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1.
Cell ; 175(2): 514-529.e20, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30220461

RESUMO

The mechanisms underlying sterol transport in mammalian cells are poorly understood. In particular, how cholesterol internalized from HDL is made available to the cell for storage or modification is unknown. Here, we describe three ER-resident proteins (Aster-A, -B, -C) that bind cholesterol and facilitate its removal from the plasma membrane. The crystal structure of the central domain of Aster-A broadly resembles the sterol-binding fold of mammalian StARD proteins, but sequence differences in the Aster pocket result in a distinct mode of ligand binding. The Aster N-terminal GRAM domain binds phosphatidylserine and mediates Aster recruitment to plasma membrane-ER contact sites in response to cholesterol accumulation in the plasma membrane. Mice lacking Aster-B are deficient in adrenal cholesterol ester storage and steroidogenesis because of an inability to transport cholesterol from SR-BI to the ER. These findings identify a nonvesicular pathway for plasma membrane to ER sterol trafficking in mammals.


Assuntos
HDL-Colesterol/metabolismo , Proteínas de Membrana/fisiologia , Proteínas de Membrana/ultraestrutura , Células 3T3 , Animais , Transporte Biológico/fisiologia , Antígenos CD36/metabolismo , Células CHO , Proteínas de Transporte/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Membrana Celular/fisiologia , Colesterol/metabolismo , Cricetulus , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/fisiologia , Humanos , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Membranas Mitocondriais/metabolismo , Alinhamento de Sequência , Esteróis/metabolismo
2.
Nature ; 629(8014): 1174-1181, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38720073

RESUMO

Phosphorylation of proteins on tyrosine (Tyr) residues evolved in metazoan organisms as a mechanism of coordinating tissue growth1. Multicellular eukaryotes typically have more than 50 distinct protein Tyr kinases that catalyse the phosphorylation of thousands of Tyr residues throughout the proteome1-3. How a given Tyr kinase can phosphorylate a specific subset of proteins at unique Tyr sites is only partially understood4-7. Here we used combinatorial peptide arrays to profile the substrate sequence specificity of all human Tyr kinases. Globally, the Tyr kinases demonstrate considerable diversity in optimal patterns of residues surrounding the site of phosphorylation, revealing the functional organization of the human Tyr kinome by substrate motif preference. Using this information, Tyr kinases that are most compatible with phosphorylating any Tyr site can be identified. Analysis of mass spectrometry phosphoproteomic datasets using this compendium of kinase specificities accurately identifies specific Tyr kinases that are dysregulated in cells after stimulation with growth factors, treatment with anti-cancer drugs or expression of oncogenic variants. Furthermore, the topology of known Tyr signalling networks naturally emerged from a comparison of the sequence specificities of the Tyr kinases and the SH2 phosphotyrosine (pTyr)-binding domains. Finally we show that the intrinsic substrate specificity of Tyr kinases has remained fundamentally unchanged from worms to humans, suggesting that the fidelity between Tyr kinases and their protein substrate sequences has been maintained across hundreds of millions of years of evolution.


Assuntos
Fosfotirosina , Proteínas Tirosina Quinases , Especificidade por Substrato , Tirosina , Animais , Humanos , Motivos de Aminoácidos , Evolução Molecular , Espectrometria de Massas , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Fosforilação , Fosfotirosina/metabolismo , Proteínas Tirosina Quinases/efeitos dos fármacos , Proteínas Tirosina Quinases/metabolismo , Proteoma/química , Proteoma/metabolismo , Proteômica , Transdução de Sinais , Domínios de Homologia de src , Tirosina/metabolismo , Tirosina/química
3.
Proc Natl Acad Sci U S A ; 118(4)2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33483422

RESUMO

In mammalian cells, nutrients and growth factors signal through an array of upstream proteins to regulate the mTORC1 growth control pathway. Because the full complement of these proteins has not been systematically identified, we developed a FACS-based CRISPR-Cas9 genetic screening strategy to pinpoint genes that regulate mTORC1 activity. Along with almost all known positive components of the mTORC1 pathway, we identified many genes that impact mTORC1 activity, including DCAF7, CSNK2B, SRSF2, IRS4, CCDC43, and HSD17B10 Using the genome-wide screening data, we generated a focused sublibrary containing single guide RNAs (sgRNAs) targeting hundreds of genes and carried out epistasis screens in cells lacking nutrient- and stress-responsive mTORC1 modulators, including GATOR1, AMPK, GCN2, and ATF4. From these data, we pinpointed mitochondrial function as a particularly important input into mTORC1 signaling. While it is well appreciated that mitochondria signal to mTORC1, the mechanisms are not completely clear. We find that the kinases AMPK and HRI signal, with varying kinetics, mitochondrial distress to mTORC1, and that HRI acts through the ATF4-dependent up-regulation of both Sestrin2 and Redd1. Loss of both AMPK and HRI is sufficient to render mTORC1 signaling largely resistant to mitochondrial dysfunction induced by the ATP synthase inhibitor oligomycin as well as the electron transport chain inhibitors piericidin and antimycin. Taken together, our data reveal a catalog of genes that impact the mTORC1 pathway and clarify the multifaceted ways in which mTORC1 senses mitochondrial dysfunction.


