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1.
Public Health ; 221: 142-149, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37454404

RESUMO

OBJECTIVES: This study aimed to spatiotemporally analyze the profile of influenza-like illness (ILI) outbreaks in the state of São Paulo, Brazil, between 2020 and 2022. STUDY DESIGN: This was a cross-sectional retrospective study. METHODS: Outbreaks of ILI with final diagnoses of COVID-19, influenza, or other respiratory viruses (ORVs) recorded between January 2020 and November 2022, obtained from the Notifiable Diseases Information System (SINAN NET) Outbreak module, were analyzed. Kernel density estimates and Getis-Ord Gi∗ statistics were performed to identify spatial clusters. RESULTS: A total of 13,314 ILI outbreaks were identified, involving 130,568 cases and 2649 deaths. Of these, 104,399 (80%) were confirmed as COVID-19, 15,861 (12%) were confirmed as ORV, and 10,308 (8%) were confirmed as influenza. The year 2021 had the highest number of outbreaks and cases. Schools recorded the most outbreaks and cases, followed by long-term care facilities for older adults (LTCs). The highest average number of cases per outbreak and the highest attack rates occurred at social gatherings and prisons. Prisoners were three times more likely to contract COVID-19 during outbreaks than people in other institutions. The highest hospitalization and mortality rates for all virus types occurred in the LTC group. The occurrence and intensity of outbreaks were highly heterogeneous among the different institutions after the introduction of new SARS-CoV-2 variants in the state. CONCLUSIONS: ILI outbreaks were not randomly distributed; they clustered in specific areas. Transmissibility varied among different institutions with different responses to the COVID-19 pandemic. These results can be used as a basis for prioritizing actions and allocating resources during future pandemics.


Assuntos
COVID-19 , Influenza Humana , Viroses , Humanos , Idoso , COVID-19/epidemiologia , Influenza Humana/epidemiologia , Pandemias , SARS-CoV-2 , Estudos Retrospectivos , Estudos Transversais , Brasil/epidemiologia , Surtos de Doenças
2.
Ann Oncol ; 33(12): 1250-1268, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36228963

RESUMO

BACKGROUND: The randomized, double-blind OlympiA trial compared 1 year of the oral poly(adenosine diphosphate-ribose) polymerase inhibitor, olaparib, to matching placebo as adjuvant therapy for patients with pathogenic or likely pathogenic variants in germline BRCA1 or BRCA2 (gBRCA1/2pv) and high-risk, human epidermal growth factor receptor 2-negative, early breast cancer (EBC). The first pre-specified interim analysis (IA) previously demonstrated statistically significant improvement in invasive disease-free survival (IDFS) and distant disease-free survival (DDFS). The olaparib group had fewer deaths than the placebo group, but the difference did not reach statistical significance for overall survival (OS). We now report the pre-specified second IA of OS with updates of IDFS, DDFS, and safety. PATIENTS AND METHODS: One thousand eight hundred and thirty-six patients were randomly assigned to olaparib or placebo following (neo)adjuvant chemotherapy, surgery, and radiation therapy if indicated. Endocrine therapy was given concurrently with study medication for hormone receptor-positive cancers. Statistical significance for OS at this IA required P < 0.015. RESULTS: With a median follow-up of 3.5 years, the second IA of OS demonstrated significant improvement in the olaparib group relative to the placebo group [hazard ratio 0.68; 98.5% confidence interval (CI) 0.47-0.97; P = 0.009]. Four-year OS was 89.8% in the olaparib group and 86.4% in the placebo group (Δ 3.4%, 95% CI -0.1% to 6.8%). Four-year IDFS for the olaparib group versus placebo group was 82.7% versus 75.4% (Δ 7.3%, 95% CI 3.0% to 11.5%) and 4-year DDFS was 86.5% versus 79.1% (Δ 7.4%, 95% CI 3.6% to 11.3%), respectively. Subset analyses for OS, IDFS, and DDFS demonstrated benefit across major subgroups. No new safety signals were identified including no new cases of acute myeloid leukemia or myelodysplastic syndrome. CONCLUSION: With 3.5 years of median follow-up, OlympiA demonstrates statistically significant improvement in OS with adjuvant olaparib compared with placebo for gBRCA1/2pv-associated EBC and maintained improvements in the previously reported, statistically significant endpoints of IDFS and DDFS with no new safety signals.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Ftalazinas/efeitos adversos , Células Germinativas/patologia , Proteína BRCA1/genética
4.
Membranes (Basel) ; 11(2)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567608

