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1.
PLoS One ; 15(9): e0238390, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32886694

RESUMEN

Pseudomonas aeruginosa has been implicated in a wide range of post-operation wound and lung infections. A wide range of acquired resistance and virulence markers indicate surviving strategy of P. aeruginosa. Complete-genome analysis has been identified as efficient approach towards understanding the pathogenicity of this organism. This study was designed to sequence the entire genome of P. aeruginosa UY1PSABAL and UY1PSABAL2; determine drug-resistance profiles and virulence factors of the isolates; assess factors that contribute toward stability of the genomes; and thereafter determine evolutionary relationships between the strains and other isolates from similar sources. The genomes of the MDR P. aeruginosa UY1PSABAL and UY1PSABAL2 were sequenced on the Illumina Miseq platform. The raw sequenced reads were assessed for quality using FastQC v.0.11.5 and filtered for low quality reads and adapter regions using Trimmomatic v.0.36. The de novo genome assembly was made with SPAdes v.3.13 and annotated using Prokka v.2.1.1 annotation pipeline; Rapid Annotation using Subsytems Technology (RAST) server v.2.0; and PATRIC annotation tool v.3.6.2. Antimicrobial resistance genes and virulence determinants were searched through the functional annotation data generated from Prokka, RAST and PATRIC annotation pipelines; In addition to ResFinder and Comprehensive Antibiotic Resistance Database (CARD) which were employed to determine resistance genes. The PHAge Search Tool Enhanced Release (PHASTER) web server was used for the rapid identification and annotation of prophage sequences within bacterial genome. Predictive secondary metabolites were identified with AntiSMASH v.5.0. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and cas genes regions were also investigated with the CRISPRone and CRISPRFinder server. The genome sizes of 7.0 and 6.4 Mb were determined for UY1PSABAL and UY1PSABAL2 strains with G+C contents of 66.1% and 66.48% respectively. ß-lactamines resistance genes blaPAO, aminoglycoside phosphorylating enzymes genes aph(3')-IIb, fosfomycine resistance gene fosA, vancomycin vanW and tetracycline tetA were among identified resistance genes harboured in both isolates. UY1PSABAL bore additional aph(6)-Id, aph(3'')-Ib, ciprofloxacin-modifying enzyme crpP and ribosomal methylation enzyme rmtB. Both isolates were found harbouring virulence markers such as flagella and type IV pili; and also present various type III secretion systems such as exoA, exoS, exoU, exoT. Secondary metabolites such as pyochelin and pyoverdine with iron uptake activity were found within the genomes as well as quorum-sensing systems, and various fragments for prophages and insertion sequences. Only the UY1PSABAL2 contains CRISPR-Cas system. The phylogeny revealed a very close evolutionary relationship between UY1PSABAL and the similar strain isolated from Malaysia; the same trend was observed between UY1PSABAL2 and the strain from Chinese origin. Complete analyses of the entire genomes provide a wide range of information towards understanding pathogenicity of the pathogens in question.


Asunto(s)
Resistencia a Múltiples Medicamentos/genética , Pseudomonas aeruginosa/genética , Composición de Base , Camerún , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Genoma Bacteriano/genética , Humanos , Filogenia , Profagos/genética , Pseudomonas aeruginosa/aislamiento & purificación , Análisis de Secuencia de ADN , Virulencia/genética , Secuenciación Completa del Genoma/métodos
2.
Microorganisms ; 8(5)2020 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-32403300

RESUMEN

BACKGROUND: Pseudomonas aeruginosa (PSA) and Acinetobacter baumannii (ACB) are non-fermentative bacteria mostly associated with nosocomial infections in humans. OBJECTIVE: This study aimed to determine the antimicrobial resistance profiles and virulence gene of PSA and ACB previously isolated from humans in selected health facilities in Yaoundé, Cameroon. METHODS: A total of 77 and 27 presumptive PSA and ACB isolates, respectively, were collected from the Yaoundé teaching hospital. These isolates were previously isolated from various samples including pus, blood and broncho-alveolar lavage. The identities of the isolates were determined through polymerase chain reaction (PCR) amplification of PSA and ACB specific sequences. Antimicrobial susceptibility testing (AST) was performed using the Kirby-Bauer disc diffusion method. Phenotypical expression of AmpC ß-lactamases (AmpC), extended spectrum ß-lactamases (ESBLs) and metallo ß-Lactamases (MBLs) were determined using the combined disc method. Bacterial genomes were screened for the presence of ß-lactamases blaTEM and blaCTXM genes using specific PCR. The pathogenicity of PSA and ACB was assessed through amplification of the lasB, exoA, pslA and exoS as well as OmpA and csuE virulence genes, respectively. RESULTS: Of the 77 presumptive PSA isolates, a large proportion (75 to 97.4%) were positively identified. All (100%) of the presumptive 27 ACB harbored the ACB-specific ITS gene fragment by PCR. Twenty five percent of the PSA isolates produced ESBLs phenotypically while more than 90% of these isolates were positive for the lasB, exoA, pslA and exoS genes. A large proportion (88%) of the ACB isolates harboured the OmpA and csuE genes. blaTEM and blaCTXM were detected in 17 and 4% of PSA, respectively, while a much higher proportion (70 and 29%) of the ACB isolates possessed these resistance determinants respectively. CONCLUSION: Our findings reveal the occurrence of both virulence and drug-resistant determinants in clinical PSA and ACB isolates from patients in health care settings in Yaoundé, Cameroon, thus suggesting their role in the pathological conditions in patients.

