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1.
Science ; 379(6634): eabn8671, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36137011

RESUMO

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

2.
Braz J Med Biol Res ; 55: e11612, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35137850

RESUMO

Anoikis is a type of apoptosis that occurs in response to the loss of adhesion to the extracellular matrix (ECM). Anoikis resistance is a critical mechanism in cancer and contributes to tumor metastasis. Nitric oxide (NO) is frequently upregulated in the tumor area and is considered an important player in cancer metastasis. The aim of this study was to evaluate the effect of NO on adhesiveness, invasiveness, and migration of anoikis-resistant endothelial cells. Here, we report that anoikis-resistant endothelial cells overexpress endothelial nitric oxide synthase. The inhibition of NO release in anoikis-resistant endothelial cells was able to decrease adhesiveness to fibronectin, laminin, and collagen IV. This was accompanied by an increase in cell invasiveness and migration. Furthermore, anoikis-resistant cell lines displayed a decrease in fibronectin and collagen IV protein expression after L-NAME treatment. These alterations in adhesiveness and invasiveness were the consequence of MMP-2 up-regulation observed after NO release inhibition. The decrease in NO levels was able to down-regulate the activating transcription factor 3 (ATF3) protein expression. ATF3 represses MMP-2 gene expression by antagonizing p53-dependent trans-activation of the MMP-2 promoter. We speculate that the increased release of NO by anoikis-resistant endothelial cells acted as a response to restrict the MMP-2 action, interfering in MMP-2 gene expression via ATF3 regulation. The up-regulation of nitric oxide by anoikis-resistant endothelial cells is an important response to restrict tumorigenic behavior. Without this mechanism, invasiveness and migration potential would be even higher, as shown after L-NAME treatment.


Assuntos
Anoikis , Células Endoteliais , Adesividade , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Humanos , Invasividade Neoplásica , Óxido Nítrico/metabolismo , Regulação para Cima
3.
Science ; 375(6584): 1011-1016, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35143255

RESUMO

The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. The mission performed two landing operations to collect samples of surface and subsurface material, the latter exposed by an artificial impact. We present images of the second touchdown site, finding that ejecta from the impact crater was present at the sample location. Surface pebbles at both landing sites show morphological variations ranging from rugged to smooth, similar to Ryugu's boulders, and shapes from quasi-spherical to flattened. The samples were returned to Earth on 6 December 2020. We describe the morphology of >5 grams of returned pebbles and sand. Their diverse color, shape, and structure are consistent with the observed materials of Ryugu; we conclude that they are a representative sample of the asteroid.

4.
Braz. j. med. biol. res ; 55: e11612, 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1360231

RESUMO

Anoikis is a type of apoptosis that occurs in response to the loss of adhesion to the extracellular matrix (ECM). Anoikis resistance is a critical mechanism in cancer and contributes to tumor metastasis. Nitric oxide (NO) is frequently upregulated in the tumor area and is considered an important player in cancer metastasis. The aim of this study was to evaluate the effect of NO on adhesiveness, invasiveness, and migration of anoikis-resistant endothelial cells. Here, we report that anoikis-resistant endothelial cells overexpress endothelial nitric oxide synthase. The inhibition of NO release in anoikis-resistant endothelial cells was able to decrease adhesiveness to fibronectin, laminin, and collagen IV. This was accompanied by an increase in cell invasiveness and migration. Furthermore, anoikis-resistant cell lines displayed a decrease in fibronectin and collagen IV protein expression after L-NAME treatment. These alterations in adhesiveness and invasiveness were the consequence of MMP-2 up-regulation observed after NO release inhibition. The decrease in NO levels was able to down-regulate the activating transcription factor 3 (ATF3) protein expression. ATF3 represses MMP-2 gene expression by antagonizing p53-dependent trans-activation of the MMP-2 promoter. We speculate that the increased release of NO by anoikis-resistant endothelial cells acted as a response to restrict the MMP-2 action, interfering in MMP-2 gene expression via ATF3 regulation. The up-regulation of nitric oxide by anoikis-resistant endothelial cells is an important response to restrict tumorigenic behavior. Without this mechanism, invasiveness and migration potential would be even higher, as shown after L-NAME treatment.

