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1.
PLoS One ; 19(2): e0298458, 2024.
Article in English | MEDLINE | ID: mdl-38381750

ABSTRACT

Cutaneous leishmaniasis (CL) caused by Leishmania braziliensis, is a disease characterized by well-limited ulcerated lesions with raised borders in exposed parts of the body. miRNAs are recognized for their role in the complex and plastic interaction between host and pathogens, either as part of the host's strategy to neutralize infection or as a molecular mechanism employed by the pathogen to modulate host inflammatory pathways to remain undetected. The mir155 targets a broad range of inflammatory mediators, following toll-like receptors (TLRs) signaling. In this work, we evaluated the effects of the expression of miR155a-5p in human macrophages infected with L. braziliensis. Our results show that miR155a-5p is inversely correlated with early apoptosis and conversely, seems to influence an increment in the oxidative burst in these cells. Altogether, we spotted a functional role of the miR155a-5p in CL pathogenesis, raising the hypothesis that an increased miR-155 expression by TLR ligands influences cellular mechanisms settled to promote both killing and control of parasite density after infection.


Subject(s)
Leishmania braziliensis , Leishmaniasis, Cutaneous , MicroRNAs , Humans , Leishmania braziliensis/physiology , Reactive Oxygen Species/metabolism , Macrophages/metabolism , Leishmaniasis, Cutaneous/parasitology , MicroRNAs/genetics , Apoptosis/genetics
2.
Front Immunol ; 14: 1280949, 2023.
Article in English | MEDLINE | ID: mdl-38143766

ABSTRACT

Background: Leishmaniasis is an infectious disease caused by protozoa of the genus Leishmania. There are still no vaccines, and therapeutic options are limited, indicating the constant need to understand the fine mechanisms of its pathophysiology. An approach that has been explored in leishmaniasis is the participation of microRNAs (miRNAs), a class of small non-coding RNAs that act, in most cases, to repress gene expression. miRNAs play a role in the complex and plastic interaction between the host and pathogens, either as part of the host's immune response to neutralize infection or as a molecular strategy employed by the pathogen to modulate host pathways to its own benefit. Methods: Monocyte-derived macrophages from healthy subjects were infected with isolates of three clinical forms of L. braziliensis: cutaneous (CL), mucosal (ML), and disseminated (DL) leishmaniasis. We compared the expression of miRNAs that take part in the TLR/NFkB pathways. Correlations with parasite load as well as immune parameters were analyzed. Results: miRNAs -103a-3p, -21-3p, 125a-3p -155-5p, -146a-5p, -132- 5p, and -147a were differentially expressed in the metastatic ML and DL forms, and there was a direct correlation between miRNAs -103a-3p, -21-3p, -155-5p, -146a-5p, -132-5p, and -9-3p and parasite load with ML and DL isolates. We also found a correlation between the expression of miR-21-3p and miR-146a-5p with the antiapoptotic gene BCL2 and the increase of viable cells, whereas miR-147a was indirectly correlated with CXCL-9 levels. Conclusion: The expression of miRNAs is strongly correlated with the parasite load and the inflammatory response, suggesting the participation of these molecules in the pathogenesis of the different clinical forms of L. braziliensis.


Subject(s)
Leishmania , Leishmaniasis, Cutaneous , MicroRNAs , Humans , United States , MicroRNAs/genetics , MicroRNAs/metabolism , Macrophages/metabolism , Skin
3.
Front Cell Infect Microbiol ; 12: 772829, 2022.
Article in English | MEDLINE | ID: mdl-35795189

ABSTRACT

Since its emergence in the beginning of the 90's, multidrug-resistant (MDR) Salmonella enterica subsp. enterica serovar Kentucky has become a significant public health problem, especially in East Africa. This study aimed to investigate the antimicrobial resistance profile and the genotypic relatedness of Salmonella Kentucky isolated from animal sources in Ethiopia and Kenya (n=19). We also investigated population evolutionary dynamics through phylogenetic and pangenome analyses with additional publicly available Salmonella Kentucky ST198 genomes (n=229). All the 19 sequenced Salmonella Kentucky isolates were identified as ST198. Among these isolates, the predominant genotypic antimicrobial resistance profile observed in ten (59.7%) isolates included the aac(3)-Id, aadA7, strA-strB, blaTEM-1B, sul1, and tet(A) genes, which mediated resistance to gentamicin, streptomycin/spectinomycin, streptomycin, ampicillin, sulfamethoxazole and tetracycline, respectively; and gyrA and parC mutations associated to ciprofloxacin resistance. Four isolates harbored plasmid types Incl1 and/or Col8282; two of them carried both plasmids. Salmonella Pathogenicity islands (SPI-1 to SPI-5) were highly conserved in the 19 sequenced Salmonella Kentucky isolates. Moreover, at least one Pathogenicity Island (SPI 1-4, SPI 9 or C63PI) was identified among the 229 public Salmonella Kentucky genomes. The phylogenetic analysis revealed that almost all Salmonella Kentucky ST198 isolates (17/19) stemmed from a single strain that has accumulated ciprofloxacin resistance-mediating mutations. A total of 8,104 different genes were identified in a heterogenic and still open Salmonella Kentucky ST198 pangenome. Considering the virulence factors and antimicrobial resistance genes detected in Salmonella Kentucky, the implications of this pathogen to public health and the epidemiological drivers for its dissemination must be investigated.


