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1.
Viruses ; 15(8)2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37631963

RESUMEN

The Zika virus (ZIKV) is a widespread mosquito-borne pathogen. Phylogenetically, two lineages of ZIKV are distinguished: African and Asian-American. The latter became the cause of the 2015-2016 pandemic, with severe consequences for newborns. In West African countries, the African lineage was found, but there is evidence of the emergence of the Asian-American lineage in Cape Verde and Angola. This highlights the need to not only monitor ZIKV but also sequence the isolates. In this article, we present a case report of Zika fever in a pregnant woman from Guinea identified in 2018. Viral RNA was detected through qRT-PCR in a serum sample. In addition, the seroconversion of anti-Zika IgM and IgG antibodies was detected in repeated blood samples. Subsequently, the virus was isolated from the C6/36 cell line. The detected ZIKV belonged to the African lineage, the Nigerian sublineage. The strains with the closest sequences were isolated from mosquitoes in Senegal in 2011 and 2015. In addition, we conducted the serological screening of 116 blood samples collected from patients presenting to the hospital of Faranah with fevers during the period 2018-2021. As a result, it was found that IgM-positive patients were identified each year and that the seroprevalence varied between 5.6% and 17.1%.


Asunto(s)
Culicidae , Infección por el Virus Zika , Virus Zika , Recién Nacido , Animales , Femenino , Embarazo , Humanos , Infección por el Virus Zika/diagnóstico , Infección por el Virus Zika/epidemiología , Virus Zika/genética , Guinea/epidemiología , Estudios Seroepidemiológicos , Inmunoglobulina M
2.
Viruses ; 15(1)2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-36680245

RESUMEN

BACKGROUND: Since most of the modern human population has no anti-smallpox immunity, it is extremely important to develop and implement effective drugs for the treatment of smallpox and other orthopoxvirus infections. The objective of this study is to determine the main characteristics of the chemical substance NIOCH-14 and its safety and bioavailability in the body of laboratory animals. METHODS: The safety of NIOCH-14 upon single- or multiple-dose intragastric administration was assessed according to its effect on the main hematological and pathomorphological parameters of laboratory mice and rats. In order to evaluate the pharmacokinetic parameters of NIOCH-14 administered orally, a concentration of ST-246, the active metabolite of NIOCH-14, in mouse blood and organs was determined by tandem mass spectrometry and liquid chromatography. RESULTS: The intragastric administration of NIOCH-14 at a dose of 5 g/kg body weight caused neither death nor signs of intoxication in mice. The intragastric administration of NIOCH-14 to mice and rats at doses of 50 and 150 µg/g body weight either as a single dose or once daily during 30 days did not cause animal death or critical changes in hematological parameters and the microstructure of internal organs. The tissue availability of NIOCH-14 administered orally to the mice at a dose of 50 µg/g body weight, which was calculated according to concentrations of its active metabolite ST-246 for the lungs, liver, kidney, brain, and spleen, was 100, 69.6, 63.3, 26.8 and 20.3%, respectively. The absolute bioavailability of the NIOCH-14 administered orally to mice at a dose of 50 µg/g body weight was 22.8%. CONCLUSION: Along with the previously determined efficacy against orthopoxviruses, including the smallpox virus, the substance NIOCH-14 was shown to be safe and bioavailable in laboratory animal experiments.


Asunto(s)
Viruela , Virus de la Viruela , Humanos , Ratas , Ratones , Animales , Preparaciones Farmacéuticas , Administración Oral , Animales de Laboratorio
3.
Biomed Res Int ; 2021: 6662027, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34258278

RESUMEN

PURPOSE: The aim of this work was to analyze the complete genome of probiotic bacteria Lactobacillus plantarum 8 RA 3, Lactobacillus fermentum 90 TC-4, Lactobacillus fermentum 39, Bifidobacterium bifidum 791, Bifidobacterium bifidum 1, and Bifidobacterium longum 379 and to test their activity against influenza A and SARS-CoV-2 viruses. METHODS: To confirm the taxonomic affiliation of the bacterial strains, MALDI TOF mass spectrometry and biochemical test systems were used. Whole genome sequencing was performed on the Illumina Inc. MiSeq platform. To determine the antiviral activity, A/Lipetsk/1V/2018 (H1N1 pdm09) (EPI_ISL_332798) and A/common gull/Saratov/1676/2018 (H5N6) (EPI_ISL_336925) influenza viruses and SARS-CoV-2 virus strain Australia/VIC01/2020 (GenBank: MT007544.1) were used. RESULTS: All studied probiotic bacteria are nonpathogenic for humans and do not contain the determinants of transmission-type antibiotic resistance and integrated plasmids. Resistance to antibiotics of different classes is explained by the presence of molecular efflux pumps of the MatE and MFS families. Cultures of L. fermentum 90 TC 4, L. plantarum 8 RA 3, and B. bifidum 791 showed a pronounced activity against influenza A viruses in MDCK cells. Activity against the SARS-CoV-2 virus was demonstrated only by the L. fermentum 90 TC 4 strain in VERO cells. CONCLUSIONS: The studied probiotic bacteria are safe, have antiviral activity, and are of great importance for the prevention of diseases caused by respiratory viruses that can also infect the human intestine.