Assuntos
Fator 4 Ativador da Transcrição/genética , Edição de Genes/métodos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Mitocôndrias/genética , Proteínas Serina-Treonina Quinases/genética , 3-Hidroxiacil-CoA Desidrogenases/genética , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Aminoácidos/deficiência , Aminoácidos/farmacologia , Antimicina A/análogos & derivados , Antimicina A/farmacologia , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas , Meios de Cultura/química , Meios de Cultura/farmacologia , Regulação da Expressão Gênica , Genoma Humano , Glucose/deficiência , Glucose/farmacologia , Células HEK293 , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Oligomicinas/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , RNA Guia de Cinetoplastídeos/genética , RNA Guia de Cinetoplastídeos/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Transdução de Sinais , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
4.
Nature ; 543(7645): 438-442, 2017 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-28199306

RESUMO

The mechanistic target of rapamycin complex 1 (mTORC1) is a central regulator of cell growth that responds to diverse environmental signals and is deregulated in many human diseases, including cancer and epilepsy. Amino acids are a key input to this system, and act through the Rag GTPases to promote the translocation of mTORC1 to the lysosomal surface, its site of activation. Multiple protein complexes regulate the Rag GTPases in response to amino acids, including GATOR1, a GTPase activating protein for RAGA, and GATOR2, a positive regulator of unknown molecular function. Here we identify a protein complex (KICSTOR) that is composed of four proteins, KPTN, ITFG2, C12orf66 and SZT2, and that is required for amino acid or glucose deprivation to inhibit mTORC1 in cultured human cells. In mice that lack SZT2, mTORC1 signalling is increased in several tissues, including in neurons in the brain. KICSTOR localizes to lysosomes; binds and recruits GATOR1, but not GATOR2, to the lysosomal surface; and is necessary for the interaction of GATOR1 with its substrates, the Rag GTPases, and with GATOR2. Notably, several KICSTOR components are mutated in neurological diseases associated with mutations that lead to hyperactive mTORC1 signalling. Thus, KICSTOR is a lysosome-associated negative regulator of mTORC1 signalling, which, like GATOR1, is mutated in human disease.


Assuntos
Proteínas de Transporte/metabolismo , Lisossomos/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Aminoácidos/metabolismo , Animais , Proteínas de Transporte/química , Proteínas de Transporte/genética , Linhagem Celular , Feminino , Proteínas Ativadoras de GTPase , Glucose/deficiência , Glucose/metabolismo , Humanos , Cadeias alfa de Integrinas , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Proteínas dos Microfilamentos/química , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Complexos Multiproteicos/antagonistas & inibidores , Complexos Multiproteicos/química , Complexos Multiproteicos/genética , Mutação , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Ligação Proteica , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais , Especificidade por Substrato , Serina-Treonina Quinases TOR/antagonistas & inibidores
5.
Biol Sport ; 40(3): 805-811, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37398963

RESUMO

The purpose of this study was to investigate the validity of a low-cost friction encoder against a criterion measure (strain gauge combined with a linear encoder) for assessing velocity, force and power in flywheel exercise devices. Ten young and physically active volunteers performed two sets of 14 maximal squats on a flywheel inertial device (YoYo Technology, Stockholm, Sweden) with five minutes rest between each set. Two different resistances were used (0.075 kg · m2 for the first set; 0.025 kg · m2 for the second). Mean velocity (Vrep), force (Frep) and power (Prep) for each repetition were assessed simultaneously via a friction encoder (Chronojump, Barcelona, Spain), and with a strain gauge combined with a linear encoder (MuscleLab 6000, Ergotest Technology, Porsgrunn, Norway). Results are displayed as (Mean [CI 90%]). Compared to criterion measures, mean bias for the practical measures of Vrep, Frep and Prep were moderate (-0.95 [-0.99 to -0.92]), small (0.53 [0.50 to 0.56]) and moderate (-0.68 [-0.71 to -0.65]) respectively. The typical error of estimate (TEE) was small for all three parameters; Vrep (0.23 [0.20 to 0.25]), Frep (0.20 [0.18 to 0.22]) and Prep (0.18 [0.16 to 0.20]). Correlations with MuscleLab were nearly perfect for all measures in all load configurations. Based on these findings, the friction encoder provides valid measures of velocity, force and power in flywheel exercise devices. However, as error did exist between measures, the same testing protocol should be used when assessing changes in these parameters over time, or when aiming to perform inter-individual comparisons.

