RESUMO
A recent randomized controlled trial, the WANECAM (West African Network for Clinical Trials of Antimalarial Drugs) trial, conducted at seven centers in West Africa, found that artemether-lumefantrine, artesunate-amodiaquine, pyronaridine-artesunate, and dihydroartemisinin-piperaquine all displayed good efficacy. However, artemether-lumefantrine was associated with a shorter interval between clinical episodes than the other regimens. In a further comparison of these therapies, we identified cases of persisting submicroscopic parasitemia by quantitative PCR (qPCR) at 72 h posttreatment among WANECAM participants from 5 sites in Mali and Burkina Faso, and we compared treatment outcomes for this group to those with complete parasite clearance by 72 h. Among 552 evaluable patients, 17.7% had qPCR-detectable parasitemia at 72 h during their first treatment episode. This proportion varied among sites, reflecting differences in malaria transmission intensity, but did not differ among pooled drug treatment groups. However, patients who received artemether-lumefantrine and were qPCR positive at 72 h were significantly more likely to have microscopically detectable recurrent Plasmodium falciparum parasitemia by day 42 than those receiving other regimens and experienced, on average, a shorter interval before the next clinical episode. Haplotypes of pfcrt and pfmdr1 were also evaluated in persisting parasites. These data identify a possible threat to the parasitological efficacy of artemether-lumefantrine in West Africa, over a decade since it was first introduced on a large scale.
Assuntos
Antimaláricos , Malária Falciparum , Antimaláricos/uso terapêutico , Artemeter/uso terapêutico , Combinação Arteméter e Lumefantrina , Burkina Faso , Combinação de Medicamentos , Etanolaminas/uso terapêutico , Humanos , Malária Falciparum/tratamento farmacológico , Mali , Parasitemia/tratamento farmacológico , Plasmodium falciparum/genética , Falha de TratamentoRESUMO
Gut microbial dysbiosis has been shown to be an instrumental factor in severe acute malnutrition (SAM) and particularly, the absence of Methanobrevibacter smithii, a key player in energy harvest. Nevertheless, it remains unknown whether this absence reflects an immaturity or a loss of the microbiota. In order to assess that, we performed a case-control study in Mali using a propensity score weighting approach. The presence of M. smithii was tested using quantitative PCR on faeces collected from SAM children at inclusion and at discharge when possible or at day 15 for controls. M. smithii was highly significantly associated with the absence of SAM, detected in 40.9% controls but only in 4.2% cases (p < 0.0001). The predictive positive value for detection of M. smithii gradually increased with age in controls while decreasing in cases. Among children providing two samples with a negative first sample, no SAM children became positive, while this proportion was 2/4 in controls (p = 0.0015). This data suggests that gut dysbiosis in SAM is not an immaturity but rather features a loss of M. smithii. The addition of M. smithii as a probiotic may thus represent an important addition to therapeutic approaches to restore gut symbiosis.
Assuntos
Fezes/microbiologia , Microbioma Gastrointestinal , Methanobrevibacter , Desnutrição Aguda Grave/microbiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Disbiose/genética , Disbiose/microbiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mali , Methanobrevibacter/genética , Methanobrevibacter/crescimento & desenvolvimento , Desnutrição Aguda Grave/genéticaRESUMO
Strain Marseille-P2082, an anaerobic, non-motile, asporogenous, Gram-negative, coccoid bacterium was isolated from the faeces of a 33 year-old obese French woman before bariatric surgery. The isolate exhibits 98.65% 16S rRNA gene nucleotide sequence similarity with Negativicoccus succinicivorans strain ADV 07/08/06-B-1388T, its current closest phylogenetic neighbour with standing in nomenclature. However, the dDDH relatedness between the new isolate and N. succinicivorans type strain ADV 07/08/06-B-1388T is 52.5 ± 2.7%. Strain Marseille-P2082 has a genome of 1,360,589 bp with a 51.1% G+C content. Its major fatty acids were identified as C18:1n9, C18:0 and C16:0. Based on its phenotypic, genomic and phylogenetic characteristics, strain Marseille-P2082T [= CSURP2082 (Collection de Souches de l'Unité des Rickettsies) = DSM 100853] is proposed as the type strain of the novel species Negativicoccus massiliensis sp. nov. The 16S rRNA gene sequence and whole-genome shotgun sequence have been deposited in EMBL-EBI under accession numbers LN876651 and LT700188, respectively.
Assuntos
Microbioma Gastrointestinal , Obesidade , Filogenia , Veillonellaceae/classificação , Veillonellaceae/isolamento & purificação , Adulto , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Fezes/microbiologia , Feminino , Genes Bacterianos/genética , Genoma Bacteriano , Genômica , Humanos , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Veillonellaceae/genética , Veillonellaceae/fisiologiaRESUMO
Archaeal sequences have been detected in human colostrum and milk, but no studies have determined whether living archaea are present in either of these fluids. Methanogenic archaea are neglected since they are not detected by usual molecular and culture methods. By using improved DNA detection protocols and microbial culture techniques associated with antioxidants previously developed in our center, we investigated the presence of methanogenic archaea using culture and specific Methanobrevibacter smithii and Methanobrevibacter oralis real-time PCR in human colostrum and milk. M. smithii was isolated from 3 colostrum and 5 milk (day 10) samples. M. oralis was isolated from 1 milk sample. For 2 strains, the genome was sequenced, and the rhizome was similar to that of strains previously isolated from the human mouth and gut. M. smithii was detected in the colostrum or milk of 5/13 (38%) and 37/127 (29%) mothers by culture and qPCR, respectively. The different distribution of maternal body mass index according to the detection of M. smithii suggested an association with maternal metabolic phenotype. M. oralis was not detected by molecular methods. Our results suggest that breastfeeding may contribute to the vertical transmission of these microorganisms and may be essential to seed the infant's microbiota with these neglected critical commensals from the first hour of life.
