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1.
BMC Infect Dis ; 22(1): 145, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35144535

RESUMO

BACKGROUND: Because of the loss of chloroquine (CQ) effectiveness, the Democratic Republic of Congo (DRC)'s malaria treatment policy replaced CQ by sulfadoxine-pyrimethamine (SP) as first-line treatment of uncomplicated malaria in 2003, which in turn was replaced by artemisinin-based combination therapies (ACT) in 2005. The World Health Organization (WHO) recommends monitoring of anti-malarial drug resistance every 2 years. The study aimed to provide baseline data for biennial molecular surveillance of anti-malarial drug resistance by comparing data from a study conducted in 2019 to previously published data from a similar study conducted in 2017 in the DRC. METHODS: From July to November 2019, a cross-sectional study was conducted in ten sites which were previously selected for a similar study conducted in 2017 across the DRC. P. falciparum malaria was diagnosed by a rapid diagnostic test (RDT) or by microscopy and dried blood samples (DBS) were taken from patients who had a positive test. Segments of interest in pfcrt and pfk13 genes were amplified by conventional PCR before sequencing. RESULTS: Out of 1087 enrolled patients, 906 (83.3%) were PCR-confirmed for P. falciparum. Like in the 2017-study, none of the mutations known to be associated with Artemisinine (ART) resistance in Southeast Asia was detected. However, non-synonymous (NS) mutations with unknown functions were observed among which, A578S was detected in both 2017 and 2019-studies. The overall prevalence of pfcrt-K76T mutation that confers CQ-resistance was 22.7% in 2019-study compared to 28.5% in 2017-study (p-value = 0.069), but there was high variability between sites in the two studies. Like in 2017-study, the pfcrt 72-76 SVMNT haplotype associated with resistance to amodiaquine was not detected. CONCLUSION: The study reported, within 2 years, the non-presence of molecular markers currently known to be associated with resistance to ART and to AQ in P. falciparum isolated in the DRC. However, the presence of polymorphisms with as-yet unknown functions was observed, requiring further characterization. Moreover, an overall decrease in the prevalence of CQ-resistance marker was observed in the DRC, but this prevalence remained highly variable from region to region.


Assuntos
Antimaláricos , Malária Falciparum , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Estudos Transversais , República Democrática do Congo/epidemiologia , Combinação de Medicamentos , Resistência a Medicamentos/genética , Humanos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Plasmodium falciparum/genética , Proteínas de Protozoários/genética
2.
Malar J ; 20(1): 144, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33706773

RESUMO

BACKGROUND: The national policy for malaria treatment of the Democratic Republic of Congo recommends two first-line artemisinin-based combinations for the treatment of uncomplicated malaria: artesunate-amodiaquine and artemether-lumefantrine. This study investigated the presence of markers associated with resistance to the current first-line artemisinin-based combination therapy (ACT) in isolates of Plasmodium falciparum from treatment failure patients in the Democratic Republic of Congo. METHODS: From November 2018 to November 2019, dried blood spots were taken from patients returning to health centres for fever within 28 days after an initial malaria treatment in six sentinel sites of the National Malaria Control Programme across Democratic Republic of Congo. The new episode of malaria was first detected by a rapid diagnostic test and then confirmed by a real-time PCR assay to define treatment failure. Fragments of interest in pfk13 and pfcrt genes were amplified by conventional PCR before sequencing and the Pfmdr1 gene copy number was determined by a TaqMan real-time PCR assay. RESULTS: Out of 474 enrolled patients, 364 (76.8%) were confirmed positive by PCR for a new episode of P. falciparum malaria, thus considered as treatment failure. Of the 325 P. falciparum isolates obtained from 364 P. falciparum-positive patients and successfully sequenced in the pfk13-propeller gene, 7 (2.2%) isolates carried non-synonymous mutations, among which 3 have been previously reported (N498I, N554K and A557S) and 4 had not yet been reported (F506L, E507V, D516E and G538S). Of the 335 isolates successfully sequenced in the pfcrt gene, 139 (41.5%) harboured the K76T mutation known to be associated with chloroquine resistance. The SVMNT haplotype associated with resistance to amodiaquine was not found. None of the isolates carried an increased copy number of the pfmdr1 gene among the 322 P. falciparum isolates successfully analysed. CONCLUSION: No molecular markers currently known to be associated with resistance to the first-line ACT in use were detected in isolates of P. falciparum from treatment failure patients. Regular monitoring through in vivo drug efficacy and molecular studies must continue to ensure the effectiveness of malaria treatment in Democratic Republic of Congo.