6.
Biol Sport ; 40(1): 161-170, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36636175

RESUMO

The aim of this study was to identify between-position (forwards vs. backs) differences in movement variability in cumulative tackle events training during both attacking and defensive roles. Eleven elite adolescent male rugby league players volunteered to participate in this study (mean ± SD, age; 18.5 ± 0.5 years, height; 179.5 ± 5.0 cm, body mass; 88.3 ± 13.0 kg). Participants performed a drill encompassing four blocks of six tackling (i.e. tackling an opponent) and six tackled (i.e. being tackled by an opponent while carrying a ball) events (i.e. 48 total tackles) while wearing a micro-technological inertial measurement unit (WIMU, Realtrack Systems, Spain). The acceleration data were used to calculate sample entropy (SampEn) to analyse the movement variability during tackles performance. In tackling actions SampEn showed significant between-position differences in block 1 (p = 0.0001) and block 2 (p = 0.0003). Significant between-block differences were observed in backs (block 1 vs 3, p = 0,0021; and block 1 vs 4, p = 0,0001) but not in forwards. When being tackled, SampEn showed significant between-position differences in block 1 (p = 0.0007) and block 3 (p = 0.0118). Significant between-block differences were only observed for backs in block 1 vs 4 (p = 0,0025). Movement variability shows a progressive reduction with cumulative tackle events, especially in backs and when in the defensive role (tackling). Forwards present lower movement variability values in all blocks, particularly in the first block, both in the attacking and defensive role. Entropy measures can be used by practitioners as an alternative tool to analyse the temporal structure of variability of tackle actions and quantify the load of these actions according to playing position.

7.
J Virol ; 94(18)2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32641486

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has affected most countries in the world. Studying the evolution and transmission patterns in different countries is crucial to enabling implementation of effective strategies for disease control and prevention. In this work, we present the full genome sequence for 17 SARS-CoV-2 isolates corresponding to the earliest sampled cases in Mexico. Global and local phylogenomics, coupled with mutational analysis, consistently revealed that these viral sequences are distributed within 2 known lineages, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lineage A/G, containing mostly sequences from North America, and lineage B/S, containing mainly sequences from Europe. Based on the exposure history of the cases and on the phylogenomic analysis, we characterized 14 independent introduction events. Additionally, three cases with no travel history were identified. We found evidence that two of these cases represented local transmission cases occurring in Mexico during mid-March 2020, denoting the earliest events described for the country. Within this local transmission cluster, we also identified an H49Y amino acid change in the Spike protein. This mutation represents a homoplasy occurring independently through time and space and may function as a molecular marker to follow any further spread of these viral variants throughout the country. Our results provide a general picture of the SARS-CoV-2 variants introduced at the beginning of the outbreak in Mexico, setting the foundation for future surveillance efforts.IMPORTANCE Understanding the introduction, spread, and establishment of SARS-CoV-2 within distinct human populations as well as the evolution of the pandemics is crucial to implement effective control strategies. In this work, we report that the initial virus strains introduced in Mexico came from Europe and the United States and that the virus was circulating locally in the country as early as mid-March. We also found evidence for early local transmission of strains with a H49Y mutation in the Spike protein, which could be further used as a molecular marker to follow viral spread within the country and the region.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Variação Genética , Genoma Viral , Genômica , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Substituição de Aminoácidos , Betacoronavirus/classificação , COVID-19 , Biologia Computacional/métodos , Infecções por Coronavirus/transmissão , Genômica/métodos , Humanos , México/epidemiologia , Mutação , Pandemias , Filogenia , Pneumonia Viral/transmissão , SARS-CoV-2
8.
Arch Virol ; 166(11): 3173-3177, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34448936

RESUMO

SARS-CoV-2 variants emerged in late 2020, and at least three variants of concern (B.1.1.7, B.1.351, and P1) have been reported by WHO. These variants have several substitutions in the spike protein that affect receptor binding; they exhibit increased transmissibility and may be associated with reduced vaccine effectiveness. In the present work, we report the identification of a potential variant of interest, harboring the mutations T478K, P681H, and T732A in the spike protein, within the newly named lineage B.1.1.519, that rapidly outcompeted the preexisting variants in Mexico and has been the dominant virus in the country during the first trimester of 2021.