Assuntos
Aleitamento Materno/efeitos adversos , Colostro/microbiologia , Methanobrevibacter/isolamento & purificação , Leite Humano/microbiologia , Animais , Índice de Massa Corporal , Crescimento Quimioautotrófico/genética , DNA Arqueal/genética , DNA Arqueal/isolamento & purificação , Euryarchaeota/genética , Euryarchaeota/patogenicidade , Fezes/microbiologia , Feminino , Humanos , Lactente , Methanobrevibacter/genética , Methanobrevibacter/patogenicidade , Microbiota/genética , Mães , GravidezRESUMO
Subsequent to the publication of the above article, it has been noticed that the designation of the type strain is not correct. The strain referred to throughout the article as strain AT7T should be designated as strain Marseille-P2086T (= CSUR P2086T = DSM 100837T). The corrected for protologue for the species Mediterraneibacter massiliensis, represented by strain Marseille-P2086T as type strain, is given below.
RESUMO
An anaerobic isolate, strain AT7T, was cultivated from a stool sample of a morbidly obese French woman using a microbial culturomics approach. The 16S rRNA gene sequence analysis showed that strain AT7T exhibited 96% nucleotide sequence similarity with Ruminococcus torques strain JCM 6553T (= ATCC 27756T = VPI B2-51T), currently the closest related species with a validly published name. The strain was observed to be a Gram-stain positive, non-motile, asporogenous and coccobacillary-shaped bacterium. It was found to be catalase positive and oxidase negative. Its major fatty acids were identified as C16:0 (54%) and C18:1n9 (30%). The draft genome of strain AT7T is 3,069,882 bp long with 42.4% G+C content. 2925 genes were predicted, including 2867 protein-coding genes and 58 RNAs. Based on phenotypic, biochemical, phylogenetic and genomic evidence, we propose the creation of the new genus Mediterraneibacter and species, Mediterraneibacter massiliensis, that contains strain AT7T (= CSUR P2086T = DSM 100837T), and the reclassification of Ruminococcus faecis, Ruminococcus lactaris, Ruminococcus torques, Ruminococcus gnavus, Clostridium glycyrrhizinilyticum as Mediterraneibacter faecis comb. nov., with type strain Eg2T (= KCTC 5757T = JCM15917T), Mediterraneibacter lactaris comb. nov., with type strain ATCC 29176T (= VPI X6-29T), Mediterraneibacter torques comb. nov., with type strain ATCC 27756T (= VPI B2-51T), Mediterraneibacter gnavus comb. nov., with type strain ATCC 29149T (= VPI C7-9T) and Mediterraneibacter glycyrrhizinilyticus comb. nov., with type strain ZM35T (= JCM 13368T = DSM 17593T), respectively.
Assuntos
Microbioma Gastrointestinal/genética , Ruminococcus/classificação , Ruminococcus/genética , Clostridium/classificação , Clostridium/genética , Humanos , Obesidade/microbiologia , Fenótipo , Filogenia , Análise de Sequência de DNARESUMO
The human gut is composed of a large diversity of microorganisms, which have been poorly described. Here, using culturomics, a new concept based on the variation in culture conditions and MALDI-TOF MS identification, we proceed to explore the microbial diversity of the complex ecosystem of the human gut. Using this approach, we isolated strain AT8T (=CSUR P2118 = DSM 101782) from stool specimens collected from a 51-year-old obese French woman. Strain AT8T is a strictly anaerobic, nonmotile, nonspore-forming gram-positive coccus that do not exhibit catalase and oxidase activities. 16S rDNA-based identification of strain AT8T demonstrated 92% gene sequence similarity with Eggerthella lenta DSM 2243, the phylogenetically closed validly named type species. Here, we present a set of features for the strain AT8T and the description of its complete genome sequence and annotation. The 2,091,845 bp long genome has a G+C content of 63.46% and encodes1,849 predicted genes; 1,781 were protein-coding genes, and 68 were RNAs. On the basis of the characteristics reported here, we propose the creation of a new bacterial genus Hugonella gen. nov., belonging to the Eggerthellaceae family and including Hugonella massiliensis gen. nov., sp. nov., strain AT8T as the type strain.
Assuntos
Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Trato Gastrointestinal/microbiologia , Sequenciamento Completo do Genoma , Actinobacteria/química , Actinobacteria/genética , Anaerobiose , Composição de Bases , Análise por Conglomerados , DNA Ribossômico/química , DNA Ribossômico/genética , Fezes/microbiologia , Feminino , França , Humanos , Pessoa de Meia-Idade , Anotação de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
An anaerobic bacterium, strain AT2T, was isolated from the fresh stool sample of a healthy French man using the culturomics approach. The 16S rRNA gene sequence analysis showed that strain AT2T had 95.2â% nucleotide sequence similarity with Gemmiger formicilisATCC 27749T, the phylogenetically closest species with standing in nomenclature. Cells are Gram-stain-negative, catalase- and oxidase-negative, obligately anaerobic, non-motile, non-spore-forming, rod-shaped, and the bacilli were mesothermophilic. The major fatty acids were C16â:â0 (43.8â%) and C18â:â1n9 (20â%). The DNA G+C content of the strain based on its genome sequence was 56.8 mol%. Based on the phenotypic, biochemical and phylogenetic analysis, we propose the creation of the genus Fournierella gen. nov., which contains strain AT2T (=CSUR P2014T=DSM 100451T) as the type strain of the type species Fournierella massiliensis gen. nov., sp. nov.