Assuntos
Amodiaquina/farmacologia , Antimaláricos/farmacologia , Combinação Arteméter e Lumefantrina/farmacologia , Artemisininas/farmacologia , Resistência a Medicamentos/genética , Proteínas de Membrana Transportadoras/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , República Democrática do Congo , Combinação de Medicamentos , Feminino , Marcadores Genéticos/genética , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Falha de Tratamento , Adulto Jovem
3.
Malar J ; 19(1): 121, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32197607

RESUMO

BACKGROUND: The loss of chloroquine (CQ) effectiveness has led to its withdrawal from national policies as a first-line treatment for uncomplicated malaria in several endemic countries, such as the Democratic Republic of Congo (DRC). The K76T mutation on the pfcrt gene has been identified as a marker of CQ resistance and the SVMNT haplotype in codons 72-76 on the same gene has been associated with resistance to amodiaquine (AQ). In the DRC, the prevalence of K76T has decreased from 100% in 2000 to 63.9% in 2014. The purpose of this study was to determine the prevalence of K76T mutations in circulating strains of Plasmodium falciparum, 16 years after CQ withdrawal in the DRC and to investigate the presence of the SVMNT haplotype. METHODS: In 2017, ten geographical sites across the DRC were selected. Dried blood samples were collected from patients attending health centres. Malaria was first detected by a rapid diagnostic test (RDT) available on site (SD Bioline Malaria Ag Pf or CareStart Malaria Pf) or thick blood smear and then confirmed by a P. falciparum species-specific real-time PCR assay. A pfcrt gene segment containing a fragment that encodes amino acids at positions 72-76 was amplified by conventional PCR before sequencing. RESULTS: A total of 1070 patients were enrolled. Of the 806 PCR-confirmed P. falciparum positive samples, 764 were successfully sequenced. The K76T mutation was detected in 218 samples (28.5%; 95% CI 25.4%-31.9%), mainly (96%) with the CVIET haplotype. Prevalence of CQ resistance marker was unequally distributed across the country, ranging from 1.5% in Fungurume to 89.5% in Katana. The SVMNT haplotype, related to AQ resistance, was not detected. CONCLUSION: Overall, the frequency of the P. falciparum CQ resistance marker has decreased significantly and no resistance marker to AQ was detected in the DRC in 2017. However, the between regions variability of CQ resistance remains high in the country. Further studies are needed for continuous monitoring of the CQ resistance level for its prospective re-use in malaria management. The absence of the AQ resistance marker is in line with the use of this drug in the current DRC malaria treatment policy.


Assuntos
Amodiaquina/uso terapêutico , Antimaláricos/uso terapêutico , Cloroquina/uso terapêutico , Resistência a Medicamentos/genética , Malária Falciparum/tratamento farmacológico , Proteínas de Membrana Transportadoras/genética , Proteínas de Protozoários/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , República Democrática do Congo/epidemiologia , Teste em Amostras de Sangue Seco , Humanos , Lactente , Recém-Nascido , Malária Falciparum/epidemiologia , Programas de Rastreamento , Pessoa de Meia-Idade , Mutação , Plasmodium falciparum/genética , Polimorfismo Genético , Estudos Prospectivos , Adulto Jovem
4.
Malar J ; 14: 354, 2015 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-26376639

RESUMO

BACKGROUND: Malaria cases were estimated to 207 million in 2013. One of the problems of malaria control is the emergence and spread of Plasmodium falciparum strains that become resistant to almost all drugs available. Monitoring drug resistance is essential for early detection and subsequent prevention of the spread of drug resistance by timely changes of treatment policy. This review was performed to gather all data available on P. falciparum molecular resistance in DR Congo, as baseline for future assessments. METHODS: The search for this review was undertaken using the electronic databases PubMed and Google Scholar using the terms "malaria", "Congo", "resistance", "molecular", "antimalarial", "efficacy". Articles were classified based on year of collecting, year of publication, sample size and characteristics, molecular markers analysed and polymorphisms detected. RESULTS: Thirteen articles were included and five genes have been analysed in these studies: pfcrt, pfdhps, pfdhfr, pfmdr1 and K13-propeller. The majority of studies included were not representative of the whole country. CONCLUSION: This systematic review demonstrates the lack of molecular resistance studies in DRC. Only 13 studies were identified in almost 15 years. The MOH must implement a national surveillance system for monitoring malaria drug resistance and this surveillance should be conducted frequently and country-representative.


Assuntos
Resistência a Medicamentos/genética , Malária Falciparum/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , República Democrática do Congo , Humanos , Mutação/genética
5.
Malar J ; 11: 289, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22909422

