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1.
Mol Psychiatry ; 28(4): 1527-1544, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36717740

RESUMO

The RhoGEF TRIO is known to play a major role in neuronal development by controlling actin cytoskeleton remodeling, primarily through the activation of the RAC1 GTPase. Numerous de novo mutations in the TRIO gene have been identified in individuals with neurodevelopmental disorders (NDDs). We have previously established the first phenotype/genotype correlation in TRIO-associated diseases, with striking correlation between the clinical features of the individuals and the opposite modulation of RAC1 activity by TRIO variants targeting different domains. The mutations hyperactivating RAC1 are of particular interest, as they are recurrently found in patients and are associated with a severe form of NDD and macrocephaly, indicating their importance in the etiology of the disease. Yet, it remains unknown how these pathogenic TRIO variants disrupt TRIO activity at a molecular level and how they affect neurodevelopmental processes such as axon outgrowth or guidance. Here we report an additional cohort of individuals carrying a pathogenic TRIO variant that reinforces our initial phenotype/genotype correlation. More importantly, by performing conformation predictions coupled to biochemical validation, we propose a model whereby TRIO is inhibited by an intramolecular fold and NDD-associated variants relieve this inhibition, leading to RAC1 hyperactivation. Moreover, we show that in cultured primary neurons and in the zebrafish developmental model, these gain-of-function variants differentially affect axon outgrowth and branching in vitro and in vivo, as compared to loss-of-function TRIO variants. In summary, by combining clinical, molecular, cellular and in vivo data, we provide compelling new evidence for the pathogenicity of novel genetic variants targeting the TRIO gene in NDDs. We report a novel mechanism whereby the fine-tuned regulation of TRIO activity is critical for proper neuronal development and is disrupted by pathogenic mutations.


Assuntos
Orientação de Axônios , Transtornos do Neurodesenvolvimento , Animais , Transtornos do Neurodesenvolvimento/genética , Neurônios , Fatores de Troca de Nucleotídeo Guanina Rho , Peixe-Zebra , Humanos
2.
Microb Ecol ; 87(1): 88, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943017

RESUMO

Plastic pollution poses a worldwide environmental challenge, affecting wildlife and human health. Assessing the biodegradation capabilities of natural microbiomes in environments contaminated with microplastics is crucial for mitigating the effects of plastic pollution. In this work, we evaluated the potential of landfill leachate (LL) and estuarine sediments (ES) to biodegrade polyethylene (PE), polyethylene terephthalate (PET), and polycaprolactone (PCL), under aerobic, anaerobic, thermophilic, and mesophilic conditions. PCL underwent extensive aerobic biodegradation with LL (99 ± 7%) and ES (78 ± 3%) within 50-60 days. Under anaerobic conditions, LL degraded 87 ± 19% of PCL in 60 days, whereas ES showed minimal biodegradation (3 ± 0.3%). PE and PET showed no notable degradation. Metataxonomics results (16S rRNA sequencing) revealed the presence of highly abundant thermophilic microorganisms assigned to Coprothermobacter sp. (6.8% and 28% relative abundance in anaerobic and aerobic incubations, respectively). Coprothermobacter spp. contain genes encoding two enzymes, an esterase and a thermostable monoacylglycerol lipase, that can potentially catalyze PCL hydrolysis. These results suggest that Coprothermobacter sp. may be pivotal in landfill leachate microbiomes for thermophilic PCL biodegradation across varying conditions. The anaerobic microbial community was dominated by hydrogenotrophic methanogens assigned to Methanothermobacter sp. (21%), pointing at possible syntrophic interactions with Coprothermobacter sp. (a H2-producer) during PCL biodegradation. In the aerobic experiments, fungi dominated the eukaryotic microbial community (e.g., Exophiala (41%), Penicillium (17%), and Mucor (18%)), suggesting that aerobic PCL biodegradation by LL involves collaboration between fungi and bacteria. Our findings bring insights on the microbial communities and microbial interactions mediating plastic biodegradation, offering valuable perspectives for plastic pollution mitigation.