3.
Appl Clin Genet ; 12: 229-234, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31819589

RESUMEN

Background and objectives: The association of chemokine receptor-2 (CCR2) polymorphism with HIV transmission or disease progression remains highly controversial. The role of CCR2-64I allele in HIV infection may differ from one population to another because of their genetic background. The objectives of this study were to characterize the CCR2 genetic polymorphism and to determine its potential effect in HIV acquisition in children living in the Northern Region of Cameroon. Materials and methods: A cross-sectional study was carried out in five health facilities in the Northern region of Cameroon. DNA was extracted from the Buffy coat of each participant using the QIAamp®DNA mini kit. The DNA extract was then subjected to polymorphic analyses. CCR2 genotypes were analyzed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). The Chi-Squared test was used for the assessment of the Hardy-Weinberg equilibrium. Results: A total of 134 children under 15 years comprised of 38 HIV-exposed infected (28.36%) and 96 HIV-exposed un-infected (71.64%) participants were recruited. Prevalences of 44.78% wild type homozygous, 48.52% heterozygous and 6.7% mutant homozygous alleles were found in the overall population. An allelic frequency of 29.69% for the mutant allele CCR2-64I was found in HIV-exposed un-infected individuals as compared to 34.21% in HIV-infected children (p=0.47). Conclusion: The CCR2-64I allele is relatively common in the Northern Region of Cameroon, with a similar distribution among HIV-exposed un-infected and infected children. As this allele alone does not seem to confer protection against HIV-1 infection, further studies using genotype-combination of CCR2 polymorphism and other single nucleotide polymorphisms would be of great relevance in both HIV prevention and novel therapeutic strategies.

4.
Methods Mol Biol ; 2013: 29-44, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31267491

RESUMEN

Malaria infection is one of the major causes of deaths in the African continent. The high burden of malaria in Africa is due to P. falciparum, which adapts and cospecializes with Anopheles gambiae, the most effective and widespread malaria vector. Since 2000, the incidence of malaria has been reduced by 17% and malaria mortality rates by 26%. However, the rate of decline has stalled and even reversed in some regions since 2014. In 2017 as described by the latest World malaria report, 219 million malaria cases were reported, up from 2017 million cases reported in 2016 in 91 countries, and the global tally of malaria deaths reached 435,000 deaths, compared with 451,000 estimated deaths in 2016. Despite these achievements, the African region continues to account for about 92% of malaria cases and deaths worldwide. Therefore, it is important to master the current situation of malaria in Africa to see how to better plan its elimination. In this chapter, we present the current situation and prospective means to improve it, including a salutogenesis approach.


Asunto(s)
Malaria/epidemiología , Malaria/prevención & control , África/epidemiología , Animales , Anopheles/parasitología , Humanos , Mosquitos Vectores/parasitología
5.
Methods Mol Biol ; 2013: 73-82, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31267494

RESUMEN

Diagnosing malaria is a key component of effective case management and monitoring of antimalarial programs worldwide. This chapter features the different diagnostic approaches currently in use or under testing for use in case management and/or epidemiological studies of malaria. Emphasis is laid on the basic principles of each diagnostic approach as well as their operational limits under different malaria endemicity settings. The discussed methods are defined as "conventional" or "unconventional" depending on their widespread use in malaria case management. The chapter therefore provides a practical guide to students, health practitioners, and field researchers involved in the fight against malaria through community-based interventions.


Asunto(s)
Malaria/diagnóstico , Antimaláricos , Humanos , Malaria/prevención & control
6.
Vector Borne Zoonotic Dis ; 19(7): 455-465, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30985268

