Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
1.
Front Cell Infect Microbiol ; 13: 1198115, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37434783

RESUMO

Introduction: Infection in diabetic foot ulcers (DFUs) is one of the major complications associated with patients with diabetes. Staphylococcus aureus is the most common offending pathogen in patients with infected DFU. Previous studies have suggested the application of species-specific antibodies against S. aureus for diagnosis and monitoring treatment response. Early and accurate identification of the main pathogen is critical for management of DFU infection. Understanding the host immune response against species-specific infection may facilitate diagnosis and may suggest potential intervention options to promote healing infected DFUs. We sought to investigate evolving host transcriptome associated with surgical treatment of S. aureus- infected DFU. Methods: This study compared the transcriptome profile of 21 patients with S. aureus- infected DFU who underwent initial foot salvage therapy with irrigation and debridement followed by intravenous antibiotic therapy. Blood samples were collected at the recruitment (0 weeks) and 8 weeks after therapy to isolate peripheral blood mononuclear cells (PBMCs). We analyzed the PBMC expression of transcriptomes at two different time points (0 versus 8 weeks). Subjects were further divided into two groups at 8 weeks: healed (n = 17, 80.95%) versus non-healed (n = 4, 19.05%) based on the wound healing status. DESeq2 differential gene analysis was performed. Results and discussion: An increased expression of IGHG1, IGHG2, IGHG3, IGLV3-21, and IGLV6-57 was noted during active infection at 0 weeks compared with that at 8 weeks. Lysine- and arginine-rich histones (HIST1H2AJ, HIST1H2AL, HIST1H2BM, HIST1H3B, and HIST1H3G) were upregulated at the initial phase of active infection at 0 weeks. CD177 and RRM2 were also upregulated at the initial phase of active infection (0 weeks) compared with that at 8 weeks of follow-up. Genes of heat shock protein members (HSPA1A, HSPE1, and HSP90B1) were high in not healed patients compared with that in healed patients 8 weeks after therapy. The outcome of our study suggests that the identification of genes evolution based on a transcriptomic profiling could be a useful tool for diagnosing infection and assessing severity and host immune response to therapies.


Assuntos
Doenças Transmissíveis , Diabetes Mellitus , Pé Diabético , Staphylococcus aureus Resistente à Meticilina , Humanos , Transcriptoma , Pé Diabético/genética , Leucócitos Mononucleares , Staphylococcus aureus , Histonas
2.
Int J Mol Sci ; 23(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36362318

RESUMO

Bone absorption is necessary for the maintenance of bone homeostasis. An osteoclast (OC) is a monocyte-macrophage lineage cell that absorbs bone tissue. Extracellular signal-regulated kinases (ERKs) are known to play important roles in regulating OC growth and differentiation. In this study, we examined specific downstream signal pathways affected by ERK inhibition during OC differentiation. Our results showed that the ERK inhibitors PD98059 and U0126 increased receptor activator of NF-κB ligand (RANKL)-induced OC differentiation in RAW 264.7 cells, implying a negative role in OC differentiation. This is supported by the effect of ERK2-specific small interfering RNA on increasing OC differentiation. In contrast to our findings regarding the RAW 264.7 cells, the ERK inhibitors attenuated the differentiation of bone marrow-derived cells into OCs. The ERK inhibitors significantly increased the phosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK) but not the activation of p38 MAPK, Lyn, and mTOR. In addition, while the ERK inhibition increased the expression of the RANKL receptor RANK, it decreased the expression of negative mediators of OC differentiation, such as interferon regulatory factor-8, B-cell lymphoma 6, and interferon-γ. These dichotomous effects of ERK inhibition suggest that while ERKs may play positive roles in bone marrow-derived cells, ERKs may also play negative regulatory roles in RAW 264.7 cells. These data provide important information for drug development utilizing ERK inhibitors in OC-related disease treatment.