RESUMO

BACKGROUND: Natural products could play an important role in the challenge to discover new anti-malarial drugs. In a previous study, Dicoma tomentosa (Asteraceae) was selected for its promising anti-plasmodial activity after a preliminary screening of several plants traditionally used in Burkina Faso to treat malaria. The aim of the present study was to further investigate the anti-plasmodial properties of this plant and to isolate the active anti-plasmodial compounds. METHODS: Eight crude extracts obtained from D. tomentosa whole plant were tested in vitro against two Plasmodium falciparum strains (3D7 and W2) using the p-LDH assay (colorimetric method). The Peters' four-days suppressive test model (Plasmodium berghei-infected mice) was used to evaluate the in vivo anti-plasmodial activity. An in vitro bioguided fractionation was undertaken on a dichloromethane extract, using preparative HPLC and TLC techniques. The identity of the pure compound was assessed using UV, MS and NMR spectroscopic analysis. In vitro cytotoxicity against WI38 human fibroblasts (WST-1 assay) and haemolytic activity were also evaluated for extracts and pure compounds in order to check selectivity. RESULTS: The best in vitro anti-plasmodial results were obtained with the dichloromethane, diethylether, ethylacetate and methanol extracts, which exhibited a high activity (IC50 ≤ 5 µg/ml). Hot water and hydroethanolic extracts also showed a good activity (IC50 ≤ 15 µg/ml), which confirmed the traditional use and the promising anti-malarial potential of the plant. The activity was also confirmed in vivo for all tested extracts. However, most of the active extracts also exhibited cytotoxic activity, but no extract was found to display any haemolytic activity. The bioguided fractionation process allowed to isolate and identify a sesquiterpene lactone (urospermal A-15-O-acetate) as the major anti-plasmodial compound of the plant (IC50 < 1 µg/ml against both 3D7 and W2 strains). This was also found to be the main cytotoxic compound (SI = 3.3). While this melampolide has already been described in the plant, this paper is the first report on the biological properties of this compound. CONCLUSIONS: The present study highlighted the very promising anti-plasmodial activity of D. tomentosa and enabled to identify its main active compound, urospermal A-15-O-acetate. The high anti-plasmodial activity of this compound merits further study about its anti-plasmodial mechanism of action. The active extracts of D. tomentosa, as well as urospermal A 15-O-acetate, displayed only a moderate selectivity, and further studies are needed to assess the safety of the use of the plant by the local population.


Assuntos
Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Asteraceae/química , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Acetatos/química , Acetatos/isolamento & purificação , Acetatos/farmacologia , Acetatos/uso terapêutico , Animais , Antimaláricos/química , Antimaláricos/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Burkina Faso , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Modelos Animais de Doenças , Fibroblastos/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Malária/tratamento farmacológico , Camundongos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plasmodium berghei/efeitos dos fármacos , Plasmodium berghei/patogenicidade , Plasmodium falciparum/efeitos dos fármacos , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Sesquiterpenos/uso terapêutico , Análise Espectral , Resultado do Tratamento
6.
BMC Infect Dis ; 12: 53, 2012 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-22405322

RESUMO

BACKGROUND: There is no information regarding the resistance mechanisms of extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae in community setting in Cameroon. The current study aimed to determine the proportion of ESBLs in Enterobacteriaceae isolated in the community and to analyse some risk factors associated with ESBL carriage. METHODS: Faecal samples were collected from 208 different outpatients and 150 healthy student volunteers between 3 January and 3 April 2009. Enterobacterial isolates resistant to third-generation cephalosporins were screened for ESBL production by the double-disk synergy test. Presumptive ESBL-producing isolates with positive synergy test were identified by Mass Spectrometry using the BioTyper MALDI-TOF. For such ESBL positive isolates, antibiotic susceptibility was determined by the Vitek 2 system. PCR and sequencing were performed for the detection of different types of ESBL genes in presumptive ESBL-producing isolates. Statistical methods were used for the univariate calculation of risk factors. RESULTS: During the study period, a total of 358 faecal samples were analysed; 58 of such samples (16%) showed an ESBL phenotype and were confirmed by PCR. The proportion of ESBL producers in faecal carriage was statistically different between outpatients and student volunteers (23.1% vs. 6.7%: p < 0.000). According to a univariate analysis, previous use of antibiotics (ciprofloxacin) appeared to be a risk factor for ESBL carriage (p < 0.05).Escherichia coli was the species most frequently isolated among the ESBL producers in outpatients (66.7%) and student volunteers (90%). Isolates showed additional resistance to gentamicin, ciprofloxacin and trimethoprim/sulfamethoxazole but none of them was resistant to temocillin, amikacin or meropenem. Most of the strains (97%) produced a CTX-M group 1 enzymes [CTX-M-15 (98%) or CTX-M-1 (2%)] and the remaining strains produced SHV-12 enzyme (3%). CONCLUSIONS: The use of drugs such as amoxicillin, ciprofloxacin and trimethoprim/sulfamethoxazole does not seem appropriate for empirical treatment because of emerging resistance. The implementation in Cameroon or in other African countries of methods of screening ESBL-producing organisms in routine laboratories is of great importance in order for us to offer patients appropriate treatment and for infection control efforts to succeed.