5.
Clin. transl. oncol. (Print) ; 23(12): 2474-2481, dec. 2021.
Artigo em Inglês | IBECS | ID: ibc-224104

RESUMO

Purpose The objectives of this study were to clarify whether resection of primary tumor in the extremities for patients with metastatic soft-tissue sarcoma (STS) improves survival, and to clarify patient groups for whom primary tumor resection should be considered. Methods/patients Using the surveillance, epidemiology, and end results database, we identified 1453 patients with metastatic STS of the extremities at initial presentation between 1983 and 2016. Of these 1453 patients, 898 patients underwent primary tumor resection (Surgery group), and 555 patients did not (No-surgery group). Results After adjusting for patient background by propensity score matching, a total of 804 patients were included for analysis. Patients in the Surgery group showed improved survival (cancer-specific survival (CSS) hazard ratio (HR) = 0.59, 95% confidence interval (CI) 0.50–0.71 overall survival rate (OS) HR = 0.60, 95% CI 0.51–0.70). In subclass analysis, patients with high-grade STS, undifferentiated pleomorphic sarcoma, leiomyosarcoma, or synovial sarcoma showed improved survival in the Surgery group (high grade—CSS HR = 0.57, 95% CI 0.45–0.72, OS HR = 0.58, 95% CI 0.48–0.71; undifferentiated pleomorphic sarcoma—CSS HR = 0.60, 95% CI 0.42–0.84, OS HR = 0.61, 95% CI 0.46–0.82; leiomyosarcoma—CSS HR = 0.50, 95% CI 0.33–0.75, OS HR = 0.50, 95% CI 0.35–0.72; synovial sarcoma—CSS HR = 0.46, 95% CI 0.31–0.68, OS HR = 0.43, 95% CI 0.30–0.62). Conclusions Our results indicated that primary tumor resection in metastatic STS exerts positive impacts on survival. Further clinical research is needed to confirm these results (AU)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Extremidades/cirurgia , Programa de SEER , Sarcoma/mortalidade , Análise de Sobrevida , Estados Unidos/epidemiologia , Seguimentos , Sarcoma/secundário , Sarcoma/cirurgia , Prognóstico
6.
Clin Transl Oncol ; 23(12): 2474-2481, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34060011

RESUMO

PURPOSE: The objectives of this study were to clarify whether resection of primary tumor in the extremities for patients with metastatic soft-tissue sarcoma (STS) improves survival, and to clarify patient groups for whom primary tumor resection should be considered. METHODS/PATIENTS: Using the surveillance, epidemiology, and end results database, we identified 1453 patients with metastatic STS of the extremities at initial presentation between 1983 and 2016. Of these 1453 patients, 898 patients underwent primary tumor resection (Surgery group), and 555 patients did not (No-surgery group). RESULTS: After adjusting for patient background by propensity score matching, a total of 804 patients were included for analysis. Patients in the Surgery group showed improved survival (cancer-specific survival (CSS) hazard ratio (HR) = 0.59, 95% confidence interval (CI) 0.50-0.71 overall survival rate (OS) HR = 0.60, 95% CI 0.51-0.70). In subclass analysis, patients with high-grade STS, undifferentiated pleomorphic sarcoma, leiomyosarcoma, or synovial sarcoma showed improved survival in the Surgery group (high grade-CSS HR = 0.57, 95% CI 0.45-0.72, OS HR = 0.58, 95% CI 0.48-0.71; undifferentiated pleomorphic sarcoma-CSS HR = 0.60, 95% CI 0.42-0.84, OS HR = 0.61, 95% CI 0.46-0.82; leiomyosarcoma-CSS HR = 0.50, 95% CI 0.33-0.75, OS HR = 0.50, 95% CI 0.35-0.72; synovial sarcoma-CSS HR = 0.46, 95% CI 0.31-0.68, OS HR = 0.43, 95% CI 0.30-0.62). CONCLUSIONS: Our results indicated that primary tumor resection in metastatic STS exerts positive impacts on survival. Further clinical research is needed to confirm these results.


Assuntos
Extremidades/cirurgia , Programa de SEER/estatística & dados numéricos , Sarcoma/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Sarcoma/secundário , Sarcoma/cirurgia , Taxa de Sobrevida , Estados Unidos/epidemiologia
7.
Science ; 368(6491): 654-659, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32381723

RESUMO

The near-Earth asteroid (162173) Ryugu is thought to be a primitive carbonaceous object that contains hydrated minerals and organic molecules. We report sample collection from Ryugu's surface by the Hayabusa2 spacecraft on 21 February 2019. Touchdown images and global observations of surface colors are used to investigate the stratigraphy of the surface around the sample location and across Ryugu. Latitudinal color variations suggest the reddening of exposed surface material by solar heating and/or space weathering. Immediately after touchdown, Hayabusa2's thrusters disturbed dark, fine grains that originate from the redder materials. The stratigraphic relationship between identified craters and the redder material indicates that surface reddening occurred over a short period of time. We suggest that Ryugu previously experienced an orbital excursion near the Sun.

