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1.
Cad. Ibero Am. Direito Sanit. (Impr.) ; 13(1): 119-130, jan.-mar.2024.
Artigo em Português | LILACS | ID: biblio-1538393

RESUMO

Objetivo: o presente estudo se destina a compreender a percepção das mulheres que fazem sexo com mulheres, referente ao cuidado que recebem nos serviços de saúde, no âmbito de sua saúde sexual e reprodutiva, a fim de verificar se o atendimento ofertado atende a integralidade de seu direito à saúde e, também, evidenciar o papel dos profissionais de saúde na garantia desses direitos. Metodologia: foi realizada revisão de literatura nacional para elaboração do instrumento de coleta de dados e pesquisa qualiquantitativa através de formulário e entrevista individual via internet. Resultados: Foram obtidas 287 respostas, as falas revelaram as seguintes categorias: A- Violência física sofrida em serviços de saúde, B- Negligência e falta de acolhimento em consultas ginecológicas e em serviços de saúde, C- Presunção da heterossexualidade nos serviços de saúde, D- Invisibilidade e violência moral e psicológica. Conclusão: evidenciou-se que mulheres que fazem sexo com mulheres ainda sofrem uma série de discriminações e violências nos serviços de saúde, ao buscarem cuidados integrais, principalmente no que tange aos seus direitos sexuais e reprodutivos.


Objective: this study is intended to understand the perception of women who have sex with women, regarding the care they receive in health services, within the scope of their sexual and reproductive health, in order to verify whether the care offered to them meets the integrality of their right to health and, also, highlight the role of health professionals in guaranteeing these rights. Methodology: A national literature review was carried out for the elaboration of the data collection instrument and qualitative and quantitative research through an individual form and individual interview via the internet. Results: 287 responses were obtained, the statements revealed the following categories: A- Physical violence suffered in health services, B- Negligence and lack of acceptance in gynecological consultations and health services, C- Presumption of heterosexuality in health services, D- Invisibility and, moral and psychological violence. Conclusion: it was evident that women who have sex with women still suffer a series of discrimination and violence in health services, when seeking comprehensive care, especially with regard to their sexual and reproductive rights.


Objetivo: este estudio tiene como finalidad conocer la percepción de las mujeres que tienen sexo con mujeres, respecto a la atención que reciben en los servicios de salud, en el ámbito de su salud sexual y reproductiva, con el fin de verificar si la atención que se les brinda cumple con la integralidad de su derecho a la salud y, además, destacar el papel de los profesionales de la salud en la garantía de estos derechos. Metodología: se realizó una revisión de literatura nacional para la elaboración del instrumento de recolección de datos e investigación cualitativa y cuantitativa a través de formulario individual y entrevista individual vía internet. Resultados: se obtuvieron 287 respuestas, los enunciados revelaron las siguientes categorías: A- Violencia física sufrida en los servicios de salud, B- Negligencia y falta de aceptación en las consultas ginecológicas y servicios de salud, C- Presunción de heterosexualidad en los servicios de salud, D- Invisibilidad y violencia moral y psicológica. Conclusión: se evidenció que las mujeres que tienen sexo con mujeres aún sufren una serie de discriminaciones y violencias en los servicios de salud, al momento de buscar atención integral, especialmente en lo que se refiere a sus derechos sexuales y reproductivos.


Assuntos
Direito Sanitário
2.
Chemosphere ; 352: 141348, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340998

RESUMO

The Amazon region abounds in precious mineral resources including gold, copper, iron, and coltan. Artisanal and small-scale gold mining (ASGM) poses a severe risk in this area due to considerable mercury release into the surrounding ecosystems. Nonetheless, the impact of mercury on both the overall microbiota and the microbial populations involved in mercury transformation is not well understood. In this study we evaluated microbial diversity in samples of soil, sediment and water potentially associated with mercury contamination in two localities (Taraira and Tarapacá) in the Colombian Amazon Forest. To this end, we characterized the bacterial community structure and mercury-related functions in samples from sites with a chronic history of mercury contamination which today have different levels of total mercury content. We also determined mercury bioavailability and mobility in the samples with the highest THg and MeHg levels (up to 43.34 and 0.049 mg kg-1, respectively, in Taraira). Our analysis of mercury speciation showed that the immobile form of mercury predominated in soils and sediments, probably rendering it unavailable to microorganisms. Despite its long-term presence, mercury did not appear to alter the microbial community structure or composition, which was primarily shaped by environmental and physicochemical factors. However, an increase in the relative abundance of merA genes was detected in polluted sediments from Taraira. Several Hg-responsive taxa in soil and sediments were detected in sites with high levels of THg, including members of the Proteobacteria, Acidobacteria, Actinobacteria, Firmicutes and Chloroflexi phyla. The results suggest that mercury contamination at the two locations sampled may select mercury-adapted bacteria carrying the merA gene that could be used in bioremediation processes for the region.