Assuntos
Bactérias , Biodegradação Ambiental , Microbiota , Microplásticos , Instalações de Eliminação de Resíduos , Microplásticos/metabolismo , Bactérias/classificação , Bactérias/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Poluentes Químicos da Água/metabolismo , Poliésteres/metabolismo , Sedimentos Geológicos/microbiologia , RNA Ribossômico 16S/genética , Estuários , Polietileno/metabolismo , Polietilenotereftalatos/metabolismo
3.
Am J Hum Genet ; 106(3): 338-355, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32109419

RESUMO

The Rho-guanine nucleotide exchange factor (RhoGEF) TRIO acts as a key regulator of neuronal migration, axonal outgrowth, axon guidance, and synaptogenesis by activating the GTPase RAC1 and modulating actin cytoskeleton remodeling. Pathogenic variants in TRIO are associated with neurodevelopmental diseases, including intellectual disability (ID) and autism spectrum disorders (ASD). Here, we report the largest international cohort of 24 individuals with confirmed pathogenic missense or nonsense variants in TRIO. The nonsense mutations are spread along the TRIO sequence, and affected individuals show variable neurodevelopmental phenotypes. In contrast, missense variants cluster into two mutational hotspots in the TRIO sequence, one in the seventh spectrin repeat and one in the RAC1-activating GEFD1. Although all individuals in this cohort present with developmental delay and a neuro-behavioral phenotype, individuals with a pathogenic variant in the seventh spectrin repeat have a more severe ID associated with macrocephaly than do most individuals with GEFD1 variants, who display milder ID and microcephaly. Functional studies show that the spectrin and GEFD1 variants cause a TRIO-mediated hyper- or hypo-activation of RAC1, respectively, and we observe a striking correlation between RAC1 activation levels and the head size of the affected individuals. In addition, truncations in TRIO GEFD1 in the vertebrate model X. tropicalis induce defects that are concordant with the human phenotype. This work demonstrates distinct clinical and molecular disorders clustering in the GEFD1 and seventh spectrin repeat domains and highlights the importance of tight control of TRIO-RAC1 signaling in neuronal development.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/genética , Mutação , Transtornos do Neurodesenvolvimento/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas rac1 de Ligação ao GTP/metabolismo , Sequência de Aminoácidos , Estudos de Coortes , Feminino , Fatores de Troca do Nucleotídeo Guanina/química , Células HEK293 , Humanos , Masculino , Fenótipo , Proteínas Serina-Treonina Quinases/química , Homologia de Sequência de Aminoácidos
4.
Traffic ; 14(4): 382-98, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23279168

RESUMO

CREB3 proteins comprise a set of ER-localized bZip transcription factors defined by the presence of a transmembrane domain. They are regulated by inter-compartmental transport, Golgi cleavage and nuclear transport where they promote appropriate transcriptional responses. Although CREB3 proteins play key roles in differentiation, inflammation and metabolism, a general framework relating their defining features to these diverse activities is lacking. We identify unique features of CREB3 organization including the ATB domain, which we show it is essential for transcriptional activity. This domain is absent in all other human bZip factors, but conserved in Drosophila CREBA, which controls secretory pathway genes (SPGs). Furthermore, each of the five human CREB3 factors was capable of activating SPGs in Drosophila, dependent upon the ATB domain. Expression of the CREB3 protein, CREB-H, in 293 cells, upregulated genes involved in secretory capacity, extracellular matrix formation and lipid metabolism and increased secretion of specific cargos. In liver cells, which normally express CREB-H, the active form specifically induced secretion of apolipoproteins, including ApoA-IV, ApoAI, consistent with data implicating CREB-H in metabolic homeostasis. Based on these data and other recent studies, we propose a general role for the CREB3 family in regulating secretory capacity, with particular relevance to specialized cargos.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Regulação da Expressão Gênica , Via Secretória/genética , Apolipoproteínas/metabolismo , Membrana Celular/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/química , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína A de Ligação a Elemento de Resposta do AMP Cíclico/química , Proteína A de Ligação a Elemento de Resposta do AMP Cíclico/genética , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Matriz Extracelular/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Metabolismo dos Lipídeos , Estrutura Terciária de Proteína , Deleção de Sequência , Transcrição Gênica
5.
Life (Basel) ; 14(5)2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38792663

RESUMO

Epilactose is a disaccharide composed of galactose and mannose, and it is currently considered an "under development" prebiotic. In this study, we described the prebiotic potential of epilactose by in vitro fermentation using human fecal inocula from individuals following a Mediterranean diet (DM) or a Vegan diet (DV). The prebiotic effect of epilactose was also compared with lactulose and raffinose, and interesting correlations were established between metabolites and microbiota modulation. The production of several metabolites (lactate, short-chain fatty acids, and gases) confirmed the prebiotic properties of epilactose. For both donors, the microbiota analysis showed that epilactose significantly stimulated the butyrate-producing bacteria, suggesting that its prebiotic effect could be independent of the donor diet. Butyrate is one of the current golden metabolites due to its benefits for the gut and systemic health. In the presence of epilactose, the production of butyrate was 70- and 63-fold higher for the DM donor, when compared to lactulose and raffinose, respectively. For the DV donor, an increase of 29- and 89-fold in the butyrate production was obtained when compared to lactulose and raffinose, respectively. In conclusion, this study suggests that epilactose holds potential functional properties for human health, especially towards the modulation of butyrate-producing strains.

