Han, Seung Beom; Cho, Bin; Kang, Jin Han

    2014-12-01

    Hemorrhagic cystitis is a common stem cell transplantation-related complication. The incidence of early-onset hemorrhagic cystitis, which is related to the pretransplant conditioning regimen, has decreased with the concomitant use of mesna and hyperhydration. However, late-onset hemorrhagic cystitis, which is usually caused by the BK virus, continues to develop. Although the BK virus is the most common pathogenic microorganism of poststem cell transplantation late-onset hemorrhagic cystitis, pediatricians outside the hemato-oncology and nephrology specialties tend to be unfamiliar with hemorrhagic cystitis and the BK virus. Moreover, no standard guidelines for the early diagnosis and treatment of BK virus-associated hemorrhagic cystitis after stem cell transplantation have been established. Here, we briefly introduce poststem cell transplantation BK virus-associated hemorrhagic cystitis. PMID:25653684

  6. BK virus-associated hemorrhagic cystitis after pediatric stem cell transplantation

    OpenAIRE

    Han, Seung Beom; Cho, Bin; Kang, Jin Han

    2014-01-01

    Hemorrhagic cystitis is a common stem cell transplantation-related complication. The incidence of early-onset hemorrhagic cystitis, which is related to the pretransplant conditioning regimen, has decreased with the concomitant use of mesna and hyperhydration. However, late-onset hemorrhagic cystitis, which is usually caused by the BK virus, continues to develop. Although the BK virus is the most common pathogenic microorganism of poststem cell transplantation late-onset hemorrhagic cystitis, ...

  7. No Evidence for Infection of UK Prostate Cancer Patients with XMRV, BK Virus, Trichomonas vaginalis or Human Papilloma Viruses

    OpenAIRE

    Groom, Harriet C. T.; Warren, Anne Y; David E Neal; Kate N Bishop

    2012-01-01

    The prevalence of specific infections in UK prostate cancer patients was investigated. Serum from 84 patients and 62 controls was tested for neutralisation of xenotropic murine leukaemia virus-related virus (XMRV) Envelope. No reactivity was found in the patient samples. In addition, a further 100 prostate DNA samples were tested for XMRV, BK virus, Trichomonas vaginalis and human papilloma viruses by nucleic acid detection techniques. Despite demonstrating DNA integrity and assay sensitivity...

  8. Activities of Different Classes of Acyclic Nucleoside Phosphonates against BK Virus in Primary Human Renal Cells

    Czech Academy of Sciences Publication Activity Database

    Topalis, D.; Lebeau, I.; Krečmerová, Marcela; Andrei, G.; Snoeck, R.

    2011-01-01

    Roč. 55, č. 5 (2011), s. 1961-1967. ISSN 0066-4804 Institutional research plan: CEZ:AV0Z40550506 Keywords : polyomavirus * BK virus * nephropathy * acyclic nucleoside phosphonates * HPMP-5-azaC Subject RIV: CC - Organic Chemistry Impact factor: 4.841, year: 2011

  9. Diagnóstico y clasificación molecular del virus BK en receptores de trasplante renal

    OpenAIRE

    Riva, Omar; Cobos, Marisa; Clemente, J

    2010-01-01

    La infección primaria por virus BK ocurre durante la infancia permaneciendo latente en el tracto urogenital. En individuos que presentan alteraciones en la inmunidad celular, el virus se reactiva haciendo posible su detección en orina y sangre. En receptores de trasplante renal, la nefropatía producida por el virus BK puede llevar a la pérdida de la función del injerto. El virus BK es miembro de la familia Polyomaviridae, presenta un genoma de ADN circular doble cadena unido en forma covalent...

  10. Electron microscopic features of a brain tumor induced in hamster by BK virus, a human papova virus.

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    Tsuboi,Masahiro

    1979-12-01

    Full Text Available In order to locate the target cells for malignant transformation by BK virus (a human papova virus in hamster brain, electron microscopic observation of tumor originally induced in hamster brain by BK virus was performed. With light microscopy, the BK virus-induced tumor (Vn 17 bore a close resemblance to human malignant ependymoma. Under the electron microscope, numerous microvilli and few cilia were visible on the surface of the tumor cells. These tumor cells were joined to each other by desmosomes. Gap junctions were not observed. Multilayered cuboidal cells were observed around the lumen and blood vessels in the tumor. With regard to fine structure, three types of Vn 17 cells were recognized; ependymal like cells, tanycytes with prominent cell processes, and undifferentiated cells with few cytoplasmic organelles. There was no basal lamina between the ependymal cells and the connective tissue stroma. The Vn 17 cells showed some similarity to the ultrastructural features of the epemdymal cells of newborn rabbits, suggesting that the target cells for Vn 17 may be cells related to ependyma. Malignant transformation of the cells would be initiated in the early stages after BK virus inoculation into the brain of newborn hamsters.

  11. Intermediate-dose cidofovir without probenecid in the treatment of BK virus allograft nephropathy.

    Science.gov (United States)

    Araya, Carlos E; Lew, Judy F; Fennell, Robert S; Neiberger, Richard E; Dharnidharka, Vikas R

    2006-02-01

    BK virus allograft nephropathy (BKVAN) is a rising complication in kidney transplant recipients. Reducing immunosuppression has been the initial form of therapy in most cases, but is not always associated with improvement in graft function. Anti-viral therapy with low-dose cidofovir (0.25-0.42 mg/kg/dose) has been used successfully in some patients, but dose-related nephrotoxicity has limited its use. We present our experience with 3 kidney transplant recipients diagnosed with BKVAN who received intermediate-dose cidofovir (0.75-1.0 mg/kg/dose) without probenecid, and without concomitant nephrotoxicity. Three female patients, ages 8, 19 and 20 yr, presented with elevated serum creatinine (SCr) values, BK virus stain positive on renal biopsy and high plasma BK viral loads. As a result of viral loads being >2 million copies/ml in two patients and a lack of response to reduction in immunosuppression in the third, we initiated therapy with low-dose cidofovir. Because of persistent positive BK stain and positive plasma viral load, we then administered intermediate-dose cidofovir, without probenecid, for several subsequent doses (seven to 15 infusions till date). All patients tolerated the intermediate-dose cidofovir with no significant rise in SCr during the course of the infusions. The most recent SCr values in all three patients were improved from those at the initial diagnosis of BKVAN. All three patients showed a marked drop in BK viral loads when on intermediate-dose cidofovir, with complete clearing of viremia in two patients. In our experience, intermediate-dose cidofovir without probenecid, used judiciously, is not associated with additional nephrotoxicity and may provide an additional alternative for treatment. PMID:16499584

  12. Restriction of Human Polyomavirus BK Virus DNA Replication in Murine Cells and Extracts

    OpenAIRE

    Mahon, C.; Liang, B.; Tikhanovich, I.; et al

    2009-01-01

    BK virus (BKV) causes persistent and asymptomatic infections in most humans and is the etiologic agent of polyomavirus-associated nephropathy (PVAN) and other pathologies. Unfortunately, there are no animal models with which to study activation of BKV replication in the human kidney and the accompanying PVAN. Here we report studies of the restriction of BKV replication in murine cells and extracts and the cause(s) of this restriction. Upon infection of murine cells, BKV expressed large T anti...

  13. Rapid detection and identification of JC virus and BK virus in human urine by using immunofluorescence microscopy.

    OpenAIRE

    Hogan, T. F.; Padgett, B L; Walker, D. L.; Borden, E C; McBain, J A

    1980-01-01

    An indirect immunofluorescence method was developed and used to detect urinary excretion of abnormal transitional cells infected with JC virus (JCV) or BK virus (BKV). This method was compared with urinary cytology, electron microscopy, viral culture, and viral serology in groups of immunosuppressed renal transplant recipients and normal controls. The indirect immunofluorescence method detected and identified JCV excretion in four persons, BKV excretion in one person, and both JCV and BKV exc...

  14. BK virus has tropism for human salivary gland cells in vitro: Implications for transmission

    International Nuclear Information System (INIS)

    Background: In this study, it was determined that BKV is shed in saliva and an in vitro model system was developed whereby BKV can productively infect both submandibular (HSG) and parotid (HSY) salivary gland cell lines. Results: BKV was detected in oral fluids using quantitative real-time PCR (QRTPCR). BKV infection was determined using quantitative RT-PCR, immunofluorescence and immunoblotting assays. The infectivity of BKV was inhibited by pre-incubation of the virus with gangliosides that saturated the major capsid protein, VP1, halting receptor mediated BKV entry into salivary gland cells. Examination of infected cultures by transmission electron microscopy revealed 45-50 nm BK virions clearly visible within the cells. Subsequent to infection, encapsidated BK virus was detected in the supernatant. Conclusion: We thus demonstrated that BKV was detected in oral fluids and that BK infection and replication occur in vitro in salivary gland cells. These data collectively suggest the potential for BKV oral route of transmission and oral pathogenesis.

  15. Risk Factors for the Development of BK Virus Nephropathy in Renal Transplant Recipients.

    Science.gov (United States)

    Pai, D; Mann, D M; Malik, A; Hoover, D R; Fyfe, B; Mann, R A

    2015-10-01

    The BK polyoma virus has, in recent years, become a significant cause of renal allograft dysfunction and failure. Among 260 adult kidney transplant recipients, those with biopsy-proven BK virus nephropathy (BKVN) were compared with those without BKVN with regard to gender, age, race, rejection episodes, time on dialysis, number of organs transplanted, HLA match, live donor versus deceased donor, cold ischemia time, delayed graft function, cytomegalovirus (CMV) serostatus of donor and recipient, induction therapy, and maintenance immunosuppression. Episodes of rejection (35.7% of patients with BKVN vs 8.5% of patients without BKVN; P = .01), transplantation of >1 organ (35.7% of patients with BKVN vs 9.0% of patients without BKVN; P = .01), positive CMV serology in both donor and recipient (71.4% of patients with BKVN vs 41.1% of patients without BKVN; P = .03), and a greater cumulative dose of daclizumab use at the time of induction (2.24 ± 0.05 mg/kg in patients with BKVN vs 2.03 ± 0.14 mg/kg in patients without BKVN; P = .04) were statistically significant risk factors for the development of BKVN. Those who developed BKVN received a higher mean cumulative dose of rabbit antithymoglobulin for induction therapy, but that difference failed to achieve statistical significance (P = .07). PMID:26518952

  16. No evidence for infection of UK prostate cancer patients with XMRV, BK virus, Trichomonas vaginalis or human papilloma viruses.

    Directory of Open Access Journals (Sweden)

    Harriet C T Groom

    Full Text Available The prevalence of specific infections in UK prostate cancer patients was investigated. Serum from 84 patients and 62 controls was tested for neutralisation of xenotropic murine leukaemia virus-related virus (XMRV Envelope. No reactivity was found in the patient samples. In addition, a further 100 prostate DNA samples were tested for XMRV, BK virus, Trichomonas vaginalis and human papilloma viruses by nucleic acid detection techniques. Despite demonstrating DNA integrity and assay sensitivity, we failed to detect the presence of any of these agents in DNA samples, bar one sample that was weakly positive for HPV16. Therefore we conclude that these infections are absent in this typical cohort of men with prostate cancer.

  17. The impact of surveillance and rapid reduction in immunosuppression to control BK virus-related graft injury in kidney transplantation.

    Science.gov (United States)

    Elfadawy, Nissreen; Flechner, Stuart M; Liu, Xiaobo; Schold, Jesse; Tian, Devin; Srinivas, Titte R; Poggio, Emilio; Fatica, Richard; Avery, Robin; Mossad, Sherif B

    2013-08-01

    We prospectively screened 609 consecutive kidney (538) and kidney-pancreas (71) transplant recipients for BK viremia over a 4-year interval using polymerase chain reaction viral load detection and protocol kidney biopsies. We found that BK viremia is common at our center: total cases 26.7%, cases during first year 21.3% (mean 4 months), and recipients with ≥ 10 000 copies/ml 12.3%. We found few predictive clinical or demographic risk factors for any BK viremia or viral loads ≥ 10,000 copies/ml, other than prior treatment of biopsy confirmed acute rejection and/or higher immunosuppressive blood levels of tacrolimus (P = 0.001) or mycophenolate mofetil (P = 0.007). Viral loads at diagnosis (185 000 copies/ml at diagnosis were predictive of BK virus-associated nephropathy (BKVAN; OR: 113.25, 95% CI: 17.22-744.6, P < 0.001). Surveillance for BK viremia and rapid reduction of immunosuppression limited the incidence of BKVAN to 1.3%. The addition of leflunomide or ciprofloxacin to immunosuppressive dose reduction did not result in greater rates of viral clearance. These data support the role of early surveillance for BK viremia to limit the impact on transplant outcome, although the most effective schedule for screening awaits further investigation. PMID:23763289

  18. Successful hyperbaric oxygen therapy for refractory BK virus-associated hemorrhagic cystitis after cord blood transplantation.

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    Hosokawa, K; Yamazaki, H; Nakamura, T; Yoroidaka, T; Imi, T; Shima, Y; Ohata, K; Takamatsu, H; Kotani, T; Kondo, Y; Takami, A; Nakao, S

    2014-10-01

    BK virus-associated hemorrhagic cystitis (BKV-HC) is a common and major cause of morbidity in recipients of allogeneic hematopoietic stem cell transplantation. A 32-year-old woman developed severe BKV-HC on day 24 after cord blood transplantation (CBT). Despite supportive therapies - such as hyperhydration, forced diuresis, and urinary catheterization - macroscopic hematuria and bladder irritation persisted for over a month. Hyperbaric oxygen (HBO) therapy at 2.1 atmospheres for 90 min per day was started on day 64 after CBT. Macroscopic hematuria resolved within a week, and microscopic hematuria was no longer detectable within 2 weeks. Hematuria did not recur after 11 sessions of HBO therapy, and no significant side effects were observed during or after treatment. HBO therapy could thus be useful in controlling refractory BKV-HC after CBT. PMID:25040402

  19. No detection of BK virus, JC virus, KI, WU and Merkel cell polyomaviruses in cerebrospinal fluid of patients with neurological complications after hematopoetic stem cell transplantation.

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    Rubin, J; Giraud, G; Priftakis, P; Wide, K; Gustafsson, B; Ramqvist, T; Dalianis, T

    2011-10-01

    Neurological complications, often due to viral reactivation, after allogeneic hematopoetic stem cell transplantation (HSCT) are associated with increased mortality. Here, cerebrospinal fluid from 20 HSCT patients with neurological symptoms were analyzed and found to be negative by PCR for BK virus, JC virus, KI, WU and Merkel cell polyomavirus DNA. PMID:21965766

  20. A single-center epidemiological study of BK virus infection and analysis of risk factors in patients with renal transplantation

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    Ji-gang LI

    2014-10-01

    Full Text Available Objective To investigate the epidemiological characteristics of BK virus (BKV infection in living renal transplantation patients, and analyze the risk factors of BKV infection and BKV nephropathy (BKVN. Methods The BKV DNA load in urine and blood samples of 43 renal transplant recipients, who had received renal transplantation in 309 Hospital from Feb. 2012 to Feb. 2013, was determined at preoperative period and 0.5, 1, 3, 6, 9, 12 and 15 months after transplantation. Meanwhile, the biopsy of grafted kidney was performed in those patients with continuously elevated serum creatinine and those with higher BKV DNA load. Patients were divided into 3 groups as follows according to the test results: BK viruria group, BK viremia group and pathologically diagnosed BKVN group. Data of each group were then recorded, including gender, age, postoperative diabetes (PTDM, acute rejection (AR, delayed recovery of graft function (DGF, postoperative pulmonary infection, preoperative immune induction therapy, postoperative immunosuppressive regimen, and other information. The risk factors for postoperative BKV infection and BKVN were analyzed. Results After an average of 15-month follow-up, it was found that the incidence of BKV viruria was 46.5%, that of BKV viremia was 14.0%, and that of BKVN was 2.3%. Sixth month after transplantation was found to be the peak time of viruria and viremia. FK506 was significantly associated with viremia in living donor renal transplantation. The immunosuppressive regimen was the immune related independent risk factor for BK viremia developing BKVN after living renal transplantation. Conclusion The incidence of BK viremia and BKVN is lower in living donor renal transplantation than in cadaver renal transplantation, but that of viruria is similar in both groups. Immunosuppressive scheme based on FK506 is an immune related independent risk factor leading to BK viremia proceeding to BKVN in living donor kidney

  1. Urological management (medical and surgical) of BK-virus associated haemorrhagic cystitis in children following haematopoietic stem cell transplantation

    OpenAIRE

    Nikhil Vasdev; Angela Davidson; Christian Harkensee; Mary Slatter; Andrew Gennery; Ian Willetts; Andrew Thorpe

    2013-01-01

    Aim: Haemorrhagic cystitis (HC) is uncommon and in its severe form potentially life threatening complication of Haematopoietic stem cell transplantation (HSCT) in children. We present our single centre experience in the urological management of this clinically challenging condition. Patients and Methods: Fourteen patients were diagnosed with BK-Virus HC in our centre. The mean age at diagnosis was 8.8 years (range, 3.2-18.4 years). The mean number of days post-BMT until onset of HC was 20.8 (...

  2. Molecular characterization of BK virus in patients infected with human immunodeficiency virus.

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    Karalic, Danijela; Lazarevic, Ivana; Banko, Ana; Cupic, Maja; Jevtovic, Djordje; Jovanovic, Tanja

    2016-04-01

    Immunosuppression seems to be the most important cause of BKPyV reactivation. Recently, a spectrum of diseases associated with BKPyV infection has been reported in HIV-infected patients. BKPyV isolates can be classified into four subtypes based on nucleotide polymorphisms within VP1 coding region. Mutations within the BC loop of the VP1 may be associated with an increase in the viral pathogenicity. The aims of this study were to determine prevalence and distribution of BKPyV subtypes, sequence variation and mutations within VP1 among HIV-infected patients and healthy donors. Urine samples from 114 HIV-infected patients and 120 healthy donors were collected. PCR followed by sequence analysis was carried out using primers specific for VP1 and NCRR of the virus genome. The predominant BKPyV subtype was I, followed by IV. In isolates from HIV-infected patients, the majority of non-synonymous alterations were located within the BC loop. BKV sequences from healthy donors showed non-synonymous alterations outside of the receptor loops in the β-sheets. The higher frequency of mutations in the BC loop of VP1 protein was detected among HIV-infected patients. The most frequent mutation was E82D. All HIV-infected patients who harbored mutations had CD4(+) cell counts less than 200 cell/mm(3). It seems that immunosuppression is a very important factor for BKPyV reactivation that can increase viral replication rate and leads to higher frequency of mutations in the BC loop of the VP1. These mutations may change receptor specificity, and further studies are needed to determine the effect of these mutations on the biological properties of the BKPyV. PMID:26498471

  3. An Association between BK Virus Replication in Bone Marrow and Cytopenia in Kidney-Transplant Recipients

    OpenAIRE

    Emilie Pambrun; Catherine Mengelle; Geneviève Fillola; Patrick Laharrague; Laure Esposito; Isabelle Cardeau-Desangles; Arnaud Del Bello; Jacques Izopet; Lionel Rostaing; Nassim Kamar

    2014-01-01

    The human polyomavirus BK (BKV) is associated with severe complications, such as ureteric stenosis and polyomavirus-associated nephropathy (PVAN), which often occur in kidney-transplant patients. However, it is unknown if BKV can replicate within bone marrow. The aim of this study was to search for BKV replication within the bone marrow of kidney-transplant patients presenting with a hematological disorder. Seventy-two kidney-transplant patients underwent bone-marrow aspiration for cytopenia....

  4. BK virus encephalopathy and sclerosing vasculopathy in a patient with hypohidrotic ectodermal dysplasia and immunodeficiency

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    Darbinyan, Armine; Major, Eugene O.; Morgello, Susan; Holland, Steven; Ryschkewitsch, Caroline; Monaco, Maria Chiara; Naidich, Thomas P.; Bederson, Joshua; Malaczynska, Joanna; Ye, Fei; Gordon, Ronald; Cunningham-Rundles, Charlotte; Fowkes, Mary; Tsankova, Nadejda M.

    2016-01-01

    Human BK polyomavirus (BKV) is reactivated under conditions of immunosuppression leading most commonly to nephropathy or cystitis; its tropism for the brain is rare and poorly understood. We present a unique case of BKV-associated encephalopathy in a man with hypohidrotic ectodermal dysplasia and immunodeficiency (HED-ID) due to IKK-gamma (NEMO) mutation, who developed progressive neurological symptoms. Brain biopsy demonstrated polyomavirus infection of gray and white matter, with predominan...

  5. 肾移植术后BK病毒相关性肾病的研究现状%Study on BK virus-associated nephropathy after renal transplantation

    Institute of Scientific and Technical Information of China (English)

    肖荆; 田野

    2008-01-01

    BACKGROUND: BK viral infection after renal transplantation influences the prognosis of BK virus-associated nephropathy in renal transplant recipients. The disease has been widely studied in foreign countries.OBJECTIVE: This study was designed to sum up the diagnosis and treatment of BK virus-associated nephropathy after renal transplantation.RETRIVAL STRATEGY: Using the terms "renal transplantation; BK virus" in the English language, manuscripts responsible for BK virus-associated nephropathy after renal transplantation that were published from January 2000 to January 2007 were retrieved from the PubMed database. A total of 206 manuscripts were obtained and primarily screened. Inclusion criteria: studies addressing BK virus-associated nephropathy after renal transplantation. Exclusion criteria: repetitive studies.LITERATURE EVALUATION: The included manuscripts were primarily from PubMed database. Manuscripts were primarily original and review studies.DATA SYNTHESIS: BK virus can be found in the urine of 3%-40% of adult renal transplant recipients. BK virus reactivation rate is very high, but the histological manifestations of BK virus associated nephropathy are found only in a small number of renal transplant recipients. The prognosis of BK virus associated nephropathy is very poor. BK virus associated nephropathy develops into renal failure, leading to transplant loss, in 30%-50% patients. BK virus-caused renal transplant disease must be diagnosed according to histological manifestations. Viral infection should be primarily confirmed, but serological measurements have no predominant effects. Electron microscopy should be involved in the assessment of renal graft biopsy, especially when renal failure factors are unknown, as through the use of electron microscope, viral particles in the nucleus, cytoplasm and outside of the cells could be detectable. Viral antigen in the urine sample of patients with BK viruria can be detected by nucleic acid hybridization method

  6. Association between a High BK Virus Load in Urine Samples of Patients with Graft-Versus-Host Disease and Development of Hemorrhagic Cystitis after Hematopoietic Stem Cell Transplantation

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    Bogdanovic, G; Priftakis, P.; Giraud, G.; Kuzniar, M.; Ferraldeschi, R; Kokhaei, P.; Mellstedt, H.; Remberger, M; Ljungman, P.; Winiarski, J.; Dalianis, T

    2004-01-01

    BK virus (BKV) load in urine alone or in combination with acute graft-versus-host disease (GVHD) was correlated to development of hemorrhagic cystitis (HC). BKV load in combination with acute GVHD discriminated the best, while BKV and viral load alone, but not GVHD, still showed predictive ability for HC.

  7. Evaluation of the Genetic Variation of Non Coding Control Region of BK Virus Using Nested-PCR Sequencing Method in Renal Graft Patients

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    A Emami

    2015-05-01

    Full Text Available Background & aim: Polyomaviruses (BK is a comprehensive infection with more than of 80% prevalence in the world. One of the most important reasons of BK virus nephropathy is in the renal transplant recipients and rejection of transplanted tissue between them. Non Coding region of this virus play a regulatory role in replication and amplification of the virus. The aim of this study was to evaluate the genetic patterns of this area in renal graft at Namazi Transplantation Center, Shiraz, Iran. Methods: In the present experimental study, 380 renal allograft serums were collected. DNAs of 129 eligible samples were extracted and evaluated using a virus genome. The presence of the virus was determined by qualitative and sequencing. Of these, 129 samples were tested for the presence of virus according to the condition study, using quantitative, qualitative genomic amplification and sequencing. Results: The study showed symptoms of nephropathy, 76 (58.9% of them were males and 46 (35.7% were females with the mean age 38.0±.089 years of age. In general, 46 patients (35.7% percent were positive for BK Polyomaviruses. After comparing the genomic sequence with applications of molecular they were categorized in three groups and then recorded in gene bank. Conclusion: About 35% of renal transplant recipients with high creatinine levels were positive for the presence of BK virus. Non-coding region of respondents in the sample survey revealed that among patients with the most common genotypes were rearranged the entire transplant patients were observed at this tranplant center. Examination of these sequences indicated that this rearrangments had a specific pattern, different from the standard strain of archaea type.

  8. Urological management (medical and surgical of BK-virus associated haemorrhagic cystitis in children following haematopoietic stem cell transplantation

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    Nikhil Vasdev

    2013-10-01

    Full Text Available Aim: Haemorrhagic cystitis (HC is uncommon and in its severe form potentially life threatening complication of Haematopoietic stem cell transplantation (HSCT in children. We present our single centre experience in the urological management of this clinically challenging condition. Patients and Methods: Fourteen patients were diagnosed with BK-Virus HC in our centre. The mean age at diagnosis was 8.8 years (range, 3.2-18.4 years. The mean number of days post-BMT until onset of HC was 20.8 (range, 1 – 51. While all patients tested urine positive for BKV at the clinical onset of HC, only four patients had viral quantification, with viral loads ranging from 97,000 to >1 billion/ml. 8 patients had clinical HC. Ten patients experienced acute GVHD (grade I: 6 patients, grade II: 3 patients, grade 4: 1 patient.Results: Four patients received medical management for their HC. Treatments included hyperhydration, MESNA, blood and platelet transfusion, premarin and oxybutynin (Table 6.  Two patients received both medical and surgical management which included cystoscopy with clot evacuation, bladder irrigation and supra-pubic catheter insertion. One patient received exclusive surgical management. Seven patients were treated conservatively. Conclusion: There is limited available evidence for other potential therapeutic strategies highlighting the need for more research into the pathophysiology of HSCT-associated HC. Commonly used interventions with possible clinical benefit (e.g. cidofovir, ciprofloxacin still require to be evaluated in multi-centre, high-quality studies. Potential future preventative and therapeutic options, such as modulation of conditioning, immunosuppression and engraftment, new antiviral and anti-inflammatory and less nephrotoxic agents need to be assessed.---------------------------Cite this article as:Vasdev N, Davidson A, Harkensee C, Slatter M, Gennery A, Willetts I, Thorpe A.Urological management (medical and surgical of BK-virus

  9. Transformation of primary human embryonic kidney cells to anchorage independence by a combination of BK virus DNA and the Harvey-ras oncogene

    International Nuclear Information System (INIS)

    Primary human embryonic kidney (HEK) cells were transformed by a focus assay with BK virus (BKV) DNA molecularly cloned at its unique EcoRI site. Both viral DNA sequences and viral tumor antigens were present and expressed in all the foci that the authors examined. However, cells isolated from foci were incapable of growth in soft agar. They then examined the transformation of HEK cells after their transfection with a combination of BKV DNA and either the normal or the activated form of the human Ha-ras oncogene (EJ c-Ha-ras-1). Only the cells transfected with a combination of BKV DNA and the activated form of Ha-ras DNAs were present in the transformed colonies. BKV tumor antigens and the Ha-ras p21 protein were also expressed

  10. New insights on the association between the prostate cancer and the small DNA tumour virus, BK polyomavirus.

    Science.gov (United States)

    Tognon, Mauro; Provenzano, Maurizio

    2015-01-01

    In recent years the scientific literature in the field of the prostate carcinoma (PCa) pointed out on the genetic heterogeneity and mutations occurring in this tumour, while little attention was given to the causes of PCa onset, in particular infectious agents. In this brief commentary, we wish to point out recent advancements done on the role of the human polyomavirus BK (BKPyV) in the development of PCa by harnessing both humoral and cellular immune responses. Altogether, these new insights suggest that BKPyV is involved in the transforming activity during the multistep process of PCa development. Although these findings do not provide evidence for a causal relationship between BKPyV and PCa development, additional investigations with novel techniques will help to make it a concrete event. PMID:26699530

  11. Polyomavirus BK infection in blood and marrow transplant recipients

    OpenAIRE

    Dropulic, LK; Jones, RJ

    2007-01-01

    The association of BK virus infection with hemorrhagic cystitis in blood and marrow transplant (BMT) recipients was first demonstrated two decades ago. During this time, therapeutic interventions focused on supportive measures such as hyperhydration, continuous bladder irrigation and topical administration of agents that alter the mucosal surface of the bladder wall. In recent years, PCR amplification of viral DNA in the urine and plasma has solidified the association of BK virus infection wi...

  12. Exposing the Molecular Machinery of BK Polyomavirus.

    Science.gov (United States)

    Buck, Christopher B

    2016-04-01

    BK polyomavirus (BKV) is an opportunistic pathogen that poses a serious threat to organ transplant recipients. In this issue of Structure, Hurdiss and colleagues' (Hurdiss et al., 2016) beautiful new high-resolution cryo-EM reconstruction of BKV provides a structural roadmap for the ongoing development of therapeutic antibodies and vaccines targeting this potentially deadly virus. The study also serves as a platform for exploring the basic biology of virion assembly and infectious entry. PMID:27050683

  13. Reactivation of BK polyomavirus in patients with multiple sclerosis receiving natalizumab therapy.

    LENUS (Irish Health Repository)

    Lonergan, Roisin M

    2012-02-01

    Natalizumab therapy in multiple sclerosis has been associated with JC polyomavirus-induced progressive multifocal leucoencephalopathy. We hypothesized that natalizumab may also lead to reactivation of BK, a related human polyomavirus capable of causing morbidity in immunosuppressed groups. Patients with relapsing remitting multiple sclerosis treated with natalizumab were prospectively monitored for reactivation of BK virus in blood and urine samples, and for evidence of associated renal dysfunction. In this cohort, JC and BK DNA in blood and urine; cytomegalovirus (CMV) DNA in blood and urine; CD4 and CD8 T-lymphocyte counts and ratios in peripheral blood; and renal function were monitored at regular intervals. BK subtyping and noncoding control region sequencing was performed on samples demonstrating reactivation. Prior to commencement of natalizumab therapy, 3 of 36 patients with multiple sclerosis (8.3%) had BK viruria and BK reactivation occurred in 12 of 54 patients (22.2%). BK viruria was transient in 7, continuous in 2 patients, and persistent viruria was associated with transient viremia. Concomitant JC and CMV viral loads were undetectable. CD4:CD8 ratios fluctuated, but absolute CD4 counts did not fall below normal limits. In four of seven patients with BK virus reactivation, transient reductions in CD4 counts were observed at onset of BK viruria: these resolved in three of four patients on resuppression of BK replication. No renal dysfunction was observed in the cohort. BK virus reactivation can occur during natalizumab therapy; however, the significance in the absence of renal dysfunction is unclear. We propose regular monitoring for BK reactivation or at least for evidence of renal dysfunction in patients receiving natalizumab.

  14. Impact of preemptive reduction of immunosuppression with serial monitoring for BK virus replication in renal transplant recipients undergoing short-term evaluation.

    Science.gov (United States)

    De Paolis, P; Gervasio, E; Tedesco, M; Favarò, A; Iappelli, M; Abbate, I; Capobianchi, M; Di Giulio, S

    2009-05-01

    The aim of this preliminary, prospective, longitudinal study was to evaluate the effects on graft function and viral loads of modulation of immunosuppressive therapy based upon serial noninvasive monitoring of urine and serum viral loads with real-time polymerase chain reaction among unselected renal transplant recipients. Thirty-nine renal transplant recipients with follow-up times of 7.8 +/- 4.3 months were monitored monthly with urine and serum samples to measure BK viral load. Interventions such as gradual reductions of mycophenolate mofetil and/or tacrolimus were performed when repeated urine and serum viral loads were >10(5) and >10(3) copies/mL, respectively. Among 271 samples, the patients were divided into 6 groups: negative urine (group = 1; n = 10) and negative serum (group 2; n = 25) versus BK viral loads that were intermittent (urine: group 3; n = 24 and serum: group 4; n = 11) versus persistent (urine: group 5; n = 5 and serum: group 6; n = 3). In groups 3-4 we observed the higher viral loads in the urine than in the serum (10(3): 21; 10(4): 1; 10(5): 1; 10(6): 1 vs 10(2): 8; 10(3): 2; 10(4): 1). The timing of resolution of viremia was more rapid than viruria. In groups 5-6 we observed the greatest viral load and greater number in urine. The overall incidences of viruria and viremia were 74.3% and 35.9%, respectively. The overall rates of clearance of viruria were 26/29 recipients (89%) and viremia, 11/14 recipients (78%). Only 10 patients (25.6%) needed extensive reduction of immunosuppression. No modifications of serum creatinine levels and no rejection episodes were observed. In conclusion this preliminary analysis suggested that serial, noninvasive monitoring of viral load allows gradual premptive reduction of immunosuppression with consequent strong reduction in viral load. PMID:19460518

  15. Series BK contactless DC motors

    Energy Technology Data Exchange (ETDEWEB)

    Buss, V.A.; Vevyurko, I.A.; Ivanov, G.V.; Kuzmin, V.N.; Mikhaylov, E.M.; Stoma, A.S.

    1985-05-01

    Implementation of principles described in a previous work has allowed development and introduction to series production of a motor series including 36 standard types and sizes. The series is designed to operate at a nominal voltage of 27 V and includes two main versions: the BK-1 for fans and BK-2 for pumps. The BK-2 motor differs from the BK-1 in that it has a thin sealed sleeve of high impedance nonmagnetic metal separating the rotor and stator cavities, allowing the rotor of the BK-2 to operate in the fluids or other media being pumped. Characteristics of the motors are presented. The BK-1316 has an operating life of about 50,000 hours at nominal speed of 6000 rpm. The experience of series production of the BK motors has shown the need for further improvement of the design and technology in order to decrease the number of metal cutting, winding and assembly operations required. The use of plastic structures is suggested to this end.

  16. BK channel modulators: a comprehensive overview

    DEFF Research Database (Denmark)

    Nardi, Antonio; Olesen, Søren-Peter

    2008-01-01

    the multitude of chemical entities claimed to be BK-modulating agents. Such chemical entities are, herein, classified by both origin and chemical structure in 1) Endogenous BK channel modulators and structural analogues 2) Naturally-occurring BK channel inhibitors and blockers 3) Synthetic BK channel...... inhibitors and blockers 4) Marketed and/or investigational drugs with BK-modulating side properties and structural analogues 5) Naturally-occurring BK channel openers and structural analogues 6) Synthetic BK channel openers. This review is intended to provide readers with current opinion on the BK channel as...... a drug target, the chemical structures of BK channel modulators, the structural and chemical features involved in the BK channel modulating activity and, where and when possible, with highlights of structure-activity relationships....

  17. EC decay of 244Bk

    Science.gov (United States)

    Sodaye, Suparna; Tripathi, R.; Sudarshan, K.; Sharma, S. K.; Pujari, P. K.; Palit, R.; Mukhopadhyay, S.

    2014-12-01

    Berkelium isotopes have been produced in 11B-induced reaction on 238U. The EC decay of 244Bk → 244Cm has been studied by carrying out the single and coincidence measurements of the γ-rays emitted during the de-excitation of the 244Cm levels. Radiochemical separations have been carried out to minimize the contribution from the fission products and target. The new half-life of 244Bk is obtained as 5.02 ± 0.03 h, which is close to the theoretically calculated value. The relative intensities of the decay γ-rays have been re-evaluated. Based on the coincidence measurements, a tentative partial level scheme for 244Bk → 244Cm decay has been proposed.

  18. EC decay of 244Bk

    International Nuclear Information System (INIS)

    Berkelium isotopes have been produced in 11B-induced reaction on 238U. The EC decay of 244Bk → 244Cm has been studied by carrying out the single and coincidence measurements of the γ-rays emitted during the de-excitation of the 244Cm levels. Radiochemical separations have been carried out to minimize the contribution from the fission products and target. The new half-life of 244Bk is obtained as 5.02 ± 0.03 h, which is close to the theoretically calculated value. The relative intensities of the decay γ-rays have been re-evaluated. Based on the coincidence measurements, a tentative partial level scheme for 244Bk → 244Cm decay has been proposed. (paper)

  19. Biophysics of BK Channel Gating.

    Science.gov (United States)

    Pantazis, A; Olcese, R

    2016-01-01

    BK channels are universal regulators of cell excitability, given their exceptional unitary conductance selective for K(+), joint activation mechanism by membrane depolarization and intracellular [Ca(2+)] elevation, and broad expression pattern. In this chapter, we discuss the structural basis and operational principles of their activation, or gating, by membrane potential and calcium. We also discuss how the two activation mechanisms interact to culminate in channel opening. As members of the voltage-gated potassium channel superfamily, BK channels are discussed in the context of archetypal family members, in terms of similarities that help us understand their function, but also seminal structural and biophysical differences that confer unique functional properties. PMID:27238260

  20. BK polyomavirus association with colorectal cancer development.

    Science.gov (United States)

    Khabaz, M N; Nedjadi, T; Gari, M A; Al-Maghrabi, J A; Atta, H M; Basuni, A A; Elderwi, D A

    2016-01-01

    The development of human neoplasms can be provoked by exposure to one of several viruses. Burkitt lymphoma, cervical carcinoma, and hepatocellular carcinoma are associated with Epstein-Barr, human papilloma, and hepatitis B virus infections, respectively. Over the past three decades, many studies have attempted to establish an association between colorectal cancer and viruses, with debatable results. The aim of the present research was to assess the presence of BK polyomavirus (BKV) DNA and protein in colorectal cancer samples from patients in the Western Province of Saudi Arabia. DNA extracted from archival samples of colorectal cancer tissues was analyzed for BKV sequences using polymerase chain reaction (PCR)-based techniques. In addition, expression of a BKV protein was assessed using immunohistochemical staining. None of the tumor and control samples examined tested positive for BKV DNA in PCR assays. Furthermore, immunohistochemical staining failed to detect viral proteins in both cancer and control specimens. These results may indicate that BKV is not associated with the development of colorectal adenocarcinoma in patients in the Western Province of Saudi Arabia. PMID:27173319

  1. New berkelium isotope: 242Bk

    International Nuclear Information System (INIS)

    A new isotope of berkelium, 242Bk, was produced with a cross section of approx. 10 μb in reactions of boron on uranium and nitrogen on thorium. It decays by electron capture with a half-life of 7 +- 1.3 minutes. The branching ratio for this isotope for alpha decay is less than 1% and that for spontaneous fission is less than 0.03%. 2 figures, 2 tables

  2. Update on BK with Wilson fermions

    International Nuclear Information System (INIS)

    The K-anti K mixing matrix element is a hadronic matrix element that is of crucial importance to electroweak phenomenology. For convenience, the authors introduce the so called bag parameter, BK. It has been known for a long time that BK is amenable to lattice Monte-Carlo methods. Indeed, recently Sharpe and collaborators, using staggered formulation for fermions have made remarkable progress in calculating BK and have reported a result with an impressive accuracy. In this work the authors will present their results for BK using the Wilson formulation for fermions

  3. B_K from improved staggered quarks

    OpenAIRE

    Gamiz, E.; Collins, S.; Davies, C. T. H.; Shigemitsu, J.; Wingate, M

    2004-01-01

    We compare calculations of B_K with improved staggered quarks (HYP, Asqtad) and demonstrate the improved scaling behaviour that this gives rise to over previous calculations with unimproved staggered quarks. This enables us to perform the calculation of B_K on the MILC dynamical configurations (n_f=2+1), for which we give preliminary results.

  4. BK channel activators and their therapeutic perspectives

    DEFF Research Database (Denmark)

    Bentzen, Bo Hjorth; Olesen, Søren-Peter; Rønn, Lars C B;

    2014-01-01

    The large conductance calcium- and voltage-activated K(+) channel (KCa1.1, BK, MaxiK) is ubiquitously expressed in the body, and holds the ability to integrate changes in intracellular calcium and membrane potential. This makes the BK channel an important negative feedback system linking increase...... years. After a short introduction to the structure, function and regulation of BK channels, we review the small organic molecules activating BK channels and how these tool compounds have helped delineate the roles of BK channels in health and disease.......The large conductance calcium- and voltage-activated K(+) channel (KCa1.1, BK, MaxiK) is ubiquitously expressed in the body, and holds the ability to integrate changes in intracellular calcium and membrane potential. This makes the BK channel an important negative feedback system linking increases...... in intracellular calcium to outward hyperpolarizing potassium currents. Consequently, the channel has many important physiological roles including regulation of smooth muscle tone, neurotransmitter release and neuronal excitability. Additionally, cardioprotective roles have been revealed in recent...

  5. The H2BK123Rgument

    OpenAIRE

    Latham, John A.; Dent, Sharon Y. R.

    2009-01-01

    The discovery of trans-regulation of histone H3K4 methylation by ubiquitination of histone H2BK123 generated much excitement in the field of chromatin biology. Recently, the veracity of this example of cross talk between histone modifications in yeast was challenged (Foster and Downs, 2009. J. Cell Biol. doi:10.1083/jcb.200812088) but ultimately reconfirmed in a study in this issue (Nakanishi et al., 2009. J. Cell Biol. doi:10.1083/jcb.200906005).

  6. An Echo of Supernova 2008bk

    CERN Document Server

    Van Dyk, Schuyler D

    2013-01-01

    I have discovered a prominent light echo around the low-luminosity Type II-Plateau Supernova (SN) 2008bk in NGC 7793, seen in archival images obtained with the Wide Field Channel of the Advanced Camera for Surveys on-board the Hubble Space Telescope (HST). The echo is a partial ring, brighter to the north and east than to the south and west. The analysis of the echo I present suggests that it is due to the SN light pulse scattered by a sheet, or sheets, of dust located ~15 pc from the SN. The composition of the dust is assumed to be of standard Galactic diffuse interstellar grains. The visual extinction of the dust responsible for the echo is A_V ~ 0.05 mag, in addition to the extinction due to the Galactic foreground toward the host galaxy. That the SN experienced much less overall extinction implies that it is seen through a less dense portion of the interstellar medium in its environment. The late-time HST photometry of SN 2008bk also clearly demonstrates that the progenitor star has vanished.

  7. Developmental expression of BK channels in chick cochlear hair cells

    Directory of Open Access Journals (Sweden)

    Tong Mingjie

    2009-12-01

    Full Text Available Abstract Background Cochlear hair cells are high-frequency sensory receptors. At the onset of hearing, hair cells acquire fast, calcium-activated potassium (BK currents, turning immature spiking cells into functional receptors. In non-mammalian vertebrates, the number and kinetics of BK channels are varied systematically along the frequency-axis of the cochlea giving rise to an intrinsic electrical tuning mechanism. The processes that control the appearance and heterogeneity of hair cell BK currents remain unclear. Results Quantitative PCR results showed a non-monotonic increase in BK α subunit expression throughout embryonic development of the chick auditory organ (i.e. basilar papilla. Expression peaked near embryonic day (E 19 with six times the transcript level of E11 sensory epithelia. The steady increase in gene expression from E11 to E19 could not explain the sudden acquisition of currents at E18-19, implicating post-transcriptional mechanisms. Protein expression also preceded function but progressed in a sequence from diffuse cytoplasmic staining at early ages to punctate membrane-bound clusters at E18. Electrophysiology data confirmed a continued refinement of BK trafficking from E18 to E20, indicating a translocation of BK clusters from supranuclear to subnuclear domains over this critical developmental age. Conclusions Gene products encoding BK α subunits are detected up to 8 days before the acquisition of anti-BK clusters and functional BK currents. Therefore, post-transcriptional mechanisms seem to play a key role in the delayed emergence of calcium-sensitive currents. We suggest that regulation of translation and trafficking of functional α subunits, near voltage-gated calcium channels, leads to functional BK currents at the onset of hearing.

  8. Hemorrhagic Cystitis due to BK Reactivation in a Young Female Treated for Hodgkin-Disease

    Directory of Open Access Journals (Sweden)

    R. Le Calloch

    2011-01-01

    Full Text Available Hodgkin's lymphoma is a disease with a high rate of curability under classic chemo-radiotherapy regimes. Complications due to chemotherapy could include viral reactivation due to chronic lymphopenia. BK virus (BKV is a polyoma virus belonging to the Papovaviridae family with antibody seroprevalences in healthy populations varying from 60% to 80%. Initial infections are asymptomatic usually occur in early childhood, after which the viruses remain latent in the kidneys or urothelium. Reactivation of BKV occurs in individuals with severe immunosuppression during HIV infections, transplantation or, exceptionally, after classical chemotherapy. BKV incidence is approximately 0% to 5% in immunocompetent individuals. Reactivation is associated with nephropathy and haemorrhagic cystitis. Herein, we present a case of a haemorrhagic cystitis due to BKV reactivation in a patient with Hodgkin's disease treated with chemotherapy.

  9. Address Points, areas-bk, Published in 2005, Daggett County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Address Points dataset, was produced all or in part from Other information as of 2005. It is described as 'areas-bk'. Data by this publisher are often provided...

  10. BK Polyomavirus Infection and Renourinary Tumorigenesis.

    Science.gov (United States)

    Papadimitriou, J C; Randhawa, P; Rinaldo, C Hanssen; Drachenberg, C B; Alexiev, B; Hirsch, H H

    2016-02-01

    BK polyomavirus (BKPyV) infection represents a major problem in transplantation, particularly for renal recipients developing polyomavirus-associated nephropathy (PyVAN). The possibility that BKPyV may also be oncogenic is not routinely considered. Twenty high-grade renourinary tumors expressing polyomavirus large T antigen in the entirety of the neoplasm in 19 cases, including the metastases in six, have been reported in transplant recipients with a history of PyVAN or evidence of BKPyV infection. Morphological and phenotypical features consistent with inactivation of the tumor suppressors pRB and p53 were found in the bladder tumors, suggesting a carcinogenesis mechanism involving the BKPyV large tumor oncoprotein/antigen. The pathogenesis of these tumors is unclear, but given the generally long interval between transplantation and tumor development, the risk for neoplasms after BKPyV infections may well be multifactorial. Other elements potentially implicated include exposure to additional exogenous carcinogens, further viral mutations, and cell genomic instability secondary to viral integration, as occurs with the Merkel cell PyV-associated carcinoma. The still scarce but increasingly reported association between longstanding PyVAN and renourinary neoplasms requires a concerted effort from the transplant community to better understand, diagnose, and treat the putative association between the BKPyV and these neoplasms. PMID:26731714

  11. Universal features of JIMWLK and BK evolution at small x

    OpenAIRE

    Rummukainen, Kari; Weigert, Heribert

    2003-01-01

    In this paper we present the results of numerical studies of the JIMWLK and BK equations with a particular emphasis on the universal scaling properties and phase space structure involved. The results are valid for near zero impact parameter in DIS. We demonstrate IR safety due to the occurrence of a rapidity dependent saturation scale Q_s(\\tau). Within the set of initial conditions chosen both JIMWLK and BK equations show remarkable agreement. We point out the crucial importance of running co...

  12. Universal features of JIMWLK and BK evolution at small x

    International Nuclear Information System (INIS)

    In this paper we present the results of numerical studies of the JIMWLK and BK equations with a particular emphasis on the universal scaling properties and phase space structure involved. The results are valid for near zero impact parameter in DIS. We demonstrate IR safety due to the occurrence of a rapidity-dependent saturation scale Qs(τ). Within the set of initial conditions chosen, both JIMWLK and BK equations show remarkable agreement. We point out the crucial importance of running coupling corrections to obtain consistency in the UV for both equations. Explicit studies of this have been performed with BK. Despite the scale breaking induced by the running coupling we find that evolution drives correlators towards an asymptotic form with near scaling properties. We discuss asymptotic features of the evolution, such as the τ- and A-dependence of Qs away from the initial condition

  13. Universal features of JIMWLK and BK evolution at small x

    Energy Technology Data Exchange (ETDEWEB)

    Rummukainen, Kari; Weigert, Heribert E-mail: heribert.weigert@physik.uni-regensburg.de

    2004-07-12

    In this paper we present the results of numerical studies of the JIMWLK and BK equations with a particular emphasis on the universal scaling properties and phase space structure involved. The results are valid for near zero impact parameter in DIS. We demonstrate IR safety due to the occurrence of a rapidity-dependent saturation scale Q{sub s}({tau}). Within the set of initial conditions chosen, both JIMWLK and BK equations show remarkable agreement. We point out the crucial importance of running coupling corrections to obtain consistency in the UV for both equations. Explicit studies of this have been performed with BK. Despite the scale breaking induced by the running coupling we find that evolution drives correlators towards an asymptotic form with near scaling properties. We discuss asymptotic features of the evolution, such as the {tau}- and A-dependence of Q{sub s} away from the initial condition.

  14. Coronary arterial BK channel dysfunction exacerbates ischemia/reperfusion-induced myocardial injury in diabetic mice.

    Science.gov (United States)

    Lu, Tong; Jiang, Bin; Wang, Xiao-Li; Lee, Hon-Chi

    2016-09-01

    The large conductance Ca(2+)-activated K(+) (BK) channels, abundantly expressed in coronary artery smooth muscle cells (SMCs), play a pivotal role in regulating coronary circulation. A large body of evidence indicates that coronary arterial BK channel function is diminished in both type 1 and type 2 diabetes. However, the consequence of coronary BK channel dysfunction in diabetes is not clear. We hypothesized that impaired coronary BK channel function exacerbates myocardial ischemia/reperfusion (I/R) injury in streptozotocin-induced diabetic mice. Combining patch-clamp techniques and cellular biological approaches, we found that diabetes facilitated the colocalization of angiotensin II (Ang II) type 1 receptors and BK channel α-subunits (BK-α), but not BK channel β1-subunits (BK-β1), in the caveolae of coronary SMCs. This caveolar compartmentation in vascular SMCs not only enhanced Ang II-mediated inhibition of BK-α but also produced a physical disassociation between BK-α and BK-β1, leading to increased infarct size in diabetic hearts. Most importantly, genetic ablation of caveolae integrity or pharmacological activation of coronary BK channels protected the cardiac function of diabetic mice from experimental I/R injury in both in vivo and ex vivo preparations. Our results demonstrate a vascular ionic mechanism underlying the poor outcome of myocardial injury in diabetes. Hence, activation of coronary BK channels may serve as a therapeutic target for cardiovascular complications of diabetes. PMID:27574914

  15. Interacting influence of diuretics and diet on BK channel-regulated K homeostasis.

    Science.gov (United States)

    Wen, Donghai; Cornelius, Ryan J; Sansom, Steven C

    2014-04-01

    Large conductance, Ca-activated K channels (BK) are abundantly located in cells of vasculature, glomerulus, and distal nephron, where they are involved in maintaining blood volume, blood pressure, and K homeostasis. In mesangial cells and smooth muscle cells of vessels, the BK-α pore associates with BK-β1 subunits and regulates contraction in a Ca-mediated feedback manner. The BK-β1 also resides in connecting tubule cells of the nephron. BK-β1 knockout mice (β1KO) exhibit fluid retention, hypertension, and compromised K handling. The BK-α/β4 resides in acid/base transporting intercalated cells (IC) of the distal nephron, where they mediate K secretion in mammals on a high K, alkaline diet. BK-α expression in IC is increased by a high K diet via aldosterone. The BK-β4 subunit and alkaline urine are necessary for the luminal expression and function of BK-α in mouse IC. In distal nephron cells, membrane BK-α expression is inhibited by WNK4 in in vitro expression systems, indicating a role in the hyperkalemic phenotype in patients with familial hyperkalemic hypertension type 2 (FHHt2). β1KO and BK-β4 knockout mice (β4KO) are hypertensive because of exaggerated epithelial Na channels (ENaC) mediated Na retention in an effort to secrete K via only renal outer medullary K channels (ROMK). BK hypertension is resistant to thiazides and furosemide, and would be more amenable to ENaC and aldosterone inhibiting drugs. Activators of BK-α/β1 or BK-α/β4 might be effective blood pressure lowering agents for a subset of hypertensive patients. Inhibitors of renal BK would effectively spare K in patients with Bartter Syndrome, a renal K wasting disease. PMID:24721651

  16. BK-parameter from Nf=2 twisted mass lattice QCD

    International Nuclear Information System (INIS)

    We present an unquenched Nf = 2 lattice computation of the BK parameter which controls K0- anti K0 oscillations. A partially quenched setup is employed with two maximally twisted dynamical (sea) light Wilson quarks, and valence quarks of both the maximally twisted and the Osterwalder-Seiler variety. Suitable combinations of these two kinds of valence quarks lead to a lattice definition of the BK parameter which is both multiplicatively renormalizable and O(a) improved. Employing the non-perturbative RI-MOM scheme, in the continuum limit and at the physical value of the pion mass we get BRGIK=0.729±0.030, a number well in line with the existing quenched and unquenched determinations. (orig.)

  17. Universal features of JIMWLK and BK evolution at small x

    CERN Document Server

    Rummukainen, K; Rummukainen, Kari; Weigert, Heribert

    2004-01-01

    In this paper we present the results of numerical studies of the JIMWLK and BK equations with a particular emphasis on the universal scaling properties and phase space structure involved. The results are valid for near zero impact parameter in DIS. We demonstrate IR safety due to the occurrence of a rapidity dependent saturation scale Q_s(\\tau). Within the set of initial conditions chosen both JIMWLK and BK equations show remarkable agreement. We point out the crucial importance of running coupling corrections to obtain consistency in the UV. Despite the scale breaking induced by the running coupling we find that evolution drives correlators towards an asymptotic form with near scaling properties. We discuss asymptotic features of the evolution, such as the \\tau- and A-dependence of Q_s away from the initial condition.

  18. [Cytomegalovirus and BK polyomavirus infection after renal transplantation].