Assuntos
Ecossistema , Mercúrio , Água/análise , Ouro/análise , Solo/química , Colômbia , Mercúrio/análise , Bactérias/genética , Mineração , Monitoramento Ambiental/métodos
3.
Innate Immun ; 29(5): 71-82, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37350049

RESUMO

Killer cell immunoglobulin-like receptors (KIR) exhibit extensive diversity, giving rise to different KIR profiles in populations worldwide. This study aimed to investigate the distribution of KIR genes and HLA ligands in a population from Campinas, southeastern Brazil (n = 292), and to compare their results with other populations. A comprehensive analysis of population-specific genes, genotype, and haplotype frequencies of KIR may facilitate a better understanding of their evolution and role in immunity. The genotyping of 16 KIR genes and HLA class I alleles was performed by the reverse sequence-specific oligonucleotide methodology using the Luminex platform (One Lambda, Inc., Canoga Park, CA). The framework genes were present in all individuals, with the most common non-framework KIR genes detected being KIR2DP1(96.6%), KIR2DL1(95.5%), KIR3DL1(94.5%), KIR2DS4(93.8%) and KIR2DL3(87.3%). KIR2DS1, KIR2DS3, KIR2DS5, and KIR3DS1 presented frequencies below 40%. KIR2DL2, KIR2DL5, and KIR2DS2 showed intermediate frequencies (between53% and 58%). The activating gene KIR2DS5 was the least common in this population (30.8%). Forty-five KIR profiles were found with the commonest being the homozygous A haplotype (27.4%). The distribution of KIR genes in the Brazilian population is similar to Caucasian European and Euro-descendant populations.


Assuntos
Receptores KIR , Humanos , Brasil , Frequência do Gene , Ligantes , Receptores KIR/genética , Genótipo
4.
FEBS J ; 289(23): 7582-7604, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35816183

RESUMO

In the strictly anaerobic nitrate reducing bacterium Aromatoleum anaerobium, degradation of 1,3-dihydroxybenzene (1,3-DHB, resorcinol) is controlled by two bacterial enhancer-binding proteins (bEBPs), RedR1 and RedR2, which regulate the transcription of three σ54 -dependent promoters controlling expression of the pathway. RedR1 and RedR2 are identical over their length except for their N-terminal tail which differ in sequence and length (six and eight residues, respectively), a single change in their N-terminal domain (NTD), and nine non-identical residues in their C-terminal domain (CTD). Their NTD is composed of a GAF and a PAS domain connected by a linker helix. We show that each regulator is controlled by a different mechanism: whilst RedR1 responds to the classical NTD-mediated negative regulation that is released by the presence of its effector, RedR2 activity is constitutive and controlled through interaction with BtdS, an integral membrane subunit of hydroxyhydroquinone dehydrogenase carrying out the second step in 1,3-DHB degradation. BtdS sequesters the RedR2 regulator to the membrane through its NTD, where a four-Ile track in the PAS domain, interrupted by a Thr in RedR1, and the N-terminal tail are involved. The presence of 1,3-DHB, which is metabolized to hydroxybenzoquinone, releases RedR2 from the membrane. Most bEBPs assemble into homohexamers to activate transcription; we show that hetero-oligomer formation between RedR1 and RedR2 is favoured over homo-oligomers. However, either an NTD-truncated version of RedR1 or a full-length RedR2 are capable of promoter activation on their own, suggesting they should assemble into homohexamers in vivo. We show that promoter DNA behaves as an allosteric effector through binding the CTD to control ΔNTD-RedR1 multimerization and activity. Overall, the regulation of the 1,3-DHB anaerobic degradation pathway can be described as a novel mode of bEBP activation and assembly.

