RESUMEN
Natural selection generally favours phenotypic variability in camouflaged organisms, whereas aposematic organisms are expected to evolve a more uniform warning coloration. However, no comprehensive analysis of the phenotypic consequences of predator selection in aposematic and cryptic species exists. Using state-of-the-art image analysis, we examine 2800 wing images of 82 moth species accessed via three online museum databases. We test whether anti-predator strategy (i.e., camouflage or aposematism) explains intraspecific variation in wing colour and pattern across northern hemisphere moths. In addition, we test two mutually non-exclusive, ecological hypotheses to explain variation in colour pattern: diel-activity or dietary-niche. In this work, taking into account phylogenetic relationships, moth phenotypic variability is best explained by anti-predator strategy with camouflaged moths being more variable in wing patterning than aposematic species.
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Mariposas Nocturnas , Animales , Filogenia , Variación Biológica Poblacional , Selección Genética , Conducta PredatoriaRESUMEN
A comparative sustainability study of bioethanol production from selected starchy feedstocks that are abundantly available was carried out in this work. This is to ensure the safe, reliable, and efficient production and consumption of fuel-grade bioethanol. The analysis utilised the established economic minimum bioethanol plant capacity of 158,000 m3/annum. The processing flowsheet model utilised was the same for each feedstock. The sustainability study's economic, environmental, and energy perspectives were investigated. The economic and environmental indices were assessed using Superpro Designer and openLCA sustainability software, respectively. Exergy and lost work were subsequently estimated manually with Microsoft Excel. The economic analyses showed that the plants using cassava and sweet potato initially had the highest return on investment (ROI) of 64.41 and 41.96% respectively at a minimum of 80% plants' capacity utilisation. The break-even point occurs at a bioethanol price of $3.27 per gallon, beyond which positive net present values were obtained for the four processes. The least profitable plant was based on sorghum recording an ROI value of 34.11%. The environmental assessment on the four selected feedstocks showed that the processes based on cassava, corn, sweet potato, and sorghum recorded encouraging global warming potential (GWP) of 0.2452, 0.2067, 2.5261, and 0.2099 kg CO2 equivalent respectively. Cassava and corn emerged as the two most economically viable feedstocks when economic parameters were adjusted to include pollutants emission/discharge costs but with a slight decrease in profitability indices. The lost work analyses showed that distillation columns were the least energy-efficient units in the four bioethanol production routes assessed, recording loss work of about 61, 68, 34, and 49 MW for cassava, sweet potato, corn, and sorghum processing plants respectively. However, the net energy balance (NEB) and energy renewability results of the four production routes showed that the processes utilising the four selected starchy biomass feedstocks are more sustainable compared to fossil fuels.
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Ipomoea batatas , Sorghum , Etanol , Biomasa , Grano Comestible , Almidón , BiocombustiblesRESUMEN
Vision is a vital attribute to foraging, navigation, mate selection and social signalling in animals, which often have a very different colour perception in comparison to humans. For understanding how animal colour perception works, vision models provide the smallest colour difference that animals of a given species are assumed to detect. To determine the just-noticeable-difference, or JND, vision models use Weber fractions that set discrimination thresholds of a stimulus compared to its background. However, although vision models are widely used, they rely on assumptions of Weber fractions since the exact fractions are unknown for most species. Here, we test; i) which Weber fractions in long-, middle- and shortwave (i.e. L, M, S) colour channels best describe the blue tit (Cyanistes caeruleus) colour discrimination, ii) how changes in hue of saturated colours and iii) chromatic background noise impair search behaviour in blue tits. We show that the behaviourally verified Weber fractions on achromatic backgrounds were L: 0.05, M: 0.03 and S: 0.03, indicating a high colour sensitivity. In contrast, on saturated chromatic backgrounds, the correct Weber fractions were considerably higher for L: 0.20, M: 0.17 and S: 0.15, indicating a less detailed colour perception. Chromatic complexity of backgrounds affected the longwave channel, while middle- and shortwave channels were mostly unaffected. We caution that using a vision model whereby colour discrimination is determined in achromatic viewing conditions, as they often are, can lead to misleading interpretations of biological interactions in natural - colourful - environments.