RESUMEN

Nipah virus (NiV) and Hendra virus (HeV) are closely related members within the genus Henipavirus, family Paramyxoviridae, for which fruit bats serve as the reservoir. The initial emergence of NiV infections in pigs and humans in Malaysia, and HeV infections in horses and humans in Australia, posed severe impacts on human and animal health, and continues threatening lives of humans and livestock within Southeast Asia and Australia. Recently, henipavirus-specific antibodies have also been detected in fruit bats in a number of sub-Saharan African countries and in Brazil, thereby considerably increasing the known geographic distribution of henipaviruses. Africa is progressively being recognized as a new high prevalence zone for henipaviruses, as deduced from serological and molecular evidence of past infections in Madagascar, Ghana, Republic of Congo, Gulf of Guinea, Zambia, Tanzania, Cameroon, and Nigeria lately. Serological data suggest henipavirus spillover from bats to livestock and human populations in Africa without reported clinical disease in any of these species. All virus isolation attempts have been abortive, highlighting the need for further investigations. The genome of the Ghanaian bat henipavirus designated Ghana virus (GhV), which was detected in a pteropid Eidolon helvum bat, is the only African henipavirus that has been completely sequenced limiting our current knowledge on the genetic diversity and pathogenesis of African henipaviruses. In this review, we summarize the available data on the circulation of henipaviruses in Africa, discuss potential sources for virus spillover, and highlight existing research gaps.


Asunto(s)
Quirópteros/virología , Infecciones por Henipavirus/epidemiología , Henipavirus , África/epidemiología , Animales , Anticuerpos Antivirales , Infecciones por Henipavirus/veterinaria , Infecciones por Henipavirus/virología , Humanos , Ganado/virología , Estudios Seroepidemiológicos , Zoonosis/virología
7.
BMC Pulm Med ; 19(1): 17, 2019 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-30654769

RESUMEN

BACKGROUND: Extra-pulmonary tuberculosis (EPTB) is defined as any bacteriologically confirmed or clinically diagnosed case of TB involving organs other than the lungs. It is frequently a diagnostic and therapeutic challenge with paucity of data available. The aim of this study was to assess the prevalence of bacteriologically confirmed EPTB; to determine the most affected organs and to evaluate the therapeutic outcome of EPTB patients treated under program conditions in the littoral region of Cameroon. METHODS: A descriptive cross-sectional laboratory-based epidemiological survey was conducted from January 2016 to December 2017 and 109 specimens from 15 of the 39 diagnosis and treatment centers in the littoral region were obtained. Two diagnostic methods (Gene Xpert MTB and culture (LJ and MGIT) were used for EPTB diagnosis. Determine HIV1/2 and SD Biolinewere used for HIV diagnosis. Confirmed EPTB cases were treated following the national tuberculosis guide. RESULTS: The prevalence of bacteriologically confirmed EPTB was 41.3% (45). All 45 cases were sensitive to rifampicin. Males were predominately more infected [26 (57.8%)] likewise the age group 31-45 years with 15 (33.3%) cases. The overall prevalence for HIV was 33.6% (36). HIV infection was present in 28.9% (13) of patients with EPTB. The most affected sites with EPTB were: Lymph nodes (66.5%), pleural cavity (15.6%), abdominal organs (11.1%), neuromeningeal (2.2%), joints (2.2%) and heart (2.2%). Overall, 84.4% of the study participants had a therapeutic success with males responding better 57.9% (p = 0.442). Therapeutic success was better (71.7%) in HIV negative EPTB patients (p = 0.787). CONCLUSION: The prevalence of bacteriologically confirmed EPTB patients treated under program conditions in the littoral region of Cameroon is high with a therapeutic success of 84.4% and the lymph nodes is the most affected site.


Asunto(s)
Infecciones por VIH/epidemiología , Tuberculosis/epidemiología , Adolescente , Adulto , Antituberculosos/uso terapéutico , Camerún/epidemiología , Coinfección/epidemiología , Estudios Transversales , Farmacorresistencia Bacteriana , Femenino , Humanos , Masculino , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular , Prevalencia , Rifampin/uso terapéutico , Factores Sexuales , Resultado del Tratamiento , Tuberculosis/tratamiento farmacológico , Tuberculosis Cardiovascular/tratamiento farmacológico , Tuberculosis Cardiovascular/epidemiología , Tuberculosis del Sistema Nervioso Central/tratamiento farmacológico , Tuberculosis del Sistema Nervioso Central/epidemiología , Tuberculosis Ganglionar/tratamiento farmacológico , Tuberculosis Ganglionar/epidemiología , Tuberculosis Osteoarticular/tratamiento farmacológico , Tuberculosis Osteoarticular/epidemiología , Tuberculosis Pleural/tratamiento farmacológico , Tuberculosis Pleural/epidemiología , Adulto Joven
8.
BMC Res Notes ; 11(1): 723, 2018 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-30309385