Assuntos
Proteínas Quinases Ativadas por AMP , Reabsorção Óssea , Camundongos , Animais , Proteínas Quinases Ativadas por AMP/metabolismo , Células RAW 264.7 , Ligante RANK/farmacologia , Ligante RANK/metabolismo , Osteoclastos/metabolismo , Osteogênese , Diferenciação Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Reabsorção Óssea/metabolismo
3.
Hum Resour Health ; 20(1): 76, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36303151

RESUMO

BACKGROUND: Emigration of Nigerian doctors, including those undergoing training, to the developed countries in Europe and Americas has reached an alarming rate. OBJECTIVE: This study aimed at assessing the prevalence, pattern, and determinants of migration intention among doctors undergoing residency and internship training programmes in the public tertiary hospitals in Ekiti state, Nigeria. METHODS: This was a cross-sectional study using a quantitative data collected from 182 doctors undergoing residency and internship training at the two tertiary hospitals. An adapted semi-structured questionnaire was used to collect information on migration intention among the eligible respondents. Univariate, bivariate and multivariate data analyses were done. The level of significance was determined at p-value < 0.05. RESULTS: Majority (53.9%) of doctors undergoing training were between 30-39 years, and the mean age was 33.2 ± 5.7 years, male respondents were 68.1%, and 53.8% of the respondents were married. The proportion of doctors undergoing training who had the intention to migrate abroad to practice was 74.2%. A higher proportion of the internship trainees, 79.5%, intended to migrate abroad to practice while the proportion among the resident doctors, was 70.6%. Among the respondents who intended to migrate abroad to practice, 85(63%) intend to migrate abroad within the next 2 years, while the preferred countries of destination were the United Kingdom 65(48.2%), Canada 29 (21.5%), Australia 20 (14.8%) and the United States 18(13.3%). Seventy percent of respondents who intend to migrate abroad had started working on implementation of their intention to migrate abroad. The majority of the junior resident doctors, 56(72.7%), intend to migrate abroad compared with the senior resident doctors, 21(27.3%), (χ2 = 14.039; p < 0.001). The determinants of migration intention are the stage of residency training and level of job satisfaction. CONCLUSION: There is a high prevalence of migration intention among the doctors undergoing training in the public tertiary hospitals in Ekiti State, Nigeria, with the majority already working on their plans to migrate abroad. Doctors undergoing training who are satisfied with their job and those who are in the senior stage of residency training programme are less inclined to migrate abroad. RECOMMENDATIONS: The hospital management in the tertiary hospitals should develop retention strategies for human resources for health, especially doctors undergoing training in their establishment, to avert the possible problems of dearth of specialists in the tertiary health facilities. Also, necessary support should be provided for the residency training programme in the tertiary health institutions to make transition from junior to senior residency stage less strenuous.


Assuntos
Intenção , Internato e Residência , Masculino , Humanos , Adulto , Escolha da Profissão , Nigéria , Estudos Transversais , Prevalência , Centros de Atenção Terciária , Inquéritos e Questionários
4.
Sensors (Basel) ; 21(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203119

RESUMO

Embedded systems technology is undergoing a phase of transformation owing to the novel advancements in computer architecture and the breakthroughs in machine learning applications. The areas of applications of embedded machine learning (EML) include accurate computer vision schemes, reliable speech recognition, innovative healthcare, robotics, and more. However, there exists a critical drawback in the efficient implementation of ML algorithms targeting embedded applications. Machine learning algorithms are generally computationally and memory intensive, making them unsuitable for resource-constrained environments such as embedded and mobile devices. In order to efficiently implement these compute and memory-intensive algorithms within the embedded and mobile computing space, innovative optimization techniques are required at the algorithm and hardware levels. To this end, this survey aims at exploring current research trends within this circumference. First, we present a brief overview of compute intensive machine learning algorithms such as hidden Markov models (HMM), k-nearest neighbors (k-NNs), support vector machines (SVMs), Gaussian mixture models (GMMs), and deep neural networks (DNNs). Furthermore, we consider different optimization techniques currently adopted to squeeze these computational and memory-intensive algorithms within resource-limited embedded and mobile environments. Additionally, we discuss the implementation of these algorithms in microcontroller units, mobile devices, and hardware accelerators. Conclusively, we give a comprehensive overview of key application areas of EML technology, point out key research directions and highlight key take-away lessons for future research exploration in the embedded machine learning domain.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , Algoritmos , Computadores de Mão , Máquina de Vetores de Suporte
5.
Environ Int ; 148: 106378, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33508708