Assuntos
COVID-19/epidemiologia , COVID-19/virologia , SARS-CoV-2/genética , COVID-19/transmissão , Genoma Viral/genética , Humanos , México/epidemiologia , Mutação , Filogenia , Prevalência , SARS-CoV-2/classificação , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/genética
9.
J Nematol ; 532021.
Artigo em Inglês | MEDLINE | ID: mdl-34671749

RESUMO

Organic and conventional production are common in horticulture crops and each system may exert a different influence on the soil ecosystem, particularly the nematode community. Crop nutrient rate is an important choice in both production systems. The objectives of this study were to assess the impacts of (i) organic and conventional production systems and (ii) nutrient rate in both systems on the nematode community in carrot production. To investigate these objectives, field studies in organic and conventional production - which included fumigation with 1,3-dichloropropene - were conducted in North-Central Florida. In both production systems, nutrient rate treatments were 168, 224, 280, 336, and 392 kg N/ha. Poultry litter was the nitrogen source in organic production whereas synthetic, inorganic fertilizer was used in conventional production. All nematode trophic groups were consistently more abundant in organic than conventional production. The nematode community was more diverse and had greater trophic structure in organic production. Greater rates of organic nutrients increased enrichment opportunists (bacterivores and fungivores), but inconsistently across years. Conventional production had similar results except that only moderate nutrient rates increased fungivore abundances. Extreme enrichment opportunists (Rhabditis spp.) drove bacterivore trends in organic production whereas moderate enrichment opportunists (Cephalobus spp.) drove trends in conventional production. Nutrient rates did not affect omnivore-predators, herbivores, nematode community diversity, or structure in either system. In summary, type of production system, organic or conventional, exerts a strong influence on the nematode community, but nutrient rate has less consistent effects in horticulture production.

10.
J Neurochem ; 155(5): 559-576, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32379343

RESUMO

Lipotoxicity (LTx) leads to cellular dysfunction and cell death and has been proposed to be an underlying process during traumatic and hypoxic injuries and neurodegenerative conditions in the nervous system. This study examines cellular mechanisms responsible for docosahexaenoic acid (DHA 22:6 n-3) protection in nerve growth factor-differentiated pheochromocytoma (NGFDPC12) cells from palmitic acid (PAM)-mediated lipotoxicity (PAM-LTx). NGFDPC12 cells exposed to PAM show a significant lipotoxicity demonstrated by a robust loss of cell viability, apoptosis, and increased HIF-1α and BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 gene expression. Treatment of NGFDPC12 cells undergoing PAM-LTx with the pan-caspase inhibitor ZVAD did not protect, but shifted the process from apoptosis to necroptosis. This shift in cell death mechanism was evident by the appearance of the signature necroptotic Topo I protein cleavage fragments, phosphorylation of mixed lineage kinase domain-like, and inhibition with necrostatin-1. Cultures exposed to PAM and co-treated with necrostatin-1 (necroptosis inhibitor) and rapamycin (autophagy promoter), showed a significant protection against PAM-LTx compared to necrostatin-1 alone. In addition, co-treatment with DHA, as well as 20:5 n-3, 20:4 n-6, and 22:5 n-3, in the presence of PAM protected NGFDPC12 cells against LTx. DHA-induced neuroprotection includes restoring normal levels of HIF-1α and BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 transcripts and caspase 8 and caspase 3 activity, phosphorylation of beclin-1, de-phosphorylation of mixed lineage kinase domain-like, increase in LC3-II, and up-regulation of Atg7 and Atg12 genes, suggesting activation of autophagy and inhibition of necroptosis. Furthermore, DHA-induced protection was suppressed by the lysosomotropic agent chloroquine, an inhibitor of autophagy. We conclude that DHA elicits neuroprotection by regulating multiple cell death pathways including enhancement of autophagy and inhibiting apoptosis and necroptosis.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Fator de Crescimento Neural/farmacologia , Ácido Palmítico/toxicidade , Animais , Apoptose/fisiologia , Autofagia/fisiologia , Diferenciação Celular/fisiologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/fisiologia , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismo
11.
Arch Virol ; 165(9): 2095-2098, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32556599