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Visión de Colores , Pájaros Cantores , Animales , Percepción de Color , HumanosRESUMEN
The production, optimization, and characterization of exopolysaccharide (EPS) from Weissella confusa OF126 and the in-vitro probiotic potentials of this strain was investigated. The EPS produced on sucrose modified-MRS broth was characterized. The purified EPS had an average molecular weight of 1.1â¯×â¯106â¯Da. HPLC analysis revealed the presence of glucose monomers, indicating its homopolysaccharide nature. The structural characteristics of the EPS were investigated by FTIR, and NMR spectroscopy. FTIR spectroscopy revealed the presence of hydroxyl, carboxyl, N-acetyl and amine groups. NMR analysis confirmed that the EPS contained α-(1â¯ââ¯6) linkage and α-(1â¯ââ¯3) branched linkage. The EPS showed strong in-vitro antioxidant activity. Four significant factors were optimized using Central Composite Design (CCD) and Response Surface Methodology (RSM). The predicted optimum conditions for EPS production were cultivation time (48.50â¯h), sucrose concentration (24.00â¯g/L), pH (7.00) and yeast extract (2.50%).The EPS produced was predicted to be 3.10â¯g/L, while the experimental yield was 3.00â¯g/L. This strain was found to possess desirable probiotic attributes by its ability to survive at pHâ¯2.0 and in the presence of bile salts (0.50% (w/v)) for 4â¯h. The results obtained from this study demonstrate W. confusa OF126 as a promising probiotic and the EPS produced can find useful applications in industries.
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Antioxidantes/química , Polisacáridos/química , Probióticos/química , Weissella/química , Antioxidantes/aislamiento & purificación , Ácidos y Sales Biliares/química , Glucosa/química , Humanos , Polisacáridos/aislamiento & purificación , Probióticos/aislamiento & purificaciónRESUMEN
Thirty-two lactic acid bacteria (LAB) isolates were obtained from fermenting cassava mash and wara (African soft cheese) and screened for their resistance to cadmium and lead toxicities at 550-1050 mg l-1 and probiotic potentials. Four LAB strains that tolerated the heavy metals at 1050 mg l-1 were selected for antioxidative capacities, tolerance to acid, bile salts and simulated gastric and intestinal tract and safety status. The results revealed that Weissella cibaria WD2 and Lactobacillus plantarum CaD1 exhibited comparatively higher antioxidative capacities, survived in simulated gastric and intestinal transit, tolerated acid and bile salt and possessed safety status. The two strains were employed for the in vivo studies, which was monitored in male albino Wistar rats using skim milk as a carrier for the cultures over a period of 28 days. The rats given the cultures of W. cibaria WD2 and L. plantarum CaD1 in addition with the administration of heavy metals had improved renal and hepatic impairment, while damage was observed in rats fed with cadmium and lead only. Weissella cibaria WD2 and L. plantarum CaD1 demonstrated probiotic potentials and safety status. These strains can be used to effectively amend hepatic and renal histopathological alterations in rats caused by ingestion of cadmium and lead. SIGNIFICANCE AND IMPACT OF THE STUDY: This present study highlights the presence of lactic acid bacteria (LAB) from traditional fermented foods that were cadmium and lead resistant and possessed probiotic potentials. Weissella cibaria WD2 and Lactobacillus plantarum CaD1 selected for the in vivo studies ameliorated the build-up of cadmium and lead in the organs of the animals. This indicated that good cadmium and lead binding and probiotic lactic acid bacteria can be used to prevent exposure to these heavy metals.