    Science.gov (United States)

    De Paolis, P; Gervasio, E; Tedesco, M; Favaro', A; Iappelli, M; Di Giulio, S

    2009-01-01

    Cytomegalovirus (CMV) and BK polyomavirus (BKV) infections have been described in a high percentage of renal transplant patients and are known to cause various complications in renal transplantation. They are closely related to immunosuppressive therapy and implicated in the progression of graft failure. This review focuses on the clinical aspects of CMV and BKV infection after renal transplantation, optimal monitoring, and recent preventive measures and interventions to improve graft function and recipient survival. PMID:19382094

  19. Inhibition of Human BK Polyomavirus Replication by Small Noncoding RNAs

    OpenAIRE

    Tikhanovich, I.; Liang, B.; Seoighe, C.; et al.

    2011-01-01

    Small noncoding RNAs regulate a variety of cellular processes, including genomic imprinting, chromatin remodeling, replication, transcription, and translation. Here, we report small replication-regulating RNAs (srRNAs) that specifically inhibit DNA replication of the human BK polyomavirus (BKV) in vitro and in vivo. srRNAs from FM3A murine mammary tumor cells were enriched by DNA replication assay-guided fractionation and hybridization to the BKV noncoding control region (NCCR) and synthesize...

  20. Inhibition of Human BK Polyomavirus Replication by Small Noncoding RNAs▿

    OpenAIRE

    Tikhanovich, Irina; Liang, Bo; Seoighe, Cathal; Folk, William R.; Nasheuer, Heinz Peter

    2011-01-01

    Small noncoding RNAs regulate a variety of cellular processes, including genomic imprinting, chromatin remodeling, replication, transcription, and translation. Here, we report small replication-regulating RNAs (srRNAs) that specifically inhibit DNA replication of the human BK polyomavirus (BKV) in vitro and in vivo. srRNAs from FM3A murine mammary tumor cells were enriched by DNA replication assay-guided fractionation and hybridization to the BKV noncoding control region (NCCR) and synthesize...

  1. Do polyomavirus hominis strains BK and JC play a role in oral squamous cell carcinoma?

    Directory of Open Access Journals (Sweden)

    Dorota Polz

    2015-02-01

    Full Text Available Introduction. Head and neck cancers are the most common cancers worldwide. It is estimated that approximately 90% of all head and neck cancers are represented by squamous cell carcinoma (SCC. There are many risk factors causing this type of cancer, including environmental factors and lifestyle choices, such as tobacco smoking or abusing alcohol. Other important risk factor include infectious factors. [b]Objective[/b]. The aim of this study was to analyze the prevalence of BK and JC virus infections among patients with oral squamous cell carcinoma (OSCC. [b]Materials and method[/b]. The correlation between BKV infection and OSCC, and correlation between BKV, OSCC, alcohol abuse, tobacco smoking, demographic data, pre-treatment staging, metastases of lymph node evidence, and grading, was analyzed. The study group consisted of 92 patients with squamous cell carcinoma (OSCC, 75 males, and 17 females, aged between 40 – 87 (average 56.8. All the patients underwent surgery and were not subjected to chemotherapy or radiotherapy prior to treatment. The analyzed samples were collected from paraffin sections. [b]Results[/b]. BKV DNA was detected in 18.5% of patients with OSCC. In the control group, BKV DNA was detected in 3.3%. BKV DNA was statistically more frequently detected among patients with squamous carcinoma, compared to the control group (p<0.05. [b]Conclusions[/b]. The obtained results suggest that the BKV virus may play an important role in the development of oral squamous cell carcinoma.

  2. BK channel activation by NS11021 decreases excitability and contractility of urinary bladder smooth muscle

    DEFF Research Database (Denmark)

    Layne, Jeffrey J; Nausch, Bernhard; Olesen, Søren-Peter;

    2009-01-01

    activation of BK channels has the converse effect of reducing UBSM excitability and contractility. Here, we have sought to investigate this possibility by using the novel BK channel opener NS11021. NS11021 (3 microM) caused an approximately threefold increase in both single BK channel open probability (P......Large-conductance Ca(2+)-activated potassium (BK) channels play an important role in regulating the function and activity of urinary bladder smooth muscle (UBSM), and the loss of BK channel function has been shown to increase UBSM excitability and contractility. However, it is not known whether......(o)) and whole cell BK channel currents. The frequency of spontaneous action potentials in UBSM strips was reduced by NS11021 from a control value of 20.9 + or - 5.9 to 10.9 + or - 3.7 per minute. NS11021 also reduced the force of UBSM spontaneous phasic contractions by approximately 50%, and this force...

  3. Unique Inner Pore Properties of BK Channels Revealed by Quaternary Ammonium Block

    OpenAIRE

    Li, Weiyan; Aldrich, Richard W.

    2004-01-01

    Potassium channels have a very wide distribution of single-channel conductance, with BK type Ca2+-activated K+ channels having by far the largest. Even though crystallographic views of K+ channel pores have become available, the structural basis underlying BK channels' large conductance has not been completely understood. In this study we use intracellularly applied quaternary ammonium compounds to probe the pore of BK channels. We show that molecules as large as decyltriethylammonium (C10) a...

  4. Pengaruh Sumber Karbon dan Nitrogen Terhadap Pertumbuhan dan Pembentukan Spora Bacillus sp. Bk17

    OpenAIRE

    Rachmi

    2014-01-01

    Study of the effect of carbon and nitrogen sources on the growth and sporulation of Bacillus sp. BK17 has been conducted. Bacillus sp. BK17 was cultured in broth medium containing different carbon and nitrogen sources, and incubated for 6 days. The highest growth of Bacillus sp. BK17 was obtained on molasses-tryptone medium incubated during 3 days and the lowest growth obtained on whey-sodium nitrate. The highest spore formation was also obtained from molasses-tryptone mediu...

  5. Calcium-Activated Potassium (BK) Channels Are Encoded by Duplicate slo1 Genes in Teleost Fishes

    OpenAIRE

    Rohmann, Kevin N.; Deitcher, David L.; Bass, Andrew H.

    2009-01-01

    Calcium-activated, large conductance potassium (BK) channels in tetrapods are encoded by a single slo1 gene, which undergoes extensive alternative splicing. Alternative splicing generates a high level of functional diversity in BK channels that contributes to the wide range of frequencies electrically tuned by the inner ear hair cells of many tetrapods. To date, the role of BK channels in hearing among teleost fishes has not been investigated at the molecular level, although teleosts account ...

  6. Interacting influence of diuretics and diet on BK channel-regulated K homeostasis

    OpenAIRE

    Wen, Donghai; Cornelius, Ryan J.; Sansom, Steven C.

    2013-01-01

    Large conductance, Ca-activated K channels are abundantly located in cells of vasculature, glomerulus and distal nephron, where they are involved in maintaining blood volume, blood pressure and K homeostasis. In mesangial cells and smooth muscle cells of vessels, the BK-α pore associates with BK-β1 subunits and regulates contraction in a Ca-mediated feedback manner. The BK-β1 also resides in connecting tubule cells of the nephron. BK-β1 knockout mice (β1KO) exhibit fluid retention, hypertensi...

  7. Collinearly-improved BK evolution meets the HERA data

    Directory of Open Access Journals (Sweden)

    E. Iancu

    2015-11-01

    Full Text Available In a previous publication, we have established a collinearly-improved version of the Balitsky–Kovchegov (BK equation, which resums to all orders the radiative corrections enhanced by large double transverse logarithms. Here, we study the relevance of this equation as a tool for phenomenology, by confronting it to the HERA data. To that aim, we first improve the perturbative accuracy of our resummation, by including two classes of single-logarithmic corrections: those generated by the first non-singular terms in the DGLAP splitting functions and those expressing the one-loop running of the QCD coupling. The equation thus obtained includes all the next-to-leading order corrections to the BK equation which are enhanced by (single or double collinear logarithms. We then use numerical solutions to this equation to fit the HERA data for the electron–proton reduced cross-section at small Bjorken x. We obtain good quality fits for physically acceptable initial conditions. Our best fit, which shows a good stability up to virtualities as large as Q2=400 GeV2 for the exchanged photon, uses as an initial condition the running-coupling version of the McLerran–Venugopalan model, with the QCD coupling running according to the smallest dipole prescription.

  8. Collinearly-improved BK evolution meets the HERA data

    CERN Document Server

    Iancu, E; Mueller, A H; Soyez, G; Triantafyllopoulos, D N

    2015-01-01

    In a previous publication, we have established a collinearly-improved version of the Balitsky-Kovchegov (BK) equation, which resums to all orders the radiative corrections enhanced by large double transverse logarithms. Here, we study the relevance of this equation as a tool for phenomenology, by confronting it to the HERA data. To that aim, we first improve the perturbative accuracy of our resummation, by including two classes of single-logarithmic corrections: those generated by the first non-singular terms in the DGLAP splitting functions and those expressing the one-loop running of the QCD coupling. The equation thus obtained includes all the next-to-leading order corrections to the BK equation which are enhanced by (single or double) collinear logarithms. We then use numerical solutions to this equation to fit the HERA data for the electron-proton reduced cross-section at small Bjorken x. We obtain good quality fits for physically acceptable initial conditions. Our best fit, which shows a good stability ...

  9. InterProScan Result: BK005919 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available BK005919 BK005919_1_ORF1 CAA510C026AD7115 PANTHER PTHR21137 7tm6_olfct_rcpt 9.800002721303041E-2 ... t binding (GO:0005549)|Biological Process: sensory perception ... of smell (GO:0007608)|Cellular Component: membrane ...

  10. InterProScan Result: BK005919 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available BK005919 BK005919_1_ORF1 CAA510C026AD7115 PFAM PF02949 7tm_6 6.900000000000011E-20 T IPR004117 O ... t binding (GO:0005549)|Biological Process: sensory perception ... of smell (GO:0007608)|Cellular Component: membrane ...

  11. Cochlear function in mice lacking the BK channel alpha, beta1, or beta4 subunits

    NARCIS (Netherlands)

    Pyott, Sonja J; Meredith, Andrea L; Fodor, Anthony A; Vázquez, Ana E; Yamoah, Ebenezer N; Aldrich, Richard W

    2007-01-01

    Large conductance voltage- and calcium-activated potassium (BK) channels are important for regulating many essential cellular functions, from neuronal action potential shape and firing rate to smooth muscle contractility. In amphibians, reptiles, and birds, BK channels mediate the intrinsic frequenc

  12. KCNMA1 encoded cardiac BK channels afford protection against ischemia-reperfusion injury

    DEFF Research Database (Denmark)

    Soltysinska, Ewa; Bentzen, Bo Hjorth; Barthmes, Maria;

    2014-01-01

    Mitochondrial potassium channels have been implicated in myocardial protection mediated through pre-/postconditioning. Compounds that open the Ca2+- and voltage-activated potassium channel of big-conductance (BK) have a pre-conditioning-like effect on survival of cardiomyocytes after ischemia....../reperfusion injury. Recently, mitochondrial BK channels (mitoBKs) in cardiomyocytes were implicated as infarct-limiting factors that derive directly from the KCNMA1 gene encoding for canonical BKs usually present at the plasma membrane of cells. However, some studies challenged these cardio-protective roles of mito......BKs. Herein, we present electrophysiological evidence for paxilline- and NS11021-sensitive BK-mediated currents of 190 pS conductance in mitoplasts from wild-type but not BK-/- cardiomyocytes. Transmission electron microscopy of BK-/- ventricular muscles fibres showed normal ultra-structures and matrix...

  13. Interaction Between Human Polyomavirus BK and Hypoxia Inducible Factor-1 alpha.

    Science.gov (United States)

    Signorini, Lucia; Croci, Mattia; Boldorini, Renzo; Varella, Rafael Brandao; Elia, Francesca; Carluccio, Silvia; Villani, Sonia; Bella, Ramona; Ferrante, Pasquale; Delbue, Serena

    2016-06-01

    BK polyomavirus (BKV) has a worldwide seroprevalence of approximately 90%. After primary infection, BKV establishes a life-long latency within the urogenital tract. The severe immunological impairment occurring in renal transplant recipients leads to BKV reactivation, which may result in polyomavirus associated nephropathy (PVAN). While the transplanted kidney is transiently unperfused, Hypoxia Inducible Factors (HIFs) mediate the cellular response to hypoxia. The α-subunit of HIF isoform 1 (HIF-1α) may interact with several viruses, but until now, there has been no information regarding the interaction between BKV and HIF-1α. The aim of this study is to investigate the possible interaction between HIF-1α and BKV and its potential effect on the pathogenesis of PVAN. Screening of 17 kidney tissue samples revealed that HIF-1α expression was 13.6-fold higher in PVAN tissues compared to control tissues. A luminometric assay in co-transfected African green monkey kidney cells (VERO) demonstrated BKV promoter activation ranging from two to sixfold (P hypoxia, compared to the cells not subjected to hypoxia. Both ex vivo and in vitro interactions between HIF-1α and BKV were observed, suggesting that HIF-1α, stabilized during transplantation, may be able to bind the BKV promoter and enhance BKV replication. Thus, hypoxia should be considered a risk factor for the development of PVAN in kidney transplant recipients. J. Cell. Physiol. 231: 1343-1349, 2016. © 2015 Wiley Periodicals, Inc. PMID:26529465

  14. Covariance fitting of highly correlated $B_K$ data

    CERN Document Server

    Yoon, Boram; Jung, Chulwoo; Lee, Weonjong

    2011-01-01

    We present the reason why we use the diagonal approximation (uncorrelated fitting) when we perform the data analysis of highly correlated $B_K$ data on the basis of the SU(2) staggered chiral perturbation theory. Basically, the essence of the problem is that we do not have enough statistics to determine the small eigenvalues of the covariance matrix with a high precision. As a result, we have the smallest eigenvalue, which is smaller than the statistical error of the covariance matrix, corresponding to an unphysical eigenmode. We have applied a number of prescriptions available in the market such as the cutoff method and modified covariance matrix method. It turns out that the cutoff method is not a good prescription and the modified covariance matrix method is an even worse one. The diagonal approximation turns out to be a good prescription if the data points are somehow correlated and the statistics are relatively poor.

  15. Oxidative Stress and Maxi Calcium-Activated Potassium (BK Channels

    Directory of Open Access Journals (Sweden)

    Anton Hermann

    2015-08-01

    Full Text Available All cells contain ion channels in their outer (plasma and inner (organelle membranes. Ion channels, similar to other proteins, are targets of oxidative impact, which modulates ion fluxes across membranes. Subsequently, these ion currents affect electrical excitability, such as action potential discharge (in neurons, muscle, and receptor cells, alteration of the membrane resting potential, synaptic transmission, hormone secretion, muscle contraction or coordination of the cell cycle. In this chapter we summarize effects of oxidative stress and redox mechanisms on some ion channels, in particular on maxi calcium-activated potassium (BK channels which play an outstanding role in a plethora of physiological and pathophysiological functions in almost all cells and tissues. We first elaborate on some general features of ion channel structure and function and then summarize effects of oxidative alterations of ion channels and their functional consequences.

  16. Expression of BK Ca channels and the modulatory beta-subunits in the rat and porcine trigeminal ganglion

    DEFF Research Database (Denmark)

    Johansson, Helle Wulf; Hay-Schmidt, Anders; Poulsen, Asser Nyander; Klærke, Dan Arne; Olesen, Jes; Jansen-Olesen, Inger

    2009-01-01

    cerebral arteries. We hypothesize that BK(Ca) channel alpha- and beta-subunits are present in the rat and porcine trigeminal ganglion (TG) thus enabling a role in migraine. BK(Ca) channel mRNA was detected using reverse transcription polymerase chain reaction (RT-PCR) and in situ hybridization. BK...

  17. Fusion and quasifission dynamics in the reactions $^{48}$Ca+$^{249}$Bk and $^{50}$Ti+$^{249}$Bk using TDHF

    CERN Document Server

    Umar, A S; Simenel, C

    2016-01-01

    Background: Synthesis of superheavy elements (SHE) with fusion-evaporation reactions is strongly hindered by the quasifission (QF) mechanism which prevents the formation of an equilibrated compound nucleus and which depends on the structure of the reactants. New SHE have been recently produced with doubly-magic $^{48}$Ca beams. However, SHE synthesis experiments with single-magic $^{50}$Ti beams have so far been unsuccessful. Purpose: In connection with experimental searches for $Z=117,119$ superheavy elements, we perform a theoretical study of fusion and quasifission mechanisms in $^{48}$Ca,$^{50}$Ti+$^{249}$Bk reactions in order to investigate possible differences in reaction mechanisms induced by these two projectiles. Methods: The collision dynamics and the outcome of the reactions are studied using unrestricted time-dependent Hartree-Fock (TDHF) calculations as well as the density-constrained TDHF method to extract the nucleus-nucleus potentials and the excitation energy in each fragment. Results: Nucleu...

  18. Adrenaline-induced colonic K+ secretion is mediated by KCa1.1 (BK) channels

    DEFF Research Database (Denmark)

    Sørensen, Mads Vaarby; Sausbier, Matthias; Ruth, Peter;

    2010-01-01

    anion secretion and a smaller electrically opposing K(+) secretion. Using tissue from (i) BK wildtype (BK(+/+)) and knockout (BK(/)) and (ii) cystic fibrosis transmembrane regulator (CFTR) wildtype (CFTR(+/+)) and knockout (CFTR(/)) mice we were able to isolate the adrenaline-induced K(+) secretion. We...... found that adrenaline-induced K(+) secretion: (1) is absent in colonic epithelia from BK(/) mice, (2) is greatly up-regulated in mice on a high K(+) diet and (3) is present as sustained positive current in colonic epithelia from CFTR(/) mice. We identified two known C-terminal BK alpha-subunit splice...

  19. Bk and Cf chromatographic separation and 249Bk/248Cm and 249Cf/248Cm elemental ratios determination by inductively coupled plasma quadrupole mass spectrometry

    International Nuclear Information System (INIS)

    The French Atomic Energy Commission has carried out several experiments for the study of minor-actinide transmutation processes in high intensity thermal neutron flux. In this context a Cm sample enriched in 248Cm (97%) was irradiated in a thermal neutron flux at the High Flux Reactor (HFR) of the Laue-Langevin Institute (ILL). The precise and accurate determination of Cf isotope ratios and of 249Bk/248Cm and 249Cf/248Cm elemental ratios in the 248Cm irradiated sample is crucial for the calculation of actinide neutron capture cross-sections.This work describes an analytical procedure for the separation and the isotope ratio measurement of Bk and Cf in the irradiated sample.The Bk and Cf separation is based on a lanthanides separation protocol previously developed by the laboratory. Well-defined retention times for Bk and Cf were obtained by coupling the Ionic Chromatography (IC) with an ICP-QMS. All conditions of element separation by IC and the different steps of the analytical protocol in order to obtain the isotopic and elemental ratios are presented. Relative uncertainties of Cf isotopic ratios range from 0.3% to 0.5% and the uncertainty of the 249Bk/248Cm and 249Cf/248Cm elemental ratios are respectively 6.1% and 3.2%.This level of uncertainty for both isotopic and elemental ratios is in perfect agreement with the requirement for transmutation studies. (authors)

  20. Clinical polyomavirus BK variants with agnogene deletion are non-functional but rescued by trans-complementation

    International Nuclear Information System (INIS)

    High-level replication of polyomavirus BK (BKV) in kidney transplant recipients is associated with the emergence of BKV variants with rearranged (rr) non-coding control region (NCCR) increasing viral early gene expression and cytopathology. Cloning and sequencing revealed the presence of a BKV quasispecies which included non-functional variants when assayed in a recombinant virus assay. Here we report that the rr-NCCR of BKV variants RH-3 and RH-12, both bearing a NCCR deletion including the 5' end of the agnoprotein coding sequence, mediated early and late viral reporter gene expression in kidney cells. However, in a recombinant virus they failed to produce infectious progeny despite large T-antigen and VP1 expression and the formation of nuclear virus-like particles. Infectious progeny was generated when the agnogene was reconstructed in cis or agnoprotein provided in trans from a co-existing BKV rr-NCCR variant. We conclude that complementation can rescue non-functional BKV variants in vitro and possibly in vivo.

  1. Prevalence of JC and BK polyomavirus excretion in the urine of HIV-infected patients from Serbia

    Directory of Open Access Journals (Sweden)

    Karalić Danijela

    2014-01-01

    Full Text Available BK virus (BKV and JC virus (JCV persist as latent infection in the kidneys. Reactivation of both viruses may be linked to immunodeficiency. The aims of this study were to determine the prevalence of BKV and JCV viruria and to evaluate the relationship between immunodeficiency and viruria in a cohort of HIV-infected patients. Urine samples from 93 HIV-infected patients were collected and tested for the presence of BKV and JCV DNA by PCR. The overall prevalence of polyomavirus DNA in urine was 74.2%. BKV DNA was detected in 30.1% urine samples and JCV DNA in 23.7% samples. Both BKV and JCV DNA were detected in 20.4% samples. There was no association between BKV/JCV urinary shedding and the degree of immunosuppression measured by CD4+ cell count. However, taking into account the severity of disease resulting from reactivation of BKV and JCV, patients with HIV/polyomavirus co-infection should be kept under frequent and regular supervision. [Projekat Ministarstva nauke Republike Srbije, br. 175073

  2. BK channels in microglia are required for morphine-induced hyperalgesia.

    Science.gov (United States)

    Hayashi, Yoshinori; Morinaga, Saori; Zhang, Jing; Satoh, Yasushi; Meredith, Andrea L; Nakata, Takahiro; Wu, Zhou; Kohsaka, Shinichi; Inoue, Kazuhide; Nakanishi, Hiroshi

    2016-01-01

    Although morphine is a gold standard medication, long-term opioid use is associated with serious side effects, such as morphine-induced hyperalgesia (MIH) and anti-nociceptive tolerance. Microglia-to-neuron signalling is critically involved in pain hypersensitivity. However, molecules that control microglial cellular state under chronic morphine treatment remain unknown. Here we show that the microglia-specific subtype of Ca(2+)-activated K(+) (BK) channel is responsible for generation of MIH and anti-nociceptive tolerance. We find that, after chronic morphine administration, an increase in arachidonic acid levels through the μ-opioid receptors leads to the sole activation of microglial BK channels in the spinal cord. Silencing BK channel auxiliary β3 subunit significantly attenuates the generation of MIH and anti-nociceptive tolerance, and increases neurotransmission after chronic morphine administration. Therefore, microglia-specific BK channels contribute to the generation of MIH and anti-nociceptive tolerance. PMID:27241733

  3. Polyomavirus BK-specific immunity after kidney transplantation.

    Science.gov (United States)

    Comoli, Patrizia; Azzi, Alberta; Maccario, Rita; Basso, Sabrina; Botti, Gerardo; Basile, Giancarlo; Fontana, Iris; Labirio, Massimo; Cometa, Angela; Poli, Francesca; Perfumo, Francesco; Locatelli, Franco; Ginevri, Fabrizio

    2004-10-27

    Failure to mount or maintain a protective immune response may influence the development of polyomavirus BK (BKV)-associated nephropathy (PVAN). However, limited data are so far available on BKV-specific immunity after kidney transplantation. BKV-specific cellular immune response was retrospectively analyzed in kidney recipients with or without BKV infection/reactivation by measuring the frequency of interferon (IFN)-gamma-secreting cells in peripheral blood. Patients with BKV-active infection and good renal function (n=6) had a mean BKV-specific lymphocyte frequency 2 log lower than healthy controls and in the same range as BKV-seropositive recipients without active infection (n=7). Patients with PVAN (n=5) revealed undetectable levels of BKV-specific cells. However, two patients from the latter cohort treated with immunosuppression reduction showed the emergence of specific immunity, with IFN-gamma production in the same range as healthy controls. Our preliminary data suggest that lack of protective immunity toward BKV may favor the occurrence of BKV active infection and influence the progression to PVAN. PMID:15502726

  4. Froth characteristic of MIBC and BK-201 frothers%起泡剂MIBC和BK-201的浮选泡沫特性

    Institute of Scientific and Technical Information of China (English)

    曾培; 欧乐明; 冯其明; 李洪强; 张福亚

    2015-01-01

    选用非极性基结构不同的起泡剂MIBC和BK-201,利用自制的泡沫性能测试系统,在两相泡沫体系下,测定两相泡沫不同高度处的气泡直径、静压强、表观溢流速度,研究起泡剂对泡沫特征及夹带的影响.结果表明:增加起泡剂浓度,气泡的兼并行为受到抑制,气泡直径逐渐减小;当MIBC浓度超过75 mg/L、BK-201浓度超过150 mg/L时,兼并行为受到显著抑制,气泡直径基本保持不变.在相同的浓度下,相比MIBC,BK-201产生的泡沫气泡直径大、含液率低、水回收速率低.因而,微细粒脉石在BK-201所形成泡沫中夹带更弱,浮选选择性更好.%By using self-designed foam property testing system, two nonpolar base structure frothers, MIBC and BK-201 were chosen to study the influences of frothers on the foam characteristic and entrainment by measuring the bubble diameter, static pressure and apparent flooding velocity in the two-phase foam. The results show that bubble merger degree reduces and air bubble diameter decreases with increasing frothers concentration. When the concentrations of MIBC and BK-201 are more than 75 and 150 mg/L, respectively, the air bubble diameter basically remains unchanged because the merger behavior is dramatically depressed. Under the same concentration, BK-201 generates larger diameter bubble, lower liquid holdup and lower water recovery compared with MIBC. As a result, the foam entrainment of fine gangue is weaker and the selectivity of flotation is better when BK-201 is used.

  5. BK channel β1 and β4 auxiliary subunits exert opposite influences on escalated ethanol drinking in dependent mice.

    Science.gov (United States)

    Kreifeldt, Max; Le, David; Treistman, Steven N; Koob, George F; Contet, Candice

    2013-01-01

    Large conductance calcium-activated potassium (BK) channels play a key role in the control of neuronal activity. Ethanol is a potent activator of BK channel gating, but how this action may impact ethanol drinking still remains poorly understood. Auxiliary β subunits are known to modulate ethanol-induced potentiation of BK currents. In the present study, we investigated whether BK β1 and β4 subunits influence voluntary ethanol consumption using knockout (KO) mice. In a first experiment, mice were first subjected to continuous two-bottle choice (2BC) and were then switched to intermittent 2BC, which progressively increased ethanol intake as previously described in wildtype mice. BK β1 or β4 subunit deficiency did not affect ethanol self-administration under either schedule of access. In a second experiment, mice were first trained to drink ethanol in a limited-access 2BC paradigm. BK β1 or β4 deletion did not affect baseline consumption. Weeks of 2BC were then alternated with weeks of chronic intermittent ethanol (CIE) or air inhalation. As expected, a gradual escalation of ethanol drinking was observed in dependent wildtype mice, while intake remained stable in non-dependent wildtype mice. However, CIE exposure only produced a mild augmentation of ethanol consumption in BK β4 KO mice. Conversely, ethanol drinking increased after fewer CIE cycles in BK β1 KO mice than in wildtype mice. In conclusion, BK β1 or β4 did not influence voluntary ethanol drinking in non-dependent mice, regardless of the pattern of access to ethanol. However, deletion of BK β4 attenuated, while deletion of BK β1 accelerated, the escalation of ethanol drinking during withdrawal from CIE. Our data suggest that BK β1 and β4 subunits have an opposite influence on the negative reinforcing properties of ethanol withdrawal. Modulating the expression, distribution or interactions of BK channel auxiliary subunits may therefore represent a novel avenue for the treatment of alcoholism

  6. BK channel β1 and β4 auxiliary subunits exert opposite influences on escalated ethanol drinking in dependent mice

    Directory of Open Access Journals (Sweden)

    Max eKreifeldt

    2013-12-01

    Full Text Available Large conductance calcium-activated potassium (BK channels play a key role in the control of neuronal activity. Ethanol is a potent activator of BK channel gating, but how this action may impact ethanol drinking still remains poorly understood. Auxiliary β subunits are known to modulate ethanol-induced potentiation of BK currents. In the present study, we investigated whether BK β1 and β4 subunits influence voluntary ethanol consumption using knockout mice. In a first experiment, mice were first subjected to continuous two-bottle choice (2BC and were then switched to intermittent 2BC, which progressively increased ethanol intake as previously described in wildtype mice. BK β1 or β4 subunit deficiency did not affect ethanol self-administration under either schedule of access. In a second experiment, mice were first trained to drink ethanol in a limited-access 2BC paradigm. BK β1 or β4 deletion did not affect baseline consumption. Weeks of 2BC were then alternated with weeks of chronic intermittent ethanol (CIE or air inhalation. As expected, a gradual escalation of ethanol drinking was observed in dependent wildtype mice, while intake remained stable in non-dependent wildtype mice. However, CIE exposure only produced a mild augmentation of ethanol consumption in BK β4 knockout mice. Conversely, ethanol drinking increased after fewer CIE cycles in BK β1 knockout mice than in wildtype mice. In conclusion, BK β1 or β4 did not influence voluntary ethanol drinking in non-dependent mice, regardless of the pattern of access to ethanol. However, deletion of BK β4 attenuated, while deletion of BK β1 accelerated, the escalation of ethanol drinking during withdrawal from CIE. Our data suggest that BK β1 and β4 subunits have an opposite influence on the negative reinforcing properties of ethanol withdrawal. Modulating the expression, distribution or interactions of BK channel auxiliary subunits may therefore represent a novel avenue for the

  7. Molecular basis for differential modulation of BK channel voltage-dependent gating by auxiliary γ subunits.

    Science.gov (United States)

    Li, Qin; Fan, Fei; Kwak, Ha Rim; Yan, Jiusheng

    2015-06-01

    Large conductance Ca(2+)- and voltage-activated potassium (BK) channels are comprised of pore-forming α subunits and various regulatory auxiliary subunits. The BK channel auxiliary γ (BKγ) subunits are a newly identified class of proteins containing an extracellular leucine-rich repeat domain (LRRD), a single transmembrane (TM) segment, and a short cytoplasmic C-terminal tail (C-tail). Although each of the four BKγ proteins shifts the voltage dependence of BK channel activation in a hyperpolarizing direction, they show markedly different efficacies, mediating shifts over a range of 15-145 mV. Analyses of chimeric BKγ subunits created by swapping individual structural elements, and of BKγ deletion and substitution mutants, revealed that differential modulation of BK gating by the four BKγ subunits depends on a small region consisting of the TM segment and the adjacent intracellular cluster of positively charged amino acids. The γ1 and γ2 TM segments contributed approximately -100 mV, and the γ1 and γ3 C-tails contributed approximately -40 mV, to shifting the voltage dependence of BK channel activation, whereas the γ3 and γ4 TM segments and the γ2 and γ4 C-tails contributed much less. The large extracellular LRRDs were mainly functionally interchangeable, although the γ1 LRRD was slightly less effective at enhancing (or slightly more effective at attenuating) the shift in BK channel voltage-dependent gating toward hyperpolarizing potentials than those of the other BKγ subunits. Analysis of mutated BKγ subunits revealed that juxta-membrane clusters of positively charged amino acids determine the functions of the γ1 and γ3 C-tails. Therefore, the modulatory functions of BKγ subunits are coarse- and fine-tuned, respectively, through variations in their TM segments and in the adjacent intracellular positively charged regions. Our results suggest that BK channel modulation by auxiliary γ subunits depends on intra- and/or juxta-membrane mechanisms

  8. BK K+ channel blockade inhibits radiation-induced migration/brain infiltration of glioblastoma cells.

    Science.gov (United States)

    Edalat, Lena; Stegen, Benjamin; Klumpp, Lukas; Haehl, Erik; Schilbach, Karin; Lukowski, Robert; Kühnle, Matthias; Bernhardt, Günther; Buschauer, Armin; Zips, Daniel; Ruth, Peter; Huber, Stephan M

    2016-03-22

    Infiltration of the brain by glioblastoma cells reportedly requires Ca2+ signals and BK K+ channels that program and drive glioblastoma cell migration, respectively. Ionizing radiation (IR) has been shown to induce expression of the chemokine SDF-1, to alter the Ca2+ signaling, and to stimulate cell migration of glioblastoma cells. Here, we quantified fractionated IR-induced migration/brain infiltration of human glioblastoma cells in vitro and in an orthotopic mouse model and analyzed the role of SDF-1/CXCR4 signaling and BK channels. To this end, the radiation-induced migratory phenotypes of human T98G and far-red fluorescent U-87MG-Katushka glioblastoma cells were characterized by mRNA and protein expression, fura-2 Ca2+ imaging, BK patch-clamp recording and transfilter migration assay. In addition, U-87MG-Katushka cells were grown to solid glioblastomas in the right hemispheres of immunocompromised mice, fractionated irradiated (6 MV photons) with 5 × 0 or 5 × 2 Gy, and SDF-1, CXCR4, and BK protein expression by the tumor as well as glioblastoma brain infiltration was analyzed in dependence on BK channel targeting by systemic paxilline application concomitant to IR. As a result, IR stimulated SDF-1 signaling and induced migration of glioblastoma cells in vitro and in vivo. Importantly, paxilline blocked IR-induced migration in vivo. Collectively, our data demonstrate that fractionated IR of glioblastoma stimulates and BK K+ channel targeting mitigates migration and brain infiltration of glioblastoma cells in vivo. This suggests that BK channel targeting might represent a novel approach to overcome radiation-induced spreading of malignant brain tumors during radiotherapy. PMID:26893360

  9. Pharmacological consequences of the coexpression of BK channel α and auxiliary β subunits

    Science.gov (United States)

    Torres, Yolima P.; Granados, Sara T.; Latorre, Ramón

    2014-01-01

    Coded by a single gene (Slo1, KCM) and activated by depolarizing potentials and by a rise in intracellular Ca2+ concentration, the large conductance voltage- and Ca2+-activated K+ channel (BK) is unique among the superfamily of K+ channels. BK channels are tetramers characterized by a pore-forming α subunit containing seven transmembrane segments (instead of the six found in voltage-dependent K+ channels) and a large C terminus composed of two regulators of K+ conductance domains (RCK domains), where the Ca2+-binding sites reside. BK channels can be associated with accessory β subunits and, although different BK modulatory mechanisms have been described, greater interest has recently been placed on the role that the β subunits may play in the modulation of BK channel gating due to its physiological importance. Four β subunits have currently been identified (i.e., β1, β2, β3, and β4) and despite the fact that they all share the same topology, it has been shown that every β subunit has a specific tissue distribution and that they modify channel kinetics as well as their pharmacological properties and the apparent Ca2+ sensitivity of the α subunit in different ways. Additionally, different studies have shown that natural, endogenous, and synthetic compounds can modulate BK channels through β subunits. Considering the importance of these channels in different pathological conditions, such as hypertension and neurological disorders, this review focuses on the mechanisms by which these compounds modulate the biophysical properties of BK channels through the regulation of β subunits, as well as their potential therapeutic uses for diseases such as those mentioned above. PMID:25346693

  10. Role of JC Virus Agnoprotein in DNA Repair

    OpenAIRE

    Darbinyan, Armine; Siddiqui, Khwaja M.; Slonina, Dorota; Darbinian, Nune; Amini, Shohreh; White, Martyn K.; Khalili, Kamel

    2004-01-01

    The late region of human neurotropic JC virus encodes a small 71-amino-acid agnoprotein that is also found in the polyomaviruses simian virus 40 and BK virus. Several functions of agnoprotein have been identified, including roles in regulating viral transcription and virion maturation. Earlier studies showed that agnoprotein expressed alone induced p21/WAF-1 expression and caused cells to accumulate in the G2/M stage of the cell cycle. Here we report that agnoprotein expression sensitized cel...

  11. Tuning the mechanosensitivity of a BK channel by changing the linker length

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Some large-conductance Ca2+ and voltage-activated K+ (BK) channels are activated by membrane stretch. However, the mechanism of mechano-gating of the BK channels is still not well understood. Previous studies have led to the proposal that the tinker-gating ring complex functions as a passive spring, transducing the force generated by intraceilular Ca2+ to the gate to open the channel. This raises the question as to whether membrane stretch is also transmitted to the gate of mechanosensitive (MS) BK channels via the tinker-gating complex. To study this, we changed the linker length in the stretch-activated BK channel (SAKCaC), and examined the effect of membrane stretch on the gating of the resultant mutant channels. Shortening the tinker increased, whereas extending the tinker reduced, the channel mechanosensitivity both in the presence and in the absence of intracellular Ca2+. However, the voltage and Ca2+ sensitivities were not significantly altered by membrane stretch. Furthermore, the SAKCaC became less sensitive to membrane stretch at relatively high intracellular Ca2+ concentrations or membrane depolarization. These observations suggest that once the channel is in the open-state conformation, tension on the spring is partially released and membrane stretch is less effective. Our results are consistent with the idea that membrane stretch is transferred to the gate via the tinker-gating ring complex of the MS BK channels.

  12. Fusion and quasifission dynamics in the reactions 48Ca+249Bk and 50Ti+249Bk using a time-dependent Hartree-Fock approach

    Science.gov (United States)

    Umar, A. S.; Oberacker, V. E.; Simenel, C.

    2016-08-01

    Background: Synthesis of superheavy elements (SHEs) with fusion-evaporation reactions is strongly hindered by the quasifission (QF) mechanism which prevents the formation of an equilibrated compound nucleus and which depends on the structure of the reactants. New SHEs have been recently produced with doubly-magic 48Ca beams. However, SHE synthesis experiments with single-magic 50Ti beams have so far been unsuccessful. Purpose: In connection with experimental searches for Z =117 ,119 superheavy elements, we perform a theoretical study of fusion and quasifission mechanisms in 48Ca,50Ti+249Bk reactions in order to investigate possible differences in reaction mechanisms induced by these two projectiles. Methods: The collision dynamics and the outcome of the reactions are studied using unrestricted time-dependent Hartree-Fock (TDHF) calculations as well as the density-constrained TDHF method to extract the nucleus-nucleus potentials and the excitation energy in each fragment. Results: Nucleus-nucleus potentials, nuclear contact times, masses and charges of the fragments, as well as their kinetic and excitation energies strongly depend on the orientation of the prolate 249Bk nucleus. Long contact times associated with fusion are observed in collisions of both projectiles with the side of the 249Bk nucleus, but not on collisions with its tip. The energy and impact parameter dependencies of the fragment properties, as well as their mass-angle and mass-total kinetic energy correlations are investigated. Conclusions: Entrance channel reaction dynamics are similar with both 48Ca and 50Ti projectiles. Both are expected to lead to the formation of a compound nucleus by fusion if they have enough energy to get in contact with the side of the 249Bk target.

  13. Molecular investigations of BK(Ca) channels and the modulatory beta-subunits in porcine basilar and middle cerebral arteries

    DEFF Research Database (Denmark)

    Johansson, Helle Wulf; Hay-Schmidt, Anders; Poulsen, Asser Nyander;

    2009-01-01

    Large conductance calcium-activated potassium (BK(Ca)) channels are fundamental in the regulation of cerebral vascular basal tone. We investigated the expression of the mRNA transcripts for the BK(Ca) channel and its modulatory beta-subunits (beta1-beta4) in porcine basilar and middle cerebral...

  14. Airway Hydration, Apical K(+) Secretion, and the Large-Conductance, Ca(2+)-activated and Voltage-dependent Potassium (BK) Channel.

    Science.gov (United States)

    Kis, Adrian; Krick, Stefanie; Baumlin, Nathalie; Salathe, Matthias

    2016-04-01

    Large-conductance, calcium-activated, and voltage-gated K(+) (BK) channels are expressed in many tissues of the human body, where they play important roles in signaling not only in excitable but also in nonexcitable cells. Because BK channel properties are rendered in part by their association with four β and four γ subunits, their channel function can differ drastically, depending on in which cellular system they are expressed. Recent studies verify the importance of apically expressed BK channels for airway surface liquid homeostasis and therefore of their significant role in mucociliary clearance. Here, we review evidence that inflammatory cytokines, which contribute to airway diseases, can lead to reduced BK activity via a functional down-regulation of the γ regulatory subunit LRRC26. Therefore, manipulation of LRRC26 and pharmacological opening of BK channels represent two novel concepts of targeting epithelial dysfunction in inflammatory airway diseases. PMID:27115952

  15. The Disappearance of the Red Supergiant Progenitor of Supernova 2008bk

    OpenAIRE

    Mattila, Seppo; Smartt, Stephen; Maund, Justyn; Benetti, Stefano; Ergon, Mattias

    2010-01-01

    Massive stars end their lives in spectacular supernova explosions. Identifying the progenitor star is a test of stellar evolution and explosion models. Here we show that the progenitor star of the supernova SN 2008bk has now disappeared, which provides conclusive evidence that this was the death of a red supergiant star.

  16. New properties of BK-spaces defined by using regular matrix of Fibonacci numbers

    Science.gov (United States)

    Ercan, Sinan; Bektaş, ćiǧdem A.

    2016-06-01

    In the present paper, we studied the new properties of BK-spaces which were defined using regular matrix of Fibonacci numbers in [1]. We computed alpha-, beta-, gamma- duals of these spaces and obtained Schauder basis. We also derived some topological properties of these spaces.

  17. Evaluation of polyomavirus BK reactivation in lupus patients who underwent kidney transplantation

    Directory of Open Access Journals (Sweden)

    Cristina Costa

    2012-06-01

    Full Text Available Background. A pathogenic role for polyomavirus BK in systemic lupus erythematosus (SLE has been proposed, however no study evaluated the occurrence of BK replication in renal transplant recipients according to the underlying disease leading to transplantation and its potential impact. Methods. The occurrence of BK reactivation was serially evaluated in 468 renal transplant recipients, including 11 patients with SLE as underlying disease (overall, 2370 serum and 2370 urine specimens; 65 from SLE patients. Results. Considering the overall occurrence of viral reactivation (viremia and/or viruria, 26/65 (40% specimens were positive in four SLE patients (36.3% versus 331/2143 (15.4% in 130/227 (57.3% non-SLE patients. A patient transplanted for class III lupus nephritis evidenced sustained BK viremia and viruria (with viremia values potentially indicative of polyomavirus-associated nephropathy in the absence of clinical features of renal dysfunction or recurrence of lupus nephritis. Conclusions. Further studies on larger populations and for a longer follow-up should be required to evaluate the impact of BKV reactivation in renal transplant patients with SLE as underlying disease, as well as the potential therapeutic implications.

  18. Differential expression of BK channel isoforms and beta-subunits in rat neuro-vascular tissues

    DEFF Research Database (Denmark)

    Poulsen, Asser Nyander; Johansson, Helle Wulf; Hay-Schmidt, Anders;

    2009-01-01

    We investigated the expression of splice variants and beta-subunits of the BK channel (big conductance Ca(2+)-activated K(+) channel, Slo1, MaxiK, K(Ca)1.1) in rat cerebral blood vessels, meninges, trigeminal ganglion among other tissues. An alpha-subunit splice variant X1(+24) was found expressed...

  19. Molecular studies of BKCa channels in intracranial arteries

    DEFF Research Database (Denmark)

    Wulf, Helle; Hay-Schmidt, Anders; Poulsen, Asser Nyander;

    2008-01-01

      Large conductance calcium-activated potassium channels (BK(ca)) are crucial for the regulation of cerebral vascular basal tone and might be involved in cerebral vasodilation relevant to migraine and stroke. We studied the differential gene expression of mRNA transcript levels and protein...

  20. BK and JC virus infections in healthy patients compared to kidney transplant recipients in Tunisia.

    Science.gov (United States)

    Boukoum, Hanen; Nahdi, Imen; Sahtout, Wissal; Skiri, Habib; Segondy, Michel; Aouni, Mahjoub

    2016-08-01

    The human polyomaviruses BKPyV and JCPyV are members of Polyomaviridae family and after primary infections they persist as latent infection especially in the kidneys. BKVPy reactivation is mainly related to a renal nephropathy and JCV reactivation can induce the progressive multifocal leukoencephalopathy. The aim of this study was to investigate and to compare the presence of BKPyV and JCPyV in urine and plasma samples from immunocompromised and immunocompetent groups. The viral detection and quantification was done by a real time PCR from 100 healthy individuals and from 72 kidney transplanted patients (KTx) enrolled in a prospective study. Polyomavirus DNA urinary shedding was identified in 19% of healthy person, BKPyV in 6%; JCPyV more frequent in 13%. No individuals in this group developed polyomavirus viremia. BKPyV and JCPyV viruria was seen in 36% and 28% of KTx respectively, and 11% had a concomitant BKPyV and JCPyV viruria. Only BKPy viremia was detected in 5.5% of the KTx. In healthy persons, JCPyV shedding was associated with older individuals. However, in KTx, BKPyV was associated with younger age and male gender. No significant association was found between the patient's origin and BKPyV or JCPyV infection. In conclusion and consisting with previous reports, BKPyV and JCPyV prevalence and urinary loads were significantly higher in immunosuppressed compared to non-immunosuppressed individuals. In Addition and by contrast to KTx, JCPyV was more frequent than BKPyV in healthy individuals. Furthermore, the shedding of both polyomaviruses was differently associated with the age and the sex according to each population. PMID:27317859

  1. Surveillance of polyomavirus BK in relation to immunosuppressive therapy in kidney transplantation

    Directory of Open Access Journals (Sweden)

    Cristina Costa

    2012-03-01

    Full Text Available Introduction. Reactivation of polyomavirus BK in kidney transplant recipients has been associated to the development of nephropathy (polyomavirus-associated nephropathy, PVAN, possibly leading to the loss of the transplanted organ. Immunosuppression is the condicio sine qua non for the onset of PVAN; however, a lower incidence of BK viremia has been reported with low-level tacrolimus based immunosuppressive protocols in comparison to cyclosporine A.Aim of this study was to compare the two immunosuppressive protocols. Methods. Virological monitoring of BK was performed in 468 consecutive renal transplant patients over a period of 3 years (2370 urine e 2370 serum specimens: in particular, 1780 specimens from 362 patients treated with tacrolimus and 590 from 106 treated with cyclosporine A. Results. BK viremia was evidenced in 124 (7.0% and 12 (2.0% specimens from 40 (11.0% and 11 (10.4% patients treated with tacrolimus and cyclosporine A, respectively; similarly, BK viruria in 289 (16.2% and 58 (9.8% specimens from 67 (18.5% and 27 (25.5% patients, being the difference of incidence highly significant (p <0.0001 for both viremia and viruria at comparison between specimens and not significant for patients. No case of PVAN was diagnosed at histophatology evaluation. Conclusions. The incidence of viremia and viruria was similar to that previously reported. Our results evidenced that with low-level tacrolimus-based protocols the overall incidence of reactivation in renal transplant patients is not significantly different and there is no increased risk of PVAN, nevertheless the higher incidence of episodes of reactivation.

  2. Similar enhancement of BK(Ca) channel function despite different aerobic exercise frequency in aging cerebrovascular myocytes.

    Science.gov (United States)

    Li, N; Liu, B; Xiang, S; Shi, L

    2016-07-18

    Aerobic exercise showed beneficial influence on cardiovascular systems in aging, and mechanisms underlying vascular adaption remain unclear. Large-conductance Ca(2+)-activated K(+) (BK(Ca)) channels play critical roles in regulating cellular excitability and vascular tone. This study determined the effects of aerobic exercise on aging-associated functional changes in BK(Ca) channels in cerebrovascular myocytes, Male Wistar rats aged 20-22 months were randomly assigned to sedentary (O-SED), low training frequency (O-EXL), and high training frequency group (O-EXH). Young rats were used as control. Compared to young rats, whole-cell BK(Ca) current was decreased, and amplitude of spontaneous transient outward currents were reduced. The open probability and Ca(2+)/voltage sensitivity of single BK(Ca) channel were declined in O-SED, accompanied with a reduction of tamoxifen-induced BK(Ca) activation; the mean open time of BK(Ca) channels was shortened whereas close time was prolonged. Aerobic exercise training markedly alleviated the aging-associated decline independent of training frequency. Exercise three times rather than five times weekly may be a time and cost-saving training volume required to offer beneficial effects to offset the functional declines of BK(Ca) during aging. PMID:27070745

  3. Ethanol modulation of mammalian BK channels in excitable tissues: molecular targets and their possible contribution to alcohol-induced altered behavior

    Directory of Open Access Journals (Sweden)

    Alex M. Dopico

    2014-12-01

    Full Text Available In most tissues, the function of calcium- and voltage-gated potassium (BK channels is modified in response to ethanol concentrations reached in human blood during alcohol intoxication. In general, modification of BK current from ethanol-naïve preparations in response to brief ethanol exposure results from changes in channel open probability without modification of unitary conductance or change in BK protein levels in the membrane. Protracted and/or repeated ethanol exposure, however, may evoke changes in BK expression. The final ethanol effect on BK open probability leading to either BK current potentiation or BK current reduction is determined by an orchestration of molecular factors, including levels of activating ligand (cytosolic calcium, BK subunit composition and posttranslational modifications, and the channel’s lipid microenvironment. These factors seem to allosterically regulate a direct interaction between ethanol and a recognition pocket of discrete dimensions recently mapped to the channel-forming (slo1 subunit. Type of ethanol exposure also plays a role in the final BK response to the drug: in several central nervous system regions (e.g., striatum, primary sensory neurons, and supraoptic nucleus, acute exposure to ethanol reduces neuronal excitability by enhancing BK activity. In contrast, protracted or repetitive ethanol administration may alter BK subunit composition and membrane expression, rendering the BK complex insensitive to further ethanol exposure. In neurohypophysial axon terminals, ethanol potentiation of BK channel activity leads to a reduction in neuropeptide release. In vascular smooth muscle, however, ethanol inhibition of BK current leads to cell contraction and vascular constriction.

  4. Inhibition of intestinal motility by the putative BK(Ca) channel opener LDD175.

    Science.gov (United States)

    Dela Peña, Ike Campomayor; Yoon, Seo Young; Kim, Sung Mok; Lee, Geum Seon; Park, Chul-Seung; Kim, Yong Chul; Cheong, Jae Hoon

    2009-03-01

    LDD175 (4-chloro-7-trifluoromethyl-10H-benzo[4,5]furo[3,2-b]indole-1-carboxylic acid) is a benzofuroindole compound characterized previously as a potent opener of the large conductance calcium activated (BK(Ca)) channels. Activators of the BK(Ca) channels are potential therapies for smooth muscle hyperactivity disorders. The present study investigates the influence of LDD175 on the mechanical activity of the ileum smooth muscle. LDD175 inhibited spontaneous contractions of the ileum in a concentration-dependent manner (pEC(50)=5.9 +/- 0.1) (E (max)=96 +/- 1.0% at 100 muM, n=3). It also remarkably inhibited contractions due to acetylcholine (ACh) (pEC(50)=5.3 +/- 0.1)(E (max)=97.7 +/- 2.3%, n=6) and electrical field stimulation (EFS) (pEC(50)=5.5 +/- 0.1) (E (max)=83.3 +/- 6.0%, n=6). In strips precontracted by 20 mM KCl, LDD175 significantly reduced the contractions yielding a pEC(50) of 6.1 +/- 0.1 and E (max) of 96.6 +/- 0.9%, (n=6). In 60 mM KCl, a concentration-dependent inhibition was observed with respective pEC(50) and E (max) values of 4.1 +/- 0.1 and 50.8 +/- 5.0% (n=3). BK(Ca) channel blockers iberiotoxin (IbTX) and tetraethylammonium chloride (TEA, 1 mM) attenuated the relaxative effect of LDD175 but not barium chloride (BaCl(2)), and glibenclamide (K(IR) and K(ATP) channel blockers, respectively). These data demonstrate the antispasmodic activity of LDD175 attributable to the potentiation of the BK(Ca) channels. PMID:19387586

  5. BK channels regulate spontaneous action potential rhythmicity in the suprachiasmatic nucleus.

    Directory of Open Access Journals (Sweden)

    Jack Kent

    Full Text Available BACKGROUND: Circadian ( approximately 24 hr rhythms are generated by the central pacemaker localized to the suprachiasmatic nucleus (SCN of the hypothalamus. Although the basis for intrinsic rhythmicity is generally understood to rely on transcription factors encoded by "clock genes", less is known about the daily regulation of SCN neuronal activity patterns that communicate a circadian time signal to downstream behaviors and physiological systems. Action potentials in the SCN are necessary for the circadian timing of behavior, and individual SCN neurons modulate their spontaneous firing rate (SFR over the daily cycle, suggesting that the circadian patterning of neuronal activity is necessary for normal behavioral rhythm expression. The BK K(+ channel plays an important role in suppressing spontaneous firing at night in SCN neurons. Deletion of the Kcnma1 gene, encoding the BK channel, causes degradation of circadian behavioral and physiological rhythms. METHODOLOGY/PRINCIPAL FINDINGS: To test the hypothesis that loss of robust behavioral rhythmicity in Kcnma1(-/- mice is due to the disruption of SFR rhythms in the SCN, we used multi-electrode arrays to record extracellular action potentials from acute wild-type (WT and Kcnma1(-/- slices. Patterns of activity in the SCN were tracked simultaneously for up to 3 days, and the phase, period, and synchronization of SFR rhythms were examined. Loss of BK channels increased arrhythmicity but also altered the amplitude and period of rhythmic activity. Unexpectedly, Kcnma1(-/- SCNs showed increased variability in the timing of the daily SFR peak. CONCLUSIONS/SIGNIFICANCE: These results suggest that BK channels regulate multiple aspects of the circadian patterning of neuronal activity in the SCN. In addition, these data illustrate the characteristics of a disrupted SCN rhythm downstream of clock gene-mediated timekeeping and its relationship to behavioral rhythms.