RESUMO

Wastewater from the oil industry can be considered a dangerous contaminant for the environment and needs to be treated before disposal or re-use. Currently, membrane separation is one of the most used technologies for the treatment of produced water. Therefore, the present work aims to study the process of separating oily water in a module equipped with a ceramic membrane, based on the Eulerian-Eulerian approach and the Shear-Stress Transport (SST k-ω) turbulence model, using the Ansys Fluent® 15.0. The hydrodynamic behavior of the water/oil mixture in the filtration module was evaluated under different conditions of the mass flow rate of the fluid mixture and oil concentration at the entrance, the diameter of the oil particles, and membrane permeability and porosity. It was found that an increase in the feed mass flow rate from 0.5 to 1.5 kg/s significantly influenced transmembrane pressure, that varied from 33.00 to 221.32 kPa. Besides, it was observed that the particle diameter and porosity of the membranes did not influence the performance of the filtration module; it was also verified that increasing the permeability of the membranes, from 3 × 10-15 to 3 × 10-13 m2, caused transmembrane pressure reduction of 22.77%. The greater the average oil concentration at the permeate (from 0.021 to 0.037 kg/m3) and concentrate (from 1.00 to 1.154 kg/m3) outlets, the higher the average flow rate of oil at the permeate outlets. These results showed that the filter separator has good potential for water/oil separation.

5.
Membranes (Basel) ; 10(12)2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33297473

RESUMO

Petroleum has been extracted from oil reservoirs using different techniques. This activity is accompanied for a large amount of water and sometimes mixed with gas. This produced water has a high oil concentration and other toxic chemical compounds, thus, it must be treated to be reused or released to environment according to environmental protection regulations. Currently, ceramic membrane technology has been employed in the wastewater treatment, due to its high benefit-cost ratio. In this sense, this work aims to study the oil-water mixture separation process using a new configuration of tubular ceramic membrane module by computational fluid dynamic (ANSYS Fluent software). The proposed model is composed of mass and linear momentum conservation equations coupled to Darcy's law and SST k-ω turbulence model. Results of the volumetric fraction, pressure, and velocity distribution of the oil and water phases are presented and discussed. The results indicated that the proposed model and new device both have great potential to be used on the water/oil separation process and that the transmembrane pressure remains constant in the axial direction and decreases radially through the membranes, indicating an efficient system that favors the transport of clean water and oil retention.

6.
Membranes (Basel) ; 10(11)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33217918

RESUMO

In the oil industry and academy, the treatment of water contaminated with oil using conventional hydrocyclones and membranes has been an alternative to meet the requirements established by environmental control agencies. However, such equipment is not fully efficient in the treatment of much diluted oily water, with both presenting restrictions in their performance. In this sense, the present work proposes to study the separation process of oily water using a new configuration of hydrocyclone, equipped with a porous ceramic membrane in the conical part's wall (filtering hydrocyclone). For the theoretical study, a Eulerian-Eulerian approach was applied to solve the mass and momentum conservation equations, and the turbulence model, using the computational fluid dynamics technique. The results of the velocity, pressure and volumetric fraction of the involved phases, and the separation performance of the hydrocyclone, are presented, analyzed, and compared with those obtained with a conventional hydrocyclone. The results confirmed the high potential of the proposed equipment to be used in the separation of the water and oil mixture.

