Petri Net Modeling of Computer Virus Life Cycle | Ikekonwu ...

African Journals Online (AJOL)

Virus life cycle, which refers to the stages of development of a computer virus, is presented as a suitable area for the application of Petri nets. Petri nets a powerful modeling tool in the field of dynamic system analysis is applied to model the virus life cycle. Simulation of the derived model is also presented. The intention of ...

Stability and Hopf bifurcation for a delayed SLBRS computer virus model.

Science.gov (United States)

Zhang, Zizhen; Yang, Huizhong

2014-01-01

By incorporating the time delay due to the period that computers use antivirus software to clean the virus into the SLBRS model a delayed SLBRS computer virus model is proposed in this paper. The dynamical behaviors which include local stability and Hopf bifurcation are investigated by regarding the delay as bifurcating parameter. Specially, direction and stability of the Hopf bifurcation are derived by applying the normal form method and center manifold theory. Finally, an illustrative example is also presented to testify our analytical results.

Stability and Hopf Bifurcation for a Delayed SLBRS Computer Virus Model

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Zizhen Zhang

2014-01-01

Full Text Available By incorporating the time delay due to the period that computers use antivirus software to clean the virus into the SLBRS model a delayed SLBRS computer virus model is proposed in this paper. The dynamical behaviors which include local stability and Hopf bifurcation are investigated by regarding the delay as bifurcating parameter. Specially, direction and stability of the Hopf bifurcation are derived by applying the normal form method and center manifold theory. Finally, an illustrative example is also presented to testify our analytical results.

Ebola virus: A gap in drug design and discovery - experimental and computational perspective.

Science.gov (United States)

Balmith, Marissa; Faya, Mbuso; Soliman, Mahmoud E S

2017-03-01

The Ebola virus, formally known as the Ebola hemorrhagic fever, is an acute viral syndrome causing sporadic outbreaks that have ravaged West Africa. Due to its extreme virulence and highly transmissible nature, Ebola has been classified as a category A bioweapon organism. Only recently have vaccine or drug regimens for the Ebola virus been developed, including Zmapp and peptides. In addition, existing drugs which have been repurposed toward anti-Ebola virus activity have been re-examined and are seen to be promising candidates toward combating Ebola. Drug development involving computational tools has been widely employed toward target-based drug design. Screening large libraries have greatly stimulated research toward effective anti-Ebola virus drug regimens. Current emphasis has been placed on the investigation of host proteins and druggable viral targets. There is a huge gap in the literature regarding guidelines in the discovery of Ebola virus inhibitors, which may be due to the lack of information on the Ebola drug targets, binding sites, and mechanism of action of the virus. This review focuses on Ebola virus inhibitors, drugs which could be repurposed to combat the Ebola virus, computational methods which study drug-target interactions as well as providing further insight into the mode of action of the Ebola virus. © 2016 John Wiley & Sons A/S.

A Distributed Agent Architecture for a Computer Virus Immune System

National Research Council Canada - National Science Library

Harmer, Paul

2000-01-01

.... Information protection and information assurance are vital components required for achieving superiority in the Infosphere, but these goals are threatened by the exponential birth rate of new computer viruses...

Modeling the state dependent impulse control for computer virus propagation under media coverage

Science.gov (United States)

Liang, Xiyin; Pei, Yongzhen; Lv, Yunfei

2018-02-01

A state dependent impulsive control model is proposed to model the spread of computer virus incorporating media coverage. By the successor function, the sufficient conditions for the existence and uniqueness of order-1 periodic solution are presented first. Secondly, for two classes of periodic solutions, the geometric property of successor function and the analogue of the Poincaré criterion are employed to obtain the stability results. These results show that the number of the infective computers is under the threshold all the time. Finally, the theoretic and numerical analysis show that media coverage can delay the spread of computer virus.

Unraveling the web of viroinformatics: computational tools and databases in virus research.

Science.gov (United States)

Sharma, Deepak; Priyadarshini, Pragya; Vrati, Sudhanshu

2015-02-01

The beginning of the second century of research in the field of virology (the first virus was discovered in 1898) was marked by its amalgamation with bioinformatics, resulting in the birth of a new domain--viroinformatics. The availability of more than 100 Web servers and databases embracing all or specific viruses (for example, dengue virus, influenza virus, hepatitis virus, human immunodeficiency virus [HIV], hemorrhagic fever virus [HFV], human papillomavirus [HPV], West Nile virus, etc.) as well as distinct applications (comparative/diversity analysis, viral recombination, small interfering RNA [siRNA]/short hairpin RNA [shRNA]/microRNA [miRNA] studies, RNA folding, protein-protein interaction, structural analysis, and phylotyping and genotyping) will definitely aid the development of effective drugs and vaccines. However, information about their access and utility is not available at any single source or on any single platform. Therefore, a compendium of various computational tools and resources dedicated specifically to virology is presented in this article. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Computational sensing of herpes simplex virus using a cost-effective on-chip microscope

KAUST Repository

Ray, Aniruddha

2017-07-03

Caused by the herpes simplex virus (HSV), herpes is a viral infection that is one of the most widespread diseases worldwide. Here we present a computational sensing technique for specific detection of HSV using both viral immuno-specificity and the physical size range of the viruses. This label-free approach involves a compact and cost-effective holographic on-chip microscope and a surface-functionalized glass substrate prepared to specifically capture the target viruses. To enhance the optical signatures of individual viruses and increase their signal-to-noise ratio, self-assembled polyethylene glycol based nanolenses are rapidly formed around each virus particle captured on the substrate using a portable interface. Holographic shadows of specifically captured viruses that are surrounded by these self-assembled nanolenses are then reconstructed, and the phase image is used for automated quantification of the size of each particle within our large field-of-view, ~30 mm2. The combination of viral immuno-specificity due to surface functionalization and the physical size measurements enabled by holographic imaging is used to sensitively detect and enumerate HSV particles using our compact and cost-effective platform. This computational sensing technique can find numerous uses in global health related applications in resource-limited environments.

Stability and Bifurcation Analysis of a Modified Epidemic Model for Computer Viruses

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Chuandong Li

2014-01-01

Full Text Available We extend the three-dimensional SIR model to four-dimensional case and then analyze its dynamical behavior including stability and bifurcation. It is shown that the new model makes a significant improvement to the epidemic model for computer viruses, which is more reasonable than the most existing SIR models. Furthermore, we investigate the stability of the possible equilibrium point and the existence of the Hopf bifurcation with respect to the delay. By analyzing the associated characteristic equation, it is found that Hopf bifurcation occurs when the delay passes through a sequence of critical values. An analytical condition for determining the direction, stability, and other properties of bifurcating periodic solutions is obtained by using the normal form theory and center manifold argument. The obtained results may provide a theoretical foundation to understand the spread of computer viruses and then to minimize virus risks.

ISCB Ebola Award for Important Future Research on the Computational Biology of Ebola Virus.

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Peter D. Karp

2015-01-01

Full Text Available Speed is of the essence in combating Ebola; thus, computational approaches should form a significant component of Ebola research. As for the development of any modern drug, computational biology is uniquely positioned to contribute through comparative analysis of the genome sequences of Ebola strains as well as 3-D protein modeling. Other computational approaches to Ebola may include large-scale docking studies of Ebola proteins with human proteins and with small-molecule libraries, computational modeling of the spread of the virus, computational mining of the Ebola literature, and creation of a curated Ebola database. Taken together, such computational efforts could significantly accelerate traditional scientific approaches. In recognition of the need for important and immediate solutions from the field of computational biology against Ebola, the International Society for Computational Biology (ISCB announces a prize for an important computational advance in fighting the Ebola virus. ISCB will confer the ISCB Fight against Ebola Award, along with a prize of US$2,000, at its July 2016 annual meeting (ISCB Intelligent Systems for Molecular Biology [ISMB] 2016, Orlando, Florida.

Stability and Hopf Bifurcation in a Computer Virus Model with Multistate Antivirus

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Tao Dong

2012-01-01

Full Text Available By considering that people may immunize their computers with countermeasures in susceptible state, exposed state and using anti-virus software may take a period of time, a computer virus model with time delay based on an SEIR model is proposed. We regard time delay as bifurcating parameter to study the dynamical behaviors which include local asymptotical stability and local Hopf bifurcation. By analyzing the associated characteristic equation, Hopf bifurcation occurs when time delay passes through a sequence of critical value. The linerized model and stability of the bifurcating periodic solutions are also derived by applying the normal form theory and the center manifold theorem. Finally, an illustrative example is also given to support the theoretical results.

A Novel Computer Virus Propagation Model under Security Classification

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Qingyi Zhu

2017-01-01

Full Text Available In reality, some computers have specific security classification. For the sake of safety and cost, the security level of computers will be upgraded with increasing of threats in networks. Here we assume that there exists a threshold value which determines when countermeasures should be taken to level up the security of a fraction of computers with low security level. And in some specific realistic environments the propagation network can be regarded as fully interconnected. Inspired by these facts, this paper presents a novel computer virus dynamics model considering the impact brought by security classification in full interconnection network. By using the theory of dynamic stability, the existence of equilibria and stability conditions is analysed and proved. And the above optimal threshold value is given analytically. Then, some numerical experiments are made to justify the model. Besides, some discussions and antivirus measures are given.

Computational fitness landscape for all gene-order permutations of an RNA virus.

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Kwang-il Lim

2009-02-01

Full Text Available How does the growth of a virus depend on the linear arrangement of genes in its genome? Answering this question may enhance our basic understanding of virus evolution and advance applications of viruses as live attenuated vaccines, gene-therapy vectors, or anti-tumor therapeutics. We used a mathematical model for vesicular stomatitis virus (VSV, a prototype RNA virus that encodes five genes (N-P-M-G-L, to simulate the intracellular growth of all 120 possible gene-order variants. Simulated yields of virus infection varied by 6,000-fold and were found to be most sensitive to gene-order permutations that increased levels of the L gene transcript or reduced levels of the N gene transcript, the lowest and highest expressed genes of the wild-type virus, respectively. Effects of gene order on virus growth also depended upon the host-cell environment, reflecting different resources for protein synthesis and different cell susceptibilities to infection. Moreover, by computationally deleting intergenic attenuations, which define a key mechanism of transcriptional regulation in VSV, the variation in growth associated with the 120 gene-order variants was drastically narrowed from 6,000- to 20-fold, and many variants produced higher progeny yields than wild-type. These results suggest that regulation by intergenic attenuation preceded or co-evolved with the fixation of the wild type gene order in the evolution of VSV. In summary, our models have begun to reveal how gene functions, gene regulation, and genomic organization of viruses interact with their host environments to define processes of viral growth and evolution.

How to stop e-mail spam, spyware, malware, computer viruses, and hackers from ruining your computer or network the complete guide for your home and work

CERN Document Server

Brown, Bruce

2010-01-01

It seems like everywhere you go on the Internet, there is spam, spyware, and the risk of viruses infecting your computer and ruining your online experience. In businesses alone, according to Nucleus Research Inc. spam costs more than 712 per employee each year in productivity and computing resources and the estimation on money lost by businesses due to computer viruses ranges between 100 million and 2 billion annually depending on how the total is calculated. This complete, revolutionary book has compiled all of the vital information you need to make sure that you are able to combat the risk

Comparative phyloinformatics of virus genes at micro and macro levels in a distributed computing environment.

Science.gov (United States)

Singh, Dadabhai T; Trehan, Rahul; Schmidt, Bertil; Bretschneider, Timo

2008-01-01

Preparedness for a possible global pandemic caused by viruses such as the highly pathogenic influenza A subtype H5N1 has become a global priority. In particular, it is critical to monitor the appearance of any new emerging subtypes. Comparative phyloinformatics can be used to monitor, analyze, and possibly predict the evolution of viruses. However, in order to utilize the full functionality of available analysis packages for large-scale phyloinformatics studies, a team of computer scientists, biostatisticians and virologists is needed--a requirement which cannot be fulfilled in many cases. Furthermore, the time complexities of many algorithms involved leads to prohibitive runtimes on sequential computer platforms. This has so far hindered the use of comparative phyloinformatics as a commonly applied tool in this area. In this paper the graphical-oriented workflow design system called Quascade and its efficient usage for comparative phyloinformatics are presented. In particular, we focus on how this task can be effectively performed in a distributed computing environment. As a proof of concept, the designed workflows are used for the phylogenetic analysis of neuraminidase of H5N1 isolates (micro level) and influenza viruses (macro level). The results of this paper are hence twofold. Firstly, this paper demonstrates the usefulness of a graphical user interface system to design and execute complex distributed workflows for large-scale phyloinformatics studies of virus genes. Secondly, the analysis of neuraminidase on different levels of complexity provides valuable insights of this virus's tendency for geographical based clustering in the phylogenetic tree and also shows the importance of glycan sites in its molecular evolution. The current study demonstrates the efficiency and utility of workflow systems providing a biologist friendly approach to complex biological dataset analysis using high performance computing. In particular, the utility of the platform Quascade

Hacking the lights out. The computer virus threat to the electrical grid; Angriff auf das Stromnetz

Energy Technology Data Exchange (ETDEWEB)

Nicol, David M. [Illinois Univ., Urbana-Champaign, IL (United States). Dept. of Electrical and Computer Engineering

2011-10-15

The Stuxnet virus which had penetrated in secured facilities to enrich uranium in Iran by June 2007 has made clear that a virus that was developed by experts for industrial automation may cause a large damage in a technical infrastructure. Our electricity network consists of a variety of networks whose components are monitored and controlled by computers or programmable logic controllers. This is a potential target of an attack for computers. Simulations suggest that a sophisticated attack can paralyze a large portion of the electricity networks. With this in mind the safety precautions are being greatly increased.

An intelligent and secure system for predicting and preventing Zika virus outbreak using Fog computing

Science.gov (United States)

Sareen, Sanjay; Gupta, Sunil Kumar; Sood, Sandeep K.

2017-10-01

Zika virus is a mosquito-borne disease that spreads very quickly in different parts of the world. In this article, we proposed a system to prevent and control the spread of Zika virus disease using integration of Fog computing, cloud computing, mobile phones and the Internet of things (IoT)-based sensor devices. Fog computing is used as an intermediary layer between the cloud and end users to reduce the latency time and extra communication cost that is usually found high in cloud-based systems. A fuzzy k-nearest neighbour is used to diagnose the possibly infected users, and Google map web service is used to provide the geographic positioning system (GPS)-based risk assessment to prevent the outbreak. It is used to represent each Zika virus (ZikaV)-infected user, mosquito-dense sites and breeding sites on the Google map that help the government healthcare authorities to control such risk-prone areas effectively and efficiently. The proposed system is deployed on Amazon EC2 cloud to evaluate its performance and accuracy using data set for 2 million users. Our system provides high accuracy of 94.5% for initial diagnosis of different users according to their symptoms and appropriate GPS-based risk assessment.

Online social networks—Paradise of computer viruses

Science.gov (United States)

Fan, W.; Yeung, K. H.

2011-01-01

Online social network services have attracted more and more users in recent years. So the security of social networks becomes a critical problem. In this paper, we propose a virus propagation model based on the application network of Facebook, which is the most popular among these social network service providers. We also study the virus propagation with an email virus model and compare the behaviors of a virus spreading on Facebook with the original email network. It is found that Facebook provides the same chance for a virus spreading while it gives a platform for application developers. And a virus will spread faster in the Facebook network if users of Facebook spend more time on it.

Computed tomography in young children with herpes simplex virus encephalitis

International Nuclear Information System (INIS)

Sugimoto, T.; Woo, M.; Okazaki, H.; Nishida, N.; Hara, T.; Yasuhara, A.; Kasahara, M.; Kobayashi, Y.

1985-01-01

Computed tomographic (CT) scans were obtained from eight infants and young children with herpes simplex virus encephalitis. In two cases the initial scan showed diffuse edematous changes as a mass effect without laterality. Unilateral localized low attenuation in the initial scan was evident 4 days after the onset in one patient, and high attenuation in the initial scan appeared on the 6th day in another patient, but in general, it was not possible to establish an early diagnosis of herpes simplex virus encephalitis from CT scan. In the longitudinal study the calcification with ventriculomegaly appeared in 3 of 5 survivors, and gyriform calcification in 2 of 3 patients, respectively. The appearance of multicystic encephalomalacia was evident in one patient 6 months after the onset of neonatal herpes simplex encephalitis. It is shown that the CT findings of neonates and young children with herpes simplex encephalitis are different from those of older children and adults, and the importance of longitudinal CT studies was stressed in clarifying the pathophysiology of the central nervous system involvement in survivors. (orig.)

Stability and Bifurcation of a Computer Virus Propagation Model with Delay and Incomplete Antivirus Ability

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Jianguo Ren

2014-01-01

Full Text Available A new computer virus propagation model with delay and incomplete antivirus ability is formulated and its global dynamics is analyzed. The existence and stability of the equilibria are investigated by resorting to the threshold value R0. By analysis, it is found that the model may undergo a Hopf bifurcation induced by the delay. Correspondingly, the critical value of the Hopf bifurcation is obtained. Using Lyapunov functional approach, it is proved that, under suitable conditions, the unique virus-free equilibrium is globally asymptotically stable if R01. Numerical examples are presented to illustrate possible behavioral scenarios of the mode.

Propagation Effect of a Virus Outbreak on a Network with Limited Anti-Virus Ability.

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Yonghong Xu

Full Text Available This paper describes a new computer virus spreading model which takes into account the possibility of a virus outbreak on a network with limited anti-virus ability. Then, the model is investigated for the existence of equilibria and their stabilities are proved and illustrated. Moreover, it is found that these two factors are not only relative to the threshold value determining whether the virus becomes extinct or not, but that they are also relative to the virus epidemic levels. Theoretical and experimental results indicate that, in some ways, it would be practically possible to eradicate the virus or suppress its prevalence below a suitable level. Consequently, some suggestions are proposed that may help eradicate or suppress virus propagation over a real computer network.

Computed Tomography Perfusion Usefulness in Early Imaging Diagnosis of Herpes Simplex Virus Encephalitis

International Nuclear Information System (INIS)

Marco de Lucas, E.; Mandly, Gonzalez A.; Gutierrez, A.; Sanchez, E.; Arnaiz, J.; Piedra, T.; Rodriguez, E.; Diez, C.

2006-01-01

An early diagnosis is crucial in herpes simplex virus encephalitis patients in order to institute acyclovir therapy and reduce mortality rates. Magnetic resonance imaging (MRI) is considered the gold standard for evaluation of these patients, but is frequently not available in the emergency setting. We report the first case of a computed tomography (CT) perfusion study that helped to establish a prompt diagnosis revealing abnormal increase of blood flow in the affected temporoparietal cortex at an early stage

Manifestations of infection by the novel influenza A (H1N1) virus at chest computed tomography

International Nuclear Information System (INIS)

Verrastro, Carlos Gustavo Yuji; D'Ippolito, Giuseppe

2009-01-01

Objective: the objective of this study was to describe chest computed tomography findings in confirmed cases of infection by the novel influenza A (H1N1) virus. Materials and methods: computed tomography studies of nine patients with laboratory-confirmed infection by the novel influenza A (H1N1) virus were consensually evaluated by three observers. The sample of the present study included five male and four female patients with ages ranging from 14 to 64 years (mean, 40 years). Four of the patients were previously healthy, four were kidney transplant recipients and one was pregnant at the time of diagnosis. Presence, extent and distribution of the following findings were evaluated: ground-glass opacities; centrilobular nodules; consolidation; interlobular septa thickening; pleural effusion; lymphadenopathy. Results: The most frequent findings were ground-glass opacities, centrilobular nodules and consolidations, present in nine (100%), five (55%) and four (44%) of cases, respectively. Pleural effusions and lymphadenopathy were less common findings, occurring in only two (22%) of the cases. Conclusion: ground-glass opacities, centrilobular nodules and consolidation were the most frequent findings in cases of infection by the novel influenza A (H1N1) virus. These changes are not typical or unique to this agent and may also occur in other viral or bacterial infections. (author)

PREDICTING ATTENUATION OF VIRUSES DURING PERCOLATION IN SOILS: 2. USER'S GUIDE TO THE VIRULO 1.0 COMPUTER MODEL

Science.gov (United States)

In the EPA document Predicting Attenuation of Viruses During Percolation in Soils 1. Probabilistic Model the conceptual, theoretical, and mathematical foundations for a predictive screening model were presented. In this current volume we present a User's Guide for the computer mo...

Single-photon emission computed tomography in human immunodeficiency virus encephalopathy: A preliminary report

International Nuclear Information System (INIS)

Masdeu, J.C.; Yudd, A.; Van Heertum, R.L.; Grundman, M.; Hriso, E.; O'Connell, R.A.; Luck, D.; Camli, U.; King, L.N.

1991-01-01

Depression or psychosis in a previously asymptomatic individual infected with the human immunodeficiency virus (HIV) may be psychogenic, related to brain involvement by the HIV or both. Although prognosis and treatment differ depending on etiology, computed tomography (CT) and magnetic resonance imaging (MRI) are usually unrevealing in early HIV encephalopathy and therefore cannot differentiate it from psychogenic conditions. Thirty of 32 patients (94%) with HIV encephalopathy had single-photon emission computed tomography (SPECT) findings that differed from the findings in 15 patients with non-HIV psychoses and 6 controls. SPECT showed multifocal cortical and subcortical areas of hypoperfusion. In 4 cases, cognitive improvement after 6-8 weeks of zidovudine (AZT) therapy was reflected in amelioration of SPECT findings. CT remained unchanged. SPECT may be a useful technique for the evaluation of HIV encephalopathy

Dynamics of a Computer Virus Propagation Model with Delays and Graded Infection Rate

Directory of Open Access Journals (Sweden)

Zizhen Zhang

2017-01-01

Full Text Available A four-compartment computer virus propagation model with two delays and graded infection rate is investigated in this paper. The critical values where a Hopf bifurcation occurs are obtained by analyzing the distribution of eigenvalues of the corresponding characteristic equation. In succession, direction and stability of the Hopf bifurcation when the two delays are not equal are determined by using normal form theory and center manifold theorem. Finally, some numerical simulations are also carried out to justify the obtained theoretical results.

Protecting computer-based medical devices: defending against viruses and other threats.

Science.gov (United States)

2005-07-01

The increasing integration of computer hardware has exposed medical devices to greater risks than ever before. More and more devices rely on commercial off-the-shelf software and operating systems, which are vulnerable to the increasing proliferation of viruses and other malicious programs that target computers. Therefore, it is necessary for hospitals to take steps such as those outlined in this article to ensure that their computer-based devices are made safe and continue to remain safe in the future. Maintaining the security of medical devices requires planning, careful execution, and a commitment of resources. A team should be created to develop a process for surveying the security status of all computerized devices in the hospital and making sure that patches and other updates are applied as needed. These patches and updates should be approved by the medical system supplier before being implemented. The team should consider using virtual local area networks to isolate susceptible devices on the hospital's network. All security measures should be carefully documented, and the documentation should be kept up-to-date. Above all, care must be taken to ensure that medical device security involves a collaborative, supportive partnership between the hospital's information technology staff and biomedical engineering personnel.

Computed tomography and magnetic resonance imaging findings in infants with microcephaly potentially related to congenital Zika virus infection

Energy Technology Data Exchange (ETDEWEB)

Peixoto Filho, Aníbal Araujo Alves; Freitas, Simone Baltar de; Ciosaki, Márcio Morikoshi; Oliveira, Lourenço Nogueira e; Santos Júnior, Onildo Tavares dos, E-mail: anibalpeixotof@gmail.com [Rede Sarah de Hospitais de Reabilitação, Salvador, BA (Brazil)

2018-03-15

The recent association between the increase in the number of neonates with microcephaly in northeastern Brazil and the outbreak of infection with the Zika virus, which has been occurring in the Americas, has been declared a public health emergency of international concern. The evidence that implicates the virus as the cause of this public health emergency has been demonstrated ever more consistently. This pictorial essay illustrates the imaging characteristics seen on computed tomography and magnetic resonance imaging scans of infants admitted to a rehabilitation hospital with a diagnosis of microcephaly and a maternal history of rash during pregnancy. (author)

Computed tomography and magnetic resonance imaging findings in infants with microcephaly potentially related to congenital Zika virus infection

International Nuclear Information System (INIS)

Peixoto Filho, Aníbal Araujo Alves; Freitas, Simone Baltar de; Ciosaki, Márcio Morikoshi; Oliveira, Lourenço Nogueira e; Santos Júnior, Onildo Tavares dos

2018-01-01

The recent association between the increase in the number of neonates with microcephaly in northeastern Brazil and the outbreak of infection with the Zika virus, which has been occurring in the Americas, has been declared a public health emergency of international concern. The evidence that implicates the virus as the cause of this public health emergency has been demonstrated ever more consistently. This pictorial essay illustrates the imaging characteristics seen on computed tomography and magnetic resonance imaging scans of infants admitted to a rehabilitation hospital with a diagnosis of microcephaly and a maternal history of rash during pregnancy. (author)

Crazy-paving sign in high-resolution computed tomography in parainfluenza virus pneumonia

Energy Technology Data Exchange (ETDEWEB)

Matsuno, Osamu [Department of Respiratory Disease, NHO National Osaka Minami Medical Center, Kido higashi machi 2-1, Kawachinagano City, Osaka 586-8521 (Japan)], E-mail: matsuno@ommc-hp.jp; Hayama, Yoshitomo; Honda, Hidehiro; Yamane, Hiroyuki; Yamamoto, Suguru; Ueno, Kiyonobu [Department of Respiratory Disease, NHO National Osaka Minami Medical Center, Kido higashi machi 2-1, Kawachinagano City, Osaka 586-8521 (Japan); Saeki, Yukihiko [Department of Clinical Research, NHO National Osaka Minami Medical Center, Kido higashi machi 2-1, Kawachinagano city, Osaka 586-8521 (Japan)

2010-05-15

The crazy-paving sign is the appearance of a smooth linear pattern superimposed on an area of ground-glass opacity on thin-section computed tomography (CT). A 69-year-old woman was admitted to our hospital for treatment of pneumonia. Thoracic CT showed a crazy-paving sign in the right lung field on admission. She received ceftriaxone and clarithromycin, and the symptoms and infiltration shadow promptly disappeared. Serologic testing revealed a greater than 4-fold increase in the IgG titer for parainfluenza virus I. To our knowledge, there is no previous report of the crazy-paving sign in associated with viral pneumonia in a non-immunocompromised host or with parainfluenza pneumonia.

Computer-Aided Design of an Epitope-Based Vaccine against Epstein-Barr Virus

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Julio Alonso-Padilla

2017-01-01

Full Text Available Epstein-Barr virus is a very common human virus that infects 90% of human adults. EBV replicates in epithelial and B cells and causes infectious mononucleosis. EBV infection is also linked to various cancers, including Burkitt’s lymphoma and nasopharyngeal carcinomas, and autoimmune diseases such as multiple sclerosis. Currently, there are no effective drugs or vaccines to treat or prevent EBV infection. Herein, we applied a computer-aided strategy to design a prophylactic epitope vaccine ensemble from experimentally defined T and B cell epitopes. Such strategy relies on identifying conserved epitopes in conjunction with predictions of HLA presentation for T cell epitope selection and calculations of accessibility and flexibility for B cell epitope selection. The T cell component includes 14 CD8 T cell epitopes from early antigens and 4 CD4 T cell epitopes, targeted during the course of a natural infection and providing a population protection coverage of over 95% and 81.8%, respectively. The B cell component consists of 3 experimentally defined B cell epitopes from gp350 plus 4 predicted B cell epitopes from other EBV envelope glycoproteins, all mapping in flexible and solvent accessible regions. We discuss the rationale for the formulation and possible deployment of this epitope vaccine ensemble.

Computational Identification of Antigenicity-Associated Sites in the Hemagglutinin Protein of A/H1N1 Seasonal Influenza Virus.

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Xiaowei Ren

Full Text Available The antigenic variability of influenza viruses has always made influenza vaccine development challenging. The punctuated nature of antigenic drift of influenza virus suggests that a relatively small number of genetic changes or combinations of genetic changes may drive changes in antigenic phenotype. The present study aimed to identify antigenicity-associated sites in the hemagglutinin protein of A/H1N1 seasonal influenza virus using computational approaches. Random Forest Regression (RFR and Support Vector Regression based on Recursive Feature Elimination (SVR-RFE were applied to H1N1 seasonal influenza viruses and used to analyze the associations between amino acid changes in the HA1 polypeptide and antigenic variation based on hemagglutination-inhibition (HI assay data. Twenty-three and twenty antigenicity-associated sites were identified by RFR and SVR-RFE, respectively, by considering the joint effects of amino acid residues on antigenic drift. Our proposed approaches were further validated with the H3N2 dataset. The prediction models developed in this study can quantitatively predict antigenic differences with high prediction accuracy based only on HA1 sequences. Application of the study results can increase understanding of H1N1 seasonal influenza virus antigenic evolution and accelerate the selection of vaccine strains.

Virus wars: using one virus to block the spread of another

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Matthew L. Paff

2016-06-01

Full Text Available The failure of traditional interventions to block and cure HIV infections has led to novel proposals that involve treating infections with therapeutic viruses–infectious viruses that specifically inhibit HIV propagation in the host. Early efforts in evaluating these proposals have been limited chiefly to mathematical models of dynamics, for lack of suitable empirical systems. Here we propose, develop and analyze an empirical system of a therapeutic virus that protects a host cell population against a lethal virus. The empirical system uses E. coli bacteria as the host cell population, an RNA phage as the lethal virus and a filamentous phage as the therapeutic virus. Basic dynamic properties are established for each virus alone and then together. Observed dynamics broadly agree with those predicted by a computer simulation model, although some differences are noted. Two cases of dynamics are contrasted, differing in whether the therapeutic virus is introduced before the lethal virus or after the lethal virus. The therapeutic virus increases in both cases but by different mechanisms. With the therapeutic virus introduced first, it spreads infectiously without any appreciable change in host dynamics. With the therapeutic virus introduced second, host abundance is depressed at the time therapy is applied; following an initial period of therapeutic virus spread by infection, the subsequent rise of protection is through reproduction by hosts already protected. This latter outcome is due to inheritance of the therapeutic virus state when the protected cell divides. Overall, the work establishes the feasibility and robustness to details of a viral interference using a therapeutic virus.

Design and implementation of anti-virus system in network

International Nuclear Information System (INIS)

An Dehai; Wu Chunzhen; Ma Lanxin

2004-01-01

This article focuses the computer worm-virus epidemic on the Internet and provides a way to restrain virus. This technique was made use of the anti virus system of IHEP network and it proved to be feasible and efficient. (authors)

Computational identification of mutually homologous Zika virus ...

African Journals Online (AJOL)

Background Zika virus (ZIKV) has been associated with a variety of neuropathologies, including microcephaly. We hypothesize that ZIKV genes activate host microRNAs (miRNAs) causing dysfunctional development of human fetal brains. Objectives/methods A bioinformatics search for miRNA genome-wide binding sites in ...

Zika Virus-Associated Cognitive Impairment in Adolescent, 2016.

Science.gov (United States)

Zucker, Jason; Neu, Natalie; Chiriboga, Claudia A; Hinton, Veronica J; Leonardo, Marc; Sheikh, Arif; Thakur, Kiran

2017-06-01

Incidence of neurologic manifestations associated with Zika virus infection has been increasing. In 2016, neuropsychological and cognitive changes developed in an adolescent after travel to a Zika virus-endemic area. Single-photon emission computed tomography and neuropsychological testing raised the possibility that Zika virus infection may lead to neuropsychiatric and cognitive symptoms.

Physician use of updated anti-virus software in a tertiary Nigerian ...

African Journals Online (AJOL)

While physicians are becoming increasingly dependent on computers and the internet, highly lethal malware continue to be loaded into cyberspace. We sought to assess the proportion of ... producers and anti-virus software developers. Keywords: Anti-virus software; Computer security; Updates; Physicians; Nigeria ...

A Computer Security Course in the Undergraduate Computer Science Curriculum.

Science.gov (United States)

Spillman, Richard

1992-01-01

Discusses the importance of computer security and considers criminal, national security, and personal privacy threats posed by security breakdown. Several examples are given, including incidents involving computer viruses. Objectives, content, instructional strategies, resources, and a sample examination for an experimental undergraduate computer…

Development of a generic virus behavioural detector: a preview ...

African Journals Online (AJOL)

The Generic Virus Behavioral Detector (GVBD) is a system (program) that monitors various system activities; reading and writing block of disks and memory and the use of Interrupts. A technique for its realisation is presented. Key Words: Computer virus, interrupts, handlers, GVBD (Generic Virus Behavioral Detector).

The Ghostly Virus Coming Out of the Machine

DEFF Research Database (Denmark)

Stephan, Matthias

Neal Stephensen’s Snow Crash presents a postcyberpunk narrative in which the dichotomy between the virtual and reality is blurred. The computer virus, Snow Crash, which threatens the Metaverse, is also capable of reaching out and ‘infecting’ hackers that simply read its code, blurring the ontolog......Neal Stephensen’s Snow Crash presents a postcyberpunk narrative in which the dichotomy between the virtual and reality is blurred. The computer virus, Snow Crash, which threatens the Metaverse, is also capable of reaching out and ‘infecting’ hackers that simply read its code, blurring...... experiences of entrapment in the virtual space, or the seemingly ‘wiping’ of hacker’s minds through the computer virus, which amount to the types of ‘invasive technologies’ which Luckhurst claims exist in the strand of science fiction which ‘shades into horror or Gothic writing.’ (5). Furthermore, in Snow...

Computational drug design strategies applied to the modelling of human immunodeficiency virus-1 reverse transcriptase inhibitors

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Lucianna Helene Santos

2015-11-01

Full Text Available Reverse transcriptase (RT is a multifunctional enzyme in the human immunodeficiency virus (HIV-1 life cycle and represents a primary target for drug discovery efforts against HIV-1 infection. Two classes of RT inhibitors, the nucleoside RT inhibitors (NRTIs and the nonnucleoside transcriptase inhibitors are prominently used in the highly active antiretroviral therapy in combination with other anti-HIV drugs. However, the rapid emergence of drug-resistant viral strains has limited the successful rate of the anti-HIV agents. Computational methods are a significant part of the drug design process and indispensable to study drug resistance. In this review, recent advances in computer-aided drug design for the rational design of new compounds against HIV-1 RT using methods such as molecular docking, molecular dynamics, free energy calculations, quantitative structure-activity relationships, pharmacophore modelling and absorption, distribution, metabolism, excretion and toxicity prediction are discussed. Successful applications of these methodologies are also highlighted.

Identifying a few foot-and-mouth disease virus signature nucleotide strings for computational genotyping

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Xu Lizhe

2008-06-01

Full Text Available Abstract Background Serotypes of the Foot-and-Mouth disease viruses (FMDVs were generally determined by biological experiments. The computational genotyping is not well studied even with the availability of whole viral genomes, due to uneven evolution among genes as well as frequent genetic recombination. Naively using sequence comparison for genotyping is only able to achieve a limited extent of success. Results We used 129 FMDV strains with known serotype as training strains to select as many as 140 most serotype-specific nucleotide strings. We then constructed a linear-kernel Support Vector Machine classifier using these 140 strings. Under the leave-one-out cross validation scheme, this classifier was able to assign correct serotype to 127 of these 129 strains, achieving 98.45% accuracy. It also assigned serotype correctly to an independent test set of 83 other FMDV strains downloaded separately from NCBI GenBank. Conclusion Computational genotyping is much faster and much cheaper than the wet-lab based biological experiments, upon the availability of the detailed molecular sequences. The high accuracy of our proposed method suggests the potential of utilizing a few signature nucleotide strings instead of whole genomes to determine the serotypes of novel FMDV strains.

Comparison of the structures of three circoviruses: chicken anemia virus, porcine circovirus type 2, and beak and feather disease virus.

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Crowther, R A; Berriman, J A; Curran, W L; Allan, G M; Todd, D

2003-12-01

Circoviruses are small, nonenveloped icosahedral animal viruses characterized by circular single-stranded DNA genomes. Their genomes are the smallest possessed by animal viruses. Infections with circoviruses, which can lead to economically important diseases, frequently result in virus-induced damage to lymphoid tissue and immunosuppression. Within the family Circoviridae, different genera are distinguished by differences in genomic organization. Thus, Chicken anemia virus is in the genus Gyrovirus, while porcine circoviruses and Beak and feather disease virus belong to the genus CIRCOVIRUS: Little is known about the structures of circoviruses. Accordingly, we investigated the structures of these three viruses with a view to determining whether they are related. Three-dimensional maps computed from electron micrographs showed that all three viruses have a T=1 organization with capsids formed from 60 subunits. Porcine circovirus type 2 and beak and feather disease virus show similar capsid structures with flat pentameric morphological units, whereas chicken anemia virus has stikingly different protruding pentagonal trumpet-shaped units. It thus appears that the structures of viruses in the same genus are related but that those of viruses in different genera are unrelated.

Radioimmunoassay of measles virus hemagglutinin protein G

International Nuclear Information System (INIS)

Lund, G.A.; Salmi, A.A.

1982-01-01

Guinea pig and rabbit antisera from animals immunized with purified measles virus hemagglutinin (G) protein were used to establish a solid-phase four-layer radioimmunoassay for quantitative measurement of the G protein. The sensitivity of the assay was 2 ng of purified G protein, and 200 μg of protein from uninfected Vero cells neither decreased the sensitivity nor reacted non-specifically in the assay. Radioimmunoassay standard dose-response curves were established and unknown values interpolated from these using the logit program of a desktop computer. Using this procedure, a measles virus growth curve in infected Vero cells was determined by measurement of G protein production. Under these same conditions, hemagglutination was not sensitive enough to detect early hemagglutinin production. Viral antigens in canine distemper virus, Newcastle disease virus, parainfluenza viruses 1-4, simian virus 5, and respiratory syncytial virus-infected cell lysates did not cross-react in the radioimmunoassay. A small degree of cross-reactivity was detected with mumps viral antigens, both with Vero cell-derived (wild-type strain) and egg-derived (Enders strain) purified virus preparations and with a cell lysate antigen prepared from wild-type mumps virus-infected Vero cells. (Auth.)

Radioimmunoassay of measles virus hemagglutinin protein G

Energy Technology Data Exchange (ETDEWEB)

Lund, G A; Salmi, A A [Turku Univ. (Finland)

1982-08-01

Guinea pig and rabbit antisera from animals immunized with purified measles virus hemagglutinin (G) protein were used to establish a solid-phase four-layer radioimmunoassay for quantitative measurement of the G protein. The sensitivity of the assay was 2 ng of purified G protein, and 200 ..mu..g of protein from uninfected Vero cells neither decreased the sensitivity nor reacted non-specifically in the assay. Radioimmunoassay standard dose-response curves were established and unknown values interpolated from these using the logit program of a desktop computer. Using this procedure, a measles virus growth curve in infected Vero cells was determined by measurement of G protein production. Under these same conditions, hemagglutination was not sensitive enough to detect early hemagglutinin production. Viral antigens in canine distemper virus, Newcastle disease virus, parainfluenza viruses 1-4, simian virus 5, and respiratory syncytial virus-infected cell lysates did not cross-react in the radioimmunoassay. A small degree of cross-reactivity was detected with mumps viral antigens, both with Vero cell-derived (wild-type strain) and egg-derived (Enders strain) purified virus preparations and with a cell lysate antigen prepared from wild-type mumps virus-infected Vero cells.

A tradeoff between the losses caused by computer viruses and the risk of the manpower shortage

NARCIS (Netherlands)

Bi, Jichao; Yang, L.; Yang, Xiaofan; Wu, Yingbo; Tang, Yuan Yan

2018-01-01

This article addresses the tradeoff between the losses caused by a new virus and the size of the team for developing an antivirus against the virus. First, an individual-level virus spreading model is proposed to capture the spreading process of the virus before the appearance of its natural

THE POSSIBLE COLLISIONS IN VIRUS INFECTION IMMUNODIAGNOSTICS AND VACCINATION

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E. P. Kharchenko

2016-01-01

Full Text Available Antibodies (Ab, especially natural, display multiple specificity not only due to intrinsic conformational dynamics. With computational analysis the distribution of identical and homologous peptides has been studied in surface proteins from RNA and DNA viruses of widely distributed infections. It was established that each virus protein shared the fragments homologous to other virus proteins that allowed to propose the existence of the peptide continuum of the protein relationship (PCPR. Possible manifestations of PCPR are multiple reactivity and autoreactivity in Ab and therefore it is not possible to consider the immune methods of virus identification as high reliable because of crossing interactions. The PCPR excludes the existence of 100% specificity in immune tests for virus identification. Immunodiagnostic collisions may occur either in identification of virus itself or identification of Ab to viruses. Also PCPR may be responsible for heterologous immunity and consequently the infection associated with severe pathology. The comparative analysis of peptide relationship of H1N1 influenza virus nucleoprotein and human proteins found out, beyond early described its common motif with human hypocretin receptor 2, peptides homologous to those in melanotonin and glutamate receptors and three ion channels. It allows to propose that the sleep disorder narcolepsy associated with Pandemrix vaccination (an adjuvanted, influenza pandemic vaccine and also with infection by influenza virus during the 2009 A(H1N1 influenza pandemic may be determined not only by Ab to the peptide motif common to influenza nucleoprotein and hypocretin receptor but also Ab to melanotonin and glutamate receptors and ion channels. Decreasing and even avoiding risks of complications from vaccination may be feasible by means of a computer analysis of vaccine proteins for the occurrence of epitopes homologous to the human protein those and particularly by an analysis of Ab profiles

Atypical manifestations of Epstein-Barr virus in children: a diagnostic challenge.

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Bolis, Vasileios; Karadedos, Christos; Chiotis, Ioannis; Chaliasos, Nikolaos; Tsabouri, Sophia

2016-01-01

Clarify the frequency and the pathophysiological mechanisms of the rare manifestations of Epstein-Barr virus infection. Original research studies published in English between 1985 and 2015 were selected through a computer-assisted literature search (PubMed and Scopus). Computer searches used combinations of key words relating to "EBV infections" and "atypical manifestation." Epstein-Barr virus is a herpes virus responsible for a lifelong latent infection in almost every adult. The primary infection concerns mostly children and presents with the clinical syndrome of infectious mononucleosis. However, Epstein-Barr virus infection may exhibit numerous rare, atypical and threatening manifestations. It may cause secondary infections and various complications of the respiratory, cardiovascular, genitourinary, gastrointestinal, and nervous systems. Epstein-Barr virus also plays a significant role in pathogenesis of autoimmune diseases, allergies, and neoplasms, with Burkitt lymphoma as the main representative of the latter. The mechanisms of these manifestations are still unresolved. Therefore, the main suggestions are direct viral invasion and chronic immune response due to the reactivation of the latent state of the virus, or even various DNA mutations. Physicians should be cautious about uncommon presentations of the viral infection and consider EBV as a causative agent when they encounter similar clinical pictures. Copyright © 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Ebola Virus and Marburg Virus

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Ebola virus and Marburg virus Overview Ebola virus and Marburg virus are related viruses that cause hemorrhagic fevers — illnesses marked by severe bleeding (hemorrhage), organ failure and, in many ...

Mayaro virus: the jungle flu

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Izurieta RO

2018-04-01

Full Text Available Ricardo O Izurieta,1 David A DeLacure,1 Andres Izurieta,2 Ismael A Hoare,1 Miguel Reina Ortiz,1,3 1Department of Global Health, College of Public Health, University of South Florida, Tampa, FL, USA; 2Department of Computer Science and Engineering, College of Engineering, University of South Florida, Tampa, FL, USA; 3Fundación Raíces, Esmeraldas, Ecuador Abstract: Mayaro fever is an emerging acute viral disease endemic in Central and South America. Mayaro virus (MAYV is classified in the Semliki Forest virus antigenic complex and shares similarities with the alphavirus Chikungunya virus and the flavivirus Dengue virus. MAYV is an arbovirus transmitted by Haemagogus janthinomys, with competence also demonstrated in Aedes aegypti, Aedes scapularis, and Anopheles quadrimaculatus. Outbreaks and small epidemics of Mayaro fever have occurred in several countries in northern South America and the Caribbean. In addition, travel-associated cases have been reported in European nationals returning from endemic areas. Clinical features of Mayaro fever include fever, chills, persistent arthralgia, retro-orbital pain, maculopapular rash, itching, dizziness, and, rarely, lymphadenopathy. Methods of control for MAYV are similar to those used for other sylvatic arboviruses. Although MAYV was discovered as long ago as the 1950s and continues to be prevalent in the tropical areas of the Americas, it remains neglected and under-studied. This paper provides a thorough and current review of the published MAYV literature ranging from its original description to modern outbreaks, and from the basic virus characteristics to the clinical and epidemiological aspects of this disease. Keywords: Mayaro virus, emerging arbovirus, dengue-like virus, arthrogenic virus

Computational analysis of perturbations in the post-fusion Dengue virus envelope protein highlights known epitopes and conserved residues in the Zika virus [version 2; referees: 3 approved

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Sandeep Chakraborty

2016-09-01

little emphasis in existing literature, are found to have significant electrostatic perturbation. Thus, a combination of different computational methods enable the rapid and rational detection of critical residues as epitopes in the search for an elusive therapy or vaccine that neutralizes multiple members of the Flaviviridae family. These secondary structures are conserved in the related Dengue virus (DENV, and possibly rationalize isolation techniques particle adsorption on magnetic beads coated with anionic polymers and anionic antiviral agents (viprolaxikine for DENV. These amphipathic α-helices could enable design of molecules for inhibiting α-helix mediated protein-protein interactions. Finally, comparison of these secondary structures in proteins from related families illuminate subtle changes in the proteins that might render them ineffective to previously successful drugs and vaccines, which are difficult to identify by a simple sequence or structural alignment. Finally, conflicting results about residues that are involved in neutralizing a DENV-E protein by the potent antibody 5J7 (PDB ID:3J6U are reported.

Structure of viruses: a short history.

Science.gov (United States)

Rossmann, Michael G

2013-05-01

This review is a partially personal account of the discovery of virus structure and its implication for virus function. Although I have endeavored to cover all aspects of structural virology and to acknowledge relevant individuals, I know that I have favored taking examples from my own experience in telling this story. I am anxious to apologize to all those who I might have unintentionally offended by omitting their work. The first knowledge of virus structure was a result of Stanley's studies of tobacco mosaic virus (TMV) and the subsequent X-ray fiber diffraction analysis by Bernal and Fankuchen in the 1930s. At about the same time it became apparent that crystals of small RNA plant and animal viruses could diffract X-rays, demonstrating that viruses must have distinct and unique structures. More advances were made in the 1950s with the realization by Watson and Crick that viruses might have icosahedral symmetry. With the improvement of experimental and computational techniques in the 1970s, it became possible to determine the three-dimensional, near-atomic resolution structures of some small icosahedral plant and animal RNA viruses. It was a great surprise that the protecting capsids of the first virus structures to be determined had the same architecture. The capsid proteins of these viruses all had a 'jelly-roll' fold and, furthermore, the organization of the capsid protein in the virus were similar, suggesting a common ancestral virus from which many of today's viruses have evolved. By this time a more detailed structure of TMV had also been established, but both the architecture and capsid protein fold were quite different to that of the icosahedral viruses. The small icosahedral RNA virus structures were also informative of how and where cellular receptors, anti-viral compounds, and neutralizing antibodies bound to these viruses. However, larger lipid membrane enveloped viruses did not form sufficiently ordered crystals to obtain good X-ray diffraction

Computational analysis of EBNA1 ``druggability'' suggests novel insights for Epstein-Barr virus inhibitor design

Science.gov (United States)

Gianti, Eleonora; Messick, Troy E.; Lieberman, Paul M.; Zauhar, Randy J.

2016-04-01

The Epstein-Barr Nuclear Antigen 1 (EBNA1) is a critical protein encoded by the Epstein-Barr Virus (EBV). During latent infection, EBNA1 is essential for DNA replication and transcription initiation of viral and cellular genes and is necessary to immortalize primary B-lymphocytes. Nonetheless, the concept of EBNA1 as drug target is novel. Two EBNA1 crystal structures are publicly available and the first small-molecule EBNA1 inhibitors were recently discovered. However, no systematic studies have been reported on the structural details of EBNA1 "druggable" binding sites. We conducted computational identification and structural characterization of EBNA1 binding pockets, likely to accommodate ligand molecules (i.e. "druggable" binding sites). Then, we validated our predictions by docking against a set of compounds previously tested in vitro for EBNA1 inhibition (PubChem AID-2381). Finally, we supported assessments of pocket druggability by performing induced fit docking and molecular dynamics simulations paired with binding affinity predictions by Molecular Mechanics Generalized Born Surface Area calculations for a number of hits belonging to druggable binding sites. Our results establish EBNA1 as a target for drug discovery, and provide the computational evidence that active AID-2381 hits disrupt EBNA1:DNA binding upon interacting at individual sites. Lastly, structural properties of top scoring hits are proposed to support the rational design of the next generation of EBNA1 inhibitors.