5.
Appl Microbiol Biotechnol ; 106(7): 2775-2793, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35344092

RESUMO

Two sites of the Colombian Amazon region with different levels of human intervention and mercury pollution were selected for the collection of samples of river and lake water, sediments, and associated forest soils. The Tarapacá region, affected mainly by barrage mining, showed low mercury concentrations, whilst in the Taraira region, affected by underground mining, there were several points with high mercury pollution levels. A collection of 72 bacterial and 10 yeast strains with different levels of mercury resistance was isolated and characterized. Most of the highly resistant bacterial strains (MIC > 40 mg L-1 HgCl2) were isolated from soil and sediment samples and belonged to either Pseudomonas (60%) or Bacillus (20%). Most of highly resistant bacterial strains were positive for the presence of the merA gene, suggesting an active mercury resistance mechanism. This was confirmed in the two most resistant strains, Pseudomonas sp. TP30 and Burkholderia contaminans TR100 (MIC = 64 and 71 mg L-1 HgCl2, respectively), which in the presence of increasing mercury concentrations expressed the merA gene at increasing levels, concomitant with a significant mercury reduction activity. Analysis of the MerA sequences present in the different isolates suggested a high gene conservation within the taxonomic groups but also several horizontal gene transfer events between taxonomically distant genera. We also observed a positive correspondence between the presence of the merA gene and the number of antibiotics to which the strains were resistant to. The most resistant strains are good candidates for future applications in the bioremediation of mercury-contaminated sites in the Amazon.Key points• Amazon sediments affected by underground gold mining have higher Hg levels.• Highly Hg-resistant isolates belonged to Pseudomonas and Bacillus genera.• TR100 and TP30 strains showed remediation potential to be used in the Amazon region.


Assuntos
Mercúrio , Bactérias/genética , Colômbia , Ecossistema , Ouro , Humanos , Mercúrio/análise , Mineração , Solo
7.
HLA ; 96(6): 744-745, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33043627

RESUMO

Two novel HLA alleles DRB1*11:261 and DRB1*13:286 have nonsynonymous mutations in exon 2.


Assuntos
Cadeias HLA-DRB1 , Alelos , Brasil , Éxons/genética , Cadeias HLA-DRB1/genética , Humanos
8.
J Nutr Biochem ; 86: 108494, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32920089

RESUMO

Overfeeding and rapid weight gain during early life are risk factors for the development of obesity in adulthood. This metabolic malprogramming may be mediated by endocrine disturbances during critical periods of development. Cholecystokinin (CCK) acts on the central nervous system by elevating thermogenesis and the activity of anorectic neurons, modulating overall energy balance. Therefore, we tested the hypothesis that postnatal overfeeding impaired CCK effects. Pups were raised in either a litter of three (neonatal overnutrition/small litter group) or 12 (controls/normal litter group) pups per dam to study the effects of postnatal overfeeding on the central and peripheral CCK systems in adulthood. Rats raised in small litters became overweight during lactation and remained overweight as adults, with increased adiposity and plasma levels of lipids, glucose, insulin, and leptin. Neonatally over-nourished rats showed attenuation of gastric emptying and anorexigenic response to CCK, suggesting that offspring from the SL group may present CCK resistance as adult male rats. Consistent with this idea, overweight rats displayed impaired central response in c-Fos immunoreactivity on the nucleus tractus solitarius, area postrema, paraventricular nucleus, central amygdala, arcuate nucleus, and dorsomedial hypothalamus in response to peripheral CCK at adulthood. The small litter group of adult male rats also exhibited reduced norepinephrine- and CCK-stimulated thermogenesis. Unresponsiveness to the effects of CCK may contribute to overweight and metabolic dysfunctions observed in postnatally over-nourished adult rats. Thus, the involvement of an impaired CCK system, among other neurohormonal failures, may contribute to the development of obesity.


Assuntos
Adiposidade , Sistema Nervoso Central/fisiopatologia , Colecistocinina/metabolismo , Sistema Endócrino/fisiopatologia , Hipernutrição/fisiopatologia , Tecido Adiposo/metabolismo , Animais , Animais Recém-Nascidos , Mapeamento Encefálico , Metabolismo Energético , Feminino , Esvaziamento Gástrico , Glucose/metabolismo , Homeostase , Hipotálamo , Leptina/sangue , Lipídeos/química , Masculino , Obesidade/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Wistar , Termogênese , Aumento de Peso
9.
Cad. Ibero Am. Direito Sanit. (Impr.) ; 9(1): 97-119, jan.-mar.2020.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1087840