6.
Appl Environ Microbiol ; 79(14): 4239-45, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23645196

RESUMO

Lipids can be anaerobically digested to methane, but methanogens are often considered to be highly sensitive to the long-chain fatty acids (LCFA) deriving from lipids hydrolysis. In this study, the effect of unsaturated (oleate [C18:1]) and saturated (stearate [C18:0] and palmitate [C16:0]) LCFA toward methanogenic archaea was studied in batch enrichments and in pure cultures. Overall, oleate had a more stringent effect on methanogens than saturated LCFA, and the degree of tolerance to LCFA was different among distinct species of methanogens. Methanobacterium formicicum was able to grow in both oleate- and palmitate-degrading enrichments (OM and PM cultures, respectively), whereas Methanospirillum hungatei only survived in a PM culture. The two acetoclastic methanogens tested, Methanosarcina mazei and Methanosaeta concilii, could be detected in both enrichment cultures, with better survival in PM cultures than in OM cultures. Viability tests using live/dead staining further confirmed that exponential growth-phase cultures of M. hungatei are more sensitive to oleate than are M. formicicum cultures; exposure to 0.5 mM oleate damaged 99% ± 1% of the cell membranes of M. hungatei and 53% ± 10% of the cell membranes of M. formicicum. In terms of methanogenic activity, M. hungatei was inhibited for 50% by 0.3, 0.4, and 1 mM oleate, stearate, and palmitate, respectively. M. formicicum was more resilient, since 1 mM oleate and >4 mM stearate or palmitate was needed to cause 50% inhibition on methanogenic activity.


Assuntos
Archaea/fisiologia , DNA Arqueal/genética , Ácido Oleico/metabolismo , Palmitatos/metabolismo , Archaea/classificação , Archaea/genética , Clonagem Molecular , DNA Arqueal/metabolismo , Eletroforese em Gel de Gradiente Desnaturante , Metano/metabolismo , Methanobacterium/genética , Methanobacterium/metabolismo , Methanospirillum/genética , Methanospirillum/metabolismo , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Análise de Sequência de DNA
7.
Traffic ; 11(8): 1092-106, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20477991

RESUMO

Yeast Dop1p is an essential protein that is highly conserved in evolution and whose function is largely unknown. Here, we provide evidence that Dop1p localizes to endosomes and exists in a complex with two other conserved proteins: Neo1p, a P(4)-ATPase and putative flippase, and the scaffolding protein Ysl2p/Mon2p. The latter operates during membrane budding at the tubular endosomal network/trans-Golgi network (TEN/TGN) in a process that includes clathrin recruitment via adaptor proteins. Consistent with a role for Dop1p during this process, temperature-sensitive dop1-3 cells accumulate multivesicular, elongated tubular and ring-like structures similar to those displayed by neo1 and ysl2 mutants. In further agreement with the concept of Dop1p-Neo1p-Ysl2p complex formation and co-operation, we show that dop1-3 cells exhibit reduced levels of Neo1p and Ysl2p at steady state. Conversely, mutations or deletions in NEO1 and YSL2 lead to a decrease in Dop1p levels. In addition to binding to Neo1p and Ysl2p, Dop1p can form dimers or multimers. A critical region for dimerization resides in the C-terminus with leucine zipper-like domains. Dop1p's membrane association is largely mediated by its internal region, but Ysl2p might not be crucial for membrane recruitment.