7.
Ann Oncol ; 29(4): 872-880, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29360925

RESUMO

Background: Estrogen receptor-positive (ER-positive) metastatic breast cancer is often intractable due to endocrine therapy resistance. Although ESR1 promoter switching events have been associated with endocrine-therapy resistance, recurrent ESR1 fusion proteins have yet to be identified in advanced breast cancer. Patients and methods: To identify genomic structural rearrangements (REs) including gene fusions in acquired resistance, we undertook a multimodal sequencing effort in three breast cancer patient cohorts: (i) mate-pair and/or RNAseq in 6 patient-matched primary-metastatic tumors and 51 metastases, (ii) high coverage (>500×) comprehensive genomic profiling of 287-395 cancer-related genes across 9542 solid tumors (5216 from metastatic disease), and (iii) ultra-high coverage (>5000×) genomic profiling of 62 cancer-related genes in 254 ctDNA samples. In addition to traditional gene fusion detection methods (i.e. discordant reads, split reads), ESR1 REs were detected from targeted sequencing data by applying a novel algorithm (copyshift) that identifies major copy number shifts at rearrangement hotspots. Results: We identify 88 ESR1 REs across 83 unique patients with direct confirmation of 9 ESR1 fusion proteins (including 2 via immunoblot). ESR1 REs are highly enriched in ER-positive, metastatic disease and co-occur with known ESR1 missense alterations, suggestive of polyclonal resistance. Importantly, all fusions result from a breakpoint in or near ESR1 intron 6 and therefore lack an intact ligand binding domain (LBD). In vitro characterization of three fusions reveals ligand-independence and hyperactivity dependent upon the 3' partner gene. Our lower-bound estimate of ESR1 fusions is at least 1% of metastatic solid breast cancers, the prevalence in ctDNA is at least 10× enriched. We postulate this enrichment may represent secondary resistance to more aggressive endocrine therapies applied to patients with ESR1 LBD missense alterations. Conclusions: Collectively, these data indicate that N-terminal ESR1 fusions involving exons 6-7 are a recurrent driver of endocrine therapy resistance and are impervious to ER-targeted therapies.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Neoplasias da Mama/patologia , Receptor alfa de Estrogênio/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação , Metástase Neoplásica , Proteínas Recombinantes de Fusão/genética
8.
BMC Psychiatry ; 16(1): 396, 2016 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-27836011

RESUMO

BACKGROUND: Naturalistic studies can be useful tools to understand how an intervention works in the real clinical practice. This study aims to investigate the outcomes in a naturalistically treated depressed inpatients cohort, who were referred, or not, to unilateral ECT. METHODS: Depressed adults according to MINI admitted in a psychiatric unit were divided in unilateral ECT treated and non-ECT treated. Main outcomes were: depression improvement in Hamilton Rating Scale for Depression (HDRS-17) scores; response (HDRS-17 improvement ≥50 %); remission (HDRS-17 score ≤7); length of hospitalization. RESULTS: Forty-three patients were included in unilateral ECT group and 104 in non-ECT group. No differences of psychotic symptoms, melancholic features or past maniac episode were found between groups. Unilateral ECT group had a mean HDRS-17 score higher than non-ECT group at admission (ECT: 25.05 ± 1.03; non-ECT: 21.61 ± 0.69; p = 0.001), but no significant difference was found at discharge (ECT: 7.70 ± 0.81; non-ECT: 7.40 ± 0.51; p = 0.75). Unilateral ECT group had a larger HDRS-17 score reduction during treatment (ECT: 18.24 ± 1.18; non-ECT:14.20 ± 0.76; p = 0.004). There were no significant differences in response and remission rates between groups. Unilateral ECT group had longer mean duration of hospitalization in days (ECT: 35.48 ± 2.48; non-ECT: 24.57 ± 1.50; p < 0.001), but there were no difference in mean time of treatment (ECT group:27.66 ± 1.95; non-ECT: 24.57 ± 1.50; p = 0.25). CONCLUSIONS: Unilateral high-dose ECT is still a useful treatment option, in the real world clinical practice, to reduce the intensity of depressive symptoms in highly depressed inpatients.