RESUMEN

OBJECTIVES: Disruption in HIV care provision may enhance the development and spread of drug resistance due to inadequate antiretroviral therapy. This study thus determined the prevalence of HIV-1 transmitted drug resistance (TDR) in settings of decentralized therapy and care in Senegal and, the Ebola outbreak in Guinea. Antiretroviral-naïve patients were enrolled following a modified WHO TDR Threshold Survey method, implemented in Senegal (January-March 2015) and Guinea (August-September 2015). Plasma and dried blood spots specimens, respectively from Senegalese (n = 69) and Guinean (n = 50) patients, were collected for direct sequencing of HIV-1 pol genes. The Stanford Calibrated Population Resistance program v6.0 was used for Surveillance Drug Resistance Mutations (SDRMs). RESULTS: Genotyping was successful from 54/69 (78.2%) and 31/50 (62.0%) isolates. In Senegal, TDR prevalence was 0% (mean duration since HIV diagnosis 4.08 ± 3.53 years). In Guinea, two patients exhibited SDRMs M184V (NRTI), T215F (TAM) and, G190A (NNRTI), respectively. TDR prevalence at this second site, however, could not be ascertained because of low sample size. Phylogenetic inference confirmed CRF02_AG predominance in Senegal (62.96%) and Guinea (77.42%). TDR prevalence in Senegal remains extremely low suggesting improved control measures. Continuous surveillance in both settings is mandatory and, should be done closest to diagnosis/transmission time and with larger sample size.


Asunto(s)
Fármacos Anti-VIH/provisión & distribución , Brotes de Enfermedades , Farmacorresistencia Viral/genética , Infecciones por VIH/epidemiología , VIH-1/genética , Fiebre Hemorrágica Ebola/epidemiología , Adulto , Ebolavirus/patogenicidad , Femenino , Técnicas de Genotipaje , Guinea/epidemiología , Infecciones por VIH/transmisión , VIH-1/clasificación , VIH-1/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Mutación , Filogenia , Vigilancia en Salud Pública/métodos , Senegal/epidemiología
9.
PLoS Negl Trop Dis ; 12(7): e0006572, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29965961

RESUMEN

BACKGROUND: The environmental pathogen, Mycobacterium ulcerans (MU) can infect both humans and animals and cause Buruli ulcer (BU) disease. However, its mode(s) of transmission from the colonized environment to human/animal hosts remain unclear. In Australia, MU can infect both wildlife and domestic mammals. Till date, BU-like lesions have only been reported in wildlife in Africa. This warrants a thorough assessment of possible MU in domestic animals in Africa. Here, we screened roaming domesticated animals that share the human microhabitat in two different BU endemic sites, Sedje-Denou in Benin and Akonolinga in Cameroon, for MU lesions. METHODOLOGY/PRINCIPAL FINDINGS: We screened roaming mammals and birds across 3 endemic villages of Sedje-Denou in Southern Benin and 6 endemic villages of Akonolinga in Cameroon. After approval from relevant authorities, specimens (wound swabs and tissue fragments) were collected from animals with open or active lesion and systematically screened to detect the presence of MU though the diagnostic DNA targets IS2404, IS2606 and KR-B. Out of 397 animals surveyed in Akonolinga, 44 (11.08%) carried skin lesions and all were negative for MU DNA. For Sedje-Denou, only 25 (6.93%) out of 361 animals surveyed carried external skin lesions of which 2 (8%) were positive for MU DNA targets. These MU infected lesions were found in two different villages on a goat (abdominal part) and on a dog (nape area of the neck). Source-tracking of MU isolates within infected animal lesions was performed using VNTR genotyping and further confirmed with sequencing. One MU VNTR genotype (Z) was successfully typed from the goat lesion. The evolutionary history inferred from sequenced data revealed a clustering of animal MU isolates within isolates from human lesions. CONCLUSION/SIGNIFICANCE: This study describes the first report of two MU infected lesions in domestic animals in Africa. Their DNA sequence analyses show close relationship to isolates from human cases. It suggests that MU infection should be suspected in domestic hosts and these could play a role in transmission. The findings further support the hypothesis that MU is a ubiquitous environmental pathogen found in endemic areas, and probably involved in a multiple transmission pathway.


Asunto(s)
Animales Domésticos/microbiología , Úlcera de Buruli/transmisión , Úlcera de Buruli/veterinaria , Mycobacterium ulcerans/aislamiento & purificación , Zoonosis/transmisión , Animales , Benin , Úlcera de Buruli/microbiología , Camerún , Pollos , Enfermedades de los Perros/microbiología , Perros , Patos , Femenino , Genotipo , Enfermedades de las Cabras/microbiología , Cabras , Humanos , Masculino , Mycobacterium ulcerans/clasificación , Mycobacterium ulcerans/genética , Mycobacterium ulcerans/fisiología , Filogenia , Enfermedades de las Aves de Corral/microbiología , Ovinos , Enfermedades de las Ovejas/microbiología , Zoonosis/microbiología
10.
BMC Med Genet ; 19(1): 78, 2018 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-29751826