RESUMO

Low birth weight is an important risk factor for many co-morbidities both in early life as well as in adulthood. Numerous studies report associations between prenatal exposure to particulate matter (PM) air pollution and low birth weight. Previous systematic reviews and meta-analyses report varying effect sizes and significant heterogeneity between studies, but did not systematically evaluate the quality of individual studies or the overall body of evidence. We conducted a new systematic review to determine how prenatal exposure to PM2.5, PM10, and coarse PM (PM2.5-10) by trimester and across pregnancy affects infant birth weight. Using the Navigation Guide methodology, we developed and applied a systematic review protocol [CRD42017058805] that included a comprehensive search of the epidemiological literature, risk of bias (ROB) determination, meta-analysis, and evidence evaluation, all using pre-established criteria. In total, 53 studies met our inclusion criteria, which included evaluation of birth weight as a continuous variable. For PM2.5 and PM10, we restricted meta-analyses to studies determined overall as "low" or "probably low" ROB; none of the studies evaluating coarse PM were rated as "low" or "probably low" risk of bias, so all studies were used. For PM2.5, we observed that for every 10 µg/m3 increase in exposure to PM2.5 in the 2nd or 3rd trimester, respectively, there was an associated 5.69 g decrease (I2: 68%, 95% CI: -10.58, -0.79) or 10.67 g decrease in birth weight (I2: 84%, 95% CI: -20.91, -0.43). Over the entire pregnancy, for every 10 µg/m3 increase in PM2.5 exposure, there was an associated 27.55 g decrease in birth weight (I2: 94%, 95% CI: -48.45, -6.65). However, the quality of evidence for PM2.5 was rated as "low" due to imprecision and/or unexplained heterogeneity among different studies. For PM10, we observed that for every 10 µg/m3 increase in exposure in the 3rd trimester or the entire pregnancy, there was a 6.57 g decrease (I2: 0%, 95% CI: -10.66, -2.48) or 8.65 g decrease in birth weight (I2: 84%, 95% CI: -16.83, -0.48), respectively. The quality of evidence for PM10 was rated as "moderate," as heterogeneity was either absent or could be explained. The quality of evidence for coarse PM was rated as very low/low (for risk of bias and imprecision). Overall, while evidence for PM2.5 and course PM was inadequate primarily due to heterogeneity and risk of bias, respectively, our results support the existence of an inverse association between prenatal PM10 exposure and low birth weight.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Efeitos Tardios da Exposição Pré-Natal , Adulto , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Peso ao Nascer , Exposição Ambiental/análise , Feminino , Humanos , Lactente , Recém-Nascido , Exposição Materna/efeitos adversos , Material Particulado/análise , Gravidez , Efeitos Tardios da Exposição Pré-Natal/epidemiologia
6.
Nutrients ; 12(8)2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32806557

RESUMO

Postmenopausal osteoporosis is a common disorder resulting from increased osteoclastic activity. To determine the effect of Panax ginseng on postmenopausal osteoporosis, ovariectomized (OVX) mice were treated with 500 mg/kg/day P. ginseng extract (Pg) alone or in combination with hot water extract of Brassica oleracea (Bo) daily for 10 weeks, and the effect of the treatments on OVX-induced bone loss was examined. Bone weight, bone mineral density (BMD), osteoclast (OC) formation, OC marker expression, and biochemical parameters in blood were determined. OVX significantly increased body weight and decreased bone weight compared with those in the Sham group (p < 0.01). Pg or Bo alone did not affect OVX-induced bone loss, but a combination of Pg and Bo (Pg:Bo) recovered bone weight. The bones of OVX mice showed lower BMD than that of Sham mice, and the Pg:Bo = 3:1 restored the decreased BMD. Single treatment with Pg or Bo did not alter OC formation; however, the Pg:Bo = 3:1 inhibited OC formation. In addition, Pg and Bo lowered the OVX-induced elevation in blood glucose level. Thus, we suggest that Pg in combination with proper materials, such as Bo, might be a potential candidate treatment with minimal side effects protect against postmenopausal osteoporosis.