Assuntos
Adenosina Trifosfatases/metabolismo , Endossomos/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Adenosina Trifosfatases/genética , Membrana Celular/química , Membrana Celular/metabolismo , Endossomos/química , Regulação Fúngica da Expressão Gênica , Proteínas de Membrana Transportadoras/genética , Proteínas Monoméricas de Ligação ao GTP/genética , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Mutação , Proteínas de Transferência de Fosfolipídeos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Transporte Vesicular/genética , Rede trans-Golgi/metabolismo
8.
Environ Res ; 110(1): 112-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19913221

RESUMO

BACKGROUND: Based on a suspicion raised by a health professional and due to a subsequent legal request, a cross-sectional study was made with a comparison group to investigate a possible excess of Hashimoto's thyroiditis-HT and antibodies-ATA in the surroundings of a Petrochemical Complex. METHODS: People of both sexes aged over 20 years were investigated in a random sample of residents in the area surrounding the Petrochemical Complex. Controls were investigated in an area with steel industries. In the areas searched, participants were chosen randomly and stratified a priori by sex and age group. As a result, 90.5% of the expected sample was obtained, totaling 1533 individuals. HT and ATA prevalences were compared by the chi-square test. Logistic regression was used to control the possible confounding factors for HT and ATA. RESULTS: Both TH (9.3%) and ATA (17.6%) prevalences were higher in the Petrochemical Complex area than in the control area (3.9% and 10.3%, respectively). After controlling the possible confounding factors, the POR for living in the surroundings of the Complex and presenting HT was 2.39 (CI95%: 1.42-4.03). According to the ATA criterion, the POR for living in the surroundings of the Complex was 1.78 (CI95%: 1.23-2.60). CONCLUSIONS: The authors have found higher prevalence and risk of developing thyroiditis and anti-thyroid antibodies among residents of areas surrounding the Petrochemical Complex and think these findings need to be further studied in similar areas.


Assuntos
Poluentes Atmosféricos/toxicidade , Indústria Química , Indústrias Extrativas e de Processamento , Doença de Hashimoto/induzido quimicamente , Características de Residência , Adulto , Autoanticorpos/sangue , Autoanticorpos/imunologia , Brasil/epidemiologia , Estudos Transversais , Feminino , Doença de Hashimoto/epidemiologia , Doença de Hashimoto/imunologia , Humanos , Iodo/urina , Masculino , Pessoa de Meia-Idade , Ozônio/toxicidade , Material Particulado/toxicidade , Petróleo , Prevalência , Fatores de Risco , Inquéritos e Questionários , Testes de Função Tireóidea , Adulto Jovem
9.
Mol Biol Cell ; 28(11): 1565-1579, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28381424

RESUMO

CREB-H, an ER-anchored transcription factor, plays a key role in regulating secretion in metabolic pathways, particularly triglyceride homeostasis. It controls the production both of secretory pathway components and cargoes, including apolipoproteins ApoA-IV and ApoC-II, contributing to VLDL/HDL distribution and lipolysis. The key mechanism controlling CREB-H activity involves its ER retention and forward transport to the Golgi, where it is cleaved by Golgi-resident proteases, releasing the N-terminal product, which traffics to the nucleus to effect transcriptional responses. Here we show that a serine-rich motif termed the P-motif, located in the N-terminus between serines 73 and 90, controls release of the precursor transmembrane form from the ER and its forward transport to the Golgi. This motif is subject to GSK-3 phosphorylation, promoting ER retention, while mutation of target serines and drug inhibition of GSK-3 activity coordinately induce both forward transport of the precursor and cleavage, resulting in nuclear import. We previously showed that for the nuclear product, the P-motif is subject to multiple phosphorylations, which regulate stability by targeting the protein to the SCFFbw1a E3 ubiquitin ligase. Thus phosphorylation at the P-motif provides integrated control of CREB-H function, coupling intercompartmental transport in the cytoplasm with stabilization of the active form in the nucleus.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Apolipoproteínas/metabolismo , Apolipoproteínas A , Células COS , Técnicas de Cultura de Células , Núcleo Celular/metabolismo , Chlorocebus aethiops , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Citoplasma/metabolismo , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/fisiologia , Quinase 3 da Glicogênio Sintase/metabolismo , Complexo de Golgi/metabolismo , Complexo de Golgi/fisiologia , Células Hep G2 , Humanos , Lipólise , Fosforilação , Via Secretória , Fatores de Transcrição/metabolismo
10.
J Hum Lact ; 21(4): 439-43, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16280560

RESUMO

This study compared concentrations of total protein, lysozyme, and immunoglobulins (IgA, IgG, IgM) in samples of colostrum (n=101) obtained from mothers of infants<32 weeks, 32 to 36(6) 7 weeks, and >or=37 weeks gestational age, both before and after pasteurization. Total protein was measured by refraction index, lysozyme by the lysoplate method, and immunoglobulins through the radial immunodiffusion technique. The total protein concentration was greater in colostrum of the <32 weeks and 32 to 36(6) 7 weeks categories compared to full-term (P<.001), while concentrations of lysozyme and IgM were similar. IgA concentrations were higher in the <32 weeks group compared to the full-term and similar to the 32 to 36(6) 7 weeks group (P<.05). The IgG was higher in the <32 weeks category compared to 32 to 36(6) 7 weeks, and both were similar to the full-term (P<.05). Pasteurization significantly decreased all of the factors analyzed.


