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Sample records for animal sars viruses

  1. Anti-SARS virus antibody responses against human SARS-associated coronavirus and animal SARS-associated coronavirus-like virus

    Institute of Scientific and Technical Information of China (English)

    王鸣; 徐慧芳; 莫自耀; 郑伯健; 高阳; 顾菁; 秦鹏哲; 张周斌; 邹晓忠; 梁彩云; 赵宇腾; 高凯

    2004-01-01

    @@ Severe acute respiratory syndrome (SARS) is an infectious disease first recognized in November 2002 in Guangdong province, China. It was spread to many countries all over the world within a few months.1,2 By April 2003, SARS-associated coronavirus (SARS-CoV) was found to be the etiological agent.

  2. Establishment of animal model for potency evaluation of inactivated SARS virus experimental vaccine

    Institute of Scientific and Technical Information of China (English)

    GUANMUDONG; QIAN; YANKONG; WENXUELIU; LIHINGYANG; JUNZHIWANG; YONGXINYU; YAOLONGSHU; ZHENGWANG; WEIDONGYIN; QINGYUZHU; HAIFAZHENG

    2005-01-01

    The purpose of this study was to test the effectiveness of source virus strain for the manufacture of the inactivated SARS virus vaccine, and establish an experimental method and preliminary standard for potency evaluation. Mice were divided into groups for being immunized with corresponding serially diluted experimental SARS virus inactivated vaccine. And the rabbits were immunized with undiluted vaccine. Challenge assay was conducted with a heterologous SARS virus. And the neutralization antibody was determined with plaque reduction neutralization test(PRNT), to which the neutralization antibody in the convalescent serum of SARS patients was compared. The experimental vaccine viral strains were proved to be suitable for manufacturing the vaccine. Mice immunized by vaccines of serial dilutions were able to elicit neutralizing antibody. The antibody titer from mice immunized with the undiluted vaccine could reach up to 1:495.2, while those of rabbits immunized with the undiluted vaccine could reach a GMT of 55.0-79.9. The capability of the antibody to neutralize the virus from Guangdong is more efficient than that from Beijing. The GMT of neutralizing antibody in SARS convalescents living in south and north China ranged from 50.12 to 54.95, and the titers of convalescents from north China were higher than those from south China. Mice and rabbits used as the model for evaluation of potency are of sensitivity, and the test is of reproducibility. The candidate challenge viral strains showed a relatively consistent effect on evaluating antibodies produced by various batches and different vaccine-source strains,hence they can be used to evaluate potency of the vaccine. The method for testing the vaccine potency and the evaluation standard was established preliminarily.

  3. Virus Infection and Titration of SARS-CoV in Mouse Lung

    OpenAIRE

    Fett, Craig; Zhao, Jincun; Perlman, Stanley

    2014-01-01

    Two critical steps when investigating an animal model of a virus infection are consistently successfully infecting animals and accurately determining viral titers in tissue throughout the course of infection. Here we discuss in detail how to infect mice with SARS-CoV and then quantify the titer of virus in the lung.

  4. New pathogenic mechanism of SARS virus

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ The outbreak of the severe acute respiratory syndrome (SARS) in 2002 caused alarm across the world. A coronavirus in humans, called SARS-CoV, has been identified as the causative agent for this killer disease.

  5. 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

  6. Bats Found to Carry SARS-like Virus

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ An international consortium headed by CAS researchers has identified that the Chinese horseshoe bat is healthy carriers of a virus that is very closely related to those causing SARS(severe acute respiratory syndrome). Their work was reported online on Sept. 29 by the Science magazine. The finding supports an independent study with similar results by Hong Kong scientists,which is reported by the Sept. 27issue of Proceedings of the National Academy of Sciences.

  7. Reverse genetics of SARS-related coronavirus using vaccinia virus-based recombination.

    Directory of Open Access Journals (Sweden)

    Sjoerd H E van den Worm

    Full Text Available Severe acute respiratory syndrome (SARS is a zoonotic disease caused by SARS-related coronavirus (SARS-CoV that emerged in 2002 to become a global health concern. Although the original outbreak was controlled by classical public health measures, there is a real risk that another SARS-CoV could re-emerge from its natural reservoir, either in its original form or as a more virulent or pathogenic strain; in which case, the virus would be difficult to control in the absence of any effective antiviral drugs or vaccines. Using the well-studied SARS-CoV isolate HKU-39849, we developed a vaccinia virus-based SARS-CoV reverse genetic system that is both robust and biosafe. The SARS-CoV genome was cloned in separate vaccinia virus vectors, (vSARS-CoV-5prime and vSARS-CoV-3prime as two cDNAs that were subsequently ligated to create a genome-length SARS-CoV cDNA template for in vitro transcription of SARS-CoV infectious RNA transcripts. Transfection of the RNA transcripts into permissive cells led to the recovery of infectious virus (recSARS-CoV. Characterization of the plaques produced by recSARS-CoV showed that they were similar in size to the parental SARS-CoV isolate HKU-39849 but smaller than the SARS-CoV isolate Frankfurt-1. Comparative analysis of replication kinetics showed that the kinetics of recSARS-CoV replication are similar to those of SARS-CoV Frankfurt-1, although the titers of virus released into the culture supernatant are approximately 10-fold less. The reverse genetic system was finally used to generate a recSARS-CoV reporter virus expressing Renilla luciferase in order to facilitate the analysis of SARS-CoV gene expression in human dendritic cells (hDCs. In parallel, a Renilla luciferase gene was also inserted into the genome of human coronavirus 229E (HCoV-229E. Using this approach, we demonstrate that, in contrast to HCoV-229E, SARS-CoV is not able to mediate efficient heterologous gene expression in hDCs.

  8. Hendra virus and Nipah virus animal vaccines.

    Science.gov (United States)

    Broder, Christopher C; Weir, Dawn L; Reid, Peter A

    2016-06-24

    Hendra virus (HeV) and Nipah virus (NiV) are zoonotic viruses that emerged in the mid to late 1990s causing disease outbreaks in livestock and people. HeV appeared in Queensland, Australia in 1994 causing a severe respiratory disease in horses along with a human case fatality. NiV emerged a few years later in Malaysia and Singapore in 1998-1999 causing a large outbreak of encephalitis with high mortality in people and also respiratory disease in pigs which served as amplifying hosts. The key pathological elements of HeV and NiV infection in several species of mammals, and also in people, are a severe systemic and often fatal neurologic and/or respiratory disease. In people, both HeV and NiV are also capable of causing relapsed encephalitis following recovery from an acute infection. The known reservoir hosts of HeV and NiV are several species of pteropid fruit bats. Spillovers of HeV into horses continue to occur in Australia and NiV has caused outbreaks in people in Bangladesh and India nearly annually since 2001, making HeV and NiV important transboundary biological threats. NiV in particular possesses several features that underscore its potential as a pandemic threat, including its ability to infect humans directly from natural reservoirs or indirectly from other susceptible animals, along with a capacity of limited human-to-human transmission. Several HeV and NiV animal challenge models have been developed which have facilitated an understanding of pathogenesis and allowed for the successful development of both active and passive immunization countermeasures. PMID:27154393

  9. Transmission of SARS and MERS coronaviruses and influenza virus in healthcare settings: the possible role of dry surface contamination.

    Science.gov (United States)

    Otter, J A; Donskey, C; Yezli, S; Douthwaite, S; Goldenberg, S D; Weber, D J

    2016-03-01

    Viruses with pandemic potential including H1N1, H5N1, and H5N7 influenza viruses, and severe acute respiratory syndrome (SARS)/Middle East respiratory syndrome (MERS) coronaviruses (CoV) have emerged in recent years. SARS-CoV, MERS-CoV, and influenza virus can survive on surfaces for extended periods, sometimes up to months. Factors influencing the survival of these viruses on surfaces include: strain variation, titre, surface type, suspending medium, mode of deposition, temperature and relative humidity, and the method used to determine the viability of the virus. Environmental sampling has identified contamination in field-settings with SARS-CoV and influenza virus, although the frequent use of molecular detection methods may not necessarily represent the presence of viable virus. The importance of indirect contact transmission (involving contamination of inanimate surfaces) is uncertain compared with other transmission routes, principally direct contact transmission (independent of surface contamination), droplet, and airborne routes. However, influenza virus and SARS-CoV may be shed into the environment and be transferred from environmental surfaces to hands of patients and healthcare providers. Emerging data suggest that MERS-CoV also shares these properties. Once contaminated from the environment, hands can then initiate self-inoculation of mucous membranes of the nose, eyes or mouth. Mathematical and animal models, and intervention studies suggest that contact transmission is the most important route in some scenarios. Infection prevention and control implications include the need for hand hygiene and personal protective equipment to minimize self-contamination and to protect against inoculation of mucosal surfaces and the respiratory tract, and enhanced surface cleaning and disinfection in healthcare settings. PMID:26597631

  10. Transmission of SARS and MERS coronaviruses and influenza virus in healthcare settings: the possible role of dry surface contamination.

    Science.gov (United States)

    Otter, J A; Donskey, C; Yezli, S; Douthwaite, S; Goldenberg, S D; Weber, D J

    2016-03-01

    Viruses with pandemic potential including H1N1, H5N1, and H5N7 influenza viruses, and severe acute respiratory syndrome (SARS)/Middle East respiratory syndrome (MERS) coronaviruses (CoV) have emerged in recent years. SARS-CoV, MERS-CoV, and influenza virus can survive on surfaces for extended periods, sometimes up to months. Factors influencing the survival of these viruses on surfaces include: strain variation, titre, surface type, suspending medium, mode of deposition, temperature and relative humidity, and the method used to determine the viability of the virus. Environmental sampling has identified contamination in field-settings with SARS-CoV and influenza virus, although the frequent use of molecular detection methods may not necessarily represent the presence of viable virus. The importance of indirect contact transmission (involving contamination of inanimate surfaces) is uncertain compared with other transmission routes, principally direct contact transmission (independent of surface contamination), droplet, and airborne routes. However, influenza virus and SARS-CoV may be shed into the environment and be transferred from environmental surfaces to hands of patients and healthcare providers. Emerging data suggest that MERS-CoV also shares these properties. Once contaminated from the environment, hands can then initiate self-inoculation of mucous membranes of the nose, eyes or mouth. Mathematical and animal models, and intervention studies suggest that contact transmission is the most important route in some scenarios. Infection prevention and control implications include the need for hand hygiene and personal protective equipment to minimize self-contamination and to protect against inoculation of mucosal surfaces and the respiratory tract, and enhanced surface cleaning and disinfection in healthcare settings.

  11. How change of public transportation usage reveals fear of the SARS virus in a city.

    Directory of Open Access Journals (Sweden)

    Kuo-Ying Wang

    Full Text Available The outbreaks of the severe acute respiratory syndrome (SARS epidemic in 2003 resulted in unprecedented impacts on people's daily life. One of the most significant impacts to people is the fear of contacting the SARS virus while engaging daily routine activity. Here we use data from daily underground ridership in Taipei City and daily reported new SARS cases in Taiwan to model the dynamics of the public fear of the SARS virus during the wax and wane of the SARS period. We found that for each reported new SARS case there is an immediate loss of about 1200 underground ridership (the fresh fear. These daily loss rates dissipate to the following days with an e-folding time of about 28 days, reflecting the public perception on the risk of contacting SARS virus when traveling with the underground system (the residual fear. About 50% of daily ridership was lost during the peak of the 2003 SARS period, compared with the loss of 80% daily ridership during the closure of the underground system after Typhoon Nari, the loss of 50-70% ridership due to the closure of the governmental offices and schools during typhoon periods, and the loss of 60% daily ridership during Chinese New Year holidays.

  12. The animal origin of SARS-CoV

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The first case of severe acute respiratory syndrome(SARS)in Guangdong province was reported on2Jan2003,whileretrospective survey has datedthe first index case on16Nov2002.In months that followed,pandemic of SARS widelyspread over the world until July2003,infecting8454people and claiming908deathsin39countries andregions global-ly.On16Dec2003,a32years old photographerlivinginsuburban Guangzhou presented withsymptoms of SARSinfec-tion.There were3other ensuing cases betweenthe end of2003and Jan2004.On23March200...

  13. Companion Animals as a Source of Viruses for Human Beings and Food Production Animals.

    Science.gov (United States)

    Reperant, L A; Brown, I H; Haenen, O L; de Jong, M D; Osterhaus, A D M E; Papa, A; Rimstad, E; Valarcher, J-F; Kuiken, T

    2016-07-01

    Companion animals comprise a wide variety of species, including dogs, cats, horses, ferrets, guinea pigs, reptiles, birds and ornamental fish, as well as food production animal species, such as domestic pigs, kept as companion animals. Despite their prominent place in human society, little is known about the role of companion animals as sources of viruses for people and food production animals. Therefore, we reviewed the literature for accounts of infections of companion animals by zoonotic viruses and viruses of food production animals, and prioritized these viruses in terms of human health and economic importance. In total, 138 virus species reportedly capable of infecting companion animals were of concern for human and food production animal health: 59 of these viruses were infectious for human beings, 135 were infectious for food production mammals and birds, and 22 were infectious for food production fishes. Viruses of highest concern for human health included hantaviruses, Tahyna virus, rabies virus, West Nile virus, tick-borne encephalitis virus, Crimean-Congo haemorrhagic fever virus, Aichi virus, European bat lyssavirus, hepatitis E virus, cowpox virus, G5 rotavirus, influenza A virus and lymphocytic choriomeningitis virus. Viruses of highest concern for food production mammals and birds included bluetongue virus, African swine fever virus, foot-and-mouth disease virus, lumpy skin disease virus, Rift Valley fever virus, porcine circovirus, classical swine fever virus, equine herpesvirus 9, peste des petits ruminants virus and equine infectious anaemia virus. Viruses of highest concern for food production fishes included cyprinid herpesvirus 3 (koi herpesvirus), viral haemorrhagic septicaemia virus and infectious pancreatic necrosis virus. Of particular concern as sources of zoonotic or food production animal viruses were domestic carnivores, rodents and food production animals kept as companion animals. The current list of viruses provides an objective

  14. A complete sequence and comparative analysis of a SARS-associated virus (Isolate BJ01)

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymousmutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to be involved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the M protein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides no evidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of other possible SARS-related pathogen(s).

  15. Relationship of SARS-CoV to other pathogenic RNA viruses explored by tetranucleotide usage profiling

    Directory of Open Access Journals (Sweden)

    Danchin Antoine

    2003-09-01

    Full Text Available Abstract Background The exact origin of the cause of the Severe Acute Respiratory Syndrome (SARS is still an open question. The genomic sequence relationship of SARS-CoV with 30 different single-stranded RNA (ssRNA viruses of various families was studied using two non-standard approaches. Both approaches began with the vectorial profiling of the tetra-nucleotide usage pattern V for each virus. In approach one, a distance measure of a vector V, based on correlation coefficient was devised to construct a relationship tree by the neighbor-joining algorithm. In approach two, a multivariate factor analysis was performed to derive the embedded tetra-nucleotide usage patterns. These patterns were subsequently used to classify the selected viruses. Results Both approaches yielded relationship outcomes that are consistent with the known virus classification. They also indicated that the genome of RNA viruses from the same family conform to a specific pattern of word usage. Based on the correlation of the overall tetra-nucleotide usage patterns, the Transmissible Gastroenteritis Virus (TGV and the Feline CoronaVirus (FCoV are closest to SARS-CoV. Surprisingly also, the RNA viruses that do not go through a DNA stage displayed a remarkable discrimination against the CpG and UpA di-nucleotide (z = -77.31, -52.48 respectively and selection for UpG and CpA (z = 65.79,49.99 respectively. Potential factors influencing these biases are discussed. Conclusion The study of genomic word usage is a powerful method to classify RNA viruses. The congruence of the relationship outcomes with the known classification indicates that there exist phylogenetic signals in the tetra-nucleotide usage patterns, that is most prominent in the replicase open reading frames.

  16. Transmission of Avian Influenza A Viruses Between Animals and People

    Science.gov (United States)

    ... Newsletters Transmission of Avian Influenza A Viruses Between Animals and People Language: English Español Recommend on ... Compartir Influenza A viruses have infected many different animals, including ducks, chickens, pigs, whales, horses, and seals. ...

  17. Animal Models of Dengue Virus Infection

    OpenAIRE

    Eva Harris; Simona Zompi

    2012-01-01

    The development of animal models of dengue virus (DENV) infection and disease has been challenging, as epidemic DENV does not naturally infect non-human species. Non-human primates (NHPs) can sustain viral replication in relevant cell types and develop a robust immune response, but they do not develop overt disease. In contrast, certain immunodeficient mouse models infected with mouse-adapted DENV strains show signs of severe disease similar to the ‘vascular-leak’ syndrome seen in severe deng...

  18. Emerging animal viruses: real threats or simple bystanders?

    OpenAIRE

    Eduardo Furtado Flores; Rudi Weiblen; Juliana Felipetto Cargnelutti; Fernando Viçosa Bauermann; Fernando Rosado Spilki; Enio Mori; Ana Cláudia Franco

    2013-01-01

    The list of animal viruses has been frequently added of new members raising permanent concerns to virologists and veterinarians. The pathogenic potential and association with disease have been clearly demonstrated for some, but not for all of these emerging viruses. This review describes recent discoveries of animal viruses and their potential relevance for veterinary practice. Dogs were considered refractory to influenza viruses until 2004, when an influenza A virus subtype H3N8 was transmit...

  19. Animal Models of Varicella Zoster Virus Infection

    Directory of Open Access Journals (Sweden)

    Ilhem Messaoudi

    2013-05-01

    Full Text Available Primary infection with varicella zoster virus (VZV results in varicella (chickenpox followed by the establishment of latency in sensory ganglia. Declining T cell immunity due to aging or immune suppressive treatments can lead to VZV reactivation and the development of herpes zoster (HZ, shingles. HZ is often associated with significant morbidity and occasionally mortality in elderly and immune compromised patients. There are currently two FDA-approved vaccines for the prevention of VZV: Varivax® (for varicella and Zostavax® (for HZ. Both vaccines contain the live-attenuated Oka strain of VZV. Although highly immunogenic, a two-dose regimen is required to achieve a 99% seroconversion rate. Zostavax vaccination reduces the incidence of HZ by 51% within a 3-year period, but a significant reduction in vaccine-induced immunity is observed within the first year after vaccination. Developing more efficacious vaccines and therapeutics requires a better understanding of the host response to VZV. These studies have been hampered by the scarcity of animal models that recapitulate all aspects of VZV infections in humans. In this review, we describe different animal models of VZV infection as well as an alternative animal model that leverages the infection of Old World macaques with the highly related simian varicella virus (SVV and discuss their contributions to our understanding of pathogenesis and immunity during VZV infection.

  20. Spike protein homology between the SARS-associated virus and murine hepatitis virus implies existence of a putative receptor-binding region

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Coronavirus has been determined to be the cause of the recent outbreak of severe acute respiratory syndrome (SARS). Human coronavirus 229E had been studied well and its receptor-binding domain was restricted to aa417-547 of S protein. However, this region has no homology with the newly separated SARS-associated virus (Hong Kong isolate CUHK-W1). Then we analyzed the phylogenesis of S1 subunit of the coronavirus spike protein (SARS-associated virus, Hong Kong isolate CUHK-W1). Interestingly, the highest homology between murine hepatitis virus (MHV) and SARS-associated coronavirus was found. And the important sites (aa62-65 and aa214-216) on the spike protein of MHV with receptor-binding capacity were highly conservative in comparison with the newly separated SARS-asso- ciated virus (the corresponding sites are aa51-54 and aa195-197). These results from bioinformatics analysis might help us to study the receptor-binding sites of SARS-associ- ated virus and the mechanism of the virus entry into the target cell, and design antiviral drugs and potent vaccines.

  1. Distinct patterns of IFITM-mediated restriction of filoviruses, SARS coronavirus, and influenza A virus.

    Directory of Open Access Journals (Sweden)

    I-Chueh Huang

    Full Text Available Interferon-inducible transmembrane proteins 1, 2, and 3 (IFITM1, 2, and 3 are recently identified viral restriction factors that inhibit infection mediated by the influenza A virus (IAV hemagglutinin (HA protein. Here we show that IFITM proteins restricted infection mediated by the entry glycoproteins (GP(1,2 of Marburg and Ebola filoviruses (MARV, EBOV. Consistent with these observations, interferon-β specifically restricted filovirus and IAV entry processes. IFITM proteins also inhibited replication of infectious MARV and EBOV. We observed distinct patterns of IFITM-mediated restriction: compared with IAV, the entry processes of MARV and EBOV were less restricted by IFITM3, but more restricted by IFITM1. Moreover, murine Ifitm5 and 6 did not restrict IAV, but efficiently inhibited filovirus entry. We further demonstrate that replication of infectious SARS coronavirus (SARS-CoV and entry mediated by the SARS-CoV spike (S protein are restricted by IFITM proteins. The profile of IFITM-mediated restriction of SARS-CoV was more similar to that of filoviruses than to IAV. Trypsin treatment of receptor-associated SARS-CoV pseudovirions, which bypasses their dependence on lysosomal cathepsin L, also bypassed IFITM-mediated restriction. However, IFITM proteins did not reduce cellular cathepsin activity or limit access of virions to acidic intracellular compartments. Our data indicate that IFITM-mediated restriction is localized to a late stage in the endocytic pathway. They further show that IFITM proteins differentially restrict the entry of a broad range of enveloped viruses, and modulate cellular tropism independently of viral receptor expression.

  2. Inhibitors for the hepatitis C virus RNA polymerase explored by SAR with advanced machine learning methods.

    Science.gov (United States)

    Weidlich, Iwona E; Filippov, Igor V; Brown, Jodian; Kaushik-Basu, Neerja; Krishnan, Ramalingam; Nicklaus, Marc C; Thorpe, Ian F

    2013-06-01

    Hepatitis C virus (HCV) is a global health challenge, affecting approximately 200 million people worldwide. In this study we developed SAR models with advanced machine learning classifiers Random Forest and k Nearest Neighbor Simulated Annealing for 679 small molecules with measured inhibition activity for NS5B genotype 1b. The activity was expressed as a binary value (active/inactive), where actives were considered molecules with IC50 ≤0.95 μM. We applied our SAR models to various drug-like databases and identified novel chemical scaffolds for NS5B inhibitors. Subsequent in vitro antiviral assays suggested a new activity for an existing prodrug, Candesartan cilexetil, which is currently used to treat hypertension and heart failure but has not been previously tested for anti-HCV activity. We also identified NS5B inhibitors with two novel non-nucleoside chemical motifs. PMID:23608107

  3. The structure of a rigorously conserved RNA element within the SARS virus genome.

    Directory of Open Access Journals (Sweden)

    Michael P Robertson

    2005-01-01

    Full Text Available We have solved the three-dimensional crystal structure of the stem-loop II motif (s2m RNA element of the SARS virus genome to 2.7-A resolution. SARS and related coronaviruses and astroviruses all possess a motif at the 3' end of their RNA genomes, called the s2m, whose pathogenic importance is inferred from its rigorous sequence conservation in an otherwise rapidly mutable RNA genome. We find that this extreme conservation is clearly explained by the requirement to form a highly structured RNA whose unique tertiary structure includes a sharp 90 degrees kink of the helix axis and several novel longer-range tertiary interactions. The tertiary base interactions create a tunnel that runs perpendicular to the main helical axis whose interior is negatively charged and binds two magnesium ions. These unusual features likely form interaction surfaces with conserved host cell components or other reactive sites required for virus function. Based on its conservation in viral pathogen genomes and its absence in the human genome, we suggest that these unusual structural features in the s2m RNA element are attractive targets for the design of anti-viral therapeutic agents. Structural genomics has sought to deduce protein function based on three-dimensional homology. Here we have extended this approach to RNA by proposing potential functions for a rigorously conserved set of RNA tertiary structural interactions that occur within the SARS RNA genome itself. Based on tertiary structural comparisons, we propose the s2m RNA binds one or more proteins possessing an oligomer-binding-like fold, and we suggest a possible mechanism for SARS viral RNA hijacking of host protein synthesis, both based upon observed s2m RNA macromolecular mimicry of a relevant ribosomal RNA fold.

  4. Coronavirus 3CLpro proteinase cleavage sites: Possible relevance to SARS virus pathology

    Directory of Open Access Journals (Sweden)

    Blom Nikolaj

    2004-06-01

    Full Text Available Abstract Background Despite the passing of more than a year since the first outbreak of Severe Acute Respiratory Syndrome (SARS, efficient counter-measures are still few and many believe that reappearance of SARS, or a similar disease caused by a coronavirus, is not unlikely. For other virus families like the picornaviruses it is known that pathology is related to proteolytic cleavage of host proteins by viral proteinases. Furthermore, several studies indicate that virus proliferation can be arrested using specific proteinase inhibitors supporting the belief that proteinases are indeed important during infection. Prompted by this, we set out to analyse and predict cleavage by the coronavirus main proteinase using computational methods. Results We retrieved sequence data on seven fully sequenced coronaviruses and identified the main 3CL proteinase cleavage sites in polyproteins using alignments. A neural network was trained to recognise the cleavage sites in the genomes obtaining a sensitivity of 87.0% and a specificity of 99.0%. Several proteins known to be cleaved by other viruses were submitted to prediction as well as proteins suspected relevant in coronavirus pathology. Cleavage sites were predicted in proteins such as the cystic fibrosis transmembrane conductance regulator (CFTR, transcription factors CREB-RP and OCT-1, and components of the ubiquitin pathway. Conclusions Our prediction method NetCorona predicts coronavirus cleavage sites with high specificity and several potential cleavage candidates were identified which might be important to elucidate coronavirus pathology. Furthermore, the method might assist in design of proteinase inhibitors for treatment of SARS and possible future diseases caused by coronaviruses. It is made available for public use at our website: http://www.cbs.dtu.dk/services/NetCorona/.

  5. Viral hemorrhagic fevers of animals caused by DNA viruses

    Science.gov (United States)

    Here we outline serious diseases of food and fiber animals that cause damaging economic effect on products all over the world. The only vector-borne DNA virus is included here, such as African swine fever virus, and the herpes viruses discussed have a complex epidemiology characterized by outbreak...

  6. Infection of SARS-CoV on juvenile and adult Brandt's vole Microtus brandtii

    Institute of Scientific and Technical Information of China (English)

    GAO Hong; PENG Jingpian; DENG Wei; SHI Dazhao; BAO Linlin; WANG Dehua; ZHANG Binglin; QIN Chuan; ZHANG Zhibin

    2005-01-01

    We studied the infectious effect of SARS-CoV virus on juvenile and adult Brandt's Vole (Microtus brandtii) by nasal cavity spraying method (CCID50 is 105.7). SARS virus caused serious deaths in adults. The death adults demonstrated hemorrhage from mouth, nasal cavity and intestine, hemorrhageious interstitial pneumonia and gore in liver, spleen and kidney. The survival adults demonstrated local hemorrhagic spot in lung and emphysema, but the other organs showed no pathological abnormality. SARS virus caused no deaths in juveniles, but locomotion of infected juveniles became slower. In the early stage, there was local pneumonia in lung and SARS viruses were isolated from the pathological tissue. Only one control juvenile lived and the infected juvenile showed local pneumonia in lung. The results demonstrated that SARS-CoV infected Brandt's vole seriously and adults were more susceptive to SARS-CoV than juveniles. The Brandt's vole may be a potential animal model for SARS research.

  7. Building on a solid foundation: SAR and QSAR as a fundamental strategy to reduce animal testing.

    Science.gov (United States)

    Sullivan, K M; Manuppello, J R; Willett, C E

    2014-01-01

    The development of more efficient, ethical, and effective means of assessing the effects of chemicals on human health and the environment was a lifetime goal of Gilman Veith. His work has provided the foundation for the use of chemical structure for informing toxicological assessment by regulatory agencies the world over. Veith's scientific work influenced the early development of the SAR models in use today at the US Environmental Protection Agency. He was the driving force behind the Organisation for Economic Co-operation and Development QSAR Toolbox. Veith was one of a few early pioneers whose vision led to the linkage of chemical structure and biological activity as a means of predicting adverse apical outcomes (known as a mode of action, or an adverse outcome pathway approach), and he understood at an early stage the power that could be harnessed when combining computational and mechanistic biological approaches as a means of avoiding animal testing. Through the International QSAR Foundation he organized like-minded experts to develop non-animal methods and frameworks for the assessment of chemical hazard and risk for the benefit of public and environmental health. Avoiding animal testing was Gil's passion, and his work helped to initiate the paradigm shift in toxicology that is now rendering this feasible. PMID:24773450

  8. Building on a solid foundation: SAR and QSAR as a fundamental strategy to reduce animal testing.

    Science.gov (United States)

    Sullivan, K M; Manuppello, J R; Willett, C E

    2014-01-01

    The development of more efficient, ethical, and effective means of assessing the effects of chemicals on human health and the environment was a lifetime goal of Gilman Veith. His work has provided the foundation for the use of chemical structure for informing toxicological assessment by regulatory agencies the world over. Veith's scientific work influenced the early development of the SAR models in use today at the US Environmental Protection Agency. He was the driving force behind the Organisation for Economic Co-operation and Development QSAR Toolbox. Veith was one of a few early pioneers whose vision led to the linkage of chemical structure and biological activity as a means of predicting adverse apical outcomes (known as a mode of action, or an adverse outcome pathway approach), and he understood at an early stage the power that could be harnessed when combining computational and mechanistic biological approaches as a means of avoiding animal testing. Through the International QSAR Foundation he organized like-minded experts to develop non-animal methods and frameworks for the assessment of chemical hazard and risk for the benefit of public and environmental health. Avoiding animal testing was Gil's passion, and his work helped to initiate the paradigm shift in toxicology that is now rendering this feasible.

  9. Animal Models of Dengue Virus Infection

    Directory of Open Access Journals (Sweden)

    Eva Harris

    2012-01-01

    Full Text Available The development of animal models of dengue virus (DENV infection and disease has been challenging, as epidemic DENV does not naturally infect non-human species. Non-human primates (NHPs can sustain viral replication in relevant cell types and develop a robust immune response, but they do not develop overt disease. In contrast, certain immunodeficient mouse models infected with mouse-adapted DENV strains show signs of severe disease similar to the ‘vascular-leak’ syndrome seen in severe dengue in humans. Humanized mouse models can sustain DENV replication and show some signs of disease, but further development is needed to validate the immune response. Classically, immunocompetent mice infected with DENV do not manifest disease or else develop paralysis when inoculated intracranially; however, a new model using high doses of DENV has recently been shown to develop hemorrhagic signs after infection. Overall, each model has its advantages and disadvantages and is differentially suited for studies of dengue pathogenesis and immunopathogenesis and/or pre-clinical testing of antiviral drugs and vaccines.

  10. Challenges presented by MERS corona virus, and SARS corona virus to global health

    OpenAIRE

    Ali Al-Hazmi

    2016-01-01

    Numerous viral infections have arisen and affected global healthcare facilities. Millions of people are at severe risk of acquiring several evolving viral infections through several factors. In the present article we have described about risk factors, chance of infection, and prevention methods of Middle East Respiratory Syndrome Coronavirus (MERS-CoV) and severe acute respiratory syndrome (SARS-CoV), human coronaviruses (CoVs) frequently cause a normal cold which is mild and self-restricting...

  11. A network integration approach to predict conserved regulators related to pathogenicity of influenza and SARS-CoV respiratory viruses.

    Directory of Open Access Journals (Sweden)

    Hugh D Mitchell

    Full Text Available Respiratory infections stemming from influenza viruses and the Severe Acute Respiratory Syndrome corona virus (SARS-CoV represent a serious public health threat as emerging pandemics. Despite efforts to identify the critical interactions of these viruses with host machinery, the key regulatory events that lead to disease pathology remain poorly targeted with therapeutics. Here we implement an integrated network interrogation approach, in which proteome and transcriptome datasets from infection of both viruses in human lung epithelial cells are utilized to predict regulatory genes involved in the host response. We take advantage of a novel "crowd-based" approach to identify and combine ranking metrics that isolate genes/proteins likely related to the pathogenicity of SARS-CoV and influenza virus. Subsequently, a multivariate regression model is used to compare predicted lung epithelial regulatory influences with data derived from other respiratory virus infection models. We predicted a small set of regulatory factors with conserved behavior for consideration as important components of viral pathogenesis that might also serve as therapeutic targets for intervention. Our results demonstrate the utility of integrating diverse 'omic datasets to predict and prioritize regulatory features conserved across multiple pathogen infection models.

  12. A Network Integration Approach to Predict Conserved Regulators Related to Pathogenicity of Influenza and SARS-CoV Respiratory Viruses

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Hugh D.; Eisfeld, Amie J.; Sims, Amy; McDermott, Jason E.; Matzke, Melissa M.; Webb-Robertson, Bobbie-Jo M.; Tilton, Susan C.; Tchitchek, Nicholas; Josset, Laurence; Li, Chengjun; Ellis, Amy L.; Chang, Jean H.; Heegel, Robert A.; Luna, Maria L.; Schepmoes, Athena A.; Shukla, Anil K.; Metz, Thomas O.; Neumann, Gabriele; Benecke, Arndt; Smith, Richard D.; Baric, Ralph; Kawaoka, Yoshihiro; Katze, Michael G.; Waters, Katrina M.

    2013-07-25

    Respiratory infections stemming from influenza viruses and the Severe Acute Respiratory Syndrome corona virus (SARS-CoV) represent a serious public health threat as emerging pandemics. Despite efforts to identify the critical interactions of these viruses with host machinery, the key regulatory events that lead to disease pathology remain poorly targeted with therapeutics. Here we implement an integrated network interrogation approach, in which proteome and transcriptome datasets from infection of both viruses in human lung epithelial cells are utilized to predict regulatory genes involved in the host response. We take advantage of a novel “crowd-based” approach to identify and combine ranking metrics that isolate genes/proteins likely related to the pathogenicity of SARS-CoV and influenza virus. Subsequently, a multivariate regression model is used to compare predicted lung epithelial regulatory influences with data derived from other respiratory virus infection models. We predicted a small set of regulatory factors with conserved behavior for consideration as important components of viral pathogenesis that might also serve as therapeutic targets for intervention. Our results demonstrate the utility of integrating diverse ‘omic datasets to predict and prioritize regulatory features conserved across multiple pathogen infection models.

  13. Naturally Occurring Animal Models of Human Hepatitis E Virus Infection

    OpenAIRE

    Yugo, Danielle M.; Cossaboom, Caitlin M.; Meng, Xiang-Jin

    2014-01-01

    Hepatitis E virus (HEV) is a single-stranded, positive-sense RNA virus in the family Hepeviridae. Hepatitis E caused by HEV is a clinically important global disease. There are currently four well-characterized genotypes of HEV in mammalian species, although numerous novel strains of HEV likely belonging to either new genotypes or species have recently been identified from several other animal species. HEV genotypes 1 and 2 are limited to infection in humans, whereas genotypes 3 and 4 infect a...

  14. Zoonotic Hepatitis E Virus: Classification, Animal Reservoirs and Transmission Routes

    Science.gov (United States)

    Doceul, Virginie; Bagdassarian, Eugénie; Demange, Antonin; Pavio, Nicole

    2016-01-01

    During the past ten years, several new hepatitis E viruses (HEVs) have been identified in various animal species. In parallel, the number of reports of autochthonous hepatitis E in Western countries has increased as well, raising the question of what role these possible animal reservoirs play in human infections. The aim of this review is to present the recent discoveries of animal HEVs and their classification within the Hepeviridae family, their zoonotic and species barrier crossing potential, and possible use as models to study hepatitis E pathogenesis. Lastly, this review describes the transmission pathways identified from animal sources. PMID:27706110

  15. Pesti Des Petits ruminants virus infection in animals

    Directory of Open Access Journals (Sweden)

    Chauhan H.C.

    2009-08-01

    Full Text Available For centuries morbillivirus infections have had a huge impact on both human beings and animals. Morbilliviruses are highly contagious pathogens that cause some of the most devastating viral diseases of humans and animals world wide. They include measles virus (MV, canine distemper virus (CDV, rinderpest virus (RPV and peste des petits ruminants (PPRV virus. Furthermore, new emerging infectious diseases of morbilliviruses with significant ecological consequences of marine mammals have been discovered in the past decades. Phocid distemper virus (PDV in seals and the cetacean morbillivirus (CMV have been found in dolphins, whales and porpoises. Peste des petits ruminants (PPR is a highly contagious ,infectious , an acute or sub acute viral disease of domestic and wild small ruminants characterized by fever, oculonasal discharges, stomatitis, conjunctivitis, gastroenteritis and pneumonia. Goats are more severely affected than sheep. It is also known as pseudorinderpest of small ruminants, pest of small ruminants, pest of sheep and goats, kata, stomatitis- pneumoentritis syndrome, contagious pustular stomatitis and pneumoentritis complex. It is one of the major notifiable diseases of the World Organization for Animal Health (OIE. [Vet. World 2009; 2(4.000: 150-155

  16. Emerging animal viruses: real threats or simple bystanders?

    Directory of Open Access Journals (Sweden)

    Eduardo Furtado Flores

    2013-10-01

    Full Text Available The list of animal viruses has been frequently added of new members raising permanent concerns to virologists and veterinarians. The pathogenic potential and association with disease have been clearly demonstrated for some, but not for all of these emerging viruses. This review describes recent discoveries of animal viruses and their potential relevance for veterinary practice. Dogs were considered refractory to influenza viruses until 2004, when an influenza A virus subtype H3N8 was transmitted from horses and produced severe respiratory disease in racing greyhounds in Florida/USA. The novel virus, named canine influenza virus (CIV, is considered now a separate virus lineage and has spread among urban canine population in the USA. A new pestivirus (Flaviviridae, tentatively called HoBi-like pestivirus, was identified in 2004 in commercial fetal bovine serum from Brazil. Hobi-like viruses are genetically and antigenically related to bovine viral diarrhea virus (BVDV and induce similar clinical manifestations. These novel viruses seem to be widespread in Brazilian herds and have also been detected in Southeast Asia and Europe. In 2011, a novel mosquito-borne orthobunyavirus, named Schmallenberg virus (SBV, was associated with fever, drop in milk production, abortion and newborn malformation in cattle and sheep in Germany. Subsequently, the virus disseminated over several European countries and currently represents a real treat for animal health. The origin of SBV is still a matter of debate but it may be a reassortant from previous known bunyaviruses Shamonda and Satuperi. Hepatitis E virus (HEV, family Hepeviridae is a long known agent of human acute hepatitis and in 1997 was first identified in pigs. Current data indicates that swine HEV is spread worldwide, mainly associated with subclinical infection. Two of the four HEV genotypes are zoonotic and may be transmitted between swine and human by contaminated water and undercooked pork meat. The

  17. Animal models of human respiratory syncytial virus disease

    NARCIS (Netherlands)

    R.A. Bem; J.B. Domachowske; H.F. Rosenberg

    2011-01-01

    Infection with the human pneumovirus pathogen, respiratory syncytial virus (hRSV), causes a wide spectrum of respiratory disease, notably among infants and the elderly. Laboratory animal studies permit detailed experimental modeling of hRSV disease and are therefore indispensable in the search for n

  18. SARS Vaccine: Progress and Challenge

    Institute of Scientific and Technical Information of China (English)

    Yan Zhi; James M. Wilson; Hao Shen

    2005-01-01

    Severe acute respiratory syndrome (SARS) emerged in 2002 as a severe and highly contagious infectious disease that rapidly spread to a number of different countries. The collaborative efforts of the global scientific community have provided, within a short period of time, substantial insights into the molecular biology and immunology of SARS-CoV. Although the outbreak has been contained, there is continuous concern that the virus may resurface into the human population through seasonal changes, animal reservoirs or laboratory accidents. The severe morbidity and mortality associated with SARS make it imperative that an effective vaccine be developed to prevent reemergence and epidemics in the future. Cellular & Molecular Immunology. 2005;2(2):101-105.

  19. SARS Vaccine: Progress and Challenge

    Institute of Scientific and Technical Information of China (English)

    YanZhi; JamesM.Wilson; HaoShen

    2005-01-01

    Severe acute respiratory syndrome (SARS) emerged in 2002 as a severe and highly contagious infectious disease that rapidly spread to a number of different countries. The collaborative efforts of the global scientific community have provided, within a short period of time, substantial insights into the molecular biology and immunology of SARS-CoV. Although the outbreak has been contained, there is continuous concern that the virus may resurface into the human population through seasonal changes, animal reservoirs or laboratory accidents. The severe morbidity and mortality associated with SARS make it imperative that an effective vaccine be developed to prevent reemergence and epidemics in the future. Cellular & Molecular Immunology. 2005;2(2):101-105.

  20. Understanding SARS with Wolfram Approach

    Institute of Scientific and Technical Information of China (English)

    Da-WeiLI; Yu-XiPAN; YunDUAN; Zhen-DeHUNG; Ming-QingXU; LinHE

    2004-01-01

    Stepping acquired immunodeficiency syndrome (AIDS), severe acute respiratory syndrome (SARS) as another type of disease has been threatening mankind since late last year. Many scientists worldwide are making great efforts to study the etiology of this disease with different approaches. 13 species of SARS virus have been sequenced. However, most people still largely rely on the traditional methods with some disadvantages. In this work, we used Wolfram approach to study the relationship among SARS viruses and between SARS viruses and other types of viruses, the effect of variations on the whole genome and the advantages in the analysis of SARS based on this novel approach. As a result, the similarities between SARS viruses and other coronaviruses are not really higher than those between SARS viruses and non-coronaviruses.

  1. Animal Models for Influenza Virus Pathogenesis and Transmission

    Directory of Open Access Journals (Sweden)

    Anice C. Lowen

    2010-07-01

    Full Text Available Influenza virus infection of humans results in a respiratory disease that ranges in severity from sub-clinical infection to primary viral pneumonia that can result in death. The clinical effects of infection vary with the exposure history, age and immune status of the host, and also the virulence of the influenza strain. In humans, the virus is transmitted through either aerosol or contact-based transfer of infectious respiratory secretions. As is evidenced by most zoonotic influenza virus infections, not all strains that can infect humans are able to transmit from person-to-person. Animal models of influenza are essential to research efforts aimed at understanding the viral and host factors that contribute to the disease and transmission outcomes of influenza virus infection in humans. These models furthermore allow the pre-clinical testing of antiviral drugs and vaccines aimed at reducing morbidity and mortality in the population through amelioration of the virulence or transmissibility of influenza viruses. Mice, ferrets, guinea pigs, cotton rats, hamsters and macaques have all been used to study influenza viruses and therapeutics targeting them. Each model presents unique advantages and disadvantages, which will be discussed herein.

  2. Memory T cell responses targeting the SARS coronavirus persist up to 11 years post-infection.

    Science.gov (United States)

    Ng, Oi-Wing; Chia, Adeline; Tan, Anthony T; Jadi, Ramesh S; Leong, Hoe Nam; Bertoletti, Antonio; Tan, Yee-Joo

    2016-04-12

    Severe acute respiratory syndrome (SARS) is a highly contagious infectious disease which first emerged in late 2002, caused by a then novel human coronavirus, SARS coronavirus (SARS-CoV). The virus is believed to have originated from bats and transmitted to human through intermediate animals such as civet cats. The re-emergence of SARS-CoV remains a valid concern due to the continual persistence of zoonotic SARS-CoVs and SARS-like CoVs (SL-CoVs) in bat reservoirs. In this study, the screening for the presence of SARS-specific T cells in a cohort of three SARS-recovered individuals at 9 and 11 years post-infection was carried out, and all memory T cell responses detected target the SARS-CoV structural proteins. Two CD8(+) T cell responses targeting the SARS-CoV membrane (M) and nucleocapsid (N) proteins were characterized by determining their HLA restriction and minimal T cell epitope regions. Furthermore, these responses were found to persist up to 11 years post-infection. An absence of cross-reactivity of these CD8(+) T cell responses against the newly-emerged Middle East respiratory syndrome coronavirus (MERS-CoV) was also demonstrated. The knowledge of the persistence of SARS-specific celullar immunity targeting the viral structural proteins in SARS-recovered individuals is important in the design and development of SARS vaccines, which are currently unavailable. PMID:26954467

  3. Identifying SARS-CoV membrane protein amino acid residues linked to virus-like particle assembly.

    Directory of Open Access Journals (Sweden)

    Ying-Tzu Tseng

    Full Text Available Severe acute respiratory syndrome coronavirus (SARS-CoV membrane (M proteins are capable of self-assembly and release in the form of membrane-enveloped vesicles, and of forming virus-like particles (VLPs when coexpressed with SARS-CoV nucleocapsid (N protein. According to previous deletion analyses, M self-assembly involves multiple M sequence regions. To identify important M amino acid residues for VLP assembly, we coexpressed N with multiple M mutants containing substitution mutations at the amino-terminal ectodomain, carboxyl-terminal endodomain, or transmembrane segments. Our results indicate that a dileucine motif in the endodomain tail (218LL219 is required for efficient N packaging into VLPs. Results from cross-linking VLP analyses suggest that the cysteine residues 63, 85 and 158 are not in close proximity to the M dimer interface. We noted a significant reduction in M secretion due to serine replacement for C158, but not for C63 or C85. Further analysis suggests that C158 is involved in M-N interaction. In addition to mutations of the highly conserved 107-SWWSFNPE-114 motif, substitutions at codons W19, W57, P58, W91, Y94 or F95 all resulted in significantly reduced VLP yields, largely due to defective M secretion. VLP production was not significantly affected by a tryptophan replacement of Y94 or F95 or a phenylalanine replacement of W19, W57 or W91. Combined, these results indicate the involvement of specific M amino acids during SARS-CoV virus assembly, and suggest that aromatic residue retention at specific positions is critical for M function in terms of directing virus assembly.

  4. Animal models for Ebola and Marburg virus infections

    Directory of Open Access Journals (Sweden)

    Eri eNakayama

    2013-09-01

    Full Text Available Ebola and Marburg hemorrhagic fevers (EHF and MHF are caused by the Filoviridae family, Ebolavirus and Marburgvirus (ebolavirus and marburgvirus, respectively. These severe diseases have high mortality rates in humans. Although EHF and MHF are endemic to sub-Saharan Africa. A novel filovirus, Lloviu virus, which is genetically distinct from ebolavirus and marburgvirus, was recently discovered in Spain where filoviral hemorrhagic fever had never been reported. The virulence of this virus has not been determined. Ebolavirus and marburgvirus are classified as biosafety level-4 (BSL-4 pathogens and Category A agents, for which the US government requires preparedness in case of bioterrorism. Therefore, preventive measures against these viral hemorrhagic fevers should be prepared, not only in disease-endemic regions, but also in disease-free countries. Diagnostics, vaccines, and therapeutics need to be developed, and therefore the establishment of animal models for EHF and MHF is invaluable. Several animal models have been developed for EHF and MHF using nonhuman primates (NHPs and rodents, which are crucial to understand pathophysiology and to develop diagnostics, vaccines, and therapeutics. Rhesus and cynomolgus macaques are representative models of filovirus infection as they exhibit remarkably similar symptoms to those observed in humans. However, the NHP models have practical and ethical problems that limit their experimental use. Furthermore, there are no inbred and genetically manipulated strains of NHP. Rodent models such as mouse, guinea pig, and hamster, have also been developed. However, these rodent models require adaptation of the virus to produce lethal disease and do not mirror all symptoms of human filovirus infection. This review article provides an outline of the clinical features of EHF and MHF in animals, including humans, and discusses how the animal models have been developed to study pathophysiology, vaccines, and therapeutics.

  5. Development of animal model for Chandipura virus in laboratory mice

    Institute of Scientific and Technical Information of China (English)

    Raut; CG; Jadi; RS; Chinchwale; AS; Daware; MM

    2005-01-01

    In recent years there was a outbreak of Chandipura virus(CHPV)in Sothern part of India causing encephalitis and acutedeathin children of age group of2.5months to15years withthe mortality rate of55.6%.As this disease is of acutedeath nature in humans no data available on pathogenesis.To understandthe pathogenesis of the disease caused by CHPV,experimental infection in laboratory swiss albino micewas conducted.Animals of age upto one weekfound highlysusceptible to all the routes of inoculation.For further stu...

  6. A noncovalent class of papain-like protease/deubiquitinase inhibitors blocks SARS virus replication

    Energy Technology Data Exchange (ETDEWEB)

    Ratia, Kiira; Pegan, Scott; Takayama, Jun; Sleeman, Katrina; Coughlin, Melissa; Baliji, Surendranath; Chaudhuri, Rima; Fu, Wentao; Prabhakar, Bellur S.; Johnson, Michael E.; Baker, Susan C.; Ghosh, Arun K.; Mesecar, Andrew D. (Loyola); (Purdue); (UIC)

    2008-10-27

    We report the discovery and optimization of a potent inhibitor against the papain-like protease (PLpro) from the coronavirus that causes severe acute respiratory syndrome (SARS-CoV). This unique protease is not only responsible for processing the viral polyprotein into its functional units but is also capable of cleaving ubiquitin and ISG15 conjugates and plays a significant role in helping SARS-CoV evade the human immune system. We screened a structurally diverse library of 50,080 compounds for inhibitors of PLpro and discovered a noncovalent lead inhibitor with an IC{sub 50} value of 20 {mu}M, which was improved to 600 nM via synthetic optimization. The resulting compound, GRL0617, inhibited SARS-CoV viral replication in Vero E6 cells with an EC{sub 50} of 15 {mu}M and had no associated cytotoxicity. The X-ray structure of PLpro in complex with GRL0617 indicates that the compound has a unique mode of inhibition whereby it binds within the S4-S3 subsites of the enzyme and induces a loop closure that shuts down catalysis at the active site. These findings provide proof-of-principle that PLpro is a viable target for development of antivirals directed against SARS-CoV, and that potent noncovalent cysteine protease inhibitors can be developed with specificity directed toward pathogenic deubiquitinating enzymes without inhibiting host DUBs.

  7. Animal Models for Influenza Viruses: Implications for Universal Vaccine Development

    Directory of Open Access Journals (Sweden)

    Irina Margine

    2014-10-01

    Full Text Available Influenza virus infections are a significant cause of morbidity and mortality in the human population. Depending on the virulence of the influenza virus strain, as well as the immunological status of the infected individual, the severity of the respiratory disease may range from sub-clinical or mild symptoms to severe pneumonia that can sometimes lead to death. Vaccines remain the primary public health measure in reducing the influenza burden. Though the first influenza vaccine preparation was licensed more than 60 years ago, current research efforts seek to develop novel vaccination strategies with improved immunogenicity, effectiveness, and breadth of protection. Animal models of influenza have been essential in facilitating studies aimed at understanding viral factors that affect pathogenesis and contribute to disease or transmission. Among others, mice, ferrets, pigs, and nonhuman primates have been used to study influenza virus infection in vivo, as well as to do pre-clinical testing of novel vaccine approaches. Here we discuss and compare the unique advantages and limitations of each model.

  8. Large Animal Models for Foamy Virus Vector Gene Therapy

    Directory of Open Access Journals (Sweden)

    Peter A. Horn

    2012-12-01

    Full Text Available Foamy virus (FV vectors have shown great promise for hematopoietic stem cell (HSC gene therapy. Their ability to efficiently deliver transgenes to multi-lineage long-term repopulating cells in large animal models suggests they will be effective for several human hematopoietic diseases. Here, we review FV vector studies in large animal models, including the use of FV vectors with the mutant O6-methylguanine-DNA methyltransferase, MGMTP140K to increase the number of genetically modified cells after transplantation. In these studies, FV vectors have mediated efficient gene transfer to polyclonal repopulating cells using short ex vivo transduction protocols designed to minimize the negative effects of ex vivo culture on stem cell engraftment. In this regard, FV vectors appear superior to gammaretroviral vectors, which require longer ex vivo culture to effect efficient transduction. FV vectors have also compared favorably with lentiviral vectors when directly compared in the dog model. FV vectors have corrected leukocyte adhesion deficiency and pyruvate kinase deficiency in the dog large animal model. FV vectors also appear safer than gammaretroviral vectors based on a reduced frequency of integrants near promoters and also near proto-oncogenes in canine repopulating cells. Together, these studies suggest that FV vectors should be highly effective for several human hematopoietic diseases, including those that will require relatively high percentages of gene-modified cells to achieve clinical benefit.

  9. Signs Observed Among Animal Species Infected with Raccoon Rabies Variant Virus, Massachusetts, USA, 1992–2010

    OpenAIRE

    Han, Linda L.; Vasil Pani; Sandra Smole; Werner, Barbara G.; Xingtai Wang

    2011-01-01

    Simple Summary We analyzed signs occurring among domestic and wild terrestrial animal species with raccoon rabies variant virus in Massachusetts, 1992–2010. While aggression is a useful predictor of rabies among wild animals, combinations of other signs such as ataxia, disorientation, and salivation are useful predictors of rabies among domestic animals. Abstract We analyzed signs occurring among domestic and wild terrestrial animal species infected with raccoon rabies variant virus (RRV) in ...

  10. Bats and SARS

    Centers for Disease Control (CDC) Podcasts

    2006-11-08

    Bats are a natural reservoir for emerging viruses, among them henipaviruses and rabies virus variants. Dr. Nina Marano, Chief, Geographic Medicine and Health Promotion Branch, Division of Global Migration and Quarantine, CDC, explains connection between horseshoe bats and SARS coronavirus transmission.  Created: 11/8/2006 by Emerging Infectious Diseases.   Date Released: 11/17/2006.

  11. Virus-like particles of SARS-like coronavirus formed by membrane proteins from different origins demonstrate stimulating activity in human dendritic cells.

    Directory of Open Access Journals (Sweden)

    Bingke Bai

    Full Text Available The pathogenesis of SARS coronavirus (CoV remains poorly understood. In the current study, two recombinant baculovirus were generated to express the spike (S protein of SARS-like coronavirus (SL-CoV isolated from bats (vAcBS and the envelope (E and membrane (M proteins of SARS-CoV, respectively. Co-infection of insect cells with these two recombinant baculoviruses led to self-assembly of virus-like particles (BVLPs as demonstrated by electron microscopy. Incorporation of S protein of vAcBS (BS into VLPs was confirmed by western blot and immunogold labeling. Such BVLPs up-regulated the level of CD40, CD80, CD86, CD83, and enhanced the secretion of IL-6, IL-10 and TNF-alpha in immature dendritic cells (DCs. Immune responses were compared in immature DCs inoculated with BVLPs or with VLPs formed by S, E and M proteins of human SARS-CoV. BVLPs showed a stronger ability to stimulate DCs in terms of cytokine induction as evidenced by 2 to 6 fold higher production of IL-6 and TNF-alpha. Further study indicated that IFN-gamma+ and IL-4+ populations in CD4+ T cells increased upon co-cultivation with DCs pre-exposed with BVLPs or SARS-CoV VLPs. The observed difference in DC-stimulating activity between BVLPs and SARS CoV VLPs was very likely due to the S protein. In agreement, SL-CoV S DNA vaccine evoked a more vigorous antibody response and a stronger T cell response than SARS-CoV S DNA in mice. Our data have demonstrated for the first time that SL-CoV VLPs formed by membrane proteins of different origins, one from SL-CoV isolated from bats (BS and the other two from human SARS-CoV (E and M, activated immature DCs and enhanced the expression of co-stimulatory molecules and the secretion of cytokines. Finding in this study may provide important information for vaccine development as well as for understanding the pathogenesis of SARS-like CoV.

  12. Serological evidence of hepatitis E virus infection in different animal species from the Southeast of Brazil

    OpenAIRE

    Cláudia L Vitral; Marcelo A Pinto; Lewis-Ximenez, Lia L.; Yuri E Khudyakov; Débora R dos Santos; Ana Maria C. Gaspar

    2005-01-01

    Serological evidence of hepatitis E virus infection (HEV) has been observed in both humans and different animal species living in non-endemic areas, suggesting that animals could be important reservoir for virus transmission to man. Antibodies to HEV have been detected in some Brazilian population groups. Nevertheless, sporadic cases of acute HEV infection have never been reported. We collected 271 serum samples from several domestic animals and also from pig handlers from Southeast of Brazil...

  13. Genetic Strategy to Prevent Influenza Virus Infections in Animals

    OpenAIRE

    Chen, Jianzhu; Chen, Steve C.-Y.; Stern, Patrick; Scott, Benjamin B; Lois, Carlos

    2008-01-01

    The natural reservoirs of influenza viruses are aquatic birds. After adaptation, avian viruses can acquire the ability to infect humans and cause severe disease. Because domestic poultry serves as a key link between the natural reservoir of influenza viruses and epidemics and pandemics in human populations, an effective measure to control influenza would be to eliminate or reduce influenza virus infection in domestic poultry. The development and distribution of influenza-resistant poultry rep...

  14. Animal Models for Influenza Virus Pathogenesis and Transmission

    OpenAIRE

    Lowen, Anice C.; Bouvier, Nicole M.

    2010-01-01

    Influenza virus infection of humans results in a respiratory disease that ranges in severity from sub-clinical infection to primary viral pneumonia that can result in death. The clinical effects of infection vary with the exposure history, age and immune status of the host, and also the virulence of the influenza strain. In humans, the virus is transmitted through either aerosol or contact-based transfer of infectious respiratory secretions. As is evidenced by most zoonotic influenza virus in...

  15. Viral hemorrhagic fevers of animals caused by positive-stranded RNA viruses

    Science.gov (United States)

    Here we outline serious diseases of wildlife, food and fiber animals, and non-human primates that cause damaging economic effects on producers all over the world. While some zoonotic viruses that occasionally cause serious disease and death in humans are mentioned, the positive sense RNA viruses ge...

  16. Coronavirus 3CL(pro) proteinase cleavage sites: Possible relevance to SARS virus pathology

    DEFF Research Database (Denmark)

    Kiemer, Lars; Lund, Ole; Brunak, Søren;

    2004-01-01

    . Prompted by this, we set out to analyse and predict cleavage by the coronavirus main proteinase using computational methods. Results: We retrieved sequence data on seven fully sequenced coronaviruses and identified the main 3CL proteinase cleavage sites in polyproteins using alignments. A neural network...... was trained to recognise the cleavage sites in the genomes obtaining a sensitivity of 87.0% and a specificity of 99.0%. Several proteins known to be cleaved by other viruses were submitted to prediction as well as proteins suspected relevant in coronavirus pathology. Cleavage sites were predicted in proteins...

  17. Animal Models for Influenza Viruses: Implications for Universal Vaccine Development

    OpenAIRE

    Irina Margine; Florian Krammer

    2014-01-01

    Influenza virus infections are a significant cause of morbidity and mortality in the human population. Depending on the virulence of the influenza virus strain, as well as the immunological status of the infected individual, the severity of the respiratory disease may range from sub-clinical or mild symptoms to severe pneumonia that can sometimes lead to death. Vaccines remain the primary public health measure in reducing the influenza burden. Though the first influenza vaccine preparation wa...

  18. Hendra and Nipah viruses: pathogenesis, animal models and recent breakthroughs in vaccination

    Directory of Open Access Journals (Sweden)

    Weingartl HM

    2015-09-01

    Full Text Available Hana M Weingartl National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB, Canada Abstract: Hendra and Nipah viruses are two highly pathogenic zoonotic members of the genus Henipavirus, family Paramyxoviridae, requiring work under biosafety level 4 conditions due to a lack of effective therapy and human vaccines. Several vaccine candidates were protective in animal models: recombinant vaccinia virus expressing Nipah virus (NiV F and G proteins in hamsters against NiV; recombinant ALVAC–NiV F and G in swine against NiV; recombinant Hendra virus (HeV soluble G protein (sGHeV against HeV and NiV in cats, ferrets, horses, and African green monkeys (AGM; recombinant vesicular stomatitis virus-based vectors expressing NiV F or G against NiV in hamsters and ferrets; measles virus-based NiV G vaccine candidate in hamsters and AGMs against NiV; and adenoassociated virus expressing NiG protein, which protected hamsters against NiV. The sGHeV was licensed for use in horses (Equivac HeV® in 2012. It is the first vaccine candidate licensed against a biosafety level 4 agent. With the development of suitable animal models (ferret, hamster and, importantly, AGM, progress can be made toward development of a human vaccine.Keywords: henipavirus, equine, swine, human infection, animal models, vaccine candidates

  19. Scope for using plant viruses to present epitopes from animal pathogens.

    Science.gov (United States)

    Porta; Lomonossoff

    1998-01-01

    Epitope presentation to the immune system for vaccination purposes can be achieved either via an inactivated or attenuated form of a pathogen or via its isolated antigenic sequences. When free, these peptides can adopt a variety of conformations, most of which will not exist in their native environment. Conjugation to carrier proteins restricts mobility of the peptides and increases their immunogenicity. A high local concentration of epitopes boosts the immune response further and can be generated by the use of self-aggregating carriers, such as the capsid proteins of viruses. In this regard plant viruses have in recent years started to make an impact as safer alternatives to the use of bacterial and attenuated animal viruses: the latter both require propagation in costly cell-culture systems where they can undergo reversion towards a virulent form and/or become contaminated by other pathogens. Plant virus-based vectors can be multiplied cheaply and to high yields (exceeding 1 mg/g plant tissue) in host plants. Both helical (tobacco mosaic virus, potato virus X, alfalfa mosaic virus) and icosahedral (cowpea mosaic virus, tomato bushy stunt virus) particles have been used to express a number of animal B-cell epitopes, whose immunogenic properties have been explored to varying degrees. Copyright 1998 John Wiley & Sons, Ltd. PMID:10398492

  20. 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.

