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1.
J Med Microbiol ; 66(11): 1663-1672, 2017 Nov.
Article de Anglais | MEDLINE | ID: mdl-29068286

RÉSUMÉ

PURPOSE: There have been hardly any reports on the human immunodeficiency virus type 1 (HIV-1) drug-resistance profile from northern Ghana since antiretroviral therapy (ART) was introduced over a decade ago. This study investigated prevailing HIV-1 subtypes and examined the occurrence of drug resistance in ART-experienced patients in Tamale, the capital of the Northern Region of Ghana. METHODOLOGY: A cross-sectional study was carried out on HIV-infected adult patients receiving first-line ART. HIV viral load (VL) and CD4+ T-cell counts were measured. The pol gene sequences were analysed for genotypic resistance by an in-house HIV-1 drug-resistance test; the prevailing HIV-1 subtypes were analysed in detail.Results/Key findings. A total of 33 subjects were studied. Participants comprised 11 males (33.3 %) and 22 (66.7 %) females, with a median age of 34.5 years [interquartile range (IQR) 30.0-40.3]. The median duration on ART was 12 months (IQR 8.0-24). Of the 24 subjects successfully genotyped, 10 (41.7 %) viruses possessed at least one mutation conferring resistance to nucleoside or non-nucleoside reverse-transcriptase inhibitors (NRTIs/NNRTIs). Two-class drug resistance to NRTI and NNRTI was mostly detected (25 %, 6/24). The most frequent mutations were lamivudine-resistance M184V and efavirenz/nevirapine-resistance K103N. HIV-1 subtype CRF02_AG was predominant (79.2 %). Other HIV-1 subtypes detected were G (8.3 %), A3 (4.2 %) and importantly two (8.3 %) unique HIV-1 recombinant forms with CRF02_AG/A3 mosaic. CONCLUSION: HIV-1 shows high genetic diversity and on-going viral genetic recombination in the study region. Nearly 42 % of the patients studied harboured a drug-resistant virus. The study underscores the need for continued surveillance of HIV-1 subtype diversity; and of drug-resistance patterns to guide selection of second-line regimens in northern Ghana.


Sujet(s)
Agents antiVIH/pharmacologie , Résistance virale aux médicaments/génétique , Infections à VIH/épidémiologie , Infections à VIH/virologie , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/génétique , Adulte , Numération des lymphocytes CD4 , Études transversales , Femelle , Génotype , Ghana/épidémiologie , Humains , Mâle , Mutation , Phylogenèse , Prévalence , ARN viral , Charge virale
2.
PLoS Negl Trop Dis ; 7(9): e2435, 2013.
Article de Anglais | MEDLINE | ID: mdl-24069490

RÉSUMÉ

BACKGROUND: Viral hemorrhagic fevers (VHF) are acute diseases associated with bleeding, organ failure, and shock. VHF may hardly be distinguished clinically from other diseases in the African hospital, including viral hepatitis. This study was conducted to determine if VHF and viral hepatitis contribute to hospital morbidity in the Central and Northern parts of Ghana. METHODOLOGY/PRINCIPAL FINDINGS: From 2009 to 2011, blood samples of 258 patients with VHF symptoms were collected at 18 hospitals in Ashanti, Brong-Ahafo, Northern, Upper West, and Upper East regions. Patients were tested by PCR for Lassa, Rift Valley, Crimean-Congo, Ebola/Marburg, and yellow fever viruses; hepatitis A (HAV), B (HBV), C (HCV), and E (HEV) viruses; and by ELISA for serological hepatitis markers. None of the patients tested positive for VHF. However, 21 (8.1%) showed anti-HBc IgM plus HBV DNA and/or HBsAg; 37 (14%) showed HBsAg and HBV DNA without anti-HBc IgM; 26 (10%) showed anti-HAV IgM and/or HAV RNA; and 20 (7.8%) were HCV RNA-positive. None was positive for HEV RNA or anti-HEV IgM plus IgG. Viral genotypes were determined as HAV-IB, HBV-A and E, and HCV-1, 2, and 4. CONCLUSIONS/SIGNIFICANCE: VHFs do not cause significant hospital morbidity in the study area. However, the incidence of acute hepatitis A and B, and hepatitis B and C with active virus replication is high. These infections may mimic VHF and need to be considered if VHF is suspected. The data may help decision makers to allocate resources and focus surveillance systems on the diseases of relevance in Ghana.