  6. Menthol increases human glioblastoma intracellular Ca2+, BK channel activity and cell migration

    Directory of Open Access Journals (Sweden)

    Bartley Jeremy W

    2009-09-01

    Full Text Available Abstract This study examined the effect of menthol, an agonist for transient receptor potential melastatin 8 (TRPM8 ion channels, to increase intracellular Ca2+ concentration, [Ca2+]i, in human glioblastoma cells (DBTRG cells, which resulted in activation of the large-conductance Ca2+-activated K+ membrane ion channels (BK channels. Voltage ramps applied over 300 ms from -100 to 100 mV resulted in membrane currents with marked inwardly- and outwardly-rectifying components. Paxilline (2 μM abolished the outwardly-rectifying current. Outwardly-rectifying on-cell patch currents were increased markedly by menthol (100 μM added to the bath. The estimated on-cell conductance of these channels was 253 pS. Kinetic analysis showed that added menthol increased channel open probability and mean open frequency after 5 min. In a similar time course menthol increased [Ca2+]i, and this increase was abolished either by added paxilline, tetraethylammonium ion or by Ca2+-free external solution. Finally, menthol stimulated the rate of DBTRG cell migration into scratch wounds made in confluent cells, and this also was inhibited by paxilline or by tetraethylammonium ion. We conclude that menthol, a TRPM8 agonist, increases DBTRG cell [Ca2+]i that in turn activates membrane BK ion channels. Inhibition of BK channels by paxilline reverses menthol-stimulated increase of [Ca2+]i and of cell migration. Thus, BK channels function to maintain elevations in [Ca2+]i needed to sustain increases in DBTRG cell migration.

  7. Viral DNA Replication-Dependent DNA Damage Response Activation during BK Polyomavirus Infection

    OpenAIRE

    Verhalen, Brandy; Justice, Joshua L.; Imperiale, Michael J; Jiang, Mengxi

    2015-01-01

    BK polyomavirus (BKPyV) reactivation is associated with severe human disease in kidney and bone marrow transplant patients. The interplay between viral and host factors that regulates the productive infection process remains poorly understood. We have previously reported that the cellular DNA damage response (DDR) is activated upon lytic BKPyV infection and that its activation is required for optimal viral replication in primary kidney epithelial cells. In this report, we set out to determine...

  8. BK/TD models for analyzing in vitro impedance data on cytotoxicity

    OpenAIRE

    Teng, Sophie; Barcellini-Couget, Sylvie; Beaudoin, Rémy; Desousa, Georges; Rahmani, Roger; Pery, Alexandre

    2015-01-01

    The ban of animal testing has enhanced the development of new in vitro technologies for cosmetics safety assessment. Impedance metrics is one such technology which enables monitoring of cell viability in real time. However, analyzing real time data requires moving from static to dynamic toxicity assessment. In the present study, we built mechanistic biokinetic/toxicodynamic (BK/TD) models to analyze the time course of cell viability in cytotoxicity assay using impedance. These models accou...

  9. Transient versus Persistent BK Viremia and Long-Term Outcomes after Kidney and Kidney–Pancreas Transplantation

    Science.gov (United States)

    Elfadawy, Nissreen; Schold, Jesse D.; Srinivas, Titte R.; Poggio, Emilio; Fatica, Richard; Avery, Robin; Mossad, Sherif B.

    2014-01-01

    Background and objectives The objective was to study the long-term impact of transient versus persistent BK viremia on kidney transplant outcomes. Design, setting, participants, & measurements In total, 609 recipients who underwent kidney transplant from 2007 to 2011 were screened at months 1–12 for the occurrence of polyomavirus BK viremia; 130 patients (21.7%) developed BK viremia during the first year post-transplant. BK viremia patients were classified according to duration of infection (more or less than 3 months), and BK viral loads (more or less than 10,000 copies/ml) were classified as transient low viremia (n=42), transient high viremia (n=18), persistent low viremia (n=23), and persistent high viremia (n=47). All patients were followed a median of 36 (3–66) months. The rates of BK polyomavirus–associated nephropathy, acute rejection, and 1-year graft function were compared with the polyomavirus BK–negative control group. Results Patient and graft survival were not significantly different among the groups. Graft function (creatinine; milligrams per deciliter) at 1 year was significantly worse in the persistent high viremia (1.75±0.6) and transient high viremia (1.85±0.7) groups compared with aviremic controls (1.47±0.4; P=0.01 and P=0.01, respectively). The incidence of BK polyomavirus–associated nephropathy was limited to the persistent high viremia group (1.3%, P<0.001). The transient high viremia (50%) and persistent high viremia (34%) groups showed significantly (P=0.01) increased incidence of acute rejection versus aviremic controls (21.5%), transient low viremia (19%), or persistent low viremia (17.3%) groups. Conclusion Low viral load BK viremia, either transient or persistent, was not associated with long-term transplant outcomes. Persistent high viremia was associated with a greater risk for BK polyomavirus–associated nephropathy and subsequent graft dysfunction. Although transient high viremia was not associated with BK

  10. A non-cardiomyocyte autonomous mechanism of cardioprotection involving the SLO1 BK channel

    Directory of Open Access Journals (Sweden)

    Andrew P. Wojtovich

    2013-03-01

    Full Text Available Opening of BK-type Ca2+ activated K+ channels protects the heart against ischemia-reperfusion (IR injury. However, the location of BK channels responsible for cardioprotection is debated. Herein we confirmed that openers of the SLO1 BK channel, NS1619 and NS11021, were protective in a mouse perfused heart model of IR injury. As anticipated, deletion of the Slo1 gene blocked this protection. However, in an isolated cardiomyocyte model of IR injury, protection by NS1619 and NS11021 was insensitive to Slo1 deletion. These data suggest that protection in intact hearts occurs by a non-cardiomyocyte autonomous, SLO1-dependent, mechanism. In this regard, an in-situ assay of intrinsic cardiac neuronal function (tachycardic response to nicotine revealed that NS1619 preserved cardiac neurons following IR injury. Furthermore, blockade of synaptic transmission by hexamethonium suppressed cardioprotection by NS1619 in intact hearts. These results suggest that opening SLO1 protects the heart during IR injury, via a mechanism that involves intrinsic cardiac neurons. Cardiac neuronal ion channels may be useful therapeutic targets for eliciting cardioprotection.

  11. BK/TD models for analyzing in vitro impedance data on cytotoxicity.

    Science.gov (United States)

    Teng, S; Barcellini-Couget, S; Beaudouin, R; Brochot, C; Desousa, G; Rahmani, R; Pery, A R R

    2015-06-01

    The ban of animal testing has enhanced the development of new in vitro technologies for cosmetics safety assessment. Impedance metrics is one such technology which enables monitoring of cell viability in real time. However, analyzing real time data requires moving from static to dynamic toxicity assessment. In the present study, we built mechanistic biokinetic/toxicodynamic (BK/TD) models to analyze the time course of cell viability in cytotoxicity assay using impedance. These models account for the fate of the tested compounds during the assay. BK/TD models were applied to analyze HepaRG cell viability, after single (48 h) and repeated (4 weeks) exposures to three hepatotoxic compounds (coumarin, isoeugenol and benzophenone-2). The BK/TD models properly fit the data used for their calibration that was obtained for single or repeated exposure. Only for one out of the three compounds, the models calibrated with a single exposure were able to predict repeated exposure data. We therefore recommend the use of long-term exposure in vitro data in order to adequately account for chronic hepatotoxic effects. The models we propose here are capable of being coupled with human biokinetic models in order to relate dose exposure and human hepatotoxicity. PMID:25827406

  12. Systematic study of spatiotemporal dynamics of intense femtosecond laser pulses in BK-7 glass

    Indian Academy of Sciences (India)

    Ram Gopal; V Deepak; S Sivaramakrishnan

    2007-04-01

    In this paper we present a systematic study of the spatial and temporal effects of intense femtosecond laser pulses in BK-7 over a broad range of input powers, 1–1000 times the critical power for self-focusing (cr) by numerically solving the nonlinear Schrödinger equation (NLS). Most numerical studies have not been extended to such high powers. A clear-cut classification of spatio-temporal dynamics up to very high powers into three regimes – the group-velocity dispersion (GVD) regime, the ionization regime and the dominant plasma regime – as done here, is a significant step towards a better understanding. Further, we examine in detail the role of GVD in channel formation by comparing BK-7 to an `artificial' medium. Our investigations bring forth the important observation that diffraction plays a minimal role in the formation of multiple cones and that plasma plays a diffraction-like role at very high powers. A detailed study of the spatio-temporal dynamics in any condensed medium over this range of powers has not been reported hitherto, to the best of our knowledge. We also suggest appropriate operational powers for various applications employing BK-7 on the basis of our results.

  13. Selective inhibition of phosphodiesterase 1 relaxes urinary bladder smooth muscle: role for ryanodine receptor-mediated BK channel activation

    OpenAIRE

    Xin, Wenkuan; Soder, Rupal P; Cheng, Qiuping; Eric S. Rovner; Petkov, Georgi V.

    2012-01-01

    The large conductance voltage- and Ca2+-activated K+ (BK) channel is a major regulator of detrusor smooth muscle (DSM) excitability and contractility. Recently, we showed that nonselective phosphodiesterase (PDE) inhibition reduces guinea pig DSM excitability and contractility by increasing BK channel activity. Here, we investigated how DSM excitability and contractility changes upon selective inhibition of PDE type 1 (PDE1) and the underlying cellular mechanism involving ryanodine receptors ...

  14. S-acylation dependent post-translational cross-talk regulates large conductance calcium- and voltage- activated potassium (BK channels

    Directory of Open Access Journals (Sweden)

    MichaelJShipston

    2014-08-01

    Full Text Available Mechanisms that control surface expression and/or activity of large conductance calcium-activated potassium (BK channels are important determinants of their (pathophysiological function. Indeed, BK channel dysfunction is associated with major human disorders ranging from epilepsy to hypertension and obesity. S-acylation (S-palmitoylation represents a major reversible, post-translational modification controlling the properties and function of many proteins including ion channels. Recent evidence reveals that both pore-forming and regulatory subunits of BK channels are S-acylated and control channel trafficking and regulation by AGC-family protein kinases. The pore-forming α-subunit is S-acylated at two distinct sites within the N- and C-terminus, each site being regulated by different palmitoyl acyl transferases (zDHHCs and acyl thioesterases. (APTs. S-acylation of the N-terminus controls channel trafficking and surface expression whereas S-acylation of the C-terminal domain determines regulation of channel activity by AGC-family protein kinases. S-acylation of the regulatory β4-subunit controls ER exit and surface expression of BK channels but does not affect ion channel kinetics at the plasma membrane. Furthermore, a significant number of previously identified BK-channel interacting proteins have been shown, or are predicted to be, S-acylated. Thus, the BK channel multi-molecular signalling complex may be dynamically regulated by this fundamental post-translational modification and thus S-acylation likely represents an important determinant of BK channel physiology in health and disease.

  15. Bk and Cf chromatographic separation and ²⁴⁹Bk/²⁴⁸Cm and ²⁴⁹Cf/²⁴⁸Cm elemental ratios determination by inductively coupled plasma quadrupole mass spectrometry.

    Science.gov (United States)

    Gourgiotis, A; Isnard, H; Nonell, A; Aubert, M; Stadelmann, G; Dupont, E; AlMahamid, I; Tiang, G; Rao, L; Lukens, W; Cassette, P; Panebianco, S; Letourneau, A; Chartier, F

    2013-03-15

    The French Atomic Energy Commission has carried out several experiments for the study of minor-actinide transmutation processes in high intensity thermal neutron flux. In this context a Cm sample enriched in (248)Cm (∼97%) was irradiated in a thermal neutron flux at the High Flux Reactor (HFR) of the Laue-Langevin Institute (ILL). The precise and accurate determination of Cf isotope ratios and of (249)Bk/(248)Cm and (249)Cf/(248)Cm elemental ratios in the (248)Cm irradiated sample is crucial for the calculation of actinide neutron capture cross-sections. This work describes an analytical procedure for the separation and the isotope ratio measurement of Bk and Cf in the irradiated sample. The Bk and Cf separation is based on a lanthanides separation protocol previously developed by the laboratory. Well-defined retention times for Bk and Cf were obtained by coupling the Ionic Chromatography (IC) with an ICP-QMS. All conditions of element separation by IC and the different steps of the analytical protocol in order to obtain the isotopic and elemental ratios are presented. Relative uncertainties of Cf isotopic ratios range from 0.3% to 0.5% and the uncertainty of the (249)Bk/(248)Cm and (249)Cf/(248)Cm elemental ratios are respectively 6.1% and 3.2%. This level of uncertainty for both isotopic and elemental ratios is in perfect agreement with the requirement for transmutation studies. PMID:23598093

  16. Ca2+- and voltage-gated potassium (BK) channel activators in the 5β-cholanic acid-3α-ol analogue series with modifications in lateral chain

    OpenAIRE

    Bukiya, Anna N.; Patil, Shivaputra; Li, Wei; Miller, Duane; Dopico, Alex M.

    2012-01-01

    Large conductance, calcium- and voltage-gated potassium (BK) channels regulate various physiological processes and represent an attractive target for drug discovery. Numerous BK channel activators are available. However, these agents usually interact with the ubiquitously distributed channel-forming subunit and thus cannot selectively target a particular tissue. Here, we performed structure-activity relationship study of lithocholic acid (LCA), a cholane that activates BK channels via the acc...

  17. Intracellular segment between transmembrane helices S0 and S1 of BK channel α subunit contains two amphipathic helices connected by a flexible loop

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Pan [Hefei National Laboratory of Microscale Physical Sciences, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230027 (China); High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui, 230031 (China); Li, Dong; Lai, Chaohua [Hefei National Laboratory of Microscale Physical Sciences, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230027 (China); Zhang, Longhua, E-mail: zlhustc@ustc.edu.cn [Hefei National Laboratory of Microscale Physical Sciences, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230027 (China); Tian, Changlin, E-mail: cltian@ustc.edu.cn [Hefei National Laboratory of Microscale Physical Sciences, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230027 (China); High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui, 230031 (China)

    2013-08-02

    Highlights: •The loop between S0 and S1 of BK channel was overexpressed and purified in DPC. •NMR studies indicated BK-IS1 contained two helices connected by a flexible loop. •Mg{sup 2+} titration of BK-IS1 indicated two possible binding sites of divalent ions. -- Abstract: The BK channel, a tetrameric potassium channel with very high conductance, has a central role in numerous physiological functions. The BK channel can be activated by intracellular Ca{sup 2+} and Mg{sup 2+}, as well as by membrane depolarization. Unlike other tetrameric potassium channels, the BK channel has seven transmembrane helices (S0–S6) including an extra helix S0. The intracellular segment between S0 and S1 (BK-IS1) is essential to BK channel functions and Asp99 in BK-IS1 is reported to be responsible for Mg{sup 2+} coordination. In this study, BK-IS1 (44–113) was over-expressed using a bacterial system and purified in the presence of detergent micelles for multidimensional heteronuclear nuclear magnetic resonance (NMR) structural studies. Backbone resonance assignment and secondary structure analysis showed that BK-IS1 contains two amphipathic helices connected by a 36-residue loop. Amide {sup 1}H–{sup 15}N heteronuclear NOE analysis indicated that the loop is very flexible, while the two amphipathic helices are possibly stabilized through interaction with the membrane. A solution NMR-based titration assay of BK-IS1 was performed with various concentrations of Mg{sup 2+}. Two residues (Thr45 and Leu46) with chemical shift changes were observed but no, or very minor, chemical shift difference was observed for Asp99, indicating a possible site for binding divalent ions or other modulation partners.

  18. Viabilitas dan Kemampuan Bakteri Kitinolitik Bacillus sp. BK17 dalam Formulasi Tablet untuk Mengurangi Layu Fusarium pada Benih Cabai Merah (Capsicum annuum L.)

    OpenAIRE

    Sitohang, Arance Yoane Itoi Imaulina

    2015-01-01

    Chitinolytic bacteria Bacillus sp. BK17 has been known to inhibit the growth of Fusarium oxysporum on chili seeds. Bacterial cell viability is an important factor in using the cell for biological control. This study was aimed to evaluate viability of chitinolytic bacteria Bacillus sp. BK17 and its potential in tablet formulation as a biological control againstF. oxysporum. Viability of Bacillus sp. BK17 cell was reduced in 40 days of storage. Bacillus sp. BK17 in tablet formulation was able t...

  19. Erbium-doped ion-exchanged waveguide lasers in BK-7 glass

    OpenAIRE

    Feuchter, T.; Mwarania, E.K.; Wang, J.; Reekie, L.; J. S. Wilkinson

    1992-01-01

    Ion exchange in glass is a simple, flexible, technique to realize optical fiber compatible planar waveguide devices. Recently, neodymium-doped waveguide lasers operating at 1060 and 1300 nm have been demonstrated in this technology. Lasers operating at 1540 nm are desirable for telecommunication applications and we report here, for the first time, ion-exchanged waveguide lasers in erbium-doped glass emitting at this wavelength. Lasers in BK-7 glass doped with 0.5 wt% Er2O3 and pumped at 980 n...

  20. Low-loss waveguides fabricated in BK7 glass by high repetition rate femtosecond fiber laser

    International Nuclear Information System (INIS)

    For the first time femtosecond-laser writing has inscribed low-loss optical waveguides in Schott BK7 glass, a commercially important type of borosilicate widely used in optical applications. The use of a variable repetition rate laser enabled the identification of a narrow processing window at 1 MHz repetition rate with optimal waveguides exhibiting propagation losses of 0.3 dB/cm and efficient mode matching to standard optical fibers at a 1550 nm wavelength. The waveguides were characterized by complementary phase contrast and optical transmission microscopy, identifying a micrometer-sized guiding region within a larger complex structure of both positive and negative refractive index variations

  1. Preliminary study on rotary ultrasonic machining of Bk-7 optical glass rod

    International Nuclear Information System (INIS)

    This paper presents an experimental observation on rotary ultrasonic machining (RUM) of BK7 optical glass rod. BK7 is a common technical optical glass for high quality optical components due to its high linear optical transmission in the visible range and is chemically stable. RUM is a hybrid machining process that combines the material removal mechanisms of diamond grinding and ultrasonic machining (USM) and it is non-thermal, non-chemical, creates no change in the microstructure, chemical or physical properties of the work piece. In the RUM, a controlled static load is applied to the rotating core drill with metal bonded diamond abrasive and is ultrasonically vibrated in the axial direction. A water-soluble coolant was used to cool the tool and sample during machining processes. By using DOE (Design of Experiment) approach, the effect of spindle speed and feed rate to the ultrasonic machinability had been developed. The main effects and two-factor interactions of process parameters (spindle speed) and feed rate) on output variables (MRR, surface roughness, opaqueness, chipping thickness and chipping size) are studied. (author)

  2. BK Lyncis: The Oldest Old Nova?... And a Bellwether for Cataclysmic-Variable Evolution

    CERN Document Server

    Patterson, Joseph; Kemp, Jonathan; de Miguel, Enrique; Krajci, Thomas; Foote, Jerry; Hambsch, Franz-Josef; Campbell, Tut; Roberts, George; Cejudo, David; Dvorak, Shawn; Vanmunster, Tonny; Koff, Robert; Skillman, David; Harvey, David; Martin, Brian; Rock, John; Boyd, David; Oksanen, Arto; Morelle, Etienne; Ulowetz, Joseph; Kroes, Anthony; Sabo, Richard; Jensen, Lasse

    2012-01-01

    We summarize the results of a 20-year campaign to study the light curves of BK Lyncis, a nova-like star strangely located below the 2-3 hour orbital period gap in the family of cataclysmic variables. Two apparent "superhumps" dominate the nightly light curves - with periods 4.6% longer, and 3.0% shorter, than P_orb. The first appears to be associated with the star's brighter states (V~14), while the second appears to be present throughout and becomes very dominant in the low state (V~15.7). Starting in the year 2005, the star's light curve became indistinguishable from that of a dwarf nova - in particular, that of the ER UMa subclass. Reviewing all the star's oddities, we speculate: (a) BK Lyn is the remnant of the probable nova on 30 December 101, and (b) it has been fading ever since, but has taken ~2000 years for the accretion rate to drop sufficiently to permit dwarf-nova eruptions. If such behavior is common, it can explain other puzzles of CV evolution. One: why the ER UMa class even exists (because all...

  3. On the Operator ⨁Bk Related to Bessel Heat Equation

    Directory of Open Access Journals (Sweden)

    Wanchak Satsanit

    2010-01-01

    Full Text Available We study the equation (∂/∂tu(x,t=c2⊕Bku(x,t with the initial condition u(x,0=f(x for x∈Rn+. The operator ⊕Bk is the operator iterated k-times and is defined by ⊕Bk=((∑i=1pBxi4-(∑j=p+1p+qBxi4k, where p+q=n is the dimension of the Rn+, Bxi=∂2/∂xi2+(2vi/xi(∂/∂xi, 2vi=2αi+1, αi>-1/2, i=1,2,3,…,n, and k is a nonnegative integer, u(x,t is an unknown function for (x,t=(x1,x2,…,xn,t∈Rn+×(0,∞, f(x is a given generalized function, and c is a positive constant. We obtain the solution of such equation, which is related to the spectrum and the kernel, which is so called Bessel heat kernel. Moreover, such Bessel heat kernel has interesting properties and also related to the kernel of an extension of the heat equation.

  4. Diffuse gastrointestinal bleeding and BK polyomavirus replication in a pediatric allogeneic haematopoietic stem cell transplant patient.

    Science.gov (United States)

    Koskenvuo, M; Lautenschlager, I; Kardas, P; Auvinen, E; Mannonen, L; Huttunen, P; Taskinen, M; Vettenranta, K; Hirsch, H H

    2015-01-01

    Patients undergoing haematopoietic stem cell transplantation (HSCT) are at high risk of severe gastrointestinal bleeding caused by infections, graft versus host disease, and disturbances in haemostasis. BK polyomavirus (BKPyV) is known to cause hemorrhagic cystitis, but there is also evidence of BKV shedding in stool and its association with gastrointestinal disease. We report putative association of BKPyV replication with high plasma viral loads in a pediatric HSCT patient developing hemorrhagic cystitis and severe gastrointestinal bleeding necessitating intensive care. The observation was based on chart review and analysis of BKPyV DNA loads in plasma and urine as well as retrospective BKPyV-specific IgM and IgG measurements in weekly samples until three months post-transplant. The gastrointestinal bleeding was observed after a >100-fold increase in the plasma BKPyV loads and the start of hemorrhagic cystitis. The BKPyV-specific antibody response indicated past infection prior to transplantation, but increasing IgG titers were seen following BKPyV replication. The gastrointestinal biopsies were taken at a late stage of the episode and were no longer informative of BK polyomavirus involvement. In conclusion, gastrointestinal complications with bleeding are a significant problem after allogeneic HSCT to which viral infections including BKPyV may contribute. PMID:25542476

  5. A new precise mass for the progenitor of the Type IIP SN 2008bk

    CERN Document Server

    Maund, J R; Ramirez-Ruiz, E; Eldridge, J J

    2013-01-01

    The progenitor of the Type IIP SN 2008bk was discovered in pre-explosion g'r'i'IYJHKs images, acquired with European Southern Observatory Very Large Telescope FORS, HAWK-I and ISAAC instruments and the Gemini GMOS-S instrument. The wealth of pre-explosion observations makes the progenitor of this SN one of the best studied, since the detection of the progenitor of SN1987A. Previous analyses of the properties of the progenitor were hampered by the limited quality of the photometric calibration of the pre-explosion images and the crowded nature of the field containing the SN. We present new late-time observations of the site of SN2008bk acquired with identical instrument and filter configurations as the pre-explosion observations, and confirm that the previously identified red supergiant star was the progenitor of this SN and has now disappeared. Image subtraction techniques were used to conduct precise photometry of the now missing progenitor, independently of blending from any nearby stars. The nature of the ...

  6. The role of N-terminal and C-terminal Arg residues from BK on interaction with kinin B2 receptor.

    Science.gov (United States)

    Filippelli-Silva, Rafael; Martin, Renan P; Rodrigues, Eliete S; Nakaie, Clovis R; Oliveira, Laerte; Pesquero, João B; Shimuta, Suma I

    2016-04-01

    Bradykinin (BK) is a nonapeptide important for several physiological processes such as vasodilatation, increase in vascular permeability and release of inflammatory mediators. BK performs its actions by coupling to and activating the B2 receptor, a family A G-protein coupled receptor. Using a strategy which allows systematical monitoring of BK R1 and R9 residues and B2 receptor acidic residues Glu5.35(226) and Asp6.58(298), our study aims at clarifying the BK interaction profile with the B2 receptor [receptor residue numbers are normalized according to Ballesteros and Weinstein, Methods Neurosci. 25 (1995), pp. 366-428) followed by receptor sequence numbering in brackets]. N- and C-terminal analogs of BK (-A1, -G1, -K1, -E1 and BK-A9) were tested against wild type B2, Glu5.35(226)Ala and Asp6.58(298)Ala B2 mutant receptors for their affinity and capability to elicit responses by mechanical recordings of isolated mice stomach fundus, measuring intracellular calcium mobilization, and competitive fluorimetric binding assays. BK showed 2- and 15-fold decreased potency for Glu5.35(226) and Asp6.58(298) B2 mutant receptors, respectively. In B2-Glu5.35(226)Ala BK analogs showed milder reduction in evaluated parameters. On the other hand, in the B2-Asp6.58(298)Ala mutant, no N-terminal analog was able to elicit any response. However, the BK-A9 analog presented higher affinity parameters than BK in the latter mutant. These findings provide enough support for defining a novel interaction role of BK-R9 and Asp6.58(298) receptor residues. PMID:26584354

  7. PENGEMBANGAN INSTRUMEN ASESMEN KEBUTUHAN PERKEMBANGAN UNTUK PENYUSUNAN KURIKULUM DAN EVALUASI PROGRAM BK

    Directory of Open Access Journals (Sweden)

    Gendon Barus

    2013-01-01

    Full Text Available Penelitian pengembangan ini bertujuan menghasilkan instrumen asesmen kebutuhan peserta didik, disebut Invantori Kebutuhan Perkembangan Murid (IKPM. Penelitian mengikuti model Plomp (1999 dengan lima fase. Reliabilitas instrumen diestimasi dengan teknik Alpha Cronbach, validitas isi diperiksa oleh pakar dan telaah praktisi melalui FGD. Validitas empirik dan kecocokan model pengukuran dibuktikan dengan analisis faktor konfirmatori (CFA dengan program Lisrel 8.30. Telaah praktisi melibatkan 60 orang guru kelas V dan VI SD dalam dua tahap FGD, sedangkan uji coba empirik dan implementasi melibatkan murid kelas V dan VI. Hasil penelitian pengembang-an ini adalah: 1 IKPM dapat digunakan untuk menghimpun data kebutuhan perkembangan sebagai dasar penyusunan kurikulum bimbingan dan melaksanakan evaluasi program, bimbingan dan alat ukur evaluasi program bimbingan klasikal di sekolah dasar dan 2 teridentifikasi butir-butir kebutuhan per-kembangan murid yang intens dan sangat intens untuk dipenuhi melalui layanan bimbingan klasikal. Kata kunci: instrumen asesmen kebutuhan, kurikulum bimbingan, instrument evaluasi program BK ______________________________________________________________ DEVELOPMENT OF DEVELOPMENTAL NEEDS ASSESSMENT INSTRUMENT FOR CURRICULUM ARRANGEMENT AND EVALUATION OF BK PROGRAM Abstract The goal of this research is to produce a developmental needs assessment instrument, called Student’s Developmental Needs Inventory, which can be use to reveal the needs of students in elementary school. The research method follows the model of Research and Development (R & D by Plomp (1999 with five phases. The instrument which is developed in this study guidance and counseling (Bimbingan Konseling, BK in elementary school. Instrument reliability is estimated using by Alpha Cronbach technique, it content validity is checked by experts judgment and practitioner’s assessment with FGD technique. Furthermore, empirical validity and the goodness of fit

  8. VIRAL INFECTIONS IN BONE MARROW TRANSPLANTS: IS JC VIRUS INVOLVED?

    OpenAIRE

    Mischitelli, Monica; Fioriti, Daniela; Anzivino, Elena; Bellizzi, Anna; Barucca, Valentina; BOLDORINI, RENZO; Miglio, Umberto; Sica, Simona; Sorà, Federica; De Matteis, Silvia; Chiarini, Fernanda; Pietropaolo, Valeria

    2009-01-01

    Abstract Haemorrhagic cystitis is characterized by haematuria due to inflammation of the bladder. In bone marrow transplants, this disease is linked to the infection by human polyomavirus BK, whereas the role of the human polyomavirus JC is unclear. The transcriptional control regions of both viruses contain important cellular transcription factor binding sites that undergo rearrangement process generating suitable variants that could be more active for viral replication and for th...

  9. Late post transplant HIV infection with BK viremia and allograft tuberculosis in a renal transplant recipient with Kaposi sarcoma

    OpenAIRE

    Viswanathan, V.; Kandasamy, V.; Reddy, Y. N.; Kurien, A.; Mathew, M.; Abraham, G

    2012-01-01

    In this report, we discuss a case of a 51-year-old African renal transplant who presented with metastatic Kaposi sarcoma 1 year after transplant. The Kaposi sarcoma was treated with a switch of immunosuppressants and chemotherapy. Six years after transplant, he presented with chronic allograft nephropathy, allograft tuberculosis, BK viremia, and was diagnosed to have contracted HIV infection.

  10. Draft Genome Sequence of an Invasive Multidrug-Resistant Strain, Pseudomonas aeruginosa BK1, Isolated from a Keratitis Patient

    KAUST Repository

    Jeganathan, Lakshmi Priya

    2014-03-27

    Pseudomonas aeruginosa infections are difficult to treat due to the presence of a multitude of virulence factors and antibiotic resistance. Here, we report the draft genome sequence of P. aeruginosa BK1, an invasive and multidrug-resistant strain, isolated from a bacterial keratitis patient in southern India.

  11. Mathematical modeling of surface roughness in magnetic abrasive finishing of BK7 optical glass.

    Science.gov (United States)

    Pashmforoush, Farzad; Rahimi, Abdolreza; Kazemi, Mehdi

    2015-10-01

    Magnetic abrasive finishing (MAF) is one of the advanced machining processes efficiently used to finish hard-to-machine materials. Simulation and modeling of the process is of particular importance to understand the mechanics of material removal and consequently achieve a high-quality surface with a minimum of surface defects. Hence, in this paper, we performed a numerical-experimental study to mathematically model the surface roughness during the MAF of BK7 optical glass. For this purpose, the initial roughness profile was estimated using fast Fourier transform (FFT) and a Gaussian filter. We obtained the final surface profile based on the material removal mechanisms and the corresponding chipping depth values evaluated by finite element analysis. We then validated experimentally the simulation results in terms of the arithmetic average surface roughness (R(a ). The comparison between the obtained results demonstrates that the theoretical and experimental findings are in good agreement when predicting the parameters' effect on surface roughness behavior. PMID:26479596

  12. Simultaneous BK Polyomavirus (BKPyV)-associated nephropathy and hemorrhagic cystitis after living donor kidney transplantation.

    Science.gov (United States)

    Helanterä, Ilkka; Hirsch, Hans H; Wernli, Marion; Ortiz, Fernanda; Lempinen, Marko; Räisänen-Sokolowski, Anne; Auvinen, Eeva; Mannonen, Laura; Lautenschlager, Irmeli

    2016-03-01

    BK polyomavirus (BKPyV) commonly reactivates after kidney transplantation, and can cause polyomavirus-associated nephropathy (PyVAN), whereas after allogeneic stem cell transplantation the most frequent manifestation of BKPyV is polyomavirus-associated hemorrhagic cystitis (PyVHC). Despite high-level BKPyV replication in both, the pathogenesis and manifestation of both BKPyV entities appears to differ substantially. We describe an unusual case of simultaneous PyVAN and PyVHC presenting with acute symptoms in a BKPyV-IgG positive recipient eight months after kidney transplantation from a haploidentical living donor, who was BKPyV-IgG negative. Symptoms of cystitis and viremia subsided rapidly after reduction of immunosuppression. PMID:26771744

  13. Oxytocin hyperpolarizes cultured duodenum myenteric intrinsic primary afferent neurons by opening BK(Ca) channels through IP₃ pathway.

    Science.gov (United States)

    Che, Tongtong; Sun, Hui; Li, Jingxin; Yu, Xiao; Zhu, Dexiao; Xue, Bing; Liu, Kejing; Zhang, Min; Kunze, Wolfgang; Liu, Chuanyong

    2012-05-01

    Oxytocin (OT) is clinically important in gut motility and constitutively reduces duodenum contractility. Intrinsic primary afferent neurons (IPANs), whose physiological classification is as AH cells, are the 1st neurons of the peristaltic reflex pathway. We set out to investigate if this inhibitory effect is mediated by IPANs and to identify the ion channel(s) and intracellular signal transduction pathway that are involved in this effect. Myenteric neurons were isolated from the longitudinal muscle myenteric plexus (LMMP) preparation of rat duodenum and cultured for 16-24 h before electrophysiological recording in whole cell mode and AH cells identified by their electrophysiological characteristics. The cytoplasmic Ca²⁺ concentration ([Ca²⁺](i) ) of isolated neurons was measured using calcium imaging. The concentration of IP(3) in the LMMP and the OT secreted from the LMMP were measured using ELISA. The oxytocin receptor (OTR) and large-conductance calcium-activated potassium (BK(Ca)) channels, as well as the expression of OT and the IPAN marker calbindin 28 K, on the myenteric plexus neurons were localized using double-immunostaining techniques. We found that administration of OT (10⁻⁷ to 10⁻⁵ M) dose dependently hyperpolarized the resting membrane potential and increased the total outward current. The OTR antagonist atosiban or the BK(Ca) channel blocker iberiotoxin (IbTX) blocked the effects of OT suggesting that the increased outward current resulted from BK(Ca) channel opening. OTR and the BK(Ca) α subunit were co-expressed on a subset of myenteric neurons at the LMMP. NS1619 (10⁻⁵ M, a BK(Ca) channel activator) increased the outward current similar to the effect of OT. OT administration also increased [Ca²⁺](i) and the OT-evoked outward current was significantly attenuated by thapsigargin (10⁻⁶ M) or CdCl₂. The effect of OT on the BK(Ca) current was also blocked by pre-treatment with the IP₃ receptor antagonist 2-APB (10⁻⁴ M

  14. Hydrogen Peroxide Stimulates the Ca2+-activated Big-Conductance K Channels (BK) Through cGMP Signaling Pathway in Cultured Human Endothelial Cells

    OpenAIRE

    Dong, De-Li; Yue, Peng; Yang, Bao-Feng; Wang, Wen-Hui

    2008-01-01

    We used the whole cell patch-clamp technique to examine the effect of hydrogen peroxide (H2O2) on the Ca2+-activated BK channels in human endothelial cells. We confirmed the previous finding that a 200 pS BK channel activity was detected when the cell membrane potential was clamped at 50 mV. Application of H2O2 or adding glucose oxidase (GO) stimulated BK channels. The stimulatory effect of H2O2 and GO was absent in cells treated with ebselen, a scavenger of reactive oxygen species (ROS). To ...

  15. Heartland Virus

    Science.gov (United States)

    ... Vector-Borne Diseases (DVBD) NCEZID Share Compartir Heartland virus On this Page What is Heartland virus? How ... Do I Need to Know? What is Heartland virus? Heartland virus belongs to a family of viruses ...

  16. Probing new physics through B->K l+ l- decays in R-parity violating minimal supersymmetric standard model

    CERN Document Server

    Mir, Azeem

    2009-01-01

    We study the decay rate of process B->K l+ l- (l=e,mu) and some of its other related observables, like forward backward asymmetry (A_{FB}), polarization asymmetry (PA) and CP-asymmetry (A_{CP}) in R-parity violating (R_{p}) Minimal Supersymmetric Standard Model (MSSM). The analysis shows that R_{p}Yukawa coupling products contribute significantly to the branching fraction of B->K l+ l- within 1 sigma and 2 sigma. Study shows that PA and A_{FB} are sensitive enough to R_{p}Yukawa coupling products and turn out to be good predictions for measurement in future experiments.The CP-asymmetry calculated in this framework agrees well with the recently reported value(i.e. 7%).

  17. Production and investigation of thin films of metal actinides (Pu, Am, Cm, Bk, Cf)

    Science.gov (United States)

    Radchenko, V. M.; Ryabinin, M. A.; Stupin, V. A.

    2010-03-01

    Under limited availability of transplutonium metals some special techniques and methods of their production have been developed that combine the process of metal reduction from a chemical compound and preparation of a sample for examination. In this situation the evaporation and condensation of metal onto a substrate becomes the only possible technology. Thin film samples of metallic 244Cm, 248Cm and 249Bk were produced by thermal reduction of oxides with thorium followed by deposition of the metals in the form of thin layers on tantalum substrates. For the production of 249Cf metal in the form of a thin layer the method of thermal reduction of oxide with lanthanum was used. 238Pu and 239Pu samples in the form of films were prepared by direct high temperature evaporation and condensation of the metal onto a substrate. For the production of 241Am films a gram sample of plutonium-241 metal was used containing about 18 % of americium at the time of production. Thermal decomposition of Pt5Am intermetallics in vacuum was used to produce americium metal with about 80% yield. Resistivity of the metallic 249Cf film samples was found to decrease exponentially with increasing temperature. The 249Cf metal demonstrated a tendency to form preferably a DHCP structure with the sample mass increasing. An effect of high specific activity on the crystal structure of 238Pu nuclide thin layers was studied either.

  18. Production and investigation of thin films of metal actinides (Pu, Am, Cm, Bk, Cf)

    International Nuclear Information System (INIS)

    Under limited availability of transplutonium metals some special techniques and methods of their production have been developed that combine the process of metal reduction from a chemical compound and preparation of a sample for examination. In this situation the evaporation and condensation of metal onto a substrate becomes the only possible technology. Thin film samples of metallic 244Cm, 248Cm and 249Bk were produced by thermal reduction of oxides with thorium followed by deposition of the metals in the form of thin layers on tantalum substrates. For the production of 249Cf metal in the form of a thin layer the method of thermal reduction of oxide with lanthanum was used. 238Pu and 239Pu samples in the form of films were prepared by direct high temperature evaporation and condensation of the metal onto a substrate. For the production of 241Am films a gram sample of plutonium-241 metal was used containing about 18 % of americium at the time of production. Thermal decomposition of Pt5Am intermetallics in vacuum was used to produce americium metal with about 80% yield. Resistivity of the metallic 249Cf film samples was found to decrease exponentially with increasing temperature. The 249Cf metal demonstrated a tendency to form preferably a DHCP structure with the sample mass increasing. An effect of high specific activity on the crystal structure of 238Pu nuclide thin layers was studied either.

  19. The dystrophin complex controls bk channel localization and muscle activity in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Hongkyun Kim

    2009-12-01

    Full Text Available Genetic defects in the dystrophin-associated protein complex (DAPC are responsible for a variety of pathological conditions including muscular dystrophy, cardiomyopathy, and vasospasm. Conserved DAPC components from humans to Caenorhabditis elegans suggest a similar molecular function. C. elegans DAPC mutants exhibit a unique locomotory deficit resulting from prolonged muscle excitation and contraction. Here we show that the C. elegans DAPC is essential for proper localization of SLO-1, the large conductance, voltage-, and calcium-dependent potassium (BK channel, which conducts a major outward rectifying current in muscle under the normal physiological condition. Through analysis of mutants with the same phenotype as the DAPC mutants, we identified the novel islo-1 gene that encodes a protein with two predicted transmembrane domains. We demonstrate that ISLO-1 acts as a novel adapter molecule that links the DAPC to SLO-1 in muscle. We show that a defect in either the DAPC or ISLO-1 disrupts normal SLO-1 localization in muscle. Consistent with observations that SLO-1 requires a high calcium concentration for full activation, we find that SLO-1 is localized near L-type calcium channels in muscle, thereby providing a mechanism coupling calcium influx with the outward rectifying current. Our results indicate that the DAPC modulates muscle excitability by localizing the SLO-1 channel to calcium-rich regions of C. elegans muscle.

  20. P-waves imaging of the FRI and BK zones at the Grimsel Rock Laboratory

    International Nuclear Information System (INIS)

    This report is one of a series documenting the results of the Nagra-DOE Cooperative (NDC-I) research program in which the cooperating scientists explore the geological, geophysical, hydrological, geochemical, and structural effects anticipated from the use of a rock mass as a geological repository for nuclear waste. Tomographic imaging studies using a high frequency (10 Khz.) piezoelectric source and a three component receiver were carried out in two different regions of the underground Nagra Grimsel test facility in Switzerland. Both sites were in fractured granite, one being in a strongly foliated granite (FRI site), and the other being in a relatively homogeneous granite (BK zone). The object of the work was to determine if the seismic techniques could be useful in imaging the fracture zones and provide information on the hydrologic conditions. Both amplitude and velocity tomograms were obtained from the Data. The results indicate that the fracture zones strongly influenced the seismic wave propagation, thus imaging the fracture zones that were hydrologically important. 11 refs., 24 figs

  1. Human BK Polyomavirus—The Potential for Head and Neck Malignancy and Disease

    Directory of Open Access Journals (Sweden)

    Raquel Burger-Calderon

    2015-07-01

    Full Text Available Members of the human Polyomaviridae family are ubiquitous and pathogenic among immune-compromised individuals. While only Merkel cell polyomavirus (MCPyV has conclusively been linked to human cancer, all members of the polyomavirus (PyV family encode the oncoprotein T antigen and may be potentially carcinogenic. Studies focusing on PyV pathogenesis in humans have become more abundant as the number of PyV family members and the list of associated diseases has expanded. BK polyomavirus (BKPyV in particular has emerged as a new opportunistic pathogen among HIV positive individuals, carrying harmful implications. Increasing evidence links BKPyV to HIV-associated salivary gland disease (HIVSGD. HIVSGD is associated with elevated risk of lymphoma formation and its prevalence has increased among HIV/AIDS patients. Determining the relationship between BKPyV, disease and tumorigenesis among immunosuppressed individuals is necessary and will allow for expanding effective anti-viral treatment and prevention options in the future.

  2. UV protection filters by dielectric multilayer thin films on Glass BK-7 and Infrasil 301

    Science.gov (United States)

    Abdel-Aziz, M. M.; Azim, Osama A.; Abdel-Wahab, L. A.; Seddik, Mohamed M.

    2006-10-01

    The increasing use of Ultraviolet (UV) light in medicine, industrial environments, for cosmetic use, and even in consumer products necessitates that greater attention be paid to the potential hazards of this type of electromagnetic radiation. To avoid any adverse effects of exposure to this type of radiation, four suitable protection filters were produced to block three UV bands (UVA, UVB, and UVC). The design structure of the required dielectric multilayer filters was done by optical thin film technology using the absorbing property of UV radiation for the substrates and dielectric materials. The computer analyses of the multilayer filter formulas were prepared using Macleod Software for the production processes. The deposition technique was achieved on optical substrates (Glass BK-7 and Infrasil 301) by dielectric material combinations including Titanium dioxide (Ti 2O 3), Hafnium dioxide (HfO 2), and Lima (mixture of oxides SiO 2/Al 2O 3); deposition being achieved using an electron beam gun. The output results of the theoretical and experimental transmittance values for spectral band from 200 nm to 800 nm were discussed in four processes. To analyze the suitability for use in 'real world' applications, the test pieces were subjected to the durability tests (adhesion, abrasion resistance, and humidity) according to Military Standard MIL-C-675C and MIL-C-48497A.

  3. UV protection filters by dielectric multilayer thin films on Glass BK-7 and Infrasil 301

    International Nuclear Information System (INIS)

    The increasing use of Ultraviolet (UV) light in medicine, industrial environments, for cosmetic use, and even in consumer products necessitates that greater attention be paid to the potential hazards of this type of electromagnetic radiation. To avoid any adverse effects of exposure to this type of radiation, four suitable protection filters were produced to block three UV bands (UVA, UVB, and UVC). The design structure of the required dielectric multilayer filters was done by optical thin film technology using the absorbing property of UV radiation for the substrates and dielectric materials. The computer analyses of the multilayer filter formulas were prepared using Macleod Software for the production processes. The deposition technique was achieved on optical substrates (Glass BK-7 and Infrasil 301) by dielectric material combinations including Titanium dioxide (Ti2O3), Hafnium dioxide (HfO2), and Lima (mixture of oxides SiO2/Al2O3); deposition being achieved using an electron beam gun. The output results of the theoretical and experimental transmittance values for spectral band from 200 nm to 800 nm were discussed in four processes. To analyze the suitability for use in 'real world' applications, the test pieces were subjected to the durability tests (adhesion, abrasion resistance, and humidity) according to Military Standard MIL-C-675C and MIL-C-48497A

  4. Continuum Limit of $B_K$ from 2+1 Flavor Domain Wall QCD

    CERN Document Server

    Aoki, Y; Blum, T; Boyle, P A; Brömmel, D; Christ, N H; Dawson, C; Izubuchi, T; Jung, C; Kelly, C; Kenway, R D; Lightman, M; Mawhinney, R D; Ohta, Shigemi; Sachrajda, C T; Scholz, E E; Soni, A; Sturm, C; Wennekers, J; Zhou, R

    2010-01-01

    We determine the neutral kaon mixing matrix element $B_K$ in the continuum limit with 2+1 flavors of domain wall fermions, using the Iwasaki gauge action at two different lattice spacings. These lattice fermions have near exact chiral symmetry and therefore avoid artificial lattice operator mixing. We introduce a significant improvement to the conventional NPR method in which the bare matrix elements are renormalized non-perturbatively in the RI-MOM scheme and are then converted into the MSbar scheme using continuum perturbation theory. In addition to RI-MOM, we introduce and implement four non-exceptional intermediate momentum schemes that suppress infrared non-perturbative uncertainties in the renormalization procedure. We compute the conversion factors relating the matrix elements in this family of RI-SMOM schemes and MSbar at one-loop order. Comparison of the results obtained using these different intermediate schemes allows for a more reliable estimate of the unknown higher-order contributions and hence ...

  5. UV protection filters by dielectric multilayer thin films on Glass BK-7 and Infrasil 301

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Aziz, M.M. [Physics Department, Faculty of Education, Ain Shams University, Cairo 11566 (Egypt)]. E-mail: melaziz@link.net; Azim, Osama A. [Vacuum Coating Manager, Arab International Optronics Co., El-salam City, Cairo 11566 (Egypt); Abdel-Wahab, L.A. [Head of Thermal Analysis Lab, National Center for Radiation Research and Technology, Cairo 11566 (Egypt); Seddik, Mohamed M. [Engineering Physics Department, Faculty of Engineering, Ain Shams University, Cairo 11566 (Egypt)

    2006-10-15

    The increasing use of Ultraviolet (UV) light in medicine, industrial environments, for cosmetic use, and even in consumer products necessitates that greater attention be paid to the potential hazards of this type of electromagnetic radiation. To avoid any adverse effects of exposure to this type of radiation, four suitable protection filters were produced to block three UV bands (UVA, UVB, and UVC). The design structure of the required dielectric multilayer filters was done by optical thin film technology using the absorbing property of UV radiation for the substrates and dielectric materials. The computer analyses of the multilayer filter formulas were prepared using Macleod Software for the production processes. The deposition technique was achieved on optical substrates (Glass BK-7 and Infrasil 301) by dielectric material combinations including Titanium dioxide (Ti{sub 2}O{sub 3}), Hafnium dioxide (HfO{sub 2}), and Lima (mixture of oxides SiO{sub 2}/Al{sub 2}O{sub 3}); deposition being achieved using an electron beam gun. The output results of the theoretical and experimental transmittance values for spectral band from 200 nm to 800 nm were discussed in four processes. To analyze the suitability for use in 'real world' applications, the test pieces were subjected to the durability tests (adhesion, abrasion resistance, and humidity) according to Military Standard MIL-C-675C and MIL-C-48497A.

  6. Determining the Solar Inactivation Rate of BK Polyomavirus by Molecular Beacon.

    Science.gov (United States)

    Reano, Dane C; Yates, Marylynn V

    2016-07-01

    The application of molecular beacons (MB) that bind to precise sequences of mRNA provides a near-universal approach in detecting evidence of viral replication. Here, we demonstrate the detection of BK Polyomavirus (BKPyV), an emerging indicator of microbiological water quality, by a quantum dot-based MB. The MB allowed us to rapidly characterize the inactivation rate of BKPyV following exposure to a solar simulator (kobs = 0.578 ± 0.024 h(-1), R(2) = 0.92). Results were validated through a traditional cell-culture assay with immunofluorescence detection (kobs = 0.568 ± 0.011 h(-1), R(2) = 0.97), which exhibited a strong correlation to MB data (R(2) = 0.93). Obtaining solar inactivation rates for BKPyV demonstrates the first use of a MB in characterizing a microbiological inactivation profile and helps assess the appropriateness of adopting BKPyV as an indicator organism for water quality. PMID:27269231

  7. The bradykinin BK2 receptor mediates angiotensin II receptor type 2 stimulated rat duodenal mucosal alkaline secretion

    Directory of Open Access Journals (Sweden)

    Helander Herbert F

    2003-02-01

    Full Text Available Abstract Background This study investigates bradykinin and nitric oxide as potential mediators of AT2-receptor-stimulated duodenal mucosal alkaline secretion. Duodenal mucosal alkaline secretion was measured in methohexital- and α-chloralose-anaesthetised rats by means of in situ pH-stat titration. Immunohistochemistry and Western blot were used to identify the BK2 receptors. Results The AT2 receptor agonist CGP42112A (0.1 μg kg-1 min-1 administered intravenously increased the duodenal mucosal alkaline secretion by ~50 %. This increase was sensitive to the selective BK2 receptor blocker HOE140 (100 ng/kg iv, but not to luminal administration of the NOS blocker L-NAME (0.3 mM. Mean arterial pressure did not differ between groups during the procedures. Immunohistochemistry showed a distinct staining of the crypt epithelium and a moderate staining of basal cytoplasm in villus enterocytes. Conclusion The results suggest that the AT2-receptor-stimulated alkaline secretion is mediated via BK2 receptors located in the duodenal cryptal mucosal epithelium.

  8. Renovascular BK(Ca) channels are not activated in vivo under resting conditions and during agonist stimulation

    DEFF Research Database (Denmark)

    Magnusson, Linda; Sørensen, Charlotte Mehlin; Braunstein, Thomas Hartig;

    2006-01-01

    of renal vascular BK(Ca) channels by cAMP was investigated by infusing forskolin. Renal blood flow (RBF) was measured in vivo using electromagnetic flowmetry or ultrasonic Doppler. Renal preinfusion of tetraethylammonium (TEA; 3.0 mumol/min) caused a small reduction of baseline RBF, but iberiotoxin...... (IBT; 0.3 nmol/min) did not have any effect. Renal injection of ANG II (1-4 ng) or NE (10-40 ng) produced a transient decrease in RBF. These responses were not affected by preinfusion of TEA or IBT. Renal infusion of the BK(Ca) opener NS-1619 (90.0 nmol/min) did not affect basal RBF or the response to...... NE, but it attenuated the response to ANG II. Coadministration of NS-1619 with TEA or IBT abolished this effect. Forskolin caused renal vasodilation that was not inhibited by IBT. The presence of BK(Ca) channels in the preglomerular vessels was confirmed by immunohistochemistry. Despite their...

  9. Expression of BKCa channels and the modulatory ß-subunits in the rat and porcine trigeminal ganglion

    DEFF Research Database (Denmark)

    Wulf-Johansson, Helle; Hay-Schmidt, Anders; Poulsen, Asser Nyander;

    2009-01-01

    Large conductance calcium-activated potassium (BK(Ca)) channels contribute to electrical impulses, proper signal transmission of information and regulation of neurotransmitter release. Migraine has been proposed to be a trigeminovascular disease involving the sensory trigeminal pathways and the c......Large conductance calcium-activated potassium (BK(Ca)) channels contribute to electrical impulses, proper signal transmission of information and regulation of neurotransmitter release. Migraine has been proposed to be a trigeminovascular disease involving the sensory trigeminal pathways...

  10. Calcium- and voltage-gated potassium (BK) channel activators in the 5β-cholanic acid-3α-ol analogue series with modifications in the lateral chain.

    Science.gov (United States)

    Bukiya, Anna N; Patil, Shivaputra A; Li, Wei; Miller, Duane D; Dopico, Alex M

    2012-10-01

    Large conductance, calcium- and voltage-gated potassium (BK) channels regulate various physiological processes and represent an attractive target for drug discovery. Numerous BK channel activators are available. However, these agents usually interact with the ubiquitously distributed channel-forming subunit and thus cannot selectively target a particular tissue. We performed a structure-activity relationship study of lithocholic acid (LCA), a cholane that activates BK channels via the accessory BK β1 subunit. The latter protein is highly abundant in smooth muscle but scarce in most other tissues. Modifications to the LCA lateral chain length and functional group yielded two novel smooth muscle BK channel activators in which the substituent at C24 has a small volume and a net negative charge. Our data provide detailed structural information that will be useful to advance a pharmacophore in search of β1 subunit-selective BK channel activators. These compounds are expected to evoke smooth muscle relaxation, which would be beneficial in the pharmacotherapy of prevalent human disorders associated with increased smooth muscle contraction, such as systemic hypertension, cerebral or coronary vasospasm, bronchial asthma, bladder hyperactivity, and erectile dysfunction. PMID:22945504

  11. Continuum limit of Bk from 2+1 flavor domain wall QCD

    International Nuclear Information System (INIS)

    We determine the neutral kaon mixing matrix element BK in the continuum limit with 2+1 flavors of domain wall fermions, using the Iwasaki gauge action at two different lattice spacings. These lattice fermions have near exact chiral symmetry and therefore avoid artificial lattice operator mixing. We introduce a significant improvement to the conventional nonperturbative renormalization (NPR) method in which the bare matrix elements are renormalized nonperturbatively in the regularization invariant momentum scheme (RI-MOM) and are then converted into the MS- scheme using continuum perturbation theory. In addition to RI-MOM, we introduce and implement four nonexceptional intermediate momentum schemes that suppress infrared nonperturbative uncertainties in the renormalization procedure. We compute the conversion factors relating the matrix elements in this family of regularization invariant symmetric momentum schemes (RI-SMOM) and MS- at one-loop order. Comparison of the results obtained using these different intermediate schemes allows for a more reliable estimate of the unknown higher-order contributions and hence for a correspondingly more robust estimate of the systematic error. We also apply a recently proposed approach in which twisted boundary conditions are used to control the Symanzik expansion for off-shell vertex functions leading to a better control of the renormalization in the continuum limit. We control chiral extrapolation errors by considering both the next-to-leading order SU(2) chiral effective theory, and an analytic mass expansion. We obtain BKMS- (3 GeV) = 0.529(5)stat(15)χ(2)FV(11)NPR. This corresponds to B-KRGI- = 0.749(7)stat(21)χ(3)FV(15)NPR. Adding all sources of error in quadrature, we obtain B-KRGI- = 0.749(27)combined, with an overall combined error of 3.6%.