  1. Gamma Radiation for Sterilizing the Carcasses of Foot-and-Mouth Disease Virus Infected Animals

    International Nuclear Information System (INIS)

    Experiments on sterilization by means of gamma rays of the carcasses of animals experimentally infected with foot-and-mouth disease virus (FMDV) have been carried out. In the first part the author studied the presence and survival of FMDV in the carcasses and in the organs of infected slaughtered animals. The results obtained are sufficient to underline the problem of the sterilization of carcasses of animals infected by FMDV. The experiments on the inactivation of the FMDV by gamma irradiation in vitro showed the same radiation sensitivity of the three types, O, A and C, of FMDV inaqueous solutions and showed that the fraction of surviving virus is an exponential function of the gamma-ray dose. The results obtained confirm the remarkable resistance of viruses to the effect of radiation. As far as the dry virus is concerned special tests indicated the necessity of greater doses for inactivating the same virus in the dry as opposed to the liquid state. In the third part the author studied the possibility of utilizing gamma rays for the sterilization of carcasses of infected (or suspected of being infected) FMDV animals using some tissues of infected animals (pigs) (blood, bone marrow, vertebrae, lymph nodes). The results obtained show that the inactivation of FMDV types O, A and C in the carcasses of infected animals can be made by treatment with gamma rays. (author)

  2. SARS Basics

    Science.gov (United States)

    ... Laboratory Testing & Specimens SARS-Associated Coronavirus (SARS-CoV) Sequencing Informed Consent for Laboratory Testing Specimen Collection and ... person touches a surface or object contaminated with infectious droplets and then touches his or her mouth, ...

  3. Antibodies to Berne virus in horses and other animals

    NARCIS (Netherlands)

    Horzinek, M.C.; Weiss, Marianne; Steck, F.; Kaderli, R.

    1984-01-01

    After inoculation into 2 foals, Berne virus induced neutralizing antibody, but did not cause clinical symptoms. In a horizontal study of seropositive mares and their offspring, a decline of maternal antibodies and a sudden synchronous seroconversion in all foals were observed, again without clinical

  4. Metagenomic analysis of viruses associated with field-grown and retail lettuce identifies human and animal viruses.

    Science.gov (United States)

    Aw, Tiong Gim; Wengert, Samantha; Rose, Joan B

    2016-04-16

    The emergence of culture- and sequence-independent metagenomic methods has not only provided great insight into the microbial community structure in a wide range of clinical and environmental samples but has also proven to be powerful tools for pathogen detection. Recent studies of the food microbiome have revealed the vast genetic diversity of bacteria associated with fresh produce. However, no work has been done to apply metagenomic methods to tackle viruses associated with fresh produce for addressing food safety. Thus, there is a little knowledge about the presence and diversity of viruses associated with fresh produce from farm-to-fork. To address this knowledge gap, we assessed viruses on commercial romaine and iceberg lettuces in fields and a produce distribution center using a shotgun metagenomic sequencing targeting both RNA and DNA viruses. Commercial lettuce harbors an immense assemblage of viruses that infect a wide range of hosts. As expected, plant pathogenic viruses dominated these communities. Sequences of rotaviruses and picobirnaviruses were also identified in both field-harvest and retail lettuce samples, suggesting an emerging foodborne transmission threat that has yet to be fully recognized. The identification of human and animal viruses in lettuce samples in the field emphasizes the importance of preventing viral contamination on leafy greens starting at the field. Although there are still some inherent experimental and bioinformatics challenges in applying viral metagenomic approaches for food safety testing, this work will facilitate further application of this unprecedented deep sequencing method to food samples. PMID:26894328

  5. Metagenomic analysis of viruses associated with field-grown and retail lettuce identifies human and animal viruses.

    Science.gov (United States)

    Aw, Tiong Gim; Wengert, Samantha; Rose, Joan B

    2016-04-16

    The emergence of culture- and sequence-independent metagenomic methods has not only provided great insight into the microbial community structure in a wide range of clinical and environmental samples but has also proven to be powerful tools for pathogen detection. Recent studies of the food microbiome have revealed the vast genetic diversity of bacteria associated with fresh produce. However, no work has been done to apply metagenomic methods to tackle viruses associated with fresh produce for addressing food safety. Thus, there is a little knowledge about the presence and diversity of viruses associated with fresh produce from farm-to-fork. To address this knowledge gap, we assessed viruses on commercial romaine and iceberg lettuces in fields and a produce distribution center using a shotgun metagenomic sequencing targeting both RNA and DNA viruses. Commercial lettuce harbors an immense assemblage of viruses that infect a wide range of hosts. As expected, plant pathogenic viruses dominated these communities. Sequences of rotaviruses and picobirnaviruses were also identified in both field-harvest and retail lettuce samples, suggesting an emerging foodborne transmission threat that has yet to be fully recognized. The identification of human and animal viruses in lettuce samples in the field emphasizes the importance of preventing viral contamination on leafy greens starting at the field. Although there are still some inherent experimental and bioinformatics challenges in applying viral metagenomic approaches for food safety testing, this work will facilitate further application of this unprecedented deep sequencing method to food samples.

  6. Companion Animals as a Source of Viruses for Human Beings and Food Production Animals

    NARCIS (Netherlands)

    Reperant, L.A.; Brown, I.H.; Haenen, O.L.M.; Jong, de M.D.; Osterhaus, Albert D.M.E.; Papa, A.; Rimstad, E.; Valarcher, J.F.; Kuiken, T.

    2016-01-01

    Companion animals comprise a wide variety of species, including dogs, cats, horses, ferrets, guinea pigs, reptiles, birds and ornamental fish, as well as food production animal species, such as domestic pigs, kept as companion animals. Despite their prominent place in human society, little is known

  7. Vaccination of Non-Domestic Animals against Emerging Virus Infections

    OpenAIRE

    Philippa, Joost

    2007-01-01

    markdownabstract__Abstract__ Since the 1980's, emerging and re-emerging infectious diseases have made an enormous impact on public and animal health, food supply, economies, and the environment. An estimated 75% of emerging infectious diseases in humans are zoonotic (pathogens of non-human vertebrate animals that may be transmitted to humans under natural conditions), mainly of viral origin and often vector-borne. Since 1980, more than 35 new infectious agents have emerged in humans , includi...

  8. Animal Models of Virus-Induced Neurobehavioral Sequelae: Recent Advances, Methodological Issues, and Future Prospects

    OpenAIRE

    Marco Bortolato; Sean C Godar

    2010-01-01

    Converging lines of clinical and epidemiological evidence suggest that viral infections in early developmental stages may be a causal factor in neuropsychiatric disorders such as schizophrenia, bipolar disorder, and autism-spectrum disorders. This etiological link, however, remains controversial in view of the lack of consistent and reproducible associations between viruses and mental illness. Animal models of virus-induced neurobehavioral disturbances afford powerful tools to test etiologica...

  9. Antigenic typing of brazilian rabies virus samples isolated from animals and humans, 1989-2000

    OpenAIRE

    FAVORETTO Silvana Regina; Carrieri, Maria Luiza; CUNHA Elenice Maria S.; Elizabeth A.C. Aguiar; SILVA Luzia Helena Q.; Miriam M. SODRÉ; SOUZA Maria Conceição A.M.; Kotait, Ivanete

    2002-01-01

    Animal and human rabies samples isolated between 1989 and 2000 were typified by means of a monoclonal antibody panel against the viral nucleoprotein. The panel had been previously established to study the molecular epidemiology of rabies virus in the Americas. Samples were isolated in the Diagnostic Laboratory of the Pasteur Institute and in other rabies diagnostic centers in Brazil. In addition to the fixed virus samples CVS-31/96-IP, preserved in mouse brain, and PV-BHK/97, preserved in cel...

  10. Vaccination of Non-Domestic Animals against Emerging Virus Infections

    NARCIS (Netherlands)

    J.D.W. Philippa (Joost)

    2007-01-01

    markdownabstract__Abstract__ Since the 1980's, emerging and re-emerging infectious diseases have made an enormous impact on public and animal health, food supply, economies, and the environment. An estimated 75% of emerging infectious diseases in humans are zoonotic (pathogens of non-human vertebra

  11. Radiation inactivation of animal viruses in culture fluid and sewage; a case study

    International Nuclear Information System (INIS)

    Inactivation studies of different animal viruses were performed with gamma irradiation from a 60Co-source to evaluate the technical and economic feasibility of sterilization of sewage of a veterinary institute involved in research on virus diseases and the production of virus vaccines. The D10 values for swine fever virus, foot-and-mouth disease virus (FMDV) and swine vesicular disease virus (SVDV) irradiated in culture medium at 0degC were 1.8, 4.5, and 5.9 kGy (0.18, 0.45, and 0.59 Mrad), respectively. Suspensions of SVDV and FMDV were mixed with raw sludge and irradiated at 8degC. Raw sludge had a protecting effect on FMDV, if compared to culture fluid, increasing the D10 value significantly to 6.5 kGy (0.65 Mrad). No similar protective effect was observed in the case of SVDV. Addition of 0.2 M NaBr did not significantly increase the radiosensitivity of these two viruses. The technical and economic feasibility for sterilization of sewage and sludge by 60Co-gamma irradiation are discussed

  12. Transfection of RNA from organ samples of infected animals represents a highly sensitive method for virus detection and recovery of classical swine fever virus.

    Directory of Open Access Journals (Sweden)

    Denise Meyer

    Full Text Available Translation and replication of positive stranded RNA viruses are directly initiated in the cellular cytoplasm after uncoating of the viral genome. Accordingly, infectious virus can be generated by transfection of RNA genomes into susceptible cells. In the present study, efficiency of conventional virus isolation after inoculation of cells with infectious sample material was compared to virus recovery after transfection of total RNA derived from organ samples of pigs infected with Classical swine fever virus (CSFV. Compared to the conventional method of virus isolation applied in three different porcine cell lines used in routine diagnosis of CSF, RNA transfection showed a similar efficiency for virus rescue. For two samples, recovery of infectious virus was only possible by RNA transfection, but not by the classical approach of virus isolation. Therefore, RNA transfection represents a valuable alternative to conventional virus isolation in particular when virus isolation is not possible, sample material is not suitable for virus isolation or when infectious material is not available. To estimate the potential risk of RNA prepared from sample material for infection of pigs, five domestic pigs were oronasally inoculated with RNA that was tested positive for virus rescue after RNA transfection. This exposure did not result in viral infection or clinical disease of the animals. In consequence, shipment of CSFV RNA can be regarded as a safe alternative to transportation of infectious virus and thereby facilitates the exchange of virus isolates among authorized laboratories with appropriate containment facilities.

  13. Sample size considerations for one-to-one animal transmission studies of the influenza A viruses.

    Directory of Open Access Journals (Sweden)

    Hiroshi Nishiura

    Full Text Available BACKGROUND: Animal transmission studies can provide important insights into host, viral and environmental factors affecting transmission of viruses including influenza A. The basic unit of analysis in typical animal transmission experiments is the presence or absence of transmission from an infectious animal to a susceptible animal. In studies comparing two groups (e.g. two host genetic variants, two virus strains, or two arrangements of animal cages, differences between groups are evaluated by comparing the proportion of pairs with successful transmission in each group. The present study aimed to discuss the significance and power to estimate transmissibility and identify differences in the transmissibility based on one-to-one trials. The analyses are illustrated on transmission studies of influenza A viruses in the ferret model. METHODOLOGY/PRINCIPAL FINDINGS: Employing the stochastic general epidemic model, the basic reproduction number, R₀, is derived from the final state of an epidemic and is related to the probability of successful transmission during each one-to-one trial. In studies to estimate transmissibility, we show that 3 pairs of infectious/susceptible animals cannot demonstrate a significantly higher transmissibility than R₀= 1, even if infection occurs in all three pairs. In comparisons between two groups, at least 4 pairs of infectious/susceptible animals are required in each group to ensure high power to identify significant differences in transmissibility between the groups. CONCLUSIONS: These results inform the appropriate sample sizes for animal transmission experiments, while relating the observed proportion of infected pairs to R₀, an interpretable epidemiological measure of transmissibility. In addition to the hypothesis testing results, the wide confidence intervals of R₀ with small sample sizes also imply that the objective demonstration of difference or similarity should rest on firmly calculated sample size.

  14. An outbreak of canine distemper virus in tigers (Panthera tigris): possible transmission from wild animals to zoo animals.

    Science.gov (United States)

    Nagao, Yumiko; Nishio, Yohei; Shiomoda, Hiroshi; Tamaru, Seiji; Shimojima, Masayuki; Goto, Megumi; Une, Yumi; Sato, Azusa; Ikebe, Yusuke; Maeda, Ken

    2012-06-01

    Canine distemper virus (CDV), a morbillivirus that causes one of the most contagious and lethal viral diseases known in canids, has an expanding host range, including wild animals. Since December 2009, several dead or dying wild raccoon dogs (Nyctereutes procyonoides) were found in and around one safari-style zoo in Japan, and CDV was isolated from four of these animals. In the subsequent months (January to February 2010), 12 tigers (Panthera tigris) in the zoo developed respiratory and gastrointestinal diseases, and CDV RNA was detected in fecal samples of the examined tigers. In March 2010, one of the tigers developed a neurological disorder and died; CDV was isolated from the lung of this animal. Sequence analysis of the complete hemagglutinin (H) gene and the signal peptide region of the fusion (F) gene showed high homology among these isolates (99.8-100%), indicating that CDV might have been transmitted from raccoon dog to tiger. In addition, these isolates belonged to genotype Asia-1 and had lower homology (zoo and wild bears (Ursus thibetanus) captured around this area supported the theory that a CDV epidemic had occurred in many mammal species in and around the zoo. These results indicate a risk of CDV transmission among many animal species, including large felids and endangered species.

  15. The spike protein of severe acute respiratory syndrome (SARS) is cleaved in virus infected Vero-E6 cells

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Spike protein is one of the major structural proteins of severe acute respiratory syndrome-coronavirus. It is essential for the interaction of the virons with host cell receptors and subsequent fusion of the viral envelop with host cell membrane to allow infection. Some spike proteins of coronavirus, such as MHV, HCoV-OC43, AIBV and BcoV, are proteolytically cleaved into two subunits, S1 and S2. In contrast, TGV, FIPV and HCoV-229E are not. Many studies have shown that the cleavage of spike protein seriously affects its function. In order to investigate the maturation and proteolytic processing of the S protein of SARS CoV, we generated S1 and S2 subunit specific antibodies (Abs) as well as N, E and 3CL protein-specific Abs. Our results showed that the antibodies could efficiently and specifically bind to their corresponding proteins from E. coli expressed or lysate of SARS-CoV infected Vero-E6 cells by Western blot analysis. Furthermore, the anti-S 1 and S2 Abs were proved to be capable of binding to SARS CoV under electron microscope observation. When S2 Ab was used to perform immune precipitation with lysate of SARS-CoV infected cells, a cleaved S2 fragment was detected with S2-specific mAb by Western blot analysis. The data demonstrated that the cleavage of S protein was observed in the lysate, indicating that proteolytic processing of S protein is present in host cells.

  16. Signs Observed Among Animal Species Infected with Raccoon Rabies Variant Virus, Massachusetts, USA, 1992–2010

    Directory of Open Access Journals (Sweden)

    Linda L. Han

    2011-11-01

    Full Text Available We analyzed signs occurring among domestic and wild terrestrial animal species infected with raccoon rabies variant virus (RRV in Massachusetts, 1992–2010. The clinical sign of aggression was significantly associated with rabid stray cats (odds ratio, OR = 2.3 and RRV affected major wild terrestrial animal species individually, which included raccoons (OR = 2.8, skunks (OR = 8.0, gray foxes (OR = 21.3, red foxes (OR = 10.4, woodchucks (OR = 4.7 and coyotes (OR = 27.6. While aggression is a useful predictor of rabies among wild animals, combinations of other signs such as ataxia, disorientation, and salivation are useful predictors of rabies among domestic animals. Pets reported with multiple clinical signs had significantly higher rabies positive testing result than those reported with single clinical sign (p < 0.001. The result suggested the importance of avoiding aggressive terrestrial wild animals and giving additional attention to pets with multiple clinical signs.

  17. Mission critical: mobilization of essential animal models for Ebola, Nipah, and Machupo virus infections.

    Science.gov (United States)

    Zumbrun, E E

    2015-01-01

    The reports for Ebola virus Zaire (EBOV), Nipah virus, and Machupo virus (MACV) pathogenesis, in this issue of Veterinary Pathology, are timely considering recent events, both nationally and internationally. EBOV, Nipah virus, and MACV cause highly lethal infections for which no Food and Drug Administration (FDA) licensed vaccines or therapies exist. Not only are there concerns that these agents could be used by those with malicious intent, but shifts in ecological distribution of viral reservoirs due to climate change or globalization could lead to more frequent infections within remote regions than previously seen as well as outbreaks in more populous areas. The current EBOV epidemic shows no sign of abating across 3 West African nations (as of October 2014), including densely populated areas, far outpacing infection rates of previous outbreaks. A limited number of cases have also arisen in the United States and Europe. With few treatment options for these deadly viruses, development of animal models reflective of human disease is paramount to combat these diseases. As an example of this potential, a new treatment compound, ZMapp, that had demonstrated efficacy against EBOV infection in nonhuman primates (NHPs) received an emergency compassionate use exception from the FDA for the treatment of 2 American medical workers infected with EBOV, and they are currently virus free and recovering.

  18. Morbillivirus Experimental Animal Models: Measles Virus Pathogenesis Insights from Canine Distemper Virus

    Directory of Open Access Journals (Sweden)

    Renata da Fontoura Budaszewski

    2016-10-01

    Full Text Available Morbilliviruses share considerable structural and functional similarities. Even though disease severity varies among the respective host species, the underlying pathogenesis and the clinical signs are comparable. Thus, insights gained with one morbillivirus often apply to the other members of the genus. Since the Canine distemper virus (CDV causes severe and often lethal disease in dogs and ferrets, it is an attractive model to characterize morbillivirus pathogenesis mechanisms and to evaluate the efficacy of new prophylactic and therapeutic approaches. This review compares the cellular tropism, pathogenesis, mechanisms of persistence and immunosuppression of the Measles virus (MeV and CDV. It then summarizes the contributions made by studies on the CDV in dogs and ferrets to our understanding of MeV pathogenesis and to vaccine and drugs development.

  19. Human monoclonal antibody combination against SARS coronavirus: synergy and coverage of escape mutants.

    Directory of Open Access Journals (Sweden)

    Jan ter Meulen

    2006-07-01

    Full Text Available BACKGROUND: Experimental animal data show that protection against severe acute respiratory syndrome coronavirus (SARS-CoV infection with human monoclonal antibodies (mAbs is feasible. For an effective immune prophylaxis in humans, broad coverage of different strains of SARS-CoV and control of potential neutralization escape variants will be required. Combinations of virus-neutralizing, noncompeting mAbs may have these properties. METHODS AND FINDINGS: Human mAb CR3014 has been shown to completely prevent lung pathology and abolish pharyngeal shedding of SARS-CoV in infected ferrets. We generated in vitro SARS-CoV variants escaping neutralization by CR3014, which all had a single P462L mutation in the glycoprotein spike (S of the escape virus. In vitro experiments confirmed that binding of CR3014 to a recombinant S fragment (amino acid residues 318-510 harboring this mutation was abolished. We therefore screened an antibody-phage library derived from blood of a convalescent SARS patient for antibodies complementary to CR3014. A novel mAb, CR3022, was identified that neutralized CR3014 escape viruses, did not compete with CR3014 for binding to recombinant S1 fragments, and bound to S1 fragments derived from the civet cat SARS-CoV-like strain SZ3. No escape variants could be generated with CR3022. The mixture of both mAbs showed neutralization of SARS-CoV in a synergistic fashion by recognizing different epitopes on the receptor-binding domain. Dose reduction indices of 4.5 and 20.5 were observed for CR3014 and CR3022, respectively, at 100% neutralization. Because enhancement of SARS-CoV infection by subneutralizing antibody concentrations is of concern, we show here that anti-SARS-CoV antibodies do not convert the abortive infection of primary human macrophages by SARS-CoV into a productive one. CONCLUSIONS: The combination of two noncompeting human mAbs CR3014 and CR3022 potentially controls immune escape and extends the breadth of protection. At

  20. Animal models for the study of hepatitis C virus infection and related liver disease

    DEFF Research Database (Denmark)

    Bukh, Jens

    2012-01-01

    Hepatitis C virus (HCV) causes liver-related death in more than 300,000 people annually. Treatments for patients with chronic HCV are suboptimal, despite the introduction of directly acting antiviral agents. There is no vaccine that prevents HCV infection. Relevant animal models are important...... for HCV research and development of drugs and vaccines. Chimpanzees are the best model for studies of HCV infection and related innate and adaptive host immune responses. They can be used in immunogenicity and efficacy studies of HCV vaccines. The only small animal models of robust HCV infection are T......- and B- cell deficient mice with human chimeric livers. Although these mice cannot be used in studies of adaptive immunity, they have provided new insights into HCV neutralization, interactions between virus and receptors, innate host responses, and therapeutic approaches. Recent progress in developing...

  1. Animal models for the study of hepatitis C virus infection and replication

    Institute of Scientific and Technical Information of China (English)

    Kristin L MacArthur; Catherine H Wu; George Y Wu

    2012-01-01

    Hepatitis C virus (HCV) hepatitis,initially termed non-A,non-B hepatitis,has become one of the leading causes of cirrhosis and hepatocellular carcinoma worldwide.With the help of animal models,our understanding of the virus has grown substantially from the time of initial discovery.There is a paucity of available animal models for the study of HCV,mainly because of the selective susceptibility limited to humans and primates.Recent work has focused modification of animals to permit HCV entry,replication and transmission.In this review,we highlight the currently available models for the study of HCV including chimpanzees,tupaia,mouse and rat models.Discussion will include methods of model design as well as the advantages and disadvantages of each model.Particular focus is dedicated to knowledge of pathophysiologic mechanisms of HCV infection that have been elucidated through animal studies.Research within animal models is critically important to establish a complete understanding of HCV infection,which will ultimately form the basis for future treatments and prevention of disease.

  2. The pig as a large animal model for influenza a virus infection

    OpenAIRE

    Skovgaard, Kerstin; Brogaard, Louise; Larsen, Lars Erik; Mortensen, S.(Niels Bohr Institute, University of Copenhagen, Kobenhavn, Denmark); Dürrwald, R; Schengel, M.; Peter M H Heegaard

    2015-01-01

    It is increasingly realized that large animal models like the pig are exceptionally human like and serve as an excellent model for disease and inflammation. Pigs are fully susceptible to human influenza, share many similarities with humans regarding lung physiology and innate immune cell infiltration of the respiratory system.This study aimed at providing a better understanding of the involvement of innate immune factors and non-coding RNA in blood leukocytes during influenza A virus infectio...

  3. Illumination of parainfluenza virus infection and transmission in living animals reveals a tissue-specific dichotomy.

    Directory of Open Access Journals (Sweden)

    Crystal W Burke

    2011-07-01

    Full Text Available The parainfluenza viruses (PIVs are highly contagious respiratory paramyxoviruses and a leading cause of lower respiratory tract (LRT disease. Since no vaccines or antivirals exist, non-pharmaceutical interventions are the only means of control for these pathogens. Here we used bioluminescence imaging to visualize the spatial and temporal progression of murine PIV1 (Sendai virus infection in living mice after intranasal inoculation or exposure by contact. A non-attenuated luciferase reporter virus (rSeV-luc(M-F* that expressed high levels of luciferase yet was phenotypically similar to wild-type Sendai virus in vitro and in vivo was generated to allow visualization. After direct intranasal inoculation, we unexpectedly observed that the upper respiratory tract (URT and trachea supported robust infection under conditions that result in little infection or pathology in the lungs including a low inoculum of virus, an attenuated virus, and strains of mice genetically resistant to lung infection. The high permissivity of the URT and trachea to infection resulted in 100% transmission to naïve contact recipients, even after low-dose (70 PFU inoculation of genetically resistant BALB/c donor mice. The timing of transmission was consistent with the timing of high viral titers in the URT and trachea of donor animals but was independent of the levels of infection in the lungs of donors. The data therefore reveals a disconnect between transmissibility, which is associated with infection in the URT, and pathogenesis, which arises from infection in the lungs and the immune response. Natural infection after transmission was universally robust in the URT and trachea yet limited in the lungs, inducing protective immunity without weight loss even in genetically susceptible 129/SvJ mice. Overall, these results reveal a dichotomy between PIV infection in the URT and trachea versus the lungs and define a new model for studies of pathogenesis, development of live

  4. VIRUS VACCINE RESEARCH AT THE NATIONAL ANIMAL DISEASE CENTER: LESSONS FROM SWINE INFLUENZA VIRUS AND BOVINE VIRAL DIARRHEA VIRUS

    Science.gov (United States)

    The continuing emergence of novel subtypes and genetic variants of swine influenza viruses (SIV) causing swine flu challenges our ability to effectively manage this high morbidity disease among swine. New strategic approaches for vaccine development must be considered to keep up with the ever-evolv...

  5. Hepatitis C virus infection and related liver disease: the quest for the best animal model

    Directory of Open Access Journals (Sweden)

    Laurent eMailly

    2013-07-01

    Full Text Available Hepatitis C virus (HCV is a major cause of cirrhosis and hepatocellular carcinoma (HCC making the virus the most common cause of liver failure and transplantation. HCV is estimated to chronically affect 130 million individuals and to lead to more than 350,000 deaths per year worldwide. A vaccine is currently not available. The recently developed direct acting antivirals (DAAs have markedly increased the efficacy of the standard of care but are not efficient enough to completely cure all chronically infected patients and their toxicity limits their use in patients with advanced liver disease, co-morbidity or transplant recipients. Because of the host restriction, which is limited to humans and non-human primates, in vivo study of HCV infection has been hampered since its discovery more than 20 years ago. The chimpanzee remains the most physiological model to study the innate and adaptive immune responses, but its use is ethically difficult and is now very restricted and regulated. The development of a small animal model that allows robust HCV infection has been achieved using chimeric liver immunodeficient mice, which are therefore not suitable for studying the adaptive immune responses. Nevertheless, these models allowed to go deeply in the comprehension of virus-host interactions and to assess different therapeutic approaches. The immunocompetent mouse models that were recently established by genetic humanization have shown an interesting improvement concerning the study of the immune responses but are still limited by the absence of the complete robust life cycle of the virus. In this review, we will focus on the relevant available animal models of HCV infection and their usefulness for deciphering the HCV life cycle and virus-induced liver disease, as well as for the development and evaluation of new therapeutics. We will also discuss the perspectives on future immunocompetent mouse models and the hurdles to their development.

  6. Seroepidemiological Studies of Crimean-Congo Hemorrhagic Fever Virus in Domestic and Wild Animals.

    Science.gov (United States)

    Spengler, Jessica R; Bergeron, Éric; Rollin, Pierre E

    2016-01-01

    Crimean-Congo hemorrhagic fever (CCHF) is a widely distributed, tick-borne viral disease. Humans are the only species known to develop illness after CCHF virus (CCHFV) infection, characterized by a nonspecific febrile illness that can progress to severe, often fatal, hemorrhagic disease. A variety of animals may serve as asymptomatic reservoirs of CCHFV in an endemic cycle of transmission. Seroepidemiological studies have been instrumental in elucidating CCHFV reservoirs and in determining endemic foci of viral transmission. Herein, we review over 50 years of CCHFV seroepidemiological studies in domestic and wild animals. This review highlights the role of livestock in the maintenance and transmission of CCHFV, and provides a detailed summary of seroepidemiological studies of wild animal species, reflecting their relative roles in CCHFV ecology.

  7. Serological evidence of hepatitis E virus infection in different animal species from the Southeast of Brazil

    Directory of Open Access Journals (Sweden)

    Cláudia L Vitral

    2005-04-01

    Full Text Available Serological evidence of hepatitis E virus infection (HEV has been observed in both humans and different animal species living in non-endemic areas, suggesting that animals could be important reservoir for virus transmission to man. Antibodies to HEV have been detected in some Brazilian population groups. Nevertheless, sporadic cases of acute HEV infection have never been reported. We collected 271 serum samples from several domestic animals and also from pig handlers from Southeast of Brazil in order to investigate the seroprevalence of HEV infection. Anti-HEV IgG was detected in cows (1.42%, dogs (6.97%, chickens (20%, swines (24.3%, and rodents (50%, as well as in pig handlers (6.3%. The recognition of swine HEV infections in pigs in many countries of the world led us to investigate a larger sample of pigs (n = 357 from the same Brazilian region with ages ranging from 1 to > 25 weeks. IgG anti-HEV was detected in 100% of 7-day old pigs. Following a gradual decline between weeks 2 and 8 (probably due to loss of maternal IgG, the prevalence then steady increased until it reached 97.3% of animals older than 25 weeks. Besides the detection of anti-HEV antibodies in different animal species, the results showed that swine HEV infection seems to be almost universal within this Brazilian pig population. This is the first report that shows evidences of HEV circulation in Brazilian animal species and pig handlers.

  8. Serological evidence of hepatitis E virus infection in different animal species from the Southeast of Brazil.

    Science.gov (United States)

    Vitral, Cláudia L; Pinto, Marcelo A; Lewis-Ximenez, Lia L; Khudyakov, Yuri E; dos Santos, Débora R; Gaspar, Ana Maria C

    2005-04-01

    Serological evidence of hepatitis E virus infection (HEV) has been observed in both humans and different animal species living in non-endemic areas, suggesting that animals could be important reservoir for virus transmission to man. Antibodies to HEV have been detected in some Brazilian population groups. Nevertheless, sporadic cases of acute HEV infection have never been reported. We collected 271 serum samples from several domestic animals and also from pig handlers from Southeast of Brazil in order to investigate the seroprevalence of HEV infection. Anti-HEV IgG was detected in cows (1.42%), dogs (6.97%), chickens (20%), swines (24.3%), and rodents (50%), as well as in pig handlers (6.3%). The recognition of swine HEV infections in pigs in many countries of the world led us to investigate a larger sample of pigs (n = 357) from the same Brazilian region with ages ranging from 1 to > 25 weeks. IgG anti-HEV was detected in 100% of 7-day old pigs. Following a gradual decline between weeks 2 and 8 (probably due to loss of maternal IgG), the prevalence then steady increased until it reached 97.3% of animals older than 25 weeks. Besides the detection of anti-HEV antibodies in different animal species, the results showed that swine HEV infection seems to be almost universal within this Brazilian pig population. This is the first report that shows evidences of HEV circulation in Brazilian animal species and pig handlers. PMID:16021297

  9. Vaccine efficacy in senescent mice challenged with recombinant SARS-CoV bearing epidemic and zoonotic spike variants.

    Directory of Open Access Journals (Sweden)

    Damon Deming

    2006-12-01

    Full Text Available BACKGROUND: In 2003, severe acute respiratory syndrome coronavirus (SARS-CoV was identified as the etiological agent of severe acute respiratory syndrome, a disease characterized by severe pneumonia that sometimes results in death. SARS-CoV is a zoonotic virus that crossed the species barrier, most likely originating from bats or from other species including civets, raccoon dogs, domestic cats, swine, and rodents. A SARS-CoV vaccine should confer long-term protection, especially in vulnerable senescent populations, against both the 2003 epidemic strains and zoonotic strains that may yet emerge from animal reservoirs. We report the comprehensive investigation of SARS vaccine efficacy in young and senescent mice following homologous and heterologous challenge. METHODS AND FINDINGS: Using Venezuelan equine encephalitis virus replicon particles (VRP expressing the 2003 epidemic Urbani SARS-CoV strain spike (S glycoprotein (VRP-S or the nucleocapsid (N protein from the same strain (VRP-N, we demonstrate that VRP-S, but not VRP-N vaccines provide complete short- and long-term protection against homologous strain challenge in young and senescent mice. To test VRP vaccine efficacy against a heterologous SARS-CoV, we used phylogenetic analyses, synthetic biology, and reverse genetics to construct a chimeric virus (icGDO3-S encoding a synthetic S glycoprotein gene of the most genetically divergent human strain, GDO3, which clusters among the zoonotic SARS-CoV. icGD03-S replicated efficiently in human airway epithelial cells and in the lungs of young and senescent mice, and was highly resistant to neutralization with antisera directed against the Urbani strain. Although VRP-S vaccines provided complete short-term protection against heterologous icGD03-S challenge in young mice, only limited protection was seen in vaccinated senescent animals. VRP-N vaccines not only failed to protect from homologous or heterologous challenge, but resulted in enhanced

  10. Animal Models of Virus-Induced Neurobehavioral Sequelae: Recent Advances, Methodological Issues, and Future Prospects

    Directory of Open Access Journals (Sweden)

    Marco Bortolato

    2010-01-01

    Full Text Available Converging lines of clinical and epidemiological evidence suggest that viral infections in early developmental stages may be a causal factor in neuropsychiatric disorders such as schizophrenia, bipolar disorder, and autism-spectrum disorders. This etiological link, however, remains controversial in view of the lack of consistent and reproducible associations between viruses and mental illness. Animal models of virus-induced neurobehavioral disturbances afford powerful tools to test etiological hypotheses and explore pathophysiological mechanisms. Prenatal or neonatal inoculations of neurotropic agents (such as herpes-, influenza-, and retroviruses in rodents result in a broad spectrum of long-term alterations reminiscent of psychiatric abnormalities. Nevertheless, the complexity of these sequelae often poses methodological and interpretational challenges and thwarts their characterization. The recent conceptual advancements in psychiatric nosology and behavioral science may help determine new heuristic criteria to enhance the translational value of these models. A particularly critical issue is the identification of intermediate phenotypes, defined as quantifiable factors representing single neurochemical, neuropsychological, or neuroanatomical aspects of a diagnostic category. In this paper, we examine how the employment of these novel concepts may lead to new methodological refinements in the study of virus-induced neurobehavioral sequelae through animal models.

  11. Feline Foamy Virus-Based Vectors: Advantages of an Authentic Animal Model

    Directory of Open Access Journals (Sweden)

    Martin Löchelt

    2013-07-01

    Full Text Available New-generation retroviral vectors have potential applications in vaccination and gene therapy. Foamy viruses are particularly interesting as vectors, because they are not associated to any disease. Vector research is mainly based on primate foamy viruses (PFV, but cats are an alternative animal model, due to their smaller size and the existence of a cognate feline foamy virus (FFV. The potential of replication-competent (RC FFV vectors for vaccination and replication-deficient (RD FFV-based vectors for gene delivery purposes has been studied over the past years. In this review, the key achievements and functional evaluation of the existing vectors from in vitro cell culture systems to out-bred cats will be described. The data presented here demonstrate the broad application spectrum of FFV-based vectors, especially in pathogen-specific prophylactic and therapeutic vaccination using RD vectors in cats and in classical gene delivery. In the cat-based system, FFV-based vectors provide an advantageous platform to evaluate and optimize the applicability, efficacy and safety of foamy virus (FV vectors, especially the understudied aspect of FV cell and organ tropism.

  12. Yeast based small molecule screen for inhibitors of SARS-CoV.

    Directory of Open Access Journals (Sweden)

    Matthew Frieman

    Full Text Available Severe acute respiratory coronavirus (SARS-CoV emerged in 2002, resulting in roughly 8000 cases worldwide and 10% mortality. The animal reservoirs for SARS-CoV precursors still exist and the likelihood of future outbreaks in the human population is high. The SARS-CoV papain-like protease (PLP is an attractive target for pharmaceutical development because it is essential for virus replication and is conserved among human coronaviruses. A yeast-based assay was established for PLP activity that relies on the ability of PLP to induce a pronounced slow-growth phenotype when expressed in S. cerevisiae. Induction of the slow-growth phenotype was shown to take place over a 60-hour time course, providing the basis for conducting a screen for small molecules that restore growth by inhibiting the function of PLP. Five chemical suppressors of the slow-growth phenotype were identified from the 2000 member NIH Diversity Set library. One of these, NSC158362, potently inhibited SARS-CoV replication in cell culture without toxic effects on cells, and it specifically inhibited SARS-CoV replication but not influenza virus replication. The effect of NSC158362 on PLP protease, deubiquitinase and anti-interferon activities was investigated but the compound did not alter these activities. Another suppressor, NSC158011, demonstrated the ability to inhibit PLP protease activity in a cell-based assay. The identification of these inhibitors demonstrated a strong functional connection between the PLP-based yeast assay, the inhibitory compounds, and SARS-CoV biology. Furthermore the data with NSC158362 suggest a novel mechanism for inhibition of SARS-CoV replication that may involve an unknown activity of PLP, or alternatively a direct effect on a cellular target that modifies or bypasses PLP function in yeast and mammalian cells.

  13. OpenFluDB, a database for human and animal influenza virus

    OpenAIRE

    Liechti, Robin; Gleizes, Anne; Kuznetsov, Dmitry; Bougueleret, Lydie; Le Mercier, Philippe; Bairoch, Amos Marc; Xenarios, Ioannis

    2010-01-01

    Although research on influenza lasted for more than 100 years, it is still one of the most prominent diseases causing half a million human deaths every year. With the recent observation of new highly pathogenic H5N1 and H7N7 strains, and the appearance of the influenza pandemic caused by the H1N1 swine-like lineage, a collaborative effort to share observations on the evolution of this virus in both animals and humans has been established. The OpenFlu database (OpenFluDB) is a part of this col...

  14. Antigenic typing of brazilian rabies virus samples isolated from animals and humans, 1989-2000

    Directory of Open Access Journals (Sweden)

    FAVORETTO Silvana Regina

    2002-01-01

    Full Text Available Animal and human rabies samples isolated between 1989 and 2000 were typified by means of a monoclonal antibody panel against the viral nucleoprotein. The panel had been previously established to study the molecular epidemiology of rabies virus in the Americas. Samples were isolated in the Diagnostic Laboratory of the Pasteur Institute and in other rabies diagnostic centers in Brazil. In addition to the fixed virus samples CVS-31/96-IP, preserved in mouse brain, and PV-BHK/97, preserved in cell culture, a total of 330 rabies virus samples were isolated from dogs, cats, cattle, horses, bats, sheep, goat, swine, foxes, marmosets, coati and humans. Six antigenic variants that were compatible with the pre-established monoclonal antibodies panel were defined: numbers 2 (dog, 3 (Desmodus rotundus, 4 (Tadarida brasiliensis, 5 (vampire bat from Venezuela, 6 (Lasiurus cinereus and Lab (reacted to all used antibodies. Six unknown profiles, not compatible with the panel, were also found. Samples isolated from insectivore bats showed the greatest variability and the most commonly isolated variant was variant-3 (Desmodus rotundus. These findings may be related to the existence of multiple independent transmission cycles, involving different bat species.

  15. Ferrets as a Novel Animal Model for Studying Human Respiratory Syncytial Virus Infections in Immunocompetent and Immunocompromised Hosts

    Directory of Open Access Journals (Sweden)

    Koert J. Stittelaar

    2016-06-01

    Full Text Available Human respiratory syncytial virus (HRSV is an important cause of severe respiratory tract disease in immunocompromised patients. Animal models are indispensable for evaluating novel intervention strategies in this complex patient population. To complement existing models in rodents and non-human primates, we have evaluated the potential benefits of an HRSV infection model in ferrets (Mustela putorius furo. Nine- to 12-month-old HRSV-seronegative immunocompetent or immunocompromised ferrets were infected with a low-passage wild-type strain of HRSV subgroup A (105 TCID50 administered by intra-tracheal or intra-nasal inoculation. Immune suppression was achieved by bi-daily oral administration of tacrolimus, mycophenolate mofetil, and prednisolone. Throat and nose swabs were collected daily and animals were euthanized four, seven, or 21 days post-infection (DPI. Virus loads were determined by quantitative virus culture and qPCR. We observed efficient HRSV replication in both the upper and lower respiratory tract. In immunocompromised ferrets, virus loads reached higher levels and showed delayed clearance as compared to those in immunocompetent animals. Histopathological evaluation of animals euthanized 4 DPI demonstrated that the virus replicated in the respiratory epithelial cells of the trachea, bronchi, and bronchioles. These animal models can contribute to an assessment of the efficacy and safety of novel HRSV intervention strategies.

  16. Ferrets as a Novel Animal Model for Studying Human Respiratory Syncytial Virus Infections in Immunocompetent and Immunocompromised Hosts

    Science.gov (United States)

    Stittelaar, Koert J.; de Waal, Leon; van Amerongen, Geert; Veldhuis Kroeze, Edwin J.B.; Fraaij, Pieter L.A.; van Baalen, Carel A.; van Kampen, Jeroen J.A.; van der Vries, Erhard; Osterhaus, Albert D.M.E.; de Swart, Rik L.

    2016-01-01

    Human respiratory syncytial virus (HRSV) is an important cause of severe respiratory tract disease in immunocompromised patients. Animal models are indispensable for evaluating novel intervention strategies in this complex patient population. To complement existing models in rodents and non-human primates, we have evaluated the potential benefits of an HRSV infection model in ferrets (Mustela putorius furo). Nine- to 12-month-old HRSV-seronegative immunocompetent or immunocompromised ferrets were infected with a low-passage wild-type strain of HRSV subgroup A (105 TCID50) administered by intra-tracheal or intra-nasal inoculation. Immune suppression was achieved by bi-daily oral administration of tacrolimus, mycophenolate mofetil, and prednisolone. Throat and nose swabs were collected daily and animals were euthanized four, seven, or 21 days post-infection (DPI). Virus loads were determined by quantitative virus culture and qPCR. We observed efficient HRSV replication in both the upper and lower respiratory tract. In immunocompromised ferrets, virus loads reached higher levels and showed delayed clearance as compared to those in immunocompetent animals. Histopathological evaluation of animals euthanized 4 DPI demonstrated that the virus replicated in the respiratory epithelial cells of the trachea, bronchi, and bronchioles. These animal models can contribute to an assessment of the efficacy and safety of novel HRSV intervention strategies. PMID:27314379

  17. SARS: systematic review of treatment effects.

    OpenAIRE

    Stockman, Lauren J.; Richard Bellamy; Paul Garner

    2006-01-01

    Editors' Summary Background. Severe acute respiratory syndrome (SARS) is caused by a virus; the main symptoms are pneumonia and fever. The virus is usually passed on when people sneeze or cough. SARS became a much-talked about disease in 2003, when over 8,000 cases and 774 deaths occurred worldwide. The situation was alarming, because the first-ever cases had only just appeared in 2002, in China, so the best way to treat this new disease was unknown. Not many drugs are effective against virus...

  18. "ISA-Lation" of Single-Stranded Positive-Sense RNA Viruses from Non-Infectious Clinical/Animal Samples.

    Directory of Open Access Journals (Sweden)

    Fabien Aubry

    Full Text Available Isolation of viral pathogens from clinical and/or animal samples has traditionally relied on either cell cultures or laboratory animal model systems. However, virus viability is notoriously susceptible to adverse conditions that may include inappropriate procedures for sample collection, storage temperature, support media and transportation. Using our recently described ISA method, we have developed a novel procedure to isolate infectious single-stranded positive-sense RNA viruses from clinical or animal samples. This approach, that we have now called "ISA-lation", exploits the capacity of viral cDNA subgenomic fragments to re-assemble and produce infectious viral RNA in susceptible cells. Here, it was successfully used to rescue enterovirus, Chikungunya and Tick-borne encephalitis viruses from a variety of inactivated animal and human samples. ISA-lation represents an effective option to rescue infectious virus from clinical and/or animal samples that may have deteriorated during the collection and storage period, but also potentially overcomes logistic and administrative difficulties generated when complying with current health and safety and biosecurity guidelines associated with shipment of infectious viral material.

  19. Animals Models of Human T Cell Leukemia Virus Type I Leukemogenesis.

    Science.gov (United States)

    Niewiesk, Stefan

    2016-03-31

    Infection with human T cell leukemia virus type I (HTLV-I) causes adult T cell leukemia (ATL) in a minority of infected individuals after long periods of viral persistence. The various stages of HTLV-I infection and leukemia development are studied by using several different animal models: (1) the rabbit (and mouse) model of persistent HTLV-I infection, (2) transgenic mice to model tumorigenesis by HTLV-I specific protein expression, (3) ATL cell transfers into immune-deficient mice, and (4) infection of humanized mice with HTLV-I. After infection, virus replicates without clinical disease in rabbits and to a lesser extent in mice. Transgenic expression of both the transactivator protein (Tax) and the HTLV-I bZIP factor (HBZ) protein have provided insight into factors important in leukemia/lymphoma development. To investigate factors relating to tumor spread and tissue invasion, a number of immune-deficient mice based on the severe combined immunodeficiency (SCID) or non-obese diabetic/SCID background have been used. Inoculation of adult T cell leukemia cell (lines) leads to lymphoma with osteolytic bone lesions and to a lesser degree to leukemia development. These mice have been used extensively for the testing of anticancer drugs and virotherapy. A recent development is the use of so-called humanized mice, which, upon transfer of CD34(+)human umbilical cord stem cells, generate human lymphocytes. Infection with HTLV-I leads to leukemia/lymphoma development, thus providing an opportunity to investigate disease development with the aid of molecularly cloned viruses. However, further improvements of this mouse model, particularly in respect to the development of adaptive immune responses, are necessary. PMID:27034390

  20. Animals

    International Nuclear Information System (INIS)

    The radionuclides of most concern with respect to contamination of animals after a nuclear accident are radioiodine, radiocaesium and radiostrontium (ICRP 30, 1979). Of the other significant anthropogenic radionuclides likely to be released in most accidents, only small proportions of that ingested will be absorbed in an animals gut, and the main animal products, milk and meat, will not normally be contaminated to a significant extent. Animal products will mostly be contaminated as a result of ingestion of contaminated feed and possibly, but to a much lesser extent, from inhalation (for radioiodine only). Direct external contamination of animals is of little or no consequence in human food production. Radioiodine and radiostrontium are important with respect to contamination of milk; radiocaesium contaminates both milk and meat. The physical and chemical form of a radionuclide can influence its absorption in the animal gut. For example, following the Chernobyl accident radiocaesium incorporated into vegetation by root uptake was more readily absorbed than that associated with the original deposit. The transfer of radiocaesium and radiostrontium to animals will be presented both as transfer coefficients and aggregated transfer coefficients. For most animal meat products, only radiocaesium is important as other radionuclides do not significantly contaminate muscle. Farm animal products are the most important foodstuff determining radiocaesium intake by the average consumer in the Nordic countries. The major potential source of radioiodine and radiostrontium to humans is milk and milk products. Of the different species, the smaller animals have the highest transfer of radiocaesium from fodder to meat and milk. (EG)

  1. Molecular phylogeny of coronaviruses including human SARS-CoV

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Phylogenetic tree of coronaviruses (CoVs) including the human SARS-associated virus is reconstructed from complete genomes by using our newly developed K- string composition approach. The relation of the human SARS-CoV to other coronaviruses, i.e. the rooting of the tree is suggested by choosing an appropriate outgroup. SARS-CoV makes a separate group closer but still distant from G2 (CoVs in mammalian host). The relation between different isolates of the human SARS virus is inferred by first constructing an ultrametric distance matrix from counting sequence variations in the genomes. The resulting tree is consistent with clinic relations between the SARS-CoV isolates. In addition to a larger variety of coronavirus genomes these results provide phylogenetic knowledge based on independent novel methodology as compared to recent phylogenetic studies on SARS-CoV.

  2. Antiviral activity of the Lippia graveolens (Mexican oregano essential oil and its main compound carvacrol against human and animal viruses

    Directory of Open Access Journals (Sweden)

    Marciele Ribas Pilau

    2011-12-01

    Full Text Available Mexican oregano (Lippia graveolens is a plant found in Mexico and Central America that is traditionally used as a medicinal herb. In the present study, we investigated the antiviral activity of the essential oil of Mexican oregano and its major component, carvacrol, against different human and animal viruses. The MTT test (3-4,5-dimethythiazol-2yl-2,5-diphenyl tetrazolium bromide was conducted to determine the selectivity index (SI of the essential oil, which was equal to 13.1, 7.4, 10.8, 9.7, and 7.2 for acyclovir-resistant herpes simplex virus type 1 (ACVR-HHV-1, acyclovir-sensitive HHV-1, human respiratory syncytial virus (HRSV, bovine herpesvirus type 2 (BoHV-2, and bovine viral diarrhoea virus (BVDV, respectively. The human rotavirus (RV and BoHV-1 and 5 were not inhibited by the essential oil. Carvacrol alone exhibited high antiviral activity against RV with a SI of 33, but it was less efficient than the oil for the other viruses. Thus, Mexican oregano oil and its main component, carvacrol, are able to inhibit different human and animal viruses in vitro. Specifically, the antiviral effects of Mexican oregano oil on ACVR-HHV-1 and HRSV and of carvacrol on RV justify more detailed studies.

  3. Animals

    Energy Technology Data Exchange (ETDEWEB)

    Skuterud, L.; Strand, P. [Norwegian Radiation Protection Authority (Norway); Howard, B.J. [Inst. of Terrestrial Ecology (United Kingdom)

    1997-10-01

    The radionuclides of most concern with respect to contamination of animals after a nuclear accident are radioiodine, radiocaesium and radiostrontium (ICRP 30, 1979). Of the other significant anthropogenic radionuclides likely to be released in most accidents, only small proportions of that ingested will be absorbed in an animals gut, and the main animal products, milk and meat, will not normally be contaminated to a significant extent. Animal products will mostly be contaminated as a result of ingestion of contaminated feed and possibly, but to a much lesser extent, from inhalation (for radioiodine only). Direct external contamination of animals is of little or no consequence in human food production. Radioiodine and radiostrontium are important with respect to contamination of milk; radiocaesium contaminates both milk and meat. The physical and chemical form of a radionuclide can influence its absorption in the animal gut. For example, following the Chernobyl accident radiocaesium incorporated into vegetation by root uptake was more readily absorbed than that associated with the original deposit. The transfer of radiocaesium and radiostrontium to animals will be presented both as transfer coefficients and aggregated transfer coefficients. For most animal meat products, only radiocaesium is important as other radionuclides do not significantly contaminate muscle. Farm animal products are the most important foodstuff determining radiocaesium intake by the average consumer in the Nordic countries. The major potential source of radioiodine and radiostrontium to humans is milk and milk products. Of the different species, the smaller animals have the highest transfer of radiocaesium from fodder to meat and milk. (EG). 68 refs.

  4. The use of non-human primates as animal models for the study of hepatitis viruses

    OpenAIRE

    C.L. Vitral; C.F.T. Yoshida; A.M.C. Gaspar

    1998-01-01

    Hepatitis viruses belong to different families and have in common a striking hepatotropism and restrictions for propagation in cell culture. The transmissibility of hepatitis is in great part limited to non-human primates. Enterically transmitted hepatitis viruses (hepatitis A virus and hepatitis E virus) can induce hepatitis in a number of Old World and New World monkey species, while the host range of non-human primates susceptible to hepatitis viruses transmitted by the parenteral route (h...

  5. Circular replication-associated protein encoding DNA viruses identified in the faecal matter of various animals in New Zealand.

    Science.gov (United States)

    Steel, Olivia; Kraberger, Simona; Sikorski, Alyssa; Young, Laura M; Catchpole, Ryan J; Stevens, Aaron J; Ladley, Jenny J; Coray, Dorien S; Stainton, Daisy; Dayaram, Anisha; Julian, Laurel; van Bysterveldt, Katherine; Varsani, Arvind

    2016-09-01

    In recent years, innovations in molecular techniques and sequencing technologies have resulted in a rapid expansion in the number of known viral sequences, in particular those with circular replication-associated protein (Rep)-encoding single-stranded (CRESS) DNA genomes. CRESS DNA viruses are present in the virome of many ecosystems and are known to infect a wide range of organisms. A large number of the recently identified CRESS DNA viruses cannot be classified into any known viral families, indicating that the current view of CRESS DNA viral sequence space is greatly underestimated. Animal faecal matter has proven to be a particularly useful source for sampling CRESS DNA viruses in an ecosystem, as it is cost-effective and non-invasive. In this study a viral metagenomic approach was used to explore the diversity of CRESS DNA viruses present in the faeces of domesticated and wild animals in New Zealand. Thirty-eight complete CRESS DNA viral genomes and two circular molecules (that may be defective molecules or single components of multicomponent genomes) were identified from forty-nine individual animal faecal samples. Based on shared genome organisations and sequence similarities, eighteen of the isolates were classified as gemycircularviruses and twelve isolates were classified as smacoviruses. The remaining eight isolates lack significant sequence similarity with any members of known CRESS DNA virus groups. This research adds significantly to our knowledge of CRESS DNA viral diversity in New Zealand, emphasising the prevalence of CRESS DNA viruses in nature, and reinforcing the suggestion that a large proportion of CRESS DNA viruses are yet to be identified. PMID:27211884

  6. Immunogenicity and protective efficacy of recombinant major envelope protein (rH3L) of buffalopox virus in animal models.

    Science.gov (United States)

    Kumar, Amit; Yogisharadhya, Revanaiah; Venkatesan, Gnanavel; Bhanuprakash, Veerakyathappa; Shivachandra, Sathish Bhadravati

    2016-02-01

    Buffalopox virus, a zoonotic Indian vaccinia-like virus, is responsible for contagious disease affecting mainly buffaloes, cattle and humans. H3L gene, encoding for an immunodominant major envelope protein of intracellular mature virion of orthopoxviruses, is highly conserved and found to elicit neutralizing antibodies. Therefore in the present study, the immunogenicity and protective efficacy of the recombinant H3L protein of buffalopox virus in laboratory animal models has been evaluated. A partial H3L gene encoding for the C-terminal truncated ectodomain of H3L protein (1M to I280) of BPXV-Vij/96 strain was cloned, over-expressed and purified as histidine-tagged fusion protein (50 kDa) from Escherichia coli using Ni-NTA affinity chromatography. The purified rH3L protein was further used for active immunization of guinea pig (250 μg/dose) and adult mice (10 μg and 50 μg/dose) with or without adjuvants (alum, Freund's Complete Adjuvant and CpG). Subsequently, a gradual increase in antigen specific serum IgG as well as neutralizing antibody titres measured by using indirect-ELISA and serum neutralization test respectively, was noted in both guinea pigs and mouse models. Suckling mice immunized passively with anti-H3L serum showed 80% pre-exposure prophylaxis upon challenge with virulent buffalopox virus strain. An indirect-ELISA based on rH3L protein showed no cross-reactivity with hyperimmune sera against sheeppox virus (SPPV), goatpox virus (GTPV), orf virus (ORFV), foot- and- mouth disease virus (FMDV), peste des petits ruminants virus (PPRV) and bluetongue virus (BTV) during the course of study. The study highlights the potential utility of rH3L protein as a safer prophylactic and diagnostic reagent for buffalopox. PMID:26723250

  7. Stability of SARS Coronavirus in Human Specimens and Environment and Its Sensitivity to Heating and UV Irradiation

    Institute of Scientific and Technical Information of China (English)

    SHU-MING DUAN; XIAO-PING DONG; SARS RESEARCH TEAM; XIN-SHENG ZHAO; RUI-FU WEN; JING-JING HUANG; GUO-HUA PI; SU-XIANG ZHANG; JUN HAN; SHENG-LI BI; LI RUAN

    2003-01-01

    The causal agent for SARS is considered as a novel coronavirus that has never been described both in human and animals previously. The stability of SARS coronavirus in human specimens and in environments was studied. Methods Using a SARS coronavirus strain CoV-P9,which was isolated from pharyngeal swab of a probable SARS case in Beijing, its stability in mimic human specimens and in mimic environment including surfaces of commonly used materials or in household conditions, as well as its resistances to temperature and UV irradiation were analyzed. A total of 106 TCID50 viruses were placed in each tested condition, and changes of the viral infectivity in samples after treatments were measured by evaluating cytopathic effect (CPE) in cell line Vero-E6 at 48 h after infectionn. Results The results showed that SARS coronavirus in the testing condition could survive in serum, 1:20 diluted sputum and feces for at least 96 h, whereas it could remain alive in urine for at least 72 h with a low level of infectivity. The survival abilities on the surfaces of eight different materials and in water were quite comparable, revealing reduction of infectivity after 72 to 96 h exposure. Viruses stayed stable at 4℃, at room temperature (20℃) and at 37℃ for at least 2 h without remarkable change in the infectious ability in cells, but were convened to be non-infectious after 90-, 60- and 30-min exposure at 56℃, at 67℃ and at 75℃, respectively. Irradiation of UV for 60 min on the virus in culture medium resulted in the destruction of viral infectivity at an undetectable level. Conclusion The survival ability of SARS coronavirus in human specimens and in environments seems to be relatively strong. Heating and UV irradiation can efficiently eliminate the viral infectivity.

  8. Wetland InSAR

    Science.gov (United States)

    Wdowinski, S.; Kim, S.; Amelung, F.; Dixon, T.

    2006-12-01

    Wetlands are transition zones where the flow of water, the nutrient cycling, and the sun energy meet to produce a unique and very productive ecosystem. They provide critical habitat for a wide variety of plant and animal species, including the larval stages of many ocean fish. Wetlands also have a valuable economical importance, as they filter nutrients and pollutants from fresh water used by human and provide aquatic habitats for outdoor recreation, tourism, and fishing. Globally, many such regions are under severe environmental stress, mainly from urban development, pollution, and rising sea level. However, there is increasing recognition of the importance of these habitats, and mitigation and restoration activities have begun in a few regions. A key element in wetlands conservation, management, and restoration involves monitoring its hydrologic system, as the entire ecosystem depends on its water supply. Heretofore, hydrologic monitoring of wetlands are conducted by stage (water level) stations, which provide good temporal resolution, but suffer from poor spatial resolution, as stage station are typically distributed several, or even tens of kilometers, from one another. Wetland application of InSAR provides the needed high spatial resolution hydrological observations, complementing the high temporal resolution terrestrial observations. Although conventional wisdom suggests that interferometry does not work in vegetated areas, several studies have shown that both L- and C-band interferograms with short acquisition intervals (1-105 days) can maintain excellent coherence over wetlands. In this study we explore the usage of InSAR for detecting water level changes in various wetland environments around the world, including the Everglades (south Florida), Louisiana Coast (southern US), Chesapeake Bay (eastern US), Pantanal (Brazil), Okavango Delta (Botswana), and Lena Delta (Siberia). Our main study area is the Everglades wetland (south Florida), which is covered by

  9. The use of non-human primates as animal models for the study of hepatitis viruses

    Directory of Open Access Journals (Sweden)

    C.L. Vitral

    1998-08-01

    Full Text Available Hepatitis viruses belong to different families and have in common a striking hepatotropism and restrictions for propagation in cell culture. The transmissibility of hepatitis is in great part limited to non-human primates. Enterically transmitted hepatitis viruses (hepatitis A virus and hepatitis E virus can induce hepatitis in a number of Old World and New World monkey species, while the host range of non-human primates susceptible to hepatitis viruses transmitted by the parenteral route (hepatitis B virus, hepatitis C virus and hepatitis delta virus is restricted to few species of Old World monkeys, especially the chimpanzee. Experimental studies on non-human primates have provided an invaluable source of information regarding the biology and pathogenesis of these viruses, and represent a still indispensable tool for vaccine and drug testing.