Assuntos
Portador Sadio/epidemiologia , Infecções Comunitárias Adquiridas/epidemiologia , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/enzimologia , beta-Lactamases/metabolismo , Adulto , Camarões/epidemiologia , Portador Sadio/microbiologia , Cefalosporinas/farmacologia , Infecções Comunitárias Adquiridas/microbiologia , Uso de Medicamentos/estatística & dados numéricos , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Fezes/microbiologia , Feminino , Experimentação Humana , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pacientes Ambulatoriais , Reação em Cadeia da Polimerase , Fatores de Risco , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Resistência beta-Lactâmica , beta-Lactamases/química , beta-Lactamases/genética , beta-Lactamases/isolamento & purificação
7.
Lancet Infect Dis ; 21(4): e82-e92, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33125913

RESUMO

The spread of Plasmodium falciparum isolates carrying mutations in the kelch13 (Pfkelch13) gene associated with artemisinin resistance (PfART-R) in southeast Asia threatens malaria control and elimination efforts. Emergence of PfART-R in Africa would result in a major public health problem. In this systematic review, we investigate the frequency and spatial distribution of Pfkelch13 mutants in Africa, including mutants linked to PfART-R in southeast Asia. Seven databases were searched (PubMed, Embase, Scopus, African Journal Online, African Index Medicus, Bioline, and Web of Science) for relevant articles about polymorphisms of the Pfkelch13 gene in Africa before January, 2019. Following PRISMA guidelines, 53 studies that sequenced the Pfkelch13 gene of 23 100 sample isolates in 41 sub-Saharan African countries were included. The Pfkelch13 sequence was highly polymorphic (292 alleles, including 255 in the Pfkelch13-propeller domain) but with mutations occurring at very low relative frequencies. Non-synonymous mutations were found in only 626 isolates (2·7%) from west, central, and east Africa. According to WHO, nine different mutations linked to PfART-R in southeast Asia (Phe446Ile, Cys469Tyr, Met476Ile, Arg515Lys, Ser522Cys, Pro553Leu, Val568Gly, Pro574Leu, and Ala675Val) were detected, mainly in east Africa. Several other Pfkelch13 mutations, such as those structurally similar to southeast Asia PfART-R mutations, were also identified, but their relevance for drug resistance is still unknown. This systematic review shows that Africa, thought to not have established PfART-R, reported resistance-related mutants in the past 5 years. Surveillance using PfART-R molecular markers can provide valuable decision-making information to sustain the effectiveness of artemisinin in Africa.


Assuntos
Artemisininas/farmacologia , Resistência a Medicamentos/genética , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , África/epidemiologia , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Genes de Protozoários/genética , Humanos , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Mutação , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/isolamento & purificação , Polimorfismo de Nucleotídeo Único
8.
Med Mycol ; 48(7): 969-74, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20199171

RESUMO

A study was carried out over a 4-month winter period in order to assess the presence of filamentous fungi in the water distribution system of the University Hospital of Liège. A total of 197 hot and cold water samples were collected from the main water supply lines and from the taps at three different hospital sites. Overall, filamentous fungi were recovered from 55% and 50% of the main water distribution system and tap water samples, respectively, with a mean of 3.5 ± 1.5 colony forming units per 500 ml water. Nine different genera were identified, all belonging to the Hyphomycetes class. Aspergillus spp. were recovered from 6% of the samples of the water distribution system and A. fumigatus was the most frequently recovered species (66.6%). However, this species was not isolated from water taps. Fusarium spp. was predominant at one site, where it was found in 28% of tap water samples. No Aspergillus spp. but some Fusarium spp. isolates were identified in samples collected from high-risk units. Filters were introduced at the point-of-use in the haematology unit after completion of the study. The findings of the present study confirm the need for further documented studies to evaluate the safety of the hospital water system and to define new preventive measures.


Assuntos
Fungos/isolamento & purificação , Hospitais Universitários , Micoses/epidemiologia , Microbiologia da Água , Abastecimento de Água/análise , Aspergillus/isolamento & purificação , Bélgica/epidemiologia , Contagem de Colônia Microbiana , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Fungos/classificação , Fusarium/isolamento & purificação , Humanos , Micoses/prevenção & controle , Fatores de Risco
9.
PLoS One ; 15(8): e0237791, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822392