Subject(s)
Salmonella enterica , Animals , Anti-Bacterial Agents/pharmacology , Ciprofloxacin , Drug Resistance, Multiple, Bacterial/genetics , Genomics , Kentucky , Livestock , Phylogeny , Salmonella enterica/genetics , Serogroup , Streptomycin
4.
Front Microbiol ; 13: 802625, 2022.
Article in English | MEDLINE | ID: mdl-35722289

ABSTRACT

The increasing number of studies reporting the presence of Salmonella in environmental water sources suggests that it is beyond incidental findings originated from sparse fecal contamination events. However, there is no consensus on the occurrence of Salmonella as its relative serovar representation across non-recycled water sources. We conducted a meta-analysis of proportions by fitting a random-effects model using the restricted maximum-likelihood estimator to obtain the weighted average proportion and between-study variance associated with the occurrence of Salmonella in water sources. Moreover, meta-regression and non-parametric supervised machine learning method were performed to predict the effect of moderators on the frequency of Salmonella in non-recycled water sources. Three sequential steps (identification of information sources, screening and eligibility) were performed to obtain a preliminary selection from identified abstracts and article titles. Questions related to the frequency of Salmonella in aquatic environments, as well as putative differences in the relative frequencies of the reported Salmonella serovars and the role of potential variable moderators (sample source, country, and sample volume) were formulated according to the population, intervention, comparison, and outcome method (PICO). The results were reported according to the Preferred Reporting Items for Systematic Review and Meta-Analyzes statement (PRISMA). A total of 26 eligible papers reporting 148 different Salmonella serovars were retrieved. According to our model, the Salmonella frequency in non-recycled water sources was 0.19 [CI: 0.14; 0.25]. The source of water was identified as the most import variable affecting the frequency of Salmonella, estimated as 0.31 and 0.17% for surface and groundwater, respectively. There was a higher frequency of Salmonella in countries with lower human development index (HDI). Small volume samples of surface water resulted in lower detectable Salmonella frequencies both in high and low HDI regions. Relative frequencies of the 148 serovars were significantly affected only by HDI and volume. Considering that serovars representation can also be affected by water sample volume, efforts toward the standardization of water samplings for monitoring purposes should be considered. Further approaches such as metagenomics could provide more comprehensive insights about the microbial ecology of fresh water and its importance for the quality and safety of agricultural products.

5.
Rev. baiana saúde pública ; 23(1/4): 7-20, dez. 1998-jan. 1999. tab, graf
Article in Portuguese | LILACS | ID: lil-284611

ABSTRACT

Foi realizado estudo para caracterizar a situaçäo da hipertensäo arterial na populaçäo do bairro de Alto das Pombas, em Salvador. Aferiu-se a pressäo aretrial (PA) de 491 indivíduos acima de 20 anos de idade, numa amostra de domicílios do bairro, em agosto de 1996. Foram considerados hipertensos os adultos que apresentaram PA sistólica igual ou superior a 140mmHg e/ou diastólica igual ou superior a 90mmHg, acrescidos daqueles indivíduos que informaram serem portadores dadoença. Obteve-se uma prevalência de hipertensäo de 41,1 porcento, mais elevada no sexo feminino e na faixa de 50 e mais anos. Chamou a atençäo, o alto percentual de indivíduos hipertensos com PA näo controlada, no momento da pesquisa. Os hipertensos foram revisitados após três meses, quando se detectou que 68 porcento continuavam com os níveis pressóricos elevados. Foi referido pelos hipertensos, maior grau de adesäo à reduçäo do sal na dieta e ao tratamento medicamentoso, em relaçäo a outras medidas de controle. O uso de medicamentos näo se mostrou efetivo no controle da doença, sugerindo irregularidades e inadequaçöes no seu uso. Concluiu-se que a hipertensäo arterial constitui-se num problema de saúde pública relevante na área, o qual requer intervençäo através de açöes educativas e organizaçäo da assistência.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Hypertension/complications , Hypertension/epidemiology , Hypertension/prevention & control , Health Surveys , Patient Education as Topic , Prevalence , Community Health Services/organization & administration , Communitarian Organization , Cross-Sectional Studies , Blood Pressure Determination/methods , Interviews as Topic
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