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[Ebola and Marburg hemorrhagic fever viruses: update on filoviruses].

The Ebola and Marburg viruses are the sole members of the Filoviridae family of viruses. They are characterized by a long filamentous form that is unique in the viral world. Filoviruses are among the most virulent pathogens currently known to infect humans. They cause fulminating disease characterized by acute fever followed by generalized hemorrhagic syndrome that is associated with 90% mortality in the most severe forms. Epidemic outbreaks of Marburg and Ebola viruses have taken a heavy toll on human life in Central Africa and devastated large ape populations in Gabon and Republic of Congo. …

A broad-spectrum antiviral targeting entry of enveloped viruses.

We describe an antiviral small molecule, LJ001, effective against numerous enveloped viruses including Influenza A, filoviruses, poxviruses, arenaviruses, bunyaviruses, paramyxoviruses, flaviviruses, and HIV-1. In sharp contrast, the compound had no effect on the infection of nonenveloped viruses. In vitro and in vivo assays showed no overt toxicity. LJ001 specifically intercalated into viral membranes, irreversibly inactivated virions while leaving functionally intact envelope proteins, and inhibited viral entry at a step after virus binding but before virus-cell fusion. LJ001 pretreatment al…

Nef proteins from simian immunodeficiency viruses are tetherin antagonists.

The tetherin/BST2/CD317 protein blocks the release of HIV-1 and other enveloped viruses by inducing tethering of nascent particles to infected cell surfaces. The HIV-1 Vpu protein antagonizes the antiviral activity of human but not monkey tetherins and many simian immunodeficiency viruses (SIVs) do not encode Vpu. Here, we show that the apparently "missing" antitetherin activity in SIVs has been acquired by several SIV Nef proteins. Specifically, SIV(MAC)/SIV(SMM), SIV(AGM), and SIV(BLU) Nef proteins can suppress tetherin activity. Notably, tetherin antagonism by SIV Nef proteins is species sp…

Reprogrammed viruses as cancer therapeutics: targeted, armed and shielded.

Virotherapy is currently undergoing a renaissance, based on our improved understanding of virus biology and genetics and our better knowledge of many different types of cancer. Viruses can be reprogrammed into oncolytic vectors by combining three types of modification: targeting, arming and shielding. Targeting introduces multiple layers of cancer specificity and improves safety and efficacy; arming occurs through the expression of prodrug convertases and cytokines; and coating with polymers and the sequential usage of different envelopes or capsids provides shielding from the host immune resp…

Widely conserved recombination patterns among single-stranded DNA viruses.

The combinatorial nature of genetic recombination can potentially provide organisms with immediate access to many more positions in sequence space than can be reached by mutation alone. Recombination features particularly prominently in the evolution of a diverse range of viruses. Despite rapid progress having been made in the characterization of discrete recombination events for many species, little is currently known about either gross patterns of recombination across related virus families or the underlying processes that determine genome-wide recombination breakpoint distributions observab…

Scientific barriers to developing vaccines against avian influenza viruses.

The increasing number of reports of direct transmission of avian influenza viruses to humans underscores the need for control strategies to prevent an influenza pandemic. Vaccination is the key strategy to prevent severe illness and death from pandemic influenza. Despite long-term experience with vaccines against human influenza viruses, researchers face several additional challenges in developing human vaccines against avian influenza viruses. In this Review, we discuss the features of avian influenza viruses, the gaps in our understanding of infections caused by these viruses in humans and o…

T-Cell epitope discovery for variola and vaccinia viruses.

Variola major, the causative agent of smallpox, afflicted mankind throughout history until the worldwide World Health Organisation WHO vacci … uch as variola virus. This review focuses on the efforts to identify CD8(+) T-Cell epitopes from poxviruses as a means to develop new vaccines and therapeutics. A wide variety of techniques have been employed by several research groups to provide complementary information regarding cellular immune responses to poxviruses. In the last several years well ov …

A simplified PCR methodology for semiquantitatively analyzing dengue viruses.

The standard methodology for titrating dengue viruses, the plaque assay, is slow, time consuming and relatively expensive. Other methods require machinery that may not be routinely accessible to all researchers, particularly those in developing nations. We therefore sought to develop a rapid, simplified semiquantitative polymerase chain reaction (PCR) methodology based on the use of a template mimic. In particular, it was desired that the mimic should be applicable for use a DNA template to avoid the requirement for producing an in vitro RNA transcript. A 511 base pair fragment of the capsid-P…

[Clinical examinations based on nucleic acids of hepatitis viruses].

Viral hepatitis is the most common cause of acute and chronic hepatitis. The term, viral hepatitis, generally refers to infections resulting from one of the hepatotrophic viruses: hepatitis A, B, C, D and E. As hepatitis B virus (HBV) and hepatitis C virus (HCV) mainly cause chronic hepatitis and hepatocellular carcinoma, early diagnosis, prevention and viral elimination are necessary. Eight genotypes of HBV have been detected by sequence divergence of >8% in the entire HBV genome, and designated by capital letters from A to H in the order of documentation. They have distinct geographical dist…

5'-Homoaristeromycin. Synthesis and antiviral activity against orthopox viruses.

An efficient synthesis of 5'-homoaristeromycin has been developed. This permitted an extensive antiviral analysis, which found potent activity toward vaccinia, cowpox, and monkeypox viruses. For comparative purposes, 5'-homoadenosine was made available by a newly designed route and found to be inactive.