RESUMO

SARS-CoV-2 was first detected in the city of Wuhan, Hubei Province, China. In this report, we describe the complete genome sequence of the first imported SARS-CoV-2, detected in a Mexican patient who had traveled to Bergamo, Italy. Phylogenetic analysis showed that this isolate belongs to subclade A2a (lineage G) and is closely related to isolates from Finland, Germany and Brazil, all of which were from patients with a history of travel to Italy. This is the first report of the complete genome sequence of this virus in Mexico.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/virologia , Genoma Viral , Pneumonia Viral/virologia , Adulto , Sequência de Bases , Betacoronavirus/classificação , Betacoronavirus/isolamento & purificação , COVID-19 , Humanos , Masculino , México , Pandemias , Filogenia , SARS-CoV-2 , Sequenciamento Completo do Genoma
12.
J Biol Chem ; 291(20): 10635-45, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-27022023

RESUMO

Methionine is an essential sulfur amino acid that is engaged in key cellular functions such as protein synthesis and is a precursor for critical metabolites involved in maintaining cellular homeostasis. In mammals, in response to nutrient conditions, the liver plays a significant role in regulating methionine concentrations by altering its flux through the transmethylation, transsulfuration, and transamination metabolic pathways. A comprehensive understanding of how hepatic methionine metabolism intersects with other regulatory nutrient signaling and transcriptional events is, however, lacking. Here, we show that methionine and derived-sulfur metabolites in the transamination pathway activate the GCN5 acetyltransferase promoting acetylation of the transcriptional coactivator PGC-1α to control hepatic gluconeogenesis. Methionine was the only essential amino acid that rapidly induced PGC-1α acetylation through activating the GCN5 acetyltransferase. Experiments employing metabolic pathway intermediates revealed that methionine transamination, and not the transmethylation or transsulfuration pathways, contributed to methionine-induced PGC-1α acetylation. Moreover, aminooxyacetic acid, a transaminase inhibitor, was able to potently suppress PGC-1α acetylation stimulated by methionine, which was accompanied by predicted alterations in PGC-1α-mediated gluconeogenic gene expression and glucose production in primary murine hepatocytes. Methionine administration in mice likewise induced hepatic PGC-1α acetylation, suppressed the gluconeogenic gene program, and lowered glycemia, indicating that a similar phenomenon occurs in vivo These results highlight a communication between methionine metabolism and PGC-1α-mediated hepatic gluconeogenesis, suggesting that influencing methionine metabolic flux has the potential to be therapeutically exploited for diabetes treatment.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Gluconeogênese/efeitos dos fármacos , Histona Acetiltransferases/biossíntese , Fígado/metabolismo , Metionina/farmacologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição de p300-CBP/biossíntese , Acetilação/efeitos dos fármacos , Animais , Gluconeogênese/genética , Células Hep G2 , Histona Acetiltransferases/genética , Humanos , Camundongos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Fatores de Transcrição/genética , Fatores de Transcrição de p300-CBP/genética
14.
Respiration ; 93(6): 424-429, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28355600

RESUMO

BACKGROUND: There are few published studies about the usefulness of endobronchial ultrasound (EBUS) in patients infected with human immunodeficiency virus (HIV). The clinical spectrum of likely diseases in this population is varied and differs from patients not infected with HIV. OBJECTIVE: The aim of this study was to measure the usefulness of EBUS-guided transbronchial needle aspiration (EBUS-TBNA) in HIV-infected patients with mediastinal lymphadenopathy. MATERIALS AND METHODS: We conducted an observational, cross-sectional, retrospective, descriptive study on patients with HIV infection and mediastinal lymphadenopathy who underwent EBUS-TBNA between September 2014 and April 2016. The patients' final diagnosis, regardless of the sample from which it was obtained, was considered the positive gold standard, and the absence of diagnosis was the negative. The study measured diagnostic accuracy of bronchoalveolar lavage (BAL), transbronchial biopsy (TBB), and EBUS-TBNA. RESULTS: A total of 43 procedures were performed; 79.1% (34/43) of the patients were male, and the median age was 35 years (range, 22-66). The overall diagnostic yield including all types of samples was 90.7% (39/43); the yield of BAL was 50% (21), that of TBB 61.9% (26), and that of EBUS-TBNA was 60.5% (26). The combined yield of BAL with TBB was 69.8% (30); the yield of BAL with EBUS-TBNA was 86% (37) and that of TBB with EBUS-TBNA was 88.4% (38). The highest diagnostic accuracy was 97.7% for the combination of TBB and EBUS-TBNA. CONCLUSIONS: The most common infectious diagnoses were tuberculosis, with a higher diagnostic accuracy using EBUS-TBNA than BAL. With malignancies, both EBUS-TBNA and TBB were useful. EBUS-TBNA is a minimally invasive diagnostic tool that should be considered in these patients.