Assuntos
Densidade Óssea/efeitos dos fármacos , Brassica , Osteoporose Pós-Menopausa/prevenção & controle , Panax , Extratos Vegetais/administração & dosagem , Animais , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Humanos , Camundongos , Osteoclastos/efeitos dos fármacos , Osteoporose Pós-Menopausa/etiologia , Ovariectomia
7.
Free Radic Res ; 54(11-12): 894-905, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32183593

RESUMO

Osteoclasts (OCs) are multinucleated cells that are phylogenetically evolved from monocyte-macrophage lineage and are essential for skeletal coupling processes. During bone development, bone formation by osteoblasts and bone resorption by OCs are tightly coupled and are involved in bone homeostasis. Therefore, it is essential to understand the mechanisms that regulate OC differentiation in order to develop effective therapeutics for the treatment of OC-associated diseases. This study aimed to determine the molecular mechanisms regulating OC differentiation. The mitogen-activated protein kinases and extracellular signal-regulated kinase (ERK) are recognised to be crucial factors regulating OC differentiation and activation. RAW 264.7 cells were differentiated into OCs in the presence of RANKL and were treated with inhibitors of several signal pathways. Although PD98059 is an ERK inhibitor, it inhibited the phosphorylation of ERK, JNK, Akt, and Src kinase. PD98059 increased OC differentiation and expression of OC markers, such as TRAP, calcitonin receptor, and cathepsin K, and increased the expression of NFATc1. Moreover, it also increased the expression of glutamate-cysteine ligase and production of glutathione (GSH). Thus, we examined the involvement of GSH in OC differentiation and observed that GSH treatment alone increased the OC numbers and cotreatment with PD98059 further enhanced OC differentiation. Our results suggested that inhibition of the ERK pathway may promote OC differentiation via upregulation of GSH. These findings reveal that ERK and GSH modulate the signal pathway necessary for OC differentiation, and this may form the basis of a new therapeutic strategy for treating OC-related diseases.


Assuntos
Glutationa/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Ligante RANK/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Glutationa/biossíntese , Humanos , Camundongos , Células RAW 264.7 , Proteínas Recombinantes/farmacologia , Fatores de Transcrição , Regulação para Cima
8.
Int J Mol Sci ; 20(14)2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31336616

RESUMO

Reactive oxygen species (ROS) and free radicals are essential for transmission of cell signals and other physiological functions. However, excessive amounts of ROS can cause cellular imbalance in reduction-oxidation reactions and disrupt normal biological functions, leading to oxidative stress, a condition known to be responsible for the development of several diseases. The biphasic role of ROS in cellular functions has been a target of pharmacological research. Osteoclasts are derived from hematopoietic progenitors in the bone and are essential for skeletal growth and remodeling, for the maintenance of bone architecture throughout lifespan, and for calcium metabolism during bone homeostasis. ROS, including superoxide ion (O2-) and hydrogen peroxide (H2O2), are important components that regulate the differentiation of osteoclasts. Under normal physiological conditions, ROS produced by osteoclasts stimulate and facilitate resorption of bone tissue. Thus, elucidating the effects of ROS during osteoclast differentiation is important when studying diseases associated with bone resorption such as osteoporosis. This review examines the effect of ROS on osteoclast differentiation and the efficacy of novel chemical compounds with therapeutic potential for osteoclast related diseases.


Assuntos
Reabsorção Óssea/etiologia , Reabsorção Óssea/metabolismo , Diferenciação Celular , Osteoclastos/citologia , Osteoclastos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Biomarcadores , Remodelação Óssea/efeitos dos fármacos , Remodelação Óssea/genética , Reabsorção Óssea/tratamento farmacológico , Diferenciação Celular/efeitos dos fármacos , Humanos , Terapia de Alvo Molecular , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
9.
Eur J Microbiol Immunol (Bp) ; 8(1): 25-30, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29760962

RESUMO

The use of vancomycin for treatment of serious infections caused by MRSA strains has resulted in emergence of vancomycin-resistant Staphylococcus aureus (VRSA) in clinical settings. Following our previous report of phenotypic VRSA in Nigeria, the current study attempts to determine the genetic basis underlying this resistance. Over a period of 6 months, non-duplicate clinical S. aureus isolates from 73 consecutive patients with infective conditions at Ladoke Akintola University of Technology Teaching Hospital, Osogbo were tested against a panel of eight selected antibiotics by disk diffusion test. The Epsilom test strip was used to determine vancomycin minimum inhibitory concentration (MIC) and polymerase chain reaction (PCR) assay to amplify nuc, mecA, vanA, and vanB genes. Of 73 isolates, 61 (83.6%) had MIC of ≤2 µg/ml, 11 (15.1%) had 4-8 µg/ml and 1 (1.4%) had 16 µg/ml. The mecA gene was detected in 5 (6.8%) isolates but none contained vanA or vanB genes. Both vancomycin-susceptible and intermediate isolates were resistant to multiple antibiotics, while the only vancomycin resistant isolate was resistant to all eight antibiotics. The result confirms the occurrence of phenotypic vancomycin intermediate-resistant S. aureus (VISA) and VRSA infections in Nigeria, but the molecular basis will require further investigation.