RESUMO

Introdução: a violência obstétrica vem sendo entendida como toda violência física, moral, patrimonial ou psicológica praticada contra as mulheres no momento do parto, pós-parto e puerpério, sendo constatada em diversas práticas que ocorrem nos sistemas de saúde, tanto público quanto privado. Objetivo: busca aproximar o direito sanitário das questões relacionadas à garantia dos direitos sexuais e reprodutivos das mulheres, como parte indissociável do direito à saúde, abordando o conceito de violência obstétrica e as proposições legislativas que tramitam no Congresso Nacional brasileiro sobre o tema. Metodologia: utilizou-se de pesquisa bibliográfica e documental, utilizando o descritor violência obstétrica nos sítios de busca. Resultados: foram identificadas 11 proposições legislativas sobre o tema, das quais 10 fizeram parte do presente estudo; também foram abordados o conceito e os principais posicionamentos políticos e sociais sobre a violência obstétrica. Conclusões: o número de proposições legislativas no parlamento brasileiro sinalizam sobre a necessidade da disciplina jurídica do tema, entendendo-o de forma ampla, conforme posicionamento dos movimentos sociais em prol dos direitos das mulheres, e que a disciplina jurídica do tema se revela necessária para dirimir divergências acerca da aplicação do termo violência obstétrica e suas repercussões na prática médica e nos serviços de saúde no Brasil, tendo em vista a proteção ao direito sexual e reprodutivo das mulheres.


Introduction: obstetric violence has been understood as any physical, moral, patrimonial or psychological violence practiced against women at delivery, postpartum and puerperium, that is verified in several practices that occur in health systems, both public and private. Objective: this article seeks to bring health law closer to issues related to the guarantee of sexual and reproductive rights, as an inseparable part of the right to health, approaching the concept of obstetric violence and the legislative proposals that are being processed in the Brazilian National Congress on the subject. Methodology: bibliographic and documentary research was used, using the descriptor obstetric violence on search sites. Results: eleven legislative proposals on the topic were identified, of which 10 were part of the present study, as well as the concept outlined on the topic and the main political and social positions on the subject were addressed. Conclusions: it is concluded that the largest number of legislative proposals in the brasilian parliament demonstrates the need for legal discipline on the topic, understanding it broadly, according to the position of social movements in favor of women's rights, and that the legal discipline of the theme is necessary to resolve differences over the application of the term obstetric violence and its repercussions in medical practice and in health services in Brazil, with a view to protecting women's sexual and reproductive rights.


Introducción: La violencia obstétrica se entiende como cualquier violencia física, moral, patrimonial o psicológica practicada contra las mujeres en el momento del parto, el posparto y el puerpério, siendo verificado en varias prácticas que ocurren en los sistemas de salud, tanto públicos como privados. Objetivo: Este artículo busca acercar los derechos de salud a cuestiones relacionadas con la garantía de los derechos sexuales y reproductivos de las mujeres, como parte inseparable del derecho a la salud, como parte inseparable del derecho a la salud, abordando el concepto de violencia obstétrica y las propuestas legislativas que se están procesando en el Congreso Nacional de Brasil sobre el tema. Metodología: Se utilizó investigación bibliográfica y documental, utilizando el descriptor de violencia obstétrica en los sitios de búsqueda. Resultados: Se identificaron once propuestas legislativas sobre el tema, de las cuales 10 fueron parte del presente estudio, así como el concepto que se ha esbozado sobre el tema y se abordaron las principales posiciones políticas y sociales sobre el tema. Conclusiones: Se concluye que el número de propuestas legislativas en el parlamento brasilero indica la necesidad de disciplina legal sobre el tema, entendiéndolo ampliamente, de acuerdo con la posición de los movimientos sociales a favor de los derechos de las mujeres, y que la disciplina legal del tema es necesaria para resolver las diferencias sobre la aplicación del término violencia obstétrica y sus repercusiones en la práctica médica y los servicios de salud en Brasil, con miras a proteger los derechos sexuales y reproductivos de las mujeres.

10.
Zoonoses Public Health ; 67(5): 587-590, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32034877

RESUMO

We report a Brucella outbreak with seven cases in the Northern Region of Portugal in 2018-2019, associated with the consumption of fresh cheese. This outbreak has implications for risk assessment in Portuguese migrants related to this area, and it is an example of cooperation between public institutions, in a One Health based approach.