  10. Effect of radiation on certain animal viruses in liquid swine manure

    Energy Technology Data Exchange (ETDEWEB)

    Simon, J.; Mocsari, E.; di Gleria, M.; Felkai, V. (Phylaxia Oltoanyag- es Tapszertermeloe Vallalat, Budapest (Hungary); Orszagos Allategeszseguegyi Intezet, Budapest (Hungary))

    1983-03-01

    The virucidal effect of /sup 60/Co gamma radiation was studied in cell culture medium and in liquid swine manure involving the most important porcine viruses that can be spread by liquid manure. The radiation doses (20 kGy and 30 kGy) were determined in preliminary experiments employing a porcine enterovirus from the serogroup 1 (Teschen group). In the main experiment, the following viruses were employed: swine vesicular disease (SVD) virus, type C foot-and-mouth disease (FMD) virus, a field strain of Aujeszky's disease (AD) virus, transmissible gastroenteritis (TGE) virus, as well as bovine viral diarrhea (BVD) virus. The latter strain served as a model for hog cholera virus. The results of the experiments indicate that safe disinfection of the virus infected liquid swine manure by ionizing radiation requires a radiation dose of 30 kGy.

  11. Effect of radiation on certain animal viruses in liquid swine manure

    International Nuclear Information System (INIS)

    The virucidal effect of 60Co gamma radiation was studied in cell culture medium and in liquid swine manure involving the most important porcine viruses that can be spread by liquid manure. The radiation doses (20 kGy and 30 kGy) were determined in preliminary experiments employing a porcine enterovirus from the serogroup 1 (Teschen group). In the main experiment, the following viruses were employed: swine vesicular disease (SVD) virus, type C foot-and-mouth disease (FMD) virus, a field strain of Aujeszky's disease (AD) virus, transmissible gastroenteritis (TGE) virus, as well as bovine viral diarrhoea (BVD) virus. The latter strain served as a model for hog cholera virus. The results of the experiments indicate that safe disinfection of the virus infected liquid swine manure by ionizing radiation requires a radiation dose of 30 kGy. (author)

  12. The woodchuck as an animal model for pathogenesis and therapy of chronic hepatitis B virus infection

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This review describes the woodchuck and the woodchuck hepatitis virus (WHV) as an animal model for pathogenesis and therapy of chronic hepatitis B virus (HBV) infection and disease in humans. The establishment of woodchuck breeding colonies, and use of laboratory-reared woodchucks infected with defined WHV inocula, have enhanced our understanding of the virology and immunology of HBV infection and disease pathogenesis, including major sequelae like chronic hepatitis and hepatocellular carcinoma. The role of persistent WHV infection and of viral load on the natural history of infection and disease progression has been firmly established along the way. More recently, the model has shed new light on the role of host immune responses in these natural processes,and on how the immune system of the chronic carrier can be manipulated therapeutically to reduce or delay serious disease sequelae through induction of the recovery phenotype. The woodchuck is an outbred species and is not well defined immunologically due to a limitation of available host markers. However, the recent development of several key host response assays for woodchucks provides experimental opportunities for further mechanistic studies of outcome predictors in neonatal- and adult-acquired infections. Understanding the virological and immunological mechanisms responsible for resolution of self-limited infection, and for the onset and maintenance of chronic infection, will greatly facilitate the development of successful strategies for the therapeutic eradication of established chronic HBV infection. Likewise, the results of drug efficacy and toxicity studies in the chronic carrier woodchucks are predictive for responses of patients chronically infected with HBV. Therefore, chronic WHV carrier woodchucks provide a well-characterized mammalian model for preclinical evaluation of the safety and efficacy of drug candidates, experimental therapeutic vaccines, and immunomodulators for the treatment and

  13. Removal of viruses and indicators by anaerobic membrane bioreactor treating animal waste.

    Science.gov (United States)

    Wong, Kelvin; Xagoraraki, Irene; Wallace, James; Bickert, William; Srinivasan, Sangeetha; Rose, Joan B

    2009-01-01

    Appropriate treatment of agricultural waste is necessary for the protection of public health in rural areas because land-applied animal manure may transmit zoonotic disease. In this study, we evaluated the potential of using a pilot anaerobic membrane bioreactor (AnMBR) to treat agricultural waste. The AnMBR system, following a conventional complete mix anaerobic digester (CMAD), achieved high removals of biological and chemical agents. The mean log(10) removals of Escherichia coli, enterococci, Clostridium perfringens, and coliphage by the AnMBR were 5.2, 6.1, 6.4, and 3.7, respectively, and for the CMAD were 1.5, 1.2, 0.1, and 0.5, respectively. Compared with other indicators, coliphage was observed most frequently and had the highest concentration in effluent samples. Bovine adenoviruses and bovine polymaviruses (BPyV) were monitored in this study using nested PCR methods. All of the CMAD influent and CMAD effluent samples were positive for both viruses, and three AnMBR effluent samples were BPyV positive. The mean removals of total Kjeldahl nitrogen, total phosphate, chemical oxygen demand, total solids, and volatile solids by the entire system were 31, 96, 92, 82, and 91%, respectively, but there was no removal of ammonium. When the AnMBR was operated independent of the CMAD, AnMBR achieved similar E. coli and enterococci removals as the combined CMAD/AnMBR system. The high quality of effluent produced by the pilot AnMBR system in this study demonstrated that such systems can be considered as alternatives for managing animal manure. PMID:19549946

  14. The outbreak pattern of the SARS cases in Asia

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhibin; SHENG Chengfa; MA Zufei; LI Dianmo

    2004-01-01

    The severe acute respiratory syndrome (SARS) caused tremendous damage to many Asia countries, especially China. The transmission process and outbreak pattern of SARS is still not well understood. This study aims to find a simple model to describe the outbreak pattern of SARS cases by using SARS case data commonly released by governments. The outbreak pattern of cumulative SARS cases is expected to be a logistic type because the infection will be slowed down due to the increasing control effort by people and/or due to depletion of susceptible individuals. The increase rate of SARS cases is expected to decrease with the cumulative SARS cases, as described by the traditional logistical model, which is widely used in population dynamic studies. The instantaneous rate of increases were significantly and negatively correlated with the cumulative SARS cases in mainland of China (including Beijing, Hebei, Tianjin, Shanxi, the Autonomous Region of Inner Mongolia) and Singapore. The basic reproduction number R0 in Asia ranged from 2.0 to 5.6 (except for Taiwan, China). The R0 of Hebei and Tianjinwere much higher than that of Singapore, Hongkong, Beijing, Shanxi, Inner Mongolia, indicating SARS virus might have originated differently or new mutations occurred during transmission. We demonstrated that the outbreaks of SARS in many regions of Asia were well described by the logistic model, and the control measures implemented by governments are effective. The maximum instantaneous rate of increase, basic reproductive number, and maximum cumulative SARS cases were also calculated by using the logistic model.

  15. Detection of spring viraemia of carp virus in imported amphibians reveals an unanticipated foreign animal disease threat.

    Science.gov (United States)

    Ip, Hon S; Lorch, Jeffrey M; Blehert, David S

    2016-01-01

    Global translocation of plants and animals is a well-recognized mechanism for introduction of pathogens into new regions. To mitigate this risk, various tools such as preshipment health certificates, quarantines, screening for specific disease agents and outright bans have been implemented. However, such measures only target known infectious agents and their hosts and may fail to prevent translocation of even well-recognized pathogens if they are carried by novel host species. In a recent example, we screened an imported shipment of Chinese firebelly newts (Cynops orientalis) for Batrachochytrium salamandrivorans, an emergent fungal pathogen of salamanders. All animals tested negative for the fungus. However, a virus was cultured from internal organs from 7 of the 11 individual dead salamanders and from two pools of tissues from four additional dead animals. Sequencing of a portion of the glycoprotein gene from all viral isolates indicated 100% identity and that they were most closely related to spring viraemia of carp virus (SVCV). Subsequently, SVCV-specific PCR testing indicated the presence of virus in internal organs from each of the four animals previously pooled, and whole-genome sequencing of one of the viral isolates confirmed genomic arrangement characteristic of SVCV. SVCV is a rhabdovirus pathogen of cyprinid fish that is listed as notifiable to the Office International des Epizooties. This discovery reveals a novel route for potential spillover of this economically important pathogen as rhabdovirus has not previously been documented in amphibians. PMID:27599472

  16. Detection of spring viraemia of carp virus in imported amphibians reveals an unanticipated foreign animal disease threat.

    Science.gov (United States)

    Ip, Hon S; Lorch, Jeffrey M; Blehert, David S

    2016-09-07

    Global translocation of plants and animals is a well-recognized mechanism for introduction of pathogens into new regions. To mitigate this risk, various tools such as preshipment health certificates, quarantines, screening for specific disease agents and outright bans have been implemented. However, such measures only target known infectious agents and their hosts and may fail to prevent translocation of even well-recognized pathogens if they are carried by novel host species. In a recent example, we screened an imported shipment of Chinese firebelly newts (Cynops orientalis) for Batrachochytrium salamandrivorans, an emergent fungal pathogen of salamanders. All animals tested negative for the fungus. However, a virus was cultured from internal organs from 7 of the 11 individual dead salamanders and from two pools of tissues from four additional dead animals. Sequencing of a portion of the glycoprotein gene from all viral isolates indicated 100% identity and that they were most closely related to spring viraemia of carp virus (SVCV). Subsequently, SVCV-specific PCR testing indicated the presence of virus in internal organs from each of the four animals previously pooled, and whole-genome sequencing of one of the viral isolates confirmed genomic arrangement characteristic of SVCV. SVCV is a rhabdovirus pathogen of cyprinid fish that is listed as notifiable to the Office International des Epizooties. This discovery reveals a novel route for potential spillover of this economically important pathogen as rhabdovirus has not previously been documented in amphibians.

  17. Detection of spring viraemia of carp virus in imported amphibians reveals an unanticipated foreign animal disease threat

    Science.gov (United States)

    Ip, Hon S.; Lorch, Jeffrey M.; Blehert, David

    2016-01-01

    Global translocation of plants and animals is a well-recognized mechanism for introduction of pathogens into new regions. To mitigate this risk, various tools such as preshipment health certificates, quarantines, screening for specific disease agents and outright bans have been implemented. However, such measures only target known infectious agents and their hosts and may fail to prevent translocation of even well-recognized pathogens if they are carried by novel host species. In a recent example, we screened an imported shipment of Chinese firebelly newts (Cynops orientalis) for Batrachochytrium salamandrivorans, an emergent fungal pathogen of salamanders. All animals tested negative for the fungus. However, a virus was cultured from internal organs from 7 of the 11 individual dead salamanders and from two pools of tissues from four additional dead animals. Sequencing of a portion of the glycoprotein gene from all viral isolates indicated 100% identity and that they were most closely related to spring viraemia of carp virus (SVCV). Subsequently, SVCV-specific PCR testing indicated the presence of virus in internal organs from each of the four animals previously pooled, and whole-genome sequencing of one of the viral isolates confirmed genomic arrangement characteristic of SVCV. SVCV is a rhabdovirus pathogen of cyprinid fish that is listed as notifiable to the Office International des Epizooties. This discovery reveals a novel route for potential spillover of this economically important pathogen as rhabdovirus has not previously been documented in amphibians.

  18. Animals

    Institute of Scientific and Technical Information of China (English)

    杨光

    2000-01-01

    The largest animal ever to live on the earth is the blue whale(蓝鲸)It weighs about 80 tons--more than 24 elephants. It is more than 30 metres long. A newborn baby whale weighs as much as a big elephant.

  19. ANIMALS

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Mammals(哺乳动物)Mammals are the world's most dominant(最占优势的)animal.They are extremely(非常)diverse(多种多样的)creatures(生物,动物)that include(包括)the biggest ever animal (the blue whale鲸,which eats up to 6 tons every day),the smallest(leaf-nosed bat小蹄蝠) and the laziest(sloth树獭,who spends 80% of their time sleeping).There are over 4,600 kinds of mammals and they live in very different environments(环境)—oceans(海洋),rivers,the jungle(丛林),deserts,and plains(平原).

  20. Detection and genetic characterization of foot‐and‐mouth disease viruses in samples from clinically healthy animals in endemic settings

    DEFF Research Database (Denmark)

    Jamal, Syed Muhammad; Ferrari, G.; Hussain, M.;

    2012-01-01

    in Pakistan (n = 245), one (of three) live animal market in Afghanistan (n = 61) and both the live animal markets in Tajikistan (n = 120) all tested negative. However, 2 of 129 (∼2%) samples from Gondal and 11 of 123 (9%) from Chichawatni markets in Pakistan were positive for FMDV RNA. Similarly, 12 of 81 (15......A total of 1501 oral swab samples from Pakistan, Afghanistan and Tajikistan were collected from clinically healthy animals between July 2008 and August 2009 and assayed for the presence of foot‐and‐mouth disease virus (FMDV) RNA. The oral swab samples from two (of four) live animal markets......%) samples from Kabul and 10 of 20 (50%) from Badakhshan in Afghanistan were found to be positive. Serotypes A and O of FMDV were identified within these samples. Oral swab samples were also collected from dairy colonies in Harbanspura, Lahore (n = 232) and Nagori, Karachi (n = 136), but all tested negative...

  1. Tick-borne encephalitis virus (TBEV) – findings on cross reactivity and longevity of TBEV antibodies in animal sera

    OpenAIRE

    Klaus, Christine; Ziegler, Ute; Kalthoff, Donata; Hoffmann, Bernd; Beer, Martin

    2014-01-01

    Background By using animal sera as sentinels, natural TBEV foci could be identified and further analyses including investigations of ticks could be initiated. However, antibody response against TBEV-related flaviviruses might adversely affect the readout of such a monitoring. Therefore, the cross-reactivity of the applied TBEV serology test systems – enzyme linked immunosorbent assay (ELISA) and virus neutralization test (VNT) – as well as the longevity of TBEV antibody titres in sheep and go...

  2. Detection of Breda virus antigen and antibody in humans and animals by enzyme immunoassay.

    OpenAIRE

    Brown, D W; Beards, G M; Flewett, T. H.

    1987-01-01

    Enzyme immunoassays were developed for the detection of Breda virus antibody and antigen. Cattle sera collected in the United Kingdom were found to have a high prevalence of antibody (55%) to Breda virus when examined in a competitive enzyme-linked immunosorbent assay. A low prevalence of antibody was found in pigs (2.2%), and no antibody was found in sheep or goat sera. No antibody to either Breda virus or Berne virus was detected in human sera collected from veterinarians and farm workers. ...

  3. Recoding structural glycoprotein E2 in classical swine fever virus (CSFV) produces complete virus attenuation in swine and protects infected animals against disease.

    Science.gov (United States)

    Velazquez-Salinas, Lauro; Risatti, Guillermo R; Holinka, Lauren G; O'Donnell, Vivian; Carlson, Jolene; Alfano, Marialexia; Rodriguez, Luis L; Carrillo, Consuelo; Gladue, Douglas P; Borca, Manuel V

    2016-07-01

    Controlling classical swine fever (CSF) mainly involves vaccination with live attenuated vaccines (LAV). Experimental CSFV LAVs has been lately developed through reverse genetics using several different approaches. Here we present that codon de-optimization in the major CSFV structural glycoprotein E2 coding region, causes virus attenuation in swine. Four different mutated constructs (pCSFm1-pCSFm4) were designed using various mutational approaches based on the genetic background of the highly virulent strain Brescia (BICv). Three of these constructs produced infectious viruses (CSFm2v, CSFm3v, and CSFm4v). Animals infected with CSFm2v presented a reduced and extended viremia but did not display any CSF-related clinical signs. Animals that were infected with CSFm2v were protected against challenge with virulent parental BICv. This is the first report describing the development of an attenuated CSFV experimental vaccine by codon usage de-optimization, and one of the few examples of virus attenuation using this methodology that is assessed in a natural host. PMID:27110709

  4. Antiviral drug discovery against SARS-CoV.

    Science.gov (United States)

    Wu, Yu-Shan; Lin, Wen-Hsing; Hsu, John T-A; Hsieh, Hsing-Pang

    2006-01-01

    Severe Acute Respiratory Syndrome (SARS) is a life-threatening infectious disease caused by SARS-CoV. In the 2003 outbreak, it infected more than 8,000 people worldwide and claimed the lives of more than 900 victims. The high mortality rate resulted, at least in part, from the absence of definitive treatment protocols or therapeutic agents. Although the virus spreading has been contained, due preparedness and planning, including the successful development of antiviral drugs against SARS-CoV, is necessary for possible reappearance of SARS. In this review, we have discussed currently available strategies for antiviral drug discovery and how these technologies have been utilized to identify potential antiviral agents for the inhibition of SARS-CoV replication. Moreover, progress in the drug development based on different molecular targets is also summarized, including 1) Compounds that block the S protein-ACE2-mediated viral entry; 2) Compounds targeting SARS-CoV M(pro); 3) Compounds targeting papain-like protease 2 (PLP2); 4) Compounds targeting SARS-CoV RdRp; 5) Compounds targeting SARS-CoV helicase; 6) Active compounds with unspecified targets; and 7) Research on siRNA. This review aims to provide a comprehensive account of drug discovery on SARS. The experiences with the SARS outbreak and drug discovery would certainly be an important lesson for the drug development for any new viral outbreaks that may emerge in the future.

  5. Keynote presentation : SAR systems

    NARCIS (Netherlands)

    Halsema, D. van; Otten, M.P.G.; Maas, A.P.M.; Bolt, R.J.; Anitori, L.

    2011-01-01

    Synthetic Aperture Radar (SAR) systems are becoming increasingly important sensors in as well the military environment as in the civilian market. In this keynote presentation an overview will be given over more than 2 decades of SAR system∼ and SAR application development at TNO in the Netherlands.

  6. The SARS-coronavirus-host interactome: identification of cyclophilins as target for pan-coronavirus inhibitors.

    Directory of Open Access Journals (Sweden)

    Susanne Pfefferle

    2011-10-01

    Full Text Available Coronaviruses (CoVs are important human and animal pathogens that induce fatal respiratory, gastrointestinal and neurological disease. The outbreak of the severe acute respiratory syndrome (SARS in 2002/2003 has demonstrated human vulnerability to (Coronavirus CoV epidemics. Neither vaccines nor therapeutics are available against human and animal CoVs. Knowledge of host cell proteins that take part in pivotal virus-host interactions could define broad-spectrum antiviral targets. In this study, we used a systems biology approach employing a genome-wide yeast-two hybrid interaction screen to identify immunopilins (PPIA, PPIB, PPIH, PPIG, FKBP1A, FKBP1B as interaction partners of the CoV non-structural protein 1 (Nsp1. These molecules modulate the Calcineurin/NFAT pathway that plays an important role in immune cell activation. Overexpression of NSP1 and infection with live SARS-CoV strongly increased signalling through the Calcineurin/NFAT pathway and enhanced the induction of interleukin 2, compatible with late-stage immunopathogenicity and long-term cytokine dysregulation as observed in severe SARS cases. Conversely, inhibition of cyclophilins by cyclosporine A (CspA blocked the replication of CoVs of all genera, including SARS-CoV, human CoV-229E and -NL-63, feline CoV, as well as avian infectious bronchitis virus. Non-immunosuppressive derivatives of CspA might serve as broad-range CoV inhibitors applicable against emerging CoVs as well as ubiquitous pathogens of humans and livestock.

  7. Chimeric hepatitis B virus (HBV)/hepatitis C virus (HCV) subviral envelope particles induce efficient anti-HCV antibody production in animals pre-immunized with HBV vaccine.

    Science.gov (United States)

    Beaumont, Elodie; Roingeard, Philippe

    2015-02-18

    The development of an effective, affordable prophylactic vaccine against hepatitis C virus (HCV) remains a medical priority. The recently described chimeric HBV-HCV subviral envelope particles could potentially be used for this purpose, as they could be produced by industrial procedures adapted from those established for the hepatitis B virus (HBV) vaccine. We show here, in an animal model, that pre-existing immunity acquired through HBV vaccination does not influence the immunogenicity of the HCV E2 protein presented by these chimeric particles. Thus, these chimeric HBV-HCV subviral envelope particles could potentially be used as a booster in individuals previously vaccinated against HBV, to induce protective immunity to HCV. PMID:25596457

  8. Radiation Inactivation of Foot-and-Mouth Disease Virus in the Blood, Lymphatic Glands and Bone Marrow of the Carcasses of Infected Animals

    International Nuclear Information System (INIS)

    The FMD virus, like RP, SF and ASF viruses, is disseminated by infected animal products. The effects of gamma radiation on FMD virus cultures in vitro have been studied. According to these results, a dose of 3 Mrad when the virus is in the liquid state, and of 4 Mrad when it is in the dry state, is necessary to reduce the number of virus particles from 107 to 1. The D10 value for the liquid FMD virus is equivalent to 481 krad± the D10 value for the dried virus is equivalent to 626 krad. The effects of gamma radiation on FMD virus in situ have been studied. According to these results, to inactivate the FMD virus in the experimentally-infected pigs' tissues where the viral contents are the highest (blood, bone marrow, lymphatic glands), doses of 2 Mrad for the blood and bone marrow and of 1.5 Mrad for the lymphatic glands are necessary. Radiation may offer a possible means of reducing or eliminating the virus titre in many infected animal products and solve consequent quarantine problems. (author)

  9. Quantification of Human and Animal Viruses to Differentiate the Origin of the Fecal Contamination Present in Environmental Samples

    Directory of Open Access Journals (Sweden)

    Sílvia Bofill-Mas

    2013-01-01

    Full Text Available Many different viruses are excreted by humans and animals and are frequently detected in fecal contaminated waters causing public health concerns. Classical bacterial indicator such as E. coli and enterococci could fail to predict the risk for waterborne pathogens such as viruses. Moreover, the presence and levels of bacterial indicators do not always correlate with the presence and concentration of viruses, especially when these indicators are present in low concentrations. Our research group has proposed new viral indicators and methodologies for determining the presence of fecal pollution in environmental samples as well as for tracing the origin of this fecal contamination (microbial source tracking. In this paper, we examine to what extent have these indicators been applied by the scientific community. Recently, quantitative assays for quantification of poultry and ovine viruses have also been described. Overall, quantification by qPCR of human adenoviruses and human polyomavirus JC, porcine adenoviruses, bovine polyomaviruses, chicken/turkey parvoviruses, and ovine polyomaviruses is suggested as a toolbox for the identification of human, porcine, bovine, poultry, and ovine fecal pollution in environmental samples.

  10. Identification of synthetic vaccine candidates against SARS CoV infection

    International Nuclear Information System (INIS)

    Three peptides, D1 (amino acid residues 175-201), D2 (a.a. 434-467), and TM (a.a. 1128-1159), corresponding to the spike protein (S) of severe acute respiratory syndrome corona virus (SARS CoV) were synthesized and their immunological functions were investigated in three different animals models (mice, guinea pigs, and rabbits). The peptides mixture formulated either with Freund's adjuvant or synthetic adjuvant Montanide ISA-51/oligodeoxy nucleotide CpG (ISA/CpG) could elicit antisera in immunized animals which were capable of inhibiting SARS/HIV pseudovirus entry into HepG2 cells. The neutralizing epitopes were identified using peptides to block the neutralizing effect of guinea pig antisera. The major neutralizing epitope was located on the D2 peptide, and the amino acid residue was fine mapped to 434-453. In BALB/c mice T-cell proliferation assay revealed that only D2 peptide contained T-cell epitope, the sequence of which corresponded to amino acid residue 434-448. The ISA/CpG formulation generated anti-D2 IgG titer comparable to those obtained from Freund's adjuvant formulation, but generated fewer antibodies against D1 or TM peptides. The highly immunogenic D2 peptide contains both neutralizing and Th cell epitopes. These results suggest that synthetic peptide D2 would be useful as a component of SARS vaccine candidates

  11. Differentiation of FMD infected animals from vaccinated animals by the use of non-structural proteins of foot and mouth disease virus in Myanmar

    International Nuclear Information System (INIS)

    Four non-structural proteins (NSP) foot and mouth disease virus (FMDV) ELISA kits were received through the FAO/IAEA Coordinated Research Project (CRP). From 1999-2004, 10 States and Divisions out of 14 in Myanmar were visited by the staff of National FMD Laboratory and a total of 4704 sera from cattle, buffaloes, goats and pigs were collected. Sera were investigated for FMD serotype prevalence using the Liquid Phase Blocking ELISA (LPBE) and then any positive sera in this system were tested to differentiate infected animals from vaccinated by using four commercial FMDV NSP ELISA kits. The negative and positive results were evaluated to compare the sensitivity and the specificity of various FMDV NSP ELISA kits. (author)

  12. SARS Immunity and Vaccination

    Institute of Scientific and Technical Information of China (English)

    Minsheng Zhu

    2004-01-01

    Severe acute respiratory syndrome (SARS) is a serious and fatal infectious disease caused by SARS coronavirus (SARS-Cov), a novel human coronavirus. SARS-Cov infection stimulates cytokines (e.g., IL-10,IFN-γ, IL-1, etc.) expression dramatically, and T lymphocytes and their subsets CD4+ and CD8+ T cells are decreased after onset of the disease. SARS-specific IgG antibody is generated in the second week and persists for a long time, whereas IgM is expressed transiently. The spike protein and neucleocapsid protein are most abundant in SARS-Cov and contribute dominantly to the antibody production during the course of disease. Spike protein, especially the ACE-2 binding region (318-510aa) is capable of producing neutralizing antibody to SARS-Cov. Neucleocapsid protein induces protective specific CTL to SARS-Cov. Therefore, applications with spike subunit, neucleocapsid subunit as well as inactivated SARS-Cov are three prospective vaccination strategies for SARS.

  13. SARS Immunity and Vaccination

    Institute of Scientific and Technical Information of China (English)

    MinshengZhu

    2004-01-01

    Severe acute respiratory syndrome (SARS) is a serious and fatal infectious disease caused by SARS coronavirus (SARS-Cov), a novel human coronavirus. SARS-Cov infection stimulates cytokines (e.g., IL-10,IFN-γ, IL-1, etc.) expression dramatically, and T lymphocytes and their subsets CD4+ and CD8+ T cells are decreased after onset of the disease. SARS-specific IgG antibody is generated in the second week and persists for a long time, whereas IgM is expressed transiently. The spike protein and neucleocapsid protein are most abundant in SARS-Cov and contribute dominantly to the antibody production during the course of disease.Spike protein, especially the ACE-2 binding region (318-510aa) is capable of producing neutralizing antibody to SARS-Cov. Neucleocapsid protein induces protective specific CTL to SARS-Cov. Therefore, applications with spike subunit, neucleocapsid subunit as well as inactivated SARS-Cov are three prospective vaccination strategies for SARS.

  14. Seroprevalence of Borrelia burgdorferi sensu lato and tick-borne encephalitis virus in zoo animal species in the Czech Republic.

    Science.gov (United States)

    Sirmarová, Jana; Tichá, Lucie; Golovchenko, Marina; Salát, Jiří; Grubhoffer, Libor; Rudenko, Nataliia; Nowotny, Norbert; Růžek, Daniel

    2014-09-01

    This study was conducted to evaluate the prevalence of antibodies against Borrelia bugdorferi (Bb) s.l. and tick-borne encephalitis virus (TBEV) in zoo animals in the Czech Republic. We collected 133 serum samples from 69 animal species from 5 zoos located in different parts of the country. The samples were obtained from even-toed ungulates (n=78; 42 species), odd-toed ungulates (n=32; 11 species), carnivores (n=13; 9 species), primates (n=2, 2 species), birds (n=3; 2 species), and reptiles (n=5; 3 species). A high antibody prevalence (60%) was observed for Bb s.l. On the other hand, only two animals had TBEV-specific antibodies: a markhor (Capra falconeri) and a reindeer (Rangifer tarandus), both from the same zoo, located in an area endemic for TBEV. Both of these animals were also positive for Bb s.l. antibodies. Our results indicate that a high number of animal species in the Czech zoos were exposed to Bb s.l. and that TBEV infection occurred at least in one of the investigated zoos. Considering the pathogenic potential of these two tick-borne pathogens, clinical and serological monitoring should be continued, and therapeutic and preventive measures should be taken when necessary.

  15. Molecular analyses detect natural coinfection of water buffaloes (Bubalus bubalis) with bovine viral diarrhea viruses (BVDV) in serologically negative animals.

    Science.gov (United States)

    Craig, María I; König, Guido A; Benitez, Daniel F; Draghi, María G

    2015-01-01

    Infection of water buffaloes (Bubalus bubalis) with bovine viral diarrhea viruses (BVDV) has been confirmed in several studies by serological and molecular techniques. In order to determine the presence of persistently infected animals and circulating species and subtypes of BVDV we conducted this study on a buffalo herd, whose habitat was shared with bovine cattle (Bossp.). Our serological results showed a high level of positivity for BVDV-1 and BVDV-2 within the buffalo herd. The molecular analyses of blood samples in serologically negative animals revealed the presence of viral nucleic acid, confirming the existence of persistent infection in the buffaloes. Cloning and sequencing of the 5' UTR of some of these samples revealed the presence of naturally mix-infected buffaloes with at least two different subtypes (1a and 1b), and also with both BVDV species (BVDV-1 and BVDV-2).

  16. Feasibility of Using the Mosquito Blood Meal for Rapid and Efficient Human and Animal Virus Surveillance and Discovery.

    Science.gov (United States)

    Yang, Yu; Garver, Lindsey S; Bingham, Karen M; Hang, Jun; Jochim, Ryan C; Davidson, Silas A; Richardson, Jason H; Jarman, Richard G

    2015-12-01

    Mosquito blood meals taken from humans and animals potentially represent a useful source of blood for the detection of blood-borne pathogens. In this feasibility study, Anopheles stephensi mosquitoes were fed with blood meals spiked with dengue virus type 2 (DENV-2) and harvested at serial time points. These mosquitoes are not competent vectors, and the virus is not expected to replicate. Ingested blood was spotted on Whatman FTA cards and stored at room temperature. Mosquito abdomens were removed and stored at -80°C. Control blood meal aliquots were stored in vials or applied onto FTA cards. After 4 weeks of storage, the samples were extracted using beadbeating and QIAamp Viral RNA kit (Qiagen Sciences, Germantown, MD). Recovered viral RNA was analyzed by DENV-2 TaqMan RT-PCR assay and next-generation sequencing (NGS). Overall viral RNA recovery efficiency was 15% from the directly applied dried blood spots and approximately 20% or higher for dried blood spots made by blotting mosquito midgut on FTA cards. Viral RNA in mosquito-ingested blood decreases over time, but remains detectable 24 hours after blood feeding. The viral sequences in FTA-stored specimens can be maintained at room temperature. The strategy has the potential utility in expedited zoonotic virus discovery and blood-borne pathogen surveillance. PMID:26416112

  17. 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

  18. Differentiation of infected and vaccinated animals (DIVA) using the NS1 protein of avian influenza virus

    Science.gov (United States)

    Vaccination against avian influenza (AI) virus, a powerful tool for control of the disease, may result in issues related to surveillance programs and international trade of poultry and poultry products. The use of AI vaccination in poultry would have greater world-wide acceptance if a reliable test...

  19. African swine fever virus excretion patterns in persistently infected animals: A quantitative approach

    NARCIS (Netherlands)

    Carvalho Ferreira, de H.C.; Weesendorp, E.; Elbers, A.R.W.; Bouma, A.; Quak, S.; Stegeman, J.A.; Loeffen, W.L.A.

    2012-01-01

    The continuing circulation of African swine fever (ASF) in Russia and in the Trans-Caucasian countries has led to increased efforts in characterizing the epidemiology of ASF. For a better insight in epidemiology, quantitative data on virus excretion is required. Until now, excretion data has mainly

  20. Peptide Mimicrying Between SARS Coronavirus Spike Protein and Human Proteins Reacts with SARS Patient Serum

    Directory of Open Access Journals (Sweden)

    K.-Y. Hwa

    2008-01-01

    Full Text Available Molecular mimicry, defined as similar structures shared by molecules from dissimilar genes or proteins, is a general strategy used by pathogens to infect host cells. Severe acute respiratory syndrome (SARS is a new human respiratory infectious disease caused by SARS coronavirus (SARS-CoV. The spike (S protein of SARS-CoV plays an important role in the virus entry into a cell. In this study, eleven synthetic peptides from the S protein were selected based on its sequence homology with human proteins. Two of the peptides D07 (residues 927–937 and D08 (residues 942–951 were recognized by the sera of SARS patients. Murine hyperimmune sera against these peptides bound to proteins of human lung epithelial cells A549. Another peptide D10 (residues 490–502 stimulated A549 to proliferate and secrete IL-8. The present results suggest that the selected S protein regions, which share sequence homology with human proteins, may play important roles in SARS-CoV infection.

  1. Monkeypox Virus Infections in Small Animal Models for Evaluation of Anti-Poxvirus Agents

    OpenAIRE

    Inger K Damon; Christina L Hutson

    2010-01-01

    An ideal animal model for the study of a human disease is one which utilizes a route of infection that mimics the natural transmission of the pathogen; the ability to obtain disease with an infectious dose equivalent to that causing disease in humans; as well having a disease course, morbidity and mortality similar to that seen with human disease. Additionally, the animal model should have a mode(s) of transmission that mimics human cases. The development of small animal models for the study ...

  2. Zika virus: An update on epidemiology, pathology, molecular biology, and animal model.

    Science.gov (United States)

    Ramos da Silva, Suzane; Gao, Shou-Jiang

    2016-08-01

    Zika virus (ZIKV) was first described in 1947, and became a health emergency problem in 2016 when its association with fetal microcephaly cases was confirmed by Centers for Disease Control and Prevention (CDC) in the United States. To date, ZIKV infection has been documented in 66 countries. ZIKV is recognized as a neurotropic virus and numerous diseases manifested in multiple neurological disorders have been described, mainly in countries that have been exposed to ZIKV after the 2007 outbreak in the Federated States of Micronesia. The most dramatic consequence of ZIKV infection documented is the abrupt increase in fetal microcephaly cases in Brazil. Here, we present an update of the published research progress in the past few months. J. Med. Virol. 88:1291-1296, 2016. © 2016 Wiley Periodicals, Inc. PMID:27124623

  3. Zika virus: An update on epidemiology, pathology, molecular biology, and animal model.

    Science.gov (United States)

    Ramos da Silva, Suzane; Gao, Shou-Jiang

    2016-08-01

    Zika virus (ZIKV) was first described in 1947, and became a health emergency problem in 2016 when its association with fetal microcephaly cases was confirmed by Centers for Disease Control and Prevention (CDC) in the United States. To date, ZIKV infection has been documented in 66 countries. ZIKV is recognized as a neurotropic virus and numerous diseases manifested in multiple neurological disorders have been described, mainly in countries that have been exposed to ZIKV after the 2007 outbreak in the Federated States of Micronesia. The most dramatic consequence of ZIKV infection documented is the abrupt increase in fetal microcephaly cases in Brazil. Here, we present an update of the published research progress in the past few months. J. Med. Virol. 88:1291-1296, 2016. © 2016 Wiley Periodicals, Inc.

  4. Neuronal injury in simian immunodeficiency virus and other animal models of neuroAIDS

    OpenAIRE

    Crews, Leslie; Lentz, Margaret R.; González, R. Gilberto; Fox, Howard S.; Masliah, Eliezer

    2008-01-01

    The success of antiretroviral therapy has reduced the incidence of severe neurological complication resulting from human immunodeficiency virus (HIV) infection. However, increased patient survival has been associated with an increased prevalence of protracted forms of HIV encephalitis leading to moderate cognitive impairment. NeuroAIDS remains a great challenge to patients, their families, and our society. Thus development of preclinical models that will be suitable for testing promising new ...

  5. Antiviral activity of a Bacillus sp. P34 peptide against pathogenic viruses of domestic animals

    Science.gov (United States)

    Silva, Débora Scopel e; de Castro, Clarissa Caetano; Silva, Fábio da Silva e; Sant’anna, Voltaire; Vargas, Gilberto D’Avila; de Lima, Marcelo; Fischer, Geferson; Brandelli, Adriano; da Motta, Amanda de Souza; Hübner, Silvia de Oliveira

    2014-01-01

    P34 is an antimicrobial peptide produced by a Bacillus sp. strain isolated from the intestinal contents of a fish in the Brazilian Amazon basin with reported antibacterial activity. The aim of this work was to evaluate the peptide P34 for its in vitro antiviral properties against canine adenovirus type 2 (CAV-2), canine coronavirus (CCoV), canine distemper virus (CDV), canine parvovirus type 2 (CPV-2), equine arteritis virus (EAV), equine influenza virus (EIV), feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1). The results showed that the peptide P34 exhibited antiviral activity against EAV and FHV-1. The peptide P34 inhibited the replication of EAV by 99.9% and FHV-1 by 94.4%. Virucidal activity was detected only against EAV. When P34 and EAV were incubated for 6 h at 37 °C the viral titer reduced from 104.5 TCID50 to 102.75 TCID50, showing a percent of inhibition of 98.6%. In conclusion, our results demonstrated that P34 inhibited EAV and FHV-1 replication in infected cell cultures and it showed virucidal activity against EAV. Since there is documented resistance to the current drugs used against herpesviruses and there is no treatment for equine viral arteritis, it is advisable to search for new antiviral compounds to overcome these infections. PMID:25477947

  6. Antiviral activity of a Bacillus sp: P34 peptide against pathogenic viruses of domestic animals

    Directory of Open Access Journals (Sweden)

    Débora Scopel e Silva

    2014-09-01

    Full Text Available P34 is an antimicrobial peptide produced by a Bacillus sp. strain isolated from the intestinal contents of a fish in the Brazilian Amazon basin with reported antibacterial activity. The aim of this work was to evaluate the peptide P34 for its in vitro antiviral properties against canine adenovirus type 2 (CAV-2, canine coronavirus (CCoV, canine distemper virus (CDV, canine parvovirus type 2 (CPV-2, equine arteritis virus (EAV, equine influenza virus (EIV, feline calicivirus (FCV and feline herpesvirus type 1 (FHV-1. The results showed that the peptide P34 exhibited antiviral activity against EAV and FHV-1. The peptide P34 inhibited the replication of EAV by 99.9% and FHV-1 by 94.4%. Virucidal activity was detected only against EAV. When P34 and EAV were incubated for 6 h at 37 °C the viral titer reduced from 10(4.5 TCID50 to 10(2.75 TCID50, showing a percent of inhibition of 98.6%. In conclusion, our results demonstrated that P34 inhibited EAV and FHV-1 replication in infected cell cultures and it showed virucidal activity against EAV. Since there is documented resistance to the current drugs used against herpesviruses and there is no treatment for equine viral arteritis, it is advisable to search for new antiviral compounds to overcome these infections.

  7. SAR: Stroke Authorship Recognition

    KAUST Repository

    Shaheen, Sara

    2015-10-15

    Are simple strokes unique to the artist or designer who renders them? If so, can this idea be used to identify authorship or to classify artistic drawings? Also, could training methods be devised to develop particular styles? To answer these questions, we propose the Stroke Authorship Recognition (SAR) approach, a novel method that distinguishes the authorship of 2D digitized drawings. SAR converts a drawing into a histogram of stroke attributes that is discriminative of authorship. We provide extensive classification experiments on a large variety of data sets, which validate SAR\\'s ability to distinguish unique authorship of artists and designers. We also demonstrate the usefulness of SAR in several applications including the detection of fraudulent sketches, the training and monitoring of artists in learning a particular new style and the first quantitative way to measure the quality of automatic sketch synthesis tools. © 2015 The Eurographics Association and John Wiley & Sons Ltd.

  8. Coronaviruses: emerging and re-emerging pathogens in humans and animals.

    Science.gov (United States)

    Lau, Susanna K P; Chan, Jasper F W

    2015-12-22

    The severe acute respiratory syndrome coronavirus (SARS-CoV) and recently emerged Middle East respiratory syndrome coronavirus (MERS-CoV) epidemics have proven the ability of coronaviruses to cross species barrier and emerge rapidly in humans. Other coronaviruses such as porcine epidemic diarrhea virus (PEDV) are also known to cause major disease epidemics in animals with huge economic loss. This special issue in Virology Journal aims to highlight the advances and key discoveries in the animal origin, viral evolution, epidemiology, diagnostics and pathogenesis of the emerging and re-emerging coronaviruses in both humans and animals.

  9. Influenza A virus infection of healthy piglets in an abattoir in Brazil: animal-human interface and risk for interspecies transmission

    Directory of Open Access Journals (Sweden)

    Ariane Ribeiro Amorim

    2013-08-01

    Full Text Available Asymptomatic influenza virus infections in pigs are frequent and the lack of measures for controlling viral spread facilitates the circulation of different virus strains between pigs. The goal of this study was to demonstrate the circulation of influenza A virus strains among asymptomatic piglets in an abattoir in Brazil and discuss the potential public health impacts. Tracheal samples (n = 330 were collected from asymptomatic animals by a veterinarian that also performed visual lung tissue examinations. No slaughtered animals presented with any noticeable macroscopic signs of influenza infection following examination of lung tissues. Samples were then analysed by reverse transcription-polymerase chain reaction that resulted in the identification of 30 (9% influenza A positive samples. The presence of asymptomatic pig infections suggested that these animals could facilitate virus dissemination and act as a source of infection for the herd, thereby enabling the emergence of influenza outbreaks associated with significant economic losses. Furthermore, the continuous exposure of the farm and abattoir workers to the virus increases the risk for interspecies transmission. Monitoring measures of swine influenza virus infections and vaccination and monitoring of employees for influenza infection should also be considered. In addition regulatory agencies should consider the public health ramifications regarding the potential zoonotic viral transmission between humans and pigs.

  10. Retrospective epidemiological evaluation of molecular and animal husbandry data within the bovine viral diarrhoea virus (BVDV) control programme in Western Austria during 2009-2014.

    Science.gov (United States)

    Schoepf, Karl; Revilla-Fernández, Sandra; Steinrigl, Adolf; Fuchs, Reinhard; Sailer, Andreas; Weikel, Joachim; Schmoll, Friedrich

    2016-01-01

    A retrospective epidemiological investigation of molecular and animal husbandry data collected over an observation period of five years (2009-2014) within the compulsory bovine viral diarrhoea virus (BVDV) control programme in Western Austria, covering the federal provinces of Tyrol and Vorarlberg is presented in this study. Samples collected from 232 infected calves were phylogenetically classified based on the 5' untranslated region (5'UTR). All but 13 samples, which were typed as border disease virus subtype 3 (BDV-3), belonged to the bovine viral diarrhoea virus genotype 1 (BVDV-1) and clustered within six different subtypes (1b, 1e, 1f, 1h, 1d and 1k). Movement data and survival times from infected individual animals were analysed because of their potential of passing on infection to naive herds. From the moment of submission of the laboratory results, 180 animals were culled within the first month, 13 lived longer than two but not longer than six months and seven infected animals lived longer than one year. 13 of the infected animals were born on alpine pastures and eleven infected animals were grazed on mountain pastures during summer. The movement of infected animals and the role of trade in alpine areas are a possible source for spreading the infection, thus hampering the progress of eradication.

  11. 42 CFR 71.56 - African rodents and other animals that may carry the monkeypox virus.

    Science.gov (United States)

    2010-10-01

    ... HUMAN SERVICES QUARANTINE, INSPECTION, LICENSING FOREIGN QUARANTINE Importations § 71.56 African rodents... Control and Prevention (CDC) from causing an animal to be quarantined, re-exported, or destroyed under a... obtain such written permission from CDC, you must send a written request to Division of Global...

  12. The pig as a large animal model for influenza a virus infection

    DEFF Research Database (Denmark)

    Skovgaard, Kerstin; Brogaard, Louise; Larsen, Lars Erik;

    It is increasingly realized that large animal models like the pig are exceptionally human like and serve as an excellent model for disease and inflammation. Pigs are fully susceptible to human influenza, share many similarities with humans regarding lung physiology and innate immune cell...

  13. A tale of two HSV-1 helicases: roles of phage and animal virus helicases in DNA replication and recombination.

    Science.gov (United States)

    Marintcheva, B; Weller, S K

    2001-01-01

    Helicases play essential roles in many important biological processes such as DNA replication, repair, recombination, transcription, splicing, and translation. Many bacteriophages and plant and animal viruses encode one or more helicases, and these enzymes have been shown to play many roles in their respective viral life cycles. In this review we concentrate primarily on the roles of helicases in DNA replication and recombination with special emphasis on the bacteriophages T4, T7, and A as model systems. We explore comparisons between these model systems and the herpesviruses--primarily herpes simplex virus. Bacteriophage utilize various pathways of recombination-dependent DNA replication during the replication of their genomes. In fact the study of recombination in the phage systems has greatly enhanced our understanding of the importance of recombination in the replication strategies of bacteria, yeast, and higher eukaryotes. The ability to "restart" the replication process after a replication fork has stalled or has become disrupted for other reasons is a critical feature in the replication of all organisms studied. Phage helicases and other recombination proteins play critical roles in the "restart" process. Parallels between DNA replication and recombination in phage and in the herpesviruses is explored. We and others have proposed that recombination plays an important role in the life cycle of the herpesviruses, and in this review, we discuss models for herpes simplex virus type 1 (HSV-1) DNA replication. HSV-1 encodes two helicases. UL9 binds specifically to the origins of replication and is believed to initiate HSV DNA replication by unwinding at the origin; the heterotrimeric helicase-primase complex, encoded by UL5, UL8, and UL52 genes, is believed to unwind duplex viral DNA at replication forks. Structure-function analyses of UL9 and the helicase-primase are discussed with attention to the roles these proteins might play during HSV replication. PMID

  14. A Genome-Wide Analysis of RNA Pseudoknots That Stimulate Efficient −1 Ribosomal Frameshifting or Readthrough in Animal Viruses

    Directory of Open Access Journals (Sweden)

    Xiaolan Huang

    2013-01-01

    Full Text Available Programmed −1 ribosomal frameshifting (PRF and stop codon readthrough are two translational recoding mechanisms utilized by some RNA viruses to express their structural and enzymatic proteins at a defined ratio. Efficient recoding usually requires an RNA pseudoknot located several nucleotides downstream from the recoding site. To assess the strategic importance of the recoding pseudoknots, we have carried out a large scale genome-wide analysis in which we used an in-house developed program to detect all possible H-type pseudoknots within the genomic mRNAs of 81 animal viruses. Pseudoknots are detected downstream from ~85% of the recoding sites, including many previously unknown pseudoknots. ~78% of the recoding pseudoknots are the most stable pseudoknot within the viral genomes. However, they are not as strong as some designed pseudoknots that exhibit roadblocking effect on the translating ribosome. Strong roadblocking pseudoknots are not detected within the viral genomes. These results indicate that the decoding pseudoknots have evolved to possess optimal stability for efficient recoding. We also found that the sequence at the gag-pol frameshift junction of HIV1 harbors potential elaborated pseudoknots encompassing the frameshift site. A novel mechanism is proposed for possible involvement of the elaborated pseudoknots in the HIV1 PRF event.

  15. ESTUDIO TEÓRICO DEL VIRUS DEL SÍNDROME RESPIRATORIO AGUDO SEVERO (SARS A TRAVÉS DEL USO DE MÉTODOS DE ACOPLAMIENTO MOLECULAR

    Directory of Open Access Journals (Sweden)

    Ricardo Vivas Reyes

    2010-03-01

    Full Text Available En este estudio se ha evaluado por medio de la metodología de acoplamiento molecular una serie de 5 ligandos borados, que son variantes de la molécula FL-078. Estas moléculas tienen actividad inhibitoria frente a la proteasa Mpro responsable de la replicación del SARS-CoV. Haciendo uso del programa SYBYL7.0 se optimizó el homodímero de la Mpro (código 1Q2W, y a través del software FlexX se hizo el acople molecular con el fin de escoger el confórmero más estable de los ligandos aril borados frente a la macromolécula Mpro, encontrándose que la estructura FL-166 fue la de mejor conformación. Los 5 ligandos aril borados tienen la propiedad de interaccionar con el grupo hidroxilo (OH presente en los residuos tales como serinas, treoninas y tirosinas. Los resultados acople molecular muestran que el mejor acercamiento sobre la cavidad se da sobre el conjunto de treoninas 21, 24, 25 y 26, y no como se afirma en la literatura: que se da sobre el conjunto de serinas 139, 144 y 147.

  16. SAR antenna calibration techniques

    Science.gov (United States)

    Carver, K. R.; Newell, A. C.

    1978-01-01

    Calibration of SAR antennas requires a measurement of gain, elevation and azimuth pattern shape, boresight error, cross-polarization levels, and phase vs. angle and frequency. For spaceborne SAR antennas of SEASAT size operating at C-band or higher, some of these measurements can become extremely difficult using conventional far-field antenna test ranges. Near-field scanning techniques offer an alternative approach and for C-band or X-band SARs, give much improved accuracy and precision as compared to that obtainable with a far-field approach.

  17. Metabolic effects of influenza virus infection in cultured animal cells: Intra- and extracellular metabolite profiling

    Directory of Open Access Journals (Sweden)

    Genzel Yvonne

    2010-05-01

    Full Text Available Abstract Background Many details in cell culture-derived influenza vaccine production are still poorly understood and approaches for process optimization mainly remain empirical. More insights on mammalian cell metabolism after a viral infection could give hints on limitations and cell-specific virus production capacities. A detailed metabolic characterization of an influenza infected adherent cell line (MDCK was carried out based on extracellular and intracellular measurements of metabolite concentrations. Results For most metabolites the comparison of infected (human influenza A/PR/8/34 and mock-infected cells showed a very similar behavior during the first 10-12 h post infection (pi. Significant changes were observed after about 12 h pi: (1 uptake of extracellular glucose and lactate release into the cell culture supernatant were clearly increased in infected cells compared to mock-infected cells. At the same time (12 h pi intracellular metabolite concentrations of the upper part of glycolysis were significantly increased. On the contrary, nucleoside triphosphate concentrations of infected cells dropped clearly after 12 h pi. This behaviour was observed for two different human influenza A/PR/8/34 strains at slightly different time points. Conclusions Comparing these results with literature values for the time course of infection with same influenza strains, underline the hypothesis that influenza infection only represents a minor additional burden for host cell metabolism. The metabolic changes observed after12 h pi are most probably caused by the onset of apoptosis in infected cells. The comparison of experimental data from two variants of the A/PR/8/34 virus strain (RKI versus NIBSC with different productivities and infection dynamics showed comparable metabolic patterns but a clearly different timely behavior. Thus, infection dynamics are obviously reflected in host cell metabolism.

  18. The human and animal health impacts of introduction and spread of an exotic strain of West Nile virus in Australia.

    Science.gov (United States)

    Hernández-Jover, Marta; Roche, Sharon; Ward, Michael P

    2013-05-01

    Vector-borne diseases can have substantial impacts on human and animal health, including major epidemics. West Nile virus (WNV) is of particular international importance due to its recent emergence and impact in the Western Hemisphere. Despite the presence of a sub-type of WNV (Kunjin virus, KUN) in Australia, a potential ecological niche could be occupied by an exotic strain of WNV of the North American type. This study assesses the probability an exotic strain of WNV enters Australia via an infected mosquito in an aircraft from the United States (U.S.) landing at Sydney airport, the probability it spreads to susceptible species and the impact of the resulting outbreak on human and animal health. A release, exposure and consequence assessment were conducted using expert opinion and scientific literature to parameterise the inputs for the models (OIE, 2009). Following establishment of WNV in Australia, the spatio-temporal spread of WNV was predicted over a six year period based on the Australian human and equine populations at-risk, the known distribution of other mosquito-borne flaviviruses in Australia, climatic factors, and the spread of WNV in the U.S. following it's incursion in New York City in 1999. The impact of this spread was measured as a multiplier of human and equine demographics using the U.S. incidence and case fatality rates as a reference. For an 8 month period from September to April (considering seasonal impact on mosquito activity during the coldest months in Australia and the U.S.), and assuming WNV is endemic in the U.S., the median probability an infected mosquito is introduced is 0.17, and the median number of infected mosquitoes introduced is predicted to be zero, with a 95th percentile range of one. The overall probability of a WNV outbreak (WNV released into Australia, susceptible hosts exposed and the virus spread) occurring in the human and the horse population during this time period is estimated to be 7.0×10(-6) and 3.9×10

  19. Suppression of RNAi by dsRNA-degrading RNaseIII enzymes of viruses in animals and plants.

    Directory of Open Access Journals (Sweden)

    Isabel Weinheimer

    2015-03-01

    Full Text Available Certain RNA and DNA viruses that infect plants, insects, fish or poikilothermic animals encode Class 1 RNaseIII endoribonuclease-like proteins. dsRNA-specific endoribonuclease activity of the RNaseIII of rock bream iridovirus infecting fish and Sweet potato chlorotic stunt crinivirus (SPCSV infecting plants has been shown. Suppression of the host antiviral RNA interference (RNAi pathway has been documented with the RNaseIII of SPCSV and Heliothis virescens ascovirus infecting insects. Suppression of RNAi by the viral RNaseIIIs in non-host organisms of different kingdoms is not known. Here we expressed PPR3, the RNaseIII of Pike-perch iridovirus, in the non-hosts Nicotiana benthamiana (plant and Caenorhabditis elegans (nematode and found that it cleaves double-stranded small interfering RNA (ds-siRNA molecules that are pivotal in the host RNA interference (RNAi pathway and thereby suppresses RNAi in non-host tissues. In N. benthamiana, PPR3 enhanced accumulation of Tobacco rattle tobravirus RNA1 replicon lacking the 16K RNAi suppressor. Furthermore, PPR3 suppressed single-stranded RNA (ssRNA--mediated RNAi and rescued replication of Flock House virus RNA1 replicon lacking the B2 RNAi suppressor in C. elegans. Suppression of RNAi was debilitated with the catalytically compromised mutant PPR3-Ala. However, the RNaseIII (CSR3 produced by SPCSV, which cleaves ds-siRNA and counteracts antiviral RNAi in plants, failed to suppress ssRNA-mediated RNAi in C. elegans. In leaves of N. benthamiana, PPR3 suppressed RNAi induced by ssRNA and dsRNA and reversed silencing; CSR3, however, suppressed only RNAi induced by ssRNA and was unable to reverse silencing. Neither PPR3 nor CSR3 suppressed antisense-mediated RNAi in Drosophila melanogaster. These results show that the RNaseIII enzymes of RNA and DNA viruses suppress RNAi, which requires catalytic activities of RNaseIII. In contrast to other viral silencing suppression proteins, the RNaseIII enzymes are

  20. Coronaviruses (MERS and SARS)

    Science.gov (United States)

    ... the globe have initiated studies to understand the Middle East respiratory syndrome coronavirus (MERS-CoV)—and how to stop it. Coronaviruses About Coronaviruses Middle East Respiratory Syndrome (MERS) Severe Acute Respiratory Syndrome (SARS) ...

  1. SARS-like cluster of circulating bat coronavirus pose threat for human emergence

    Science.gov (United States)

    Menachery, Vineet D.; Yount, Boyd L.; Debbink, Kari; Agnihothram, Sudhakar; Gralinski, Lisa E.; Plante, Jessica A.; Graham, Rachel L.; Scobey, Trevor; Ge, Xing-Yi; Donaldson, Eric F.; Randell, Scott H.; Lanzavecchia, Antonio; Marasco, Wayne A.; Shi, Zhengli-Li; Baric, Ralph S.

    2016-01-01

    The emergence of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and Middle East Respiratory Syndrome (MERS)-CoV underscores the threat of cross-species transmission events leading to outbreaks in humans. In this study, we examine the disease potential for SARS-like CoVs currently circulating in Chinese horseshoe bat populations. Utilizing the SARS-CoV infectious clone, we generated and characterized a chimeric virus expressing the spike of bat coronavirus SHC014 in a mouse adapted SARS-CoV backbone. The results indicate that group 2b viruses encoding the SHC014 spike in a wild type backbone can efficiently utilize multiple ACE2 receptor orthologs, replicate efficiently in primary human airway cells, and achieve in vitro titers equivalent to epidemic strains of SARS-CoV. Additionally, in vivo experiments demonstrate replication of the chimeric virus in mouse lung with notable pathogenesis. Evaluation of available SARS-based immune-therapeutic and prophylactic modalities revealed poor efficacy; both monoclonal antibody and vaccine approaches failed to neutralize and protect from CoVs utilizing the novel spike protein. Importantly, based on these findings, we synthetically rederived an infectious full length SHC014 recombinant virus and demonstrate robust viral replication both in vitro and in vivo. Together, the work highlights a continued risk of SARS-CoV reemergence from viruses currently circulating in bat populations. PMID:26552008

  2. A Natural Product as Drug Lead against both SARS and Flu

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ In cooperation with colleagues of Singapore Polytechnic, CAS scientists have discovered a natural product from fruits that could be a drug lead to battle both severe acute respiratory syndrome (SARS) and flu viruses.

  3. Detection of Rift Valley Fever Virus Interepidemic Activity in Some Hotspot Areas of Kenya by Sentinel Animal Surveillance, 2009–2012

    Directory of Open Access Journals (Sweden)

    Jacqueline Kasiiti Lichoti

    2014-01-01

    Full Text Available Rift Valley fever virus causes an important zoonotic disease of humans and small ruminants in Eastern Africa and is spread primarily by a mosquito vector. In this region, it occurs as epizootics that typically occur at 5–15-year intervals associated with unusual rainfall events. It has hitherto been known that the virus is maintained between outbreaks in dormant eggs of the mosquito vector and this has formed the basis of understanding of the epidemiology and control strategies of the disease. We show here that seroconversion and sporadic acute disease do occur during the interepidemic periods (IEPs in the absence of reported cases in livestock or humans. The finding indicates that previously undetected low-level virus transmission during the IEPs does occur and that epizootics may also be due to periodic expansion of mosquito vectors in the presence of both circulating virus and naïve animals.

  4. Association of Hepatitis C Virus With Insulin Resistance: Evidences From Animal Studies and Clinical Studie

    Directory of Open Access Journals (Sweden)

    Sadaf Badar

    2012-01-01

    Full Text Available Context: HCV infection is strongly associated with development of insulin resistance and type-2 diabetes, however molecular mechanism of these associations is not known. The aim of this review was to conduct a comprehensive literature search to understand the nature of the association between hepatitis C virus (HCV infection and insulin resistance (IR. We also explored the role of HCV core protein and NS5a in modulating the course of the insulin-signaling pathway.Evidence Acquisitions: We searched Directory of Open Access Journals (DOAJ Google Scholar, Pubmed (NLM, LISTA (EBSCO, Web of Science (TS and PakMediNet.Results: Emerging evidence suggests an association between HCV infection and carotid/coronary vascular disease. IR appears to be a dominant underlying cause of accelerated atherosclerosis in patients with chronic hepatitis C (CHC. HCV can induce IR directly through the stimulation of SOCS3 and PPA2, and both of these molecules have been shown to inhibit interferon-α signaling. Improvement of insulin sensitivity may increase the response rate to antiviral treatment and prevent IR complications, including vascular diseases. The results of several clinical trials that have used insulin sensitizers (metformin and PPAR-γ agonists have been inconclusive.Conclusions: Beside the association between HCV and IR, the published data also have showed the possible association of HCV core and NS5A protein with IR.

  5. Evolution and Variation of the SARS-CoV Genome

    Institute of Scientific and Technical Information of China (English)

    Jianfei Hu; Zizhang Zhang; Wei Wei; Songgang Li; Jun Wang; Jian Wang; Jun Yu; Huanming Yang; Jing Wang; Jing Xu; Wei Li; Yujun Han; Yan Li; Jia Ji; Jia Ye; Zhao Xu

    2003-01-01

    Knowledge of the evolution of pathogens is of great medical and biological significance to the prevention, diagnosis, and therapy of infectious diseases. In order to understand the origin and evolution of the SARS-CoV (severe acute respiratory syndrome-associated coronavirus), we collected complete genome sequences of all viruses available in GenBank, and made comparative analyses with the SARSCoV. Genomic signature analysis demonstrates that the coronaviruses all take the TGTT as their richest tetranucleotide except the SARS-CoV. A detailed analysis of the forty-two complete SARS-CoV genome sequences revealed the existence of two distinct genotypes, and showed that these isolates could be classified into four groups. Our manual analysis of the BLASTN results demonstrates that the HE (hemagglutinin-esterase) gene exists in the SARS-CoV, and many mutations made it unfamiliar to us.