Radiomic analysis in prediction of Human Papilloma Virus status.

Science.gov (United States)

Yu, Kaixian; Zhang, Youyi; Yu, Yang; Huang, Chao; Liu, Rongjie; Li, Tengfei; Yang, Liuqing; Morris, Jeffrey S; Baladandayuthapani, Veerabhadran; Zhu, Hongtu

2017-12-01

Human Papilloma Virus (HPV) has been associated with oropharyngeal cancer prognosis. Traditionally the HPV status is tested through invasive lab test. Recently, the rapid development of statistical image analysis techniques has enabled precise quantitative analysis of medical images. The quantitative analysis of Computed Tomography (CT) provides a non-invasive way to assess HPV status for oropharynx cancer patients. We designed a statistical radiomics approach analyzing CT images to predict HPV status. Various radiomics features were extracted from CT scans, and analyzed using statistical feature selection and prediction methods. Our approach ranked the highest in the 2016 Medical Image Computing and Computer Assisted Intervention (MICCAI) grand challenge: Oropharynx Cancer (OPC) Radiomics Challenge, Human Papilloma Virus (HPV) Status Prediction. Further analysis on the most relevant radiomic features distinguishing HPV positive and negative subjects suggested that HPV positive patients usually have smaller and simpler tumors.

Zika Virus: Medical Countermeasure Development Challenges.

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Robert W Malone

2016-03-01

Full Text Available Reports of high rates of primary microcephaly and Guillain-Barré syndrome associated with Zika virus infection in French Polynesia and Brazil have raised concerns that the virus circulating in these regions is a rapidly developing neuropathic, teratogenic, emerging infectious public health threat. There are no licensed medical countermeasures (vaccines, therapies or preventive drugs available for Zika virus infection and disease. The Pan American Health Organization (PAHO predicts that Zika virus will continue to spread and eventually reach all countries and territories in the Americas with endemic Aedes mosquitoes. This paper reviews the status of the Zika virus outbreak, including medical countermeasure options, with a focus on how the epidemiology, insect vectors, neuropathology, virology and immunology inform options and strategies available for medical countermeasure development and deployment.Multiple information sources were employed to support the review. These included publically available literature, patents, official communications, English and Lusophone lay press. Online surveys were distributed to physicians in the US, Mexico and Argentina and responses analyzed. Computational epitope analysis as well as infectious disease outbreak modeling and forecasting were implemented. Field observations in Brazil were compiled and interviews conducted with public health officials.

Zika Virus: Medical Countermeasure Development Challenges

Science.gov (United States)

Malone, Robert W.; Homan, Jane; Callahan, Michael V.; Glasspool-Malone, Jill; Damodaran, Lambodhar; Schneider, Adriano De Bernardi; Zimler, Rebecca; Talton, James; Cobb, Ronald R.; Ruzic, Ivan; Smith-Gagen, Julie; Janies, Daniel; Wilson, James

2016-01-01

Introduction Reports of high rates of primary microcephaly and Guillain–Barré syndrome associated with Zika virus infection in French Polynesia and Brazil have raised concerns that the virus circulating in these regions is a rapidly developing neuropathic, teratogenic, emerging infectious public health threat. There are no licensed medical countermeasures (vaccines, therapies or preventive drugs) available for Zika virus infection and disease. The Pan American Health Organization (PAHO) predicts that Zika virus will continue to spread and eventually reach all countries and territories in the Americas with endemic Aedes mosquitoes. This paper reviews the status of the Zika virus outbreak, including medical countermeasure options, with a focus on how the epidemiology, insect vectors, neuropathology, virology and immunology inform options and strategies available for medical countermeasure development and deployment. Methods Multiple information sources were employed to support the review. These included publically available literature, patents, official communications, English and Lusophone lay press. Online surveys were distributed to physicians in the US, Mexico and Argentina and responses analyzed. Computational epitope analysis as well as infectious disease outbreak modeling and forecasting were implemented. Field observations in Brazil were compiled and interviews conducted with public health officials. PMID:26934531

Research Advances: DNA Computing Targets West Nile Virus, Other Deadly Diseases, and Tic-Tac-Toe; Marijuana Component May Offer Hope for Alzheimer's Disease Treatment; New Wound Dressing May Lead to Maggot Therapy--Without the Maggots

Science.gov (United States)

King, Angela G.

2007-01-01

This article presents three reports of research advances. The first report describes a deoxyribonucleic acid (DNA)-based computer that could lead to faster, more accurate tests for diagnosing West Nile Virus and bird flu. Representing the first "medium-scale integrated molecular circuit," it is the most powerful computing device of its type to…

Phospholipase A2 isolated from the venom of Crotalus durissus terrificus inactivates dengue virus and other enveloped viruses by disrupting the viral envelope.

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Vanessa Danielle Muller

Full Text Available The Flaviviridae family includes several virus pathogens associated with human diseases worldwide. Within this family, Dengue virus is the most serious threat to public health, especially in tropical and sub-tropical regions of the world. Currently, there are no vaccines or specific antiviral drugs against Dengue virus or against most of the viruses of this family. Therefore, the development of vaccines and the discovery of therapeutic compounds against the medically most important flaviviruses remain a global public health priority. We previously showed that phospholipase A2 isolated from the venom of Crotalus durissus terrificus was able to inhibit Dengue virus and Yellow fever virus infection in Vero cells. Here, we present evidence that phospholipase A2 has a direct effect on Dengue virus particles, inducing a partial exposure of genomic RNA, which strongly suggests inhibition via the cleavage of glycerophospholipids at the virus lipid bilayer envelope. This cleavage might induce a disruption of the lipid bilayer that causes a destabilization of the E proteins on the virus surface, resulting in inactivation. We show by computational analysis that phospholipase A2 might gain access to the Dengue virus lipid bilayer through the pores found on each of the twenty 3-fold vertices of the E protein shell on the virus surface. In addition, phospholipase A2 is able to inactivate other enveloped viruses, highlighting its potential as a natural product lead for developing broad-spectrum antiviral drugs.

Virus-Vectored Influenza Virus Vaccines

Science.gov (United States)

Tripp, Ralph A.; Tompkins, S. Mark

2014-01-01

Despite the availability of an inactivated vaccine that has been licensed for >50 years, the influenza virus continues to cause morbidity and mortality worldwide. Constant evolution of circulating influenza virus strains and the emergence of new strains diminishes the effectiveness of annual vaccines that rely on a match with circulating influenza strains. Thus, there is a continued need for new, efficacious vaccines conferring cross-clade protection to avoid the need for biannual reformulation of seasonal influenza vaccines. Recombinant virus-vectored vaccines are an appealing alternative to classical inactivated vaccines because virus vectors enable native expression of influenza antigens, even from virulent influenza viruses, while expressed in the context of the vector that can improve immunogenicity. In addition, a vectored vaccine often enables delivery of the vaccine to sites of inductive immunity such as the respiratory tract enabling protection from influenza virus infection. Moreover, the ability to readily manipulate virus vectors to produce novel influenza vaccines may provide the quickest path toward a universal vaccine protecting against all influenza viruses. This review will discuss experimental virus-vectored vaccines for use in humans, comparing them to licensed vaccines and the hurdles faced for licensure of these next-generation influenza virus vaccines. PMID:25105278

Opportunities for computer abuse

DEFF Research Database (Denmark)

Willison, Robert Andrew; Backhouse, James

2005-01-01

Systems risk refers to the likelihood that an IS is inadequately guarded against certain types of damage or loss. While risks are posed by acts of God, hackers and viruses, consideration should also be given to the `insider' threat of dishonest employees, intent on undertaking some form of computer...

Computational Analysis of the Interaction Energies between Amino Acid Residues of the Measles Virus Hemagglutinin and Its Receptors

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Fengqi Xu

2018-05-01

Full Text Available Measles virus (MV causes an acute and highly devastating contagious disease in humans. Employing the crystal structures of three human receptors, signaling lymphocyte-activation molecule (SLAM, CD46, and Nectin-4, in complex with the measles virus hemagglutinin (MVH, we elucidated computationally the details of binding energies between the amino acid residues of MVH and those of the receptors with an ab initio fragment molecular orbital (FMO method. The calculated inter-fragment interaction energies (IFIEs revealed a number of significantly interacting amino acid residues of MVH that played essential roles in binding to the receptors. As predicted from previously reported experiments, some important amino-acid residues of MVH were shown to be common but others were specific to interactions with the three receptors. Particularly, some of the (non-polar hydrophobic residues of MVH were found to be attractively interacting with multiple receptors, thus indicating the importance of the hydrophobic pocket for intermolecular interactions (especially in the case of Nectin-4. In contrast, the electrostatic interactions tended to be used for specific molecular recognition. Furthermore, we carried out FMO calculations for in silico experiments of amino acid mutations, finding reasonable agreements with virological experiments concerning the substitution effect of residues. Thus, the present study demonstrates that the electron-correlated FMO method is a powerful tool to search exhaustively for amino acid residues that contribute to interactions with receptor molecules. It is also applicable for designing inhibitors of MVH and engineered MVs for cancer therapy.

Proteotyping for the rapid identification of influenza virus and other biopathogens.

Science.gov (United States)

Downard, Kevin M

2013-11-21

The influenza virus is one of the most deadly infectious agents known to man and has been responsible for the deaths of some hundred million lives throughout human history. The need to rapidly and reliably survey circulating virus strains down to the molecular level is ever present. This tutorial describes the development and application of a new proteotyping approach that harnesses the power of high resolution of mass spectrometry to characterise the influenza virus, and by extension other bacterial and viral pathogens. The approach is shown to be able to type, subtype, and determine the lineage of human influenza virus strains through the detection of one or more signature peptide ions in the mass spectrum of whole virus digests. Pandemic strains can be similarly distinguished from seasonal ones, and new computer algorithms have been written to allow reassorted strains that pose the greatest pandemic risk to be rapidly identified from such datasets. The broader application of the approach is further demonstrated here for the parainfluenza virus, a virus which can be life threatening to children and presents similar clinical symptoms to influenza.

Computational elucidation of potential antigenic CTL epitopes in Ebola virus.

Science.gov (United States)

Dikhit, Manas R; Kumar, Santosh; Vijaymahantesh; Sahoo, Bikash R; Mansuri, Rani; Amit, Ajay; Yousuf Ansari, Md; Sahoo, Ganesh C; Bimal, Sanjiva; Das, Pradeep

2015-12-01

Cell-mediated immunity is important for the control of Ebola virus infection. We hypothesized that those HLA A0201 and HLA B40 restricted epitopes derived from Ebola virus proteins, would mount a good antigenic response. Here we employed an immunoinformatics approach to identify specific 9mer amino acid which may be capable of inducing a robust cell-mediated immune response in humans. We identified a set of 28 epitopes that had no homologs in humans. Specifically, the epitopes derived from NP, RdRp, GP and VP40 share population coverage of 93.40%, 84.15%, 74.94% and 77.12%, respectively. Based on the other HLA binding specificity and population coverage, seven novel promiscuous epitopes were identified. These 7 promiscuous epitopes from NP, RdRp and GP were found to have world-wide population coverage of more than 95% indicating their potential significance as useful candidates for vaccine design. Epitope conservancy analysis also suggested that most of the peptides are highly conserved (100%) in other virulent Ebola strain (Mayinga-76, Kikwit-95 and Makona-G3816- 2014) and can therefore be further investigated for their immunological relevance and usefulness as vaccine candidates. Copyright © 2015 Elsevier B.V. All rights reserved.

Top 10 Threats to Computer Systems Include Professors and Students

Science.gov (United States)

Young, Jeffrey R.

2008-01-01

User awareness is growing in importance when it comes to computer security. Not long ago, keeping college networks safe from cyberattackers mainly involved making sure computers around campus had the latest software patches. New computer worms or viruses would pop up, taking advantage of some digital hole in the Windows operating system or in…

Viral Diagnostics in Plants Using Next Generation Sequencing: Computational Analysis in Practice

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Susan Jones

2017-10-01

Full Text Available Viruses cause significant yield and quality losses in a wide variety of cultivated crops. Hence, the detection and identification of viruses is a crucial facet of successful crop production and of great significance in terms of world food security. Whilst the adoption of molecular techniques such as RT-PCR has increased the speed and accuracy of viral diagnostics, such techniques only allow the detection of known viruses, i.e., each test is specific to one or a small number of related viruses. Therefore, unknown viruses can be missed and testing can be slow and expensive if molecular tests are unavailable. Methods for simultaneous detection of multiple viruses have been developed, and (NGS is now a principal focus of this area, as it enables unbiased and hypothesis-free testing of plant samples. The development of NGS protocols capable of detecting multiple known and emergent viruses present in infected material is proving to be a major advance for crops, nuclear stocks or imported plants and germplasm, in which disease symptoms are absent, unspecific or only triggered by multiple viruses. Researchers want to answer the question “how many different viruses are present in this crop plant?” without knowing what they are looking for: RNA-sequencing (RNA-seq of plant material allows this question to be addressed. As well as needing efficient nucleic acid extraction and enrichment protocols, virus detection using RNA-seq requires fast and robust bioinformatics methods to enable host sequence removal and virus classification. In this review recent studies that use RNA-seq for virus detection in a variety of crop plants are discussed with specific emphasis on the computational methods implemented. The main features of a number of specific bioinformatics workflows developed for virus detection from NGS data are also outlined and possible reasons why these have not yet been widely adopted are discussed. The review concludes by discussing the future

Viral Diagnostics in Plants Using Next Generation Sequencing: Computational Analysis in Practice.

Science.gov (United States)

Jones, Susan; Baizan-Edge, Amanda; MacFarlane, Stuart; Torrance, Lesley

2017-01-01

Viruses cause significant yield and quality losses in a wide variety of cultivated crops. Hence, the detection and identification of viruses is a crucial facet of successful crop production and of great significance in terms of world food security. Whilst the adoption of molecular techniques such as RT-PCR has increased the speed and accuracy of viral diagnostics, such techniques only allow the detection of known viruses, i.e., each test is specific to one or a small number of related viruses. Therefore, unknown viruses can be missed and testing can be slow and expensive if molecular tests are unavailable. Methods for simultaneous detection of multiple viruses have been developed, and (NGS) is now a principal focus of this area, as it enables unbiased and hypothesis-free testing of plant samples. The development of NGS protocols capable of detecting multiple known and emergent viruses present in infected material is proving to be a major advance for crops, nuclear stocks or imported plants and germplasm, in which disease symptoms are absent, unspecific or only triggered by multiple viruses. Researchers want to answer the question "how many different viruses are present in this crop plant?" without knowing what they are looking for: RNA-sequencing (RNA-seq) of plant material allows this question to be addressed. As well as needing efficient nucleic acid extraction and enrichment protocols, virus detection using RNA-seq requires fast and robust bioinformatics methods to enable host sequence removal and virus classification. In this review recent studies that use RNA-seq for virus detection in a variety of crop plants are discussed with specific emphasis on the computational methods implemented. The main features of a number of specific bioinformatics workflows developed for virus detection from NGS data are also outlined and possible reasons why these have not yet been widely adopted are discussed. The review concludes by discussing the future directions of this

Computational identification of mutually homologous Zika virus ...

African Journals Online (AJOL)

Ewen McLean

2017-04-07

Apr 7, 2017 ... of Computer Science & Mathematics, Claflin University, Orangeburg, SC, USA. ABSTRACT. Background .... It is still unclear how and at what time of gestation ZIKV infects fetal brain cells, ..... Soc Interface. 2012;9:2708-2717.

Computer Security Day

CERN Multimedia

CERN Bulletin

2010-01-01

  Viruses, phishing, malware and cyber-criminals can all threaten your computer and your data, even at CERN! Experts will share their experience with you and offer solutions to keep your computer secure. Thursday, 10 June 2010, 9.30, Council Chamber Make a note in your diary! Presentations in French and English: How do hackers break into your computer? Quels sont les enjeux et conséquences des attaques informatiques contre le CERN ? How so criminals steal your money on the Internet? Comment utiliser votre ordinateur de manière sécurisée ? and a quiz: test your knowledge and win one of the many prizes that will be on offer! For more information and to follow the day's events via a live webcast go to: http://cern.ch/SecDay.  

IMG/VR: a database of cultured and uncultured DNA Viruses and retroviruses.

Science.gov (United States)

Paez-Espino, David; Chen, I-Min A; Palaniappan, Krishna; Ratner, Anna; Chu, Ken; Szeto, Ernest; Pillay, Manoj; Huang, Jinghua; Markowitz, Victor M; Nielsen, Torben; Huntemann, Marcel; K Reddy, T B; Pavlopoulos, Georgios A; Sullivan, Matthew B; Campbell, Barbara J; Chen, Feng; McMahon, Katherine; Hallam, Steve J; Denef, Vincent; Cavicchioli, Ricardo; Caffrey, Sean M; Streit, Wolfgang R; Webster, John; Handley, Kim M; Salekdeh, Ghasem H; Tsesmetzis, Nicolas; Setubal, Joao C; Pope, Phillip B; Liu, Wen-Tso; Rivers, Adam R; Ivanova, Natalia N; Kyrpides, Nikos C

2017-01-04

Viruses represent the most abundant life forms on the planet. Recent experimental and computational improvements have led to a dramatic increase in the number of viral genome sequences identified primarily from metagenomic samples. As a result of the expanding catalog of metagenomic viral sequences, there exists a need for a comprehensive computational platform integrating all these sequences with associated metadata and analytical tools. Here we present IMG/VR (https://img.jgi.doe.gov/vr/), the largest publicly available database of 3908 isolate reference DNA viruses with 264 413 computationally identified viral contigs from >6000 ecologically diverse metagenomic samples. Approximately half of the viral contigs are grouped into genetically distinct quasi-species clusters. Microbial hosts are predicted for 20 000 viral sequences, revealing nine microbial phyla previously unreported to be infected by viruses. Viral sequences can be queried using a variety of associated metadata, including habitat type and geographic location of the samples, or taxonomic classification according to hallmark viral genes. IMG/VR has a user-friendly interface that allows users to interrogate all integrated data and interact by comparing with external sequences, thus serving as an essential resource in the viral genomics community. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Characterization of antigenetic serotypes from the dengue virus in Venezuela by means of Grid Computing.

Science.gov (United States)

Isea, Raúl; Montes, Esther; Rubio-Montero, Antonio J; Rosales, José D; Rodríguez-Pascual, Manuel A; Mayo, Rafael

2010-01-01

This work determines the molecular epidemiology of dengue virus in Venezuela by means of phylogenetic calculations performed on the EELA-2 Grid infrastructure with the PhyloGrid application, an open source tool that allows users performing phylogeny reconstruction in their research. In this study, a total of 132 E nucleotide gene sequences of dengue virus from Venezuela recorded in GenBank(R) have been processed in order to reproduce and validate the topology described in the literature.

Nairobi sheep disease virus/Ganjam virus.

Science.gov (United States)

M D, Baron; B, Holzer

2015-08-01

Nairobi sheep disease virus (NSDV) is a tick-borne virus which causes a severe disease in sheep and goats, and has been responsible for several outbreaks of disease in East Africa. The virus is also found in the Indian subcontinent, where it is known as Ganjam virus. The virus only spreads through the feeding of competent infected ticks, and is therefore limited in its geographic distribution by the distribution of those ticks, Rhipicephalus appendiculata in Africa and Haemaphysalis intermedia in India. Animals bred in endemic areas do not normally develop disease, and the impact is therefore primarily on animals being moved for trade or breeding purposes. The disease caused by NSDV has similarities to several other ruminant diseases, and laboratory diagnosis is necessary for confirmation. There are published methods for diagnosis based on polymerase chain reaction, for virus growth in cell culture and for other simple diagnostic tests, though none has been commercialised. There is no established vaccine against NSDV, although cell-culture attenuated strains have been developed which show promise and could be put into field trials if it were deemed necessary. The virus is closely related to Crimean-Congo haemorrhagic fever virus, and studies on NSDV may therefore be useful in understanding this important human pathogen.

Toward a method for tracking virus evolutionary trajectory applied to the pandemic H1N1 2009 influenza virus.

Science.gov (United States)

Squires, R Burke; Pickett, Brett E; Das, Sajal; Scheuermann, Richard H

2014-12-01

In 2009 a novel pandemic H1N1 influenza virus (H1N1pdm09) emerged as the first official influenza pandemic of the 21st century. Early genomic sequence analysis pointed to the swine origin of the virus. Here we report a novel computational approach to determine the evolutionary trajectory of viral sequences that uses data-driven estimations of nucleotide substitution rates to track the gradual accumulation of observed sequence alterations over time. Phylogenetic analysis and multiple sequence alignments show that sequences belonging to the resulting evolutionary trajectory of the H1N1pdm09 lineage exhibit a gradual accumulation of sequence variations and tight temporal correlations in the topological structure of the phylogenetic trees. These results suggest that our evolutionary trajectory analysis (ETA) can more effectively pinpoint the evolutionary history of viruses, including the host and geographical location traversed by each segment, when compared against either BLAST or traditional phylogenetic analysis alone. Copyright © 2014 Elsevier B.V. All rights reserved.

Complex spatial dynamics of oncolytic viruses in vitro: mathematical and experimental approaches.

Directory of Open Access Journals (Sweden)

Dominik Wodarz

Full Text Available Oncolytic viruses replicate selectively in tumor cells and can serve as targeted treatment agents. While promising results have been observed in clinical trials, consistent success of therapy remains elusive. The dynamics of virus spread through tumor cell populations has been studied both experimentally and computationally. However, a basic understanding of the principles underlying virus spread in spatially structured target cell populations has yet to be obtained. This paper studies such dynamics, using a newly constructed recombinant adenovirus type-5 (Ad5 that expresses enhanced jellyfish green fluorescent protein (EGFP, AdEGFPuci, and grows on human 293 embryonic kidney epithelial cells, allowing us to track cell numbers and spatial patterns over time. The cells are arranged in a two-dimensional setting and allow virus spread to occur only to target cells within the local neighborhood. Despite the simplicity of the setup, complex dynamics are observed. Experiments gave rise to three spatial patterns that we call "hollow ring structure", "filled ring structure", and "disperse pattern". An agent-based, stochastic computational model is used to simulate and interpret the experiments. The model can reproduce the experimentally observed patterns, and identifies key parameters that determine which pattern of virus growth arises. The model is further used to study the long-term outcome of the dynamics for the different growth patterns, and to investigate conditions under which the virus population eliminates the target cells. We find that both the filled ring structure and disperse pattern of initial expansion are indicative of treatment failure, where target cells persist in the long run. The hollow ring structure is associated with either target cell extinction or low-level persistence, both of which can be viewed as treatment success. Interestingly, it is found that equilibrium properties of ordinary differential equations describing the

DIAGNOSTICS OF VIRUS PHYTOPATHOGENS FRUIT TREE PLUM POX VIRUS, PRUNUS NECROTIC RINGSPOT VIRUS AND PRUNUS DWARF VIRUS BY BIOLOGICAL AND MOLECULAR DIAGNOSTICS

Directory of Open Access Journals (Sweden)

Július Rozák

2013-02-01

Full Text Available The aim of this study was to determine the incidence of viral phytopathogen Plum pox virus, Prunus necrotic ringspot virus and Prunus dwarf virus in selected localities of Slovakia and diagnose them using a molecular and biological methods. Forty samples of fruit trees of the genus Prunus, twenty samples from intensive plantings and twenty samples from wild subject were analysed. Biological diagnostic by using biological indicators Prunus persica cv. GF 305, Prunus serrulata cv. Schirofugen and molecular diagnostic by mRT-PCR were applied. Five samples with Plum pox virus were infected. The two samples positive for Prunus necrotic ringspot virus and one sample for Prunus dwarf virus were confirmed. The two samples were found to be infected with two viruses Prunus necrotic ringspot virus and Prunus dwarf virus. This work focuses on two techniques, their application to the diagnosis of stone fruit viruses and their routinely used for sanitary and certification programmes.

Virus Particle Detection by Convolutional Neural Network in Transmission Electron Microscopy Images.

Science.gov (United States)

Ito, Eisuke; Sato, Takaaki; Sano, Daisuke; Utagawa, Etsuko; Kato, Tsuyoshi

2018-06-01

A new computational method for the detection of virus particles in transmission electron microscopy (TEM) images is presented. Our approach is to use a convolutional neural network that transforms a TEM image to a probabilistic map that indicates where virus particles exist in the image. Our proposed approach automatically and simultaneously learns both discriminative features and classifier for virus particle detection by machine learning, in contrast to existing methods that are based on handcrafted features that yield many false positives and require several postprocessing steps. The detection performance of the proposed method was assessed against a dataset of TEM images containing feline calicivirus particles and compared with several existing detection methods, and the state-of-the-art performance of the developed method for detecting virus was demonstrated. Since our method is based on supervised learning that requires both the input images and their corresponding annotations, it is basically used for detection of already-known viruses. However, the method is highly flexible, and the convolutional networks can adapt themselves to any virus particles by learning automatically from an annotated dataset.

Computer Registration Becoming Mandatory

CERN Multimedia

2003-01-01

Following the decision by the CERN Management Board (see Weekly Bulletin 38/2003), registration of all computers connected to CERN's network will be enforced and only registered computers will be allowed network access. The implementation has started with the IT buildings, continues with building 40 and the Prevessin site (as of Tuesday 4th November 2003), and will cover the whole of CERN before the end of this year. We therefore recommend strongly that you register all your computers in CERN's network database (Ethernet and wire-less cards) as soon as possible without waiting for the access restriction to take force. This will allow you accessing the network without interruption and help IT service providers to contact you in case of problems (security problems, viruses, etc.) • Users WITH a CERN computing account register at: http://cern.ch/register/ (CERN Intranet page) • Visitors WITHOUT a CERN computing account (e.g. short term visitors) register at: http://cern.ch/registerVisitorComp...

Computer Registration Becoming Mandatory

CERN Multimedia

2003-01-01

Following the decision by the CERN Management Board (see Weekly Bulletin 38/2003), registration of all computers connected to CERN's network will be enforced and only registered computers will be allowed network access. The implementation has started with the IT buildings, continues with building 40 and the Prevessin site (as of Tuesday 4th November 2003), and will cover the whole of CERN before the end of this year. We therefore recommend strongly that you register all your computers in CERN's network database including all network access cards (Ethernet AND wireless) as soon as possible without waiting for the access restriction to take force. This will allow you accessing the network without interruption and help IT service providers to contact you in case of problems (e.g. security problems, viruses, etc.) Users WITH a CERN computing account register at: http://cern.ch/register/ (CERN Intranet page) Visitors WITHOUT a CERN computing account (e.g. short term visitors) register at: http://cern.ch/regis...

Computer Security: DNS to the rescue!

CERN Multimedia

Stefan Lueders, Computer Security Team

2016-01-01

Why you should be grateful to the Domain Name System at CERN.   Incidents involving so-called “drive-by” infections and “ransomware” are on the rise. Whilst an up-to-date and fully patched operating system is essential; whilst running anti-virus software with current virus signature files is a must; whilst “stop --- think --- don’t click” surely helps, we can still go one step further in better protecting your computers: DNS to the rescue. The DNS, short for Domain Name System, translates the web address you want to visit (like “http://cern.ch”) to a machine-readable format (the IP address, here: “188.184.9.234”). For years, we have automatically monitored the DNS translation requests made by your favourite web browser (actually by your operating system, but that doesn’t matter here), and we have automatically informed you if your computer tried to access a website known to hos...

Oncogenic Viruses and Breast Cancer: Mouse Mammary Tumor Virus (MMTV, Bovine Leukemia Virus (BLV, Human Papilloma Virus (HPV, and Epstein–Barr Virus (EBV

Directory of Open Access Journals (Sweden)

James S. Lawson

2018-01-01

Full Text Available BackgroundAlthough the risk factors for breast cancer are well established, namely female gender, early menarche and late menopause plus the protective influence of early pregnancy, the underlying causes of breast cancer remain unknown. The development of substantial recent evidence indicates that a handful of viruses may have a role in breast cancer. These viruses are mouse mammary tumor virus (MMTV, bovine leukemia virus (BLV, human papilloma viruses (HPVs, and Epstein–Barr virus (EBV-also known as human herpes virus type 4. Each of these viruses has documented oncogenic potential. The aim of this review is to inform the scientific and general community about this recent evidence.The evidenceMMTV and human breast cancer—the evidence is detailed and comprehensive but cannot be regarded as conclusive. BLV and human breast cancer—the evidence is limited. However, in view of the emerging information about BLV in human breast cancer, it is prudent to encourage the elimination of BLV in cattle, particularly in the dairy industry. HPVs and breast cancer—the evidence is substantial but not conclusive. The availability of effective preventive vaccines is a major advantage and their use should be encouraged. EBV and breast cancer—the evidence is also substantial but not conclusive. Currently, there are no practical means of either prevention or treatment. Although there is evidence of genetic predisposition, and cancer in general is a culmination of events, there is no evidence that inherited genetic traits are causal.ConclusionThe influence of oncogenic viruses is currently the major plausible hypothesis for a direct cause of human breast cancer.

Oncogenic Viruses and Breast Cancer: Mouse Mammary Tumor Virus (MMTV), Bovine Leukemia Virus (BLV), Human Papilloma Virus (HPV), and Epstein-Barr Virus (EBV).

Science.gov (United States)

Lawson, James S; Salmons, Brian; Glenn, Wendy K

2018-01-01

Although the risk factors for breast cancer are well established, namely female gender, early menarche and late menopause plus the protective influence of early pregnancy, the underlying causes of breast cancer remain unknown. The development of substantial recent evidence indicates that a handful of viruses may have a role in breast cancer. These viruses are mouse mammary tumor virus (MMTV), bovine leukemia virus (BLV), human papilloma viruses (HPVs), and Epstein-Barr virus (EBV-also known as human herpes virus type 4). Each of these viruses has documented oncogenic potential. The aim of this review is to inform the scientific and general community about this recent evidence. MMTV and human breast cancer-the evidence is detailed and comprehensive but cannot be regarded as conclusive. BLV and human breast cancer-the evidence is limited. However, in view of the emerging information about BLV in human breast cancer, it is prudent to encourage the elimination of BLV in cattle, particularly in the dairy industry. HPVs and breast cancer-the evidence is substantial but not conclusive. The availability of effective preventive vaccines is a major advantage and their use should be encouraged. EBV and breast cancer-the evidence is also substantial but not conclusive. Currently, there are no practical means of either prevention or treatment. Although there is evidence of genetic predisposition, and cancer in general is a culmination of events, there is no evidence that inherited genetic traits are causal. The influence of oncogenic viruses is currently the major plausible hypothesis for a direct cause of human breast cancer.

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

OpenAIRE

Savithri, HS; Murthy, MRN

1983-01-01

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

A Constructive Induction Approach to Computer Immunology

Science.gov (United States)

1999-03-01

LVM98] Lamont, Gary B., David A. Van Veldhuizen , and Robert E Marmelstein, A Distributed Architecture for a Self-Adaptive Computer Virus...Artificial Intelligence, Herndon, VA, 1995. [MVL98] Marmelstein, Robert E., David A. Van Veldhuizen , and Gary B. Lamont. Modeling & Analysis

Computational sensing of herpes simplex virus using a cost-effective on-chip microscope

KAUST Repository

Ray, Aniruddha; Daloglu, Mustafa Ugur; Ho, Joslynn; Torres, Avee; Mcleod, Euan; Ozcan, Aydogan

2017-01-01

of specifically captured viruses that are surrounded by these self-assembled nanolenses are then reconstructed, and the phase image is used for automated quantification of the size of each particle within our large field-of-view, ~30 mm2. The combination of viral

pLoc-mVirus: Predict subcellular localization of multi-location virus proteins via incorporating the optimal GO information into general PseAAC.

Science.gov (United States)

Cheng, Xiang; Xiao, Xuan; Chou, Kuo-Chen

2017-09-10

Knowledge of subcellular locations of proteins is crucially important for in-depth understanding their functions in a cell. With the explosive growth of protein sequences generated in the postgenomic age, it is highly demanded to develop computational tools for timely annotating their subcellular locations based on the sequence information alone. The current study is focused on virus proteins. Although considerable efforts have been made in this regard, the problem is far from being solved yet. Most existing methods can be used to deal with single-location proteins only. Actually, proteins with multi-locations may have some special biological functions. This kind of multiplex proteins is particularly important for both basic research and drug design. Using the multi-label theory, we present a new predictor called "pLoc-mVirus" by extracting the optimal GO (Gene Ontology) information into the general PseAAC (Pseudo Amino Acid Composition). Rigorous cross-validation on a same stringent benchmark dataset indicated that the proposed pLoc-mVirus predictor is remarkably superior to iLoc-Virus, the state-of-the-art method in predicting virus protein subcellular localization. To maximize the convenience of most experimental scientists, a user-friendly web-server for the new predictor has been established at http://www.jci-bioinfo.cn/pLoc-mVirus/, by which users can easily get their desired results without the need to go through the complicated mathematics involved. Copyright © 2017 Elsevier B.V. All rights reserved.

The study of virus structure and function: a personal history

Science.gov (United States)

Rossmann, Michael G.

2014-09-01

I describe my gradually evolving role as a scientist from my birth in Frankfurt (Germany) to my education in the UK, my post-doc years and my experiences as an independent investigator at Purdue University1. I discuss the significance of my post-doctoral work in Minnesota where I had my first encounter with an electronic computer and subsequently in Cambridge where I participated in the first structure determination of proteins. After six years back in England my family moved to Indiana (USA) where my home remains to this day. At Purdue University I first studied the structure of enzymes and in the process I discovered the organization and slow evolution of protein domains, each with a specific function. With this success I started what had been on my mind already for a long time, namely the structural analysis of viruses. Initially we studied plant viruses but then switched to small RNA animal viruses, discovering that some plant and animal RNA viruses have closely similar structures and therefore presumably had a common evolutionary origin. Next I became interested in somewhat larger viruses that had lipid membrane envelopes. In turn that has led to the study of very large dsDNA viruses as big as small bacteria as well as studies of bacterial viruses that require complex molecular motors for different parts of their life cycle. While developing crystallographic techniques for the study of viruses it has become progressively more apparent that electron microscopy is an important new tool that is likely to eclipse x-ray crystallography in the next decade.

Computational Modelling and Optimal Control of Ebola Virus Disease with non-Linear Incidence Rate

Science.gov (United States)

Takaidza, I.; Makinde, O. D.; Okosun, O. K.

2017-03-01

The 2014 Ebola outbreak in West Africa has exposed the need to connect modellers and those with relevant data as pivotal to better understanding of how the disease spreads and quantifying the effects of possible interventions. In this paper, we model and analyse the Ebola virus disease with non-linear incidence rate. The epidemic model created is used to describe how the Ebola virus could potentially evolve in a population. We perform an uncertainty analysis of the basic reproductive number R 0 to quantify its sensitivity to other disease-related parameters. We also analyse the sensitivity of the final epidemic size to the time control interventions (education, vaccination, quarantine and safe handling) and provide the cost effective combination of the interventions.

Melaleuca alternifolia Concentrate Inhibits in Vitro Entry of Influenza Virus into Host Cells

Directory of Open Access Journals (Sweden)

Lifang Jiang

2013-08-01

Full Text Available Influenza virus causes high morbidity among the infected population annually and occasionally the spread of pandemics. Melaleuca alternifolia Concentrate (MAC is an essential oil derived from a native Australian tea tree. Our aim was to investigate whether MAC has any in vitro inhibitory effect on influenza virus infection and what mechanism does the MAC use to fight the virus infection. In this study, the antiviral activity of MAC was examined by its inhibition of cytopathic effects. In silico prediction was performed to evaluate the interaction between MAC and the viral haemagglutinin. We found that when the influenza virus was incubated with 0.010% MAC for one hour, no cytopathic effect on MDCK cells was found after the virus infection and no immunofluorescence signal was detected in the host cells. Electron microscopy showed that the virus treated with MAC retained its structural integrity. By computational simulations, we found that terpinen-4-ol, which is the major bioactive component of MAC, could combine with the membrane fusion site of haemagglutinin. Thus, we proved that MAC could prevent influenza virus from entering the host cells by disturbing the normal viral membrane fusion procedure.

Comparative analysis of chrysanthemum transcriptome in response to three RNA viruses: Cucumber mosaic virus, Tomato spotted wilt virus and Potato virus X.

Science.gov (United States)

Choi, Hoseong; Jo, Yeonhwa; Lian, Sen; Jo, Kyoung-Min; Chu, Hyosub; Yoon, Ju-Yeon; Choi, Seung-Kook; Kim, Kook-Hyung; Cho, Won Kyong

2015-06-01

The chrysanthemum is one of popular flowers in the world and a host for several viruses. So far, molecular interaction studies between the chrysanthemum and viruses are limited. In this study, we carried out a transcriptome analysis of chrysanthemum in response to three different viruses including Cucumber mosaic virus (CMV), Tomato spotted wilt virus (TSWV) and Potato virus X (PVX). A chrysanthemum 135K microarray derived from expressed sequence tags was successfully applied for the expression profiles of the chrysanthemum at early stage of virus infection. Finally, we identified a total of 125, 70 and 124 differentially expressed genes (DEGs) for CMV, TSWV and PVX, respectively. Many DEGs were virus specific; however, 33 DEGs were commonly regulated by three viruses. Gene ontology (GO) enrichment analysis identified a total of 132 GO terms, and of them, six GO terms related stress response and MCM complex were commonly identified for three viruses. Several genes functioning in stress response such as chitin response and ethylene mediated signaling pathway were up-regulated indicating their involvement in establishment of host immune system. In particular, TSWV infection significantly down-regulated genes related to DNA metabolic process including DNA replication, chromatin organization, histone modification and cytokinesis, and they are mostly targeted to nucleosome and MCM complex. Taken together, our comparative transcriptome analysis revealed several genes related to hormone mediated viral stress response and DNA modification. The identified chrysanthemums genes could be good candidates for further functional study associated with resistant to various plant viruses.

Stochastic acidification, activation of hemagglutinin and escape of influenza viruses from an endosome

Science.gov (United States)

Lagache, Thibault; Sieben, Christian; Meyer, Tim; Herrmann, Andreas; Holcman, David

2017-06-01

Influenza viruses enter the cell inside an endosome. During the endosomal journey, acidification triggers a conformational change of the virus spike protein hemagglutinin (HA) that results in escape of the viral genome from the endosome into the cytoplasm. It is still unclear how the interplay between acidification and HA conformation changes affects the kinetics of the viral endosomal escape. We develop here a stochastic model to estimate the change of conformation of HAs inside the endosome nanodomain. Using a Markov process, we model the arrival of protons to HA binding sites and compute the kinetics of their accumulation. We compute the Mean First Passage Time (MFPT) of the number of HA bound sites to a threshold, which is used to estimate the HA activation rate for a given pH concentration. The present analysis reveals that HA proton binding sites possess a high chemical barrier, ensuring a stability of the spike protein at sub-acidic pH. We predict that activating more than 3 adjacent HAs is necessary to trigger endosomal fusion and this configuration prevents premature release of viruses from early endosomes

The importance of trust in computer security

DEFF Research Database (Denmark)

Jensen, Christian D.

2014-01-01

The computer security community has traditionally regarded security as a “hard” property that can be modelled and formally proven under certain simplifying assumptions. Traditional security technologies assume that computer users are either malicious, e.g. hackers or spies, or benevolent, competent...... and well informed about the security policies. Over the past two decades, however, computing has proliferated into all aspects of modern society and the spread of malicious software (malware) like worms, viruses and botnets have become an increasing threat. This development indicates a failure in some...... of the fundamental assumptions that underpin existing computer security technologies and that a new view of computer security is long overdue. In this paper, we examine traditionalmodels, policies and mechanisms of computer security in order to identify areas where the fundamental assumptions may fail. In particular...

A mixed SIR-SIS model to contain a virus spreading through networks with two degrees

Science.gov (United States)

Essouifi, Mohamed; Achahbar, Abdelfattah

Due to the fact that the “nodes” and “links” of real networks are heterogeneous, to model computer viruses prevalence throughout the Internet, we borrow the idea of the reduced scale free network which was introduced recently. The purpose of this paper is to extend the previous deterministic two subchains of Susceptible-Infected-Susceptible (SIS) model into a mixed Susceptible-Infected-Recovered and Susceptible-Infected-Susceptible (SIR-SIS) model to contain the computer virus spreading over networks with two degrees. Moreover, we develop its stochastic counterpart. Due to the high protection and security taken for hubs class, we suggest to treat it by using SIR epidemic model rather than the SIS one. The analytical study reveals that the proposed model admits a stable viral equilibrium. Thus, it is shown numerically that the mean dynamic behavior of the stochastic model is in agreement with the deterministic one. Unlike the infection densities i2 and i which both tend to a viral equilibrium for both approaches as in the previous study, i1 tends to the virus-free equilibrium. Furthermore, since a proportion of infectives are recovered, the global infection density i is minimized. Therefore, the permanent presence of viruses in the network due to the lower-degree nodes class. Many suggestions are put forward for containing viruses propagation and minimizing their damages.

Mathematical analysis of dengue virus antibody dynamics

Science.gov (United States)

Perera, Sulanie; Perera, SSN

2018-03-01

Dengue is a mosquito borne viral disease causing over 390 million infections worldwide per annum. Even though information on how infection is controlled and eradicated from the body is lacking, antibodies are thought to play a major role in clearing the virus. In this paper, a non-linear conceptual dynamical model with humoral immune response and absorption effect has been proposed for primary dengue infection. We have included the absorption of pathogens into uninfected cells since this effect causes the virus density in the blood to decrease. The time delay that arises in the production of antibodies was accounted and is introduced through a continuous function. The basic reproduction number R0 is computed and a detailed stability analysis is done. Three equilibrium states, namely the infection free equilibrium, no immune equilibrium and the endemic equilibrium were identified and the existence and the stability conditions of these steady states were obtained. Numerical simulations proved the results that were obtained. By establishing the characteristic equation of the model at infection free equilibrium, it was observed that the infection free equilibrium is locally asymptotically stable if R0 1. Stability regions are identified for infection free equilibrium state with respect to the external variables and it is observed as the virus burst rate increases, the stability regions would decrease. These results implied that for higher virus burst rates, other conditions in the body must be strong enough to eliminate the disease completely from the host. The effect of time delay of antibody production on virus dynamics is discussed. It was seen that as the time delay in production of antibodies increases, the time for viral decline also increased. Also it was observed that the virus count goes to negligible levels within 7 - 14 days after the onset of symptoms as seen in dengue infections.

Virus Database and Online Inquiry System Based on Natural Vectors.

Science.gov (United States)

Dong, Rui; Zheng, Hui; Tian, Kun; Yau, Shek-Chung; Mao, Weiguang; Yu, Wenping; Yin, Changchuan; Yu, Chenglong; He, Rong Lucy; Yang, Jie; Yau, Stephen St

2017-01-01

We construct a virus database called VirusDB (http://yaulab.math.tsinghua.edu.cn/VirusDB/) and an online inquiry system to serve people who are interested in viral classification and prediction. The database stores all viral genomes, their corresponding natural vectors, and the classification information of the single/multiple-segmented viral reference sequences downloaded from National Center for Biotechnology Information. The online inquiry system serves the purpose of computing natural vectors and their distances based on submitted genomes, providing an online interface for accessing and using the database for viral classification and prediction, and back-end processes for automatic and manual updating of database content to synchronize with GenBank. Submitted genomes data in FASTA format will be carried out and the prediction results with 5 closest neighbors and their classifications will be returned by email. Considering the one-to-one correspondence between sequence and natural vector, time efficiency, and high accuracy, natural vector is a significant advance compared with alignment methods, which makes VirusDB a useful database in further research.

Quantifying antiviral activity optimizes drug combinations against hepatitis C virus infection

Energy Technology Data Exchange (ETDEWEB)

Koizumi, Yoshiki [School of Medicine, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Ishikawa, Japan; Nakajim, Syo [Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan; Department of Applied Biological Sciences, Faculty of Science and Technology, Tokyo University of Sciences, Chiba, J; Ohash, Hirofumi [Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan: Department of Applied Biological Sciences, Faculty of Science and Technology, Tokyo University of Sciences, Chiba, J; Tanaka, Yasuhito [Department of Virology and Liver Unit, Nagoya City University Graduate School of Medicinal Sciences, Nagoya, Japan; Wakita, Takaji [Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan; Perelson, Alan S. [Los Alamos National Laboratory; Iwami, Shingo [Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan: PRESTO, JST, Saitama, Japan: CREST, JST, Saitama, Japan; Watashi, Koichi [Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan: Department of Applied Biological Sciences, Faculty of Science and Technology, Tokyo University of Sciences, Chiba, J

2016-03-21

Cell culture study combing a mathematical model and computer simulation quantifies the anti-hepatitis C virus drug efficacy at any concentrations and any combinations in preclinical settings, and can obtain rich basic evidences for selecting optimal treatments prior to costly clinical trials.

Creation of Functional Viruses from Non-Functional cDNA Clones Obtained from an RNA Virus Population by the Use of Ancestral Reconstruction

DEFF Research Database (Denmark)

Fahnøe, Ulrik; Pedersen, Anders Gorm; Dräger, Carolin

2015-01-01

necessarily be the descendant of a functional ancestor, we hypothesized that it should be possible to produce functional clones by reconstructing ancestral sequences. To test this we used phylogenetic methods to infer two ancestral sequences, which were then reconstructed as cDNA clones. Viruses rescued from...... the reconstructed cDNAs were tested in cell culture and pigs. Both reconstructed ancestral genomes proved functional, and displayed distinct phenotypes in vitro and in vivo. We suggest that reconstruction of ancestral viruses is a useful tool for experimental and computational investigations of virulence and viral...... evolution. Importantly, ancestral reconstruction can be done even on the basis of a set of sequences that all correspond to non-functional variants....

Ecogenomics and potential biogeochemical impacts of globally abundant ocean viruses.

Science.gov (United States)

Roux, Simon; Brum, Jennifer R; Dutilh, Bas E; Sunagawa, Shinichi; Duhaime, Melissa B; Loy, Alexander; Poulos, Bonnie T; Solonenko, Natalie; Lara, Elena; Poulain, Julie; Pesant, Stéphane; Kandels-Lewis, Stefanie; Dimier, Céline; Picheral, Marc; Searson, Sarah; Cruaud, Corinne; Alberti, Adriana; Duarte, Carlos M; Gasol, Josep M; Vaqué, Dolors; Bork, Peer; Acinas, Silvia G; Wincker, Patrick; Sullivan, Matthew B

2016-09-29

Ocean microbes drive biogeochemical cycling on a global scale. However, this cycling is constrained by viruses that affect community composition, metabolic activity, and evolutionary trajectories. Owing to challenges with the sampling and cultivation of viruses, genome-level viral diversity remains poorly described and grossly understudied, with less than 1% of observed surface-ocean viruses known. Here we assemble complete genomes and large genomic fragments from both surface- and deep-ocean viruses sampled during the Tara Oceans and Malaspina research expeditions, and analyse the resulting 'global ocean virome' dataset to present a global map of abundant, double-stranded DNA viruses complete with genomic and ecological contexts. A total of 15,222 epipelagic and mesopelagic viral populations were identified, comprising 867 viral clusters (defined as approximately genus-level groups). This roughly triples the number of known ocean viral populations and doubles the number of candidate bacterial and archaeal virus genera, providing a near-complete sampling of epipelagic communities at both the population and viral-cluster level. We found that 38 of the 867 viral clusters were locally or globally abundant, together accounting for nearly half of the viral populations in any global ocean virome sample. While two-thirds of these clusters represent newly described viruses lacking any cultivated representative, most could be computationally linked to dominant, ecologically relevant microbial hosts. Moreover, we identified 243 viral-encoded auxiliary metabolic genes, of which only 95 were previously known. Deeper analyses of four of these auxiliary metabolic genes (dsrC, soxYZ, P-II (also known as glnB) and amoC) revealed that abundant viruses may directly manipulate sulfur and nitrogen cycling throughout the epipelagic ocean. This viral catalog and functional analyses provide a necessary foundation for the meaningful integration of viruses into ecosystem models where they

Anti-Dengue Virus Constituents from Formosan Zoanthid Palythoa mutuki

Science.gov (United States)

Lee, Jin-Ching; Chang, Fang-Rong; Chen, Shu-Rong; Wu, Yu-Hsuan; Hu, Hao-Chun; Wu, Yang-Chang; Backlund, Anders; Cheng, Yuan-Bin

2016-01-01

A new marine ecdysteroid with an α-hydroxy group attaching at C-4 instead of attaching at C-2 and C-3, named palythone A (1), together with eight known compounds (2–9) were obtained from the ethanolic extract of the Formosan zoanthid Palythoa mutuki. The structures of those compounds were mainly determined by NMR spectroscopic data analyses. The absolute configuration of 1 was further confirmed by comparing experimental and calculated circular dichroism (CD) spectra. Anti-dengue virus 2 activity and cytotoxicity of five isolated compounds were evaluated using virus infectious system and [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assays, respectively. As a result, peridinin (9) exhibited strong antiviral activity (IC50 = 4.50 ± 0.46 μg/mL), which is better than that of the positive control, 2′CMC. It is the first carotene-like substance possessing anti-dengue virus activity. In addition, the structural diversity and bioactivity of the isolates were compared by using a ChemGPS–NP computational analysis. The ChemGPS–NP data suggested natural products with anti-dengue virus activity locate closely in the chemical space. PMID:27517937

Competitive virus assay method for titration of noncytopathogenic bovine viral diarrhea viruses (END⁺ and END⁻ viruses).