Assuntos
Brucella/isolamento & purificação , Brucelose/epidemiologia , Brucelose/microbiologia , Queijo/microbiologia , Animais , Surtos de Doenças , Feminino , Microbiologia de Alimentos , Cabras , Humanos , Pessoa de Meia-Idade , Portugal/epidemiologia , Fatores de Risco , Zoonoses/epidemiologia , Zoonoses/microbiologia
11.
Pediatr Diabetes ; 21(4): 606-614, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32078220

RESUMO

OBJECTIVE: Characterization of partial remission using the insulin dose-adjusted HbA1c (IDAA1c) ≤ 9 definition in a multiethnic Brazilian population of children and adolescents with type 1 diabetes (T1D), in addition with the determination of both Class II HLA genotype and autoantibodies. METHODS: We analyzed the prevalence of partial remission in 51 new-onset T1D patients with a median time follow-up of 13 months from diagnosis. For this study, anti-GAD65, anti-IA2 and HLA class II genotyping were considered. RESULTS: Partial remission occurred in 41.2% of T1D patients until 3 months after diagnosis, mainly in those aged 5-15 years. We have demonstrated a significant increase in the haplotypes of class II HLA DRB1*0301-DQB1*0201 in children and adolescents with a partial remission phase of the disease (42.9% vs 21.7% in non-remitters, P = .0291). This haplotype was also associated with the reduction of anti-IA2 antibodies production. Homozygote DRB1*03-DQB1*0201/DRB1*03-DQB1*0201 children had the lowest prevalence of IA-2A antibodies (P = .0402). However, this association does not correlate with the time of the remission phase. CONCLUSION: Although the number of patients studied was reduced, our data suggested that the association between genetics and decrease in antibody production to certain islet auto-antigen may contribute, at least in part, to the remission phase of T1D.


Assuntos
Autoanticorpos/biossíntese , Diabetes Mellitus Tipo 1 , Antígenos de Histocompatibilidade Classe II/genética , Adolescente , Adulto , Autoanticorpos/genética , Brasil/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Antígenos HLA-DQ/genética , Cadeias HLA-DRB1/genética , Haplótipos , Humanos , Lactente , Masculino , Remissão Espontânea , Adulto Jovem
12.
J Immunol Res ; 2019: 2137538, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31886296

RESUMO

The purpose of this study was to assess the influence of single-nucleotide polymorphisms (SNPs) on cytokine genes in the development of diffuse large B-cell lymphoma (DLBCL). One hundred and twelve patients and 221 controls were investigated. Among them, 97 patients treated with R-CHOP were subdivided into two groups: (i) complete remission of the disease and (ii) patients who progressed to death, relapsed, or had disease progression. The SNPs investigated by PCR-SSP were TNF -308G>A (rs1800629), IFNG +874A>T (rs2430561), IL6 -174G>C (rs1800795), IL10 -1082A>G (rs1800896), IL10 -819C>T (rs1800871), IL10 -592C>A (rs1800872), and TGFB1 codon10T>C (rs1982073) and codon25G>C (rs1800471). In general, the genotypes that have been associated in the literature with lower production or intermediate production of IL-10 and higher production of IFN-γ were associated with the protection of the development of the disease, possibly favoring the Th1 immune response and diminishing the capacity of cell proliferation. However, patients receiving R-CHOP treatment presented unfavorable prognoses in the presence of genotypes related to the intermediate production of IL-10 and high production of TGF-ß1, indicating that cytokines may be related to the response to treatment and action mechanisms of Rituximab.


Assuntos
Predisposição Genética para Doença , Haplótipos , Interferon gama/genética , Interleucina-10/genética , Linfoma Difuso de Grandes Células B/genética , Polimorfismo de Nucleotídeo Único , Idoso , Alelos , Protocolos de Quimioterapia Combinada Antineoplásica , Estudos de Casos e Controles , Ciclofosfamida , Doxorrubicina , Feminino , Frequência do Gene , Estudos de Associação Genética , Humanos , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Razão de Chances , Prednisona , Prognóstico , Rituximab , Resultado do Tratamento , Vincristina
13.
Front Pharmacol ; 10: 1103, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31611793