RESUMEN

BACKGROUND: The association between ABCC8 gene C49620T polymorphism and type 2 diabetes (T2D) in populations of diverse ethnic backgrounds has been reported. However, such occurrence in an African population is yet to be established. This case-control study involving 73 T2D and 75 non-diabetic (ND) patients investigated the occurrence of this polymorphism among T2D patients in Nigeria and assessed its relationship with body lipids of patients. METHODS: Demographic and clinical characteristics of patients were collected and lipid profile indices including total cholesterol (TC), triglyceride (TG), low density lipoprotein (LDL) and high density lipoprotein (HDL) were assayed. Restriction fragment length polymorphism-PCR (RFLP-PCR) was employed to genotype the ABCC8-C49620T polymorphism using PstI restriction enzyme. RESULTS: This study revealed significantly (p < 0.05) higher prevalence of the T allele of the ABCC8 gene in T2D patients (33.1%) compared to ND patients (28.0%). The mutant TT genotype was also higher than the CC and CT genotypes in T2D patients compared to ND patients but did not show any significant risk (p>0.05) of T2D for the unadjusted codominant, dominant and recessive models. Following age adjustment, the mutant genotypes (CT and TT) showed significant (p<0.05) risk of T2D for all the models with the recessive model presenting the greatest risk of T2D (OR: 2.39, 95% CI: 1.16-4.91, p<0.018). The TT genotype significantly (p<0.05) associated with high level of HDL and reduced levels of TC, TG and LDL in non-diabetic patients but was not associated with any of the demographic and clinical characteristics among T2D patients. CONCLUSIONS: ABCC8 C49620T polymorphism showed possible association with T2D marked by predominance of the mutant TT genotype in T2D patients. However, the relationship between TT genotype and lipid abnormalities for possible beneficial effect on people suffering from T2D is unclear.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Estudios de Asociación Genética/métodos , Mutación Puntual , Receptores de Sulfonilurea/genética , Grupo de Ascendencia Continental Africana/genética , Alelos , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Persona de Mediana Edad , Nigeria
11.
BMC Complement Altern Med ; 18(1): 86, 2018 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-29530027

RESUMEN

BACKGROUND: Khaya grandifoliola (C.D.C.) stem bark, Cymbopogon citratus (Stapf) and Cryptolepis sanguinolenta (Lindl.) Schltr leaves are used in Cameroonian traditional medicine for the treatment of inflammatory diseases. Several studies have been performed on the biological activities of secondary metabolites extracted from these plants. However, to the best of our knowledge, the anti-neuro inflammatory and protective roles of the polysaccharides of these three plants have not yet been elucidated. This study aimed at investigating potential use of K. grandifoliola, C. sanguinolenta and C. citratus polysaccharides in the prevention of chronic inflammation. METHODS: Firstly, the composition of polysaccharide fractions isolated from K. grandifoliola stem bark (KGF), C. sanguinolenta (CSF) and C. citratus (CCF) leaves was assessed. Secondly, the cytotoxicity was evaluated on Raw 264.7 macrophages and U87-MG glioblastoma cell lines by the MTT assay. This was followed by the in vitro evaluation of the ability of KGF, CSF and CCF to inhibit lipopolysaccharides (LPS) induced overproduction of various pro-inflammatory mediators (NO, ROS and IL1ß, TNFα, IL6, NF-kB cytokines). This was done in Raw 264.7 and U87-MG cells. Finally, the in vitro protective effect of KGF, CSF and CCF against LPS-induced toxicity in the U87-MG cells was evaluated. RESULTS: CCF was shown to mostly contain sugar and no polyphenol while KGP and CSP contained very few amounts of these metabolites (≤ 2%). The three polysaccharide fractions were non-toxic up to 100 µg.mL- 1. All the polysaccharides at 10 µg/mL inhibited NO production, but only KGF and CCF at 12.5 µg/mL down-regulated LPS-induced ROS overproduction. Finally, 100 µg/mL LPS reduced 50% of U87 cell viability, and pre-treatment with the three polysaccharides significantly increased the proliferation. CONCLUSION: These results suggest that the polysaccharides of K. grandifoliola, C. citratus and C. sanguinolenta could be beneficial in preventing/treating neurodegenerative diseases in which neuroinflammation is part of the pathophysiology.


Asunto(s)
Cryptolepis/química , Cymbopogon/química , Glioblastoma/tratamiento farmacológico , Macrófagos/efectos de los fármacos , Meliaceae/química , Enfermedades Neurodegenerativas/tratamiento farmacológico , Extractos Vegetales/farmacología , Polisacáridos/farmacología , Animales , Antiinflamatorios/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Glioblastoma/genética , Glioblastoma/inmunología , Glioblastoma/fisiopatología , Humanos , Lipopolisacáridos/efectos adversos , Macrófagos/inmunología , Ratones , FN-kappa B/genética , FN-kappa B/inmunología , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/inmunología , Enfermedades Neurodegenerativas/fisiopatología , Hojas de la Planta/química , Células RAW 264.7 , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología
12.
BMC Res Notes ; 10(1): 721, 2017 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-29221497