Sujet(s)
Fièvres hémorragiques virales/épidémiologie , Fièvres hémorragiques virales/virologie , Hépatites virales humaines/épidémiologie , Hépatites virales humaines/virologie , Adolescent , Adulte , Anticorps antiviraux/sang , Sang/virologie , Enfant , Enfant d'âge préscolaire , ADN viral/sang , Surveillance épidémiologique , Femelle , Ghana/épidémiologie , Hôpitaux , Humains , Incidence , Mâle , Données de séquences moléculaires , ARN viral/sang , Analyse de séquence d'ADN , Virus/isolement et purification , Jeune adulte
3.
Pan Afr Med J ; 12: 74, 2012.
Article de Anglais | MEDLINE | ID: mdl-23077695

RÉSUMÉ

INTRODUCTION: Surveillance of acute flaccid surveillance (AFP) has been used world-wide to monitor the control and eradication of circulating wild polioviruses. The Polio Laboratory since its accreditation in 1996 has supported the Disease Surveillance Department for AFP surveillance. This study aims to isolate and characterize human enteroviruses from patients with AFP in Ghana. METHOD: Stool suspension was prepared from 308 samples received in 2009 from the surveillance activities throughout the country and inoculated on both RD and L20B cell lines. Isolates that showed growth on L20B were selected for real-time RT-PCR using degenerate and non-degenerate primers and probes. RD isolates were however characterized by microneutralisation technique with antisera pools from RIVM, The Netherlands and viruses that were untypable subjected to neutralization assay using antibodies specific for E71. RESULTS: Of the 308 samples processed, 17 (5.5%) grew on both L20B and RD cells while 32 (10.4%) grew on RD only. All 28 isolates from L20B were characterized by rRT-PCR as Sabin-like polioviruses. No wild poliovirus or VDPV was found. However from the microneutralisation assay, six different enteroviruses were characterized. Among these, Coxsackie B viruses were most predominant followed by Echovirus. Three children from whom non-polio enteroviruses were isolated had residual paralysis while one child with VAPP found. The non-polio enteroviruses circulated throughout the country with the majority (20.7%) from Ashanti region. CONCLUSION: This study showed the absence of wild or vaccine-derived poliovirus circulation in the country. However, the detection of three non-polio enteroviruses and one Sabin-like poliovirus with residual paralysis call for continuous surveillance even in the post polio eradication era.


Sujet(s)
Infections à entérovirus/épidémiologie , Enterovirus/isolement et purification , Paralysie/épidémiologie , Surveillance de la population/méthodes , Maladie aigüe , Adolescent , Animaux , Lignée cellulaire , Enfant , Infections à entérovirus/microbiologie , Fèces/microbiologie , Ghana/épidémiologie , Humains , Souris , Paralysie/virologie , Poliovirus/isolement et purification , RT-PCR
4.
BMC Res Notes ; 5: 478, 2012 Sep 03.
Article de Anglais | MEDLINE | ID: mdl-22937872