8.
Science ; 368(6486): 67-71, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32193363

RESUMO

The Hayabusa2 spacecraft investigated the small asteroid Ryugu, which has a rubble-pile structure. We describe an impact experiment on Ryugu using Hayabusa2's Small Carry-on Impactor. The impact produced an artificial crater with a diameter >10 meters, which has a semicircular shape, an elevated rim, and a central pit. Images of the impact and resulting ejecta were recorded by the Deployable CAMera 3 for >8 minutes, showing the growth of an ejecta curtain (the outer edge of the ejecta) and deposition of ejecta onto the surface. The ejecta curtain was asymmetric and heterogeneous and it never fully detached from the surface. The crater formed in the gravity-dominated regime; in other words, crater growth was limited by gravity not surface strength. We discuss implications for Ryugu's surface age.

9.
Science ; 364(6437): 272-275, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30890589

RESUMO

The near-Earth asteroid 162173 Ryugu, the target of the Hayabusa2 sample-return mission, is thought to be a primitive carbonaceous object. We report reflectance spectra of Ryugu's surface acquired with the Near-Infrared Spectrometer (NIRS3) on Hayabusa2, to provide direct measurements of the surface composition and geological context for the returned samples. A weak, narrow absorption feature centered at 2.72 micrometers was detected across the entire observed surface, indicating that hydroxyl (OH)-bearing minerals are ubiquitous there. The intensity of the OH feature and low albedo are similar to thermally and/or shock-metamorphosed carbonaceous chondrite meteorites. There are few variations in the OH-band position, which is consistent with Ryugu being a compositionally homogeneous rubble-pile object generated from impact fragments of an undifferentiated aqueously altered parent body.

10.
Science ; 364(6437): 268-272, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30890588

RESUMO

The Hayabusa2 spacecraft arrived at the near-Earth carbonaceous asteroid 162173 Ryugu in 2018. We present Hayabusa2 observations of Ryugu's shape, mass, and geomorphology. Ryugu has an oblate "spinning top" shape, with a prominent circular equatorial ridge. Its bulk density, 1.19 ± 0.02 grams per cubic centimeter, indicates a high-porosity (>50%) interior. Large surface boulders suggest a rubble-pile structure. Surface slope analysis shows Ryugu's shape may have been produced from having once spun at twice the current rate. Coupled with the observed global material homogeneity, this suggests that Ryugu was reshaped by centrifugally induced deformation during a period of rapid rotation. From these remote-sensing investigations, we identified a suitable sample collection site on the equatorial ridge.

11.
Science ; 364(6437): 252, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30890587

RESUMO

The near-Earth carbonaceous asteroid 162173 Ryugu is thought to have been produced from a parent body that contained water ice and organic molecules. The Hayabusa2 spacecraft has obtained global multicolor images of Ryugu. Geomorphological features present include a circum-equatorial ridge, east-west dichotomy, high boulder abundances across the entire surface, and impact craters. Age estimates from the craters indicate a resurfacing age of [Formula: see text] years for the top 1-meter layer. Ryugu is among the darkest known bodies in the Solar System. The high abundance and spectral properties of boulders are consistent with moderately dehydrated materials, analogous to thermally metamorphosed meteorites found on Earth. The general uniformity in color across Ryugu's surface supports partial dehydration due to internal heating of the asteroid's parent body.

12.
Osteoarthritis Cartilage ; 27(2): 314-325, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30471358

RESUMO

OBJECTIVE: Gangliosides, ubiquitously existing membrane components that modulate transmembrane signaling and mediate cell-to-cell and cell-to-matrix interactions, are key molecules of inflammatory and neurological disorders. However, the functions of gangliosides in the cartilage degradation process remain unclear. We investigated the functional role of gangliosides in cartilage metabolism related to osteoarthritis (OA) pathogenesis. DESIGN: We generated knockout (KO) mice by targeting the ß1, 4-N-acetylgalactosaminyltransferase (GalNAcT) gene, which encodes an enzyme of major gangliosides synthesis, and the GD3 synthase (GD3S) gene, which encodes an enzyme of partial gangliosides synthesis. In vivo OA and in vitro cartilage degradation models were used to evaluate the effect of gangliosides on the cartilage degradation process. RESULTS: The GalNAcT and GD3S KO mice developed and grew normally; nevertheless, OA changes in these mice were enhanced with aging. The GalNAcT KO mice showed significantly enhanced OA progression compared to GD3S mice in vivo. Both GalNAcT and GD3S KO mice showed severe IL-1α-induced cartilage degradation ex vivo. Phosphorylation of MAPKs was enhanced in both GalNAcT and GD3S KOs after IL-1α stimulation. Gangliosides modulated by GalNAcT or GD3S rescued an increase of MMP-13 induced by IL-1α in mice lacking GalNAcT or GD3S after exogenous replenishment in vitro. CONCLUSION: These data show that the deletion of gangliosides in mice enhanced OA development. Moreover, the gangliosides modulated by GalNAcT are important for cartilage metabolism, suggesting that GalNAcT is a potential target molecule for the development of novel OA treatments.