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Biodegradación Ambiental , Cadmio/metabolismo , Lactobacillus plantarum/metabolismo , Intoxicación por Plomo/prevención & control , Plomo/metabolismo , Probióticos/farmacología , Weissella/metabolismo , Animales , Ácidos y Sales Biliares/metabolismo , Cadmio/toxicidad , Fermentación , Riñón/efectos de los fármacos , Riñón/microbiología , Lactobacillus plantarum/efectos de los fármacos , Lactobacillus plantarum/aislamiento & purificación , Plomo/toxicidad , Hígado/efectos de los fármacos , Hígado/microbiología , Manihot/microbiología , Ratas , Ratas Wistar , Weissella/efectos de los fármacos , Weissella/aislamiento & purificaciónRESUMEN
AIMS: To determine the starter culture and multifunctional potentials of yeast strains from some cereal-based Nigerian traditional fermented food products. METHODS AND RESULTS: Yeast isolates were screened for enzyme production and identified by sequencing the D1/D2 region of 26S rDNA. Pichia kluyveri LKC17, Issatchenkia orientalis OSL11, Pichia kudriavzevii OG32, Pichia kudriavzevii ROM11 and Candida tropicalis BOM21 exhibited the highest protease, lipase and phytase activity. They were selected and further evaluated for gastrointestinal survival and adherence ability. Although strain-specific, they retained viability at 37°C and showed survival at pH 2·0., I. orientalis OSL11 showed the highest survival at 2% bile salts concentration and P. kudriavzevii ROM11 showed the least survival. The yeast strains showed strong autoaggregation ability (81·24-91·85%) and hydrophobicity to n-hexadecane (33·61-42·30%). The highest co-aggregation ability was detected for P. kudriavzevii OG32 and Escherichia coli (71·57%). All the yeast strains removed cholesterol in the range of 49·03-74·05% over 48 h and scavenged for free radicals in methanol reaction system. CONCLUSIONS: In this study, we isolated new yeast strains with multifunctional potentials that can be used as functional starter cultures to produce cereal-based probiotic products. SIGNIFICANCE AND IMPACT OF THE STUDY: The development of probiotic yeast strains as starter culture to improve the quality attributes and confer functional value on cereal-based traditional fermented foods is beneficial.
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Microbiología de Alimentos , Probióticos/aislamiento & purificación , Levaduras/aislamiento & purificación , Colesterol/metabolismo , Grano Comestible/microbiología , Fermentación , Datos de Secuencia Molecular , Nigeria , Probióticos/clasificación , Probióticos/metabolismo , Levaduras/clasificación , Levaduras/genética , Levaduras/metabolismoRESUMEN
OBJECTIVE: This cross-sectional study was to determine the prevalence and characterization of high-risk HPV genotypes circulating among adolescents in Ouagadougou. METHODS: From September to December 2013, 200 adolescents recruited from a youth counseling center have voluntarily accepted a swab of the endocervical canal. The identification of the genotypes of the human Papillomavirus (HPV) was performed by real-time polymerase chain reaction technique. RESULTS: The mean age of adolescents was 18.7±0.7 years and 83/200 adolescents were positive for at least one high-risk genotype HPV a prevalence of 41.5%. Twelve genotypes corresponding to 136 infections were characterized: HPV 52 (22.8%), HPV 59 (14.0%), HPV 39 (13.2%), HPV 35 (10.3%), HPV 51 (10.3%), HPV 56 (8.8%), HPV 16 (5.2%), HPV 18 (5.2%), HPV 58 (4.4%), HPV 31 (3.6%), HPV 45 (1.5%), HPV 33 (0.7%). Multiple infections (2-5 virus) statistically associated with age (p=0.0318) was detected in 42.2% of infected females. If the number of sexual partners was statistically associated with the porting of HPV (OR=2.18; 95% CI=1.17 to 4.09), early sexual intercourse and the recent change of sexual partner were not (p>0,05) CONCLUSION: The prevalence of carriage of HPV in this study is high, as described in young people at the start of sexual activity. Identified genotypes are different from those targeted by prophylactic vaccines currently available. A larger study to map genotypes of high-risk HPV circulating in West Africa is necessary for a suitable vaccine.