  6. 模型动物在动物流感病毒传播机制研究中的应用%The Use of Animal Model in the Study of Transmissibility of Animal Influenza Virus

    Institute of Scientific and Technical Information of China (English)

    高玉伟; 桑晓宇; 夏咸柱

    2011-01-01

    Animal influenza not only can cause huge economic damage to livestock and poultry breeding business, but also cause public; health crisis and pandemic in human by crossing the species barrier. Using animal model could help us to understand the transmissibility of influenza virus. We reviewed the influenza A virus host ranges, host restriction factors, and the use of animal model in the study of transmissibility of animal influenza virus.%动物流感(influenza)不仅会对畜禽养殖业造成巨大的经济损失,而且可以跨越种间障碍进入人群,引发全球性的公共卫生危机和灾难性后果.模型动物是研究流感传播机制的重要基础.模型动物的使用有助于我们对流感病毒传播机制的深入了解.本文从流感病毒的宿主范围、常用模型动物的宿主限制因素和模型动物在流感病毒跨种传播机制中的选择与应用等三个方面进行了综述.

  7. The use of non-structural proteins of foot and mouth disease virus (FMDV) to differentiate between vaccinated and infected animals

    International Nuclear Information System (INIS)

    The Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture has a long history of coordinating isotope aided research projects for improving animal productivity in developing countries. Foot and mouth disease (FMD) remains a tremendous problem in developing countries and is a constant threat to developed countries. Tests to determine the immune status of animals form the basis of understanding the control of the disease. Vaccination is widely employed and has to be on a continuous basis. The antibodies produced against the FMD virus (FMDV) after infection are the same as those produced on vaccination. However, tests have been devised to use non-structural proteins (NSP) of FMDV since it is only on infection that antibodies are produced against such proteins. Thus, through their specific detection, it is possible to determine whether animals are infected in the face of vaccination. This is important since any contact with replicating virus in cattle, sheep and goats may result in a non-clinical situation where virus is carried by the affected animal without symptoms, and may be a threat to others. There is great suspicion over animals where virus has multiplied and so their identification is paramount and essential where countries are trying to demonstrate virus freedom. There have been many developments in this field and the IAEA sought to try and validate methods in this coordinated research project (CRP). Validation per se is always addressed by the IAEA and they have been instrumental in improving guidelines for test certification through the OIE. Although FMD tests had been devised they were not fully examined in a large geographical spread, nor were they compared directly. During the CRP many variations of tests were produced and this complicated the validation process. The resulting TECDOC reflects the relative instability of developments but value adds to the latest opinions on the use of NSP tests in the control of FMD. Several commercial kits

  8. Self-assembly of a nine-residue amyloid-forming peptide fragment of SARS corona virus E-protein: mechanism of self aggregation and amyloid-inhibition of hIAPP.

    Science.gov (United States)

    Ghosh, Anirban; Pithadia, Amit S; Bhat, Jyotsna; Bera, Supriyo; Midya, Anupam; Fierke, Carol A; Ramamoorthy, Ayyalusamy; Bhunia, Anirban

    2015-04-01

    Molecular self-assembly, a phenomenon widely observed in nature, has been exploited through organic molecules, proteins, DNA, and peptides to study complex biological systems. These self-assembly systems may also be used in understanding the molecular and structural biology which can inspire the design and synthesis of increasingly complex biomaterials. Specifically, use of these building blocks to investigate protein folding and misfolding has been of particular value since it can provide tremendous insights into peptide aggregation related to a variety of protein misfolding diseases, or amyloid diseases (e.g., Alzheimer's disease, Parkinson's disease, type-II diabetes). Herein, the self-assembly of TK9, a nine-residue peptide of the extra membrane C-terminal tail of the SARS corona virus envelope, and its variants were characterized through biophysical, spectroscopic, and simulated studies, and it was confirmed that the structure of these peptides influences their aggregation propensity, hence, mimicking amyloid proteins. TK9, which forms a beta-sheet rich fibril, contains a key sequence motif that may be critical for beta-sheet formation, thus making it an interesting system to study amyloid fibrillation. TK9 aggregates were further examined through simulations to evaluate the possible intra- and interpeptide interactions at the molecular level. These self-assembly peptides can also serve as amyloid inhibitors through hydrophobic and electrophilic recognition interactions. Our results show that TK9 inhibits the fibrillation of hIAPP, a 37 amino acid peptide implicated in the pathology of type-II diabetes. Thus, biophysical and NMR experimental results have revealed a molecular level understanding of peptide folding events, as well as the inhibition of amyloid-protein aggregation are reported.

  9. Phylogeny of SARS-CoV as inferred from complete genome comparison

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    SARS-CoV, as the pathogeny of severe acute respiratory syndrome (SARS), is a mystery that the origin of the virus is still unknown even a few isolates of the virus were completely sequenced. To explore the genesis of SARS-CoV, the FDOD method previously developed by us was applied to comparing complete genomes from 12 SARS-CoV isolates to those from 12 previously identified coronaviruses and an unrooted phylogenetic tree was constructed. Our results show that all SARS-CoV isolates were clustered into a clique and previously identified coronaviruses formed the other clique. Meanwhile, the three groups of coronaviruses depart from each other clearly in our tree that is consistent with the results of prevenient papers. Differently, from the topology of the phylogenetic tree we found that SARS-CoV is more close to group 1 within genus coronavirus. The topology map also shows that the 12 SARS-CoV isolates may be divided into two groups determined by the association with the SARS-CoV from the Hotel M in Hong Kong that may give some information about the infectious relationship of the SARS.

  10. Crop Classification by Polarimetric SAR

    DEFF Research Database (Denmark)

    Skriver, Henning; Svendsen, Morten Thougaard; Nielsen, Flemming;

    1999-01-01

    Polarimetric SAR-data of agricultural fields have been acquired by the Danish polarimetric L- and C-band SAR (EMISAR) during a number of missions at the Danish agricultural test site Foulum during 1995. The data are used to study the classification potential of polarimetric SAR data using...

  11. Molecular characterization of SAT 2 foot-and-mouth disease virus from post-outbreak slaughtered animals: implications for disease control in Uganda

    DEFF Research Database (Denmark)

    Balinda, Sheila N; Belsham, Graham; Masembe, Charles;

    2010-01-01

    In Uganda, limiting the extent of foot-and-mouth disease (FMD) spread during outbreaks involves short term measures such as ring vaccination and restrictions to the movement of livestock and their products to and from the affected areas. In this study, the presence of FMD virus RNA was investigated...... in cattle samples, three months after FMD quarantine measures had been lifted in the area in 2004 following an outbreak. Oropharyngeal tissue samples were obtained from 12 cattle slaughtered in a small town abattoir of Kiboga. FMD virus RNA was detected by diagnostic RT- PCR in 9 of the 12 tissue samples....... Part of the coding region for the capsid protein VP1 was amplified and sequenced. All samples were identified as belonging to the SAT 2 serotype. The implications for FMD control of both virus introductions into Uganda and the presence of carrier animals following outbreaks are discussed....

  12. Molecular characterization of SAT 2 foot-and-mouth disease virus from post-outbreak slaughtered animals: implications for disease control in Uganda.

    Science.gov (United States)

    Balinda, S N; Belsham, G J; Masembe, C; Sangula, A K; Siegismund, H R; Muwanika, V B

    2010-08-01

    In Uganda, limiting the extent of foot-and-mouth disease (FMD) spread during outbreaks involves short-term measures such as ring vaccination and restrictions of the movement of livestock and their products to and from the affected areas. In this study, the presence of FMD virus RNA was investigated in cattle samples 3 months after FMD quarantine measures had been lifted following an outbreak in 2004. Oropharyngeal tissue samples were obtained from 12 cattle slaughtered in a small town abattoir in Kiboga. FMD virus RNA was detected by diagnostic RT-PCR in nine of the 12 tissue samples. Part of the coding region for the capsid protein VP1 was amplified and sequenced. All samples were identified as belonging to the SAT 2 serotype. The implications for FMD control of both virus introduction into Uganda and the presence of carrier animals following outbreaks are discussed. PMID:20003615

  13. Rapid inactivation of SARS-like coronaviruses.

    Energy Technology Data Exchange (ETDEWEB)

    Kapil, Sanjay (Kansas State University, Manhattan, KS); Oberst, R. D. (Kansas State University, Manhattan, KS); Bieker, Jill Marie; Tucker, Mark David; Souza, Caroline Ann; Williams, Cecelia Victoria

    2004-03-01

    Chemical disinfection and inactivation of viruses is largely understudied, but is very important especially in the case of highly infectious viruses. The purpose of this LDRD was to determine the efficacy of the Sandia National Laboratories developed decontamination formulations against Bovine Coronavirus (BCV) as a surrogate for the coronavirus that causes Severe Acute Respiratory Syndrome (SARS) in humans. The outbreak of SARS in late 2002 resulted from a highly infectious virus that was able to survive and remain infectious for extended periods. For this study, preliminary testing with Escherichia coli MS-2 (MS-2) and Escherichia coli T4 (T4) bacteriophages was conducted to develop virucidal methodology for verifying the inactivation after treatment with the test formulations following AOAC germicidal methodologies. After the determination of various experimental parameters (i.e. exposure, concentration) of the formulations, final testing was conducted on BCV. All experiments were conducted with various organic challenges (horse serum, bovine feces, compost) for results that more accurately represent field use condition. The MS-2 and T4 were slightly more resistant than BCV and required a 2 minute exposure while BCV was completely inactivated after a 1 minute exposure. These results were also consistent for the testing conducted in the presence of the various organic challenges indicating that the test formulations are highly effective for real world application.

  14. In-Vitro Experiments on the Radiosensitivity of Foot-and-Mouth Disease Virus and other Animal Viruses to the Direct Effect of X-Irradiation

    International Nuclear Information System (INIS)

    Various in-vitro techniques have been used to observe the direct X-ray inactivation of foot-and-mouth disease virus, vesicular stomatitis virus and the virus of Teschen disease. All these methods were intended to eliminate the indirect effects of the irradiation, and for each virus an upper limit to the radioresistance was observed, which was assumed to correspond to inactivation by the direct effect. Further confirmation of the absence of indirect effects was obtained by observing the dose-rate and the concentration-independent survival curves, and by direct observation of the inactivated virus in the electron microscope. Virus suffering only direct inactivation retained its morphological integrity at a much higher radiation dose level (relative to loss of infectivity) than virus which was exposed to some residual indirect effects. These results are of value since the radio resistances observed represent the upper limits which may have to be taken into account in, for example, the elimination of foot-and-mouth disease virus from frozen meat. (author)

  15. Phylogeographic Reconstructions of a Rift Valley Fever Virus Strain Reveals Transboundary Animal Movements from Eastern Continental Africa to the Union of the Comoros.

    Science.gov (United States)

    Maquart, M; Pascalis, H; Abdouroihamane, S; Roger, M; Abdourahime, F; Cardinale, E; Cêtre-Sossah, C

    2016-04-01

    Major explosive outbreaks of Rift Valley fever (RVF), an arthropod borne zoonotic disease, occur in humans and animals with significant mortality and economic impact across continental Africa and the Indian Ocean region (Madagascar, the Comoros archipelago). Recently, sporadic human cases have been reported in Mayotte and Grande Comore, two islands belonging to the Comoros archipelago. To identify the hypothetical source of virus introduction in an inter-epidemic or a post-epidemic period, a longitudinal survey of livestock was set up in Comorian ruminant populations, known to be susceptible hosts. The phylogeographic genomic analysis has shown that RVF virus (RVFV) detected in a zebu collected in Anjouan in August 2011 seems to be related to the last known epidemic of RVF which occurred in East Africa and Madagascar (2007-2009). This result highlights the fact that RVFV is maintained within local livestock populations and transboundary animal movements from eastern continental Africa to Indian Ocean islands likely result in RVFV crossover.

  16. Absence of cytotoxic antibody to human immunodeficiency virus-infected cells in humans and its induction in animals after infection or immunization with purified envelope glycoprotein gp120

    International Nuclear Information System (INIS)

    The presence of antibody-dependent complement-mediated cytotoxicity (ACC) was assessed in humans and chimpanzees, which are capable of infection with human immunodeficiency virus isolate HTLV-IIIb, and examined in the goat after immunization with the major viral glycoprotein (gp120) of HTLV-IIIb. In infected humans no antibody mediating ACC was observed regardless of the status of disease. Even healthy individuals with high-titer, broadly reactive, neutralizing antibodies has no ACC. In contrast, chimpanzees infected with HTLV-IIIb, from whom virus could be isolated, not only had neutralizing antibody but also antibodies broadly reactive in ACC, even against distantly related human immunodeficiency virus isolates, as well as against their own reisolated virus. In the goat, the gp120 of HTLV-IIIb induced a highly type-specific response as measured by both ACC and flow cytofluorometry of live infected H9 cells. Normal human cells were not subject to ACC by animal anti-HTLV-III gp120-specific sera. Induction of ACC and neutralizing antibody were closely correlated in the animal experimental models but not in humans. The presence of ACC in gp120-inoculated goats and HTLV-III-infected chimpanzees represent a qualitative difference that may be important in the quest for the elicitation of a protective immunity in humans

  17. A double epidemic model for the SARS propagation

    Directory of Open Access Journals (Sweden)

    Turinici Gabriel

    2003-09-01

    Full Text Available Abstract Background An epidemic of a Severe Acute Respiratory Syndrome (SARS caused by a new coronavirus has spread from the Guangdong province to the rest of China and to the world, with a puzzling contagion behavior. It is important both for predicting the future of the present outbreak and for implementing effective prophylactic measures, to identify the causes of this behavior. Results In this report, we show first that the standard Susceptible-Infected-Removed (SIR model cannot account for the patterns observed in various regions where the disease spread. We develop a model involving two superimposed epidemics to study the recent spread of the SARS in Hong Kong and in the region. We explore the situation where these epidemics may be caused either by a virus and one or several mutants that changed its tropism, or by two unrelated viruses. This has important consequences for the future: the innocuous epidemic might still be there and generate, from time to time, variants that would have properties similar to those of SARS. Conclusion We find that, in order to reconcile the existing data and the spread of the disease, it is convenient to suggest that a first milder outbreak protected against the SARS. Regions that had not seen the first epidemic, or that were affected simultaneously with the SARS suffered much more, with a very high percentage of persons affected. We also find regions where the data appear to be inconsistent, suggesting that they are incomplete or do not reflect an appropriate identification of SARS patients. Finally, we could, within the framework of the model, fix limits to the future development of the epidemic, allowing us to identify landmarks that may be useful to set up a monitoring system to follow the evolution of the epidemic. The model also suggests that there might exist a SARS precursor in a large reservoir, prompting for implementation of precautionary measures when the weather cools down.

  18. Multichannel FMCW SAR

    NARCIS (Netherlands)

    Rossum, W.L. van; Otten, M.P.G.; Dorp, Ph. van

    2012-01-01

    A light weight SAR, suitable for use on short range tactical UAV, has been designed and built. The system consists of a fully digital receive array, and a very compact active transmit antenna. The approximate weight of the complete system is 6 kg, with power consumption below 75 W, depending on the

  19. Bistatic SAR: Proof of Concept.

    Energy Technology Data Exchange (ETDEWEB)

    Yocky, David A.; Doren, Neall E.; Bacon, Terry A.; Wahl, Daniel E.; Eichel, Paul H.; Jakowatz, Charles V,; Delaplain, Gilbert G.; Dubbert, Dale F.; Tise, Bertice L.; White, Kyle R.

    2014-10-01

    Typical synthetic aperture RADAR (SAR) imaging employs a co-located RADAR transmitter and receiver. Bistatic SAR imaging separates the transmitter and receiver locations. A bistatic SAR configuration allows for the transmitter and receiver(s) to be in a variety of geometric alignments. Sandia National Laboratories (SNL) / New Mexico proposed the deployment of a ground-based RADAR receiver. This RADAR receiver was coupled with the capability of digitizing and recording the signal collected. SNL proposed the possibility of creating an image of targets the illuminating SAR observes. This document describes the developed hardware, software, bistatic SAR configuration, and its deployment to test the concept of a ground-based bistatic SAR. In the proof-of-concept experiments herein, the RADAR transmitter will be a commercial SAR satellite and the RADAR receiver will be deployed at ground level, observing and capturing RADAR ground/targets illuminated by the satellite system.

  20. EARSEC SAR processing system

    Science.gov (United States)

    Protheroe, Mark; Sloggett, David R.; Sieber, Alois J.

    1994-12-01

    Traditionally, the production of high quality Synthetic Aperture Radar imagery has been an area where a potential user would have to expend large amounts of money in either the bespoke development of a processing chain dedicated to his requirements or in the purchase of a dedicated hardware platform adapted using accelerator boards and enhanced memory management. Whichever option the user adopted there were limitations based on the desire for a realistic throughput in data load and time. The user had a choice, made early in the purchase, for either a system that adopted innovative algorithmic manipulation, to limit the processing time of the purchase of expensive hardware. The former limits the quality of the product, while the latter excludes the user from any visibility into the processing chain. Clearly there was a need for a SAR processing architecture that gave the user a choice into the methodology to be adopted for a particular processing sequence, allowing him to decide on either a quick (lower quality) product or a detailed slower (high quality) product, without having to change the algorithmic base of his processor or the hardware platform. The European Commission, through the Advanced Techniques unit of the Joint Research Centre (JRC) Institute for Remote Sensing at Ispra in Italy, realizing the limitations on current processing abilities, initiated its own program to build airborne SAR and Electro-Optical (EO) sensor systems. This program is called the European Airborne Remote Sensing Capabilities (EARSEC) program. This paper describes the processing system developed for the airborne SAR sensor system. The paper considers the requirements for the system and the design of the EARSEC Airborne SAR Processing System. It highlights the development of an open SAR processing architecture where users have full access to intermediate products that arise from each of the major processing stages. It also describes the main processing stages in the overall

  1. SARS: clinical presentation, transmission, pathogenesis and treatment options.

    Science.gov (United States)

    Chan, Paul K S; Tang, Julian W; Hui, David S C

    2006-02-01

    SARS (severe acute respiratory syndrome) appeared as the first emerging infectious disease of this century. It is fortunate that the culprit virus can be grown without much difficulty from a commonly used cell line, allowing an unlimited supply of isolates for further molecular studies and leading to the development of sensitive diagnostic assays. How the virus has successfully jumped the species barrier is still a mystery. The superspreading events that occurred within hospital, hotel and high-density housing estate opens a new chapter in the mechanisms and routes of virus transmission. The old practice of quarantine proved to be still useful in controlling the global outbreak. Despite all the available sophisticated tests, alertness with early recognition by healthcare workers and prompt isolation of suspected cases is still the most important step for containing the spread of the infection. Although the rapidly evolving outbreak did not allow the conducting of systematic clinical trails to evaluate treatment options, the accumulated experience on managing SARS patients will improve the clinical outcome should SARS return. Although SARS led to more than 700 deaths worldwide, the lessons learnt have prepared healthcare systems worldwide to face future emerging and re-emerging infections. PMID:16411895

  2. SARS coronavirus entry into host cells through a novel clathrin- and caveolae-independent endocytic pathway

    Institute of Scientific and Technical Information of China (English)

    Hongliang Wang; Peng Yang; Kangtai Liu; Feng Guo; Yanli Zhang; Gongyi Zhang; Chengyu Jiang

    2008-01-01

    While severe acute respiratory syndrome coronavirus (SARS-CoV)fwas initially thought to enter cells through direct fusion with the plasma membrane, more recent evidence suggests that virus entry may also involve endocytosis. We have found that SARS-CoV enters cells via pH- and receptor-dependent endocytosis. Treatment of cells with either SARS-CoV spike protein or spike-bearing pseudoviruses resulted in the translocation of angiotensin-converting enzyme 2 (ACE2), the functional receptor of SARS-CoV, from the cell surface to endosomes. In addition, the spike-bearing pseudoviruses and early endosome antigen 1 were found to colocalize in endosomes. Further analyses using specific endocytic pathway inhibitors and dominant-negative Eps15 as well as caveolin-1 colocalization study suggested that virus entry was mediated by a clathrin- and caveolae-independent mechanism. Moreover, cholesterol- and sphingolipid-rich lipid raft microdomains in the plasma membrane, which have been shown to act as platforms for many physiological signaling pathways, were shown to be involved in virus entry. Endocytic entry of SARS-CoV may expand the cellular range of SARS-CoV infection, and our findings here contribute to the understanding of SARS-CoV pathogenesis, providing new information for anti-viral drug research.

  3. Bistatic sAR data processing algorithms

    CERN Document Server

    Qiu, Xiaolan; Hu, Donghui

    2013-01-01

    Synthetic Aperture Radar (SAR) is critical for remote sensing. It works day and night, in good weather or bad. Bistatic SAR is a new kind of SAR system, where the transmitter and receiver are placed on two separate platforms. Bistatic SAR is one of the most important trends in SAR development, as the technology renders SAR more flexible and safer when used in military environments. Imaging is one of the most difficult and important aspects of bistatic SAR data processing. Although traditional SAR signal processing is fully developed, bistatic SAR has a more complex system structure, so sign

  4. Detection, isolation and confirmation of Crimean-Congo hemorrhagic fever virus in human, ticks and animals in Ahmadabad, India, 2010-2011.

    Directory of Open Access Journals (Sweden)

    Devendra T Mourya

    Full Text Available BACKGROUND: In January 2011, human cases with hemorrhagic manifestations in the hospital staff were reported from a tertiary care hospital in Ahmadabad, India. This paper reports a detailed epidemiological investigation of nosocomial outbreak from the affected area of Ahmadabad, Gujarat, India. PRINCIPAL FINDINGS: Samples from 3 suspected cases, 83 contacts, Hyalomma ticks and livestock were screened for Crimean-Congo hemorrhagic fever (CCHF virus by qRT-PCR of which samples of two medical professionals (case C and E and the husband of the index case (case D were positive for CCHFV. The sensitivity and specificity of indigenous developed IgM ELISA to screen CCHFV specific antibodies in human serum was 75.0% and 97.5% respectively as compared to commercial kit. About 17.0% domestic animals from Kolat, Ahmadabad were positive for IgG antibodies while only two cattle and a goat showed positivity by qRT-PCR. Surprisingly, 43.0% domestic animals (Buffalo, cattle, sheep and goat showed IgG antibodies in the adjoining village Jivanpara but only one of the buffalo was positive for CCHFV. The Hyalomma anatolicum anatolicum ticks were positive in PCR and virus isolation. CCHFV was isolated from the blood sample of case C, E in Vero E-6 cells and Swiss albino mice. In partial nucleocapsid gene phylogeny from CCHFV positive human samples of the years 2010 and 2011, livestock and ticks showed this virus was similar to Tajikistan (strain TAJ/H08966, which belongs in the Asian/middle east genetic lineage IV. CONCLUSIONS: The likely source of CCHFV was identified as virus infected Hyalomma ticks and livestock at the rural village residence of the primary case (case A. In addition, retrospective sample analysis revealed the existence of CCHFV in Gujarat and Rajasthan states before this outbreak. An indigenous developed IgM ELISA kit will be of great use for screening this virus in India.

  5. SARS疫苗研究进展%The progress in research of SARS vaccine

    Institute of Scientific and Technical Information of China (English)

    张增峰

    2011-01-01

    Severe acute respiratory syndrome (SARS) is a serious infectious disease caused by SARSassociated coronavirus (SARS-CoV). There are no approved antiviral drugs that effectively target SARS-CoV,and vaccination is the most effective mode for preventing SARS in people. At present, SARS vaccines,including inactivated vaccines, attenuated vaccines, subunit vaccines and DNA vaccines, etc., are being developed. Progress has been made in animal models, and some of the vaccines have entered clinical trials. In this article, the current state of SARS vaccine development is reviewed.%严重急性呼吸综合征(severe acute respiratory syndrome,SARS)是由SARS相关冠状病毒(SARS-associated coronavirus,SARS-CoV)引起的一类严重的急性呼吸系统传染病.目前尚未研制出治疗SARS的有效药物,防范SARS-CoV感染最有效的方法是使用疫苗.正在研制的SARS疫苗有灭活疫苗、减毒活疫苗、亚单位疫苗和DNA疫苗等,这些疫苗在动物模型中取得一些进展,有的已进入人体试验.此文就近几年有关SARS疫苗的研发现状做一综述.

  6. SARS-CoV Genome Polymorphism: A Bioinformatics Study

    Institute of Scientific and Technical Information of China (English)

    Gordana M. Pavlovi(c)-Lazeti(c); Nenad S. Miti(c); Andrija M. Tomovi(c); Mirjana D. Pavlovi(c); Milo(s) V.Beljanski

    2005-01-01

    A dataset of 103 SARS-CoV isolates (101 human patients and 2 palm civets) was investigated on different aspects of genome polymorphism and isolate classification.The number and the distribution of single nucleotide variations (SNVs) and insertions and deletions, with respect to a "profile", were determined and discussed ("profile" being a sequence containing the most represented letter per position).Distribution of substitution categories per codon positions, as well as synonymous and non-synonymous substitutions in coding regions of annotated isolates, was determined, along with amino acid (a.a.) property changes. Similar analysis was performed for the spike (S) protein in all the isolates (55 of them being predicted for the first time). The ratio Ka/Ks confirmed that the S gene was subjected to the Darwinian selection during virus transmission from animals to humans. Isolates from the dataset were classified according to genome polymorphism and genotypes. Genome polymorphism yields to two groups, one with a small number of SNVs and another with a large number of SNVs, with up to four subgroups with respect to insertions and deletions. We identified three basic nine-locus genotypes:TTTT/TTCGG, CGCC/TTCAT, and TGCC/TTCGT, with four subgenotypes.Both classifications proposed are in accordance with the new insights into possible epidemiological spread, both in space and time.

  7. Possibility of using combined treatment of processing and ionizing radiation to eliminate contaminated viruses from non-screened donor of tissue allografts

    International Nuclear Information System (INIS)

    Full text: New emerging and re- emerging infectious diseases caused by viruses are outbreak and re- outbreak around the world. Most of the viruses come from animals ( zoonoses) and jump to human beings ( host jumping ) such as corona virus ( SARS), HIV, bird flu/ Avian flu H5N1, hepatitis viruses, Dengue fever virus, West Nile virus/WNV, Hantavirus, Marburg haemorrhagic fever virus, Hendra virus, Nipah virus etc. Transmission of those diseases through transplantation of contaminated tissue allograft to recipient can happened if the donor could not be screened properly. The donor can be well screened from some of those viruses such as HIV, hepatitis viruses and WNV. Processing of tissue allografts by pasteurization, washing and soaking in H2O2 and soap can eliminate contaminated viruses to a certain amount, have been reported by several authors. Viruses are very small microbes, they have DNA/RNA, resistant to radiation but to a certain degree they can be well eliminated by radiation. Their D10 - values vary from 4 to 13 kGy. This paper discribes briefly the possibility of using combined treatment of processing, lyophilization and sterilisation by radiation to overcome problems of non screened donor from some contaminated viruses. (Author)

  8. Identification of Immunogenic Determinants of the Spike Protein of SARS-like Coronavirus

    Institute of Scientific and Technical Information of China (English)

    Peng Zhou; Zhenggang Han; Lin-Fa Wang; Zhengli Shi

    2013-01-01

    Bat SARS-like coronavirus (SL-CoV) has a genome organization almost identical to that of SARS-CoV,but the N-terminus of the Spike (S) proteins,which interacts with host receptor and is a major target of neutralizing antibodies against CoVs,of the two viruses has only 63-64% sequence identity.Although there have been reports studying the overall immunogenicity of SSL,knowledge on the precise location of immunodominant determinants for SSL is still lacking.In this study,using a series of truncated expressed SSL fragments and SsL specific mouse sera,we identified two immunogenic determinants for SSL.Importantly,one of the two regions seems to be located in a region not shared by known immunogenic determinants of the SSARS.This finding will be of potential use in future monitoring of SL-CoV infection in bats and spillover animals and in development of more effective vaccine to cover broad protection against this new group of coronaviruses.

  9. Genome Wide Identification of SARS-CoV Susceptibility Loci Using the Collaborative Cross.

    Directory of Open Access Journals (Sweden)

    Lisa E Gralinski

    2015-10-01

    Full Text Available New systems genetics approaches are needed to rapidly identify host genes and genetic networks that regulate complex disease outcomes. Using genetically diverse animals from incipient lines of the Collaborative Cross mouse panel, we demonstrate a greatly expanded range of phenotypes relative to classical mouse models of SARS-CoV infection including lung pathology, weight loss and viral titer. Genetic mapping revealed several loci contributing to differential disease responses, including an 8.5Mb locus associated with vascular cuffing on chromosome 3 that contained 23 genes and 13 noncoding RNAs. Integrating phenotypic and genetic data narrowed this region to a single gene, Trim55, an E3 ubiquitin ligase with a role in muscle fiber maintenance. Lung pathology and transcriptomic data from mice genetically deficient in Trim55 were used to validate its role in SARS-CoV-induced vascular cuffing and inflammation. These data establish the Collaborative Cross platform as a powerful genetic resource for uncovering genetic contributions of complex traits in microbial disease severity, inflammation and virus replication in models of outbred populations.

  10. Expression and Purification of SARS Coronavirus Membrane Protein

    Institute of Scientific and Technical Information of China (English)

    戴五星; 雷明军; 吴少庭; 陈智浩; 梁靓; 潘晖榕; 秦莉; 高士同; 袁仕善; 张仁利

    2004-01-01

    To construct a recombinant plasmid Pet23a-M, the gene encoding severe acute respiratory syndrome (SARS) coronavirus membrane protein was amplified by RT-PCR and cloned into the expression plasmid Pet23a. Results of restriction endonuclease analysis, PCR detection and DNA sequencing analysis revealed that the cloned DNA sequence was the same as that reported. The re combinants were transformed into Escherichia coli (E. Coli) BL21 (DE3) and induced by Isopropylβ-D-thiogalactopyranoside (IPTG). The expression of 27 kD (1 kD=0. 992 1 ku) protein was detected by SDS-PAGE and pured by metal chelated chromatography. Results of Western-blot showed that this expressed protein could react with antibodies in sera of SARS patients during convalescence. This provided the basis for the further study on SARS virus vaccine and diagnostic agents.

  11. Conserved hemagglutinin peptides of influenza virus as potential multivalent vaccine candidate: characterization of immune response in different animal models

    OpenAIRE

    González Zabala, Juliana

    2016-01-01

    Los virus de influenza A (IAVs) son los responsables de brotes pandémicos y de la mayoría de las epidemias anuales en los seres humanos, aves y cerdos. Los virus de influenza A se dividen en subtipos, basado en la naturaleza de sus glicoproteínas de superficie, hemaglutinina (HA) y neuraminidasa (NA). La HA es una glicoproteína de superficie homotrimérica que media la entrada del virus de influenza a través de la unión celular y eventos de fusión de membranas. El bolsillo de unión al receptor...

  12. Novel Polarimetric SAR Interferometry Algorithms Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Polarimetric SAR interferometry (PolInSAR) is a recently developed synthetic aperture radar (SAR) imaging mode that combines the capabilities of radar polarimetry...

  13. Differentiation of foot-and-mouth disease virus infected animals from vaccinated animals using a blocking ELISA based on baculovirus expressed FMDV 3ABC antigen and a 3ABC monoclonal antibody

    DEFF Research Database (Denmark)

    Sørensen, K.J.; de Stricker, K.; Dyrting, K.C.;

    2005-01-01

    with homologous FMDV, positive reactions were obtained in all but one case. In some of these cattle the antibody response was detected late in comparison to the non-vaccinated infected cattle. The test gave results that compared favourably with two commercial ELISA's when used to test sera from cattle, pigs......A blocking ELISA that differentiated foot-and-mouth disease virus (FMDV) infected animals from vaccinated animals was developed which uses baculovirus expressed FMDV 3ABC non-structural protein as antigen and monoclonal antibody against FMDV 3ABC non-structural protein as capture and detector...... antibody. Sera from naive, vaccinated and infected cattle, sheep and pigs were examined. The specificity of the test was high. Non-specific reactions observed in particular in sera of cattle and sheep could be removed by filtration and inactivation. Positive reactions were obtained for sera from cattle...

  14. Nano(Q)SAR: Challenges, pitfalls and perspectives.

    Science.gov (United States)

    Tantra, Ratna; Oksel, Ceyda; Puzyn, Tomasz; Wang, Jian; Robinson, Kenneth N; Wang, Xue Z; Ma, Cai Y; Wilkins, Terry

    2015-01-01

    Regulation for nanomaterials is urgently needed, and the drive to adopt an intelligent testing strategy is evident. Such a strategy will not only provide economic benefits but will also reduce moral and ethical concerns arising from animal testing. For regulatory purposes, such an approach is promoted by REACH, particularly the use of quantitative structure-activity relationships [(Q)SAR] as a tool for the categorisation of compounds according to their physicochemical and toxicological properties. In addition to compounds, (Q)SAR has also been applied to nanomaterials in the form of nano(Q)SAR. Although (Q)SAR in chemicals is well established, nano(Q)SAR is still in early stages of development and its successful uptake is far from reality. This article aims to identify some of the pitfalls and challenges associated with nano-(Q)SARs in relation to the categorisation of nanomaterials. Our findings show clear gaps in the research framework that must be addressed if we are to have reliable predictions from such models. Three major barriers were identified: the need to improve quality of experimental data in which the models are developed from, the need to have practical guidelines for the development of the nano(Q)SAR models and the need to standardise and harmonise activities for the purpose of regulation. Of these three, the first, i.e. the need to improve data quality requires immediate attention, as it underpins activities associated with the latter two. It should be noted that the usefulness of data in the context of nano-(Q)SAR modelling is not only about the quantity of data but also about the quality, consistency and accessibility of those data. PMID:25211549

  15. Limited transmission of emergent H7N9 influenza A virus in a simulated live animal market: Do chickens pose the principal transmission threat?

    Science.gov (United States)

    Bosco-Lauth, Angela M; Bowen, Richard A; Root, J Jeffrey

    2016-08-01

    Emergent H7N9 influenza A virus has caused multiple public health and financial hardships. While some epidemiological studies have recognized infected chickens as an important bridge for human infections, the generality of this observation, the minimum infectious dose, and the shedding potential of chickens have received conflicting results. We experimentally tested the ability of domestic chickens (Gallus gallus domesticus) to transmit H7N9 to co-housed chickens and to several other animal species in an experimental live animal market. Results indicated that an infected chicken failed to initiate viral shedding of H7N9 to naïve co-housed chickens. The infected chicken did, however, successfully transmit the virus to quail (Coturnix sp.) located directly below the infected chicken cage. Oral shedding by indirectly infected quail was, on average, greater than ten-fold that of directly inoculated chickens. Best management practices in live animal market systems should consider the position of quail in stacked-cage settings. PMID:27236304

  16. Limited transmission of emergent H7N9 influenza A virus in a simulated live animal market: Do chickens pose the principal transmission threat?

    Science.gov (United States)

    Bosco-Lauth, Angela M; Bowen, Richard A; Root, J Jeffrey

    2016-08-01

    Emergent H7N9 influenza A virus has caused multiple public health and financial hardships. While some epidemiological studies have recognized infected chickens as an important bridge for human infections, the generality of this observation, the minimum infectious dose, and the shedding potential of chickens have received conflicting results. We experimentally tested the ability of domestic chickens (Gallus gallus domesticus) to transmit H7N9 to co-housed chickens and to several other animal species in an experimental live animal market. Results indicated that an infected chicken failed to initiate viral shedding of H7N9 to naïve co-housed chickens. The infected chicken did, however, successfully transmit the virus to quail (Coturnix sp.) located directly below the infected chicken cage. Oral shedding by indirectly infected quail was, on average, greater than ten-fold that of directly inoculated chickens. Best management practices in live animal market systems should consider the position of quail in stacked-cage settings.

  17. Bioinformatic Analysis of Putative Gene Products Encoded in SARS-HCoV Genome

    Institute of Scientific and Technical Information of China (English)

    赵心刚; 韩敬东; 宁元亨; 孟安明; 陈晔光

    2003-01-01

    The cause of severe acute respiratory syndrome (SARS) has been identified as a new coronavirus named as SARS-HCoV.Using bioinformatic methods, we have performed a detailed domain search.In addition to the viral structure proteins, we have found that several putative polypeptides share sequence similarity to known domains or proteins.This study may provide a basis for future studies on the infection and replication process of this notorious virus.

  18. THE MOLECULAR EVOLUTION OF THE MOST DANGEROUS EMERGING VIRUS INFECTIONS

    Directory of Open Access Journals (Sweden)

    Popov NN

    2016-03-01

    Full Text Available In this paper we reviewed what is known about the emerging viruses, the hosts that they originate in, and the molecular events that drive their emergence. When a pathogen crosses over from animals to humans, or an existing human disease suddenly increases in incidence, the infectious disease is said to be ‘emerging’. Most of the emerging pathogens originate from nonhuman animal species which has been termed natural reservoirs. The number of emerging infectious diseases has increased over the last few decades, driven by both anthropogenic and environmental factors such as population growth, urbanization, global travel and trade, intensification of livestock production. Now it has been believed that the emergence process may include four steps. On the first step the exposure of the humans to a novel virus occures. On the second step the subset of the viruses overcome the cross-species barrier. Host shifts have resulted in multiple human pandemics, such as HIV from chimps the H1N1, ‘‘spanish flu’’ from birds, SARS-CoV and virus Ebola from bats. Then some viruses enables to transmit from one human to another. And on the last step the viruses that are sufficiently transmissible between humans cause outbreaks and become endemic in human populations without the requirement of a natural reservoir. This review aims to discuss the molecular mechanisms that govern virus cross-species transmission and following stage, using the emergence of HIV, SARS-CoV, virus Ebola and influenza virus A as the models.Populations of many viruses harbour abundant genetic variability due to a combination of high mutation, recombination or reassortation rates and large population sizes. Mutations and recombinations has been associated with the increases in virulence, the evasion of host immunity and the evolution of resistance to antivirals. Genetic alterations in one species may results in the acquisition of variations that allow them to overcome cross species

  19. Human monoclonal antibody combination against SARS coronavirus: synergy and coverage of escape mutants.

    OpenAIRE

    Jan ter Meulen; van den Brink, Edward N; Poon, Leo L.M.; Wilfred E Marissen; Leung, Cynthia S. W; Freek Cox; Chung Y Cheung; Bakker, Arjen Q.; Johannes A Bogaards; Els van Deventer; Wolfgang Preiser; Hans Wilhelm Doerr; Chow, Vincent T.; John de Kruif; Peiris, Joseph S. M.

    2006-01-01

    Editors' Summary Background. Late in 2002, severe acute respiratory syndrome (SARS) emerged in the Guangdong province of China. In February 2003, an infected doctor from the province carried this new viral threat to human health to Hong Kong. Here, people staying in the same hotel caught the disease and took it to other countries. SARS was on the move, hitching lifts with international travellers. Because the virus responsible for SARS—SARS-CoV—spread by close person-to-person contact and kil...

  20. HCV感染动物模型的研究进展%New progress in development of animal models of hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    朱婷; 聂青和

    2015-01-01

    An animal model of hepatitis C virus (HCV)infection involves the use of an animal to build the model for simulating the whole process of HCV infection in humans.Establishing an ideal animal model for HCV infection is conducive to study on the pathogenesis of chro-nic hepatitis C,including virus-host interactions,viral variability,and host immune response patterns.Additionally,it provides a more ef-fective technical strategy for screening antiviral drugs and developing preventive vaccines.This article summarizes well-known animal mod-els of HCV infection,such as those established in chimpanzees,tree shrews,and mice.The advantages and drawbacks of each kind of ani-mal models are analyzed.In recent years,the establishment of small animal models,particularly those in transgenic mice,has opened up a new field in the development of animal models of HCV infection,which will be the hotspot and emphasis of relevant animal model studies.%理想的HCV感染动物模型的建立,不仅有利于研究慢性丙型肝炎的致病机制(包括病毒-宿主相互作用、病毒变异性、宿主免疫应答规律),还为抗病毒药物的筛选和预防性疫苗的研发提供了更有效的技术途径。介绍了目前大家熟知的动物模型,包括黑猩猩模型、树闙模型、小鼠模型等,并对各种模型的优势与缺陷进行了分析。近年来HCV感染小动物模型,尤其是转基因小鼠模型的建立,为HCV感染动物模型开创了新领域,是动物模型研究的热点和重点。

  1. IRES-mediated translation of foot-and-mouth disease virus (FMDV) in cultured cells derived from FMDV-susceptible and -insusceptible animals

    OpenAIRE

    Kanda, Takehiro; Ozawa, Makoto; Tsukiyama-Kohara, Kyoko

    2016-01-01

    Background Foot-and-mouth disease virus (FMDV) possess a positive sense, single stranded RNA genome. Internal ribosomal entry site (IRES) element exists within its 5′ untranslated region (5′UTR) of the viral RNA. Translation of the viral RNA is initiated by internal entry of the 40S ribosome within the IRES element. This process is facilitated by cellular factors known as IRES trans-acting factors (ITAFs). Foot-and-mouth disease (FMD) is host-restricted disease for cloven-hoofed animals such ...

  2. Elicitation of strong immune responses by a DNA vaccine expressing a secreted form of hepatitis C virus envelope protein E2 in murine and porcine animal models

    DEFF Research Database (Denmark)

    Li, Yiping; Kang, H.N.; Babiuk, L.A.;

    2006-01-01

    AIM: To characterize the immunogenicity of a hepatitis C virus (HCV) E2 DNA vaccine alone or with a protein vaccine boost in murine and porcine animal models. METHODS: A DNA vaccine expressing a secreted form of HCV E2 protein was constructed and used to vaccinate mice and piglets with or without...... boosting with a recombinant E2 protein vaccine formulated with CpG ODN and 10% Emulsigen. The immunogenicity of HCV E2 vaccines was analyzed by ELISA for antibody responses, MTT assay for lymphocyte proliferation, ELISPOT for the number of interferon-gamma secreting cells, and cytotoxic T lymphocyte assays...

  3. Humans, Other Animals and Disease: a comparative approach towards the development of a standardised recording protocol for animal palaeopathology

    Directory of Open Access Journals (Sweden)

    Stephanie Vann

    2006-11-01

    Full Text Available In recent years the impact of animal disease on human societies has had an extremely high profile, with the spread of diseases such as Bovine Spongiform Encephalopathy (BSE and foot and mouth among animal populations, as well as the transmission of diseases such as Human Immunodeficiency Virus (HIV, Ebola and Severe Acute Respiratory Syndrome (SARS from animal to human populations. The social and economic impact of such illnesses has been profound. However, studies on the effect of animal disease in past human populations have been widely neglected. This is partly due to the inconsistent manner in which instances of animal disease (palaeopathology are recorded, diagnosed and interpreted which, together with the typically low incidence of specimens per site, has precluded detailed studies of regional or temporal trends. This article outlines the archaeological rationale behind developing a generic methodology to enable the consistent recognition, recording and description of animal palaeopathological data. Furthermore, the experience of palaeopathologists concerned with human populations has been drawn upon to develop a downloadable, stand-alone recording system to facilitate the recording of animal palaeopathological data and enable questions concerning past animal health and disease to be better explored in future.

  4. Recovering Seasat SAR Data

    Science.gov (United States)

    Logan, T. A.; Arko, S. A.; Rosen, P. A.

    2013-12-01

    To demonstrate the feasibility of orbital remote sensing for global ocean observations, NASA launched Seasat on June 27th, 1978. Being the first space borne SAR mission, Seasat produced the most detailed SAR images of Earth from space ever seen to that point in time. While much of the data collected in the USA was processed optically, a mere 150 scenes had been digitally processed by March 1980. In fact, only an estimated 3% of Seasat data was ever digitally processed. Thus, for over three decades, the majority of the SAR data from this historic mission has been dormant, virtually unavailable to scientists in the 21st century. Over the last year, researchers at the Alaska Satellite Facility (ASF) Distributed Active Archive Center (DAAC) have processed the Seasat SAR archives into imagery products. A telemetry decoding system was created and the data were filtered into readily processable signal files. Due to nearly 35 years of bit rot, the bit error rate (BER) for the ASF DAAC Seasat archives was on the order of 1 out of 100 to 1 out of 100,000. This extremely high BER initially seemed to make much of the data undecodable - because the minor frame numbers are just 7 bits and no range line numbers exist in the telemetry even the 'simple' tasks of tracking the minor frame number or locating the start of each range line proved difficult. Eventually, using 5 frame numbers in sequence and a handful of heuristics, the data were successfully decoded into full range lines. Concurrently, all metadata were stored into external files. Recovery of this metadata was also problematic, the BER making the information highly suspect and, initially at least, unusable in any sort of automated fashion. Because of the BER, all of the single bit metadata fields proved unreliable. Even fields that should be constant for a data take (e.g. receiving station, day of the year) showed high variability, each requiring a median filter to be usable. The most challenging, however, were the

  5. Analytical SAR-GMTI principles

    Science.gov (United States)

    Soumekh, Mehrdad; Majumder, Uttam K.; Barnes, Christopher; Sobota, David; Minardi, Michael

    2016-05-01

    This paper provides analytical principles to relate the signature of a moving target to parameters in a SAR system. Our objective is to establish analytical tools that could predict the shift and smearing of a moving target in a subaperture SAR image. Hence, a user could identify the system parameters such as the coherent processing interval for a subaperture that is suitable to localize the signature of a moving target for detection, tracking and geolocating the moving target. The paper begins by outlining two well-known SAR data collection methods to detect moving targets. One uses a scanning beam in the azimuth domain with a relatively high PRF to separate the moving targets and the stationary background (clutter); this is also known as Doppler Beam Sharpening. The other scheme uses two receivers along the track to null the clutter and, thus, provide GMTI. We also present results on implementing our SAR-GMTI analytical principles for the anticipated shift and smearing of a moving target in a simulated code. The code would provide a tool for the user to change the SAR system and moving target parameters, and predict the properties of a moving target signature in a subaperture SAR image for a scene that is composed of both stationary and moving targets. Hence, the SAR simulation and imaging code could be used to demonstrate the validity and accuracy of the above analytical principles to predict the properties of a moving target signature in a subaperture SAR image.

  6. PHARUS : PHased ARray Universal SAR

    NARCIS (Netherlands)

    Paquay, M.H.A.; Vermeulen, B.C.B.; Koomen, P.J.; Hoogeboom, P.; Snoeij, P.; Pouwels, H.

    1996-01-01

    In the Netherlands, a polarimetric C-band aircraft SAR (Synthetic Aperture Radar) has been developed. The project is called PHARUS, an acronm for PHased ARray Universal SAR. This instrument serves remote sensing applications. The antenna system contains 48 active modules (expandable to 96). A module

  7. Demonstration MTI/SAR capability

    NARCIS (Netherlands)

    Vries, F.P.P. de; Broek, A.C. van den; Otten, M.P.G.; Groot, J.S.; Steeghs, T.P.H.; Dekker, R.J.; Rossum, W.L. van

    2001-01-01

    The aim of this project is to demonstrate to the Dutch armed forces the capability of MTI (Moving Target Indicator) and SAR (Synthetic Aperture Radar). This is done with the Dutch PHARUS sensor. The sensor is used to demonstrate how a phased array antenna can be used as an MTI/SAR sensor combination

  8. Excretion and detection of SARS coronavirus and its nucleic acid from digestive system

    Institute of Scientific and Technical Information of China (English)

    Xin-Wei Wang; Xiao-Ming Wu; Wen-Jun Xiao; Xiu-Mei Zhu; Chang-Qing Gu; Jing Yin; Wei Wei; Wei Yao; Chao Liu; Jian-Feng Li; Guo-Rong Ou; Jin-Song Li; Min-Nian Wang; Tong-Yu Fang; Gui-Jie Wang; Yao-Hui Qiu; Huai-Huan Wu; Fu-Huan Chao; Jun-Wen Li; Ting-Kai Guo; Bei Zhen; Qing-Xin Kong; Bin Yi; Zhong Li; Nong Song; Min Jin

    2005-01-01

    AIM: To study whether severe acute respiratory syndrome coronavirus (SARS-CoV) could be excreted from digestive system.METHODS: Cell culture and semi-nested RT-PCR were used to detect SARS-CoV and its RNA from 21 stool and urine samples, and a kind of electropositive filter media particles was used to concentrate the virus in 10 sewage samples from two hospitals receiving SAPS patients in Beijing in China.RESULTS: It was demonstrated that there was no live SARS-CoV in all samples collected, but the RNA of SARS-CoV could be detected in seven stool samples from SARS patients with any one of the symptoms of fever, malaise,cough, or dyspnea, in 10 sewage samples before disinfection and 3 samples after disinfection from the two hospitals.The RNA could not be detected in urine and stool samples from patients recovered from SARS.CONCLUSION: Nucleic acid of SARS-CoV can be excreted through the stool of patients into sewage system, and the possibility of SARS-CoV transmitting through digestive system cannot be excluded.

  9. Genome sequence variation analysis of two SARS coronavirus isolates after passage in Vero cell culture

    Institute of Scientific and Technical Information of China (English)

    JIN Weiwu; LI Ning; HU Liangxiang; DU Zhenglin; GAO Qiang; GAO Hong; NING Ye; FENG Jidong; ZHANG Jiansan; YIN Weidong

    2004-01-01

    SARS coronavirus is an RNA virus whose replication is error-prone, which provides possibility for escape of host defenses, and even leads to evolution of new viral strains during the passage or the transmission. Lots of variations have been detected among different SARS-CoV strains. And a study on these variations is helpful for development of efficient vaccine. Moreover, the test of nucleic acid characterization and genetic stability of SARS-CoV is important in the research of inactivated vaccine. The whole genome sequences of two SARS coronavirus strains after passage in Vero cell culture were determined and were compared with those of early passages, respectively. Results showed that both SARS coronavirus strains have high genetic stability, although nearly 10 generations were passed. Four nucleotide variations were observed between the second passage and the 11th passage of Sino1 strain for identification of SARS inactivated vaccine. Moreover, only one nucleotide was different between the third passage and the 10th passage of Sino3 strain for SARS inactivated vaccine. Therefore, this study suggested it was possible to develop inactivated vaccine against SARS-CoV in the future.

  10. SAR Altimetry Applications over Water

    CERN Document Server

    Martin-Puig, C; Ruffini, G; Raney, R K; Benveniste, J

    2008-01-01

    The application of Synthetic Aperture Radar (SAR) techniques to classical radar altimetry offers the potential for greatly improved Earth surface mapping. This paper provides an overview of the progress of SAMOSA, Development of SAR Altimetry Studies and Applications over Ocean, Coastal zones and Inland waters, an on-going ESA-funded project. The main objective of SAMOSA is to better quantify the improvement of SAR altimetry over conventional altimetry on water surfaces. More specifically, one of the tasks focuses on the reduction of SAR mode data to pulse-limited altimeter data, and a theoretical modelling to characterize the expected gain between high Pulse Repetition Frequency (PRF) reduced SAR mode data and low PRF classical Low-Resolution Mode (LRM) data. To this end, theoretical modelling using the Cramer-Rao bound (CRB) will be used and the results will be compared to previous theoretical estimates [7], using an analysis akin to that in [8].

  11. Bistatic SAR: Imagery & Image Products.

    Energy Technology Data Exchange (ETDEWEB)

    Yocky, David A.; Wahl, Daniel E.; Jakowatz, Charles V,

    2014-10-01

    While typical SAR imaging employs a co-located (monostatic) RADAR transmitter and receiver, bistatic SAR imaging separates the transmitter and receiver locations. The transmitter and receiver geometry determines if the scattered signal is back scatter, forward scatter, or side scatter. The monostatic SAR image is backscatter. Therefore, depending on the transmitter/receiver collection geometry, the captured imagery may be quite different that that sensed at the monostatic SAR. This document presents imagery and image products formed from captured signals during the validation stage of the bistatic SAR research. Image quality and image characteristics are discussed first. Then image products such as two-color multi-view (2CMV) and coherent change detection (CCD) are presented.

  12. 广西岭景镇某山村蝙蝠携带SARS样冠状病毒及狂犬病毒的调查研究%The Investigation of SARS-like Coronavirus and Rabies Virus in the Bats of a Village in Lin Jin Town GuangXi

    Institute of Scientific and Technical Information of China (English)

    李志峰; 俞守义; 吴毅

    2007-01-01

    目的 了解广西岭景镇某山村蝙蝠携带SARS样冠状病毒及狂犬病毒的情况.方法 对广西岭景镇某山村开展流行病学调查,捕捉蝙蝠,采集咽拭、肛拭及粪便标本,进行RT-PCR和细胞分离培养检测狂犬病毒(Rabies virus,RV)、SARS样冠状病毒(SARS-like Coronavirus,SARS-like-CoV).结果 本次调查收集了4只犬蝠(Cynopterus sphinx)、6只普氏蹄蝠(Hipposideros pratti,)和7只中菊头蝠(Rhinolophus affinis),在采集的标本中未检测到SARS样冠状病毒及狂犬病毒.结论 未发现调查的3种蝙蝠携带SARS样冠状病毒及狂犬病毒.

  13. Optimization of immunohistochemical and fluorescent antibody techniques for localization of foot-and-mouth disease virus in animal tissues

    Science.gov (United States)

    Immunohistochemical (IHC) and immunofluorescent (IF) techniques were optimized for the detection of foot-and-mouth disease virus (FMDV) structural and non-structural proteins in frozen and paraformaldehyde-fixed paraffin embedded (PFPE) tissues of bovine and porcine origin. Immunohistochemical local...

  14. [Bats and Viruses: complex relationships].

    Science.gov (United States)

    Rodhain, F

    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

  15. Comparison of immunocapture and RT-PCR techniques for the detection of peste-des-petits-ruminants virus (PPRV) in eye and nose swabs from infected animals

    International Nuclear Information System (INIS)

    Full text: Peste des Petits Ruminants (PPR) is a highly contagious disease of domestic and wild small ruminants. It constitutes a major constraint on production in areas where it is endemic. Classically, it is characterised by fever, nasal and ocular discharges, diarrhoea, respiratory distress, mucosal erosive lesions and death in 40-80% of acute cases. All these clinical signs, apart from the respiratory symptoms, are very similar to those of rinderpest (RP). The causal agents of both diseases are viruses which belong to the Morbillivirus genus. Described for the first time in 1942 in Cote d'Ivoire, PPR was considered for a long time as a disease of West African countries. The current knowledge on its epidemiology shows that this is no longer true, nor it is a solely African disease since it is widespread in countries lying between the Sahara and the Equator, in the Middle East and in South-West Asia. These data indicate that PPR existed undetected in most of the known endemic areas for a long time. It was overlooked because of the similarity of clinical signs to rinderpest as indicated above and also to pasteurellosis for the bronchopneumonia. The current knowledge of the disease has grown up quickly once specific diagnostic tests became available in the 1990's: serological diagnosis in the competitive format or for antigen detection by immunocapture cDNA probe and the amplification (RT-PCR) technique for the nucleic acid detection. While the immunocapture (ICE) can detect virus up to 100.6 TCID50 of virus in 50μl of sample, the limit of detection of the RT-PCR is estimated to 0.001 TCD50/ml. During a study to analyse the pathogenicity of some PPRV isolates, we have compared the efficiency of the ICE test, antibody-based antigen detection, and RT-PCR, with the RT-PCR, nucleic acid-based detection technique, to detect the shedding of the virus by the infected animals. For the study, Sahelian goats were inoculated IM with PPRV Guinea (isolate from Guinea Conakry

  16. Establishment of reverse transcription loop-mediated isothermal amplification for rapid detection and differentiation of canine distemper virus infected and vaccinated animals.

    Science.gov (United States)

    Liu, Da-Fei; Liu, Chun-Guo; Tian, Jin; Jiang, Yi-Tong; Zhang, Xiao-Zhan; Chai, Hong-Liang; Yang, Tian-Kuo; Yin, Xiu-Chen; Zhang, Hong-Ying; Liu, Ming; Hua, Yu-Ping; Qu, Lian-Dong

    2015-06-01

    Although widespread vaccination against canine distemper virus (CDV) has been conducted for many decades, several canine distemper outbreaks in vaccinated animals have been reported frequently. In order to detect and differentiate the wild-type and vaccine strains of the CDV from the vaccinated animals, a novel reverse transcription loop-mediated isothermal amplification (RT-LAMP) method was developed. A set of four primers-two internal and two external-were designed to target the H gene for the specific detection of wild-type CDV variants. The CDV-H RT-LAMP assay rapidly amplified the target gene, within 60 min, using a water bath held at a constant temperature of 65°C. The assay was 100-fold more sensitive than conventional RT-PCR, with a detection limit of 10(-1)TCID50ml(-1). The system showed a preference for wild-type CDV, and exhibited less sensitivity to canine parvovirus, canine adenovirus type 1 and type 2, canine coronavirus, and canine parainfluenza virus. The assay was validated using 102 clinical samples obtained from vaccinated dog farms, and the results were comparable to a multiplex nested RT-PCR assay. The specific CDV-H RT-LAMP assay provides a simple, rapid, and sensitive tool for the detection of canines infected with wild-type CDV from canines vaccinated with attenuated vaccine. PMID:25769803

  17. Anatomy of a SAR impulse response.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2007-08-01

    A principal measure of Synthetic Aperture Radar (SAR) image quality is the manifestation in the SAR image of a spatial impulse, that is, the SAR's Impulse Response (IPR). IPR requirements direct certain design decisions in a SAR. Anomalies in the IPR can point to specific anomalous behavior in the radar's hardware and/or software.

  18. High Resolution Processing with an Active Phased Array SAR

    NARCIS (Netherlands)

    Nijenboer, F.J.; Otten, M.P.G.

    1999-01-01

    The Dutch PHARUS system is a polarimetric active phased array SAR capable of performing advanced SAR modes. Advanced SAR modes that are being investigated are: spotlight SAR, sliding spotlight SAR, stepped frequency SAR and interferometric SAR. The flight experiments and automatic beam steering impl

  19. State-of-art of Geosynchronous SAR

    Institute of Scientific and Technical Information of China (English)

    MAO Er-ke; LONG Teng; ZENG Tao; HU Cheng; TIAN Ye

    2012-01-01

    Geosynchronous Earth Orbit Synthetic Aperture Radar (GEO SAR) runs in the height of 360000Km geosynchronous earth orbit,compared with traditional Low Earth Orbit (LEO) SAR (orbit height under 1000Km),GEO SAR has advantages of shorter repeat period,wider swath and so on.Firstly,the basic principle and state-of-art of GEO SAR in domestic and overseas are introduced.Secondly,coverage characteristic of GEO SAR is analyzed.Thirdly,the key problems of yaw steering and imaging on curved trajectory in GEO SAR are discussed in detail,and the corresponding primary solutions are presented in order to promote future research on GEO SAR.