Assuntos
Transtorno Depressivo Maior/terapia , Eletroconvulsoterapia/métodos , Adulto , Antidepressivos/uso terapêutico , Terapia Combinada , Transtorno Depressivo Maior/tratamento farmacológico , Feminino , Humanos , Pacientes Internados , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
9.
Oncogene ; 33(19): 2520-30, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-23770847

RESUMO

The API2-MALT1 fusion oncoprotein is created by the recurrent t(11;18)(q21;q21) chromosomal translocation in mucosa-associated lymphoid tissue (MALT) lymphoma. We identified receptor interacting protein-1 (RIP1) as a novel API2-MALT1-associated protein, and demonstrate that RIP1 is required for API2-MALT1 to stimulate canonical nuclear factor kappa B (NF-κB). API2-MALT1 promotes ubiquitination of RIP1 at lysine (K) 377, which is necessary for full NF-κB activation. Furthermore, we found that TNF receptor-associated factor 2 (TRAF2) recruitment is required for API2-MALT1 to induce RIP1 ubiquitination, NF-κB activation and cellular transformation. Although both TRAF2 and RIP1 interact with the API2 moiety of API2-MALT1, this moiety alone is insufficient to induce RIP1 ubiquitination or activate NF-κB, indicating that API2-MALT1-dependent RIP1 ubiquitination represents a gain of function requiring the concerted actions of both the API2 and MALT1 moieties of the fusion. Intriguingly, constitutive RIP1 ubiquitination was recently demonstrated in several solid tumors, and now our study implicates RIP1 ubiquitination as a critical component of API2-MALT1-dependent lymphomagenesis.


Assuntos
Linfoma de Zona Marginal Tipo Células B/genética , NF-kappa B/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas de Fusão Oncogênica/genética , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais/fisiologia , Fator 2 Associado a Receptor de TNF/metabolismo , Western Blotting , Linhagem Celular Tumoral , Células HEK293 , Humanos , Imunoprecipitação , Linfoma de Zona Marginal Tipo Células B/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Oncogenes , Proteínas de Ligação a RNA/genética , Fator 2 Associado a Receptor de TNF/genética , Transfecção , Ubiquitinação
10.
Oncogene ; 26(38): 5643-54, 2007 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-17334391

RESUMO

Mucosa-associated lymphoid tissue (MALT) lymphoma is the most common extranodal lymphoid neoplasm. Chromosomal translocation t(11;18)(q21,q21) is found in 30% of gastric MALT lymphomas and is associated with a failure to respond to standard treatment and a tendency to disseminate. This translocation generates a chimeric protein composed of N-terminal sequences of Inhibitor of Apoptosis 2 (API2, also known as BIRC3 and cIAP2) fused to C-terminal sequences of MALT1. API2-MALT1 promotes cell survival and proliferation via activation of nuclear factor-kappaB (NF-kappaB). Here, we investigate the mechanism by which the API2 moiety contributes to NF-kappaB stimulation. We find that the API2 moiety mediates oligomerization of API2-MALT1 as well as interaction with tumor necrosis factor receptor-associated factor 2 (TRAF2). Surprisingly, oligomerization does not occur via homotypic interaction; rather, the API2 moiety of one monomer interacts with the MALT1 moiety of another monomer. Further, the specific region of the API2 moiety responsible for mediating oligomerization is distinct from that mediating TRAF2 binding. Although deletion or mutation of the TRAF2 binding site does not inhibit oligomerization, it does lead to dramatically decreased NF-kappaB activation. Deletion of both TRAF2 binding and oligomerization regions results in near-complete loss of NF-kappaB activation. Thus, API2 moiety-mediated heterotypic oligomerization and TRAF2 binding both contribute to maximal API2-MALT1-dependent NF-kappaB stimulation.


Assuntos
Proteínas Inibidoras de Apoptose/fisiologia , NF-kappa B/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Fator 2 Associado a Receptor de TNF/metabolismo , Proteína 3 com Repetições IAP de Baculovírus , Western Blotting , Linhagem Celular , Dimerização , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/genética , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/metabolismo , Humanos , Imunoprecipitação , Proteínas Inibidoras de Apoptose/química , Proteínas Inibidoras de Apoptose/genética , Luciferases/genética , Luciferases/metabolismo , Mutação , NF-kappa B/genética , Proteínas de Fusão Oncogênica/genética , Ligação Proteica/efeitos dos fármacos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fator 2 Associado a Receptor de TNF/química , Fator 2 Associado a Receptor de TNF/genética , Tacrolimo/análogos & derivados , Tacrolimo/farmacologia , Transfecção , Ubiquitina-Proteína Ligases
11.
Am J Pathol ; 159(6): 2239-48, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11733373