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Papillomaviridae/genética , Infecciones por Papillomavirus/epidemiología , Adolescente , Burkina Faso/epidemiología , Femenino , Humanos , Papillomaviridae/clasificación , Infecciones por Papillomavirus/diagnóstico , Prevalencia , RiesgoRESUMEN
Aflatoxin B1 (AFB1) is a carcinogenic mycotoxin produced by Aspergilli of the section Flavi that may contaminate food, in the field or during storage. Cassava represents an important staple food in sub-Saharan Africa. The analysis of aflatoxigenic fungi in 36 cassava samples obtained from producers in Benin indicated that 40% were contaminated by Aspergilli of the section Flavi. Upon morphological and molecular characterization of the 20 isolates, 16 belonged to Aspergillus flavus, 2 to Aspergillus parvisclerotigenus and 2 to Aspergillus novoparasiticus. This is the first time that this latter species is isolated from food. Although most of these isolates were toxigenic on synthetic media, no AFB1 contamination was observed in these cassava samples. In order to determine the action of cassava on AFB1 synthesis, a highly toxigenic strain of A. flavus, was inoculated onto fresh cassava and despite a rapid development, no AFB1 was produced. The anti-aflatoxin property was observed with cassava from different geographical origins and on other aflatoxigenic strains of the section Flavi, but it was lost after heating, sun drying and freezing. Our data suggest that fresh cassava is safe regarding AFB1 contamination, however, processing may alter its ability to block toxinogenesis leading to secondary contamination.
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Aflatoxina B1/metabolismo , Aspergillus flavus/aislamiento & purificación , Manihot/microbiología , Verduras/microbiología , Aspergillus/clasificación , Aspergillus/aislamiento & purificación , Aspergillus/metabolismo , Aspergillus flavus/clasificación , Aspergillus flavus/metabolismo , Contaminación de Alimentos/análisisRESUMEN
While appendicitis remains one of the commonest surgical diseases, there are relatively few reports following renal transplantation. A 33-year-old man was admitted with diarrhea, fever, and epigastric pain 7 years following a cadaveric renal transplant. CT scanning confirmed a diagnosis of appendicitis which was removed within 24 hours of admission. Histology and blood cultures following surgery confirmed Salmonella type b appendicitis. Patient was safely discharged home 5 days following hospital admission.
RESUMEN
Twenty-five villages of Northern Benin were surveyed to identify the constraints of yam chips production, assess the diversity of storage insects on yam chips, and document farmers' perception of their impacts on the stocks and their traditional management practices. Damages due to storage insects (63.9% of responses) and insufficiency of insect-resistant varieties (16.7% of responses) were the major constraints of yam chips production. Twelve insect pest species were identified among which Dinoderus porcellus Lesne (Coleoptera, Bostrichidae) was by far the most important and the most distributed (97.44% of the samples). Three predators (Teretrius nigrescens Lewis, Xylocoris flavipes Reuter, and Alloeocranum biannulipes Montrouzier & Signoret) and one parasitoid (Dinarmus basalis Rondani) all Coleoptera, Bostrichidae were also identified. The most important traditional practices used to control or prevent insect attack in yam chips were documented and the producers' preference criteria for yam cultivars used to produce chips were identified and prioritized. To further promote the production of yam chips, diversification of insect-resistant yam varieties, conception, and use of health-protective natural insecticides and popularization of modern storage structures were proposed.