  12. Analysis of real-time mixture cytotoxicity data following repeated exposure using BK/TD models.

    Science.gov (United States)

    Teng, S; Tebby, C; Barcellini-Couget, S; De Sousa, G; Brochot, C; Rahmani, R; Pery, A R R

    2016-08-15

    Cosmetic products generally consist of multiple ingredients. Thus, cosmetic risk assessment has to deal with mixture toxicity on a long-term scale which means it has to be assessed in the context of repeated exposure. Given that animal testing has been banned for cosmetics risk assessment, in vitro assays allowing long-term repeated exposure and adapted for in vitro - in vivo extrapolation need to be developed. However, most in vitro tests only assess short-term effects and consider static endpoints which hinder extrapolation to realistic human exposure scenarios where concentration in target organs is varies over time. Thanks to impedance metrics, real-time cell viability monitoring for repeated exposure has become possible. We recently constructed biokinetic/toxicodynamic models (BK/TD) to analyze such data (Teng et al., 2015) for three hepatotoxic cosmetic ingredients: coumarin, isoeugenol and benzophenone-2. In the present study, we aim to apply these models to analyze the dynamics of mixture impedance data using the concepts of concentration addition and independent action. Metabolic interactions between the mixture components were investigated, characterized and implemented in the models, as they impacted the actual cellular exposure. Indeed, cellular metabolism following mixture exposure induced a quick disappearance of the compounds from the exposure system. We showed that isoeugenol substantially decreased the metabolism of benzophenone-2, reducing the disappearance of this compound and enhancing its in vitro toxicity. Apart from this metabolic interaction, no mixtures showed any interaction, and all binary mixtures were successfully modeled by at least one model based on exposure to the individual compounds. PMID:27317371

  13. Energy up-conversion and trapping: Dynamics of 5f states of Bk4+ in CeF4

    International Nuclear Information System (INIS)

    Energy transfer mechanisms of excited 5f states of Bk4+ (0.05 atom %) in CeF4 containing circa 0.95 atom % Cf4+ have been investigated at 4 K. The observed anti-Stokes fluorescence arises from both up-conversion and two-photon excitation. Nonexponential decays of Stokes fluorescence are ascribed to both excitation-excitation annihilation and site-dependent trapping processes and, therefore, are not describable by the Inokuti-Hirayama or exciton annihilation models. Based on the Forster-Dexter energy transfer theory, a new model is developed to fit the observed fluorescence decay data. 16 refs., 3 figs

  14. Isospin Symmetry Breaking in B->K^* \\gamma Decay due to an Extra Generation of Vector Quarks

    CERN Document Server

    Ahmady, M R; Ahmady, Mohammad R.; Chishtie, Farrukh

    2005-01-01

    The extra contributions due to an extra generation of vector-like quarks to the isospin symmetry breaking observable associated with the radiative B->K^* \\gamma decay is obtained. It is shown that this additional contribution is sensitive to the nonunitarity parameter U^{sb}, which is a measure of the the strength of the non-zero tree-level flavor changing neutral current in this model. The significance of this result is that, once accurate experimental resultson the isospin asymmetry becomes available, one can constrain the U^{sb} independent of the mass of the extra quarks and so a much more stringent acceptablemodel parameter space could be obtained.

  15. Non-perturbative Renormalization of Four-Fermion Operators Relevant to $B_K$ with Staggered Quarks

    CERN Document Server

    Jeong, Hwancheol; Kim, Jongjeong; Lee, Weonjong; Pak, Jeonghwan; Park, Sungwoo

    2014-01-01

    We present preliminary results of matching factors of the four-fermion operators relevant to $B_K$, which are obtained using the non-perturbative renormalization (NPR) method in the RI-MOM scheme with HYP-smeared improved staggered fermions. We use the MILC asqtad coarse ($a \\cong 0.12\\,$fm) ensembles with $20^3 \\times 64$ geometry and $am_{\\ell}/am_s = 0.01/0.05$. We compare NPR results with those of one-loop perturbative matching.

  16. Pseudoscalar decay constants, light-quark masses, and B_K from mixed-action lattice QCD

    CERN Document Server

    Laiho, Jack

    2011-01-01

    We present updated results for the leptonic decay constants f_pi and f_K, the light u, d, and s-quark masses, and the neutral kaon mixing parameter B_K from mixed-action lattice simulations with staggered sea quarks and domain-wall valence quarks. We use the publicly-available 2+1 flavor MILC asqtad-improved staggered gauge configurations with multiple light sea-quark masses and three lattice spacings, and compute the kaon mixing matrix element with several partially-quenched valence-quark masses. We then extrapolate to the physical light-quark masses and the continuum using partially-quenched chiral perturbation theory formulated for mixed-action lattice simulations. For B_K we match the lattice four-fermion operator to the continuum using the nonperturbative method of Rome-Southampton. Our new results benefit from two significant improvements over our published work: (1) we have added a third lattice spacing of a~0.06 fm to better control the continuum extrapolation, and (2) we have implemented a new lattic...

  17. A Spectropolarimetric Comparison of the Type II-Plateau Supernovae SN 2008bk and SN 2004dj

    CERN Document Server

    Leonard, Douglas C; Hillier, D John; Pignata, Giuliano

    2011-01-01

    The Type II-Plateau supernova (SN II-P) SN 2004dj was the first SN II-P for which spectropolarimetry data were obtained with fine temporal sampling before, during, and after the fall off of the photometric plateau -- the point that marks the transition from the photospheric to the nebular phase in SNe II-P. Unpolarized during the plateau, SN 2004dj showed a dramatic spike in polarization during the descent off of the plateau, and then exhibited a smooth polarization decline over the next two hundred days. This behavior was interpreted by Leonard et al. (2006) as evidence for a strongly non-spherical explosion mechanism that had imprinted asphericity only in the innermost ejecta. In this brief report, we compare nine similarly well-sampled epochs of spectropolarimetry of the Type II-P SN 2008bk to those of SN 2004dj. In contrast to SN 2004dj, SN 2008bk became polarized well before the end of the plateau and also retained a nearly constant level of polarization through the early nebular phase. Curiously, althou...

  18. Properties of BK-type Ca++-dependent K+ channel currents in medial prefrontal cortex (PFC pyramidal neurons in rats of different ages

    Directory of Open Access Journals (Sweden)

    Bartłomiej Paweł Szulczyk

    2013-10-01

    Full Text Available The medial prefrontal cortex (PFC is involved in cognitive functions, which undergo profound changes during adolescence. This alteration of the PFC function derives from neuron activity, which, in turn, may depend on age-dependent properties and the expression of neuronal ion channels. BK-type channels are involved in controlling both the Ca++ ion concentration in the cell interior and cell excitability. The purpose of this study was to test the properties of BK currents in the medial PFC pyramidal neurons of young (18–22-day-old, adolescent (38–42-day-old and adult (58–62-day-old rats. Whole-cell currents evoked by depolarizing voltage steps were recorded from dispersed medial PFC pyramidal neurons. A selective BK channel blocker – paxilline (10 µM – irreversibly decreased the non-inactivating K+ current in neurons that were isolated from the young and adult rats. This current was not significantly affected by paxilline in the neurons obtained from adolescent rats. The properties of single-channel K+ currents were recorded from the soma of dispersed medial PFC pyramidal neurons in the cell-attached configuration. Of the K+ channel currents that were recorded, ~90% were BK and leak channel currents. The BK-type channel currents were dependent on the Ca++ concentration and the voltage and were inhibited by paxilline. The biophysical properties of the BK channel currents did not differ among the pyramidal neurons isolated from young, adolescent and adult rats. Among all of the recorded K+ channel currents, 38.9%, 12.7% and 21.1% were BK-type channel currents in the neurons isolated from the young, adolescent and adult rats, respectively. Furthermore, application of paxilline effectively prolonged the half-width of the action potential in pyramidal neurons in slices isolated from young and adult rats but not in neurons isolated from adolescent rats. We conclude that the availability of BK channel currents decreases in medial PFC

  19. Voltage-dependent Ca2+ channels, not ryanodine receptors, activate Ca2+-dependent BK potassium channels in human retinal pigment epithelial cells

    OpenAIRE

    Wimmers, Sönke; Halsband, Claire; Seyler, Sebastian; Milenkovic, Vladimir; Strauß, Olaf

    2008-01-01

    Purpose In different tissues the activation of large conductance Ca2+-activated (BK) potassium channels has been shown to be coupled to voltage-gated Ca2+ channels as well as ryanodine receptors. As activation of BK channels leads to hyperpolarization of the cell, these channels provide a negative feedback mechanism for Ca2+-induced functions. Many cellular functions of the retinal pigment epithelium (RPE) are coupled to changes in [Ca2+]i. The aim of this study was to identify which Ca2+-ent...

  20. Synthesis of a Biotin Derivative of Iberiotoxin: Binding Interactions with Streptavidin and the BK Ca2+-activated K+ Channel Expressed in a Human Cell Line

    OpenAIRE

    Bingham, Jon-Paul; Bian, Shumin; Tan, Zhi-Yong; Takacs, Zoltan; Moczydlowski, Edward

    2006-01-01

    Iberiotoxin (IbTx) is a scorpion venom peptide that inhibits BK Ca2+-activated K+ channels with high affinity and specificity. Automated solid phase synthesis was used to prepare a biotin-labeled derivative (IbTx-LC-biotin) of IbTx by substitution of Asp19 of the native 37-residue peptide with N-ε-(d-biotin-6-amidocaproate)-l-lysine. Both IbTx-LC-biotin and its complex with streptavidin (StrAv) block single BK channels from rat skeletal muscle with nanomolar affinity, indicating that the biot...

  1. ECHO virus

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/001340.htm ECHO virus To use the sharing features on this page, please enable JavaScript. Enteric cytopathic human orphan (ECHO) viruses are a group of viruses that lead to ...

  2. Energy levels of 249Bk populated in the α decay of 99253Es and β- decay of 96249Cm

    International Nuclear Information System (INIS)

    The level structure of 249Bk has been investigated by measuring the γ-ray spectra of an extremely pure 253Es sample obtained by milking this nuclide from 253Cf source material produced in the High Flux Isotope Reactor at Oak Ridge National Laboratory. Additional information on the 249Bk levels was obtained from the β--decay study of 249Cm, produced by neutron irradiation of 248Cm. Using the results of the present study together with the data from previous 248Cm(α,t) and 248Cm(3He,d) reactions, the following single-particle states have been identified in 249Bk: 7/2+[633], 0.0 keV; 3/2-[521], 8.78 keV; 1/2+[400], 377.55 keV; 5/2+[642], 389.17 keV; 1/2-[530], 569.20 keV; 1/2-[521], 643.0 keV; 5/2-[523], 672.9 keV; and 9/2+[624], 1075.1 keV. Four vibrational bands were identified at 767.9, 932.2, 1150.7, and 1223.0 keV with tentative assignments of {7/2+ [633] x1-}9/2-, {7/2+ [633] x 0-}7/2-, {7/2+ [633] x 1-}5/2-, and {7/2+ [633] x 0+}7/2+, respectively. A band at 899.9 keV was observed in γ-γ coincidence measurements and given a tentative spin assignment of 3/2. It is possibly associated with a 2- phonon coupled to the ground state, with configuration {7/2+ [633] x 2-}3/2-. Three levels at 624.3, 703.5, and 769.1 keV were assigned spins of 5/2, 7/2, and 9/2, respectively. These could be the members of the 3/2+ [651] band, expected in this energy region

  3. The BMS Equation and c\\bar{c} Production; A Comparison of the BMS and BK Equations

    CERN Document Server

    Marchesini, Giuseppe

    2015-01-01

    We introduce two processes where the BMS equation appears in a context quite different from the original context of non-global jet observables. We note the strong similarities of the BMS equation to the BK and FKPP equations and argue that these, essentially identical equations, can be viewed either in terms of the probability, or amplitude, of something not happening or in terms of the nonlinear terms setting unitarity limits. Mostly analytic solutions are given for (i) the probability that no $c\\bar{c}$ pairs be produced in a jet decay and (ii) the probability that no-$c\\bar{c}$ pairs be produced in a high energy dipole nucleus scattering. Both these processes obey BMS equations, albeit with very different kernels.

  4. A fast BK-type KCa current acts as a postsynaptic modulator of temporal selectivity for communication signals

    Directory of Open Access Journals (Sweden)

    Tsunehiko Kohashi

    2014-09-01

    Full Text Available Temporal patterns of spiking often convey behaviorally relevant information. Various synaptic mechanisms and intrinsic membrane properties can influence neuronal selectivity to temporal patterns of input. However, little is known about how synaptic mechanisms and intrinsic properties together determine the temporal selectivity of neuronal output. We tackled this question by recording from midbrain electrosensory neurons in mormyrid fish, in which the processing of temporal intervals between communication signals can be studied in a reduced in vitro preparation. Mormyrids communicate by varying interpulse intervals (IPIs between electric pulses. Within the midbrain posterior exterolateral nucleus (ELp, the temporal patterns of afferent spike trains are filtered to establish single-neuron IPI tuning. We performed whole-cell recording from ELp neurons in a whole-brain preparation and examined the relationship between intrinsic excitability and IPI tuning. We found that spike frequency adaptation of ELp neurons was highly variable. Postsynaptic potentials (PSPs of strongly adapting (phasic neurons were more sharply tuned to IPIs than weakly adapting (tonic neurons. Further, the synaptic filtering of IPIs by tonic neurons was more faithfully converted into variation in spiking output, particularly at short IPIs. Pharmacological manipulation under current- and voltage-clamp revealed that tonic firing is mediated by a fast, large-conductance Ca2+-activated K+ (KCa current (BK that speeds up action potential repolarization. These results suggest that BK currents can shape the temporal filtering of sensory inputs by modifying both synaptic responses and PSP-to-spike conversion. Slow SK-type KCa currents have previously been implicated in temporal processing. Thus, both fast and slow KCa currents can fine-tune temporal selectivity.

  5. Loss of Cav1.3 channels reveals the critical role of L-type and BK channel coupling in pacemaking mouse adrenal chromaffin cells.

    Science.gov (United States)

    Marcantoni, Andrea; Vandael, David H F; Mahapatra, Satyajit; Carabelli, Valentina; Sinnegger-Brauns, Martina J; Striessnig, Joerg; Carbone, Emilio

    2010-01-13

    We studied wild-type (WT) and Cav1.3(-/-) mouse chromaffin cells (MCCs) with the aim to determine the isoform of L-type Ca(2+) channel (LTCC) and BK channels that underlie the pacemaker current controlling spontaneous firing. Most WT-MCCs (80%) were spontaneously active (1.5 Hz) and highly sensitive to nifedipine and BayK-8644 (1,4-dihydro-2,6-dimethyl-5-nitro-4-[2-(trifluoromethyl)phenyl]-3-pyridinecarboxylic acid, methyl ester). Nifedipine blocked the firing, whereas BayK-8644 increased threefold the firing rate. The two dihydropyridines and the BK channel blocker paxilline altered the shape of action potentials (APs), suggesting close coupling of LTCCs to BK channels. WT-MCCs expressed equal fractions of functionally active Cav1.2 and Cav1.3 channels. Cav1.3 channel deficiency decreased the number of normally firing MCCs (30%; 2.0 Hz), suggesting a critical role of these channels on firing, which derived from their slow inactivation rate, sizeable activation at subthreshold potentials, and close coupling to fast inactivating BK channels as determined by using EGTA and BAPTA Ca(2+) buffering. By means of the action potential clamp, in TTX-treated WT-MCCs, we found that the interpulse pacemaker current was always net inward and dominated by LTCCs. Fast inactivating and non-inactivating BK currents sustained mainly the afterhyperpolarization of the short APs (2-3 ms) and only partially the pacemaker current during the long interspike (300-500 ms). Deletion of Cav1.3 channels reduced drastically the inward Ca(2+) current and the corresponding Ca(2+)-activated BK current during spikes. Our data highlight the role of Cav1.3, and to a minor degree of Cav1.2, as subthreshold pacemaker channels in MCCs and open new interesting features about their role in the control of firing and catecholamine secretion at rest and during sustained stimulations matching acute stress. PMID:20071512

  6. Chikungunya Virus

    Science.gov (United States)

    ... Gaines, PhD, MPH, MA, CHES Differentiating Chikungunya From Dengue: A Clinical Challenge For Travelers CDC Travelers' Health Chikungunya Virus Home Prevention Transmission Symptoms & Treatment Geographic Distribution Chikungunya virus in ...

  7. Zika Virus

    Science.gov (United States)

    Zika is a virus that is spread mostly by mosquitoes. A pregnant mother can pass it to ... through blood transfusions. There have been outbreaks of Zika virus in the United States, Africa, Southeast Asia, ...

  8. Chikungunya virus

    Science.gov (United States)

    Chikungunya virus infection; Chikungunya ... Where Chikungunya is found Before 2013, the virus was found in Africa, Asia, Europe, and the Indian and Pacific oceans. In late 2013, outbreaks occurred for the first time in the ...

  9. ECHO virus

    Science.gov (United States)

    Enteric cytopathic human orphan (ECHO) viruses are a group of viruses that lead to gastrointestinal infection and skin rashes. ... Echovirus is one of several families of viruses that affect the ... are common. In the United States, they are most common in ...

  10. Zika Virus

    Science.gov (United States)

    ... Zika Virus | See Q&A —June 21, 2016 Zika Virus Protein Could Be Vaccine Target —May 19, 2016 Research Conducted and Supported by the National Institutes of Health (NIH) in Addressing Zika Virus Disease. Testimony before the House Democratic Steering ...

  11. Marketingová situační analýza BK Lions Jindřichův Hradec

    OpenAIRE

    Hron, Patrik

    2014-01-01

    The aim of this bachelor thesis is to carry out an analysis of each part of marketing mix and the environment in which the BK Lions Jindřichův Hradec basketball club is situated. Suitable and applicable recommendations are suggested to make the marketing mix more effective based on analysis of marketing situation. The first part is focused on describing the marketing mix and marketing situational analysis at a theoretical level. The practical part describes particular marketing tools which ar...

  12. Gentamicin Blocks the ACh-Induced BK Current in Guinea Pig Type II Vestibular Hair Cells by Competing with Ca2+ at the l-Type Calcium Channel

    Directory of Open Access Journals (Sweden)

    Hong Yu

    2014-04-01

    Full Text Available Type II vestibular hair cells (VHCs II contain big-conductance Ca2+-dependent K+ channels (BK and L-type calcium channels. Our previous studies in guinea pig VHCs II indicated that acetylcholine (ACh evoked the BK current by triggering the influx of Ca2+ ions through l-type Ca2+ channels, which was mediated by M2 muscarinic ACh receptor (mAChRs. Aminoglycoside antibiotics, such as gentamicin (GM, are known to have vestibulotoxicity, including damaging effects on the efferent nerve endings on VHCs II. This study used the whole-cell patch clamp technique to determine whether GM affects the vestibular efferent system at postsynaptic M2-mAChRs or the membrane ion channels. We found that GM could block the ACh-induced BK current and that inhibition was reversible, voltage-independent, and dose-dependent with an IC50 value of 36.3 ± 7.8 µM. Increasing the ACh concentration had little influence on GM blocking effect, but increasing the extracellular Ca2+ concentration ([Ca2+]o could antagonize it. Moreover, 50 µM GM potently blocked Ca2+ currents activated by (--Bay-K8644, but did not block BK currents induced by NS1619. These observations indicate that GM most likely blocks the M2 mAChR-mediated response by competing with Ca2+ at the l-type calcium channel. These results provide insights into the vestibulotoxicity of aminoglycoside antibiotics on mammalian VHCs II.

  13. Distinct BK polyomavirus non-coding control region (NCCR) variants in oral fluids of HIV- associated Salivary Gland Disease patients.

    Science.gov (United States)

    Burger-Calderon, Raquel; Ramsey, Kathy J; Dolittle-Hall, Janet M; Seaman, William T; Jeffers-Francis, Liesl K; Tesfu, Daniel; Nickeleit, Volker; Webster-Cyriaque, Jennifer

    2016-06-01

    HIV-associated Salivary Gland Disease (HIVSGD) is among the most common salivary gland-associated complications in HIV positive individuals and was associated with the small DNA tumorvirus BK polyomavirus (BKPyV). The BKPyV non-coding control region (NCCR) is the main determinant of viral replication and rearranges readily. This study analyzed the BKPyV NCCR architecture and viral loads of 35 immunosuppressed individuals. Throatwash samples from subjects diagnosed with HIVSGD and urine samples from transplant patients were BKPyV positive and yielded BKPyV NCCR sequences. 94.7% of the BKPyV HIVSGD NCCRs carried a rearranged OPQPQQS block arrangement, suggesting a distinct architecture among this sample set. BKPyV from HIV positive individuals without HIVSGD harbored NCCR block sequences that were distinct from OPQPQQS. Cloned HIVSGD BKPyV isolates displayed active promoters and efficient replication capability in human salivary gland cells. The unique HIVSGD NCCR architecture may represent a potentially significant oral-tropic BKPyV substrain. PMID:27085139

  14. Impact of mTORC1 inhibition on keratinocyte proliferation during skin tumor promotion in wild-type and BK5.AktWT mice.

    Science.gov (United States)

    Rho, Okkyung; Kiguchi, Kaoru; Jiang, Guiyu; DiGiovanni, John

    2014-11-01

    In this study, we examined the impact of rapamycin on mTORC1 signaling during 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced keratinocyte proliferation and skin tumor promotion in both wild-type (FVB/N) and BK5.Akt(WT) mice. TPA activated mTORC1 signaling in a time-dependent manner in cultured primary mouse keratinocytes and a mouse keratinocyte cell line. Early activation (15-30 min) of mTORC1 signaling induced by TPA was mediated in part by PKC activation, whereas later activation (2-4 h) was mediated by activation of EGFR and Akt. BK5.Akt(WT) transgenic mice, where Akt1 is overexpressed in basal epidermis, are highly sensitive to TPA-induced epidermal proliferation and two-stage skin carcinogenesis. Targeting mTORC1 with rapamycin effectively inhibited TPA-induced epidermal hyperplasia and hyperproliferation as well as tumor promotion in a dose-dependent manner in both wild-type and BK5.Akt(WT) mice. A significant expansion (∼threefold) of the label retaining cell (LRC) population per hair follicle was observed in BK5.Akt(WT) mice compared to FVB/N mice. There was also a significant increase in K15 expressing cells in the hair follicle of transgenic mice that coincided with expression of phospho-Akt, phospho-S6K, and phospho-PRAS40, suggesting an important role of mTORC1 signaling in bulge-region keratinocyte stem cell (KSC) homeostasis. After 2 weeks of TPA treatment, LRCs had moved upward into the interfollicular epidermis from the bulge region of both wild-type and BK5.Akt(WT) mice. TPA-mediated LRC proliferation and migration was significantly inhibited by rapamycin. Collectively, the current data indicate that signaling through mTORC1 contributes significantly to the process of skin tumor promotion through effects on proliferation of the target cells for tumor development. PMID:24114993

  15. Computed Tomography Findings of Human Polyomavirus BK (BKV)-Associated Cystitis in Allogeneic Hematopoietic Stem Cell Transplant Recipients

    Energy Technology Data Exchange (ETDEWEB)

    Schulze, M.; Beck, R.; Igney, A.; Vogel, M.; Maksimovic, O.; Claussen, C.D.; Faul, C.; Horger, M. [Dept. of Diagnostic Radiology, Dept. of Internal Medicine-Oncology, and Inst. of Medical Virology, Eberhard-Karls Univ., Tbingen (Germany)

    2008-12-15

    Background: Over 70% of the general population worldwide is positive for antibodies against polyomavirus hominis type 1 (BKV). Polyomavirus can be reactivated in immunocompromised patients and thereby induce urogenital tract infection, including cystitis. Purpose: To describe the computed tomography (CT) findings of human polyomavirus-induced cystitis in adult patients after allogeneic hematopoietic stem cell transplantation (allogeneic HCT). Material and Methods: The study population was a retrospective cohort of 11 consecutive adult patients (eight men, three women; age range 22-59 years, mean 42.9 years) who received allogeneic HCT between December 2003 and December 2007 and were tested positive for urinary BKV infection. All CT scans were evaluated with regard to bladder wall thickness, mucosal enhancement, distinct layering of thickened bladder wall, and presence of intravesical clots, perivesical stranding as well as attenuation values of intravesical urine. Clinical data concerning transplant and conditioning regimen variables and laboratory parameters were correlated with degree and extent of imaging findings. Results: All patients had clinical signs of cystitis with different degrees of thickening of the urinary bladder wall. Well-delineated urinary bladder layers were present in six patients. Thickening of the urinary bladder wall was continuous in nine of 11 patients. Increased attenuation of intravesical urine was found in seven patients with hemorrhagic cystitis. Four patients had intraluminal clots. Perivesical stranding was not a major CT finding, occurring in a mild fashion in three of 11 patients. The clinical classification of hemorrhagic cystitis did not correlate with the analyzed imaging parameters. Patient outcome was not influenced by this infectious complication. Conclusion: CT findings in patients with polyomavirus BK cystitis consist of different degrees of bladder wall thickening usually with good delineation of all mural layers and

  16. Computed Tomography Findings of Human Polyomavirus BK (BKV)-Associated Cystitis in Allogeneic Hematopoietic Stem Cell Transplant Recipients

    Energy Technology Data Exchange (ETDEWEB)

    Schulze, M.; Beck, R.; Igney, A.; Vogel, M.; Maksimovic, O.; Claussen, C.D.; Faul, C.; Horger, M. (Dept. of Diagnostic Radiology, Dept. of Internal Medicine-Oncology, and Inst. of Medical Virology, Eberhard-Karls Univ., Tbingen (Germany))

    2008-12-15

    Background: Over 70% of the general population worldwide is positive for antibodies against polyomavirus hominis type 1 (BKV). Polyomavirus can be reactivated in immunocompromised patients and thereby induce urogenital tract infection, including cystitis. Purpose: To describe the computed tomography (CT) findings of human polyomavirus-induced cystitis in adult patients after allogeneic hematopoietic stem cell transplantation (allogeneic HCT). Material and Methods: The study population was a retrospective cohort of 11 consecutive adult patients (eight men, three women; age range 22-59 years, mean 42.9 years) who received allogeneic HCT between December 2003 and December 2007 and were tested positive for urinary BKV infection. All CT scans were evaluated with regard to bladder wall thickness, mucosal enhancement, distinct layering of thickened bladder wall, and presence of intravesical clots, perivesical stranding as well as attenuation values of intravesical urine. Clinical data concerning transplant and conditioning regimen variables and laboratory parameters were correlated with degree and extent of imaging findings. Results: All patients had clinical signs of cystitis with different degrees of thickening of the urinary bladder wall. Well-delineated urinary bladder layers were present in six patients. Thickening of the urinary bladder wall was continuous in nine of 11 patients. Increased attenuation of intravesical urine was found in seven patients with hemorrhagic cystitis. Four patients had intraluminal clots. Perivesical stranding was not a major CT finding, occurring in a mild fashion in three of 11 patients. The clinical classification of hemorrhagic cystitis did not correlate with the analyzed imaging parameters. Patient outcome was not influenced by this infectious complication. Conclusion: CT findings in patients with polyomavirus BK cystitis consist of different degrees of bladder wall thickening usually with good delineation of all mural layers and

  17. Computed Tomography Findings of Human Polyomavirus BK (BKV)-Associated Cystitis in Allogeneic Hematopoietic Stem Cell Transplant Recipients

    International Nuclear Information System (INIS)

    Background: Over 70% of the general population worldwide is positive for antibodies against polyomavirus hominis type 1 (BKV). Polyomavirus can be reactivated in immunocompromised patients and thereby induce urogenital tract infection, including cystitis. Purpose: To describe the computed tomography (CT) findings of human polyomavirus-induced cystitis in adult patients after allogeneic hematopoietic stem cell transplantation (allogeneic HCT). Material and Methods: The study population was a retrospective cohort of 11 consecutive adult patients (eight men, three women; age range 22-59 years, mean 42.9 years) who received allogeneic HCT between December 2003 and December 2007 and were tested positive for urinary BKV infection. All CT scans were evaluated with regard to bladder wall thickness, mucosal enhancement, distinct layering of thickened bladder wall, and presence of intravesical clots, perivesical stranding as well as attenuation values of intravesical urine. Clinical data concerning transplant and conditioning regimen variables and laboratory parameters were correlated with degree and extent of imaging findings. Results: All patients had clinical signs of cystitis with different degrees of thickening of the urinary bladder wall. Well-delineated urinary bladder layers were present in six patients. Thickening of the urinary bladder wall was continuous in nine of 11 patients. Increased attenuation of intravesical urine was found in seven patients with hemorrhagic cystitis. Four patients had intraluminal clots. Perivesical stranding was not a major CT finding, occurring in a mild fashion in three of 11 patients. The clinical classification of hemorrhagic cystitis did not correlate with the analyzed imaging parameters. Patient outcome was not influenced by this infectious complication. Conclusion: CT findings in patients with polyomavirus BK cystitis consist of different degrees of bladder wall thickening usually with good delineation of all mural layers and

  18. Application of immunoperoxidase staining to more rapid detection and identification of rubella virus isolates.

    OpenAIRE

    Schmidt, N J; Ho, H H; Chin, J

    1981-01-01

    Efforts were made to shorten the time required for detection of rubella virus in clinical materials through the use of immunoperoxidase (IP) staining. Comparative studies were performed in which specimens were inoculated in parallel into BHK-21 hamster kidney cells, which were examined by IP staining at 5 days, and into BK-13 and BS-C-1 cells, which were examined in two ways, viz., by subpassage at 7 days into BHK-21 cells and IP staining 3 days later and by subpassage at 7 days into BS-C-1 c...

  19. Computer Virus

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Computer viruses are small software programs that are designed to spread from one computerto another and to interfere with computer operation.A virus might delete data on your computer,use your e-mail program to spread itself to othercomputers,or even erase everything on your hard disk.Viruses are most easily spread by attach-ments in e-mail messages or instant messaging messages.That is why it is essential that you never

  20. Impact of mTORC1 Inhibition on Keratinocyte Proliferation During Skin Tumor Promotion in Wild-Type and BK5.AktWT Mice

    OpenAIRE

    Rho, Okkyung; Kiguchi, Kaoru; Jiang, Guiyu; DiGiovanni, John

    2013-01-01

    In this study, we examined the impact of rapamycin on mTORC1 signaling during 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced keratinocyte proliferation and skin tumor promotion in both wild-type (FVB/N) and BK5.AktWT mice. TPA activated mTORC1 signaling in a time-dependent manner in cultured primary mouse keratinocytes and a mouse keratinocyte cell line. Early activation (15–30 min) of mTORC1 signaling induced by TPA was mediated in part by PKC activation, whereas later activation (2–4 h)...

  1. Computer viruses

    Science.gov (United States)

    Denning, Peter J.

    1988-01-01

    The worm, Trojan horse, bacterium, and virus are destructive programs that attack information stored in a computer's memory. Virus programs, which propagate by incorporating copies of themselves into other programs, are a growing menace in the late-1980s world of unprotected, networked workstations and personal computers. Limited immunity is offered by memory protection hardware, digitally authenticated object programs,and antibody programs that kill specific viruses. Additional immunity can be gained from the practice of digital hygiene, primarily the refusal to use software from untrusted sources. Full immunity requires attention in a social dimension, the accountability of programmers.

  2. Immunogenicity and protection from malaria infection in BK-SE36 vaccinated volunteers in Uganda is not influenced by HLA-DRB1 alleles.

    Science.gov (United States)

    Tougan, Takahiro; Ito, Kazuya; Palacpac, Nirianne Marie Q; Egwang, Thomas G; Horii, Toshihiro

    2016-10-01

    SE36 antigen, derived from serine repeat antigen 5 (SERA5) of Plasmodium falciparum, is a promising blood stage malaria vaccine candidate. Designated as BK-SE36, the SE36 antigen was formulated with aluminum hydroxyl gel (AHG) and produced under Good Manufacturing Practice (GMP) constraints. In a Phase Ib clinical trial and follow-up study in Uganda, the risk for malaria symptoms was reduced by 72% compared with the control group. Although promising, the number of responders to the vaccine in 6-20years-olds was approximately 30% with the majority in the younger cohort. This is in contrast to the phase Ia clinical trial where response to the vaccine was 100% in Japanese malaria naive adults. A consideration that can be of importance is the involvement of host genetic factors that may influence the ability to mount an effective immune response to vaccination as well as susceptibility to malaria infection. We, therefore, analyzed allelic polymorphism of human leukocyte antigen (HLA)-DRB1 alleles using sequence-based typing (SBT). In this study, DRB1 alleles did not influence antibody response to BK-SE36 and the vaccinees susceptibility to clinical malaria. PMID:27343834

  3. Zika Virus.

    Science.gov (United States)

    Phillips, Jennan A; Neyland, Anavernyel

    2016-08-01

    Zika virus (ZIKV) infections are the latest global public health emergency. Occupational health nurses can protect society by educating workers, women of childbearing age, and others traveling in ZIKV-infected areas about prevention strategies. PMID:27411846

  4. Live Virus Smallpox Vaccine

    Science.gov (United States)

    ... A - Z Index SMALLPOX FACT SHEET The Live Virus Smallpox Vaccine The vaccinia virus is the "live ... it cannot cause smallpox. What is a "live virus" vaccine? A "live virus" vaccine is a vaccine ...

  5. Computer Viruses. Technology Update.

    Science.gov (United States)

    Ponder, Tim, Comp.; Ropog, Marty, Comp.; Keating, Joseph, Comp.

    This document provides general information on computer viruses, how to help protect a computer network from them, measures to take if a computer becomes infected. Highlights include the origins of computer viruses; virus contraction; a description of some common virus types (File Virus, Boot Sector/Partition Table Viruses, Trojan Horses, and…

  6. Large N approach to Kaon decays and mixing 28 years later. ΔI = 1/2 rule, BK, and ΔMK

    International Nuclear Information System (INIS)

    We review and update our results for K → ππ decays and K0- anti K0 mixing obtained by us in the 1980s within an analytic approximate approach based on the dual representation of QCD as a theory of weakly interacting mesons for large N, where N is the number of colors. In our analytic approach the Standard Model dynamics behind the enhancement of ReA0 and suppression of ReA2, the so called ΔI = 1/2 rule for K → ππ decays, has a simple structure: the usual octet enhancement through the long but slow quark - gluon renormalization group evolution down to the scales O(1 GeV) is continued as a short but fast meson evolution down to zero momentum scales at which the factorization of hadronic matrix elements is at work. The inclusion of lowest-lying vector meson contributions in addition to the pseudoscalar ones and of Wilson coefficients in a momentum scheme improves significantly the matching between quark - gluon and meson evolutions. In particular, the anomalous dimension matrix governing the meson evolution exhibits the structure of the known anomalous dimension matrix in the quark - gluon evolution. While this physical picture did not yet emerge from lattice simulations, the recent results on ReA2 and ReA0 from the RBC-UKQCD collaboration give support for its correctness. In particular, the signs of the two main contractions found numerically by these authors follow uniquely from our analytic approach. Though the current - current operators dominate the ΔI = 1/2 rule, working with matching scales O(1 GeV) we find that the presence of QCD-penguin operator Q6 is required to obtain satisfactory result for ReA0. At NLO in 1/N we obtain R = ReA0/ReA2 = 16.0 ± 1.5 which amounts to an order of magnitude enhancement over the strict large N limit value √(2). We also update our results for the parameter BK, finding BK = 0.73 ± 0.02. The smallness of 1/N corrections to the large N value BK = 3/4 results within our approach from an approximate cancelation between

  7. Ebola Virus

    Directory of Open Access Journals (Sweden)

    Anusha Rangare Lakshman

    2015-09-01

    Full Text Available The disease Ebola takes its name from the Ebola River situated near a village in the Democratic Republic of Congo, where the disease first appeared in 1976. It is caused by a virus from the Filoviridae family (filovirus. The present outbreak of Ebola Virus Disease (EVD concerns four countries in West Africa, namely Guinea, Liberia, Sierra Leone and Nigeria till date. Further to widespread transmission of the disease, it has been declared as a Public Health Emergency of International Concern by the World Health Organisation on 8 August 2014. As of 4 August 2014, countries have reported 1,711 cases (1,070 confirmed, 436 probable, 205 suspect, including 932 deaths. This review paper enlightens about the awareness of Ebola virus and its preventive measures. [Archives Medical Review Journal 2015; 24(3.000: 296-305

  8. Toxin-antitoxin loci as stress-response-elements: ChpAK/MazF and ChpBK cleave translated RNAs and are counteracted by tmRNA

    DEFF Research Database (Denmark)

    Christensen, S.K.; Pedersen, K.; Hansen, Flemming G.;

    2003-01-01

    Prokaryotic chromosomes encode toxin-antitoxin loci, often in multiple copies. In most cases, the function of these genes is not known. The chpA (mazEF) locus of Escherichia coli has been described as a cell killing module that induces bacterial apoptosis during nutritional stress. However, we...... found recently that ChpAK (MazF) does not confer cell killing but rather, induces a bacteriostatic condition from which the cells could be resuscitated. Results presented here yield a mechanistic explanation for the detrimental effect on cell growth exerted by ChpAK and the homologous ChpBK protein of E....... coli. We show that both proteins inhibit translation by inducing cleavage of translated mRNAs. Consistently, the inhibitory effect of the proteins was counteracted by tmRNA. Amino acid starvation induced strong transcription of chpA that depended on Lon protease but not on ppGpp. Simultaneously, Chp...

  9. Observation of a resonance-like structure in the pi^+- psi' mass distribution in exclusive B-->K pi^+- psi' decays

    CERN Document Server

    Abe, K; Aihara, H; Arinstein, K; Aso, T; Aulchenko, V; Aushev, T; Aziz, T; Bahinipati, S; Bakich, A M; Balagura, V; Ban, Y; Banerjee, S; Barberio, E; Bay, A; Bedny, I; Belous, K S; Bhardwaj, V; Bitenc, U; Blyth, S; Bondar, A; Bozek, A; Bracko, M; Brodzicka, J; Browder, T E; Chang, M C; Chang, P; Chao, Y; Chen, A; Chen, K F; Chen, W T; Cheon, B G; Chiang, C C; Chistov, R; Cho, I S; Choi, S K; Choi, Y; Choi, Y K; Cole, S; Dalseno, J; Danilov, M; Das, A; Dash, M; Dragic, J; Drutskoy, A; Eidelman, S; Epifanov, D; Fratina, S; Fujii, H; Fujikawa, M; Gabyshev, N; Garmash, A; Go, A; Gokhroo, G; Goldenzweig, P; Golob, B; Grosse-Perdekamp, M; Guler, H; Ha, H; Haba, J; Hara, K; Hara, T; Hasegawa, Y; Hastings, N C; Hayasaka, K; Hayashii, H; Hazumi, M; Heffernan, D; Higuchi, T; Hinz, L; Hoedlmoser, H; Hokuue, T; Horii, Y; Hoshi, Y; Hoshina, K; Hou, S; Hou, W S; Hsiung, Y B; Hyun, H J; Igarashi, Y; Iijima, T; Ikado, K; Inami, K; Ishikawa, A; Ishino, H; Itoh, R; Iwabuchi, M; Iwasaki, M; Iwasaki, Y; Jacoby, C; Joshi, N J; Kaga, M; Kah, D H; Kaji, H; Kajiwara, S; Kakuno, H; Kang, J H; Kapusta, P; Kataoka, S U; Katayama, N; Kawai, H; Kawasaki, T; Kibayashi, A; Kichimi, H; Kim, H J; Kim, H O; Kim, J H; Kim, S K; Kim, Y J; Kinoshita, K; Korpar, S; Kozakai, Y; Krizan, P; Krokovny, P; Kumar, R; Kurihara, E; Kusaka, A; Kuzmin, A; Kwon, Y J; Lange, J S; Leder, G; Lee, J; Lee, J S; Lee, M J; Lee, S E; Lesiak, T; Li, J; Limosani, A; Lin, S W; Liu, Y; Liventsev, D; MacNaughton, J; Majumder, G; Mandl, F; Marlow, D; Matsumura, T; Matyja, A; McOnie, S; Medvedeva, T; Mikami, Y; Mitaroff, W A; Miyabayashi, K; Miyake, H; Miyata, H; Miyazaki, Y; Mizuk, R; Moloney, G R; Mori, T; Müller, J; Murakami, A; Nagamine, T; Nagasaka, Y; Nakahama, Y; Nakamura, I; Nakano, E; Nakao, M; Nakayama, H; Nakazawa, H; Natkaniec, Z; Neichi, K; Nishida, S; Nishimura, K; Nishio, Y; Nishizawa, I; Nitoh, O; Noguchi, S; Nozaki, T; Ogawa, A; Ogawa, S; Ohshima, T; Okuno, S; Olsen, S L; Ono, S; Ostrowicz, W; Ozaki, H; Pakhlov, P; Pakhlova, G; Palka, H; Park, C W; Park, H; Park, K S; Parslow, N; Peak, L S; Pernicka, M; Pestotnik, R; Peters, M; Piilonen, L E; Poluektov, A; Rorie, J; Rózanska, M; Sahoo, H; Sakai, Y; Sakamoto, H; Sakaue, H; Sarangi, T R; Satoyama, N; Sayeed, K; Schietinger, T; Schneider, O; Schonmeier, P; Schümann, J; Schwanda, C; Schwartz, A J; Seidl, R; Sekiya, A; Senyo, K; Sevior, M E; Shang, L; Shapkin, M; Shen, C P; Shibuya, H; Shinomiya, S; Shiu, J G; Shwartz, B; Singh, J B; Sokolov, A; Solovieva, E; Somov, A; Stanic, S; Staric, M; Stypula, J; Sugiyama, A; Sumisawa, K; Sumiyoshi, T; Suzuki, S; Suzuki, S Y; Tajima, O; Takasaki, F; Tamai, K; Tamura, N; Tanaka, M; Taniguchi, N; Taylor, G N; Teramoto, Y; Tikhomirov, I; Trabelsi, K; Tse, Y F; Tsuboyama, T; Uchida, K; Uchida, Y; Uehara, S; Ueno, K; Uglov, T; Unno, Y; Uno, S; Urquijo, P; Ushiroda, Y; Usov, Yu; Varner, G; Varvell, K E; Vervink, K; Villa, S; Vinokurova, A; Wang, C C; Wang, C H; Wang, J; Wang, M Z; Wang, P; Wang, X L; Watanabe, M; Watanabe, Y; Wedd, R; Wicht, J; Widhalm, L; Wiechczynski, J; Won, E; Yabsley, B D; Yamaguchi, A; Yamamoto, H; Yamaoka, M; Yamashita, Y; Yamauchi, M; Yuan, C Z; Yusa, Y; Zhang, C C; Zhang, L M; Zhang, Z P; Zhilich, V; Zhulanov, V; Zupanc, A; Zwahlen, N

    2007-01-01

    A distinct peak is observed in the pi^+/- psi' invariant mass distribution near 4.43 GeV in B->K pi^+/- psi' decays. A fit using a Breit Wigner resonance shape yields a peak mass and width of 4433+-4(stat)+-1(syst) MeV and Gamma = 44^+17_-13(stat) ^+30_-11 MeV. The product branching fraction is determined to be Bf(B-->KZ(4430))xBf(Z(4430)-->pi^+psi') = (4.1+-1.0(stat)+-1.3(syst))x10^{-5), where Z(4430) is used to designate the observed structure. The statistical significance of the observed peak is greater than 7sigma. These results are obtained from a 605 fb-1 data sample that contains 657 million BBbar pairs collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+e- collider.

  10. Eleven new heaviest isotopes of elements Z=105 to Z=117 identified among the products of 249Bk+48Ca reactions

    International Nuclear Information System (INIS)

    The heaviest isotopes of elements Z=117 to Z=105, 294117, 293117, 290115, 289115, 286113, 285113, 282Rg, 281Rg, 278Mt, 274Bh, and 270Db, were identified by means of the Dubna gas-filled recoil separator among the products of the 249Bk + 48Ca reaction. The details of the observed six decay chains, indicating the production and decay of isotopes 293117 and 294117, are presented and discussed. The decay energies and resulting half-lives of these new nuclei show a strong rise of stability with increasing neutron number, validating the concept of the island of enhanced stability for superheavy nuclei [Oganessian et al., Phys. Rev. Lett. 104, 142502 (2010)].

  11. Detection and characterization of human pathogenic viruses circulating in community wastewater using multi target microarrays and polymerase chain reaction.

    Science.gov (United States)

    Wong, Mark V M; Hashsham, Syed A; Gulari, Erdogan; Rouillard, Jean-Marie; Aw, Tiong Gim; Rose, Joan B

    2013-12-01

    Sewage pollution remains the most significant source of human waterborne pathogens. This study describes the detection and characterization of human enteric viruses in community wastewaters using cell culture coupled with multiple target microarrays (with a total of 780 unique probes targeting 27 different groups of both DNA and RNA viruses) and polymerase chain reaction (PCR) assays. Over a 13-month sampling period, RNA viruses (astroviruses and enteroviruses) were more frequently detected compared to DNA viruses (adenoviruses, particularly type 41 and BK polyomavirus). Overall, many more viruses were shed during the winter months (December-February) compared to the summer months. Exploration of the multiple types of enteric viruses particularly in winter months identified much more significant prevalence of key viral pathogens associated with sewage pollution of the water environment than previously realized and seasonal disinfection used in some parts of the world may lead to a seeding of ambient waters. Molecular characterization of pathogenic viruses in community wastewater will improve the understanding of the potential risk of waterborne disease transmission of viral pathogens. PMID:24334840

  12. Passatempo Virus, a Vaccinia Virus Strain, Brazil

    OpenAIRE

    Leite, Juliana A.; Drumond, Betânia P.; Trindade, Giliane S; Zélia I P Lobato; da Fonseca, Flávio G.; dos Santos, João R.; Madureira, Marieta C.; Guedes, Maria I.M.C.; Ferreira, Jaqueline M. S.; Bonjardim, Cláudio A.; Ferreira, Paulo C. P.; Kroon, Erna G.

    2005-01-01

    Passatempo virus was isolated during a zoonotic outbreak. Biologic features and molecular characterization of hemagglutinin, thymidine kinase, and vaccinia growth factor genes suggested a vaccinia virus infection, which strengthens the idea of the reemergence and circulation of vaccinia virus in Brazil. Molecular polymorphisms indicated that Passatempo virus is a different isolate.

  13. Oropuche virus: A virus present but ignored

    Directory of Open Access Journals (Sweden)

    Salim Mattar V.

    2015-09-01

    Full Text Available Bunyaviruses are RNA viruses that affect animals and plants; they have five genera and four of them affect humans: Orthobunyavirus, Nairovirus, Phlebovirus and Hantavirus. All of them are Arbovirus, except Hantavirus. The Orthobunyaviruses comprise Oropouche, Tahyna, La Crosse virus, California encephalitis virus and Heartland virus recently discovered (1. Except for Heartland virus which is transmitted by ticks of the genus Amblyoma, these Phleboviruses have as vectors mosquitoes, which bite small mammals which are able to be as reservoirs amplifiers.

  14. Plant Virus Metagenomics: Advances in Virus Discovery.

    Science.gov (United States)

    Roossinck, Marilyn J; Martin, Darren P; Roumagnac, Philippe

    2015-06-01

    In recent years plant viruses have been detected from many environments, including domestic and wild plants and interfaces between these systems-aquatic sources, feces of various animals, and insects. A variety of methods have been employed to study plant virus biodiversity, including enrichment for virus-like particles or virus-specific RNA or DNA, or the extraction of total nucleic acids, followed by next-generation deep sequencing and bioinformatic analyses. All of the methods have some shortcomings, but taken together these studies reveal our surprising lack of knowledge about plant viruses and point to the need for more comprehensive studies. In addition, many new viruses have been discovered, with most virus infections in wild plants appearing asymptomatic, suggesting that virus disease may be a byproduct of domestication. For plant pathologists these studies are providing useful tools to detect viruses, and perhaps to predict future problems that could threaten cultivated plants. PMID:26056847

  15. Zika Virus.

    Science.gov (United States)

    Musso, Didier; Gubler, Duane J

    2016-07-01

    Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the genus Flavivirus and the family Flaviviridae. ZIKV was first isolated from a nonhuman primate in 1947 and from mosquitoes in 1948 in Africa, and ZIKV infections in humans were sporadic for half a century before emerging in the Pacific and the Americas. ZIKV is usually transmitted by the bite of infected mosquitoes. The clinical presentation of Zika fever is nonspecific and can be misdiagnosed as other infectious diseases, especially those due to arboviruses such as dengue and chikungunya. ZIKV infection was associated with only mild illness prior to the large French Polynesian outbreak in 2013 and 2014, when severe neurological complications were reported, and the emergence in Brazil of a dramatic increase in severe congenital malformations (microcephaly) suspected to be associated with ZIKV. Laboratory diagnosis of Zika fever relies on virus isolation or detection of ZIKV-specific RNA. Serological diagnosis is complicated by cross-reactivity among members of the Flavivirus genus. The adaptation of ZIKV to an urban cycle involving humans and domestic mosquito vectors in tropical areas where dengue is endemic suggests that the incidence of ZIKV infections may be underestimated. There is a high potential for ZIKV emergence in urban centers in the tropics that are infested with competent mosquito vectors such as Aedes aegypti and Aedes albopictus. PMID:27029595

  16. Computer Viruses: An Overview.

    Science.gov (United States)

    Marmion, Dan

    1990-01-01

    Discusses the early history and current proliferation of computer viruses that occur on Macintosh and DOS personal computers, mentions virus detection programs, and offers suggestions for how libraries can protect themselves and their users from damage by computer viruses. (LRW)

  17. Viruses Infecting Reptiles

    OpenAIRE

    Marschang, Rachel E.

    2011-01-01

    A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The ...

  18. Oncogenic viruses and cancer

    Institute of Scientific and Technical Information of China (English)

    Guangxiang; George; Luo; Jing-hsiung; James; Ou

    2015-01-01

    <正>This special issue of the journal is dedicated to the important topic of oncogenic viruses and cancer.It contains seven review articles covering all known oncogenic viruses except for human T-lymphotropic virus type1(HTLV-1).These review articles are contributed by experts on specific viruses and their associated human cancers.Viruses account for about 20%of total human cancer cases.Although many viruses can cause various tumors in animals,only seven of them

  19. p53 targets simian virus 40 large T antigen for acetylation by CBP.

    Science.gov (United States)

    Poulin, Danielle L; Kung, Andrew L; DeCaprio, James A

    2004-08-01

    Simian virus 40 (SV40) large T antigen (T Ag) interacts with the tumor suppressor p53 and the transcriptional coactivators CBP and p300. Binding of these cellular proteins in a ternary complex has been implicated in T Ag-mediated transformation. It has been suggested that the ability of CBP/p300 to modulate p53 function underlies p53's regulation of cell proliferation and tumorigenesis. In this study, we provide further evidence that CBP activity may be mediated through its synergistic action with p53. We demonstrate that SV40 T Ag is acetylated in vivo in a p53-dependent manner and T Ag acetylation is largely mediated by CBP. The acetylation of T Ag is dependent on its interaction with p53 and on p53's interaction with CBP. We have mapped the site of acetylation on T Ag to the C-terminal lysine residue 697. This acetylation site is conserved between the T antigens of the human polyomaviruses JC and BK, which are also known to interact with p53. We show that both JC and BK T antigens are also acetylated at corresponding sites in vivo. While other proteins are known to be acetylated by CBP/p300, none are known to depend on p53 for acetylation. T Ag acetylation may provide a regulatory mechanism for T Ag binding to a cellular factor or play a role in another aspect of T Ag function. PMID:15254196

  20. Virus Movement Maintains Local Virus Population Diversity

    Energy Technology Data Exchange (ETDEWEB)

    J. Snyder; B. Wiedenheft; M. Lavin; F. Roberto; J. Spuhler; A. Ortmann; T. Douglas; M. Young

    2007-11-01

    Viruses are the largest reservoir of genetic material on the planet, yet little is known about the population dynamics of any virus within its natural environment. Over a 2-year period, we monitored the diversity of two archaeal viruses found in hot springs within Yellowstone National Park (YNP). Both temporal phylogeny and neutral biodiversity models reveal that virus diversity in these local environments is not being maintained by mutation but rather by high rates of immigration from a globally distributed metacommunity. These results indicate that geographically isolated hot springs are readily able to exchange viruses. The importance of virus movement is supported by the detection of virus particles in air samples collected over YNP hot springs and by their detection in metacommunity sequencing projects conducted in the Sargasso Sea. Rapid rates of virus movement are not expected to be unique to these archaeal viruses but rather a common feature among virus metacommunities. The finding that virus immigration rather than mutation can dominate community structure has significant implications for understanding virus circulation and the role that viruses play in ecology and evolution by providing a reservoir of mobile genetic material.