RESUMO

Most large bowel cancers are moderately to well-differentiated adenocarcinomas comprised chiefly or entirely of glands lined by tall columnar cells. We have identified a subset of poorly differentiated colon carcinomas with a distinctive histopathological appearance that we term large cell minimally differentiated carcinomas (LCMDCs). These tumors likely include a group of poorly differentiated carcinomas previously described by others as medullary adenocarcinomas. To better understand the pathogenesis of these uncommon neoplasms, we compared molecular features of 15 LCMDCs to those present in 25 differentiated adenocarcinomas (DACs) of the colon. Tumors were examined for alterations commonly seen in typical colorectal carcinomas, including increased p53 and beta-catenin immunoreactivity, K-ras gene mutations, microsatellite instability, and loss of heterozygosity of markers on chromosomes 5q, 17p, and 18q. In addition, tumors were evaluated by immunohistochemistry for CDX2, a homeobox protein whose expression in normal adult tissues is restricted to intestinal and colonic epithelium. Markedly reduced or absent CDX2 expression was noted in 13 of 15 (87%) LCMDCs, whereas only 1 of the 25 (4%) DACs showed reduced CDX2 expression (P < 0.001). Nine of 15 (60%) LCMDCs had the high-frequency microsatellite instability phenotype, but only 2 of 25 (8%) DACs had the high-frequency microsatellite instability phenotype (P = 0.002). Our findings provide support for the hypothesis that the molecular pathogenesis of LCMDCs is distinct from that of most DACs. CDX2 alterations and DNA mismatch repair defects have particularly prominent roles in the development of LCMDCs.


Assuntos
Carcinoma de Células Grandes/patologia , Neoplasias do Colo/patologia , Proteínas de Ligação a DNA , Proteínas de Homeodomínio/biossíntese , Repetições de Microssatélites/genética , Transativadores , Proteínas Adaptadoras de Transdução de Sinal , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fator de Transcrição CDX2 , Carcinoma de Células Grandes/genética , Carcinoma de Células Grandes/metabolismo , Proteínas de Transporte , Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 18/genética , Cromossomos Humanos Par 5/genética , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Proteínas do Citoesqueleto/análise , Feminino , Genes ras/genética , Humanos , Imuno-Histoquímica , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Mutação , Proteínas de Neoplasias/análise , Proteínas Nucleares , Proteínas Proto-Oncogênicas/análise , Proteína Supressora de Tumor p53/análise , beta Catenina
12.
J Biol Chem ; 276(33): 30589-97, 2001 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-11387339

RESUMO

Bcl10 and MALT1, products of distinct chromosomal translocations in mucosa-associated lymphoid tissue lymphoma, cooperate in activating NF-kappaB. Mice lacking Bcl10 demonstrate severe immunodeficiency associated with failure of lymphocytes to activate nuclear factor kappaB (NF-kappaB) in response to antigen receptor stimulation and protein kinase C activation. We characterize Bimp1, a new signaling protein that binds Bcl10 and activates NF-kappaB. Bimp1-mediated NF-kappaB activation requires Bcl10 and IkappaB kinases, indicating that Bimp1 acts upstream of these mediators. Bimp1, Bcl10, and MALT1 form a ternary complex, with Bcl10 bridging the Bimp1/MALT1 interaction. A dominant negative Bimp1 mutant inhibits NF-kappaB activation by anti-CD3 ligation, phorbol ester, and protein kinase C expression. These results suggest that Bimp1 links surface receptor stimulation and protein kinase C activation to Bcl10/MALT1, thus leading to NF-kappaB induction.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Linfoma de Zona Marginal Tipo Células B , NF-kappa B/biossíntese , Proteínas de Neoplasias/fisiologia , Núcleosídeo-Fosfato Quinase/fisiologia , Proteína Quinase C/fisiologia , Sequência de Aminoácidos , Proteína 10 de Linfoma CCL de Células B , Caspases , DNA Complementar/análise , Ativação Enzimática , Guanilato Quinases , Humanos , Quinase I-kappa B , Dados de Sequência Molecular , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa , Proteínas de Neoplasias/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia
13.
J Biol Chem ; 276(22): 19012-9, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11262391