RESUMEN

OBJECTIVES: Though iron deficiency is known to be a major risk factor of anaemia, the association of G6PD deficiency and malaria with anaemia still remains unclear. Hence, a cross-sectional study involving 95 pregnant women visiting Prime Care Hospital in Trans-Ekulu region of Enugu Nigeria was conducted to determine possible predictors of anaemia in pregnancy. RESULTS: The prevalence of anaemia, malaria and G6PD deficiency were 53.7, 12.6 and 60% respectively. Low serum ferritin (OR 5.500, CI 2.25-13.42, p < 0.05) and G6PD deficiency (OR 0.087, CI 0.03-0.23, p < 0.05) were associated with anaemia in pregnancy. On the other hand, malaria did not significantly associate (OR 1.184, CI 0.35-3.97, p = 0.964) with anaemia in pregnant women. These findings showed high prevalence of anaemia among pregnant women with low serum ferritin level and G6PD deficiency as high risk factors of anaemia.


Asunto(s)
Anemia Ferropénica/sangre , Ferritinas/sangre , Deficiencia de Glucosafosfato Deshidrogenasa/sangre , Malaria/sangre , Complicaciones Hematológicas del Embarazo/sangre , Complicaciones Parasitarias del Embarazo/sangre , Adulto , Anemia Ferropénica/epidemiología , Comorbilidad , Estudios Transversales , Femenino , Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Hospitales/estadística & datos numéricos , Humanos , Malaria/epidemiología , Nigeria/epidemiología , Embarazo , Complicaciones Hematológicas del Embarazo/epidemiología , Complicaciones Parasitarias del Embarazo/epidemiología , Adulto Joven
13.
Can J Infect Dis Med Microbiol ; 2017: 1324310, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28932250

RESUMEN

BACKGROUND: Buruli ulcer (BU) continues to be a serious public health threat in wet tropical regions and the mode of transmission of its etiological agent, Mycobacterium ulcerans (MU), remains poorly understood. In this study, mosquito species collected in endemic villages in Benin were screened for the presence of MU. In addition, the ability of mosquitoes larvae to pick up MU from their environment and remain colonized through the larval developmental stages to the adult stage was investigated. METHODS: 7,218 adults and larvae mosquitoes were sampled from endemic and nonendemic villages and screened for MU DNA targets (IS2404, IS2606, and KR-B) using qPCR. Results. MU was not detected in any of the field collected samples. Additional studies of artificially infected larvae of Anopheles kisumu with MU strains revealed that mosquitoes larvae are able to ingest and host MU during L1, L2, L3, and L4 developmental stages. However, we noticed an absence of these bacteria at both pupae and adult stages, certainly revealing the low ability of infected or colonized mosquitoes to vertically transmit MU to their offspring. CONCLUSION: The overall findings highlight the low implication of mosquitoes as biological vectors in the transmission cycle of MU from the risk environments to humans.

14.
BMC Infect Dis ; 17(1): 379, 2017 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-28569148

RESUMEN

BACKGROUND: Drug-resistant tuberculosis, especially multidrug-resistant tuberculosis (MDR-TB), is a major public health problem. Effective management of MDR-TB relies on accurate and rapid diagnosis. In this study, we assessed the diagnostic accuracy of the Genotype MTBDRplus assay in diagnosing MDR-TB in Cameroon, and then discuss on its utility within the diagnostic algorithm for MDR-TB. METHODS: In this cross-sectional study, 225 isolates of Mycobacterium tuberculosis cultured from sputum samples collected from new and previously treated pulmonary tuberculosis patients in Cameroon were used to determine the accuracy of the Genotype MTBDRplus assay. We compared the results of the Genotype MTBDRplus assay with those from the automated liquid culture BACTEC MGIT 960 SIRE system for sensitivity, specificity, and degree of agreement. The pattern of mutations associated with resistance to RIF and INH were also analyzed. RESULTS: The Genotype MTBDRplus assay correctly identified Rifampicin (RIF) resistance in 48/49 isolates (sensitivity, 98% [CI, 89%-100%]), Isoniazid (INH) resistance in 55/60 isolates (sensitivity 92% [CI, 82%-96%]), and MDR-TB in 46/49 (sensitivity, 94% [CI, 83%-98%]). The specificity for the detection of RIF-resistant and MDR-TB cases was 100% (CI, 98%-100%), while that of INH resistance was 99% (CI, 97%-100%). The agreement between the two tests for the detection of MDR-TB was very good (Kappa = 0.96 [CI, 0.92-1.00]). Among the 3 missed MDR-TB cases, the Genotype MTBDRplus assay classified two samples as RIF-monoresistant and one as INH monoresistant. The most frequent mutations detected by the Genotype MTBDRplus assay was the rpoB S531 L MUT3 41/49 (84%) in RIF-resistant isolates, and the KatG S315 T1 (MUT1) 35/55 (64%) and inhA C15T (MUT1) 20/55 (36%) mutations in INH-resistant isolates. CONCLUSION: The Genotype MTBDRplus assay had good accuracy and could be used for the diagnosis of MDR-TB in Cameroon. For routine MDR-TB diagnosis, this assay could be used for Mycobacterium tuberculosis cultures containing contaminants, to complement culture-based drug susceptibility testing or to determine drug resistant mutations.