  20. The SARS-unique domain (SUD of SARS coronavirus contains two macrodomains that bind G-quadruplexes.

    Directory of Open Access Journals (Sweden)

    Jinzhi Tan

    2009-05-01

    Full Text Available Since the outbreak of severe acute respiratory syndrome (SARS in 2003, the three-dimensional structures of several of the replicase/transcriptase components of SARS coronavirus (SARS-CoV, the non-structural proteins (Nsps, have been determined. However, within the large Nsp3 (1922 amino-acid residues, the structure and function of the so-called SARS-unique domain (SUD have remained elusive. SUD occurs only in SARS-CoV and the highly related viruses found in certain bats, but is absent from all other coronaviruses. Therefore, it has been speculated that it may be involved in the extreme pathogenicity of SARS-CoV, compared to other coronaviruses, most of which cause only mild infections in humans. In order to help elucidate the function of the SUD, we have determined crystal structures of fragment 389-652 ("SUD(core" of Nsp3, which comprises 264 of the 338 residues of the domain. Both the monoclinic and triclinic crystal forms (2.2 and 2.8 A resolution, respectively revealed that SUD(core forms a homodimer. Each monomer consists of two subdomains, SUD-N and SUD-M, with a macrodomain fold similar to the SARS-CoV X-domain. However, in contrast to the latter, SUD fails to bind ADP-ribose, as determined by zone-interference gel electrophoresis. Instead, the entire SUD(core as well as its individual subdomains interact with oligonucleotides known to form G-quadruplexes. This includes oligodeoxy- as well as oligoribonucleotides. Mutations of selected lysine residues on the surface of the SUD-N subdomain lead to reduction of G-quadruplex binding, whereas mutations in the SUD-M subdomain abolish it. As there is no evidence for Nsp3 entering the nucleus of the host cell, the SARS-CoV genomic RNA or host-cell mRNA containing long G-stretches may be targets of SUD. The SARS-CoV genome is devoid of G-stretches longer than 5-6 nucleotides, but more extended G-stretches are found in the 3'-nontranslated regions of mRNAs coding for certain host-cell proteins

  1. DEM FROM SAR:PRINCIPLE AND APPLICATION

    Institute of Scientific and Technical Information of China (English)

    Li Deren; Yang Jie

    2003-01-01

    The paper gives an overview of the principle and application of generating DEM from SAR, including the principle and processing flow of generating DEM from single SAR and SAR interferometry. Afterwards, the application fields of InSAR for terrain surveying, volcanic terrain surveying and D-InSAR for monitoring ground subsiding are listed and described as well.The problem and prospect of application are also pointed out in the last part of this paper.

  2. Synthetic Aperture Radar (SAR) data processing

    Science.gov (United States)

    Beckner, F. L.; Ahr, H. A.; Ausherman, D. A.; Cutrona, L. J.; Francisco, S.; Harrison, R. E.; Heuser, J. S.; Jordan, R. L.; Justus, J.; Manning, B.

    1978-01-01

    The available and optimal methods for generating SAR imagery for NASA applications were identified. The SAR image quality and data processing requirements associated with these applications were studied. Mathematical operations and algorithms required to process sensor data into SAR imagery were defined. The architecture of SAR image formation processors was discussed, and technology necessary to implement the SAR data processors used in both general purpose and dedicated imaging systems was addressed.

  3. Differential cell line susceptibility to the emerging Zika virus: implications for disease pathogenesis, non-vector-borne human transmission and animal reservoirs

    Science.gov (United States)

    Chan, Jasper Fuk-Woo; Yip, Cyril Chik-Yan; Tsang, Jessica Oi-Ling; Tee, Kah-Meng; Cai, Jian-Piao; Chik, Kenn Ka-Heng; Zhu, Zheng; Chan, Chris Chung-Sing; Choi, Garnet Kwan-Yue; Sridhar, Siddharth; Zhang, Anna Jinxia; Lu, Gang; Chiu, Kin; Lo, Amy Cheuk-Yin; Tsao, Sai-Wah; Kok, Kin-Hang; Jin, Dong-Yan; Chan, Kwok-Hung; Yuen, Kwok-Yung

    2016-01-01

    Zika virus (ZIKV) is unique among human-pathogenic flaviviruses by its association with congenital anomalies and trans-placental and sexual human-to-human transmission. Although the pathogenesis of ZIKV-associated neurological complications has been reported in recent studies, key questions on the pathogenesis of the other clinical manifestations, non-vector-borne transmission and potential animal reservoirs of ZIKV remain unanswered. We systematically characterized the differential cell line susceptibility of 18 human and 15 nonhuman cell lines to two ZIKV isolates (human and primate) and dengue virus type 2 (DENV-2). Productive ZIKV replication (⩾2 log increase in viral load, ZIKV nonstructural protein-1 (NS1) protein expression and cytopathic effects (CPE)) was found in the placental (JEG-3), neuronal (SF268), muscle (RD), retinal (ARPE19), pulmonary (Hep-2 and HFL), colonic (Caco-2),and hepatic (Huh-7) cell lines. These findings helped to explain the trans-placental transmission and other clinical manifestations of ZIKV. Notably, the prostatic (LNCaP), testicular (833KE) and renal (HEK) cell lines showed increased ZIKV load and/or NS1 protein expression without inducing CPE, suggesting their potential roles in sexual transmission with persistent viral replication at these anatomical sites. Comparatively, none of the placental and genital tract cell lines allowed efficient DENV-2 replication. Among the nonhuman cell lines, nonhuman primate (Vero and LLC-MK2), pig (PK-15), rabbit (RK-13), hamster (BHK21) and chicken (DF-1) cell lines supported productive ZIKV replication. These animal species may be important reservoirs and/or potential animal models for ZIKV. The findings in our study help to explain the viral shedding pattern, transmission and pathogenesis of the rapidly disseminating ZIKV, and are useful for optimizing laboratory diagnostics and studies on the pathogenesis and counter-measures of ZIKV. PMID:27553173

  4. Differential cell line susceptibility to the emerging Zika virus: implications for disease pathogenesis, non-vector-borne human transmission and animal reservoirs.

    Science.gov (United States)

    Chan, Jasper Fuk-Woo; Yip, Cyril Chik-Yan; Tsang, Jessica Oi-Ling; Tee, Kah-Meng; Cai, Jian-Piao; Chik, Kenn Ka-Heng; Zhu, Zheng; Chan, Chris Chung-Sing; Choi, Garnet Kwan-Yue; Sridhar, Siddharth; Zhang, Anna Jinxia; Lu, Gang; Chiu, Kin; Lo, Amy Cheuk-Yin; Tsao, Sai-Wah; Kok, Kin-Hang; Jin, Dong-Yan; Chan, Kwok-Hung; Yuen, Kwok-Yung

    2016-01-01

    Zika virus (ZIKV) is unique among human-pathogenic flaviviruses by its association with congenital anomalies and trans-placental and sexual human-to-human transmission. Although the pathogenesis of ZIKV-associated neurological complications has been reported in recent studies, key questions on the pathogenesis of the other clinical manifestations, non-vector-borne transmission and potential animal reservoirs of ZIKV remain unanswered. We systematically characterized the differential cell line susceptibility of 18 human and 15 nonhuman cell lines to two ZIKV isolates (human and primate) and dengue virus type 2 (DENV-2). Productive ZIKV replication (⩾2 log increase in viral load, ZIKV nonstructural protein-1 (NS1) protein expression and cytopathic effects (CPE)) was found in the placental (JEG-3), neuronal (SF268), muscle (RD), retinal (ARPE19), pulmonary (Hep-2 and HFL), colonic (Caco-2),and hepatic (Huh-7) cell lines. These findings helped to explain the trans-placental transmission and other clinical manifestations of ZIKV. Notably, the prostatic (LNCaP), testicular (833KE) and renal (HEK) cell lines showed increased ZIKV load and/or NS1 protein expression without inducing CPE, suggesting their potential roles in sexual transmission with persistent viral replication at these anatomical sites. Comparatively, none of the placental and genital tract cell lines allowed efficient DENV-2 replication. Among the nonhuman cell lines, nonhuman primate (Vero and LLC-MK2), pig (PK-15), rabbit (RK-13), hamster (BHK21) and chicken (DF-1) cell lines supported productive ZIKV replication. These animal species may be important reservoirs and/or potential animal models for ZIKV. The findings in our study help to explain the viral shedding pattern, transmission and pathogenesis of the rapidly disseminating ZIKV, and are useful for optimizing laboratory diagnostics and studies on the pathogenesis and counter-measures of ZIKV. PMID:27553173

  5. SAR/InSAR observation by an HF sounder

    Science.gov (United States)

    Kobayashi, T.; Ono, T.

    2007-03-01

    Application of SAR imaging algorithm to spaceborne HF sounder observation was studied. Two types of image ambiguity problems were addressed in the application. One is surface/subsurface image ambiguity arising from deep penetration of HF wave, and another is mirror image ambiguity that is inherent to dipole antenna SAR. A numerical model demonstrated that the surface/subsurface ambiguity can be mitigated by taking a synthetic aperture large enough to defocus subsurface objects. In order to resolve the mirror image ambiguity problem, an image superposition technique was proposed. The performance of the technique was demonstrated by using simulation data of the HF sounder observation to confirm the feasibility of HF SAR and HF InSAR observation.

  6. Novel avian-origin influenza A (H7N9) virus attachment to the respiratory tract of five animal models

    NARCIS (Netherlands)

    J.Y. Siegers (Jurre); K.R. Short (Kirsty); L.M.E. Leijten (Lonneke); M.T. de Graaf (Marieke); M.I. Spronken (Monique); E.J.A. Schrauwen (Eefje); N. Marshall (Nicolle); A.C. Lowen (Anice); G. Gabriel (Gülsah); A.D.M.E. Osterhaus (Albert); T. Kuiken (Thijs); D.A.J. van Riel (Debby)

    2014-01-01

    textabstractWe determined the pattern of attachment of the avian-origin H7N9 influenza viruses A/Anhui/1/2013 and A/Shanghai/1/2013 to the respiratory tract in ferrets, macaques, mice, pigs, and guinea pigs and compared it to that in humans. The H7N9 attachment pattern in macaques, mice, and to a le

  7. Identification of SARS-like coronaviruses in horseshoe bats (Rhinolophus hipposideros) in Slovenia.

    Science.gov (United States)

    Rihtaric, Danijela; Hostnik, Peter; Steyer, Andrej; Grom, Joze; Toplak, Ivan

    2010-04-01

    Bats have been identified as a natural reservoir for an increasing number of emerging zoonotic viruses, such as Hendra virus, Nipah virus, Ebola virus, Marburg virus, rabies and other lyssaviruses. Recently, a large number of viruses closely related to members of the genus Coronavirus have been associated with severe acute respiratory syndrome (SARS) and detected in bat species. In this study, samples were collected from 106 live bats of seven different bat species from 27 different locations in Slovenia. Coronaviruses were detected by RT-PCR in 14 out of 36 horseshoe bat (Rhinolophus hipposideros) fecal samples, with 38.8% virus prevalence. Sequence analysis of a 405-nucleotide region of the highly conserved RNA polymerase gene (pol) showed that all coronaviruses detected in this study are genetically closely related, with 99.5-100% nucleotide identity, and belong to group 2 of the coronaviruses. The most closely related virus sequence in GenBank was SARS bat isolate Rp3/2004 (DQ071615) within the SARS-like CoV cluster, sharing 85% nucleotide identity and 95.6% amino acid identity. The potential risk of a new group of bat coronaviruses as a reservoir for human infections is highly suspected, and further molecular epidemiologic studies of these bat coronaviruses are needed. PMID:20217155

  8. Swine and rabbits are the main reservoirs of hepatitis E virus in China: detection of HEV RNA in feces of farmed and wild animals.

    Science.gov (United States)

    Xia, Junke; Zeng, Hang; Liu, Lin; Zhang, Yulin; Liu, Peng; Geng, Jiabao; Wang, Lin; Wang, Ling; Zhuang, Hui

    2015-11-01

    Hepatitis E virus (HEV) infection is recognized as a zoonosis. The prevalence of HEV RNA and anti-HEV antibodies in many animal species has been reported, but the host range of HEV is unclear. The aims of this study were to investigate HEV infection in various animal species and to determine the reservoirs of HEV. Eight hundred twenty-two fecal samples from 17 mammal species and 67 fecal samples from 24 avian species were collected in China and tested for HEV RNA by RT-nPCR. The products of PCR were sequenced and analyzed phylogenetically. The positive rates of HEV RNA isolated from pigs in Beijing, Shandong, and Henan were 33%, 30%, and 92%, respectively, and that from rabbits in Beijing was 5%. HEV RNA was not detectable in farmed foxes, sheep or sika deer, or in wild animals in zoos, including wild boars, yaks, camels, Asiatic black bears, African lions, red pandas, civets, wolves, jackals and primates. Sequence analysis revealed that swine isolates had 97.8%-98.4% nucleotide sequence identity to genotype 4d isolates from patients in Shandong and Jiangsu of China. Phylogenetic analysis showed that swine HEV isolates belong to genotype 4, including subgenotype 4h in Henan and 4d in Beijing and Shandong. The rabbit HEV strains shared 93%-99% nucleotide sequence identity with rabbit strains isolated from Inner Mongolia. In conclusion, swine and rabbits have been confirmed to be the main reservoirs of HEV in China.

  9. TerraSAR-X mission

    Science.gov (United States)

    Werninghaus, Rolf

    2004-01-01

    The TerraSAR-X is a German national SAR- satellite system for scientific and commercial applications. It is the continuation of the scientifically and technologically successful radar missions X-SAR (1994) and SRTM (2000) and will bring the national technology developments DESA and TOPAS into operational use. The space segment of TerraSAR-X is an advanced high-resolution X-Band radar satellite. The system design is based on a sound market analysis performed by Infoterra. The TerraSAR-X features an advanced high-resolution X-Band Synthetic Aperture Radar based on the active phased array technology which allows the operation in Spotlight-, Stripmap- and ScanSAR Mode with various polarizations. It combines the ability to acquire high resolution images for detailed analysis as well as wide swath images for overview applications. In addition, experimental modes like the Dual Receive Antenna Mode allow for full-polarimetric imaging as well as along track interferometry, i.e. moving target identification. The Ground Segment is optimized for flexible response to (scientific and commercial) User requests and fast image product turn-around times. The TerraSAR-X mission will serve two main goals. The first goal is to provide the strongly supportive scientific community with multi-mode X-Band SAR data. The broad spectrum of scientific application areas include Hydrology, Geology, Climatology, Oceanography, Environmental Monitoring and Disaster Monitoring as well as Cartography (DEM Generation) and Interferometry. The second goal is the establishment of a commercial EO-market in Europe which is driven by Infoterra. The commercial goal is the development of a sustainable EO-business so that the e.g. follow-on systems can be completely financed by industry from the profit. Due to its commercial potential, the TerraSAR-X project will be implemented based on a public-private partnership with the Astrium GmbH. This paper will describe first the mission objectives as well as the

  10. Statistical Unmixing of SAR Images

    OpenAIRE

    Anfinsen, Stian Normann

    2016-01-01

    A method is presented which uses logarithmic statistics to detect and characterise class mixtures and targets in background clutter in synthetic aperture radar (SAR) images. Mixtures of ground cover types show up as extreme radar texture in statistical analysis of SAR images. Instead of modelling this as a spatially nonstationary radar cross section, this paper demonstrates how a mixture model analysis can be used to characterise the separate components and estimate their mixing proportions.

  11. Immunology of Bats and Their Viruses: Challenges and Opportunities

    OpenAIRE

    Tony Schountz

    2014-01-01

    Bats are reservoir hosts of several high-impact viruses that cause significant human diseases, including Nipah virus, Marburg virus and rabies virus. They also harbor many other viruses that are thought to have caused disease in humans after spillover into intermediate hosts, including SARS and MERS coronaviruses. As is usual with reservoir hosts, these viruses apparently cause little or no pathology in bats. Despite the importance of bats as reservoir hosts of zoonotic and potentially zoonot...

  12. Antigen Production in Plant to Tackle Infectious Diseases Flare Up: The Case of SARS.

    Science.gov (United States)

    Demurtas, Olivia C; Massa, Silvia; Illiano, Elena; De Martinis, Domenico; Chan, Paul K S; Di Bonito, Paola; Franconi, Rosella

    2016-01-01

    Severe acute respiratory syndrome (SARS) is a dangerous infection with pandemic potential. It emerged in 2002 and its aetiological agent, the SARS Coronavirus (SARS-CoV), crossed the species barrier to infect humans, showing high morbidity and mortality rates. No vaccines are currently licensed for SARS-CoV and important efforts have been performed during the first outbreak to develop diagnostic tools. Here we demonstrate the transient expression in Nicotiana benthamiana of two important antigenic determinants of the SARS-CoV, the nucleocapsid protein (N) and the membrane protein (M) using a virus-derived vector or agro-infiltration, respectively. For the M protein, this is the first description of production in plants, while for plant-derived N protein we demonstrate that it is recognized by sera of patients from the SARS outbreak in Hong Kong in 2003. The availability of recombinant N and M proteins from plants opens the way to further evaluation of their potential utility for the development of diagnostic and protection/therapy tools to be quickly manufactured, at low cost and with minimal risk, to face potential new highly infectious SARS-CoV outbreaks. PMID:26904039

  13. 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

  14. Differentiation of infected and vaccinated animals (DIVA) using the NS1 protein of avian influenza virus in chickens

    Science.gov (United States)

    The use of avian influenza (AI) vaccination in poultry would have greater world-wide acceptance if a reliable test that clearly discriminates naturally infected from vaccinated only animals (DIVA) was available. Because the non-structural protein (NS1) is expressed in infected cells, and is not pac...

  15. Viremia and antibody response of small African and laboratory animals to Crimean-Congo hemorrhagic fever virus infection.

    Science.gov (United States)

    Shepherd, A J; Leman, P A; Swanepoel, R

    1989-05-01

    Eleven species of small African wild mammals, laboratory rabbits, guinea pigs, and Syrian hamsters were infected with Crimean-Congo hemorrhagic fever (CCHF) virus. Low-titered viremia followed by development of antibody was observed in scrub hares (Lepus saxatilis), Cape ground squirrels (Xerus inauris), red veld rats (Aethomys chrysophilus), white tailed rats (Mystromys albicaudatus), bushveld gerbils (Tatera leucogaster), striped mice (Rhabdomys pumilio), and guinea pigs. The maximum viremic titer in 4 scrub hares was 10(1.7-4.2) 50% mouse lethal doses/ml. Viremia was detected in 1/17 infected laboratory rabbits. Antibody response was only detected in South African hedgehogs (Atelerix frontalis), highveld gerbils (T. brantsii), Namaqua gerbils (Desmodillus auricularis), 2 species of multimammate mouse (Mastomys natalensis and M. coucha), and Syrian hamsters. The results of the study indicate that a proportion of infected scrub hares develop CCHF viremia of an intensity shown in the Soviet Union to be sufficient for infection of feeding immature ixodid ticks, but that South African hedgehogs and wild rodents are unlikely to be of importance as maintenance hosts of the virus in southern Africa. PMID:2499205

  16. Development of a SARS Coronavirus Vaccine from Recombinant Spike Protein Plus Delta Inulin Adjuvant.

    Science.gov (United States)

    McPherson, Clifton; Chubet, Richard; Holtz, Kathy; Honda-Okubo, Yoshikazu; Barnard, Dale; Cox, Manon; Petrovsky, Nikolai

    2016-01-01

    Given periodic outbreaks of fatal human infections caused by coronaviruses, development of an optimal coronavirus vaccine platform capable of rapid production is an ongoing priority. This chapter describes the use of an insect cell expression system for rapid production of a recombinant vaccine against severe acute respiratory syndrome coronavirus (SARS). Detailed methods are presented for expression, purification, and release testing of SARS recombinant spike protein antigen, followed by adjuvant formulation and animal testing. The methods herein described for rapid development of a highly protective SARS vaccine are equally suited to rapid development of vaccines against other fatal human coronavirus infections, e.g., the MERS coronavirus.

  17. Energy metabolic disorder is a major risk factor in severe influenza virus infection: Proposals for new therapeutic options based on animal model experiments.

    Science.gov (United States)

    Kido, Hiroshi; Indalao, Irene L; Kim, Hyejin; Kimoto, Takashi; Sakai, Satoko; Takahashi, Etsuhisa

    2016-09-01

    Severe influenza is characterized by cytokine storm and multiorgan failure. Influenza patients with underlying diseases show a rapid progression in disease severity. The major mechanism that underlies multiorgan failure during the progressive stage of infection, particularly in patients with underlying risk factors, is mitochondrial energy crisis. The relationship between the factors that determine infection severity, such as influenza virus, cytokines, cellular trypsin as a hemagglutinin processing protease for viral multiplication, accumulation of metabolic intermediates and ATP crisis in mitochondria, is termed the "influenza virus-cytokine-trypsin" cycle. This occurs during the initial stages of infection, and is interconnected with the "metabolic disorders-cytokine" cycle in the middle to late phase of infection. Experiments using animal models have highlighted the complex relationship between these two cycles. New treatment options have been proposed that target the ATP crisis and multiorgan failure during the late phase of infection, rather than antiviral treatments with neuraminidase inhibitors that work during the initial phase. These options are (i) restoration of glucose oxidation in mitochondria by diisopropylamine dichloroacetate, which inhibits infection-induced pyruvate dehydrogenase kinase 4 activity, and (ii) restoration of long-chain fatty acid oxidation in mitochondria by l-carnitine and bezafibrate, an agonist of peroxisome proliferation-activated receptors-β/δ, which transcriptionally upregulates carnitine palmitoyltransferase II. The latter is particularly effective in patients with influenza-associated encephalopathy who have thermolabile and short half-life compound variants of carnitine palmitoyltransferase II. PMID:27566378

  18. 靶向SARS-CoV spike中和抗体的检测%Targeting SARS-CoV spike neutralizing antibody test

    Institute of Scientific and Technical Information of China (English)

    马萍; 杨宁; 郎建设; 蒋澄宇

    2012-01-01

    目的 建立靶向SARS-CoV spike中和抗体的检测模型.方法 构建优化的全基因SARS-CoV spike质粒免疫小鼠产生S1190抗血清,与合成的结合受体ACE2的S318-510蛋白进行作用,通过荧光显微镜观察对SARS假病毒感染抑制作用的变化以确证中和抗体的高效性.结果 SARS-CoV spike质粒诱导产生的S蛋白全长抗血清不但可以有效中和SARS假病毒进入HEK293E/ACE2-Myc细胞,S318-510蛋白的预处理可以降低抗血清对SARS假病毒的进入抑制效应.结论 受体结合部(RBD)的S318-510蛋白靶向SARS-CoV spike中和抗体的检测模型得到有效的验证.可以作为直观迅速判断中和抗体是否高效的模型推广至不具备P3级别的实验室.%Objective To establish a targeting SARS-CoV spike neutralizing antibody test model. Methods Construction of optimal whole SARS-CoV spike gene plasmid to induce mouse neutralizing antibody. Pretreatment with S318-510 protein targeting ACE2 to observe the inhibition change of SARS-CoV S pseudoviruses infection process via fluorescence microscope. Results _ SARS-CoV SI 190 Abs prevented SARS-CoV pseudovirus entry into HEK293E/ACE2-Myc cells and pretreatment with S318-510 inhibited neutralization of SARS-S entry antiserum. Conclusions This test model confirmation of SARS-CoV RBD targeting SARS-CoV spike neutralizing antibody may function as a test model of lethal viruses in laboratory not equiped as biosafety level 3.

  19. 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.

  20. Perspectives for future SAR Antenna Developement

    OpenAIRE

    Keydel, Wolfgang

    2007-01-01

    Goal of the paper is to present the expected development of future antennas for space borne SAR based on the state-of-the-art and to point out under that aspect some perspectives and visions for future space borne SAR systems. Future space borne SAR systems will consist mainly of the antenna with a small number of peripheral elements only, like solar cells, GPS, power supply, downlink equipment etc.. The present spaceborne SAR Antenna will mutate to a complete Antenna SAR that means a SAR...

  1. Comparative phylogenetic analysis of Dobrava-Belgrade virus L and S genetic segments isolated from an animal reservoir in Serbia

    Directory of Open Access Journals (Sweden)

    Nikolić Valentina

    2014-01-01

    Full Text Available The Dobrava-Belgrade virus (DOBV is a member of the Bunyaviridae family, genus Hantavirus, possessing a single-stranded RNA genome consisting of three segments, designated L (large, M (medium and S (small. In this study, we present phylogenetic analysis of a newly detected DOBV strain isolated from Apodemus agrarius. Analysis was based on partial L and S segment sequences, in comparison to previously published DOBV sequences from Serbia and elsewhere. A phylogenetic tree based on partial S segment revealed local geographical clustering of DOBV sequences from Serbia, unrelated to host (rodent or human. The topology of the phylogenetic tree was confirmed with a high percent of completely or partially resolved quartets in likelihood-mapping analysis, whereas no evidence of possible recombination in the examined S segment data set was found.

  2. Staphylococcus aureus sarA regulates inflammation and colonization during central nervous system biofilm formation.

    Directory of Open Access Journals (Sweden)

    Jessica N Snowden

    Full Text Available Infection is a frequent and serious complication following the treatment of hydrocephalus with CSF shunts, with limited therapeutic options because of biofilm formation along the catheter surface. Here we evaluated the possibility that the sarA regulatory locus engenders S. aureus more resistant to immune recognition in the central nervous system (CNS based on its reported ability to regulate biofilm formation. We utilized our established model of CNS catheter-associated infection, similar to CSF shunt infections seen in humans, to compare the kinetics of bacterial titers, cytokine production and inflammatory cell influx elicited by wild type S. aureus versus an isogenic sarA mutant. The sarA mutant was more rapidly cleared from infected catheters compared to its isogenic wild type strain. Consistent with this finding, several pro-inflammatory cytokines and chemokines, including IL-17, CXCL1, and IL-1β were significantly increased in the brain following infection with the sarA mutant versus wild type S. aureus, in agreement with the fact that the sarA mutant displayed impaired biofilm growth and favored a planktonic state. Neutrophil influx into the infected hemisphere was also increased in the animals infected with the sarA mutant compared to wild type bacteria. These changes were not attributable to extracellular protease activity, which is increased in the context of SarA mutation, since similar responses were observed between sarA and a sarA/protease mutant. Overall, these results demonstrate that sarA plays an important role in attenuating the inflammatory response during staphylococcal biofilm infection in the CNS via a mechanism that remains to be determined.

  3. Questionnaire survey about the motives of commercial livestock farmers and hobby holders to vaccinate their animals against Bluetongue virus serotype 8 in 2008-2009 in the Netherlands.

    Science.gov (United States)

    Elbers, A R W; de Koeijer, A A; Scolamacchia, F; van Rijn, P A

    2010-03-16

    After a massive epidemic of Bluetongue virus serotype 8 (BTV-8) among ruminants in 2006-2007 in the European Union (EU), the Netherlands started a voluntary emergency vaccination campaign in May 2008, subsidized by the EU. At the start of a new campaign in 2009, without subsidized vaccination, we investigated by mail survey the motives of farmers and hobby holders to vaccinate against BTV-8 in 2008 and 2009. Mean vaccine uptake in 2008 was: 73% in sheep, 71% in cattle, 43% in goat farms and 67% in hobby holdings. Top-5 motives pro-vaccination were: prevention of production loss; subsidized vaccination; recommendation by practitioner; welfare reasons; contribution to the eradication campaign. Top-5 motives against vaccination were: vaccination costs; absence of clinical BT-problems; presumed low infection risk; balance between vaccination costs and loss without vaccination; bad experience with earlier vaccination campaigns. Willingness to vaccinate was significantly lower in 2009: 42% in sheep, 58% in cattle, 19% in goat farms and 49% in hobby holdings. Measures to stimulate vaccination among those that did not want to vaccinate in 2009 were: subsidized vaccination; possibility to vaccinate their own animals; more information on efficacy/safety of vaccine and why animals had to be vaccinated again; availability of a BT vaccine combined with vaccine(s) against other diseases.

  4. Evaluation of the health, performance and economic effects on the general population from exposure to bovine viral diarrhea virus from persistently infected animals in the starter phase of the feedlot

    Science.gov (United States)

    The objective of this research was to evaluate the effects on health and performance in beef cattle resulting from exposure to bovine viral diarrhea virus (BVDV) persistently infected (PI) animals in a commercial feedlot. The study focused on economic effects associated with PI exposure during the ...

  5. Novel Polarimetric SAR Interferometry Algorithms Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Polarimetric radar interferometry (PolInSAR) is a new SAR imaging mode that is rapidly becoming an important technique for bare earth topographic mapping, tree...

  6. Accelerated Scientific InSAR Processing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Neva Ridge Technologies proposes to develop a suite of software tools for the analysis of SAR and InSAR data, focused on having a robust and adopted capability well...

  7. SAR Image Enhancement using Particle Filters

    Data.gov (United States)

    National Aeronautics and Space Administration — In this paper, we propose a novel approach to reduce the noise in Synthetic Aperture Radar (SAR) images using particle filters. Interpretation of SAR images is a...

  8. SARS Patients and Their Close Contacts

    Science.gov (United States)

    ... Laboratory Testing & Specimens SARS-Associated Coronavirus (SARS-CoV) Sequencing Informed Consent for Laboratory Testing Specimen Collection and ... person touches a surface or object contaminated with infectious droplets and then touches his or her mouth, ...

  9. Nano(Q)SAR: Challenges, pitfalls and perspectives

    OpenAIRE

    Tantra, R; Oksel, C; Puzyn, T; Wang, J; Robinson, KN; Wang, XZ; Ma, CY; Wilkins, T

    2015-01-01

    Regulation for nanomaterials is urgently needed, and the drive to adopt an intelligent testing strategy is evident. Such a strategy will not only provide economic benefits but will also reduce moral and ethical concerns arising from animal testing. For regulatory purposes, such an approach is promoted by REACH, particularly the use of quantitative structure–activity relationships [(Q)SAR] as a tool for the categorisation of compounds according to their physicochemical and toxicological proper...

  10. Comparison of Three ELISA Kits for the Differentiation of Foot-and-mouth Disease Virus-infected from Vaccinated Animals

    Institute of Scientific and Technical Information of China (English)

    Yi-mei CAO; Zeng-jun LU; Zai-xin LIU; Qing-ge XIE

    2007-01-01

    A study was performed to validate 3 FMDV 3ABC-I-ELISA kits developed in China for the differentiation of FMDV infected and vaccinated animals.Sets of sera from naive and vaccinated cattle as well as from cattle that had been infected were tested for antibodies against nonstructural proteins (NSPs) of FMDV by commercial diagnosis kits,Ceditest(R)FMDV-NS (Ceditest(R) kit),UBI(R) FMDV NONSTRUCTURAL PROTEIN ELISA DIRECTION INSERT (UBI(R) kit) and a FMDV 3ABC-I-ELISA kitdeveloped at the Lanzhou Veterinary Research Institute.The test parameters (sensitivity and specificity) of the three kits were determined,and the result obtained from FMD 3ABC-I-ELISA kit was compared with that obtained from two foreign kits.The results indicated that the coincidence rate between the FMDV 3ABC-I-ELISA and Ceditest(R) kits was 98.05%,and the coincidence rate between the FMDV 3ABC-I-ELISA and UBI(R) kits was 94.4%; the sensitivity of both Ceditest(R) and FMDV 3ABC-I-ELISA kit was 100%.However,the sensitivity of the UBI(R) kit was only 81.8%.With sera from naive or vaccinated non-infected animals,the specificity of all tests exceeded 90%.

  11. Urban Change Detection Using Multitemporal SAR Images

    OpenAIRE

    Yousif, Osama

    2015-01-01

    Multitemporal SAR images have been increasingly used for the detection of different types of environmental changes. The detection of urban changes using SAR images is complicated due to the complex mixture of the urban environment and the special characteristics of SAR images, for example, the existence of speckle. This thesis investigates urban change detection using multitemporal SAR images with the following specific objectives: (1) to investigate unsupervised change detection, (2) to inve...

  12. Change Detection Using Multitemporal SAR Images

    OpenAIRE

    Yousif, Osama

    2013-01-01

    Multitemporal SAR images have been used successfully for the detection of different types of environmental changes. The detection of urban change using SAR images is complicated due to the special characteristics of SAR images—for example, the existence of speckle and the complex mixture of the urban environment. This thesis investigates the detection of urban changes using SAR images with the following specific objectives: (1) to investigate unsupervised change detection, (2) to investigate ...

  13. End-organ protection in hypertension by the novel and selective Rho-kinase inhibitor, SAR407899

    Institute of Scientific and Technical Information of China (English)

    Matthias; L?hn; Oliver; Plettenburg; Aimo; Kannt; Markus; Kohlmann; Armin; Hofmeister; Dieter; Kadereit; Peter; Monecke; Alexander; Schiffer; Anke; Schulte; Hartmut; Ruetten; Yuri; Ivashchenko

    2015-01-01

    AIM: To compare the therapeutic efficacy of SAR407899 with the current standard treatment for hypertension [an angiotensin converting enzyme(ACE)-inhibitor and a calcium channel blocker] and compare the frequency and severity of the hypertension-related end-organ damage. METHODS: Long-term pharmacological characterization of SAR407899 has been performed in two animal models of hypertension, of which one is sensitive to ACE-inhibition and the other is insensitive [deoxycorticosterone acetate(DOCA)]. SAR407899 efficiently lowered high blood pressure and significantly reduced late-stage end organ damage as indicated by improved heart, kidney and endothelial function and reduced heart and kidney fibrosis in both models of chronic hypertension. RESULTS: Long term treatment with SAR407899 has been well tolerated and dose-dependently reduced elevated blood pressure in both models with no signs of tachyphylaxia. Blood pressure lowering effects and protective effects on hypertension related end organ damage of SAR407899 were superior to ramipril and amlodipine in the DOCA rat. Typical end-organ damage was significantly reduced in the SAR407899-treated animals. Chronic administration of SAR407899 significantly reduced albuminuria in both models. The beneficial effect of SAR407899 was associated with a reduction in leukocyte/macrophage tissue infiltration. The overall protective effect of SAR407899 was superior or comparable to that of ACE-inhibition or calciumchannel blockade. Chronic application of SAR407899 protects against hypertension and hypertension-induced end organ damage, regardless of the pathophysiological mechanism of hypertension. CONCLUSION: Rho-kinases-inhibition by the SAR407899 represents a new therapeutic option for the treatment of hypertension and its complications.

  14. PIKA Provides an Adjuvant Effect to Induce Strong Mucosal and Systemic Humoral Immunity Against SARS-CoV

    Institute of Scientific and Technical Information of China (English)

    Wei-wei Gai; Yan Zhang; Di-han Zhou; Yao-qing Chen; Jing-yi Yang; Hui-min Yan

    2011-01-01

    Severe Acute Respiratory Syndrome(SARS)is a deadly infectious disease caused by SARS Coronavirus(SARS-CoV).Inactivated SARS-CoV has been explored as a vaccine against SARS-CoV.However,safe and potent adjuvants,especially with more efficient and economical needle-free vaccination are always needed more urgently in a pandemic.The development of a safe and effective mucosal adjuvant and vaccine for prevention of emergent infectious diseases such as SARS will be an important advancement.PIKA,a stabilized derivative of Poly(I:C),was previously reported to be safe and potent as adjuvant in mouse models.In the present study,we demonstrated that the intraperitoneal and intranasal co-administration of inactivated SARS-CoV vaccine together with this improved Poly(I:C)derivative induced strong anti-SARS-CoV mucosal and systemic humoral immune responses with neutralizing activity against pseudotyped virus.Although intraperitoneal immunization of inactivated SARS-CoV vaccine alone could induce a certain level of neutralizing activity in serum as well as in mucosal sites,co-administration of inactivated SARS-CoV vaccine with PIKA as adjuvant could induce a much higher neutralizing activity.When intranasal immunization was used,PIKA was obligatorily for inducing neutralizing activity in serum as well as in mucosal sites and was correlated with both mucosal IgA and mucosal IgG response.Overall,PIKA could be a good mucosal adjuvant candidate for inactivated SARS-CoV vaccine for use in possible future pandemic.

  15. SARS: hospital infection control and admission strategies.

    Science.gov (United States)

    Ho, Pak-Leung; Tang, Xiao-Ping; Seto, Wing-Hong

    2003-11-01

    Nosocomial clustering with transmission to health care workers, patients and visitors is a prominent feature of severe acute respiratory syndrome (SARS). Hospital outbreaks of SARS typically occurred within the first week after admission of the very first SARS cases when the disease was not recognized and before isolation measures were implemented. In the majority of nosocomial infections, there was a history of close contact with a SARS patient, and transmission occurred via large droplets, direct contact with infectious material or by contact with fomites contaminated by infectious material. In a few instances, potential airborne transmission was reported in association with endotracheal intubation, nebulised medications and non-invasive positive pressure ventilation of SARS patients. In all SARS-affected countries, nosocomial transmission of the disease was effectively halted by enforcement of routine standard, contact and droplet precautions in all clinical areas and additional airborne precautions in the high-risk areas. In Hong Kong, where there are few private rooms for patient isolation, some hospitals have obtained good outcome by having designated SARS teams and separate wards for patient triage, confirmed SARS cases and step-down of patients in whom SARS had been ruled out. In conclusion, SARS represents one of the new challenges for those who are involved in hospital infection control. As SARS might re-emerge, all hospitals should take advantage of the current SARS-free interval to review their infection control programmes, alert mechanisms, response capability and to repair any identified inadequacies.

  16. SIMULATION STUDY ON AIRBORNE SAR ECHO SIGNAL

    Institute of Scientific and Technical Information of China (English)

    Bao Houbing; Liu Zhao

    2004-01-01

    Through analyzing the influence on echo signal by factors of kinematical parameters of airborne SAR platform and radar antenna direction, this letter, on the basis of classical SAR echo signal analogue algorithm, puts forward certain airborne SAR echo signal analogue algorithm of distance directional frequency domain pulse coherent accumulation, and goes through simulation. The simulation results have proved the effectiveness of this algorithm.

  17. Precision Rectification of Airborne SAR Image

    DEFF Research Database (Denmark)

    Dall, Jørgen; Liao, M.; Zhang, Zhe;

    1997-01-01

    A simple and direct procedure for the rectification of a certain class of airborne SAR data is presented. The relief displacements of SAR data are effectively removed by means of a digital elevation model and the image is transformed to the ground coordinate system. SAR data from the Danish EMISAR...

  18. Combination effect of oncolytic adenovirus therapy and herpes simplex virus thymidine kinase/ganciclovir in hepatic carcinoma animal models

    Institute of Scientific and Technical Information of China (English)

    Fei-qun ZHENG; Yin XU; Ren-jie YANG; Bin WU; Xiao-hua TAN; Yi-de QIN; Qun-wei ZHANG

    2009-01-01

    Aim: Oncolytic adenovirus, also called conditionally replicating adenovirus (CRAD), can selectively propagate in tumor cells and cause cell lysis. The released viral progeny can infect neighboring cancer cells, initiating a cascade that can lead to the ultimate destruction of the tumor. Suicide gene therapy using herpes simplex virus thymidine kinase (HSV-TK) and ganciclovir (GCV) offers a potential treatment strategy for cancer and is undergoing preclinical trials for a variety of tumors.We hypothesized that HSV-TK gene therapy combined with oncolytic adenoviral therapy would have an enhanced effect compared with the individual effects of the therapies and is a potential novel therapeutic strategy to treat liver cancer. Methods: To address our hypothesis, a novel CRAD was created, which consisted of a telomerase-dependent oncolytic adenovirus engineered to express E1A and HSV-TK genes (Ad-ETK). The combined effect of Ad-ETK and GCV was assessed both in vitro and in vivo in nude mice bearing HepG2 cell-derived tumors. Expression of the therapeutic genes by the transduced tumor cells was analyzed by RT-PCR and Western blotting.Results: We confirmed that Ad-ETK had antitumorigenic effects on human hepatocellular carcinoma (HCC) both in vitro and in vivo, and the TK/GCV system enhanced oncolytic adenoviral therapy. We confirmed that both E1A and HSV-TK genes were expressed in vivo.Conclusion: The Ad-ETK construct should provide a relatively safe and selective approach to killing cancer cells and should be investigated as an adjuvant therapy for hepatocellular carcinoma.

  19. Identification of IgH gene rearrangement and immunophenotype in an animal model of Epstein-Barr virus-associated lymphomas.

    Science.gov (United States)

    Zhang, Yang; Peng, Xueqin; Tang, Yunlian; Gan, Xiaoning; Wang, Chengkun; Xie, Lu; Xie, Xiaoli; Gan, Runliang; Wu, Yimou

    2016-10-01

    Epstein-Barr virus (EBV) is a human oncogenic herpesvirus associated with lymphoma and nasopharyngeal carcinoma. Because the susceptible hosts of EB virus are limited to human and cotton-top tamarins (Saguinus oedipus), there have been no appropriate animal models until the lymphoma model induced by EBV in human peripheral blood lymphocyte (hu-PBL)/SCID chimeric mice was reported. However, it is still controversial whether the EBV-associated lymphoma induced in hu-PBL/SCID mice is a monoclonal tumor. In this study, we transplanted normal human peripheral blood lymphocytes (hu-PBL) from six donors infected with EBV into SCID mice to construct hu-PBL/SCID chimeric mice. The induced tumors were found in the mediastinum or abdominal cavity of SCID mice. Microscopic observation exhibited tumor cells that were large and had a plasmablastic, centroblastic or immunoblastic-like appearance. Immunophenotyping assays showed the induced tumors were LCA-positive, CD20/CD79a-positive (markers of B cells), and CD3/CD45RO-negative (markers of T cells). A human-specific Alu sequence could be amplified by Alu-PCR. This confirmed that induced tumors were B-cell lymphomas originating from the transplanted human lymphocytes rather than mouse cells. EBER in situ hybridization detected positive signals in the nuclei of the tumor cells. Expression of EBV-encoded LMP1, EBNA-1, and EBNA-2 in the tumors was significantly positive. PCR-based capillary electrophoresis analysis of IgH gene rearrangement revealed a monoclonal peak and single amplification product in all six cases of induced tumors. This indicated that EBV can induce monoclonal proliferation of human B lymphocytes and promotes the development of lymphoma. J. Med. Virol. 88:1804-1813, 2016. © 2016 Wiley Periodicals, Inc. PMID:26991077

  20. 9 CFR 117.2 - Animal facilities.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Animal facilities. 117.2 Section 117.2 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS ANIMALS AT LICENSED ESTABLISHMENTS §...

  1. 9 CFR 117.4 - Test animals.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Test animals. 117.4 Section 117.4 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS ANIMALS AT LICENSED ESTABLISHMENTS §...

  2. Protein Subcellular Localization Prediction and Genomic Polymorphism Analysis of the SARS Coronavirus

    Institute of Scientific and Technical Information of China (English)

    季星来; 柳树群; 李岭; 孙之荣

    2004-01-01

    The cause of severe acute respiratory syndrome (SARS) has been identified as a new coronavirus (CoV).Several sequences of the complete genome of SARS-CoV have been determined.The subcellular localization (SubLocation) of annotated open-reading frames of the SARS-CoV genome was predicted using a support vector machine.Several gene products were predicted to locate in the Golgi body and cell nucleus.The SubLocation information was combined with predicted transmembrane information to develop a model of the viral life cycle.The results show that this information can be used to predict the functions of genes and even the virus pathogenesis.In addition,the entire SARS viral genome sequences currently available in GenBank were compared to identify the sequence variations among different isolates.Some variations in the Hong Kong strains may be related to the special clinical manifestations and provide clues for understanding the relationship between gene functions and evolution.These variations reflect the evolution of the SARS virus in human populations and may help development of a vaccine.

  3. Chimeric Bivalent Virus-Like Particle Vaccine for H5N1 HPAI and ND Confers Protection against a Lethal Challenge in Chickens and Allows a Strategy of Differentiating Infected from Vaccinated Animals (DIVA)

    Science.gov (United States)

    Noh, Jin-Yong; Park, Jae-Keun; Lee, Dong-Hun; Yuk, Seong-Su; Kwon, Jung-Hoon; Lee, Sang-Won; Lee, Joong-Bok; Park, Seung-Yong; Choi, In-Soo; Song, Chang-Seon

    2016-01-01

    Highly pathogenic avian influenza (HPAI) and Newcastle disease (ND) are considered as the most devastating poultry infections, owing to their worldwide distribution and economical threat. Vaccines have been widely used to control these diseases in the poultry industry in endemic countries. However, vaccination policy without differentiating infected animals from vaccinated animals (DIVA) makes the virus surveillance difficult. In this study, we developed a bivalent virus-like particle (VLP) vaccine that is composed of the hemagglutinin (HA) and matrix 1 (M1) proteins of the H5N1 HPAI virus (HPAIV) and a chimeric protein containing the ectodomain of the ND virus (NDV) fusion (F) protein fused with the cytoplasmic and transmembrane domains of the HPAIV HA protein. A single immunization of chickens with the chimeric VLP vaccine induced high levels of hemagglutination inhibition (HI) antibody titers against H5N1 HPAI virus and anti-NDV antibody detected in ELISA and protected chickens against subsequent lethal HPAIV and NDV infections. Furthermore, we could easily perform DIVA test using the commercial NP-cELISA tests against HPAIV and HI assay against NDV. These results strongly suggest that utilization of chimeric VLP vaccine in poultry species would be a promising strategy for the better control of HPAI and ND simultaneously. PMID:27626934

  4. Chimeric Bivalent Virus-Like Particle Vaccine for H5N1 HPAI and ND Confers Protection against a Lethal Challenge in Chickens and Allows a Strategy of Differentiating Infected from Vaccinated Animals (DIVA).

    Science.gov (United States)

    Noh, Jin-Yong; Park, Jae-Keun; Lee, Dong-Hun; Yuk, Seong-Su; Kwon, Jung-Hoon; Lee, Sang-Won; Lee, Joong-Bok; Park, Seung-Yong; Choi, In-Soo; Song, Chang-Seon

    2016-01-01

    Highly pathogenic avian influenza (HPAI) and Newcastle disease (ND) are considered as the most devastating poultry infections, owing to their worldwide distribution and economical threat. Vaccines have been widely used to control these diseases in the poultry industry in endemic countries. However, vaccination policy without differentiating infected animals from vaccinated animals (DIVA) makes the virus surveillance difficult. In this study, we developed a bivalent virus-like particle (VLP) vaccine that is composed of the hemagglutinin (HA) and matrix 1 (M1) proteins of the H5N1 HPAI virus (HPAIV) and a chimeric protein containing the ectodomain of the ND virus (NDV) fusion (F) protein fused with the cytoplasmic and transmembrane domains of the HPAIV HA protein. A single immunization of chickens with the chimeric VLP vaccine induced high levels of hemagglutination inhibition (HI) antibody titers against H5N1 HPAI virus and anti-NDV antibody detected in ELISA and protected chickens against subsequent lethal HPAIV and NDV infections. Furthermore, we could easily perform DIVA test using the commercial NP-cELISA tests against HPAIV and HI assay against NDV. These results strongly suggest that utilization of chimeric VLP vaccine in poultry species would be a promising strategy for the better control of HPAI and ND simultaneously. PMID:27626934

  5. Polarimetric scattering and SAR information retrieval

    CERN Document Server

    Jin, Ya-Qiu

    2013-01-01

    Taking an innovative look at Synthetic Aperture Radar (SAR), this practical reference fully covers new developments in SAR and its various methodologies and enables readers to interpret SAR imagery An essential reference on polarimetric Synthetic Aperture Radar (SAR), this book uses scattering theory and radiative transfer theory as a basis for its treatment of topics. It is organized to include theoretical scattering models and SAR data analysis techniques, and presents cutting-edge research on theoretical modelling of terrain surface. The book includes quantitative app

  6. A Strategy for Searching Antigenic Regions in the SARS-CoV Spike Protein

    Institute of Scientific and Technical Information of China (English)

    Yan Ren; Cuiqi Zhou; Jingqiang Wang; Jianning Yin; Ningzhi Xu; Siqi Liu; Zhengfeng Zhou; Jinxiu Liu; Liang Lin; Shuting Li; Hao Wang; Ji Xia; Zhe Zhao; Jie Wen

    2003-01-01

    In the face of the worldwide threat of severe acute respiratory syndrome (SARS)to human life, some of the most urgent challenges are to develop fast and accurate analytical methods for early diagnosis of this disease as well as to create a safe anti-viral vaccine for prevention. To these ends, we investigated the antigenicity of the spike protein (S protein), a major structural protein in the SARS-coronavirus (SARS-CoV). Based upon the theoretical analysis for hydrophobicity of the S protein, 18 peptides were synthesized. Using Enzyme-Linked Immunosorbent Assay (ELISA), these peptides were screened in the sera from SARS patients. According to these results, two fragments of the S gene were amplified by PCR and cloned into pET-32a. Both S fragments were expressed in the BL-21 strain and further purified with an affinity chromatography. These recombinant S fragments were confirmed to have positive cross-reactions with SARS sera, either by Western blot or by ELISA. Our results demonstrated that the potential epitope regions were located at Codons 469-882 in the S protein, and one epitope site was located at Codons 599-620. Identification of antigenic regions in the SARS-CoV S protein may be important for the functional studies of this virus or the development of clinical diagnosis.

  7. Development of a method for bacteria and virus recovery from heating, ventilation, and air conditioning (HVAC) filters.

    Science.gov (United States)

    Farnsworth, James E; Goyal, Sagar M; Kim, Seung Won; Kuehn, Thomas H; Raynor, Peter C; Ramakrishnan, M A; Anantharaman, Senthilvelan; Tang, Weihua

    2006-10-01

    The aim of the work presented here is to study the effectiveness of building air handling units (AHUs) in serving as high volume sampling devices for airborne bacteria and viruses. An HVAC test facility constructed according to ASHRAE Standard 52.2-1999 was used for the controlled loading of HVAC filter media with aerosolized bacteria and virus. Nonpathogenic Bacillus subtilis var. niger was chosen as a surrogate for Bacillus anthracis. Three animal viruses; transmissible gastroenteritis virus (TGEV), avian pneumovirus (APV), and fowlpox virus were chosen as surrogates for three human viruses; SARS coronavirus, respiratory syncytial virus, and smallpox virus; respectively. These bacteria and viruses were nebulized in separate tests and injected into the test duct of the test facility upstream of a MERV 14 filter. SKC Biosamplers upstream and downstream of the test filter served as reference samplers. The collection efficiency of the filter media was calculated to be 96.5 +/- 1.5% for B. subtilis, however no collection efficiency was measured for the viruses as no live virus was ever recovered from the downstream samplers. Filter samples were cut from the test filter and eluted by hand-shaking. An extraction efficiency of 105 +/- 19% was calculated for B. subtilis. The viruses were extracted at much lower efficiencies (0.7-20%). Our results indicate that the airborne concentration of spore-forming bacteria in building AHUs may be determined by analyzing the material collected on HVAC filter media, however culture-based analytical techniques are impractical for virus recovery. Molecular-based identification techniques such as PCR could be used.

  8. Canopy reconstruction from interferometric SAR

    NARCIS (Netherlands)

    Varekamp, C.

    2001-01-01

    Interferometric Synthetic Aperture Radar (InSAR) is investigated as a method for 3D tree mapping. When operational, the method may be important for monitoring forests with a persistent cloud cover such as tropical rain forests. The problem of crown displacement due to lay-over in a vegetation with a

  9. Signal processing for FMCW SAR

    NARCIS (Netherlands)

    Meta, A.; Hoogeboom, P.; Ligthart, L.P.

    2007-01-01

    The combination of frequency-modulated continuous-wave (FMCW) technology and synthetic aperture radar (SAR) techniques leads to lightweight cost-effective imaging sensors of high resolution. One limiting factor to the use of FMCW sensors is the well-known presence of nonlinearities in the transmitte

  10. Stalking SARS: CDC at Work

    Centers for Disease Control (CDC) Podcasts

    2014-05-22

    In this podcast for kids, the Kidtastics talk about the SARS outbreak and how CDC worked to solve the mystery.  Created: 5/22/2014 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 5/22/2014.

  11. Light weight digital array SAR

    NARCIS (Netherlands)

    Otten, M.; Maas, N.; Bolt, R.; Anitori, L.

    2010-01-01

    A light weight SAR has been designed, suitable for short range tactical UAVs, consisting of a fully digital receive array, and a very compact active transmit antenna. The weight of the complete RF front is expected to be below 3 kg, with a power consumption below 30 W. This X-band system can provide

  12. 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 Virus. 113.215 Section 113.215 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS...

  13. Elicitation of strong immune responses by a DNA vaccine expressing a secreted form of hepatitis C virus envelope protein E2 in murine and porcine animal models

    Institute of Scientific and Technical Information of China (English)

    Yi-Ping Li; Hye Na Kang; Lorne A Babiuk; Qiang Liu

    2006-01-01

    AIM: To characterize the immunogenicity of a hepatitis C virus (HCV) E2 DNA vaccine alone or with a protein vaccine boost in murine and porcine animal models.METHODS: A DNA vaccine expressing a secreted form of HCV E2 protein was constructed and used to vaccinate mice and piglets with or without boosting with a recombinant E2 protein vaccine formulated with CpG ODN and 10% Emulsigen. The immunogenicity of HCV E2 vaccines was analyzed by ELISA for antibody responses, MTT assay for lymphocyte proliferation,ELISPOT for the number of interferon-γ secreting cells,and cytotoxic T lymphocyte assays.RESULTS: Intradermal injection of E2 DNA vaccine induced strong Th1-like immune responses in mice. In piglets, E2 DNA vaccine elicited moderate and more balanced immune responses. A DNA vaccine prime and protein boost vaccination strategy induced significantly higher E2-specific antibody levels and shifted the immune response towards Th2-like ones in piglets.CONCLUSION: A DNA vaccine expressing a secreted form of HCV E2 protein elicited E2-specific immune responses in mice and piglets. Recombinant E2 protein vaccination following DNA immunization significantly increased the antibody response in piglets. These HCV E2 vaccines may represent promising hepatitis C vaccine candidates for further investigations.

  14. Preparation, characterization and preliminary in vivo studies of inactivated SARS-CoV vaccine

    Institute of Scientific and Technical Information of China (English)

    TANG Lin; CHANG Guohui; LI Shuangli; ZHANG Xumin; CHEN Xishu; YU Jun; CHEN Ze; WANG Jian; QIN Ede; ZHU Qingyu; YU Man; DING Zhifen; SHI Huiying; CHENG Xiaojie; WANG Caiping

    2003-01-01

    A large quantity of SARS-CoV virus was proliferated in Vero cells, inactivated with β-propiolactone, then purified by Sepharose 4FF column chromatography to prepare inactivated vaccine. The vaccine was identified by Western blot, mass spectrographic analysis, ELISA and electron microscopy. The vaccine with or without aluminum hydroxide adjuvant was inoculated into female BALB/c mice at different dosages. The result showed that the antibodies to SARS-CoV were induced in the mice. The antibody levels induced by the vaccine with aluminum hydroxide were higher than those without aluminum hydroxide.

  15. Human LINE1 endonuclease domain as a putative target of SARS-associated autoantibodies involved in the pathogenesis of severe acute respiratory syndrome

    Institute of Scientific and Technical Information of China (English)

    HE Wei-ping; SHU Cui-li; LI Bo-an; ZHAO Jun; CHENG Yun

    2008-01-01

    Background Severe acute respiratory syndrome(SARS)is a disease with a mortality of 9.56%.Although SARS is etiologically linked to a new coronavirus(SARS-CoV)and functional cell receptor has been identified,the pathogenesis of the virus infection is largely unclear.Methods The clinical specimens were processed and analyzed using an indirect enzyme-linked immunosorbent assay (ELISA) in-house.Further investigations of target antigen included reviews of phage display technique,rapid amplification of cDNA ends(RACE)technique,protein expression and purification,Western blotting validation,serological and immunohistochemical staining in postmortem tissue.Results A type of medium or low titer anti-lung tissue antibodies were found in the sera of SARS patients at the early stage of the disease.Human long interspersed nuclear element 1(LINE1)gene endonuclease(EN)domain protein was one of the target autoantigens and it was aberrantly expressed in the lung tissue of SARS patients.Anti-EN antibody was positive in the sera of 40.9% of SARS patients.Conclusions Human LINE1 endonuclease domain was identified as a putative target of SARS-associated autoantibodies,which were presented in the serum of SARS patients and may be involved in the pathogenesis of SARS.

  16. 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.

  17. 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 dose from the lot of Master Seed Virus shall be established as follows: (1) Twenty-five...

  18. Reflectors for SAR performance testing.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2008-01-01

    Synthetic Aperture Radar (SAR) performance testing and estimation is facilitated by observing the system response to known target scene elements. Trihedral corner reflectors and other canonical targets play an important role because their Radar Cross Section (RCS) can be calculated analytically. However, reflector orientation and the proximity of the ground and mounting structures can significantly impact the accuracy and precision with which measurements can be made. These issues are examined in this report.

  19. SAR Image Complex Pixel Representations

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-01

    Complex pixel values for Synthetic Aperture Radar (SAR) images of uniform distributed clutter can be represented as either real/imaginary (also known as I/Q) values, or as Magnitude/Phase values. Generally, these component values are integers with limited number of bits. For clutter energy well below full-scale, Magnitude/Phase offers lower quantization noise than I/Q representation. Further improvement can be had with companding of the Magnitude value.

  20. Signal Processing for Digital Beamforming FMCW SAR

    Directory of Open Access Journals (Sweden)

    Qin Xin

    2014-01-01

    Full Text Available According to the limitations of single channel Frequency Modulation Continuous Wave (FMCW Synthetic Aperture Radar (SAR, Digital Beamforming (DBF technology is introduced to improve system performance. Combined with multiple receive apertures, DBF FMCW SAR can obtain high resolution in low pulse repetition frequency, which can increase the processing gain and decrease the sampling frequency. The received signal model of DBF FMCW SAR is derived. The continuous antenna motion which is the main characteristic of FMCW SAR received signal is taken into account in the whole signal processing. The detailed imaging diagram of DBF FMCW SAR is given. A reference system is also demonstrated in the paper by comparing with a single channel FMCW SAR. The validity of the presented diagram is demonstrated with a point target simulation results.

  1. INSTANTANEOUS DOPPLER FREQUENCY FOR SQUINT SAR IMAGING

    Institute of Scientific and Technical Information of China (English)

    Liu Guangyan; Huang Shunji

    2003-01-01

    Instantaneous Doppler frequency for squint SAR imaging has been found with ChirpScaling Algorithm (CSA). Because the azimuth sample is not perpendicular to the range sample,the range signal must impact on the azimuth signal in the squint SAR data processing, andthe different slant range targets have different Doppler frequencies. From the mathematicalmodel of SAR echo signal, this paper carefully analyzes the instantaneous azimuth frequency, theinstantaneous Doppler frequency component of the azimuth frequency and the impact of rangechirp on azimuth frequency, which explains that Doppler frequency should be properly selected forcorrect SAR imaging in the squint SAR. The results of point target simulation experiments showthat the way is reasonable for the squint SAR and can effectively complete range compressionand azimuth focusing, and improve images' quality.

  2. Convolutional Neural Networks for SAR Image Segmentation

    DEFF Research Database (Denmark)

    Malmgren-Hansen, David; Nobel-Jørgensen, Morten

    2015-01-01

    Segmentation of Synthetic Aperture Radar (SAR) images has several uses, but it is a difficult task due to a number of properties related to SAR images. In this article we show how Convolutional Neural Networks (CNNs) can easily be trained for SAR image segmentation with good results. Besides...... this contribution we also suggest a new way to do pixel wise annotation of SAR images that replaces a human expert manual segmentation process, which is both slow and troublesome. Our method for annotation relies on 3D CAD models of objects and scene, and converts these to labels for all pixels in a SAR image. Our...... algorithms are evaluated on the Moving and Stationary Target Acquisition and Recognition (MSTAR) dataset which was released by the Defence Advanced Research Projects Agency during the 1990s. The method is not restricted to the type of targets imaged in MSTAR but can easily be extended to any SAR data where...

  3. Spaceborne SAR Imaging Algorithm for Coherence Optimized.

    Directory of Open Access Journals (Sweden)

    Zhiwei Qiu

    Full Text Available This paper proposes SAR imaging algorithm with largest coherence based on the existing SAR imaging algorithm. The basic idea of SAR imaging algorithm in imaging processing is that output signal can have maximum signal-to-noise ratio (SNR by using the optimal imaging parameters. Traditional imaging algorithm can acquire the best focusing effect, but would bring the decoherence phenomenon in subsequent interference process. Algorithm proposed in this paper is that SAR echo adopts consistent imaging parameters in focusing processing. Although the SNR of the output signal is reduced slightly, their coherence is ensured greatly, and finally the interferogram with high quality is obtained. In this paper, two scenes of Envisat ASAR data in Zhangbei are employed to conduct experiment for this algorithm. Compared with the interferogram from the traditional algorithm, the results show that this algorithm is more suitable for SAR interferometry (InSAR research and application.