Science.gov (United States)

Muhsen, Mahmod; Ohi, Kota; Aoki, Hiroshi; Ikeda, Hidetoshi; Fukusho, Akio

2013-03-01

A new, reliable and secure virus assay method, named the competitive virus assay (CVA) method, has been established for the titration of bovine viral diarrhea viruses (BVDVs) that either show the exaltation of Newcastle disease virus (END) phenomenon or heterologous interference phenomenon (but not the END phenomenon). This method is based on the principle of (1) homologous interference between BVDVs, by using BVDV RK13/E(-) or BVDV RK13/E(+) strains as competitor virus, and (2) END phenomenon and heterologous interference, by using attenuated Newcastle disease virus (NDV) TCND strain as challenge virus. In titration of BVDV END(+) and BVDV END(-) viruses, no significant difference in estimated virus titer was observed between CVA and conventional methods. CVA method demonstrated comparable levels of sensitivity and accuracy as conventional END and interference methods, which require the use of a velogenic Miyadera strain of NDV and vesicular stomatitis virus (VSV), both of which are agents of high-risk diseases. As such, the CVA method is a safer alternative, with increased bio-safety and bio-containment, through avoidance of virulent strains that are commonly employed with conventional methods. Copyright © 2012 Elsevier B.V. All rights reserved.

Immunofluorescence Plaque Assay for African Swine Fever Virus

Science.gov (United States)

Tessler, J.; Hess, W. R.; Pan, I. C.; Trautman, R.

1974-01-01

Suitably diluted cell culture adapted African swine fever virus preparations were inoculated on VERO cell monolayers and grown on coverslips. Gum tragacanth was used as an overlay. After three days incubation at 37°C the infected cultures were fixed with acetone and stained with fluorescent antibody conjugate. Fluorescing plaques consisted of 20-30 infected cells. Three statistical criteria for a quantitatively reliable assay were met: the Poisson distribution for plaque counts, linearity of the relationship between the concentration of virus and the plaque count and reproducibility of replicate titrations. The method is suitable for counts up to at least 70 plaques per 5 cm2 coverslip and computed titers are reproducible within 0.16 log units with a total of 300 plaques enumerated. PMID:4279763

A computational approach identifies two regions of Hepatitis C Virus E1 protein as interacting domains involved in viral fusion process

Directory of Open Access Journals (Sweden)

El Sawaf Gamal

2009-07-01

Full Text Available Abstract Background The E1 protein of Hepatitis C Virus (HCV can be dissected into two distinct hydrophobic regions: a central domain containing an hypothetical fusion peptide (FP, and a C-terminal domain (CT comprising two segments, a pre-anchor and a trans-membrane (TM region. In the currently accepted model of the viral fusion process, the FP and the TM regions are considered to be closely juxtaposed in the post-fusion structure and their physical interaction cannot be excluded. In the present study, we took advantage of the natural sequence variability present among HCV strains to test, by purely sequence-based computational tools, the hypothesis that in this virus the fusion process involves the physical interaction of the FP and CT regions of E1. Results Two computational approaches were applied. The first one is based on the co-evolution paradigm of interacting peptides and consequently on the correlation between the distance matrices generated by the sequence alignment method applied to FP and CT primary structures, respectively. In spite of the relatively low random genetic drift between genotypes, co-evolution analysis of sequences from five HCV genotypes revealed a greater correlation between the FP and CT domains than respect to a control HCV sequence from Core protein, so giving a clear, albeit still inconclusive, support to the physical interaction hypothesis. The second approach relies upon a non-linear signal analysis method widely used in protein science called Recurrence Quantification Analysis (RQA. This method allows for a direct comparison of domains for the presence of common hydrophobicity patterns, on which the physical interaction is based upon. RQA greatly strengthened the reliability of the hypothesis by the scoring of a lot of cross-recurrences between FP and CT peptides hydrophobicity patterning largely outnumbering chance expectations and pointing to putative interaction sites. Intriguingly, mutations in the CT

Engineering of avian influenza virus detection system in a patient's body

International Nuclear Information System (INIS)

Budi Santoso; Romadhon; Sukandar, Istofa

2010-01-01

The avian influenza virus detection equipment in a patient's body has been made. Currently, detection of avian influenza virus carried out by expensive laboratory equipment's, so only certain hospitals can perform this detection. This developing equipment is expected to be cheaper than existing equipment and the diagnosis can be known immediately. The sensing device is made using the principle of nuclear radiation detection. Radiation comes from a drunk labelled tamiflu (oseltamivir) which is drunk to the patient. Tamiflu is a drug to catch H5N1 viruses in a patient's body. A labelled tamiflu is tamiflu which is labelled by 1-131 radioisotopes. The presence of virus in the body is proportional to the amount of radiation captured by the detector. The equipment is composed of a Geiger-Mueller (GM) pancake detector type, a signal processor, a counter, and a data processor (computer). The GM detector converts the radiation that comes into electrical signals. Electrical signal is then converted into TTL level pulses by the signal processor. Pulse counting results are processed by data processor. The total count is proportional to the amount of virus captured by labelled tamiflu. The measurement threshold can be set by medical officer through software. At a certain threshold can be inferred identified patients infected with avian influenza virus. If the measurement below the threshold means that the patient is still within safe limits. This equipment is expected to create avian influenza virus detection system that cheaply and quickly so that more and more hospitals are using to detect the avian influenza virus. (author)

Zika virus disease

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Adel I Al-Afaleq

2017-01-01

Full Text Available The Zika virus is an arbovirus belonging to the virus family Flaviviridae. The virus was isolated in 1947 from a rhesus monkey in the Zika Forest of Uganda. The virus causes sporadic mild human infections in Africa and later in Asia. However, by 2007 a major shift in its infection pattern was noticed and thousands of human infections were reported in the State of Yap and Federated States of Micronesia. In the last 3 years, major outbreaks have continued to occur and the virus has spread to several Pacific and American countries. These outbreaks were mostly asymptomatic; however, there were more severe clinical signs associated with the infections. Those signs included microcephaly and Guillain–Barre syndrome. It is believed that various species of mosquitoes can biologically transmit the virus. However, Aedes aegypti is most widely associated with the Zika virus. Recently, new modes of virus transmission have been reported, including mother-to-fetus, sexual, blood transfusion, animal bites, laboratory exposure and breast milk. Differential diagnosis is very important as some other arboviruses such as yellow fever virus, West Nile virus, dengue virus, and chikungunya virus have similar clinical manifestations to the Zika virus infection as well as relating serologically to some of these viruses. Established laboratory diagnostic tests to detect the Zika virus are limited, with reverse transcription polymerase chain reaction being the most widely used test. Taking into consideration the quickness of the spread of infection, size of the infected population and change of the infection severity pattern, the Zika virus infection merits collective efforts on all levels to prevent and control the disease. Limited research work and data, concurrent infection with other arboviruses, involvement of biological vectors, mass crowd events, human and trade movements and lack of vaccines are some of the challenges that we face in our efforts to prevent and

Dengue virus receptor

OpenAIRE

Hidari, Kazuya I.P.J.; Suzuki, Takashi

2011-01-01

Dengue virus is an arthropod-borne virus transmitted by Aedes mosquitoes. Dengue virus causes fever and hemorrhagic disorders in humans and non-human primates. Direct interaction of the virus introduced by a mosquito bite with host receptor molecule(s) is crucial for virus propagation and the pathological progression of dengue diseases. Therefore, elucidation of the molecular mechanisms underlying the interaction between dengue virus and its receptor(s) in both humans and mosquitoes is essent...

High-resolution computed tomography findings of influenza virus pneumonia. A comparative study between seasonal and novel (H1N1) influenza virus pneumonia

International Nuclear Information System (INIS)

Tanaka, Nobuyuki; Kunihiro, Yoshie; Matsunaga, Naofumi; Hasegawa, Shunji; Ichiyama, Takashi; Emoto, Takuya; Suda, Hiroki

2012-01-01

The purpose of this study was to evaluate the high-resolution computed tomography (HRCT) findings of novel influenza virus (n-IFV) pneumonia and compare them with the findings for seasonal (s-IFV) pneumonia. We evaluated 29 cases of pure IFV pneumonia that occurred between 1990 and 2010. We evaluated the existence, extent, and patterns of HRCT findings and compared these features between s-IFV and n-IFV. Consolidation was less frequent in s-IFV than in n-IFV (40.0 vs. 84.2%, respectively; p=0.014). Consolidation with a loss of volume was frequent in n-IFV (62.5%). There was no significant difference in the occurrence of ground-glass opacity (GGO) between s-IFV and n-IFV (100 vs. 84.2%, respectively). GGO with reticular opacities was more frequent in s-IFV than in n-IFV (70.0 vs. 25.0%, respectively; p=0.024). The frequency of nodules was not significantly different between the two groups. The mosaic pattern was more frequent in s-IFV than in n-IFV patients (80.0 vs. 15.8%, respectively; p=0.0007). Mucoid impaction was more frequent in patients with n-IFV than with s-IFV (52.6 vs. 10.0%, respectively; p=0.025). Consolidation and mucoid impaction were more frequent in n-IFV, whereas GGO with reticular opacities and a mosaic pattern occurred more frequently in s-IFV; otherwise, there were no significant differences between the two groups. (author)

The mathematics of virus shell assembly. Progress report 1995--1996

Energy Technology Data Exchange (ETDEWEB)

Berger, B.

1996-08-01

This research focuses on applying computational and mathematical techniques to problems in biology, and more specifically to problems in protein folding. Significant progress has been made in the following areas relating to virus shell assembly: the local rules theory has been further developed; development has begun on a second-generation simulator which provides a more physically realistic model of assembly, collaborative efforts have continued with an experimental biologist to verify and inspire the local rules theory; an investigation has been initiated into the mechanics of virus shell assembly; laboratory experiments have been conducted on bacteriophage T4 which verify that the previously believed structure for the core may be incorrect.

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 can lead ...

Hepatitis E virus coinfection with hepatotropic viruses in Egyptian children.

Science.gov (United States)

Zaki, Maysaa El Sayed; Salama, Osama Saad; Mansour, Fathy Awaad; Hossein, Shaimaa

2008-06-01

Major hepatotropic viruses continue to be important causes of acute viral hepatitis in developing countries. This work was carried out to detect the seroprevalence of hepatitis E virus (HEV) markers in children with acute viral hepatitis due to hepatotropic viruses (A, B and C) and non-A, non-B, non-C acute hepatitis, and to ascertain the influence of HEV superinfection in individuals infected with hepatitis viruses (A, B and C). We studied prospectively 162 children with sporadic acute hepatitis who reported to our hospital. Thirteen healthy controls were also included in the study. Laboratory investigations were performed, including complete liver function tests. Complete serological profiles for hepatitis viruses A, B, C and E were evaluated. HEV immunoglobulin G was detected with highest percentage among patients with hepatitis B (56.7%), followed by patients with hepatitis C virus (52.0%), hepatitis A virus (34.1%) and combined hepatitis B and C viruses (30.0%). The detection rate among patients with non-A, non-B, non-C hepatitis was 7.1%. HEV immunoglobulin M was found in 4.5% of hepatitis A virus patients and in 3.3% of hepatitis B patients. The prevalence of HEV immunoglobulin G and immunoglobulin M correlated with the levels of hepatic aspartate aminotransferase and alanine aminotransferase in patients with dual markers of infection with hepatitis E and other viruses compared to patients with acute hepatitis due to A and C viruses. HEV serological markers are common among children with acute viral hepatitis, especially from hepatitis C and B viruses. There may be increased sensitivity to HEV coinfection in association with hepatitis B and C infections. Dual infection with HEV and other hepatotropic viruses was associated with greater elevation of aspartate and alanine aminotransferases.

Physician use of updated anti-virus software in a tertiary Nigerian ...

African Journals Online (AJOL)

While physicians are becoming increasingly dependent on computers and the internet, highly lethal malware continue to be loaded into cyberspace. We sought to assess the proportion of physicians with updated anti-virus software in Jos University Teaching Hospital Nigeria and to determine perceived barriers to getting ...

Evidence of pervasive biologically functional secondary structures within the genomes of eukaryotic single-stranded DNA viruses.

Science.gov (United States)

Muhire, Brejnev Muhizi; Golden, Michael; Murrell, Ben; Lefeuvre, Pierre; Lett, Jean-Michel; Gray, Alistair; Poon, Art Y F; Ngandu, Nobubelo Kwanele; Semegni, Yves; Tanov, Emil Pavlov; Monjane, Adérito Luis; Harkins, Gordon William; Varsani, Arvind; Shepherd, Dionne Natalie; Martin, Darren Patrick

2014-02-01

Single-stranded DNA (ssDNA) viruses have genomes that are potentially capable of forming complex secondary structures through Watson-Crick base pairing between their constituent nucleotides. A few of the structural elements formed by such base pairings are, in fact, known to have important functions during the replication of many ssDNA viruses. Unknown, however, are (i) whether numerous additional ssDNA virus genomic structural elements predicted to exist by computational DNA folding methods actually exist and (ii) whether those structures that do exist have any biological relevance. We therefore computationally inferred lists of the most evolutionarily conserved structures within a diverse selection of animal- and plant-infecting ssDNA viruses drawn from the families Circoviridae, Anelloviridae, Parvoviridae, Nanoviridae, and Geminiviridae and analyzed these for evidence of natural selection favoring the maintenance of these structures. While we find evidence that is consistent with purifying selection being stronger at nucleotide sites that are predicted to be base paired than at sites predicted to be unpaired, we also find strong associations between sites that are predicted to pair with one another and site pairs that are apparently coevolving in a complementary fashion. Collectively, these results indicate that natural selection actively preserves much of the pervasive secondary structure that is evident within eukaryote-infecting ssDNA virus genomes and, therefore, that much of this structure is biologically functional. Lastly, we provide examples of various highly conserved but completely uncharacterized structural elements that likely have important functions within some of the ssDNA virus genomes analyzed here.

Phytophthora viruses.

Science.gov (United States)

Cai, Guohong; Hillman, Bradley I

2013-01-01

Phytophthora sp. is a genus in the oomycetes, which are similar to filamentous fungi in morphology and habitat, but phylogenetically more closely related to brown algae and diatoms and fall in the kingdom Stramenopila. In the past few years, several viruses have been characterized in Phytophthora species, including four viruses from Phytophthora infestans, the late blight pathogen, and an endornavirus from an unnamed Phytophthora species from Douglas fir. Studies on Phytophthora viruses have revealed several interesting systems. Phytophthora infestans RNA virus 1 (PiRV-1) and PiRV-2 are likely the first members of two new virus families; studies on PiRV-3 support the establishment of a new virus genus that is not affiliated with established virus families; PiRV-4 is a member of Narnaviridae, most likely in the genus Narnavirus; and Phytophthora endornavirus 1 (PEV1) was the first nonplant endornavirus at the time of reporting. Viral capsids have not been found in any of the above-mentioned viruses. PiRV-1 demonstrated a unique genome organization that requires further examination, and PiRV-2 may have played a role in late blight resurgence in 1980s-1990s. Copyright © 2013 Elsevier Inc. All rights reserved.

Viruses infecting reptiles.

Science.gov (United States)

Marschang, Rachel E

2011-11-01

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

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.

Characterization of uncultivable bat influenza virus using a replicative synthetic virus.

Directory of Open Access Journals (Sweden)

Bin Zhou

2014-10-01

Full Text Available Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV. Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1. This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2 showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses.

Characterization of uncultivable bat influenza virus using a replicative synthetic virus.

Science.gov (United States)

Zhou, Bin; Ma, Jingjiao; Liu, Qinfang; Bawa, Bhupinder; Wang, Wei; Shabman, Reed S; Duff, Michael; Lee, Jinhwa; Lang, Yuekun; Cao, Nan; Nagy, Abdou; Lin, Xudong; Stockwell, Timothy B; Richt, Juergen A; Wentworth, David E; Ma, Wenjun

2014-10-01

Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV). Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1). This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2) showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses.

A stochastic model for simulation of the economic consequences of bovine virus diarrhoea virus infection in a dairy herd

DEFF Research Database (Denmark)

Sørensen, J.T.; Enevoldsen, Carsten; Houe, H.

1995-01-01

A dynamic, stochastic model simulating the technical and economic consequences of bovine virus diarrhoea virus (BVDV) infections for a dairy cattle herd for use on a personal computer was developed. The production and state changes of the herd were simulated by state changes of the individual cows...... and heifers. All discrete events at the cow level were triggered stochastically. Each cow and heifer was characterized by state variables such as stage of lactation, parity, oestrous status, decision for culling, milk production potential, and immune status for BVDV. The model was controlled by 170 decision...... variables describing biologic and management variables including 21 decision variables describing the effect of BVDV infection on the production of the individual animal. Two markedly different scenarios were simulated to demonstrate the behaviour of the developed model and the potentials of the applied...

OCCURRENCE OF SMALL HOMOLOGOUS AND COMPLEMENTARY FRAGMENTS IN HUMAN VIRUS GENOMES AND THEIR POSSIBLE ROLE

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E. P. Kharchenko

2017-01-01

Full Text Available With computer analysis occurrence of small homologous and complementary fragments (21 nucleotides in length has been studied in genomes of 14 human viruses causing most dangerous infections. The sample includes viruses with (+ and (– single stranded RNA and DNA-containing hepatitis A virus. Analysis of occurrence of homologous sequences has shown the existence two extreme situations. On the one hand, the same virus contains homologous sequences to almost all other viruses (for example, Ebola virus, severe acute respiratory syndrome-related coronavirus, and mumps virus, and numerous homologous sequences to the same other virus (especially in severe acute respiratory syndrome-related coronavirus to Dengue virus and in Ebola virus to poliovirus. On the other hand, there are rare occurrence and not numerous homologous sequences in genomes of other viruses (rubella virus, hepatitis A virus, and hepatitis B virus. Similar situation exists for occurrence of complementary sequences. Rubella virus, the genome of which has the high content of guanine and cytosine, has no complementary sequences to almost all other viruses. Most viruses have moderate level of occurrence for homologous and complementary sequences. Autocomplementary sequences are numerous in most viruses and one may suggest that the genome of single stranded RNA viruses has branched secondary structure. In addition to possible role in recombination among strains autocomplementary sequences could be regulators of translation rate of virus proteins and determine its optimal proportion in virion assembly with genome and mRNA folding. Occurrence of small homologous and complementary sequences in RNA- and DNA-containing viruses may be the result of multiple recombinations in the past and the present and determine their adaptation and variability. Recombination may take place in coinfection of human and/or common hosts. Inclusion of homologous and complementary sequences into genome could not

Prevalence of human immunodeficiency virus, hepatitis C virus ...

African Journals Online (AJOL)

Background. Human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and syphilis remain major infections around the world. In Angola, about 166 000 individuals are living with HIV, representing a prevalence of 1.98% in adults between 15 and 49 years of age. In a 2003 study in Luanda, 4.5% ...

Structural lability of Barley stripe mosaic virus virions.

Directory of Open Access Journals (Sweden)

Valentin V Makarov

Full Text Available Virions of Barley stripe mosaic virus (BSMV were neglected for more than thirty years after their basic properties were determined. In this paper, the physicochemical characteristics of BSMV virions and virion-derived viral capsid protein (CP were analyzed, namely, the absorption and intrinsic fluorescence spectra, circular dichroism spectra, differential scanning calorimetry curves, and size distributions by dynamic laser light scattering. The structural properties of BSMV virions proved to be intermediate between those of Tobacco mosaic virus (TMV, a well-characterized virus with rigid rod-shaped virions, and flexuous filamentous plant viruses. The BSMV virions were found to be considerably more labile than expected from their rod-like morphology and a distant sequence relation of the BSMV and TMV CPs. The circular dichroism spectra of BSMV CP subunits incorporated into the virions, but not subunits of free CP, demonstrated a significant proportion of beta-structure elements, which were proposed to be localized mostly in the protein regions exposed on the virion outer surface. These beta-structure elements likely formed during virion assembly can comprise the N- and C-terminal protein regions unstructured in the non-virion CP and can mediate inter-subunit interactions. Based on computer-assisted structure modeling, a model for BSMV CP subunit structural fold compliant with the available experimental data was proposed.

Computational Breakthrough of Natural Lead Hits from the Genus of Arisaema against Human Respiratory Syncytial Virus.

Science.gov (United States)

Kant, Kamal; Lal, Uma Ranjan; Ghosh, Manik

2018-01-01

To date, efforts for the prevention and treatment of human respiratory syncytial virus (RSV) infection have been still vain, and there is no safe and effective clinical accepted vaccine. Arisaema genus has claimed for various traditional bioactivities, but scientific assessments are quite limited. This encouraged us to carry out our present study on around 60 phytoconstituents of different Arisaema species as a natural inhibitor against the human RSV. Selected 60 phytochemical entities were evaluated on the docking behavior of human RSV receptor (PDB: 4UCC) using Maestro 9.3 (Schrödinger, LLC, Cambridge, USA). Furthermore, kinetic properties and toxicity nature of top graded ligands were analyzed through QikProp and ProTox tools. Notably, rutin (glide score: -8.49), schaftoside (glide score: -8.18) and apigenin-6,8-di-C-β-D-galactoside (glide score - 7.29) have resulted in hopeful natural lead hits with an ideal range of kinetic descriptors values. ProTox tool (oral rodent toxicity) has resulted in likely toxicity targets of apex-graded tested ligands. Finally, the whole efforts can be explored further as a model to confirm its anti-human RSV potential with wet laboratory experiments. Rutin, schaftoside, and apigenin-6,8-di-C-β-D-galactoside showed promising top hits docking profile against human respiratory syncytial virusMoreover, absorption, distribution, metabolism, excretion properties (QikProp) of top hits resulted within an ideal range of kinetic descriptorsProTox tool highlighted toxicity class ranges, LD 50 values, and possible toxicity targets of apex-graded tested ligands. Abbreviations used: RSV: Respiratory syncytial virus, PRRSV: Porcine respiratory and reproductive syndrome virus, ADME-T: Absorption, distribution, metabolism, excretion, and toxicity.

Recent Perspectives on Genome, Transmission, Clinical Manifestation, Diagnosis, Therapeutic Strategies, Vaccine Developments, and Challenges of Zika Virus Research

Directory of Open Access Journals (Sweden)

Apoorva Shankar

2017-09-01

Full Text Available One of the potential threats to public health microbiology in 21st century is the increased mortality rate caused by Zika virus (ZIKV, a mosquito-borne flavivirus. The severity of ZIKV infection urged World Health Organization (WHO to declare this virus as a global concern. The limited knowledge on the structure, virulent factors, and replication mechanism of the virus posed as hindrance for vaccine development. Several vector and non-vector-borne mode of transmission are observed for spreading the disease. The similarities of the virus with other flaviviruses such as dengue and West Nile virus are worrisome; hence, there is high scope to undertake ZIKV research that probably provide insight for novel therapeutic intervention. Thus, this review focuses on the recent aspect of ZIKV research which includes the outbreak, genome structure, multiplication and propagation of the virus, current animal models, clinical manifestations, available treatment options (probable vaccines and therapeutics, and the recent advancements in computational drug discovery pipelines, challenges and limitation to undertake ZIKV research. The review suggests that the infection due to ZIKV became one of the universal concerns and an interdisciplinary environment of in vitro cellular assays, genomics, proteomics, and computational biology approaches probably contribute insights for screening of novel molecular targets for drug design. The review tried to provide cutting edge knowledge in ZIKV research with future insights required for the development of novel therapeutic remedies to curtail ZIKV infection.

Epstein - Barr Virus

OpenAIRE

Štorkánová, Lenka

2011-01-01

Epstein-Barr virus Bachelor thesis summarizes the findings of Epstein-Barr virus (EBV), its general characteristics, transmission and spread of the virus, symptoms of disease and subsequent therapy and recovery. More specifically, it focuses on infectious mononucleosis, as well as more generally to other diseases, which the Epstein-Barr virus causes. It includes details of the vaccine against EB virus. There are the statistics on the incidence of infectious mononucleosis.

An evolutionary analysis of the Secoviridae family of viruses.

Directory of Open Access Journals (Sweden)

Jeremy R Thompson

Full Text Available The plant-infecting Secoviridae family of viruses forms part of the Picornavirales order, an important group of non-enveloped viruses that infect vertebrates, arthropods, plants and algae. The impact of the secovirids on cultivated crops is significant, infecting a wide range of plants from grapevine to rice. The overwhelming majority are transmitted by ecdysozoan vectors such as nematodes, beetles and aphids. In this study, we have applied a variety of computational methods to examine the evolutionary traits of these viruses. Strong purifying selection pressures were calculated for the coat protein (CP sequences of nine species, although for two species evidence of both codon specific and episodic diversifying selection were found. By using Bayesian phylogenetic reconstruction methods CP nucleotide substitution rates for four species were estimated to range from between 9.29×10(-3 to 2.74×10(-3 (subs/site/year, values which are comparable with the short-term estimates of other related plant- and animal-infecting virus species. From these data, we were able to construct a time-measured phylogeny of the subfamily Comovirinae that estimated divergence of ninety-four extant sequences occurred less than 1,000 years ago with present virus species diversifying between 50 and 250 years ago; a period coinciding with the intensification of agricultural practices in industrial societies. Although recombination (modularity was limited to closely related taxa, significant and often unique similarities in the protein domains between secovirid and animal infecting picorna-like viruses, especially for the protease and coat protein, suggested a shared ancestry. We discuss our results in a wider context and find tentative evidence to indicate that some members of the Secoviridae might have their origins in insects, possibly colonizing plants in a number of founding events that have led to speciation. Such a scenario; virus infection between species of

Emerging influenza viruses and the prospect of a universal influenza virus vaccine.

Science.gov (United States)

Krammer, Florian

2015-05-01

Influenza viruses cause annual seasonal epidemics and pandemics at irregular intervals. Several cases of human infections with avian and swine influenza viruses have been detected recently, warranting enhanced surveillance and the development of more effective countermeasures to address the pandemic potential of these viruses. The most effective countermeasure against influenza virus infection is the use of prophylactic vaccines. However, vaccines that are currently in use for seasonal influenza viruses have to be re-formulated and re-administered in a cumbersome process every year due to the antigenic drift of the virus. Furthermore, current seasonal vaccines are ineffective against novel pandemic strains. This paper reviews zoonotic influenza viruses with pandemic potential and technological advances towards better vaccines that induce broad and long lasting protection from influenza virus infection. Recent efforts have focused on the development of broadly protective/universal influenza virus vaccines that can provide immunity against drifted seasonal influenza virus strains but also against potential pandemic viruses. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Virus-host interaction in feline immunodeficiency virus (FIV) infection.

Science.gov (United States)

Taniwaki, Sueli Akemi; Figueiredo, Andreza Soriano; Araujo, João Pessoa

2013-12-01

Feline immunodeficiency virus (FIV) infection has been the focus of several studies because this virus exhibits genetic and pathogenic characteristics that are similar to those of the human immunodeficiency virus (HIV). FIV causes acquired immunodeficiency syndrome (AIDS) in cats, nevertheless, a large fraction of infected cats remain asymptomatic throughout life despite of persistent chronic infection. This slow disease progression may be due to the presence of factors that are involved in the natural resistance to infection and the immune response that is mounted by the animals, as well as due to the adaptation of the virus to the host. Therefore, the study of virus-host interaction is essential to the understanding of the different patterns of disease course and the virus persistence in the host, and to help with the development of effective vaccines and perhaps the cure of FIV and HIV infections. Copyright © 2013 Elsevier Ltd. All rights reserved.

Systematic analysis of protein identity between Zika virus and other arthropod-borne viruses.

Science.gov (United States)

Chang, Hsiao-Han; Huber, Roland G; Bond, Peter J; Grad, Yonatan H; Camerini, David; Maurer-Stroh, Sebastian; Lipsitch, Marc

2017-07-01

To analyse the proportions of protein identity between Zika virus and dengue, Japanese encephalitis, yellow fever, West Nile and chikungunya viruses as well as polymorphism between different Zika virus strains. We used published protein sequences for the Zika virus and obtained protein sequences for the other viruses from the National Center for Biotechnology Information (NCBI) protein database or the NCBI virus variation resource. We used BLASTP to find regions of identity between viruses. We quantified the identity between the Zika virus and each of the other viruses, as well as within-Zika virus polymorphism for all amino acid k -mers across the proteome, with k ranging from 6 to 100. We assessed accessibility of protein fragments by calculating the solvent accessible surface area for the envelope and nonstructural-1 (NS1) proteins. In total, we identified 294 Zika virus protein fragments with both low proportion of identity with other viruses and low levels of polymorphisms among Zika virus strains. The list includes protein fragments from all Zika virus proteins, except NS3. NS4A has the highest number (190 k -mers) of protein fragments on the list. We provide a candidate list of protein fragments that could be used when developing a sensitive and specific serological test to detect previous Zika virus infections.

Blueberry (Vaccinium corymbosum)-Virus Diseases

Science.gov (United States)

At least six viruses have been found in highbush blueberry plantings in the Pacific Northwest: Blueberry mosaic virus, Blueberry red ringspot virus, Blueberry scorch virus, Blueberry shock virus, Tobacco ringspot virus, and Tomato ringspot virus. Six other virus and virus-like diseases of highbush b...

Ecogenomics and potential biogeochemical impacts of globally abundant ocean viruses

KAUST Repository

Roux, Simon

2016-05-12

Ocean microbes drive biogeochemical cycling on a global scale. However, this cycling is constrained by viruses that affect community composition, metabolic activity, and evolutionary trajectories. Owing to challenges with the sampling and cultivation of viruses, genome-level viral diversity remains poorly described and grossly understudied, with less than 1% of observed surface-ocean viruses known. Here we assemble complete genomes and large genomic fragments from both surface-and deep-ocean viruses sampled during the Tara Oceans and Malaspina research expeditions, and analyse the resulting â global ocean virome\\' dataset to present a global map of abundant, double-stranded DNA viruses complete with genomic and ecological contexts. A total of 15,222 epipelagic and mesopelagic viral populations were identified, comprising 867 viral clusters (defined as approximately genus-level groups). This roughly triples the number of known ocean viral populations and doubles the number of candidate bacterial and archaeal virus genera, providing a near-complete sampling of epipelagic communities at both the population and viral-cluster level. We found that 38 of the 867 viral clusters were locally or globally abundant, together accounting for nearly half of the viral populations in any global ocean virome sample. While two-thirds of these clusters represent newly described viruses lacking any cultivated representative, most could be computationally linked to dominant, ecologically relevant microbial hosts. Moreover, we identified 243 viral-encoded auxiliary metabolic genes, of which only 95 were previously known. Deeper analyses of four of these auxiliary metabolic genes (dsrC, soxYZ, P-II (also known as glnB) and amoC) revealed that abundant viruses may directly manipulate sulfur and nitrogen cycling throughout the epipelagic ocean. This viral catalog and functional analyses provide a necessary foundation for the meaningful integration of viruses into ecosystem models where

Ecogenomics and potential biogeochemical impacts of globally abundant ocean viruses

KAUST Repository

Roux, Simon; Brum, Jennifer R; Dutilh, Bas E.; Sunagawa, Shinichi; Duhaime, Melissa B; Loy, Alexander; Poulos, Bonnie T; Solonenko, Natalie; Lara, Elena; Poulain, Julie; Pesant, Stephane; Kandels-Lewis, Stefanie; Dimier, Celine; Picheral, Marc; Searson, Sarah; Cruaud, Corinne; Alberti, Adriana; Duarte, Carlos M.; Gasol, Josep M M; Vaque, Dolors; Bork, Peer; Acinas, Silvia G; Wincker, Patrick; Sullivan, Matthew B

2016-01-01

Ocean microbes drive biogeochemical cycling on a global scale. However, this cycling is constrained by viruses that affect community composition, metabolic activity, and evolutionary trajectories. Owing to challenges with the sampling and cultivation of viruses, genome-level viral diversity remains poorly described and grossly understudied, with less than 1% of observed surface-ocean viruses known. Here we assemble complete genomes and large genomic fragments from both surface-and deep-ocean viruses sampled during the Tara Oceans and Malaspina research expeditions, and analyse the resulting â global ocean virome' dataset to present a global map of abundant, double-stranded DNA viruses complete with genomic and ecological contexts. A total of 15,222 epipelagic and mesopelagic viral populations were identified, comprising 867 viral clusters (defined as approximately genus-level groups). This roughly triples the number of known ocean viral populations and doubles the number of candidate bacterial and archaeal virus genera, providing a near-complete sampling of epipelagic communities at both the population and viral-cluster level. We found that 38 of the 867 viral clusters were locally or globally abundant, together accounting for nearly half of the viral populations in any global ocean virome sample. While two-thirds of these clusters represent newly described viruses lacking any cultivated representative, most could be computationally linked to dominant, ecologically relevant microbial hosts. Moreover, we identified 243 viral-encoded auxiliary metabolic genes, of which only 95 were previously known. Deeper analyses of four of these auxiliary metabolic genes (dsrC, soxYZ, P-II (also known as glnB) and amoC) revealed that abundant viruses may directly manipulate sulfur and nitrogen cycling throughout the epipelagic ocean. This viral catalog and functional analyses provide a necessary foundation for the meaningful integration of viruses into ecosystem models where they

Single virus genomics: a new tool for virus discovery.

Directory of Open Access Journals (Sweden)

Lisa Zeigler Allen

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

Resistance to Two Heterologous Neurotropic Oncolytic Viruses, Semliki Forest Virus and Vaccinia Virus, in Experimental Glioma

Science.gov (United States)

Le Boeuf, Fabrice; Lemay, Chantal; De Silva, Naomi; Diallo, Jean-Simon; Cox, Julie; Becker, Michelle; Choi, Youngmin; Ananth, Abhirami; Sellers, Clara; Breton, Sophie; Roy, Dominic; Falls, Theresa; Brun, Jan; Hemminki, Akseli; Hinkkanen, Ari; Bell, John C.

2013-01-01

Attenuated Semliki Forest virus (SFV) may be suitable for targeting malignant glioma due to its natural neurotropism, but its replication in brain tumor cells may be restricted by innate antiviral defenses. We attempted to facilitate SFV replication in glioma cells by combining it with vaccinia virus, which is capable of antagonizing such defenses. Surprisingly, we found parenchymal mouse brain tumors to be refractory to both viruses. Also, vaccinia virus appears to be sensitive to SFV-induced antiviral interference. PMID:23221568

Detection of sweet potato virus C, sweet potato virus 2 and sweet potato feathery mottle virus in Portugal.

Science.gov (United States)

Varanda, Carla M R; Santos, Susana J; Oliveira, Mônica D M; Clara, Maria Ivone E; Félix, Maria Rosário F

2015-06-01

Field sweet potato plants showing virus-like symptoms, as stunting, leaf distortion, mosaic and chlorosis, were collected in southwest Portugal and tested for the presence of four potyviruses, sweet potato virus C (SPVC), sweet potato virus 2 (SPV2), sweet potato feathery mottle virus (SPFMV), sweet potato virus G (SPVG), and the crinivirus sweet potato chlorotic stunt virus (SPCSV). DsRNA fractions were extracted from symptomatic leaves and used as templates in single and multiplex RT-PCR assays using previously described specific primers for each analyzed virus. The amplified reaction products for SPVC, SPV2 and SPFMV were of expected size, and direct sequencing of PCR products revealed that they correspond to the coat protein gene (CP) and showed 98%, 99% and 99% identity, respectively, to those viruses. Comparison of the CP genomic and amino acid sequences of the Portuguese viral isolates recovered here with those of ten other sequences of isolates obtained in different countries retrieved from the GenBank showed very few differences. The application of the RT-PCR assays revealed for the first time the presence of SPVC and SPFMV in the sweet potato crop in Portugal, the absence of SPVG and SPCSV in tested plants, as well as the occurrence of triple virus infections under field conditions.

Hepatitis E virus and fulminant hepatitis--a virus or host-specific pathology?

Science.gov (United States)

Smith, Donald B; Simmonds, Peter

2015-04-01

Fulminant hepatitis is a rare outcome of infection with hepatitis E virus. Several recent reports suggest that virus variation is an important determinant of disease progression. To critically examine the evidence that virus-specific factors underlie the development of fulminant hepatitis following hepatitis E virus infection. Published sequence information of hepatitis E virus isolates from patients with and without fulminant hepatitis was collected and analysed using statistical tests to identify associations between virus polymorphisms and disease outcome. Fulminant hepatitis has been reported following infection with all four hepatitis E virus genotypes that infect humans comprising multiple phylogenetic lineages within genotypes 1, 3 and 4. Analysis of virus sequences from individuals infected by a common source did not detect any common substitutions associated with progression to fulminant hepatitis. Re-analysis of previously reported associations between virus substitutions and fulminant hepatitis suggests that these were probably the result of sampling biases. Host-specific factors rather than virus genotype, variants or specific substitutions appear to be responsible for the development of fulminant hepatitis. © 2014 The Authors. Liver International Published by John Wiley & Sons Ltd.

Circulating avian influenza viruses closely related to the 1918 virus have pandemic potential

Science.gov (United States)

Watanabe, Tokiko; Zhong, Gongxun; Russell, Colin A.; Nakajima, Noriko; Hatta, Masato; Hanson, Anthony; McBride, Ryan; Burke, David F.; Takahashi, Kenta; Fukuyama, Satoshi; Tomita, Yuriko; Maher, Eileen A.; Watanabe, Shinji; Imai, Masaki; Neumann, Gabriele; Hasegawa, Hideki; Paulson, James C.; Smith, Derek J.; Kawaoka, Yoshihiro

2014-01-01

Summary Wild birds harbor a large gene pool of influenza A viruses that have the potential to cause influenza pandemics. Foreseeing and understanding this potential is important for effective surveillance. Our phylogenetic and geographic analyses revealed the global prevalence of avian influenza virus genes whose proteins differ only a few amino acids from the 1918 pandemic influenza virus, suggesting that 1918-like pandemic viruses may emerge in the future. To assess this risk, we generated and characterized a virus composed of avian influenza viral segments with high homology to the 1918 virus. This virus exhibited higher pathogenicity in mice and ferrets than an authentic avian influenza virus. Further, acquisition of seven amino acid substitutions in the viral polymerases and the hemagglutinin surface glycoprotein conferred respiratory droplet transmission to the 1918-like avian virus in ferrets, demonstrating that contemporary avian influenza viruses with 1918 virus-like proteins may have pandemic potential. PMID:24922572

Lack of Durable Cross-Neutralizing Antibodies Against Zika Virus from Dengue Virus Infection.

Science.gov (United States)

Collins, Matthew H; McGowan, Eileen; Jadi, Ramesh; Young, Ellen; Lopez, Cesar A; Baric, Ralph S; Lazear, Helen M; de Silva, Aravinda M

2017-05-01

Cross-reactive antibodies elicited by dengue virus (DENV) infection might affect Zika virus infection and confound serologic tests. Recent data demonstrate neutralization of Zika virus by monoclonal antibodies or human serum collected early after DENV infection. Whether this finding is true in late DENV convalescence (>6 months after infection) is unknown. We studied late convalescent serum samples from persons with prior DENV or Zika virus exposure. Despite extensive cross-reactivity in IgG binding, Zika virus neutralization was not observed among primary DENV infections. We observed low-frequency (23%) Zika virus cross-neutralization in repeat DENV infections. DENV-immune persons who had Zika virus as a secondary infection had distinct populations of antibodies that neutralized DENVs and Zika virus, as shown by DENV-reactive antibody depletion experiments. These data suggest that most DENV infections do not induce durable, high-level Zika virus cross-neutralizing antibodies. Zika virus-specific antibody populations develop after Zika virus infection irrespective of prior DENV immunity.

Simple genomes, complex interactions: Epistasis in RNA virus

Science.gov (United States)

Elena, Santiago F.; Solé, Ricard V.; Sardanyés, Josep

2010-06-01

Owed to their reduced size and low number of proteins encoded, RNA viruses and other subviral pathogens are often considered as being genetically too simple. However, this structural simplicity also creates the necessity for viral RNA sequences to encode for more than one protein and for proteins to carry out multiple functions, all together resulting in complex patterns of genetic interactions. In this work we will first review the experimental studies revealing that the architecture of viral genomes is dominated by antagonistic interactions among loci. Second, we will also review mathematical models and provide a description of computational tools for the study of RNA virus dynamics and evolution. As an application of these tools, we will finish this review article by analyzing a stochastic bit-string model of in silico virus replication. This model analyzes the interplay between epistasis and the mode of replication on determining the population load of deleterious mutations. The model suggests that, for a given mutation rate, the deleterious mutational load is always larger when epistasis is predominantly antagonistic than when synergism is the rule. However, the magnitude of this effect is larger if replication occurs geometrically than if it proceeds linearly.

Ganjam virus.

Science.gov (United States)

Sudeep, A B; Jadi, R S; Mishra, A C

2009-11-01

Ganjam virus (GANV), a member of genus Nairovirus of family Bunyavirdae is of considerable veterinary importance in India. Though, predominantly tick borne, GANV was also isolated from mosquitoes, man and sheep. Neutralizing and complement fixing antibodies to GANV have been detected in animal and human sera collected from different parts of the country. Thirty three strains of GANV have been isolated from India, mainly from Haemaphysalis ticks. The virus replicated in certain vertebrate and mosquito cell lines and found pathogenic to laboratory animals. One natural infection and five laboratory-acquired infections in men were also reported. GANV is antigenically related to Nairobi sheep disease virus (NSDV) of Africa, which is highly pathogenic for sheep and goats causing 70-90 per cent mortality among the susceptible population. Recent molecular studies have demonstrated that GANV is an Asian variant of NSDV and both these viruses are related to the dreaded Crimean Congo haemorrhagic fever (CCHF) group viruses. The versatility of the virus to replicate in different arthropod species, its ability to infect sheep, goat and man makes it an important zoonotic agent.

Physician use of updated anti-virus software in a tertiary Nigerian hospital.

Science.gov (United States)

Laabes, E P; Nyango, D D; Ayedima, M M; Ladep, N G

2010-01-01

While physicians are becoming increasingly dependent on computers and the internet, highly lethal malware continue to be loaded into cyberspace. We sought to assess the proportion of physicians with updated anti-virus software in Jos University Teaching Hospital Nigeria and to determine perceived barriers to getting updates. We used a pre-tested semi-structured self-administered questionnaire to conduct a cross-sectional survey among 118 physicians. The mean age (+/- SD) of subjects was 34 (+/- 4) years, with 94 male and 24 female physicians. Forty-two (36.5%) of 115 physicians with anti-virus software used an updated program (95% Cl: 27, 45). The top-three antivirus software were: McAfee 40 (33.9%), AVG 37 (31.4%) and Norton 17 (14.4%). Common infections were: Trojan horse 22 (29.7%), Brontok worm 8 (10.8%), and Ravmonlog.exe 5 (6.8%). Internet browsing with a firewall was an independent determinant for use of updated anti-virus software [OR 4.3, 95% CI, 1.86, 10.02; P malware producers and anti-virus software developers.

The Drosophila Nora virus is an enteric virus, transmitted via feces.

Science.gov (United States)

Habayeb, Mazen S; Cantera, Rafael; Casanova, Gabriela; Ekström, Jens-Ola; Albright, Shannon; Hultmark, Dan

2009-04-01

The biology of the Drosophila viruses has not been intensely investigated. Here we have investigated the biology of the Nora virus, a persistent Drosophila virus. We find that injected Nora virus is able to replicate in the files, reaching a high titer that is maintained in the next generation. There is a remarkable variation in the viral loads of individual flies in persistently infected stocks; the titers can differ by three orders of magnitude. The Nora virus is mainly found in the intestine of infected flies, and the histology of these infected intestines show increased vacuolization. The virus is excreted in the feces and is horizontally transmitted. The Nora virus infection has a very mild effect on the longevity of the flies, and no significant effect on the number of eggs laid and the percent of eggs that develop to adults.

Herpes viruses and human papilloma virus in nasal polyposis and controls

Directory of Open Access Journals (Sweden)

Dimitrios Ioannidis

2015-12-01

Full Text Available ABSTRACT INTRODUCTION: Chronic rhinosinusitis with nasal polyps is a multifactorial disease entity with an unclear pathogenesis. Contradictory data exist in the literature on the potential implication of viral elements in adult patients with chronic rhinosinusitis. OBJECTIVE: To compare the prevalence of human herpes viruses (1-6 and Human Papilloma Virus in adult patients with chronic rhinosinusitis with nasal polyps and healthy controls. METHODS: Viral DNA presence was evaluated by real-time polymerase chain reaction application to nasal polyps specimens from 91 chronic rhinosinusitis with nasal polyps patients and nasal turbinate mucosa from 38 healthy controls. RESULTS: Epstein-Barr virus positivity was higher in nasal polyps (24/91; 26.4% versus controls (4/38; 10.5%, but the difference did not reach significance (p = 0.06. Human herpes virus-6 positivity was lower in nasal polyps (13/91; 14.29% versus controls (10/38; 26.32%,p = 0.13. In chronic rhinosinusitis with nasal polyps group, 1 sample was herpes simplex virus-1-positive (1/91; 1.1%, and another was cytomegalovirus-positive (1/91; 1.1%, versus none in controls. No sample was positive for herpes simplex virus-2, varicella-zoster virus, high-risk-human papilloma viruses (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and low-risk-human papilloma viruses (6, 11. CONCLUSION: Differences in Epstein-Barr virus and human herpes virus-6 positivity among patients with chronic rhinosinusitis with nasal polyps and healthy controls are not statistically significant, weakening the likelihood of their implication in chronic rhinosinusitis with nasal polyps pathogenesis.

Evaluation of recombinant influenza virus-simian immunodeficiency virus vaccines in macaques.

Science.gov (United States)

Sexton, Amy; De Rose, Robert; Reece, Jeanette C; Alcantara, Sheilajen; Loh, Liyen; Moffat, Jessica M; Laurie, Karen; Hurt, Aeron; Doherty, Peter C; Turner, Stephen J; Kent, Stephen J; Stambas, John

2009-08-01

There is an urgent need for human immunodeficiency virus (HIV) vaccines that induce robust mucosal immunity. Influenza A viruses (both H1N1 and H3N2) were engineered to express simian immunodeficiency virus (SIV) CD8 T-cell epitopes and evaluated following administration to the respiratory tracts of 11 pigtail macaques. Influenza virus was readily detected from respiratory tract secretions, although the infections were asymptomatic. Animals seroconverted to influenza virus and generated CD8 and CD4 T-cell responses to influenza virus proteins. SIV-specific CD8 T-cell responses bearing the mucosal homing marker beta7 integrin were induced by vaccination of naïve animals. Further, SIV-specific CD8 T-cell responses could be boosted by recombinant influenza virus-SIV vaccination of animals with already-established SIV infection. Sequential vaccination with influenza virus-SIV recombinants of different subtypes (H1N1 followed by H3N2 or vice versa) produced only a limited boost in immunity, probably reflecting T-cell immunity to conserved internal proteins of influenza A virus. SIV challenge of macaques vaccinated with an influenza virus expressing a single SIV CD8 T cell resulted in a large anamnestic recall CD8 T-cell response, but immune escape rapidly ensued and there was no impact on chronic SIV viremia. Although our results suggest that influenza virus-HIV vaccines hold promise for the induction of mucosal immunity to HIV, broader antigen cover will be needed to limit cytotoxic T-lymphocyte escape.