RESUMO

Artemisinin-based combination therapies (ACTs) have been recommended by the World Health Organization (WHO) as first-line treatment of uncomplicated Plasmodium falciparum (P. falciparum) malaria since 2005 in Democratic Republic of Congo (DRC) and a regular surveillance of the ACT efficacy is required to ensure the treatment effectiveness. Mutations in the propeller domain of the pfk13 gene were identified as molecular markers of artemisinin resistance (ART-R). This study investigated the pfk13-propeller gene polymorphism in clinical isolates of P. falciparum collected in the DRC. In 2017, ten geographical sites across DRC were selected for a cross-sectional study that was conducted first in Kinshasa from January to March, then in the nine other sites from September to December. Dried blood samples were collected from patients attending health centers for fever where diagnosis of Malaria was first made by rapid diagnostic test (RDT) available on site (SD Bioline malaria Ag Pf or CareStart Malaria Pf) or by thick blood smear and then confirmed by a P. falciparum real-time PCR assay. A pfk13-propeller segment containing a fragment that codes for amino acids at positions 427-595 was amplified by conventional PCR before sequencing. In total, 1070 patients were enrolled in the study. Real-time PCR performed confirmed the initial diagnosis of P. falciparum infection in 806 samples (75.3%; 95% CI: 72.6%- 77.9%). Of the 717 successfully sequenced P. falciparum isolates, 710 (99.0%; 95% CI: 97.9% - 99.6) were wild-type genotypes and 7 (1.0%; 95% CI: 0.4% - 2.1%) carried non-synonymous (NS) mutations in pfk13-propeller including 2 mutations (A578S and V534A) previously detected and 2 other (M472I and A569T) not yet detected in the DRC. Mutations associated with ART-R in Southeast Asia were not observed in DRC. However, the presence of other mutations in pfk13-propeller gene calls for further investigations to assess their implication in drug resistance.


Assuntos
Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Adolescente , Adulto , Idoso , Antimaláricos/farmacologia , Artemisininas/farmacologia , Criança , Pré-Escolar , República Democrática do Congo/epidemiologia , Resistência a Medicamentos , Feminino , Humanos , Malária Falciparum/parasitologia , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo Genético , Adulto Jovem
10.
Travel Med Infect Dis ; 5(4): 236-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17574145

RESUMO

BACKGROUND: Two elderly people among a group of eight Belgian travellers who had stayed in Turkey for 2 weeks, developed a severe enteritis shortly after their return to Belgium. They had travelled by private bus, and had visited different places during their stay in Turkey from 6 to 17 September 2005. METHODS: After notification an epidemiological study was conducted by the Public Health authorities in Antwerp to identify the cause of the infection, to detect other cases, and to trace the source in Turkey. Vibrio cholerae was isolated from stools and a slide agglutination test was performed at the reference laboratory for cholera in Belgium. RESULTS: V. cholerae O1, El Tor, Inaba was identified in the stools of two patients. Four other patients, who suffered from a milder form of the disease, met the case definition of probable cases. No secondary infections among their contacts in Belgium were found. In spite of an epidemiological search conducted by the Turkish Public Health authorities, other cases of cholera in Turkey could not be detected. Nor a source for the outbreak could be established. CONCLUSIONS: The outbreak of imported cholera in Belgium stresses the risk of contracting cholera in a country not considered as a cholera endemic region. It highlights the need for careful laboratory surveillance of intestinal infections in travellers after their return to their homeland. Early detection and prompt reporting are recommended.


Assuntos
Cólera/epidemiologia , Surtos de Doenças , Viagem , Idoso , Bélgica/epidemiologia , Cólera/etiologia , Cólera/prevenção & controle , Fezes/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Turquia , Vibrio cholerae O1/isolamento & purificação , Vibrio cholerae O139/isolamento & purificação
11.
PLoS One ; 12(6): e0179142, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28594879

RESUMO

Malaria is a major public health problem in the Democratic Republic of Congo. Despite progress achieved over the past decade in the fight against malaria, further efforts have to be done such as in the surveillance and the containment of Plasmodium falciparum resistant strains. We investigated resistance to artemisinin-based combination therapies currently in use in Democratic Republic of Congo by surveying molecular polymorphisms in three genes: pfcrt, pfmdr1 and pfk13 to explore possible emergence of amodiaquine, lumefantrine or artemisinin resistance in Democratic Republic of Congo. This study essentially revealed that resistance to chloroquine is still decreasing while polymorphism related to amodiaquine resistance seems to be not present in Democratic Republic of Congo, that three samples, located in the east of the country, harbor Pfmdr1 amplification and that none of the mutations found in South-East Asia correlated with artemisinine resistance have been found in Democratic Republic of Congo. But new mutations have been identified, especially the M476K, occurred in the same position that the M476I previously identified in the F32-ART strain, strongly resistant to artemisinine. Antimalarial first-line treatments currently in use in Democratic Republic of Congo are not associated with emergence of molecular markers of resistance.