RESUMO

Background: Mounting evidence indicate that reducing the sinoatrial node (SAN) activity may be a useful therapeutic strategy to control of heart failure. Purines, like ATP and its metabolite adenosine, consistently reduce the SAN spontaneous activity leading to negative cardiac chronotropy, with variable effects on the force of myocardial contraction (inotropy). Apart from adenosine A1 receptors, the human SAN expresses high levels of ATP-sensitive ionotropic P2X4 receptors (P2X4R), yet their cardiac role is unexplored. Methods: Here, we investigated the activity of P2 purinoceptors on isolated spontaneously beating atria (chronotropy) and on 2 Hz-paced right ventricular (RV, inotropy) strips from Wistar rats. Results: ATP (pEC 50 = 4.05) and its stable analogue ATPγS (pEC 50 = 4.69) concentration-dependently reduced atrial chronotropy. Inhibition of ATP breakdown into adenosine by NTPDases with POM-1 failed to modify ATP-induced negative chronotropy. The effect of ATP on atrial rate was attenuated by a broad-spectrum P2 antagonist, PPADS, as well as by 5-BDBD, which selectively blocks the P2X4R subtype; however, no effect was observed upon blocking the A1 receptor with DPCPX. The P2X4R positive allosteric modulator, ivermectin, increased the negative chronotropic response of ATP. Likewise, CTP, a P2X agonist that does not generate adenosine, replicated the P2X4R-mediated negative chronotropism of ATP. Inhibition of the Na+/Ca2+ exchanger (NCX) with KB-R7943 and ORM-10103, but not blockage of the HCN channel with ZD7288, mimicked the effect of the P2X4R blocker, 5-BDBD. In paced RV strips, ATP caused a mild negative inotropic effect, which magnitude was 2 to 3-fold increased by 5-BDBD and KB-R7943. Immunofluorescence confocal microscopy studies confirm that cardiomyocytes of the rat SAN and RV co-express P2X4R and NCX1 proteins. Conclusions: Data suggest that activation of ATP-sensitive P2X4R slows down heart rate by reducing the SAN activity while increasing the magnitude of ventricular contractions. The mechanism underlying the dual effect of ATP in the heart may involve inhibition of intracellular Ca2+-extrusion by bolstering NCX function in the reverse mode. Thus, targeting the P2X4R activation may create novel well-tolerated heart-rate lowering drugs with potential benefits in patients with deteriorated ventricular function.

14.
Microb Biotechnol ; 12(4): 662-676, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31087504

RESUMO

Polycyclic aromatic compounds (PAHs) are toxic compounds that are released in the environment as a consequence of industrial activities. The restoration of PAH-polluted sites considers the use of bacteria capable of degrading aromatic compounds to carbon dioxide and water. Here we characterize a new Xanthobacteraceae strain, Starkeya sp. strain N1B, previously isolated during enrichment under microaerophilic conditions, which is capable of using naphthalene crystals as the sole carbon source. The strain produced a structured biofilm when grown on naphthalene crystals, which had the shape of a half-sphere organized over the crystal. Scanning electron microscopy (SEM) and GC-MS analysis indicated that the biofilm was essentially made of cellulose, composed of several micron-long nanofibrils of 60 nm diameter. A cellulosic biofilm was also formed when the cells grew with glucose as the carbon source. Fourier transformed infrared spectroscopy (FTIR) confirmed that the polymer was type I cellulose in both cases, although the crystallinity of the material greatly depended on the carbon source used for growth. Using genome mining and mutant analysis, we identified the genetic complements required for the transformation of naphthalene into cellulose, which seemed to have been successively acquired through horizontal gene transfer. The capacity to develop the biofilm around the crystal was found to be dispensable for growth when naphthalene was used as the carbon source, suggesting that the function of this structure is more intricate than initially thought. This is the first example of the use of toxic aromatic hydrocarbons as the carbon source for bacterial cellulose production. Application of this capacity would allow the remediation of a PAH into such a value-added polymer with multiple biotechnological usages.


Assuntos
Alphaproteobacteria/metabolismo , Celulose/metabolismo , Nanoestruturas , Naftalenos/metabolismo , Alphaproteobacteria/crescimento & desenvolvimento , Carbono/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Microbiologia Industrial/métodos , Microscopia Eletrônica de Varredura
15.
Environ Microbiol Rep ; 11(4): 525-537, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30884168

RESUMO

The nitrate-reducing betaproteobacteria Azoarcus anaerobius and Thauera aromatica AR-1 use an oxidative mechanism to anaerobically degrade resorcinol and 3,5-dihydroxybenzoate (3,5-DHB), respectively, rendering hydroxyhydroquinone as intermediate. The first pathway step is performed by a dimethylsulphoxide-reductase family hydroxylase. The gene cluster coding for the pathway is homologous in these strains. Only these two Rhodocyclales are known to follow this anaerobic pathway, and nothing is known about its distribution in prokaryotes. To determine the relevance and diversity of this strategy in nature, we enriched for bacteria able to oxidize resorcinol or 3,5-DHB under denitrifying conditions. Nitrate-reducing bacteria able to degrade these compounds were present in soil, aquifer and marine sediments. We were able to isolate a number of strains with this capacity from soil and aquifer samples. Amplicon libraries of rehL, the gene encoding the first step of this pathway, showed an overall low diversity, most sequences clustering with either pathway enzyme. Isolates belonging to the Beta- and Gammaproteobacteria able to grow on these substrates revealed rehL homologues only in strains belonging to Thauera and Azoarcus. Analysis of sequenced genomes in the databases detected the presence of highly similar clusters in two additional betaproteobacteria and in the gammaproteobacterium Sedimenticola selenatireducens, although anaerobic growth on a dihydroxyaromatic could only be confirmed in Thauera chlorobenzoica 3CB-1. The presence of mobile elements in the flanking sequences of some of the clusters suggested events of horizontal gene transfer, probably contributing to expand the pathway to a broader host range within the Proteobacteria.