Schmallenberg virus – et nyt virus hos drøvtyggere

DEFF Research Database (Denmark)

Lohse, Louise

undersøgelser på laboratoriet, blev alle prøver i en længere periode testet negative for kendte patogener, der evt. kunne tænkes at knytte sig til disse sygdomsudbrud. Efterfølgende fandt man ved sekvensanalyse på DNA/RNA oprenset fra prøvematerialet lighed med virus fra orthobunyavirusgruppen. Disse virus er...... normalt vektorbårne og er kendt som årsag til sygdom i drøvtyggere i Australien, Asien, Afrika og Mellemøsten. Det nye virus blev kaldt Schmallenberg virus (SBV) efter stedet hvor det første tilfælde blev påvist. Siden har Schmallenberg virus spredt sig og er nu påvist i får, kvæg og geder i Tyskland......, Holland, Belgien, Luxembourg, Frankrig, Spanien, Italien og Storbritannien (status april 2012). Det antages, at virus overføres med mitter og myg og inkubationstiden har fra eksperimentelle forsøg vist sig at være kort (1-4 dage). Virus cirkulerer få dage i blodet og manifesterer sig ved milde uspecifikke...

Protein sequences clustering of herpes virus by using Tribe Markov clustering (Tribe-MCL)

Science.gov (United States)

Bustamam, A.; Siswantining, T.; Febriyani, N. L.; Novitasari, I. D.; Cahyaningrum, R. D.

2017-07-01

The herpes virus can be found anywhere and one of the important characteristics is its ability to cause acute and chronic infection at certain times so as a result of the infection allows severe complications occurred. The herpes virus is composed of DNA containing protein and wrapped by glycoproteins. In this work, the Herpes viruses family is classified and analyzed by clustering their protein-sequence using Tribe Markov Clustering (Tribe-MCL) algorithm. Tribe-MCL is an efficient clustering method based on the theory of Markov chains, to classify protein families from protein sequences using pre-computed sequence similarity information. We implement the Tribe-MCL algorithm using an open source program of R. We select 24 protein sequences of Herpes virus obtained from NCBI database. The dataset consists of three types of glycoprotein B, F, and H. Each type has eight herpes virus that infected humans. Based on our simulation using different inflation factor r=1.5, 2, 3 we find a various number of the clusters results. The greater the inflation factor the greater the number of their clusters. Each protein will grouped together in the same type of protein.

Sensitive radioimmunosorbent assay for the detection of plant viruses. [Cauliflower mosaic virus, lettuce mosaic virus

Energy Technology Data Exchange (ETDEWEB)

Ghabrial, S A; Shepherd, R J [Kentucky Univ., Lexington (USA); California Univ., Davis (USA))

1980-06-01

A simple and highly sensitive radioimmunosorbent assay (RISA) for the detection of plant viruses is described. The RISA procedure is a microplate method based on the principle of 'double-antibody sandwich' and follows essentially the protocol of the enzyme-linked immunosorbent assay (ELISA) (Clark and Adams, 1977), with the exception that /sup 125/I-labelled ..gamma..-globulin is substituted for the ..gamma..-globulin enzyme conjugate; the bound /sup 125/I-..gamma..-globulin is dissociated by acidification from the double-antibody sandwich. The radioactivity is proportional to virus concentration, and cauliflower mosaic virus (CaMV) and lettuce mosaic virus (LMV) could be detected at concentrations as low as 5 and 2 ng/ml, respectively. Direct evidence of the adverse effects of conjugation with enzyme on the binding abilities of antibodies is presented. The RISA procedure should prove valuable with viruses for which the ELISA values are too low to be dependable.

Release of Virus from Lymphoid Tissue Affects Human Immunodeficiency Virus Type 1 and Hepatitis C Virus Kinetics in the Blood

NARCIS (Netherlands)

Müller, Viktor; Marée, Athanasius F.M.; Boer, R.J. de

2000-01-01

Kinetic parameters of human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) infections have been estimated from plasma virus levels following perturbation of the chronically infected (quasi-) steady state. We extend previous models by also considering the large pool of virus

Hepatitis E Virus and Related Viruses in Animals.

Science.gov (United States)

Thiry, D; Mauroy, A; Pavio, N; Purdy, M A; Rose, N; Thiry, E; de Oliveira-Filho, E F

2017-02-01

Hepatitis E is an acute human liver disease in healthy individuals which may eventually become chronic. It is caused by the hepatitis E virus (HEV) and can have a zoonotic origin. Nearly 57,000 people die yearly from hepatitis E-related conditions. The disease is endemic in both developing and developed countries with distinct epidemiologic profiles. In developing countries, the disease is associated with inadequate water treatment, while in developed countries, transmission is associated with animal contact and the ingestion of raw or uncooked meat, especially liver. All human HEV are grouped into at least four genotypes, while HEV or HEV-related viruses have been identified in an increasing number of domestic and wild animal species. Despite a high genetic diversity, only one single HEV serotype has been described to date for HEV genotypes 1-4. The discovery of new HEV or HEV-related viruses leads to a continuing increase in the number of genotypes. In addition, the genome organization of all these viruses is variable with overlapping open reading frames (ORF) and differences in the location of ORF3. In spite of the role of some domestic and wild animals as reservoir, the origin of HEV and HEV-related viruses in humans and animals is still unclear. This review discusses aspects of the detection, molecular virology, zoonotic transmission and origin of HEV and HEV-related viruses in the context of 'One Health' and establishes a link between the previous and the new taxonomy of this growing virus family. © 2015 Blackwell Verlag GmbH.

"The evil virus cell": Students' knowledge and beliefs about viruses.

Science.gov (United States)

Simon, Uwe K; Enzinger, Sonja M; Fink, Andreas

2017-01-01

Education about virus biology at school is of pivotal interest to raise public awareness concerning means of disease transmission and, thus, methods to prevent infection, and to reduce unnecessary antibiotic treatment due to patient pressure on physicians in case of viral diseases such as influenza. This study aimed at making visible the knowledge of Austrian high school and university students with respect to virus biology, virus structure and health-education issues. The data presented here stem from comprehensive questionnaire analyses, including the task to draw a virus, from a cross-sectional study with 133 grade 7 and 199 grade 10 high school students, and 133 first-year biology and 181 first-year non-biology university students. Analyses were performed both quantitatively and qualitatively. ANOVA revealed a highly significant group effect for total knowledge relating to virus biology and health issues (F(3, 642) = 44.17, p students and grade 10 high school students. Students enrolled in university-level biology outperformed all other groups, even though they had not yet encountered this topic at their courses; part of this phenomenon might be due to their affinity for learning about biological topics. However, even many first-year biology students had a high number of severe misconceptions, e.g., defining a virus as a pro- or eukaryotic cell, or falsely naming malaria as a viral disease. Since there was no significant difference in virus-related knowledge between high schools, virus biology seems to have been taught similarly among the tested schools. However, the majority of participants stated that the virus-related knowledge they had acquired at school was not sufficient. Based on the results presented here we urgently suggest improving and intensifying teaching this topic at school, since virus-related knowledge was by far too fragmentary among many participants. Such lack of health-relevant knowledge may contribute to pressure on physicians by patients

Herpes viruses and human papilloma virus in nasal polyposis and controls.

Science.gov (United States)

Ioannidis, Dimitrios; Lachanas, Vasileios A; Florou, Zoe; Bizakis, John G; Petinaki, Efthymia; Skoulakis, Charalampos E

2015-01-01

Chronic rhinosinusitis with nasal polyps is a multifactorial disease entity with an unclear pathogenesis. Contradictory data exist in the literature on the potential implication of viral elements in adult patients with chronic rhinosinusitis. To compare the prevalence of human herpes viruses (1-6) and Human Papilloma Virus in adult patients with chronic rhinosinusitis with nasal polyps and healthy controls. Viral DNA presence was evaluated by real-time polymerase chain reaction application to nasal polyps specimens from 91 chronic rhinosinusitis with nasal polyps patients and nasal turbinate mucosa from 38 healthy controls. Epstein-Barr virus positivity was higher in nasal polyps (24/91; 26.4%) versus controls (4/38; 10.5%), but the difference did not reach significance (p=0.06). Human herpes virus-6 positivity was lower in nasal polyps (13/91; 14.29%) versus controls (10/38; 26.32%, p=0.13). In chronic rhinosinusitis with nasal polyps group, 1 sample was herpes simplex virus-1-positive (1/91; 1.1%), and another was cytomegalovirus-positive (1/91; 1.1%), versus none in controls. No sample was positive for herpes simplex virus-2, varicella-zoster virus, high-risk-human papilloma viruses (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59) and low-risk-human papilloma viruses (6, 11). Differences in Epstein-Barr virus and human herpes virus-6 positivity among patients with chronic rhinosinusitis with nasal polyps and healthy controls are not statistically significant, weakening the likelihood of their implication in chronic rhinosinusitis with nasal polyps pathogenesis. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Stochastic modeling of virus capsid assembly pathways

Science.gov (United States)

Schwartz, Russell

2009-03-01

Virus capsids have become a key model system for understanding self-assembly due to their high complexity, robust and efficient assembly processes, and experimental tractability. Our ability to directly examine and manipulate capsid assembly kinetics in detail nonetheless remains limited, creating a need for computer models that can infer experimentally inaccessible features of the assembly process and explore the effects of hypothetical manipulations on assembly trajectories. We have developed novel algorithms for stochastic simulation of capsid assembly [1,2] that allow us to model capsid assembly over broad parameter spaces [3]. We apply these methods to study the nature of assembly pathway control in virus capsids as well as their sensitivity to assembly conditions and possible experimental interventions. [4pt] [1] F. Jamalyaria, R. Rohlfs, and R. Schwartz. J Comp Phys 204, 100 (2005). [0pt] [2] N. Misra and R. Schwartz. J Chem Phys 129, in press (2008). [0pt] [3] B. Sweeney, T. Zhang, and R. Schwartz. Biophys J 94, 772 (2008).

Identification of bioflavonoid as fusion inhibitor of dengue virus using molecular docking approach

Directory of Open Access Journals (Sweden)

Asif Mir

Full Text Available Dengue virus with four distinct serotypes belongs to Flavivirus, poses a significant threat to human health and becomes an emerging global problem. Membrane fusion is a central molecular event during viral entry into host cell. To prevent viral infection it is necessary to interrupt the virus replication at an early stage of attachment. Dengue Virus (DENV envelope protein experiences conformational changes and it causes the virus to fuse with host cell. Hinge region movement of domain I and II in envelope protein facilitates the fusion process. Small molecules that bind in this pocket may have the ability to interrupt the conformational changes that trigger fusion process. We chose different flavonoids (baicalein, fisetin, hesperetin, naringenin/ naringin, quercetin and rutin that possess anti dengue activity. Molecular docking analysis was done to examine the inhibitory effect of flavonoids against envelope protein of DENV-2. Results manifest quercetin (flavonoid found in Carica papaya, apple and even in lemon as the only flavone that can interrupt the fusion process of virus by inhibiting the hinge region movement and by blocking the conformational rearrangement in envelope protein. These novel findings using computational approach are worthwhile and will be a bridge to check the efficacy of compounds using appropriate animal model under In vivo studies. This information can be used by new techniques and provides a way to control dengue virus infection. Keywords: Dengue virus, Inhibitor identification, Molecular docking, Interaction analysis

Viruses in reptiles

Directory of Open Access Journals (Sweden)

Ariel Ellen

2011-09-01

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

Genomic characterisation of Almpiwar virus, Harrison Dam virus and Walkabout Creek virus; three novel rhabdoviruses from northern Australia

Directory of Open Access Journals (Sweden)

Jane McAllister

2014-09-01

Full Text Available Rhabdoviridae represent a diverse group of viruses with the potential to cause disease in humans, animals and plants. Currently there are nine genera in the family; however a large number of rhabdoviruses remain unassigned. Here we characterise three novel rhabdoviruses genomes. Almpiwar virus (ALMV, isolated from skinks in northern Queensland, is the first completely sequenced rhabdovirus from squamates, with serological studies indicating multiple animal host species. Harrison Dam virus (HARDV and Walkabout Creek virus (WACV were isolated from mosquitoes in the Northern Territory and biting midges in southern Queensland respectively and their vertebrate hosts remain unknown. Serological cross-neutralisation tests with other Australian rhabdoviruses indicate that ALMV, WACV and HARDV are distinct viruses with little antigenic cross-reactivity. Next-generation sequencing revealed that all viruses encode the core proteins common to rhabdoviruses (N, P, M, G and L, plus additional ORFs between the M and G genes. HARDV also contains a small ORF between the G and L genes. Phylogenetic analysis of N and L proteins suggests that HARDV and WACV share a common lineage with the tupaviruses and Sandjimba group, whereas ALMV is a distinct and divergent virus showing no clear relationship to any rhabdovirus except the recently characterised Niahka virus (NIAV.

Deterministic and Stochastic Study for an Infected Computer Network Model Powered by a System of Antivirus Programs

Directory of Open Access Journals (Sweden)

Youness El Ansari

2017-01-01

Full Text Available We investigate the various conditions that control the extinction and stability of a nonlinear mathematical spread model with stochastic perturbations. This model describes the spread of viruses into an infected computer network which is powered by a system of antivirus software. The system is analyzed by using the stability theory of stochastic differential equations and the computer simulations. First, we study the global stability of the virus-free equilibrium state and the virus-epidemic equilibrium state. Furthermore, we use the Itô formula and some other theoretical theorems of stochastic differential equation to discuss the extinction and the stationary distribution of our system. The analysis gives a sufficient condition for the infection to be extinct (i.e., the number of viruses tends exponentially to zero. The ergodicity of the solution and the stationary distribution can be obtained if the basic reproduction number Rp is bigger than 1, and the intensities of stochastic fluctuations are small enough. Numerical simulations are carried out to illustrate the theoretical results.

Powassan (POW) Virus Basics

Science.gov (United States)

... Health Professionals Related Topics For International Travelers Powassan Virus Disease Basics Download this fact sheet formatted for ... Virus Disease Fact Sheet (PDF) What is Powassan virus? Powassan virus is a tickborne flavivirus that is ...

Initial characterization of Vaccinia Virus B4 suggests a role in virus spread

Energy Technology Data Exchange (ETDEWEB)

Burles, Kristin; Irwin, Chad R.; Burton, Robyn-Lee [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada); Schriewer, Jill [Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, MO (United States); Evans, David H. [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada); Buller, R. Mark [Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, MO (United States); Barry, Michele, E-mail: michele.barry@ualberta.ca [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada)

2014-05-15

Currently, little is known about the ankyrin/F-box protein B4. Here, we report that B4R-null viruses exhibited reduced plaque size in tissue culture, and decreased ability to spread, as assessed by multiple-step growth analysis. Electron microscopy indicated that B4R-null viruses still formed mature and extracellular virions; however, there was a slight decrease of virions released into the media following deletion of B4R. Deletion of B4R did not affect the ability of the virus to rearrange actin; however, VACV811, a large vaccinia virus deletion mutant missing 55 open reading frames, had decreased ability to produce actin tails. Using ectromelia virus, a natural mouse pathogen, we demonstrated that virus devoid of EVM154, the B4R homolog, showed decreased spread to organs and was attenuated during infection. This initial characterization suggests that B4 may play a role in virus spread, and that other unidentified mediators of actin tail formation may exist in vaccinia virus. - Highlights: • B4R-null viruses show reduced plaque size, and decreased ability to spread. • B4R-null viruses formed mature and extracellular virions; and rearranged actin. • Virus devoid of EVM154, the B4R homolog, was attenuated during infection. • Initial characterization suggests that B4 may play a role in virus spread. • Unidentified mediators of actin tail formation may exist in vaccinia virus.

Initial characterization of Vaccinia Virus B4 suggests a role in virus spread

International Nuclear Information System (INIS)

Burles, Kristin; Irwin, Chad R.; Burton, Robyn-Lee; Schriewer, Jill; Evans, David H.; Buller, R. Mark; Barry, Michele

2014-01-01

Currently, little is known about the ankyrin/F-box protein B4. Here, we report that B4R-null viruses exhibited reduced plaque size in tissue culture, and decreased ability to spread, as assessed by multiple-step growth analysis. Electron microscopy indicated that B4R-null viruses still formed mature and extracellular virions; however, there was a slight decrease of virions released into the media following deletion of B4R. Deletion of B4R did not affect the ability of the virus to rearrange actin; however, VACV811, a large vaccinia virus deletion mutant missing 55 open reading frames, had decreased ability to produce actin tails. Using ectromelia virus, a natural mouse pathogen, we demonstrated that virus devoid of EVM154, the B4R homolog, showed decreased spread to organs and was attenuated during infection. This initial characterization suggests that B4 may play a role in virus spread, and that other unidentified mediators of actin tail formation may exist in vaccinia virus. - Highlights: • B4R-null viruses show reduced plaque size, and decreased ability to spread. • B4R-null viruses formed mature and extracellular virions; and rearranged actin. • Virus devoid of EVM154, the B4R homolog, was attenuated during infection. • Initial characterization suggests that B4 may play a role in virus spread. • Unidentified mediators of actin tail formation may exist in vaccinia virus

How Hepatitis D Virus Can Hinder the Control of Hepatitis B Virus

NARCIS (Netherlands)

Xiridiou, M.; Borkent-Raven, B.; Hulshof, J.; Wallinga, J.

2009-01-01

Background: Hepatitis D (or hepatitis delta) virus is a defective virus that relies on hepatitis B virus (HBV) for transmission; infection with hepatitis D can occur only as coinfection with HBV or superinfection of an existing HBV infection. Because of the bond between the two viruses, control

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 STANDARD...

Influenza (Flu) Viruses

Science.gov (United States)

... Types Seasonal Avian Swine Variant Pandemic Other Influenza (Flu) Viruses Language: English (US) Español Recommend on Facebook ... influenza circulate and cause illness. More Information about Flu Viruses Types of Influenza Viruses Influenza A and ...

[The growth of attenuated strains of canine parvovirus, mink enteritis virus, feline panleukopenia virus, and rabies virus on various types of cell cultures].

Science.gov (United States)

Zuffa, T

1987-10-01

The growth characteristics were studied in the attenuated strains of canine parvovirus CPVA-BN 80/82, mink enteritis virus MEVA-BN 63/82 and feline panleucopenia virus FPVA-BN 110/83 on the stable feline kidney cell line FE, and in the attenuated canine distemper virus CDV-F-BN 10/83 on chicken embryo cell cultures (KEB) and cultures of the stable cell line VERO. When the FE cultures were infected with different parvoviruses in cell suspension at MOI 2-4 TKID50 per cell, the first multiplication of the intracellular virus was recorded 20 hours p. i. In the canine parvovirus, the content of intracellular and extracellular virus continued increasing parallelly until the fourth day; then, from the fourth to the sixth day, the content of extracellular virus still increased whereas that of intracellular virus fell rapidly. In the case of the mink enteritis virus the release of the virus into the culture medium continued parallelly with the production of the cellular virus until the sixth day. In the case of the feline panleucopenia virus the values concerning free virus and virus bound to cells were lower, starting from the second day p. i. When KEB or VERO cultures were infected in cell suspension with the canine distemper virus at MOI about 0.004 per 1 cell, the replicated intracellular virus was first recorded in the KEB cultures five hours after infection but in the VERO cultures only 20 hours after infection, with a timely release of the virus into the culture medium in both kinds of tissue. In the KEB and VERO cultures the highest values of infection titres were recorded on the fourth day p. i., the course of virus multiplication on the cells being parallel with its release into the culture medium.

Central Nervous System Effects of Intrauterine Zika Virus Infection: A Pictorial Review.

Science.gov (United States)

Ribeiro, Bianca Guedes; Werner, Heron; Lopes, Flávia P P L; Hygino da Cruz, L Celso; Fazecas, Tatiana M; Daltro, Pedro A N; Nogueira, Renata A

2017-10-01

Relatively few agents have been associated with congenital infections involving the brain. One such agent is the Zika virus, which has caused several outbreaks worldwide and has spread in the Americas since 2015. The Zika virus is an arbovirus transmitted by infected female mosquito vectors, such as the Aedes aegypti mosquito. This virus has been commonly associated with congenital infections of the central nervous system and has greatly increased the rates of microcephaly. Ultrasonography (US) remains the method of choice for fetal evaluation of congenital Zika virus infection. For improved assessment of the extent of the lesions, US should be complemented by magnetic resonance (MR) imaging. Postnatal computed tomography and MR imaging can also unveil additional findings of central nervous system involvement, such as microcephaly with malformation of cortical development, ventriculomegaly, and multifocal calcifications in the cortical-subcortical junction, along with associated cortical atrophy. The calcifications may be punctate, dystrophic, linear, or coarse and may follow a predominantly bandlike distribution. A small anterior fontanelle with prematurely closed sutures is also observed with Zika virus infection. In this review, the prenatal and postnatal neurologic imaging findings of congenital Zika virus infection are covered. Radiologists must be aware of this challenging entity and have knowledge of the various patterns that may be depicted with each imaging modality and the main differential diagnosis of the disease. As in other neurologic infections, serial imaging is able to help demonstrate the progression of the findings. © RSNA, 2017.

Viruses of asparagus.

Science.gov (United States)

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

2012-01-01

The current knowledge on viruses infecting asparagus (Asparagus officinalis) is reviewed. Over half a century, nine virus species belonging to the genera Ilarvirus, Cucumovirus, Nepovirus, Tobamovirus, Potexvirus, and Potyvirus have been found in this crop. The potyvirus Asparagus virus 1 (AV1) and the ilarvirus Asparagus virus 2 (AV2) are widespread and negatively affect the economic life of asparagus crops reducing yield and increasing the susceptibility to biotic and abiotic stress. The main properties and epidemiology of AV1 and AV2 as well as diagnostic techniques for their detection and identification are described. Minor viruses and control are briefly outlined. Copyright © 2012 Elsevier Inc. All rights reserved.

Viruses and Breast Cancer

Science.gov (United States)

Lawson, James S.; Heng, Benjamin

2010-01-01

Viruses are the accepted cause of many important cancers including cancers of the cervix and anogenital area, the liver, some lymphomas, head and neck cancers and indirectly human immunodeficiency virus associated cancers. For over 50 years, there have been serious attempts to identify viruses which may have a role in breast cancer. Despite these efforts, the establishment of conclusive evidence for such a role has been elusive. However, the development of extremely sophisticated new experimental techniques has allowed the recent development of evidence that human papilloma virus, Epstein-Barr virus, mouse mammary tumor virus and bovine leukemia virus may each have a role in the causation of human breast cancers. This is potentially good news as effective vaccines are already available to prevent infections from carcinogenic strains of human papilloma virus, which causes cancer of the uterine cervix. PMID:24281093

Viruses and Breast Cancer

International Nuclear Information System (INIS)

Lawson, James S.; Heng, Benjamin

2010-01-01

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

Viruses and Breast Cancer

Energy Technology Data Exchange (ETDEWEB)

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

2010-04-30

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

"The evil virus cell": Students‘ knowledge and beliefs about viruses

Science.gov (United States)

Enzinger, Sonja M.; Fink, Andreas

2017-01-01

Education about virus biology at school is of pivotal interest to raise public awareness concerning means of disease transmission and, thus, methods to prevent infection, and to reduce unnecessary antibiotic treatment due to patient pressure on physicians in case of viral diseases such as influenza. This study aimed at making visible the knowledge of Austrian high school and university students with respect to virus biology, virus structure and health-education issues. The data presented here stem from comprehensive questionnaire analyses, including the task to draw a virus, from a cross-sectional study with 133 grade 7 and 199 grade 10 high school students, and 133 first-year biology and 181 first-year non-biology university students. Analyses were performed both quantitatively and qualitatively. ANOVA revealed a highly significant group effect for total knowledge relating to virus biology and health issues (F(3, 642) = 44.17, p students and grade 10 high school students. Students enrolled in university-level biology outperformed all other groups, even though they had not yet encountered this topic at their courses; part of this phenomenon might be due to their affinity for learning about biological topics. However, even many first-year biology students had a high number of severe misconceptions, e.g., defining a virus as a pro- or eukaryotic cell, or falsely naming malaria as a viral disease. Since there was no significant difference in virus-related knowledge between high schools, virus biology seems to have been taught similarly among the tested schools. However, the majority of participants stated that the virus-related knowledge they had acquired at school was not sufficient. Based on the results presented here we urgently suggest improving and intensifying teaching this topic at school, since virus-related knowledge was by far too fragmentary among many participants. Such lack of health-relevant knowledge may contribute to pressure on physicians by patients

The 3' untranslated region of tobacco necrosis virus RNA contains a barley yellow dwarf virus-like cap-independent translation element.

Science.gov (United States)

Shen, Ruizhong; Miller, W Allen

2004-05-01

RNAs of many viruses are translated efficiently in the absence of a 5' cap structure. The tobacco necrosis virus (TNV) genome is an uncapped, nonpolyadenylated RNA whose translation mechanism has not been well investigated. Computational analysis predicted a cap-independent translation element (TE) within the 3' untranslated region (3' UTR) of TNV RNA that resembles the TE of barley yellow dwarf virus (BYDV), a luteovirus. Here we report that such a TE does indeed exist in the 3' UTR of TNV strain D. Like the BYDV TE, the TNV TE (i) functions both in vitro and in vivo, (ii) requires additional sequence for cap-independent translation in vivo, (iii) has a similar secondary structure and the conserved sequence CGGAUCCUGGGAAACAGG, (iv) is inactivated by a four-base duplication in this conserved sequence, (v) can function in the 5' UTR, and (vi) when located in its natural 3' location, may form long-distance base pairing with the viral 5' UTR that is conserved and probably required. The TNV TE differs from the BYDV TE by having only three helical domains instead of four. Similar structures were found in all members of the Necrovirus genus of the Tombusviridae family, except satellite tobacco necrosis virus, which harbors a different 3' cap-independent translation domain. The presence of the BYDV-like TE in select genera of different families indicates that phylogenetic distribution of TEs does not follow standard viral taxonomic relationships. We propose a new class of cap-independent TE called BYDV-like TE.

Influenza virus inactivated by artificial ribonucleases as a prospective killed virus vaccine.

Science.gov (United States)

Fedorova, Antonina A; Goncharova, Elena P; Kovpak, Mikhail P; Vlassov, Valentin V; Zenkova, Marina A

2012-04-19

The inactivation of viral particles with agents causing minimal damage to the structure of surface epitopes is a well-established approach for the production of killed virus vaccines. Here, we describe new agents for the inactivation of influenza virus, artificial ribonucleases (aRNases), which are chemical compounds capable of cleaving RNA molecules. Several aRNases were identified, exhibiting significant virucidal activity against the influenza A virus and causing a minimal effect on the affinity of monoclonal antibodies for the inactivated virus. Using a murine model of the influenza virus infection, a high protective activity of the aRNase-inactivated virus as a vaccine was demonstrated. The results of the experiments demonstrate the efficacy of novel chemical agents in the preparation of vaccines against influenza and, perhaps, against other infections caused by RNA viruses. Copyright © 2012 Elsevier Ltd. All rights reserved.

[The great virus comeback].

Science.gov (United States)

Forterre, Patrick

2013-01-01

Viruses have been considered for a long time as by-products of biological evolution. This view is changing now as a result of several recent discoveries. Viral ecologists have shown that viral particles are the most abundant biological entities on our planet, whereas metagenomic analyses have revealed an unexpected abundance and diversity of viral genes in the biosphere. Comparative genomics have highlighted the uniqueness of viral sequences, in contradiction with the traditional view of viruses as pickpockets of cellular genes. On the contrary, cellular genomes, especially eukaryotic ones, turned out to be full of genes derived from viruses or related elements (plasmids, transposons, retroelements and so on). The discovery of unusual viruses infecting archaea has shown that the viral world is much more diverse than previously thought, ruining the traditional dichotomy between bacteriophages and viruses. Finally, the discovery of giant viruses has blurred the traditional image of viruses as small entities. Furthermore, essential clues on virus history have been obtained in the last ten years. In particular, structural analyses of capsid proteins have uncovered deeply rooted homologies between viruses infecting different cellular domains, suggesting that viruses originated before the last universal common ancestor (LUCA). These studies have shown that several lineages of viruses originated independently, i.e., viruses are polyphyletic. From the time of LUCA, viruses have coevolved with their hosts, and viral lineages can be viewed as lianas wrapping around the trunk, branches and leaves of the tree of life. Although viruses are very diverse, with genomes encoding from one to more than one thousand proteins, they can all be simply defined as organisms producing virions. Virions themselves can be defined as infectious particles made of at least one protein associated with the viral nucleic acid, endowed with the capability to protect the viral genome and ensure its

Protoplasts and plant viruses

International Nuclear Information System (INIS)

Murakishi, H.; Lesney, M.S.; Carlson, P.

1984-01-01

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

Hepatitis A Virus and Hepatitis E Virus: Emerging and Re-Emerging Enterically Transmitted Hepatitis Viruses.

Science.gov (United States)

Lemon, Stanley M; Walker, Christopher M

2018-05-07

Over the past two decades, progress in understanding human infections with hepatitis A virus (HAV) and hepatitis E virus (HEV) has been eclipsed by the priority of combating persistent hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. During that time, the global burden of liver disease caused by enteric hepatitis viruses has not abated. Because of vaccines, hepatitis A has become increasingly a disease of adults instead of early childhood in many regions of the world, resulting in an age-related shift toward more severe disease. HEV has remained endemic in many developing countries, and in well-developed, economically advanced countries it is now recognized as a cause of chronic, progressive liver disease in individuals with compromised immunity. The goal of this collection of articles is to review recent progress and to shine a bright light on gaps in our understanding of how these viruses replicate, cause disease, interact with the liver and host immune system, and are transmitted, along with prospects for improved control in human populations. Renewed efforts to study and compare HAV and HEV biology in humans and animal models have high potential to enhance our understanding of host-pathogen balance in the liver, and may contribute ultimately to the control of other infectious diseases of the liver. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

Evolutionary ecology of virus emergence.

Science.gov (United States)

Dennehy, John J

2017-02-01

The cross-species transmission of viruses into new host populations, termed virus emergence, is a significant issue in public health, agriculture, wildlife management, and related fields. Virus emergence requires overlap between host populations, alterations in virus genetics to permit infection of new hosts, and adaptation to novel hosts such that between-host transmission is sustainable, all of which are the purview of the fields of ecology and evolution. A firm understanding of the ecology of viruses and how they evolve is required for understanding how and why viruses emerge. In this paper, I address the evolutionary mechanisms of virus emergence and how they relate to virus ecology. I argue that, while virus acquisition of the ability to infect new hosts is not difficult, limited evolutionary trajectories to sustained virus between-host transmission and the combined effects of mutational meltdown, bottlenecking, demographic stochasticity, density dependence, and genetic erosion in ecological sinks limit most emergence events to dead-end spillover infections. Despite the relative rarity of pandemic emerging viruses, the potential of viruses to search evolutionary space and find means to spread epidemically and the consequences of pandemic viruses that do emerge necessitate sustained attention to virus research, surveillance, prophylaxis, and treatment. © 2016 New York Academy of Sciences.

A virus of hyperthermophilic archaea with a unique architecture among DNA viruses.

Science.gov (United States)

Rensen, Elena Ilka; Mochizuki, Tomohiro; Quemin, Emmanuelle; Schouten, Stefan; Krupovic, Mart; Prangishvili, David

2016-03-01

Viruses package their genetic material in diverse ways. Most known strategies include encapsulation of nucleic acids into spherical or filamentous virions with icosahedral or helical symmetry, respectively. Filamentous viruses with dsDNA genomes are currently associated exclusively with Archaea. Here, we describe a filamentous hyperthermophilic archaeal virus, Pyrobaculum filamentous virus 1 (PFV1), with a type of virion organization not previously observed in DNA viruses. The PFV1 virion, 400 ± 20 × 32 ± 3 nm, contains an envelope and an inner core consisting of two structural units: a rod-shaped helical nucleocapsid formed of two 14-kDa major virion proteins and a nucleocapsid-encompassing protein sheath composed of a single major virion protein of 18 kDa. The virion organization of PFV1 is superficially similar to that of negative-sense RNA viruses of the family Filoviridae, including Ebola virus and Marburg virus. The linear dsDNA of PFV1 carries 17,714 bp, including 60-bp-long terminal inverted repeats, and contains 39 predicted ORFs, most of which do not show similarities to sequences in public databases. PFV1 is a lytic virus that completely disrupts the host cell membrane at the end of the infection cycle.

DIAGNOSTICS OF VIRUS PHYTOPATHOGENS FRUIT TREE PLUM POX VIRUS, PRUNUS NECROTIC RINGSPOT VIRUS AND PRUNUS DWARF VIRUS BY BIOLOGICAL AND MOLECULAR DIAGNOSTICS

OpenAIRE

Július Rozák; Zdenka Gálová

2013-01-01

The aim of this study was to determine the incidence of viral phytopathogen Plum pox virus, Prunus necrotic ringspot virus and Prunus dwarf virus in selected localities of Slovakia and diagnose them using a molecular and biological methods. Forty samples of fruit trees of the genus Prunus, twenty samples from intensive plantings and twenty samples from wild subject were analysed. Biological diagnostic by using biological indicators Prunus persica cv. GF 305, Prunus serrulata cv. Schirofugen a...

Artificial immune system applications in computer security

CERN Document Server

Tan, Ying

2016-01-01

This book provides state-of-the-art information on the use, design, and development of the Artificial Immune System (AIS) and AIS-based solutions to computer security issues. Artificial Immune System: Applications in Computer Security focuses on the technologies and applications of AIS in malware detection proposed in recent years by the Computational Intelligence Laboratory of Peking University (CIL@PKU). It offers a theoretical perspective as well as practical solutions for readers interested in AIS, machine learning, pattern recognition and computer security. The book begins by introducing the basic concepts, typical algorithms, important features, and some applications of AIS. The second chapter introduces malware and its detection methods, especially for immune-based malware detection approaches. Successive chapters present a variety of advanced detection approaches for malware, including Virus Detection System, K-Nearest Neighbour (KNN), RBF networ s, and Support Vector Machines (SVM), Danger theory, ...

Functional properties of Virus-Encoded and Virus-Regulated 7TM Receptors

DEFF Research Database (Denmark)

Spiess, Katja; Rosenkilde, Mette Marie

2014-01-01

During co-evolution with their hosts, viruses have developed several survival strategies that involve exploitation of 7TM receptors. These include virus-encoded 7TM receptors and ligands and viral regulation of endogenous receptors. Many functional properties have been ascribed to virus-exploited...

Electron microscopic identification of Zinga virus as a strain of Rift Valley fever virus.

Science.gov (United States)

Olaleye, O D; Baigent, C L; Mueller, G; Tomori, O; Schmitz, H

1992-01-01

Electron microscopic examination of a negatively stained suspension of Zinga virus showed particles 90-100 nm in diameter, enveloped with spikes 12-20 nm in length and 5 nm in diameter. Further identification of the virus by immune electron microscopy showed the reactivity of human Rift Valley fever virus-positive serum with Zinga virus. Results of this study are in agreement with earlier reports that Zinga virus is a strain of Rift Valley fever virus.

Gender Differences in Computer Ethics among Business Administration Students

Directory of Open Access Journals (Sweden)

Ali ACILAR

2010-12-01

Full Text Available Because of the various benefits and advantages that computers and the Internet offer, these technologies have become an essential part of our daily life. The dependence on these technologies has been continuously and rapidly increasing. Computers and the Internet use also has become an important part for instructional purposes in academic environments. Even though the pervasive use of computers and the Internet has many benefits for almost everyone, but it has also increased the use of these technologies for illegal purposes or unethical activities such as spamming, making illegal copies of software, violations of privacy, hacking and computer viruses. The main purpose of this study is to explore gender differences in computer ethics among Business Administration students and examine their attitudes towards ethical use of computers. Results from 248 students in the Department of Business Administration at a public university in Turkey reveal that significant differences exist between male and female students’ attitudes towards ethical use of computers

Nonhuman Primate Models of Hepatitis A Virus and Hepatitis E Virus Infections.

Science.gov (United States)

Lanford, Robert E; Walker, Christopher M; Lemon, Stanley M

2018-04-23

Although phylogenetically unrelated, human hepatitis viruses share an exclusive or near exclusive tropism for replication in differentiated hepatocytes. This narrow tissue tropism may contribute to the restriction of the host ranges of these viruses to relatively few host species, mostly nonhuman primates. Nonhuman primate models thus figure prominently in our current understanding of the replication and pathogenesis of these viruses, including the enterically transmitted hepatitis A virus (HAV) and hepatitis E virus (HEV), and have also played major roles in vaccine development. This review draws comparisons of HAV and HEV infection from studies conducted in nonhuman primates, and describes how such studies have contributed to our current understanding of the biology of these viruses. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

OpenZika: An IBM World Community Grid Project to Accelerate Zika Virus Drug Discovery.

OpenAIRE

Sean Ekins; Alexander L Perryman; Carolina Horta Andrade

2016-01-01

The Zika virus outbreak in the Americas has caused global concern. To help accelerate this fight against Zika, we launched the OpenZika project. OpenZika is an IBM World Community Grid Project that uses distributed computing on millions of computers and Android devices to run docking experiments, in order to dock tens of millions of drug-like compounds against crystal structures and homology models of Zika proteins (and other related flavivirus targets). This will enable the identification of...

Zika Virus

Science.gov (United States)

... Funding CDC Activities For Healthcare Providers Clinical Evaluation & Disease Sexual Transmission HIV Infection & Zika Virus Testing for Zika Test Specimens – At Time of Birth Diagnostic Tests Understanding Zika Virus Test Results ...

Hepatitis C virus infection in the human immunodeficiency virus infected patient

DEFF Research Database (Denmark)

Clausen, Louise Nygaard; Lundbo, Lene Fogt; Benfield, Thomas

2014-01-01

Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) share the same transmission routes; therefore, coinfection is frequent. An estimated 5-10 million individuals alone in the western world are infected with both viruses. The majority of people acquire HCV by injection drug use and...

Immunological responses against human papilloma virus and human papilloma virus induced laryngeal cancer.

Science.gov (United States)

Chitose, Shun-ichi; Sakazaki, T; Ono, T; Kurita, T; Mihashi, H; Nakashima, T

2010-06-01

This study aimed to clarify the local immune status in the larynx in the presence of infection or carcinogenesis associated with human papilloma virus. Cytological samples (for human papilloma virus detection) and laryngeal secretions (for immunoglobulin assessment) were obtained from 31 patients with laryngeal disease, during microscopic laryngeal surgery. On histological examination, 12 patients had squamous cell carcinoma, four had laryngeal papilloma and 15 had other benign laryngeal disease. Cytological samples were tested for human papilloma virus DNA using the Hybrid Capture 2 assay. High risk human papilloma virus DNA was detected in 25 per cent of patients (three of 12) with laryngeal cancer. Low risk human papilloma virus DNA was detected only in three laryngeal papilloma patients. The mean laryngeal secretion concentrations of immunoglobulins M, G and A and secretory immunoglobulin A in human papilloma virus DNA positive patients were more than twice those in human papilloma virus DNA negative patients. A statistically significant difference was observed between the secretory immunoglobulin A concentrations in the two groups. Patients with laryngeal cancer had higher laryngeal secretion concentrations of each immunoglobulin type, compared with patients with benign laryngeal disease. The study assessed the mean laryngeal secretion concentrations of each immunoglobulin type in the 12 laryngeal cancer patients, comparing human papilloma virus DNA positive patients (n = 3) and human papilloma virus DNA negative patients (n = 9); the mean concentrations of immunoglobulins M, G and A and secretory immunoglobulin A tended to be greater in human papilloma virus DNA positive cancer patients, compared with human papilloma virus DNA negative cancer patients. These results suggest that the local laryngeal immune response is activated by infection or carcinogenesis due to human papilloma virus. The findings strongly suggest that secretory IgA has inhibitory activity

vFitness: a web-based computing tool for improving estimation of in vitro HIV-1 fitness experiments

Directory of Open Access Journals (Sweden)

Demeter Lisa

2010-05-01

Full Text Available Abstract Background The replication rate (or fitness between viral variants has been investigated in vivo and in vitro for human immunodeficiency virus (HIV. HIV fitness plays an important role in the development and persistence of drug resistance. The accurate estimation of viral fitness relies on complicated computations based on statistical methods. This calls for tools that are easy to access and intuitive to use for various experiments of viral fitness. Results Based on a mathematical model and several statistical methods (least-squares approach and measurement error models, a Web-based computing tool has been developed for improving estimation of virus fitness in growth competition assays of human immunodeficiency virus type 1 (HIV-1. Conclusions Unlike the two-point calculation used in previous studies, the estimation here uses linear regression methods with all observed data in the competition experiment to more accurately estimate relative viral fitness parameters. The dilution factor is introduced for making the computational tool more flexible to accommodate various experimental conditions. This Web-based tool is implemented in C# language with Microsoft ASP.NET, and is publicly available on the Web at http://bis.urmc.rochester.edu/vFitness/.

Deep-Sea Hydrothermal Vent Viruses Compensate for Microbial Metabolism in Virus-Host Interactions.

Science.gov (United States)

He, Tianliang; Li, Hongyun; Zhang, Xiaobo

2017-07-11

Viruses are believed to be responsible for the mortality of host organisms. However, some recent investigations reveal that viruses may be essential for host survival. To date, it remains unclear whether viruses are beneficial or harmful to their hosts. To reveal the roles of viruses in the virus-host interactions, viromes and microbiomes of sediment samples from three deep-sea hydrothermal vents were explored in this study. To exclude the influence of exogenous DNAs on viromes, the virus particles were purified with nuclease (DNase I and RNase A) treatments and cesium chloride density gradient centrifugation. The metagenomic analysis of viromes without exogenous DNA contamination and microbiomes of vent samples indicated that viruses had compensation effects on the metabolisms of their host microorganisms. Viral genes not only participated in most of the microbial metabolic pathways but also formed branched pathways in microbial metabolisms, including pyrimidine metabolism; alanine, aspartate, and glutamate metabolism; nitrogen metabolism and assimilation pathways of the two-component system; selenocompound metabolism; aminoacyl-tRNA biosynthesis; and amino sugar and nucleotide sugar metabolism. As is well known, deep-sea hydrothermal vent ecosystems exist in relatively isolated environments which are barely influenced by other ecosystems. The metabolic compensation of hosts mediated by viruses might represent a very important aspect of virus-host interactions. IMPORTANCE Viruses are the most abundant biological entities in the oceans and have very important roles in regulating microbial community structure and biogeochemical cycles. The relationship between virus and host microbes is broadly thought to be that of predator and prey. Viruses can lyse host cells to control microbial population sizes and affect community structures of hosts by killing specific microbes. However, viruses also influence their hosts through manipulation of bacterial metabolism. We found

Viruses in reptiles.

Science.gov (United States)

Ariel, Ellen

2011-09-21

The etiology of reptilian viral diseases can be attributed to a wide range of viruses occurring across different genera and families. Thirty to forty years ago, studies of viruses in reptiles focused mainly on the zoonotic potential of arboviruses in reptiles and much effort went into surveys and challenge trials of a range of reptiles with eastern and western equine encephalitis as well as Japanese encephalitis viruses. In the past decade, outbreaks of infection with West Nile virus in human populations and in farmed alligators in the USA has seen the research emphasis placed on the issue of reptiles, particularly crocodiles and alligators, being susceptible to, and reservoirs for, this serious zoonotic disease. Although there are many recognised reptilian viruses, the evidence for those being primary pathogens is relatively limited. Transmission studies establishing pathogenicity and cofactors are likewise scarce, possibly due to the relatively low commercial importance of reptiles, difficulties with the availability of animals and permits for statistically sound experiments, difficulties with housing of reptiles in an experimental setting or the inability to propagate some viruses in cell culture to sufficient titres for transmission studies. Viruses as causes of direct loss of threatened species, such as the chelonid fibropapilloma associated herpesvirus and ranaviruses in farmed and wild tortoises and turtles, have re-focused attention back to the characterisation of the viruses as well as diagnosis and pathogenesis in the host itself.

The 3′ Untranslated Region of Tobacco Necrosis Virus RNA Contains a Barley Yellow Dwarf Virus-Like Cap-Independent Translation Element

Science.gov (United States)

Shen, Ruizhong; Miller, W. Allen

2004-01-01

RNAs of many viruses are translated efficiently in the absence of a 5′ cap structure. The tobacco necrosis virus (TNV) genome is an uncapped, nonpolyadenylated RNA whose translation mechanism has not been well investigated. Computational analysis predicted a cap-independent translation element (TE) within the 3′ untranslated region (3′ UTR) of TNV RNA that resembles the TE of barley yellow dwarf virus (BYDV), a luteovirus. Here we report that such a TE does indeed exist in the 3′ UTR of TNV strain D. Like the BYDV TE, the TNV TE (i) functions both in vitro and in vivo, (ii) requires additional sequence for cap-independent translation in vivo, (iii) has a similar secondary structure and the conserved sequence CGGAUCCUGGGAAACAGG, (iv) is inactivated by a four-base duplication in this conserved sequence, (v) can function in the 5′ UTR, and (vi) when located in its natural 3′ location, may form long-distance base pairing with the viral 5′ UTR that is conserved and probably required. The TNV TE differs from the BYDV TE by having only three helical domains instead of four. Similar structures were found in all members of the Necrovirus genus of the Tombusviridae family, except satellite tobacco necrosis virus, which harbors a different 3′ cap-independent translation domain. The presence of the BYDV-like TE in select genera of different families indicates that phylogenetic distribution of TEs does not follow standard viral taxonomic relationships. We propose a new class of cap-independent TE called BYDV-like TE. PMID:15078948

A REVIEW ON ZIKA VIRUS (ZIKV) -A DREADFUL MEMBER OF THE VIRUS FAMILY FLAVIVIRIDAE

OpenAIRE

1Rafiya Begum, 2 Raafia Aseena, 3Nuha Rasheed and 4 Abdul Saleem Mohammad

2017-01-01

Research on zika virus examine the virus that is spread to humans through a mosquito bite, with symptoms that include fever, rash, joint pain, and conjuctivities. For most people zika virus is not necessarily anything to worry, as it is not fatal and symptoms are generally mild for period up to a week. Hospitalization because of zika virus is almost always not necessary. However, the zika virus can be extremely dangerous to pregnant womes. Key Words: Zika, virus, transmission, fatal, flavivir...

Type C virus activation in nontransformed mouse cells by uv-irradiated herpes simplex virus

Energy Technology Data Exchange (ETDEWEB)

Hampar, B. (National Institutes of Health, Bethesda, MD); Hatanaka, M.; Aulakh, G.; Derge, J.G.; Lee, L.; Showalter, S.

1977-02-01

Infection of nontransformed mouse cells with uv-irradiated herpes simplex virus (uv-HSV) resulted in the activation of an endogenous xenotropic (x-tropic) type C virus. Synthesis of type C virus persisted for only a few days, with most of the virus remaining cell associated. The levels of type C virus activated by uv-HSV varied depending on the multiplicity of infection (m.o.i.) and the uv dose. At low uv doses, where cell killing occurred, little or no type C virus synthesis was observed. Maximum levels of type C virus synthesis were observed with the minimum uv dose which eliminated cell killing by HSV. Synthesis of type C virus, albeit at lower levels, was still observed at uv doses beyond those required to prevent cell killing.

Type C virus activation in nontransformed mouse cells by uv-irradiated herpes simplex virus

International Nuclear Information System (INIS)

Hampar, B.; Hatanaka, M.; Aulakh, G.; Derge, J.G.; Lee, L.; Showalter, S.

1977-01-01

Infection of nontransformed mouse cells with uv-irradiated herpes simplex virus (uv-HSV) resulted in the activation of an endogenous xenotropic (x-tropic) type C virus. Synthesis of type C virus persisted for only a few days, with most of the virus remaining cell associated. The levels of type C virus activated by uv-HSV varied depending on the multiplicity of infection (m.o.i.) and the uv dose. At low uv doses, where cell killing occurred, little or no type C virus synthesis was observed. Maximum levels of type C virus synthesis were observed with the minimum uv dose which eliminated cell killing by HSV. Synthesis of type C virus, albeit at lower levels, was still observed at uv doses beyond those required to prevent cell killing

A Lagrangian particle model to predict the airborne spread of foot-and-mouth disease virus

Science.gov (United States)

Mayer, D.; Reiczigel, J.; Rubel, F.

Airborne spread of bioaerosols in the boundary layer over a complex terrain is simulated using a Lagrangian particle model, and applied to modelling the airborne spread of foot-and-mouth disease (FMD) virus. Two case studies are made with study domains located in a hilly region in the northwest of the Styrian capital Graz, the second largest town in Austria. Mountainous terrain as well as inhomogeneous and time varying meteorological conditions prevent from application of so far used Gaussian dispersion models, while the proposed model can handle these realistically. In the model, trajectories of several thousands of particles are computed and the distribution of virus concentration near the ground is calculated. This allows to assess risk of infection areas with respect to animal species of interest, such as cattle, swine or sheep. Meteorological input data like wind field and other variables necessary to compute turbulence were taken from the new pre-operational version of the non-hydrostatic numerical weather prediction model LMK ( Lokal-Modell-Kürzestfrist) running at the German weather service DWD ( Deutscher Wetterdienst). The LMK model provides meteorological parameters with a spatial resolution of about 2.8 km. To account for the spatial resolution of 400 m used by the Lagrangian particle model, the initial wind field is interpolated upon the finer grid by a mass consistent interpolation method. Case studies depict a significant influence of local wind systems on the spread of virus. Higher virus concentrations at the upwind side of the hills and marginal concentrations in the lee are well observable, as well as canalization effects by valleys. The study demonstrates that the Lagrangian particle model is an appropriate tool for risk assessment of airborne spread of virus by taking into account the realistic orographic and meteorological conditions.

