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1.
Transbound Emerg Dis ; 64(5): 1393-1404, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27211823

RESUMEN

African swine fever (ASF) is an important emerging transboundary animal disease (TAD), which currently has an impact on many countries in Africa, Eastern Europe, the Caucasus and the Russian Federation. The current situation in Europe shows the ability of the virus to rapidly spread, which stands to threaten the global swine industry. At present, there is no viable vaccine to minimize spread of the disease and stamping out is the main source of control. In February 2011, Ethiopia had reported its first suspected outbreaks of ASF. Genomic analyses of the collected ASF virus (ASFV) strains were undertaken using 23 tissue samples collected from domestic swine in Ethiopia from 2011 to 2014. The analysis of Ethiopian ASFVs partial p72 gene sequence showed the identification of a new genotype, genotype XXIII, that shares a common ancestor with genotypes IX and X, which comprise isolates circulating in Eastern African countries and the Republic of Congo. Analysis of the p54 gene also followed the p72 pattern and the deduced amino acid sequence of the central variable region (CVR) of the B602L gene showed novel tetramer repeats not previously characterized.


Asunto(s)
Virus de la Fiebre Porcina Africana/genética , Fiebre Porcina Africana/virología , Variación Genética , Fiebre Porcina Africana/diagnóstico , Fiebre Porcina Africana/epidemiología , Virus de la Fiebre Porcina Africana/clasificación , Virus de la Fiebre Porcina Africana/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Brotes de Enfermedades/veterinaria , Etiopía/epidemiología , Genotipo , Filogenia , Análisis de Secuencia de ADN/veterinaria , Porcinos
2.
Transbound Emerg Dis ; 64(5): 1598-1609, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27480888

RESUMEN

Sequencing and analysis of three discrete genome regions of African swine fever viruses (ASFV) from archival samples collected in 2007-2011 and active and passive surveillance between 2012 and 2015 in Nigeria were carried out. Analysis was conducted by genotyping of three single-copy African swine fever (ASF) genes. The E183L and B646L genes that encode structural proteins p54 and p72, respectively, were utilized to delineate genotypes before intragenotypic resolution by characterization of the tetrameric amino acid repeat region within the hypervariable central variable region of the B602L gene. The results showed no variation in the p72 and p54 gene regions sequenced. Phylogeny of p72 sequences revealed that all the Nigerian isolates belonged to genotype I, while that of the p54 recovered the Ia genotype. Analysis of B602L gene revealed the differences in the number of tetrameric repeats. Four new variants (Tet-15, Tet-17a, Tet-17b and Tet-48) were recovered, while a fifth variant (Tet-20) was the most widely distributed in the country displacing Tet-36 reported previously in 2003-2006. The viruses responsible for ASF outbreaks in Nigeria are from very closely related but mutated variants of the virus that have been circulating since 1997. A practical implication of the genetic variability of the Nigerian viral isolates in this study is the need for continuous sampling and analysis of circulating viruses, which will provide epidemiological information on the evolution of ASFV in the field versus new incursion for informed strategic control of the disease in the country.


Asunto(s)
Virus de la Fiebre Porcina Africana/genética , Fiebre Porcina Africana/epidemiología , Fiebre Porcina Africana/virología , Virus de la Fiebre Porcina Africana/aislamiento & purificación , Animales , Secuencia de Bases , Brotes de Enfermedades , Regulación Viral de la Expresión Génica , Variación Genética , Genotipo , Nigeria/epidemiología , Filogenia , Análisis de Secuencia de ADN , Porcinos , Proteínas Estructurales Virales/genética , Proteínas Estructurales Virales/metabolismo
3.
Rev Sci Tech ; 33(3): 893-901, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25812213