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Dioscorea/parasitología , Análisis de los Alimentos/estadística & datos numéricos , Contaminación de Alimentos/estadística & datos numéricos , Almacenamiento de Alimentos/estadística & datos numéricos , Insectos/clasificación , Insectos/patogenicidad , Animales , BeninRESUMEN
Mycotoxins contamination in some agricultural food commodities seriously impact human and animal health and reduce the commercial value of crops. Mycotoxins are toxic secondary metabolites produced by fungi that contaminate agricultural commodities pre- or postharvest. Africa is one of the continents where environmental, agricultural and storage conditions of food commodities are conducive of Aspergillus fungi infection and aflatoxin biosynthesis. This paper reviews the commodity-wise aetiology and contamination process of aflatoxins and evaluates the potential risk of exposure from common African foods. Possible ways of reducing risk for fungal infection and aflatoxin development that are relevant to the African context. The presented database would be useful as benchmark information for development and prioritization of future research. There is need for more investigations on food quality and safety by making available advanced advanced equipments and analytical methods as well as surveillance and awareness creation in the region.
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Aflatoxinas/toxicidad , Países en Desarrollo , Contaminación de Alimentos , Enfermedades Transmitidas por los Alimentos/etiología , Aflatoxinas/análisis , Aflatoxinas/metabolismo , África del Sur del Sahara , Agricultura/legislación & jurisprudencia , Agricultura/métodos , Animales , Contaminación de Alimentos/prevención & control , Manipulación de Alimentos/legislación & jurisprudencia , Inspección de Alimentos/legislación & jurisprudencia , Calidad de los Alimentos , Enfermedades Transmitidas por los Alimentos/microbiología , Enfermedades Transmitidas por los Alimentos/prevención & control , Enfermedades Transmitidas por los Alimentos/veterinaria , Hongos/crecimiento & desarrollo , Hongos/metabolismo , Humanos , Legislación Alimentaria , Interacciones Microbianas , Micotoxinas/análisis , Micotoxinas/toxicidad , Control de Plagas/legislación & jurisprudencia , Control de Plagas/métodosRESUMEN
AIM: To identify enterococci from the fermentation of milk for the production of nono, an African fermented dairy product, to determine the technological properties for suitability as starter cultures and safety as probiotics. METHODS AND RESULTS: Enterococcus faecium CM4 and Enterococcus faecium 2CM1 were isolated from raw cow's milk. The strains were phenotypically and genotypically identified. Technological properties, safety investigations, in vitro adherence properties and antimicrobial characteristics were carried out. Strong acidification and tolerance to bile salts were recorded. The strains were bile salts hydrolytic positive and no haemolysis. There was no resistance to clinically relevant antibiotics. The strains exhibited adherence to human collagen type IV, human fibrinogen and fibronectin. The bacteriocins were active against Bacillus cereus DSM 2301, Bacillus subtilis ATCC 6633, Micrococcus luteus and Listeria monocytogenes. Bacteriocins were stable at pH 4-9 and on treatment with lipase, catalase, α-amylase and pepsin, while their activity was lost on treatment with other proteases. The bacteriocins produced were heat stable at 100°C for 10 min. The bacteriocin produced by the strains was identified as enterocin A. CONCLUSIONS: The E. faecium strains in this study exhibited probiotic activity, and the safety investigations indicate their suitability as good candidates for a starter culture fermentation process. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of bacteriocin-producing E. faecium strains as starter cultures in fermented foods is beneficial but, however, their safety investigations as probiotics must be greatly emphasized.