Chikungunya virus

Science.gov (United States)

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

Perinatal hepatitis B virus detection by hepatitis B virus-DNA analysis.

OpenAIRE

De Virgiliis, S; Frau, F; Sanna, G; Turco, M P; Figus, A L; Cornacchia, G; Cao, A

1985-01-01

Maternal transmission of hepatitis B virus infection in relation to the hepatitis B e antigen/antibody system and serum hepatitis B virus-DNA were evaluated. Results indicate that hepatitis B virus-DNA analysis can identify hepatitis B serum antigen positive mothers who may transmit infection to their offspring.

Virus like particle-based vaccines against emerging infectious disease viruses.

Science.gov (United States)

Liu, Jinliang; Dai, Shiyu; Wang, Manli; Hu, Zhihong; Wang, Hualin; Deng, Fei

2016-08-01

Emerging infectious diseases are major threats to human health. Most severe viral disease outbreaks occur in developing regions where health conditions are poor. With increased international travel and business, the possibility of eventually transmitting infectious viruses between different countries is increasing. The most effective approach in preventing viral diseases is vaccination. However, vaccines are not currently available for numerous viral diseases. Virus-like particles (VLPs) are engineered vaccine candidates that have been studied for decades. VLPs are constructed by viral protein expression in various expression systems that promote the selfassembly of proteins into structures resembling virus particles. VLPs have antigenicity similar to that of the native virus, but are non-infectious as they lack key viral genetic material. VLP vaccines have attracted considerable research interest because they offer several advantages over traditional vaccines. Studies have shown that VLP vaccines can stimulate both humoral and cellular immune responses, which may offer effective antiviral protection. Here we review recent developments with VLP-based vaccines for several highly virulent emerging or re-emerging infectious diseases. The infectious agents discussed include RNA viruses from different virus families, such as the Arenaviridae, Bunyaviridae, Caliciviridae, Coronaviridae, Filoviridae, Flaviviridae, Orthomyxoviridae, Paramyxoviridae, and Togaviridae families.

Immunogenicity of a modified-live virus vaccine against bovine viral diarrhea virus types 1 and 2, infectious bovine rhinotracheitis virus, bovine parainfluenza-3 virus, and bovine respiratory syncytial virus when administered intranasally in young calves.

Science.gov (United States)

Xue, Wenzhi; Ellis, John; Mattick, Debra; Smith, Linda; Brady, Ryan; Trigo, Emilio

2010-05-14

The immunogenicity of an intranasally-administered modified-live virus (MLV) vaccine in 3-8 day old calves was evaluated against bovine viral diarrhea virus (BVDV) types 1 and 2, infectious bovine rhinotracheitis (IBR) virus, parainfluenza-3 (PI-3) virus and bovine respiratory syncytial virus (BRSV). Calves were intranasally vaccinated with a single dose of a multivalent MLV vaccine and were challenged with one of the respective viruses three to four weeks post-vaccination in five separate studies. There was significant sparing of diseases in calves intranasally vaccinated with the MLV vaccine, as indicated by significantly fewer clinical signs, lower rectal temperatures, reduced viral shedding, greater white blood cell and platelet counts, and less severe pulmonary lesions than control animals. This was the first MLV combination vaccine to demonstrate efficacy against BVDV types 1 and 2, IBR, PI-3 and BRSV in calves 3-8 days of age. Copyright 2010 Elsevier Ltd. All rights reserved.

Ocular Tropism of Respiratory Viruses

Science.gov (United States)

Rota, Paul A.; Tumpey, Terrence M.

2013-01-01

SUMMARY Respiratory viruses (including adenovirus, influenza virus, respiratory syncytial virus, coronavirus, and rhinovirus) cause a broad spectrum of disease in humans, ranging from mild influenza-like symptoms to acute respiratory failure. While species D adenoviruses and subtype H7 influenza viruses are known to possess an ocular tropism, documented human ocular disease has been reported following infection with all principal respiratory viruses. In this review, we describe the anatomical proximity and cellular receptor distribution between ocular and respiratory tissues. All major respiratory viruses and their association with human ocular disease are discussed. Research utilizing in vitro and in vivo models to study the ability of respiratory viruses to use the eye as a portal of entry as well as a primary site of virus replication is highlighted. Identification of shared receptor-binding preferences, host responses, and laboratory modeling protocols among these viruses provides a needed bridge between clinical and laboratory studies of virus tropism. PMID:23471620

Understanding Ebola Virus Transmission

Directory of Open Access Journals (Sweden)

Seth Judson

2015-02-01

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

Ganjam virus/Nairobi sheep disease virus induces a pro-inflammatory response in infected sheep

OpenAIRE

bin Tarif, Abid; Lasecka, Lidia; Holzer, Barbara; Baron, Michael D

2012-01-01

Abstract Partly due to climate change, and partly due to changes of human habitat occupation, the impact of tick-borne viruses is increasing. Nairobi sheep disease virus (NSDV) and Ganjam virus (GV) are two names for the same virus, which causes disease in sheep and goats and is currently known to be circulating in India and East Africa. The virus is transmitted by ixodid ticks and causes a severe hemorrhagic disease. We have developed a real-time PCR assay for the virus genome and validated ...

Zika Virus

Science.gov (United States)

... through blood transfusions. There have been outbreaks of Zika virus in the United States, Africa, Southeast Asia, the ... not travel to areas where there is a Zika virus outbreak. If you do decide to travel, first ...

Ganjam virus/Nairobi sheep disease virus induces a pro-inflammatory response in infected sheep

Directory of Open Access Journals (Sweden)

bin Tarif Abid

2012-10-01

Full Text Available Abstract Partly due to climate change, and partly due to changes of human habitat occupation, the impact of tick-borne viruses is increasing. Nairobi sheep disease virus (NSDV and Ganjam virus (GV are two names for the same virus, which causes disease in sheep and goats and is currently known to be circulating in India and East Africa. The virus is transmitted by ixodid ticks and causes a severe hemorrhagic disease. We have developed a real-time PCR assay for the virus genome and validated it in a pilot study of the pathogenicity induced by two different isolates of NSDV/GV. One isolate was highly adapted to tissue culture, grew in most cell lines tested, and was essentially apathogenic in sheep. The second isolate appeared to be poorly adapted to cell culture and retained pathogenicity in sheep. The real-time PCR assay for virus easily detected 4 copies or less of the viral genome, and allowed a quantitative measure of the virus in whole blood. Measurement of the changes in cytokine mRNAs showed similar changes to those observed in humans infected by the closely related virus Crimean Congo hemorrhagic fever virus.

Ganjam virus/Nairobi sheep disease virus induces a pro-inflammatory response in infected sheep.

Science.gov (United States)

Bin Tarif, Abid; Lasecka, Lidia; Holzer, Barbara; Baron, Michael D

2012-10-19

Partly due to climate change, and partly due to changes of human habitat occupation, the impact of tick-borne viruses is increasing. Nairobi sheep disease virus (NSDV) and Ganjam virus (GV) are two names for the same virus, which causes disease in sheep and goats and is currently known to be circulating in India and East Africa. The virus is transmitted by ixodid ticks and causes a severe hemorrhagic disease. We have developed a real-time PCR assay for the virus genome and validated it in a pilot study of the pathogenicity induced by two different isolates of NSDV/GV. One isolate was highly adapted to tissue culture, grew in most cell lines tested, and was essentially apathogenic in sheep. The second isolate appeared to be poorly adapted to cell culture and retained pathogenicity in sheep. The real-time PCR assay for virus easily detected 4 copies or less of the viral genome, and allowed a quantitative measure of the virus in whole blood. Measurement of the changes in cytokine mRNAs showed similar changes to those observed in humans infected by the closely related virus Crimean Congo hemorrhagic fever virus.

Transmission of Influenza A Viruses

Science.gov (United States)

Neumann, Gabriele; Kawaoka, Yoshihiro

2015-01-01

Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to ‘novel’ viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

New frontiers in oncolytic viruses: optimizing and selecting for virus strains with improved efficacy

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Lundstrom K

2018-02-01

Full Text Available Kenneth Lundstrom PanTherapeutics, Lutry, Switzerland Abstract: Oncolytic viruses have demonstrated selective replication and killing of tumor cells. Different types of oncolytic viruses – adenoviruses, alphaviruses, herpes simplex viruses, Newcastle disease viruses, rhabdoviruses, Coxsackie viruses, and vaccinia viruses – have been applied as either naturally occurring or engineered vectors. Numerous studies in animal-tumor models have demonstrated substantial tumor regression and prolonged survival rates. Moreover, clinical trials have confirmed good safety profiles and therapeutic efficacy for oncolytic viruses. Most encouragingly, the first cancer gene-therapy drug – Gendicine, based on oncolytic adenovirus type 5 – was approved in China. Likewise, a second-generation oncolytic herpes simplex virus-based drug for the treatment of melanoma has been registered in the US and Europe as talimogene laherparepvec. Keywords: immunotherapy, viral vectors, clinical trials, drug approval

Computer technology and the surgeon: what the resident needs to ...

African Journals Online (AJOL)

Though a compliment to the surgeon, it has its problems including overwhelming information requiring careful scrutiny; computer fraud, hacking and viruses; copyright laws; the 'threat' of a well-informed patient population; and the risk of over dependence. Surgery in Nigeria and most of African is yet to maximize its benefits.

Postmortem stability of Ebola virus.

Science.gov (United States)

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

2015-05-01

The ongoing Ebola virus outbreak in West Africa has highlighted questions regarding stability of the virus and detection of RNA from corpses. We used Ebola virus-infected macaques to model humans who died of Ebola virus disease. Viable virus was isolated <7 days posteuthanasia; viral RNA was detectable for 10 weeks.

A Foxtail mosaic virus Vector for Virus-Induced Gene Silencing in Maize.

Science.gov (United States)

Mei, Yu; Zhang, Chunquan; Kernodle, Bliss M; Hill, John H; Whitham, Steven A

2016-06-01

Plant viruses have been widely used as vectors for foreign gene expression and virus-induced gene silencing (VIGS). A limited number of viruses have been developed into viral vectors for the purposes of gene expression or VIGS in monocotyledonous plants, and among these, the tripartite viruses Brome mosaic virus and Cucumber mosaic virus have been shown to induce VIGS in maize (Zea mays). We describe here a new DNA-based VIGS system derived from Foxtail mosaic virus (FoMV), a monopartite virus that is able to establish systemic infection and silencing of endogenous maize genes homologous to gene fragments inserted into the FoMV genome. To demonstrate VIGS applications of this FoMV vector system, four genes, phytoene desaturase (functions in carotenoid biosynthesis), lesion mimic22 (encodes a key enzyme of the porphyrin pathway), iojap (functions in plastid development), and brown midrib3 (caffeic acid O-methyltransferase), were silenced and characterized in the sweet corn line Golden × Bantam. Furthermore, we demonstrate that the FoMV infectious clone establishes systemic infection in maize inbred lines, sorghum (Sorghum bicolor), and green foxtail (Setaria viridis), indicating the potential wide applications of this viral vector system for functional genomics studies in maize and other monocots. © 2016 American Society of Plant Biologists. All Rights Reserved.

Engineering development of avian influenza virus detection system in a patient's body

International Nuclear Information System (INIS)

Budi Santoso; Romadhon; Sukandar; Istofa

2010-01-01

The avian influenza virus detection equipment in a patient's body has been made. Currently, detection of avian influenza virus carried out by expensive laboratory equipment's, so only certain hospitals can perform this detection. This developing equipment is expected to be cheaper than existing equipment and the diagnosis can be known immediately. The sensing device is made using the principle of nuclear radiation detection. Radiation comes from a drunk labelled tamiflu (oseltamivir) which is drunk to the patient. Tamiflu is a drug to catch, H5N1 viruses in a patient's body. A labelled tamiflu is tamiflu which is labelled by I-131 radioisotopes. The presence of virus in the body is proportional to the amount of radiation captured by the detector. The equipment is composed of a Geiger-Mueller (GM) pancake detector type, a signal processor, a counter, and a data processor (computer). The GM detector converts the radiation that comes into electrical signals. Electrical signal is then converted into TTL level pulses by the signal processor. Pulse counting results are processed by data processor. The total count is proportional to the amount of virus captured by labelled tamiflu. The measurement threshold can be set by medical officer through software. At a certain threshold can be inferred identified patients infected with avian influenza virus. If the measurement below the threshold means that the patient is still within safe limits. This equipment is expected to create avian influenza virus detection system that cheaply and quickly so that more and more hospitals are using to detect the avian influenza virus. (author)

Understanding the Perpetration of Employee Computer Crime in the Organisational Context

DEFF Research Database (Denmark)

Willison, Robert Andrew

2006-01-01

While hackers and viruses fuel the IS security concerns for organisations, the problems posed by employee computer crime should not be underestimated. Indeed, a growing number of IS security researchers have turned their attention to the `insider' threat. However, to date, there has been a lack...

SCHEMA computational design of virus capsid chimeras: calibrating how genome packaging, protection, and transduction correlate with calculated structural disruption.

Science.gov (United States)

Ho, Michelle L; Adler, Benjamin A; Torre, Michael L; Silberg, Jonathan J; Suh, Junghae

2013-12-20

Adeno-associated virus (AAV) recombination can result in chimeric capsid protein subunits whose ability to assemble into an oligomeric capsid, package a genome, and transduce cells depends on the inheritance of sequence from different AAV parents. To develop quantitative design principles for guiding site-directed recombination of AAV capsids, we have examined how capsid structural perturbations predicted by the SCHEMA algorithm correlate with experimental measurements of disruption in seventeen chimeric capsid proteins. In our small chimera population, created by recombining AAV serotypes 2 and 4, we found that protection of viral genomes and cellular transduction were inversely related to calculated disruption of the capsid structure. Interestingly, however, we did not observe a correlation between genome packaging and calculated structural disruption; a majority of the chimeric capsid proteins formed at least partially assembled capsids and more than half packaged genomes, including those with the highest SCHEMA disruption. These results suggest that the sequence space accessed by recombination of divergent AAV serotypes is rich in capsid chimeras that assemble into 60-mer capsids and package viral genomes. Overall, the SCHEMA algorithm may be useful for delineating quantitative design principles to guide the creation of libraries enriched in genome-protecting virus nanoparticles that can effectively transduce cells. Such improvements to the virus design process may help advance not only gene therapy applications but also other bionanotechnologies dependent upon the development of viruses with new sequences and functions.

Efficient production of infectious viruses requires enzymatic activity of Epstein-Barr virus protein kinase.

Science.gov (United States)

Murata, Takayuki; Isomura, Hiroki; Yamashita, Yoriko; Toyama, Shigenori; Sato, Yoshitaka; Nakayama, Sanae; Kudoh, Ayumi; Iwahori, Satoko; Kanda, Teru; Tsurumi, Tatsuya

2009-06-20

The Epstein-Barr virus (EBV) BGLF4 gene product is the only protein kinase encoded by the virus genome. In order to elucidate its physiological roles in viral productive replication, we here established a BGLF4-knockout mutant and a revertant virus. While the levels of viral DNA replication of the deficient mutant were equivalent to those of the wild-type and the revertant, virus production was significantly impaired. Expression of the BGLF4 protein in trans fully complemented the low yield of the mutant virus, while expression of a kinase-dead (K102I) form of the protein failed to restore the virus titer. These results demonstrate that BGLF4 plays a significant role in production of infectious viruses and that the kinase activity is crucial.

Viruses infecting marine molluscs.

Science.gov (United States)

Arzul, Isabelle; Corbeil, Serge; Morga, Benjamin; Renault, Tristan

2017-07-01

Although a wide range of viruses have been reported in marine molluscs, most of these reports rely on ultrastructural examination and few of these viruses have been fully characterized. The lack of marine mollusc cell lines restricts virus isolation capacities and subsequent characterization works. Our current knowledge is mostly restricted to viruses affecting farmed species such as oysters Crassostrea gigas, abalone Haliotis diversicolor supertexta or the scallop Chlamys farreri. Molecular approaches which are needed to identify virus affiliation have been carried out for a small number of viruses, most of them belonging to the Herpesviridae and birnaviridae families. These last years, the use of New Generation Sequencing approach has allowed increasing the number of sequenced viral genomes and has improved our capacity to investigate the diversity of viruses infecting marine molluscs. This new information has in turn allowed designing more efficient diagnostic tools. Moreover, the development of experimental infection protocols has answered some questions regarding the pathogenesis of these viruses and their interactions with their hosts. Control and management of viral diseases in molluscs mostly involve active surveillance, implementation of effective bio security measures and development of breeding programs. However factors triggering pathogen development and the life cycle and status of the viruses outside their mollusc hosts still need further investigations. Copyright © 2017 Elsevier Inc. All rights reserved.

Designing cyclopentapeptide inhibitor as potential antiviral drug for dengue virus ns5 methyltransferase.

Science.gov (United States)

Idrus, Syarifuddin; Tambunan, Usman Sumo Friend; Zubaidi, Ahmad Ardilla

2012-01-01

NS5 methyltransferase (Mtase) has a crucial role in the replication of dengue virus. There are two active sites on NS5 Mtase i.e., SAM and RNA-cap binding sites. Inhibition of the NS5 Mtase activity is expected to prevent the propagation of dengue virus. This study was conducted to design cyclic peptide ligands as enzyme inhibitors of dengue virus NS5 Mtase through computational approach. Cyclopentapeptides were designed as ligand of SAM binding site as much as 1635 and 736 cyclopentpeptides were designed as ligand of RNA-cap binding site. Interaction between ligand and NS5 Mtase has been conducted on the Docking simulation. The result shows that cyclopentapeptide CTWYC was the best peptide candidate on SAM binding site, with estimated free binding energy -30.72 kca/mol. Cyclopentapeptide CYEFC was the best peptide on RNA-cap binding site with estimated free binding energy -22.89 kcal/mol. Both peptides did not have tendency toward toxicity properties. So it is expected that both CTWYC and CYEFC ligands could be used as a potential antiviral drug candidates, which can inhibit the SAM and RNA-cap binding sites of dengue virus NS5 Mtase.

Coinfection with Epstein–Barr Virus (EBV), Human Papilloma Virus (HPV) and Polyoma BK Virus (BKPyV) in Laryngeal, Oropharyngeal and Oral Cavity Cancer

OpenAIRE

Drop, Bartłomiej; Strycharz-Dudziak, Małgorzata; Kliszczewska, Ewa; Polz-Dacewicz, Małgorzata

2017-01-01

Most research providing evidence for the role of oncogenic viruses in head and neck squamous cell carcinoma (SCC) development is focused on one type of virus without analyzing possible interactions between two or more types of viruses. The aim of this study was to analyse the prevalence of co-infection with human papillomavirus (HPV), Epstein–Barr virus (EBV) and polyoma BK virus (BKPyV) in oral, oropharyngeal and laryngeal squamous cell carcinomas in Polish patients. The correlations between...

RNA viruses in the sea.

Science.gov (United States)

Lang, Andrew S; Rise, Matthew L; Culley, Alexander I; Steward, Grieg F

2009-03-01

Viruses are ubiquitous in the sea and appear to outnumber all other forms of marine life by at least an order of magnitude. Through selective infection, viruses influence nutrient cycling, community structure, and evolution in the ocean. Over the past 20 years we have learned a great deal about the diversity and ecology of the viruses that constitute the marine virioplankton, but until recently the emphasis has been on DNA viruses. Along with expanding knowledge about RNA viruses that infect important marine animals, recent isolations of RNA viruses that infect single-celled eukaryotes and molecular analyses of the RNA virioplankton have revealed that marine RNA viruses are novel, widespread, and genetically diverse. Discoveries in marine RNA virology are broadening our understanding of the biology, ecology, and evolution of viruses, and the epidemiology of viral diseases, but there is still much that we need to learn about the ecology and diversity of RNA viruses before we can fully appreciate their contributions to the dynamics of marine ecosystems. As a step toward making sense of how RNA viruses contribute to the extraordinary viral diversity in the sea, we summarize in this review what is currently known about RNA viruses that infect marine organisms.

Reverse genetics of measles virus and resulting multivalent recombinant vaccines: applications of recombinant measles viruses.

Science.gov (United States)

Billeter, M A; Naim, H Y; Udem, S A

2009-01-01

An overview is given on the development of technologies to allow reverse genetics of RNA viruses, i.e., the rescue of viruses from cDNA, with emphasis on nonsegmented negative-strand RNA viruses (Mononegavirales), as exemplified for measles virus (MV). Primarily, these technologies allowed site-directed mutagenesis, enabling important insights into a variety of aspects of the biology of these viruses. Concomitantly, foreign coding sequences were inserted to (a) allow localization of virus replication in vivo through marker gene expression, (b) develop candidate multivalent vaccines against measles and other pathogens, and (c) create candidate oncolytic viruses. The vector use of these viruses was experimentally encouraged by the pronounced genetic stability of the recombinants unexpected for RNA viruses, and by the high load of insertable genetic material, in excess of 6 kb. The known assets, such as the small genome size of the vector in comparison to DNA viruses proposed as vectors, the extensive clinical experience of attenuated MV as vaccine with a proven record of high safety and efficacy, and the low production cost per vaccination dose are thus favorably complemented.

Schmallenberg Virus

Indian Academy of Sciences (India)

IAS Admin

explore the potential of this infection crossing the species barrier and thereby .... The virus targets mainly the brain of the unborn animal resulting in neurological ... The virus is located in the blood of the adult infected animal or in the central ...

A combination in-ovo vaccine for avian influenza virus and Newcastle disease virus.

Science.gov (United States)

Steel, John; Burmakina, Svetlana V; Thomas, Colleen; Spackman, Erica; García-Sastre, Adolfo; Swayne, David E; Palese, Peter

2008-01-24

The protection of poultry from H5N1 highly pathogenic avian influenza A (HPAI) and Newcastle disease virus (NDV) can be achieved through vaccination, as part of a broader disease control strategy. We have previously generated a recombinant influenza virus expressing, (i) an H5 hemagglutinin protein, modified by the removal of the polybasic cleavage peptide and (ii) the ectodomain of the NDV hemagglutinin-neuraminidase (HN) protein in the place of the ectodomain of influenza neuraminidase (Park MS, et al. Proc Natl Acad Sci USA 2006;103(21):8203-8). Here we show this virus is attenuated in primary normal human bronchial epithelial (NHBE) cell culture, and demonstrate protection of C57BL/6 mice from lethal challenge with an H5 HA-containing influenza virus through immunisation with the recombinant virus. In addition, in-ovo vaccination of 18-day-old embryonated chicken eggs provided 90% and 80% protection against highly stringent lethal challenge by NDV and H5N1 virus, respectively. We propose that this virus has potential as a safe in-ovo live, attenuated, bivalent avian influenza and Newcastle disease virus vaccine.

Evaluation of the suitability of a plant virus, pepper mild mottle virus, as a surrogate of human enteric viruses for assessment of the efficacy of coagulation-rapid sand filtration to remove those viruses.

Science.gov (United States)

Shirasaki, N; Matsushita, T; Matsui, Y; Yamashita, R

2018-02-01

Here, we evaluated the removal of three representative human enteric viruses - adenovirus (AdV) type 40, coxsackievirus (CV) B5, and hepatitis A virus (HAV) IB - and one surrogate of human caliciviruses - murine norovirus (MNV) type 1 - by coagulation-rapid sand filtration, using water samples from eight water sources for drinking water treatment plants in Japan. The removal ratios of a plant virus (pepper mild mottle virus; PMMoV) and two bacteriophages (MS2 and φX174) were compared with the removal ratios of human enteric viruses to assess the suitability of PMMoV, MS2, and φX174 as surrogates for human enteric viruses. The removal ratios of AdV, CV, HAV, and MNV, evaluated via the real-time polymerase chain reaction (PCR) method, were 0.8-2.5-log 10 when commercially available polyaluminum chloride (PACl, basicity 1.5) and virgin silica sand were used as the coagulant and filter medium, respectively. The type of coagulant affected the virus removal efficiency, but the age of silica sand used in the rapid sand filtration did not. Coagulation-rapid sand filtration with non-sulfated, high-basicity PACls (basicity 2.1 or 2.5) removed viruses more efficiently than the other aluminum-based coagulants. The removal ratios of MS2 were sometimes higher than those of the three human enteric viruses and MNV, whereas the removal ratios of φX174 tended to be smaller than those of the three human enteric viruses and MNV. In contrast, the removal ratios of PMMoV were similar to and strongly correlated with those of the three human enteric viruses and MNV. Thus, PMMoV appears to be a suitable surrogate for human enteric viruses for the assessment of the efficacy of coagulation-rapid sand filtration to remove viruses. Copyright © 2017 Elsevier Ltd. All rights reserved.

Computer forensics an essential guide for accountants, lawyers, and managers

CERN Document Server

Sheetz, Michael

2013-01-01

Would your company be prepared in the event of: * Computer-driven espionage * A devastating virus attack * A hacker's unauthorized access * A breach of data security? As the sophistication of computer technology has grown, so has the rate of computer-related criminal activity. Subsequently, American corporations now lose billions of dollars a year to hacking, identity theft, and other computer attacks. More than ever, businesses and professionals responsible for the critical data of countless customers and employees need to anticipate and safeguard against computer intruders and attacks. The first book to successfully speak to the nontechnical professional in the fields of business and law on the topic of computer crime, Computer Forensics: An Essential Guide for Accountants, Lawyers, and Managers provides valuable advice on the hidden difficulties that can blindside companies and result in damaging costs. Written by industry expert Michael Sheetz, this important book provides readers with an honest look at t...

An inactivated whole-virus porcine parvovirus vaccine protects pigs against disease but does not prevent virus shedding even after homologous virus challenge.

Science.gov (United States)

Foerster, Tessa; Streck, André Felipe; Speck, Stephanie; Selbitz, Hans-Joachim; Lindner, Thomas; Truyen, Uwe

2016-06-01

Inactivated whole-virus vaccines against porcine parvovirus (PPV) can prevent disease but not infection and virus shedding after heterologous virus challenge. Here, we showed that the same is true for a homologous challenge. Pregnant sows were vaccinated with an experimental inactivated vaccine based on PPV strain 27a. They were challenged on day 40 of gestation with the virulent porcine parvovirus PPV-27a from which the vaccine was prepared (homologous challenge). On day 90 of gestation, the fetuses from vaccinated sows were protected against disease, while the fetuses of the non-vaccinated sows (control group) exhibited signs of parvovirus disease. All gilts, whether vaccinated or not vaccinated, showed a boost of PPV-specific antibodies indicative of virus infection and replication. Low DNA copy numbers, but not infectious virus, could be demonstrated in nasal or rectal swabs of immunized sows, but high copy numbers of challenge virus DNA as well as infectious virus could both be demonstrated in non-vaccinated sows.

Dinucleotide Composition in Animal RNA Viruses Is Shaped More by Virus Family than by Host Species.

Science.gov (United States)

Di Giallonardo, Francesca; Schlub, Timothy E; Shi, Mang; Holmes, Edward C

2017-04-15

Viruses use the cellular machinery of their hosts for replication. It has therefore been proposed that the nucleotide and dinucleotide compositions of viruses should match those of their host species. If this is upheld, it may then be possible to use dinucleotide composition to predict the true host species of viruses sampled in metagenomic surveys. However, it is also clear that different taxonomic groups of viruses tend to have distinctive patterns of dinucleotide composition that may be independent of host species. To determine the relative strength of the effect of host versus virus family in shaping dinucleotide composition, we performed a comparative analysis of 20 RNA virus families from 15 host groupings, spanning two animal phyla and more than 900 virus species. In particular, we determined the odds ratios for the 16 possible dinucleotides and performed a discriminant analysis to evaluate the capability of virus dinucleotide composition to predict the correct virus family or host taxon from which it was isolated. Notably, while 81% of the data analyzed here were predicted to the correct virus family, only 62% of these data were predicted to their correct subphylum/class host and a mere 32% to their correct mammalian order. Similarly, dinucleotide composition has a weak predictive power for different hosts within individual virus families. We therefore conclude that dinucleotide composition is generally uniform within a virus family but less well reflects that of its host species. This has obvious implications for attempts to accurately predict host species from virus genome sequences alone. IMPORTANCE Determining the processes that shape virus genomes is central to understanding virus evolution and emergence. One question of particular importance is why nucleotide and dinucleotide frequencies differ so markedly between viruses. In particular, it is currently unclear whether host species or virus family has the biggest impact on dinucleotide frequencies and

Monoclonal antibodies against plant viruses

International Nuclear Information System (INIS)

Sandler, E.; Dietzgen, R.G.

1984-01-01

Ever since antigenic properties of plant viruses were discovered antisera have been raised and used for plant virus diagnosis and for the analysis of virus structure as well. From the early qualitative diagnosis method of precipitating the virus in clarified sap of an infected plant and the first quantitative application of the precipitin test vast progress has been made with regard to the development of highly sensitive and highly quantitative methods for virus detection. Of equal importance was the improvement of methods for separating virus from host cell components since the specificity of antisera raised against a virus could be increased by using an antigen for immunization highly concentrated and largely freed from contaminating host substances. The introduction of the enzyme-linked immunosorbent assay (ELISA) into plant virology allows detection of virus in nanogram quantities. Still, the conventionally raised antisera, no matter how pure an antigen was used for immunization, are polyclonal. They contain products of thousands of different antibody-secreting plasma cell clones which can be directed against all antigenic determinants (epitopes) of the virus, but also against antigens of the host plant that may not have been entirely separated from the immunizing virus during the purification procedure. Even after cross adsorption of polyclonal antisera some residual heterogeneity can be expected to remain. Within these boundaries the information gained with polyclonal antisera on virus structure and on virus diagnosis has to be interpreted

Zika Virus and Pregnancy

Science.gov (United States)

... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus ...

Zika Virus

Science.gov (United States)

... with facebook share with twitter share with linkedin Zika Virus Credit: NIAID A female Aedes mosquito. This type of mosquito can transmit Zika, ... transmitted to humans through the bite of infected Aedes aegypti mosquitoes. Zika virus can be transmitted from an infected pregnant woman ...

CHANDIPURA VIRUS

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. CHANDIPURA VIRUS. First isolated from a village called Chandipura near Nagpur in 1965 in India. Belongs to rhabdoviridae family. Used as a Model System to study RNA virus multiplication in the infected cell at molecular level. Notes:

Clinical and biological differences between recurrent herpes simplex virus and varicella-zoster virus infections

International Nuclear Information System (INIS)

Straus, S.E.

1989-01-01

The major features that distinguish recurrent herpes simplex virus infections from zoster are illustrated in this article by two case histories. The clinical and epidemiologic features that characterize recurrent herpes simplex virus and varicella-zoster virus infections are reviewed. It is noted that herpesvirus infections are more common and severe in patients with cellular immune deficiency. Each virus evokes both humoral and cellular immune response in the course of primary infection. DNA hybridization studies with RNA probes labelled with sulfur-35 indicate that herpes simplex viruses persist within neurons, and that varicella-zoster virus is found in the satellite cells that encircle the neurons

Zika Virus and Pregnancy

Medline Plus

Full Text Available ... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your ...

Zika Virus and Pregnancy

Medline Plus

Full Text Available ... Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and ... Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus ...

What's West Nile Virus?

Science.gov (United States)

... for Educators Search English Español What's West Nile Virus? KidsHealth / For Kids / What's West Nile Virus? Print en español ¿Qué es el Virus del Nilo Occidental? What exactly is the West ...

Zika Virus and Pregnancy

Medline Plus

Full Text Available ... Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and Pregnancy Page ... Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus if you ...

A Trusted Portable Computing Device

Science.gov (United States)

Ming-wei, Fang; Jun-jun, Wu; Peng-fei, Yu; Xin-fang, Zhang

A trusted portable computing device and its security mechanism were presented to solve the security issues, such as the attack of virus and Trojan horse, the lost and stolen of storage device, in mobile office. It used smart card to build a trusted portable security base, virtualization to create a secure virtual execution environment, two-factor authentication mechanism to identify legitimate users, and dynamic encryption to protect data privacy. The security environment described in this paper is characteristic of portability, security and reliability. It can meet the security requirement of mobile office.

Human Immunodeficiency Virus and Hepatitis C Virus Co-infection ...

African Journals Online (AJOL)

Human Immunodeficiency Virus and Hepatitis C Virus Co-infection in Cameroon: Investigation of the Genetic Diversity and Virulent ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL · RESOURCES ... DNA sequencing, and bioinformatics tools for sequence management and analysis.

SDT: a virus classification tool based on pairwise sequence alignment and identity calculation.

Directory of Open Access Journals (Sweden)

Brejnev Muhizi Muhire

Full Text Available The perpetually increasing rate at which viral full-genome sequences are being determined is creating a pressing demand for computational tools that will aid the objective classification of these genome sequences. Taxonomic classification approaches that are based on pairwise genetic identity measures are potentially highly automatable and are progressively gaining favour with the International Committee on Taxonomy of Viruses (ICTV. There are, however, various issues with the calculation of such measures that could potentially undermine the accuracy and consistency with which they can be applied to virus classification. Firstly, pairwise sequence identities computed based on multiple sequence alignments rather than on multiple independent pairwise alignments can lead to the deflation of identity scores with increasing dataset sizes. Also, when gap-characters need to be introduced during sequence alignments to account for insertions and deletions, methodological variations in the way that these characters are introduced and handled during pairwise genetic identity calculations can cause high degrees of inconsistency in the way that different methods classify the same sets of sequences. Here we present Sequence Demarcation Tool (SDT, a free user-friendly computer program that aims to provide a robust and highly reproducible means of objectively using pairwise genetic identity calculations to classify any set of nucleotide or amino acid sequences. SDT can produce publication quality pairwise identity plots and colour-coded distance matrices to further aid the classification of sequences according to ICTV approved taxonomic demarcation criteria. Besides a graphical interface version of the program for Windows computers, command-line versions of the program are available for a variety of different operating systems (including a parallel version for cluster computing platforms.

Virus world as an evolutionary network of viruses and capsidless selfish elements.

Science.gov (United States)

Koonin, Eugene V; Dolja, Valerian V

2014-06-01

Viruses were defined as one of the two principal types of organisms in the biosphere, namely, as capsid-encoding organisms in contrast to ribosome-encoding organisms, i.e., all cellular life forms. Structurally similar, apparently homologous capsids are present in a huge variety of icosahedral viruses that infect bacteria, archaea, and eukaryotes. These findings prompted the concept of the capsid as the virus "self" that defines the identity of deep, ancient viral lineages. However, several other widespread viral "hallmark genes" encode key components of the viral replication apparatus (such as polymerases and helicases) and combine with different capsid proteins, given the inherently modular character of viral evolution. Furthermore, diverse, widespread, capsidless selfish genetic elements, such as plasmids and various types of transposons, share hallmark genes with viruses. Viruses appear to have evolved from capsidless selfish elements, and vice versa, on multiple occasions during evolution. At the earliest, precellular stage of life's evolution, capsidless genetic parasites most likely emerged first and subsequently gave rise to different classes of viruses. In this review, we develop the concept of a greater virus world which forms an evolutionary network that is held together by shared conserved genes and includes both bona fide capsid-encoding viruses and different classes of capsidless replicons. Theoretical studies indicate that selfish replicons (genetic parasites) inevitably emerge in any sufficiently complex evolving ensemble of replicators. Therefore, the key signature of the greater virus world is not the presence of a capsid but rather genetic, informational parasitism itself, i.e., various degrees of reliance on the information processing systems of the host. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

The Macroeconomic Impact of Ebola Virus Disease (Evd: A Contribution to the Empirics of Growth

Directory of Open Access Journals (Sweden)

Obukohwo Oba Efayena

2016-04-01

Full Text Available The paper addressed the formulation of a macro model to capture the macroeconomic impact of the Ebola Virus Disease (EVD. Previous studies has adopted various models such as the dynamic computable general equilibrium (CGE model, endogenous model and the LINKAGE model, but there is dire need to generate a step-by-step model which will comprehensively capture how the Ebola Virus Disease (EVD impacts on macroeconomic variables. Adopting the traditional neoclassical growth model, the model aggregated the various macroeconomic variables as well as captured the epidemic’s strain on each of these variables. The paper also empirically shows that the Ebola Virus Disease (EVD has direct, indirect and deferred indirect cost implications for the economy. Using case studies of countries in Africa, the study evaluated how the Ebola Virus Disease (EVD has affected the macroeconomic status of selected economies. The findings imply that there is dire need to control the spread of the deadly plague. The paper contribute immensely to empirical studies in the field of macroeconomics.

Replacement of Murine Leukemia Virus Readthrough Mechanism by Human Immunodeficiency Virus Frameshift Allows Synthesis of Viral Proteins and Virus Replication

Science.gov (United States)

Brunelle, Marie-Noëlle; Brakier-Gingras, Léa; Lemay, Guy

2003-01-01

Retroviruses use unusual recoding strategies to synthesize the Gag-Pol polyprotein precursor of viral enzymes. In human immunodeficiency virus, ribosomes translating full-length viral RNA can shift back by 1 nucleotide at a specific site defined by the presence of both a slippery sequence and a downstream stimulatory element made of an extensive secondary structure. This so-called frameshift mechanism could become a target for the development of novel antiviral strategies. A different recoding strategy is used by other retroviruses, such as murine leukemia viruses, to synthesize the Gag-Pol precursor; in this case, a stop codon is suppressed in a readthrough process, again due to the presence of a specific structure adopted by the mRNA. Development of antiframeshift agents will greatly benefit from the availability of a simple animal and virus model. For this purpose, the murine leukemia virus readthrough region was rendered inactive by mutagenesis and the frameshift region of human immunodeficiency virus was inserted to generate a chimeric provirus. This substitution of readthrough by frameshift allows the synthesis of viral proteins, and the chimeric provirus sequence was found to generate infectious viruses. This system could be a most interesting alternative to study ribosomal frameshift in the context of a virus amenable to the use of a simple animal model. PMID:12584361

[Mumps vaccine virus transmission].

Science.gov (United States)

Otrashevskaia, E V; Kulak, M V; Otrashevskaia, A V; Karpov, I A; Fisenko, E G; Ignat'ev, G M

2013-01-01

In this work we report the mumps vaccine virus shedding based on the laboratory confirmed cases of the mumps virus (MuV) infection. The likely epidemiological sources of the transmitted mumps virus were children who were recently vaccinated with the mumps vaccine containing Leningrad-Zagreb or Leningrad-3 MuV. The etiology of the described cases of the horizontal transmission of both mumps vaccine viruses was confirmed by PCR with the sequential restriction analysis.

Computed tomography in opportunistic lung infections

International Nuclear Information System (INIS)

Hartelius, H.

1988-01-01

Chest radiography in two teenage boys, one with Wiscott-Aldrich's syndrome and one with acute lymphatic leucemia in remission showed increased interstitial pattern. In both computed tomography (CT) of the lungs showed heavy interstitial pneumonia, rather different in appearance but in both cases equal to the CT findings in opportunistic lung infections known from immunoincompetent patients with for instance pneumocystis carinii and/or cytomegalo virus infections. In both patients the CT findings led to lung biopsy establishing the etiologic agent. (orig.)

Zika Virus and Pregnancy

Medline Plus

Full Text Available ... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus ...

Zika Virus Fact Sheet

Science.gov (United States)

... is caused by a virus transmitted primarily by Aedes mosquitoes. People with Zika virus disease can have symptoms including mild fever, skin ... framework. Q&A: Zika virus and complication ... mosquito from the Aedes genus, mainly Aedes aegypti in tropical regions. Aedes ...

An infectious bat-derived chimeric influenza virus harbouring the entry machinery of an influenza A virus.

Science.gov (United States)

Juozapaitis, Mindaugas; Aguiar Moreira, Étori; Mena, Ignacio; Giese, Sebastian; Riegger, David; Pohlmann, Anne; Höper, Dirk; Zimmer, Gert; Beer, Martin; García-Sastre, Adolfo; Schwemmle, Martin

2014-07-23

In 2012, the complete genomic sequence of a new and potentially harmful influenza A-like virus from bats (H17N10) was identified. However, infectious influenza virus was neither isolated from infected bats nor reconstituted, impeding further characterization of this virus. Here we show the generation of an infectious chimeric virus containing six out of the eight bat virus genes, with the remaining two genes encoding the haemagglutinin and neuraminidase proteins of a prototypic influenza A virus. This engineered virus replicates well in a broad range of mammalian cell cultures, human primary airway epithelial cells and mice, but poorly in avian cells and chicken embryos without further adaptation. Importantly, the bat chimeric virus is unable to reassort with other influenza A viruses. Although our data do not exclude the possibility of zoonotic transmission of bat influenza viruses into the human population, they indicate that multiple barriers exist that makes this an unlikely event.

A general method to quantify quasi-equivalence in icosahedral viruses.

Science.gov (United States)

Damodaran, K V; Reddy, Vijay S; Johnson, John E; Brooks, Charles L

2002-12-06

A quantitative, atom-based, method is described for comparing protein subunit interfaces in icosahedral virus capsids with quasi-equivalent surface lattices. An integrated, normalized value (between 0 and 1) based on equivalent residue contacts (Q-score) is computed for every pair of subunit interactions and scores that are significantly above zero readily identify interfaces that are quasi-equivalent to each other. The method was applied to all quasi-equivalent capsid structures (T=3, 4, 7 and 13) in the Protein Data Bank and the Q-scores were interpreted in terms of their structural underpinnings. The analysis allowed classification of T=3 structures into three groups with architectures that resemble different polyhedra with icosahedral symmetry. The preference of subunits to form dimers in the T=4 human Hepatitis B virus capsid (HBV) was clearly reflected in high Q-scores of quasi-equivalent dimers. Interesting differences between the classical T=7 capsid and polyoma-like capsids were also identified. Application of the method to the outer-shell of the T=13 Blue tongue virus core (BTVC) highlighted the modest distortion between the interfaces of the general trimers and the strict trimers of VP7 subunits. Furthermore, the method identified the quasi 2-fold symmetry in the inner capsids of the BTV and reovirus cores. The results show that the Q-scores of various quasi-symmetries represent a "fingerprint" for a particular virus capsid architecture allowing particle classification into groups based on their underlying structural and geometric features.

Basic definitions for discrete modeling of computer worms epidemics

Directory of Open Access Journals (Sweden)

Pedro Guevara López

2015-01-01

Full Text Available The information technologies have evolved in such a way that communication between computers or hosts has become common, so much that the worldwide organization (governments and corporations depends on it; what could happen if these computers stop working for a long time is catastrophic. Unfortunately, networks are attacked by malware such as viruses and worms that could collapse the system. This has served as motivation for the formal study of computer worms and epidemics to develop strategies for prevention and protection; this is why in this paper, before analyzing epidemiological models, a set of formal definitions based on set theory and functions is proposed for describing 21 concepts used in the study of worms. These definitions provide a basis for future qualitative research on the behavior of computer worms, and quantitative for the study of their epidemiological models.

Zika virus infection.

Science.gov (United States)

Pougnet, Laurence; Thill, Chloé; Pougnet, Richard; Auvinet, Henri; Giacardi, Christophe; Drouillard, Isabelle

2016-12-01

A 21-year old woman from New-Caledonia had 40 ̊C fever with vomiting, arthralgia, myalgia, and measles-like rash. Etiological analyses showed primary infection with Zika virus. Because of severe clinical presentation, she was hospitalized in the intensive care unit of the Brest military Hospital. Zika virus is mainly transmitted by Aedes mosquitoes. If they settle in Metropolitan France, Zika virus might also spread there.

Comparative analysis of rabbit hemorrhagic disease virus (RHDV) and new RHDV2 virus antigenicity, using specific virus-like particles.

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Bárcena, Juan; Guerra, Beatriz; Angulo, Iván; González, Julia; Valcárcel, Félix; Mata, Carlos P; Castón, José R; Blanco, Esther; Alejo, Alí

2015-09-24

In 2010 a new Lagovirus related to rabbit haemorrhagic disease virus (RHDV) emerged in France and has since rapidly spread throughout domestic and wild rabbit populations of several European countries. The new virus, termed RHDV2, exhibits distinctive genetic, antigenic and pathogenic features. Notably, RHDV2 kills rabbits previously vaccinated with RHDV vaccines. Here we report for the first time the generation and characterization of RHDV2-specific virus-like particles (VLPs). Our results further confirmed the differential antigenic properties exhibited by RHDV and RHDV2, highlighting the need of using RHDV2-specific diagnostic assays to monitor the spread of this new virus.

Structural and Functional Studies on the Fusion and Attachment Envelope Glycoproteins of Nipah Virus and Hendra Virus

Science.gov (United States)

2003-01-01

including measles virus (MeV), mumps virus, Sendai virus (SeV), Newcastle disease virus (NDV), rinderpest virus, canine distemper virus (CDV), human...Institute of Health, Bethesda, MD. Hut 102, MT2, MT4, and CEM human T cell lines were provided by Chou-Zen Giam, USUHS, Bethesda, MD. The human osteosarcoma

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

DEFF Research Database (Denmark)

Francis, Roy Mathew; Kryger, Per

2012-01-01

A new RT-PCR primer pair designed to identify Acute Bee Paralysis Virus (ABPV), Kashmir Bee Virus (KBV) or Israeli Acute Bee Paralysis Virus (IAPV) of honey bees (Apis mellifera L.) in a single assay is described. These primers are used to screen samples for ABPV, KBV, or IAPV in a single RT-PCR ......-PCR reaction saving time and money. The primers are located in the predicted overlapping gene (pog/ORFX) which is highly conserved across ABPV, KBV, IAPV and other dicistroviruses of social insects. This study has also identified the first case of IAPV in Denmark....

Yeast for virus research

Science.gov (United States)

Zhao, Richard Yuqi

2017-01-01

Budding yeast (Saccharomyces cerevisiae) and fission yeast (Schizosaccharomyces pombe) are two popular model organisms for virus research. They are natural hosts for viruses as they carry their own indigenous viruses. Both yeasts have been used for studies of plant, animal and human viruses. Many positive sense (+) RNA viruses and some DNA viruses replicate with various levels in yeasts, thus allowing study of those viral activities during viral life cycle. Yeasts are single cell eukaryotic organisms. Hence, many of the fundamental cellular functions such as cell cycle regulation or programed cell death are highly conserved from yeasts to higher eukaryotes. Therefore, they are particularly suited to study the impact of those viral activities on related cellular activities during virus-host interactions. Yeasts present many unique advantages in virus research over high eukaryotes. Yeast cells are easy to maintain in the laboratory with relative short doubling time. They are non-biohazardous, genetically amendable with small genomes that permit genome-wide analysis of virologic and cellular functions. In this review, similarities and differences of these two yeasts are described. Studies of virologic activities such as viral translation, viral replication and genome-wide study of virus-cell interactions in yeasts are highlighted. Impacts of viral proteins on basic cellular functions such as cell cycle regulation and programed cell death are discussed. Potential applications of using yeasts as hosts to carry out functional analysis of small viral genome and to develop high throughput drug screening platform for the discovery of antiviral drugs are presented. PMID:29082230

Special Issue: Honey Bee Viruses

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Sebastian Gisder

2015-10-01

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

Special Issue: Honey Bee Viruses

Science.gov (United States)

Gisder, Sebastian; Genersch, Elke

2015-01-01

Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus), or a so far neglected virus species (Apis mellifera filamentous virus), and cutting edge technologies (mass spectrometry, RNAi approach) applied in the field. PMID:26702462

Can genetic algorithms help virus writers reshape their creations and avoid detection?

Science.gov (United States)

Abu Doush, Iyad; Al-Saleh, Mohammed I.

2017-11-01

Different attack and defence techniques have been evolved over time as actions and reactions between black-hat and white-hat communities. Encryption, polymorphism, metamorphism and obfuscation are among the techniques used by the attackers to bypass security controls. On the other hand, pattern matching, algorithmic scanning, emulation and heuristic are used by the defence team. The Antivirus (AV) is a vital security control that is used against a variety of threats. The AV mainly scans data against its database of virus signatures. Basically, it claims a virus if a match is found. This paper seeks to find the minimal possible changes that can be made on the virus so that it will appear normal when scanned by the AV. Brute-force search through all possible changes can be a computationally expensive task. Alternatively, this paper tries to apply a Genetic Algorithm in solving such a problem. Our proposed algorithm is tested on seven different malware instances. The results show that in all the tested malware instances only a small change in each instance was good enough to bypass the AV.