Assuntos
Adenocarcinoma/diagnóstico , Infecções por HIV/complicações , Infecções/diagnóstico , Neoplasias Pulmonares/diagnóstico , Linfadenopatia/diagnóstico , Linfoma Difuso de Grandes Células B/diagnóstico , Doenças do Mediastino/diagnóstico , Sarcoma de Kaposi/diagnóstico , Adenocarcinoma/complicações , Adenocarcinoma/patologia , Adulto , Idoso , Infecções Bacterianas/complicações , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/patologia , Lavagem Broncoalveolar , Broncoscopia , Estudos Transversais , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Endossonografia , Feminino , Humanos , Infecções/complicações , Infecções/patologia , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/patologia , Linfadenopatia/complicações , Linfadenopatia/patologia , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/patologia , Masculino , Doenças do Mediastino/complicações , Doenças do Mediastino/patologia , Mediastino , Pessoa de Meia-Idade , Micoses/complicações , Micoses/diagnóstico , Micoses/patologia , Estudos Retrospectivos , Sarcoma de Kaposi/complicações , Sarcoma de Kaposi/patologia , Sensibilidade e Especificidade , Tuberculose dos Linfonodos/complicações , Tuberculose dos Linfonodos/diagnóstico , Tuberculose dos Linfonodos/patologia , Viroses/complicações , Viroses/diagnóstico , Viroses/patologia , Adulto Jovem
15.
Respiration ; 94(3): 285-292, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28743122

RESUMO

BACKGROUND: Transbronchial lung cryobiopsy (TLCB), performed with a flexible cryoprobe, is an interventional pulmonology procedure that has proved its diagnostic value for interstitial pulmonary disease. However, it has not been explored extensively as a diagnostic tool for patients with non-interstitial lung pathology, including infectious and malignant diseases. OBJECTIVE: To evaluate the diagnostic yield and safety of an interventional pulmonology approach that integrates TLCB and bronchoalveolar lavage (BAL) for the diagnosis of non-interstitial pulmonary disease. METHODS: TLCB and BAL were performed under general anesthesia through the same bronchoscopic access on 103 adult patients (including immunocompromised HIV+ individuals) with clinical/radiological evidence of non-interstitial lung disease admitted to the Interventional Pulmonology Service between May 2015 and April 2016. Samples obtained were sent to pathology and microbiology laboratories for standard diagnostic analysis. RESULTS: Samples of TLCB allowed the diagnosis of 75.7% of patients, while 39.8% were diagnosed from BAL. The global diagnostic yield from the dual sampling was 92.2%. TLCB allowed the diagnosis of 94.7% of cancer cases and 60.0% of infectious cases, while BAL samples identified 77.5% of infectious cases and 21.2% of malignant lesions. The incidence of complications was 4.9% with full recovery in all cases. CONCLUSIONS: Simultaneous TLCB and BAL constitute a safe and useful diagnostic procedure for non-interstitial pulmonary disease, with a global diagnostic yield of 92.2%. Complementary advantages of samples obtained by each technique result in a robust diagnostic strategy for infectious and malignant disease in adults, including HIV+ individuals.


Assuntos
Broncoscopia/estatística & dados numéricos , Pneumopatias/diagnóstico , Pulmão/patologia , Adulto , Idoso , Biópsia , Broncoscopia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
16.
Am J Physiol Heart Circ Physiol ; 311(2): H384-94, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27342876