  1. Application of a real-time PCR assay to detect BK potassium channel expression in samples from Atlantic salmon (Salmo salar and Rainbow trout (Oncorhynchus mykiss acclimated to freshwater#

    Directory of Open Access Journals (Sweden)

    CA Loncoman

    2015-01-01

    Full Text Available Atlantic salmon (Salmo salar and Rainbow trout (Oncorhynchus mykiss are two fish species that spawn in fresh water (FW and, during development, acclimate to seawater (SW by secreting excess NaCl to the environment. The salmon industry measures Na+/K+ ATPase (NKA activity as a molecular marker to determine the timing of smolt transfer from FW to SW. However, the lack of other accurate molecular markers of smoltification remains a major issue for the fish farming industry. The molecular mechanism of NaCl secretion in gills from SW-acclimated fish has a thermodynamic requirement to recycle K+ out of the cell via potassium channels therefore we hypothesised that potassium channel expression in gills may be a suitable candidate to monitor the smoltification process. In support of this hypothesis, we observed increased expression of BK potassium channel mRNA in gills from S. salar under conditions of high salinity (1.2% compared to animals in FW. In this work, we designed a real-time PCR analysis in order to quantify mRNA levels of BK potassium channels in S. salar organ samples. We found differences in mRNA expression among gills, kidney and intestine. We also found a unique real-time PCR product in S. salar gills through melting curve analysis, agarose gel electrophoresis and cDNA sequencing. This PCR product showed a 98% of identity with the BK channel portion recorded by the NCBI Database and was differentially expressed in gills, kidney and intestine. This real-time PCR assay may become an important tool to study BK potassium channels expressed in the gills of S. salar and its changes during smoltification as putative new candidate to monitor this process.

  2. Hydrophobic interaction between contiguous residues in the S6 transmembrane segment acts as a stimuli integration node in the BK channel

    Science.gov (United States)

    Carrasquel-Ursulaez, Willy; Contreras, Gustavo F.; Sepúlveda, Romina V.; Aguayo, Daniel; González-Nilo, Fernando

    2015-01-01

    Large-conductance Ca2+- and voltage-activated K+ channel (BK) open probability is enhanced by depolarization, increasing Ca2+ concentration, or both. These stimuli activate modular voltage and Ca2+ sensors that are allosterically coupled to channel gating. Here, we report a point mutation of a phenylalanine (F380A) in the S6 transmembrane helix that, in the absence of internal Ca2+, profoundly hinders channel opening while showing only minor effects on the voltage sensor active–resting equilibrium. Interpretation of these results using an allosteric model suggests that the F380A mutation greatly increases the free energy difference between open and closed states and uncouples Ca2+ binding from voltage sensor activation and voltage sensor activation from channel opening. However, the presence of a bulky and more hydrophobic amino acid in the F380 position (F380W) increases the intrinsic open–closed equilibrium, weakening the coupling between both sensors with the pore domain. Based on these functional experiments and molecular dynamics simulations, we propose that F380 interacts with another S6 hydrophobic residue (L377) in contiguous subunits. This pair forms a hydrophobic ring important in determining the open–closed equilibrium and, like an integration node, participates in the communication between sensors and between the sensors and pore. Moreover, because of its effects on open probabilities, the F380A mutant can be used for detailed voltage sensor experiments in the presence of permeant cations. PMID:25548136

  3. Identification of B-K near edge x-ray absorption fine structure peaks of boron nitride thin films prepared by sputtering deposition

    International Nuclear Information System (INIS)

    Four π* resonance peaks were observed in the B-K near edge x-ray absorption fine structure spectra of boron nitride thin films prepared by magnetron sputtering. In the past, these peaks have been explained as the K-absorption of boron atoms, which are present in environment containing nitrogen vacancies, the number of which is 1-3 corresponding to the three peaks at higher photon energy. However, the authors found that there was a strong correlation between the intensities of these three peaks and that of O-K absorption after wide range scanning and simultaneous measurement of nitrogen and oxygen K-absorptions of the BN films. Therefore, the authors conclude that these three peaks at the higher energy side correspond to boron atoms bound to one-to-three oxygen atoms instead of three nitrogen atoms surrounding the boron atom in the h-BN structure. The result of the first-principles calculation with a simple cluster model supported the validity of this explanation.

  4. Biochemical characterization of the nucleic acids of some human and animal viruses

    International Nuclear Information System (INIS)

    The isolation and partial characterization of human polyomaviruses from a number of renal transplant patients is described. These isolates proved refractory to cell culture propagation by the methods used, and were thus extracted directly from large volumes of patient's urine. This approach has the advantage that the virus cannot undergo any possible genomic modification. The quantity of DNA obtained directly from urine was asually very limited. In order to produce adequate DNA for complete analysis, viral DNA was recombined with a bacterial vector and then cloned. This clone was used to prepare radioactively-labelled DNA probes for the detection of BK-specific sequences in urine isolates and in subsequent recombinants with patient material. The genomes of four rotaviruses were also studied. Experiments were performed to confirm the double-strainded RNA (dsRNA) nature of the Simian agents II genome. The difficulties in obtaining precise molecular weight values for rotavirus genome segments are also discussed. Gel systems were developed to improve on the resolution obtained in co-electrophoresis experiments. During attempts to culture Simian agents II and offal agent viruses in cell culture, it was observed that treatment of the cells and/or virus with versene-trypsin solution during infection gave a marked increase in virus yield

  5. The "ABC" of Virus-Specific T Cell Immunity in Solid Organ Transplantation.

    Science.gov (United States)

    Sester, M; Leboeuf, C; Schmidt, T; Hirsch, H H

    2016-06-01

    Transplant patients are at increased risk of viral complications due to impaired control of viral replication, resulting from HLA mismatching between graft and host and the immunosuppression needed to avert alloimmune reactions. In the past decade, quantitative viral load measurements have become widely available to identify patients at risk and to inform treatment decisions with respect to immunosuppressive drugs and antiviral therapies. Because viral loads are viewed as the result of viral replication and virus-specific immune control, virus-specific T cell monitoring has been explored to optimize management of adenovirus, BK polyomavirus and cytomegalovirus ("ABC") in transplant patients. Although most studies are descriptive using different technologies, the overall results show that the quantity and quality of virus-specific T cells inversely correlate with viral replication, whereby strong cellular immune responses are associated with containment of viral replication. The key obstacles to the introduction of assays for virus-specific T cells into clinical practice is the definition of reliable cutoffs for clinical decision making, the poor negative predictive value of some assays, and the absence of interventional trials justifying changes of antiviral treatment or immunosuppression. More clinical research is needed using optimized assays and targets before standardization and commutability can be envisaged as achieved for viral load testing. PMID:26699950

  6. Reactivation of multiple viruses in patients with sepsis.

    Directory of Open Access Journals (Sweden)

    Andrew H Walton

    Full Text Available A current controversy is whether patients with sepsis progress to an immunosuppressed state. We hypothesized that reactivation of latent viruses occurred with prolonged sepsis thereby providing evidence of clinically-relevant immunosuppression and potentially providing a means to serially-monitor patients' immune status. Secondly, if viral loads are markedly elevated, they may contribute to morbidity and mortality. This study determined if reactivation of herpesviruses, polyomaviruses, and the anellovirus TTV occurred in sepsis and correlated with severity. Serial whole blood and plasma samples from 560 critically-ill septic, 161 critically-ill non-septic, and 164 healthy age-matched patients were analyzed by quantitative-polymerase-chain-reaction for cytomegalovirus (CMV, Epstein-Barr (EBV, herpes-simplex (HSV, human herpes virus-6 (HHV-6, and TTV. Polyomaviruses BK and JC were quantitated in urine. Detectable virus was analyzed with respect to secondary fungal and opportunistic bacterial infections, ICU duration, severity of illness, and survival. Patients with protracted sepsis had markedly increased frequency of detectable virus. Cumulative viral DNA detection rates in blood were: CMV (24.2%, EBV (53.2%, HSV (14.1%, HHV-6 (10.4%, and TTV (77.5%. 42.7% of septic patients had presence of two or more viruses. The 50% detection rate for herpesviruses was 5-8 days after sepsis onset. A small subgroup of septic patients had markedly elevated viral loads (>104-106 DNA copies/ml blood for CMV, EBV, and HSV. Excluding TTV, DNAemia was uncommon in critically-ill non-septic patients and in age-matched healthy controls. Compared to septic patients without DNAemia, septic patients with viremia had increased fungal and opportunistic bacterial infections. Patients with detectable CMV in plasma had higher 90-day mortality compared to CMV-negative patients; p<0.05. Reactivation of latent viruses is common with prolonged sepsis, with frequencies similar to

  7. Viruses Infecting Reptiles

    Directory of Open Access Journals (Sweden)

    Rachel E. Marschang

    2011-11-01

    Full Text Available A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch’s postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions.

  8. Efectos sobre la salud de la contaminación de agua y alimentos por virus emergentes humanos

    Directory of Open Access Journals (Sweden)

    Sílvia Bofill-Mas

    2005-01-01

    Full Text Available El desarrollo de tecnologías moleculares aplicadas a estudios ambientales ha permitido constatar que incluso en países altamente industrializados existe una alta prevalencia de virus en el medio ambiente, lo que causa un importante impacto en la salud pública e importantes pérdidas económicas, principalmente a través de la transmisión de virus por agua y alimentos. Concentraciones significativas de virus son detectadas en las aguas vertidas al ambiente y en los biosólidos generados en plantas de tratamiento de agua residual. En este trabajo se describen las características generales de la contaminaci ón ambiental por virus, principalmente por virus emergentes, analizándose con mayor profundidad los virus de la hepatitis E (VHE y los poliomavirus humanos como los virus contaminantes ambientales de más reciente identificación en países industrializados. Se ha demostrado que existe una elevada prevalencia de los poliomavirus humanos, BK y JC, en agua residual en todos los paí- ses estudiados, lo que implica la potencial transmisión de los virus y de genes potencialmente cancerígenos por vía oral. Estudios recientes demuestran que el patrón epidemiológico de la infección por VHE en países industrializados es complejo y que una gran diversidad de cepas del VHE infecta simultáneamente a la población. El control de la contaminación viral del medio ambiente requiere la estandarización de técnicas moleculares y el desarrollo de un programa de vigilancia que permita valorar parámetros víricos y reducir la diseminación de las enfermedades establecidas y de las infecciones víricas emergentes.

  9. Testing for Human Immunodeficiency Virus

    Science.gov (United States)

    ... education Fact Sheet PFS005: Testing for Human Immunodeficiency Virus AUGUST 2015 • Reasons for Getting Tested • Who Should ... For More Information • Glossary Testing for Human Immunodeficiency Virus Human immunodeficiency virus (HIV) is the virus that ...

  10. Analysis of Virus Algorithms

    Directory of Open Access Journals (Sweden)

    Jyoti Kalyani

    2006-01-01

    Full Text Available Security of wired and wireless networks is the most challengeable in today's computer world. The aim of this study was to give brief introduction about viruses and worms, their creators and characteristics of algorithms used by viruses. Here wired and wireless network viruses are elaborated. Also viruses are compared with human immune system. On the basis of this comparison four guidelines are given to detect viruses so that more secure systems are made. While concluding this study it is found that the security is most challengeable, thus it is required to make more secure models which automatically detect viruses and prevent the system from its affect.

  11. Hepatitis Delta Virus: A Peculiar Virus

    OpenAIRE

    Carolina Alves; Cristina Branco; Celso Cunha

    2013-01-01

    The hepatitis delta virus (HDV) is distributed worldwide and related to the most severe form of viral hepatitis. HDV is a satellite RNA virus dependent on hepatitis B surface antigens to assemble its envelope and thus form new virions and propagate infection. HDV has a small 1.7 Kb genome making it the smallest known human virus. This deceivingly simple virus has unique biological features and many aspects of its life cycle remain elusive. The present review endeavors to gather the available ...

  12. Virus Infection

    Directory of Open Access Journals (Sweden)

    Hiroshi Abe

    2013-01-01

    Full Text Available Of 168 patients with chronic hepatitis B virus (HBV infection-related liver disease, 20 patients who had received 100 mg of lamivudine plus 10 mg/day of adefovir dipivoxil (ADV (ADV group and 124 patients who had received 0.5 mg/day of entecavir or 100 mg/day of lamivudine (non-ADV group for >1 year were enrolled. For comparative analyses, 19 well-matched pairs were obtained from the groups by propensity scores. At the time of enrollment, serum creatinine and phosphate concentrations were similar between the ADV and non-ADV groups; however, urinary phosphate ( and serum bone-specific alkaline phosphatase (BAP ( concentrations were significantly higher in the ADV group than in the non-ADV group. Serum BAP was significantly higher at the time of enrollment than before ADV administration in the ADV group (, although there was no significant change in serum BAP concentration in the non-ADV group. There was a significant positive correlation between the period of ADV therapy and ΔBAP (, . Serum BAP concentration increased before increase in serum creatinine concentration and was useful for early detection of adverse events and for developing adequate measures for continuing ADV for chronic HBV infection-related liver disease.

  13. Hepatitis virus panel

    Science.gov (United States)

    The hepatitis virus panel is a series of blood tests used to detect current or past infection by hepatitis A , hepatitis ... samples for more than one kind of hepatitis virus at the same time. Antibody and antigen tests ...

  14. Human Parainfluenza Viruses

    Science.gov (United States)

    ... Search The CDC Cancel Submit Search The CDC Human Parainfluenza Viruses (HPIVs) Note: Javascript is disabled or ... CDC.gov . Recommend on Facebook Tweet Share Compartir Human parainfluenza viruses (HPIVs) commonly cause respiratory illnesses in ...

  15. Tumorigenic DNA viruses

    Energy Technology Data Exchange (ETDEWEB)

    Klein, G.

    1989-01-01

    The eighth volume of Advances in Viral Oncology focuses on the three major DNA virus groups with a postulated or proven tumorigenic potential: papillomaviruses, animal hepatitis viruses, and the Epstein-Bar virus. In the opening chapters, the contributors analyze the evidence that papillomaviruses and animal hepatitis viruses are involved in tumorigenesis and describe the mechanisms that trigger virus-host cell interactions. A detailed section on the Epstein-Barr virus (EBV) - comprising more than half the book - examines the transcription and mRNA processing patterns of the virus genome; the mechanisms by which EBV infects lymphoid and epithelial cells; the immunological aspects of the virus; the actions of EBV in hosts with Acquired Immune Deficiency Syndrome; and the involvement of EBV in the etiology of Burkitt's lymphoma.

  16. Viruses and Breast Cancer

    International Nuclear Information System (INIS)

    Viruses are the accepted cause of many important cancers including cancers of the cervix and anogenital area, the liver, some lymphomas, head and neck cancers and indirectly human immunodeficiency virus associated cancers. For over 50 years, there have been serious attempts to identify viruses which may have a role in breast cancer. Despite these efforts, the establishment of conclusive evidence for such a role has been elusive. However, the development of extremely sophisticated new experimental techniques has allowed the recent development of evidence that human papilloma virus, Epstein-Barr virus, mouse mammary tumor virus and bovine leukemia virus may each have a role in the causation of human breast cancers. This is potentially good news as effective vaccines are already available to prevent infections from carcinogenic strains of human papilloma virus, which causes cancer of the uterine cervix

  17. Viruses and human cancer

    Energy Technology Data Exchange (ETDEWEB)

    Gallo, R.C.; Haseltine, W.; Klein, G.; Zur Hausen, H.

    1987-01-01

    This book contains papers on the following topics: Immunology and Epidemiology, Biology and Pathogenesis, Models of Pathogenesis and Treatment, Simian and Bovine Retroviruses, Human Papilloma Viruses, EBV and Herpesvirus, and Hepatitis B Virus.

  18. Herpes Simplex Virus (HSV)

    Science.gov (United States)

    ... rashes clinical tools newsletter | contact Share | Herpes Simplex Virus (HSV) A parent's guide to condition and treatment ... skin or mouth sores with the herpes simplex virus (HSV) is called primary herpes. This may be ...

  19. Hepatitis virus panel

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003558.htm Hepatitis virus panel To use the sharing features on this page, please enable JavaScript. The hepatitis virus panel is a series of blood tests used ...

  20. Viruses and Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lawson, James S., E-mail: james.lawson@unsw.edu.au; Heng, Benjamin [School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney (Australia)

    2010-04-30

    Viruses are the accepted cause of many important cancers including cancers of the cervix and anogenital area, the liver, some lymphomas, head and neck cancers and indirectly human immunodeficiency virus associated cancers. For over 50 years, there have been serious attempts to identify viruses which may have a role in breast cancer. Despite these efforts, the establishment of conclusive evidence for such a role has been elusive. However, the development of extremely sophisticated new experimental techniques has allowed the recent development of evidence that human papilloma virus, Epstein-Barr virus, mouse mammary tumor virus and bovine leukemia virus may each have a role in the causation of human breast cancers. This is potentially good news as effective vaccines are already available to prevent infections from carcinogenic strains of human papilloma virus, which causes cancer of the uterine cervix.

  1. Taming influenza viruses

    OpenAIRE

    Ozawa, Makoto; Kawaoka, Yoshihiro

    2011-01-01

    Plasmid-based reverse genetics systems allow the artificial generation of viruses with cloned cDNA-derived genomes. Since the establishment of such systems for influenza virus, numerous attempts have been made to tame this pathogenic agent. In particular, several types of viruses expressing foreign genes have been generated and used to further our knowledge of influenza virus replication and pathogenicity and to develop novel influenza vaccines. Here, we review these achievements and discuss ...

  2. Understanding Ebola Virus Transmission

    OpenAIRE

    Seth Judson; Joseph Prescott; Vincent Munster

    2015-01-01

    An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fil...

  3. Hepatitis D Virus Replication.

    Science.gov (United States)

    Taylor, John M

    2015-11-01

    This work reviews specific related aspects of hepatitis delta virus (HDV) reproduction, including virion structure, the RNA genome, the mode of genome replication, the delta antigens, and the assembly of HDV using the envelope proteins of its helper virus, hepatitis B virus (HBV). These topics are considered with perspectives ranging from a history of discovery through to still-unsolved problems. HDV evolution, virus entry, and associated pathogenic potential and treatment of infections are considered in other articles in this collection. PMID:26525452

  4. Lifestyles of plant viruses

    OpenAIRE

    Roossinck, Marilyn J.

    2010-01-01

    The vast majority of well-characterized eukaryotic viruses are those that cause acute or chronic infections in humans and domestic plants and animals. However, asymptomatic persistent viruses have been described in animals, and are thought to be sources for emerging acute viruses. Although not previously described in these terms, there are also many viruses of plants that maintain a persistent lifestyle. They have been largely ignored because they do not generally cause disease. The persisten...

  5. Chikungunya virus, Cameroon, 2006

    OpenAIRE

    Peyrefitte, Christophe N.; Rousset, Dominique; Pastorino, Boris A.M.; Pouillot, Regis; Bessaud, Maël; Tock, Fabienne; Mansaray, Helene; Merle, Olivier L.; Pascual, Aurelie M.; Paupy, Christophe; Vessiere, Aurelia; Imbert, Patrice; Tchendjou, Patrice; Durand, Jean-Paul; Tolou, Hugues J.

    2007-01-01

    We report the isolation of chikungunya virus from a patient during an outbreak of a denguelike syndrome in Cameroon in 2006. The virus was phylogenetically grouped in the Democratic Republic of the Congo cluster, indicating a continuous circulation of a genetically similar chikungunya virus population during 6 years in Central Africa.

  6. Computer Virus Protection

    Science.gov (United States)

    Rajala, Judith B.

    2004-01-01

    A computer virus is a program--a piece of executable code--that has the unique ability to replicate. Like biological viruses, computer viruses can spread quickly and are often difficult to eradicate. They can attach themselves to just about any type of file, and are spread by replicating and being sent from one individual to another. Simply having…

  7. What's West Nile Virus?

    Science.gov (United States)

    ... Help White House Lunch Recipes What's West Nile Virus? KidsHealth > For Kids > What's West Nile Virus? Print A A A Text Size en español ¿Qué es el Virus del Nilo Occidental? What exactly is the West ...

  8. Respiratory Syncytial Virus

    Science.gov (United States)

    ... Things to Know About Zika & Pregnancy Respiratory Syncytial Virus KidsHealth > For Parents > Respiratory Syncytial Virus Print A A A Text Size What's in ... RSV When to Call the Doctor en español Virus respiratorio sincitial About RSV Respiratory syncytial (sin-SISH- ...

  9. BOVINE VIRAL DIARRHEA VIRUSES

    Science.gov (United States)

    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...

  10. Early monitoring of the human polyomavirus BK replication and sequencing analysis in a cohort of adult kidney transplant patients treated with basiliximab

    Directory of Open Access Journals (Sweden)

    Mischitelli Monica

    2011-08-01

    Full Text Available Abstract Background Nowadays, better immunosuppressors have decreased the rates of acute rejection in kidney transplantation, but have also led to the emergence of BKV-associated nephropathy (BKVAN. Therefore, we prospectively investigated BKV load in plasma and urine samples in a cohort of kidney transplants, receiving basiliximab combined with a mycophenolate mofetil-based triple immunotherapy, to evaluate the difference between BKV replication during the first 3 months post-transplantation, characterized by the non-depleting action of basiliximab, versus the second 3 months, in which the maintenance therapy acts alone. We also performed sequencing analysis to assess whether a particular BKV subtype/subgroup or transcriptional control region (TCR variants were present. Methods We monitored BK viruria and viremia by quantitative polymerase chain reaction (Q-PCR at 12 hours (Tx, 1 (T1, 3 (T2 and 6 (T3 months post-transplantation among 60 kidney transplant patients. Sequencing analysis was performed by nested-PCR with specific primers for TCR and VP1 regions. Data were statistically analyzed using χ2 test and Student's t-test. Results BKV was detected at Tx in 4/60 urine and in 16/60 plasma, with median viral loads of 3,70 log GEq/mL and 3,79 log GEq/mL, respectively, followed by a significant increase of both BKV-positive transplants (32/60 and median values of viruria (5,78 log GEq/mL and viremia (4,52 log GEq/mL at T2. Conversely, a significantly decrease of patients with viruria and viremia (17/60 was observed at T3, together with a reduction of the median urinary and plasma viral loads (4,09 log GEq/mL and 4,00 log GEq/mL, respectively. BKV TCR sequence analysis always showed the presence of archetypal sequences, with a few single-nucleotide substitutions and one nucleotide insertion that, interestingly, were all representative of the particular subtypes/subgroups we identified by VP1 sequencing analysis: I/b-2 and IV/c-2. Conclusions Our

  11. Development of a reverse genetics system for epizootic hemorrhagic disease virus and evaluation of novel strains containing duplicative gene rearrangements.

    Science.gov (United States)

    Yang, Tao; Zhang, Jikai; Xu, Qingyuan; Sun, Encheng; Li, Junping; Lv, Shuang; Feng, Yufei; Zhang, Qin; Wang, Haixiu; Wang, Hua; Wu, Donglai

    2015-09-01

    Epizootic haemorrhagic disease is a non-contagious infectious viral disease of wild and domestic ruminants caused by epizootic hemorrhagic disease virus (EHDV). EHDV belongs to the genus Orbivirus within the family Reoviridae and is transmitted by insects of the genus Culicoides. The impact of epizootic haemorrhagic disease is underscored by its designation as a notifiable disease by the Office International des Epizooties. The EHDV genome consists of 10 linear dsRNA segments (Seg1-Seg10). Until now, no reverse genetics system (RGS) has been developed to generate replication-competent EHDV entirely from cloned cDNA, hampering detailed functional analyses of EHDV biology. Here, we report the generation of viable EHDV entirely from cloned cDNAs. A replication-competent EHDV-2 (Ibaraki BK13 strain) virus incorporating a marker mutation was rescued by transfection of BHK-21 cells with expression plasmids and in vitro synthesized RNA transcripts. Using this RGS, two additional modified EHDV-2 viruses were also generated: one that contained a duplex concatemeric Seg9 gene and another that contained a duplex concatemeric Seg10 gene. The modified EHDV-2 with a duplex Seg9 gene was genetically stable during serial passage in BHK-21 cells. In contrast, the modified EHDV-2 with a duplex Seg10 gene was unstable during serial passage, but displayed enhanced replication kinetics in vitro when compared with the WT virus. This RGS provides a new platform for the investigation of EHDV replication, pathogenesis and novel EHDV vaccines. PMID:25998915

  12. Understanding Ebola Virus Transmission

    Directory of Open Access Journals (Sweden)

    Seth Judson

    2015-02-01

    Full Text Available An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fill these voids in our knowledge about the transmission of Ebola virus.

  13. Viruses of asparagus.

    Science.gov (United States)

    Tomassoli, Laura; Tiberini, Antonio; Vetten, Heinrich-Josef

    2012-01-01

    The current knowledge on viruses infecting asparagus (Asparagus officinalis) is reviewed. Over half a century, nine virus species belonging to the genera Ilarvirus, Cucumovirus, Nepovirus, Tobamovirus, Potexvirus, and Potyvirus have been found in this crop. The potyvirus Asparagus virus 1 (AV1) and the ilarvirus Asparagus virus 2 (AV2) are widespread and negatively affect the economic life of asparagus crops reducing yield and increasing the susceptibility to biotic and abiotic stress. The main properties and epidemiology of AV1 and AV2 as well as diagnostic techniques for their detection and identification are described. Minor viruses and control are briefly outlined. PMID:22682173

  14. Online identification of viruses.

    Science.gov (United States)

    Kolaskar, A S; Naik, P S

    2000-06-01

    A computerized animal virus information system is developed in the Sequence Retrieval System (SRS) format. This database is available on the Word Wide Web (WWW) at the site http://bioinfo.ernet.in/www/avis/avis++ +.html. The database has been used to generate large number of identification matrices for each family. The software is developed in C. Unix shell scripts and Hypertext Marked-up Language (HTML) to assign the family to an unknown virus deterministically and to identify the virus probabilistically. It has been shown that such web based virus identification approach provides results with high confidence in those cases where identification matrix uses large number of independent characters. Protein sequence data for animal viruses have been analyzed and oligopeptides specific to each virus family and also specific to each virus species are identified for several viruses. These peptides thus could be used to identify the virus and to assign the virus family with high confidence showing the usefulness of sequence data in virus identification. PMID:10917875

  15. Protoplasts and plant viruses

    International Nuclear Information System (INIS)

    The use of protoplasts in the study of plant viruses has attracted considerable attention since its inception in the late 1960s. This article is an attempt to assess the current status of protoplasts (primarily) and all cell cultures (in some instances) in studies of virus infection, virus replication, cytopathology, cross-protection, virus resistance, and the use of in vitro methods and genetic engineering to recover virus-resistant plants. These areas of study proved difficult to do entirely with whole plants or plant parts. However, because protoplasts could be synchronously infected with virus, they provided a valuable alternative means of following biochemical and cytological events in relation to the virus growth cycle in a more precise manner than previously possible

  16. RNA Viruses Infecting Pest Insects

    Science.gov (United States)

    RNA viruses are viruses whose genetic material is ribonucleic acid (RNA). RNA viruses may be double or single-stranded based on the type of RNA they contain. Single-stranded RNA viruses can be further grouped into negative sense or positive-sense viruses according to the polarity of their RNA. Fur...

  17. High diversity of human polyomaviruses in environmental and clinical samples in Argentina: Detection of JC, BK, Merkel-cell, Malawi, and human 6 and 7 polyomaviruses.

    Science.gov (United States)

    Torres, Carolina; Barrios, Melina Elizabeth; Cammarata, Robertina Viviana; Cisterna, Daniel Marcelo; Estrada, Tatiana; Martini Novas, Sergio; Cahn, Pedro; Blanco Fernández, María Dolores; Mbayed, Viviana Andrea

    2016-01-15

    New human polyomaviruses have been recently described. The aim of this work was to detect and characterize human polyomaviruses circulating in Argentina by recovering viruses from environmental and sewage samples and evaluating their potential role as viral indicators of human waste contamination. Analysis was performed in a wider context including viruses from clinical samples from an immunocompromised population. River water and sewage samples were analyzed as a strategy to study the molecular epidemiology of viruses excreted by millions of people. Samples belonged to the Matanza-Riachuelo River (2005-2006: n=25 and 2012: n=20) and sewage from Buenos Aires city and suburbs (2011 and 2013: n=24). Viral detection was performed by PCR and the amplified viral genomes were characterized by phylogenetic analysis. Polyomaviruses were detected in 95.8% of sewage samples, identifying BKPyV (87.5%), JCPyV (83.3%), MCPyV (8.3%) and HPyV6 (8.3%). Besides, one sample collected in 2009 resulted positive for HPyV7. In 2005-2006, polyomaviruses were detected in 84.0% of river water samples, with the highest detection for MCPyV (52.0%), followed by BKPyV (44.0%), JCPyV (20.0%) and MWPyV (4.0%). In 2012, polyomaviruses were detected in 85.0% of river samples, finding JCPyV (85.0%), BKPyV (75.0%), MCPyV (25.0%) and HPyV6 (25.0%). Also, polyomaviruses, including JCPyV, BKPyV and MCPyV, were detected in 63.2% of urine samples from patients infected with HIV (n=19). Characterization indicated the coexistence of different genotypes and variants for each virus, particularly in sewage. MCPyV sequences (the only sequences from Argentina) formed a monophyletic group with the single sequence available for South America (French Guiana). The high level of detection and viral diversity found by environmental surveillance, which involved the characterization of viruses not previously described in South America, reinforces the usefulness of this approach to monitor viral contamination and

  18. Cloning, expression in Pichia pastoris, and characterization of a thermostable GH5 mannan endo-1,4-β-mannosidase from Aspergillus niger BK01

    Directory of Open Access Journals (Sweden)

    Sigoillot Jean-Claude

    2009-11-01

    Full Text Available Abstract Background Mannans are key components of lignocellulose present in the hemicellulosic fraction of plant primary cell walls. Mannan endo-1,4-β-mannosidases (1,4-β-D-mannanases catalyze the random hydrolysis of β-1,4-mannosidic linkages in the main chain of β-mannans. Biodegradation of β-mannans by the action of thermostable mannan endo-1,4-β-mannosidase offers significant technical advantages in biotechnological industrial applications, i.e. delignification of kraft pulps or the pretreatment of lignocellulosic biomass rich in mannan for the production of second generation biofuels, as well as for applications in oil and gas well stimulation, extraction of vegetable oils and coffee beans, and the production of value-added products such as prebiotic manno-oligosaccharides (MOS. Results A gene encoding mannan endo-1,4-β-mannosidase or 1,4-β-D-mannan mannanohydrolase (E.C. 3.2.1.78, commonly termed β-mannanase, from Aspergillus niger BK01, which belongs to glycosyl hydrolase family 5 (GH5, was cloned and successfully expressed heterologously (up to 243 μg of active recombinant protein per mL in Pichia pastoris. The enzyme was secreted by P. pastoris and could be collected from the culture supernatant. The purified enzyme appeared glycosylated as a single band on SDS-PAGE with a molecular mass of approximately 53 kDa. The recombinant β-mannanase is highly thermostable with a half-life time of approximately 56 h at 70°C and pH 4.0. The optimal temperature (10-min assay and pH value for activity are 80°C and pH 4.5, respectively. The enzyme is not only active towards structurally different mannans but also exhibits low activity towards birchwood xylan. Apparent Km values of the enzyme for konjac glucomannan (low viscosity, locust bean gum galactomannan, carob galactomannan (low viscosity, and 1,4-β-D-mannan (from carob are 0.6 mg mL-1, 2.0 mg mL-1, 2.2 mg mL-1 and 1.5 mg mL-1, respectively, while the kcat values for these

  19. Constructing computer virus phylogenies

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, L.A. [Warwick Univ., Coventry (United Kingdom) Dept. of Computer Science; Goldberg, P.W. [Aston Univ., Birmingham (United Kingdom) Dept. of Applied Mathematics; Phillips, C.A. [Sandia National Labs., Albuquerque, NM (United States); Sorkin, G.B. [International Business Machines Corp., Yorktown Heights, NY (United States). Thomas J. Watson Research Center

    1996-03-01

    There has been much recent algorithmic work on the problem of reconstructing the evolutionary history of biological species. Computer virus specialists are interested in finding the evolutionary history of computer viruses--a virus is often written using code fragments from one or more other viruses, which are its immediate ancestors. A phylogeny for a collection of computer viruses is a directed acyclic graph whose nodes are the viruses and whose edges map ancestors to descendants and satisfy the property that each code fragment is ``invented`` only once. To provide a simple explanation for the data, we consider the problem of constructing such a phylogeny with a minimal number of edges. In general, this optimization problem cannot be solved in quasi-polynomial time unless NQP=QP; we present positive and negative results for associated approximated problems. When tree solutions exist, they can be constructed and randomly sampled in polynomial time.

  20. Sulfated polysaccharides are potent and selective inhibitors of various enveloped viruses, including herpes simplex virus, cytomegalovirus, vesicular stomatitis virus, and human immunodeficiency virus.

    OpenAIRE

    Baba, M.; Snoeck, R; Pauwels, R; De Clercq, E

    1988-01-01

    Several sulfated polysaccharides (dextran sulfate, pentosan polysulfate, fucoidan, and carrageenans) proved to be potent inhibitors for herpes simplex virus, human cytomegalovirus, vesicular stomatitis virus, Sindbis virus, and human immunodeficiency virus. They were moderately inhibitory to vaccinia virus but not inhibitory to adenovirus, coxsackievirus, poliovirus, parainfluenza virus, and reovirus. These results indicate that, with the exception of parainfluenza virus, enveloped viruses ar...

  1. Detection of polyomavirus simian virus 40 tumor antigen DNA in AIDS-related systemic non-Hodgkin lymphoma

    Science.gov (United States)

    Vilchez, Regis A.; Lednicky, John A.; Halvorson, Steven J.; White, Zoe S.; Kozinetz, Claudia A.; Butel, Janet S.

    2002-01-01

    Systemic non-Hodgkin lymphoma (S-NHL) is a common malignancy during HIV infection, and it is hypothesized that infectious agents may be involved in the etiology. Epstein-Barr virus DNA is found in pathogenesis. We analyzed AIDS-related S-NHL samples, NHL samples from HIV-negative patients, peripheral blood leukocytes from HIV-infected and -uninfected patients without NHL, and lymph nodes without tumors from HIV-infected patients. Specimens were examined by polymerase chain reaction analysis with use of primers specific for an N-terminal region of the oncoprotein large tumor antigen ( T-ag ) gene conserved among all three polyomaviruses (simian virus 40 [SV40], JC virus, and BK virus). Polyomavirus T-ag DNA sequences, proven to be SV40-specific, were detected more frequently in AIDS-related S-NHL samples (6 of 26) than in peripheral blood leukocytes from HIV-infected patients (6 of 26 vs. 0 of 69; p =.0001), NHL samples from HIV-negative patients (6 of 26 vs. 0 of 10; p =.09), or lymph nodes (6 of 26 vs. 0 of 7; p =.16). Sequences of C-terminal T-ag DNA from SV40 were amplified from two AIDS-related S-NHL samples. Epstein-Barr virus DNA sequences were detected in 38% (10 of 26) AIDS-related S-NHL samples, 50% (5 of 10) HIV-negative S-NHL samples, and 57% (4 of 7) lymph nodes. None of the S-NHL samples were positive for both Epstein-Barr virus DNA and SV40 DNA. Further studies of the possible role of SV40 in the pathogenesis of S-NHL are warranted.

  2. Zika virus - an overview.

    Science.gov (United States)

    Zanluca, Camila; Dos Santos, Claudia Nunes Duarte

    2016-05-01

    Zika virus (ZIKV) is currently one of the most important emerging viruses in the world. Recently, it has caused outbreaks and epidemics, and has been associated with severe clinical manifestations and congenital malformations. However to date, little is known about the pathogenicity of the virus and the consequences of ZIKV infection. In this paper, we provide an overview of the current knowledge on ZIKV. PMID:26993028

  3. The Influenza Virus Enigma

    OpenAIRE

    Salomon, Rachelle; Webster, Robert G.

    2009-01-01

    Both seasonal and pandemic influenza continue to challenge both scientists and clinicians. Drug-resistant H1N1 influenza viruses have dominated the 2009 flu season, and the H5N1 avian influenza virus continues to kill both people and poultry in Eurasia. Here, we discuss the pathogenesis and transmissibility of influenza viruses and we emphasize the need to find better predictors of both seasonal and potentially pandemic influenza.

  4. Endocytosis of influenza viruses

    OpenAIRE

    Lakadamyali, Melike; Rust, Michael J.; Zhuang, Xiaowei

    2004-01-01

    Receptor-mediated endocytosis is known to play an important role in the entry of many viruses into host cells. However, the exact internalization mechanism has, until recently, remained poorly understood for many medically important viruses, including influenza. Developments in real-time imaging of single viruses as well as the use of dominant negative mutants to selectively block specific endocytic pathways, have improved our understanding of the influenza infection process.

  5. Filamentous influenza viruses

    OpenAIRE

    Dadonaite, Bernadeta; Vijyakrishnan, Swetha; Fodor, Ervin; Bhella, David; Hutchinson, Edward C.

    2016-01-01

    Clinical isolates of influenza virus produce pleomorphic virus particles, including extremely long filamentous virions. In contrast, strains of influenza that have adapted to laboratory growth typically produce only spherical virions. As a result, the filamentous phenotype has been overlooked in most influenza virus research. Recent advances in imaging and improved animal models have highlighted the distinct structure and functional relevance of filamentous virions. In this review we summaris...

  6. The virus of management

    OpenAIRE

    Kjær, Peter; Frankel, Christian

    2004-01-01

    The virus metaphor may be used in studies of management knowledge not only as a way of describing diffusion processes but also as a way of thinking about viral elements of knowledge production. In the present article, organizational viruses are viewed as ensembles of basic distinctions that are constitutive of concrete bodies of knowledge and which form mutable engines of organizational self-descriptions. Organizational viruses, we contend, are both characterized by stability i...

  7. Viruses in Turing's Garden

    OpenAIRE

    Marion, Jean-Yves

    2012-01-01

    Cohen and his supervisor Adleman defined a virus as follows: "A virus is a program that is able to infect other programs by modifying them to include a possibly evolved copy to itself". This definition seems to be well accepted by the computer security community as a foundational definition. Thus, a virus is a self-replicating program, whose offspring may be a mutation of the original program. Viruses thrive in our computers, which are based on Turing's model of computation. We discuss the fu...

  8. Residual viruses in pork products.

    Science.gov (United States)

    McKercher, P D; Hess, W R; Hamdy, F

    1978-01-01

    Partly cooked canned hams and dried pepperoni and salami sausages were prepared from the carcasses of pigs infected with African swine fever virus and pigs infected with hog cholera virus. Virus was not recovered from the partly cooked canned hams; however, virus was recovered in the hams before heating in both instances. Both African swine fever virus and hog cholera virus were recovered from the dried salami and pepperoni sausages, but not after the required curing period. PMID:564162

  9. FAQ: General Questions about West Nile Virus

    Science.gov (United States)

    ... Public Service Videos General Questions About West Nile Virus Recommend on Facebook Tweet Share Compartir On this ... West Nile virus cases? What is West Nile virus? West Nile virus is an arthropod-borne virus ( ...

  10. Viral Haemorrhagic Septicaemia Virus

    DEFF Research Database (Denmark)

    Olesen, Niels Jørgen; Skall, Helle Frank

    This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus.......This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus....

  11. INFLUENZA VIRUS IN POULTRY

    Science.gov (United States)

    Avian influenza virus (AIV) is normally found in wild birds, particularly in ducks and shorebirds, where it does not cause any perceptible clinical disease. However, poultry, including chickens and turkeys, are not normal hosts for avian influenza, but if the virus is introduced it can result in mi...

  12. Zika Virus and Pregnancy.

    Science.gov (United States)

    Stagg, Denise; Hurst, Helen M

    2016-01-01

    Recent outbreaks of Zika virus and reports linking infection in pregnant women with microcephaly in newborns have caused concern worldwide. Information has been evolving rapidly. Nurses and other clinicians, especially those who work with women of childbearing age, play a pivotal role in disseminating accurate information and identifying potential cases of Zika virus infection. PMID:27287356

  13. Papaya ringspot virus (Potyviridae)

    Science.gov (United States)

    Papaya ringspot virus, a member of the family Potyviridae, is single stranded RNA plant virus with a monocistronic genome of about 10,326 nucleotides that is expressed via a large polyprotein subsequently cleaved into functional proteins. It causes severe damage on cucurbit crops such as squash and...

  14. Viral Haemorrhagic Septicaemia Virus

    DEFF Research Database (Denmark)

    Olesen, Niels Jørgen; Skall, Helle Frank

    2013-01-01

    This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus.......This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus....

  15. Rift Valley Fever Virus

    Science.gov (United States)

    Rift Valley fever virus (RVFV) is a mosquito-transmitted virus or arbovirus that is endemic in sub-Saharan Africa. In the last decade, Rift Valley fever (RVF) outbreaks have resulted in loss of human and animal life, as well as had significant economic impact. The disease in livestock is primarily a...

  16. Pornografinio turinio produkcijos gaminimas, platinimas ir viešas demonstravimas. Atsakomybė už tai LR BK ir kitų valstybių įstatymuose

    OpenAIRE

    Supranavičiūtė, Joana

    2011-01-01

    Lietuvos Respublikos Baudžiamojo kodekso 309 straipsnis “Disponavimas pornografinio turinio dalykais“ nustato baudžiamąją atsakomybę už pornografijos gaminimą, platinimą, reklamavimą ir viešą demonstravimą. Straipsnis skiria pornografiją į pilnamečių asmenų ir vaikų pornografiją. Nors ši veika yra kriminalizuota, praktikoje LR BK 309 straipsnis taikomas retai dėl keblumų, kylančių internetinėje erdvėje – fiziniai ir juridiniai asmenys gali lengvai išvengti baudžiamosios atsakomybės. Atsižv...

  17. Computer Viruses: Pathology and Detection.

    Science.gov (United States)

    Maxwell, John R.; Lamon, William E.

    1992-01-01

    Explains how computer viruses were originally created, how a computer can become infected by a virus, how viruses operate, symptoms that indicate a computer is infected, how to detect and remove viruses, and how to prevent a reinfection. A sidebar lists eight antivirus resources. (four references) (LRW)

  18. Postmortem Stability of Ebola Virus

    OpenAIRE

    Prescott, Joseph; Bushmaker, Trenton; Fischer, Robert; Miazgowicz, Kerri; Judson, Seth; Vincent J. Munster

    2015-01-01

    The ongoing Ebola virus outbreak in West Africa has highlighted questions regarding stability of the virus and detection of RNA from corpses. We used Ebola virus–infected macaques to model humans who died of Ebola virus disease. Viable virus was isolated

  19. Interaction between Simian Virus 40 Major Capsid Protein VP1 and Cell Surface Ganglioside GM1 Triggers Vacuole Formation

    Science.gov (United States)

    Luo, Yong; Motamedi, Nasim; Magaldi, Thomas G.; Gee, Gretchen V.; Atwood, Walter J.

    2016-01-01

    ABSTRACT Simian virus 40 (SV40), a polyomavirus that has served as an important model to understand many aspects of biology, induces dramatic cytoplasmic vacuolization late during productive infection of monkey host cells. Although this activity led to the discovery of the virus in 1960, the mechanism of vacuolization is still not known. Pentamers of the major SV40 capsid protein VP1 bind to the ganglioside GM1, which serves as the cellular receptor for the virus. In this report, we show that binding of VP1 to cell surface GM1 plays a key role in SV40 infection-induced vacuolization. We previously showed that SV40 VP1 mutants defective for GM1 binding fail to induce vacuolization, even though they replicate efficiently. Here, we show that interfering with GM1-VP1 binding by knockdown of GM1 after infection is established abrogates vacuolization by wild-type SV40. Vacuole formation during permissive infection requires efficient virus release, and conditioned medium harvested late during SV40 infection rapidly induces vacuoles in a VP1- and GM1-dependent fashion. Furthermore, vacuolization can also be induced by a nonreplicating SV40 pseudovirus in a GM1-dependent manner, and a mutation in BK pseudovirus VP1 that generates GM1 binding confers vacuole-inducing activity. Vacuolization can also be triggered by purified pentamers of wild-type SV40 VP1, but not by GM1 binding-defective pentamers or by intracellular expression of VP1. These results demonstrate that SV40 infection-induced vacuolization is caused by the binding of released progeny viruses to GM1, thereby identifying the molecular trigger for the activity that led to the discovery of SV40. PMID:27006465

  20. Hepatitis A virus antibody

    International Nuclear Information System (INIS)

    A description is presented of a radioimmunoassay designed to prove the presence of the antibody against the hepatitis A virus (HA Ab, anti-Ha) using an Abbott HAVAB set. This proof as well as the proof of the antibody against the nucleus of the hepatitis B virus is based on competition between a normal antibody against hepatitis A virus and a 125I-labelled antibody for the binding sites of a specific antigen spread all over the surface of a tiny ball; this is then indirect proof of the antibody under investigation. The method is described of reading the results from the number of impulses per 60 seconds: the higher the titre of the antibody against the hepatitis A virus in the serum examined, the lower the activity of the specimen concerned. The rate is reported of incidence of the antibody against the hepatitis A virus in a total of 68 convalescents after hepatitis A; the antibody was found in 94.1%. The immunoglobulin made from the convalescents' plasma showed the presence of antibodies in dilutions as high as 1:250 000 while the comparable ratio for normal immunoglobulin Norga was only 1:2500. Differences are discussed in the time incidence of the antibodies against the hepatitis A virus, the antibodies against the surface antigen of hepatitis B, and the antibody against the nucleus of the hepatitis V virus. (author)

  1. Archaeal virus-host interactions

    OpenAIRE

    Quax, T.E.F.

    2013-01-01

      The work presented in this thesis provides novel insights in several aspects of the molecular biology of archaea, bacteria and their viruses. Three fundamentally different groups of viruses are associated with the three domains of life. Archaeal viruses are characterized by a particularly high morphological and genetic diversity. Some archaeal viruses, such as Sulfolobus islandicus rod-shaped virus 2 (SIRV2), have quite remarkable infection cycles. As described in Chapter 1, infection ...

  2. Viruses in reptiles

    Directory of Open Access Journals (Sweden)

    Ariel Ellen

    2011-09-01

    Full Text Available Abstract The etiology of reptilian viral diseases can be attributed to a wide range of viruses occurring across different genera and families. Thirty to forty years ago, studies of viruses in reptiles focused mainly on the zoonotic potential of arboviruses in reptiles and much effort went into surveys and challenge trials of a range of reptiles with eastern and western equine encephalitis as well as Japanese encephalitis viruses. In the past decade, outbreaks of infection with West Nile virus in human populations and in farmed alligators in the USA has seen the research emphasis placed on the issue of reptiles, particularly crocodiles and alligators, being susceptible to, and reservoirs for, this serious zoonotic disease. Although there are many recognised reptilian viruses, the evidence for those being primary pathogens is relatively limited. Transmission studies establishing pathogenicity and cofactors are likewise scarce, possibly due to the relatively low commercial importance of reptiles, difficulties with the availability of animals and permits for statistically sound experiments, difficulties with housing of reptiles in an experimental setting or the inability to propagate some viruses in cell culture to sufficient titres for transmission studies. Viruses as causes of direct loss of threatened species, such as the chelonid fibropapilloma associated herpesvirus and ranaviruses in farmed and wild tortoises and turtles, have re-focused attention back to the characterisation of the viruses as well as diagnosis and pathogenesis in the host itself. 1. Introduction 2. Methods for working with reptilian viruses 3. Reptilian viruses described by virus families 3.1. Herpesviridae 3.2. Iridoviridae 3.2.1 Ranavirus 3.2.2 Erythrocytic virus 3.2.3 Iridovirus 3.3. Poxviridae 3.4. Adenoviridae 3.5. Papillomaviridae 3.6. Parvoviridae 3.7. Reoviridae 3.8. Retroviridae and inclusion body disease of Boid snakes 3.9. Arboviruses 3.9.1. Flaviviridae 3

  3. VHS virus - present situation

    DEFF Research Database (Denmark)

    Olesen, Niels Jørgen; Skall, Helle Frank

    worldwide distribution of the disease will be given. Virus evolution: Recent studies indicate that only a few amino acid changes in the structural proteins of VHSV can change the virulence patterns significantly, thereby coming closer to assessing the risk of none to low virulent viruses becoming high...... virulent. Virulence factors both depend on the ability of VHSV to enter a cell and on the speed and efficiency of virus replication in the cells. Apparently the viral nucleocapsid protein plays a very important role for the later and seems to be the target for determination of a virulence marker....

  4. VHS virus - present situation

    DEFF Research Database (Denmark)

    Skall, Helle Frank; Olesen, Niels Jørgen

    2015-01-01

    worldwide distribution of the disease will be given. Virus evolution: Recent studies indicate that only a few amino acid changes in the structural proteins of VHSV can change the virulence patterns significantly, thereby coming closer to assessing the risk of none to low virulent viruses becoming high...... virulent. Virulence factors both depend on the ability of VHSV to enter a cell and on the speed and efficiencyof virus replication in the cells. Apparently the viral nucleocapsid protein plays a very important role for the later and seems to be the target for determination of a virulence marker....

  5. Zika Virus Fact Sheet

    Science.gov (United States)

    ... medical care and advice. There is currently no vaccine available. Prevention Mosquito bites Protection against mosquito bites is a key measure to prevent Zika virus infection. This can be done by wearing ...

  6. Ebola (Ebola Virus Disease)

    Science.gov (United States)

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... Tweet Share Compartir CDC's Ongoing Work to Contain Ebola in West Africa The Road to Zero: CDC’s ...

  7. Hepatitis G virus

    Institute of Scientific and Technical Information of China (English)

    Vasiliy Ivanovich Reshetnyak; Tatiana Igorevna Karlovich; Ljudmila Urievna Ilchenko

    2008-01-01

    A number of new hepatitis viruses (G,TT,SEN) were discovered late in the past century.We review the data available in the literature and our own findings suggesting that the new hepatitis G virus (HGV),disclosed in the late 1990s,has been rather well studied.Analysis of many studies dealing with HGV mainly suggests the lymphotropicity of this virus.HGV or GBV-C has been ascertained to influence course and prognosis in the HIV-infected patient.Until now,the frequent presence of GBV-C in coinfections,hematological diseases,and biliary pathology gives no grounds to determine it as an "accidental tourist" that is of no significance.The similarity in properties of GBV-C and hepatitis C virus (HCV) offers the possibility of using HGV,and its induced experimental infection,as a model to study hepatitis C and to develop a hepatitis C vaccine.

  8. [Zika, a neurotropic virus?].

    Science.gov (United States)

    Del Carpio-Orantes, Luis

    2016-01-01

    In this paper, the neurotropism potential Zika virus is discussed, by comparison with viruses both RNA and DNA are neurotropic known, also it is said that compared with the new viruses that have affected the Americas, as the chikungunya, Zika has shown great affinity by brain tissue, manifested by a high incidence of acute neurological conditions, such as Guillain-Barré syndrome, among others, as well as the reported incidence of microcephaly that is abnormally high compared with the previous incidence, which, in a stillborn subject necropsied significant alterations demonstrated in brain tissue, identifying viral material and live virus in the fetoplacental complex, and demonstrating the impact both white matter and gray matter as well as basal ganglia, corpus callosum, ventricles and spinal cord, which could explain the microcephaly that concerns him. Although not a direct cause-effect relationship is demonstrated, however current evidence supports that relationship, hoping to be supported scientifically. PMID:27197113

  9. Simian Immunodeficiency Virus Retropepsin

    Czech Academy of Sciences Publication Activity Database

    Konvalinka, Jan; Kräusslich, H. G.

    Amsterdam: Academic Press, 2013 - (Salvesen, G.), s. 204-207 ISBN 978-0-12-382219-2 Institutional support: RVO:61388963 Keywords : simian immunodeficiency virus * retropepsin * protease Subject RIV: CE - Biochemistry

  10. Ebola Virus Disease

    Science.gov (United States)

    ... long as their blood contains the virus. Sexual transmission More surveillance data and research are needed on the risks of sexual transmission, and particularly on the prevalence of viable and ...

  11. Zika Virus Outside Africa

    OpenAIRE

    Hayes, Edward B

    2009-01-01

    Zika virus (ZIKV) is a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis viruses. In 2007 ZIKV caused an outbreak of relatively mild disease characterized by rash, arthralgia, and conjunctivitis on Yap Island in the southwestern Pacific Ocean. This was the first time that ZIKV was detected outside of Africa and Asia. The history, transmission dynamics, virology, and clinical manifestations of ZIKV disease are discussed, along with the possibility for diagnostic ...

  12. Simian Varicella Virus Pathogenesis

    OpenAIRE

    Mahalingam, Ravi; Messaoudi, Ilhem; Gilden, Don

    2010-01-01

    Because varicella zoster virus (VZV) is an exclusively human pathogen, the development of an animal model is necessary to study pathogenesis, latency, and reactivation. The pathological, virological, and immunological features of simian varicella virus (SVV) infection in nonhuman primates are similar to those of VZV infection in humans. Both natural infection of cynomolgus and African green monkeys as well as intrabronchial inoculation of rhesus macaques with SVV provide the most useful model...

  13. Respiratory Syncytial Virus (RSV)

    Centers for Disease Control (CDC) Podcasts

    2013-02-04

    Respiratory Syncytial Virus, or RSV, causes cold-like symptoms but can be serious for infants and older adults. In this podcast, CDC’s Dr. Eileen Schneider discusses this common virus and offers tips to prevent its spread.  Created: 2/4/2013 by National Center for Immunization and Respiratory Diseases (NCIRD), Division of Viral Diseases (DVD).   Date Released: 2/13/2013.

  14. How do Viruses Attack Anti-Virus Programs

    OpenAIRE

    Mishra, Umakant

    2013-01-01

    As the anti-viruses run in a trusted kernel level any loophole in the anti-virus program can enable attackers to take full control over the computer system and steal data or do serious damages. Hence the anti-virus engines must be developed with proper security in mind. The ant-virus should be able to any type of specially created executable files, compression packages or documents that are intentionally created to exploit the anti-virus weakness. Viruses are present in almost every system ev...

  15. Virus templated metallic nanoparticles

    Science.gov (United States)

    Aljabali, Alaa A. A.; Barclay, J. Elaine; Lomonossoff, George P.; Evans, David J.