Diversity of viruses in Ixodes ricinus, and characterization of a neurotropic strain of Eyach virus.

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Moutailler, S; Popovici, I; Devillers, E; Vayssier-Taussat, M; Eloit, M

2016-05-01

Ticks transmit more pathogens-including bacteria, parasites and viruses-than any other arthropod vector. Although the epidemiological status of many tick-borne bacteria is very well characterized, tick-borne viruses are still relatively under-studied. Recently, several novel tick-borne viruses have been isolated from human febrile illnesses following tick bites, indicating the existence of other potential new and unknown tick-borne viruses. We used high-throughput sequencing to analyse the virome of Ixodes ricinus, the main vector of tick-borne pathogens in Europe. The majority of collected viral sequences were assigned to two potentially novel Nairovirus and Phlebovirus viruses, with prevalence rates ranging from 3.95% to 23.88% in adults and estimated to be between 0.14% and 72.16% in nymphs. These viruses could not be isolated from the brains of inoculated immunocompromised mice, perhaps indicating that they are unable to infect vertebrates. Within the I. ricinus virome, we also identified contigs with >90% identity to the known Eyach virus. Initially isolated in the 1980s, this virus was indirectly associated with human disease, but had never been extensively studied. Eyach virus prevalence varied between 0.07% and 5.26% in ticks from the French Ardennes and Alsace regions. Eyach virus was successfully isolated following intracerebral inoculation of immunocompromised mice with Eyach virus-positive tick extracts. This virus was also able to multiply and persist in the blood of immunocompetent mice inoculated by intraperitoneal injection, and caused brain infections in three of nine juveniles, without any obvious deleterious effects.

Zika Virus: An Emerging Worldwide Threat

OpenAIRE

Irfan A. Rather; Jameel B. Lone; Vivek K. Bajpai; Woon K. Paek; Jeongheui Lim

2017-01-01

ZIKA virus (ZIKV) poses a severe threat to the world. Recent outbreaks of ZIKV after 2007 along with its quick transmission have made this virus a matter of international concern. The virus shows symptoms that are similar to those caused in the wake of dengue virus (DENV) and other flaviviruses, which makes it difficult to discern the viral infection. Diagnosis is further complicated as the virus cross-reacts with antibodies of other viruses. Currently, molecular diagnosis of the virus is bei...

How hepatitis D virus can hinder the control of hepatitis B virus.

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Maria Xiridou

Full Text Available BACKGROUND: Hepatitis D (or hepatitis delta virus is a defective virus that relies on hepatitis B virus (HBV for transmission; infection with hepatitis D can occur only as coinfection with HBV or superinfection of an existing HBV infection. Because of the bond between the two viruses, control measures for HBV may have also affected the spread of hepatitis D, as evidenced by the decline of hepatitis D in recent years. Since the presence of hepatitis D is associated with suppressed HBV replication and possibly infectivity, it is reasonable to speculate that hepatitis D may facilitate the control of HBV. METHODOLOGY AND PRINCIPAL FINDINGS: We introduced a mathematical model for the transmission of HBV and hepatitis D, where individuals with dual HBV and hepatitis D infection transmit both viruses. We calculated the reproduction numbers of single HBV infections and dual HBV and hepatitis D infections and examined the endemic prevalences of the two viruses. The results show that hepatitis D virus modulates not only the severity of the HBV epidemic, but also the impact of interventions for HBV. Surprisingly we find that the presence of hepatitis D virus may hamper the eradication of HBV. Interventions that aim to reduce the basic reproduction number of HBV below one may not be sufficient to eradicate the virus, as control of HBV depends also on the reproduction numbers of dual infections. CONCLUSIONS AND SIGNIFICANCE: For populations where hepatitis D is endemic, plans for control programs ignoring the presence of hepatitis D may underestimate the HBV epidemic and produce overoptimistic results. The current HBV surveillance should be augmented with monitoring of hepatitis D, in order to improve accuracy of the monitoring and the efficacy of control measures.

Archaeal viruses of the sulfolobales

DEFF Research Database (Denmark)

Erdmann, Susanne; Garrett, Roger Antony

2015-01-01

in CRISPR loci of Sulfolobus species from a second coinfecting conjugative plasmid or virus (Erdmann and Garrett, Mol Microbiol 85:1044-1056, 2012; Erdmann et al. Mol Microbiol 91:900-917, 2014). Here we describe, firstly, the isolation of archaeal virus mixtures from terrestrial hot springs...... with an environmental virus mixture isolated from Yellowstone National Park (Erdmann and Garrett, Mol Microbiol 85:1044-1056, 2012). Experimental studies of isolated genetic elements from this mixture revealed that SMV1 (S ulfolobus Monocauda Virus 1), a tailed spindle-shaped virus, can induce spacer acquisition...... and the techniques used both to infect laboratory strains with these virus mixtures and to obtain purified virus particles. Secondly, we present the experimental conditions required for activating SMV1-induced spacer acquisition in two different Sulfolobus species....

Seasonal and pandemic human influenza viruses attach better to human upper respiratory tract epithelium than avian influenza viruses.

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van Riel, Debby; den Bakker, Michael A; Leijten, Lonneke M E; Chutinimitkul, Salin; Munster, Vincent J; de Wit, Emmie; Rimmelzwaan, Guus F; Fouchier, Ron A M; Osterhaus, Albert D M E; Kuiken, Thijs

2010-04-01

Influenza viruses vary markedly in their efficiency of human-to-human transmission. This variation has been speculated to be determined in part by the tropism of influenza virus for the human upper respiratory tract. To study this tropism, we determined the pattern of virus attachment by virus histochemistry of three human and three avian influenza viruses in human nasal septum, conchae, nasopharynx, paranasal sinuses, and larynx. We found that the human influenza viruses-two seasonal influenza viruses and pandemic H1N1 virus-attached abundantly to ciliated epithelial cells and goblet cells throughout the upper respiratory tract. In contrast, the avian influenza viruses, including the highly pathogenic H5N1 virus, attached only rarely to epithelial cells or goblet cells. Both human and avian viruses attached occasionally to cells of the submucosal glands. The pattern of virus attachment was similar among the different sites of the human upper respiratory tract for each virus tested. We conclude that influenza viruses that are transmitted efficiently among humans attach abundantly to human upper respiratory tract, whereas inefficiently transmitted influenza viruses attach rarely. These results suggest that the ability of an influenza virus to attach to human upper respiratory tract is a critical factor for efficient transmission in the human population.

Primary central nervous system lymphoma in an human immunodeficiency virus-infected patient mimicking bilateral eye sign in brain seen in fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography.

Science.gov (United States)

Kamaleshwaran, Koramadai Karuppusany; Thirugnanam, Rajasekar; Shibu, Deepu; Kalarikal, Radhakrishnan Edathurthy; Shinto, Ajit Sugunan

2014-04-01

Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG PET/CT) has proven useful in the diagnosis, staging, and detection of metastasis and posttreatment monitoring of several malignancies in human immunodeficiency virus (HIV)-infected patients. It also has the ability to make the important distinction between malignancy and infection in the evaluation of central nervous system (CNS) lesions, leading to the initiation of the appropriate treatment and precluding the need for invasive biopsy. We report an interesting case of HIV positive 35-year-old woman presented with headache, disorientation, and decreased level of consciousness. She underwent whole body PET/CT which showed multiple lesions in the cerebrum which mimics bilateral eye in brain. A diagnosis of a primary CNS lymphoma was made and patient was started on chemotherapy.

Primary central nervous system lymphoma in an human immunodeficiency virus-infected patient mimicking bilateral eye sign in brain seen in fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography

International Nuclear Information System (INIS)

Kamaleshwaran, Koramadai Karuppusany; Thirugnanam, Rajasekar; Shibu, Deepu; Kalarikal, Radhakrishnan Edathurthy; Shinto, Ajit Sugunan

2014-01-01

Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG PET/CT) has proven useful in the diagnosis, staging, and detection of metastasis and posttreatment monitoring of several malignancies in human immunodeficiency virus (HIV)-infected patients. It also has the ability to make the important distinction between malignancy and infection in the evaluation of central nervous system (CNS) lesions, leading to the initiation of the appropriate treatment and precluding the need for invasive biopsy. We report an interesting case of HIV positive 35-year-old woman presented with headache, disorientation, and decreased level of consciousness. She underwent whole body PET/CT which showed multiple lesions in the cerebrum which mimics bilateral eye in brain. A diagnosis of a primary CNS lymphoma was made and patient was started on chemotherapy

Mutagenesis-mediated virus extinction: virus-dependent effect of viral load on sensitivity to lethal defection.

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Héctor Moreno

Full Text Available BACKGROUND: Lethal mutagenesis is a transition towards virus extinction mediated by enhanced mutation rates during viral genome replication, and it is currently under investigation as a potential new antiviral strategy. Viral load and virus fitness are known to influence virus extinction. Here we examine the effect or the multiplicity of infection (MOI on progeny production of several RNA viruses under enhanced mutagenesis. RESULTS: The effect of the mutagenic base analogue 5-fluorouracil (FU on the replication of the arenavirus lymphocytic choriomeningitis virus (LCMV can result either in inhibition of progeny production and virus extinction in infections carried out at low multiplicity of infection (MOI, or in a moderate titer decrease without extinction at high MOI. The effect of the MOI is similar for LCMV and vesicular stomatitis virus (VSV, but minimal or absent for the picornaviruses foot-and-mouth disease virus (FMDV and encephalomyocarditis virus (EMCV. The increase in mutation frequency and Shannon entropy (mutant spectrum complexity as a result of virus passage in the presence of FU was more accentuated at low MOI for LCMV and VSV, and at high MOI for FMDV and EMCV. We present an extension of the lethal defection model that agrees with the experimental results. CONCLUSIONS: (i Low infecting load favoured the extinction of negative strand viruses, LCMV or VSV, with an increase of mutant spectrum complexity. (ii This behaviour is not observed in RNA positive strand viruses, FMDV or EMCV. (iii The accumulation of defector genomes may underlie the MOI-dependent behaviour. (iv LCMV coinfections are allowed but superinfection is strongly restricted in BHK-21 cells. (v The dissimilar effects of the MOI on the efficiency of mutagenic-based extinction of different RNA viruses can have implications for the design of antiviral protocols based on lethal mutagenesis, presently under development.

Coinfection of hepatitis E virus and other hepatitis virus in Colombia and its genotypic characterization.

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Peláez, Dioselina; Martínez-Vargas, Daniel; Escalante-Mora, Martha; Palacios-Vivero, Mariel; Contreras-Gómez, Lady

2015-12-04

Hepatitis E virus has emerged as a public health problem, particularly in developing countries. The four genotypes identified in mammals include the G3 found in indigenous hepatitis in countries and regions with high porcine population, and the G1, associated with maternal deaths.  To determine coinfection by hepatitis E virus and the circulating genotypes in Colombia in 1,097 samples using serological markers for hepatitis A, B and C.  Serum samples of 1,097 patients from different regions of Colombia stored at the Laboratorio de Virología of the Instituto Nacional de Salud were selected to detect IgG and IgM anti-hepatitis E virus antibodies. The viral genomes of positive samples were amplified by RT-PCR, and the products were sequenced and phylogenetically analyzed by comparing ORF2 sequences deposited in the GenBank.  IgG anti-hepatitis E virus antibodies were found in 278 samples, IgM in 62, and both markers in 64. Hepatitis E virus and hepatitis A virus coinfection determined by IgG anti-hepatitis E virus was 33.6% and 16.1% by IgM; hepatitis E virus and hepatitis B virus coinfection was 23.4% and 8.1%, and hepatitis E virus and hepatitis C virus coinfection was 35.4% and 5.83%, respectively. Among the 52 positive samples by PCR nine were sequenced and grouped within genotype 3A of the American porcine strain.  The highest seropositivity was observed for hepatitis A and E. The incidence of hepatitis E virus coinfection with other hepatotropic viruses indicated that this pathogen is more frequent than expected. The circulation of genotype 3A implies that this disease may occur in outbreaks and as zoonosis in Colombia.

Comparative Pathology of Hepatitis A Virus and Hepatitis E Virus Infection.

Science.gov (United States)

Cullen, John M; Lemon, Stanley M

2018-04-30

Hepatitis A virus (HAV) and hepatitis E virus (HEV) cause acute, self-limiting hepatic infections that are usually spread by the fecal-oral route in humans. Naturally occurring and experimental infections are possible in a variety of nonhuman primates and, in the case of HEV, a number of other species. Many advances in understanding the pathogenesis of these viruses have come from studies in experimental animals. In general, animals infected with these viruses recapitulate the histologic lesions seen in infected humans, but typically with less severe clinical and histopathological manifestations. This review describes the histopathologic changes associated with HAV and HEV infection in humans and experimental animals. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

[Zika virus infection during pregnancy].

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

2016-05-01

A Zika virus epidemic is currently ongoing in the Americas. This virus is linked to congenital infections with potential severe neurodevelopmental dysfunction. However, incidence of fetal infection and whether this virus is responsible of other fetal complications are still unknown. National and international public health authorities recommend caution and several prevention measures. Declaration of Zika virus infection is now mandatory in France. Given the available knowledge on Zika virus, we suggest here a review of the current recommendations for management of pregnancy in case of suspicious or infection by Zika virus in a pregnant woman. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Human immunodeficiency virus and hepatitus B virus co-infection ...

African Journals Online (AJOL)

Human immunodeficiency virus and hepatitus B virus co-infection amog patients in Kano Nigeria. EE Nwokedi, MA Emokpae, AI Dutse. Abstract. No Abstract. Nigerian Journal of Medicine Vol. 15(3) July-September 2006: 227-229. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD ...

Vaccination with Recombinant Parainfluenza Virus 5 Expressing Neuraminidase Protects against Homologous and Heterologous Influenza Virus Challenge.

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Mooney, Alaina J; Gabbard, Jon D; Li, Zhuo; Dlugolenski, Daniel A; Johnson, Scott K; Tripp, Ralph A; He, Biao; Tompkins, S Mark

2017-12-01

Seasonal human influenza virus continues to cause morbidity and mortality annually, and highly pathogenic avian influenza (HPAI) viruses along with other emerging influenza viruses continue to pose pandemic threats. Vaccination is considered the most effective measure for controlling influenza; however, current strategies rely on a precise vaccine match with currently circulating virus strains for efficacy, requiring constant surveillance and regular development of matched vaccines. Current vaccines focus on eliciting specific antibody responses against the hemagglutinin (HA) surface glycoprotein; however, the diversity of HAs across species and antigenic drift of circulating strains enable the evasion of virus-inhibiting antibody responses, resulting in vaccine failure. The neuraminidase (NA) surface glycoprotein, while diverse, has a conserved enzymatic site and presents an appealing target for priming broadly effective antibody responses. Here we show that vaccination with parainfluenza virus 5 (PIV5), a promising live viral vector expressing NA from avian (H5N1) or pandemic (H1N1) influenza virus, elicited NA-specific antibody and T cell responses, which conferred protection against homologous and heterologous influenza virus challenges. Vaccination with PIV5-N1 NA provided cross-protection against challenge with a heterosubtypic (H3N2) virus. Experiments using antibody transfer indicate that antibodies to NA have an important role in protection. These findings indicate that PIV5 expressing NA may be effective as a broadly protective vaccine against seasonal influenza and emerging pandemic threats. IMPORTANCE Seasonal influenza viruses cause considerable morbidity and mortality annually, while emerging viruses pose potential pandemic threats. Currently licensed influenza virus vaccines rely on the antigenic match of hemagglutinin (HA) for vaccine strain selection, and most vaccines rely on HA inhibition titers to determine efficacy, despite the growing

Influenza A virus targets a cGAS-independent STING pathway that controls enveloped RNA viruses.

Science.gov (United States)

Holm, Christian K; Rahbek, Stine H; Gad, Hans Henrik; Bak, Rasmus O; Jakobsen, Martin R; Jiang, Zhaozaho; Hansen, Anne Louise; Jensen, Simon K; Sun, Chenglong; Thomsen, Martin K; Laustsen, Anders; Nielsen, Camilla G; Severinsen, Kasper; Xiong, Yingluo; Burdette, Dara L; Hornung, Veit; Lebbink, Robert Jan; Duch, Mogens; Fitzgerald, Katherine A; Bahrami, Shervin; Mikkelsen, Jakob Giehm; Hartmann, Rune; Paludan, Søren R

2016-02-19

Stimulator of interferon genes (STING) is known be involved in control of DNA viruses but has an unexplored role in control of RNA viruses. During infection with DNA viruses STING is activated downstream of cGAMP synthase (cGAS) to induce type I interferon. Here we identify a STING-dependent, cGAS-independent pathway important for full interferon production and antiviral control of enveloped RNA viruses, including influenza A virus (IAV). Further, IAV interacts with STING through its conserved hemagglutinin fusion peptide (FP). Interestingly, FP antagonizes interferon production induced by membrane fusion or IAV but not by cGAMP or DNA. Similar to the enveloped RNA viruses, membrane fusion stimulates interferon production in a STING-dependent but cGAS-independent manner. Abolishment of this pathway led to reduced interferon production and impaired control of enveloped RNA viruses. Thus, enveloped RNA viruses stimulate a cGAS-independent STING pathway, which is targeted by IAV.

Enhanced light microscopy visualization of virus particles from Zika virus to filamentous ebolaviruses.

Directory of Open Access Journals (Sweden)

George G Daaboul

Full Text Available Light microscopy is a powerful tool in the detection and analysis of parasites, fungi, and prokaryotes, but has been challenging to use for the detection of individual virus particles. Unlabeled virus particles are too small to be visualized using standard visible light microscopy. Characterization of virus particles is typically performed using higher resolution approaches such as electron microscopy or atomic force microscopy. These approaches require purification of virions away from their normal millieu, requiring significant levels of expertise, and can only enumerate small numbers of particles per field of view. Here, we utilize a visible light imaging approach called Single Particle Interferometric Reflectance Imaging Sensor (SP-IRIS that allows automated counting and sizing of thousands of individual virions. Virions are captured directly from complex solutions onto a silicon chip and then detected using a reflectance interference imaging modality. We show that the use of different imaging wavelengths allows the visualization of a multitude of virus particles. Using Violet/UV illumination, the SP-IRIS technique is able to detect individual flavivirus particles (~40 nm, while green light illumination is capable of identifying and discriminating between vesicular stomatitis virus and vaccinia virus (~360 nm. Strikingly, the technology allows the clear identification of filamentous infectious ebolavirus particles and virus-like particles. The ability to differentiate and quantify unlabeled virus particles extends the usefulness of traditional light microscopy and can be embodied in a straightforward benchtop approach allowing widespread applications ranging from rapid detection in biological fluids to analysis of virus-like particles for vaccine development and production.

Cowpea viruses: Effect of single and mixed infections on symptomatology and virus concentration

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Nsa Imade Y

2007-09-01

Full Text Available Abstract Natural multiple viral infections of cultivated cowpeas have been reported in Nigeria. In this study, three Nigerian commercial cowpea cultivars ("Olo 11", "Oloyin" and "White" and two lines from the IITA (IT86D- 719 and TVU 76 were mechanically inoculated with Cowpea aphid-borne mosaic virus (CABMV, Bean southern mosaic virus (SBMV and Cowpea mottle virus (CMeV singly, as well as in all possible combinations at 10, 20 and 30 days after planting (DAP. Samples of leaves or stems were collected at 10, 20 and 30 days after inoculation (DAI and analyzed for relative virus concentration by Enzyme-Linked Immunosrbent Assay. All the cultivars and lines {CVS/L} were susceptible to the viruses but the commercial CVS showed more severe symptoms and had relatively higher viral concentration. In single virus infections, CABMV which induced the most severe symptoms had absorbance values (at 405 nm of 0.11 to 0.46 while SBMV and CMeV which induced moderate symptoms had virus titre of 0.74 to 1.99 and 0.11 to 0.90 respectively. Plants inoculated 10 DAP had significantly higher virus concentration than those inoculated 30 DAP. In mixed infections involving CABMV (10 DAP apical necrosis and death were observed in commercial cultivars "Olo 11" and "White". Enhancement of CMeV titers were observed in plants infected with CMeV + CABMV. Multiple viral infections of cowpeas may result in complete yield loss, hence, the availability of seeds of cultivars with a high level of multiple virus resistance is recommended as a means of control.

Genome Sequence of Bivens Arm Virus, a Tibrovirus Belonging to the Species Tibrogargan virus (Mononegavirales: Rhabdoviridae).

Science.gov (United States)

Lauck, Michael; Yú, Shu Qìng; Caì, Yíngyún; Hensley, Lisa E; Chiu, Charles Y; O'Connor, David H; Kuhn, Jens H

2015-03-19

The new rhabdoviral genus Tibrovirus currently has two members, Coastal Plains virus and Tibrogargan virus. Here, we report the coding-complete genome sequence of a putative member of this genus, Bivens Arm virus. A genomic comparison reveals Bivens Arm virus to be closely related to, but distinct from, Tibrogargan virus. Copyright © 2015 Lauck et al.

Replication and clearance of respiratory syncytial virus - Apoptosis is an important pathway of virus clearance after experimental infection with bovine respiratory syncytial virus

DEFF Research Database (Denmark)

Viuff, B.; Tjørnehøj, Kirsten; Larsen, Lars Erik

2002-01-01

and clearance in a natural target animal. Replication of BRSV was demonstrated in the luminal part of the respiratory epithelial cells and replication in the upper respiratory tract preceded the replication in the lower respiratory tract. Virus excreted to the lumen of the respiratory tract was cleared...... and the infections with human respiratory syncytial. virus and BRSV have similar clinical, pathological, and epidemiological characteristics. In this study we used experimental BRSV infection in calves as a model of respiratory syncytial virus infection to demonstrate important aspects of viral replication......Human respiratory syncytial virus is an important cause of severe respiratory disease in young children, the elderly, and in immunocompromised adults. Similarly, bovine respiratory syncytial virus (BRSV) is causing severe, sometimes fatal, respiratory disease in calves. Both viruses are pneumovirus...

Temporal Analysis of Andes Virus and Sin Nombre Virus Infections of Syrian Hamsters

Science.gov (United States)

2007-05-01

Microbiology . All Rights Reserved. Temporal Analysis of Andes Virus and Sin Nombre Virus Infections of Syrian Hamsters Victoria Wahl-Jensen,1 Jennifer...Ye, C., J. Prescott , R. Nofchissey, D. Goade, and B. Hjelle. 2004. Neutralizing antibodies and Sin Nombre virus RNA after recovery from hantavirus

Monitoring virus entry into living cells using DiD-labeled dengue virus particles

NARCIS (Netherlands)

Ayala Nunez, Vanesa; Wilschut, Jan; Smit, Jolanda M.

2011-01-01

A variety of approaches can be applied to investigate the multiple steps and interactions that occur during virus entry into the host cell. Single-virus tracking is a powerful real-time imaging technique that offers the possibility to monitor virus-cell binding, internalization, intracellular

Neutralizing antibodies against flaviviruses, Babanki virus, and Rift Valley fever virus in Ugandan bats.

Science.gov (United States)

Kading, Rebekah C; Kityo, Robert M; Mossel, Eric C; Borland, Erin M; Nakayiki, Teddie; Nalikka, Betty; Nyakarahuka, Luke; Ledermann, Jeremy P; Panella, Nicholas A; Gilbert, Amy T; Crabtree, Mary B; Peterhans, Julian Kerbis; Towner, Jonathan S; Amman, Brian R; Sealy, Tara K; Nichol, Stuart T; Powers, Ann M; Lutwama, Julius J; Miller, Barry R

2018-01-01

Introduction: A number of arboviruses have previously been isolated from naturally-infected East African bats, however the role of bats in arbovirus maintenance is poorly understood. The aim of this study was to investigate the exposure history of Ugandan bats to a panel of arboviruses. Materials and methods: Insectivorous and fruit bats were captured from multiple locations throughout Uganda during 2009 and 2011-2013. All serum samples were tested for neutralizing antibodies against West Nile virus (WNV), yellow fever virus (YFV), dengue 2 virus (DENV-2), Zika virus (ZIKV), Babanki virus (BBKV), and Rift Valley fever virus (RVFV) by plaque reduction neutralization test (PRNT). Sera from up to 626 bats were screened for antibodies against each virus. Results and Discussion:  Key findings include the presence of neutralizing antibodies against RVFV in 5/52 (9.6%) of little epauletted fruit bats ( Epomophorus labiatus ) captured from Kawuku and 3/54 (5.6%) Egyptian rousette bats from Kasokero cave. Antibodies reactive to flaviviruses were widespread across bat taxa and sampling locations. Conclusion: The data presented demonstrate the widespread exposure of bats in Uganda to arboviruses, and highlight particular virus-bat associations that warrant further investigation.

Seasonal Dynamics of Haptophytes and dsDNA Algal Viruses Suggest Complex Virus-Host Relationship.

Science.gov (United States)

Johannessen, Torill Vik; Larsen, Aud; Bratbak, Gunnar; Pagarete, António; Edvardsen, Bente; Egge, Elianne D; Sandaa, Ruth-Anne

2017-04-20

Viruses influence the ecology and diversity of phytoplankton in the ocean. Most studies of phytoplankton host-virus interactions have focused on bloom-forming species like Emiliania huxleyi or Phaeocystis spp. The role of viruses infecting phytoplankton that do not form conspicuous blooms have received less attention. Here we explore the dynamics of phytoplankton and algal viruses over several sequential seasons, with a focus on the ubiquitous and diverse phytoplankton division Haptophyta, and their double-stranded DNA viruses, potentially with the capacity to infect the haptophytes. Viral and phytoplankton abundance and diversity showed recurrent seasonal changes, mainly explained by hydrographic conditions. By 454 tag-sequencing we revealed 93 unique haptophyte operational taxonomic units (OTUs), with seasonal changes in abundance. Sixty-one unique viral OTUs, representing Megaviridae and Phycodnaviridae , showed only distant relationship with currently isolated algal viruses. Haptophyte and virus community composition and diversity varied substantially throughout the year, but in an uncoordinated manner. A minority of the viral OTUs were highly abundant at specific time-points, indicating a boom-bust relationship with their host. Most of the viral OTUs were very persistent, which may represent viruses that coexist with their hosts, or able to exploit several host species.

Reference gene selection for quantitative real-time PCR analysis in virus infected cells: SARS corona virus, Yellow fever virus, Human Herpesvirus-6, Camelpox virus and Cytomegalovirus infections

Directory of Open Access Journals (Sweden)

Müller Marcel A

2005-02-01

Full Text Available Abstract Ten potential reference genes were compared for their use in experiments investigating cellular mRNA expression of virus infected cells. Human cell lines were infected with Cytomegalovirus, Human Herpesvirus-6, Camelpox virus, SARS coronavirus or Yellow fever virus. The expression levels of these genes and the viral replication were determined by real-time PCR. Genes were ranked by the BestKeeper tool, the GeNorm tool and by criteria we reported previously. Ranking lists of the genes tested were tool dependent. However, over all, β-actin is an unsuitable as reference gene, whereas TATA-Box binding protein and peptidyl-prolyl-isomerase A are stable reference genes for expression studies in virus infected cells.

Devir vírus Virus devir

Directory of Open Access Journals (Sweden)

Marcos Adegas de Azambuja

2007-12-01

Full Text Available Este trabalho parte dos encontros no Programa de Educação a Distância (EAD da PUCRS Virtual. Objetivamos problematizar como a perspectiva de espaço-tempo, tensionada pelas Tecnologias da Informação e da Comunicação reverbera na produção da subjetividade através da prática educativa em EAD. Traçamos as amarras produzidas por modulação, atualizado na avaliação e formação permanente, constituição de uma subjetividade programada. Perguntamo-nos pelas linhas que afetam as estruturas em formação. É a tecnologia que traz em si as problematizações: vírus nos computadores. Em um devir vírus invadimos os modos de ser, corrompendo as programações. Um vírus não pede licença, afirma sua existência.This work results from the Program of Distance Education (DE hold at PUCRS Virtual. Our purpose is to problematize how understandings of space-time inspired by Information Technology and its effects are expressed in the production of subjectivities as result of DE practices. We'll discuss the movement produced by the modulation process, which is renewed in the extended evaluation, as a programmed subjectivity. We'll problematize ways the lines that affect born structures. The technology itself brings in its creation our problematizations: the computer viruses. It is because of a devir virus we infect ways of being and we brake the programming. A virus lives to affirm its existence.

Filovirus pathogenesis and immune evasion: insights from Ebola virus and Marburg virus

Energy Technology Data Exchange (ETDEWEB)

Messaoudi, Ilhem; Amarasinghe, Gaya K.; Basler, Christopher F.

2015-10-06

Ebola viruses and Marburg viruses, members of the filovirus family, are zoonotic pathogens that cause severe disease in people, as highlighted by the latest Ebola virus epidemic in West Africa. Filovirus disease is characterized by uncontrolled virus replication and the activation of host responses that contribute to pathogenesis. Underlying these phenomena is the potent suppression of host innate antiviral responses, particularly the type I interferon response, by viral proteins, which allows high levels of viral replication. In this Review, we describe the mechanisms used by filoviruses to block host innate immunity and discuss the links between immune evasion and filovirus pathogenesis.

PREFACE The physics of virus assembly The physics of virus assembly

Science.gov (United States)

Stockley, Peter G.; Twarock, Reidun

2010-12-01

Viruses are pathogens in every kingdom of life and are major causes of human disease and suffering. They are known to encompass a size range that overlaps with that of the smallest bacterial cells, and the largest viruses now seem to be hosts of their own viral pathogens. Recent genomic sequencing efforts show that many organisms have genes that are likely to be descended in evolution from viral progenitors. Even more astonishingly, analysis of the world's oceans has shown that some of the simplest viruses, the tailed dsDNA phages, are the most common biological entities on the planet, with estimates of their numbers ranging up to 1031, with ~ 1021 infection events every second, leading to a turnover of around 20% of the biomass in the sea every few days. These cycles of infection and lysis of oceanic bacteria and algae provide the nutrients for the smallest organisms lying at the bottom of the food chain. Without viruses, therefore, life on Earth would probably not be sustainable. These are remarkable facts for systems that are non-living in the strict sense, and are composed of simple materials—nucleic acids, proteins and lipids. Many viruses consist of little more than a protective protein coat surrounding their genomic nucleic acids, which can be either DNA or RNA. Their simplicity leads to highly symmetrical structures with protein containers based on helical or icosahedral lattices. Many simple viruses self-assemble rapidly and with great fidelity, and many groups are busy trying to exploit these properties to make virus-like particles for a wide range of applications, including targeted drug-delivery, medical imaging and even novel materials. This issue of Physical Biology contains a series of papers describing some of the latest experimental and theoretical research on viruses, their structures and assembly, as well as their regulated disassembly during infection. These range from a dissection of the in vivo assembly mechanism of a filamentous virus

Presence and Distribution of Oilseed Pumpkin Viruses and Molecular Detection of Zucchini Yellow Mosaic Virus

Directory of Open Access Journals (Sweden)

Ana Vučurović

2009-01-01

Full Text Available Over the past decade, intensive spread of virus infections of oilseed pumpkin has resulted in significant economic losses in pumpkin crop production, which is currently expanding in our country. In 2007 and 2008, a survey for the presence and distribution of oilseed pumpkin viruses was carried out in order to identify viruses responsible for epidemics and incidences of very destructive symptoms on cucurbit leaves and fruits. Monitoring andcollecting samples of oil pumpkin, as well as other species such as winter and butternut squash and buffalo and bottle gourd with viral infection symptoms, was conducted in several localities of Vojvodina Province. The collected plant samples were tested by DAS-ELISA using polyclonal antisera specific for the detection of six most economically harmful pumpkin viruses: Cucumber mosaic virus (CMV, Zucchini yellow mosaic virus (ZYMV, Watermelon mosaic virus (WMW, Squash mosaic virus (SqMV, Papaya ringspot virus (PRSV and Tobaccoringspot virus (TRSV that are included in A1 quarantine list of harmful organisms in Serbia.Identification of viruses in the collected samples indicated the presence of three viruses, ZYMV, WMV and CMV, in individual and mixed infections. Frequency of the identified viruses varied depending on locality and year of investigations. In 2007, WMV was the most frequent virus (94.2%, while ZYMV was prevalent (98.04% in 2008. High frequency of ZYMV determined in both years of investigation indicated the need for its rapid and reliable molecular detection. During this investigation, a protocol for ZYMVdetection was developed and optimized using specific primers CPfwd/Cprev and commercial kits for total RNA extraction, as well as for RT-PCR. In RT-PCR reaction using these primers, a DNA fragment of approximately 1100 bp, which included coat protein gene, was amplified in the samples of infected pumkin leaves. Although serological methods are still useful for large-scale testing of a great number of

Archaeal virus-host interactions

NARCIS (Netherlands)

Quax, T.E.F.

2013-01-01

The work presented in this thesis provides novel insights in several aspects of the molecular

biology of archaea, bacteria and their viruses.

Three fundamentally different groups of viruses are associated with the three domains of life.

Archaeal viruses are

Prevalence of hepatitis A virus, hepatitis B virus, hepatitis C virus, hepatitis D virus and hepatitis E virus as causes of acute viral hepatitis in North India: a hospital based study.

Science.gov (United States)

Jain, P; Prakash, S; Gupta, S; Singh, K P; Shrivastava, S; Singh, D D; Singh, J; Jain, A

2013-01-01

Acute viral hepatitis (AVH) is a major public health problem and is an important cause of morbidity and mortality. The aim of the present study is to determine the prevalence of hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and hepatitis E virus (HEV) as causes of AVH in a tertiary care hospital of North India. Blood samples and clinical information was collected from cases of AVH referred to the Grade I viral diagnostic laboratory over a 1-year period. Samples were tested for hepatitis B surface antigen, anti-HCV total antibodies, anti-HAV immunoglobulin M (IgM) and anti-HEV IgM by the enzyme-linked immunosorbent assay. PCR for nucleic acid detection of HBV and HCV was also carried out. Those positive for HBV infection were tested for anti-HDV antibodies. Fisher's exact test was used and a P hepatitis cases, 62 (23.22%) patients presented as acute hepatic failure. HAV (26.96%) was identified as the most common cause of acute hepatitis followed by HEV (17.97%), HBV (16.10%) and HCV (11.98%). Co-infections with more than one virus were present in 34 cases; HAV-HEV co-infection being the most common. HEV was the most important cause of acute hepatic failure followed by co-infection with HAV and HEV. An indication towards epidemiological shift of HAV infection from children to adults with a rise in HAV prevalence was seen. To the best of our knowledge, this is the first report indicating epidemiological shift of HAV in Uttar Pradesh.

Epstein-Barr virus, human papillomavirus and mouse mammary tumour virus as multiple viruses in breast cancer.

Science.gov (United States)

Glenn, Wendy K; Heng, Benjamin; Delprado, Warick; Iacopetta, Barry; Whitaker, Noel J; Lawson, James S

2012-01-01

The purpose of this investigation is to determine if Epstein Barr virus (EBV), high risk human papillomavirus (HPV), and mouse mammary tumour viruses (MMTV) co-exist in some breast cancers. All the specimens were from women residing in Australia. For investigations based on standard PCR, we used fresh frozen DNA extracts from 50 unselected invasive breast cancers. For normal breast specimens, we used DNA extracts from epithelial cells from milk donated by 40 lactating women. For investigations based on in situ PCR we used 27 unselected archival formalin fixed breast cancer specimens and 18 unselected archival formalin fixed normal breast specimens from women who had breast reduction surgery. Thirteen of these fixed breast cancer specimens were ductal carcinoma in situ (dcis) and 14 were predominantly invasive ductal carcinomas (idc). EBV sequences were identified in 68%, high risk HPV sequences in 50%, and MMTV sequences in 78% of DNA extracted from 50 invasive breast cancer specimens. These same viruses were identified in selected normal and breast cancer specimens by in situ PCR. Sequences from more than one viral type were identified in 72% of the same breast cancer specimens. Normal controls showed these viruses were also present in epithelial cells in human milk - EBV (35%), HPV, 20%) and MMTV (32%) of 40 milk samples from normal lactating women, with multiple viruses being identified in 13% of the same milk samples. We conclude that (i) EBV, HPV and MMTV gene sequences are present and co-exist in many human breast cancers, (ii) the presence of these viruses in breast cancer is associated with young age of diagnosis and possibly an increased grade of breast cancer.

Inhibition of Interferon Induction and Action by the Nairovirus Nairobi Sheep Disease Virus/Ganjam Virus

OpenAIRE

Holzer, Barbara; Bakshi, Siddharth; Bridgen, Anne; Baron, Michael D.

2011-01-01

The Nairoviruses are an important group of tick-borne viruses that includes pathogens of man (Crimean Congo hemorrhagic fever virus) and livestock animals (Dugbe virus, Nairobi sheep disease virus (NSDV)). NSDV is found in large parts of East Africa and the Indian subcontinent (where it is known as Ganjam virus). We have investigated the ability of NSDV to antagonise the induction and actions of interferon. Both pathogenic and apathogenic isolates could actively inhibit the induction of type ...

Characterization of Ebola Virus Entry by Using Pseudotyped Viruses: Identification of Receptor-Deficient Cell Lines

OpenAIRE

Wool-Lewis, Rouven J.; Bates, Paul

1998-01-01

Studies analyzing Ebola virus replication have been severely hampered by the extreme pathogenicity of this virus. To permit analysis of the host range and function of the Ebola virus glycoprotein (Ebo-GP), we have developed a system for pseudotyping these glycoproteins into murine leukemia virus (MLV). This pseudotyped virus, MLV(Ebola), can be readily concentrated to titers which exceed 5 × 106 infectious units/ml and is effectively neutralized by antibodies specific for Ebo-GP. Analysis of ...

Das Epstein-Barr-Virus ( = Epstein-Barr virus)

OpenAIRE

Niller, H. H.; Wolf, Hans J.

1993-01-01

Epstein-Barr virus is an ubiquitous humanpathogenic herpesvirus. It has been identified as the etiologic agent of infectious mononucleosis. In addition it is associated with the cancers nasopharyngeal carcinoma and Burkitt's lymphoma. Like other herpesviruses it infects cells in a lytic way or it persists in a latent state. Classically, the serologic diagnosis of Epstein-Barr virus infections is done by the agglutination of sheep erythrocytes according to Paul and Bunnell as a rapid testing m...

[Viruses and civilization].

Science.gov (United States)

Chastel, C

1999-01-01

A few million years ago, when primates moved from the east African forest to the savannah, they were already infected with endogenous viruses and occultly transmitted them to the prime Homo species. However it was much later with the building of the first large cities in Mesopotamia that interhuman viral transmission began in earnest. Spreading was further enhanced with the organization of the Egyptian, Greek, Roman, and Arab empires around the Mediterranean. Discovery of the New World in 1492 led to an unprecedented clash of civilizations and the destruction of pre-Columbian Indian civilizations. It also led to a rapid spread of viruses across the Atlantic Ocean with the emergence of yellow fever and appearance of smallpox and measles throughout the world. However the greatest opportunities for worldwide viral development have been created by our present, modern civilization. This fact is illustrated by epidemic outbreaks of human immunodeficiency virus, Venezuela hemorrhagic fever, Rift valley fever virus, and monkey pox virus. Close analysis underscores the major role of human intervention in producing these events.

Comparative analysis of rabbit hemorrhagic disease virus (RHDV) and new RHDV2 virus antigenicity, using specific virus-like particles

OpenAIRE

Bárcena, Juan; Guerra, Beatriz; Angulo, Iván; González, Julia; Valcárcel, Félix; Mata, Carlos P.; Castón, José R.; Blanco, Esther; Alejo, Alí

2015-01-01

International audience; In 2010 a new Lagovirus related to rabbit haemorrhagic disease virus (RHDV) emerged in France and has since rapidly spread throughout domestic and wild rabbit populations of several European countries. The new virus, termed RHDV2, exhibits distinctive genetic, antigenic and pathogenic features. Notably, RHDV2 kills rabbits previously vaccinated with RHDV vaccines. Here we report for the first time the generation and characterization of RHDV2-specific virus-like particl...

RECOVIR Software for Identifying Viruses

Science.gov (United States)

Chakravarty, Sugoto; Fox, George E.; Zhu, Dianhui

2013-01-01

Most single-stranded RNA (ssRNA) viruses mutate rapidly to generate a large number of strains with highly divergent capsid sequences. Determining the capsid residues or nucleotides that uniquely characterize these strains is critical in understanding the strain diversity of these viruses. RECOVIR (an acronym for "recognize viruses") software predicts the strains of some ssRNA viruses from their limited sequence data. Novel phylogenetic-tree-based databases of protein or nucleic acid residues that uniquely characterize these virus strains are created. Strains of input virus sequences (partial or complete) are predicted through residue-wise comparisons with the databases. RECOVIR uses unique characterizing residues to identify automatically strains of partial or complete capsid sequences of picorna and caliciviruses, two of the most highly diverse ssRNA virus families. Partition-wise comparisons of the database residues with the corresponding residues of more than 300 complete and partial sequences of these viruses resulted in correct strain identification for all of these sequences. This study shows the feasibility of creating databases of hitherto unknown residues uniquely characterizing the capsid sequences of two of the most highly divergent ssRNA virus families. These databases enable automated strain identification from partial or complete capsid sequences of these human and animal pathogens.

Hepatitis virus panel

Science.gov (United States)

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

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

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manon edekeyser

2015-06-01

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

Outbreaks of influenza A virus in farmed mink (Neovison vison) in Denmark: molecular characterization of the viruses

DEFF Research Database (Denmark)

Larsen, Lars Erik; Breum, Solvej Østergaard; Trebbien, Ramona

2012-01-01

that the virus was a human/swine reassortant, with the H and N gene most related to human H3N2 viruses circulating in 2005. The remaining 6 genes were most closely related to H1N2 influenza viruses circulating in Danish swine. This virus had not previously been described in swine, mink or humans. PCRs assays...... specifically targeting the new reassortant were developed and used to screen influenza positive samples from humans and swine in Denmark with negative results. Thus, there was no evidence that this virus had spread to humans or was circulating in Danish pigs. In 2010 and 2011, influenza virus was again...... diagnosed in diseased mink in a few farms. The genetic typing showed that the virus was similar to the pandemic H1N1 virus circulating in humans and swine. The H3N2 virus was not detected in 2010 and 2011. Taken together, these findings indicate that mink is highly susceptible for influenza A virus of human...

Diversity of viruses in Ixodes ricinus, and characterization of a neurotropic strain of Eyach virus

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S. Moutailler

2016-05-01

Full Text Available Ticks transmit more pathogens—including bacteria, parasites and viruses—than any other arthropod vector. Although the epidemiological status of many tick-borne bacteria is very well characterized, tick-borne viruses are still relatively under-studied. Recently, several novel tick-borne viruses have been isolated from human febrile illnesses following tick bites, indicating the existence of other potential new and unknown tick-borne viruses. We used high-throughput sequencing to analyse the virome of Ixodes ricinus, the main vector of tick-borne pathogens in Europe. The majority of collected viral sequences were assigned to two potentially novel Nairovirus and Phlebovirus viruses, with prevalence rates ranging from 3.95% to 23.88% in adults and estimated to be between 0.14% and 72.16% in nymphs. These viruses could not be isolated from the brains of inoculated immunocompromised mice, perhaps indicating that they are unable to infect vertebrates. Within the I. ricinus virome, we also identified contigs with >90% identity to the known Eyach virus. Initially isolated in the 1980s, this virus was indirectly associated with human disease, but had never been extensively studied. Eyach virus prevalence varied between 0.07% and 5.26% in ticks from the French Ardennes and Alsace regions. Eyach virus was successfully isolated following intracerebral inoculation of immunocompromised mice with Eyach virus-positive tick extracts. This virus was also able to multiply and persist in the blood of immunocompetent mice inoculated by intraperitoneal injection, and caused brain infections in three of nine juveniles, without any obvious deleterious effects.

Analysis of proteins of mouse sarcoma pseudotype viruses: type-specific radioimmunoassays for ecotropic virus p30's

International Nuclear Information System (INIS)

Kennel, S.J.; Tennant, R.W.

1979-01-01

Murine sarcoma virus pseudotypes were prepared by infection of nonproducer cells (A1-2), which were transformed by the Gazdar strain of mouse sarcoma virus, with Gross (N-tropic), WN1802B (B-tropic), or Moloney (NB-tropic) viruses. The respective host range pseudotype sarcoma viruses were defined by the tritration characteristics on cells with the appropriate Fv-1 genotype. Proteins from virus progeny were analyzed by sodium dodecyl sulfate--polyacrylamide gel electrophoresis. Bands present in both the 65,000- and the 10,000- to 20,000-molecular-weight regions of the gel distinguished the pseudotype viruses from their respective helpers. Furthermore, two protein bands were noted in the p30 region of murine sarcoma virus (Gross), one corresponding to Gross virus p30, and another of slightly slower mobility. However, since the mobility of the putative sarcoma p30 is nearly indentical to that of WN1802B, its presence could not be established by sodium dodecyl sulfate--polyacrylamide gel electrophoresis. Type-specific radioimmunossays for Gross virus p30 and for WN1802B p30 were applied for analysis of pseudotype preparations, and among several ecotropic viruses tested, only the homologous virus scored in the respective assay. By use of these assays, pseudotype viruses were found to contain only 8 to 48% helper-specific p30's; the remainder is presumably derived from the sarcoma virus

Bioinformatics Meets Virology: The European Virus Bioinformatics Center's Second Annual Meeting.

Science.gov (United States)

Ibrahim, Bashar; Arkhipova, Ksenia; Andeweg, Arno C; Posada-Céspedes, Susana; Enault, François; Gruber, Arthur; Koonin, Eugene V; Kupczok, Anne; Lemey, Philippe; McHardy, Alice C; McMahon, Dino P; Pickett, Brett E; Robertson, David L; Scheuermann, Richard H; Zhernakova, Alexandra; Zwart, Mark P; Schönhuth, Alexander; Dutilh, Bas E; Marz, Manja

2018-05-14

The Second Annual Meeting of the European Virus Bioinformatics Center (EVBC), held in Utrecht, Netherlands, focused on computational approaches in virology, with topics including (but not limited to) virus discovery, diagnostics, (meta-)genomics, modeling, epidemiology, molecular structure, evolution, and viral ecology. The goals of the Second Annual Meeting were threefold: (i) to bring together virologists and bioinformaticians from across the academic, industrial, professional, and training sectors to share best practice; (ii) to provide a meaningful and interactive scientific environment to promote discussion and collaboration between students, postdoctoral fellows, and both new and established investigators; (iii) to inspire and suggest new research directions and questions. Approximately 120 researchers from around the world attended the Second Annual Meeting of the EVBC this year, including 15 renowned international speakers. This report presents an overview of new developments and novel research findings that emerged during the meeting.

Characteristic of pandemic virus

Indian Academy of Sciences (India)

First page Back Continue Last page Graphics. Characteristic of pandemic virus. The virus was highly transmissible. Risk of hospitalization was 2X and risk of death was about 11X more in comparison to seasonal influenza. Virus continues to be susceptible to Osaltamivir, the only drug available. Vaccines are available but ...

Avian influenza viruses in humans.

Science.gov (United States)

Malik Peiris, J S

2009-04-01

Past pandemics arose from low pathogenic avian influenza (LPAI) viruses. In more recent times, highly pathogenic avian influenza (HPAI) H5N1, LPAI H9N2 and both HPAI and LPAI H7 viruses have repeatedly caused zoonotic disease in humans. Such infections did not lead to sustained human-to-human transmission. Experimental infection of human volunteers and seroepidemiological studies suggest that avian influenza viruses of other subtypes may also infect humans. Viruses of the H7 subtype appear to have a predilection to cause conjunctivitis and influenza-like illness (ILI), although HPAI H7N7 virus has also caused fatal respiratory disease. Low pathogenic H9N2 viruses have caused mild ILI and its occurrence may be under-recognised for this reason. In contrast, contemporary HPAI H5N1 viruses are exceptional in their virulence for humans and differ from human seasonal influenza viruses in their pathogenesis. Patients have a primary viral pneumonia progressing to acute respiratory distress syndrome (ARDS) and multiple organ dysfunction syndrome. Over 380 human cases have been confirmed to date, with an overall case fatality of 63%. The zoonotic transmission of avian influenza is a rare occurrence, butthe greater public health concern is the adaptation of such viruses to efficient human transmission, which could lead to a pandemic. A better understanding of the ecology of avian influenza viruses and the biological determinants of transmissibility and pathogenicity in humans is important for pandemic preparedness.

Zika virus infection: a public health emergency!