  4. Spaceborne SAR Imaging Algorithm for Coherence Optimized.

    Science.gov (United States)

    Qiu, Zhiwei; Yue, Jianping; Wang, Xueqin; Yue, Shun

    2016-01-01

    This paper proposes SAR imaging algorithm with largest coherence based on the existing SAR imaging algorithm. The basic idea of SAR imaging algorithm in imaging processing is that output signal can have maximum signal-to-noise ratio (SNR) by using the optimal imaging parameters. Traditional imaging algorithm can acquire the best focusing effect, but would bring the decoherence phenomenon in subsequent interference process. Algorithm proposed in this paper is that SAR echo adopts consistent imaging parameters in focusing processing. Although the SNR of the output signal is reduced slightly, their coherence is ensured greatly, and finally the interferogram with high quality is obtained. In this paper, two scenes of Envisat ASAR data in Zhangbei are employed to conduct experiment for this algorithm. Compared with the interferogram from the traditional algorithm, the results show that this algorithm is more suitable for SAR interferometry (InSAR) research and application. PMID:26871446

  5. Spaceborne SAR Imaging Algorithm for Coherence Optimized

    Science.gov (United States)

    Qiu, Zhiwei; Yue, Jianping; Wang, Xueqin; Yue, Shun

    2016-01-01

    This paper proposes SAR imaging algorithm with largest coherence based on the existing SAR imaging algorithm. The basic idea of SAR imaging algorithm in imaging processing is that output signal can have maximum signal-to-noise ratio (SNR) by using the optimal imaging parameters. Traditional imaging algorithm can acquire the best focusing effect, but would bring the decoherence phenomenon in subsequent interference process. Algorithm proposed in this paper is that SAR echo adopts consistent imaging parameters in focusing processing. Although the SNR of the output signal is reduced slightly, their coherence is ensured greatly, and finally the interferogram with high quality is obtained. In this paper, two scenes of Envisat ASAR data in Zhangbei are employed to conduct experiment for this algorithm. Compared with the interferogram from the traditional algorithm, the results show that this algorithm is more suitable for SAR interferometry (InSAR) research and application. PMID:26871446

  6. Elementary study on the antigenicity of SARS-CoV Mc region

    Institute of Scientific and Technical Information of China (English)

    ZU QIONG HU; WEI ZHAO; WEN BING ZHANG; HUI JUN YAN; LI FANG JIANG; ZHI WEI LIU; ZHI HUA LIU; BEI GUO LONG

    2006-01-01

    To test the antigenic activity of M protein (Mc protein) in the inner membrane of SARS-CoV,SARS-CoV Mc protein's bases locating inside the membrane were cloned, the His-fusion protein was expressed in E. coli and analyzed for its antigenic activity. Among those 7 clinically diagnosed patients' sera, there were 5 positive and 2 negative in reaction with His-fusion protein. All of the 20 healthy persons'sera and rabbit anti-OC43 and 229E were of negative reaction with His-fusion protein. The animals immunized with His-fusion protein have produced multi-clonal antibody. The His-fusion protein could specially react with clinically diagnosed SARS patients' sera and the animals immunized with His-fusion protein could produce specifically multi-clonal antibody, but it could not react with the sera of healthy persons and the rabbit anti-OC43 and 229E.

  7. InSAR Forensics: Tracing InSAR Scatterers in High Resolution Optical Image

    Science.gov (United States)

    Wang, Yuanyuan; Zhu, XiaoXiang

    2015-05-01

    This paper presents a step towards a better interpretation of the scattering mechanism of different objects and their deformation histories in SAR interferometry (InSAR). The proposed technique traces individual SAR scatterer in high resolution optical images where their geometries, materials, and other properties can be better analyzed and classified. And hence scatterers of a same object can be analyzed in group, which brings us to a new level of InSAR deformation monitoring.

  8. Signal Processing for Digital Beamforming FMCW SAR

    OpenAIRE

    Qin Xin; Zhihong Jiang; Pu Cheng; Mi He

    2014-01-01

    According to the limitations of single channel Frequency Modulation Continuous Wave (FMCW) Synthetic Aperture Radar (SAR), Digital Beamforming (DBF) technology is introduced to improve system performance. Combined with multiple receive apertures, DBF FMCW SAR can obtain high resolution in low pulse repetition frequency, which can increase the processing gain and decrease the sampling frequency. The received signal model of DBF FMCW SAR is derived. The continuous antenna motion which is the ma...

  9. Satellite SAR geocoding with refined RPC model

    Science.gov (United States)

    Zhang, Lu; Balz, Timo; Liao, Mingsheng

    2012-04-01

    Recent studies have proved that the Rational Polynomial Camera (RPC) model is able to act as a reliable replacement of the rigorous Range-Doppler (RD) model for the geometric processing of satellite SAR datasets. But its capability in absolute geolocation of SAR images has not been evaluated quantitatively. Therefore, in this article the problems of error analysis and refinement of SAR RPC model are primarily investigated to improve the absolute accuracy of SAR geolocation. Range propagation delay and azimuth timing error are identified as two major error sources for SAR geolocation. An approach based on SAR image simulation and real-to-simulated image matching is developed to estimate and correct these two errors. Afterwards a refined RPC model can be built from the error-corrected RD model and then used in satellite SAR geocoding. Three experiments with different settings are designed and conducted to comprehensively evaluate the accuracies of SAR geolocation with both ordinary and refined RPC models. All the experimental results demonstrate that with RPC model refinement the absolute location accuracies of geocoded SAR images can be improved significantly, particularly in Easting direction. In another experiment the computation efficiencies of SAR geocoding with both RD and RPC models are compared quantitatively. The results show that by using the RPC model such efficiency can be remarkably improved by at least 16 times. In addition the problem of DEM data selection for SAR image simulation in RPC model refinement is studied by a comparative experiment. The results reveal that the best choice should be using the proper DEM datasets of spatial resolution comparable to that of the SAR images.

  10. MiniSAR: a miniature, lightweight, low cost, scalable SAR system

    NARCIS (Netherlands)

    Steeghs, T.P.H.; Halsema, D. van; Hoogeboom, P.

    2001-01-01

    TNO-FEL is developing a miniature, lightweight, low cost, and scalable SAR/MTI system called 'MiniSAR'. The MiniSAR system will be unique in its size and architecture. Initially the demonstrator system will be integrated in a two-seater motorglider platform. Wherever possible, commercial-off-the-she

  11. DETEKCIJA SPREMEMB V RADARSKIH SLIKAH SAR

    OpenAIRE

    Izak, Rok

    2016-01-01

    V magistrskem delu je opisan princip detekcije sprememb površja Zemlje s pomočjo radarskih slik SAR, ki so bile zajete s satelitom TanDEM-X. Opisani so tudi principi delovanja radarja z umetno odprtino, načini zajema podatkov ter osnove interferometrije V prvem sklopu magistrskega dela, je bil cilj predlagati metodo za zaznavo gozdne površine v slikah SAR. V drugem delu so bile s pomočjo SAR interferometrije zaznane spremembe na kroni gozdov v okolici Postojne. Slike SAR, so bile zajete v raz...

  12. A Research on Airborne Squint Hybrid SAR

    Institute of Scientific and Technical Information of China (English)

    BIANYong; ZHOUYinqing; LIChunsheng

    2004-01-01

    In this paper, we establish the squint mode hybrid SAR (Synthetic aperture radar) geometry. Based on the squint mode SAR geometry, the hybrid SAR signal model in squint case is derived. Based on this signal model, the hybrid SAR imaging process parameter is discussed. Aimed at the squint case, we analyze not only the relationship between the resolution and SAR system parameters, but also the relation between the time extension of the maximum azimuth signal and SAR system parameters. This research establishes the theoretical foundation for the design of squint hybrid SAR and serves as a good guide for the future work of improving the resolution of squint hybrid SAR. Based on the two-step algorithm, by considering the squint angle and cubic phase term, we are going to use the deramp SC-Chirp Scaling algorithm for squint hybrid SAR imaging. This algorithm uses the deramp method for the first step processing, and the SC-Chirp Scaling algorithm for the second step processing. The process procedure of this algorithm includes the squint angle, has the explicit physical meaning, therefore is convenient for analysis. The computer simulation result proves the validity of the analysis.

  13. Bistatic SAR: Signal Processing and Image Formation.

    Energy Technology Data Exchange (ETDEWEB)

    Wahl, Daniel E.; Yocky, David A.

    2014-10-01

    This report describes the significant processing steps that were used to take the raw recorded digitized signals from the bistatic synthetic aperture RADAR (SAR) hardware built for the NCNS Bistatic SAR project to a final bistatic SAR image. In general, the process steps herein are applicable to bistatic SAR signals that include the direct-path signal and the reflected signal. The steps include preprocessing steps, data extraction to for a phase history, and finally, image format. Various plots and values will be shown at most steps to illustrate the processing for a bistatic COSMO SkyMed collection gathered on June 10, 2013 on Kirtland Air Force Base, New Mexico.

  14. SARS transmission pattern in Singapore reassessed by viral sequence variation analysis.

    Directory of Open Access Journals (Sweden)

    Jianjun Liu

    2005-02-01

    Full Text Available BACKGROUND: Epidemiological investigations of infectious disease are mainly dependent on indirect contact information and only occasionally assisted by characterization of pathogen sequence variation from clinical isolates. Direct sequence analysis of the pathogen, particularly at a population level, is generally thought to be too cumbersome, technically difficult, and expensive. We present here a novel application of mass spectrometry (MS-based technology in characterizing viral sequence variations that overcomes these problems, and we apply it retrospectively to the severe acute respiratory syndrome (SARS outbreak in Singapore. METHODS AND FINDINGS: The success rate of the MS-based analysis for detecting SARS coronavirus (SARS-CoV sequence variations was determined to be 95% with 75 copies of viral RNA per reaction, which is sufficient to directly analyze both clinical and cultured samples. Analysis of 13 SARS-CoV isolates from the different stages of the Singapore outbreak identified nine sequence variations that could define the molecular relationship between them and pointed to a new, previously unidentified, primary route of introduction of SARS-CoV into the Singapore population. Our direct determination of viral sequence variation from a clinical sample also clarified an unresolved epidemiological link regarding the acquisition of SARS in a German patient. We were also able to detect heterogeneous viral sequences in primary lung tissues, suggesting a possible coevolution of quasispecies of virus within a single host. CONCLUSION: This study has further demonstrated the importance of improving clinical and epidemiological studies of pathogen transmission through the use of genetic analysis and has revealed the MS-based analysis to be a sensitive and accurate method for characterizing SARS-CoV genetic variations in clinical samples. We suggest that this approach should be used routinely during outbreaks of a wide variety of agents, in order

  15. A Comparison of the Pathogenesis of Marburg Virus Disease in Humans and Nonhuman Primates and Evaluation of the Suitability of These Animal Models for Predicting Clinical Efficacy under the ‘Animal Rule’

    OpenAIRE

    Glaze, Elizabeth R.; Roy, Michael J; Dalrymple, Lonnie W; Lanning, Lynda L

    2015-01-01

    Marburg virus outbreaks are sporadic, infrequent, brief, and relatively small in terms of numbers of subjects affected. In addition, outbreaks most likely will occur in remote regions where clinical trials are not feasible; therefore, definitive, well-controlled human efficacy studies to test the effectiveness of a drug or biologic product are not feasible. Healthy human volunteers cannot ethically be deliberately exposed to a lethal agent such as Marburg virus in order to test the efficacy o...

  16. 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.

  17. Design and application of 60mer oligonucleotide microarray in SARS coronavirus detection

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The 60mer oligonucleotide microarray was designed and applied to detecting of SARS (severe acute respiratory syndrome) coronavirus. Thirty 60mer specific oligos were designed to cover the whole genome of the first submitted coronavirus strain, according to the sequence of TOR2 (GENEBANK Accession: AY274119). These primers were synthesized and printed into a microarray with 12×12 spots. RNAs were extracted from the throat swab and gargling fluid of SARS patients and reverse-transcripted into the double strand cDNAs. The cDNAs were prepared as restricted cDNA fragments by the restriction display (RD) technique and labeled by PCR with the Cy5-universal primer. The labeled samples were then applied to the oligo microarray for hybridization. The diagnostic capability of the microarray was evaluated after the washing and scanning steps. The scanning result showed that samples of SARS patients were hybridized with multiple SARS probes on the microarray, and there is no signal on the negative and blank controls. These results indicate that the genome of SARS coronavirus can be detected in parallel by the 60mer oligonucleotide microarray, which can improve the positive ratio of the diagnosis. The oligo microarray can also be used for monitoring the behavior of the virus genes in different stages of the disease status.

  18. 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...

  19. 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...

  20. Differential sensitivity of bat cells to infection by enveloped RNA viruses: coronaviruses, paramyxoviruses, filoviruses, and influenza viruses.

    Directory of Open Access Journals (Sweden)

    Markus Hoffmann

    Full Text Available Bats (Chiroptera host major human pathogenic viruses including corona-, paramyxo, rhabdo- and filoviruses. We analyzed six different cell lines from either Yinpterochiroptera (including African flying foxes and a rhinolophid bat or Yangochiroptera (genera Carollia and Tadarida for susceptibility to infection by different enveloped RNA viruses. None of the cells were sensitive to infection by transmissible gastroenteritis virus (TGEV, a porcine coronavirus, or to infection mediated by the Spike (S protein of SARS-coronavirus (SARS-CoV incorporated into pseudotypes based on vesicular stomatitis virus (VSV. The resistance to infection was overcome if cells were transfected to express the respective cellular receptor, porcine aminopeptidase N for TGEV or angiotensin-converting enzyme 2 for SARS-CoV. VSV pseudotypes containing the S proteins of two bat SARS-related CoV (Bg08 and Rp3 were unable to infect any of the six tested bat cell lines. By contrast, viral pseudotypes containing the surface protein GP of Marburg virus from the family Filoviridae infected all six cell lines though at different efficiency. Notably, all cells were sensitive to infection by two paramyxoviruses (Sendai virus and bovine respiratory syncytial virus and three influenza viruses from different subtypes. These results indicate that bat cells are more resistant to infection by coronaviruses than to infection by paramyxoviruses, filoviruses and influenza viruses. Furthermore, these results show a receptor-dependent restriction of the infection of bat cells by CoV. The implications for the isolation of coronaviruses from bats are discussed.

  1. Avian influenza virus, Streptococcus suis serotype 2, severe acute respiratory syndrome-coronavirus and beyond: molecular epidemiology, ecology and the situation in China.

    Science.gov (United States)

    Ma, Ying; Feng, Youjun; Liu, Di; Gao, George F

    2009-09-27

    The outbreak and spread of severe acute respiratory syndrome-associated coronavirus and the subsequent identification of its animal origin study have heightened the world's awareness of animal-borne or zoonotic pathogens. In addition to SARS, the highly pathogenic avian influenza virus (AIV), H5N1, and the lower pathogenicity H9N2 AIV have expanded their host ranges to infect human beings and other mammalian species as well as birds. Even the 'well-known' reservoir animals for influenza virus, migratory birds, became victims of the highly pathogenic H5N1 virus. Not only the viruses, but bacteria can also expand their host range: a new disease, streptococcal toxic shock syndrome, caused by human Streptococcus suis serotype 2 infection, has been observed in China with 52 human fatalities in two separate outbreaks (1998 and 2005, respectively). Additionally, enterohaemorrhagic Escherichia coli O157:H7 infection has increased worldwide with severe disease. Several outbreaks and sporadic isolations of this pathogen in China have made it an important target for disease control. A new highly pathogenic variant of porcine reproductive and respiratory syndrome virus (PRRSV) has been isolated in both China and Vietnam recently; although PRRSV is not a zoonotic human pathogen, its severe outbreaks have implications for food safety. All of these pathogens occur in Southeast Asia, including China, with severe consequences; therefore, we discuss the issues in this article by addressing the situation of the zoonotic threat in China. PMID:19687041

  2. Sentinel-3 SAR Altimetry Toolbox

    Science.gov (United States)

    Benveniste, Jerome; Lucas, Bruno; DInardo, Salvatore

    2015-04-01

    The prime objective of the SEOM (Scientific Exploitation of Operational Missions) element is to federate, support and expand the large international research community that the ERS, ENVISAT and the Envelope programmes have build up over the last 20 years for the future European operational Earth Observation missions, the Sentinels. Sentinel-3 builds directly on a proven heritage of ERS-2 and Envisat, and CryoSat-2, with a dual-frequency (Ku and C band) advanced Synthetic Aperture Radar Altimeter (SRAL) that provides measurements at a resolution of ~300m in SAR mode along track. Sentinel-3 will provide exact measurements of sea-surface height along with accurate topography measurements over sea ice, ice sheets, rivers and lakes. The first of the two Sentinels is expected to be launched in early 2015. The current universal altimetry toolbox is BRAT (Basic Radar Altimetry Toolbox) which can read all previous and current altimetry mission's data, but it does not have the capabilities to read the upcoming Sentinel-3 L1 and L2 products. ESA will endeavour to develop and supply this capability to support the users of the future Sentinel-3 SAR Altimetry Mission. BRAT is a collection of tools and tutorial documents designed to facilitate the processing of radar altimetry data. This project started in 2005 from the joint efforts of ESA (European Space Agency) and CNES (Centre National d'Etudes Spatiales), and it is freely available at http://earth.esa.int/brat. The tools enable users to interact with the most common altimetry data formats, the BratGUI is the front-end for the powerful command line tools that are part of the BRAT suite. BRAT can also be used in conjunction with Matlab/IDL (via reading routines) or in C/C++/Fortran via a programming API, allowing the user to obtain desired data, bypassing the data-formatting hassle. BRAT can be used simply to visualise data quickly, or to translate the data into other formats such as netCDF, ASCII text files, KML (Google Earth

  3. SAR/MTI on small airborne platforms

    NARCIS (Netherlands)

    Rossum, W.L. van; Vermeulen, B.C.B.

    2006-01-01

    A small SAR-MTI system is being developed at TNO, aimed at deployment on tactical UAV. The system makes use of modern front-end technology, to provide flexible SAR imaging and MTI modes. Major design goals are 50 kg weight, 500 W power consumption and 50 cm resolution in order to comply with typical

  4. PHARUS: A C-band Airborne SAR

    NARCIS (Netherlands)

    Hoogeboom, P.; Koomen, P.J.; Pouwels, H.; Snoeij, P.

    1990-01-01

    In The Netherlands a plan to design aircraft and build a polarimetric C-band SAR system of a novel design, called PHARUS (PHased Array Universal SAR) is carried out by three institutes. These institutes are the Physics and Electronics Laboratory TNO in The Hague (prime contractor and project managem

  5. Thermal Analysis of the Chinese SAR Antenna

    Science.gov (United States)

    Ma, Huitao; Jiang, Hai; Liu, Qiang

    2002-01-01

    success or failure of the mission directly. In general, the SAR Antenna is very large, about 9500mm×4000mm in the deployed configuration. The SAR Antenna system is also very complicated, consisting of 5 antenna panels, deployment mechanism, hinges, tie-downs, extendible support structure and drivers. complicated space heat fluxes( the solar radiation, earth IR and albedo) and so on. However, the SAR Antenna in the orbital flying is directly exposed to the bad space environment. If the thermal design is not correct, the unreasonable temperature distribution of the SAR Antenna will be resulted in, which maybe causes too large thermal deformation to ensure the normal deployment and operation performance of the SAR Antenna. So it is necessary to conduct the thermal design for the SAR Antenna. respectively. The temperature distributions and the worst gradients of the SAR Antenna were obtained in the different cases. These results provide an important theoretic reference for the thermal design of the SAR Antenna. Based on the thermal analysis, some important conclusions are obtained. the software NEVADA and SINDA/G.

  6. PHARUS: Airborne SAR Development in the Netherlands

    NARCIS (Netherlands)

    Hoogeboom, P.; Koomen, P.J.; Snoeij, P.; Pouwels, H.

    1992-01-01

    The PHARUS project (PHARUS stands for Phased Array Universal SAR) aims for a polarimetric C-band aircraft SAR that will be finalized in 1994. The system will make use of a phased array antenna with solid state amplifiers. The project consists of two phases, a definition phase and a realization phase

  7. SAR Speckle Noise Reduction Using Wiener Filter

    Science.gov (United States)

    Joo, T. H.; Held, D. N.

    1983-01-01

    Synthetic aperture radar (SAR) images are degraded by speckle. A multiplicative speckle noise model for SAR images is presented. Using this model, a Wiener filter is derived by minimizing the mean-squared error using the known speckle statistics. Implementation of the Wiener filter is discussed and experimental results are presented. Finally, possible improvements to this method are explored.

  8. Advanced antennas for SAR spacecraft

    Science.gov (United States)

    Gail, William B.

    1993-01-01

    Single and multi-frequency antenna concepts were developed to evaluate the feasibility of building large aperture polarimetric synthetic aperture radar (SAR) systems to be launched in low cost vehicles such as the Delta 2. The antennas are 18.9 m long by 2.6 m wide (L-band) and achieve single polarization imaging to an incidence angle of 55 degrees and dual/quad imaging to 42 degrees. When combined with strawman spacecraft designs, both concepts meet the mass and volume constraints imposed by a Delta 2 launch.

  9. 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.

  10. Identification of a novel conserved HLA-A*0201-restricted epitope from the spike protein of SARS-CoV

    Directory of Open Access Journals (Sweden)

    Ni Bing

    2009-12-01

    Full Text Available Abstract Background The spike (S protein is a major structural glycoprotein of coronavirus (CoV, the causal agent of severe acute respiratory syndrome (SARS. The S protein is a potent target for SARS-specific cell-mediated immune responses. However, the mechanism CoV pathogenesis in SARS and the role of special CTLs in virus clearance are still largely uncharacterized. Here, we describe a study that leads to the identification of a novel HLA-A*0201-restricted epitope from conserved regions of S protein. Results First, different SARS-CoV sequences were analyzed to predict eight candidate peptides from conserved regions of the S protein based upon HLA-A*0201 binding and proteosomal cleavage. Four of eight candidate peptides were tested by HLA-A*0201 binding assays. Among the four candidate peptides, Sp8 (S958-966, VLNDILSRL induced specific CTLs both ex vivo in PBLs of healthy HLA-A2+ donors and in HLA-A2.1/Kb transgenic mice immunized with a plasmid encoding full-length S protein. The immunized mice released IFN-γ and lysed target cells upon stimulation with Sp8 peptide-pulsed autologous dendritic cells in comparison to other candidates. Conclusion These results suggest that Sp8 is a naturally processed epitope. We propose that Sp8 epitope should help in the characterization of mechanisms of virus control and immunopathology in SARS-CoV infection.

  11. Functional genomics highlights differential induction of antiviral pathways in the lungs of SARS-CoV-infected macaques.

    Directory of Open Access Journals (Sweden)

    Anna de Lang

    2007-08-01

    Full Text Available The pathogenesis of severe acute respiratory syndrome coronavirus (SARS-CoV is likely mediated by disproportional immune responses and the ability of the virus to circumvent innate immunity. Using functional genomics, we analyzed early host responses to SARS-CoV infection in the lungs of adolescent cynomolgus macaques (Macaca fascicularis that show lung pathology similar to that observed in human adults with SARS. Analysis of gene signatures revealed induction of a strong innate immune response characterized by the stimulation of various cytokine and chemokine genes, including interleukin (IL-6, IL-8, and IP-10, which corresponds to the host response seen in acute respiratory distress syndrome. As opposed to many in vitro experiments, SARS-CoV induced a wide range of type I interferons (IFNs and nuclear translocation of phosphorylated signal transducer and activator of transcription 1 in the lungs of macaques. Using immunohistochemistry, we revealed that these antiviral signaling pathways were differentially regulated in distinctive subsets of cells. Our studies emphasize that the induction of early IFN signaling may be critical to confer protection against SARS-CoV infection and highlight the strength of combining functional genomics with immunohistochemistry to further unravel the pathogenesis of SARS.

  12. History of SAR at Lockheed Martin (previously Goodyear Aerospace)

    Science.gov (United States)

    Lasswell, Stephen W.

    2005-05-01

    Synthetic Aperture Radar (SAR) was invented by Carl Wiley at Goodyear Aircraft Company in Goodyear, Arizona, in 1951. From that time forward, as the company became Goodyear Aerospace Corporation, Loral Corporation, and finally Lockheed Martin Corporation, the Arizona employees past and present played a long and storied role in numerous SAR firsts. These include the original SAR patent (known as Simultaneous Doppler Buildup), the first demonstration SAR and flight test, the first operational SAR system, the first operational SAR data link, the first 5-foot resolution operational SAR system, the first 1-foot resolution SAR system, and the first large scale SAR digital processor. The company has installed and flown over five hundred SAR systems on more than thirty different types of aircraft for numerous countries throughout the world. The company designed and produced all of the evolving high performance SAR systems for the U. S. Air Force SR-71 "Blackbird" spy plane throughout its entire operational history, spanning some twenty-nine years. Recent SAR accomplishments include long-range standoff high performance SAR systems, smaller high resolution podded SAR systems for fighter aircraft, and foliage penetration (FOPEN) SAR. The company is currently developing the high performance SAR/MTI (Moving Target Indication) radar for the Army Aerial Common Sensor (ACS) system.

  13. Antenna motion errors in bistatic SAR imagery

    Science.gov (United States)

    Wang, Ling; Yazıcı, Birsen; Cagri Yanik, H.

    2015-06-01

    Antenna trajectory or motion errors are pervasive in synthetic aperture radar (SAR) imaging. Motion errors typically result in smearing and positioning errors in SAR images. Understanding the relationship between the trajectory errors and position errors in reconstructed images is essential in forming focused SAR images. Existing studies on the effect of antenna motion errors are limited to certain geometries, trajectory error models or monostatic SAR configuration. In this paper, we present an analysis of position errors in bistatic SAR imagery due to antenna motion errors. Bistatic SAR imagery is becoming increasingly important in the context of passive imaging and multi-sensor imaging. Our analysis provides an explicit quantitative relationship between the trajectory errors and the positioning errors in bistatic SAR images. The analysis is applicable to arbitrary trajectory errors and arbitrary imaging geometries including wide apertures and large scenes. We present extensive numerical simulations to validate the analysis and to illustrate the results in commonly used bistatic configurations and certain trajectory error models.

  14. SARS - infectious disease of 21st century

    Directory of Open Access Journals (Sweden)

    Tjandra Y. Aditama

    2005-03-01

    Full Text Available Severe acute respiratory syndrome (SARS is an emerging viral infectious disease. According to the World Health Organization, a suspected case of SARS is defined as documented fever (temperature >38°C, lower respiratory tract symptoms, and contact with a person believed to have had SARS or history of travel to an area of documented transmission. A probable case is a suspected case with chest radiographic findings of pneumonia, acute respiratory distress syndrome (ARDS, or an unexplained respiratory illness resulting in death, with autopsy findings of ARDS without identifiable cause. In this article some SARS epidemiological data in Indonesia will also presented. There are 7 SARS suspected cases and 2 probable cases were registered in Indonesia on the period of 1 March to 9 July 2003, and no more cases were reported after that time. How will be SARS progression in the future will be a subject of discussion among scientist, and we will have to wait and be prepared for any development might occur. (Med J Indones 2005; 14: 59-63Keywords: SARS, Case Definition, Etiology, Indonesia

  15. 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...

  16. 9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ... Virus. 113.211 Section 113.211 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.211 Feline Rhinotracheitis Vaccine, Killed Virus....

  17. 9 CFR 113.205 - Newcastle Disease Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ... Virus. 113.205 Section 113.205 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.205 Newcastle Disease Vaccine, Killed Virus. Newcastle Disease...

  18. 9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ... Virus. 113.210 Section 113.210 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.210 Feline Calicivirus Vaccine, Killed Virus. Feline...

  19. 9 CFR 113.216 - Bovine Rhinotracheitis Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ... Virus. 113.216 Section 113.216 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.216 Bovine Rhinotracheitis Vaccine, Killed Virus. Infectious...

  20. 9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ... Virus. 113.203 Section 113.203 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.203 Feline Panleukopenia Vaccine, Killed Virus. Feline...

  1. 9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ..., Killed Virus. 113.208 Section 113.208 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.208 Avian Encephalomyelitis Vaccine, Killed Virus....

  2. DInSAR Processing with Polarimetric Data Procesado DinSAR con datos polarimetricos Processament DInSAR amb dades polarimètriques

    OpenAIRE

    Monells Miralles, Daniel

    2011-01-01

    English: Study of the uses of orbital polarimetric data for the survey of terrain subsidence through SAR Differential interferometry (DInSAR). Castellano: Estudio del uso de datos polarimetricos orbitales para la monitorizació de la subsidencia del terreno mediante Interferometría Diferencial SAR (DInSAR) Català: Estudi de l'ús de dades polarimetriques orbitals per la monitorització de la subsidència del terreny mitjançant Interferometria diferencial SAR (DInSAR).

  3. Outdoor RCS Measurement Range for Spaceborne SAR Calibration Targets

    OpenAIRE

    Döring, Björn; Schwerdt, Marco; Bauer, Robert

    2007-01-01

    The Microwaves and Radar Institute regularly performs calibration campaigns for spaceborne synthetic aperture radar (SAR) systems, among which have been X-SAR, SRTM, and ASAR. Tight performance specifications for future spaceborne SAR systems like TerraSAR-X and TanDEM-X demand an absolute radiometric accuracy of better than 1 dB. The relative and absolute radiometric calibration of SAR systems depends on reference point targets (i. e. passive corner reflectors and active transponders), which...

  4. SAR ATR Based on Convolutional Neural Network

    Directory of Open Access Journals (Sweden)

    Tian Zhuangzhuang

    2016-06-01

    Full Text Available This study presents a new method of Synthetic Aperture Radar (SAR image target recognition based on a convolutional neural network. First, we introduce a class separability measure into the cost function to improve this network’s ability to distinguish between categories. Then, we extract SAR image features using the improved convolutional neural network and classify these features using a support vector machine. Experimental results using moving and stationary target acquisition and recognition SAR datasets prove the validity of this method.

  5. Analysis of Resolution of Bistatic SAR

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper, the spatial resolutions at different directions of bistatic synthetic aperture radar (BiSAR) have been derived from the ambiguity function. Compared with monostatic signal to noise ratio, BiSAR's resolutions of a fixed point target are varying with slow time since BiSAR system is space-variant. Constraints for the assumption of space-invariant bistatic topology are proposed in the paper. Moreover, under the assumption of invariance, the change of resolutions at different point in the image scene is taken into account, and we have specified two key parameters that affect resolutions directly and analyzed the way how they influence on the resolutions.

  6. SAR observations of coastal zone conditions

    Science.gov (United States)

    Meadows, G. A.; Kasischke, E. S.; Shuchman, R. A.

    1980-01-01

    Applications of Synthetic Aperture Radar (SAR) technology to the observation of coastal zones phenomena are detailed. The conditions observed include gravity wave detection, surf zone location, surface currents, and long-period 'surf beats'. Algorithms have been developed and successfully tested that determine significant wave and current parameters from the sea surface backscatter of microwave energy. Doppler information from the SAR optical correlator allows a rough estimation of near shore surface flow velocities that has been found in agreement with both theory and in situ observations as well. Seasat SAR data of the Scotland and North Carolina coasts are considered, as well as the results of bathymetric updating of coastal area charts.

  7. EFSA AHAW Panel (EFSA Panel on Animal Health and Welfare), ECDC (European Centre for Disease Prevention and Control) and EMA (European Medicines Agency), 2013. Scientific Opinion on the possible risks posed by the Influenza A(H3N2v) virus for animal health and its potential spread and implications for animal and human health

    DEFF Research Database (Denmark)

    Bøtner, Anette

    pandemic virus were reported in the United States (US). The likelihood of introduction of H3N2v virus into the EU, and subsequent exposure and infection of EU pig herds was assessed. The overall likelihood of a pig holding in the EU being infected by exposure to H3N2v virus through either imported...... of respiratory nature and follows a relatively mild course with fever, coughing and inappetence, similar to that of the endemic swine influenza viruses. Immunity resulting from vaccination with European vaccines may provide some cross-protection against infection with H3N2v virus whereas vaccines based on US...

  8. The effect of maternal antibodies on the detection of bovine virus diarrhoea virus in peripheral blood samples

    NARCIS (Netherlands)

    Zimmer, G.M.; Maanen, van C.; Goey, de I.; Brinkhof, J.; Wentink, G.H.

    2004-01-01

    Persistently infected animals (PI animals), that is those animals born after an intrauterine infection of the dam during the first 120 days of gestation, are the main source of bovine virus diarrhoea virus (BVD virus) in a cattle population. The success of any BVD virus eradication programme depends

  9. Similarity measures of full polarimetric SAR images fusion for improved SAR image matching

    Science.gov (United States)

    Ding, H.

    2015-06-01

    China's first airborne SAR mapping system (CASMSAR) developed by Chinese Academy of Surveying and Mapping can acquire high-resolution and full polarimetric (HH, HV, VH and VV) Synthetic aperture radar (SAR) data. It has the ability to acquire X-band full polarimetric SAR data at a resolution of 0.5m. However, the existence of speckles which is inherent in SAR imagery affects visual interpretation and image processing badly, and challenges the assumption that conjugate points appear similar to each other in matching processing. In addition, researches show that speckles are multiplicative speckles, and most similarity measures of SAR image matching are sensitive to them. Thus, matching outcomes of SAR images acquired by most similarity measures are not reliable and with bad accuracy. Meanwhile, every polarimetric SAR image has different backscattering information of objects from each other and four polarimetric SAR data contain most basic and a large amount of redundancy information to improve matching. Therefore, we introduced logarithmically transformation and a stereo matching similarity measure into airborne full polarimetric SAR imagery. Firstly, in order to transform the multiplicative speckles into additivity ones and weaken speckles' influence on similarity measure, logarithmically transformation have to be taken to all images. Secondly, to prevent performance degradation of similarity measure caused by speckles, measure must be free or insensitive of additivity speckles. Thus, we introduced a stereo matching similarity measure, called Normalized Cross-Correlation (NCC), into full polarimetric SAR image matching. Thirdly, to take advantage of multi-polarimetric data and preserve the best similarity measure value, four measure values calculated between left and right single polarimetric SAR images are fused as final measure value for matching. The method was tested for matching under CASMSAR data. The results showed that the method delivered an effective

  10. Atmosphere Observations by Geosynchronous SARs

    Science.gov (United States)

    Monti guarnieri, Andrea; Rocca, Fabio; Wadge, Geoff; Schulz, Detlef

    2014-05-01

    We analyze different geosynchronous Synthetic Aperture RADAR concepts aimed to get both tropospheric and ionospheric delay maps with a revisit time of minutes and sub-continental coverage. Such products could be used either to compensate the delay in LEO-SAR missions and GNSS, or to generate integrated water-vapor maps to be used for Numerical Weather Forecast. The system exploits the principle of RADAR location, by transmitting a pulse with a suitable bandwidth, and the residual non-zero eccentricity of COMmunication SATellites. Different concepts are proposed as payload in COMSAT, or constellations of small satellites, that is monostatic or bistatic/multistatic RADARS. The selection of the best frequency, from L to Ku, and the analysis of performances is presented.

  11. Evaluation of InSAR and TomoSAR for Monitoring Deformations Caused by Mining in a Mountainous Area with High Resolution Satellite-Based SAR

    Directory of Open Access Journals (Sweden)

    Donglie Liu

    2014-02-01

    Full Text Available Interferometric Synthetic Aperture Radar (InSAR and Differential Interferometric Synthetic Aperture Radar (DInSAR have shown numerous applications for subsidence monitoring. In the past 10 years, the Persistent Scatterer InSAR (PSI and Small BAseline Subset (SBAS approaches were developed to overcome the problem of decorrelation and atmospheric effects, which are common in interferograms. However, DInSAR or PSI applications in rural areas, especially in mountainous regions, can be extremely challenging. In this study we have employed a combined technique, i.e., SBAS-DInSAR, to a mountainous area that is severely affected by mining activities. In addition, L-band (ALOS and C-band (ENVISAT data sets, 21 TerraSAR-X images provided by German Aerospace Center (DLR with a high resolution have been used. In order to evaluate the ability of TerraSAR-X for mining monitoring, we present a case study of TerraSAR-X SAR images for Subsidence Hazard Boundary (SHB extraction. The resulting data analysis gives an initial evaluation of InSAR applications within a mountainous region where fast movements and big phase gradients are common. Moreover, the experiment of four-dimension (4-D Tomography SAR (TomoSAR for structure monitoring inside the mining area indicates a potential near all-wave monitoring, which is an extension of conventional InSAR.

  12. SARS冠状病毒的病原生物学分析及其启示%Analysis of pathogenic biology of SARS - associated coronavirus and its implication

    Institute of Scientific and Technical Information of China (English)

    曾耀英

    2003-01-01

    Severe acute respiratory syndrome (SARS) is the first new epidemic of the twenty - first century. A novel coronavirus (SARS - CoV) has been identified as the causative agent of SAP, S. The genome of SARS - CoV has 29,727 nucleatides in length. The genome organization, with 11 open reading flames, is similar to that of conronaviruses.Phylogenetic analyses and sequence comparisons showed that SARS- CoV is not closely related to any of the known coronaviruses, indicating neither a mutant nor recombinant of well -characterized coronaviruses. It is a complete new coronavirus from nonhuman hostPathological studies show that severe immune response, associated to cytokine dysregulation, may be related to the lung damage of fatal SRAS. Recombination of genomes of wild - type strains with vaccine coronavirus is a potential risk associated with the application of living attenuated coronavirus vaccines. The proteinases, controlling the activities of the SARS- CoV replication, and spike protein, involved in viral entry and pathogenesis, represent attractive targets of anti- SARS drug development. Comparative full-length genome sequence analysis of 14 SARS coronavirus isolates suggests a remarkable genetic conservation of the virus. Anti - SARS vaccine and drug development will benefit from this genetic conservation. SARS-CoV is not likely to change rapidly and thus may not readily mutate to a benign infection. The progress in anti - SARS research has been impressive. However, one of the most effective tools in the control of the SARS is quickly tracing and isolating the contacts of stricken patients before they spread the virus further.

  13. 9 CFR 117.6 - Removal of animals.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Removal of animals. 117.6 Section 117.6 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS ANIMALS AT LICENSED...

  14. 9 CFR 117.3 - Admittance of animals.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Admittance of animals. 117.3 Section 117.3 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS ANIMALS AT...

  15. 9 CFR 117.5 - Segregation of animals.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Segregation of animals. 117.5 Section 117.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS ANIMALS AT...

  16. Polarimetric SAR Interferometry Evaluation in Mangroves

    Science.gov (United States)

    Lee, Seung-Kuk; Fatoyinbo,Temilola; Osmanoglu, Batuhan; Sun, Guoqing

    2014-01-01

    TanDEM-X (TDX) enables to generate an interferometric coherence without temporal decorrelation effect that is the most critical factor for a successful Pol-InSAR inversion, as have recently been used for forest parameter retrieval. This paper presents mangrove forest height estimation only using single-pass/single-baseline/dual-polarization TDX data by means of new dual-Pol-InSAR inversion technique. To overcome a lack of one polarization in a conventional Pol- InSAR inversion (i.e. an underdetermined problem), the ground phase in the Pol-InSAR model is directly estimated from TDX interferograms assuming flat underlying topography in mangrove forest. The inversion result is validated against lidar measurement data (NASA's G-LiHT data).

  17. Statistical Modeling of SAR Images: A Survey

    Directory of Open Access Journals (Sweden)

    Gui Gao

    2010-01-01

    Full Text Available Statistical modeling is essential to SAR (Synthetic Aperture Radar image interpretation. It aims to describe SAR images through statistical methods and reveal the characteristics of these images. Moreover, statistical modeling can provide a technical support for a comprehensive understanding of terrain scattering mechanism, which helps to develop algorithms for effective image interpretation and creditable image simulation. Numerous statistical models have been developed to describe SAR image data, and the purpose of this paper is to categorize and evaluate these models. We first summarize the development history and the current researching state of statistical modeling, then different SAR image models developed from the product model are mainly discussed in detail. Relevant issues are also discussed. Several promising directions for future research are concluded at last.

  18. Formation Flying for Distributed InSAR

    Science.gov (United States)

    Scharf, Daniel P.; Murray, Emmanuell A.; Ploen, Scott R.; Gromov, Konstantin G.; Chen, Curtis W.

    2006-01-01

    We consider two spacecraft flying in formation to create interferometric synthetic aperture radar (InSAR). Several candidate orbits for such in InSar formation have been previously determined based on radar performance and Keplerian orbital dynamics. However, with out active control, disturbance-induced drift can degrade radar performance and (in the worst case) cause a collision. This study evaluates the feasibility of operating the InSAR spacecraft as a formation, that is, with inner-spacecraft sensing and control. We describe the candidate InSAR orbits, design formation guidance and control architectures and algorithms, and report the (Delta)(nu) and control acceleration requirements for the candidate orbits for several tracking performance levels. As part of determining formation requirements, a formation guidance algorithm called Command Virtual Structure is introduced that can reduce the (Delta)(nu) requirements compared to standard Leader/Follower formation approaches.

  19. Advanced Antenna for Digital Beamforming SAR Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop a wideband (500 MHz) L-band phased-array antenna for airborne Synthetic Aperture Radar (SAR) applications based on a novel approach that will make possible...

  20. IMPROVED ALGORITHM FOR STRIPMAP SAR IMAGING

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper proposes a calibrated method for quasi-broadside side-looking mode SAR imaging with small squint angle and an improved method named as phase alignment algorithm of subaperture reference signal. The calibrated method adopts subaperture spotlighting algorithm of broadside mode to image the real data of quasi-broadside mode SAR, then based on the obtained image the small squint angle is estimated and the calibrated subaperture spotlighting algorithm of squint mode is employed to obtain the final image. The calibrated method can calibrate the abnormal region and obtain the correct image. The phase alignment algorithm of subaperture reference signal adjusts phases of respective subaperture reference signals in order to make them be in phase and constructs a new spotlighting window function for SAR imaging. Theoretical analysis shows that with the same sample data, the improved method can increase SAR imaging area in azimuth dimension. The methods are verified by the results of computer simulation.

  1. Optimal Approach to SAR Image Despeckling

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Speckle filtering of synthetic aperture radar (SAR) images while preserving the spatial signal variability (texture and fine structures) still remains a challenge. Many algorithms have been proposed for the SAR imagery despeckling. However,simulated annealing (SA) method is one of excellent choices currently. A critical problem in the study on SA is to provide appropriate cooling schedules that ensure fast convergence to near-optimal solutions. This paper gives a new necessary and sufficient condition for the cooling schedule so that the algorithm state converges in all probability to the set of globally minimum cost states.Moreover, it constructs an appropriate objective function for SAR image despeckling. An experimental result of the actual SAR image processing is obtained.

  2. Serum Neutralization Assay Can Efficiently Replace Plaque Reduction Neutralization Test for Detection and Quantitation of West Nile Virus Antibodies in Human and Animal Serum Samples

    Science.gov (United States)

    Di Gennaro, Annapia; Casaccia, Claudia; Conte, Annamaria; Monaco, Federica; Savini, Giovanni

    2014-01-01

    A serum neutralization assay (SN) was compared with the official plaque reduction neutralization test for the quantitation of West Nile virus antibodies. A total of 1,348 samples from equid sera and 38 from human sera were tested by these two methods. Statistically significant differences were not observed, thus supporting the use of SN for routine purposes. PMID:25100824

  3. " Animal, trop animal "

    OpenAIRE

    Potestà, Andréa

    2010-01-01

    Dans la tradition philosophique, on trouve plusieurs définitions de l’homme. La célèbre définition aristotélicienne, zoon logon echon (animal doué du langage ou animal rationnel) fournit le paradigme ainsi que la méthode de toutes les définitions successives. Il s’agit d’ajouter au vivant, à l’animal, quelque chose d’autre, quelque chose de plus, qui permette de le caractériser et le fasse entendre comme différent des bêtes. Cette diversité peut être conçue différemment : en tant qu’élévation...

  4. SAR ATR Based on Convolutional Neural Network

    OpenAIRE

    Tian Zhuangzhuang; Zhan Ronghui; Hu Jiemin; Zhang Jun

    2016-01-01

    This study presents a new method of Synthetic Aperture Radar (SAR) image target recognition based on a convolutional neural network. First, we introduce a class separability measure into the cost function to improve this network’s ability to distinguish between categories. Then, we extract SAR image features using the improved convolutional neural network and classify these features using a support vector machine. Experimental results using moving and stationary target acquisition and recogni...

  5. Ambiguities and Image Quality in Staggered SAR

    OpenAIRE

    Villano, Michelangelo; Krieger, Gerhard; Moreira, Alberto

    2015-01-01

    Staggered SAR is an innovative synthetic aperture radar (SAR) concept, where the pulse repetition interval (PRI) is continuously varied. This, together with digital beamforming (DBF) in elevation, allows high-resolution imaging of a wide continuous swath without the need for a long antenna with multiple azimuth apertures. As an additional benefit, the energy of range and azimuth ambiguities is spread over large areas: Ambiguities therefore appear in the image as a noise-like disturbance rathe...

  6. A revised radiometric normalisation standard for SAR

    OpenAIRE

    Small, D.; N. Miranda; Meier, E

    2009-01-01

    Improved geometric accuracy in SAR sensors implies that more complex models of the Earth may be used not only to geometrically rectify imagery, but also to more robustly calibrate their radiometry. Current beta, sigma, and gamma nought SAR radiometry conventions all assume a simple “flat as Kansas” Earth ellipsoid model. We complement these simple models with improved radiometric calibration that accounts for local terrain variations. In the era of ERS-1 and RADARSAT-1, image geolocation a...

  7. Cynomolgus macaque as an animal model for severe acute respiratory syndrome.

    Directory of Open Access Journals (Sweden)

    James V Lawler

    2006-05-01

    Full Text Available BACKGROUND: The emergence of severe acute respiratory syndrome (SARS in 2002 and 2003 affected global health and caused major economic disruption. Adequate animal models are required to study the underlying pathogenesis of SARS-associated coronavirus (SARS-CoV infection and to develop effective vaccines and therapeutics. We report the first findings of measurable clinical disease in nonhuman primates (NHPs infected with SARS-CoV. METHODS AND FINDINGS: In order to characterize clinically relevant parameters of SARS-CoV infection in NHPs, we infected cynomolgus macaques with SARS-CoV in three groups: Group I was infected in the nares and bronchus, group II in the nares and conjunctiva, and group III intravenously. Nonhuman primates in groups I and II developed mild to moderate symptomatic illness. All NHPs demonstrated evidence of viral replication and developed neutralizing antibodies. Chest radiographs from several animals in groups I and II revealed unifocal or multifocal pneumonia that peaked between days 8 and 10 postinfection. Clinical laboratory tests were not significantly changed. Overall, inoculation by a mucosal route produced more prominent disease than did intravenous inoculation. Half of the group I animals were infected with a recombinant infectious clone SARS-CoV derived from the SARS-CoV Urbani strain. This infectious clone produced disease indistinguishable from wild-type Urbani strain. CONCLUSIONS: SARS-CoV infection of cynomolgus macaques did not reproduce the severe illness seen in the majority of adult human cases of SARS; however, our results suggest similarities to the milder syndrome of SARS-CoV infection characteristically seen in young children.

  8. Ionospheric Specifications for SAR Interferometry (ISSI)

    Science.gov (United States)

    Pi, Xiaoqing; Chapman, Bruce D; Freeman, Anthony; Szeliga, Walter; Buckley, Sean M.; Rosen, Paul A.; Lavalle, Marco

    2013-01-01

    The ISSI software package is designed to image the ionosphere from space by calibrating and processing polarimetric synthetic aperture radar (PolSAR) data collected from low Earth orbit satellites. Signals transmitted and received by a PolSAR are subject to the Faraday rotation effect as they traverse the magnetized ionosphere. The ISSI algorithms combine the horizontally and vertically polarized (with respect to the radar system) SAR signals to estimate Faraday rotation and ionospheric total electron content (TEC) with spatial resolutions of sub-kilometers to kilometers, and to derive radar system calibration parameters. The ISSI software package has been designed and developed to integrate the algorithms, process PolSAR data, and image as well as visualize the ionospheric measurements. A number of tests have been conducted using ISSI with PolSAR data collected from various latitude regions using the phase array-type L-band synthetic aperture radar (PALSAR) onboard Japan Aerospace Exploration Agency's Advanced Land Observing Satellite mission, and also with Global Positioning System data. These tests have demonstrated and validated SAR-derived ionospheric images and data correction algorithms.

  9. 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

  10. UAVSAR: InSAR and PolSAR Test Bed for the Proposed NI-SAR Mission

    Science.gov (United States)

    Jones, C. E.; Hensley, S.; Lou, Y.

    2014-12-01

    UAVSAR, which first became operational in 2009, has served as an operational testbed for the NI-SAR L-band radar concept and a unique instrument in its own right. UAVSAR supports a broad array of basic and applied geoscience, covering on smaller scale all the disciplines NI-SAR would be able to address on a global scale. Although designed specifically to provide high accuracy repeated flight tracks and precise imaging geometry for InSAR-based solid earth studies, its fully polarimetric operation, low noise, and consistent calibration accuracy has made it a premier instrument for PolSAR-based studies also. Since 2009 it has successfully imaged more than 16 million km2 and >4300 quad-polarimetric data products are now publicly available online. Upgrades made in the last year to automate the repeat track processing serve as a model for generating large volumes of InSAR products: Since January 2014 more than 700 interferometric products have been released, exceeding the output of all previous years combined. Standardly available products now include browse images of all InSAR acquisitions and coregistered single-look complex image stacks suitable for standard time series analysis. Here we present an overview of the wide range of studies utilizing UAVSAR data including those based on polarimetry and pair-wise and times series interferometry, highlighting both the unique capabilities of UAVSAR and the ways in which NI-SAR would be able to dramatically extend the capabilities. This research was conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

  11. 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...

  12. Absence of cytotoxic antibody to human immunodeficiency virus-infected cells in humans and its induction in animals after infection or immunization with purified envelope glycoprotein gp120.

    OpenAIRE

    Nara, P L; Robey, W G; Gonda, M A; Carter, S G; Fischinger, P J

    1987-01-01

    The presence of antibody-dependent complement-mediated cytotoxicity (ACC) was assessed in humans and chimpanzees, which are capable of infection with human immunodeficiency virus isolate HTLV-IIIb, and examined in the goat after immunization with the major viral glycoprotein (gp120) of HTLV-IIIb. In infected humans no antibody mediating ACC was observed regardless of the status of disease. Even healthy individuals with high-titer, broadly reactive, neutralizing antibodies had no ACC. In contr...

  13. 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...

  14. Identification of an HLA-A* 0201-restricted CD8+ T-cell epitope SSp-1 of SARS-CoV spike protein

    Institute of Scientific and Technical Information of China (English)

    Wang B; Yu Y; Wang X; Yang R; Cao X; Chen H; Jiang X; Zhang M; Wan T; Li N; Zhou X; Wu Y; Yang F

    2004-01-01

    A novel coronavirus, severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV), has been identified as the causal agent of SARS. Spike (S) protein is a major structural glycoprotein of the SARS virus and a potential target for SARS-specific cell-mediated immune responses. A panel of S protein-derived peptides was tested for their binding affinity to HLA-A * 0201 molecules. Peptides with high affinity for HLA-A * 0201 were then assessed for their capacity to elicit specific immune responses mediated by cytotoxic T lymphocytes (CTLs) both in vivo, in HLA-A2. 1/Kb transgenic mice, and in vitro, from peripheral blood lymphocytes (PBLs) harvested from healthy HLA-A2.1 + donors. SARS-CoV protein-derived peptide-1 (SSp-1 RLNEVAKNL), induced peptide-specific CTLs both in vivo (transgenic mice) and in vitro (human PBLs), which specifically released interferon-gamma (IFN-gamma) upon stimulation with SSp-1-pulsed autologous dendritic cells (DCs) or T2 cells. SSp-1-specific CTLs also lysed major histocompatibility complex (MHC)-matched tumor cell lines engineered to express S proteins. HLA-A * 0201-SSp-1 tetramer staining revealed the presence of significant populations of SSp-1-specific CTLs in SSp-1-induced CD8+ T cells. We propose that the newly identified epitope SSp-1 will help in the characterization of virus control mechanisms and immunopathology in SARS-CoV infection, and may be relevant to the development of immunotherapeutic approaches for SARS.

  15. Landslide Monitoring in Three Gorges Area Using D-InSAR and PS-InSAR

    Science.gov (United States)

    Tantianuparp, Peraya; Shi, Xuguo; Liao, Mingsheng; Zhang, Lu; Balz, Timo

    2013-01-01

    Landslides are a major hazard in steep mountainous area, like the Three Gorges area. The Three Gorges dam was built on a geologically unstable zone. The geological pressures from the rising water level caused by the dam and the deforestation have further increased the possibility for landslides in the area. Many landslide monitoring techniques are applied to analysis, forecast, and control landslides in this area. D-InSAR and PS-InSAR, the time series InSAR analysis, are used for terrain motion detection and to estimate displacement trends. In this paper, SAR data from systems with different wavelengths, like the C-band ASAR, the L-band PALSAR, and the high-resolution TerraSAR-X X-band data, are used.

  16. Detection and analysis of rabies street virus in animals in China%我国各地区动物狂犬病街毒的检测及分析

    Institute of Scientific and Technical Information of China (English)

    徐葛林; 严家新; 张永振; 董关木; 唐建蓉; 杨晓明; 孟胜利; 吴杰; 肖奇友; 周敦金; 朱凤才; 王萍; 王定明; 明平刚

    2008-01-01

    目的 检测我国不同地区动物中狂犬病毒带毒率并分析糖蛋白编码基因序列.方法 El.ISA、免疫荧光法分别检测586份采集自中国不同地区的犬、猫,蝙蝠和野鼠脑标本和16份犬唾液中狂犬病街毒,阳性标本乳鼠颅内接种.并测序.结果 ELISA、免疫荧光法均在犬脑中分离到10株狂犬病街毒,其中贵州省113份犬脑中分离到2株病毒,湖南省62份犬脑中分离到2株病毒,武汉市70份犬脑中分离到2株病毒,江苏省85份犬脑中分离到4株病毒,沈阳市69份犬脑中未分离到狂犬病毒;79份猫脑、100份蝙蝠脑及8份鼠脑中未检出狂犬病街毒,16份犬唾液标本未检出狂犬病毒.在贵州省和武汉市,冬季采集的112份犬脑末检出狂犬病毒.春夏季采集的40份犬脑中,4份阳性.分离的10株狂犬病毒阳性株颅内接种乳鼠后.均发病死亡.所有分离株均属狂犬病毒基因1型,可分为4个亚组.结论 同一地区的狂犬病毒分离株以及相邻省份的狂犬病毒分离株的同源性十分接近,动物样本采集时间与狂犬病毒阳检率有关.%Objective To detect the positive rate of rabies virus in animals of different regions in China and to analyze the sequences of glycoprotein encoding gene.Methods Rabies street viruses were detected in 586 brain samples of dogs,cats,bats,mice and 16 saliva samples of dogs from different regions in China using enzyme-linked immunosorbent assay(ELISA)and immunofluorescent assay (IFA).Positive samples were inoculated intracranially to neonate rats and then sequenced.Results Ten street virus strains were isolated from dog brains using ELISA and IFA,in which 2 positive of 113 in Guizhou Province,2 positive of 62 in Hunan Province,2 positive of 70 in Wuban city,4 positive of 85 in Jiangsu Province,and no positive of 69 in Shenyang city.There was no detectable rabies virus in brains of 79 cats,100 bats,8 mice and in 16 saliva samples.One hundred and twelve brain samples

  17. Investigation of ionospheric effects on SAR Interferometry (InSAR): A case study of Hong Kong

    Science.gov (United States)

    Zhu, Wu; Ding, Xiao-Li; Jung, Hyung-Sup; Zhang, Qin; Zhang, Bo-Chen; Qu, Wei

    2016-08-01

    Synthetic Aperture Radar Interferometry (InSAR) has demonstrated its potential for high-density spatial mapping of ground displacement associated with earthquakes, volcanoes, and other geologic processes. However, this technique may be affected by the ionosphere, which can result in the distortions of Synthetic Aperture Radar (SAR) images, phases, and polarization. Moreover, ionospheric effect has become and is becoming further significant with the increasing interest in low-frequency SAR systems, limiting the further development of InSAR technique. Although some research has been carried out, thorough analysis of ionospheric influence on true SAR imagery is still limited. Based on this background, this study performs a thorough investigation of ionospheric effect on InSAR through processing L-band ALOS-1/PALSAR-1 images and dual-frequency Global Positioning System (GPS) data over Hong Kong, where the phenomenon of ionospheric irregularities often occurs. The result shows that the small-scale ionospheric irregularities can cause the azimuth pixel shifts and phase advance errors on interferograms. Meanwhile, it is found that these two effects result in the stripe-shaped features in InSAR images. The direction of the stripe-shaped effects keep approximately constant in space for our InSAR dataset. Moreover, the GPS-derived rate of total electron content change index (ROTI), an index to reflect the level of ionospheric disturbances, may be a useful indicator for predicting the ionospheric effect for SAR images. This finding can help us evaluate the quality of SAR images when considering the ionospheric effect.

  18. Performance evaluation of SAR/GMTI algorithms

    Science.gov (United States)

    Garber, Wendy; Pierson, William; Mcginnis, Ryan; Majumder, Uttam; Minardi, Michael; Sobota, David

    2016-05-01

    There is a history and understanding of exploiting moving targets within ground moving target indicator (GMTI) data, including methods for modeling performance. However, many assumptions valid for GMTI processing are invalid for synthetic aperture radar (SAR) data. For example, traditional GMTI processing assumes targets are exo-clutter and a system that uses a GMTI waveform, i.e. low bandwidth (BW) and low pulse repetition frequency (PRF). Conversely, SAR imagery is typically formed to focus data at zero Doppler and requires high BW and high PRF. Therefore, many of the techniques used in performance estimation of GMTI systems are not valid for SAR data. However, as demonstrated by papers in the recent literature,1-11 there is interest in exploiting moving targets within SAR data. The techniques employed vary widely, including filter banks to form images at multiple Dopplers, performing smear detection, and attempting to address the issue through waveform design. The above work validates the need for moving target exploitation in SAR data, but it does not represent a theory allowing for the prediction or bounding of performance. This work develops an approach to estimate and/or bound performance for moving target exploitation specific to SAR data. Synthetic SAR data is generated across a range of sensor, environment, and target parameters to test the exploitation algorithms under specific conditions. This provides a design tool allowing radar systems to be tuned for specific moving target exploitation applications. In summary, we derive a set of rules that bound the performance of specific moving target exploitation algorithms under variable operating conditions.

  19. Use of SAR data for proliferation monitoring

    International Nuclear Information System (INIS)

    Synthetic Aperture Radar (SAR) is an active and coherent system. SAR images are complex data which contain both amplitude and phase information. The analysis of single SAR data required a very good experience and a good understanding of SAR geometry regarding layover, shadowing, texture and speckle. Image analyst can depicts and describes most of the facilities related to nuclear proliferation and weapons of mass destruction (WMD). The Amplitude Change Detection (ACD) technique consists of a combination of two or three SAR amplitude data acquired with similar orbit and frequency parameters on different dates. That technique provides a very good overview of the changes and particularly regarding vehicles activity and constructions ongoing within the area of interest over the monitoring period. One of the particularities of the SAR systems is to be coherent. The phase of a single image is not exploitable. Thus when two or more SAR data have been acquired with identical orbit and frequency parameters, the phases shift are indicators of changes such as structural changes, terrain subsidence or motion. The Multi-Temporal Coherence (MTC) product merged the two type of information previously detailed: the ACD and coherence analysis. It consists of the combination of two amplitude images and the corresponding coherence computed image. The MTC image may highlights changes between two states of a target which on the ACD analysis appeared unchanged. EUSC uses the difference interferometry techniques in order to estimate volumes that have changed between two acquisition dates. The paper is followed by the slides of the presentation. (A.C.)