RESUMO

Lymphatic vessels modulate tissue fluid balance and inflammation and provide a conduit for endocrine and lipid transport. The growth of new lymphatic vessels in the adult, lymphangiogenesis, is predominantly mediated through vascular endothelial growth factor receptor-3 (VEGFR-3) signaling. We took advantage of the unique binding of murine VEGF-D specifically to VEGFR-3 and generated mice capable of inducible, tissue-specific expression of murine VEGF-D under a tightly-controlled tetracycline response element (TRE) promoter to stimulate adult tissue lymphangiogenesis. With doxycycline-activated expression, TRE-VEGF-D mouse crossed to mice with tissue-specific promoters for the lung [Clara cell secretory protein-reverse tetracycline transactivator (rtTA)] developed pulmonary lymphangiectasia. In the kidney, (kidney-specific protein-rtTA × TRE-VEGF-D) mice exhibited rapid lymphatic hyperplasia on induction of VEGF-D expression. Crossed with adipocyte-specific adiponectin-rtTA mice [Adipo-VEGF-D (VD)], chronic VEGF-D overexpression was capable of inducing de novo lymphangiogenesis in white adipose tissue and a massive expansion of brown adipose tissue lymphatics. VEGF-D expression in white adipose tissue also increased macrophage infiltration and tissue fibrosis in the tissue. Expression did not, however, measurably affect peripheral fluid transport, the blood vasculature, or basal metabolic parameters. On removal of the doxycycline stimulus, VEGF-D expression returned to normal, and the expanded adipose tissue lymphatics regressed in Adipo-VD mice. The inducible TRE-VEGF-D mouse thus provides a novel murine platform to study the adult mechanisms and therapies of an array of disease- and tissue-specific models of lymphangiogenesis.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Rim/metabolismo , Pulmão/metabolismo , Linfonodos/metabolismo , Linfangiogênese/genética , Vasos Linfáticos/patologia , Fator D de Crescimento do Endotélio Vascular/genética , Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/patologia , Animais , Composição Corporal , Feminino , Imunofluorescência , Hiperplasia , Rim/patologia , Pulmão/patologia , Linfonodos/patologia , Masculino , Camundongos , Camundongos Transgênicos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor 3 de Fatores de Crescimento do Endotélio Vascular
17.
PLoS Genet ; 9(5): e1003510, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23671426

RESUMO

The Caenorhabditis elegans spermatheca is a myoepithelial tube that stores sperm and undergoes cycles of stretching and constriction as oocytes enter, are fertilized, and exit into the uterus. FLN-1/filamin, a stretch-sensitive structural and signaling scaffold, and PLC-1/phospholipase C-ε, an enzyme that generates the second messenger IP3, are required for embryos to exit normally after fertilization. Using GCaMP, a genetically encoded calcium indicator, we show that entry of an oocyte into the spermatheca initiates a distinctive series of IP3-dependent calcium oscillations that propagate across the tissue via gap junctions and lead to constriction of the spermatheca. PLC-1 is required for the calcium release mechanism triggered by oocyte entry, and FLN-1 is required for timely initiation of the calcium oscillations. INX-12, a gap junction subunit, coordinates propagation of the calcium transients across the spermatheca. Gain-of-function mutations in ITR-1/IP3R, an IP3-dependent calcium channel, and loss-of-function mutations in LFE-2, a negative regulator of IP3 signaling, increase calcium release and suppress the exit defect in filamin-deficient animals. We further demonstrate that a regulatory cassette consisting of MEL-11/myosin phosphatase and NMY-1/non-muscle myosin is required for coordinated contraction of the spermatheca. In summary, this study answers long-standing questions concerning calcium signaling dynamics in the C. elegans spermatheca and suggests FLN-1 is needed in response to oocyte entry to trigger calcium release and coordinated contraction of the spermathecal tissue.


Assuntos
Sinalização do Cálcio/genética , Cálcio/metabolismo , Proteínas Contráteis/genética , Proteínas dos Microfilamentos/genética , Fosfoinositídeo Fosfolipase C/genética , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Sinalização do Cálcio/fisiologia , Proteínas Contráteis/metabolismo , Feminino , Filaminas , Inositol 1,4,5-Trifosfato/genética , Inositol 1,4,5-Trifosfato/metabolismo , Masculino , Proteínas dos Microfilamentos/metabolismo , Oócitos/metabolismo , Oócitos/fisiologia , Fosfoinositídeo Fosfolipase C/metabolismo , Espermatozoides/metabolismo , Espermatozoides/fisiologia
18.
Proc Natl Acad Sci U S A ; 110(44): 17921-6, 2013 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24127591

RESUMO

Chromatin-based functional genomic analyses and genomewide association studies (GWASs) together implicate enhancers as critical elements influencing gene expression and risk for common diseases. Here, we performed systematic chromatin and transcriptome profiling in human pancreatic islets. Integrated analysis of islet data with those from nine cell types identified specific and significant enrichment of type 2 diabetes and related quantitative trait GWAS variants in islet enhancers. Our integrated chromatin maps reveal that most enhancers are short (median = 0.8 kb). Each cell type also contains a substantial number of more extended (≥ 3 kb) enhancers. Interestingly, these stretch enhancers are often tissue-specific and overlap locus control regions, suggesting that they are important chromatin regulatory beacons. Indeed, we show that (i) tissue specificity of enhancers and nearby gene expression increase with enhancer length; (ii) neighborhoods containing stretch enhancers are enriched for important cell type-specific genes; and (iii) GWAS variants associated with traits relevant to a particular cell type are more enriched in stretch enhancers compared with short enhancers. Reporter constructs containing stretch enhancer sequences exhibited tissue-specific activity in cell culture experiments and in transgenic mice. These results suggest that stretch enhancers are critical chromatin elements for coordinating cell type-specific regulatory programs and that sequence variation in stretch enhancers affects risk of major common human diseases.