Assuntos
Betaproteobacteria/isolamento & purificação , Betaproteobacteria/metabolismo , Hidroquinonas/metabolismo , Redes e Vias Metabólicas/genética , Nitratos/metabolismo , Anaerobiose , Proteínas de Bactérias/genética , Betaproteobacteria/classificação , Betaproteobacteria/genética , Microbiologia Ambiental , Variação Genética , Genoma Bacteriano/genética , Hidroxibenzoatos/metabolismo , Família Multigênica , Oxirredução , Filogenia , Resorcinóis/metabolismo
16.
Cien Saude Colet ; 24(1): 219-228, 2019 Jan.
Artigo em Português | MEDLINE | ID: mdl-30698255

RESUMO

The scope of this article was to analyze the evolution of knowledge about Toxocara sp. from a zoonotic point of view by means of scientific data published between the years 1996 and 2015 using epistemology as a tool. The epistemological analysis of the evolution of knowledge on the zoonotic aspect of Toxocara sp. in Brazil revealed that, in general, little new information was added which had, over the period studied, slow and discontinuous absorption, and was not incorporated in the social reality from the standpoint of public health.


Este artigo objetivou analisar a evolução do conhecimento sobre Toxocara sp. em seu aspecto zoonótico por meio de dados científicos entre os anos de 1996 a 2015 utilizando a epistemologia como ferramenta. A análise epistemológica da evolução do conhecimento sobre o aspecto zoonótico de Toxocara sp. no Brasil demonstrou que, de uma maneira geral, foram agregadas poucas novas informações as quais tiveram, ao longo do período estudado, absorção lenta, descontínua, e não foram inseridas na realidade social do ponto de vista de Saúde Pública.


Assuntos
Toxocara/isolamento & purificação , Toxocaríase/epidemiologia , Zoonoses/epidemiologia , Animais , Brasil/epidemiologia , Humanos , Saúde Pública , Toxocaríase/parasitologia , Toxocaríase/transmissão , Zoonoses/parasitologia , Zoonoses/transmissão
17.
Appl Environ Microbiol ; 85(2)2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30389770

RESUMO

The facultative anaerobe Thauera aromatica strain AR-1 uses 3,5-dihydroxybenzoate (3,5-DHB) as a sole carbon and energy source under anoxic conditions using an unusual oxidative strategy to overcome aromatic ring stability. A 25-kb gene cluster organized in four main operons encodes the anaerobic degradation pathway for this aromatic. The dbdR gene coding for a LysR-type transcriptional regulator (LTTR), which is present at the foremost end of the cluster, is required for anaerobic growth on 3,5-DHB and for the expression of the main pathway operons. A model structure of DbdR showed conserved key residues for effector binding with its closest relative TsaR for p-toluenesulfonate degradation. We found that DbdR controlled expression of three promoters upstream from the operons coding for the three main steps of the pathway. While one of them (P orf20 ) was only active in the presence of 3,5-DHB, the other two (P dbhL and P orf18 ) showed moderate basal levels that were further induced in the presence of the pathway substrate, which needed be converted to hydroxyhydroquinone to activate transcription. Both basal and induced activities were strictly dependent on DbdR, which was also required for transcription from its own promoter. DbdR basal expression was moderately high and, unlike most LTTR, increased 2-fold in response to the presence of the effector. DbdR was found to be a tetramer in solution, producing a single retardation complex in binding assays with the three enzymatic promoters, consistent with its tetrameric structure. The three promoters had a conserved organization with a clear putative primary (regulatory) binding site and a putative secondary (activating) binding site positioned at the expected distances from the transcription start site. In contrast, two protein-DNA complexes were observed for the P dbdR promoter, which also showed significant sequence divergence from those of the three other promoters. Taken together, our results show that a single LTTR coordinately controls expression of the entire 3,5-DHB anaerobic degradation pathway in Thauera aromatica AR-1, allowing a fast and optimized response to the presence of the aromatic.IMPORTANCEThauera aromatica AR-1 is a facultative anaerobe that is able to use 3,5-dihydroxybenzoat (3,5-DHB) as the sole carbon and energy source in a process that is dependent on nitrate respiration. We have shown that a single LysR-type regulator with unusual properties, DbdR, controls the expression of the pathway in response to the presence of the substrate; unlike other regulators of the family, DbdR does not repress but activates its own synthesis and is able to bind and activate three promoters directing the synthesis of the pathway enzymes. The promoter architecture is conserved among the three promoters but deviates from that of typical LTTR-dependent promoters. The substrate must be metabolized to an intermediate compound to activate transcription, which requires basal enzyme levels to always be present. The regulatory network present in this strain is designed to allow basal expression of the enzymatic machinery, which would rapidly metabolize the substrate when exposed to it, thus rendering the effector molecule. Once activated, the regulator induces the synthesis of the entire pathway through a positive feedback, increasing expression from all the target promoters to allow maximum growth.