Asunto(s)
Bifidobacterium longum/genética , COVID-19/metabolismo , Lactobacillus/genética , Probióticos/farmacología , SARS-CoV-2/metabolismo , Animales , COVID-19/terapia , Chlorocebus aethiops , Perros , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Subtipo H1N1 del Virus de la Influenza A , Gripe Humana , Células de Riñón Canino Madin Darby , Células Vero
5.
Antivir Ther ; 22(4): 345-351, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27924780

RESUMEN

BACKGROUND: The influenza A virus accounts for serious annual viral upper respiratory tract infections. It is constantly able to modify its antigenic structure, thus evading host defence mechanisms. Moreover, currently available anti-influenza agents have a rather limited application, emphasizing the further need for new effective treatments. One of them is ergoferon, a drug containing combined polyclonal antibodies - anti-interferon gamma, anti-CD4 receptor and anti-histamine - in released-active form. The purpose of the study was to assess ergoferon antiviral efficacy in mice challenged with the A/Aichi/2/68 (H3N2) influenza virus. METHODS: The virus was inoculated intranasally at a 90% lethal dose. Ergoferon was administered at 0.4 ml/day per os in a preventive and therapeutic regimen - daily for 5 days prior to and for 16 days after the challenge. The reference product, Tamiflu (oseltamivir), was used as a positive control treatment - at 20 mg/kg/day for 5 days after the challenge. Mice in the negative control group received distilled water which had been utilized for test sample preparation; untreated control animals received no treatment. Antiviral efficacy was assessed by an increase in survival rate, average life expectancy and virus titre reduction in the challenged mouse lungs. RESULTS: Survival rate and average life expectancy values were increased significantly in groups treated with ergoferon and Tamiflu, as compared with controls. Lung virus titres were reduced in these groups as observed on days 2 and 4 post-inoculation. CONCLUSIONS: Ergoferon demonstrated antiviral activity by reducing the severity and duration of the major signs of induced influenza infection.


Asunto(s)
Anticuerpos/farmacología , Antivirales/farmacología , Factores Inmunológicos/farmacología , Subtipo H3N2 del Virus de la Influenza A/efectos de los fármacos , Infecciones por Orthomyxoviridae/tratamiento farmacológico , Animales , Antígenos CD4/antagonistas & inhibidores , Antígenos CD4/inmunología , Esquema de Medicación , Cálculo de Dosificación de Drogas , Femenino , Histamina/inmunología , Subtipo H3N2 del Virus de la Influenza A/crecimiento & desarrollo , Subtipo H3N2 del Virus de la Influenza A/inmunología , Interferón gamma/antagonistas & inhibidores , Interferón gamma/inmunología , Longevidad/inmunología , Pulmón/efectos de los fármacos , Pulmón/inmunología , Pulmón/virología , Ratones , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/mortalidad , Infecciones por Orthomyxoviridae/virología , Oseltamivir/farmacología , Análisis de Supervivencia , Resultado del Tratamiento , Carga Viral/efectos de los fármacos
6.
J Gen Virol ; 97(5): 1229-1239, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26861777

RESUMEN

Antiviral activity of the new chemically synthesized compound NIOCH-14 (a derivative of tricyclodicarboxylic acid) in comparison with ST-246 (the condensed derivative of pyrroledione) was observed in experiments in vitro and in vivo using orthopoxviruses including highly pathogenic ones. After oral administration of NIOCH-14 to outbred ICR mice infected intranasally with 100 % lethal dose of ectromelia virus, it was shown that 50 % effective doses of NIOCH-14 and ST-246 did not significantly differ. The 'therapeutic window' varied from 1 day before infection to 6 days post-infection (p.i.) to achieve 100-60 % survival rate. The administration of NIOCH-14 and ST-246 to mice resulted in a significant reduction of ectromelia virus titres in organs examined as compared with the control and also reduced pathological changes in the lungs 6 days p.i. Oral administration of NIOCH-14 and ST-246 to ICR mice and marmots challenged with monkeypox virus as compared with the control resulted in a significant reduction of virus production in the lungs and the proportion of infected mice 7 days p.i. as well as the absence of disease in marmots. Significantly lower proportions of infected mice and virus production levels in the lungs as compared with the control were demonstrated in experiments after oral administration of NIOCH-14 and ST-246 to ICR mice and immunodeficient SCID mice challenged with variola virus 3 and 4 days p.i., respectively. The results obtained suggest good prospects for further study of the chemical compound NIOCH-14 to create a new smallpox drug on its basis.


Asunto(s)
Antivirales/química , Antivirales/farmacología , Ácidos Dicarboxílicos/química , Ácidos Dicarboxílicos/farmacología , Mpox/tratamiento farmacológico , Viruela/tratamiento farmacológico , Animales , Benzamidas/síntesis química , Benzamidas/farmacología , Chlorocebus aethiops , Femenino , Isoindoles/síntesis química , Isoindoles/farmacología , Masculino , Marmota , Ratones , Ratones Endogámicos ICR , Ratones SCID , Estructura Molecular , Monkeypox virus , Virus de la Viruela , Células Vero
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