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Bacteriocinas/aislamiento & purificación , Enterococcus faecium/aislamiento & purificación , Leche/microbiología , Probióticos , Animales , Adhesión Bacteriana , Bacteriocinas/análisis , Ácidos y Sales Biliares/farmacología , Productos Lácteos/microbiología , Enterococcus faecium/clasificación , Enterococcus faecium/efectos de los fármacos , Fermentación , Genes Bacterianos , Pruebas de Sensibilidad Microbiana , Nigeria , Estabilidad ProteicaRESUMEN
The ethanol extracts obtained from Psidium guajava, Flacourtia flavescens Boswellia dalzielii, Ficus exasperata, Pavetta corymbosa and Hybanthus enneaspermus, six species traditionally used in Benin to treat several infectious diseases, were evaluated for their in vitro antimicrobial activity against Staphylococcus aureus, Enteroccocus feacalis, Escherichia coli and Pseudomonas aeruginosa. The minimum inhibitory concentration of extracts was determinate using the microplate dilution method. The presence of major phytoconstituents was detected qualitatively. The diphenylpicrylhydrazine radical scavenging activity was also performed. The extracts exhibited antibacterial activities against the tested bacteria. Boswellia dalzielii, Psidium guayava, Pavetta corymbosa and Flacourtia flavescens exibited the lowest minimum inhibitory concentration values (0.313-2.5 mg mL(-1)). Pseudomonas aeruginosa was the lest sensitive microorganism with MIC values higher than 10 mg mL(-1). In antioxidant assay the crude extracts of B. dalzielii and P. corymbosa appeared to be as potent as quercetol with an inhibition percentage of 83 and 75.3% at 10 microg mL(-1) which is comparable to 75.9% for quercetol at the same concentration.
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Antibacterianos/farmacología , Extractos Vegetales/farmacología , Plantas Medicinales , Benin , Boswellia , Ficus , Mercaptopurina/análogos & derivados , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/efectos de los fármacos , Psidium , Salicaceae , Staphylococcus aureus/efectos de los fármacosRESUMEN
Although salmonellosis is a common endemo-epidemic disease in Benin, there is a paucity of data about it. The purpose of this cross-sectional study was to determine the incidence of major salmonellosis requiring hospitalizaton and to describe its epidemiological, clinical, and serologic features as well as treatment and outcome. Consecutive cases observed at the Medical Department of Parakou University Hospital in Benin between January 1, 2005 and December 31 2007 were included. Salmonellosis was defined on the basis of clinical and serological criteria. Among the 2,520 patients hospitalized during the study period, salmonellosis was diagnosed in 135 (5.4% [95% CI 4.5%-6.3%]). Highest incidences were observed in January, July, October and November. The main symptoms were headache, fever, fatigue and abdominal pain. The Salmonella typhi serotype was identified in 94.8% of patients. Two patients presented co-infection, i.e., Salmonella typhi with paratyphi A in one case and Salmonella typhi with paratyphi B in the other. Fluoroquinolones were used for treatment in 79.3% of patients. Outcome was favorable in 62.2%. The main complications were,typhoid digestive perforation in 11.1%, and gastrointestinal bleeding in 8.1%. The mortality rate was 4.4% (n=6). These data are consistent with previous reports in the literature and confirm the frequency and severity of salmonellosis in Benin.
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Infecciones por Salmonella/diagnóstico , Infecciones por Salmonella/epidemiología , Infecciones por Salmonella/terapia , Adolescente , Adulto , Anciano , Benin/epidemiología , Estudios Transversales , Diagnóstico Tardío/estadística & datos numéricos , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Pronóstico , Infecciones por Salmonella/sangre , Pruebas Serológicas , Adulto JovenRESUMEN
Biosorption of lead(II) ions from aqueous solution onto the seed husk of Calophyllum inophyllum was investigated in a batch system. Equilibrium, thermodynamics and kinetic studies were conducted by considering the effects of pH, initial metal ion concentration, contact time, and temperature. The results showed that the uptake of the metal ions increased with increase in initial metal ion concentration. The pH for optimum adsorption was 4 for the Pb(II) ions (q=4.86 mg/g and 97.2% adsorption). Langmuir isotherm described the biosorption of Pb(II) ions onto the biomass (R(2)=0.9531) better than the Freundlich model (R(2)=0.7984), and the Temkin model (R(2)=0.8761). Biosorption kinetics data obtained for the metal ions sorption were fitted using pseudo-first-order and pseudo-second-order. It was found that the kinetics data fitted well into the pseudo-second-order kinetics. Thermodynamic parameters such as Gibbs free energy (DeltaG), standard enthalpy (DeltaH) and standard entropy (DeltaS) were evaluated. The result showed that biosorption of the metal ion onto C. inophyllum biomass was spontaneous and endothermic in nature. The results of FTIR (Fourier-transform infrared spectroscopy) revealed that carboxyl, amine, and hydroxyl groups on the biomass surface were involved in the adsorption of Pb(II) ions.