Asunto(s)
Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Tuberculosis Pulmonar/microbiología , Adulto , Antituberculosos/uso terapéutico , Proteínas Bacterianas/genética , Camerún , Estudios Transversales , Femenino , Genotipo , Técnicas de Genotipaje/métodos , Humanos , Isoniazida/farmacología , Masculino , Pruebas de Sensibilidad Microbiana/métodos , Persona de Mediana Edad , Mutación , Tasa de Mutación , Mycobacterium tuberculosis/aislamiento & purificación , Oxidorreductasas/genética , Rifampin/farmacología , Sensibilidad y Especificidad , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/tratamiento farmacológico
15.
Pathog Glob Health ; 108(7): 323-33, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25388906

RESUMEN

BACKGROUND: In this post-hoc analysis, we determined the influence of single nucleotide polymorphisms in host candidate immune genes on the outcome of drug resistant malaria in Cameroon. METHODS: Human DNA from 760 patients from a previous clinical trial was subjected to mass spectrometry-based single nucleotide polymorphism (SNP) genotyping. Allele frequencies of candidate immune genes were calculated for 62 SNPs on 17 human chromosomes for their possible involvement in clearance of drug-resistant parasites with the triple mutations of pfcrt76T, pfmdr86Y, and pfmdr1246Y (TY) and pfdhfr51I, pfdhfr59R, pfdhfr108N, and pfdhps437G (IRNG) which were determined by dotblot or PCR-restriction analysis. Differences in SNP frequencies and association analysis were carried out by comparing Chi-square odds ratios (ORs) and stratified by Mantel-Haenzel statistics. An adjusted P value (OR) <0·0008 was considered significant. RESULTS: Post-treatment drug failure rates were amodiaquine (36·4%); sulpadoxine/pyrimethamine-amodiaquine combination (15·4%); and sulphadoxine/pyrimethamine (18·1%). SNPs in IL22, IL-4R1, and CD36 appeared to have been associated with clearance of resistant parasites [p  =  0·017, OR (C allele):1·44, 95% CI (OR): 1·06-1·95]; [P  =  0·014, OR  =  1·31, 95% CI (OR): 1·07-1·83]; [P  =  5·78×10(-5), OR  =  0·27, 95%CI (OR): 0·13-0·54], respectively, with high fever (>39°C for 48 hours) [IL-22, P  =  0·01, OR  =  1·5, 95% CI (OR): 1·8-2·1] and also in high frequency among the Fulani participants [P  =  0·006, OR  =  1·83, 95% CI (OR): 1·11-3·08)]. The CD36-1264 null allele was completely absent in the northern population. CONCLUSION: Independent association of SNPs in IL22 and IL-4 with clearance of amodiaquine- and sulphadoxine/pyrimethamine-resistant parasites did not reach statistical significance, but may suggest that not all drug-resistant mutants are adversely affected by the same immune-mediated mechanisms of clearance.


Asunto(s)
Predisposición Genética a la Enfermedad , Interleucina-4/genética , Interleucinas/genética , Malaria Falciparum/genética , Malaria Falciparum/inmunología , Plasmodium falciparum/inmunología , Amodiaquina/farmacología , Antimaláricos/farmacología , Camerún , Preescolar , Combinación de Medicamentos , Resistencia a Medicamentos , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Lactante , Recién Nacido , Malaria Falciparum/parasitología , Masculino , Plasmodium falciparum/efectos de los fármacos , Polimorfismo de Nucleótido Simple , Pirimetamina/farmacología , Sulfadoxina/farmacología
16.
Parasitol Res ; 110(1): 109-17, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21739316

RESUMEN

In a search for new plant-derived antimalarial extracts, 19 fractions were obtained from three Annonaceae species, Uvariopsis congolana (leaf, stem), Polyalthia oliveri (stem bark), and Enantia chlorantha (stem, stem bark) with yields ranging from 0.33% to 4.60%. The extracts were prepared from 500 g of each plant part, using organic solvents to afford five methanolic fractions (acetogenin rich), five water fractions, five hexane fractions, and four interface precipitates. Evaluation of the activity of fractions in vitro against field isolates of the malaria parasite Plasmodium falciparum showed that acetogenin-rich fractions and interface precipitates were the most potent, with IC(50) values ranging from 0.05 to 8.09 µg/ml. Sensitivity of parasite isolates to plant extracts varied greatly, with over 100-fold difference from isolate to isolate in some cases. The active acetogenin-rich fractions and interface precipitates were assessed in combination with chloroquine in the same conditions, and showed additive interaction in the huge majority of cases. Synergistic interactions were found in some cases with acetogenin-rich fractions. Acute toxicity of promising fractions was evaluated through oral administration in Swiss albino mice. Tested fractions appeared to be safe, with LD(50) values higher than 2 g/kg. In summary, acetogenin-rich fractions from Annonaceae species showed high potency against P. falciparum field isolates and safety by oral administration in mice, supporting their detailed investigation for antimalarial drug discovery.