OpenAIRE

Qureshi, Muhammad Salman Haider; Qureshi, Bakhtawar Wajeeha; Khan, Ramsha

2017-01-01

Zika virus belongs to the family of Flaviviridae. The Flaviviridae family also includes other human pathogens like West Nile virus (WNV), Yellow fever virus (YFV), mosquito transmitted Dengue virus (DENV), Tick borne encephalitic virus (TBEV) and Japanese encephalitis virus (JEV). Zika virus is a mosquito-borne disease and is transmitted by Aedes aegypti mosquito.

Analyzing machupo virus-receptor binding by molecular dynamics simulations

Directory of Open Access Journals (Sweden)

Austin G. Meyer

2014-02-01

Full Text Available In many biological applications, we would like to be able to computationally predict mutational effects on affinity in protein–protein interactions. However, many commonly used methods to predict these effects perform poorly in important test cases. In particular, the effects of multiple mutations, non alanine substitutions, and flexible loops are difficult to predict with available tools and protocols. We present here an existing method applied in a novel way to a new test case; we interrogate affinity differences resulting from mutations in a host–virus protein–protein interface. We use steered molecular dynamics (SMD to computationally pull the machupo virus (MACV spike glycoprotein (GP1 away from the human transferrin receptor (hTfR1. We then approximate affinity using the maximum applied force of separation and the area under the force-versus-distance curve. We find, even without the rigor and planning required for free energy calculations, that these quantities can provide novel biophysical insight into the GP1/hTfR1 interaction. First, with no prior knowledge of the system we can differentiate among wild type and mutant complexes. Moreover, we show that this simple SMD scheme correlates well with relative free energy differences computed via free energy perturbation. Second, although the static co-crystal structure shows two large hydrogen-bonding networks in the GP1/hTfR1 interface, our simulations indicate that one of them may not be important for tight binding. Third, one viral site known to be critical for infection may mark an important evolutionary suppressor site for infection-resistant hTfR1 mutants. Finally, our approach provides a framework to compare the effects of multiple mutations, individually and jointly, on protein–protein interactions.

Analyzing machupo virus-receptor binding by molecular dynamics simulations

Science.gov (United States)

Sawyer, Sara L.; Ellington, Andrew D.; Wilke, Claus O.

2014-01-01

In many biological applications, we would like to be able to computationally predict mutational effects on affinity in protein–protein interactions. However, many commonly used methods to predict these effects perform poorly in important test cases. In particular, the effects of multiple mutations, non alanine substitutions, and flexible loops are difficult to predict with available tools and protocols. We present here an existing method applied in a novel way to a new test case; we interrogate affinity differences resulting from mutations in a host–virus protein–protein interface. We use steered molecular dynamics (SMD) to computationally pull the machupo virus (MACV) spike glycoprotein (GP1) away from the human transferrin receptor (hTfR1). We then approximate affinity using the maximum applied force of separation and the area under the force-versus-distance curve. We find, even without the rigor and planning required for free energy calculations, that these quantities can provide novel biophysical insight into the GP1/hTfR1 interaction. First, with no prior knowledge of the system we can differentiate among wild type and mutant complexes. Moreover, we show that this simple SMD scheme correlates well with relative free energy differences computed via free energy perturbation. Second, although the static co-crystal structure shows two large hydrogen-bonding networks in the GP1/hTfR1 interface, our simulations indicate that one of them may not be important for tight binding. Third, one viral site known to be critical for infection may mark an important evolutionary suppressor site for infection-resistant hTfR1 mutants. Finally, our approach provides a framework to compare the effects of multiple mutations, individually and jointly, on protein–protein interactions. PMID:24624315

Human Parainfluenza Viruses

Science.gov (United States)

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

Respiratory Syncytial Virus

Science.gov (United States)

... with facebook share with twitter share with linkedin Respiratory Syncytial Virus (RSV) Credit: CDC This is the ... the United States. Why Is the Study of Respiratory Syncytial Virus (RSV) a Priority for NIAID? In ...

Partial characterization of the lettuce infectious yellows virus genomic RNAs, identification of the coat protein gene and comparison of its amino acid sequence with those of other filamentous RNA plant viruses.

Science.gov (United States)

Klaassen, V A; Boeshore, M; Dolja, V V; Falk, B W

1994-07-01

Purified virions of lettuce infectious yellows virus (LIYV), a tentative member of the closterovirus group, contained two RNAs of approximately 8500 and 7300 nucleotides (RNAs 1 and 2 respectively) and a single coat protein species with M(r) of approximately 28,000. LIYV-infected plants contained multiple dsRNAs. The two largest were the correct size for the replicative forms of LIYV virion RNAs 1 and 2. To assess the relationships between LIYV RNAs 1 and 2, cDNAs corresponding to the virion RNAs were cloned. Northern blot hybridization analysis showed no detectable sequence homology between these RNAs. A partial amino acid sequence obtained from purified LIYV coat protein was found to align in the most upstream of four complete open reading frames (ORFs) identified in a LIYV RNA 2 cDNA clone. The identity of this ORF was confirmed as the LIYV coat protein gene by immunological analysis of the gene product expressed in vitro and in Escherichia coli. Computer analysis of the LIYV coat protein amino acid sequence indicated that it belongs to a large family of proteins forming filamentous capsids of RNA plant viruses. The LIYV coat protein appears to be most closely related to the coat proteins of two closteroviruses, beet yellows virus and citrus tristeza virus.

Antiviral Activity of Sukomycin Against Potato Virus Y And Tomato Mosaic Virus

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Nikolay Petrov

2016-12-01

Full Text Available Potato virus Y (PVY and Tomato mosaic virus (ToMV are one of the most important plant viruses that strongly influence the quality and quantity of vegetable production and cause substantial losses to farmers. The most convetional and common method of pest and disease control is trough the use of pesticides. Unfortunately, most of them are synthetic compounds without antiviral activities and possess inherent toxicities that endanger the health of the farm operators, consumers and the environment. In order to carry out a control of viral infections in plants and to reduce the loss of production it is necessary the search for alternative and environmentally friendly methods for control. Sukomycin is a complex of substances with antimicrobial and antiviral activities produced from Streptomyces hygroscopicus isolated from soil. This natural complex reduces significantly symptoms and DAS-ELISA values of Potato virus Y and Tomato mosaic virus in tobacco plants.

Prevention of Hepatitis B Virus and Hepatitis C Virus Transmission ...

African Journals Online (AJOL)

Introduction: Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in hemodialysis (HD) patients are associated with adverse outcomes, especially after kidney transplantation. Review: In the HD setting, cross-contamination to patients via environmental surfaces, supplies, equipment, multiple-dose medication vials ...

A literature review on cardiovascular risk in human immunodeficiency virus-infected patients: implications for clinical management

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Mansueto Gomes Neto

Full Text Available INTRODUCTION: In recent years, there has been growing concern about an increasing rate of cardiovascular diseases in human immunodeficiency virus-infected patients, which could be associated with side effects of highly active antiretroviral therapy. It is likely that the metabolic disorders related to anti-human immunodeficiency virus treatment will eventually translate into a increased cardiovascular risk in patients submitted to such regimens. OBJECTIVE: To evaluate if human immunodeficiency virus-infected patients receiving highly active antiretroviral therapy are at higher risk of cardiovascular diseases than human immunodeficiency virus infected patients not receiving highly active antiretroviral therapy, or the general population. RESEARCH DESIGN AND METHODS: We conducted a computer-based search in representative databases, and also performed manual tracking of citations in selected articles. RESULT: The available evidence suggests an excess risk of cardiovascular events in human immunodeficiency virus-infected persons compared to non-human immunodeficiency virus infected individuals. The use of highly active antiretroviral therapy is associated with increased levels of total cholesterol, triglycerides, low-density lipoprotein and morphological signs of cardiovascular diseases. Some evidence suggested that human immunodeficiency virus-infected individuals on highly active antiretroviral therapy regimens are at increased risk of dyslipidemia, ischemic heart disease, and myocardial infarction, particularly if the highly active antiretroviral therapy regimen contains a protease inhibitor. CONCLUSION: Physicians must weigh the cardiovascular risk against potential benefits when prescribing highly active antiretroviral therapy. Careful cardiac screening is warranted for patients who are being evaluated for, or who are receiving highly active antiretroviral therapy regimens, particularly for those with known underlying cardiovascular risk

A fusion-inhibiting peptide against Rift Valley fever virus inhibits multiple, diverse viruses.

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Jeffrey W Koehler

Full Text Available For enveloped viruses, fusion of the viral envelope with a cellular membrane is critical for a productive infection to occur. This fusion process is mediated by at least three classes of fusion proteins (Class I, II, and III based on the protein sequence and structure. For Rift Valley fever virus (RVFV, the glycoprotein Gc (Class II fusion protein mediates this fusion event following entry into the endocytic pathway, allowing the viral genome access to the cell cytoplasm. Here, we show that peptides analogous to the RVFV Gc stem region inhibited RVFV infectivity in cell culture by inhibiting the fusion process. Further, we show that infectivity can be inhibited for diverse, unrelated RNA viruses that have Class I (Ebola virus, Class II (Andes virus, or Class III (vesicular stomatitis virus fusion proteins using this single peptide. Our findings are consistent with an inhibition mechanism similar to that proposed for stem peptide fusion inhibitors of dengue virus in which the RVFV inhibitory peptide first binds to both the virion and cell membranes, allowing it to traffic with the virus into the endocytic pathway. Upon acidification and rearrangement of Gc, the peptide is then able to specifically bind to Gc and prevent fusion of the viral and endocytic membranes, thus inhibiting viral infection. These results could provide novel insights into conserved features among the three classes of viral fusion proteins and offer direction for the future development of broadly active fusion inhibitors.

Inactivated Recombinant Rabies Viruses Displaying Canine Distemper Virus Glycoproteins Induce Protective Immunity against Both Pathogens.

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da Fontoura Budaszewski, Renata; Hudacek, Andrew; Sawatsky, Bevan; Krämer, Beate; Yin, Xiangping; Schnell, Matthias J; von Messling, Veronika

2017-04-15

The development of multivalent vaccines is an attractive methodology for the simultaneous prevention of several infectious diseases in vulnerable populations. Both canine distemper virus (CDV) and rabies virus (RABV) cause lethal disease in wild and domestic carnivores. While RABV vaccines are inactivated, the live-attenuated CDV vaccines retain residual virulence for highly susceptible wildlife species. In this study, we developed recombinant bivalent vaccine candidates based on recombinant vaccine strain rabies virus particles, which concurrently display the protective CDV and RABV glycoprotein antigens. The recombinant viruses replicated to near-wild-type titers, and the heterologous glycoproteins were efficiently expressed and incorporated in the viral particles. Immunization of ferrets with beta-propiolactone-inactivated recombinant virus particles elicited protective RABV antibody titers, and animals immunized with a combination of CDV attachment protein- and fusion protein-expressing recombinant viruses were protected from lethal CDV challenge. However, animals that were immunized with only a RABV expressing the attachment protein of CDV vaccine strain Onderstepoort succumbed to infection with a more recent wild-type strain, indicating that immune responses to the more conserved fusion protein contribute to protection against heterologous CDV strains. IMPORTANCE Rabies virus and canine distemper virus (CDV) cause high mortality rates and death in many carnivores. While rabies vaccines are inactivated and thus have an excellent safety profile and high stability, live-attenuated CDV vaccines can retain residual virulence in highly susceptible species. Here we generated recombinant inactivated rabies viruses that carry one of the CDV glycoproteins on their surface. Ferrets immunized twice with a mix of recombinant rabies viruses carrying the CDV fusion and attachment glycoproteins were protected from lethal CDV challenge, whereas all animals that received

Archaeal Viruses from High-Temperature Environments.

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Munson-McGee, Jacob H; Snyder, Jamie C; Young, Mark J

2018-02-27

Archaeal viruses are some of the most enigmatic viruses known, due to the small number that have been characterized to date. The number of known archaeal viruses lags behind known bacteriophages by over an order of magnitude. Despite this, the high levels of genetic and morphological diversity that archaeal viruses display has attracted researchers for over 45 years. Extreme natural environments, such as acidic hot springs, are almost exclusively populated by Archaea and their viruses, making these attractive environments for the discovery and characterization of new viruses. The archaeal viruses from these environments have provided insights into archaeal biology, gene function, and viral evolution. This review focuses on advances from over four decades of archaeal virology, with a particular focus on archaeal viruses from high temperature environments, the existing challenges in understanding archaeal virus gene function, and approaches being taken to overcome these limitations.

Archaeal Viruses from High-Temperature Environments

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Jacob H. Munson-McGee

2018-02-01

Full Text Available Archaeal viruses are some of the most enigmatic viruses known, due to the small number that have been characterized to date. The number of known archaeal viruses lags behind known bacteriophages by over an order of magnitude. Despite this, the high levels of genetic and morphological diversity that archaeal viruses display has attracted researchers for over 45 years. Extreme natural environments, such as acidic hot springs, are almost exclusively populated by Archaea and their viruses, making these attractive environments for the discovery and characterization of new viruses. The archaeal viruses from these environments have provided insights into archaeal biology, gene function, and viral evolution. This review focuses on advances from over four decades of archaeal virology, with a particular focus on archaeal viruses from high temperature environments, the existing challenges in understanding archaeal virus gene function, and approaches being taken to overcome these limitations.

A Foxtail mosaic virus Vector for Virus-Induced Gene Silencing in Maize1[OPEN

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Mei, Yu; Kernodle, Bliss M.; Hill, John H.

2016-01-01

Plant viruses have been widely used as vectors for foreign gene expression and virus-induced gene silencing (VIGS). A limited number of viruses have been developed into viral vectors for the purposes of gene expression or VIGS in monocotyledonous plants, and among these, the tripartite viruses Brome mosaic virus and Cucumber mosaic virus have been shown to induce VIGS in maize (Zea mays). We describe here a new DNA-based VIGS system derived from Foxtail mosaic virus (FoMV), a monopartite virus that is able to establish systemic infection and silencing of endogenous maize genes homologous to gene fragments inserted into the FoMV genome. To demonstrate VIGS applications of this FoMV vector system, four genes, phytoene desaturase (functions in carotenoid biosynthesis), lesion mimic22 (encodes a key enzyme of the porphyrin pathway), iojap (functions in plastid development), and brown midrib3 (caffeic acid O-methyltransferase), were silenced and characterized in the sweet corn line Golden × Bantam. Furthermore, we demonstrate that the FoMV infectious clone establishes systemic infection in maize inbred lines, sorghum (Sorghum bicolor), and green foxtail (Setaria viridis), indicating the potential wide applications of this viral vector system for functional genomics studies in maize and other monocots. PMID:27208311

A fatal case of middle east respiratory syndrome corona virus infection in South Korea: Cheat radiography and CT findings

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Eun; Kim, Hyo Lim; Choi, Su Mi [Dept. of Internal Medicine, Yeouido St. Mary' s Hospital, The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of)

2016-06-15

The outbreak of Middle East Respiratory Syndrome Corona Virus (MERS-CoV) infection in South Korea originated from Saudi Arabia. This virus shows high infectivity, and causes outbreaks of severe febrile respiratory infections in health care-associated settings. Herein, we reported a fatal case of MERS-CoV infection with a focus on the pulmonary radiologic findings. The initial chest computed tomography and radiographs of our patient showed ground-glass opacity in patchy distribution, followed by rapid progression of consolidation and pleural effusion in serial studies.

A fatal case of middle east respiratory syndrome corona virus infection in South Korea: Cheat radiography and CT findings

International Nuclear Information System (INIS)

Lee, Seung Eun; Kim, Hyo Lim; Choi, Su Mi

2016-01-01

The outbreak of Middle East Respiratory Syndrome Corona Virus (MERS-CoV) infection in South Korea originated from Saudi Arabia. This virus shows high infectivity, and causes outbreaks of severe febrile respiratory infections in health care-associated settings. Herein, we reported a fatal case of MERS-CoV infection with a focus on the pulmonary radiologic findings. The initial chest computed tomography and radiographs of our patient showed ground-glass opacity in patchy distribution, followed by rapid progression of consolidation and pleural effusion in serial studies

A human torque teno virus encodes a microRNA that inhibits interferon signaling.

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Rodney P Kincaid

Full Text Available Torque teno viruses (TTVs are a group of viruses with small, circular DNA genomes. Members of this family are thought to ubiquitously infect humans, although causal disease associations are currently lacking. At present, there is no understanding of how infection with this diverse group of viruses is so prevalent. Using a combined computational and synthetic approach, we predict and identify miRNA-coding regions in diverse human TTVs and provide evidence for TTV miRNA production in vivo. The TTV miRNAs are transcribed by RNA polymerase II, processed by Drosha and Dicer, and are active in RISC. A TTV mutant defective for miRNA production replicates as well as wild type virus genome; demonstrating that the TTV miRNA is dispensable for genome replication in a cell culture model. We demonstrate that a recombinant TTV genome is capable of expressing an exogenous miRNA, indicating the potential utility of TTV as a small RNA vector. Gene expression profiling of host cells identifies N-myc (and STAT interactor (NMI as a target of a TTV miRNA. NMI transcripts are directly regulated through a binding site in the 3'UTR. SiRNA knockdown of NMI contributes to a decreased response to interferon signaling. Consistent with this, we show that a TTV miRNA mediates a decreased response to IFN and increased cellular proliferation in the presence of IFN. Thus, we add Annelloviridae to the growing list of virus families that encode miRNAs, and suggest that miRNA-mediated immune evasion can contribute to the pervasiveness associated with some of these viruses.

Avian influenza virus transmission to mammals.

Science.gov (United States)

Herfst, S; Imai, M; Kawaoka, Y; Fouchier, R A M

2014-01-01

Influenza A viruses cause yearly epidemics and occasional pandemics. In addition, zoonotic influenza A viruses sporadically infect humans and may cause severe respiratory disease and fatalities. Fortunately, most of these viruses do not have the ability to be efficiently spread among humans via aerosols or respiratory droplets (airborne transmission) and to subsequently cause a pandemic. However, adaptation of these zoonotic viruses to humans by mutation or reassortment with human influenza A viruses may result in airborne transmissible viruses with pandemic potential. Although our knowledge of factors that affect mammalian adaptation and transmissibility of influenza viruses is still limited, we are beginning to understand some of the biological traits that drive airborne transmission of influenza viruses among mammals. Increased understanding of the determinants and mechanisms of airborne transmission may aid in assessing the risks posed by avian influenza viruses to human health, and preparedness for such risks. This chapter summarizes recent discoveries on the genetic and phenotypic traits required for avian influenza viruses to become airborne transmissible between mammals.

Zika virus disease

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... May 2015, the virus was discovered for the first time in Brazil. It has now spread to many territories, states, and countries in: Caribbean Islands Central America Mexico South America Pacific Islands Africa The virus ...

A recombinant canine distemper virus expressing a modified rabies virus glycoprotein induces immune responses in mice.

Science.gov (United States)

Li, Zhili; Wang, Jigui; Yuan, Daoli; Wang, Shuang; Sun, Jiazeng; Yi, Bao; Hou, Qiang; Mao, Yaping; Liu, Weiquan

2015-06-01

Canine distemper virus (CDV) and rabies virus (RV) are two important pathogens of the dog. CDV, a member of the morbillivirus genus, has shown promise as an expression vector. The glycoprotein from RV is a main contributor to protective immunity and capable of eliciting the production of virus-neutralizing antibodies. In this study, we recovered an attenuated strain of canine distemper virus and constructed a recombinant virus, rCDV-RV-G, expressing a modified (R333Q) rabies virus glycoprotein (RV-G) of RV Flury strain LEP. RV-G expression by the recombinant viruses was confirmed. Furthermore, G was proved to be incorporated into the surface of CDV particles. While replication of the recombinant virus was slightly reduced compared with the parental CDV, it stably expressed the RV-G over ten serial passages. Inoculation of mice induced specific neutralizing antibodies against both RV-G and CDV. Therefore, the rCDV-RV-G has the potential as a vaccine that may be used to control rabies virus infection in dogs and other animals.

Identification and characterization of a virus-specific continuous B-cell epitope on the PrM/M protein of Japanese Encephalitis Virus: potential application in the detection of antibodies to distinguish Japanese Encephalitis Virus infection from West Nile Virus and Dengue Virus infections

OpenAIRE

Hua, Rong-Hong; Chen, Na-Sha; Qin, Cheng-Feng; Deng, Yong-Qiang; Ge, Jin-Ying; Wang, Xi-Jun; Qiao, Zu-Jian; Chen, Wei-Ye; Wen, Zhi-Yuan; Liu, Wen-Xin; Hu, Sen; Bu, Zhi-Gao

2010-01-01

Abstract Background Differential diagnose of Japanese encephalitis virus (JEV) infection from other flavivirus especially West Nile virus (WNV) and Dengue virus (DV) infection was greatly hindered for the serological cross-reactive. Virus specific epitopes could benefit for developing JEV specific antibodies detection methods. To identify the JEV specific epitopes, we fully mapped and characterized the continuous B-cell epitope of the PrM/M protein of JEV. Results To map the epitopes on the P...

Expression of varicella-zoster virus and herpes simplex virus in normal human trigeminal ganglia

International Nuclear Information System (INIS)

Vafai, A.; Wellish, M.; Devlin, M.; Gilden, D.H.; Murray, R.S.

1988-01-01

Lysates of radiolabeled explants from four human trigeminal ganglia were immunoprecipitated with antibodies to varicella-zoster virus (VZV) and to herpes simplex virus. Both herpes simplex virus- and VZV-specific proteins were detected in lysates of all four ganglia. Absence of reactivity in ganglion explants with monoclonal antibodies suggested that herpes simplex virus and VZV were not reactivated during the culture period. In situ hybridization studies demonstrated the presence of RNA transcripts from the VZV immediate early gene 63. This approach to the detection of herpes simplex virus and VZV expression in human ganglia should facilitate analysis of viral RNA and proteins in human sensory ganglia

Thermoactivation of viruses by microwaves

Energy Technology Data Exchange (ETDEWEB)

Mahnel, H.; von Brodorotti, H.S.

1981-01-01

Eight different viruses, suspended in drinking water, were examined for their ability to be inactivated by microwaves from a microwave oven. Up to a virus content of 10/sup 5/ TCID/sub 50//ml inactivation was successful within a few minutes of microwave treatment and occurred in parallel to the heat stability of the viruses. Evidence for direct effects of microwaves on viruses could not be detected. 7 of the viruses studied were inactivated rapidly when temperatures of 50 to 65/sup 0/C under microwave treatment were reached in the flowing water, while a bovine parvovirus was only inactivated by temperatures above 90/sup 0/C. The advantages of a thermal virus-decontamination of fluids and material by microwaves are discussed.

Autophagic machinery activated by dengue virus enhances virus replication

International Nuclear Information System (INIS)

Lee, Y.-R.; Lei, H.-Y.; Liu, M.-T.; Wang, J.-R.; Chen, S.-H.; Jiang-Shieh, Y.-F.; Lin, Y.-S.; Yeh, T.-M.; Liu, C.-C.; Liu, H.-S.

2008-01-01

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

Animal Models of Zika Virus

Science.gov (United States)

Bradley, Michael P; Nagamine, Claude M

2017-01-01

Zika virus has garnered great attention over the last several years, as outbreaks of the disease have emerged throughout the Western Hemisphere. Until quite recently Zika virus was considered a fairly benign virus, with limited clinical severity in both people and animals. The size and scope of the outbreak in the Western Hemisphere has allowed for the identification of severe clinical disease that is associated with Zika virus infection, most notably microcephaly among newborns, and an association with Guillian–Barré syndrome in adults. This recent association with severe clinical disease, of which further analysis strongly suggested causation by Zika virus, has resulted in a massive increase in the amount of both basic and applied research of this virus. Both small and large animal models are being used to uncover the pathogenesis of this emerging disease and to develop vaccine and therapeutic strategies. Here we review the animal-model–based Zika virus research that has been performed to date. PMID:28662753

78 FR 29755 - Human Immunodeficiency Virus Patient-Focused Drug Development and Human Immunodeficiency Virus...

Science.gov (United States)

2013-05-21

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2013-N-0473] Human Immunodeficiency Virus Patient-Focused Drug Development and Human Immunodeficiency Virus Cure... an opportunity for public comment on human immunodeficiency virus (HIV) Patient-Focused Drug...

Exploring nucleo-cytoplasmic large DNA viruses in Tara Oceans microbial metagenomes.

Science.gov (United States)

Hingamp, Pascal; Grimsley, Nigel; Acinas, Silvia G; Clerissi, Camille; Subirana, Lucie; Poulain, Julie; Ferrera, Isabel; Sarmento, Hugo; Villar, Emilie; Lima-Mendez, Gipsi; Faust, Karoline; Sunagawa, Shinichi; Claverie, Jean-Michel; Moreau, Hervé; Desdevises, Yves; Bork, Peer; Raes, Jeroen; de Vargas, Colomban; Karsenti, Eric; Kandels-Lewis, Stefanie; Jaillon, Olivier; Not, Fabrice; Pesant, Stéphane; Wincker, Patrick; Ogata, Hiroyuki

2013-09-01

Nucleo-cytoplasmic large DNA viruses (NCLDVs) constitute a group of eukaryotic viruses that can have crucial ecological roles in the sea by accelerating the turnover of their unicellular hosts or by causing diseases in animals. To better characterize the diversity, abundance and biogeography of marine NCLDVs, we analyzed 17 metagenomes derived from microbial samples (0.2-1.6 μm size range) collected during the Tara Oceans Expedition. The sample set includes ecosystems under-represented in previous studies, such as the Arabian Sea oxygen minimum zone (OMZ) and Indian Ocean lagoons. By combining computationally derived relative abundance and direct prokaryote cell counts, the abundance of NCLDVs was found to be in the order of 10(4)-10(5) genomes ml(-1) for the samples from the photic zone and 10(2)-10(3) genomes ml(-1) for the OMZ. The Megaviridae and Phycodnaviridae dominated the NCLDV populations in the metagenomes, although most of the reads classified in these families showed large divergence from known viral genomes. Our taxon co-occurrence analysis revealed a potential association between viruses of the Megaviridae family and eukaryotes related to oomycetes. In support of this predicted association, we identified six cases of lateral gene transfer between Megaviridae and oomycetes. Our results suggest that marine NCLDVs probably outnumber eukaryotic organisms in the photic layer (per given water mass) and that metagenomic sequence analyses promise to shed new light on the biodiversity of marine viruses and their interactions with potential hosts.

Alfalfa virus S, a new species in the family Alphaflexiviridae.

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Lev G Nemchinov

Full Text Available A new species of the family Alphaflexiviridae provisionally named alfalfa virus S (AVS was discovered in alfalfa samples originating from Sudan. A complete nucleotide sequence of the viral genome consisting of 8,349 nucleotides excluding the 3' poly(A tail was determined by high throughput sequencing (HTS on an Illumina platform. NCBI BLAST searches revealed that the virus shares the greatest degree of sequence identity with members of the family Alphaflexiviridae, genus Allexivirus. The AVS genome contains six computationally-predicted open reading frames (ORF encoding viral replication protein, triple gene block protein 1 (TGB1, TGB2, TGB3-like protein, unknown 38.4 kDa protein resembling serine-rich 40 kDa protein characteristic for allexiviruses, and coat protein (CP. AVS lacks a clear 3' proximal ORF that encodes a nucleic acid-binding protein typical for allexiviruses. The identity of the virus was confirmed by RT-PCR with primers derived from the HTS-generated sequence, dot blot hybridization with DIG-labeled virus-specific RNA probes, and Western blot analysis with antibodies produced against a peptide derived from the CP sequence. Transmission electron microscopic observations of the infected tissues showed the presence of filamentous particles similar to allexiviruses in their length and appearance. To the best of our knowledge, this is the first report on the identification of a putative allexivirus in alfalfa (Medicago sativa. The genome sequence of AVS has been deposited in NCBI GenBank on 03/02/2016 as accession № KY696659.

Natural history and treatment of hepatitis B virus and hepatitis C virus coinfection

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Keeffe Emmet B

2005-09-01

Full Text Available Abstract Hepatitis B virus (HBV and hepatitis C virus (HCV coinfection is not uncommon as a result of similar routes of infection. Patients who are coinfected represent a unique group with diverse serologic profiles. Combined chronic hepatitis B and C leads to more severe liver disease and an increased risk of hepatocellular carcinoma. Furthermore, coinfected patients represent a treatment challenge. No standard recommendations exist for treatment of viral hepatitis due to dual HBV/HCV infection, and therefore treatment must be individualized based on patient variables such as serologic and virologic profiles, patient's prior exposure to antiviral treatment, and the presence of other parenterally transmitted viruses such as hepatitis D virus and human immunodeficiency virus. The natural history and treatment of patients with HBV and HCV coinfection is reviewed.

The Classroom, Board Room, Chat Room, and Court Room: School Computers at the Crossroads.

Science.gov (United States)

Stewart, Michael

2000-01-01

In schools' efforts to maximize technology's benefits, ethical considerations have often taken a back seat. Computer misuse is growing exponentially and assuming many forms: unauthorized data access, hacking, piracy, information theft, fraud, virus creation, harassment, defamation, and discrimination. Integrated-learning activities will help…

Codon usage bias and the evolution of influenza A viruses. Codon Usage Biases of Influenza Virus

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Wong Emily HM

2010-08-01

Full Text Available Abstract Background The influenza A virus is an important infectious cause of morbidity and mortality in humans and was responsible for 3 pandemics in the 20th century. As the replication of the influenza virus is based on its host's machinery, codon usage of its viral genes might be subject to host selection pressures, especially after interspecies transmission. A better understanding of viral evolution and host adaptive responses might help control this disease. Results Relative Synonymous Codon Usage (RSCU values of the genes from segment 1 to segment 6 of avian and human influenza viruses, including pandemic H1N1, were studied via Correspondence Analysis (CA. The codon usage patterns of seasonal human influenza viruses were distinct among their subtypes and different from those of avian viruses. Newly isolated viruses could be added to the CA results, creating a tool to investigate the host origin and evolution of viral genes. It was found that the 1918 pandemic H1N1 virus contained genes with mammalian-like viral codon usage patterns, indicating that the introduction of this virus to humans was not through in toto transfer of an avian influenza virus. Many human viral genes had directional changes in codon usage over time of viral isolation, indicating the effect of host selection pressures. These changes reduced the overall GC content and the usage of G at the third codon position in the viral genome. Limited evidence of translational selection pressure was found in a few viral genes. Conclusions Codon usage patterns from CA allowed identification of host origin and evolutionary trends in influenza viruses, providing an alternative method and a tool to understand the evolution of influenza viruses. Human influenza viruses are subject to selection pressure on codon usage which might assist in understanding the characteristics of newly emerging viruses.

78 FR 46969 - Human Immunodeficiency Virus Patient-Focused Drug Development and Human Immunodeficiency Virus...

Science.gov (United States)

2013-08-02

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2013-N-0473] Human Immunodeficiency Virus Patient-Focused Drug Development and Human Immunodeficiency Virus Cure... for the notice of public meeting entitled ``Human Immunodeficiency Virus (HIV) Patient-Focused Drug...

Chimeric human parainfluenza virus bearing the Ebola virus glycoprotein as the sole surface protein is immunogenic and highly protective against Ebola virus challenge

International Nuclear Information System (INIS)

Bukreyev, Alexander; Marzi, Andrea; Feldmann, Friederike; Zhang Liqun; Yang Lijuan; Ward, Jerrold M.; Dorward, David W.; Pickles, Raymond J.; Murphy, Brian R.; Feldmann, Heinz; Collins, Peter L.

2009-01-01

We generated a new live-attenuated vaccine against Ebola virus (EBOV) based on a chimeric virus HPIV3/ΔF-HN/EboGP that contains the EBOV glycoprotein (GP) as the sole transmembrane envelope protein combined with the internal proteins of human parainfluenza virus type 3 (HPIV3). Electron microscopy analysis of the virus particles showed that they have an envelope and surface spikes resembling those of EBOV and a particle size and shape resembling those of HPIV3. When HPIV3/ΔF-HN/EboGP was inoculated via apical surface of an in vitro model of human ciliated airway epithelium, the virus was released from the apical surface; when applied to basolateral surface, the virus infected basolateral cells but did not spread through the tissue. Following intranasal (IN) inoculation of guinea pigs, scattered infected cells were detected in the lungs by immunohistochemistry, but infectious HPIV3/ΔF-HN/EboGP could not be recovered from the lungs, blood, or other tissues. Despite the attenuation, the virus was highly immunogenic, and a single IN dose completely protected the animals against a highly lethal intraperitoneal challenge of guinea pig-adapted EBOV

Predicting Zoonotic Risk of Influenza A Viruses from Host Tropism Protein Signature Using Random Forest.

Science.gov (United States)

Eng, Christine L P; Tong, Joo Chuan; Tan, Tin Wee

2017-05-25

Influenza A viruses remain a significant health problem, especially when a novel subtype emerges from the avian population to cause severe outbreaks in humans. Zoonotic viruses arise from the animal population as a result of mutations and reassortments, giving rise to novel strains with the capability to evade the host species barrier and cause human infections. Despite progress in understanding interspecies transmission of influenza viruses, we are no closer to predicting zoonotic strains that can lead to an outbreak. We have previously discovered distinct host tropism protein signatures of avian, human and zoonotic influenza strains obtained from host tropism predictions on individual protein sequences. Here, we apply machine learning approaches on the signatures to build a computational model capable of predicting zoonotic strains. The zoonotic strain prediction model can classify avian, human or zoonotic strains with high accuracy, as well as providing an estimated zoonotic risk. This would therefore allow us to quickly determine if an influenza virus strain has the potential to be zoonotic using only protein sequences. The swift identification of potential zoonotic strains in the animal population using the zoonotic strain prediction model could provide us with an early indication of an imminent influenza outbreak.

VIRUS instrument enclosures

Science.gov (United States)

Prochaska, T.; Allen, R.; Mondrik, N.; Rheault, J. P.; Sauseda, M.; Boster, E.; James, M.; Rodriguez-Patino, M.; Torres, G.; Ham, J.; Cook, E.; Baker, D.; DePoy, Darren L.; Marshall, Jennifer L.; Hill, G. J.; Perry, D.; Savage, R. D.; Good, J. M.; Vattiat, Brian L.

2014-08-01

The Visible Integral-Field Replicable Unit Spectrograph (VIRUS) instrument will be installed at the Hobby-Eberly Telescope† in the near future. The instrument will be housed in two enclosures that are mounted adjacent to the telescope, via the VIRUS Support Structure (VSS). We have designed the enclosures to support and protect the instrument, to enable servicing of the instrument, and to cool the instrument appropriately while not adversely affecting the dome environment. The system uses simple HVAC air handling techniques in conjunction with thermoelectric and standard glycol heat exchangers to provide efficient heat removal. The enclosures also provide power and data transfer to and from each VIRUS unit, liquid nitrogen cooling to the detectors, and environmental monitoring of the instrument and dome environments. In this paper, we describe the design and fabrication of the VIRUS enclosures and their subsystems.

Hepatitis A virus antibody

International Nuclear Information System (INIS)

Novak, J.; Kselikova, M.; Urbankova, J.

1980-01-01

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

Avian influenza A virus and Newcastle disease virus mono- and co-infections in birds

Directory of Open Access Journals (Sweden)

Iv. Zarkov

2017-06-01

Full Text Available The main features of avian influenza viruses (AIV and Newcastle disease virus (APMV-1, the possibilities for isolation and identification in laboratory conditions, methods of diagnostics, main hosts, clinical signs and virus shedding are reviewed in chronological order. The other part of the review explains the mechanisms and interactions in cases of co-infection of AIV and APMV-1, either between them or with other pathogens in various indicator systems – cell cultures, chick embryos or birds. The emphasis is placed on quantitative data on the virus present mainly in the first ten days following experimental infection of birds, the periods of virus carrier ship and shedding, clinical signs, pathological changes, diagnostic challenges

BS-virus-finder

DEFF Research Database (Denmark)

Gao, Shengjie; Hu, Xuesong; Xu, Fengping

2018-01-01

Background: DNA methylation plays a key role in the regulation of gene expression and carcinogenesis. Bisulfite sequencing studies mainly focus on calling SNP, DMR, and ASM. Until now, only a few software tools focus on virus integration using bisulfite sequencing data. Findings: We have developed...... a new and easy-to-use software tool, named BS-virus-finder (BSVF, RRID:SCR_015727), to detect viral integration breakpoints in whole human genomes. The tool is hosted at https://github.com/BGI-SZ/BSVF. Conclusions: BS-virus-finder demonstrates high sensitivity and specificity. It is useful in epigenetic...

Ebola (Ebola Virus Disease): Diagnosis

Science.gov (United States)

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Ebola (Ebola Virus Disease): Transmission

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Ebola (Ebola Virus Disease): Treatment

Science.gov (United States)

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Tomato ringspot virus and Tobacco ringspot virus in Highbush Blueberry in New York State

Science.gov (United States)

A survey of highbush blueberry (Vaccinium corymbosum L.) cultivars Patriot and Bluecrop showing virus-like symptoms and decline in vigor in New York was conducted to assess the occurrence of viruses. Leaf samples from symptomatic and asymptomatic bushes reacted positively to Tobacco ringspot virus ...

Protecting Anti-virus Programs From Viral Attacks

OpenAIRE

Mishra, Umakant

2013-01-01

During a fight between viruses and anti-viruses it is not always predictable that the anti-virus is going to win. There are many malicious viruses which target to attack and paralyze the anti-viruses. It is necessary for an anti-virus to detect and destroy the malware before its own files are detected and destroyed by the malware. The anti-virus may follow thorough testing and auditing procedures to fix all its bugs before releasing the software in the market. Besides the anti-virus may use a...

Remarkable morphological diversity of viruses and virus-like particles in hot terrestrial environments.

Science.gov (United States)

Rachel, R; Bettstetter, M; Hedlund, B P; Häring, M; Kessler, A; Stetter, K O; Prangishvili, D

2002-12-01

Electron microscopic studies of the viruses in two hot springs (85 degrees C, pH 1.5-2.0, and 75-93 degrees C, pH 6.5) in Yellowstone National Park revealed particles with twelve different morphotypes. This diversity encompassed known viruses of hyperthermophilic archaea, filamentous Lipothrixviridae, rod-shaped Rudiviridae, and spindle-shaped Fuselloviridae, and novel morphotypes previously not observed in nature. Two virus types resembled head-and-tail bacteriophages from the families Siphoviridae and Podoviridae, and constituted the first observation of these viruses in a hydrothermal environment. Viral hosts in the acidic spring were members of the hyperthermophilic archaeal genus Acidianus.

General properties of grapevine viruses occurring in Hungary

OpenAIRE

Eszter Cseh; András Takács; László Kocsis; Richard Gáborjányi

2012-01-01

The past fifty years important advances have been made in the field of grapevine virus research, including characterization of pathogens and control measurements. Still the occurrence of Grapevine fanleaf virus (GFLV), Arabis mosaic virus (ArMV), Tomato black ring virus (TBRV), Grapevine chrome mosaic virus (GCMV), Alfalfa mosaic virus (AMV), Grapevine Bulgarian latent virus (GBLV), Grapevine fleck virus (GFkV), Grapevine leafroll- associated viruses (GLRaV1-4), Grapevine virus A (GVA), Grape...

General properties of grapevine viruses occurring in Hungary

Directory of Open Access Journals (Sweden)

Eszter Cseh

2012-03-01

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

Control of sweet potato virus diseases.

Science.gov (United States)

Loebenstein, Gad

2015-01-01

Sweet potato (Ipomoea batatas) is ranked seventh in global food crop production and is the third most important root crop after potato and cassava. Sweet potatoes are vegetative propagated from vines, root slips (sprouts), or tubers. Therefore, virus diseases can be a major constrain, reducing yields markedly, often more than 50%. The main viruses worldwide are Sweet potato feathery mottle virus (SPFMV) and Sweet potato chlorotic stunt virus (SPCSV). Effects on yields by SPFMV or SPCSV alone are minor, or but in complex infection by the two or other viruses yield losses of 50%. The orthodox way of controlling viruses in vegetative propagated crops is by supplying the growers with virus-tested planting material. High-yielding plants are tested for freedom of viruses by PCR, serology, and grafting to sweet potato virus indicator plants. After this, meristem tips are taken from those plants that reacted negative. The meristems were grown into plants which were kept under insect-proof conditions and away from other sweet potato material for distribution to farmers after another cycle of reproduction. © 2015 Elsevier Inc. All rights reserved.

Autophagy in Measles Virus Infection

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Aurore Rozières

2017-11-01

Full Text Available Autophagy is a biological process that helps cells to recycle obsolete cellular components and which greatly contributes to maintaining cellular integrity in response to environmental stress factors. Autophagy is also among the first lines of cellular defense against invading microorganisms, including viruses. The autophagic destruction of invading pathogens, a process referred to as xenophagy, involves cytosolic autophagy receptors, such as p62/SQSTM1 (Sequestosome 1 or NDP52/CALCOCO2 (Nuclear Dot 52 KDa Protein/Calcium Binding And Coiled-Coil Domain 2, which bind to microbial components and target them towards growing autophagosomes for degradation. However, most, if not all, infectious viruses have evolved molecular tricks to escape from xenophagy. Many viruses even use autophagy, part of the autophagy pathway or some autophagy-associated proteins, to improve their infectious potential. In this regard, the measles virus, responsible for epidemic measles, has a unique interface with autophagy as the virus can induce multiple rounds of autophagy in the course of infection. These successive waves of autophagy result from distinct molecular pathways and seem associated with anti- and/or pro-measles virus consequences. In this review, we describe what the autophagy–measles virus interplay has taught us about both the biology of the virus and the mechanistic orchestration of autophagy.

Strategy as a Virus

DEFF Research Database (Denmark)

Obed Madsen, Søren

This article is based on virus theory (Røvik, 2007, 2011), and proposes to develop a framework that defines technology as a virus that penetrates the organism of an organization. The framework develops a new vocabulary, which can help in analyzing technologies and their negative effects on actors...... and organizations. In this paper, the virus theory is used to analyze a strategy process in an organization as an example of a technology. It shows how the strategy over time creates a memory loss, where the managers who are exposed to the virus forget their critique of the new strategy concept. The article also...... shows how resistant can be understood as being immune to a virus, since the strategy concepts bears resemblance to a former strategy concept. The article also argues that there should be more focus on the negative impacts of management tool and especially how organizations and managers are dealing...

Plant virus sensitivity to gamma irradiation

International Nuclear Information System (INIS)

Gyoergyne Czeck, B.

1979-01-01

Preliminary experiments for prevention were conducted with weakened plant viruses, namely with Arabis mosaic virus isolated from strawberries and tobacco mosaic virus. Treatment 24 hours prior to the infection with the radiation-weakened virus resulted in a 60-70% infection prevention. (author)

Unprecedented genomic diversity of RNA viruses in arthropods reveals the ancestry of negative-sense RNA viruses.

Science.gov (United States)

Li, Ci-Xiu; Shi, Mang; Tian, Jun-Hua; Lin, Xian-Dan; Kang, Yan-Jun; Chen, Liang-Jun; Qin, Xin-Cheng; Xu, Jianguo; Holmes, Edward C; Zhang, Yong-Zhen

2015-01-29

Although arthropods are important viral vectors, the biodiversity of arthropod viruses, as well as the role that arthropods have played in viral origins and evolution, is unclear. Through RNA sequencing of 70 arthropod species we discovered 112 novel viruses that appear to be ancestral to much of the documented genetic diversity of negative-sense RNA viruses, a number of which are also present as endogenous genomic copies. With this greatly enriched diversity we revealed that arthropods contain viruses that fall basal to major virus groups, including the vertebrate-specific arenaviruses, filoviruses, hantaviruses, influenza viruses, lyssaviruses, and paramyxoviruses. We similarly documented a remarkable diversity of genome structures in arthropod viruses, including a putative circular form, that sheds new light on the evolution of genome organization. Hence, arthropods are a major reservoir of viral genetic diversity and have likely been central to viral evolution.

Protection against myxomatosis and rabbit viral hemorrhagic disease with recombinant myxoma viruses expressing rabbit hemorrhagic disease virus capsid protein.

Science.gov (United States)

Bertagnoli, S; Gelfi, J; Le Gall, G; Boilletot, E; Vautherot, J F; Rasschaert, D; Laurent, S; Petit, F; Boucraut-Baralon, C; Milon, A

1996-08-01

Two myxoma virus-rabbit hemorrhagic disease virus (RHDV) recombinant viruses were constructed with the SG33 strain of myxoma virus to protect rabbits against myxomatosis and rabbit viral hemorrhagic disease. These recombinant viruses expressed the RHDV capsid protein (VP60). The recombinant protein, which is 60 kDa in size, was antigenic, as revealed by its reaction in immunoprecipitation with antibodies raised against RHDV. Both recombinant viruses induced high levels of RHDV- and myxoma virus-specific antibodies in rabbits after immunization. Inoculations by the intradermal route protected animals against virulent RHDV and myxoma virus challenges.

Prevalence of Human Parainfluenza Viruses and Noroviruses Genomes on Office Fomites.

Science.gov (United States)

Stobnicka, Agata; Gołofit-Szymczak, Małgorzata; Wójcik-Fatla, Angelina; Zając, Violetta; Korczyńska-Smolec, Joanna; Górny, Rafał L

2018-06-01

The aim of this study was to evaluate the potential role of office fomites in respiratory (human parainfluenza virus 1-HPIV1, human parainfluenza virus 3-HPIV3) and enteric (norovirus GI-NoV GI, norovirus GII-NoV GII) viruses transmission by assessing the occurrence of these viruses on surfaces in office buildings. Between 2016 and 2017, a total of 130 surfaces from open-space and non-open-space rooms in office buildings located in one city were evaluated for HPIV1, HPIV3, NoV GI, and NoV GII viral RNA presence. Detection of viruses was performed by RT-qPCR method. Study revealed 27 positive samples, among them 59.3% were HPIV3-positive, 25.9% HPIV1-positive, and 14.8% NoV GII-positive. All tested surfaces were NoV GI-negative. Statistical analysis of obtained data showed that the surfaces of office equipment including computer keyboards and mice, telephones, and desktops were significantly more contaminated with respiratory viruses than the surfaces of building equipment elements such as door handles, light switches, or ventilation tracts (χ 2 p = 0.006; Fisher's Exact p = 0.004). All examined surfaces were significantly more contaminated with HPIVs than NoVs (χ 2 p = 0.002; Fisher's Exact p = 0.003). Office fomites in open-space rooms were more often contaminated with HPIVs than with NoVs (χ 2 p = 0.016; Fisher's Exact p = 0.013). The highest average concentration of HPIVs RNA copies was observed on telephones (1.66 × 10 2 copies/100 cm 2 ), while NoVs on the light switches (1.40 × 10 2 copies/100 cm 2 ). However, the Kruskal-Wallis test did not show statistically significant differences in concentration levels of viral RNA copies on surfaces between the all tested samples. This study unequivocally showed that individuals in office environment may have contact with both respiratory and enteric viral particles present on frequently touched surfaces.

A Literature Review of Zika Virus.

Science.gov (United States)

Plourde, Anna R; Bloch, Evan M

2016-07-01

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

Tobacco ringspot virus

Science.gov (United States)

Tobacco ringspot virus (TRSV), and its vector, the dagger nematodes (Xiphinema americanum and related species) are widely distributed throughout the world. Cucumber, melon, and watermelon are particularly affected by TRSV. Symptoms can vary with plant age, the strain of the virus, and environment...

Viruses affecting lentil (Lens culinaris Medik. in Greece; incidence and genetic variability of Bean leafroll virus and Pea enation mosaic virus

Directory of Open Access Journals (Sweden)

Elisavet K. CHATZIVASSILIOU

2016-07-01

Full Text Available In Greece, lentil (Lens culinaris Medik. crops are mainly established with non-certified seeds of local landraces, implying high risks for seed transmitted diseases. During April and May of the 2007–2012 growing seasons, surveys were conducted in eight regions of Greece (Attiki, Evros, Fthiotida, Korinthos, Kozani, Larissa, Lefkada and Viotia to monitor virus incidence in lentil fields. A total of 1216 lentil samples, from plants exhibiting symptoms suggestive of virus infection, were analyzed from 2007 to 2009, using tissue-blot immunoassays (TBIA. Pea seed-borne mosaic virus (PSbMV overall incidence was 4.9%, followed by Alfalfa mosaic virus (AMV (2.4% and Bean yellow mosaic virus (BYMV (1.0%. When 274 of the samples were tested for the presence of luteoviruses, 38.8% were infected with Bean leafroll virus (BLRV. Since BLRV was not identified in the majority of the samples collected from 2007 to 2009, representative symptomatic plants (360 samples were collected in further surveys performed from 2010 to 2012 and tested by ELISA. Two viruses prevailed in those samples: BLRV (36.1% was associated with stunting, yellowing, and reddening symptoms and Pea enation mosaic virus-1 (PEMV-1 (35.0% was associated with mosaic and mottling symptoms. PSbMV (2.2%, AMV (2.2%, BYMV (3.9% and CMV (2.8% were also detected. When the molecular variability was analyzed for representative isolates, collected from the main Greek lentil production areas, five BLRV isolates showed 95% identity for the coat protein (CP gene and 99% for the 3’ end region. Three Greek PEMV isolates co-clustered with an isolate from Germany when their CP sequence was compared with isolates with no mutation in the aphid transmission gene. Overall, limited genetic variability was detected among Greek isolates of BLRV and PEMV.