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Biodegradación Ambiental , Calophyllum/metabolismo , Plomo/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Cinética , Semillas/metabolismo , TermodinámicaRESUMEN
Staphylococcus aureus infections are widely prevalent in West Africa and are often associated with urinary tract infections (UTIs). Virulence factors from S. aureus have rarely been described for such infections. The purpose of the current study was to determine the prevalence of toxins and adhesion factors obtained from S. aureus isolated from presumed primary UTIs at the Cotonou University Hospital (CUH) in Benin as compared with the Strasbourg University Hospital (SUH) in France. Both ambulatory and hospitalised patients were included in the study. Sixty-five independent strains of S. aureus from CUH and 35 strains from SUH were obtained over a four-month period. Virulence factors were characterised by immunodetection or multiplex polymerase chain reaction, and meticillin susceptibility was recorded. Approximately 50% of all isolates produced at least one enterotoxin. No isolate from SUH produced Panton-Valentine leucocidin (PVL), whereas 21.5% of the S. aureus isolates from CUH produced PVL (P<0.01). Six of 14 (43%) PVL-positive isolates were meticillin-resistant. At SUH, the incidence of MRSA (57%) was significantly higher (P<0.01) than at CUH (14%). Genes encoding clumping factor B, and elastin and laminin binding proteins were detected in almost all isolates (80%), irrespective of the geographical origin. The results for elastin binding protein differed significantly from published data regarding isolates from other clinical origins. Staphylococcal toxins and adhesion factors may be important in the physiopathology of UTI.
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Infecciones Estafilocócicas , Staphylococcus aureus/genética , Infecciones Urinarias/microbiología , Factores de Virulencia/genética , Adhesinas Bacterianas/genética , Adhesinas Bacterianas/aislamiento & purificación , Adulto , Anciano , Benin , Enterotoxinas/genética , Enterotoxinas/aislamiento & purificación , Femenino , Genotipo , Humanos , Pacientes Internos , Masculino , Resistencia a la Meticilina/genética , Persona de Mediana Edad , Pacientes Ambulatorios , Estudios Prospectivos , Staphylococcus aureus/patogenicidad , Factores de Virulencia/metabolismoRESUMEN
INTRODUCTION: The pathogenic capacity of S. aureus is related.to the production of many virulence factors of which the coagulase. Several genotypes of coagulase were described and are associated to various populations of S. aureus. According the susceptibility to methicillin, methicillin-resistant strains of S. aureus, are described. The aim of this subject was to study the coagulase expression of Staphylococcus aureus according to the site of infection, patient origin and the resistance against methicillin. MATERIAL AND METHODS: The study is related about 180 strains of S. aureus collected in the three University Teaching Hospital of Abidjan. S. aureus are identified with laboratory classical methods. Coagulase delay was determined by the test of the coagulase on citrated rabbit plasma at 2, 4 and 18 hours. The resistance against methicillin was researched by disc diffusion agar technique. RESULTS: In 60% of cases, the bacterial strains gave a coagulum at the end of four hours, fast coagulase, against 40% of strains whose coagulating activity appeared at 18 h, slow coagulase. Fast coagulase strains are isolated from the majority of infections (55% to 71%), in hospital patients (66%) and in paediatrics (58%). Fast coagulase strains are methicillin-resistant in 65% of cases against 48.5% of methicillin-susceptible and low coagulase strains (p < 0.0001). CONCLUSION: According to the production lead time of the coagulase, fast coagulase and slow coagulase variants of S. aureus coexisted. The expression of the coagulase is not related to the site of infection and the origin of the patients. On the other hand, the type of coagulase is associated to resistance of methicillin. However, the time of formation of the coagulum typed by the test of the coagulase, didn't constitute a sufficient discriminating factor in the medical following and the treatment of infections caused by S. aureus.