RÉSUMÉ

BACKGROUND: Viral infections during pregnancy can pose serious threats to mother and fetus from the time of conception to the time of delivery. These lead to congenital defects, spontaneous abortion and even death. The definitive diagnosis and management of pregnancy-related viral infections may be challenging especially in less resourced countries. CASE PRESENTATION: We present clinical and laboratory responses to the diagnosis and management of three cases of fulminant hepatitis secondary to Hepatitis E viral infection in pregnancy.Case 1 was a 31-year-old Ghanaian woman who presented with a week's history of passing dark urine as well as yellowish discoloration of the eyes. She subsequently developed fulminant hepatitis secondary to Hepatitis E viral infection, spontaneously aborted at 24 weeks of gestation and later died.Case 2 was also a 31-year-old Ghanaian woman who was admitted with a four-day history of jaundice. She had low grade fever, but no history of abdominal pain, haematuria, pale stool or pruritus. She next developed fulminant hepatitis secondary to Hepatitis E viral infection. However, she did not miscarry but died at 28 weeks of gestation.Case 3 was a 17-year-old Ghanaian woman who was referred to the tertiary health facility on account of jaundice and anaemia. She had delivered a live male infant at maturity of 32 weeks but noticed she was jaundiced and had a presentation of active disease 3 days prior to delivery. The baby was icteric at birth and on evaluation, had elevated bilirubin (mixed type) with normal liver enzymes. Hepatitis E virus infection was confirmed in both mother and baby. However, the jaundice and the hepatomegaly resolved in mother and baby after 5 and 12 days respectively. CONCLUSION: To the best of our knowledge, these are the first documented cases of fatal fulminant hepatic failures resulting from HEV infection in Ghana.


Sujet(s)
Hépatite E/complications , Complications infectieuses de la grossesse , Adolescent , Adulte , Issue fatale , Femelle , Ghana , Humains , Grossesse
5.
Microbiol Immunol ; 51(2): 235-42, 2007.
Article de Anglais | MEDLINE | ID: mdl-17310092

RÉSUMÉ

That HTLV-I infects CD4(+) T cells and enhances their cell growth has been shown as successful long-term in vitro proliferation in the presence of IL-2. It is known that T cells isolated from HAM patients possess strong ability for cell proliferation in vitro and mRNA of various cytokines are abundantly expressed in CNS tissues of HAM patients. Hence, the cytokine-induced proliferation could have an important role in pathogenesis and immune responses of HAM. In this study, we examined the relationship between cell proliferation and ability of in vitro cytokine production of CD4(+) T cell clones isolated from HAM patients. We started a culture from a single cell to isolate cell clones immediately after drawing blood from the patients using limiting dilution method, which could allow the cell to avoid in vitro HTLV-I infection after initiation of culture. Many cell clones were obtained and the rate of proliferation efficiency from a single cell was as high as 80%, especially in the 4 weeks' culture cells from HAM patients. These cells were classified as mainly Th0 phenotype that produce both IFN-gamma and IL-4 after CD3-stimulation. However, the frequency of proviral DNA in these cloned cells was significantly low. Our results indicate that the ability of cell proliferation in HAM patients is not restricted in HTLV-I-infected T cells. HTLV-Iuninfected CD4(+) T cells, mainly Th0 cells, also have a strong ability to respond to IL-2-stimulation, showing that unusual immune activation on T cells has been observed in HAM patients.


Sujet(s)
Lymphocytes T CD4+/immunologie , Lymphocytes T CD4+/virologie , Virus T-lymphotrope humain de type 1/immunologie , Paraparésie spastique tropicale/immunologie , Adulte , Sujet âgé , Lymphocytes T CD4+/cytologie , Clones cellulaires , Cytokines/génétique , Cytokines/immunologie , ADN viral/composition chimique , ADN viral/génétique , Femelle , Virus T-lymphotrope humain de type 1/génétique , Humains , Activation des lymphocytes , Mâle , Adulte d'âge moyen , Réaction de polymérisation en chaîne , Récepteurs aux antigènes des cellules T/immunologie
6.
Article de Anglais | MEDLINE | ID: mdl-16247965

RÉSUMÉ

RNA interference (RNAi) silences gene expression via short interfering 21-23 mer double-stranded RNA (siRNA) segments that guide cognate mRNA degradation in a sequence-specific manner. On the other hand, HIV-1 decoy TAR RNA are known to competitively interact with the HIV-1 Tat protein, to downregulate the enhanced gene expression from the long terminal repeat (LTR) promoters. Here we report that a novel expression construct, encoding both HIV-1 decoy TAR and Vif siRNA, as a single RNA substrate, was expressed under the control of the human U6 promoter, and later the TAR and siRNA were cleaved into their respective separate RNA by the endogenous RNase III-like enzyme. Each of the cleaved HIV-1 anti-genes then synergistically contributed toward enhancing the inhibition efficacy (>80%) of HIV-1 replication in transduced Jurkat cells. These results suggest that targeting HIV-1 mRNA with simultaneously expressed intracellular decoy TAR and Vif-siRNA could lead to an effective gene therapy strategy for the control and management of HIV-AIDS.


