93 research outputs found
The gut microbiome and metabolome of two riparian communities in the Amazon
During the last decades it has become increasingly clear that the microbes that live on and in humans are critical for health. The communities they form, termed microbiomes, are involved in fundamental processes such as the maturation and constant regulation of the immune system. Additionally, they constitute a strong defense barrier to invading pathogens, and are also intricately linked to nutrition. The parameters that affect the establishment and maintenance of these microbial communities are diverse, and include the genetic background, mode of birth, nutrition, hygiene, and host lifestyle in general. Here, we describe the characterization of the gut microbiome of individuals living in the Amazon, and the comparison of these microbial communities to those found in individuals from an urban, industrialized setting. Our results showed striking differences in microbial communities from these two types of populations. Additionally, we used high-throughput metabolomics to study the chemical ecology of the gut environment and found significant metabolic changes between the two populations. Although we cannot point out a single cause for the microbial and metabolic changes observed between Amazonian and urban individuals, they are likely to include dietary differences as well as diverse patterns of environmental exposure. To our knowledge, this is the first description of gut microbial and metabolic profiles in Amazonian populations, and it provides a starting point for thorough characterizations of the impact of individual environmental conditions on the human microbiome and metabolome
Fighting HIV/AIDS in a developing country: lessons from a small cohort from the largest Brazilian city
Not Applicabl
The Intestinal Microbiota Plays a Role in Salmonella-Induced Colitis Independent of Pathogen Colonization
The intestinal microbiota is composed of hundreds of species of bacteria, fungi
and protozoa and is critical for numerous biological processes, such as nutrient
acquisition, vitamin production, and colonization resistance against bacterial
pathogens. We studied the role of the intestinal microbiota on host resistance
to Salmonella enterica serovar Typhimurium-induced colitis.
Using multiple antibiotic treatments in 129S1/SvImJ mice, we showed that
disruption of the intestinal microbiota alters host susceptibility to infection.
Although all antibiotic treatments caused similar increases in pathogen
colonization, the development of enterocolitis was seen only when streptomycin
or vancomycin was used; no significant pathology was observed with the use of
metronidazole. Interestingly, metronidazole-treated and infected C57BL/6 mice
developed severe pathology. We hypothesized that the intestinal microbiota
confers resistance to infectious colitis without affecting the ability of
S. Typhimurium to colonize the intestine. Indeed, different
antibiotic treatments caused distinct shifts in the intestinal microbiota prior
to infection. Through fluorescence in situ hybridization,
terminal restriction fragment length polymorphism, and real-time PCR, we showed
that there is a strong correlation between the intestinal microbiota composition
before infection and susceptibility to Salmonella-induced
colitis. Members of the Bacteroidetes phylum were present at significantly
higher levels in mice resistant to colitis. Further analysis revealed that
Porphyromonadaceae levels were also increased in these mice. Conversely, there
was a positive correlation between the abundance of
Lactobacillus sp. and predisposition to colitis. Our data
suggests that different members of the microbiota might be associated with
S. Typhimurium colonization and colitis. Dissecting the
mechanisms involved in resistance to infection and inflammation will be critical
for the development of therapeutic and preventative measures against enteric
pathogens
Supporting people with severe mental health conditions during the COVID-19 pandemic : considerations for low- and middle-income countries using telehealth case management
Efficacy of acupuncture and electroacupuncture in patients with nonspecific low back pain: study protocol for a randomized controlled trial
Eu virei homem!: a construção das masculinidades para adolescentes participantes de um projeto de promoção de saúde sexual e reprodutiva
Comparative Genomic Analysis of Human Fungal Pathogens Causing Paracoccidioidomycosis
Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasiliensis (Pb03 and Pb18) and one strain of Paracoccidioides lutzii (Pb01). These genomes range in size from 29.1 Mb to 32.9 Mb and encode 7,610 to 8,130 genes. To enable genetic studies, we mapped 94% of the P. brasiliensis Pb18 assembly onto five chromosomes. We characterized gene family content across Onygenales and related fungi, and within Paracoccidioides we found expansions of the fungal-specific kinase family FunK1. Additionally, the Onygenales have lost many genes involved in carbohydrate metabolism and fewer genes involved in protein metabolism, resulting in a higher ratio of proteases to carbohydrate active enzymes in the Onygenales than their relatives. To determine if gene content correlated with growth on different substrates, we screened the non-pathogenic onygenale Uncinocarpus reesii, which has orthologs for 91% of Paracoccidioides metabolic genes, for growth on 190 carbon sources. U. reesii showed growth on a limited range of carbohydrates, primarily basic plant sugars and cell wall components; this suggests that Onygenales, including dimorphic fungi, can degrade cellulosic plant material in the soil. In addition, U. reesii grew on gelatin and a wide range of dipeptides and amino acids, indicating a preference for proteinaceous growth substrates over carbohydrates, which may enable these fungi to also degrade animal biomass. These capabilities for degrading plant and animal substrates suggest a duality in lifestyle that could enable pathogenic species of Onygenales to transfer from soil to animal hosts.National Institute of Allergy and Infectious Diseases (U.S.)National Institutes of Health. Department of Health and Human Services (contract HHSN266200400001C)National Institutes of Health. Department of Health and Human Services(contract HHSN2722009000018C)Brazil. National Council for Scientific and Technological Developmen
- …