Assuntos
Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Hidroxibenzoatos/metabolismo , Resorcinóis/metabolismo , Thauera/genética , Fatores de Transcrição/genética , Transcrição Gênica , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Alinhamento de Sequência , Thauera/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
19.
Ciênc. Saúde Colet. (Impr.) ; 24(1): 219-228, ene. 2019. tab
Artigo em Português | LILACS | ID: biblio-974804

RESUMO

Resumo Este artigo objetivou analisar a evolução do conhecimento sobre Toxocara sp. em seu aspecto zoonótico por meio de dados científicos entre os anos de 1996 a 2015 utilizando a epistemologia como ferramenta. A análise epistemológica da evolução do conhecimento sobre o aspecto zoonótico de Toxocara sp. no Brasil demonstrou que, de uma maneira geral, foram agregadas poucas novas informações as quais tiveram, ao longo do período estudado, absorção lenta, descontínua, e não foram inseridas na realidade social do ponto de vista de Saúde Pública.


Abstract The scope of this article was to analyze the evolution of knowledge about Toxocara sp. from a zoonotic point of view by means of scientific data published between the years 1996 and 2015 using epistemology as a tool. The epistemological analysis of the evolution of knowledge on the zoonotic aspect of Toxocara sp. in Brazil revealed that, in general, little new information was added which had, over the period studied, slow and discontinuous absorption, and was not incorporated in the social reality from the standpoint of public health.


Assuntos
Humanos , Animais , Toxocara/isolamento & purificação , Toxocaríase/epidemiologia , Zoonoses/epidemiologia , Brasil/epidemiologia , Toxocaríase/parasitologia , Toxocaríase/transmissão , Zoonoses/parasitologia , Zoonoses/transmissão , Saúde Pública
20.
J Physiol Sci ; 68(6): 789-798, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29380149

RESUMO

Maternal behavior has a substantial impact on the behavioral, endocrine, and neural development of the pups. This study investigated the effect of altering the neonatal nutritional environment by modifying the litter size on maternal care and anxiety- and fear-like behaviors in rats during adulthood. On postnatal day (PND) 2, litters were adjusted to a small litter (SL) size of three pups per dam or normal litter (NL) size of 12 pups per dam. Maternal behaviors were scored daily during lactation (PND2-21). The weight gain, food intake, adiposity, and biochemical landmarks of offspring rats were evaluated. On PND60, performances in the open field, elevated plus-maze (EPM), and fear conditioning test were measured. The reduction of the litter size enhanced maternal care in lactating rats, increasing the arched-back posture and licking pups. SL offspring exhibited accelerated weight gain, hyperphagia, increased visceral fat mass, dyslipidemia, and hyperleptinemia in adulthood. The SL offspring of both sexes showed an increase in the anti-thigmotactic effect in the open field, an intact anxious-phenotype in the EPM, and a decrease in the time spent freezing during the fear-conditioning test, compared to NL. The neonatal environment as determined by litter size plays a crucial role in programming the adult metabolic phenotype as well as behavioral responses to stressful stimuli, with an impact on anxiety-like and fear behaviors. These behavioral changes in offspring may be, at least in part, a result of increased maternal care.


Assuntos
Comportamento Animal/fisiologia , Tamanho da Ninhada de Vivíparos , Comportamento Materno/fisiologia , Hipernutrição/metabolismo , Tecido Adiposo/metabolismo , Animais , Animais Recém-Nascidos , Glicemia/análise , Peso Corporal/fisiologia , Ingestão de Alimentos/fisiologia , Feminino , Lipídeos/sangue , Masculino , Ratos
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