Sujet(s)
Agents antiVIH/pharmacologie , Régulation de l'expression des gènes viraux , Produits du gène vif/génétique , Techniques de transfert de gènes , Vecteurs génétiques , Répétition terminale longue du VIH/génétique , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/métabolisme , Lentivirus/génétique , Petit ARN interférent/métabolisme , Syndrome d'immunodéficience acquise/thérapie , Relation dose-effet des médicaments , Régulation négative , Thérapie génétique/méthodes , Humains , Cellules Jurkat , Modèles génétiques , Régions promotrices (génétique) , Interférence par ARN , ARN messager/métabolisme , Facteurs temps , Produits du gène vif du virus de l'immunodéficience humaine
7.
Nucleosides Nucleotides Nucleic Acids ; 24(10-12): 1745-61, 2005.
Article de Anglais | MEDLINE | ID: mdl-16438045

RÉSUMÉ

The human immunodeficiency virus type-1 (HIV-1)-encoded vif protein is essential for viral replication, virion production, and pathogenicity. HIV-1 Vif interacts with the endogenous human APOBEC3G protein (an mRNA editor) in target cells to prevent its encapsidation into virions. Some studies have established targets within the HIV-1 vif gene that are important for its biologic function; however, it is important to determine effective therapeutic targets in vif because of its critical role in HIV-1 infectivity and pathogenicity. The present study demonstrates that virions generated in transfected HeLa-CD4+ cells, especially from HIV-1 vif frame-shift mutant (3' delta vif; 5561-5849), were affected in splicing and had low infectivity in MT-4 cells. In addition, HIV-1 vif antisense RNA fragments constructed within the same region, notably the region spanning nucleic acid positions 5561-5705 (M-3'-AS), which corresponds to amino acid residues 96-144, significantly inhibited HIV-1 replication in MT-4 and reduced the HIV-1 vif mRNA transcripts and reporter gene (EGFP) expression. The generated virions showed low secondary infection in H9 cells. These data therefore suggest that the middle to the 3' end of vif is important for its biological activity in the target cells.


Sujet(s)
Produits du gène vif/génétique , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/génétique , ARN antisens/génétique , Réplication virale/génétique , Région 3' flanquante , Animaux , Cellules COS , Chlorocebus aethiops , Vecteurs génétiques , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/croissance et développement , Cellules HeLa , Humains , Produits du gène vif du virus de l'immunodéficience humaine
8.
Antivir Chem Chemother ; 15(2): 93-100, 2004 Mar.
Article de Anglais | MEDLINE | ID: mdl-15185727

RÉSUMÉ

A recent strategy in gene therapy has been using antiviral genes that are delivered to uninfected cells, either as RNA or DNA, to provide intracellular protection from human immunodeficiency virus type-1 (HIV-1) infection. Antisense oligonucleotides that are complementary to specific target genes suppress gene expression. A variety of techniques are available to enhance the cellular uptake and pharmacological effectiveness of antisense oligonucleotides, both in vitro and in vivo. We investigated the intracellular and tissue uptake of an oligonucleotide/cationic lipid complex, using a fluorescently labeled oligonucleotide. The antisense oligonucleotide was designed against the HIV-1 gag gene sequence. A T-cell line (MT-4) and PHA-stimulated peripheral blood mononuclear cells (PBMCs) were both infected with HIV-1(NL432) at an MOI of 0.01. One h later, both cultures were washed and treated with medium containing 1 microM antisense oligonucleotide. After a 3-day interval, the HIV-1 antigen expression was monitored by an indirect immunofluorescence assay. At 3 days post infection, we confirmed that p24 antigen production was inhibited by the antisense oligonucleotide/cationic lipid complex at a 1/10 ratio in the PBMCs, using enzyme-linked immunosorbent assay (ELISA). We also confirmed the intracellular existence of the complex by fluorescent microscopy. We investigated different means of transporting the antisense oligonucleotide/cationic lipid complex to mouse tissues by intravenous, intraperitoneal and subcutaneous injections. We observed that the anti-HIV-1 activity of the antisense oligonucleotide/cationic lipid complex was the result of enhanced cellular uptake, both in vitro and in vivo. Therefore, the antisense oligonucleotide/cationic lipid complex is an excellent system for the transport and delivery of genes to target cells, as it is effective both in vitro and in vivo.