    2010-12-01

    Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron.Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron. Electronic supplementary information (ESI) available: Additional experimental detail, agarose gel electrophoresis results, energy dispersive X-ray spectra, ζ-potential measurements, dynamic light scattering data, nanoparticle tracking analysis and an atomic force microscopy image of Ni-CPMV. See DOI: 10.1039/c0nr00525h

  16. Avian Influenza A Virus Infections in Humans

    Science.gov (United States)

    ... Past Newsletters Avian Influenza A Virus Infections in Humans Language: English Español Recommend on Facebook Tweet ... A Viruses Avian Influenza A Virus Infections in Humans Although avian influenza A viruses usually do not ...

  17. A New Definition of Virus

    Institute of Scientific and Technical Information of China (English)

    HE Hongjun; CAO Sihua; LUO Li; FENG Tao; PAN Li; ZOU Zhiji

    2006-01-01

    Security experts have not formally defined the distinction between viruses and normal programs. The paper takes user's intension as the criteria for malice, gives a formal definition of viruses that aim at stealing or destroying files, and proposes an algorithm to detect virus correctly. Compared with traditional definitions, this new definition is easy to understand, covers more malwares, adapts development of virus technology, and defines virus on the spot. The paper has also analyzed more than 250 real viruses and finds that they are all in the domain of the new definition, this implies that the new definition has great practical significance.

  18. [Zika virus infection during pregnancy].

    Science.gov (United States)

    Picone, O; Vauloup-Fellous, C; D'Ortenzio, E; Huissoud, C; Carles, G; Benachi, A; Faye, A; Luton, D; Paty, M-C; Ayoubi, J-M; Yazdanpanah, Y; Mandelbrot, L; Matheron, S

    2016-05-01

    A Zika virus epidemic is currently ongoing in the Americas. This virus is linked to congenital infections with potential severe neurodevelopmental dysfunction. However, incidence of fetal infection and whether this virus is responsible of other fetal complications are still unknown. National and international public health authorities recommend caution and several prevention measures. Declaration of Zika virus infection is now mandatory in France. Given the available knowledge on Zika virus, we suggest here a review of the current recommendations for management of pregnancy in case of suspicious or infection by Zika virus in a pregnant woman. PMID:27079865

  19. Hepatitis viruses: Changing patterns of human disease

    OpenAIRE

    Purcell, R H

    1994-01-01

    Viral hepatitis is a disease of antiquity, but evidence for more than one etiologic agent has been recognized only since the 1940s, when two viruses (hepatitis A virus and hepatitis B virus) were thought to account for all disease. In the past 20 years, three additional hepatitis agents (hepatitis C virus, hepatitis D virus, and hepatitis E virus) have been discovered, and there is evidence for at least one additional virus. Each of the five recognized hepatitis viruses belongs to a different...

  20. Molecular epidemiology of respiratory viruses in virus-induced asthma

    OpenAIRE

    HiroyukiTsukagoshi; TaiseiIshioka

    2013-01-01

    Acute respiratory illness (ARI) due to various viruses is not only the most common cause of upper respiratory infection in humans but is also a major cause of morbidity and mortality, leading to diseases such as bronchiolitis and pneumonia. Previous studies have shown that respiratory syncytial virus (RSV), human rhinovirus (HRV), human metapneumovirus (HMPV), human parainfluenza virus (HPIV), and human enterovirus (HEV) infections may be associated with virus-induced asthma. For example, it ...

  1. Recombinant Vaccinia Virus: Immunization against Multiple Pathogens

    Science.gov (United States)

    Perkus, Marion E.; Piccini, Antonia; Lipinskas, Bernard R.; Paoletti, Enzo

    1985-09-01

    The coding sequences for the hepatitis B virus surface antigen, the herpes simplex virus glycoprotein D, and the influenza virus hemagglutinin were inserted into a single vaccinia virus genome. Rabbits inoculated intravenously or intradermally with this polyvalent vaccinia virus recombinant produced antibodies reactive to all three authentic foreign antigens. In addition, the feasibility of multiple rounds of vaccination with recombinant vaccinia virus was demonstrated.

  2. Viruses, definitions and reality

    Directory of Open Access Journals (Sweden)

    Libia Herrero-Uribe

    2011-09-01

    Full Text Available Viruses are known to be abundant, ubiquitous, and to play a very important role in the health and evolution of life organisms. However, most biologists have considered them as entities separate from the realm of life and acting merely as mechanical artifacts that can exchange genes between different organisms. This article reviews some definitions of life organisms to determine if viruses adjust to them, and additionally, considers new discoveries to challenge the present definition of viruses. Definitions of life organisms have been revised in order to validate how viruses fit into them. Viral factories are discussed since these mini-organelles are a good example of the complexity of viral infection, not as a mechanical usurpation of cell structures, but as a driving force leading to the reorganization and modification of cell structures by viral and cell enzymes. New discoveries such as the Mimivirus, its virophage and viruses that produce filamentous tails when outside of their host cell, have stimulated the scientific community to analyze the current definition of viruses. One way to be free for innovation is to learn from life, without rigid mental structures or tied to the past, in order to understand in an integrated view the new discoveries that will be unfolded in future research. Life processes must be looked from the complexity and trans-disciplinarity perspective that includes and accepts the temporality of the active processes of life organisms, their interdependency and interrelation among them and their environment. New insights must be found to redefine life organisms, especially viruses, which still are defined using the same concepts and knowledge of the fifties. Rev. Biol. Trop. 59 (3: 993-998. Epub 2011 September 01.Los virus son abundantes, ubicuos, y juegan un papel muy importante en la salud y en la evolución de los organismos vivos. Sin embargo, la mayoría de los biólogos los siguen considerado como entidades separadas

  3. Ebola (Ebola Virus Disease): Transmission

    Science.gov (United States)

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  4. Ebola (Ebola Virus Disease): Prevention

    Science.gov (United States)

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  5. Ebola (Ebola Virus Disease): Treatment

    Science.gov (United States)

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  6. Ebola (Ebola Virus Disease): Diagnosis

    Science.gov (United States)

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  7. Special Issue: Honey Bee Viruses

    Directory of Open Access Journals (Sweden)

    Sebastian Gisder

    2015-10-01

    Full Text Available Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus, or a so far neglected virus species (Apis mellifera filamentous virus, and cutting edge technologies (mass spectrometry, RNAi approach applied in the field.

  8. Zika Virus Infection and Microcephaly

    OpenAIRE

    J Gordon Millichap

    2016-01-01

    A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy.

  9. Epstein-Barr virus test

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003513.htm Epstein-Barr virus antibody test To use the sharing features on this page, please enable JavaScript. Epstein-Barr virus antibody test is a blood test to detect ...

  10. Avian influenza viruses in humans.

    OpenAIRE

    Malik Peiris, J S

    2009-01-01

    Past pandemics arose from low pathogenic avian influenza (LPAI) viruses. In more recent times, highly pathogenic avian influenza (HPAI) H5N1, LPAI H9N2 and both HPAI and LPAI H7 viruses have repeatedly caused zoonotic disease in humans. Such infections did not lead to sustained human-to-human transmission. Experimental infection of human volunteers and seroepidemiological studies suggest that avian influenza viruses of other subtypes may also infect humans. Viruses of the H7 subtype appear to...

  11. Computer virus : design and detection

    OpenAIRE

    Arding, Petter; Hedelin, Hugo

    2014-01-01

    Computer viruses uses a few different techniques, with various intentions, toinfect files. However, what most of them have in common is that they wantto avoid detection by anti-malware software. To not get detected and stay unnoticed,virus creators have developed several methods for this. Anti-malwaresoftware is constantly trying to counter these methods of virus infections withtheir own detection-techniques. In this paper we have analyzed the differenttypes of viruses and their infection tec...

  12. Antigenic variants of rabies virus

    OpenAIRE

    Wiktor, TJ; Koprowski, H

    1980-01-01

    Antigenic variants of CVS-11 strain of rabies virus were selected after treatment of virus populations with monoclonal antibodies directed against the glycoprotein antigen of the virus. These variants resisted neutralization by the hybridoma antibody used for their selection. Two independently mutating antigenic sites could be distinguished when five variants were tested with nine hybridoma antibodies. The frequency of single epitope variants in a cloned rabies virus seed was approximately 1:...

  13. Rhabdomyolysis Associated with Parainfluenza Virus

    Directory of Open Access Journals (Sweden)

    Miltiadis Douvoyiannis

    2013-01-01

    Full Text Available Influenza virus is the most frequently reported viral cause of rhabdomyolysis. A 7-year-old child is presented with rhabdomyolysis associated with parainfluenza type 2 virus. Nine cases of rhabdomyolysis associated with parainfluenza virus have been reported. Complications may include electrolyte disturbances, acute renal failure, and compartment syndrome.

  14. Archaeal virus-host interactions

    NARCIS (Netherlands)

    Quax, T.E.F.

    2013-01-01

      The work presented in this thesis provides novel insights in several aspects of the molecular biology of archaea, bacteria and their viruses. Three fundamentally different groups of viruses are associated with the three domains of life. Archaeal viruses are characterized by a particularly

  15. Protecting Your Computer from Viruses

    Science.gov (United States)

    Descy, Don E.

    2006-01-01

    A computer virus is defined as a software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer. The existence of computer viruses--or the necessity of avoiding viruses--is part of using a computer. With the advent of the Internet, the door was opened wide for these…

  16. Ipomoviruses: Squash vein yellowing virus, Cucumber vein yellowing virus, Cassava brown streak virus, and Ugandan cassava brown streak virus

    Science.gov (United States)

    Ipomoviruses including Squash vein yellowing virus, Cucumber vein yellowing virus and Cassava brown streak virus are currently causing significant economic impact on crop production in several regions of the world. Only recently have results of detailed characterization of their whitefly transmissi...

  17. THE BIOLOGY OF INFLUENZA VIRUSES

    OpenAIRE

    Bouvier, Nicole M.; Palese, Peter

    2008-01-01

    The influenza viruses are characterized by segmented, negative-strand RNA genomes requiring an RNA-dependent RNA polymerase of viral origin for replication. The particular structure of the influenza virus genome and function of its viral proteins enable antigenic drift and antigenic shift. These processes result in viruses able to evade the long-term adaptive immune responses in many hosts.

  18. Avian influenza virus RNA extraction

    Science.gov (United States)

    The efficient extraction and purification of viral RNA is critical for down-stream molecular applications whether it is the sensitive and specific detection of virus in clinical samples, virus gene cloning and expression, or quantification of avian influenza (AI) virus by molecular methods from expe...

  19. Elucidating virus uptake and fusion by single virus tracing

    OpenAIRE

    Schupp, Dorothee Carolin

    2012-01-01

    Viruses are known to cause many diseases, from the common cold and cold sores to more serious diseases such as the Ebola virus disease and AIDS. Viruses have evolved different strategies to enter and infect cells. In order to infect a cell, viruses have to overcome the cell membrane barrier to deliver their genome to the site of replication. Enveloped viruses can either fuse directly at the plasma membrane or with an endosomal membrane after endocytic uptake. In this work, I studied the early...

  20. Relationship of lychnis ringspot virus to barley stripe mosaic virus and poa semilatent virus.

    Science.gov (United States)

    Hunter, B G; Smith, J; Fattouh, F; Jackson, A O

    1989-01-01

    Barley stripe mosaic virus (BSMV), poa semilatent virus (PSLV), and lychnis ringspot virus (LRSV) have previously been assigned to the hordeivirus group because of similarities in their particle morphology, physicochemical properties and serological analyses. However, the serological relationships of the three viruses have not been determined by direct comparison. The present study evaluated the relatedness of these viruses by Western and dot immunoblotting and by nucleic acid hybridizations. Serological analyses of the coat proteins separated by gel electrophoresis and of intact virus particles bound to nitrocellulose membranes revealed that BSMV and PSLV are distantly related, but that they are more closely related to each other than to LRSV. The genomic RNAs of the viruses failed to cross-hybridize in northern hybridization tests conducted at different temperatures. These comparisons showed that BSMV, PSLV and LRSV are distinct viruses with little nucleotide sequence relatedness. Thus our data provide additional support for their inclusion as separate members of the hordeivirus group. PMID:2722469

  1. Research on computer virus database management system

    Science.gov (United States)

    Qi, Guoquan

    2011-12-01

    The growing proliferation of computer viruses becomes the lethal threat and research focus of the security of network information. While new virus is emerging, the number of viruses is growing, virus classification increasing complex. Virus naming because of agencies' capture time differences can not be unified. Although each agency has its own virus database, the communication between each other lacks, or virus information is incomplete, or a small number of sample information. This paper introduces the current construction status of the virus database at home and abroad, analyzes how to standardize and complete description of virus characteristics, and then gives the information integrity, storage security and manageable computer virus database design scheme.

  2. Virus en Endodoncia

    OpenAIRE

    Hernández Vigueras, Scarlette; Salazar Navarrete, Luis; Pérez Tomás, Ricardo E.; Segura Egea, Juan José; Viñas, Miquel; López López, José

    2014-01-01

    La infección endodóntica es la infección que afecta al sistema de conductos radiculares y, sin duda, es el principal agente etiológico de las periodontitis apicales. Además, de las bacterias patógenas endodónticas, se ha buscado en los últimos años asociar la presencia de virus en distintos tipos de patología endodóntica. Los virus que más se han buscado y asociado son los pertenecientes a la familia herpesvirus, los cuales se han encontrado presentes en patologías periapicales principalmente...

  3. Zika virus: Indian perspectives

    Science.gov (United States)

    Mourya, Devendra T.; Shil, Pratip; Sapkal, Gajanan N.; Yadav, Pragya D.

    2016-01-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998

  4. [ZIKA--VIRUS INFECTION].

    Science.gov (United States)

    Velev, V

    2016-01-01

    This review summarizes the knowledge of the scientific community for Zika-virus infection. It became popular because of severe congenital damage causes of CNS in newborns whose mothers are infected during pregnancy, as well as the risk of pandemic distribution. Discusses the peculiarities of the biology and ecology of vectors--blood-sucking mosquitoes Aedes; stages in the spread of infection and practical problems which caused during pregnancy. Attention is paid to the recommendations that allow leading national and international medical organizations to deal with the threat Zika-virus infection. PMID:27509655

  5. Zika virus: Indian perspectives.

    Science.gov (United States)

    Mourya, Devendra T; Shil, Pratip; Sapkal, Gajanan N; Yadav, Pragya D

    2016-05-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998

  6. Sensing of RNA viruses

    DEFF Research Database (Denmark)

    Jensen, Søren; Thomsen, Allan Randrup

    2012-01-01

    Our knowledge regarding the contribution of the innate immune system in recognizing and subsequently initiating a host response to an invasion of RNA virus has been rapidly growing over the last decade. Descriptions of the receptors involved and the molecular mechanisms they employ to sense viral...... pathogen-associated molecular patterns have emerged in great detail. This review presents an overview of our current knowledge regarding the receptors used to detect RNA virus invasion, the molecular structures these receptors sense, and the involved downstream signaling pathways....

  7. Tenosinovitis por virus Chikungunya

    Directory of Open Access Journals (Sweden)

    Alfredo Seijo

    2014-12-01

    Full Text Available Se presenta a la consulta un hombre proveniente de la República Dominicana con una tenosinovitis del extensor del dedo medio derecho; en la convalecencia inmediata, segunda curva febril luego de 48 horas de permanecer asintomático de una enfermedad febril aguda, y marcada astenia, exantema pruriginoso, poliartralgias con impotencia funcional y rigidez articular generalizada. Los exámenes bioquímicos no aportaron datos de interés para el diagnóstico. La serología para virus dengue fue negativa. La detección de IgM y de anticuerpos neutralizantes para virus Chikungunya (CHIKV fueron positivos.

  8. Zika virus: Indian perspectives

    Directory of Open Access Journals (Sweden)

    Devendra T Mourya

    2016-01-01

    Full Text Available The emergence of Zika virus (ZiV, a mosquito borne Flavivirus like dengue (DEN and chikungunya (CHIK, in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective.

  9. Bovine Virus Diarrhea (BVD)

    OpenAIRE

    Hoar, Bruce R.

    2004-01-01

    Bovine virus diarrhea (BVD) is a complicated disease to discuss as it can result in a wide variety of disease problems from very mild to very severe. BVD can be one of the most devastating diseases cattle encounter and one of the hardest to get rid of when it attacks a herd. The viruses that cause BVD have been grouped into two genotypes, Type I and Type II. The disease syndrome caused by the two genotypes is basically the same, however disease caused by Type II infection is often more severe...

  10. 电喷雾串联质谱法定性分析新型毒品亚甲基双氧甲基卡西酮%Qualitative Analysis of New-type Drug bk-MDMA by ESI-MS/MS

    Institute of Scientific and Technical Information of China (English)

    周志刚; 严忠雍; 张小军; 杨宝峰

    2015-01-01

    建立一种准确定性奶茶等样品中亚甲基双氧甲基卡西酮(bk-MDMA)的电喷雾串联质谱检测方法.样品通过甲醇提取,提取液高速离心后用滤膜过滤,上机液用蠕动泵进样进行电喷雾串联质谱定性分析.通过母离子扫描和子离子扫描研究了bk-MDMA的质谱裂解途径,通过分析比较选择合适的定性离子.通过对锥孔电压、碰撞电压等质谱条件的优化和基质干扰分析,建立了合适的串联质谱检测条件.电喷雾串联质谱方法与GC-MS方法相比更加快速简便,通过串联质谱的二级质谱定性准确度更高.利用本方法对5个物证实际样品进行了分析,结果显示均含有bk-MDMA.本方法快速、准确、灵敏度高,可广泛用于司法物证鉴定等领域bk-MDMA的定性分析.

  11. Parainfluenza Virus 5 Expressing the G Protein of Rabies Virus Protects Mice after Rabies Virus Infection

    OpenAIRE

    Huang, Ying; Chen, Zhenhai; Huang, Junhua; Fu, Zhenfang; He, Biao

    2014-01-01

    Rabies remains a major public health threat around the world. Once symptoms appear, there is no effective treatment to prevent death. In this work, we tested a recombinant parainfluenza virus 5 (PIV5) strain expressing the glycoprotein (G) of rabies (PIV5-G) as a therapy for rabies virus infection: we have found that PIV5-G protected mice as late as 6 days after rabies virus infection. PIV5-G is a promising vaccine for prevention and treatment of rabies virus infection.

  12. Characterization of highly frequent epitope-specific CD45RA+/CCR7+/- T lymphocyte responses against p53-binding domains of the human polyomavirus BK large tumor antigen in HLA-A*0201+ BKV-seropositive donors

    Directory of Open Access Journals (Sweden)

    Zajac Paul

    2006-11-01

    Full Text Available Abstract Human polyomavirus BK (BKV has been implicated in oncogenic transformation. Its ability to replicate is determined by the binding of its large tumor antigen (LTag to products of tumor-suppressor genes regulating cell cycle, as specifically p53. We investigated CD8+ T immune responses to BKV LTag portions involved in p53 binding in HLA-A*0201+ BKV LTag experienced individuals. Peptides selected from either p53-binding region (LTag351–450 and LTag533–626 by current algorithms and capacity to bind HLA-A*0201 molecule were used to stimulate CD8+ T responses, as assessed by IFN-γ gene expression ex vivo and detected by cytotoxicity assays following in vitro culture. We observed epitope-specific immune responses in all HLA-A*0201+ BKV LTag experienced individuals tested. At least one epitope, LTag579–587; LLLIWFRPV, was naturally processed in non professional antigen presenting cells and induced cytotoxic responses with CTL precursor frequencies in the order of 1/20'000. Antigen specific CD8+ T cells were only detectable in the CD45RA+ subset, in both CCR7+ and CCR7- subpopulations. These data indicate that widespread cellular immune responses against epitopes within BKV LTag-p53 binding regions exist and question their roles in immunosurveillance against tumors possibly associated with BKV infection.

  13. Single Assay Detection of Acute Bee Paralysis Virus, Kashmir Bee Virus and Israeli Acute Paralysis Virus

    DEFF Research Database (Denmark)

    Francis, Roy Mathew; Kryger, Per

    2012-01-01

    A new RT-PCR primer pair designed to identify Acute Bee Paralysis Virus (ABPV), Kashmir Bee Virus (KBV) or Israeli Acute Bee Paralysis Virus (IAPV) of honey bees (Apis mellifera L.) in a single assay is described. These primers are used to screen samples for ABPV, KBV, or IAPV in a single RT...

  14. Viruses, Artificial Viruses and Virus-Based Structures for Biomedical Applications

    NARCIS (Netherlands)

    van Rijn, Patrick; Schirhagl, Romana

    2016-01-01

    Nanobiomaterials such as virus particles and artificial virus particles offer tremendous opportunities to develop new biomedical applications such as drug- or gene-delivery, imaging and sensing but also improve understanding of biological mechanisms. Recent advances within the field of virus-based s

  15. Bat flight and zoonotic viruses

    Science.gov (United States)

    O'Shea, Thomas; Cryan, Paul M.; Cunningham, Andrew A.; Fooks, Anthony R.; Hayman, David T.S.; Luis, Angela D.; Peel, Alison J.; Plowright, Raina K.; Wood, James L.N.

    2014-01-01

    Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host–virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts.

  16. The FEFM Virus.

    Science.gov (United States)

    Cjelli, Dirk

    1994-01-01

    Discussion of human performance technology (HPT) interventions focuses on requests for solutions to problems that involve conflict between the FEFM ("Fix 'em for me") Virus and the WIIFM ("What's in it for me?") Requirement. Building a relationship of mutual trust and confidence with the client and demonstrating responsiveness are advocated. (LRW)

  17. The Virus Business

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Panda, a computer infection that wreaked havoc on computers across China, brought attention to the country’s underground computer virus business, but it was just the tip of a growing iceberg The cute and cuddly panda, a nation- al treasure of China

  18. Viruses of Haloarchaea

    Directory of Open Access Journals (Sweden)

    Alison W. S. Luk

    2014-11-01

    Full Text Available In hypersaline environments, haloarchaea (halophilic members of the Archaea are the dominant organisms, and the viruses that infect them, haloarchaeoviruses are at least ten times more abundant. Since their discovery in 1974, described haloarchaeoviruses include head-tailed, pleomorphic, spherical and spindle-shaped morphologies, representing Myoviridae, Siphoviridae, Podoviridae, Pleolipoviridae, Sphaerolipoviridae and Fuselloviridae families. This review overviews current knowledge of haloarchaeoviruses, providing information about classification, morphotypes, macromolecules, life cycles, genetic manipulation and gene regulation, and host-virus responses. In so doing, the review incorporates knowledge from laboratory studies of isolated viruses, field-based studies of environmental samples, and both genomic and metagenomic analyses of haloarchaeoviruses. What emerges is that some haloarchaeoviruses possess unique morphological and life cycle properties, while others share features with other viruses (e.g., bacteriophages. Their interactions with hosts influence community structure and evolution of populations that exist in hypersaline environments as diverse as seawater evaporation ponds, to hot desert or Antarctic lakes. The discoveries of their wide-ranging and important roles in the ecology and evolution of hypersaline communities serves as a strong motivator for future investigations of both laboratory-model and environmental systems.

  19. Viruses of haloarchaea.

    Science.gov (United States)

    Luk, Alison W S; Williams, Timothy J; Erdmann, Susanne; Papke, R Thane; Cavicchioli, Ricardo

    2014-01-01

    In hypersaline environments, haloarchaea (halophilic members of the Archaea) are the dominant organisms, and the viruses that infect them, haloarchaeoviruses are at least ten times more abundant. Since their discovery in 1974, described haloarchaeoviruses include head-tailed, pleomorphic, spherical and spindle-shaped morphologies, representing Myoviridae, Siphoviridae, Podoviridae, Pleolipoviridae, Sphaerolipoviridae and Fuselloviridae families. This review overviews current knowledge of haloarchaeoviruses, providing information about classification, morphotypes, macromolecules, life cycles, genetic manipulation and gene regulation, and host-virus responses. In so doing, the review incorporates knowledge from laboratory studies of isolated viruses, field-based studies of environmental samples, and both genomic and metagenomic analyses of haloarchaeoviruses. What emerges is that some haloarchaeoviruses possess unique morphological and life cycle properties, while others share features with other viruses (e.g., bacteriophages). Their interactions with hosts influence community structure and evolution of populations that exist in hypersaline environments as diverse as seawater evaporation ponds, to hot desert or Antarctic lakes. The discoveries of their wide-ranging and important roles in the ecology and evolution of hypersaline communities serves as a strong motivator for future investigations of both laboratory-model and environmental systems. PMID:25402735

  20. Viruses of the Archaea

    DEFF Research Database (Denmark)

    Basta, T.; Garrett, Roger Antony; Prangishvili,, David

    Double-stranded deoxyribonucleic acid (DNA) viruses that infect members of the third domain of life, the Archaea, are diverse and exceptional in both their morphotypes and their genomic properties. The majority of characterized species infect hyperthermophilic hosts and carry morphological features...

  1. The virus of management

    DEFF Research Database (Denmark)

    Kjær, Peter; Frankel, Christian

    2003-01-01

    concrete management knowledge and practice. The article isstructured as follows. After the introduction, we first develop the notion of organizational virus asinto an analytical approach. Second, we discern in the work of Frederick Taylor on scientificmanagement and Max Weber on bureaucracy, two quite...

  2. Viruses and febrile seizures

    NARCIS (Netherlands)

    Zeijl, J.H. van

    2004-01-01

    We conclude that viral infections are the main cause of febrile seizures, with an important role for influenza A, HHV-6 and HHV-7. We showed that several viral infections not only contribute to initial febrile seizures, but also to recurrences. Viruses could not be detected in the CSF of children wi

  3. Evolutionary relationship of alfalfa mosaic virus with cucumber mosaic virus and brome mosaic virus

    OpenAIRE

    Savithri, HS; Murthy, MRN

    1983-01-01

    The amino acid sequences of the non-structural protein (molecular weight 35,000; 3a protein) from three plant viruses - cucumber mosaic, brome mosaic and alfalfa mosaic have been systematically compared using the partial genomic sequences for these three viruses already available. The 3a protein of cucumber mosaic virus has an amino acid sequence homology of 33.7% with the corresponding protein of brome mosaic virus. A similar protein from alfalfa mosaic virus has a homology of 18.2% and 14.2...

  4. Molecular epidemiology of respiratory viruses in virus-induced asthma

    Directory of Open Access Journals (Sweden)

    Hiroyuki eTsukagoshi

    2013-09-01

    Full Text Available Acute respiratory illness (ARI due to various viruses is not only the most common cause of upper respiratory infection in humans but is also a major cause of morbidity and mortality, leading to diseases such as bronchiolitis and pneumonia. Previous studies have shown that respiratory syncytial virus (RSV, human rhinovirus (HRV, human metapneumovirus (HMPV, human parainfluenza virus (HPIV, and human enterovirus (HEV infections may be associated with virus-induced asthma. For example, it has been suggested that HRV infection is detected in the acute exacerbation of asthma and infection is prolonged. Thus it is believed that the main etiological cause of asthma is ARI viruses. Furthermore, the number of asthma patients in most industrial countries has greatly increased, resulting in a morbidity rate of around 10-15% of the population. However, the relationships between viral infections, host immune response, and host factors in the pathophysiology of asthma remain unclear. To gain a better understanding of the epidemiology of virus-induced asthma, it is important to assess both the characteristics of the viruses and the host defense mechanisms. Molecular epidemiology enables us to understand the pathogenesis of microorganisms by identifying specific pathways, molecules, and genes that influence the risk of developing a disease. However, the epidemiology of various respiratory viruses associated with virus-induced asthma is not fully understood. Therefore, in this article, we review molecular epidemiological studies of RSV, HRV, HPIV, and HMPV infection associated with virus-induced asthma.

  5. Presence and Distribution of Tobacco Viruses in Serbia

    OpenAIRE

    Nataša Duduk; Aleksandra Bulajić; Janoš Berenji; Ivana Đekić; Bojan Duduk; Branka Krstić

    2006-01-01

    Infection with a large number of plant viruses could imperil tobacco yield and quality. Tobacco is a natural host for more than 20 viruses, among which the most important and economically harmful are tobacco mosaic virus (TMV), tomato spotted wilt virus (TSWV), cucumber mosaic virus (CMV), potato virus Y (PVY), alfalfa mosaic virus (AMV), tobacco ringspot virus (TRSV), tobacco each virus (TEV) and tobacco vein mottling virus (TVMV).The occurence and distribution of tobacco viruses were invest...

  6. Single virus genomics: a new tool for virus discovery.

    Directory of Open Access Journals (Sweden)

    Lisa Zeigler Allen

    Full Text Available Whole genome amplification and sequencing of single microbial cells has significantly influenced genomics and microbial ecology by facilitating direct recovery of reference genome data. However, viral genomics continues to suffer due to difficulties related to the isolation and characterization of uncultivated viruses. We report here on a new approach called 'Single Virus Genomics', which enabled the isolation and complete genome sequencing of the first single virus particle. A mixed assemblage comprised of two known viruses; E. coli bacteriophages lambda and T4, were sorted using flow cytometric methods and subsequently immobilized in an agarose matrix. Genome amplification was then achieved in situ via multiple displacement amplification (MDA. The complete lambda phage genome was recovered with an average depth of coverage of approximately 437X. The isolation and genome sequencing of uncultivated viruses using Single Virus Genomics approaches will enable researchers to address questions about viral diversity, evolution, adaptation and ecology that were previously unattainable.

  7. Neuroteratogenic Viruses and Lessons for Zika Virus Models.

    Science.gov (United States)

    Kim, Kenneth; Shresta, Sujan

    2016-08-01

    The Centers for Disease Control and Prevention has confirmed that Zika virus (ZIKV) causes congenital microcephaly. ZIKV now joins five other neuroteratogenic (NT) viruses in humans and ZIKV research is in its infancy. In addition, there is only one other NT human arbovirus (Venezuelan equine encephalitis virus), which is also poorly understood. But further insight into ZIKV can be found by evaluating arboviruses in domestic animals, of which there are at least seven NT viruses, three of which have been well studied. Here we review two key anatomical structures involved in modeling transplacental NT virus transmission: the placenta and the fetal blood-brain barrier. We then survey major research findings regarding transmission of NT viruses for guidance in establishing a mouse model of Zika disease that is crucial for a better understanding of ZIKV transmission and pathogenesis. PMID:27387029

  8. 9 CFR 113.215 - Bovine Virus Diarrhea Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Bovine Virus Diarrhea Vaccine, Killed... REQUIREMENTS Killed Virus Vaccines § 113.215 Bovine Virus Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea... paragraph. (i) Eight bovine virus diarrhea susceptible calves (five vaccinates and three controls) shall...

  9. Rapid Detection and Quantification of RNA of Ebola and Marburg Viruses, Lassa Virus, Crimean-Congo Hemorrhagic Fever Virus, Rift Valley Fever Virus, Dengue Virus, and Yellow Fever Virus by Real-Time Reverse Transcription-PCR

    OpenAIRE

    Drosten, Christian; Göttig, Stephan; Schilling, Stefan; Asper, Marcel; Panning, Marcus; Schmitz, Herbert; Günther, Stephan

    2002-01-01

    Viral hemorrhagic fevers (VHFs) are acute infections with high case fatality rates. Important VHF agents are Ebola and Marburg viruses (MBGV/EBOV), Lassa virus (LASV), Crimean-Congo hemorrhagic fever virus (CCHFV), Rift Valley fever virus (RVFV), dengue virus (DENV), and yellow fever virus (YFV). VHFs are clinically difficult to diagnose and to distinguish; a rapid and reliable laboratory diagnosis is required in suspected cases. We have established six one-step, real-time reverse transcripti...

  10. Resveratrol, sirtuins, and viruses.

    Science.gov (United States)

    Yang, Tao; Li, Shugang; Zhang, Xuming; Pang, Xiaowu; Lin, Qinlu; Cao, Jianzhong

    2015-11-01

    Resveratrol is a natural phenolic product found in some plants in response to stress and has been linked to the many health benefits of red wine. Over the past several decades, a great deal of research has identified diverse biological roles associated with resveratrol, including anti-oxidant, anti-proliferation, anti-inflammation, anti-cancer, anti-fungal, and antiviral activities. Such biological activities of resveratrol are likely mediated through multiple cellular targets or pathways, such as sirtuins, a family of NAD(+)-dependent deacetylases. In this treatise, the literatures focusing on the roles of resveratrol and sirtuins in modulating infections by a broad-spectrum of viruses are reviewed, with an emphasis on its potential antiviral mechanisms. A working model about the effects of resveratrol on virus infection is proposed to stimulate further researches on this exciting topic. PMID:26479742

  11. Vade retro virus

    OpenAIRE

    Bardini, Thierry

    2015-01-01

    Avec l’aide de récents résultats de la virologie, le présent article se concentre sur les virus en tant que participants d’une possible redéfinition de la frontière inférieure de la vie, en tant que vie minimale. À l’heure du triomphe de la viralité dans la cyberculture contemporaine, l’auteur avance que l’on devrait considérer les virus comme les premières formes d’entités convergentes, c’est-à-dire existant par-delà la division du monde en deux phases distinctes et incompatibles, numérique ...

  12. [Ebola virus disease: Update].

    Science.gov (United States)

    de la Calle-Prieto, Fernando; Arsuaga-Vicente, Marta; Mora-Rillo, Marta; Arnalich-Fernandez, Francisco; Arribas, Jose Ramon

    2016-01-01

    The first known Ebola outbreak occurred in 1976. Since then, 24 limited outbreaks had been reported in Central Africa, but never affecting more than 425 persons. The current outbreak in Western Africa is the largest in history with 28,220 reported cases and 11,291 deaths. The magnitude of the epidemic has caused worldwide alarm. For the first time, evacuated patients were treated outside Africa, and secondary cases have occurred in Spain and the United States. Since the start of the current epidemic, our knowledge about the epidemiology, clinical picture, laboratory findings, and virology of Ebola virus disease has considerably expanded. For the first time, experimental treatment has been tried, and there have been spectacular advances in vaccine development. A review is presented of these advances in the knowledge of Ebola virus disease. PMID:26774254

  13. Proteorhodopsin genes in giant viruses

    Directory of Open Access Journals (Sweden)

    Yutin Natalya

    2012-10-01

    Full Text Available Abstract Viruses with large genomes encode numerous proteins that do not directly participate in virus biogenesis but rather modify key functional systems of infected cells. We report that a distinct group of giant viruses infecting unicellular eukaryotes that includes Organic Lake Phycodnaviruses and Phaeocystis globosa virus encode predicted proteorhodopsins that have not been previously detected in viruses. Search of metagenomic sequence data shows that putative viral proteorhodopsins are extremely abundant in marine environments. Phylogenetic analysis suggests that giant viruses acquired proteorhodopsins via horizontal gene transfer from proteorhodopsin-encoding protists although the actual donor(s could not be presently identified. The pattern of conservation of the predicted functionally important amino acid residues suggests that viral proteorhodopsin homologs function as sensory rhodopsins. We hypothesize that viral rhodopsins modulate light-dependent signaling, in particular phototaxis, in infected protists. This article was reviewed by Igor B. Zhulin and Laksminarayan M. Iyer. For the full reviews, see the Reviewers’ reports section.

  14. Geographic distribution of Bhanja virus.

    Science.gov (United States)

    Hubálek, Z

    1987-01-01

    A review on the geographic distribution, vectors and hosts of Bhanja virus (Bunyaviridae) is based on reports about: isolations of the virus; antibody surveys. Bhanja virus has been isolated in 15 countries of Asia, Africa and Europe, and antibodies against it have been detected in 15 additional countries. Vector range includes ticks of the family Ixodidae (subfam. Amblyomminae; not subfam. Ixodinae): 13 species of 6 genera (Haemaphysalis, Dermacentor, Hyalomma, Amblyomma, Rhipicephalus and Boophilus) yielded the virus. Bhanja virus has only rarely been isolated from vertebrates (Atelerix, Xerus, Ovis, Bos; possibly bats), though antibodies have been detected frequently in a wide range of mammals (Ruminantia being the major hosts), in several species of birds (Passeriformes, Galliformes) and even reptiles (Ophisaurus apodus). Natural foci of the Bhanja virus infections are of the boskematic type (sensu Rosický), associated closely with pastures of domestic ruminants infested by ticks in the regions of tropical, subtropical and partly temperate climatic zones. PMID:3108117

  15. Ebola Virus Disease

    Centers for Disease Control (CDC) Podcasts

    2014-08-08

    This podcast provides general information about Ebola virus disease and the outbreak in West Africa. The program contains remarks from CDC Director Dr. Tom Frieden, as well as a brief description of CDC’s response efforts.  Created: 8/8/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 8/8/2014.

  16. Framework Ebola Virus Disease

    OpenAIRE

    2014-01-01

    The current outbreak of Ebola virus disease (EVD) in West Africa is the largest recognized outbreak of this disease to date. It is also the first such outbreak including cases infected outside of Africa. The risk of an introduction of EVD to Germany (defined as an infected person entering Germany and passing the infection to others) is very low. But it cannot be totally excluded that in isolated instances infected persons could enter unrecognizably during the incubation period, potentiall...

  17. Viruses and drinking water

    OpenAIRE

    Cartwright, R Y

    1997-01-01

    There is no evidence to indicate that there is a risk of acquiring a virus infection through the consumption of properly treated drinking water, provided the integrity of the distribution system is maintained and there is no post-treatment contamination. The consumption of inadequately treated, untreated or post-treatment contaminated water is, however, associated with a risk of hepatitis A, hepatitis E and viral gastroenteritis. The use of the standard bacterial indicators for water monitori...

  18. Parainfluenza Virus Infection.

    Science.gov (United States)

    Branche, Angela R; Falsey, Ann R

    2016-08-01

    Human parainfluenza viruses (HPIVs) are single-stranded, enveloped RNA viruses of the Paramyoviridaie family. There are four serotypes which cause respiratory illnesses in children and adults. HPIVs bind and replicate in the ciliated epithelial cells of the upper and lower respiratory tract and the extent of the infection correlates with the location involved. Seasonal HPIV epidemics result in a significant burden of disease in children and account for 40% of pediatric hospitalizations for lower respiratory tract illnesses (LRTIs) and 75% of croup cases. Parainfluenza viruses are associated with a wide spectrum of illnesses which include otitis media, pharyngitis, conjunctivitis, croup, tracheobronchitis, and pneumonia. Uncommon respiratory manifestations include apnea, bradycardia, parotitis, and respiratory distress syndrome and rarely disseminated infection. Immunity resulting from disease in childhood is incomplete and reinfection with HPIV accounts for 15% of respiratory illnesses in adults. Severe disease and fatal pneumonia may occur in elderly and immunocompromised adults. HPIV pneumonia in recipients of hematopoietic stem cell transplant (HSCT) is associated with 50% acute mortality and 75% mortality at 6 months. Though sensitive molecular diagnostics are available to rapidly diagnose HPIV infection, effective antiviral therapies are not available. Currently, treatment for HPIV infection is supportive with the exception of croup where the use of corticosteroids has been found to be beneficial. Several novel drugs including DAS181 appear promising in efforts to treat severe disease in immunocompromised patients, and vaccines to decrease the burden of disease in young children are in development. PMID:27486735

  19. Computer viruses and electronic mail

    OpenAIRE

    Buzzi, Marina

    2002-01-01

    Today the Internet is a valuable source of information as well as a powerful communication medium, with undoubted social and economic benefits, however it also poses some security risks. Virsuses may hide in email attachments or in appartently innocent applications directly downloadable from the Internet. In this work we give a brief overview of virus types and main defense techniques. Then we present statistical data of virus attacks revealed by an anti-virus SW activated on our e-mail serve...

  20. Lagos Bat Virus in Kenya▿

    OpenAIRE

    Kuzmin, Ivan V.; Niezgoda, Michael; Franka, Richard; Agwanda, Bernard; Markotter, Wanda; Beagley, Janet C.; Urazova, Olga Y.; Breiman, Robert F.; Rupprecht, Charles E.

    2008-01-01

    During lyssavirus surveillance, 1,221 bats of at least 30 species were collected from 25 locations in Kenya. One isolate of Lagos bat virus (LBV) was obtained from a dead Eidolon helvum fruit bat. The virus was most similar phylogenetically to LBV isolates from Senegal (1985) and from France (imported from Togo or Egypt; 1999), sharing with these viruses 100% nucleoprotein identity and 99.8 to 100% glycoprotein identity. This genome conservancy across space and time suggests that LBV is well ...

  1. Variant (Swine Origin) Influenza Viruses in Humans

    Science.gov (United States)

    ... Past Newsletters Variant (Swine Origin) Influenza Viruses in Humans Language: English Español Recommend on Facebook Tweet ... Page Background Reporting Additional Information Key Facts about Human Infections with Variant Viruses (Swine Origin Influenza Viruses ...

  2. Dengue virus growth, purification, and fluorescent labeling.

    Science.gov (United States)

    Zhang, Summer; Chan, Kuan Rong; Tan, Hwee Cheng; Ooi, Eng Eong

    2014-01-01

    The early events of the dengue virus life cycle involve virus binding, internalization, trafficking, and fusion. Fluorescently labeled viruses can be used to visualize these early processes. As dengue virus has 180 identical copies of the envelope protein attached to the membrane surface and is surrounded by a lipid membrane, amine-reactive (Alexa Fluor) or lipophilic (DiD) dyes can be used for virus labeling. These dyes are highly photostable and are ideal for studies involving cellular uptake and endosomal transport. To improve virus labeling efficiency and minimize the nonspecific labeling of nonviral proteins, virus concentration and purification precede fluorescent labeling of dengue viruses. Besides using these viruses for single-particle tracking, DiD-labeled viruses can also be used to distinguish serotype-specific from cross-neutralizing antibodies. Here the details of virus concentration, purification, virus labeling, applications, and hints of troubleshooting are described. PMID:24696327

  3. Zika Virus and Complications: Questions and Answers

    Science.gov (United States)

    ... Feed Youtube Twitter Facebook Google + iTunes Play Store Zika virus and complications: Questions and answers Online Q& ... a cause of microcephaly and Guillain-Barré syndrome. Zika virus Updated! How do people catch Zika virus? ...

  4. Chikungunya Virus: What You Need to Know

    Science.gov (United States)

    Chikungunya Virus: What you need to know Chikungunya (pronunciation: \\chik-en-gun-ye) is: A virus spread through Aedes species mosquito bites. Aedes mosquitoes also spread dengue and Zika viruses. A risk to anyone traveling to a region ...

  5. Genome of crocodilepox virus.

    Science.gov (United States)

    Afonso, C L; Tulman, E R; Delhon, G; Lu, Z; Viljoen, G J; Wallace, D B; Kutish, G F; Rock, D L

    2006-05-01

    Here, we present the genome sequence, with analysis, of a poxvirus infecting Nile crocodiles (Crocodylus niloticus) (crocodilepox virus; CRV). The genome is 190,054 bp (62% G+C) and predicted to contain 173 genes encoding proteins of 53 to 1,941 amino acids. The central genomic region contains genes conserved and generally colinear with those of other chordopoxviruses (ChPVs). CRV is distinct, as the terminal 33-kbp (left) and 13-kbp (right) genomic regions are largely CRV specific, containing 48 unique genes which lack similarity to other poxvirus genes. Notably, CRV also contains 14 unique genes which disrupt ChPV gene colinearity within the central genomic region, including 7 genes encoding GyrB-like ATPase domains similar to those in cellular type IIA DNA topoisomerases, suggestive of novel ATP-dependent functions. The presence of 10 CRV proteins with similarity to components of cellular multisubunit E3 ubiquitin-protein ligase complexes, including 9 proteins containing F-box motifs and F-box-associated regions and a homologue of cellular anaphase-promoting complex subunit 11 (Apc11), suggests that modification of host ubiquitination pathways may be significant for CRV-host cell interaction. CRV encodes a novel complement of proteins potentially involved in DNA replication, including a NAD(+)-dependent DNA ligase and a protein with similarity to both vaccinia virus F16L and prokaryotic serine site-specific resolvase-invertases. CRV lacks genes encoding proteins for nucleotide metabolism. CRV shares notable genomic similarities with molluscum contagiosum virus, including genes found only in these two viruses. Phylogenetic analysis indicates that CRV is quite distinct from other ChPVs, representing a new genus within the subfamily Chordopoxvirinae, and it lacks recognizable homologues of most ChPV genes involved in virulence and host range, including those involving interferon response, intracellular signaling, and host immune response modulation. These data

  6. Towards Metamorphic Virus Recognition Using Eigenviruses

    OpenAIRE

    Saleh, Moustafa

    2012-01-01

    Metamorphic viruses are considered the most dangerous of all computer viruses. Unlike other computer viruses that can be detected statically using static signature technique or dynamically using emulators, metamorphic viruses change their code to avoid such detection techniques. This makes metamorphic viruses a real challenge for computer security researchers. In this thesis, we investigate the techniques used by metamorphic viruses to alter their code, such as trivial code insertion, instruc...

  7. Epigenetic mechanisms in virus-induced tumorigenesis

    OpenAIRE

    Poreba, Elzbieta; Broniarczyk, Justyna Karolina; Gozdzicka-Jozefiak, Anna

    2011-01-01

    About 15–20% of human cancers worldwide have viral etiology. Emerging data clearly indicate that several human DNA and RNA viruses, such as human papillomavirus, Epstein–Barr virus, Kaposi’s sarcoma-associated herpesvirus, hepatitis B virus, hepatitis C virus, and human T-cell lymphotropic virus, contribute to cancer development. Human tumor-associated viruses have evolved multiple molecular mechanisms to disrupt specific cellular pathways to facilitate aberrant replication. Although oncogeni...

  8. Computer virus information update CIAC-2301

    Energy Technology Data Exchange (ETDEWEB)

    Orvis, W.J.

    1994-01-15

    While CIAC periodically issues bulletins about specific computer viruses, these bulletins do not cover all the computer viruses that affect desktop computers. The purpose of this document is to identify most of the known viruses for the MS-DOS and Macintosh platforms and give an overview of the effects of each virus. The authors also include information on some windows, Atari, and Amiga viruses. This document is revised periodically as new virus information becomes available. This document replaces all earlier versions of the CIAC Computer virus Information Update. The date on the front cover indicates date on which the information in this document was extracted from CIAC`s Virus database.

  9. Evolution of Computer Virus Concealment and Anti-Virus Techniques: A Short Survey

    OpenAIRE

    Rad, Babak Bashari; Masrom, Maslin; Ibrahim, Suhaimi

    2011-01-01

    This paper presents a general overview on evolution of concealment methods in computer viruses and defensive techniques employed by anti-virus products. In order to stay far from the anti-virus scanners, computer viruses gradually improve their codes to make them invisible. On the other hand, anti-virus technologies continually follow the virus tricks and methodologies to overcome their threats. In this process, anti-virus experts design and develop new methodologies to make them stronger, mo...

  10. Reverse genetics with animal viruses

    International Nuclear Information System (INIS)

    Full text: Reverse genetics of negative-strand RNA viruses (NSV), which allows generation of recombinant viruses entirely from cloned cDNA, has progressed rapidly in the past decade. NSV are a large and diverse group of enveloped viruses of both medical and veterinary importance. They differ widely in morphology, genome structure and host interactions. The first NSV that was completely amenable to genetic manipulation is the neurotropathogenic rabies virus of the rhabdovirus family. In subsequent years, vesicular stomatitis virus and a number of viruses belonging to the family Paramyxoviridae, including viruses causing important animal diseases such as rinderpest virus, canine distemper virus, bovine respiratory syncytial virus, bovine parainfluenza virus and Newcastle disease virus (NDV), succumbed to genetic engineering. The ability to genetically manipulate NSV opens a wide range of possibilities to study the virus biology and develop improved vaccines. Identification and analysis of attenuating mutations using the recombinant system could lead to generation of safe vaccine strains. Introduction of one of the previously studied mutation into an infectious rabies virus (RV) clone by replacing the arginine at position 333 of RV glycoprotein (G-protein) by an aspartic acid resulted in a dramatic attenuation. Combination of this mutation with a deletion that eliminates the interaction between RV P-protein and the cytoplasmic dynein light chain (LC8), which is presumably involved in retrograde transport of RV, further attenuates the rabies virus by 30-fold after intramuscular inoculation. Since extreme attenuation may adversely affect immunogenicity, reverse genetics was used to introduce an additional Gprotein to the step-wise attenuated RV to increase its effectiveness. The resultant recombinant virus may be helpful in developing a highly safe and effective live RV vaccine for oral immunizations of animals. Reverse genetics of NSV has also helped in providing

  11. Zika Virus Infection and Microcephaly

    Directory of Open Access Journals (Sweden)

    J. Gordon Millichap

    2016-03-01

    Full Text Available A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy.

  12. Are viruses our oldest ancestors?

    OpenAIRE

    Moelling, Karin

    2012-01-01

    We tend to regard viruses only as pathogens and thereby dismiss their crucial importance for the evolution of life. Viruses were not only the probable precursors of the first cells, but they have helped to shape and build the genomes of all species, including humans.

  13. Zika Virus Infection and Microcephaly.

    Science.gov (United States)

    Millichap, J Gordon

    2016-01-01

    A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy. PMID:27004142

  14. El virus del zika

    OpenAIRE

    Sáez García, Cristina

    2016-01-01

    El propósito de este trabajo es hacer una revisión sobre los datos conocidos actualmente relacionados con la infección por el virus Zika y sus consecuencias a nivel neurológico en el desarrollo fetal. La prevención se vuelve esencial contra esta enfermedad: Al no existir vacuna disponible, la actuación debe centrarse en evitar la picadura del mosquito, especialmente aquellas mujeres embarazadas. Las cifras actuales de infectados, y las de bebés nacidos con microcefalia resultan...

  15. Genome of Crocodilepox Virus

    OpenAIRE

    Afonso, C. L.; Tulman, E. R.; Delhon, G.; Lu, Z.; Viljoen, G. J.; Wallace, D. B.; Kutish, G. F.; Rock, D. L.

    2006-01-01

    Here, we present the genome sequence, with analysis, of a poxvirus infecting Nile crocodiles (Crocodylus niloticus) (crocodilepox virus; CRV). The genome is 190,054 bp (62% G+C) and predicted to contain 173 genes encoding proteins of 53 to 1,941 amino acids. The central genomic region contains genes conserved and generally colinear with those of other chordopoxviruses (ChPVs). CRV is distinct, as the terminal 33-kbp (left) and 13-kbp (right) genomic regions are largely CRV specific, containin...

  16. Tenosinovitis por virus Chikungunya

    OpenAIRE

    Alfredo Seijo; Victoria Luppo; Alejandra Morales; Elisa Gancedo; Yamila Romer; Jorge Correa; Gladys Poustis; Sergio Giamperetti; Cintia Fabbri; Delia Enría

    2014-01-01

    Se presenta a la consulta un hombre proveniente de la República Dominicana con una tenosinovitis del extensor del dedo medio derecho; en la convalecencia inmediata, segunda curva febril luego de 48 horas de permanecer asintomático de una enfermedad febril aguda, y marcada astenia, exantema pruriginoso, poliartralgias con impotencia funcional y rigidez articular generalizada. Los exámenes bioquímicos no aportaron datos de interés para el diagnóstico. La serología para virus dengue fue negativa...

  17. Feline immunodeficiency virus infection.

    Science.gov (United States)

    Pedersen, N C; Yamamoto, J K; Ishida, T; Hansen, H

    1989-05-01

    Feline immunodeficiency virus (FIV) (formerly feline T-lymphotropic lentivirus or FTLV) was first isolated from a group of cats in Petaluma, California in 1986. The virus is a typical lentivirus in gross and structural morphology. It replicates preferentially but not exclusively in feline T-lymphoblastoid cells, where it causes a characteristic cytopathic effect. The major structural proteins are 10, 17 (small gag), 28 (major core), 31 (endonuclease?), 41 (transmembrane?), 52 (core precursor polyprotein), 54/62 (reverse transcriptase?), and 110/130 (major envelope) kilodaltons in size. The various proteins are antigenically distinguishable from those of other lentiviruses, although serum from EIAV-infected horses will cross-react with some FIV antigens. Kittens experimentally infected with FIV manifest a transient (several days to 2 weeks) fever and neutropenia beginning 4 to 8 weeks after inoculation. This is associated with a generalized lymphadenopathy that persists for up to 9 months. Most cats recover from this initial phase of the disease and become lifelong carriers of the virus. Complete recovery does not occur to any extent in nature or in the laboratory setting. One experimentally infected cat died from a myeloproliferative disorder several months after infection. The terminal AIDS-like phase of the illness has been seen mainly in naturally infected cats. It appears a year or more following the initial infection in an unknown proportion of infected animals. FIV has been identified in cats from all parts of the world. It is most prevalent in high density populations of free roaming cats (feral and pet), and is very uncommon in closed purebred catteries. Male cats are twice as likely to become infected as females. Older male cats adopted as feral or stray animals are at the highest risk of infection, therefore. The infection rate among freely roaming cats rises throughout life, and reaches levels ranging from less than 1% to 12% or more depending on the

  18. Sunshine virus in Australian pythons.

    Science.gov (United States)

    Hyndman, Timothy H; Shilton, Cathy M; Doneley, Robert J T; Nicholls, Philip K

    2012-12-28

    Sunshine virus is a recently discovered novel paramyxovirus that is associated with illness in snakes. It does not phylogenetically cluster within either of the two currently accepted paramyxoviral subfamilies. It is therefore only distantly related to the only other known genus of reptilian paramyxoviruses, Ferlavirus, which clusters within the Paramyxovirinae subfamily. Clinical and diagnostic aspects associated with Sunshine virus are as yet undescribed. The objective of this paper was to report the clinical presentation, virus isolation, PCR testing and pathology associated with Sunshine virus infection. Clinical records and samples from naturally occurring cases were obtained from two captive snake collections and the archives of a veterinary diagnostic laboratory. The clinical signs that are associated with Sunshine virus infection are localised to the neurorespiratory systems or are non-specific (e.g. lethargy, inappetence). Out of 15 snakes that were infected with Sunshine virus (detected in any organ by either virus isolation or PCR), the virus was isolated from four out of ten (4/10) sampled brains, 3/10 sampled lungs and 2/7 pooled samples of kidney and liver. In these same 15 snakes, PCR was able to successfully detect Sunshine virus in fresh-frozen brain (11/11), kidney (7/8), lung (8/11) and liver (5/8); and various formalin-fixed paraffin-embedded tissues (7/8). During a natural outbreak of Sunshine virus in a collection of 32 snakes, the virus could be detected in five out of 39 combined oral-cloacal swabs that were collected from 23 of these snakes over a 105 day period. All snakes that were infected with Sunshine virus were negative for reovirus and ferlavirus by PCR. Snakes infected with Sunshine virus reliably exhibited hindbrain white matter spongiosis and gliosis with extension to the surrounding grey matter and neuronal necrosis evident in severe cases. Five out of eight infected snakes also exhibited mild bronchointerstitial pneumonia

  19. Crenarchaeal Viruses: Morphotypes and Genomes,

    DEFF Research Database (Denmark)

    Prangishvili, P.; Basta, P.; Garrett, Roger Antony

    2008-01-01

    not been observed among viruses from the other two domains of life, the Bacteria and the Eukarya. Also the sequences of circular and linear genomes of crenarchaeal viruses are remarkable because the vast majority of predicted genes have no homologs in the public sequence databases. Viruses of the...... demonstrated a simple transcriptional pattern with minimal temporal control. The replication of viral genomes has not been studied experimentally. Nevertheless, some plausible predictions about possible replication strategies could be made based on specific features of several viral genomes. The comparative...... genomics studies revealed that crenarchaeal viruses form a distinctive group, unrelated to any other viruses, with a small pool of shared genes and a unique origin, or more likely, multiple origins....