RESUMO

At least two distinct recurrent chromosomal translocations have been implicated in the pathogenesis of MALT lymphoma. The first, t(1;14), results in the transfer of the entire Bcl10 gene to chromosome 14 wherein Bcl10 expression is inappropriately stimulated by the neighboring Ig enhancer. The second, t(11;18), results in the synthesis of a novel fusion protein, API2-MALT1. Until now, no common mechanism of action has been proposed to explain how the products of these seemingly unrelated translocations may contribute to the same malignant process. We show here that Bcl10 and MALT1 form a strong and specific complex within the cell, and that these proteins synergize in the activation of NF-kappaB. The data support a mechanism of action whereby Bcl10 mediates the oligomerization and activation of the MALT1 caspase-like domain. This subsequently activates the IKK complex through an unknown mechanism, setting in motion a cascade of events leading to NF-kappaB induction. Furthermore, the API2-MALT1 fusion protein also strongly activates NF-kappaB and shows dependence upon the same downstream signaling factors. We propose a model whereby both the Bcl10.MALT1 complex and the API2-MALT1 fusion protein activate a common downstream signaling pathway that originates with the oligomerization-dependent activation of the MALT1 caspase-like domain.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Linfoma de Zona Marginal Tipo Células B/genética , Linfoma de Zona Marginal Tipo Células B/metabolismo , NF-kappa B/metabolismo , Proteínas de Neoplasias/metabolismo , Translocação Genética , Proteína 10 de Linfoma CCL de Células B , Western Blotting , Caspases/química , Linhagem Celular , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 18 , Ativação Enzimática , Humanos , Quinase I-kappa B , Modelos Biológicos , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa , Mutação , Proteínas de Neoplasias/genética , Plasmídeos/metabolismo , Testes de Precipitina , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Estrutura Terciária de Proteína , Transdução de Sinais , Transfecção , Células Tumorais Cultivadas
14.
Science ; 289(5481): 950-3, 2000 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-10937998

RESUMO

Wnts are secreted signaling proteins that regulate developmental processes. Here we show that Wnt signaling, likely mediated by Wnt-10b, is a molecular switch that governs adipogenesis. Wnt signaling maintains preadipocytes in an undifferentiated state through inhibition of the adipogenic transcription factors CCAAT/enhancer binding protein alpha (C/EBPalpha) and peroxisome proliferator- activated receptor gamma (PPARgamma). When Wnt signaling in preadipocytes is prevented by overexpression of Axin or dominant-negative TCF4, these cells differentiate into adipocytes. Disruption of Wnt signaling also causes transdifferentiation of myoblasts into adipocytes in vitro, highlighting the importance of this pathway not only in adipocyte differentiation but also in mesodermal cell fate determination.


Assuntos
Adipócitos/citologia , Adipócitos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Repressoras , Transdução de Sinais , Transativadores , Proteínas de Peixe-Zebra , Células 3T3 , Animais , Proteína Axina , Proteínas Estimuladoras de Ligação a CCAAT , Diferenciação Celular , Linhagem da Célula , Proteínas do Citoesqueleto/metabolismo , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Técnicas de Transferência de Genes , Vetores Genéticos , Mesoderma/citologia , Camundongos , Camundongos Nus , Músculos/citologia , Músculos/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas/genética , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/genética , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Retroviridae/genética , Retroviridae/fisiologia , Fatores de Transcrição TCF , Proteína 2 Semelhante ao Fator 7 de Transcrição , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Wnt , beta Catenina
15.
J Biol Chem ; 275(36): 27823-31, 2000 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-10880512