RESUMEN

The seroprevalence of Rift Valley fever was determined in cattle, sheep and goats in selected areas of northern and central Burkina Faso. A total of 520 serum samples were screened for anti-Rift Valley fever virus immunoglobulin G (IgG) antibodies using an inhibition enzyme-linked immunosorbent assay (ELISA). An average seroprevalence of 7.67% (range 5% to 20%) was found in ruminants in Seno and Soum provinces, and prevalences of 20% and 22.5% in cattle in Yatenga and Oubritenga provinces, respectively. The location, species and age of the animals were found to influence the seroprevalence. All the ELISA IgG-positive samples were tested for IgM in a competitive ELISA and were found negative, thus ruling out recent infections. The IgG-positive samples, including weak positives, were further tested in a serum neutralisation test for neutralising antibodies and 54.5% of these samples tested positive. The results show that the virus is in circulation in central and northern regions of Burkina Faso, suggesting the need for improved surveillance and control systems to prevent future outbreaks and the consequent economic impact of the disease in Burkina Faso livestock.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Enfermedades de las Cabras/epidemiología , Fiebre del Valle del Rift/epidemiología , Enfermedades de las Ovejas/epidemiología , Envejecimiento , Animales , Anticuerpos Antivirales/sangre , Burkina Faso/epidemiología , Bovinos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Cabras , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Pruebas Serológicas , Ovinos
4.
Nat Prod Res ; 26(11): 1069-74, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21978195

RESUMEN

An aqueous acetone extract of the stem with the leaves of Bauhinia rufescens and its fractions were analysed for their antioxidant and enzyme-inhibitory activities, as well as their phytochemical composition. For measurement of the antioxidant activities, the 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azinobis(3-ethylbenzoline-6-sulphonate) and the ferric-reducing methods were used. The results indicated that the aqueous acetone, its ethyl acetate and n-butanol fractions possessed considerable antioxidant activity. Further, the xanthine oxidase and lipoxygenase inhibitory assays showed that the n-butanol fraction possessed compounds that can inhibit both these enzymes. In the phytochemical analysis, the ethyl acetate and the n-butanol fractions of the aqueous acetone extract were screened by HPLC-MS for their phenolic content. The results indicated the presence of hyperoside, isoquercitrin, rutin quercetin, quercitrin, p-coumaric and ferulic acids in the non-hydrolysed fractions. In the hydrolysed fractions, kaempferol, p-coumaric and ferulic acids were identified.


Asunto(s)
Antioxidantes/farmacología , Bauhinia/química , Inhibidores Enzimáticos/farmacología , Inhibidores de la Lipooxigenasa/farmacología , Fenoles/farmacología , Xantina Oxidasa/antagonistas & inhibidores , Cromatografía Líquida de Alta Presión , Espectrometría de Masas
5.
Nat Prod Res ; 25(19): 1777-88, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21656419

RESUMEN

Stereospermum kunthianum was used for biological and phytochemical investigations. In biological studies, antioxidant activities were investigated with water, methanol and aqueous acetone extracts. Furthermore, the xanthine oxidase inhibitory activity and the diuretic activity of an aqueous acetone extract were evaluated. In the phytochemical investigations, the flavonoids and polyphenols were quantified spectrophotometrically in all extracts followed by high-performance liquid chromatography-mass spectrometry (HPLC-MS) analysis of an aqueous acetone extract. The 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing/antioxidant power (FRAP) and 2,2'-azinobis (3-ethylbenzoline-6-sulphonate (ABTS) methods have shown that the aqueous acetone extract presents the best antioxidant activities. This aqueous acetone extract was further proven to have interesting xanthine oxidase inhibitory activity, but only a weak diuretic activity. This aqueous acetone extract also possessed the highest phenolic and flavonoid contents. HPLC-MS analysis allowed identifying and quantifying, rutin, isoquercitrin, quercetin, hyperoside, quercitrin and luteolin and the glycosides of ferulic, sinapic p-coumaric acids and kaempferol, apigenin in aqueous-acetone extract.


Asunto(s)
Antioxidantes/farmacología , Bignoniaceae/química , Diuréticos/farmacología , Extractos Vegetales/farmacología , Acetona , Animales , Antioxidantes/química , Compuestos de Bifenilo/antagonistas & inhibidores , Cromatografía Líquida de Alta Presión , Diuréticos/química , Flavonoides/análisis , Concentración 50 Inhibidora , Masculino , Espectrometría de Masas , Metanol , Picratos/antagonistas & inhibidores , Extractos Vegetales/química , Polifenoles/análisis , Potasio/orina , Ratas , Ratas Wistar , Sodio/orina , Espectrofotometría , Ácido Úrico/orina , Agua , Xantina Oxidasa/metabolismo
6.
Nat Prod Res ; 25(2): 93-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21246435

RESUMEN

Balanites aegyptiaca is a tropical plant which is widely used for medicinal purposes in several African countries, including Burkina Faso. Despite its widespread use, little is known about its phenolic content. This study sought to carry out a screening of the polyphenols from the leaves and galls of B. aegyptiaca. A high-performance liquid chromatography-mass spectrometry method was used to investigate the phenolic content in the parts of the plant studied here. The phenolic acid profile showed the presence of gentisic, p-coumaric, caffeic, ferulic and sinapic acids in the crude and hydrolysed extracts. The flavonoids pattern showed hyperoside, isoquercitrin, rutoside and quercitrin in the crude extract of leaves. Myricetol, quercetol and kaempferol were found after acid hydrolysis of the leaves extract. Ferulic acid, isoquercitrin, rutoside and quercitrin were identified as major phenolic compounds in this study.