10.
J Microbiol Immunol Infect ; 49(6): 992-995, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25655992

RESUMO

This longitudinal study on Staphylococcus aureus colonization in Nigerian human immunodeficiency virus patients (n = 187) found a trend towards a higher proportion of persistent S. aureus carriage in patients with advanced human immunodeficiency virus infection, low CD4+ cell counts, and a predominance of isolates belonging to ST8/spa-CC064 in persistent carriers.


Assuntos
Antirretrovirais/uso terapêutico , Portador Sadio/microbiologia , Infecções por HIV/virologia , Mucosa Nasal/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/crescimento & desenvolvimento , Adulto , Contagem de Linfócito CD4 , Feminino , Humanos , Estudos Longitudinais , Masculino , Tipagem de Sequências Multilocus , Nigéria , Fatores de Risco , Staphylococcus aureus/classificação , Staphylococcus aureus/isolamento & purificação
11.
Inhal Toxicol ; 27(14): 778-86, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26671196

RESUMO

A non-cancer inhalation chronic toxicity assessment for diethylamine (DEA, CAS number 109-89-7) was conducted by the Texas Commission on Environmental Quality. A chronic Reference Value (ReV) was determined based on a high-quality study conducted in mice and rats by the National Toxicology Program. Chronic inhalation ReVs are health-based exposure concentrations used in assessing health risks of long-term (i.e. lifetime) chemical exposure. DEA is used industrially as an organic intermediate to produce corrosion inhibitors, and is widely used in rubber, pharmaceuticals, resins, pesticides, insect repellants, dye processing and as a polymerization inhibitor. Although systemic effects have been noted at higher concentrations, DEA acts primarily as a respiratory irritant with effects occurring in the upper respiratory tract. Rats were exposed to 0, 31, 62.5 and 125 ppm DEA and mice to 0, 16, 31 and 62.5 ppm DEA for 6 h/day, 5 days/week for 105 weeks. Mice were slightly more sensitive than rats. The critical effect identified in mice was hyperostosis in the turbinates although DEA caused a number of other non-neoplatic lesions. Dose-response data were suitable to benchmark concentration (BMC) modeling. The human equivalent point of departure (PODHEC) was calculated from the 95% lower limit of the BMC(10) using default duration and animal-to-human dosimetric adjustments. Total uncertainty factors of 90 were applied to the PODHEC to account for variation in sensitivity within the human population, toxicodynamic differences between mice and humans, and database uncertainty. The chronic ReV for DEA is 11 ppb (33 µg/m(3)).


Assuntos
Dietilaminas/toxicidade , Doenças Respiratórias/induzido quimicamente , Administração por Inalação , Animais , Dietilaminas/administração & dosagem , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Masculino , Camundongos , Ratos , Doenças Respiratórias/patologia , Testes de Toxicidade/métodos
12.
J Environ Public Health ; 2015: 401340, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26064140

RESUMO

The management of genitourinary candidiasis (GC) is fraught with challenges, especially, in an era of increasing antifungal resistance. This descriptive cross-sectional study conducted between May 2013 and January 2014 determined the prevalence and characteristics of GC and the species of Candida among 369 attendees of a Sexually Transmitted Disease (STD) clinic of Ladoke Akintola University Teaching Hospital, Osogbo, Nigeria. Appropriate urogenital specimen collected from each attendee was examined by microscopy and culture for Candida, with preliminary species identification by CHROMAgar Candida and confirmation by Analytical Profile Index (API) 20C AUX. The age range of attendees was 1-80 years, mean age was 36.32 ± 11.34 years, and male to female ratio was 1 to 3. The prevalence of genitourinary candidiasis was 47.4%, with 4.9% in males and 42.5% in females (p < 0.0001). The age groups 31-45 and 16-30 have the highest prevalence of 23.3% and 16.8%, respectively. The species of Candida recovered include Candida glabrata 46.9%, Candida albicans 33.7%, Candida dubliniensis 9.7%, Candida tropicalis 5.7%, Candida krusei 1.7%, Candida lusitaniae 1.7%, and Candida utilis 0.6%. This study reported non-C. albicans Candida, especially C. glabrata, as the most frequently isolated species in GC, contrary to previous studies in this environment and elsewhere.