RESUMO

Nod1 is an Apaf-1-like molecule composed of a caspase-recruitment domain (CARD), nucleotide-binding domain, and leucine-rich repeats that associates with the CARD-containing kinase RICK and activates nuclear factor kappaB (NF-kappaB). We show that self-association of Nod1 mediates proximity of RICK and the interaction of RICK with the gamma subunit of the IkappaB kinase (IKKgamma). Similarly, the RICK-related kinase RIP associated via its intermediate region with IKKgamma. A mutant form of IKKgamma deficient in binding to IKKalpha and IKKbeta inhibited NF-kappaB activation induced by RICK or RIP. Enforced oligomerization of RICK or RIP as well as of IKKgamma, IKKalpha, or IKKbeta was sufficient for induction of NF-kappaB activation. Thus, the proximity of RICK, RIP, and IKK complexes may play an important role for NF-kappaB activation during Nod1 oligomerization or trimerization of the tumor necrosis factor alpha receptor.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte/metabolismo , NF-kappa B/metabolismo , Proteínas Quinases/metabolismo , Proteínas/metabolismo , Transcrição Gênica , Animais , Apoptose , Proteínas de Transporte/genética , Linhagem Celular , Fibroblastos/citologia , Fibroblastos/fisiologia , Humanos , Quinase I-kappa B , Camundongos , Proteína Adaptadora de Sinalização NOD1 , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas/genética , Proteína Serina-Treonina Quinase 2 de Interação com Receptor , Proteína Serina-Treonina Quinases de Interação com Receptores , Deleção de Sequência , Transdução de Sinais/fisiologia , Transfecção
16.
Mol Cell Biol ; 15(3): 1747-58, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7532283

RESUMO

The rate of transcription of the hepatic phosphoenolpyruvate carboxykinase (PEPCK) and insulin-like growth factor-binding protein 1 (IGFBP-1) genes is stimulated by glucocorticoids and inhibited by insulin. In both cases, the effect of insulin is dominant, since it suppresses both basal and glucocorticoid-stimulated PEPCK or IGFBP-1 gene transcription. Analyses of both promoters by transfection of PEPCK or IGFBP-1-chloramphenicol acetyltransferase fusion genes into rat hepatoma cells has led to the identification of insulin response sequences (IRSs) in both genes. The core IRS, T(G/A)TTTTG, is the same in both genes, but the PEPCK promoter has a single copy of this element whereas the IGFBP-1 promoter has two copies arranged as an inverted palindrome. The IGFBP-1 IRS and PEPCK IRS both bind the alpha and beta forms of hepatic nuclear factor 3 (HNF-3), although the latter does so with a sixfold-lower relative affinity. Both the PEPCK and the IGFBP-1 IRSs also function as accessory factor binding sites required for the full induction of gene transcription by glucocorticoids. A combination of transient transfection and DNA binding studies suggests that HNF-3 is the accessory factor that supports glucocorticoid-induced gene transcription. In both genes, the HNF-3 binding site overlaps the IRS core motif(s). A model in which insulin is postulated to mediate its negative effect on glucocorticoid-induced PEPCK and IGFBP-1 gene transcription indirectly by inhibiting HNF-3 action is proposed.


Assuntos
Proteínas de Transporte/biossíntese , Proteínas de Ligação a DNA/metabolismo , Dexametasona/farmacologia , Regulação da Expressão Gênica , Insulina/farmacologia , Fígado/metabolismo , Proteínas Nucleares/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/biossíntese , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Carcinoma Hepatocelular , Linhagem Celular , DNA/química , DNA/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fator 3-alfa Nuclear de Hepatócito , Fator 3-beta Nuclear de Hepatócito , Fator 3-gama Nuclear de Hepatócito , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina , Cinética , Neoplasias Hepáticas , Neoplasias Hepáticas Experimentais , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Oligodesoxirribonucleotídeos , Regiões Promotoras Genéticas , Ratos , Receptores de Glucocorticoides/biossíntese , Receptores de Glucocorticoides/fisiologia , Proteínas Recombinantes de Fusão/biossíntese , Sequências Reguladoras de Ácido Nucleico , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas
17.
J Biol Chem ; 269(48): 30419-28, 1994 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-7982956