Asunto(s)
Balanites/química , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos , Fenoles/análisis , Hojas de la Planta/química
7.
Pak J Biol Sci ; 13(8): 362-8, 2010 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-20836295

RESUMEN

The present study aimed to test the validity of Balanites aegyptiaca remedies used for the treatment of rheumatisms and mental disorders by examining the antioxidant, xanthine oxidase and acetylcholinesterase inhibitory activities of galls and leaves extracts and fractions. The total phenolics and flavonoids were measured using Folin-Ciocalteu and AlCl3 reagents, respectively. Two methods i.e., FRAP and ABTS were used to estimate the total antioxidant capacity of the plant materials. The FRAP and ABTS antioxidant activities showed that among all extracts and fractions tested, the best antioxidant activities were found with the galls dichloromethane and the leaves ethyl acetate fractions. The antioxidant activities did correlated significantly with the total phenolic and flavonoid contents. The study also showed that B. aegyptiaca galls and leaves fractions exhibited a moderate xanthine oxidase inhibitory activity comparatively to the acetylcholinesterase which was weakly inhibited by the tested extracts and fractions.


Asunto(s)
Acetilcolina/metabolismo , Antioxidantes/metabolismo , Balanites , Inhibidores de la Colinesterasa/metabolismo , Extractos Vegetales/metabolismo , Xantina Oxidasa , Animales , Balanites/química , Balanites/metabolismo , Flavonoides/aislamiento & purificación , Flavonoides/metabolismo , Humanos , Fenoles/aislamiento & purificación , Fenoles/metabolismo , Extractos Vegetales/uso terapéutico , Reproducibilidad de los Resultados , Xantina Oxidasa/antagonistas & inhibidores , Xantina Oxidasa/metabolismo
8.
Pak J Biol Sci ; 12(3): 264-9, 2009 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19579956

RESUMEN

In this study, the antioxidant and antibacterial activities of acetone extract, ethyl acetate, n-butanol and n-hexane fractions of acetone extract from leaves of Combretum nioroense Aubrév. ex Keay were investigated. The total phenolics and total flavonoids contents in the fractions and acetone extract were determined by spectrophotometric methods using Folin-Ciocalteu and AlCl3, respectively. Two methods were adopted to assess the antioxidant activities: the Ferric Reducing Antioxidant Power (FRAP) and the radical scavenging activity of 2, 2'-azinobis (3-ethylbenzothiozoline-6-sulfonate) radical cation (ABTS). The Minimum Inhibitory Concentrations (MICs) of the extract and fractions against pathogenic bacteria (4) and serotyped bacteria (4) from American Type Culture Collection (ATCC) were also determined using the agar-well diffusion method. The results showed that the butanol fraction, with the highest phenolic content, exhibited the best antioxidant and antibacterial activities as compared to the ethyl acetate fraction which contains more flavonoids.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Bacterias/efectos de los fármacos , Combretum/química , Combretum/anatomía & histología , Flavonoides/química , Depuradores de Radicales Libres/farmacología , Pruebas de Sensibilidad Microbiana , Fenoles/química , Hojas de la Planta/química
9.
Pak J Biol Sci ; 11(11): 1429-35, 2008 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-18817242