Assuntos
Colostro/imunologia , Manipulação de Alimentos/métodos , Temperatura Alta , Leite Humano/imunologia , Adulto , Análise de Variância , Feminino , Idade Gestacional , Temperatura Alta/efeitos adversos , Humanos , Imunoglobulina A/análise , Imunoglobulina G/análise , Imunoglobulina M/análise , Muramidase/análise
11.
Mol Biol Cell ; 26(16): 2939-54, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26108621

RESUMO

CREB­H, an endoplasmic reticulum-anchored transcription factor, plays a key role in regulating secretion and in metabolic and inflammatory pathways, but how its activity is modulated remains unclear. We examined processing of the nuclear active form and identified a motif around S87-S90 with homology to DSG-type phosphodegrons. We show that this region is subject to multiple phosphorylations, which regulate CREB-H stability by targeting it to the SCF(Fbw1a) E3 ubiquitin ligase. Data from phosphatase treatment, use of phosophospecific antibody, and substitution of serine residues demonstrate phosphorylation of candidate serines in the region, with the core S87/S90 motif representing a critical determinant promoting proteasome-mediated degradation. Candidate kinases CKII and GSK-3b phosphorylate CREB-H in vitro with specificities for different serines. Prior phosphorylation with GSK-3 at one or more of the adjacent serines substantially increases S87/S90-dependent phosphorylation by CKII. In vivo expression of a dominant-negative Cul1 enhances steady-state levels of CREB­H, an effect augmented by Fbw1a. CREB-H directly interacts with Fbw1a in a phosphorylation-dependent manner. Finally, mutations within the phosphodegron, when incorporated into the full-length protein, result in increased levels of constitutively cleaved nuclear protein and increased transcription and secretion of a key endogenous target gene, apolipoprotein A IV.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Ligases SKP Culina F-Box/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Sequência Conservada , Retículo Endoplasmático/metabolismo , Células Hep G2 , Humanos , Camundongos , Fosforilação , Elementos Reguladores de Transcrição , Transdução de Sinais/genética , Ubiquitina/metabolismo
12.
Rev Soc Bras Med Trop ; 36(4): 523-5, 2003.
Artigo em Português | MEDLINE | ID: mdl-12937733

RESUMO

A case is reported of a 19-year-old woman, at week 24 of gestation, with visceral leishmaniosis. She was treated with meglumine antimoniate at a dose of 850 mg/day for 20 days. There occurred premature birth on day five of treatment and the neonate died one day after birth. Considering the importance of protozoiasis in our population and the rarity of the association with pregnancy, we resolved to publish the case.


Assuntos
Aborto Espontâneo/induzido quimicamente , Antimônio/efeitos adversos , Antiprotozoários/efeitos adversos , Leishmaniose Visceral/tratamento farmacológico , Meglumina/efeitos adversos , Complicações Parasitárias na Gravidez/tratamento farmacológico , Adulto , Feminino , Morte Fetal/induzido quimicamente , Humanos , Leishmaniose Visceral/diagnóstico , Gravidez , Complicações Parasitárias na Gravidez/diagnóstico
13.
PLoS One ; 9(11): e111589, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25365506

RESUMO

Previous experiments revealed that DHH1, a RNA helicase involved in the regulation of mRNA stability and translation, complemented the phenotype of a Saccharomyces cerevisiae mutant affected in the expression of genes coding for monocarboxylic-acids transporters, JEN1 and ADY2 (Paiva S, Althoff S, Casal M, Leao C. FEMS Microbiol Lett, 1999, 170:301-306). In wild type cells, JEN1 expression had been shown to be undetectable in the presence of glucose or formic acid, and induced in the presence of lactate. In this work, we show that JEN1 mRNA accumulates in a dhh1 mutant, when formic acid was used as sole carbon source. Dhh1 interacts with the decapping activator Dcp1 and with the deadenylase complex. This led to the hypothesis that JEN1 expression is post-transcriptionally regulated by Dhh1 in formic acid. Analyses of JEN1 mRNAs decay in wild-type and dhh1 mutant strains confirmed this hypothesis. In these conditions, the stabilized JEN1 mRNA was associated to polysomes but no Jen1 protein could be detected, either by measurable lactate carrier activity, Jen1-GFP fluorescence detection or western blots. These results revealed the complexity of the expression regulation of JEN1 in S. cerevisiae and evidenced the importance of DHH1 in this process. Additionally, microarray analyses of dhh1 mutant indicated that Dhh1 plays a large role in metabolic adaptation, suggesting that carbon source changes triggers a complex interplay between transcriptional and post-transcriptional effects.