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Coagulasa/metabolismo , Staphylococcus aureus/metabolismo , Técnicas de Tipificación Bacteriana , Côte d'Ivoire , Humanos , Resistencia a la MeticilinaRESUMEN
OBJECTIVES: Over a 6-month period, extended-spectrum betalactamase (ESBL)-producing isolates of Escherichia coli (EC) were collected from in-patients and their environment at the Zou-Collines Hospital Centre (CHDZ/C) in Benin. The aim of this study was to determine the incidence of ESBL and to describe their phenotypic susceptibility to antibiotics in a secondary hospital (500 beds) in Benin. METHODS: From 15 May to 15 November 2005, clinical informations and samples were collected from patients suspected to have nosocomial infections. The isolates were identified, tested for antimicrobial susceptibility and analysed for the presence of ESBL genes blaTEM and blaSHV by PCR. RESULTS: One hundred ninety-seven enterobacteria were isolated from the clinical samples of 342 patients, these isolates included 143 EC and 32/143 (22%) of these isolates produced ESBL. Forty-six EC were isolated from the environment and 7 (15%) of them produced ESBL. Except for Imipenem for which the difference was not significant, the isolates producing ESBL were more resistant to the other antibiotics (especially to third generation cephalosporins: Ceftriaxone, Cefotaxime, Ceftazidime (P<0.00001)) than non-ESBL producing isolates. Both ESBL genes blaSHV and blaTEM were identified in the EC ESBL strains from patient and from the environment. CONCLUSION: This study shows the presence of ESBL genes among EC in various wards of the CHDZ/C hospital proving that there is a need to implement a strict hospital infection control program and a regular surveillance of resistance to antimicrobial agents.
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Antibacterianos/uso terapéutico , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/epidemiología , Escherichia coli/genética , beta-Lactamasas/metabolismo , Benin/epidemiología , Farmacorresistencia Bacteriana , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , Escherichia coli/patogenicidad , Humanos , Incidencia , Pruebas de Sensibilidad Microbiana , Reacción en Cadena de la PolimerasaRESUMEN
The widening gap between supply and demand for renal transplantation has prompted many centers to use donors after cardiac death. Some of these donors exhibit signs of acute renal failure (ARF) prior to cardiac arrest. Concern has been expressed about poor quality of graft function from such donors. In response to this perception, we reviewed 49 single renal transplant recipients from category III donors after cardiac death between 1998 and 2005, at our center. All kidneys but one had hypothermic machine perfusion and viability testing prior to transplantation. According to the RIFLE criteria, nine recipients had kidneys from donors with "low severity pre-arrest ARF". The remainder of the recipients were used as control group. There was no statistical significant difference in delayed graft function and rejection rates between these two groups. Recipients GFR at 12 months was 44.4 +/- 17.1 and 45.2 +/- 14.7 (mL/min/1.73m(2)) from donors with ARF and without ARF, respectively (p = 0.96). In conclusion, low severity ARF in kidneys from controlled after cardiac death donors can be a reversible condition after transplantation. Short-term results are comparable to the kidneys from same category donors without renal failure, providing that some form of viability assessment is implemented prior to transplantation.
Asunto(s)
Lesión Renal Aguda/diagnóstico , Muerte , Trasplante de Riñón , Riñón/fisiología , Donantes de Tejidos/provisión & distribución , Adulto , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Obtención de Tejidos y Órganos/métodos , Resultado del TratamientoRESUMEN
Graft thrombosis is one of the most devastating complications of transplantation. In obtaining consent prior to transplant, it is useful to share potential risk factors with the recipient. In order to do this, we explored the impact of different risk factors that could contribute to this complication. Using multivariate analysis we found that neither multiple vessels nor vascular injury had a bearing on the risk of graft thrombosis but atheroma did (P < .02).