Assuntos
Artemisininas/uso terapêutico , Resistência a Medicamentos/genética , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Plasmodium falciparum/genética , República Democrática do Congo , Quimioterapia Combinada , Dosagem de Genes , Marcadores Genéticos , Geografia , Haplótipos/genética , Humanos , Mutação/genética , Polimorfismo Genético , Proteínas de Protozoários/genética
12.
Intensive Care Med ; 32(1): 67-74, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16308683

RESUMO

OBJECTIVE: To determine the effect of antibiotic class pressure on the susceptibility of bacteria during sequential periods of antibiotic homogeneity. DESIGN AND SETTING: Prospective study in a mixed ICU with three separated subunits of eight, eight, and ten beds. PATIENTS AND PARTICIPANTS: The study examined the 1,721 patients with a length of stay longer than 2 days. INTERVENTIONS: Three different antibiotic regimens were used sequentially over 2 years as first-choice empirical treatment: cephalosporins, fluoroquinolone, or a penicillin-beta-lactamase inhibitor combination. Each regimen was applied for 8 months in each subunits of the ICU, using "latin square" design. RESULTS: We treated 731 infections in 546 patients (32% of patients staying more than 48 h). There were 25.5 ICU-acquired infections per 1,000 patient-days. Infecting pathogens and colonizing bacteria were found in 2,739 samples from 1,666 patients (96.8%). No significant change in global antibiotic susceptibility was observed over time. However, a decrease in the susceptibility of several species was observed for antibiotics used as the first-line therapy in the unit. Selection pressure of antibiotics and occurrence of resistance during treatment was documented within an 8-month rotation period. CONCLUSIONS: Antibiotic use for periods of several months induces bacterial resistance in common pathogens.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Controle de Infecções/métodos , Antibacterianos/farmacologia , Bélgica , Cefalosporinas/farmacologia , Cefalosporinas/uso terapêutico , Combinação de Medicamentos , Uso de Medicamentos , Fluoroquinolonas/farmacologia , Fluoroquinolonas/uso terapêutico , Humanos , Unidades de Terapia Intensiva , Pessoa de Meia-Idade , Penicilinas/farmacologia , Penicilinas/uso terapêutico , Estudos Prospectivos , Inibidores de beta-Lactamases
13.
Malar Res Treat ; 2016: 5405802, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26942036

RESUMO

Malaria remains a major public health problem in the Democratic Republic of Congo (DRC) with 14 million cases reported by the WHO Malaria Report in 2014. Asymptomatic malaria cases are known to be prevalent in endemic areas and are generally untreated, resulting in a significant source of gametocytes that may serve as reservoir of disease transmission. Considering that microscopy certainly underestimates the prevalence of Plasmodium infections within asymptomatic carriers and that PCR assays are currently recognized as the most sensitive methods for Plasmodium identification, this study was conducted to weigh the asymptomatic carriage in DRC by a molecular method. Six provinces were randomly selected for blood collection in which 80 to 100 individuals were included in the study. Five hundred and eighty blood samples were collected and molecular diagnosis was performed. Globally, almost half of the samples collected from asymptomatic individuals (280/580; 48.2%) had Plasmodium infections and the most species identified was P. falciparum alone in combination with P. malariae. The high prevalence reported here should interpellate the bodies involved in malaria control in DR Congo to take into account asymptomatic carriers in actions taken and consider asymptomatic malaria as a major hurdle for malaria elimination.

14.
Int J Parasitol Parasites Wildl ; 5(1): 1-4, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27141437

RESUMO

Plasmodiums are protozoa that may infect various hosts. Only five species are now recognized as naturally parasitizing humans: Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, Plasmodium ovale and Plasmodium knowlesi. This fifth species, P. knowlesi, previously identified as naturally parasitizing the monkey Macaca fascicularis, has been microscopically confused for a long time with P. malariae or P. falciparum and it was not possible to correctly differentiate them until the advent of molecular biology. To date, natural human infections with P. knowlesi only occur in Southeast Asia and a similar phenomenon of natural transmission of simian plasmodium to humans has not been reported elsewhere. This study was conducted to investigate a possible transmission of African small monkey's plasmodium to humans in populations living near the rainforest of the Democratic Republic of Congo (DRC) where several species of non-human primates are living. Two successive real-time PCRs were identified in the literature and used in combination for purpose. Only P. falciparum was found in this study. However, studies with larger samples and with more advanced techniques should be conducted.

15.
J Ethnopharmacol ; 97(3): 535-9, 2005 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-15740892

RESUMO

The antiplasmodial activity of crude extracts of 19 species of Strychnos (Loganiaceae) was assessed in vitro against a chloroquine-susceptible strain of Plasmodium falciparum. For each species, ethyl acetate (EtOAc) extracts were analysed and, for the most active species, methanolic (MeOH) extracts were also tested. Among them, Strychnos variabilis De Wild. seemed to be very promising (inhibitory concentration 50% (IC50) < 5 microg/ml) whereas two other species, Strychnos gossweileri Exell and Strychnos mellodora S. Moore, could be interesting (IC50 < 15 microg/ml) in further antimalarial studies.