Assuntos
RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Regulação Fúngica da Expressão Gênica , Transportadores de Ácidos Monocarboxílicos/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Adaptação Fisiológica , Formiatos/metabolismo , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Transportadores de Ácidos Monocarboxílicos/metabolismo , Mutação , Polirribossomos/metabolismo , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Simportadores/genética , Simportadores/metabolismo
14.
Vector Borne Zoonotic Dis ; 9(1): 73-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18847319

RESUMO

The present work evaluated rickettsial infection in dogs and their ticks in an area endemic for Brazilian spotted fever (BSF) in the metropolitan area of São Paulo, Brazil, where the tick Amblyomma aureolatum was presumed to be the vector of the disease. Ticks were collected on dogs from 185 houses, encompassing single infestations by Rhipicephalus sanguineus, Amblyomma aureolatum, Amblyomma longirostre, or Amblyomma sp. in dogs from 60 (32.4%), 77 (41.6%), 2 (1.1%), and 25 (13.5%) houses, respectively; 19 (10.3%) houses had dogs with mixed infestations by R. sanguineus and A. aureolatum; 1 (0.5%) house had dogs with infestations by A. aureolatum and A. longirostre; and 1 (0.5%) house had dogs with infestations by R. sanguineus and Amblyomma sp. Overall, A. aureolatum was present in dogs from 97 (52.4%) houses, and R. sanguineus in dogs from 80 (43.2%) houses. A total of 287 ticks (130 A. aureolatum and 157 R. sanguineus) infesting dogs from 98 houses were selected for testing by polymerase chain reaction (PCR) targeting rickettsial genes. Overall, 3.1% of the A. aureolatum ticks were infected by Rickettsia bellii, and 1.3% of the R. sanguineus were infected by Ricketttsii rickettsii. For serology, we selected 23 dogs living in and in the vicinity of the house where the R. rickettsii-infected ticks were collected. The indirect fluorescent antibody (IFA) test detected antibodies reactive with R. rickettsii in sera from 16 (69.6%) dogs, with titers ranging from 256 to 32,768. It is established that Amblyomma aureolatum is a vector of R. rickettsii in the São Paulo metropolitan area, but our results highlight for the first time in Brazil, a possible role of R. sanguineus in the epidemiology of R. rickettsii, corroborating previous findings in Mexico and the United States, where R. sanguineus has been implicated in the transmission of R. rickettsii to humans.


Assuntos
Vetores Aracnídeos/microbiologia , Doenças do Cão/epidemiologia , Ixodidae/microbiologia , Rickettsia rickettsii/isolamento & purificação , Febre Maculosa das Montanhas Rochosas/veterinária , Animais , Anticorpos Antibacterianos/sangue , Brasil/epidemiologia , DNA Bacteriano/isolamento & purificação , Doenças do Cão/sangue , Doenças do Cão/microbiologia , Doenças do Cão/transmissão , Cães , Feminino , Imunofluorescência , Humanos , Ixodidae/classificação , Masculino , Reação em Cadeia da Polimerase , Rhipicephalus sanguineus/classificação , Rhipicephalus sanguineus/microbiologia , Rickettsia/genética , Rickettsia/imunologia , Rickettsia/isolamento & purificação , Rickettsia rickettsii/genética , Rickettsia rickettsii/imunologia , Febre Maculosa das Montanhas Rochosas/epidemiologia , Febre Maculosa das Montanhas Rochosas/transmissão
15.
Pediatr Diabetes ; 6(4): 206-12, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16390389