Efficacy of zinc against common cold viruses: an overview.

OBJECTIVE: To review the laboratory and clinical evidence of the medicinal value of zinc for the treatment of the common cold. DATA SOURCES: Published articles identified through Medline (1980-2003) using the search terms zinc, rhinovirus, and other pertinent subject headings. Additional sources were identified from the bibliographies of the retrieved articles. STUDY SELECTION: By the author. DATA EXTRACTION: By the author. DATA SYNTHESIS: Human rhinoviruses, by attaching to the nasal epithelium via the intracellular adhesion molecule-1 (ICAM-1) receptor, cause most colds. Ionic zinc, base…

Reticuloendotheliosis viruses and derived vectors for human gene therapy.

The reticuloendotheliosis viruses (REV) spleen necrosis virus (SNV) and reticuloendotheliosis virus strain-A (REV-A) are amphotropic retroviruses which infect a large variety of cells of avian and some mammalian species. They normally do not infect primate or rodent cells. However, they efficiently infect and integrate their genome into that of human cells when they are pseudotyped with the envelope protein of other mammalian retroviruses or the G protein of vesicular stomatitis virus (VSV) or rabies viruses (RV). Moreover, SNV-derived retroviral vectors, which display single chain antibodies …

Вирусы герпеса, цитокины и гемосис в жизненном изнеможении.

ЦЕЛЬ: Заражение вирусом герпеса было связано с патогенезом атеросклероза. Мы проверили гипотезу о том, что жизненно важное истощение (VE) связано с множественными герпесвирусными инфекциями, такими, как герпес-синтекс, варицелла-зостерский вирус, вирус Эпштейн-Барр и цитомегаловир, а также с увеличением патогенного бремени (т.е. агрегированная серопозитивность к антителам иммуноглобулина G для герпеса-простых, вирус варицелла-зостера, вирус Эпштейна-Барра и цитомемегаловирус). Кроме того, мы изучили связь VE и патогенного бремени с показателями гемастаза и воспаления.Образцы крови были взяты у

Совпадение в аннотации оригинала
OBJECTIVE: Infections with herpes viruses have been implicated in the pathogenesis of atherosclerosis. We tested the hypothesis that vital exhaustion (VE) is associated with multiple herpesvirus infections, such as herpes simplex virus, varicella-zoster virus, Epstein-Barr virus, and cytomegalovirus, and with an increase in pathogen burden (ie, the aggregate…

Nylon membrane-immobilized PCR for detection of bovine viruses.

Bridge Technology is an amplification technique in which pairs of primers are immobilized on a solid support, allowing amplification only at … ection of the RNA-containing bovine viral diarrhea virus (BVDV) and two DNA-containing bovine herpesviruses 1 and 2 (BHV-1 and BHV-2). Nylon membranes with two spots of UV-immobilized primer pairs--one for BVDV and one for BHV--were used in amplification with both corresponding templates, with each template singly and with no template. When amplification …

[Herpes simplex viruses: biological characteristics, immunopathogenesis, diagnosis and treatment].

Herpes simplex virus (HSV) is the most common cause of sporadic encephalitis in developed countries. Herpes simplex virus type 1 (HSV-1) causes oropharyngeal infections, keratoconjunctivitis and infections of the central nervous system, while herpes simplex virus type 2 (HSV-2) in the immunocompetent most frequently causes genital infections. HSV-1 primary infection usually occurs in the early childhood but is also possible at adolescent age. HSV-2 primary infection is usually postponed till the adult age and coincides with the sexual activity. Common characteristics of these two viruses are a…

Selenium-dependent glutathione peroxidase modules encoded by RNA viruses.

Glutathione peroxidase (GPx) is the prototypical eukaryotic selenoprotein, with the rare amino acid selenocysteine (Sec) at the enzyme active site, encoded by the UGA codon in RNA. A DNA virus, Molluscum contagiosum, has now been shown to encode a functional selenium-dependent GPx enzyme. Using modifications of conventional sequence database searching techniques to locate potential viral GPx modules, combined with structurally guided comparative sequence analysis, we provide compelling evidence that Se-dependent GPx modules are encoded in a number of RNA viruses, including potentially serious …

Human T-cell leukemia viruses: epidemiology, biology, and pathogenesis.

The human T-cell lymphotropic viruses type I and type II are closely related human retroviruses that have similar biological properties, genetic organization and tropism for T lymphocytes. Along with the simian T-cell lymphoma virus type I, they define the group of retroviruses known as the primate T-cell leukemia/lymphoma viruses. Initially identified in 1980, the human T-cell lymphotropic virus type I has been implicated as the etiologic agent of adult T-cell leukemia/lymphoma and of a degenerative neurologic disorder known as tropical spastic paraparesis or human T-cell lymphotropic virus t…

Viruses and cancers: possible role of hepatitis C virus.

Oncogenesis is a multifactorial process in which environmental, genetic and infectious factors are variably involved. A possible role of specific viruses has been suggested in at least 15% of human cancers. Hepatitis C virus (HCV), which is both hepato- and lymphotropic, is responsible for various liver disorders, i.e. chronic hepatitis, cirrhosis and hepatocelluar carcinoma, as well as for a constellation of extrahepatic immune-mediated manifestations, among which is mixed cryoglobulinaemia. This is a systemic disorder secondary to a chronic, benign B-lymphocyte proliferation, which in some s…