RESUMEN

Aqueous acetone extracts prepared from five Indigofera species of Burkina Faso, namely Indigofera colutea (Burm.) Murril., I. macrocalyx Guilld et Perr., I. nigritana Hook f., I. pulchra willd. and I. tinctoria L., were investigated for their phytochemical composition and their antioxidant activities. Standard methods and TLC were used to screen the phytochemical composition. The total phenolic and flavonoid content of extracts were assessed by Folin-Ciocalteu and AlCl3 methods, respectively. These extracts were also evaluated for their antioxidant potentials using ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonate) (ABTS) assays. Flavonoids, saponins, quinones, sterols/triterpenes and tannins were present in all these species except for I. pulchra where quinones were not found. Gallic acid, caffeic acid, rutin and myricetin in I. colutea; gallic acid, quercitrin, myricetin in I. tinctoria; galangin and myricetin in I. macrocalyx were identified by thin layer chromatography. Among these, I. colutea, I. tinctoria, I. nigritana and I. macrocalyx, which had the highest phenolic content, were also found to possess the best antioxidant activities. The results indicated a good correlation between antioxidant activities and total phenolic content (p<0.05 for FRAP/DPPH and DPPH/ABTS and p<0.01 for FRAP/ABTS). These plants represent promising sources of natural antioxidants and these findings give scientific bases to their ethnopharmacological uses.


Asunto(s)
Antioxidantes/análisis , Flavonoides/análisis , Indigofera/química , Fenoles/análisis , Burkina Faso , Indigofera/clasificación , Polifenoles , Especificidad de la Especie
10.
Avian Pathol ; 34(2): 127-32, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16191693

RESUMEN

Several field isolates of fowlpoxvirus (FPV) from Burkina Faso, West Africa, were isolated and partly evaluated by molecular analysis. In addition, the in ovo antiviral activity against FPV of a gall extract from Guiera senegalensis was determined. Three viral isolates were obtained from suspected fowlpox cases after passage in embryonating chicken eggs and their poxviral identity confirmed by electron microscopy. All isolates were found to be pathogenic for chicks and all grew well in cell culture. Polymerase chain reaction and sequencing of amplicons revealed sequences identical with those of other FPV strains. The most studied isolate was then employed for use in an antiviral assay. An aqueous acetone extract from the galls of G. senegalensis was found to inhibit both virus-induced pock formation and to reduce viral titre in embryonating chicken eggs. The suggested mechanism of action is the activation of the alternative complement pathway and the inhibition of FPV-induced cholesterogenesis in ovo by constituents of the gall extract.


Asunto(s)
Combretaceae/química , Virus de la Viruela de las Aves de Corral/efectos de los fármacos , Óvulo/virología , Tumores de Planta , Replicación Viral/efectos de los fármacos , Animales , Antivirales/farmacología , Antivirales/uso terapéutico , Burkina Faso , Embrión de Pollo , Viruela Aviar/tratamiento farmacológico , Extractos Vegetales/química , Extractos Vegetales/farmacología
11.
Onderstepoort J Vet Res ; 72(2): 111-8, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16137128

RESUMEN

Aqueous decoctions obtained from the galls of Guiera senegalensis were screened to determine their phytochemical composition and in vitro antiviral activity against fowlpox virus. In addition, we wanted to investigate the toxic effects, if any, of crude extracts in chickens. Steroids as well as cardiac glycosides not previously reported, an alkaloid, polyphenols and saponins were detected in the various fractions of organic solvents used for extracting the decoctions. Antiviral activity was determined by cytopathic effect inhibition assay in primary chicken embryo skin cells. The 50% inhibitory concentration (EC50) was shown to be 15.6 microg/ml. Toxicity for cells was established by determining the 50% cytotoxic concentration (CCy50). A value of 90 microg/ml and a selectivity index (CCy50/EC50) of 5.8 were obtained. In vivo studies of toxicity were performed in chickens that were dosed orally with decoctions of several concentrations for 2 weeks and then monitored for 3 months. No significant changes in several blood chemical parameters were obtained, except for a significant decline in SGOT levels in birds dosed with 100 mg/kg. These levels were nevertheless within the accepted normal range. The findings suggest that aqueous decoctions of galls from G. senegalensis are non-toxic for chickens when administered orally, even at a daily dose of 100 mg/kg for 14 days.


Asunto(s)
Antivirales/uso terapéutico , Pollos , Combretaceae/química , Viruela Aviar/tratamiento farmacológico , Fitoterapia/veterinaria , Extractos Vegetales/uso terapéutico , Administración Oral , Animales , Antivirales/toxicidad , Análisis Químico de la Sangre , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Virus de la Viruela de las Aves de Corral/efectos de los fármacos , Dosificación Letal Mediana , Hígado/efectos de los fármacos , Hígado/enzimología , Masculino , Extractos Vegetales/toxicidad , Tumores de Planta , Enfermedades de las Aves de Corral/tratamiento farmacológico , Distribución Aleatoria
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