RESUMO
Ebola hemorrhagic fever (EHF) epidemic currently ongoing in West Africa is not the first among numerous epidemics in the continent. Yet it seems to be the worst EHF epidemic outbreak caused by Ebola virus Zaire since 1976 as regards its extremely large scale and rapid spread in the population. Experiments to study the agent have continued for more than 20 years. The EHF virus has a relatively simple genome with seven genes and additional reading frame resulting from RNA editing. While being of a relatively low genetic capacity, the virus can be ranked as a standard for pathogenicity with the ability to evade the host immune response in uttermost perfection. The EHF virus has similarities with retroviruses, but belongs to (-)RNA viruses of a nonretroviral origin. Genetic elements of the virus, NIRV, were detected in animal and human genomes. EHF virus glycoprotein (GP) is a class I fusion protein and shows more similarities than distinctions in tertiary structure with SIV and HIV gp41 proteins and even influenza virus hemagglutinin. EHF is an unusual infectious disease, and studying the molecular basis of its pathogenesis may contribute to new findings in therapy of severe conditions leading to a fatal outcome.
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AIM: To evaluate the efficacy and safety of Arbidol (umifenovir) in adult patients with influenza. SUBJECTS AND METHODS: The analysis of the preliminary results of the multicenter double-blind randomized placebo-controlled post-marketing study ARBITR was performed. A total of 293 adults aged 18 to 65 years with influenza or acute respiratory tract infection of no more than 36 hours' duration were enrolled in the study. Individuals were randomized into 2 treatment groups: oral umifenovir 200 mg four times daily for 5 days or placebo four times daily for 5 days. The efficacy endpoints were time to resolution of all symptoms, severity of symptoms and illness, durations of virus shedding. RESULTS: The efficacy of umifenovir was evaluated in the group of 119 (40.6%) patients with influenza: 45 patients with laboratory-confirmed influenza and 74 patients whom diagnosis of influenza was made based on clinical and epidemiological data. Umifenovir had influence on the time to resolution of all symptoms. All symptoms were resolved within the first 60 hours after therapy initiation in 23.8% patients with laboratory-confirmed influenza in the umifenovir group and it was 5.7 times greater compared to placebo group (4.2%) (p < 0.05). Severity of illness, catarrhal symptoms and intoxication was reduced with umifenovir compared to placebo, reducing of severity was most evidently observed within the first 2-3 days following the therapy initiation. Umifenovir had a significant effect on viral shedding. The proportion of patients still shedding influenza virus on day 4 was significantly reduced in the umifenovir group compared to placebo (25 vs 53%, respectively; p < 0.05). CONCLUSION: It was found that the effect of umifenovir in the treatment of influenza in adults is most pronounced in the acute stage of the disease and appears in the reduction of time to resolution of all symptoms of the disease, reducing the severity of symptoms of the disease and durations of virus shedding.
Assuntos
Antivirais/uso terapêutico , Resfriado Comum/tratamento farmacológico , Indóis/uso terapêutico , Influenza Humana/tratamento farmacológico , Adolescente , Adulto , Idoso , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Resfriado Comum/virologia , Método Duplo-Cego , Feminino , Humanos , Indóis/administração & dosagem , Indóis/efeitos adversos , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Federação Russa , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto JovemRESUMO
The results of the clinical trial testing the efficacy of a new anti-influenza drug Triazavirin are presented in this work. The data of the trial were gathered during the 2010 influenza season. The treatment with oral Triazavirin significantly reduced the duration of the main clinical symptoms of influenza (intoxication, fever, respiratory symptoms), decreased the incidence of the influenza-related complications and the use of symptomatic drugs. The re-isolation rate of the influenza A and B viruses was significantly lower in the patients who were using Triazavirin. The analysis of the clinical data showed that the optimal prescribed dosage was 250 mg 3 times a day.
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Antivirais/administração & dosagem , Azóis/administração & dosagem , Influenza Humana , Triazinas/administração & dosagem , Adolescente , Adulto , Antivirais/efeitos adversos , Azóis/efeitos adversos , Feminino , Humanos , Vírus da Influenza A/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Triazinas/efeitos adversos , TriazóisRESUMO
The influence of antivirals, such as rimantadine, ribavirine and triazavirine on influenza virus replication in human cell cultures was evaluated. All the antivirals inhibited viral nucleoprotein NP synthesis. The strongest effect was shown for ribavirine in lung carcinoma A-549 cells and endothelial ECV-304 cells. Hoechst-33258 staining revealed induction of apoptosis in all the cell lines. Rimantadine and ribavirine inhibited virus-induced apoptosis while ribavirine enhanced it. The effect was registered in monolayer cell cultures as well as in suspension cell cultures. The influence of the antiviral drugs on the virus-induced cell proliferation in the suspension cell cultures is also described.
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Antivirais/farmacologia , Azóis/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Ribavirina/farmacologia , Rimantadina/farmacologia , Triazinas/farmacologia , Replicação Viral/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Técnicas de Cultura de Células , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/virologia , Humanos , Vírus da Influenza A/fisiologia , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Linfócitos/virologia , Suspensões , TriazóisRESUMO
In this review of literature modern notions on the role of birds in the evolution of the pathogenicity signs and immune system of the main and intermediate hosts of influenza viruses, as well as on the mechanisms of overcoming interspecific barriers, are analyzed. The chronology of the spread of "avian" influenza among humans, starting from 1997, the properties of the natural reservoir of this infection, and in particular influenza viruses A, the ways of their variability and evolution are presented. The conclusion has been made that the mixing, joint evolution, recombination and reassortment of viral genomes may be caused by global events in individual geographical regions.