  20. Multiresolution analysis of SAR data

    Science.gov (United States)

    Hummel, Robert

    1993-01-01

    The 'Multiresolution Analysis of SAR Data' program supported research work in five areas. Geometric hashing theory can now be viewed as a Bayesian approach to object recognition. False alarm rates can be greatly reduced by using certain enhancements and modifications developed under this project. Geometric hashing algorithms now exist for the Connection Machine. Recognition of synthetically-produced dot arrays was demonstrated using a model base of 1024 objects. The work represents a substantial advance over existing model-based vision capabilities. Algorithms were developed for determining the translation and rotation of a sensor given only the image flow field data. These are new algorithms, and are much more stable than existing computer vision algorithms for this task. The algorithms might provide independent verification of gyroscopic data, or might be used to compute relative motion with respect to a moving scene object, or may be useful for motion-based segmentation. Our theories explaining the Dempster/Shafer calculus and developing new uncertainty reasoning calculi were extended, and presented at a conference and were incorporated into the Bayesian interpretation of geometric hashing. 'Wavelet Slice Theorem' was developed in several different versions, any of which yields an alternate approach to image formation. The result may well provide a more stable approach to image formation than the standard Fourier-based projection slide theorem, since interpolation of unknown spectra values is better-founded.

  1. Animal Health in Albania

    International Nuclear Information System (INIS)

    The animal health service policy in Albania represents an integral component of overall governmental, social and economic policy in the field of agricultural and rural development, public health, food processing and import/export of animal products. In order to obtain the necessary political, economic and public support, the animal health service attempts to contribute effectively to the overall development of the country which aims at improving the standards of living of its inhabitants. Practical means of contributing to national development include reducing food loses due to animal morbidity and mortality, increasing the productivity of the livestock population, protecting human health against zoonotic diseases and ensuring humane treatment of animals. An animal health strategy contributes to the creation of conditions necessary for uninterrupted animal disease surveillance and control in the country. The main animal health problem in Albania is brucellosis in ruminants, caused by B. melitensis. This infection currently affects the entire country, reaching a prevalence of 10% in several districts. The latest and most severe outbreaks of classical swine fever were identified on 1996 when 5 515 animals were infected and 3 683 animals died. The circulation of bluetongue virus (BTV) was detected for the first time in Albania in 2002 with a seroprevalence of 15%. The evidence of BTV circulation in Albania and the absence of the main vector C. imicola suggest that other Culicoides species could be implicated in virus transmission. H5N1 avian influenza in Albania was confirmed in March 2006 in backyard flocks in the villages of Cuke and Peze-Helmes. In both villages there were no human cases. Rabies was of concern in Albania from 1928 until 1976. The disease re-emerged in March 2001 in the village of Morine in Kukes district affecting a domestic dog and three persons were bitten. Other cases have been reported in northern Albania. (author)

  2. Epidemiology of severe acute respiratory syndrome (SARS): adults and children.

    Science.gov (United States)

    Zhong, Nan-Shan; Wong, Gary W K

    2004-12-01

    Severe acute respiratory syndrome (SARS) is a newly described respiratory infection with pandemic potential. The causative agent is a new strain of coronavirus most likely originating from wild animals. This disease first emerged in November 2002 in Guangdong Province, China. Early in the outbreak the infection had been transmitted primarily via household contacts and healthcare settings. In late February 2003 the infection was transmitted to Hong Kong when an infected doctor from the mainland visited there. During his stay in Hong Kong at least 17 guests and visitors were infected at the hotel at which he stayed. By modern day air travel, the infection was rapidly spread to other countries including Vietnam, Singapore and Canada by these infected guests. With the implementation of effective control strategies including early isolation of suspected cases, strict infection control measures in the hospital setting, meticulous contact tracing and quarantine, the outbreak was finally brought under control by July 2003. In addition, there were another two events of SARS in China between the end of December 2003 and January 2004 and from March to May 2004; both were readily controlled without significant patient spread. PMID:15531250

  3. Amazing Animals

    Science.gov (United States)

    Al-Kuwari, Najat Saad

    2007-01-01

    "Animals" is a three-part lesson plan for young learners with a zoo animal theme. The first lesson is full of activities to describe animals, with Simon Says, guessing games, and learning stations. The second lesson is about desert animals, but other types of animals could be chosen depending on student interest. This lesson teaches…

  4. The impact of SARS on hospital performance

    Directory of Open Access Journals (Sweden)

    Chen Ran-Chou

    2008-11-01

    Full Text Available Abstract Background During the SARS epidemic, healthcare utilization and medical services decreased significantly. However, the long-term impact of SARS on hospital performance needs to be further discussed. Methods A municipal hospital in Taipei City was shut down for a month due to SARS and then became the designated SARS and infectious disease hospital for the city. This study collected the outpatient, inpatient and emergency service volumes for every year from April to March over four years. Average monthly service amount ± standard deviation were used to compare patient volume for the whole hospital, as well as the outpatient numbers accessing different departments. The ARIMA model of outpatient volume in the pre-SARS year was developed. Results The average monthly service volume of outpatient visits for the base year 2002 was 52317 ± 4204 visits per month, and number for 2003 and the following two years were 55%, 82% and 84% of the base year respectively. The average emergency service volume was 4382 ± 356 visits per month at the base year and this became 45%, 77% and 87% of the base year for the following three years respectively. Average inpatient service volume was 8520 ± 909 inpatient days per month at the base year becoming 43%, 81% and 87% of the base year for the following three years respectively. Only the emergency service volume had recovered to the level of a non-significant difference at the second year after SARS. In addition, the departments of family medicine, metabolism and nephrology reached the 2002 patient number in 2003. The ARIMA (2,1,0 model was the most suitable for outpatient volume in pre-SARS year. The MAPE of the ARIMA (2,1,0 model for the pre-SARS year was 6.9%, and 43.2%, 10.6%, 6.2% for following 3 years. Conclusion This study demonstrates that if a hospital is completely shut down due to SARS or a similar disease, the impact is longer than previous reported and different departments may experience

  5. 9 CFR 107.1 - Veterinary practitioners and animal owners.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Veterinary practitioners and animal owners. 107.1 Section 107.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS...

  6. A modified algorithm for SAR parallel imaging

    Institute of Scientific and Technical Information of China (English)

    HU Ju-rong; WANG Fei; CAO Ning; LU Hao

    2009-01-01

    Synthetic aperture radar can provide two dimension images by converting the acquired echoed SAR signal to targets coordinate and reflectivity. With the advancement of sophisticated SAR signal processing, more and more SAR imaging methods have been proposed for synthetic aperture radar which works at near field and the Fresnel approximation is not appropriate. Time domain correlation is a kind of digital reconstruction method based on processing the synthetic aperture radar data in the two-dimensional frequency domain via Fourier transform. It reconstructs SAR image via simply correlation without any need for approximation or interpolation. But its high computational cost for correlation makes it unsuitable for real time imaging. In order to reduce the computational burden a modified algorithm about time domain correlation was given in this paper. It also can take full advantage of parallel computations of the imaging processor. Its practical implementation was proposed and the preliminary simulation results were presented. Simulation results show that the proposed algorithm is a computationally efficient way of implementing the reconstruction in real time SAR image processing.

  7. Automated rectification and geocoding of SAR imagery

    Science.gov (United States)

    Kwok, R.; Curlander, J. C.

    1987-01-01

    An automated post-processing system has been developed for rectification and geocoding of SAR (Synthetic Aperture Radar) imagery. The system uses as input a raw uncorrected image from the operational SAR correlator, and produces as a standard output a rectified and geocoded product. The accurate geolocation of SAR image pixels is provided by a spatial transformation model which maps the slant range-azimuth SAR image pixels into their location on a prespecified map grid. This model predicts the geodetic location of each pixel by utilizing: the sensor platform position; a geoid model; the parameters of the data collection system and the processing parameters used in the SAR correlator. Based on their geodetic locations, the pixels are mapped by using the desired cartographic projection equations. This rectification and geocoding technique has been tested with Seasat and SIR-B images. The test results demonstrate absolute location uncertainty of less than 50 m and relative distortion (scale factor and skew) of less than 0.1 percent relative to local variations from the assumed geoid.

  8. SARS revisited: managing "outbreaks" with "communications".

    Science.gov (United States)

    Menon, K U

    2006-05-01

    "Risk communications" has acquired some importance in the wake of our experience of SARS. Handled well, it helps to build mutual respect between a government or an organisation and the target groups with which it is communicating. It helps nurture public trust and confidence in getting over the crisis. The World Health Organization (WHO) has also come to recognise its importance after SARS and organised the first Expert Consultation on Outbreak Communications conference in Singapore in September 2004. This article assesses the context and the key features which worked to Singapore's advantage. Looking at the data now widely available on the Internet of the experience of SARS-infected countries like China, Taiwan, Canada, the article identifies the key areas of strategic communications in which Singapore fared particularly well. Another issue discussed is whether Singapore's experience has universal applicability or whether it is limited because of Singapore's unique cultural, historical and geographical circumstances. Finally, the article also looks at some of the post-SARS enhancements that have been put in place following the lessons learnt from SARS and the need to confront new infectious outbreaks like avian flu. PMID:16830005

  9. SAR of psilocybin analogs: discovery of a selective 5-HT 2C agonist.

    Science.gov (United States)

    Sard, Howard; Kumaran, Govindaraj; Morency, Cynthia; Roth, Bryan L; Toth, Beth Ann; He, Ping; Shuster, Louis

    2005-10-15

    An SAR study of psilocybin and psilocin derivatives reveals that 1-methylpsilocin is a selective agonist at the h5-HT(2C) receptor. The corresponding phosphate derivative, 1-methylpsilocybin, shows efficacy in an animal model for obsessive-compulsive disorder, as does 4-fluoro-N,N-dimethyltryptamine. These results suggest a new area for development of novel 5-HT(2C) agonists with applications for drug discovery.

  10. 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 ...

  11. Completing the gaps in Kilauea's Father's Day InSAR displacement signature with ScanSAR

    Science.gov (United States)

    Bertran Ortiz, A.; Pepe, A.; Lanari, R.; Lundgren, P.; Rosen, P. A.

    2009-12-01

    Currently there are gaps in the known displacement signature obtained with InSAR at Kilauea between 2002 and 2009. InSAR data can be richer than GPS because of denser spatial cover. However, to better model rapidly varying and non-steady geophysical events InSAR is limited because of its less dense time observations of the area under study. The ScanSAR mode currently available in several satellites mitigates this effect because the satellite may illuminate a given area more than once within an orbit cycle. The Kilauea displacement graph below from Instituto per Il Rilevamento Electromagnetico dell'Ambiente (IREA) is a cut in space of the displacement signature obtained from a time series of several stripmap-to-stripmap interferograms. It shows that critical information is missing, especially between 2006 and 2007. The displacement is expected to be non-linear judging from the 2007-2008 displacement signature, thus simple interpolation would not suffice. The gap can be filled by incorporating Envisat stripmap-to-ScanSAR interferograms available during that time period. We propose leveraging JPL's new ROI-PAC ScanSAR module to create stripmap-to-ScanSAR interferograms. The new interferograms will be added to the stripmap ones in order to extend the existing stripmap time series generated by using the Small BAseline Subset (SBAS) technique. At AGU we will present denser graphs that better capture Kilauea's displacement between 2003 and 2009.

  12. Simultaneous Observation Data of GB-SAR/PiSAR to Detect Flooding in an Urban Area

    Directory of Open Access Journals (Sweden)

    Manabu Watanabe

    2010-01-01

    Full Text Available We analyzed simultaneous observation data with ground-based synthetic aperture radar (GB-SAR and airborne SAR (PiSAR over a flood test site at which a simple house was constructed in a field. The PiSAR σ∘ under flood condition was 0.9 to 3.4 dB higher than that under nonflood condition. GB-SAR gives high spatial resolution as we could identify a single scattering component and a double bounce component from the house. GB-SAR showed that the σ∘ difference between the flooding and nonflooding conditions came from the double bounce scattering. We also confirm that the entropy is a sensitive parameter in the eigenvalue decomposition parameters, if the scattering process is dominated by the double bounce scattering. We conclude that σ∘ and entropy are a good parameter to be used to detect flooding, not only in agricultural and forest regions, but also in urban areas. We also conclude that GB-SAR is a powerful tool to supplement satellite and airborne observation, which has a relatively low spatial resolution.

  13. Simultaneous Observation Data of GB-SAR/PiSAR to Detect Flooding in an Urban Area

    Directory of Open Access Journals (Sweden)

    Shimada Masanobu

    2010-01-01

    Full Text Available Abstract We analyzed simultaneous observation data with ground-based synthetic aperture radar (GB-SAR and airborne SAR (PiSAR over a flood test site at which a simple house was constructed in a field. The PiSAR under flood condition was 0.9 to 3.4 dB higher than that under nonflood condition. GB-SAR gives high spatial resolution as we could identify a single scattering component and a double bounce component from the house. GB-SAR showed that the difference between the flooding and nonflooding conditions came from the double bounce scattering. We also confirm that the entropy is a sensitive parameter in the eigenvalue decomposition parameters, if the scattering process is dominated by the double bounce scattering. We conclude that and entropy are a good parameter to be used to detect flooding, not only in agricultural and forest regions, but also in urban areas. We also conclude that GB-SAR is a powerful tool to supplement satellite and airborne observation, which has a relatively low spatial resolution.

  14. Characterizing and estimating noise in InSAR and InSAR time series with MODIS

    Science.gov (United States)

    Barnhart, William D.; Lohman, Rowena B.

    2013-01-01

    InSAR time series analysis is increasingly used to image subcentimeter displacement rates of the ground surface. The precision of InSAR observations is often affected by several noise sources, including spatially correlated noise from the turbulent atmosphere. Under ideal scenarios, InSAR time series techniques can substantially mitigate these effects; however, in practice the temporal distribution of InSAR acquisitions over much of the world exhibit seasonal biases, long temporal gaps, and insufficient acquisitions to confidently obtain the precisions desired for tectonic research. Here, we introduce a technique for constraining the magnitude of errors expected from atmospheric phase delays on the ground displacement rates inferred from an InSAR time series using independent observations of precipitable water vapor from MODIS. We implement a Monte Carlo error estimation technique based on multiple (100+) MODIS-based time series that sample date ranges close to the acquisitions times of the available SAR imagery. This stochastic approach allows evaluation of the significance of signals present in the final time series product, in particular their correlation with topography and seasonality. We find that topographically correlated noise in individual interferograms is not spatially stationary, even over short-spatial scales (InSAR time series. We examine the MODIS-based confidence bounds in regions with a range of inferred displacement rates, and find we are capable of resolving velocities as low as 1.5 mm/yr with uncertainties increasing to ∼6 mm/yr in regions with higher topographic relief.

  15. 建立H5N1流感病毒感染雪貂动物模型%Establish H5N1 Flu Virus Infection Ferret Animal Model

    Institute of Scientific and Technical Information of China (English)

    鲍琳琳; 占玲俊; 邓巍; 许黎黎; 朱华; 吕琦; 李枫棣; 秦川

    2011-01-01

    目的 建立甲型H5Nl流感病毒感染雪貂动物模型[1-3].方法 H5Nl流感病毒株A/Vietnam/1203/2004病毒以10(3)和10(4)TCID50滴度分别感染雪貂.对4~10月龄去势雪貂经兽用氯胺酮轻度麻醉后进行滴鼻感染,每个稀释度接种3只雪貂,感染后第5天安乐处死.感染后每天记录雪貂一般临床变化.感染前0d采集鼻甲骨活检,感染后1~5 d鼻甲骨活检检测病毒载量和病毒滴度.处死时取雪貂气管、肺、心、肝、脾、肾、小肠、脑组织作病毒滴度检测和病理检查.结果 H5N110(3)和10(4)TCID50的病毒分别感染雪貂,雪貂死亡都率在33%.10(3)TCID50和10(4)TCID50病毒分别感染雪貂,动物都出现持续3d体温升高,10(4)TCID50组出现超过20%的体重下降.上呼吸道排毒呈现上升趋势,并可在除呼吸系统以外的组织器官中分离到病毒.感染的雪貂病理表现为重度肺炎.结论 雪貂感染H5N1病毒株后在临床表现、病毒学、分子生物学、病理学方面的检测都可以证实雪貂感染H5N1病毒动物模型已建立,10(4)TCID50病毒滴度是一个建立感染动物模型比较合适的剂量.%Objective To establish the Influenza H5N1 influenza virus infection ferrets animal model. Methods Groups of three 4- to 6- month -old ferrets were inoculated intranasally with 103 and 104TCIDM of H5N1 A /Vietnam/1203/ 2004 in a volume of SOOuL. Ferrets were monitored daily for clinical signs of influenza infection, and body temperatures were recorded once daily. Every day take nasal turbinates for RT-PCR. On day 5 postinoculation, ferrets were euthanized and trachea,lung, heart, liver, slpeen, kidney, small intestine, and brain tissue were harvested, and examined by light microscopy. Results For each titer virus tested, in infected ferrets, we observed fever, weight loss, nasal rattling, sneezing and died. Virus was detected in the nasal turbinates and heart, liver, slpeen, kidney, small intestine, and brain from all of the

  16. Substitution at aspartic acid 1128 in the SARS coronavirus spike glycoprotein mediates escape from a S2 domain-targeting neutralizing monoclonal antibody.

    Directory of Open Access Journals (Sweden)

    Oi-Wing Ng

    Full Text Available The Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV is the etiological agent for the infectious disease, SARS, which first emerged 10 years ago. SARS-CoV is a zoonotic virus that has crossed the species barriers to infect humans. Bats, which harbour a diverse pool of SARS-like CoVs (SL-CoVs, are believed to be the natural reservoir. The SARS-CoV surface Spike (S protein is a major antigenic determinant in eliciting neutralizing antibody production during SARS-CoV infection. In our previous work, we showed that a panel of murine monoclonal antibodies (mAbs that target the S2 subunit of the S protein are capable of neutralizing SARS-CoV infection in vitro (Lip KM et al, J Virol. 2006 Jan; 80(2: 941-50. In this study, we report our findings on the characterization of one of these mAbs, known as 1A9, which binds to the S protein at a novel epitope within the S2 subunit at amino acids 1111-1130. MAb 1A9 is a broadly neutralizing mAb that prevents viral entry mediated by the S proteins of human and civet SARS-CoVs as well as bat SL-CoVs. By generating mutant SARS-CoV that escapes the neutralization by mAb 1A9, the residue D1128 in S was found to be crucial for its interaction with mAb 1A9. S protein containing the substitution of D1128 with alanine (D1128A exhibited a significant decrease in binding capability to mAb 1A9 compared to wild-type S protein. By using a pseudotyped viral entry assay, it was shown that the D1128A substitution in the escape virus allows it to overcome the viral entry blockage by mAb 1A9. In addition, the D1128A mutation was found to exert no effects on the S protein cell surface expression and incorporation into virion particles, suggesting that the escape virus retains the same viral entry property as the wild-type virus.

  17. Monitoring of Surface Deformation in Northern Taiwan Using DInSAR and PSInSAR Techniques

    Directory of Open Access Journals (Sweden)

    Chung-Pai Chang

    2010-01-01

    Full Text Available We investigated the surface deformation of the northern Taiwan area, including the Taipei basin and its surrounding mountainous areas of the last fifteen years using the ERS-1, ERS-2 and ENVISAT SAR images. Although the Taipei basin now is well developed and amenable to research gathering using the Differential Interferometric Synthetic Aperture Radar (DInSAR technique, the mountainous areas surrounding the basin are densely covered with various vegetation throughout different seasons inducing high noise ratio in interferograms. Therefore the DInSAR technique is ineffective for observation of surface deformations of these areas. As a result, we developed the Persistent Scatterer (PS InSAR technique to extract the phase signal of the chosen PS points for this study. Our analysis result shows that the atmospheric disturbance and DEM residual can be successfully reduced and the precise information of surface deformation can be effectively obtained by the PSInSAR technique not only in the basin but also in the mountainous areas. Integrating the DInSAR and PSInSAR results, we observed conspicuous deformation events in northern Taiwan including: (1 the slight uplift in the Western Foothills, the Tatun volcanoes, the Linkou Tableland and the Taoyuan area; (2 the subsidence at the border of the Taipei basin; and (3 relative slight uplift rebound in the center of Taipei basin. The displacements along the Shanchiao, Chinshan, and Kanchiao Faults are large enough to be observed; the Taipei, Hsinchuang, and Nankang Faults are too small and cannot be discerned. Further comparison between the DInSAR, PSInSAR, and their corresponding leveling data shows a very coincidental pattern and measurably improves the authenticity of radar interferometry.

  18. Conclusions by the technical officer [The use of non-structural proteins of foot and mouth disease virus (FMDV) to differentiate between vaccinated and infected animals

    International Nuclear Information System (INIS)

    The CRP reflects the variability in approach for various countries with respect to diagnosis and control of FMD and the variability in resources and the different epidemiological niches where tests are used. The papers from the different countries can be examined in this light. Ideally the use of tests should be determined solely from the fitness of purpose criteria. This was reviewed in first paper by the technical officer. Often there is confusion when developing tests and then exploiting them, since the purpose of the test and the validation data to fit that purpose have not been examined properly. This was apparent in the CRP, which was also badly affected since developers' kept changing their reagents and performance criteria. This is a lesson we all have to learn along with a proper understanding of the terms diagnostic sensitivity (DSn) and diagnostic specificity (DSp). Often there is a wish for the most sensitive test without appreciating what the needs for the test are. This is associated closely with the prevalence of the disease or analyte, being studied. In the case of NSP test to determine whether herds are infected, then the prevalence should there be an outbreak is likely to be high (a large percentage of animals might expect to be infected). In this case the diagnostic sensitivity of the test needed can be low. Where there is a need to wheedle out single animals in a large herd, for example if we are looking for positive animals a long time after an outbreak situation, then there is a great need to have both a high diagnostic sensitivity and very high specificity. In between the balance of DSn and DSp come the requirements depending on the likely distribution of FMD. Known history of outbreaks and information on animals cannot be excluded and replaced by testing alone. Full exploitation of the NSP ELISAs and confirmatory tests has not yet been made. One area is the continuous monitoring of animals to see whether there is a low level of FMD

  19. Absolute radiometric calibration of the CCRS SAR

    Science.gov (United States)

    Ulander, Lars M. H.; Hawkins, Robert K.; Livingstone, Charles E.; Lukowski, Tom I.

    1991-11-01

    Determining the radar scattering coefficients from SAR (synthetic aperture radar) image data requires absolute radiometric calibration of the SAR system. The authors describe an internal calibration methodology for the airborne Canada Centre for Remote Sensing (CCRS) SAR system, based on radar theory, a detailed model of the radar system, and measurements of system parameters. The methodology is verified by analyzing external calibration data acquired over a 6-month period in 1988 by the C-band radar using HH polarization. The results indicate that the overall error is +/- 0.8 dB (1-sigma) for incidence angles +/- 20 deg from antenna boresight. The dominant error contributions are due to the antenna radome and uncertainties in the elevation angle relative to the antenna boresight.

  20. Contribution au SAR spatial distribué

    OpenAIRE

    Maréchal, Rozenn

    2006-01-01

    L'obtention d’images à partir de l'émission, de la réception et du traitement d'impulsions radar (SAR) est soumise à différentes contraintes qui limitent les performances telles que la résolution en distance, la résolution en azimut ou la largeur de la Zone imagée (fauchée). Ces limites sont en partie liées à la dimension finie de l’antenne, en particulier dans le cas du SAR spatial. Pour cette raison, on a cherché à étudier la possibilité de mettre au point des systèmes SAR spatiaux distribué...

  1. Accuracy assessment of SAR interferometry using the ERS-1

    OpenAIRE

    Broquetas Ibars, Antoni

    1995-01-01

    A SAR raw data simulator and a SAR processor are used as a tool for performance assessment of SAR interferometry algorithms like the multi-baseline and multifrequency. Traditional algorithms have also been tested with real ERS-1 data and validated with a high accuracy reference DEM. Peer Reviewed

  2. Progress Toward Demonstrating SAR Monitoring of Chinese Seas

    Science.gov (United States)

    Huang, Weigen; Johannessen, Johnny; Alpers, Werner; Yang, Jingsong

    2010-12-01

    "Demonstrating SAR monitoring of Chinese seas" is a project of the ESA-MOST Dragon 2 program. This paper presents the progress of the project. Retrieval algorithms for SAR monitoring of sea surface currents, oceanic internal waves, sea surface winds, oil spills and ships have been advanced. SAR monitoring of Chinese seas in near-real-time is now in demonstration phase.

  3. DESIGN AND ANALYSIS OF MULTI-MODE CLUSTER SAR

    Institute of Scientific and Technical Information of China (English)

    Fan Luhong; Pi Yiming; Hou Yinming

    2004-01-01

    Cluster Synthetic Aperture Radar (SAR) system is composed of a group of spaceborne SAR systems. With its agility of combination, this system can work in several different modes. In this letter, the basic configuration and the working mode of the system are presented.The special performance of the system compared with the conventional SAR system is indicated.

  4. Identification of phosphorylation sites in the nucleocapsid protein (N protein) of SARS-coronavirus

    Science.gov (United States)

    Lin, Liang; Shao, Jianmin; Sun, Maomao; Liu, Jinxiu; Xu, Gongjin; Zhang, Xumin; Xu, Ningzhi; Wang, Rong; Liu, Siqi

    2007-12-01

    After decoding the genome of SARS-coronavirus (SARS-CoV), next challenge is to understand how this virus causes the illness at molecular bases. Of the viral structural proteins, the N protein plays a pivot role in assembly process of viral particles as well as viral replication and transcription. The SARS-CoV N proteins expressed in the eukaryotes, such as yeast and HEK293 cells, appeared in the multiple spots on two-dimensional electrophoresis (2DE), whereas the proteins expressed in E. coli showed a single 2DE spotE These 2DE spots were further examined by Western blot and MALDI-TOF/TOF MS, and identified as the N proteins with differently apparent pI values and similar molecular mass of 50 kDa. In the light of the observations and other evidences, a hypothesis was postulated that the SARS-CoV N protein could be phosphorylated in eukaryotes. To locate the plausible regions of phosphorylation in the N protein, two truncated N proteins were generated in E. coli and treated with PKC[alpha]. The two truncated N proteins after incubation of PKC[alpha] exhibited the differently electrophoretic behaviors on 2DE, suggesting that the region of 1-256 aa in the N protein was the possible target for PKC[alpha] phosphorylation. Moreover, the SARS-CoV N protein expressed in yeast were partially digested with trypsin and carefully analyzed by MALDI-TOF/TOF MS. In contrast to the completely tryptic digestion, these partially digested fragments generated two new peptide mass signals with neutral loss, and MS/MS analysis revealed two phosphorylated peptides located at the "dense serine" island in the N protein with amino acid sequences, GFYAEGSRGGSQASSRSSSR and GNSGNSTPGSSRGNSPARMASGGGK. With the PKC[alpha] phosphorylation treatment and the partially tryptic digestion, the N protein expressed in E. coli released the same peptides as observed in yeast cells. Thus, this investigation provided the preliminary data to determine the phosphorylation sites in the SARS-CoV N protein, and

  5. 9 CFR 113.212 - Bursal Disease Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Bursal Disease Vaccine, Killed Virus..., DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.212 Bursal Disease Vaccine, Killed Virus. Bursal Disease...

  6. 9 CFR 113.213 - Pseudorabies Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Pseudorabies Vaccine, Killed Virus..., DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.213 Pseudorabies Vaccine, Killed Virus. Pseudorabies Vaccine,...

  7. 9 CFR 113.312 - Rabies Vaccine, Live Virus.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Rabies Vaccine, Live Virus. 113.312... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.312 Rabies Vaccine, Live Virus. Rabies Vaccine shall be prepared from...

  8. 9 CFR 113.201 - Canine Distemper Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Canine Distemper Vaccine, Killed Virus..., DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.201 Canine Distemper Vaccine, Killed Virus. Canine Distemper...

  9. 9 CFR 113.204 - Mink Enteritis Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Mink Enteritis Vaccine, Killed Virus..., DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.204 Mink Enteritis Vaccine, Killed Virus. Mink Enteritis...

  10. 9 CFR 113.34 - Detection of hemagglutinating viruses.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of hemagglutinating viruses. 113.34 Section 113.34 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS...

  11. Investigations on the inactivation of selected bacteria and viruses during mesophilic and thermophilic anaerobic alkaline cofermentation of biological waste materials, food residues and other animal residues; Seuchenhygienische Untersuchungen zur Inaktivierung ausgewaehlter Bakterien und Viren bei der mesophilen und thermophilen anaeroben alkalischen Faulung von Bio- und Kuechenabfaellen sowie anderen Rest- und Abfallstoffen tierischer Herkunft

    Energy Technology Data Exchange (ETDEWEB)

    Hoferer, M. [Hohenheim Univ., Stuttgart (Germany). Inst. fuer Umwelt- und Tierhygiene sowie Tiermedizin mit Tierklinik

    2001-07-01

    The purpose of this study is to investigate the inactivation kinetics of a number of different bacteria (Salmonella Senftenberg, Escherichia coli O157, Enterococcus faecium) and viruses (Bovine Enterovirus (ECBO), Equine Rhinovirus (ERV), Poliovirus, Bovine Parvovirus (BPV)) during the process of anaerobic cofermentation. Experiments were conducted in a semi-technical biogas plant at the University of Hohenheim. The fermenter was fed with a mixture of slurry from pigs or cattle (75%) and leftovers (25%) and was run under mesophilic (30 C + 35 C) as well as under thermophilic temperature conditions (50 C + 55 C). Volume and filter-sandwich germ-carriers were specifically developed and/or optimised for these analyses. Parallel to the experiments at the University of Hohenheim and under almost identical process conditions, various viruses (African Swine Fever Virus, Pseudorabies Virus, Classical Swine Fever Virus, Foot and Mouth Disease Virus, Swine Vesicular Disease Virus) were examined at the Federal Research Centre for Virus Diseases of Animals in Tuebingen. The results obtained at each research institution are directly compared. (orig.)

  12. Animal research

    DEFF Research Database (Denmark)

    Olsson, I.A.S.; Sandøe, Peter

    2012-01-01

    in research is analyzed from the viewpoint of three distinct ethical approaches: contractarianism, utilitarianism, and animal rights view. On a contractarian view, research on animals is only an ethical issue to the extent that other humans as parties to the social contract care about how research animals...... are faring. From the utilitarian perspective, the use of sentient animals in research that may harm them is an ethical issue, but harm done to animals can be balanced by benefit generated for humans and other animals. The animal rights view, when thoroughgoing, is abolitionist as regards the use of animals......This article presents the ethical issues in animal research using a combined approach of ethical theory and analysis of scientific findings with bearing on the ethical analysis. The article opens with a general discussion of the moral acceptability of animal use in research. The use of animals...

  13. hPEPT1 Affinity and Translocation of Selected Gln-Sar and Glu-Sar Dipeptide Derivatives

    DEFF Research Database (Denmark)

    Eriksson, A. H.; Elm, Peter L.; Begtrup, Mikael;

    2005-01-01

    . The esters l-Glu(O-i-Bu)-Sar and l-Glu(OCH2Ada)-Sar and the amides l-Gln(N,N-dimethyl)-Sar and l-Gln(N-piperidinyl)-Sar were synthesized, and affinity to and translocation via hPEPT1 were investigated in mature Caco-2 cell monolayers, grown on permeable supports. Affinity was estimated in a competition assay...

  14. Geometric calibration of ERS satellite SAR images

    DEFF Research Database (Denmark)

    Mohr, Johan Jacob; Madsen, Søren Nørvang

    2001-01-01

    Geometric calibration of the European Remote Sensing (ERS) Satellite synthetic aperture radar (SAR) slant range images is important in relation to mapping areas without ground reference points and also in relation to automated processing. The relevant SAR system parameters are discussed...... and calibrated by using the European Space Agency (ESA) transponders at Flevoland. The resulting accuracy of the slant range images corresponds to 10 m horizontally on the ground. The results are verified by using runway intersections and corner reflectors surveyed with differential GPS techniques. Based......, is described to allow other researchers to geometrically calibrate their processing systems...

  15. Fighting SARS in grand collaboration: Our strategies

    Institute of Scientific and Technical Information of China (English)

    钟南山

    2003-01-01

    @@ The war without gunsmoke against severe acute respiratory syndrome(SARS), a type of communicable atypical pneumonia (AP), is now outspreading throughout China and many other countries in the world. So far, the disease has swept through nearly 30 countries and regions. Globally, more than 7,000 people have been infected, with a total of over 550 deaths. More than 5,000 people in mainland of China have been affected and approximately 200 have died. In some areas, the current situation remains at large. It is estimated that SARS has caused a financial loss of over 30 billion dollars (US) worldwide.

  16. Estimating IMU heading error from SAR images.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2009-03-01

    Angular orientation errors of the real antenna for Synthetic Aperture Radar (SAR) will manifest as undesired illumination gradients in SAR images. These gradients can be measured, and the pointing error can be calculated. This can be done for single images, but done more robustly using multi-image methods. Several methods are provided in this report. The pointing error can then be fed back to the navigation Kalman filter to correct for problematic heading (yaw) error drift. This can mitigate the need for uncomfortable and undesired IMU alignment maneuvers such as S-turns.

  17. Science data collection with polarimetric SAR

    DEFF Research Database (Denmark)

    Dall, Jørgen; Woelders, Kim; Madsen, Søren Nørvang

    1996-01-01

    Discusses examples on the use of polarimetric SAR in a number of Earth science studies. The studies are presently being conducted by the Danish Center for Remote Sensing. A few studies of the European Space Agency's EMAC programme are also discussed. The Earth science objectives are presented......, and the potential of polarimetric SAR is discussed and illustrated with data collected by the Danish airborne EMISAR system during a number of experiments in 1994 and 1995. The presentation will include samples of data acquired for the different studies...

  18. Satellite sar detection of hurricane helene (2006)

    DEFF Research Database (Denmark)

    Ju, Lian; Cheng, Yongcun; Xu, Qing;

    2013-01-01

    In this paper, the wind structure of hurricane Helene (2006) over the Atlantic Ocean is investigated from a C-band RADARSAT-1 synthetic aperture radar (SAR) image acquired on 20 September 2006. First, the characteristics, e.g., the center, scale and area of the hurricane eye (HE) are determined. ...... observations from the stepped frequency microwave radiometer (SFMR) on NOAA P3 aircraft. All the results show the capability of hurricane monitoring by satellite SAR. Copyright © 2013 by the International Society of Offshore and Polar Engineers (ISOPE)....

  19. Stochastic dynamic model of SARS spreading

    Institute of Scientific and Technical Information of China (English)

    SHI Yaolin

    2003-01-01

    Based upon the simulation of the stochastic process of infection, onset and spreading of each SARS patient, a system dynamic model of SRAS spreading is constructed. Data from Vietnam is taken as an example for Monte Carlo test. The preliminary results indicate that the time-dependent infection rate is the most important control factor for SARS spreading. The model can be applied to prediction of the course with fluctuations of the epidemics, if the previous history of the epidemics and the future infection rate under control measures are known.

  20. Estimating the Doppler centroid of SAR data

    DEFF Research Database (Denmark)

    Madsen, Søren Nørvang

    1989-01-01

    After reviewing frequency-domain techniques for estimating the Doppler centroid of synthetic-aperture radar (SAR) data, the author describes a time-domain method and highlights its advantages. In particular, a nonlinear time-domain algorithm called the sign-Doppler estimator (SDE) is shown to have...... attractive properties. An evaluation based on an existing SEASAT processor is reported. The time-domain algorithms are shown to be extremely efficient with respect to requirements on calculations and memory, and hence they are well suited to real-time systems where the Doppler estimation is based on raw SAR...

  1. CFAR Edge Detector for Polarimetric SAR Images

    DEFF Research Database (Denmark)

    Schou, Jesper; Skriver, Henning; Nielsen, Allan Aasbjerg;

    2003-01-01

    Finding the edges between different regions in an image is one of the fundamental steps of image analysis, and several edge detectors suitable for the special statistics of synthetic aperture radar (SAR) intensity images have previously been developed. In this paper, a new edge detector for polar......Finding the edges between different regions in an image is one of the fundamental steps of image analysis, and several edge detectors suitable for the special statistics of synthetic aperture radar (SAR) intensity images have previously been developed. In this paper, a new edge detector...

  2. Occurrence of antibodies against insect virus proteins in mammals: simple model to differentiate between passive exposure and active virus growth.

    Science.gov (United States)

    Moore, N F; McKnight, L; Tinsley, T W

    1981-02-01

    Antibodies against an "enterovirus-like" virus of insects, cricket paralysis virus, occur in the sera of domestic animals. When these antibodies were used in combination with the immunoprecipitation of radiolabeled virus proteins from infected Drosophila cells in culture, it could be demonstrated that the animals were exposed to preformed virus. PMID:6260677

  3. Occurrence of antibodies against insect virus proteins in mammals: simple model to differentiate between passive exposure and active virus growth.

    OpenAIRE

    Moore, N F; McKnight, L.; Tinsley, T. W.

    1981-01-01

    Antibodies against an "enterovirus-like" virus of insects, cricket paralysis virus, occur in the sera of domestic animals. When these antibodies were used in combination with the immunoprecipitation of radiolabeled virus proteins from infected Drosophila cells in culture, it could be demonstrated that the animals were exposed to preformed virus.

  4. Pains and Gains from China's Experiences with Emerging Epidemics: From SARS to H7N9.

    Science.gov (United States)

    Wei, Pengfei; Cai, Zelang; Hua, Jinwen; Yu, Weijia; Chen, Jiajie; Kang, Kang; Qiu, Congling; Ye, Lanlan; Hu, Jiayun; Ji, Kunmei

    2016-01-01

    Over the recent decades, China experienced several emerging virus outbreaks including those caused by the severe acute respiratory syndrome- (SARS-) coronavirus (Cov), H5N1 virus, and H7N9 virus. The SARS tragedy revealed faults in China's infectious disease prevention system, propelling the Chinese government to enact reforms that enabled better combating of the subsequent H1N1 and H7N9 avian flu epidemics. The system is buttressed by three fundamental, mutually reinforcing components: (1) enduring government administration reforms, including legislation establishing a unified public health emergency management system; (2) prioritized funding for biotechnology and biomedicine industrialization, especially in the areas of pathogen identification, drug production, and the development of vaccines and diagnostics; and (3) increasing investment for public health and establishment of a rapid-response infectious diseases prevention and control system. China is now using its hard-gained experience to support the fight against Ebola in Africa and the Middle East Respiratory Syndrome in its own country. PMID:27525272

  5. A Real-Time PCR Assay for Bat SARS-Like Coronavirus Detection and Its Application to Italian Greater Horseshoe Bat Faecal Sample Surveys

    Directory of Open Access Journals (Sweden)

    Andrea Balboni

    2012-01-01

    Full Text Available Bats are source of coronaviruses closely related to the severe acute respiratory syndrome (SARS virus. Numerous studies have been carried out to identify new bat viruses related to SARS-coronavirus (bat-SARS-like CoVs using a reverse-transcribed-polymerase chain reaction assay. However, a qualitative PCR could underestimate the prevalence of infection, affecting the epidemiological evaluation of bats in viral ecology. In this work an SYBR Green-real time PCR assay was developed for diagnosing infection with SARS-related coronaviruses from bat guano and was applied as screening tool in a survey carried out on 45 greater horseshoe bats (Rhinolophus ferrumequinum sampled in Italy in 2009. The assay showed high sensitivity and reproducibility. Its application on bats screening resulted in a prevalence of 42%. This method could be suitable as screening tool in epidemiological surveys about the presence of bat-SARS-like CoVs, consequently to obtain a more realistic scenario of the viral prevalence in the population.

  6. Surveillance of animal carriers of Hantan virus and their ectoparasites at Shanghai costal harbors%上海口岸动物宿主携带汉坦病毒及其体表寄生虫监测

    Institute of Scientific and Technical Information of China (English)

    丁鲁民

    2011-01-01

    Objective To monitor rodent carriers of Hantan virus, the pathogen of hemorrhagic fever with renal syndrome (HFRS), and related ectozoan vectors in Shanghai coastal harbors. Methods From 2008 to 2009, quarterly surveys of the rodent carriers were performed in Shanghai coastal harbors of Chongming, Jinshan and Zhapu. The rodents were collected using rat cages and clamps. Blood and lung samples were taken for HFRS viral testingand ectoparasites were collected for laboratory identification. The HFRS-IgG and HFRS-IgM antibodies were detected by ELISA, and MacELISA, respectively. HFRS Hantan virus antigens in lung tissue samples were detected by direct immune florescence technique. Hantan virus genotype was analyzed using RT-PCR. Results A total of 232 rodents and 3 birds were captured, including 4 species of 4 genera of Rodentia and 2 species of 2 genera of Insectivora. None of the samples tested positive for HFRS Hantan virus. Conclusion No Hantan virus positive samples were isolated from the captured rodents in the Shanghai coastal harbors, and only a very small amount of ectoparasites were collected from the animals. Crocidura lasiura was the most common animal in these harbors, and Laelaps jettmari huaihoensis comb.n. Collected from Apodemus agrarius was a new record in Shanghai.%目的 监测上海口岸汉坦病毒在鼠形动物宿主中的携带情况和相关的体外寄生虫种类.方法 2008-2009年每季度对上海市周边的崇明、金山、乍浦等口岸鼠形动物宿主调查1次.通过鼠笼、鼠夹诱捕鼠类,检测其血液和肺组织标本的汉坦病毒.采用ELISA检测血清HFRS-IgG抗体,IgM捕捉ELISA法(MacELISA)检测HFRS-IgM抗体,直接免疫荧光法检测鼠肺组织肾综合征出血热(HFRS)抗原,并通过RT-PCR检测汉坦病毒基因并分型.结果 共捕获鼠形动物232只,其中啮齿目4属4种,食虫目2属2种,还有鸟类3种,体外寄生虫有革螨4属4种,蚤2属2种,吸虱1属1种;用各种检测方法未从

  7. A Review About SAR Technique for Shallow Water Bathymetry Surveys

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Synthetic Aperture Radar (SAR) has become one of the important tools for shallow water bathymetry surveys. This has significant economic efficiency compared with the traditional bathymetry surveys. Numerical models have been developed to simulate shallow water bathymetry SAR images. Inversion of these models makes it possible to assess the water depths from SAR images. In this paper, these numerical models of SAR technique are reviewed, and examples are illustrated including in the coastal areas of China. Some issues about SAR technique available and the research orientation in future are also discussed.

  8. Joint Sparsity in SAR Tomography for Urban Mapping

    OpenAIRE

    Zhu, Xiao Xiang; Ge, Nan; Shahzad, Muhammad

    2015-01-01

    With meter-resolution images delivered by modern SAR satellites like TerraSAR-X and TanDEM-X, it is now possible to map urban areas from space in very high level of detail using advanced interferometric techniques such as PSI and SAR Tomography (TomoSAR), whereas these multi-pass techniques are based on a great number of images. We aim at precise TomoSAR reconstruction while significantly reducing the required number of images by incorporating building a priori knowledge to the estimation. In...

  9. Ambiguity noise analysis of a SAR system

    Science.gov (United States)

    Tian, Haishan; Chang, Wenge; Li, Xiangyang

    2015-12-01

    The presence of range and azimuth (or Doppler) ambiguities in synthetic aperture radars (SARs) is well known. The ambiguity noise is related to the antenna pattern and the value of pulse repetition frequency (PRF). Because a new frequency modulated continuous wave (FMCW) SAR has the characters of low cost and small size, and the capacity of real-time signal processing, the antenna will likely vibrate or deform due to a lack of the stabilized platform. And the value of PRF cannot be much high because of the high computation burden for the real-time processing. The aim of this study is to access and improve the performance of a new FMCW SAR system based on the ambiguity noise. First, the quantitative analysis of the system's ambiguity noise level is performed; an antenna with low sidelobes is designed. The conclusion is that the range ambiguity noise is small; the azimuth ambiguity noise is somewhat increased, however, it is sufficiently small to have marginal influence on the image quality. Finally, the ambiguity noise level is measured using the imaging data from a Ku-band FMCW SAR. The results of this study show that the measured noise level coincides with the theoretical noise level.

  10. Design considerations for large SAR array antennas

    NARCIS (Netherlands)

    Visser, H.J.; Bolt, R.J.

    2000-01-01

    Future space-borne SAR systems should feature wider bandwidth, scanning capability in azimuth and elevation, and above all they should provide full polarisation information because polarimetry is one of the most promising tools for the interpretation of radar signatures. Within the context of these

  11. Epidemic Models for SARS and Measles

    Science.gov (United States)

    Rozema, Edward

    2007-01-01

    Recent events have led to an increased interest in emerging infectious diseases. This article applies various deterministic models to the SARS epidemic of 2003 and a measles outbreak in the Netherlands in 1999-2000. We take a historical approach beginning with the well-known logistic curve and a lesser-known extension popularized by Pearl and Reed…

  12. Multichannel imaging with the AMBER FMCW SAR

    NARCIS (Netherlands)

    Otten, M.P.G.; Rossum, W.L. van; Graaf, M.W. van der; Vlothuizen, W.J.; Tan, R.G.

    2014-01-01

    An X-band Digital Array Synthetic Aperture Radar for a Short Range Tactical UAV is presented. The Frequency Modulated Continuous Wave radar principle in combination with digital beam forming over 24 receive channels is used to achieve low power and advanced imaging SAR capabilities on small platform

  13. Acousto-Optical/Electronic Processor For SAR

    Science.gov (United States)

    Bicknell, T. J.; Farr, W. H.

    1992-01-01

    Lightweight, compact, low-power apparatus processes synthetic-aperture-radar (SAR) returns in real time, providing imagery aboard moving aircraft or spacecraft platform. Processor includes optical and electronic subsystems that, together, resolve range and azimuth coordinates of radar targets by combination of spatial and temporal integrations.

  14. Cross-calibration of interferometric SAR data

    DEFF Research Database (Denmark)

    Dall, Jørgen

    2003-01-01

    Generation of digital elevation models from interferometric synthetic aperture radar (SAR) data is a well established technique. Achieving a high geometric fidelity calls for a calibration accounting for inaccurate navigation data and system parameters as well as system imperfections. Fully autom...

  15. Living in the Shadow of SARS

    Institute of Scientific and Technical Information of China (English)

    LUZHU

    2003-01-01

    I Was born in April, when spring is in the air, the sun shines, the sky is blue, and the fragrance of lilacs is everywhere. This year's birthday was unforgettable.As the SARS epidemic had broken out in Beijing, it was spent under the threat of this killer disease.

  16. Multi-channel SAR for tactical UAV

    NARCIS (Netherlands)

    Otten, M.P.G.; Maas, A.P.M.; Bolt, R.J.; Graaf, M.W. van der; Huizing, A.G.; Medenblik, H.J.W.; Dorp, P. van

    2011-01-01

    A light weight SAR has been designed and built, suitable for use on short range tactical UAVs. The system consists of a fully digital receive array, and a very compact active transmit antenna. The approximate weight of the complete system is 6 kg, with power consumption below 75 W, depending on the

  17. SAR Raw Data Generation for Complex Airport Scenes

    Directory of Open Access Journals (Sweden)

    Jia Li

    2014-10-01

    Full Text Available The method of generating the SAR raw data of complex airport scenes is studied in this paper. A formulation of the SAR raw signal model of airport scenes is given. Via generating the echoes from the background, aircrafts and buildings, respectively, the SAR raw data of the unified SAR imaging geometry is obtained from their vector additions. The multipath scattering and the shadowing between the background and different ground covers of standing airplanes and buildings are analyzed. Based on the scattering characteristics, coupling scattering models and SAR raw data models of different targets are given, respectively. A procedure is given to generate the SAR raw data of airport scenes. The SAR images from the simulated raw data demonstrate the validity of the proposed method.

  18. Citizens’ Health Information Behaviors During SARS Spread Periods in Taiwan

    Directory of Open Access Journals (Sweden)

    Nei-Ching Yeh

    2003-09-01

    Full Text Available The purpose of this study is to investigate the information behaviors of citizens during the periods of SARS spreading in Taiwan. This study is exploratory in nature, and the naturalistic inquiry approach was applied. Sixteen persons, aged from 20 to 62 years old, were interviewed in order to understand their primary information channels of obtaining SARS information, the characteristics of information communication, the methods of infection, the attitudes toward SARS news, and the influences of SARS to life. The findings show that most participants obtained SARS information from televisions. SARS became the major topic of chatting between people, but telephone communication replaced face to face communication. Part of interviewers applied folk medicine to guard against SARS. Participant dissatisfied that governments did not announce much more authoritative information. The results also found participants’ information sharing and information avoidance behaviors.[Article content in Chinese

  19. The first Sentinel-1 SAR image of a typhoon

    Institute of Scientific and Technical Information of China (English)

    LI Xiaofeng

    2015-01-01

    In this note, we present the first Sentinel-1 synthetic aperture radar (SAR) typhoon image acquired in the northwest Pacific on October 4, 2014. The eye shape and sea surface wind patterns associated with Typhoon Phanfone are clearly shown in the high-quality SAR image. SAR winds retrieval procedure was given but the actual wind estimates will only be available after the European Space Agency (ESA) releases the official calibration coefficients in order to accurately derive the SAR-measured normalized radar cross section. This study demonstrates the advantage of Sentinel-1 SAR with regards to imaging fine scale typhoon patterns on the sea surface beneath storm clouds. This paper also advocates the use of Sentinel-1 SAR data that is made freely and openly available worldwide for the first time in civilian SAR history.

  20. 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)

  1. Analysis of Multipath Pixels in SAR Images

    Science.gov (United States)

    Zhao, J. W.; Wu, J. C.; Ding, X. L.; Zhang, L.; Hu, F. M.

    2016-06-01

    As the received radar signal is the sum of signal contributions overlaid in one single pixel regardless of the travel path, the multipath effect should be seriously tackled as the multiple bounce returns are added to direct scatter echoes which leads to ghost scatters. Most of the existing solution towards the multipath is to recover the signal propagation path. To facilitate the signal propagation simulation process, plenty of aspects such as sensor parameters, the geometry of the objects (shape, location, orientation, mutual position between adjacent buildings) and the physical parameters of the surface (roughness, correlation length, permittivity)which determine the strength of radar signal backscattered to the SAR sensor should be given in previous. However, it's not practical to obtain the highly detailed object model in unfamiliar area by field survey as it's a laborious work and time-consuming. In this paper, SAR imaging simulation based on RaySAR is conducted at first aiming at basic understanding of multipath effects and for further comparison. Besides of the pre-imaging simulation, the product of the after-imaging, which refers to radar images is also taken into consideration. Both Cosmo-SkyMed ascending and descending SAR images of Lupu Bridge in Shanghai are used for the experiment. As a result, the reflectivity map and signal distribution map of different bounce level are simulated and validated by 3D real model. The statistic indexes such as the phase stability, mean amplitude, amplitude dispersion, coherence and mean-sigma ratio in case of layover are analyzed with combination of the RaySAR output.

  2. BioSAR Airborne Biomass Sensing System

    Energy Technology Data Exchange (ETDEWEB)

    Graham, R.L.; Johnson, P.

    2007-05-24

    This CRADA was developed to enable ORNL to assist American Electronics, Inc. test a new technology--BioSAR. BioSAR is a an airborne, low frequency (80-120 MHz {approx} FM radio frequencies) synthetic aperture radar (SAR) technology which was designed and built for NASA by ZAI-Amelex under Patrick Johnson's direction. At these frequencies, leaves and small branches are nearly transparent and the majority of the energy reflected from the forest and returned to the radar is from the tree trunks. By measuring the magnitude of the back scatter, the volume of the tree trunk and therefore the biomass of the trunks can be inferred. The instrument was successfully tested on tropical rain forests in Panama. Patrick Johnson, with American Electronics, Inc received a Phase II SBIR grant from DOE Office of Climate Change to further test and refine the instrument. Mr Johnson sought ORNL expertise in measuring forest biomass in order for him to further validate his instrument. ORNL provided ground truth measurements of forest biomass at three locations--the Oak Ridge Reservation, Weyerhaeuser Co. commercial pine plantations in North Carolina, and American Energy and Power (AEP) Co. hardwood forests in southern Ohio, and facilitated flights over these forests. After Mr. Johnson processed the signal data from BioSAR instrument, the processed data were given to ORNL and we attempted to derive empirical relationships between the radar signals and the ground truth forest biomass measurements using standard statistical techniques. We were unsuccessful in deriving such relationships. Shortly before the CRADA ended, Mr Johnson discovered that FM signal from local radio station broadcasts had interfered with the back scatter measurements such that the bulk of the signal received by the BioSAR instrument was not backscatter from the radar but rather was local radio station signals.

  3. The tale of a modern animal plague: Tracing the evolutionary history and determining the time-scale for foot and mouth disease virus

    International Nuclear Information System (INIS)

    Despite significant advances made in the understanding of its epidemiology, foot and mouth disease virus (FMDV) is among the most unexpected agricultural devastating plagues. While the disease manifests itself as seven immunologically distinct strains their origin, population dynamics, migration patterns and divergence times remain unknown. Herein we have assembled a comprehensive data set of gene sequences representing the global diversity of the disease and inferred the time-scale and evolutionary history for FMDV. Serotype-specific rates of evolution and divergence times were estimated using a Bayesian coalescent framework. We report that an ancient precursor FMDV gave rise to two major diversification events spanning a relatively short interval of time. This radiation event is estimated to have taken place towards the end of the 17th and the beginning of the 18th century giving us the present circulating Euro-Asiatic and South African viral strains. Furthermore our results hint that Europe acted as a possible hub for the disease from where it successfully dispersed elsewhere via exploration and trading routes

  4. Expression, purification and crystallization of the SARS-CoV macro domain

    International Nuclear Information System (INIS)

    The SARS-CoV macro domain was expressed, purified and crystallized. Selenomethionine-labelled crystals diffracted to 1.8 Å resolution. Macro domains or X domains are found as modules of multidomain proteins, but can also constitute a protein on their own. Recently, biochemical and structural studies of cellular macro domains have been performed, showing that they are active as ADP-ribose-1′′-phosphatases. Macro domains are also present in a number of positive-stranded RNA viruses, but their precise function in viral replication is still unknown. The major human pathogen severe acute respiratory syndrome coronavirus (SARS-CoV) encodes 16 non-structural proteins (nsps), one of which (nsp3) encompasses a macro domain. The SARS-CoV nsp3 gene region corresponding to amino acids 182–355 has been cloned, expressed in Escherichia coli, purified and crystallized. The crystals belong to space group P21, with unit-cell parameters a = 37.5, b = 55.6, c = 108.9 Å, β = 91.4°, and the asymmetric unit contains either two or three molecules. Both native and selenomethionine-labelled crystals diffract to 1.8 Å

  5. Animal Bites

    Science.gov (United States)

    ... and complications from bites Never pet, handle, or feed unknown animals Leave snakes alone Watch your children closely around animals Vaccinate your cats, ferrets, and dogs against rabies Spay or neuter ...

  6. Animal Bites

    Science.gov (United States)

    Wild animals usually avoid people. They might attack, however, if they feel threatened, are sick, or are protecting their ... or territory. Attacks by pets are more common. Animal bites rarely are life-threatening, but if they ...

  7. Animal Farm

    Institute of Scientific and Technical Information of China (English)

    徐蓉蓉

    2015-01-01

    This essay first introduce the background of Animal Farm and a brief introduction of the author.Then it discuss three thesis about this novel and briefly discussed about it.At last it give highly review on Animal Farm.

  8. Animal Farm

    Institute of Scientific and Technical Information of China (English)

    徐蓉蓉

    2015-01-01

    This essayfirst introduce the background of Animal Farm and a brief introduction of the author.Then it discuss three thesis about this novel and briefly discussed about it.At last it give highly review on Animal Farm.

  9. Animal ethics

    OpenAIRE

    Palmer, Clare; Sandøe, Peter

    2011-01-01

    This chapter describes and discusses different views concerning our duties towards animals. First, we explain why it is necessary to engage in thinking about animal ethics and why it is not enough to rely on feelings alone. Secondly, we present and discuss five different kinds of views about the nature of our duties to animals. They are: contractarianism, utilitarianism, the animal rights view, contextual views, and a respect for nature view. Finally, we briefly consider whether it is possibl...

  10. Enhanced expression of the Erns protein of classical swine fever virus in yeast and its application in an indirect enzyme-linked immunosorbent assay for antibody differentiation of infected from vaccinated animals.

    Science.gov (United States)

    Luo, Yuzi; Li, Lin; Austermann-Busch, Sophia; Dong, Mei; Xu, Jingjing; Shao, Lina; Lei, Jianlin; Li, Na; He, Wen-Rui; Zhao, Bibo; Li, Su; Li, Yongfeng; Liu, Lihong; Becher, Paul; Sun, Yuan; Qiu, Hua-Ji

    2015-09-15

    Classical swine fever (CSF), caused by classical swine fever virus (CSFV), is a devastating disease of swine worldwide. Although a mandatory vaccination with the modified live vaccine C-strain has been implemented in China for decades, CSF remains a serious threat to the swine industry. To facilitate the control and eradication of CSF in China, the E2-based marker vaccine rAdV-SFV-E2, an adenovirus-delivered, alphavirus replicon-vectored vaccine, has been developed. Accordingly, an accompanying discriminatory test that allows differentiating infected from vaccinated animals (DIVA) is required. Here, the enhanced expression of E(rns) protein of CSFV was achieved in the methyltropic yeast Pichia pastoris by codon-optimization of the E(rns) gene, and an indirect enzyme-linked immunosorbent assay (iELISA) based on the yeast-expressed E(rns) (yE(rns)) was developed and evaluated. The optimized iELISA was able to detect CSFV-specific antibodies in the serum samples from the CSFV-infected pigs as early as 6 days post-infection, and discriminate the CSFV-infected pigs from those vaccinated with rAdV-SFV-E2. The iELISA was evaluated using a panel of swine sera, and showed comparable sensitivity (94.6%) and specificity (97.1%), and the consistence rates with the virus neutralization test were 96.8% for CSFV-infected swine sera, 83.3% for C-strain-vaccinated swine sera, and 95.0% for field swine sera. In addition, the iELISA showed higher sensitivity (90.4%) compared with PrioCHECK CSFV E(rns) (59.6%). Taken together, the yE(rns)-based iELISA is specific and sensitive, representing a promising DIVA test for E2-based marker vaccines against CSF. PMID:26005003

  11. The E Protein Is a Multifunctional Membrane Protein of SARS-CoV

    Institute of Scientific and Technical Information of China (English)

    Qingfa Wu; Jia Ji; Jing Xu; Jia Ye; Yongwu Hu; Wenjun Chen; Songgang Li; Jun Wang; Jian Wang; Shengli Bi; Huanming Yang; Yilin Zhang; Hong Lü; Jing Wang; Ximiao He; Yong Liu; Chen Ye; Wei Lin; Jianfei Hu

    2003-01-01

    The E (envelope) protein is the smallest structural protein in all coronaviruses andis the only viral structural protein in which no variation has been detected. Weconducted genome sequencing and phylogenetic analyses of SARS-CoV. Based ongenome sequencing, we predicted the E protein is a transmembrane (TM) pro-tein characterized by a TM region with strong hydrophobicity and α-helix con-formation. We identified a segment (NH2-_L-Cys-A-Y-Cys-Cys-N_-COOH) in thecarboxyl-terminal region of the E protein that appears to form three disulfide bondswith another segment of corresponding cysteines in the carboxyl-terminus of the S(spike) protein. These bonds point to a possible structural association between theE and S proteins. Our phylogenetic analyses of the E protein sequences in all pub-lished coronaviruses place SARS-CoV in an independent group in Coronaviridaeand suggest a non-human animal origin.

  12. Animal Deliberation

    NARCIS (Netherlands)

    Driessen, C.P.G.

    2014-01-01

    While much has been written on environmental politics on the one hand, and animal ethics and welfare on the other, animal politics, as the interface of the two, is underexamined. There are key political implications in the increase of animal protection laws, the rights of nature, and political parti

  13. Animal models

    DEFF Research Database (Denmark)

    Gøtze, Jens Peter; Krentz, Andrew

    2014-01-01

    In this issue of Cardiovascular Endocrinology, we are proud to present a broad and dedicated spectrum of reviews on animal models in cardiovascular disease. The reviews cover most aspects of animal models in science from basic differences and similarities between small animals and the human...

  14. Federated query services provided by the Seamless SAR Archive project

    Science.gov (United States)

    Baker, S.; Bryson, G.; Buechler, B.; Meertens, C. M.; Crosby, C. J.; Fielding, E. J.; Nicoll, J.; Youn, C.; Baru, C.