Sujet(s)
Agents antiVIH/pharmacologie , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/effets des médicaments et des substances chimiques , Oligonucléotides antisens/pharmacologie , Réplication virale/effets des médicaments et des substances chimiques , Animaux , Agents antiVIH/pharmacocinétique , Transport biologique/physiologie , Lignée cellulaire , Relation dose-effet des médicaments , Vecteurs de médicaments , Évaluation préclinique de médicament , Femelle , Régulation de l'expression des gènes viraux/effets des médicaments et des substances chimiques , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/génétique , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/physiologie , Humains , Techniques in vitro , Agranulocytes/effets des médicaments et des substances chimiques , Liposomes , Souris , Souris de lignée BALB C , Oligonucléotides antisens/génétique , Oligonucléotides antisens/pharmacocinétique , Distribution tissulaire
9.
Biochem Biophys Res Commun ; 320(2): 544-50, 2004 Jul 23.
Article de Anglais | MEDLINE | ID: mdl-15219863

RÉSUMÉ

The human immunodeficiency virus type-1 (HIV-1)-encoded vif protein is essential for viral replication, virion production, and pathogenicity. HIV-1 vif interacts with the endogenous human APOBEC3G protein (an mRNA editor) in target cells to prevent its virions from encapsidation. Although some studies have established targets within the HIV-1 vif gene that are important for its biologic function, it is however important to further screen for effective therapeutic targets in the vif gene that could interfere with the HIV-1 vif-dependent infectivity and pathogenicity. This report demonstrates that HIV-1 vif antisense RNA fragments constructed within mid-3' region, notably the region spanning nucleic acid positions 5561-5705 (M-3'-AS), significantly inhibited HIV-1 replication in MT-4 and H9-infected cells and reduced the HIV-1 vif mRNA transcripts. These data clearly suggest that the above vif fragment, which corresponds to amino acid residues 96-144, could be an effective novel therapeutic target site for gene therapy applications, for the control and management of HIV-1 infection, due to its strong inhibition of HIV-1 replication in cells.


Sujet(s)
Gènes vif , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/génétique , ARN antisens/génétique , ARN messager/génétique , Lymphocytes T/virologie , Réplication virale/génétique , Séquence nucléotidique , Lignée cellulaire , Amorces ADN , Régulation négative , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/physiologie , Humains
10.
Nucleic Acids Res Suppl ; (2): 123-4, 2002.
Article de Anglais | MEDLINE | ID: mdl-12903136

RÉSUMÉ

The HIV-1 vif gene is a potential candidate in the quest for anti-retroviral interventions, due to its unique role in the target cell infection. We employed the antisense RNA strategy to determine the antiviral activity of intracellularly expressed anti-sense RNAs of various lengths complementary to the targeted HIV-1 vif gene. Expression vectors mediating the delivery of the vif-ORF, 5'-Vif, M-vif, and 3'-vif antisense RNAs under the CMV promoter were constructed using pcDNA 3.1. The COS cells transfected with the antisense vectors showed a steady-state of antisense RNA expression levels. In contrast, those co-transfected with the Infectious molecular clone, pNL-E, exhibited a significant reduction in the steady-state antisense RNA levels, which correlated with a significant reduction in p24 antigen production. Thus, this expression method for these antisense RNAs provides a promising gene therapy strategy for HIV-1.


Sujet(s)
Régulation négative/génétique , Produits du gène vif/génétique , Vecteurs génétiques , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/génétique , ARN antisens/génétique , Transfection , Animaux , Cellules COS , Cytomegalovirus/génétique , Cadres ouverts de lecture , Régions promotrices (génétique) , Produits du gène vif du virus de l'immunodéficience humaine
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