Assuntos
Candida/isolamento & purificação , Candidíase/epidemiologia , Doenças Urogenitais Femininas/epidemiologia , Doenças Urogenitais Masculinas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Instituições de Assistência Ambulatorial/estatística & dados numéricos , Candida/classificação , Candidíase/microbiologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Doenças Urogenitais Femininas/microbiologia , Hospitais de Ensino , Humanos , Lactente , Recém-Nascido , Masculino , Doenças Urogenitais Masculinas/microbiologia , Pessoa de Meia-Idade , Nigéria/epidemiologia , Prevalência , Adulto Jovem
13.
Infect Drug Resist ; 6: 87-92, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23990730

RESUMO

INTRODUCTION: The characteristics and antimicrobial resistance profiles of Staphylococcus aureus differs according to geographical regions and in relation to antibiotic usage. The aim of this study was to determine the biochemical characteristics of the prevalent S. aureus from Ekiti State, Nigeria, and to evaluate three commonly used disk diffusion methods (cefoxitin, oxacillin, and methicillin) for the detection of methicillin resistance in comparison with mecA gene detection by polymerase chain reaction. MATERIALS AND METHODS: A total of 208 isolates of S. aureus recovered from clinical specimens were included in this study. Standard microbiological procedures were employed in isolating the strains. Susceptibility of each isolate to methicillin (5 µg), oxacillin (1 µg), and cefoxitin (30 µg) was carried out using the modified Kirby-Bauer/Clinical and Laboratory Standard Institute disk diffusion technique. They were also tested against panels of antibiotics including vancomycin. The conventional polymerase chain reaction method was used to detect the presence of the mecA gene. RESULTS: Phenotypic resistance to methicillin, oxacillin, and cefoxitin were 32.7%, 40.3%, and 46.5%, respectively. The mecA gene was detected in 40 isolates, giving a methicillin-resistant S. aureus (MRSA) prevalence of 19.2%. The S. aureus isolates were resistant to penicillin (82.7%) and tetracycline (65.4%), but largely susceptible to erythromycin (78.8% sensitive), pefloxacin (82.7%), and gentamicin (88.5%). When compared to the mecA gene as the gold standard for MRSA detection, methicillin, oxacillin, and cefoxitin gave sensitivity rates of 70%, 80%, and 100%, and specificity rates of 76.2%, 69.1%, and 78.5% respectively. CONCLUSION: When compared with previous studies employing mecA polymerase chain reaction for MRSA detection, the prevalence of 19.2% reported in Ekiti State, Nigeria in this study is an indication of gradual rise in the prevalence of MRSA in Nigeria. A cefoxitin (30 µg) disk diffusion test is recommended above methicillin and oxacillin for the phenotypic detection of MRSA in clinical laboratories.