Assuntos
Diferenciação Celular/fisiologia , Cromatina/fisiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Elementos Facilitadores Genéticos/genética , Epigenômica/métodos , Regulação da Expressão Gênica/fisiologia , Células Secretoras de Insulina/metabolismo , Animais , Imunoprecipitação da Cromatina , Diabetes Mellitus Tipo 2/genética , Elementos Facilitadores Genéticos/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células Secretoras de Insulina/fisiologia , Luciferases , Camundongos , Camundongos Transgênicos
19.
Sensors (Basel) ; 14(8): 14131-79, 2014 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-25093345

RESUMO

The minimum time search in uncertain domains is a searching task, which appears in real world problems such as natural disasters and sea rescue operations, where a target has to be found, as soon as possible, by a set of sensor-equipped searchers. The automation of this task, where the time to detect the target is critical, can be achieved by new probabilistic techniques that directly minimize the Expected Time (ET) to detect a dynamic target using the observation probability models and actual observations collected by the sensors on board the searchers. The selected technique, described in algorithmic form in this paper for completeness, has only been previously partially tested with an ideal binary detection model, in spite of being designed to deal with complex non-linear/non-differential sensorial models. This paper covers the gap, testing its performance and applicability over different searching tasks with searchers equipped with different complex sensors. The sensorial models under test vary from stepped detection probabilities to continuous/discontinuous differentiable/non-differentiable detection probabilities dependent on distance, orientation, and structured maps. The analysis of the simulated results of several static and dynamic scenarios performed in this paper validates the applicability of the technique with different types of sensor models.


Assuntos
Automação/instrumentação , Incerteza , Algoritmos , Modelos Teóricos , Dinâmica não Linear , Probabilidade
20.
Obes Surg ; 34(4): 1316-1323, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38429485

RESUMO

INTRODUCTION: Laparoscopic sleeve gastrectomy (LSG) is associated with postoperative nausea and vomiting (PONV). We aimed to compare the effects of aprepitant on the incidence of PONV after LSG. METHODS: In this double-blind, randomized controlled trial, the case group received the standard care regimen for PONV (dexamethasone 10 mg, ondansetron 4 mg, and metoclopramide 10 mg) plus prophylactic oral aprepitant 80 mg 1 h preoperatively. The control group received standard care plus a placebo. Comparative analyses using the Rhodes index were performed at 0, 6, 12, and 24 h postoperatively. RESULTS: A total of 400 patients (201 in the aprepitant group and 199 in the placebo group) underwent LSG. The groups were homogeneous. The aprepitant group experienced less PONV: early, 69 (34.3%) vs. 103 (51.7%), p ≤ 0.001; 6 h, 67 (33.3%) vs. 131 (65.8%), p ≤ 0.001; 12 h, 41 (20.4%) vs. 115 (57.8%), p ≤ 0.001; and 24 h, 22 (10.9%) vs. 67 (33.7%), p ≤ 0.001. Fewer patients in the aprepitant group vomited: early, 3 (1.5%) vs. 5 (2.5%), p = 0.020; 6 h, 6 (3%) vs. 18 (9%), p = 0.020; 12 h, 2 (1%) vs. 17 (8.5%), p = 0.006; and 24 h, 1 (0.5%) vs. 6 (3%), p = 0.040. Patients in the aprepitant group required less additional PONV medication: early, 61 (30.3%) vs. 86 (43.2), p = 0.008; 6 h, 7 (3.5%) vs. 34 (17%), p = 0.001; 12 h, 6 (3%) vs. 31 (15.6%), p ≤ 0.001; and 24 h, 5 (2.5%) vs. 11 (5.5%), p ≤ 0.001. CONCLUSIONS: Prophylactic aprepitant improved PONV between 0 h (early) and 24 h postoperatively in patients undergoing LSG.


Assuntos
Antieméticos , Laparoscopia , Obesidade Mórbida , Humanos , Aprepitanto , Antieméticos/uso terapêutico , Náusea e Vômito Pós-Operatórios/tratamento farmacológico , Obesidade Mórbida/cirurgia , Gastrectomia , Método Duplo-Cego
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