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Surtos de Doenças , Genoma Viral , Vírus da Influenza A/genética , Influenza Aviária/epidemiologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Animais , Ásia , Aves , Reservatórios de Doenças , Europa (Continente) , Evolução Molecular , Variação Genética , Humanos , Vírus da Influenza A/patogenicidade , Influenza Aviária/virologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Recombinação Genética , Estados UnidosRESUMO
Ebola hemorrhagic fever (EHF) epidemic currently ongoing in West Africa is not the first among numerous epidemics in the continent. Yet it seems to be the worst EHF epidemic outbreak caused by Ebola virus Zaire since 1976 as regards its extremely large scale and rapid spread in the population. Experiments to study the agent have continued for more than 20 years. The EHF virus has a relatively simple genome with seven genes and additional reading frame resulting from RNA editing. While being of a relatively low genetic capacity, the virus can be ranked as a standard for pathogenicity with the ability to evade the host immune response in uttermost perfection. The EHF virus has similarities with retroviruses, but belongs to (-)RNA viruses of a nonretroviral origin. Genetic elements of the virus, NIRV, were detected in animal and human genomes. EHF virus glycoprotein (GP) is a class I fusion protein and shows more similarities than distinctions in tertiary structure with SIV and HIV gp41 proteins and even influenza virus hemagglutinin. EHF is an unusual infectious disease, and studying the molecular basis of its pathogenesis may contribute to new findings in therapy of severe conditions leading to a fatal outcome.
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The paper contains an analysis of research on designing drugs based on acridine derivatives. The discussed series of compounds is of essential value since acridines belong to the group of natural compounds with the pronounced antibacterial and anti-tumor activity. Improved chemical-synthesis techniques made it possible to synthesize both simple and complex compounds of the acridine series; they displayed a clear pharmacological activity as anti-proliferative, anti-tumor and antiparasitic preparations. The ability to induce interferons (INF), type 1, is an expected property of simple acridine derivatives. A variety of INF inducers, now used clinically, have been designed recently on the basis of the above compounds. The most well-known acridine derivatives, their pharmacological properties, action mechanisms and outlooks for practical application are described in the paper. The unique qualities of acridines are primarily attractive due to the possibility of using them for the purpose-oriented designing of drugs. Thus, acridines were used as a basis to create the specific regulatory HIV-1 elements, proliferation inhibitors of leukemia cells and new anti-tumor drugs. The elaboration of complexes of acridines derivatives combined with peptides intercalating specifically into the DNA big or small grooves is the most outstanding trend of acridines' research--it opens up prospects for using them in the synthesis of compounds regulating the gene expression.
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Acridinas/química , Acridinas/farmacologia , Acridinas/síntese química , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Técnicas de Química Combinatória , Desenho de Fármacos , Resistência a Múltiplos Medicamentos , Humanos , Relação Estrutura-AtividadeRESUMO
The etiological structure of influenza-like was analyzed in the population in cities and towns and in Russia as a whole in November 1998 to April 1999 by the findings of immunofluorescence and serological surveys of patients with acute respiratory viral infections (ARVI). By the results of both tests, the proportion of the incidence of influenza A (H3N2) was largest, the decreasing order in their significance was as follows: adenoviruses, type 3 parainfluenza virus, RSV, influenza B virus, influenza A(H1N1), types 2 and 1 parainfluenza virus. All influenza viruses A(H1N1) were isolated in Samara in February 1999. Three of them were similar to the reference strain A/Johannesburg/82/96 in antigenic properties, two strains appeared to be its drift variants. No A/Beijing/262/95 (H1N1)-like viruses recommended for incorporation as part of vaccines were detected. All influenza A(H3N2) viruses were drift variants of strain A/Sydney/05/97, and all influenza B viruses were similar to the reference strain B/Harbin/07/94 in antigenic structure.
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Surtos de Doenças , Influenza Humana/virologia , Infecções Respiratórias/virologia , Técnicas de Laboratório Clínico , Imunofluorescência , Humanos , Influenza Humana/epidemiologia , Infecções Respiratórias/epidemiologia , Federação Russa/epidemiologiaRESUMO
The antigenic properties of 51 strains of influenza virus A(H1N1), isolated in different cities of Russia during the epidemic of 1998, were studied. Most of these strains (49) proved to be similar to virus A/Bern/07/95 in the antigenic structure of hemagglutinin, but 2 strains isolated in Ulan-Ude were found to be closely related to new antigenic variants of this virus: A/Beijing/262/95 and A/Fukuoka/c7/98. The analysis of the antigenic structure of influenza-like diseases (ILD) in different cities of Russia revealed that adenoviruses causing up to 10.9-14.6% of all acute respiratory virus infections dominated at the pre- and post-epidemic periods. RS-viruses, parainfluenza viruses of types 2 and 3 circulated during the whole season (their proportion was 5.1-6.6%). The intensity of the circulation of influenza viruses A(H1N1) and A(H3N2) increased, starting from January, and continued till April 1998; its peak was observed in February-March in most of the cities of Russia (up to 37.5-41.6% according to the results of immunofluorescent diagnostics and 53-73% of ILD according to the results of the hemagglutination inhibition test). The occurrence of influenza B during this season was very low.