    2013-12-01

    The NASA Advancing Collaborative Connections for Earth System Science (ACCESS) seamless synthetic aperture radar (SAR) archive (SSARA) project is a 2-year collaboration between UNAVCO, the Alaska Satellite Facility (ASF), the Jet Propulsion Laboratory (JPL), and OpenTopography at the San Diego Supercomputer Center (SDSC) to design and implement a seamless distributed access system for SAR data and derived data products (i.e. interferograms). A major milestone for the first year of the SSARA project was a unified application programming interface (API) for SAR data search and results at ASF and UNAVCO (WInSAR and EarthScope data archives) through the use of simple web services. A federated query service was developed using the unified APIs, providing users a single search interface for both archives (http://www.unavco.org/ws/brokered/ssara/sar/search). A command line client that utilizes this new service is provided as an open source utility for the community on GitHub (https://github.com/bakerunavco/SSARA). Further API development and enhancements added more InSAR specific keywords and quality control parameters (Doppler centroid, faraday rotation, InSAR stack size, and perpendicular baselines). To facilitate InSAR processing, the federated query service incorporated URLs for DEM (from OpenTopography) and tropospheric corrections (from the JPL OSCAR service) in addition to the URLs for SAR data. This federated query service will provide relevant QC metadata for selecting pairs of SAR data for InSAR processing and all the URLs necessary for interferogram generation. Interest from the international community has prompted an effort to incorporate other SAR data archives (the ESA Virtual Archive 4 and the DLR TerraSAR-X_SSC Geohazard Supersites and Natural Laboratories collections) into the federated query service which provide data for researchers outside the US and North America.

  15. Simulation of SAR backscatter for forest vegetation

    Science.gov (United States)

    Prajapati, Richa; Kumar, Shashi; Agrawal, Shefali

    2016-05-01

    Synthetic Aperture Radar (SAR) is one of the most recent imaging technology to study the forest parameters. The invincible characteristics of microwave acquisition in cloudy regions and night imaging makes it a powerful tool to study dense forest regions. A coherent combination of radar polarimetry and interferometry (PolInSAR) enhances the accuracy of retrieved biophysical parameters. This paper attempts to address the issue of estimation of forest structural information caused due to instability of radar platforms through simulation of SAR image. The Terai Central Forest region situated at Haldwani area in Uttarakhand state of India was chosen as the study area. The system characteristics of PolInSAR dataset of Radarsat-2 SAR sensor was used for simulation process. Geometric and system specifications like platform altitude, center frequency, mean incidence angle, azimuth and range resolution were taken from metadata. From the field data it was observed that average tree height and forest stand density were 25 m and 300 stems/ha respectively. The obtained simulated results were compared with the sensor acquired master and slave intensity images. It was analyzed that for co-polarized horizontal component (HH), the mean values of simulated and real master image had a difference of 0.3645 with standard deviation of 0.63. Cross-polarized (HV) channel showed better results with mean difference of 0.06 and standard deviation of 0.1 while co-polarized vertical component (VV) did not show similar values. In case of HV polarization, mean variation between simulated and real slave images was found to be the least. Since cross-polarized channel is more sensitive to vegetation feature therefore better simulated results were obtained for this channel. Further the simulated images were processed using PolInSAR inversion modelling approach using three different techniques DEM differencing, Coherence Amplitude Inversion and Random Volume over Ground Inversion. DEM differencing

  16. Fruit bats as a natural reservoir of zoonotic viruses

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    As a natural reservoir of manifold zoonotic viruses, fruit bats have been involved in at least three emerging zoonoses in recent years. This paper aims to introduce the epidemiological characteristics of these diseases emerged in the Australasian region between 1994 and 1999, transmission pathways of the newly discovered viruses and the relationship between the changed entironment of fruit bats and occurrences of these emerging diseases and provide a clue for the epidemiological investigations of SARS.

  17. Entry, Descent, Landing Animation (Animation)

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Click on the image for Entry, Descent, Landing animation This animation illustrates the path the Stardust return capsule will follow once it enters Earth's atmosphere.

  18. Mutational dynamics of the SARS coronavirus in cell culture and human populations isolated in 2003

    Directory of Open Access Journals (Sweden)

    Ooi Eng

    2004-09-01

    Full Text Available Abstract Background The SARS coronavirus is the etiologic agent for the epidemic of the Severe Acute Respiratory Syndrome. The recent emergence of this new pathogen, the careful tracing of its transmission patterns, and the ability to propagate in culture allows the exploration of the mutational dynamics of the SARS-CoV in human populations. Methods We sequenced complete SARS-CoV genomes taken from primary human tissues (SIN3408, SIN3725V, SIN3765V, cultured isolates (SIN848, SIN846, SIN842, SIN845, SIN847, SIN849, SIN850, SIN852, SIN3408L, and five consecutive Vero cell passages (SIN2774_P1, SIN2774_P2, SIN2774_P3, SIN2774_P4, SIN2774_P5 arising from SIN2774 isolate. These represented individual patient samples, serial in vitro passages in cell culture, and paired human and cell culture isolates. Employing a refined mutation filtering scheme and constant mutation rate model, the mutation rates were estimated and the possible date of emergence was calculated. Phylogenetic analysis was used to uncover molecular relationships between the isolates. Results Close examination of whole genome sequence of 54 SARS-CoV isolates identified before 14th October 2003, including 22 from patients in Singapore, revealed the mutations engendered during human-to-Vero and Vero-to-human transmission as well as in multiple Vero cell passages in order to refine our analysis of human-to-human transmission. Though co-infection by different quasipecies in individual tissue samples is observed, the in vitro mutation rate of the SARS-CoV in Vero cell passage is negligible. The in vivo mutation rate, however, is consistent with estimates of other RNA viruses at approximately 5.7 × 10-6 nucleotide substitutions per site per day (0.17 mutations per genome per day, or two mutations per human passage (adjusted R-square = 0.4014. Using the immediate Hotel M contact isolates as roots, we observed that the SARS epidemic has generated four major genetic groups that are

  19. Establishment for quality control of experimental animal

    International Nuclear Information System (INIS)

    Until now, because we have imported experimental animal from foreign experimental animal corporation, we could have saved money by establishing the quality control of animal in barrier system. In order to improve the quality of animal experiment and efficiency of biomedical study, it is indispensable to control many factors that effect in the experiment. Therefore, it is essential to organize the system of laboratory animal care for enhancing reliability and revivability of experimental results. The purpose of the present investigation was to establish the quality control system of experimental animals that we can provide good quality animals according to the experimental condition of each investigator although the exact quality control system to estimate the infection of bacteria and virus easily remains ill-defined yet. Accordingly, we established the useful quality control system for microbiologic monitoring and environmental monitoring to protect experimental animal from harmful bacteria and virus

  20. Establishment for quality control of experimental animal

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Hwan; Kim, Soo Kwan; Kim, Tae Kyoung

    1999-06-01

    Until now, because we have imported experimental animal from foreign experimental animal corporation, we could have saved money by establishing the quality control of animal in barrier system. In order to improve the quality of animal experiment and efficiency of biomedical study, it is indispensable to control many factors that effect in the experiment. Therefore, it is essential to organize the system of laboratory animal care for enhancing reliability and revivability of experimental results. The purpose of the present investigation was to establish the quality control system of experimental animals that we can provide good quality animals according to the experimental condition of each investigator although the exact quality control system to estimate the infection of bacteria and virus easily remains ill-defined yet. Accordingly, we established the useful quality control system for microbiologic monitoring and environmental monitoring to protect experimental animal from harmful bacteria and virus.

  1. Animal Models for HIV Cure Research

    OpenAIRE

    Benjamin B Policicchio; Pandrea, Ivona; Apetrei, Cristian

    2016-01-01

    The HIV-1/AIDS pandemic continues to spread unabated worldwide, and no vaccine exists within our grasp. Effective antiretroviral therapy (ART) has been developed, but ART cannot clear the virus from the infected patient. A cure for HIV-1 is badly needed to stop both the spread of the virus in human populations and disease progression in infected individuals. A safe and effective cure strategy for human immunodeficiency virus (HIV) infection will require multiple tools, and appropriate animal ...

  2. Study on Protective Clothing against SARS Using PTFE/Poly(ether-ester) Membrane

    Institute of Scientific and Technical Information of China (English)

    HAO Xin-min; ZHANG Jian-chun; GUO Yu-hai

    2004-01-01

    By means of texturing with organic conductive fiber, and then being treated with JAM-Y1 anti-bacteria agent, in the end, treated with the XL-550 waterproof agent, the PET fabric has permanent antistatic, anti-bacteria and waterproof and anti-oil properties. The PET fabric was laminated with PTFE membrane by paste dot coating, and then coated by Poly(ether-ester) solution in a direct process. The filter efficiency of NaCl aerosol, penetration property of poliomyelitis virus in liquid and animalcule in air of PET fabric laminated with PTFE membrane are measured. The properties show that the PET fabric laminated with PTFE membrane can separate SARS virus in air and liquid. The protective mechanism is also discussed in the article.

  3. How SARS Taught Me to Cook

    Institute of Scientific and Technical Information of China (English)

    GUAVALEE

    2003-01-01

    DURING the week-long May Day holiday I usually hold a party, or enjoy the good weather on outings with friends, but thanks to the SARS epidemic in Beijing this year, I stayed at home the entire May Day holiday. It was no problem finding something to do with my ample spare time, as I can surf the Internet for hours on end. My biggest headache was eating.Having dined in cafeterias and restaurants for the previous ten years or so, I had never learned to cook, but as SARS had begun to spread in Beijing in late April, the cafeteria in my work unit and most restaurants were closed for the holiday.

  4. Non-parametric partitioning of SAR images

    Science.gov (United States)

    Delyon, G.; Galland, F.; Réfrégier, Ph.

    2006-09-01

    We describe and analyse a generalization of a parametric segmentation technique adapted to Gamma distributed SAR images to a simple non parametric noise model. The partition is obtained by minimizing the stochastic complexity of a quantized version on Q levels of the SAR image and lead to a criterion without parameters to be tuned by the user. We analyse the reliability of the proposed approach on synthetic images. The quality of the obtained partition will be studied for different possible strategies. In particular, one will discuss the reliability of the proposed optimization procedure. Finally, we will precisely study the performance of the proposed approach in comparison with the statistical parametric technique adapted to Gamma noise. These studies will be led by analyzing the number of misclassified pixels, the standard Hausdorff distance and the number of estimated regions.

  5. Automated preprocessing of spaceborne SAR data

    Science.gov (United States)

    Curlander, J. C.; Wu, C.; Pang, A.

    1982-01-01

    An efficient algorithm has been developed for estimation of the echo phase delay in spaceborne synthetic aperture radar (SAR) data. This algorithm utilizes the spacecraft ephemeris data and the radar echo data to produce estimates of two parameters: (1) the centroid of the Doppler frequency spectrum f(d) and (2) the Doppler frequency rate. Results are presented from tests conducted with Seasat SAR data. The test data indicates that estimation accuracies of 3 Hz for f(d) and 0.3 Hz/sec for the Doppler frequency rate are attainable. The clutterlock and autofocus techniques used for estimation of f(d) and the Doppler frequency rate, respectively are discussed and the algorithm developed for optimal implementation of these techniques is presented.

  6. Animal model of respiratory syncytial virus infection and its characteristics and applications%呼吸道合胞病毒感染的动物模型特点及其应用

    Institute of Scientific and Technical Information of China (English)

    徐月波; 董琳

    2014-01-01

    呼吸道合胞病毒(RSV)是世界范围内婴幼儿下呼吸道感染最常见的病原,RSV 感染也是2岁以下婴幼儿病毒感染性疾病最常见的死因,严重威胁健康,迫切需要发展有效的 RSV 疫苗和抗病毒药物。然而,对人类免疫系统在 RSV 感染发病机制、易感性和疫苗安全等方面缺乏深入的了解,限制了RSV 预防和治疗的研究。各种动物模型的发展可以更好地研究 RSV 相关疾病的发病机制以及各类预防和治疗药物。本文综述现有的 RSV 感染动物模型特点及其应用。%Respiratory syncytial virus (RSV)is the most common pathogen which causes lower respiratory tract infections in infant worldwide.RSV infection is also the main cause of death in viral infectious disease in those under two years old,and poses a serious threat to health.There is an ugent need to develope effective RSV vaccine and antiviral drugs.However,the lack of thorough understanding about the pathogenesis,susceptibility,and vaccine safety in human limits the research in prevention and treatment of RSV infection.With the development of various animal models,people can do more better research in the pathogenesis of RSV-associated diseases and a variety of drugs which are used for prevention and therapy.This review focuses on the characteristics of RSV-infected animal models and its application.

  7. Potentials and Limitations of MEO SAR

    OpenAIRE

    Matar, Jalal; López Dekker, Francisco; Krieger, Gerhard

    2016-01-01

    This paper discusses the various aspects of Synthetic Aperture Radar (SAR) missions in Medium Earth Orbits (MEO). It covers the design of suitable orbits and their corresponding coverage, with emphasis on repeat ones. Furthermore, it analyses the changes in performance as altitude increases, while addressing the potentials and limitations of high orbits. Throughout the paper one interesting orbit, repeating its ground track every 3 days and providing near-global coverage, is studied.

  8. Fast SAR Imaging Algorithm for FLGPR

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A fast SAR imaging algorithm for near- field subsurface forward-looking ground penetrating radar (FLGPR) is presented. By using nonstationary convolution filter, the refocused image spectrum can be reconstructed directly from the backscattered signal spectrum of target area. The experimental results show the proposed method can fast achieve image refocusing. Also it has higher computational efficiency than the phase-shift migration approach and the delay-and-sum (DAS) approach.

  9. Reflectarray Membrane Study for Deployable SAR Antenna

    OpenAIRE

    Di Maria, Alberto; Limbach, Markus; Horn, Ralf; Reigber, Andreas

    2009-01-01

    In this paper a reflectarray design for a membrane spaceborne antenna to be used in a typical SAR mission is presented. An L-Band reflectarray, with a dimension of 10 by 6 meters on Kapton foil substrate, has been designed. To evaluate the tolerance to the membrane deformations, a model for the surface wrinkles and sag is developed and their effects on the antenna performance are analyzed. Finally, a full-wave numerical analysis has been performed and the result are prese...

  10. Digital demodulator for wide bandwidth SAR

    DEFF Research Database (Denmark)

    Jørgensen, Jørn Hjelm

    2000-01-01

    A novel approach to the design of efficient digital quadrature demodulators for wide bandwidth SAR systems is described. Efficiency is obtained by setting the intermediate frequency to 1/4 the ADC sampling frequency. One channel is made filter-free by synchronizing the local oscillator...... with the output decimator. The filter required by the other channel is optimized through global search using the system level performance metrics integrated sidelobe level ratio (ISLR) and peak sidelobe level ratio (PSLR)....

  11. Multiplier-free filters for wideband SAR

    DEFF Research Database (Denmark)

    Dall, Jørgen; Christensen, Erik Lintz

    2001-01-01

    This paper derives a set of parameters to be optimized when designing filters for digital demodulation and range prefiltering in SAR systems. Aiming at an implementation in field programmable gate arrays (FPGAs), an approach for the design of multiplier-free filters is outlined. Design results are...... presented in terms of filter complexity and performance. One filter has been coded in VHDL and preliminary results indicate that the filter can meet a 2 GHz input sample rate....

  12. Adaptive Filter in SAR Interferometry Derived DEM

    Institute of Scientific and Technical Information of China (English)

    XU Caijun; WANG Hua; WANG Jianglin; GE Linlin

    2005-01-01

    In this paper, the performance of median filter, elevation dependent adaptive sigma median filter, and directionally dependent adaptive sigma median filter are tested on both InSAR Tandem DEM and simulated high-level noisy DEM. Through the comparison, the directionally dependent adaptive sigma median filter is proved to be the most effective one not only in the noise removing but also in the boundary preserve.

  13. A 3-D SAR approach to IFSAR processing

    Energy Technology Data Exchange (ETDEWEB)

    DOERRY,ARMIN W.; BICKEL,DOUGLAS L.

    2000-03-01

    Interferometric SAR (IFSAR) can be shown to be a special case of 3-D SAR image formation. In fact, traditional IFSAR processing results in the equivalent of merely a super-resolved, under-sampled, 3-D SAR image. However, when approached as a 3-D SAR problem, a number of IFSAR properties and anomalies are easily explained. For example, IFSAR decorrelation with height is merely ordinary migration in 3-D SAR. Consequently, treating IFSAR as a 3-D SAR problem allows insight and development of proper motion compensation techniques and image formation operations to facilitate optimal height estimation. Furthermore, multiple antenna phase centers and baselines are easily incorporated into this formulation, providing essentially a sparse array in the elevation dimension. This paper shows the Polar Format image formation algorithm extended to 3 dimensions, and then proceeds to apply it to the IFSAR collection geometry. This suggests a more optimal reordering of the traditional IFSAR processing steps.

  14. Tannins and Their Impacts on Animal Nutrition

    Directory of Open Access Journals (Sweden)

    Esin Ünver

    2014-06-01

    Full Text Available Tannins are phenolic metabolites, which naturally produced by plants. They can defend plants against pathogen microorganisms and viruses. According to animal nutrition, tannins have both adverse and beneficial effects depending on animal species, physiological state of the animal, structure and concentration of the tannins. The objective of this study was to review the literature about tannins, their effects and usage of tannins in animal nutrition.

  15. Ezrin interacts with the SARS coronavirus Spike protein and restrains infection at the entry stage.

    Directory of Open Access Journals (Sweden)

    Jean Kaoru Millet

    Full Text Available BACKGROUND: Entry of Severe Acute Respiratory Syndrome coronavirus (SARS-CoV and its envelope fusion with host cell membrane are controlled by a series of complex molecular mechanisms, largely dependent on the viral envelope glycoprotein Spike (S. There are still many unknowns on the implication of cellular factors that regulate the entry process. METHODOLOGY/PRINCIPAL FINDINGS: We performed a yeast two-hybrid screen using as bait the carboxy-terminal endodomain of S, which faces the cytosol during and after opening of the fusion pore at early stages of the virus life cycle. Here we show that the ezrin membrane-actin linker interacts with S endodomain through the F1 lobe of its FERM domain and that both the eight carboxy-terminal amino-acids and a membrane-proximal cysteine cluster of S endodomain are important for this interaction in vitro. Interestingly, we found that ezrin is present at the site of entry of S-pseudotyped lentiviral particles in Vero E6 cells. Targeting ezrin function by small interfering RNA increased S-mediated entry of pseudotyped particles in epithelial cells. Furthermore, deletion of the eight carboxy-terminal amino acids of S enhanced S-pseudotyped particles infection. Expression of the ezrin dominant negative FERM domain enhanced cell susceptibility to infection by SARS-CoV and S-pseudotyped particles and potentiated S-dependent membrane fusion. CONCLUSIONS/SIGNIFICANCE: Ezrin interacts with SARS-CoV S endodomain and limits virus entry and fusion. Our data present a novel mechanism involving a cellular factor in the regulation of S-dependent early events of infection.

  16. SARS epidemical forecast research in mathematical model

    Institute of Scientific and Technical Information of China (English)

    DING Guanghong; LIU Chang; GONG Jianqiu; WANG Ling; CHENG Ke; ZHANG Di

    2004-01-01

    The SIJR model, simplified from the SEIJR model, is adopted to analyze the important parameters of the model of SARS epidemic such as the transmission rate, basic reproductive number. And some important parameters are obtained such as the transmission rate by applying this model to analyzing the situation in Hong Kong, Singapore and Canada at the outbreak of SARS. Then forecast of the transmission of SARS is drawn out here by the adjustment of parameters (such as quarantined rate) in the model. It is obvious that inflexion lies on the crunode of the graph, which indicates the big difference in transmission characteristics between the epidemic under control and not under control. This model can also be used in the comparison of the control effectiveness among different regions. The results from this model match well with the actual data in Hong Kong, Singapore and Canada and as a by-product, the index of the effectiveness of control in the later period can be acquired. It offers some quantitative indexes, which may help the further research in epidemic diseases.

  17. The InSAR Scientific Computing Environment

    Science.gov (United States)

    Rosen, Paul A.; Gurrola, Eric; Sacco, Gian Franco; Zebker, Howard

    2012-01-01

    We have developed a flexible and extensible Interferometric SAR (InSAR) Scientific Computing Environment (ISCE) for geodetic image processing. ISCE was designed from the ground up as a geophysics community tool for generating stacks of interferograms that lend themselves to various forms of time-series analysis, with attention paid to accuracy, extensibility, and modularity. The framework is python-based, with code elements rigorously componentized by separating input/output operations from the processing engines. This allows greater flexibility and extensibility in the data models, and creates algorithmic code that is less susceptible to unnecessary modification when new data types and sensors are available. In addition, the components support provenance and checkpointing to facilitate reprocessing and algorithm exploration. The algorithms, based on legacy processing codes, have been adapted to assume a common reference track approach for all images acquired from nearby orbits, simplifying and systematizing the geometry for time-series analysis. The framework is designed to easily allow user contributions, and is distributed for free use by researchers. ISCE can process data from the ALOS, ERS, EnviSAT, Cosmo-SkyMed, RadarSAT-1, RadarSAT-2, and TerraSAR-X platforms, starting from Level-0 or Level 1 as provided from the data source, and going as far as Level 3 geocoded deformation products. With its flexible design, it can be extended with raw/meta data parsers to enable it to work with radar data from other platforms

  18. Prototype Theory Based Feature Representation for PolSAR Images

    OpenAIRE

    Huang Xiaojing; Yang Xiangli; Huang Pingping; Yang Wen

    2016-01-01

    This study presents a new feature representation approach for Polarimetric Synthetic Aperture Radar (PolSAR) image based on prototype theory. First, multiple prototype sets are generated using prototype theory. Then, regularized logistic regression is used to predict similarities between a test sample and each prototype set. Finally, the PolSAR image feature representation is obtained by ensemble projection. Experimental results of an unsupervised classification of PolSAR images show that our...

  19. SAR antenna design for ambiguity and multipath suppression

    OpenAIRE

    Christensen, Erik Lintz; Dich, Mikael

    1993-01-01

    A high resolution airborne synthetic aperture radar (SAR) has been developed at the Electromagnetics Institute (EMI) for remote sensing applications. The paper considers the radiation of antennas for a SAR system from a systems perspective. The basic specifications of an idealised antenna are obtained from the required swath and the azimuth footprint needed for the SAR processing. The radiation from a real antenna causes unwanted signal returns that lead to intensity variations (multipath) an...

  20. SAR11 bacteria linked to ocean anoxia and nitrogen loss

    DEFF Research Database (Denmark)

    Tsementzi, Despina; Wu, Jieying; Deutsch, Samuel;

    2016-01-01

    Bacteria of the SAR11 clade constitute up to one half of all microbial cells in the oxygen-rich surface ocean. SAR11 bacteria are also abundant in oxygen minimum zones (OMZs), where oxygen falls below detection and anaerobic microbes have vital roles in converting bioavailable nitrogen to N2 gas...... activity. These results link SAR11 to pathways of ocean nitrogen loss, redefining the ecological niche of Earth’s most abundant organismal group....

  1. Forming rotated SAR images by real-time motion compensation.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2012-12-01

    Proper waveform parameter selection allows collecting Synthetic Aperture Radar (SAR) phase history data on a rotated grid in the Fourier Space of the scene being imaged. Subsequent image formation preserves the rotated geometry to allow SAR images to be formed at arbitrary rotation angles without the use of computationally expensive interpolation or resampling operations. This should be useful where control of image orientation is desired such as generating squinted stripmaps and VideoSAR applications, among others.

  2. RFI Suppression in Ultrawideband SAR Using an Adaptive Line Enhancer

    OpenAIRE

    Vu, Viet Thuy; Sjögren, Thomas; Pettersson, Mats; Håkansson, Lars; Gustavsson, Anders; Ulander, Lars

    2010-01-01

    In this letter, we propose an approach to suppress radio-frequency interference (RFI) in ultrawideband (UWB) low-frequency synthetic aperture radar (SAR). According to the proposal, RFI is suppressed by using an adaptive line enhancer controlled by the normalized least mean square algorithm. The approach is tested successfully on real UWB low-frequency SAR data. In order to keep the computational burden down, possible ways to integrate the RFI suppression approach into SAR imaging algorithms ...

  3. Death of a SARS case from secondary aspergillus infection

    Institute of Scientific and Technical Information of China (English)

    王慧君; 丁彦青; 徐军; 李欣; 李学锋; 杨磊; 张文丽; 耿健; 申洪; 蔡俊杰; 康伟; 吴正容; 赵菲; 钟南山

    2004-01-01

    @@ Severe acute respiratory syndrome (SARS) is an acute infectious disease which has been found to spread mainly via respiration. The first case was idnetified in Guangdong, southem China in November 2002. This disease has resulted in a severe epidemic outbreak in 27 countries and regions. In order to investigate the etiology and clinicopathologic characteristics of SARS, we reported here a patient with SARS who died of aspergillosis after prolonged treatment with corticosteroids.

  4. RESEARCH ON IMAGE TRANSLATION BETWEEN SAR AND OPTICAL IMAGERY

    OpenAIRE

    Fu; Zhang,

    2012-01-01

    Compare to optical sensors, Synthetic Aperture Radar (SAR) sensors can work at all time and under all weather conditions. However, SAR images are less intuitive and more difficult to understand. To complement advantages of optical and SAR sensors, a technique of image translation is put forward. Firstly, the concept named as remote sensing image translation is presented, and a set of technology thinking for multi-source remote sensing image translation is also given. Image understand...

  5. Differentiation of canine distemper virus isolates in fur animals from various vaccine strains by reverse transcription-polymerase chain reaction-restriction fragment length polymorphism according to phylogenetic relations in china

    Directory of Open Access Journals (Sweden)

    Zhao Jianjun

    2011-02-01

    Full Text Available Abstract In order to effectively identify the vaccine and field strains of Canine distemper virus (CDV, a new differential diagnostic test has been developed based on reverse transcription-polymerase chain reaction (RT-PCR and restriction fragment length polymorphism (RFLP. We selected an 829 bp fragment of the nucleoprotein (N gene of CDV. By RFLP analysis using BamHI, field isolates were distinguishable from the vaccine strains. Two fragments were obtained from the vaccine strains by RT-PCR-RFLP analysis while three were observed in the field strains. An 829 nucleotide region of the CDV N gene was analyzed in 19 CDV field strains isolated from minks, raccoon dogs and foxes in China between 2005 and 2007. The results suggest this method is precise, accurate and efficient. It was also determined that three different genotypes exist in CDV field strains in fur animal herds of the north of China, most of which belong to Asian type. Mutated field strains, JSY06-R1, JSY06-R2 and JDH07-F1 also exist in Northern China, but are most closely related to the standard virulent strain A75/17, designated in Arctic and America-2 genetype in the present study, respectively.

  6. Animal Shelter

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Beijing activist Zhang Luping gives up a lucrative business career to provide a home for stray and abandoned pets "I have never been married, but I have I hundreds of children," said Zhang Luping, founder of the Beijing Human and Animal Environment Education Center (the Animal Center). "God sent me to this planet and gave me the mission of taking care of helpless and homeless dogs and cats. I will never let Him down." The Animal Center, one of a few non-

  7. Animal ethics

    DEFF Research Database (Denmark)

    Palmer, Clare; Sandøe, Peter

    2011-01-01

    the nature of our duties to animals. They are: contractarianism, utilitarianism, the animal rights view, contextual views, and a respect for nature view. Finally, we briefly consider whether it is possible to combine elements from the presented views, and how to make up one’s mind.......This chapter describes and discusses different views concerning our duties towards animals. First, we explain why it is necessary to engage in thinking about animal ethics and why it is not enough to rely on feelings alone. Secondly, we present and discuss five different kinds of views about...

  8. Animated Asphalt

    DEFF Research Database (Denmark)

    Paldam, Camilla Skovbjerg

    2015-01-01

    “animation”, defined as “an innate (and learnable) ability of our bodies to discover life in inanimate images” (Belting 2012, 188). In this essay I investigate the animation of pictures in dialogue with Mitchell, both by addressing general questions such as: how is animation of otherwise static pictures...... to be understood? How does animation differ in different media? And in particular by focusing on and questioning the gender positions inherent in Mitchell’s theory. Animation has an erotic component of seduction and desire, and what pictures want, becomes for Mitchell, what women want. There is of course no simple...

  9. Applications of SAR Interferometry in Earth and Environmental Science Research

    Directory of Open Access Journals (Sweden)

    Xiaobing Zhou

    2009-03-01

    Full Text Available This paper provides a review of the progress in regard to the InSAR remote sensing technique and its applications in earth and environmental sciences, especially in the past decade. Basic principles, factors, limits, InSAR sensors, available software packages for the generation of InSAR interferograms were summarized to support future applications. Emphasis was placed on the applications of InSAR in seismology, volcanology, land subsidence/uplift, landslide, glaciology, hydrology, and forestry sciences. It ends with a discussion of future research directions.

  10. Applications of SAR Interferometry in Earth and Environmental Science Research.

    Science.gov (United States)

    Zhou, Xiaobing; Chang, Ni-Bin; Li, Shusun

    2009-01-01

    This paper provides a review of the progress in regard to the InSAR remote sensing technique and its applications in earth and environmental sciences, especially in the past decade. Basic principles, factors, limits, InSAR sensors, available software packages for the generation of InSAR interferograms were summarized to support future applications. Emphasis was placed on the applications of InSAR in seismology, volcanology, land subsidence/uplift, landslide, glaciology, hydrology, and forestry sciences. It ends with a discussion of future research directions. PMID:22573992

  11. Comparing satellite SAR and wind farm wake models

    OpenAIRE

    Hasager, Charlotte Bay; Vincent, P.; Husson, R.; Mouche, Alexis; Badger, Merete; Pena Diaz, Alfredo; Volker, Patrick; Badger, Jake; Di Bella, Alessandro; Palomares, A.; Cantero, E.; Correia, P. M. F.

    2015-01-01

    The aim of the paper is to present offshore wind farm wake observed from satellite Synthetic Aperture Radar (SAR) wind fields from RADARSAT-1/-2 and Envisat and to compare these wakes qualitatively to wind farm wake model results. From some satellite SAR wind maps very long wakes are observed. These extend several tens of kilometres downwind e.g. 70 km. Other SAR wind maps show near-field fine scale details of wake behind rows of turbines. The satellite SAR wind farm wake cases are modelled b...

  12. Geometric registration and rectification of spaceborne SAR imagery

    Science.gov (United States)

    Curlander, J. C.; Pang, S. N.

    1982-01-01

    This paper describes the development of automated location and geometric rectification techniques for digitally processed synthetic aperture radar (SAR) imagery. A software package has been developed that is capable of determining the absolute location of an image pixel to within 60 m using only the spacecraft ephemeris data and the characteristics of the SAR data collection and processing system. Based on this location capability algorithms have been developed that geometrically rectify the imagery, register it to a common coordinate system and mosaic multiple frames to form extended digital SAR maps. These algorithms have been optimized using parallel processing techniques to minimize the operating time. Test results are given using Seasat SAR data.

  13. SAR11 bacteria linked to ocean anoxia and nitrogen loss

    DEFF Research Database (Denmark)

    Tsementzi, Despina; Wu, Jieying; Deutsch, Samuel;

    2016-01-01

    Bacteria of the SAR11 clade constitute up to one half of all microbial cells in the oxygen-rich surface ocean. SAR11 bacteria are also abundant in oxygen minimum zones (OMZs), where oxygen falls below detection and anaerobic microbes have vital roles in converting bioavailable nitrogen to N2 gas....... Anaerobic metabolism has not yet been observed in SAR11, and it remains unknown how these bacteria contribute to OMZ biogeochemical cycling. Here, genomic analysis of single cells from the world’s largest OMZ revealed previously uncharacterized SAR11 lineages with adaptations for life without oxygen...

  14. Research work on SARS has to be strengthened in China

    Institute of Scientific and Technical Information of China (English)

    王辰

    2003-01-01

    @@ In the spring of 2003, the medical community within China experienced grim challenges when they were confronted with an unexpected disease now referred to as severe acute respiratory syndrome (SARS). During the fight of the bloody war against SARS, Chinese healthcare workers risked of their own lives and dealt with numerous clinical treatments. However, they never forgot their mission to invigorate our nation through science and technology. They actively conducted scientific research on SARS and received preliminary achievements in a very short time, these achievements have become useful tools in the prevention and treatment against SARS.

  15. Crop identification of SAR data using digital textural analysis

    Science.gov (United States)

    Nuesch, D. R.

    1983-01-01

    After preprocessing SEASAT SAR data which included slant to ground range transformation, registration to LANDSAT MSS data and appropriate filtering of the raw SAR data to minimize coherent speckle, textural features were developed based upon the spatial gray level dependence method (SGLDM) to compute entropy and inertia as textural measures. It is indicated that the consideration of texture features are very important in SAR data analysis. The SEASAT SAR data are useful for the improvement of field boundary definitions and for an earlier season estimate of corn and soybean area location than is supported by LANDSAT alone.

  16. Risk Factors for SARS-Related Deaths in 2003, Beijing

    Institute of Scientific and Technical Information of China (English)

    MIN LIU; WAN-NIAN LIANG; QI CHEN; XUE-QIN XIE; JIANG WU; XIONG HE; ZE-JUN LIU

    2006-01-01

    Objective To study the potential risk factors for severe acute respiratory syndromes (SARS)-related deaths in Beijing. Methods Epidemiological data were collected among the confirmed SARS patients officially reported by Beijing Centers for Disease Control and Prevention (BCDC), and information was also supplemented by a follow-up case survey. Chi-square test and multivariate stepwise logistic regression analysis were performed. Results Old age (over 60 years) was found to be significantly associated with SARS-related deaths in the univariate analysis. Also, history of contacting SARS patients within 2 weeks prior to the onset of illness, health occupation, and inferior hospital ranking as well as longer interval of clinic consulting (longer than 1 day) were the risk factors for SARS-related deaths. Multivariate stepwise logistic regression analysis found four risk factors for SARS-related deaths. Conclusion Old age (over 60 years) is the major risk factor for SARS-related deaths.Moreover, hospital health workers, the designated hospitals for SARS clinical services and the interval of consulting doctors (less than 1 day) are protective factors for surviving from SARS.

  17. Epipolar geometry comparison of SAR and optical camera

    Science.gov (United States)

    Li, Dong; Zhang, Yunhua

    2016-03-01

    In computer vision, optical camera is often used as the eyes of computer. If we replace camera with synthetic aperture radar (SAR), we will then enter a microwave vision of the world. This paper gives a comparison of SAR imaging and camera imaging from the viewpoint of epipolar geometry. The imaging model and epipolar geometry of the two sensors are analyzed in detail. Their difference is illustrated, and their unification is particularly demonstrated. We hope these may benefit researchers in field of computer vision or SAR image processing to construct a computer SAR vision, which is dedicated to compensate and improve human vision by electromagnetically perceiving and understanding the images.

  18. Genetic analysis of the SARS-coronavirus spike glycoprotein functional domains involved in cell-surface expression and cell-to-cell fusion

    International Nuclear Information System (INIS)

    The SARS-coronavirus (SARS-CoV) is the etiological agent of severe acute respiratory syndrome (SARS). The SARS-CoV spike (S) glycoprotein mediates membrane fusion events during virus entry and virus-induced cell-to-cell fusion. To delineate functional domains of the SARS-CoV S glycoprotein, single point mutations, cluster-to-lysine and cluster-to-alanine mutations, as well as carboxyl-terminal truncations were investigated in transient expression experiments. Mutagenesis of either the coiled-coil domain of the S glycoprotein amino terminal heptad repeat, the predicted fusion peptide, or an adjacent but distinct region, severely compromised S-mediated cell-to-cell fusion, while intracellular transport and cell-surface expression were not adversely affected. Surprisingly, a carboxyl-terminal truncation of 17 amino acids substantially increased S glycoprotein-mediated cell-to-cell fusion suggesting that the terminal 17 amino acids regulated the S fusogenic properties. In contrast, truncation of 26 or 39 amino acids eliminating either one or both of the two endodomain cysteine-rich motifs, respectively, inhibited cell fusion in comparison to the wild-type S. The 17 and 26 amino-acid deletions did not adversely affect S cell-surface expression, while the 39 amino-acid truncation inhibited S cell-surface expression suggesting that the membrane proximal cysteine-rich motif plays an essential role in S cell-surface expression. Mutagenesis of the acidic amino-acid cluster in the carboxyl terminus of the S glycoprotein as well as modification of a predicted phosphorylation site within the acidic cluster revealed that this amino-acid motif may play a functional role in the retention of S at cell surfaces. This genetic analysis reveals that the SARS-CoV S glycoprotein contains extracellular domains that regulate cell fusion as well as distinct endodomains that function in intracellular transport, cell-surface expression, and cell fusion

  19. Influenza and SARS-coronavirus activating proteases TMPRSS2 and HAT are expressed at multiple sites in human respiratory and gastrointestinal tracts.

    Directory of Open Access Journals (Sweden)

    Stephanie Bertram

    Full Text Available The type II transmembrane serine proteases TMPRSS2 and HAT activate influenza viruses and the SARS-coronavirus (TMPRSS2 in cell culture and may play an important role in viral spread and pathogenesis in the infected host. However, it is at present largely unclear to what extent these proteases are expressed in viral target cells in human tissues. Here, we show that both HAT and TMPRSS2 are coexpressed with 2,6-linked sialic acids, the major receptor determinant of human influenza viruses, throughout the human respiratory tract. Similarly, coexpression of ACE2, the SARS-coronavirus receptor, and TMPRSS2 was frequently found in the upper and lower aerodigestive tract, with the exception of the vocal folds, epiglottis and trachea. Finally, activation of influenza virus was conserved between human, avian and porcine TMPRSS2, suggesting that this protease might activate influenza virus in reservoir-, intermediate- and human hosts. In sum, our results show that TMPRSS2 and HAT are expressed by important influenza and SARS-coronavirus target cells and could thus support viral spread in the human host.

  20. InSAR Scientific Computing Environment

    Science.gov (United States)

    Gurrola, E. M.; Rosen, P. A.; Sacco, G.; Zebker, H. A.; Simons, M.; Sandwell, D. T.

    2010-12-01

    The InSAR Scientific Computing Environment (ISCE) is a software development effort in its second year within the NASA Advanced Information Systems and Technology program. The ISCE will provide a new computing environment for geodetic image processing for InSAR sensors that will enable scientists to reduce measurements directly from radar satellites and aircraft to new geophysical products without first requiring them to develop detailed expertise in radar processing methods. The environment can serve as the core of a centralized processing center to bring Level-0 raw radar data up to Level-3 data products, but is adaptable to alternative processing approaches for science users interested in new and different ways to exploit mission data. The NRC Decadal Survey-recommended DESDynI mission will deliver data of unprecedented quantity and quality, making possible global-scale studies in climate research, natural hazards, and Earth's ecosystem. The InSAR Scientific Computing Environment is planned to become a key element in processing DESDynI data into higher level data products and it is expected to enable a new class of analyses that take greater advantage of the long time and large spatial scales of these new data, than current approaches. At the core of ISCE is both legacy processing software from the JPL/Caltech ROI_PAC repeat-pass interferometry package as well as a new InSAR processing package containing more efficient and more accurate processing algorithms being developed at Stanford for this project that is based on experience gained in developing processors for missions such as SRTM and UAVSAR. Around the core InSAR processing programs we are building object-oriented wrappers to enable their incorporation into a more modern, flexible, extensible software package that is informed by modern programming methods, including rigorous componentization of processing codes, abstraction and generalization of data models, and a robust, intuitive user interface with

  1. Kinetics of Severe Acute Respiratory Syndrome (SARS) Coronavirus-Specific Antibodies in 271 Laboratory-Confirmed Cases of SARS

    OpenAIRE

    He, Zhongping; Dong, Qingming; Zhuang, Hui; Song, Shujing; Peng, Guoai; Luo, Guangxiang; Dwyer, Dominic E.

    2004-01-01

    The sensitivities and specificities of an immunofluorescence assay and an enzyme immunoassay for detection of antibodies specific for severe acute respiratory syndrome coronavirus (SARS-CoV) were compared for 148 laboratory-confirmed SARS cases. The appearance and persistence of SARS-CoV-specific antibodies were assessed, with immunoglobulin G detected in 59% of samples collected within 14 days and persisting for 60 to 95 days after the onset of illness.

  2. Animal Detectives

    Science.gov (United States)

    Mulvey, Bridget; Warnock, Carly

    2015-01-01

    During a two-week inquiry-based 5E learning cycle unit, children made observations and inferences to guide their explorations of animal traits and habitats (Bybee 2014). The children became "animal detectives" by studying a live-feed webcam and digital images of wolves in their natural habitat, reading books and online sources about…

  3. Kindergarten Animation

    Science.gov (United States)

    Hinshaw, Craig

    2012-01-01

    Animation is one of the last lessons that come to mind when thinking of kindergarten art. The necessary understanding of sequencing, attention to small, often detailed drawings, and the use of technology all seem more suitable to upper elementary. With today's emphasis on condensing and integrating curriculum, consider developing animation lessons…

  4. Animal cytomegaloviruses.

    OpenAIRE

    Staczek, J.

    1990-01-01

    Cytomegaloviruses are agents that infect a variety of animals. Human cytomegalovirus is associated with infections that may be inapparent or may result in severe body malformation. More recently, human cytomegalovirus infections have been recognized as causing severe complications in immunosuppressed individuals. In other animals, cytomegaloviruses are often associated with infections having relatively mild sequelae. Many of these sequelae parallel symptoms associated with human cytomegalovir...

  5. ANIMAL code

    International Nuclear Information System (INIS)

    This report describes ANIMAL, a two-dimensional Eulerian magnetohydrodynamic computer code. ANIMAL's physical model also appears. Formulated are temporal and spatial finite-difference equations in a manner that facilitates implementation of the algorithm. Outlined are the functions of the algorithm's FORTRAN subroutines and variables

  6. Classification and monitoring of reed belts using dual-polarimetric TerraSAR-X time series

    Science.gov (United States)

    Heine, Iris; Jagdhuber, Thomas; Itzerott, Sibylle

    2016-04-01

    The shorelines of lakes in northeastern Germany are often covered by reed. These reed belts fulfill an important function as erosion protection, biotope for animals, carbon storage, and as cleaning filter for lake water. However, despite their importance for the limnic ecosystem, reed vegetation in northeastern Germany is not regularly monitored. In this research study we investigate the potential of synthetic aperture radar polarimetry (PolSAR) for seasonal monitoring of reed vegetation. SAR imagery enables sunlight- and (almost) weather-independent monitoring. Polarimetric decomposition techniques allow the physical characterization of the scattering scenario and the involved scatterers. Our study is based on 19 dual-polarimetric (HH/VV) TerraSAR-X images acquired between August 2014 and May 2015. We calculated different polarimetric indices comprising the HH and VV intensities, the dual-polarimetric coherency matrix with dominant and mean alpha scattering angles, entropy and anisotropy (normalized eigen-value difference) as well as combinations of entropy and anisotropy for the analysis of the scattering scenarios. The reed areas in the TerraSAR-X images were classified using a random forest algorithm and validated with high-resolution digital orthophotos. The time series analysis of the reed belts revealed significant seasonal changes in the double bounce sensitive parameters (intensity ratio HH/VV and intensity difference HH-VV, the co-polarimetric coherence phase and the dominant and mean alpha scattering angles). Additionally, the dual-polarimetric coherence (amplitude), anisotropy, entropy, and anisotropy-entropy-combinations showed seasonal changes of reed. In summer, the reed areas are characterized within the X-band SAR data by volume scattering, whereas in winter double-bounce scattering dominates. The volume scattering in summer is caused predominantly by reed leaves. In autumn, the leaves start to wither and fall off, so that in winter predominately

  7. The R Protein of SARS-CoV: Analyses of Structure and Function Based on Four Complete Genome Sequences of Isolates BJ01-BJ04

    Institute of Scientific and Technical Information of China (English)

    Zuyuan Xu; Zizhang Zhang; Jing Xu; Wei Wei; Jingui Zhu; Haiyan Sun; Xiaowei Zhang; Jun Zhou; Songgang Li; Jun Wang; Jian Wang; Haiqing Zhang; Shengli Bi; Huanming Yang; Xiangjun Tian; Jia Ji; Wei Li; Yan Li; Wei Tian; Yujun Han; Lili Wang

    2003-01-01

    The R (replicase) protein is the uniquely defined non-structural protein (NSP)responsible for RNA replication, mutation rate or fidelity, regulation of transcrip-tion in coronaviruses and many other ssRNA viruses. Based on our completegenome sequences of four isolates (BJ01-BJ04) of SARS-CoV from Beijing, China,we analyzed the structure and predicted functions of the R protein in comparisonwith 13 other isolates of SARS-CoV and 6 other coronaviruses. The entire ORF(open-reading frame) encodes for two major enzyme activities, RNA-dependentRNA polymerase (RdRp) and proteinase activities. The R polyprotein under-goes a complex proteolytic process to produce 15 function-related peptides. Ahydrophobic domain (HOD) and a hydrophilic domain (HID) are newly identifiedwithin NSP1. The substitution rate of the R protein is close to the average ofthe SARS-CoV genome. The functional domains in all NSPs of the R proteingive different phylogenetic results that suggest their different mutation rate underselective pressure. Eleven highly conserved regions in RdRp and twelve cleavagesites by 3CLP (chymotrypsin-like protein) have been identified as potential drugtargets. Findings suggest that it is possible to obtain information about the phy-logeny of SARS-CoV, as well as potential tools for drug design, genotyping anddiagnostics of SARS.

  8. Multi-Temporal SAR Interferometry for Landslide Monitoring

    Science.gov (United States)

    Dwivedi, R.; Narayan, A. B.; Tiwari, A.; Dikshit, O.; Singh, A. K.

    2016-06-01

    In the past few years, SAR Interferometry specially InSAR and D-InSAR were extensively used for deformation monitoring related applications. Due to temporal and spatial decorrelation in dense vegetated areas, effectiveness of InSAR and D-InSAR observations were always under scrutiny. Multi-temporal InSAR methods are developed in recent times to retrieve the deformation signal from pixels with different scattering characteristics. Presently, two classes of multi-temporal InSAR algorithms are available- Persistent Scatterer (PS) and Small Baseline (SB) methods. This paper discusses the Stanford Method for Persistent Scatterer (StaMPS) based PS-InSAR and the Small Baselines Subset (SBAS) techniques to estimate the surface deformation in Tehri dam reservoir region in Uttarkhand, India. Both PS-InSAR and SBAS approaches used sixteen ENVISAT ASAR C-Band images for generating single master and multiple master interferograms stack respectively and their StaMPS processing resulted in time series 1D-Line of Sight (LOS) mean velocity maps which are indicative of deformation in terms of movement towards and away from the satellites. From 1D LOS velocity maps, localization of landslide is evident along the reservoir rim area which was also investigated in the previous studies. Both PS-InSAR and SBAS effectively extract measurement pixels in the study region, and the general results provided by both approaches show a similar deformation pattern along the Tehri reservoir region. Further, we conclude that StaMPS based PS-InSAR method performs better in terms of extracting more number of measurement pixels and in the estimation of mean Line of Sight (LOS) velocity as compared to SBAS method. It is also proposed to take up a few major landslides area in Uttarakhand for slope stability assessment.

  9. Impact of the Regulators SigB, Rot, SarA and sarS on the Toxic Shock Tst Promoter and TSST-1 Expression in Staphylococcus aureus.

    Science.gov (United States)

    Andrey, Diego O; Jousselin, Ambre; Villanueva, Maite; Renzoni, Adriana; Monod, Antoinette; Barras, Christine; Rodriguez, Natalia; Kelley, William L

    2015-01-01

    Staphylococcus aureus is an important pathogen manifesting virulence through diverse disease forms, ranging from acute skin infections to life-threatening bacteremia or systemic toxic shock syndromes. In the latter case, the prototypical superantigen is TSST-1 (Toxic Shock Syndrome Toxin 1), encoded by tst(H), and carried on a mobile genetic element that is not present in all S. aureus strains. Transcriptional regulation of tst is only partially understood. In this study, we dissected the role of sarA, sarS (sarH1), RNAIII, rot, and the alternative stress sigma factor sigB (σB). By examining tst promoter regulation predominantly in the context of its native sequence within the SaPI1 pathogenicity island of strain RN4282, we discovered that σB emerged as a particularly important tst regulator. We did not detect a consensus σB site within the tst promoter, and thus the effect of σB is likely indirect. We found that σB strongly repressed the expression of the toxin via at least two distinct regulatory pathways dependent upon sarA and agr. Furthermore rot, a member of SarA family, was shown to repress tst expression when overexpressed, although its deletion had no consistent measurable effect. We could not find any detectable effect of sarS, either by deletion or overexpression, suggesting that this regulator plays a minimal role in TSST-1 expression except when combined with disruption of sarA. Collectively, our results extend our understanding of complex multifactorial regulation of tst, revealing several layers of negative regulation. In addition to environmental stimuli thought to impact TSST-1 production, these findings support a model whereby sporadic mutation in a few key negative regulators can profoundly affect and enhance TSST-1 expression. PMID:26275216

  10. Impact of the Regulators SigB, Rot, SarA and sarS on the Toxic Shock Tst Promoter and TSST-1 Expression in Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Diego O Andrey

    Full Text Available Staphylococcus aureus is an important pathogen manifesting virulence through diverse disease forms, ranging from acute skin infections to life-threatening bacteremia or systemic toxic shock syndromes. In the latter case, the prototypical superantigen is TSST-1 (Toxic Shock Syndrome Toxin 1, encoded by tst(H, and carried on a mobile genetic element that is not present in all S. aureus strains. Transcriptional regulation of tst is only partially understood. In this study, we dissected the role of sarA, sarS (sarH1, RNAIII, rot, and the alternative stress sigma factor sigB (σB. By examining tst promoter regulation predominantly in the context of its native sequence within the SaPI1 pathogenicity island of strain RN4282, we discovered that σB emerged as a particularly important tst regulator. We did not detect a consensus σB site within the tst promoter, and thus the effect of σB is likely indirect. We found that σB strongly repressed the expression of the toxin via at least two distinct regulatory pathways dependent upon sarA and agr. Furthermore rot, a member of SarA family, was shown to repress tst expression when overexpressed, although its deletion had no consistent measurable effect. We could not find any detectable effect of sarS, either by deletion or overexpression, suggesting that this regulator plays a minimal role in TSST-1 expression except when combined with disruption of sarA. Collectively, our results extend our understanding of complex multifactorial regulation of tst, revealing several layers of negative regulation. In addition to environmental stimuli thought to impact TSST-1 production, these findings support a model whereby sporadic mutation in a few key negative regulators can profoundly affect and enhance TSST-1 expression.

  11. Impact of the Regulators SigB, Rot, SarA and sarS on the Toxic Shock Tst Promoter and TSST-1 Expression in Staphylococcus aureus.

    Science.gov (United States)

    Andrey, Diego O; Jousselin, Ambre; Villanueva, Maite; Renzoni, Adriana; Monod, Antoinette; Barras, Christine; Rodriguez, Natalia; Kelley, William L

    2015-01-01

    Staphylococcus aureus is an important pathogen manifesting virulence through diverse disease forms, ranging from acute skin infections to life-threatening bacteremia or systemic toxic shock syndromes. In the latter case, the prototypical superantigen is TSST-1 (Toxic Shock Syndrome Toxin 1), encoded by tst(H), and carried on a mobile genetic element that is not present in all S. aureus strains. Transcriptional regulation of tst is only partially understood. In this study, we dissected the role of sarA, sarS (sarH1), RNAIII, rot, and the alternative stress sigma factor sigB (σB). By examining tst promoter regulation predominantly in the context of its native sequence within the SaPI1 pathogenicity island of strain RN4282, we discovered that σB emerged as a particularly important tst regulator. We did not detect a consensus σB site within the tst promoter, and thus the effect of σB is likely indirect. We found that σB strongly repressed the expression of the toxin via at least two distinct regulatory pathways dependent upon sarA and agr. Furthermore rot, a member of SarA family, was shown to repress tst expression when overexpressed, although its deletion had no consistent measurable effect. We could not find any detectable effect of sarS, either by deletion or overexpression, suggesting that this regulator plays a minimal role in TSST-1 expression except when combined with disruption of sarA. Collectively, our results extend our understanding of complex multifactorial regulation of tst, revealing several layers of negative regulation. In addition to environmental stimuli thought to impact TSST-1 production, these findings support a model whereby sporadic mutation in a few key negative regulators can profoundly affect and enhance TSST-1 expression.

  12. Emerging Viruses in the Felidae: Shifting Paradigms

    Directory of Open Access Journals (Sweden)

    Meredith A. Brown

    2012-02-01

    Full Text Available The domestic cat is afflicted with multiple viruses that serve as powerful models for human disease including cancers, SARS and HIV/AIDS. Cat viruses that cause these diseases have been studied for decades revealing detailed insight concerning transmission, virulence, origins and pathogenesis. Here we review recent genetic advances that have questioned traditional wisdom regarding the origins of virulent Feline infectious peritonitis (FIP diseases, the pathogenic potential of Feline Immunodeficiency Virus (FIV in wild non-domestic Felidae species, and the restriction of Feline Leukemia Virus (FeLV mediated immune impairment to domestic cats rather than other Felidae species. The most recent interpretations indicate important new evolutionary conclusions implicating these deadly infectious agents in domestic and non-domestic felids.

  13. 9 CFR 113.214 - Parvovirus Vaccine, Killed Virus (Canine).

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Parvovirus Vaccine, Killed Virus... REQUIREMENTS Killed Virus Vaccines § 113.214 Parvovirus Vaccine, Killed Virus (Canine). Parvovirus Vaccine... established as follows: (1) Twenty-five parvovirus susceptible dogs (20 vaccinates and 5 controls) shall...

  14. Animal learning.

    Science.gov (United States)

    Castro, Leyre; Wasserman, Edward A

    2010-01-01

    Pavlov and Thorndike pioneered the experimental study of animal learning and provided psychologists with powerful tools to unveil its underlying mechanisms. Today's research developments and theoretical analyses owe much to the pioneering work of these early investigators. Nevertheless, in the evolution of our knowledge about animal learning, some initial conceptions have been challenged and revised. We first review the original experimental procedures and findings of Pavlov and Thorndike. Next, we discuss critical research and consequent controversies which have greatly shaped animal learning theory. For example, although contiguity seemed to be the only condition that is necessary for learning, we now know that it is not sufficient; the conditioned stimulus (CS) also has to provide information about the occurrence of the unconditioned stimulus (US). Also, animals appear to learn different things about the same stimuli when circumstances vary. For instance, when faced with situations in which the meaning of a CS changes, as in the case of acquisition and later extinction, animals seem to preserve the original knowledge (CS-US) in addition to learning about the new conditions (CS-noUS). Finally, we discuss how parallels among Pavlovian conditioning, operant conditioning, and human causal judgment suggest that causal knowledge may lie at the root of both human and animal learning. All of these empirical findings and theoretical developments prove that animal learning is more complex and intricate than was once imagined. Copyright © 2009 John Wiley & Sons, Ltd. For further resources related to this article, please visit the WIREs website. PMID:26272842

  15. Efficient and Quick Inactivation of SARS Coronavirus and Other Microbes Exposed to the Surfaces of Some Metal Catalysts

    Institute of Scientific and Technical Information of China (English)

    JUN HAN; LAN CHEN; SHU-MIN DUAN; QING-XIANG YANG; MIN YANG; CHEN GAO; BAO-YUN ZHANG; HONG HE; XIAO-PING DONG

    2005-01-01

    Objective To study the two metal catalysts Ag/Al2O3 and Cu/Al2O3 that interdict the transmission pathway for SARS and other respiratory infectious diseases. Methods Two metal catalysts Ag/Al2O3 and Cu/Al2O3 were pressed into wafers. One hundred μL 106 TCID50/mL SARS-CoV, 100 μL 106 PFU/mL recombinant baculovirus expressing hamster's prion protein (haPrP) protein and roughly 106 E. coli were slowly dropped onto the surfaces of the catalyst wafers and exposed for 5 and 20 min, respectively. After eluted from the surfaces of wafers, the infectivity of viruses and propagation of bacteria were measured. The expression of PrP protein was determined by Western blot. The morphological changes of bacteria were observed by electronic microscopy. Results After exposure to the catalysts surfaces for 5 and 20 min, the infectivity of SARS-CoV in Vero cells and baculovirus in Sf9 cells dropped down to a very low and undetectable level, and no colony was detected using bacteria culture method. The expression of haPrP protein reduced to 21.8% in the preparation of Sf9 cells infected with recombinant baculovirus exposed for 5 min and was undetectable exposed for 20 min. Bacterial membranes seemed to be cracked and the cytoplasm seemed to be effluent from cell bodies. Conclusion Exposures to the surfaces of Ag/Al2O3 and Cu/Al2O3 destroy the replication and propagation abilities of SARS-CoV, baculovirus and E. coli. Inactivation ability of metal catalysts needs to interact with air, utilizing oxygen molecules in air. Efficiently killing viruses and bacteria on the surfaces of the two metal catalysts has a promising potential for air-disinfection in hospitals, communities, and households.

  16. Wild Animals

    Institute of Scientific and Technical Information of China (English)

    宁静

    2005-01-01

    Many of us think that all wild animals are dangerous. In fact, very few of them will eat a man if he leaves them alone. If you meet a tiger, I'm sure you will run away, but even a tiger doesn't like meeting a man if it isn't hungry. Tigers only kill and eat man when they are too old to catch their food, such as sheep and other small animals. Some animals get frightened when they only smell a man. Some of themst and and look at a man for a short time before they run away.

  17. 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 ...

  18. Genomes of Abundant and Widespread Viruses from the Deep Ocean

    Science.gov (United States)

    Mizuno, Carolina Megumi; Ghai, Rohit; Saghaï, Aurélien; López-García, Purificación

    2016-01-01

    ABSTRACT The deep sea is a massive, largely oligotrophic ecosystem, stretched over nearly 65% of the planet’s surface. Deep-sea planktonic communities are almost completely dependent upon organic carbon sinking from the productive surface, forming a vital component of global biogeochemical cycles. However, despite their importance, viruses from the deep ocean remain largely unknown. Here, we describe the first complete genomes of deep-sea viruses assembled from metagenomic fosmid libraries. “Candidatus Pelagibacter” (SAR11) phage HTVC010P and Puniceispirillum phage HMO-2011 are considered the most abundant cultured marine viruses known to date. Remarkably, some of the viruses described here recruited as many reads from deep waters as these viruses do in the photic zone, and, considering the gigantic scale of the bathypelagic habitat, these genomes provide information about what could be some of the most abundant viruses in the world at large. Their role in the viral shunt in the global ocean could be very significant. Despite the challenges encountered in inferring the identity of their hosts, we identified one virus predicted to infect members of the globally distributed SAR11 cluster. We also identified a number of putative proviruses from diverse taxa, including deltaproteobacteria, bacteroidetes, SAR11, and gammaproteobacteria. Moreover, our findings also indicate that lysogeny is the preferred mode of existence for deep-sea viruses inhabiting an energy-limited environment, in sharp contrast to the predominantly lytic lifestyle of their photic-zone counterparts. Some of the viruses show a widespread distribution, supporting the tenet “everything is everywhere” for the deep-ocean virome. PMID:27460793

  19. Moving Ship SAR Imaging Based on Parameter Estimation

    OpenAIRE

    Yun Yajiao; Qi Xiangyang; Li Ning

    2016-01-01

    The Doppler parameters of moving targets affect the conventional Synthetic Aperture Radar (SAR) imaging. In this study, the relation between the motion and Doppler parameters is established. With improved popular technology, a set of moving ship SAR imaging processes is proposed to obtain a focused and rightlocated image. Simulations and experimental data are used to verify the method.

  20. First demonstration of an X-band airborne FMCW SAR

    NARCIS (Netherlands)

    Meta, A.; Hakkaart, P.; Zwan, F. van der; Hoogeboom, P.; Ligthart, L.P.

    2006-01-01

    At the Delft University of Technology, an X-band airborne FMCW SAR demonstrator system has been designed anddeveloped. The combination of Frequency Modulated Continuous Wave (FMCW) technology and Synthetic Aperture Technique (SAR) has led to a compact, low power consuming imaging system with high re