RESUMO

Adenosine 3',5'-monophosphate (cAMP) stimulates phosphoenolpyruvate carboxykinase (PEPCK) gene transcription, whereas insulin has the opposite effect. In H4IIE cells, the effect of insulin is dominant since it represses cAMP-stimulated transcription. Discrete cis-acting elements in the PEPCK promoter that serve as an insulin response sequence (IRS) and cAMP response element (CRE) have been identified. Here we show that common proteins can bind both elements, since: (i) an almost identical pattern of protein binding is seen when oligonucleotides representing either the IRS or the CRE are used as the labeled probe in a gel retardation assay and (ii) the unlabeled wild-type, but not mutated, CRE oligonucleotide competes for protein binding to the labeled IRS probe, and vice versa. Six homo- and heterodimer complexes interact with these DNA elements; the complexes are composed of three individual protein species: (a) 42-kDa C/EBP alpha, (b) 30-kDa C/EBP alpha, and (c) an unidentified 20-kDa factor termed p20- CRE/IRS Binding Protein (p20-C/IBP). These proteins have a 30-fold greater affinity for the CRE at room temperature, a difference explained by the rapid dissociation rate of protein bound to the IRS, since the association rate of protein binding to both the IRS and CRE is the same. Protease digestion experiments suggest that the proteins bind to the CRE and IRS in different conformations. The IRS and CRE both function in the context of a heterologous promoter to mediate effects of insulin and cAMP, respectively, but, although the PEPCK IRS and CRE bind common proteins, the PEPCK CRE is not a functional IRS and the PEPCK IRS is not a functional CRE.


Assuntos
AMP Cíclico/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Insulina/farmacologia , Proteínas Nucleares/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Regiões Promotoras Genéticas , Transdução de Sinais , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Proteínas Estimuladoras de Ligação a CCAAT , Carcinoma Hepatocelular , Linhagem Celular , Núcleo Celular/metabolismo , DNA/química , DNA/metabolismo , Proteínas de Ligação a DNA/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Humanos , Cinética , Neoplasias Hepáticas , Neoplasias Hepáticas Experimentais , Dados de Sequência Molecular , Fosfoenolpiruvato Carboxiquinase (GTP)/biossíntese , Fosfoenolpiruvato Carboxiquinase (GTP)/isolamento & purificação , Biossíntese de Proteínas , Ratos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas
19.
Mol Cell Biol ; 12(12): 5527-35, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1333043

RESUMO

The accessory factor 1 (AF1) element is an upstream transcriptional control region that plays a role in the response of the phosphoenolpyruvate carboxykinase (PEPCK) gene to both glucocorticoids and retinoic acid. We demonstrate here that retinoic acid receptor alpha (RAR alpha) binds to a sequence within the AF1 element, TGACCT (site B), that is a consensus retinoic acid response element (RARE) half-site. A similar DNA sequence, TGGCCG (site C), located 1 bp downstream of site B, is not involved in the binding of RAR alpha monomers or dimers but is required for the constitution of a functional RARE. Site C is also required for the formation of a complex involving RAR alpha and a liver nuclear factor designated CR, for coregulator. Mutational analysis of the AF1 element shows that the RAR alpha/CR complex is the trans-acting unit that mediates the retinoic acid response of the PEPCK gene. Another member of the retinoid receptor family, retinoid X receptor alpha (RXR alpha), can also form a complex with RAR alpha and the AF1 element. Several observations, including the observation that RXR alpha antibody interacts with CR, indicate that RXR alpha and CR are identical or closely related proteins. Through RXR alpha forms a complex with RAR alpha and the AF1 element, we demonstrate that the AF1 element is functionally distinguishable from a retinoid X response element. Taken together, our results show that the AF1 element contains an RARE that mediates a retinoic acid response by binding an RAR alpha/coregulator complex; this coregulator is presumably RXR alpha.


Assuntos
Proteínas de Transporte/metabolismo , Regulação Enzimológica da Expressão Gênica , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Tretinoína/metabolismo , Sequência de Bases , Sítios de Ligação , Ligação Competitiva , DNA , Ativação Enzimática , Metilação , Dados de Sequência Molecular , Mutação , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Plasmídeos , Receptores do Ácido Retinoico , Sequências Reguladoras de Ácido Nucleico
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