Assuntos
Antiprotozoários/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Strychnos , Animais , Antiprotozoários/isolamento & purificação , Avaliação Pré-Clínica de Medicamentos/métodos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Estruturas Vegetais , Plasmodium falciparum/fisiologia
16.
Curr Med Chem ; 9(15): 1435-56, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12173975

RESUMO

Malaria is the major parasitic infection in many tropical and subtropical regions, leading to more than one million deaths (principally young African children) out of 400 million cases each year (WHO world health report 2000). More than half of the world's population live in areas where they remain at risk of malaria infection. During last years, the situation has worsened in many ways, mainly due to malarial parasites becoming increasingly resistant to several antimalarial drugs. Furthermore, the control of malaria is becoming more complicated by the parallel spread of resistance of the mosquito vector to currently available insecticides. Discovering new drugs in this field is therefore a health priority. Several new molecules are under investigation. This review describes the classical treatments of malaria and the latest discoveries in antimalarial agents, especially artemisinin and its recent derivatives as well as the novel peroxidic compounds.


Assuntos
Antimaláricos/farmacologia , Plasmodium/efeitos dos fármacos , Animais , Antimaláricos/uso terapêutico , Artemisininas/química , Artemisininas/classificação , Artemisininas/farmacologia , Resistência a Medicamentos , Humanos , Inibidores da Síntese de Ácido Nucleico/classificação , Inibidores da Síntese de Ácido Nucleico/farmacologia , Plasmodium/metabolismo , Plasmodium/parasitologia , Inibidores da Síntese de Proteínas/classificação , Inibidores da Síntese de Proteínas/farmacologia , Quinolinas/química , Quinolinas/classificação , Quinolinas/farmacologia , Sesquiterpenos/química , Sesquiterpenos/classificação , Sesquiterpenos/farmacologia
17.
Pediatr Infect Dis J ; 23(8): 739-47, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15295224

RESUMO

BACKGROUND: In-hospital mortality from lower respiratory tract infections (LTRI) is unacceptably high in developing countries where LTRI are still a leading cause of death. OBJECTIVE: To identify new approaches to reduce in-hospital mortality of LRTI through the improvement of its management. METHODS: The prospectively collected database of children admitted during an 11-year period with LRTI in a pediatric rural hospital in Central Africa was reviewed to determine the predictors of death and to evaluate the impact on mortality of 4 different protocols for the management of malnutrition. RESULTS: During the study period, 859 children were admitted with a nonmeasles severe LRTI. In the 3-year period during which blood cultures were obtained, 29.0% of the children with LRTI were bacteremic, and multiresistant Enterobacteriaceae were recovered in 81.4% of positive blood cultures. Independent predictors of death in children without edema were age <24 months, dehydration and hepatomegaly with adjusted odds ratios (numbers in parentheses, 95% confidence interval) of 3.47 (1.70-7.08), 4.24 (2.11-8.50) and 2.90 (1.43-5.85), respectively. In those with edema, a significantly increased risk of death was noted for girls [4.31 (1.71-10.90)], in children with z-score of weight to height < or = -3 [5.45 (1.67-17.79)] and when the serum albumin was <16 g/l [2.58 (1.01-6.58)]. The improvement in the management of malnutrition was followed by a reduction of LRTI-related mortality in children with edema from 32.4 to 8.9% (P < 0.001). In children without edema, the LRTI-related mortality decreased from approximately 12% to 3.5% when their diet was supplemented with micronutrients. CONCLUSION: This study indicates that the improvement of the management of underlying nutritional deficiencies is crucial for the reduction of the high in-hospital case fatality rate associated with severe nonmeasles LRTI. The empiric antibiotic regimen should be modified to cover for multiresistant Enterobacteriaceae.


Assuntos
Mortalidade Hospitalar/tendências , Mortalidade Infantil/tendências , Desnutrição/terapia , Apoio Nutricional , Infecções Respiratórias/mortalidade , Infecções Respiratórias/prevenção & controle , Fatores Etários , Criança , Pré-Escolar , Congo/epidemiologia , Bases de Dados Factuais , Desidratação , Edema/complicações , Feminino , Hepatomegalia , Hospitais Rurais/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Desnutrição/complicações , Estado Nutricional , Estudos Prospectivos , Fatores de Risco , População Rural
18.
Phytochemistry ; 62(4): 623-9, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12560037

RESUMO

In the course of our search for new antiplasmodial alkaloids from Strychnos icaja, we have isolated five alkaloids: three monomers, protostrychnine and genostrychnine, previously described in Strychnos nux-vomica, pseudostrychnine, already found in the leaves of the plant, a new bisindolic alkaloid, named strychnogucine C, and the first naturally occurring trimeric indolomonoterpenic alkaloid: strychnohexamine. This latter trimeric alkaloid presented an antiplasmodial activity against the FCA Plasmodium falciparum line near 1 microM.