  20. Giant viruses come of age.

    Science.gov (United States)

    Fischer, Matthias G

    2016-06-01

    Viruses with genomes up to a few megabases in length are a common occurrence in nature, even though they have escaped our notice until recently. These giant viruses infect mainly single-celled eukaryotes and isolation efforts concentrating on amoebal hosts alone have spawned hundreds of viral isolates, featuring viruses with previously unseen virion morphologies and the largest known viral genomes and particles. One of the challenges that lie ahead is to analyze and categorize the available data and to establish an approved classification system that reflects the evolutionary relationships and biological properties of these viruses. Extensive sampling of Acanthamoeba-infecting mimiviruses and initial characterization of their virophage parasites have provided a first blueprint of the genetic diversity and composition of a giant virus clade that will facilitate the taxonomic grouping of these fascinating microorganisms. PMID:26999382

  1. Co-infections with Chikungunya Virus and Dengue Virus in Delhi, India

    OpenAIRE

    Chahar, Harendra S; Bharaj, Preeti; Dar, Lalit; Guleria, Randeep; Kabra, Sushil K; Broor, Shobha

    2009-01-01

    Aedes aegypti mosquitoes are common vectors for dengue virus and chikungunya virus. In areas where both viruses cocirculate, they can be transmitted together. During a dengue outbreak in Delhi in 2006, 17 of 69 serum samples were positive for chikungunya virus by reverse transcription–PCR; 6 samples were positive for both viruses.

  2. Ebola Virus Antibodies in Fruit Bats, Bangladesh

    OpenAIRE

    Kevin J Olival; Islam, Ariful; YU, Meng; Anthony, Simon J.; Epstein, Jonathan H.; Khan, Shahneaz Ali; Khan, Salah Uddin; Crameri, Gary; Wang, Lin-Fa; Lipkin, W. Ian; Luby, Stephen P.; Daszak, Peter

    2013-01-01

    To determine geographic range for Ebola virus, we tested 276 bats in Bangladesh. Five (3.5%) bats were positive for antibodies against Ebola Zaire and Reston viruses; no virus was detected by PCR. These bats might be a reservoir for Ebola or Ebola-like viruses, and extend the range of filoviruses to mainland Asia.

  3. Advanced Metamorphic Techniques in Computer Viruses

    OpenAIRE

    Beaucamps, Philippe

    2007-01-01

    Nowadays viruses use polymorphic techniques to mutate their code on each replication, thus evading detection by antiviruses. However detection by emulation can defeat simple polymorphism: thus metamorphic techniques are used which thoroughly change the viral code, even after decryption. We briefly detail this evolution of virus protection techniques against detection and then study the MetaPHOR virus, today's most advanced metamorphic virus.

  4. The IFITMs Inhibit Zika Virus Replication.

    Science.gov (United States)

    Savidis, George; Perreira, Jill M; Portmann, Jocelyn M; Meraner, Paul; Guo, Zhiru; Green, Sharone; Brass, Abraham L

    2016-06-14

    Zika virus has emerged as a severe health threat with a rapidly expanding range. The IFITM family of restriction factors inhibits the replication of a broad range of viruses, including the closely related flaviruses West Nile virus and dengue virus. Here, we show that IFITM1 and IFITM3 inhibit Zika virus infection early in the viral life cycle. Moreover, IFITM3 can prevent Zika-virus-induced cell death. These results suggest that strategies to boost the actions and/or levels of the IFITMs might be useful for inhibiting a broad range of emerging viruses. PMID:27268505

  5. The IFITMs Inhibit Zika Virus Replication

    Directory of Open Access Journals (Sweden)

    George Savidis

    2016-06-01

    Full Text Available Zika virus has emerged as a severe health threat with a rapidly expanding range. The IFITM family of restriction factors inhibits the replication of a broad range of viruses, including the closely related flaviruses West Nile virus and dengue virus. Here, we show that IFITM1 and IFITM3 inhibit Zika virus infection early in the viral life cycle. Moreover, IFITM3 can prevent Zika-virus-induced cell death. These results suggest that strategies to boost the actions and/or levels of the IFITMs might be useful for inhibiting a broad range of emerging viruses.

  6. Defective interfering particles of Sindbis virus do not interfere with the homologous virus obtained from persistently infected BHK cells but do interfere with Semliki Forest virus.

    OpenAIRE

    Weiss, B; Schlesinger, S

    1981-01-01

    Defective interfering particles derived from wild-type Sindbis virus no longer interfere with the infectious virus cloned from BHK cells persistently infected with Sindbis virus for 16 months. These particles do interfere with the replication of Semliki Forest virus.

  7. Oncolytic virus therapy for cancer

    Directory of Open Access Journals (Sweden)

    Goldufsky J

    2013-09-01

    Full Text Available Joe Goldufsky,1 Shanthi Sivendran,3 Sara Harcharik,4 Michael Pan,4 Sebastian Bernardo,4 Richard H Stern,5 Philip Friedlander,4 Carl E Ruby,1,2 Yvonne Saenger,4 Howard L Kaufman1,2 Departments of 1Immunology & Microbiology and 2Surgery, Rush University Medical Center, Chicago IL, USA 3Hematology/Oncology Medical Specialists, Lancaster General Health, Lancaster, PA, USA, and Departments of 4Medical Oncology and 5Radiology, Tisch Cancer Institute, The Mount Sinai School of Medicine, New York, NY, USA Abstract: The use of oncolytic viruses to treat cancer is based on the selection of tropic tumor viruses or the generation of replication selective vectors that can either directly kill infected tumor cells or increase their susceptibility to cell death and apoptosis through additional exposure to radiation or chemotherapy. In addition, viral vectors can be modified to promote more potent tumor cell death, improve the toxicity profile, and/or generate host antitumor immunity. A variety of viruses have been developed as oncolytic therapeutics, including adenovirus, vaccinia virus, herpesvirus, coxsackie A virus, Newcastle disease virus, and reovirus. The clinical development of oncolytic viral therapy has accelerated in the last few years, with several vectors entering clinical trials for a variety of cancers. In this review, current strategies to optimize the therapeutic effectiveness and safety of the major oncolytic viruses are discussed, and a summary of current clinical trials is provided. Further investigation is needed to characterize better the clinical impact of oncolytic viruses, but there are increasing data demonstrating the potential promise of this approach for the treatment of human and animal cancers. Keywords: cancer, gene therapy, oncolytic therapy, virus, treatment

  8. A new looming of Zika virus

    OpenAIRE

    Nirav R. Soni

    2016-01-01

    Zika virus (ZIKV) is a member of the virus family Flaviviridae and the genus Flavivirus, transmitted by daytime-active Aedes mosquitoes, such as A. aegypti. ZIKV will continue to spread and it will be difficult to determine how the virus will spread over time. Sign and symptoms of ZIKAVD (Zika virus disease) were conjunctivitis (red eyes), back pain, birth defect-abnormal brain development known as microcephaly and it is diagnosed through PCR (polymerase chain reaction) and virus isolation fr...

  9. Towards the Epidemiological Modeling of Computer Viruses

    OpenAIRE

    Xiaofan Yang; Lu-Xing Yang

    2012-01-01

    Epidemic dynamics of computer viruses is an emerging discipline aiming to understand the way that computer viruses spread on networks. This paper is intended to establish a series of rational epidemic models of computer viruses. First, a close inspection of some common characteristics shared by all typical computer viruses clearly reveals the flaws of previous models. Then, a generic epidemic model of viruses, which is named as the SLBS model, is proposed. Finally, diverse generalizations of ...

  10. Virus-membrane interactions: spectroscopic studies.

    OpenAIRE

    Datema, K.P.

    1987-01-01

    In this thesis some new aspects of the infection process of nonenveloped viruses are reported. The interaction of a rod-shaped (TMV) and three spherical (CCMV, BMV, SBMV) plant viruses, of the filamentous bacteriophage M13, and of their coat proteins with membranes have been investigated. A comparison is made between the infection mechanisms of these non-enveloped viruses.1 EFFECT OF PLANT VIRUSES ON MEMBRANESAll plant viruses studied interact with membranes. This is demonstrated by turbidity...

  11. Advanced Virus Monitoring and Analysis System

    OpenAIRE

    Fauzi Adi Rafrastara; Faizal M. A.

    2011-01-01

    This research proposed an architecture and a system which able to monitor the virus behavior and classify them as a traditional or polymorphic virus. Preliminary research was conducted to get the current virus behavior and to find the certain parameters which usually used by virus to attack the computer target. Finally, “test bed environment” is used to test our system by releasing the virus in a real environment, and try to capture their behavior, and followed by generating the conclusion th...

  12. Detection of Junk Instructions in Computer Viruses

    OpenAIRE

    2008-01-01

    The techniques employed by viruses to avoid detection by antivirus scanners are becoming increasingly advanced. One technique commonly used by viruses to evade detection is polymorphism. The level of polymorphism in a virus indicates its ability to create different forms of itself. The use of junk instructions is a common technique to increase the level of polymorphism in a virus. Junk instructions are machine code instructions with no other function than to alter the appearance of a virus. J...

  13. Animal viruses, radiation, repair mechanisms, and cancer

    International Nuclear Information System (INIS)

    Effects of radiation on animal viruses are reviewed in terms of repair mechanisms and their possible relationship to virus transformation and carcinogenesis. Repair mechanisms are reviewed under the headings; multiplicity reactivation, photoreactivation, host-cell reactivation (dark repair), and uv reactivation. Other topics discussed are: transformation of cells in vitro by irradiated viruses, oncogenicity of virus-transformed cells in vivo, and possible role of repair mechanisms in virus transformation and oncogenesis

  14. RNA recombination in animal and plant viruses.

    OpenAIRE

    Lai, M M

    1992-01-01

    An increasing number of animal and plant viruses have been shown to undergo RNA-RNA recombination, which is defined as the exchange of genetic information between nonsegmented RNAs. Only some of these viruses have been shown to undergo recombination in experimental infection of tissue culture, animals, and plants. However, a survey of viral RNA structure and sequences suggests that many RNA viruses were derived form homologous or nonhomologous recombination between viruses or between viruses ...

  15. Zika Virus: the Latest Newcomer

    OpenAIRE

    Saiz, Juan-Carlos; Vázquez-Calvo, Ángela; Blázquez, Ana B.; Merino-Ramos, Teresa; Escribano-Romero, Estela; Martín-Acebes, Miguel A.

    2016-01-01

    Since the beginning of this century, humanity has been facing a new emerging, or re-emerging, virus threat almost every year: West Nile, Influenza A, avian flu, dengue, Chikungunya, SARS, MERS, Ebola, and now Zika, the latest newcomer. Zika virus (ZIKV), a flavivirus transmitted by Aedes mosquitoes, was identified in 1947 in a sentinel monkey in Uganda, and later on in humans in Nigeria. The virus was mainly confined to the African continent until it was detected in south-east Asia the 1980’s...

  16. Zika virus: the latest newcomer

    OpenAIRE

    Juan-Carlos eSaiz; Angela eVazquez-Calvo; Ana Belen Blazquez; Teresa eMerino-Ramos; Estela eEscribano-Romero; Martín-Acebes, Miguel A.

    2016-01-01

    Since the beginning of this century, humanity has been facing a new emerging, or re-emerging, virus threat almost every year: West Nile, Influenza A, avian flu, dengue, Chikungunya, SARS, MERS, Ebola, and now Zika, the latest newcomer. Zika virus (ZIKV), a flavivirus transmitted by Aedes mosquitoes, was identified in 1947 in a sentinel monkey in Uganda, and later on in humans in Nigeria. The virus was mainly confined to the African continent until it was detected in south-east Asia the 1980´s...

  17. Marburg Virus Reverse Genetics Systems

    Directory of Open Access Journals (Sweden)

    Kristina Maria Schmidt

    2016-06-01

    Full Text Available The highly pathogenic Marburg virus (MARV is a member of the Filoviridae family and belongs to the group of nonsegmented negative-strand RNA viruses. Reverse genetics systems established for MARV have been used to study various aspects of the viral replication cycle, analyze host responses, image viral infection, and screen for antivirals. This article provides an overview of the currently established MARV reverse genetic systems based on minigenomes, infectious virus-like particles and full-length clones, and the research that has been conducted using these systems.

  18. New insights of Sacbrood virus

    Institute of Scientific and Technical Information of China (English)

    Mingxiao; Ma

    2014-01-01

    <正>Over the last several years,major efforts have been expended to study viral infection of honeybees mainly due to colony losses around the world(Allen M,et al.,1996).It seems that honeybees are infected with numerous viruses mounting to 18so far.Infection may be asymptomatic but could still have adverse effects on the bee and may even cause death resulting in colony collapse.Sacbrood virus(SBV)is the most widely distributed of all honey bee viruses.

  19. MODEL DINAMIKA VIRUS HIV DAN VIRUS MUTAN DENGAN SISTEM IMUN

    OpenAIRE

    Ikhsan, Laode Muhammad

    2014-01-01

    Model of the dynamics of HIV infection with the mutan virus and the Immune System is a mathematical model that describes the interactions between healthy T cells, in infected cells, and the HIV virus. The models obtained three equilibrium points, which has an endemic equilibrium point and the point of equilibrium without the disease. By doing stability analysis, the stability of the equilibrium point has obtained depends on the model of the basic reproduction number (R01 dan R02). For the...

  20. Zika virus infections.

    Science.gov (United States)

    de Laval, F; Leparc-Goffart, I; Meynard, J-B; Daubigny, H; Simon, F; Briolant, S

    2016-05-01

    Since its discovery in 1947 in Uganda, the Zika virus (ZIKV) remained in the shadows emerging in 2007 in Micronesia, where hundreds of dengue-like syndromes were reported. Then, in 2013-2014, it was rife in French Polynesia, where the first neurological effects were observed. More recently, its arrival in Brazil was accompanied by an unusually high number of children with microcephaly born to mothers infected with ZIKV during the first trimester of pregnancy. In 2016, the World Health Organization declared ZIKV infection to be a public health emergency and now talks about a ZIKV pandemic. This review aims to summarize the current knowledge about ZIKV infection, successively addressing its transmission, epidemiology, clinical aspects, diagnosis, treatment, and prevention before discussing some perspectives. PMID:27412976

  1. Cryptovirology: Virus Approach

    Directory of Open Access Journals (Sweden)

    Shivale Saurabh Anandrao

    2011-08-01

    Full Text Available Traditionally, "Cryptography" is a benediction to information processing and communications, it helps people to store information securely and the private communications over long distances. Cryptovirology is the study of applications of cryptography to build the malicious software. It is an investigation, how modern cryptographic tools and paradigms can be used to strengthen, develop and improve new malicious software attacks. Cryptovirology attacks have been categorized as : give malware enhanced privacy andbe more robust against reverse-engineering, secondly give the attacker enhanced anonymity while communicating with deployed malware. This paper presents the idea of ``Cryptovirology'' which introduce a twist on how cryptography can also be used offensively. Being offensive means, it can be used to mount extortion based attacks that cause loss of access to information, loss of confidentiality, and information leakage, tasks which cryptography usually prevents. Also analyze threats and attacks that misuse of cryptography can cause when combined with fraudulent software (viruses, Trojans. Public-keycryptography is very essential for the attacks that based on cryptovirology. This paper also suggest some of the countermeasures, mechanisms to cope with and prevent such attacks. Even if the attackers actions on the host machine are being monitored, it still cannot be proven beyond reasonable doubt that he or she is the attacker; and it is an “originator-concealing attack”. Evidence should be collected from the “author’s own system which was used for the attack”. These attacks have implications on how the use ofcryptographic tools and techniques should be audited and managed in general purpose computing environments, and imply that access to the cryptographic tools should be in well control of the system(such as API routines. The experimental virus would demonstrate how cryptographic packages can be packed into a small space, which may

  2. Adeno-associated virus: from defective virus to effective vector

    Directory of Open Access Journals (Sweden)

    Gonçalves Manuel AFV

    2005-05-01

    Full Text Available Abstract The initial discovery of adeno-associated virus (AAV mixed with adenovirus particles was not a fortuitous one but rather an expression of AAV biology. Indeed, as it came to be known, in addition to the unavoidable host cell, AAV typically needs a so-called helper virus such as adenovirus to replicate. Since the AAV life cycle revolves around another unrelated virus it was dubbed a satellite virus. However, the structural simplicity plus the defective and non-pathogenic character of this satellite virus caused recombinant forms to acquire centre-stage prominence in the current constellation of vectors for human gene therapy. In the present review, issues related to the development of recombinant AAV (rAAV vectors, from the general principle to production methods, tropism modifications and other emerging technologies are discussed. In addition, the accumulating knowledge regarding the mechanisms of rAAV genome transduction and persistence is reviewed. The topics on rAAV vectorology are supplemented with information on the parental virus biology with an emphasis on aspects that directly impact on vector design and performance such as genome replication, genetic structure, and host cell entry.

  3. Transfection by DNAs of avian erythroblastosis virus and avian myelocytomatosis virus strain MC29.

    OpenAIRE

    Copeland, N G; Cooper, G M

    1980-01-01

    Chicken embryo fibroblasts and NIH 3T3 mouse cells were transformable by DNAs of chicken cells infected with avian myelocytomatosis virus strain MC29 or with avian erythroblastosis virus. Transfection of chicken cells appeared to require replication of MC29 or avian erythroblastosis virus in the presence of a nontransforming helper virus. In contrast, NIH 3T3 cells transformed by MC29 or avian erythroblastosis virus DNA contained only replication-defective transforming virus genomes.

  4. Varicella-zoster virus vaccine DNA differs from the parental virus DNA.

    OpenAIRE

    Ecker, J R; Hyman, R W

    1981-01-01

    The DNAs of a varicella-zoster virus vaccine and its parental virus were compared by CsCl buoyant density centrifugation and restriction enzyme cleavage analysis. The varicella-zoster virus vaccine DNA showed a heterogeneous buoyant profile and altered restriction enzyme cleavage patterns. These changed properties are probably the result of the accumulation of virus containing defective varicella-zoster virus DNA during extensive cell culture passage of the vaccine virus.

  5. Neoplastic transformation of chimpanzee cells induced by adenovirus type 12--simian virus 40 hybrid virus.

    OpenAIRE

    Rhim, J S; Trimmer, R; Arnstein, P; Huebner, R J

    1981-01-01

    The adenovirus 12--simian virus 40 hybrid virus produced neoplastic transformation of chimpanzee skin fibroblasts in vitro. The transformed fibroblasts showed morphological alteration and became permanent lines. The transformed cells contained both adenovirus 12 and simian virus 40 large tumor antigens and were virus producers. However at passage 9, one line (WES) was found to be a nonproducer, producing neither infectious virus nor virus-specific antigen detectable by the complement fixation...

  6. A recombinant rabies virus expressing vesicular stomatitis virus glycoprotein fails to protect against rabies virus infection

    OpenAIRE

    Foley, Heather D.; McGettigan, James P.; Siler, Catherine A.; Dietzschold, Bernhard; Schnell, Matthias J.

    2000-01-01

    To investigate the importance of the rabies virus (RV) glycoprotein (G) in protection against rabies, we constructed a recombinant RV (rRV) in which the RV G ecto- and transmembrane domains were replaced with the corresponding regions of vesicular stomatitis virus (VSV) glycoprotein (rRV-VSV-G). We were able to recover rRV-VSV-G and found that particle production was equal to rRV. However, the budding of the chimeric virus was delayed and infectious titers were red...

  7. Archaeal viruses of the sulfolobales

    DEFF Research Database (Denmark)

    Erdmann, Susanne; Garrett, Roger Antony

    2015-01-01

    Infection of archaea with phylogenetically diverse single viruses, performed in different laboratories, has failed to activate spacer acquisition into host CRISPR loci. The first successful uptake of archaeal de novo spacers was observed on infection of Sulfolobus solfataricus P2 with an environm......Infection of archaea with phylogenetically diverse single viruses, performed in different laboratories, has failed to activate spacer acquisition into host CRISPR loci. The first successful uptake of archaeal de novo spacers was observed on infection of Sulfolobus solfataricus P2 with an...... CRISPR loci of Sulfolobus species from a second coinfecting conjugative plasmid or virus (Erdmann and Garrett, Mol Microbiol 85:1044-1056, 2012; Erdmann et al. Mol Microbiol 91:900-917, 2014). Here we describe, firstly, the isolation of archaeal virus mixtures from terrestrial hot springs and the...

  8. Zika virus: An international emergency?

    Science.gov (United States)

    Palomo, Adolfo Martinez

    2016-05-01

    This Viewpoint discusses the World Health Organization's Declaration on 1 February 2016 that the epidemic infection caused by the Zika virus is a public health emergency of international concern - the basis of the decision and controversy surrounding it. PMID:26911655

  9. Oncolytic viruses in radiation oncology

    International Nuclear Information System (INIS)

    Oncolytic viruses are investigational cancer treatments. They are currently being assessed as single agents or in combination with standard therapies such as external beam radiotherapy - a DNA damaging agent that is a standard of care for many tumour types. Preclinical data indicate that combinations of oncolytic viruses and radiation therapy are promising, showing additional or synergistic antitumour effects in in vitro and in vivo studies. This interaction has the potential to be multifaceted: viruses may act as radiosensitizing agents, but radiation may also enhance viral oncolysis by increasing viral uptake, replication, gene expression and cell death (apoptosis, autophagy or necrosis) in irradiated cells. Phase I and II clinical trials investigating combinations of viruses and radiation therapy have been completed, paving the way for ongoing phase III studies. The aim of this review is to focus on the therapeutic potential of these combinations and to highlight their mechanistic bases, with particular emphasis on the role of the DNA damage response.

  10. Dengue Virus Infection in Africa

    OpenAIRE

    Amarasinghe, Ananda; Kuritsky, Joel N.; Letson, G. William; Margolis, Harold S

    2011-01-01

    Reported incidence of dengue has increased worldwide in recent decades, but little is known about its incidence in Africa. During 1960–2010, a total of 22 countries in Africa reported sporadic cases or outbreaks of dengue; 12 other countries in Africa reported dengue only in travelers. The presence of disease and high prevalence of antibody to dengue virus in limited serologic surveys suggest endemic dengue virus infection in all or many parts of Africa. Dengue is likely underrecognized and u...

  11. Hepatitis virus vaccines: present status.

    OpenAIRE

    Krugman, S.

    1982-01-01

    During the past decade there has been extraordinary progress toward the development of vaccines for the prevention of type A and type B hepatitis. The successful propagation of hepatitis A virus in cell culture in 1979 was followed by the preparation of experimental live attenuated hepatitis A vaccines that have been shown to induce antibody in marmosets and chimpanzees and protect immunized marmosets against challenge with hepatitis A virus. The first human immunization trials will begin in ...

  12. Hendra Virus Re-visited

    Institute of Scientific and Technical Information of China (English)

    Hume Field

    2009-01-01

    Hendra virus, a novel member of the family Paramyxovirus that has emerged from bats in Australia, causes fatal disease in livestock and humans. Eleven spillover events have been identified since the first description of the virus in 1994, resulting in a total of 37 equine cases and six human cases. All human cases have been attributed to exposure to infected horses; there is no evidence of bat-to-human or human-to-human transmission. Low infectivity and a high case fatality rate are features of Hendra virus infection in both horses and humans. The temporal pattern of spillover events suggests seasonal factors (plausibly be environmental, biological or ecological) as the proximate triggers for spillover. Minimisation of the future occurrence and impact of Hendra virus infections requires an understanding of the ecology of flying foxes, of virus infection dynamics in flying foxes, and of the factors that promote spillover. Management strategies seek to minimize the opportunity for effective contact between bats and horses, and limit potential horse-to-horse and horse-to-human transmission. Incomplete knowledge of the ecology of the virus, of the proximate factors associated with spillover, and the inherent difficulties of effectively managing wild populations, preclude a management approach targeted at bats.

  13. Zika Virus Infection and Zika Fever: Frequently Asked Questions

    Science.gov (United States)

    ... Frequently asked questions Updated: 25 March 2016 ABOUT ZIKA What is Zika virus infection? Zika virus infection is caused by ... possible to characterize the disease better. How is Zika virus transmitted? Zika virus is transmitted to people ...

  14. The IFITMs Inhibit Zika Virus Replication

    OpenAIRE

    George Savidis; Jill M. Perreira; Jocelyn M. Portmann; Paul Meraner; Zhiru Guo; Sharone Green; Abraham L. Brass

    2016-01-01

    Zika virus has emerged as a severe health threat with a rapidly expanding range. The IFITM family of restriction factors inhibits the replication of a broad range of viruses, including the closely related flaviruses West Nile virus and dengue virus. Here, we show that IFITM1 and IFITM3 inhibit Zika virus infection early in the viral life cycle. Moreover, IFITM3 can prevent Zika-virus-induced cell death. These results suggest that strategies to boost the actions and/or levels of the IFITMs mig...

  15. Advances in Research of Garlic Virus Diseases

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Garlic virus infection is an important disease which affects garlic production,with the increasing years of planting,harm of virus is serious year by year,which seriously affect yield and quality of garlic.In order to know the garlic virus effectively,the paper reviewed the research situation of several important garlic virus in virus species,origin,distribution,host range,symptom,route of transmission,classification,genome and detection technique and the prevention technology of garlic viruses.At the same ...

  16. The Mode of Net-Virus Actions

    Institute of Scientific and Technical Information of China (English)

    ShanXiuming; LiYing; JiaoJian; LiuYang; RenYong; QiuBen; CaoYiqun

    2004-01-01

    The computer network is not only of benefit to people, but also helpful for the spreading of viruses. The net-viruses spread more widely and rapidly than the traditional viruses, and network has become the major path of the virus spreading. The author analyzes the mode of the net-virus spreading, including E-mail spreading, positive scanning spreading and through-server spreading. Then some defense strategies in the anti-virus field are introduced, and some countermeasures of the net computer users are discussed.

  17. Production of cattle immunotolerant to bovine viral diarrhea virus.

    OpenAIRE

    McClurkin, A W.; Littledike, E T; Cutlip, R C; Frank, G H; Coria, M F; Bolin, S R

    1984-01-01

    Inoculation of bovine virus diarrhea virus into 58 to 125 day old fetuses of bovine virus diarrhea virus seropositive pregnant cows, or inoculation of bovine virus diarrhea virus into seronegative cows 42 to 114 days pregnant, may produce clinically normal calves which are persistently infected with the specific isolate of bovine virus diarrhea virus yet seronegative to the homologous and heterologous isolates. Reinoculation of these persistently infected cattle with their homologous isolate ...

  18. Presence and Distribution of Tobacco Viruses in Montenegro

    OpenAIRE

    Jelena Zindović; Nataša Dukić; Aleksandra Bulajić; Jelena Latinović; Ivana Đekić; Bojan Duduk; Branka Krstić

    2007-01-01

    Seven important tobacco viruses were investigated in Montenegro in 2005: Tobacco Mosaic Virus (TMV), Tomato Spotted Wilt Virus (TSWV), Cucumber Mosaic Virus (CMV), Potato Virus Y (PVY), Alfalfa Mosaic Virus (AMV), Tobacco Ring Spot Virus (TRSV) and Potato Virus X(PVX). This investigation included sample collection from four tobacco growing regions in Montenegro and their serological testing by DAS-ELISA test. Presence of different strains of PVY was investigated as well using DAS ELISA test w...

  19. Peptide inhibitors of dengue virus and West Nile virus infectivity

    Directory of Open Access Journals (Sweden)

    Garry Robert F

    2005-06-01

    Full Text Available Abstract Viral fusion proteins mediate cell entry by undergoing a series of conformational changes that result in virion-target cell membrane fusion. Class I viral fusion proteins, such as those encoded by influenza virus and human immunodeficiency virus (HIV, contain two prominent alpha helices. Peptides that mimic portions of these alpha helices inhibit structural rearrangements of the fusion proteins and prevent viral infection. The envelope glycoprotein (E of flaviviruses, such as West Nile virus (WNV and dengue virus (DENV, are class II viral fusion proteins comprised predominantly of beta sheets. We used a physio-chemical algorithm, the Wimley-White interfacial hydrophobicity scale (WWIHS 1 in combination with known structural data to identify potential peptide inhibitors of WNV and DENV infectivity that target the viral E protein. Viral inhibition assays confirm that several of these peptides specifically interfere with target virus entry with 50% inhibitory concentration (IC50 in the 10 μM range. Inhibitory peptides similar in sequence to domains with a significant WWIHS scores, including domain II (IIb, and the stem domain, were detected. DN59, a peptide corresponding to the stem domain of DENV, inhibited infection by DENV (>99% inhibition of plaque formation at a concentrations of 99% inhibition at

  20. Virus elimination in acute lymphocytic choriomeningitis virus infection. Correlation with virus-specific delayed-type hypersensitivity rather than cytotoxicity

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Volkert, M; Bro-Jørgensen, K

    1983-01-01

    The immunological effector mechanism responsible for the elimination of virus in murine acute non-fatal extracranial lymphocytic choriomeningitis virus infection was studied. In this infection virus clearance is generally regarded as the result of a direct action of virus-specific cytotoxic T cells...... (Tc cells) on virus-producing target cells in the infected mouse. However, by manipulating the antiviral immune response by pretreatment with various doses of cyclophosphamide, we found lack of correlation between Tc-cell activity and the clearance of virus. In contrast, we observed a conspicuous...... correlation between the host's ability to mount a virus-specific delayed-type hypersensitivity (DTH) response and its capacity to combat virus. Moreover, pretreatment with silica and carrageenan prolonged viraemia without impairment of the peak Tc-cell response. These findings indicate that Tc cells have...

  1. Ebola virus: recommendations

    CERN Multimedia

    CERN Medical Service

    2014-01-01

    The CERN Medical Service has been closely following, in particular via the WHO, the development of the Ebola virus outbreak currently affecting some African countries. This infectious disease may be passed on through direct contact with the bodily fluids of a sick person.   Based on the recommendations of the WHO and the two Host States, Switzerland and France, as updated on their respective websites, so far there has been no ban on travel to the countries concerned. However, unless it is absolutely essential, you are advised not to visit any of the countries affected by Ebola (Guinea, Republic of Sierra Leone, Liberia, Nigeria). The two Host States have established an alert system, and a check is carried out on departure from the airports of those countries. It is strongly recommended that you contact the Medical Service if you are travelling to those countries. We remind you to observe the basic rules of hygiene such as frequent hand washing, whatever your destination. The Medical Service is...

  2. Hepatitis B virus replication

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Hepadnaviruses, including human hepatitis B virus (HBV), replicate through reverse transcription of an RNA intermediate, the pregenomic RNA (pgRNA). Despite this kinship to retroviruses, there are fundamental differences beyond the fact that hepadnavirions contain DNA instead of RNA. Most peculiar is the initiation of reverse transcription: it occurs by protein-priming, is strictly committed to using an RNA hairpin on the pgRNA,ε, as template, and depends on cellular chaperones;moreover, proper replication can apparently occur only in the specialized environment of intact nucleocapsids.This complexity has hampered an in-depth mechanistic understanding. The recent successful reconstitution in the test tube of active replication initiation complexes from purified components, for duck HBV (DHBV),now allows for the analysis of the biochemistry of hepadnaviral replication at the molecular level. Here we review the current state of knowledge at all steps of the hepadnaviral genome replication cycle, with emphasis on new insights that turned up by the use of such cellfree systems. At this time, they can, unfortunately,not be complemented by three-dimensional structural information on the involved components. However, at least for the s RNA element such information is emerging,raising expectations that combining biophysics with biochemistry and genetics will soon provide a powerful integrated approach for solving the many outstanding questions. The ultimate, though most challenging goal,will be to visualize the hepadnaviral reverse transcriptase in the act of synthesizing DNA, which will also have strong implications for drug development.

  3. Hepatitis B virus morphogenesis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The hepatitis B virus (HBV) particle consists of an envelope containing three related surface proteins and probably lipid and an icosahedral nucleocapsid of approximately 30 nm diameter enclosing the viral DNA genome and DNA polymerase. The capsid is formed in the cytosol of the infected cell during packaging of an RNA pregenome replication complex by multiple copies of a 21-kDa C protein. The capsid gains the ability to bud during synthesis of the viral DNA genome by reverse transcription of the pregenome in the lumen of the particle. The three envelope proteins S,M, and L shape a complex transmembrane fold at the endoplasmic reticulum, and form disulfide-linked homoand heterodimers. The transmembrane topology of a fraction of the large envelope protein L changes posttranslationally, therefore, the N terminal domain of L (preS) finally appears on both sides of the membrane.During budding at an intracellular membrane, a short linear domain in the cytosolic preS region interacts with binding sites on the capsid surface. The virions are subsequently secreted into the blood. In addition, the surface proteins can bud in the absence of capsids and form subviral lipoprotein particles of 20 nm diameter which are also secreted.

  4. Oncolytic virus therapies.

    Science.gov (United States)

    Buonaguro, Franco Maria; Tornesello, Maria Lina; Izzo, Francesco; Buonaguro, Luigi

    2012-11-01

    Oncolytic virus (OV) therapy currently represents one of the most promising approaches to cancer treatment for their dual anticancer mechanisms: direct lysis of cancer cells (oncolytic feature) and activation of the immunosystem (cancer vaccine aspect). The latter demonstrates the advantage of a multi-target approach against multiple tumor-associated antigens. Since the 2005 SFDA (the Chinese FDA) approval for the clinical use of Oncorine™, the first human OV-based cancer treatment, more than 200 patents have been filed worldwide and several Phase I/II studies have been conducted. This patent review analyzes patents and clinical studies of the most promising OV products to highlight the pros and cons of this innovative anticancer approach, which is currently being tested in several cancers (i.e., hepatocellular carcinoma, melanoma and glioblastoma) by systemic as well as intratumoral injection. Clinical results, although effective only for a limited period of time, are encouraging. Combined treatments with radio or chemotherapeutic protocols are also in progress. PMID:24236929

  5. Immune based computer virus detection approaches

    Institute of Scientific and Technical Information of China (English)

    TAN Ying; ZHANG Pengtao

    2013-01-01

    The computer virus is considered one of the most horrifying threats to the security of computer systems worldwide.The rapid development of evasion techniques used in virus causes the signature based computer virus detection techniques to be ineffective.Many novel computer virus detection approaches have been proposed in the past to cope with the ineffectiveness,mainly classified into three categories:static,dynamic and heuristics techniques.As the natural similarities between the biological immune system (BIS),computer security system (CSS),and the artificial immune system (AIS) were all developed as a new prototype in the community of anti-virus research.The immune mechanisms in the BIS provide the opportunities to construct computer virus detection models that are robust and adaptive with the ability to detect unseen viruses.In this paper,a variety of classic computer virus detection approaches were introduced and reviewed based on the background knowledge of the computer virus history.Next,a variety of immune based computer virus detection approaches were also discussed in detail.Promising experimental results suggest that the immune based computer virus detection approaches were able to detect new variants and unseen viruses at lower false positive rates,which have paved a new way for the anti-virus research.

  6. Autophagic machinery activated by dengue virus enhances virus replication

    International Nuclear Information System (INIS)

    Autophagy is a cellular response against stresses which include the infection of viruses and bacteria. We unravel that Dengue virus-2 (DV2) can trigger autophagic process in various infected cell lines demonstrated by GFP-LC3 dot formation and increased LC3-II formation. Autophagosome formation was also observed under the transmission electron microscope. DV2-induced autophagy further enhances the titers of extracellular and intracellular viruses indicating that autophagy can promote viral replication in the infected cells. Moreover, our data show that ATG5 protein is required to execute DV2-induced autophagy. All together, we are the first to demonstrate that DV can activate autophagic machinery that is favorable for viral replication

  7. [Bats and Viruses: complex relationships].

    Science.gov (United States)

    Rodhain, E

    2015-10-01

    With more than 1 200 species, bats and flying foxes (Order Chiroptera) constitute the most important and diverse order of Mammals after Rodents. Many species of bats are insectivorous while others are frugivorous and few of them are hematophagous. Some of these animals fly during the night, others are crepuscular or diurnal. Some fly long distances during seasonal migrations. Many species are colonial cave-dwelling, living in a rather small home range while others are relatively solitary. However, in spite of the importance of bats for terrestrial biotic communities and ecosystem ecology, the diversity in their biology and lifestyles remain poorly known and underappreciated. More than sixty viruses have been detected or isolated in bats; these animals are therefore involved in the natural cycles of many of them. This is the case, for instance, of rabies virus and other Lyssavirus (Family Rhabdoviridae), Nipah and Hendra viruses (Paramyxoviridae), Ebola and Marburg viruses (Filoviridae), SARS-CoV and MERS-CoV (Coronaviridae). For these zoonotic viruses, a number of bat species are considered as important reservoir hosts, efficient disseminators or even directly responsible of the transmission. Some of these bat-borne viruses cause highly pathogenic diseases while others are of potential significance for humans and domestic or wild animals; so, bats are an important risk in human and animal public health. Moreover, some groups of viruses developed through different phylogenetic mechanisms of coevolution between viruses and bats. The fact that most of these viral infections are asymptomatic in bats has been observed since a long time but the mechanisms of the viral persistence are not clearly understood. The various bioecology of the different bat populations allows exchange of virus between migrating and non-migrating conspecific species. For a better understanding of the role of bats in the circulation of these viral zoonoses, epidemiologists must pay attention to

  8. Coping with Computer Viruses: General Discussion and Review of Symantec Anti-Virus for the Macintosh.

    Science.gov (United States)

    Primich, Tracy

    1992-01-01

    Discusses computer viruses that attack the Macintosh and describes Symantec AntiVirus for Macintosh (SAM), a commercial program designed to detect and eliminate viruses; sample screen displays are included. SAM is recommended for use in library settings as well as two public domain virus protection programs. (four references) (MES)

  9. Dot immunobinding assay for simultaneous detection of specific immunoglobulin G antibodies to measles virus, mumps virus, and rubella virus.

    OpenAIRE

    F. Condorelli; Ziegler, T.

    1993-01-01

    A dot immunobinding assay was used to detect antibodies to measles virus, mumps virus, and rubella virus antigens. Filter paper soaked with serum or whole blood was directly applied to the antigen-coated nitrocellulose sheets. The test was easy to perform, and its results agreed very well with those obtained by standard enzyme immunoassay.

  10. Droplet Microfluidics for Virus Discovery

    Science.gov (United States)

    Rotem, Assaf; Cockrell, Shelley; Guo, Mira; Pipas, James; Weitz, David

    2012-02-01

    The ability to detect, isolate, and characterize an infectious agent is important for diagnosing and curing infectious diseases. Detecting new viral diseases is a challenge because the number of virus particles is often low and/or localized to a small subset of cells. Even if a new virus is detected, it is difficult to isolate it from clinical or environmental samples where multiple viruses are present each with very different properties. Isolation is crucial for whole genome sequencing because reconstructing a genome from fragments of many different genomes is practically impossible. We present a Droplet Microfluidics platform that can detect, isolate and sequence single viral genomes from complex samples containing mixtures of many viruses. We use metagenomic information about the sample of mixed viruses to select a short genomic sequence whose genome we are interested in characterizing. We then encapsulate single virions from the same sample in picoliter volume droplets and screen for successful PCR amplification of the sequence of interest. The selected drops are pooled and their contents sequenced to reconstruct the genome of interest. This method provides a general tool for detecting, isolating and sequencing genetic elements in clinical and environmental samples.

  11. Scientists Try to Stop Another Deadly Virus

    Science.gov (United States)

    ... 158128.html Scientists Try to Stop Another Deadly Virus Junin, an Ebola-like disease in Argentina, has ... drug could offer a new weapon against the virus that causes Argentine hemorrhagic fever -- a potentially fatal ...

  12. A Literature Review of Zika Virus.

    Science.gov (United States)

    Plourde, Anna R; Bloch, Evan M

    2016-07-01

    Zika virus is a mosquitoborne flavivirus that is the focus of an ongoing pandemic and public health emergency. Previously limited to sporadic cases in Africa and Asia, the emergence of Zika virus in Brazil in 2015 heralded rapid spread throughout the Americas. Although most Zika virus infections are characterized by subclinical or mild influenza-like illness, severe manifestations have been described, including Guillain-Barre syndrome in adults and microcephaly in babies born to infected mothers. Neither an effective treatment nor a vaccine is available for Zika virus; therefore, the public health response primarily focuses on preventing infection, particularly in pregnant women. Despite growing knowledge about this virus, questions remain regarding the virus's vectors and reservoirs, pathogenesis, genetic diversity, and potential synergistic effects of co-infection with other circulating viruses. These questions highlight the need for research to optimize surveillance, patient management, and public health intervention in the current Zika virus epidemic. PMID:27070380

  13. Duck Virus Enteritis - A Contingency Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Duck plague, also known as duck virus enteritis (DVE) is a highly contagious, extremely deadly epizootic virus with a potential for devastating continental...

  14. Influenza Type A Viruses and Subtypes

    Science.gov (United States)

    ... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... this? Submit What's this? Submit Button Past Newsletters Influenza Type A Viruses Language: English Español Recommend ...

  15. About Epstein-Barr Virus (EBV)

    Science.gov (United States)

    ... Search The CDC Epstein-Barr Virus and Infectious Mononucleosis Note: Javascript is disabled or is not supported ... Mono Home About Epstein-Barr Virus About Infectious Mononucleosis For Healthcare Providers Laboratory Testing References & Resources About ...

  16. Bats and Viruses: a Brief Review

    Institute of Scientific and Technical Information of China (English)

    Lin-Fa Wang

    2009-01-01

    Bats, probably the most abundant, diverse and geographically dispersed vertebrates on earth, have recently been shown to be the reservoir hosts of a number of emerging viruses responsible for severe human and livestock disease outbreaks. Flying foxes have been demonstrated to be the natural reservoir for Hendra and Nipah viruses. Evidence supporting the possibility of bats as potential reservoirs for SARS coronavirus (SARS-CoV) and Ebola virus has also been reported. The recent discovery of these viruses and other viruses occurring naturally in the bat population provides a unique insight into a diverse pool of potentially emergent and pathogenic viruses. The factors which influence the ability of zoonotic viruses to effectively cross the species barrier from bats to other animal populations are poorly understood. A brief review is provided here on the recently emerged bat viruses and on current and future strategies for research in this area.

  17. West Nile Virus Cases, 2006-present

    Data.gov (United States)

    U.S. Department of Health & Human Services — This dataset contains positive cases of West Nile virus found in humans by county of residence, 2006-present. Humans usually become infected with West Nile virus by...

  18. FAQ: West Nile Virus and Dead Birds

    Science.gov (United States)

    ... Education Public Service Videos West Nile Virus & Dead Birds Recommend on Facebook Tweet Share Compartir On this ... dead bird sightings to local authorities. How do birds get infected with West Nile virus? West Nile ...

  19. Porcine Reproductive and Respiratory Syndrome Virus (PRRSV)

    DEFF Research Database (Denmark)

    Kvisgaard, Lise Kirstine

    This PhD thesis presents the diversity of Porcine Reproductive and Respiratory Syndrome viruses (PRRSV) circulating in the Danish pig population. PRRS is a disease in pigs caused by the PRRS virus resulting in reproductive failures in sows and gilts and respiratory diseases in pigs . Due to genetic...... heterogeneity, PRRSV is divided into two genotypes, Type 1 and Type 2. Type 1 PRRS viruses are further divided into at least 3 subtypes. The virus evolves rapidly and reports of high pathogenic variants of both Type 1 and Type 2 appearing in Europe, North America, and Asia have been reported within recent years...... viruses showed both a higher diversity to the other Danish viruses and to the vaccine strain and one virus harbored the largest deletion in NSP2 reported in Danish Type 2 PRRSV. Manuscript IV is focusing on an experimental infection study in pigs with a Type 2 PRRS virus causing significant clinical...

  20. New Dengue Virus Vaccine Shows Promise

    Science.gov (United States)

    ... nih.gov/medlineplus/news/fullstory_157799.html New Dengue Virus Vaccine Shows Promise Research may also aid ... 16, 2016 (HealthDay News) -- An experimental vaccine against dengue -- the mosquito-borne virus behind a very painful ...

  1. Dengue Virus May Bolster Zika's Attack

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_159534.html Dengue Virus May Bolster Zika's Attack Prior exposure to ... 23, 2016 (HealthDay News) -- Prior exposure to the dengue fever virus may increase the severity of Zika ...

  2. Control of virus diseases of berry crops.

    Science.gov (United States)

    Martin, Robert R; Tzanetakis, Ioannis E

    2015-01-01

    Virus control in berry crops starts with the development of plants free of targeted pathogens, usually viruses, viroids, phytoplasmas, and systemic bacteria, through a combination of testing and therapy. These then become the top-tier plants in certification programs and are the source from which all certified plants are produced, usually after multiple cycles of propagation. In certification schemes, efforts are made to produce plants free of the targeted pathogens to provide plants of high health status to berry growers. This is achieved using a systems approach to manage virus vectors. Once planted in fruit production fields, virus control shifts to disease control where efforts are focused on controlling viruses or virus complexes that result in disease. In fruiting fields, infection with a virus that does not cause disease is of little concern to growers. Virus control is based on the use of resistance and tolerance, vector management, and isolation. PMID:25591882

  3. Nucleocytoplasmic Shuttling of Influenza A Virus Proteins

    Directory of Open Access Journals (Sweden)

    Jing Li

    2015-05-01

    Full Text Available Influenza viruses transcribe and replicate their genomes in the nuclei of infected host cells. The viral ribonucleoprotein (vRNP complex of influenza virus is the essential genetic unit of the virus. The viral proteins play important roles in multiple processes, including virus structural maintenance, mediating nucleocytoplasmic shuttling of the vRNP complex, virus particle assembly, and budding. Nucleocytoplasmic shuttling of viral proteins occurs throughout the entire virus life cycle. This review mainly focuses on matrix protein (M1, nucleoprotein (NP, nonstructural protein (NS1, and nuclear export protein (NEP, summarizing the mechanisms of their nucleocytoplasmic shuttling and the regulation of virus replication through their phosphorylation to further understand the regulation of nucleocytoplasmic shuttling in host adaptation of the viruses.

  4. General properties of grapevine viruses occurring in Hungary

    Directory of Open Access Journals (Sweden)

    Eszter Cseh

    2012-03-01

    Full Text Available The past fifty years important advances have been made in the field of grapevine virus research, including characterization of pathogens and control measurements. Still the occurrence of Grapevine fanleaf virus (GFLV, Arabis mosaic virus (ArMV, Tomato black ring virus (TBRV, Grapevine chrome mosaic virus (GCMV, Alfalfa mosaic virus (AMV, Grapevine Bulgarian latent virus (GBLV, Grapevine fleck virus (GFkV, Grapevine leafroll- associated viruses (GLRaV1-4, Grapevine virus A (GVA, Grapevine virus B (GVB and Grapevine rupestris stem pitting- associated virus (GRSPaV have been reported in Hungary and characterized by conventional methods as woody indexing, herbaceous indexing and serological methods. Among grapevine viruses the Grapevine line pattern virus (GLPV seems to be uncial; because it was reported only in Hungary. Causal agents of several grapevine diseases, like enation, vein necrosis and vein mosaic remained undiscovered. These virus-like diseases occurred only sporadically, without economic importance.

  5. Evolution of Computer Virus Concealment and Anti-Virus Techniques: A Short Survey

    CERN Document Server

    Rad, Babak Bashari; Ibrahim, Suhaimi

    2011-01-01

    This paper presents a general overview on evolution of concealment methods in computer viruses and defensive techniques employed by anti-virus products. In order to stay far from the anti-virus scanners, computer viruses gradually improve their codes to make them invisible. On the other hand, anti-virus technologies continually follow the virus tricks and methodologies to overcome their threats. In this process, anti-virus experts design and develop new methodologies to make them stronger, more and more, every day. The purpose of this paper is to review these methodologies and outline their strengths and weaknesses to encourage those are interested in more investigation on these areas.

  6. Citrus tristeza virus-host interactions

    OpenAIRE

    Dawson, William O.; Garnsey, Stephen M.; Satyanarayana eTatineni; Folimonova, Svetlana Y.; Scott J Harper; S eGowda

    2013-01-01

    Citrus tristeza virus (CTV) is a phloem-limited virus whose natural host range is restricted to citrus and related species. Although the virus has killed millions of trees, almost destroying whole industries, and continually limits production in many citrus growing areas, most isolates are mild or symptomless in most of their host range. There is little understanding of how the virus causes severe disease in some citrus and none in others. Movement and distribution of CTV differs considerably...

  7. Inhibition of interferon signaling by dengue virus

    OpenAIRE

    Muñoz-Jordán, Jorge L.; Sánchez-Burgos, Gilma G.; Laurent-Rolle, Maudry; García-Sastre, Adolfo

    2003-01-01

    Dengue virus is a worldwide-distributed mosquito-borne flavivirus with a positive strand RNA genome. Its transcribed polyprotein is cleaved by host- and virus-encoded peptidases into 10 proteins, some of which are of unknown function. Although dengue virus-infected cells seem to be resistant to the antiviral action of IFN, the viral products that mediate this resistance are unknown. Therefore, we have analyzed the ability of the 10 dengue virus-encoded proteins to antagonize the IFN response....

  8. Viruses and prions of Saccharomyces cerevisiae

    OpenAIRE

    Wickner, Reed B.; Fujimura, Tsutomu; Esteban, Rosa

    2013-01-01

    Saccharomyces cerevisiae has been a key experimental organism for the study of infectious diseases, including dsRNA viruses, ssRNA viruses, and prions. Studies of the mechanisms of virus and prion replication, virus structure, and structure of the amyloid filaments that are the basis of yeast prions have been at the forefront of such studies in these classes of infectious entities. Yeast has been particularly useful in defining the interactions of the infectious elements with cellular compone...

  9. Viruses and Sialic Acids: Rules of Engagement

    OpenAIRE

    Neu, Ursula; Bauer, Johannes; Stehle, Thilo

    2011-01-01

    Viral infections are initiated by specific attachment of a virus particle to receptors at the surface of the host cell. For many viruses, these receptors are glycans that are linked to either a protein or a lipid. Glycans terminating in sialic acid and its derivatives serve as receptors for a large number of viruses, including several human pathogens. In combination with glycan array analyses, structural analyses of complexes of viruses with sialylated oligosaccharides have provided insights ...

  10. RNA virus genomics: a world of possibilities

    OpenAIRE

    Edward C Holmes

    2009-01-01

    The increasing availability of complete genome sequences of RNA viruses has the potential to shed new light on fundamental aspects of their biology. Here, I use case studies of 3 RNA viruses to explore the impact of genomic sequence data, with particular emphasis on influenza A virus. Notably, the studies of RNA virus genomics undertaken to date largely focused on issues of evolution and epidemiology, and they have given these disciplines new impetus. However, genomic data have so far made fe...

  11. Inhibition of Interferons by Ectromelia Virus

    OpenAIRE

    Smith, Vincent P.; Alcami, Antonio

    2002-01-01

    Ectromelia virus (EV) is an orthopoxvirus (OPV) that causes mousepox, a severe disease of laboratory mice. Mousepox is a useful model of OPV infection because EV is likely to be a natural mouse pathogen, unlike its close relatives vaccinia virus (VV) and variola virus. Several studies have highlighted the importance of mouse interferons (IFNs) in resistance to and recovery from EV infection, but little is known of the anti-IFN strategies encoded by the virus itself. We have determined that 12...

  12. Characteristics of Filoviridae: Marburg and Ebola Viruses

    Science.gov (United States)

    Beer, Brigitte; Kurth, Reinhard; Bukreyev, Alexander

    Filoviruses are enveloped, nonsegmented negative-stranded RNA viruses. The two species, Marburg and Ebola virus, are serologically, biochemically, and genetically distinct. Marburg virus was first isolated during an outbreak in Europe in 1967, and Ebola virus emerged in 1976 as the causative agent of two simultaneous outbreaks in southern Sudan and northern Zaire. Although the main route of infection is known to be person-to-person transmission by intimate contact, the natural reservoir for filoviruses still remains a mystery.

  13. The interferon sensitivity of selected porcine viruses.

    OpenAIRE

    Derbyshire, J. B.