RESUMO

OBJECTIVE: Previous reports suggest an increased susceptibility of diabetes patients to infections, but little information is available on possible underlying immunologic dysfunctions. The aim of this study was to evaluate humoral factors in pediatric patients with type 1 diabetes mellitus. METHODS: There were 66 diabetic patients (39 males:27 females; 5-17 yr) classified into two groups according to levels of glycohemoglobin (limit 9%): Group C - controlled (n = 33) and Group UC - uncontrolled (n = 33). We evaluated five patients in C and six in UC who reported previous infections. Immunologic analysis included measurement of plasma concentrations of immunoglobulins (Ig), C3, and C4 levels (turbidimetry); functional hemolytic assays for complement evaluation (CPH for classical and APH for alternative pathways), quantification of C4 isotypes C4A and C4B (ELISA), phagocytosis assays, measurement of bactericidal activity against Staphylococcus aureus, as well as tests of fungicidal capacity for Candida albicans. RESULTS: The UC Group had higher mean age, received higher insulin doses, and had higher concentrations of glycohemoglobin than the C Group. No significant differences in duration of the disease or nutritional conditions were detected between the groups. Lower IgA values in C (10/33) and lower IgG levels in UC (23/33) were detected, and there were inverse relationship with HbA1c values. Analysis of CPH, APH, C3, and C4 showed normal levels in both groups and no statistical correlation with the HbA1c. However, 9/33 children of the UC Group had decreased C3 values. C4B levels were below the normal range in 8/20 and correlated with higher HbA1c. Both phagocytic assays for S. aureus and Candida albicans were within normal limits. CONCLUSIONS: Low IgG concentrations and to some degree reduction in C4B levels were related to impaired metabolic control. No strong link between the immunological alterations was found in diabetic patients and the occurrence of infections.


Assuntos
Formação de Anticorpos/fisiologia , Diabetes Mellitus Tipo 1/imunologia , Suscetibilidade a Doenças/imunologia , Infecções/imunologia , Adolescente , Criança , Pré-Escolar , Complemento C3/metabolismo , Complemento C4/metabolismo , Feminino , Humanos , Imunoglobulinas/sangue , Masculino , Fagocitose
16.
J Infect Dis ; 188(1): 74-80, 2003 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12825174

RESUMO

Brazilian purpuric fever (BPF) is an acute disease caused by Haemophilus influenzae biogroup aegyptius; it is characterized by fever, purpura, and hypotensive shock and is usually fatal. The factors responsible for bacterial virulence and pathogenesis are poorly known. Hemagglutinins have been frequently associated with bacterial virulence, and, in the present study, hemagglutinating activity was detected in extracellular products from H. influenzae biogroup aegyptius strains isolated from patients with BPF. A 60-kilodalton (kDa) molecule absorbable by human O-type erythrocytes was identified by an immunoblot assay; a corresponding fraction was chromatographically purified, and its pathogenic effect was evaluated. Rabbits injected intravenously with either the whole bacterial extracellular product or the 60-kDa fraction showed reactions similar to those seen in patients with BPF: purpura, congestion, and fibrin thrombi in the inner organs. We suggest that this hemagglutinating factor is one of the major pathogenic components of BPF.


Assuntos
Proteínas de Bactérias/metabolismo , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/classificação , Haemophilus influenzae/patogenicidade , Hemaglutininas/metabolismo , Púrpura/microbiologia , Animais , Brasil , Infecções por Haemophilus/patologia , Humanos , Masculino , Coelhos , Virulência
17.
Yeast ; 21(3): 201-10, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14968426

RESUMO

To identify new genes involved in acetate uptake in Saccharomyces cerevisiae, an analysis of the gene expression profiles of cells shifted from glucose to acetic acid was performed. The gene expression reprogramming of yeast adapting to a poor non-fermentable carbon source was observed, including dramatic metabolic changes, global activation of translation machinery, mitochondria biogenesis and the induction of known or putative transporters. Among them, the gene ADY2/YCR010c was identified as a new key element for acetate transport, being homologous to the Yarrowia lipolytica GPR1 gene, which has a role in acetic acid sensitivity. Disruption of ADY2 in S. cerevisiae abolished the active transport of acetate. Microarray analyses of ady2Delta strains showed that this gene is not a critical regulator of acetate response and that its role is directly connected to acetate transport. Ady2p is predicted to be a membrane protein and is a valuable acetate transporter candidate.