Assuntos
Antimaláricos/isolamento & purificação , Carbazóis/isolamento & purificação , Alcaloides Indólicos/isolamento & purificação , Monoterpenos/isolamento & purificação , Plasmodium falciparum/efeitos dos fármacos , Estricnina/isolamento & purificação , Strychnos/química , Animais , Antimaláricos/química , Antimaláricos/farmacologia , Carbazóis/química , Carbazóis/farmacologia , República Democrática do Congo , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacologia , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Monoterpenos/química , Monoterpenos/farmacologia , Raízes de Plantas/química , Estereoisomerismo , Estricnina/análogos & derivados , Estricnina/química , Estricnina/farmacologia
19.
J Periodontol ; 73(1): 73-8, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11846202

RESUMO

BACKGROUND: Periodontitis has recently been identified as a potential risk factor for systemic pathologies such as cardiovascular disease, the hypothesis being that periodontal pockets could release pro-inflammatory bacterial components, for instance endotoxins, into the bloodstream. It is known that the oral cavity can be a source of circulating bacteria, but this has never been shown for bacterial endotoxins, and no evidence exists so far that the risk of systemic injury is related to the severity of periodontitis. The aim of the present study was to test the influence of gentle mastication on the occurrence of endotoxemia in patients with or without periodontal disease. METHODS: A total of 67 subjects were periodontally examined and grouped according to their periodontal status. This classification was based on an original index of severity of periodontal disease (periodontal index for risk of infectiousness, PIRI) aimed at reflecting the individual risk of systemic injury from the periodontal niches. Thus, the patients were classified into 3 risk groups: low, PIRI = 0; n = 25; moderate, 1 < or = PIRI < or = 5, n = 27; and high 6 < or = PIRI < or = 10, n = 15. Blood samples were collected before and 5 to 10 minutes after a standardized session of gentle mastication for detection of circulating endotoxins. Blood samples were tested with a chromogenic limulus amoebocyte lysate assay. RESULTS: Overall, blood levels of endotoxin after mastication were found to be significantly higher than before mastication (0.89 +/- 3.3 pg/ml versus 3.0 +/- 5.8 pg/ml; P= 0.0002). Likewise, the incidence of positive endotoxemia rose from 6% before mastication to 24% after mastication (P = 0.001). When accounting for the PIRI index, endotoxin levels and positive endotoxemia proved to be significantly higher in patients with severe periodontal disease than in the subjects with low or moderate periodontitis. CONCLUSIONS: Gentle mastication is able to induce the release of bacterial endotoxins from oral origin into the bloodstream, especially when patients have severe periodontal disease. This finding suggests that a diseased periodontium can be a major and underestimated source of chronic, or even permanent, release of bacterial pro-inflammatory components into the bloodstream.


Assuntos
Endotoxinas/sangue , Mastigação/fisiologia , Periodontite/classificação , Adulto , Compostos Cromogênicos , Endotoxemia/etiologia , Feminino , Defeitos da Furca/classificação , Defeitos da Furca/microbiologia , Hemorragia Gengival/classificação , Hemorragia Gengival/microbiologia , Humanos , Mediadores da Inflamação/sangue , Teste do Limulus , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , Bolsa Periodontal/classificação , Bolsa Periodontal/microbiologia , Periodontite/microbiologia , Fatores de Risco , Estatística como Assunto
20.
J Infect Dev Ctries ; 8(2): 168-75, 2014 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-24518626

RESUMO

BACKGROUND: The prevalence of Campylobacter jejuni and Campylobacter coli was determined in goat and goat meat sold at retail outlets in Lubumbashi, Democratic Republic of Congo (DR Congo). METHODOLOGY: A total of 644 samples, including 177 goat meat, 86 goat stomachs, 139 ready to eat (RTE) goat skewers, and 242 goat faecal samples were examined for the presence of Campylobacter jejuni and Campylobacter coli using polymerase chain reaction. RESULTS: Overall, Campylobacter spp. were found in 34.6% of the examined samples. C. jejuni was isolated in 10.1% and C. coli in 26.7% of samples. Only 2.2% of all samples were positive for both species. There was a significant association between the prevalence of C. coli and the type of sample (p < 0.05). The overall prevalence of Campylobacter in different sample groups was 41.2%, 37.2%, 23.7%, and 35.1% for goat meat, goat stomachs, RTE goat skewers, and goat faecal samples, respectively. There was no significant difference (p > 0.05) between the prevalence observed in the rainy season (16.7%) and the dry season (20.0%). Moreover, the overall prevalence of Campylobacter in slaughter sites, open-air markets, warehouses, and semi-open-air markets was 28.2%, 34.2%, 35.4%, and 42.9%, respectively. Statistically, there was no influence of the sample collection site on the frequency of isolation of Campylobacter (p > 0.05). CONCLUSION: This study shows that, considering the relatively high prevalence of this pathogen, live goat and goat meat are major sources of human and environmental contamination by Campylobacter spp. in Lubumbashi.


Assuntos
Campylobacter coli/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , Contaminação de Alimentos/análise , Cabras/microbiologia , Carne/microbiologia , Animais , Congo , DNA Bacteriano/isolamento & purificação , Fezes/microbiologia , Microbiologia de Alimentos , Reação em Cadeia da Polimerase
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