    1989-01-01

    The objective of this study was to compare the sensitivity of 11 porcine viruses to the antiviral effects of porcine interferon-alpha in serum from piglets which had been infected 19 h previously with transmissible gastroenteritis virus, and of porcine interferon-beta prepared in PK-15 cells by induction with polyinosinic:polycytidylic acid, in yield reduction assays in pig kidney cells which were treated with interferon before virus challenge, and both before and after virus challenge. The m...

  14. Novel hemagglutinin-based influenza virus inhibitors

    OpenAIRE

    Shen, Xintian; Zhang, Xuanxuan; Liu, Shuwen

    2013-01-01

    Influenza virus has caused seasonal epidemics and worldwide pandemics, which caused tremendous loss of human lives and socioeconomics. Nowadays, only two classes of anti-influenza drugs, M2 ion channel inhibitors and neuraminidase inhibitors respectively, are used for prophylaxis and treatment of influenza virus infection. Unfortunately, influenza virus strains resistant to one or all of those drugs emerge frequently. Hemagglutinin (HA), the glycoprotein in influenza virus envelope, plays a c...

  15. [Zika virus, an emerging threat].

    Science.gov (United States)

    Salinas, Sara; Foulongne, Vincent; Loustalot, Fabien; Fournier-Wirth, Chantal; Molès, Jean-Pierre; Briant, Laurence; Nagot, Nicolas; Van de Perre, Philippe; Simonin, Yannick

    2016-04-01

    Zika virus, discovered in 1947, is particularly publicized because of its involvement in a major epidemic that began in 2015 and which epicenter is located in Latin America, mainly in Brazil. In the majority of cases (70-80 %) the infection is asymptomatic, however in some patients, moderate fever, skin rash, conjunctivitis and myalgia may occur. More alarming, neurological complications are reported, in particular cases of microcephaly probably resulting from the infection of women in the first or second trimester of pregnancy. Moreover, Guillain-Barré syndromes have also been identified in patients whose infection was confirmed. The extent of the current outbreak reveals the very primitive state of knowledge about the pathophysiology of this virus. Thus, a global effort is being undertaken in order to quickly characterize the molecular interaction of the virus with human cells, but also to develop specific diagnostic assays and vaccinal approaches. PMID:27137695

  16. Virus Dynamics on Starlike Graphs

    CERN Document Server

    Becker, Thealexa; Kontorovich, Leonid Aryeh; Miller, Steven J; Ravikumar, Pradeep; Shen, Karen

    2011-01-01

    The field of epidemiology has presented fascinating and relevant questions for mathematicians, primarily concerning the spread of viruses in a community. The importance of this research has greatly increased over time as its applications have expanded to also include studies of electronic and social networks and the spread of information and ideas. We study virus propagation on a non-linear hub and spoke graph (which models well many airline networks). We determine the long-term behavior as a function of the cure and infection rates, as well as the number of spokes n. For each n we prove the existence of a critical threshold relating the two rates. Below this threshold, the virus always dies out; above this threshold, all non-trivial initial conditions iterate to a unique non-trivial steady state. We end with some generalizations to other networks.

  17. Hepatitis Virus Infections in Poultry.

    Science.gov (United States)

    Yugo, Danielle M; Hauck, Ruediger; Shivaprasad, H L; Meng, Xiang-Jin

    2016-09-01

    Viral hepatitis in poultry is a complex disease syndrome caused by several viruses belonging to different families including avian hepatitis E virus (HEV), duck hepatitis B virus (DHBV), duck hepatitis A virus (DHAV-1, -2, -3), duck hepatitis virus Types 2 and 3, fowl adenoviruses (FAdV), and turkey hepatitis virus (THV). While these hepatitis viruses share the same target organ, the liver, they each possess unique clinical and biological features. In this article, we aim to review the common and unique features of major poultry hepatitis viruses in an effort to identify the knowledge gaps and aid the prevention and control of poultry viral hepatitis. Avian HEV is an Orthohepevirus B in the family Hepeviridae that naturally infects chickens and consists of three distinct genotypes worldwide. Avian HEV is associated with hepatitis-splenomegaly syndrome or big liver and spleen disease in chickens, although the majority of the infected birds are subclinical. Avihepadnaviruses in the family of Hepadnaviridae have been isolated from ducks, snow geese, white storks, grey herons, cranes, and parrots. DHBV evolved with the host as a noncytopathic form without clinical signs and rarely progressed to chronicity. The outcome for DHBV infection varies by the host's ability to elicit an immune response and is dose and age dependent in ducks, thus mimicking the pathogenesis of human hepatitis B virus (HBV) infections and providing an excellent animal model for human HBV. DHAV is a picornavirus that causes a highly contagious virus infection in ducks with up to 100% flock mortality in ducklings under 6 wk of age, while older birds remain unaffected. The high morbidity and mortality has an economic impact on intensive duck production farming. Duck hepatitis virus Types 2 and 3 are astroviruses in the family of Astroviridae with similarity phylogenetically to turkey astroviruses, implicating the potential for cross-species infections between strains. Duck astrovirus (DAstV) causes

  18. Characterization of Ebola Virus Entry by Using Pseudotyped Viruses: Identification of Receptor-Deficient Cell Lines

    OpenAIRE

    Wool-Lewis, Rouven J.; Bates, Paul

    1998-01-01

    Studies analyzing Ebola virus replication have been severely hampered by the extreme pathogenicity of this virus. To permit analysis of the host range and function of the Ebola virus glycoprotein (Ebo-GP), we have developed a system for pseudotyping these glycoproteins into murine leukemia virus (MLV). This pseudotyped virus, MLV(Ebola), can be readily concentrated to titers which exceed 5 × 106 infectious units/ml and is effectively neutralized by antibodies specific for Ebo-GP. Analysis of ...

  19. Virus-Like Vesicle-Based Therapeutic Vaccine Vectors for Chronic Hepatitis B Virus Infection

    OpenAIRE

    Tracy D Reynolds; Buonocore, Linda; Rose, Nina F.; Rose, John K.; Robek, Michael D.

    2015-01-01

    More than 500,000 people die each year from the liver diseases that result from chronic hepatitis B virus (HBV) infection. Therapeutic vaccines, which aim to elicit an immune response capable of controlling the virus, offer a potential new treatment strategy for chronic hepatitis B. Recently, an evolved, high-titer vaccine platform consisting of Semliki Forest virus RNA replicons that express the vesicular stomatitis virus glycoprotein (VSV G) has been described. This platform generates virus...

  20. Antigen mimicry involving measles virus hemagglutinin and human respiratory syncytial virus nucleoprotein.

    OpenAIRE

    Norrby, E; Sheshberadaran, H; Rafner, B

    1986-01-01

    Intergenic antigenic relationships between measles virus and respiratory syncytial (RS) virus-specific structural components were studied by using monoclonal antibodies. Of 75 monoclonal antibodies against these components, only one, an anti-measles virus hemagglutinin monoclonal antibody, cross-reacted. Immunofluorescence analysis of measles virus- and RS virus-infected cells with this monoclonal antibody showed qualitatively different staining patterns which indicated that the antigen invol...

  1. Influenza A virus targets a cGAS-independent STING pathway that controls enveloped RNA viruses

    OpenAIRE

    Holm, Christian K.; Rahbek, Stine H.; Gad, Hans Henrik; Bak, Rasmus O.; Jakobsen, Martin R; Jiang, Zhaozaho; Hansen, Anne Louise; Jensen, Simon K.; Sun, Chenglong; Thomsen, Martin K.; Laustsen, Anders; Nielsen, Camilla G.; Severinsen, Kasper; Xiong, Yingluo; Burdette, Dara L.

    2016-01-01

    Stimulator of interferon genes (STING) is known be involved in control of DNA viruses but has an unexplored role in control of RNA viruses. During infection with DNA viruses STING is activated downstream of cGAMP synthase (cGAS) to induce type I interferon. Here we identify a STING-dependent, cGAS-independent pathway important for full interferon production and antiviral control of enveloped RNA viruses, including influenza A virus (IAV). Further, IAV interacts with STING through its conserve...

  2. More Effective Purifying Selection on RNA Viruses than in DNA Viruses

    OpenAIRE

    Hughes, Austin L.; Hughes, Mary Ann K.

    2007-01-01

    Analysis of the pattern of nucleotide diversity in 222 independent viral sequence datasets showed the prevalence of purifying selection. In spite of the higher mutation rate of RNA viruses, our analyses revealed stronger evidence of the action of purifying selection in RNA viruses than in DNA viruses. The ratio of nonsynonymous to synonymous nucleotide diversity was significantly lower in RNA viruses than in DNA viruses, indicating that nonsynonymous mutations have been removed at a greater r...

  3. Emerging viruses in the genus Comovirus

    Czech Academy of Sciences Publication Activity Database

    Petrzik, Karel; Koloniuk, Igor

    2010-01-01

    Roč. 40, č. 2 (2010), s. 290-292. ISSN 0920-8569 R&D Projects: GA ČR GA522/07/0053 Institutional research plan: CEZ:AV0Z50510513 Keywords : Capsid proteins * plant virus * Radish mosaic virus * Turnip ringspot virus Subject RIV: EE - Microbiology, Virology Impact factor: 1.693, year: 2010

  4. Emerging foodborne and agriculture-related viruses

    Science.gov (United States)

    Viruses rapidly evolve and can emerge in unpredictable ways. Mechanisms by which food-borne viruses may enter human populations and become pathogens is discussed. It is known the majority of viruses emerge from zoonotic animal reservoirs, often by adapting and infecting intermediate hosts, such as ...

  5. Ebola Virus Persistence in Semen Ex Vivo

    OpenAIRE

    Fischer, Robert J.; Judson, Seth; Miazgowicz, Kerri; Bushmaker, Trent; Munster, Vincent J.

    2016-01-01

    On March 20, 2015, a case of Ebola virus disease was identified in Liberia that most likely was transmitted through sexual contact. We assessed the efficiency of detecting Ebola virus in semen samples by molecular diagnostics and the stability of Ebola virus in ex vivo semen under simulated tropical conditions.

  6. Viruses infecting Brassicas in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Špak, Josef; Kubelková, Darina

    Bonn : DPG and BBA, 2002. s. 50. [Joint Conference of the International Working Groups on Legume Viruses and Vegetale Viruses /1./. 04.08.2002-09.08.2002, Bonn] Institutional research plan: CEZ:AV0Z5051902 Keywords : plant pathology * viruses Subject RIV: EE - Microbiology, Virology

  7. Virus infections of honeybees Apis Mellifera

    Directory of Open Access Journals (Sweden)

    Giuseppina Tantillo

    2015-09-01

    Full Text Available The health and vigour of honeybee colonies are threatened by numerous parasites (such as Varroa destructor and Nosema spp. and pathogens, including viruses, bacteria, protozoa. Among honeybee pathogens, viruses are one of the major threats to the health and wellbeing of honeybees and cause serious concern for researchers and beekeepers. To tone down the threats posed by these invasive organisms, a better understanding of bee viral infections will be of crucial importance in developing effective and environmentally benign disease control strategies. Here we summarize recent progress in the understanding of the morphology, genome organization, transmission, epidemiology and pathogenesis of eight honeybee viruses: Deformed wing virus (DWV and Kakugo virus (KV; Sacbrood virus (SBV; Black Queen cell virus (BQCV; Acute bee paralysis virus (ABPV; Kashmir bee virus (KBV; Israeli Acute Paralysis Virus (IAPV; Chronic bee paralysis virus (CBPV. The review has been designed to provide researchers in the field with updated information about honeybee viruses and to serve as a starting point for future research.

  8. Lagos bat virus in Kenya.

    Science.gov (United States)

    Kuzmin, Ivan V; Niezgoda, Michael; Franka, Richard; Agwanda, Bernard; Markotter, Wanda; Beagley, Janet C; Urazova, Olga Y; Breiman, Robert F; Rupprecht, Charles E

    2008-04-01

    During lyssavirus surveillance, 1,221 bats of at least 30 species were collected from 25 locations in Kenya. One isolate of Lagos bat virus (LBV) was obtained from a dead Eidolon helvum fruit bat. The virus was most similar phylogenetically to LBV isolates from Senegal (1985) and from France (imported from Togo or Egypt; 1999), sharing with these viruses 100% nucleoprotein identity and 99.8 to 100% glycoprotein identity. This genome conservancy across space and time suggests that LBV is well adapted to its natural host species and that populations of reservoir hosts in eastern and western Africa have sufficient interactions to share pathogens. High virus concentrations, in addition to being detected in the brain, were detected in the salivary glands and tongue and in an oral swab, suggesting that LBV is transmitted in the saliva. In other extraneural organs, the virus was generally associated with innervations and ganglia. The presence of infectious virus in the reproductive tract and in a vaginal swab implies an alternative opportunity for transmission. The isolate was pathogenic for laboratory mice by the intracerebral and intramuscular routes. Serologic screening demonstrated the presence of LBV-neutralizing antibodies in E. helvum and Rousettus aegyptiacus fruit bats. In different colonies the seroprevalence ranged from 40 to 67% and 29 to 46% for E. helvum and R. aegyptiacus, respectively. Nested reverse transcription-PCR did not reveal the presence of viral RNA in oral swabs of bats in the absence of brain infection. Several large bat roosts were identified in areas of dense human populations, raising public health concerns for the potential of lyssavirus infection. PMID:18305130

  9. Hepatitis C Virus Genotypes

    Directory of Open Access Journals (Sweden)

    Kayhan Azadmanesh

    2005-09-01

    Full Text Available IntroductionHepatitis C virus (HCV is an important cause of chronic liver disease. HCV causes 20% of acute hepatitis cases, 70% of all chronic hepatitis cases, 40% of all cases of liver cirrhosis, 60% of hepatocellular carcinomas, and 30% of liver transplants in Europe(1. It is also recognized as the leading cause of liver transplantation in the world(2. Only 20% of infected individuals will recover from this viral infection, while the rest become chronically infected(3. While the majority of chronically infected individuals never exhibit symptoms, approximately 10-30% of these patients will eventually develop cirrhosis or hepatocellular carcinoma, both of which are associated with significant morbidity and mortality(4.More than 170 million people worldwide are chronically infected with HCV. According to WHO report in 2002, chronic liver diseases were responsible for 1.4 million deaths, including 796,000 due to cirrhosis and 616,000 due to primary liver cancer. At least 20% of these deaths are probably attributable to HCV infection- more than 280,000 deaths(5, 6. The prevalence of chronic HCV infection in general population varies greatly in different parts of the world, being estimated between 0.1 and 5%, with a peak prevalence of 20- 25% in Egypt. HCV prevalence seems to be less than 1% in Iran, which is much lower than most of the neighboring countries(7. HCV was the first virus discovered by molecular cloning method without the direct use of biologic or biophysical methods. This was accomplished by extracting, copying into cDNA, and cloning all the nucleic acid from the plasma of a chimpanzee infected with non- A, non-B hepatitis by contaminated factor XIII concentrate(8. The HCV genome is a positive-sense, singlestranded RNA genome approximately 10 kb long. It has marked similarities to those of members of the genera Pestivirus and Flavivirus. Different HCV isolates from around the world show substantial nucleotide sequence variability

  10. Activation analysis in virus research

    International Nuclear Information System (INIS)

    Nucleic acids contain various amounts of trace elements. With divalent cations tobacco mosaic virus ribonucleic acid (TMV-RNA) undergoes changes in optical density at 258 mμ in both optical rotation and in sedimentation behaviour. These changes suggested the transformation from a random coil to a more orderly configuration. The connection between trace elements and the biological activity of TMV-RNA has been investigated. However, the relationship between metal ions and the virus infection process has not received much attention. This subject is discussed briefly in this paper. 8 refs

  11. Immunochemical characterization of the O antigens of two Proteus strains, O8-related antigen of Proteus mirabilis 12 B-r and O2-related antigen of Proteus genomospecies 5/6 12 B-k, infecting a hospitalized patient in Poland.

    Science.gov (United States)

    Drzewiecka, Dominika; Shashkov, Alexander S; Arbatsky, Nikolay P; Knirel, Yuriy A

    2016-05-01

    A hospitalized 73-year-old woman was infected with a Proteus mirabilis strain, 12 B-r, isolated from the place of injection of a blood catheter. Another strain, 12 B-k, recognized as Proteus genomospecies 5 or 6, was isolated from the patient's faeces, which was an example of a nosocomial infection rather than an auto-infection. Serological investigation using ELISA and Western blotting showed that strain 12 B-k from faeces belonged to the Proteus O2 serogroup. Strain 12 B-r from the wound displayed cross-reactions with several Proteus O serogroups due to common epitopes on the core or O-specific parts of the lipopolysaccharide. Studies of the isolated 12 B-r O-specific polysaccharide by NMR spectroscopy revealed its close structural similarity to that of Proteus O8. The only difference in 12 B-r was the presence of an additional GlcNAc-linked phosphoethanolamine residue, which creates a putative epitope responsible for the cross-reactivity with Pt. mirabilis O16. The new O-antigen form could appear as a result of adaptation of the bacterium to a changing environment. On the basis of the data obtained, we suggest division of the O8 serogroup into two subgroups: O8a for strains of various Proteus species that have been previously classified into the O8 serogroup, and O8a,b for Pt. mirabilis 12 B-r, where 'a' is a common epitope and 'b' is a phosphoethanolamine-associated epitope. These findings further confirm serological and structural heterogeneity of O antigens of Proteus strains isolated lately from patients in Poland. PMID:26959528

  12. Beet mosaic virus: epidemiology and damage

    OpenAIRE

    Dusi, A.N.

    1999-01-01

    Overview:The aim of the studies described in this thesis was to obtain a thorough understanding of the main factors determining the spread of a potyvirus in a high plant density crop. The factors studied included the relationships between virus, host and vector, the spread of the virus around an initial virus source consisting of one or more infected plants, the spread of the virus by the prevailing aphid population, and the effect of plant density on the spread of the virus. A time-save samp...

  13. Radiation Inactivation of Viruses in Infected Products

    International Nuclear Information System (INIS)

    Full text: The effects of gamma radiation on foot-and-mouth disease virus in vitro and in situ have been studied. The data so far obtained show that a dose of 2 Mrad is required to inactivate virus in infected animal carcasses. But the dose may adversely affect the organoleptic quality of the meat. Experiments in vitro and in situ are necessary to study the effects of ionizing radiation on other viruses, such as rinderpest, swine fever and African swine fever-viruses, associated with animal products. Radiation may offer a possible means of eliminating the virus titre in many animal products and solve consequent quarantine problems. (author)

  14. Expanding networks of RNA virus evolution

    OpenAIRE

    Koonin Eugene V; Dolja Valerian V

    2012-01-01

    Abstract In a recent BMC Evolutionary Biology article, Huiquan Liu and colleagues report two new genomes of double-stranded RNA (dsRNA) viruses from fungi and use these as a springboard to perform an extensive phylogenomic analysis of dsRNA viruses. The results support the old scenario of polyphyletic origin of dsRNA viruses from different groups of positive-strand RNA viruses and additionally reveal extensive horizontal gene transfer between diverse viruses consistent with the network-like r...

  15. Viruses, dendritic cells and the lung

    Directory of Open Access Journals (Sweden)

    Graham Barney S

    2001-06-01

    Full Text Available Abstract The interaction between viruses and dendritic cells (DCs is varied and complex. DCs are key elements in the development of a host response to pathogens such as viruses, but viruses have developed survival tactics to either evade or diminish the immune system that functions to kill and eliminate these micro-organisms. In the present review we summarize current concepts regarding the function of DCs in the immune system, our understanding of how viruses alter DC function to attenuate both the virus-specific and global immune response, and how we may be able to exploit DC function to prevent or treat viral infections.

  16. A new looming of Zika virus

    Directory of Open Access Journals (Sweden)

    Nirav R. Soni

    2016-05-01

    Full Text Available Zika virus (ZIKV is a member of the virus family Flaviviridae and the genus Flavivirus, transmitted by daytime-active Aedes mosquitoes, such as A. aegypti. ZIKV will continue to spread and it will be difficult to determine how the virus will spread over time. Sign and symptoms of ZIKAVD (Zika virus disease were conjunctivitis (red eyes, back pain, birth defect-abnormal brain development known as microcephaly and it is diagnosed through PCR (polymerase chain reaction and virus isolation from blood samples.

  17. Presence and distribution of economically important potato viruses in Montenegro

    OpenAIRE

    Jelena Zindović

    2011-01-01

    The research was carried out, in the period 2002-2004 in order to determine the presence and distribution of potato viruses at 12 different locations and on 9 different potato varieties grown in Montenegro. The research included collecting of samples in seed potato crops and testing of six economically important potato viruses: Potato leaf roll virus (PLRV), Potato virus Y (PVY), Potato virus X (PVX), Potato virus S (PVS), Potato virus A (PVA) i Potato viru...

  18. Oncogenes and RNA splicing of human tumor viruses

    OpenAIRE

    Ajiro, Masahiko; Zheng, Zhi-Ming

    2014-01-01

    Approximately 10.8% of human cancers are associated with infection by an oncogenic virus. These viruses include human papillomavirus (HPV), Epstein–Barr virus (EBV), Merkel cell polyomavirus (MCV), human T-cell leukemia virus 1 (HTLV-1), Kaposi's sarcoma-associated herpesvirus (KSHV), hepatitis C virus (HCV) and hepatitis B virus (HBV). These oncogenic viruses, with the exception of HCV, require the host RNA splicing machinery in order to exercise their oncogenic activities, a strategy that a...

  19. Identification of Potato Virus Y Strains in Tobacco Crops

    OpenAIRE

    Jelena Zindović; Janoš Berenji; Milena Pauković; Ivana Đekić; Aleksandra Bulajić; Branka Krstić

    2007-01-01

    Five viruses: Potato Virus Y (PVY), Tomato Spotted Wilt Virus, Cucumber Mosaic Virus, Tobacco Mosaic Virus and Alfalfa Mosaic Virus, of which PVY was predominant, were detected by serological testing of tobacco samples collected from many localities in Vojvodina in 2006. Viruses are the most important pathogens in tobacco and PVY causes considerable economic damages all over the world. A PVY population comprises several different strain groups, strain subgroups and recombinant strains. Among ...

  20. Method for detecting viruses in aerosols.

    Science.gov (United States)

    Wallis, C; Melnick, J L; Rao, V C; Sox, T E

    1985-11-01

    A simple method with poliovirus as the model was developed for recovering human enteric viruses from aerosols. Filterite filters (pore size, 0.45 micron; Filterite Corp., Timonium, Md.) moistened with glycine buffer (pH 3.5) were used for adsorbing the aerosolized virus. No virus passed the filter, even with air flow rates of 100 liters/min. Virus recovery from the filter was achieved by rapid elution with 800 ml of glycine buffer, pH 10. The virus in the primary eluate was reconcentrated by adjusting the pH to 3.5, adding AlCl3 to 0.0005 M, collecting the virus on a 0.25-micron-pore Filerite disk (diameter, 25 mm) and and eluting with 6 ml of buffer, pH 10. With this method, virus could be detected regularly in aerosols produced by flushing when 3 X 10(8) PFU of poliovirus were present in the toilet bowl. Poliovirus-containing fecal material from two of four infants who had recently received oral polio vaccine also yielded virus in the aerosols when feces containing 2.4 X 10(7) to 4.5 X 10(7) PFU of virus had been added to the toilet bowl. Persons infected with a variety of natural enteric viruses are known to excrete this amount of virus in their daily stools. PMID:3004329

  1. Sensitiveness of viruses to gamma radiation

    International Nuclear Information System (INIS)

    The sensitiveness of viruses to gamma rays was compared using eight viruses suspended with low concentration in drinking water, and four viruses present in high concentrations in tissue culture medium. The results show that the following factors are responsible for the resistance of viruses to gamma rays: 1. type of virus: the specific radiation resistance varied considerably; in general, there was a closer correlation with the general resistance of the virus to chemico-physical influences than with the type of nucleic acid of the virus examined; 2. medium of suspension and state of aggregation: high protein content and lyophilisation increased the resistance to gamma rays widely; 3. virus concentration: the virus reduction by a factor of 10 in suspensions with high virus concentration needed a higher radiation dose compared with suspensions of low virus content. All the results demonstrate the kinetics of inactivation to be a 1st order reaction. The increase of temperature to 410C did not show any significant influence. (orig.)

  2. Comparative analysis of chrysanthemum transcriptome in response to three RNA viruses: Cucumber mosaic virus, Tomato spotted wilt virus and Potato virus X.

    Science.gov (United States)

    Choi, Hoseong; Jo, Yeonhwa; Lian, Sen; Jo, Kyoung-Min; Chu, Hyosub; Yoon, Ju-Yeon; Choi, Seung-Kook; Kim, Kook-Hyung; Cho, Won Kyong

    2015-06-01

    The chrysanthemum is one of popular flowers in the world and a host for several viruses. So far, molecular interaction studies between the chrysanthemum and viruses are limited. In this study, we carried out a transcriptome analysis of chrysanthemum in response to three different viruses including Cucumber mosaic virus (CMV), Tomato spotted wilt virus (TSWV) and Potato virus X (PVX). A chrysanthemum 135K microarray derived from expressed sequence tags was successfully applied for the expression profiles of the chrysanthemum at early stage of virus infection. Finally, we identified a total of 125, 70 and 124 differentially expressed genes (DEGs) for CMV, TSWV and PVX, respectively. Many DEGs were virus specific; however, 33 DEGs were commonly regulated by three viruses. Gene ontology (GO) enrichment analysis identified a total of 132 GO terms, and of them, six GO terms related stress response and MCM complex were commonly identified for three viruses. Several genes functioning in stress response such as chitin response and ethylene mediated signaling pathway were up-regulated indicating their involvement in establishment of host immune system. In particular, TSWV infection significantly down-regulated genes related to DNA metabolic process including DNA replication, chromatin organization, histone modification and cytokinesis, and they are mostly targeted to nucleosome and MCM complex. Taken together, our comparative transcriptome analysis revealed several genes related to hormone mediated viral stress response and DNA modification. The identified chrysanthemums genes could be good candidates for further functional study associated with resistant to various plant viruses. PMID:25904110

  3. Emerging influenza virus: A global threat

    Indian Academy of Sciences (India)

    M Khanna; P Kumar; K Choudhary; B Kumar; V K Vijayan

    2008-11-01

    Since 1918, influenza virus has been one of the major causes of morbidity and mortality, especially among young children. Though the commonly circulating strain of the virus is not virulent enough to cause mortality, the ability of the virus genome to mutate at a very high rate may lead to the emergence of a highly virulent strain that may become the cause of the next pandemic. Apart from the influenza virus strain circulating in humans (H1N1 and H3N2), the avian influenza H5N1 H7 and H9 virus strains have also been reported to have caused human infections, H5N1 H7 and H9 have shown their ability to cross the species barrier from birds to humans and further replicate in humans. This review addresses the biological and epidemiological aspects of influenza virus and efforts to have a control on the virus globally.

  4. Expanding networks of RNA virus evolution

    Directory of Open Access Journals (Sweden)

    Koonin Eugene V

    2012-06-01

    Full Text Available Abstract In a recent BMC Evolutionary Biology article, Huiquan Liu and colleagues report two new genomes of double-stranded RNA (dsRNA viruses from fungi and use these as a springboard to perform an extensive phylogenomic analysis of dsRNA viruses. The results support the old scenario of polyphyletic origin of dsRNA viruses from different groups of positive-strand RNA viruses and additionally reveal extensive horizontal gene transfer between diverse viruses consistent with the network-like rather than tree-like mode of viral evolution. Together with the unexpected discoveries of the first putative archaeal RNA virus and a RNA-DNA virus hybrid, this work shows that RNA viral genomics has major surprises to deliver. See research article: http://www.biomedcentral.com/1471-2148/12/91

  5. Molecular patterns of avian influenza A viruses

    Institute of Scientific and Technical Information of China (English)

    KOU Zheng; LEI FuMin; WANG ShengYue; ZHOU YanHong; LI TianXian

    2008-01-01

    Avian influenza A viruses could get across the species barrier and be fatal to humans. Highly patho-genic avian influenza H5N1 virus was an example. The mechanism of interspecies transmission is not clear as yet. In this research, the protein sequences of 237 influenza A viruses with different subtypes were transformed into pseudo-signals. The energy features were extracted by the method of wavelet packet decomposition and used for virus classification by the method of hierarchical clustering. The clustering results showed that five patterns existed in avian influenza A viruses, which associated with the phenotype of interspecies transmission, and that avian viruses with patterns C and E could across species barrier and those with patterns A, B and D might not have the abilities. The results could be used to construct an early warning system to predict the transmissibility of avian influenza A viruses to humans.

  6. Molecular characterization of Indonesia avian influenza virus

    Directory of Open Access Journals (Sweden)

    N.L.P.I. Dharmayanti

    2005-06-01

    Full Text Available Avian influenza outbreaks in poultry have been reported in Java island since August 2003. A total of 14 isolates of avian influenza virus has been isolated from October 2003 to October 2004. The viruses have been identified as HPAI H5N1 subtype. All of them were characterized further at genetic level and also for their pathogenicity. Phylogenetic analysis showed all of the avian influenza virus isolates were closely related to avian influenza virus from China (A/Duck/China/E319-2/03(H5N1. Molecular basis of pathogenicity in HA cleavage site indicated that the isolates of avian influenza virus have multiple basic amino acid (B-X-B-R indicating that all of the isolates representing virulent avian influenza virus (highly pathogenic avian influenza virus.

  7. A Literature Review of Zika Virus

    Science.gov (United States)

    Bloch, Evan M.

    2016-01-01

    Zika virus is a mosquitoborne flavivirus that is the focus of an ongoing pandemic and public health emergency. Previously limited to sporadic cases in Africa and Asia, the emergence of Zika virus in Brazil in 2015 heralded rapid spread throughout the Americas. Although most Zika virus infections are characterized by subclinical or mild influenza-like illness, severe manifestations have been described, including Guillain-Barre syndrome in adults and microcephaly in babies born to infected mothers. Neither an effective treatment nor a vaccine is available for Zika virus; therefore, the public health response primarily focuses on preventing infection, particularly in pregnant women. Despite growing knowledge about this virus, questions remain regarding the virus’s vectors and reservoirs, pathogenesis, genetic diversity, and potential synergistic effects of co-infection with other circulating viruses. These questions highlight the need for research to optimize surveillance, patient management, and public health intervention in the current Zika virus epidemic. PMID:27070380

  8. Viruses and phytoplasmas infecting strawberry

    Czech Academy of Sciences Publication Activity Database

    Špak, Josef; Fránová, Jana

    Jokioinen : MTT Agrifood Research, 2008. s. 68. [COST863, WG2 and WG3 Joint SGM "Plant Health in Changing Environment . 19.05.2008-20.05.2008, Jokioinen] Institutional research plan: CEZ:AV0Z50510513 Keywords : plant disease * viruses * strawberry Subject RIV: EE - Microbiology, Virology

  9. Oncolytic viruses as anticancer vaccines

    Directory of Open Access Journals (Sweden)

    Norman eWoller

    2014-07-01

    Full Text Available Oncolytic virotherapy has shown impressive results in preclinical studies and first promising therapeutic outcomes in clinical trials as well. Since viruses are known for a long time as excellent vaccination agents, oncolytic viruses are now designed as novel anticancer agents combining the aspect of lysis-dependent cytoreductive activity with concomitant induction of antitumoral immune responses. Antitumoral immune activation by oncolytic virus infection of tumor tissue comprises both, immediate effects of innate immunity and also adaptive responses for long lasting antitumoral activity which is regarded as the most prominent challenge in clinical oncology. To date, the complex effects of a viral tumor infection on the tumor microenvironment and the consequences for the tumor-infiltrating immune cell compartment are poorly understood. However, there is more and more evidence that a tumor infection by an oncolytic virus opens up a number of options for further immunomodulating interventions such as systemic chemotherapy, generic immunostimulating strategies, dendritic cell-based vaccines, and antigenic libraries to further support clinical efficacy of oncolytic virotherapy.

  10. Bat Flight and Zoonotic Viruses

    Centers for Disease Control (CDC) Podcasts

    2014-05-30

    Reginald Tucker reads an abridged version of the EID perspective Bat Flight and Zoonotic Viruses.  Created: 5/30/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 6/2/2014.

  11. Threat from Emerging Vectorborne Viruses

    Centers for Disease Control (CDC) Podcasts

    2016-06-09

    Reginald Tucker reads an abridged version of the commentary by CDC author Ronald Rosenberg, Threat from Emerging Vectorborne Viruses.  Created: 6/9/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 6/9/2016.

  12. Control of feline leukaemia virus.

    NARCIS (Netherlands)

    K. Weijer (Kees); F.G.C.M. Uytdehaag (Fons); A.D.M.E. Osterhaus (Ab)

    1989-01-01

    textabstractFeline leukaemia virus (FeLV) usually occurs in its natural species, the domestic cat. FeLV is also important to human individuals as a comparative model, as it may cause a variety of diseases, some malignant and some benign, such as immunosuppression, which bears a resemblance to AIDS (

  13. Enumerating viruses in coral mucus

    OpenAIRE

    Leruste, Amandine; Bouvier, Thierry; Bettarel, Yvan

    2012-01-01

    The distribution of viruses inhabiting the coral mucus remains undetermined, as there is no suitable standardized procedure for their separation from this organic matrix, principally owing to its viscosity and autofluorescence. Seven protocols were tested, and the most efficient separations were obtained from a chemical treatment requiring potassium citrate.

  14. Enumerating viruses in coral mucus.

    Science.gov (United States)

    Leruste, Amandine; Bouvier, Thierry; Bettarel, Yvan

    2012-09-01

    The distribution of viruses inhabiting the coral mucus remains undetermined, as there is no suitable standardized procedure for their separation from this organic matrix, principally owing to its viscosity and autofluorescence. Seven protocols were tested, and the most efficient separations were obtained from a chemical treatment requiring potassium citrate. PMID:22729548

  15. Molecular phylogeny of Duvenhage virus

    Directory of Open Access Journals (Sweden)

    Louis H. Nel

    2011-11-01

    Full Text Available The Duvenhage virus (DUVV constitutes one of the 11 species in the Lyssavirus genus and causes fatal rabies encephalitis. The virus is associated with insectivorous bat species and three human cases have been reported, all of which were linked to contact with bats. Few of these isolates have been studied and thus little is known about the phylogeny and epidemiology of this lyssavirus. Until 2007, when an isolate was made from the East African country of Kenya, all isolations of this virus had been from southern Africa. This discovery led to many questions regarding the spread and diversity of this lyssavirus. Phylogenetic analysis indicated that the DUVV isolates constitute two different lineages, in which the southern African isolates group together to form one lineage and the more recent isolate from Kenya constitutes a new, second lineage. We found that the new isolate has a genetic variation that has not yet been seen for DUVV. Not only is our lack of knowledge regarding the geographical distribution of this uniquely African virus emphasised, but we have also demonstrated the potential diversity within this genotype.

  16. Sandfly Fever Sicilian Virus, Algeria

    OpenAIRE

    Izri, Arezki; Temmam, Sarah; Moureau, Grégory; Hamrioui, Boussad; de Lamballerie, Xavier; Charrel, Rémi N.

    2008-01-01

    To determine whether sandfly fever Sicilian virus (SFSV) is present in Algeria, we tested sandflies for phlebovirus RNA. A sequence closely related to that of SFSV was detected in a Phlebotomus ariasi sandfly. Of 60 human serum samples, 3 contained immunoglobulin G against SFSV. These data suggest SFSV is present in Algeria.

  17. Mayaro Fever Virus, Brazilian Amazon

    OpenAIRE

    Azevedo, Raimunda S. S.; Silva, Eliana V. P.; Carvalho, Valéria L.; Rodrigues, Sueli G.; Neto, Joaquim P. Nunes; Monteiro, Hamilton A. de O.; Peixoto, Victor S.; Chiang, Jannifer O.; Nunes, Márcio R. T.; Vasconcelos, Pedro F.C.

    2009-01-01

    In February 2008, a Mayaro fever virus (MAYV) outbreak occurred in a settlement in Santa Barbara municipality, northern Brazil. Patients had rash, fever, and severe arthralgia lasting up to 7 days. Immunoglobulin M against MAYV was detected by ELISA in 36 persons; 3 MAYV isolates sequenced were characterized as genotype D.

  18. Mutants of alfalfa mosaic virus

    International Nuclear Information System (INIS)

    In this thesis the isolation and characterization of a number of mutants of alfalfa mosaic virus, a plant virus with a coat protein dependent genome, is described. Thermo-sensitive (ts) mutants were selected since, at least theoretically, ts mutations can be present in all virus coded functions. It was found that a high percentage of spontaneous mutants, isolated because of their aberrant symptoms, were ts. The majority of these isolates could grow at the non-permissive temperature in the presence of a single wild type (wt) component. To increase the mutation rate virus preparations were treated with several mutagens. After nitrous acid treatment or irradiation with ultraviolet light, an increase in the level of mutations was observed. UV irradiation was preferred since it did not require large amounts of purified viral components. During the preliminary characterization of potential ts mutants the author also obtained one structural and several symptom mutants which were analysed further (chapter 7, 8 and 9). The properties of the ts mutants are described in chapter 3-7. (Auth.)

  19. West Nile Virus Neuroinvasive Disease

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2009-07-01

    Full Text Available Epidemiological features of West Nile Virus (WNV disease among children (<18 years of age reported to the Centers for Disease Control and Prevention from 1999 through 2007 were analyzed and compared with those of adult WNV neuroinvasive disease (WNND, in a study at CDC&P, Fort Collins, CO.

  20. A Case of Ebola Virus

    Centers for Disease Control (CDC) Podcasts

    2012-10-01

    Dr. Adam MacNeil, an epidemiologist at CDC, discusses Ebola virus.  Created: 10/1/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID); National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 10/1/2012.

  1. Microcephaly and the Zika virus.

    Science.gov (United States)

    2016-09-12

    Cases of microcephaly brought about by the Zika virus have brought professional and personal challenges for nurses in Brazil. Paediatric nurses, such as Roberta Seabra (pictured), take over as part of the multidisciplinary team once the baby is born. In this article health writer Jacqui Thornton presents some personal stories. PMID:27615590

  2. Psoralen inactivation of influenza and herpes simplex viruses and of virus-infected cells

    International Nuclear Information System (INIS)

    Psoralen compounds covalently bind to nucleic acids when irradiated with long-wavelength ultraviolet light. This treatment can destroy the infectivity of deoxyribonucleic acid and ribonucleic acid viruses. Two psoralen compounds, 4'-hydroxymethyltrioxsalen and 4'-aminomethyltrioxsalen, were used with long-wavelength ultraviolet light to inactivate cell-free herpes simplex and influenza viruses and to render virus-infected cells noninfectious. This method of inactivation was compared with germicidal (short-wavelength) ultraviolet light irradiation. The antigenicity of the treated, virus-infected, antigen-bearing cells was examined by immunofluorescence and radioimmunoassay and by measuring the capacity of the herpes simplex virus-infected cells to stimulate virus-specific lymphocyte proliferation. The infectivity of the virus-infected cells could be totally eliminated without altering their viral antigenicity. The use of psoralen plus long-wavelength ultraviolet light is well suited to the preparation of noninfectious virus antigens and virus antigen-bearing cells for immunological assays

  3. Status of tobacco viruses in Serbia and molecular characterization of tomato spotted wilt virus isolates.

    Science.gov (United States)

    Stanković, I; Bulajić, A; Vučurović, A; Ristić, D; Milojević, K; Berenji, J; Krstić, B

    2011-01-01

    In a four-year survey to determine the presence and distribution of viruses in tobacco crops at 17 localities of the Vojvodina Province and Central Serbia, 380 samples were collected and analyzed by DAS-ELISA. Out of the seven viruses tested, tomato spotted wilt virus (TSWV), potato virus Y (PVY), tobacco mosaic virus (TMV), cucumber mosaic virus (CMV), and alfalfa mosaic virus (AMV) were detected in 37.9, 33.4, 28.7, 23.9, and 15.5% of the total tested samples, respectively. TSWV was the most frequently found virus at the localities of Central Serbia, while PVY and CMV were the most frequent viruses in the Vojvodina Province. Single infections were prevalent in years 2005-2007 and the most frequent were those of PVY. A triple combination of those viruses was most frequent mixed infection type in 2008. The presence of all five detected viruses was confirmed in selected ELISA-positive samples by RT-PCR and sequencing. The comparisons of obtained virus isolate sequences with those available in NCBI, confirmed the authenticity of serologically detected viruses. Phylogenetic analysis based on partial nucleocapsid gene sequences revealed a joint clustering of Serbian, Bulgarian and Montenegrin TSWV isolates into one geographic subpopulation, which was distinct from the other subpopulation of TSWV isolates from the rest of the European countries. The high incidence of viruses in Serbian tobacco crops highlights the importance of enhancing farmers knowledge towards better implementation of control strategies for preventing serious losses. PMID:22149499

  4. Clinical and biological differences between recurrent herpes simplex virus and varicella-zoster virus infections

    International Nuclear Information System (INIS)

    The major features that distinguish recurrent herpes simplex virus infections from zoster are illustrated in this article by two case histories. The clinical and epidemiologic features that characterize recurrent herpes simplex virus and varicella-zoster virus infections are reviewed. It is noted that herpesvirus infections are more common and severe in patients with cellular immune deficiency. Each virus evokes both humoral and cellular immune response in the course of primary infection. DNA hybridization studies with RNA probes labelled with sulfur-35 indicate that herpes simplex viruses persist within neurons, and that varicella-zoster virus is found in the satellite cells that encircle the neurons

  5. Contemporary North American influenza H7 viruses possess human receptor specificity: Implications for virus transmissibility

    DEFF Research Database (Denmark)

    Belser, Jessica A; Blixt, Ola; Chen, Li-Mei; Pappas, Claudia; Maines, Taronna R; Van Hoeven, Neal; Donis, Ruben; Busch, Julia; McBride, Ryan; Paulson, James C; Katz, Jacqueline M; Tumpey, Terrence M

    2008-01-01

    viruses from The Netherlands in 2003 maintained the classic avian-binding preference for alpha2-3-linked sialic acids (SA) and are not readily transmissible in ferrets, as observed previously for highly pathogenic H5N1 viruses. However, H7N3 viruses isolated from Canada in 2004 and H7N2 viruses from the...... in the upper respiratory tract of ferrets and was capable of transmission in this species by direct contact. These results indicate that H7 influenza viruses from the North American lineage have acquired sialic acid-binding properties that more closely resemble those of human influenza viruses and...

  6. 21 CFR 866.3305 - Herpes simplex virus serological assays.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Herpes simplex virus serological assays. 866.3305... simplex virus serological assays. (a) Identification. Herpes simplex virus serological assays are devices... herpes simplex virus in serum. Additionally, some of the assays consist of herpes simplex virus...

  7. Blueberry latent virus: An Amalgam of the Totiviridae and Partitiviridae

    Science.gov (United States)

    A new, symptomless virus was identified in blueberry. The dsRNA genome of the virus, provisionally named Blueberry latent virus (BBLV), codes for two putative proteins and lacks a movement protein, a property only shared with cryptic viruses. More than 35 isolates of the virus from different cultiv...

  8. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Wart Vaccine, Killed Virus. 113.206... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart Vaccine, Killed Virus. Wart Vaccine, Killed Virus, shall be...

  9. 9 CFR 113.311 - Bovine Virus Diarrhea Vaccine.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Bovine Virus Diarrhea Vaccine. 113.311... Virus Vaccines § 113.311 Bovine Virus Diarrhea Vaccine. Bovine Virus Diarrhea Vaccine shall be prepared... virus diarrhea susceptible calves shall be used as test animals (20 vaccinates and five controls)....

  10. [Epidemiological characteristics of Zika virus disease].

    Science.gov (United States)

    Li, Jiandong; Li, Dexin

    2016-03-01

    Zika virus disease is an emerging mosquito-borne acute infectious disease caused by Zika virus, so far there have been no available vaccine or specific treatment. Currently, the outbreaks of Zika virus disease mainly occurs in the Americas, but the regional distribution of the disease is in rapid expansion, 34 countries and territories have reported autochthonous transmission of the virus. The illness is usually mild with very rarely death, but increased reports of birth defects and neurologic disorders in the areas affected by Zika virus has caused extensive concern worldwide. In China, the competent vectors for Zika virus are widely distributed, imported viraemic cases may become a source of local transmission of the virus. However, Zika virus disease is preventable, the spread of virus could be stopped when the effective prevention measures are taken. This paper summarizes the retrieval results from Medline database and the information from the reports of the governments of countries affected or health organizations about the epidemiological characteristics of Zika virus disease. PMID:27005530

  11. Occurrence of viruses infecting pea in Iran.

    Science.gov (United States)

    Esfandiari, N; Kohi-Habibi, M; Mosahebi, Gh

    2006-01-01

    A survey was conducted to determine the incidence of Alfalfa mosaic virus (AMV), Bean yellow mosaic virus (BYMV), Broad bean wilt virus-1 (BBWV), Pea leafroll virus (PLRV), Pea enation mosaic virus (PEMV), Pea seed borne mosaic virus (PSbMV), Potato virus x(PVX), Tomato mosaic virus (ToMV), Tomato spotted wilt virus (TSWV) on pea (Pisum sativum) in Iran. A Total of 1276 random and 684 symptomatic pea samples were collected during the spring and summer of 2002-2004 in Tehran province of Iran, where pea is grown, and tested by enzyme-linked immunosorbent assay (ELISA) using specific polyclonal antibodies. Serological diagnoses were confirmed by electron microscopy and host range studies. Incidence of viruses in decreasing order was PVX (69%), ToMV (59%), PSbMV (36.6%), BBWV-1 (26.1%), BYMV (20.3%), AMV (17.77%), TSWV (12.6%), PEMV (10.9%), PLRV (6.78%). In this survey, natural occurrence of AMV, BBWV-1, PSbMV, TSWV, PVX and ToMV was reported for the first time on the pea in Iran. PMID:17390891

  12. Initial characterization of Vaccinia Virus B4 suggests a role in virus spread

    International Nuclear Information System (INIS)

    Currently, little is known about the ankyrin/F-box protein B4. Here, we report that B4R-null viruses exhibited reduced plaque size in tissue culture, and decreased ability to spread, as assessed by multiple-step growth analysis. Electron microscopy indicated that B4R-null viruses still formed mature and extracellular virions; however, there was a slight decrease of virions released into the media following deletion of B4R. Deletion of B4R did not affect the ability of the virus to rearrange actin; however, VACV811, a large vaccinia virus deletion mutant missing 55 open reading frames, had decreased ability to produce actin tails. Using ectromelia virus, a natural mouse pathogen, we demonstrated that virus devoid of EVM154, the B4R homolog, showed decreased spread to organs and was attenuated during infection. This initial characterization suggests that B4 may play a role in virus spread, and that other unidentified mediators of actin tail formation may exist in vaccinia virus. - Highlights: • B4R-null viruses show reduced plaque size, and decreased ability to spread. • B4R-null viruses formed mature and extracellular virions; and rearranged actin. • Virus devoid of EVM154, the B4R homolog, was attenuated during infection. • Initial characterization suggests that B4 may play a role in virus spread. • Unidentified mediators of actin tail formation may exist in vaccinia virus

  13. Human immunodeficiency virus, herpes virus infections, and pulmonary vascular disease

    OpenAIRE

    Flores, Sonia C.; Almodovar, Sharilyn

    2013-01-01

    The following state-of-the-art seminar was delivered as part of the Aspen Lung Conference on Pulmonary Hypertension and Vascular Diseases held in Aspen, Colorado in June 2012. This paper will summarize the lecture and present results from a nonhuman primate model of infection with Simian (Human) Immunodeficiency Virus - nef chimeric virions as well as the idea that polymorphisms in the HIV-1 nef gene may be driving the immune response that results in exuberant inflammation and aberrant endoth...

  14. Sequence and Structure Analysis of Distantly-Related Viruses Reveals Extensive Gene Transfer between Viruses and Hosts and among Viruses

    OpenAIRE

    Silvia Caprari; Saskia Metzler; Thomas Lengauer; Olga V Kalinina

    2015-01-01

    The origin and evolution of viruses is a subject of ongoing debate. In this study, we provide a full account of the evolutionary relationships between proteins of significant sequence and structural similarity found in viruses that belong to different classes according to the Baltimore classification. We show that such proteins can be found in viruses from all Baltimore classes. For protein families that include these proteins, we observe two patterns of the taxonomic spread. In the first pat...

  15. Type C virus activation in nontransformed mouse cells by uv-irradiated herpes simplex virus

    International Nuclear Information System (INIS)

    Infection of nontransformed mouse cells with uv-irradiated herpes simplex virus (uv-HSV) resulted in the activation of an endogenous xenotropic (x-tropic) type C virus. Synthesis of type C virus persisted for only a few days, with most of the virus remaining cell associated. The levels of type C virus activated by uv-HSV varied depending on the multiplicity of infection (m.o.i.) and the uv dose. At low uv doses, where cell killing occurred, little or no type C virus synthesis was observed. Maximum levels of type C virus synthesis were observed with the minimum uv dose which eliminated cell killing by HSV. Synthesis of type C virus, albeit at lower levels, was still observed at uv doses beyond those required to prevent cell killing

  16. Impact of anti-virus software on computer virus dynamical behavior

    Science.gov (United States)

    Sun, Mei; Li, Dandan; Han, Dun; Jia, Changsheng

    2014-11-01

    The impact of anti-virus software on the spreading of computer virus is investigated via developing a mathematical model in this paper. Considering the anti-virus software may not be effective, as it may be an outdated version, and then the computers may be infected with a reduced incidence rate. According to the method of next generation matrix, the basic reproduction number is derived. By introducing appropriate Lyapunov function and the Routh stability criterion, acquiring the stability conditions of the virus-free equilibrium and virus equilibrium. The effect of anti-virus software and disconnecting rate on the spreading of virus are also analyzed. When combined with the numerical results, a set of suggestions are put forward for eradicating virus effectively.

  17. Zika virus challenges for neuropsychiatry.

    Science.gov (United States)

    Simões E Silva, Ana Cristina; Moreira, Janaina Matos; Romanelli, Roberta Maia Castro; Teixeira, Antonio Lucio

    2016-01-01

    Before 2007, Zika virus (ZIKV) was generally considered as an arbovirus of low clinical relevance, causing a mild self-limiting febrile illness in tropical Africa and Southeast Asia. Currently, a large, ongoing outbreak of ZIKV that started in Brazil in 2015 is spreading across the Americas. Virus infection during pregnancy has been potentially linked to congenital malformations, including microcephaly. In addition to congenital malformations, a temporal association between ZIKV infection and an increase in cases of Guillain-Barré syndrome is currently being observed in several countries. The mechanisms underlying these neurological complications are still unknown. Emerging evidence, mainly from in vitro studies, suggests that ZIKV may have direct effects on neuronal cells. The aim of this study was to critically review the literature available regarding the neurobiology of ZIKV and its potential neuropsychiatric manifestations. PMID:27478378

  18. Simian virus 40 and cancer

    Directory of Open Access Journals (Sweden)

    Sandra Eliasz

    2011-12-01

    Full Text Available Since its discovery in 1960 as a contaminant of poliovaccines, Simian Virus 40 (SV40 has been the object of extensive studies to assess whether this oncogenic virus plays a role in human carcinogenesis. Over the last two decades, this question has met with broad scepticism. However, there is increasing evidence linking SV40 to specific types of human cancer, especially malignant mesothelioma. Recently, two laboratories using different experimental approaches independently confirmed that SV40 acts synergistically with environmental fibers to promote mesothelial cell transformation and mesothelioma. Most of the scepticism concerning SV40 and cancer was due to the lack of clear epidemiologic data. However, it is still not clear how SV40 circulates in the human population, making the identification of SV40-exposed versus non-exposed cohorts problematic. Consequently, the most helpful insights into SV40-mediated carcinogenesis have come from molecular pathology, cell and molecular biology, and from animal studies.

  19. Zika virus challenges for neuropsychiatry

    Science.gov (United States)

    Simões e Silva, Ana Cristina; Moreira, Janaina Matos; Romanelli, Roberta Maia Castro; Teixeira, Antonio Lucio

    2016-01-01

    Before 2007, Zika virus (ZIKV) was generally considered as an arbovirus of low clinical relevance, causing a mild self-limiting febrile illness in tropical Africa and Southeast Asia. Currently, a large, ongoing outbreak of ZIKV that started in Brazil in 2015 is spreading across the Americas. Virus infection during pregnancy has been potentially linked to congenital malformations, including microcephaly. In addition to congenital malformations, a temporal association between ZIKV infection and an increase in cases of Guillain–Barré syndrome is currently being observed in several countries. The mechanisms underlying these neurological complications are still unknown. Emerging evidence, mainly from in vitro studies, suggests that ZIKV may have direct effects on neuronal cells. The aim of this study was to critically review the literature available regarding the neurobiology of ZIKV and its potential neuropsychiatric manifestations. PMID:27478378

  20. Immune Response to Ebola Virus Infection

    Directory of Open Access Journals (Sweden)

    Alain Alonso Remedios

    2016-06-01

    Full Text Available Ebola virus belongs to the family Filoviridae and causes a highly lethal hemorrhagic fever. Affected patients show an impaired immune response as a result of the evasion mechanisms employed by the virus. Cathepsin is an enzyme present in the granules of phagocytes which cleaves viral surface glycoproteins, allowing virus entry into the host cell. In addition, this virus is resistant to the antiviral effects of type I interferon, promotes the synthesis of proinflammatory cytokines and induces apoptosis of monocytes and lymphocytes. It also induces an incomplete activation of dendritic cells, thus avoiding the presentation of viral antigens. Although specific antibodies are produced after the first week, their neutralizing capacity is doubtful. The virus evades the immune response and replicates uncontrollably in the host. This paper aims to summarize the main characteristics of the immune response to Ebola virus infection.