Asunto(s)
Annonaceae/química , Antimaláricos/farmacología , Extractos Vegetales/farmacología , Plasmodium falciparum/efectos de los fármacos , Animales , Antimaláricos/administración & dosificación , Antimaláricos/aislamiento & purificación , Antimaláricos/toxicidad , Camerún , Cloroquina/farmacología , Interacciones Farmacológicas , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Concentración 50 Inhibidora , Dosificación Letal Mediana , Ratones , Pruebas de Sensibilidad Parasitaria , Extractos Vegetales/administración & dosificación , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/toxicidad , Análisis de Supervivencia
17.
J Ethnopharmacol ; 134(3): 717-24, 2011 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-21256952

RESUMEN

AIM OF THE STUDY: In a search for new antimalarial leads, we have carried out a preliminary ethnopharmacological study with the aim of evaluating the in vitro antiplasmodial activity of extracts from thirteen Annonaceae species growing in Cameroon, and of assessing the acute toxicity of promising fractions in Swiss albino mice. MATERIALS AND METHODS: Plants were selected on the basis of an ethnobotanical survey carried out in four sites in centre and south regions of Cameroon (Yaoundé neighbourhoods, Kon-Yambetta, Ngobayang and Mbalmayo) on Annonaceae plants locally used to treat malaria and related symptoms. The choice of the sites was mainly based on environmental factors enabling mosquito breeding, cosmopolitan areas regrouping people from different cultural origins, areas with limited access to health centers, and areas with people relying exclusively on traditional medical practices. Collected materials were extracted by maceration in 95% ethanol. The crude extract was partitioned using organic solvents and the fractions afforded were evaluated for antiplasmodial activity in culture against the W2 strain of Plasmodium falciparum. Promising fractions (methanol fractions) were assessed for their acute toxicity in Swiss albino mice. RESULTS: From the results achieved, 37 (31.3%) out of 118 extracts tested exhibited antiplasmodial activity, with IC(50) values ranging from 1.07 µg/ml to 9.03 µg/ml. Of the active extracts, 29 (78.4%) were methanol fractions, 21 (72.4%) of which inhibited the parasites with IC(50)<5 µg/ml. The promising fractions proved to be safe through oral administration in mice. CONCLUSIONS: The activities and toxicity profiles of methanol fractions indicate that they deserve to be further investigated in detail for antimalarial lead discovery.


Asunto(s)
Annonaceae/química , Antimaláricos/farmacología , Extractos Vegetales/farmacología , Plasmodium/efectos de los fármacos , Animales , Camerún , Femenino , Dosificación Letal Mediana , Masculino , Ratones
18.
J Ethnopharmacol ; 123(3): 483-8, 2009 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-19442463

RESUMEN

AIM OF THE STUDY: In a search for new plant-derived biologically active compounds against malaria parasites, we have carried out an ethnopharmacological study to evaluate the susceptibility of cultured Plasmodium falciparum to extracts and fractions from seven Cameroonian medicinal plants used in malaria treatment. We have also explored the inhibition of the Plasmodium falciparum cysteine protease Falcipain-2. MATERIALS AND METHODS: Plant materials were extracted by maceration in organic solvents, and subsequently partitioned or fractionated to afford test fractions. The susceptibility of erythrocytes and the W2 strain of Plasmodium falciparum to plant extracts was evaluated in culture. In addition, the ability of annonaceous extracts to inhibit recombinant cysteine protease Falcipain-2 was also assessed. RESULTS AND DISCUSSION: The extracts showed no toxicity against erythrocytes. The majority of plant extracts were highly active against Plasmodium falciparumin vitro, with IC(50) values lower than 5 microg/ml. Annonaceous extracts (acetogenin-rich fractions and interface precipitates) exhibited the highest potency. Some of these extracts exhibited modest inhibition of Falcipain-2. CONCLUSION: These results support continued investigation of components of traditional medicines as potential new antimalarial agents.


Asunto(s)
Antimaláricos/farmacología , Magnoliopsida , Malaria Falciparum/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/farmacología , Plantas Medicinales , Plasmodium falciparum/efectos de los fármacos , Animales , Annonaceae , Camerún , Cisteína Endopeptidasas/metabolismo , Eritrocitos/efectos de los fármacos , Etnofarmacología , Euphorbiaceae , Concentración 50 Inhibidora , Medicina Tradicional Africana , Moraceae , Pruebas de Sensibilidad Parasitaria
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