Virus-neutralizing antibody response of mice to consecutive infection with human and avian influenza A viruses.

Science.gov (United States)

Janulíková, J; Stropkovská, A; Bobišová, Z; Košík, I; Mucha, V; Kostolanský, F; Varečková, E

2015-06-01

In this work we simulated in a mouse model a naturally occurring situation of humans, who overcame an infection with epidemic strains of influenza A, and were subsequently exposed to avian influenza A viruses (IAV). The antibody response to avian IAV in mice previously infected with human IAV was analyzed. We used two avian IAV (A/Duck/Czechoslovakia/1956 (H4N6) and the attenuated virus rA/Viet Nam/1203-2004 (H5N1)) as well as two human IAV isolates (virus A/Mississippi/1/1985 (H3N2) of medium virulence and A/Puerto Rico/8/1934 (H1N1) of high virulence). Two repeated doses of IAV of H4 or of H5 virus elicited virus-specific neutralizing antibodies in mice. Exposure of animals previously infected with human IAV (of H3 or H1 subtype) to IAV of H4 subtype led to the production of antibodies neutralizing H4 virus in a level comparable with the level of antibodies against the human IAV used for primary infection. In contrast, no measurable levels of virus-neutralizing (VN) antibodies specific to H5 virus were detected in mice infected with H5 virus following a previous infection with human IAV. In both cases the secondary infection with avian IAV led to a significant increase of the titer of VN antibodies specific to the corresponding human virus used for primary infection. Moreover, cross-reactive HA2-specific antibodies were also induced by sequential infection. By virtue of these results we suggest that the differences in the ability of avian IAV to induce specific antibodies inhibiting virus replication after previous infection of mice with human viruses can have an impact on the interspecies transmission and spread of avian IAV in the human population.

Differential diagnosis of feline leukemia virus subgroups using pseudotype viruses expressing green fluorescent protein.

Science.gov (United States)

Nakamura, Megumi; Sato, Eiji; Miura, Tomoyuki; Baba, Kenji; Shimoda, Tetsuya; Miyazawa, Takayuki

2010-06-01

Feline leukemia virus (FeLV) is classified into three receptor interference subgroups, A, B and C. In this study, to differentiate FeLV subgroups, we developed a simple assay system using pseudotype viruses expressing green fluorescent protein (GFP). We prepared gfp pseudotype viruses, named gfp(FeLV-A), gfp(FeLV-B) and gfp(FeLV-C) harboring envelopes of FeLV-A, B and C, respectively. The gfp pseudotype viruses completely interfered with the same subgroups of FeLV reference strains on FEA cells (a feline embryonic fibroblast cell line). We also confirmed that the pseudotype viruses could differentiate FeLV subgroups in field isolates. The assay will be useful for differential diagnosis of FeLV subgroups in veterinary diagnostic laboratories in the future.

Interventions Against West Nile Virus, Rift Valley Fever Virus, and Crimean-Congo Hemorrhagic Fever Virus: Where Are We?

NARCIS (Netherlands)

Kortekaas, J.A.; Ergonul, O.; Moormann, R.J.M.

2010-01-01

ARBO-ZOONET is an international network financed by the European Commission's seventh framework program. The major goal of this initiative is capacity building for the control of emerging viral vector-borne zoonotic diseases, with a clear focus on West Nile virus, Rift Valley fever virus, and

West Nile virus: North American experience

Science.gov (United States)

Hofmeister, Erik K.

2011-01-01

West Nile virus, a mosquito-vectored flavivirus of the Japanese encephalitis serogroup, was first detected in North America following an epizootic in the New York City area in 1999. In the intervening 11 years since the arrival of the virus in North America, it has crossed the contiguous USA, entered the Canadian provinces bordering the USA, and has been reported in the Caribbean islands, Mexico, Central America and, more recently, South America. West Nile virus has been reported in over 300 species of birds in the USA and has caused the deaths of thousands of birds, local population declines of some avian species, the clinical illness and deaths of thousands of domestic horses, and the clinical disease in over 30 000 Americans and the deaths of over 1000. Prior to the emergence of West Nile virus in North America, St. Louis encephalitis virus and Dengue virus were the only other known mosquito-transmitted flaviviruses in North America capable of causing human disease. This review will discuss the North American experience with mosquito-borne flavivirus prior to the arrival of West Nile virus, the entry and spread of West Nile virus in North America, effects on wild bird populations, genetic changes in the virus, and the current state of West Nile virus transmission.

Drosophila Nora virus capsid proteins differ from those of other picorna-like viruses.

Science.gov (United States)

Ekström, Jens-Ola; Habayeb, Mazen S; Srivastava, Vaibhav; Kieselbach, Thomas; Wingsle, Gunnar; Hultmark, Dan

2011-09-01

The recently discovered Nora virus from Drosophila melanogaster is a single-stranded RNA virus. Its published genomic sequence encodes a typical picorna-like cassette of replicative enzymes, but no capsid proteins similar to those in other picorna-like viruses. We have now done additional sequencing at the termini of the viral genome, extending it by 455 nucleotides at the 5' end, but no more coding sequence was found. The completeness of the final 12,333-nucleotide sequence was verified by the production of infectious virus from the cloned genome. To identify the capsid proteins, we purified Nora virus particles and analyzed their proteins by mass spectrometry. Our results show that the capsid is built from three major proteins, VP4A, B and C, encoded in the fourth open reading frame of the viral genome. The viral particles also contain traces of a protein from the third open reading frame, VP3. VP4A and B are not closely related to other picorna-like virus capsid proteins in sequence, but may form similar jelly roll folds. VP4C differs from the others and is predicted to have an essentially α-helical conformation. In a related virus, identified from EST database sequences from Nasonia parasitoid wasps, VP4C is encoded in a separate open reading frame, separated from VP4A and B by a frame-shift. This opens a possibility that VP4C is produced in non-equimolar quantities. Altogether, our results suggest that the Nora virus capsid has a different protein organization compared to the order Picornavirales. Copyright © 2011 Elsevier B.V. All rights reserved.

Global Mapping of O-Glycosylation of Varicella Zoster Virus, Human Cytomegalovirus, and Epstein-Barr Virus*

Science.gov (United States)

Bagdonaite, Ieva; Nordén, Rickard; Joshi, Hiren J.; King, Sarah L.; Vakhrushev, Sergey Y.; Olofsson, Sigvard; Wandall, Hans H.

2016-01-01

Herpesviruses are among the most complex and widespread viruses, infection and propagation of which depend on envelope proteins. These proteins serve as mediators of cell entry as well as modulators of the immune response and are attractive vaccine targets. Although envelope proteins are known to carry glycans, little is known about the distribution, nature, and functions of these modifications. This is particularly true for O-glycans; thus we have recently developed a “bottom up” mass spectrometry-based technique for mapping O-glycosylation sites on herpes simplex virus type 1. We found wide distribution of O-glycans on herpes simplex virus type 1 glycoproteins and demonstrated that elongated O-glycans were essential for the propagation of the virus. Here, we applied our proteome-wide discovery platform for mapping O-glycosites on representative and clinically significant members of the herpesvirus family: varicella zoster virus, human cytomegalovirus, and Epstein-Barr virus. We identified a large number of O-glycosites distributed on most envelope proteins in all viruses and further demonstrated conserved patterns of O-glycans on distinct homologous proteins. Because glycosylation is highly dependent on the host cell, we tested varicella zoster virus-infected cell lysates and clinically isolated virus and found evidence of consistent O-glycosites. These results present a comprehensive view of herpesvirus O-glycosylation and point to the widespread occurrence of O-glycans in regions of envelope proteins important for virus entry, formation, and recognition by the host immune system. This knowledge enables dissection of specific functional roles of individual glycosites and, moreover, provides a framework for design of glycoprotein vaccines with representative glycosylation. PMID:27129252

Iguana Virus, a Herpes-Like Virus Isolated from Cultured Cells of a Lizard, Iguana iguana

Science.gov (United States)

Clark, H. Fred; Karzon, David T.

1972-01-01

An agent cytopathic for Terrapene and Iguana cell cultures was isolated from spontaneously degenerating cell cultures prepared from a green iguana (Iguana iguana). The agent, designated iguana virus, caused a cytopathic effect (CPE) of a giant cell type, with eosinophilic inclusions commonly observed within giant cell nuclei. Incubation temperature had a marked effect on CPE and on virus release from infected cells. Within the range of 23 to 36 C, low temperatures favored CPE characterized by cytolysis and small giant cell formation, and significant virus release was observed. At warmer temperatures, a purely syncytial type of CPE and total absence of released virus were noted. A unique type of hexagonal eosinophilic cytoplasmic inclusion was observed within syncytia of infected Terrapene cell cultures incubated at 36 C. In vivo studies revealed no evidence of pathogenicity of iguana virus for suckling mice, embryonated hen's eggs, or several species of reptiles and amphibians. Inoculation of iguana virus into young iguanas consistently caused infection that was “unmasked” only when cell cultures were prepared directly from the infected animal. Filtration studies revealed a virion size of >100 nm and Iguana virus is ether-sensitive and, as presumptively indicated by studies of inhibition by bromodeoxyuridine, possesses a deoxyribonucleic type of nucleic acid. The virus characteristics described, as well as electron microscopy observations described in a separate report, indicate that iguana virus is a member of the herpesvirus group. Images PMID:4344303

Characterization of Ebola virus entry by using pseudotyped viruses: identification of receptor-deficient cell lines.

Science.gov (United States)

Wool-Lewis, R J; Bates, P

1998-04-01

Studies analyzing Ebola virus replication have been severely hampered by the extreme pathogenicity of this virus. To permit analysis of the host range and function of the Ebola virus glycoprotein (Ebo-GP), we have developed a system for pseudotyping these glycoproteins into murine leukemia virus (MLV). This pseudotyped virus, MLV(Ebola), can be readily concentrated to titers which exceed 5 x 10(6) infectious units/ml and is effectively neutralized by antibodies specific for Ebo-GP. Analysis of MLV(Ebola) infection revealed that the host range conferred by Ebo-GP is very broad, extending to cells of a variety of species. Notably, all lymphoid cell lines tested were completely resistant to infection; we speculate that this is due to the absence of a cellular receptor for Ebo-GP on B and T cells. The generation of high-titer MLV(Ebola) pseudotypes will be useful for the analysis of immune responses to Ebola virus infection, development of neutralizing antibodies, analysis of glycoprotein function, and isolation of the cellular receptor(s) for the Ebola virus.

Solanum americanum: reservoir for Potato virus Y and Cucumber mosaic virus in sweet pepper crops

Directory of Open Access Journals (Sweden)

Monika Fecury Moura

2014-03-01

Full Text Available Weeds can act as important reservoirs for viruses. Solanum americanum (Black nightshade is a common weed in Brazil and samples showing mosaic were collected from sweet pepper crops to verify the presence of viruses. One sample showed mixed infection between Cucumber mosaic virus (CMV and Potato virus Y (PVY and one sample showed simple infection by PVY. Both virus species were transmitted by plant extract and caused mosaic in tomato (Solanum lycopersicum cv. Santa Clara, sweet pepper (Capsicum annuum cv. Magda, Nicotiana benthamiana and N. tabaccum TNN, and local lesions on Chenopodium quinoa, C. murale and C. amaranticolor. The coat protein sequences for CMV and PVY found in S. americanum are phylogenetically more related to isolates from tomato. We conclude that S. americanum can act as a reservoir for different viruses during and between sweet pepper crop seasons.

Archaeal Viruses: Diversity, Replication, and Structure.

Science.gov (United States)

Dellas, Nikki; Snyder, Jamie C; Bolduc, Benjamin; Young, Mark J

2014-11-01

The Archaea-and their viruses-remain the most enigmatic of life's three domains. Once thought to inhabit only extreme environments, archaea are now known to inhabit diverse environments. Even though the first archaeal virus was described over 40 years ago, only 117 archaeal viruses have been discovered to date. Despite this small number, these viruses have painted a portrait of enormous morphological and genetic diversity. For example, research centered around the various steps of the archaeal virus life cycle has led to the discovery of unique mechanisms employed by archaeal viruses during replication, maturation, and virion release. In many instances, archaeal virus proteins display very low levels of sequence homology to other proteins listed in the public database, and therefore, structural characterization of these proteins has played an integral role in functional assignment. These structural studies have not only provided insights into structure-function relationships but have also identified links between viruses across all three domains of life.

Top 10 plant viruses in molecular plant pathology.

Science.gov (United States)

Scholthof, Karen-Beth G; Adkins, Scott; Czosnek, Henryk; Palukaitis, Peter; Jacquot, Emmanuel; Hohn, Thomas; Hohn, Barbara; Saunders, Keith; Candresse, Thierry; Ahlquist, Paul; Hemenway, Cynthia; Foster, Gary D

2011-12-01

Many scientists, if not all, feel that their particular plant virus should appear in any list of the most important plant viruses. However, to our knowledge, no such list exists. The aim of this review was to survey all plant virologists with an association with Molecular Plant Pathology and ask them to nominate which plant viruses they would place in a 'Top 10' based on scientific/economic importance. The survey generated more than 250 votes from the international community, and allowed the generation of a Top 10 plant virus list for Molecular Plant Pathology. The Top 10 list includes, in rank order, (1) Tobacco mosaic virus, (2) Tomato spotted wilt virus, (3) Tomato yellow leaf curl virus, (4) Cucumber mosaic virus, (5) Potato virus Y, (6) Cauliflower mosaic virus, (7) African cassava mosaic virus, (8) Plum pox virus, (9) Brome mosaic virus and (10) Potato virus X, with honourable mentions for viruses just missing out on the Top 10, including Citrus tristeza virus, Barley yellow dwarf virus, Potato leafroll virus and Tomato bushy stunt virus. This review article presents a short review on each virus of the Top 10 list and its importance, with the intent of initiating discussion and debate amongst the plant virology community, as well as laying down a benchmark, as it will be interesting to see in future years how perceptions change and which viruses enter and leave the Top 10. © 2011 The Authors. Molecular Plant Pathology © 2011 BSPP and Blackwell Publishing Ltd.

Selective host range restriction of goat cells for recombinant murine leukemia virus and feline leukemia virus type A.

OpenAIRE

Fischinger, P J; Thiel, H J; Blevins, C S; Dunlop, N M

1981-01-01

We isolated a strain of normal goat fibroblasts which was uniquely selective in that it allowed the replication of xenotropic murine leukemia virus but not polytropic recombinant murine leukemia virus. In addition, feline leukemia virus type A replication was severely diminished in these goat cells, whereas feline leukemia virus type B and feline endogenous RD114-CCC viruses replicated efficiently. No other known cells exhibit this pattern of virus growth restriction. These goat cells allow t...

Recent progress in computational approaches to studying the M2 proton channel and its implication to drug design against influenza viruses.

Science.gov (United States)

Du, Qi-Shi; Huang, Ri-Bo

2012-05-01

For quite a long period of time in history, many intense efforts have been made to determine the 3D (three-dimensional) structure of the M2 proton channel. The reason why the M2 proton channel has attracted so many attentions is because (1) it is the key for really understanding the life cycle of influenza viruses, and (2) it is indispensable for conducting rational drug design against the flu viruses. Recently, the long-sough 3D structures of the M2 proton channels for both influenza A and B viruses were consecutively successfully determined by the high-resolution NMR spectroscopy (Schnell J.R. and Chou, J.J., Nature, 2008, 451: 591-595; Wang, J., Pielak, R.M., McClintock, M.A., and Chou, J.J., Nature Structural & Molecular Biology, 2009,16: 1267-1271). Such a milestone work has provided a solid structural basis for in-depth understanding the action mechanism of the M2 channel and rationally designing effective drugs against influenza viruses. This review is devoted to, with the focus on the M2 proton channel of influenza A, addressing a series of relevant problems, such as how to correctly understand the novel allosteric inhibition mechanism inferred from the NMR structure that is completely different from the traditional view, what the possible impacts are to the previous functional studies in this area, and what kind of new strategy can be stimulated for drug development against influenza.

Reassortant H1N1 influenza virus vaccines protect pigs against pandemic H1N1 influenza virus and H1N2 swine influenza virus challenge.

Science.gov (United States)

Yang, Huanliang; Chen, Yan; Shi, Jianzhong; Guo, Jing; Xin, Xiaoguang; Zhang, Jian; Wang, Dayan; Shu, Yuelong; Qiao, Chuanling; Chen, Hualan

2011-09-28

Influenza A (H1N1) virus has caused human influenza outbreaks in a worldwide pandemic since April 2009. Pigs have been found to be susceptible to this influenza virus under experimental and natural conditions, raising concern about their potential role in the pandemic spread of the virus. In this study, we generated a high-growth reassortant virus (SC/PR8) that contains the hemagglutinin (HA) and neuraminidase (NA) genes from a novel H1N1 isolate, A/Sichuan/1/2009 (SC/09), and six internal genes from A/Puerto Rico/8/34 (PR8) virus, by genetic reassortment. The immunogenicity and protective efficacy of this reassortant virus were evaluated at different doses in a challenge model using a homologous SC/09 or heterologous A/Swine/Guangdong/1/06(H1N2) virus (GD/06). Two doses of SC/PR8 virus vaccine elicited high-titer serum hemagglutination inhibiting (HI) antibodies specific for the 2009 H1N1 virus and conferred complete protection against challenge with either SC/09 or GD/06 virus, with reduced lung lesions and viral shedding in vaccine-inoculated animals compared with non-vaccinated control animals. These results indicated for the first time that a high-growth SC/PR8 reassortant H1N1 virus exhibits properties that are desirable to be a promising vaccine candidate for use in swine in the event of a pandemic H1N1 influenza. Copyright © 2011 Elsevier B.V. All rights reserved.

Recombinant Vaccinia Virus: Immunization against Multiple Pathogens

Science.gov (United States)

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

1985-09-01

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

Implementasi Cloud Computing Menggunakan Openvz dalam Perkuliahan Praktikum Sistem Operasi

Directory of Open Access Journals (Sweden)

Muhammad Arif Fadhly Ridha

2016-03-01

Full Text Available Cloud computing is the latest technology that are built using virtualization service that makes server becomes abstract and can be accessed from anywhere. One of the virtualization technology that can be used to build a cloud network is OpenVZ on Linux operating system. Currently the lab lectures operating systems generally use desktop virtualization software such as VMWare or Vritualbox that often cause problems such as the threat of viruses, loss of data and configuration. Therefore, a centralized system using cloud computing and virtualization designed and implemented so that such problems can be avoided. Cloud Computing systems are made using OpenVZ so that each student will have a virtual server account on the cloud system. Results from the research showed that the use of Cloud Computing in the lab can be applied to operating system course and can solve error plobems than using Virtual Machine Application.

Zika Virus: An Emergent Neuropathological Agent

Science.gov (United States)

White, Martyn K.; Wollebo, Hassen S.; Beckham, J. David; Tyler, Kenneth L.; Khalili, Kamel

2016-01-01

The emergence of Zika virus in the Americas has followed a pattern that is familiar from earlier epidemics of other viruses, where a new disease is introduced into a human population and then spreads rapidly with important public health consequences. In the case of Zika virus, an accumulating body of recent evidence implicates the virus in the etiology of serious pathologies of the human nervous system, that is, the occurrence of microcephaly in neonates and Guillain–Barré syndrome in adults. Zika virus is an arbovirus (arthropod-borne virus) and a member of the family Flaviviridae, genus Flavivirus. Zika virions are enveloped and icosahedral, and contain a nonsegmented, single-stranded, positive-sense RNA genome, which encodes 3 structural and 7 nonstructural proteins that are expressed as a single polyprotein that undergoes cleavage. Zika genomic RNA replicates in the cytoplasm of infected host cells. Zika virus was first detected in 1947 in the blood of a febrile monkey in Uganda’s Zika Forest and in crushed suspensions of the Aedes mosquito, which is one of the vectors for Zika virus. The virus remained obscure, with a few human cases confined to Africa and Asia. There are two lineages of the Zika virus, African and Asian, with the Asian strain causing outbreaks in Micronesia in 2007 and French Polynesia in 2013–2014. From here, the virus spread to Brazil with the first report of autochthonous Zika transmission in the Americas in March 2015. The rapid advance of the virus in the Americas and its likely association with microcephaly and Guillain–Barré syndrome make Zika an urgent public health concern. PMID:27464346

Viral coinfection is shaped by host ecology and virus-virus interactions across diverse microbial taxa and environments.

Science.gov (United States)

Díaz-Muñoz, Samuel L

2017-01-01

Infection of more than one virus in a host, coinfection, is common across taxa and environments. Viral coinfection can enable genetic exchange, alter the dynamics of infections, and change the course of viral evolution. Yet, a systematic test of the factors explaining variation in viral coinfection across different taxa and environments awaits completion. Here I employ three microbial data sets of virus-host interactions covering cross-infectivity, culture coinfection, and single-cell coinfection (total: 6,564 microbial hosts, 13,103 viruses) to provide a broad, comprehensive picture of the ecological and biological factors shaping viral coinfection. I found evidence that ecology and virus-virus interactions are recurrent factors shaping coinfection patterns. Host ecology was a consistent and strong predictor of coinfection across all three data sets: cross-infectivity, culture coinfection, and single-cell coinfection. Host phylogeny or taxonomy was a less consistent predictor, being weak or absent in the cross-infectivity and single-cell coinfection models, yet it was the strongest predictor in the culture coinfection model. Virus-virus interactions strongly affected coinfection. In the largest test of superinfection exclusion to date, prophage sequences reduced culture coinfection by other prophages, with a weaker effect on extrachromosomal virus coinfection. At the single-cell level, prophage sequences eliminated coinfection. Virus-virus interactions also increased culture coinfection with ssDNA-dsDNA coinfections >2× more likely than ssDNA-only coinfections. The presence of CRISPR spacers was associated with a ∼50% reduction in single-cell coinfection in a marine bacteria, despite the absence of exact spacer matches in any active infection. Collectively, these results suggest the environment bacteria inhabit and the interactions among surrounding viruses are two factors consistently shaping viral coinfection patterns. These findings highlight the role of

Epidemic of cell phone virus

Science.gov (United States)

Wang, Pu; González, Marta; Barabási, Albert-László.

2008-03-01

Standard operating systems and Bluetooth technology will be a trend for future cell phone features. These will enable cell phone viruses to spread either through SMS or by sending Bluetooth requests when cell phones are physically close enough. The difference in spreading methods gives these two types of viruses' different epidemiological characteristics. SMS viruses' spread is mainly based on people's social connections, whereas the spreading of Bluetooth viruses is affected by people's mobility patterns and population distribution. Using cell phone data recording calls, SMS and locations of more than 6 million users, we study the spread of SMS and Bluetooth viruses and characterize how the social network and the mobility of mobile phone users affect such spreading processes.

SARS – virus jumps species

Indian Academy of Sciences (India)

SARS – virus jumps species. Coronavirus reshuffles genes; Rotteir et al, Rotterdam showed the virus to jump from cats to mouse cells after single gene mutation ? Human disease due to virus jumping from wild or domestic animals; Present favourite animal - the cat; - edible or domestic.

Avian influenza virus

Science.gov (United States)

Avian influenza virus (AIV) is type A influenza that is adapted to avian host species. Although the virus can be isolated from numerous avian species, the natural host reservoir species are dabbling ducks, shorebirds and gulls. Domestic poultry species (poultry being defined as birds that are rais...

ISCB Ebola Award for Important Future Research on the Computational Biology of Ebola Virus

OpenAIRE

Karp, P.D.; Berger, B.; Kovats, D.; Lengauer, T.; Linial, M.; Sabeti, P.; Hide, W.; Rost, B.

2015-01-01

Speed is of the essence in combating Ebola; thus, computational approaches should form a significant component of Ebola research. As for the development of any modern drug, computational biology is uniquely positioned to contribute through comparative analysis of the genome sequences of Ebola strains as well as 3-D protein modeling. Other computational approaches to Ebola may include large-scale docking studies of Ebola proteins with human proteins and with small-molecule libraries, computati...

Treatability evaluation of membrane technique by virus. Maku shori ni okeru shorisei hyoka to shite no virus

Energy Technology Data Exchange (ETDEWEB)

Yano, K. (Tokyo Metropolitan Research Lab. of Public Health, Tokyo (Japan))

1990-08-10

Concerning a high level treating method of regeneration of sewage water, there are methods of coagulation/precipitation, sand filtering and ozone treatment in addition to the conventional active sludge method. However, none of these methods are perfect from the viewpoint of virus. A film treating method to remove micro-organisms in water is twofold, i.e., microfiltration and reverse osmosis. For such filter treatments, polio virus is most suited as an experimental index for conducting an assessment of the treating ability of viruses. The reasons are as follows: 1. It is the smallest virus among the viruses which are mixed in the water systems. 2. Polio virus is always detected in the study of actual conditions of the viruses contained in the sewage waters. 3. It involves less danger in handling because there are vaccines which are made less poisonous. 4. Separation and quantification of viruses is easily conducted by means of cultured cells. 8 refs., 1 fig., 7 tabs.

[Epidemiologic aspects of human immunodeficiency virus and hepatitis virus infections].

Science.gov (United States)

Diarra, M; Konate, A; Minta, D; Sounko, A; Dembele, M; Toure, C S; Kalle, A; Traore, H H; Maiga, M Y

2006-01-01

In order to determinate the prevalence of hepatitis B virus and hepatitis C virus among patients infected by the HIV, We realized a transverse survey case--control in hepato-gastro-enterological ward and serology unity of National Institute of Research in Public health (INRSP). Our sample was constituted with 100 patients HIV positive compared to 100 controls HIV negative. The viral markers research has been made by methods immuno-enzymatiqueses of ELISA 3rd generation. Tests permitted to get the following results: Hepatitis B surface antigen (HBs Ag) was positive among 21% with patients HIV positive versus 23% among control (p = 0,732); Antibody to hepatitis C virus (anti-HCV ab) was present among 23% with patients HIV positive versus 0% among control (p <0,05). Female was predominant among co-infections patient, but without statistic link (p = 0,9 and p = 0,45); The co-infection HBV- HCV was significatively linked to age beyond 40 years (p = 0,0005). Co-infections with HIV infection and hepatitis virus are not rare and deserve to be investigated.

Host-Specific and Segment-Specific Evolutionary Dynamics of Avian and Human Influenza A Viruses: A Systematic Review

KAUST Repository

Kim, Kiyeon

2016-01-13

Understanding the evolutionary dynamics of influenza viruses is essential to control both avian and human influenza. Here, we analyze host-specific and segment-specific Tajima’s D trends of influenza A virus through a systematic review using viral sequences registered in the National Center for Biotechnology Information. To avoid bias from viral population subdivision, viral sequences were stratified according to their sampling locations and sampling years. As a result, we obtained a total of 580 datasets each of which consists of nucleotide sequences of influenza A viruses isolated from a single population of hosts at a single sampling site within a single year. By analyzing nucleotide sequences in the datasets, we found that Tajima’s D values of viral sequences were different depending on hosts and gene segments. Tajima’s D values of viruses isolated from chicken and human samples showed negative, suggesting purifying selection or a rapid population growth of the viruses. The negative Tajima’s D values in rapidly growing viral population were also observed in computer simulations. Tajima’s D values of PB2, PB1, PA, NP, and M genes of the viruses circulating in wild mallards were close to zero, suggesting that these genes have undergone neutral selection in constant-sized population. On the other hand, Tajima’s D values of HA and NA genes of these viruses were positive, indicating HA and NA have undergone balancing selection in wild mallards. Taken together, these results indicated the existence of unknown factors that maintain viral subtypes in wild mallards.

Prediction of protein-protein interactions in dengue virus coat proteins guided by low resolution cryoEM structures

Directory of Open Access Journals (Sweden)

Srinivasan Narayanaswamy

2010-06-01

Full Text Available Abstract Background Dengue virus along with the other members of the flaviviridae family has reemerged as deadly human pathogens. Understanding the mechanistic details of these infections can be highly rewarding in developing effective antivirals. During maturation of the virus inside the host cell, the coat proteins E and M undergo conformational changes, altering the morphology of the viral coat. However, due to low resolution nature of the available 3-D structures of viral assemblies, the atomic details of these changes are still elusive. Results In the present analysis, starting from Cα positions of low resolution cryo electron microscopic structures the residue level details of protein-protein interaction interfaces of dengue virus coat proteins have been predicted. By comparing the preexisting structures of virus in different phases of life cycle, the changes taking place in these predicted protein-protein interaction interfaces were followed as a function of maturation process of the virus. Besides changing the current notion about the presence of only homodimers in the mature viral coat, the present analysis indicated presence of a proline-rich motif at the protein-protein interaction interface of the coat protein. Investigating the conservation status of these seemingly functionally crucial residues across other members of flaviviridae family enabled dissecting common mechanisms used for infections by these viruses. Conclusions Thus, using computational approach the present analysis has provided better insights into the preexisting low resolution structures of virus assemblies, the findings of which can be made use of in designing effective antivirals against these deadly human pathogens.

Host-Specific and Segment-Specific Evolutionary Dynamics of Avian and Human Influenza A Viruses: A Systematic Review

KAUST Repository

Kim, Kiyeon; Omori, Ryosuke; Ueno, Keisuke; Iida, Sayaka; Ito, Kimihito

2016-01-01

Understanding the evolutionary dynamics of influenza viruses is essential to control both avian and human influenza. Here, we analyze host-specific and segment-specific Tajima’s D trends of influenza A virus through a systematic review using viral sequences registered in the National Center for Biotechnology Information. To avoid bias from viral population subdivision, viral sequences were stratified according to their sampling locations and sampling years. As a result, we obtained a total of 580 datasets each of which consists of nucleotide sequences of influenza A viruses isolated from a single population of hosts at a single sampling site within a single year. By analyzing nucleotide sequences in the datasets, we found that Tajima’s D values of viral sequences were different depending on hosts and gene segments. Tajima’s D values of viruses isolated from chicken and human samples showed negative, suggesting purifying selection or a rapid population growth of the viruses. The negative Tajima’s D values in rapidly growing viral population were also observed in computer simulations. Tajima’s D values of PB2, PB1, PA, NP, and M genes of the viruses circulating in wild mallards were close to zero, suggesting that these genes have undergone neutral selection in constant-sized population. On the other hand, Tajima’s D values of HA and NA genes of these viruses were positive, indicating HA and NA have undergone balancing selection in wild mallards. Taken together, these results indicated the existence of unknown factors that maintain viral subtypes in wild mallards.

Varroa destructor Macula-like virus, Lake Sinai virus and other new RNA viruses in wild bumblebee hosts (Bombus pascuorum, Bombus lapidarius and Bombus pratorum).

Science.gov (United States)

Parmentier, Laurian; Smagghe, Guy; de Graaf, Dirk C; Meeus, Ivan

2016-02-01

Pollinators such as bumblebees (Bombus spp.) are in decline worldwide which poses a threat not only for ecosystem biodiversity but also to human crop production services. One main cause of pollinator decline may be the infection and transmission of diseases including RNA viruses. Recently, new viruses have been discovered in honeybees, but information on the presence of these in wild bumblebees is largely not available. In this study, we investigated the prevalence of new RNA viruses in Bombus species, and can report for the first time Varroa destructor Macula-like virus (VdMLV) and Lake Sinai virus (LSV) infection in multiple wild bumblebee hosts of Bombus pascuorum, Bombus lapidarius and Bombus pratorum. We sampled in 4 locations in Flanders, Belgium. Besides, we confirmed Slow bee paralysis virus (SBPV) in wild bumblebees, but no positive samples were obtained for Big Sioux river virus (BSRV). Secondly, we screened for the influence of apiaries on the prevalence of these viruses. Our results indicated a location effect for the prevalence of VdMLV in Bombus species, with a higher prevalence in the proximity of honeybee apiaries mainly observed in one location. For LSV, the prevalence was not different in the proximity or at a 1.5 km-distance of apiaries, but we reported a different isolate with similarities to LSV-2 and "LSV-clade A" as described by Ravoet et al. (2015), which was detected both in Apis mellifera and Bombus species. In general, our results indicate the existence of a disease pool of new viruses that seems to be associated to a broad range of Apoidae hosts, including multiple Bombus species. Copyright © 2015 Elsevier Inc. All rights reserved.

A systems biology approach to predictive developmental neurotoxicity of a larvicide used in the prevention of Zika virus transmission

DEFF Research Database (Denmark)

Audouze, Karine; Taboureau, Olivier; Grandjean, Philippe

2018-01-01

The need to prevent developmental brain disorders has led to an increased interest in efficient neurotoxicity testing. When an epidemic of microcephaly occurred in Brazil, Zika virus infection was soon identified as the likely culprit. However, the pathogenesis appeared to be complex, and a larvi......The need to prevent developmental brain disorders has led to an increased interest in efficient neurotoxicity testing. When an epidemic of microcephaly occurred in Brazil, Zika virus infection was soon identified as the likely culprit. However, the pathogenesis appeared to be complex...... the potential developmental neurotoxicity, and we applied this method to examine the larvicide pyriproxyfen widely used in the prevention of Zika virus transmission. Our computational model covered a wide range of possible pathways providing mechanistic hypotheses between pyriproxyfen and neurological disorders...

Autophagy in Negative-Strand RNA Virus Infection

Directory of Open Access Journals (Sweden)

Yupeng Wang

2018-02-01

Full Text Available Autophagy is a homoeostatic process by which cytoplasmic material is targeted for degradation by the cell. Viruses have learned to manipulate the autophagic pathway to ensure their own replication and survival. Although much progress has been achieved in dissecting the interplay between viruses and cellular autophagic machinery, it is not well understood how the cellular autophagic pathway is utilized by viruses and manipulated to their own advantage. In this review, we briefly introduce autophagy, viral xenophagy and the interaction among autophagy, virus and immune response, then focus on the interplay between NS-RNA viruses and autophagy during virus infection. We have selected some exemplary NS-RNA viruses and will describe how these NS-RNA viruses regulate autophagy and the role of autophagy in NS-RNA viral replication and in immune responses to virus infection. We also review recent advances in understanding how NS-RNA viral proteins perturb autophagy and how autophagy-related proteins contribute to NS-RNA virus replication, pathogenesis and antiviral immunity.

Ebola virus host cell entry.

Science.gov (United States)

Sakurai, Yasuteru

2015-01-01

Ebola virus is an enveloped virus with filamentous structure and causes a severe hemorrhagic fever in human and nonhuman primates. Host cell entry is the first essential step in the viral life cycle, which has been extensively studied as one of the therapeutic targets. A virus factor of cell entry is a surface glycoprotein (GP), which is an only essential viral protein in the step, as well as the unique particle structure. The virus also interacts with a lot of host factors to successfully enter host cells. Ebola virus at first binds to cell surface proteins and internalizes into cells, followed by trafficking through endosomal vesicles to intracellular acidic compartments. There, host proteases process GPs, which can interact with an intracellular receptor. Then, under an appropriate circumstance, viral and endosomal membranes are fused, which is enhanced by major structural changes of GPs, to complete host cell entry. Recently the basic research of Ebola virus infection mechanism has markedly progressed, largely contributed by identification of host factors and detailed structural analyses of GPs. This article highlights the mechanism of Ebola virus host cell entry, including recent findings.

Outbreaks of Influenza A Virus in Farmed Mink (Neovison vison) in Denmark: Molecular characterization of the involved viruses

DEFF Research Database (Denmark)

Larsen, Lars Erik; Breum, Solvej Østergaard; Trebbien, Ramona

mink farms with respiratory symptoms. Full-genome sequencing showed that the virus was a human/swine reassortant, with the H and N gene most related to human H3N2 viruses circulating in 2005. The remaining 6 genes were most closely related to H1N2 influenza viruses circulating in Danish swine....... This virus had not previously been described in swine, mink nor humans. PCRs assays specifically targeting the new reassortant were developed and used to screen influenza positive samples from humans and swine in Denmark with negative results. Thus, there was no evidence that this virus had spread to humans...... or was circulating in Danish pigs. In 2010 and 2011, influenza virus was again diagnosed in diseased mink in a few farms. The genetic typing showed that the virus was similar to the pandemic H1N1 virus circulating in humans and swine. The H3N2 virus was not detected in 2010 and 2011. Taken together, these findings...

Detection of selected plant viruses by microarrays

OpenAIRE

HRABÁKOVÁ, Lenka

2013-01-01

The main aim of this master thesis was the simultaneous detection of four selected plant viruses ? Apple mosaic virus, Plum pox virus, Prunus necrotic ringspot virus and Prune harf virus, by microarrays. The intermediate step in the process of the detection was optimizing of multiplex polymerase chain reaction (PCR).

Ebola Virus

Directory of Open Access Journals (Sweden)

Anusha Rangare Lakshman

2015-09-01

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

A new looming of Zika virus

Institute of Scientific and Technical Information of China (English)

Nirav R Soni

2016-01-01

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

Tunable protease-activatable virus nanonodes.

Science.gov (United States)

Judd, Justin; Ho, Michelle L; Tiwari, Abhinav; Gomez, Eric J; Dempsey, Christopher; Van Vliet, Kim; Igoshin, Oleg A; Silberg, Jonathan J; Agbandje-McKenna, Mavis; Suh, Junghae

2014-05-27

We explored the unique signal integration properties of the self-assembling 60-mer protein capsid of adeno-associated virus (AAV), a clinically proven human gene therapy vector, by engineering proteolytic regulation of virus-receptor interactions such that processing of the capsid by proteases is required for infection. We find the transfer function of our engineered protease-activatable viruses (PAVs), relating the degree of proteolysis (input) to PAV activity (output), is highly nonlinear, likely due to increased polyvalency. By exploiting this dynamic polyvalency, in combination with the self-assembly properties of the virus capsid, we show that mosaic PAVs can be constructed that operate under a digital AND gate regime, where two different protease inputs are required for virus activation. These results show viruses can be engineered as signal-integrating nanoscale nodes whose functional properties are regulated by multiple proteolytic signals with easily tunable and predictable response surfaces, a promising development toward advanced control of gene delivery.

Virus detection and quantification using electrical parameters

Science.gov (United States)

Ahmad, Mahmoud Al; Mustafa, Farah; Ali, Lizna M.; Rizvi, Tahir A.

2014-10-01

Here we identify and quantitate two similar viruses, human and feline immunodeficiency viruses (HIV and FIV), suspended in a liquid medium without labeling, using a semiconductor technique. The virus count was estimated by calculating the impurities inside a defined volume by observing the change in electrical parameters. Empirically, the virus count was similar to the absolute value of the ratio of the change of the virus suspension dopant concentration relative to the mock dopant over the change in virus suspension Debye volume relative to mock Debye volume. The virus type was identified by constructing a concentration-mobility relationship which is unique for each kind of virus, allowing for a fast (within minutes) and label-free virus quantification and identification. For validation, the HIV and FIV virus preparations were further quantified by a biochemical technique and the results obtained by both approaches corroborated well. We further demonstrate that the electrical technique could be applied to accurately measure and characterize silica nanoparticles that resemble the virus particles in size. Based on these results, we anticipate our present approach to be a starting point towards establishing the foundation for label-free electrical-based identification and quantification of an unlimited number of viruses and other nano-sized particles.

Pepino mosaic virus

NARCIS (Netherlands)

Vlugt, van der R.A.A.

2009-01-01

Pepino mosaic virus (PepMV) is a relatively new plant virus that has become a signifi cant agronomical problem in a relatively short period of time. It is a member of the genus Potexvirus within the family Flexiviridae and is readily mechanically transmissible. It is capable of infecting tomato

Laboratory preparedness in EU/EEA countries for detection of novel avian influenza A(H7N9) virus, May 2013

Science.gov (United States)

Broberg, E; Pereyaslov, D; Struelens, M; Palm, D; Meijer, A; Ellis, J; Zambon, M; McCauley, J; Daniels, R

2015-01-01

Following human infections with novel avian influenza A(H7N9) viruses in China, the European Centre for Disease Prevention and Control, the World Health Organization (WHO) Regional Office for Europe and the European Reference Laboratory Network for Human Influenza (ERLI-Net) rapidly posted relevant information, including real-time RT-PCR protocols. An influenza RNA sequence-based computational assessment of detection capabilities for this virus was conducted in 32 national influenza reference laboratories in 29 countries, mostly WHO National Influenza Centres participating in the WHO Global Influenza Surveillance and Response System (GISRS). Twenty-seven countries considered their generic influenza A virus detection assay to be appropriate for the novel A(H7N9) viruses. Twenty-two countries reported having containment facilities suitable for its isolation and propagation. Laboratories in 27 countries had applied specific H7 real-time RT-PCR assays and 20 countries had N9 assays in place. Positive control virus RNA was provided by the WHO Collaborating Centre in London to 34 laboratories in 22 countries to allow evaluation of their assays. Performance of the generic influenza A virus detection and H7 and N9 subtyping assays was good in 24 laboratories in 19 countries. The survey showed that ERLI-Net laboratories had rapidly developed and verified good capability to detect the novel A(H7N9) influenza viruses. PMID:24507469

A recombinant chimeric La Crosse virus expressing the surface glycoproteins of Jamestown Canyon virus is immunogenic and protective against challenge with either parental virus in mice or monkeys.

Science.gov (United States)

Bennett, R S; Gresko, A K; Nelson, J T; Murphy, B R; Whitehead, S S

2012-01-01

La Crosse virus (LACV) and Jamestown Canyon virus (JCV), family Bunyaviridae, are mosquito-borne viruses that are endemic in North America and recognized as etiologic agents of encephalitis in humans. Both viruses belong to the California encephalitis virus serogroup, which causes 70 to 100 cases of encephalitis a year. As a first step in creating live attenuated viral vaccine candidates for this serogroup, we have generated a recombinant LACV expressing the attachment/fusion glycoproteins of JCV. The JCV/LACV chimeric virus contains full-length S and L segments derived from LACV. For the M segment, the open reading frame (ORF) of LACV is replaced with that derived from JCV and is flanked by the untranslated regions of LACV. The resulting chimeric virus retained the same robust growth kinetics in tissue culture as observed for either parent virus, and the virus remains highly infectious and immunogenic in mice. Although both LACV and JCV are highly neurovirulent in 21 day-old mice, with 50% lethal dose (LD₅₀) values of 0.1 and 0.5 log₁₀ PFU, respectively, chimeric JCV/LACV is highly attenuated and does not cause disease even after intracerebral inoculation of 10³ PFU. Parenteral vaccination of mice with 10¹ or 10³ PFU of JCV/LACV protected against lethal challenge with LACV, JCV, and Tahyna virus (TAHV). The chimeric virus was infectious and immunogenic in rhesus monkeys and induced neutralizing antibodies to JCV, LACV, and TAHV. When vaccinated monkeys were challenged with JCV, they were protected against the development of viremia. Generation of highly attenuated yet immunogenic chimeric bunyaviruses could be an efficient general method for development of vaccines effective against these pathogenic viruses.

Tubule-forming capacity of the movement proteins of alfalfa mosaic virus and brome mosaic virus

NARCIS (Netherlands)

Kasteel, D. T.; van der Wel, N. N.; Jansen, K. A.; Goldbach, R. W.; van Lent, J. W.

1997-01-01

The structural phenotype of the movement proteins (MPs) of two representatives of the Bromoviridae, alfalfa mosaic virus (AMV) and brome mosaic virus (BMV), was studied in protoplasts. Immunofluorescence microscopy showed that the MPs of these viruses, for which there has been no evidence of a

West Nile virus meningitis in a patient with human immunodeficiency virus type 1 infection

Directory of Open Access Journals (Sweden)

D. Pilalas

2017-09-01

Full Text Available The emergence of West Nile virus lineage 2 in central Macedonia, Greece, in 2010 resulted in large outbreaks for 5 consecutive years. We report a case of viral meningitis in an individual infected with human immunodeficiency virus type 1, which preceded the recognition of the outbreak and was confirmed retrospectively as West Nile virus neuroinvasive disease.

Detection of Pathogenic Viruses in Sewage Provided Early Warnings of Hepatitis A Virus and Norovirus Outbreaks

Science.gov (United States)

Hellmér, Maria; Paxéus, Nicklas; Magnius, Lars; Enache, Lucica; Arnholm, Birgitta; Johansson, Annette; Bergström, Tomas

2014-01-01

Most persons infected with enterically transmitted viruses shed large amounts of virus in feces for days or weeks, both before and after onset of symptoms. Therefore, viruses causing gastroenteritis may be detected in wastewater, even if only a few persons are infected. In this study, the presence of eight pathogenic viruses (norovirus, astrovirus, rotavirus, adenovirus, Aichi virus, parechovirus, hepatitis A virus [HAV], and hepatitis E virus) was investigated in sewage to explore whether their identification could be used as an early warning of outbreaks. Samples of the untreated sewage were collected in proportion to flow at Ryaverket, Gothenburg, Sweden. Daily samples collected during every second week between January and May 2013 were pooled and analyzed for detection of viruses by concentration through adsorption to milk proteins and PCR. The largest amount of noroviruses was detected in sewage 2 to 3 weeks before most patients were diagnosed with this infection in Gothenburg. The other viruses were detected at lower levels. HAV was detected between weeks 5 and 13, and partial sequencing of the structural VP1protein identified three different strains. Two strains were involved in an ongoing outbreak in Scandinavia and were also identified in samples from patients with acute hepatitis A in Gothenburg during spring of 2013. The third strain was unique and was not detected in any patient sample. The method used may thus be a tool to detect incipient outbreaks of these viruses and provide early warning before the causative pathogens have been recognized in health care. PMID:25172863

[Zika Virus and Zika Viral Disease].

Science.gov (United States)

Zhang, Shuo; Li, Dexin

2016-01-01

Since Zika virus (ZIKV) has firstly been isolated in 1947, Uganda, outbreaks of Zika fever have been reported in many areas such as in Africa, Southeast Asia and America. Imported cases in China also have been reported. Zika virus belongs to the family Flaviviridae, genus Flavivirus, and include Africa subtype and Asia subtype. It is a mosquito-borne virus primarily transmitted by Aedes aegypti mosquitoes. Sexual transmission, Blood transmission and mother-to-fetus transmission were also reported. Zika virus can go though blood-brain barrier and infect central nervous system. Symptoms are generally mild and self-limited, but recent evidence suggests a possible association between maternal Zika virus infection and adverse fetal outcomes, such as congenital microcephaly, as well as a possible association with Guillain-Barré syndrome. Laboratorial Diagnosis includes nucleic acid detection, Serological test, and isolation of virus. Currently, no vaccine or medication exists to prevent or treat Zika virus infection. Preventive measures against Zika virus infection should be taken through prevention of mosquito bites and surveillance in epidemic area.

Bovine virus diarrhea virus in free-living deer from Denmark.

Science.gov (United States)

Nielsen, S S; Roensholt, L; Bitsch, V

2000-07-01

Free-living deer are suggested as a possible source of infection of cattle with bovine virus diarrhea (BVD) virus. To examine this hypothesis blood samples from 476 free-living deer were collected during two different periods and tested for BVD virus and antibody in Denmark. In 1995-96, 207 animals were tested. These included 149 roe deer (Capreolus capreolus), 29 fallow deer (Dama dama), 20 red deer (Cervus elaphus) and one sika deer (Cervus sika). For the remaining eight animals no species information was available. In 1998-99, 269 animals were tested including 212 roe deer and 57 red deer. The animals were selected from areas with a relatively high prevalence of cattle herds with a BVD persistent infection status in 1997 and 1998. All 207 samples from 1995-96 were found antibody-negative except two samples from red deer. Only 158 of the 207 samples were tested for virus and were all found negative. Of the 269 samples from 1998-99 all but one were antibody negative. The positive sample was from a red deer. All samples were virus-negative. It appears that BVD infection does not occur in roe deer in Denmark. The presence of antibody in a few red deer from various districts in Jutland probably results from cattle to deer transmission, rather than spread among deer. Hence, the possibility of free-living deer as a source of infection for cattle in Denmark seems to be remote.

Control of Newcastle disease virus

Science.gov (United States)

Newcastle disease virus (NDV), also know as avian paramyxovirus serotype 1, is an important poultry pathogen worldwide. In naive poultry, the virulent forms of the virus cause high mortality. Because of this the virus is reportable to the World Organization for Animal Health and can be an important ...

Reduced incorporation of the influenza B virus BM2 protein in virus particles decreases infectivity

International Nuclear Information System (INIS)