14.
BMC Infect Dis ; 12: 286, 2012 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-23121720

RESUMO

BACKGROUND: The staphylococci are implicated in a variety of human infections; however, many clinical microbiology laboratories in Nigeria do not identify staphylococci (in particular coagulase negative staphylococci - CNS) to the species level. Moreover, data from multi-centre assessment on antibiotic resistance and epidemiology of the staphylococci are not available in Nigeria. This study investigated 91 non-duplicate staphylococcal isolates obtained from the microbiology laboratories of eight hospitals in Nigeria during the period January to April 2010. METHODS: Identification and antibiotic susceptibility testing was performed using the VITEK 2 system, detection of resistance genes by PCR, and molecular characterization was determined by SCCmec typing, spa and multilocus sequence typing (MLST). RESULTS: All the isolates were susceptible to mupirocin, tigecycline, vancomycin and linezolid, but 72.5% of CNS and 82.3% of Staphylococcus aureus were resistant to cotrimoxazole, while multiresistance was observed in 37 of the 40 CNS isolates. Untypeable SCCmec types (ccrC/Class A mec and ccr-negative/Class C2 mec gene complex) in two methicillin-resistant S. aureus (MRSA) were identified. Additionally, ccr-negative/Class A mec and ccr type 4/Class C2 mec gene complex was detected in one isolate each of S. sciuri and S. haemolyticus, respectively. The S. aureus isolates were classified into 21 spa types including two new types (t8987, t9008) among the methicillin-susceptible S. aureus (MSSA) isolates. Two (CC8-SCCmecnon-typeable and CC88-SCCmec IV) and four (CC8-SCCmec III/IV/V; CC30-SCCmec II/III; CC88-SCCmec IV; and ST152-SCCmecnon-typeable) MRSA clones were identified in Maiduguri (North-East Nigeria) and South-West Nigeria, respectively. The proportion of Panton-Valentine leukocidin (PVL)-positive MSSA was high (44.4%) and 56.3% of these strains were associated with sequence type (ST) 152. CONCLUSIONS: The identification of multiresistant mecA positive S. haemolyticus and S. sciuri from clinical samples indicates that characterization of CNS is important in providing information on their diversity and importance in Nigeria. There is the need to develop new SCCmec classification methods for non-typeable methicillin-resistant staphylococci, and to curtail the spread and establishment of the S. aureus ST152 clone in Nigeria. The study presents the first report of a PVL-positive ST152-SCCmecnontypeable MRSA and SCCmec typing of methicillin-resistant CNS in Nigeria.


Assuntos
Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/classificação , Staphylococcus/efeitos dos fármacos , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Hospitais , Humanos , Resistência a Meticilina , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem Molecular , Nigéria/epidemiologia , Staphylococcus/isolamento & purificação
15.
Afr J Infect Dis ; 5(2): 40-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-23878706

RESUMO

Enterococci are opportunistic bacteria that become pathogenic when they colonize niches where they are not normally found. Of recent, they have become major cause of nosocomial infections, especially of the bloodstream, urinary tract and surgical sites. The aim of this study is to determine the point-prevalence rate of human enterococci infections among hospitalized patients in Osogbo, Nigeria. The study was conducted between January and June 2009 in two primary-care hospitals in Osogbo and involved a total of 118 patients who developed clinical evidence of infection at least 48 hours after hospital admission. Appropriate clinical samples were collected from the patients after an informed consent and cultured for isolation/biochemical identification of Enterococcus species at the Bacteriology Laboratory of Ladoke Akintola University of Technology, Osogbo using standard microbiological methods. There were 525 hospital admissions within the time frame of the study of which 118 (22.5%) developed hospital acquired infection (HAI); 58 (49.2%) of which cultured positive for bacterial pathogens. Enterococci were isolated from infective focus in 7 patients, giving a prevalence rate of hospital-acquired enterococci infection of 5.9%. Two species of Enterococcus were identified; Enterococcus faecalis from urinary tract infection (UTI) and surgical site infection (SSI) of 6 (85.7%) patients and Enterococcus faecium from UTI in 1 (14.3%) patient. Other bacteria recovered from other infective foci were Klebsiella spp 31.0%, Pseudomonas spp 20.7%, Staphylococcus aureus 17.2%, Escherichia coli 12.1%, Staphylococcus epidermidis 3.4%, Streptococcus pneumoniae 1.7% and Serratia spp 1.7%. All the enterococci isolates were multiply antibiotic resistant, and 42.9% were vancomycin-resistant enterococci (VRE) with the VRE strains showing resistance to wider range of antibiotics than the vancomycin-sensitive strains. Other Gram-positive and Gram negative bacterial isolates also demonstrated multiple resistance to all commonly available antibiotics in this community except E. coli and Pseudomonas spp which were relatively sensitive to ciprofloxacin and ceftazidime. This limited study demonstrated a high prevalence rate of multiple antibiotic resistant enterococci infections among hospitalized patients in this environment. There is need for systematic surveillance of hospitals for enterococci infections; prudent use and rational prescription of antibiotics and stringent measures to reduce the prevalence rate by health education on infection control measures such as isolation, cleaning, disinfection and sterilization.