Assuntos
Ácido Acético/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transporte Biológico/fisiologia , DNA Fúngico/química , DNA Fúngico/genética , Regulação Fúngica da Expressão Gênica , Transportadores de Ácidos Monocarboxílicos/metabolismo , Mutagênese Insercional , Análise de Sequência com Séries de Oligonucleotídeos , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/biossíntese , Proteínas de Saccharomyces cerevisiae/genética
18.
Endocr Pathol ; 8(1): 37-47, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-12114670

RESUMO

Two unrelated families (CA and NA) in which an iodide organification defect (lOD) was present in two siblings of each family were studied. These patients had congenital goiters with hypothyroidism and a positive perchlorate discharge test. Examination of the thyroid tissue revealed no thyroid peroxidase (TPO) activity. Histologic findings were consistent with a microfollicular pattern of hyperplasia. Moderate cellular atypia was present, characterized by nuclear pleomorphism and hyperchromatism. Full length thyroglobulin was purified by gel filtration, but was not iodinated. Immunohistochemical studies using a polyclonal anti-human thyroid peroxidase (hTPO) antibody confirmed the presence of immunoreactive TPO protein in the thyroid tissues. Samples of normal and affected individuals were studied with respect to the presence of various fragments using TPO probes of varying sizes. The two affected siblings from family CA were homozygous for fragments 3.9, 4.6, and 7.0 kb (8g111) and 2.3 and 2.9 kb (Ta ql), whereas the parents were heterozygous. In the other family (NA), the Bg/ll digestion and TPO-31 hybridization revealed an interesting and informative polymorphism. The parents showed two different polymorphic patterns: the father had a 5.0/4.6 kb pattern and the mother a 4.7/4.5 kb pattern. However, the two affected siblings showed the same heterozygotic allelic pattern at 4.5/4.6 kb. The restriction fragment length polymorphism detected in these two families suggests an association between the TPO gene and an lOD. Results suggest that in these dyshormonogenetic tissues an altered TPO protein molecule is being synthesized, without detectable in vitro activity, but visible by immunostaining techniques in the goitrous tissue. Mutations in the TPC gene sequence are most likely associated with these changes.

19.
Physis (Rio J.) ; 16(2): 317-350, 2006.
Artigo em Português | LILACS | ID: lil-447571

RESUMO

O presente artigo apresenta uma reflexão a partir de alguns dos resultados obtidos no projeto de pesquisa Qualidade de vida em sociedades complexas: a depressão entre trabalhadores da indústria petroquímica e pescadores artesanais. Vale ressaltar que a pesquisa é parte considerável de um caminho mais longo desenvolvido desde os anos 90. Através de intensa pesquisa de campo, analisou-se a qualidade de vida, através da observação dos estados depressivos presentes nos trabalhadores da indústria petroquímica (REPLAN, Paulínia, SP) e pescadores artesanais (Colônia Z 7 - Itaipu e Piratininga, Niterói, RJ), considerando que esses trabalhadores estão submetidos a intensas transformações socioambientais ocorridas em seus cotidianos e manifestam a depressão como expressão da subjetivação, no indivíduo, de uma intensa complexidade social.


This paper presents a reflection based on some results of the research project Quality of life in complex societies: the depression between workers of petrochemical industry and artisan fishermen. Is must be pointed out that this research is a large part of a deep theory developed since the 90's. In a deep field research, the quality of life through analysis of depressive states in workers of the petrochemical industry (REPLAN, Paulínia, SP) and artisan fishermen (7 Colony Z - Itaipu and Piratininga, Niterói, Rio de Janeiro) was examined, considering that these workers are under intense social-environmental transformations in their daily routine and revealing depression as expression of subjectivity, in the individual, of an intense social complexity.


Assuntos
Depressão , Qualidade de Vida , Condições Sociais , Categorias de Trabalhadores
20.
Acta ortop. bras ; Acta ortop. bras;13(2)2005. ilus, tab
Artigo em Português, Inglês | LILACS | ID: lil-404151

RESUMO

Os autores apresentaram um estudo prospectivo de quatro pacientes portadores de pseudo-artrose no terço distal do rádio. Dois eram do sexo feminino e dois do masculino, com idade média de 42,5 anos. O diagnóstico de pseudo-artrose foi realizado em média com 5,3 meses após o trauma. Um paciente apresentava, como antecedente mórbido pessoal, epilepsia e osteoporose, outros dois relataram tabagismo e obesidade e o quarto, fratura exposta. O tratamento consistiu de osteossíntese interna e enxertia com osso autógeno. Todos foram submetidos à avaliação clínica pré e pós-operatória quanto à força de preensão palmar e arco de movimentos do punho. Houve 100 por cento de consolidação das fraturas do terço distal do rádio em pseudo-artrose e retorno dos pacientes às atividades profissionais.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Fraturas não Consolidadas , Pseudoartrose , Rádio (Anatomia) , Pseudoartrose
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