16.
Afr. j. infect. dis. (Online) ; 5(2): 40-46, 2011. tab
Artigo em Inglês | AIM (África) | ID: biblio-1257252

RESUMO

Enterococci are opportunistic bacteria that become pathogenic when they colonize niches where they are not normally found. Of recent; they have become major cause of nosocomial infections; especially of the bloodstream; urinary tract and surgical sites. The aim of this study is to determine the point-prevalence rate of human enterococci infections among hospitalized patients in Osogbo; Nigeria. The study was conducted between January and June 2009 in two primary-care hospitals in Osogbo and involved a total of 118 patients who developed clinical evidence of infection at least 48 hours after hospital admission. Appropriate clinical samples were collected from the patients after an informed consent and cultured for isolation/biochemical identification of Enterococcus species at the Bacteriology Laboratory of Ladoke Akintola University of Technology; Osogbo using standard microbiological methods. There were 525 hospital admissions within the time frame of the study of which 118 (22.5) developed hospital acquired infection (HAI); 58 (49.2) of which cultured positive for bacterial pathogens. Enterococci were isolated from infective focus in 7 patients; giving a prevalence rate of hospital-acquired enterococci infection of 5.9. Two species of Enterococcus were identified; Enterococcus faecalis from urinary tract infection (UTI) and surgical site infection (SSI) of 6 (85.7) patients and Enterococcus faecium from UTI in 1 (14.3) patient. Other bacteria recovered from other infective foci were Klebsiella spp 31.0; Pseudomonas spp 20.7; Staphylococcus aureus 17.2; Escherichia coli 12.1; Staphylococcus epidermidis 3.4; Streptococcus pneumoniae 1.7and Serratia spp 1.7. All the enterococci isolates were multiply antibiotic resistant; and 42.9were vancomycin-resistant enterococci (VRE) with the VRE strains showing resistance to wider range of antibiotics than the vancomycin-sensitive strains. Other Gram-positive and Gram negative bacterial isolates also demonstrated multiple resistance to all commonly available antibiotics in this community except E. coli and Pseudomonas spp which were relatively sensitive to ciprofloxacin and ceftazidime. This limited study demonstrated a high prevalence rate of multiple antibiotic resistant enterococci infections among hospitalized patients in this environment. There is need for systematic surveillance of hospitals for enterococci infections; prudent use and rational prescription of antibiotics and stringent measures to reduce the prevalence rate by health education on infection control measures such as isolation; cleaning; disinfection and sterilization


Assuntos
Infecção Hospitalar , Enterococcus , Hospitais , Nigéria , Prevalência , Atenção Primária à Saúde
17.
Sex Transm Infect ; 83(5): 357-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17493980

RESUMO

OBJECTIVE: To determine the seroprevalence rate of syphilis among pregnant women attending the antenatal clinics of a teaching and a state specialist hospital in Nigeria, in order to ascertain whether maternal screening should be incorporated into routine antenatal care of our hospitals. METHODS: A screening for syphilis for 505 newly registered pregnant women was carried out using the qualitative rapid plasma reagin (RPR) test. All reactive sera were then subjected to the quantitative RPR test to estimate the titre of each sample. The Treponema pallidum haemagglutination antibody (TPHA) test was used as confirmatory test of all positive RPR sera. RESULTS: A total of 50 women (9.9%) were positive for RPR; 15 (2.97%) were positive for TPHA, giving a seroprevalence rate of 2.97%. A total of 32 women (6.34%) were RPR positive at 1:2, 7 (1.39%) at 1:4 and 11 (2.2%) at 1:8. Of the women positive for RPR at 1:2, 2 were also TPHA positive, 2 of the 7 positive at 1:4 were TPHA positive, while all 11 positive women at 1:8 were TPHA positive. In all, 70% of all RPR positive women screened were biological false positives. Eleven of the 15 women had high titre active syphilis (RPR > or = 1:8, TPHA+) while 4 had low titre active syphilis (RPR <1:8, TPHA+). CONCLUSIONS: The 2.97% seroprevalence rate obtained after accounting for biological false positives was considered high. Screening for syphilis in pregnancy should be incorporated into routine antenatal practice in Nigerian hospitals.


Assuntos
Complicações Infecciosas na Gravidez/diagnóstico , Diagnóstico Pré-Natal/métodos , Sífilis/diagnóstico , Adulto , Anticorpos Antibacterianos/sangue , Feminino , Testes de Hemaglutinação , Humanos , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Nigéria/epidemiologia , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Diagnóstico Pré-Natal/estatística & dados numéricos , Prevalência , Sífilis/epidemiologia , Treponema pallidum/isolamento & purificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...