Assuntos
Artrite Experimental/metabolismo , Cartilagem Articular/metabolismo , Gangliosídeos/fisiologia , Osteoartrite/metabolismo , Envelhecimento/fisiologia , Animais , Artrite Experimental/patologia , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Progressão da Doença , Gangliosídeos/deficiência , Gangliosídeos/farmacologia , Deleção de Genes , Crescimento/genética , Interleucina-1alfa/antagonistas & inibidores , Interleucina-1alfa/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Metaloproteinase 13 da Matriz/biossíntese , Camundongos Knockout , N-Acetilgalactosaminiltransferases/deficiência , N-Acetilgalactosaminiltransferases/genética , N-Acetilgalactosaminiltransferases/fisiologia , Óxido Nítrico/metabolismo , Osteoartrite/patologia , Sialiltransferases/deficiência , Sialiltransferases/genética , Sialiltransferases/fisiologia , Técnicas de Cultura de Tecidos , Regulação para Cima/fisiologia
13.
Clin Microbiol Infect ; 24(12): 1305-1310, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29496597

RESUMO

OBJECTIVES: Antimicrobial resistance (AMR) is a priority for surveillance in bacterial infections. For leprosy, AMR has not been assessed because Mycobacterium leprae does not grow in vitro. We aim to obtain AMR data using molecular detection of resistance genes and to conduct a prospective open survey of resistance to antileprosy drugs in countries where leprosy is endemic through a WHO surveillance network. METHODS: From 2009 to 2015, multi-bacillary leprosy cases at sentinel sites of 19 countries were studied for resistance to rifampicin, dapsone and ofloxacin by PCR sequencing of the drug-resistance-determining regions of the genes rpoB, folP1 and gyrA. RESULTS: Among 1932 (1143 relapse and 789 new) cases studied, 154 (8.0%) M. leprae strains were found with mutations conferring resistance showing 182 resistance traits (74 for rifampicin, 87 for dapsone and 21 for ofloxacin). Twenty cases showed rifampicin and dapsone resistance, four showed ofloxacin and dapsone resistance, but no cases were resistant to rifampicin and ofloxacin. Rifampicin resistance was observed among relapse (58/1143, 5.1%) and new (16/789, 2.0%) cases in 12 countries. India, Brazil and Colombia reported more than five rifampicin-resistant cases. CONCLUSIONS: This is the first study reporting global data on AMR in leprosy. Rifampicin resistance emerged, stressing the need for expansion of surveillance. This is also a call for vigilance on the global use of antimicrobial agents, because ofloxacin resistance probably developed in relation to the general intake of antibiotics for other infections as it is not part of the multidrug combination used to treat leprosy.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana/genética , Hanseníase/epidemiologia , Mycobacterium leprae/efeitos dos fármacos , Mycobacterium leprae/genética , Antibacterianos/efeitos adversos , Proteínas de Bactérias/genética , Biópsia por Agulha , Brasil/epidemiologia , Colômbia/epidemiologia , DNA Girase/genética , Dapsona/uso terapêutico , Doenças Endêmicas/estatística & dados numéricos , Monitoramento Epidemiológico , Saúde Global , Humanos , Índia/epidemiologia , Hanseníase/diagnóstico , Hanseníase/tratamento farmacológico , Hanseníase/microbiologia , Testes de Sensibilidade Microbiana , Mutação , Ofloxacino/uso terapêutico , Reação em Cadeia da Polimerase , Estudos Prospectivos , Recidiva , Rifampina/uso terapêutico , Vigilância de Evento Sentinela , Pele/microbiologia , Pele/patologia , Inquéritos e Questionários , Organização Mundial da Saúde
15.
Oncogene ; 36(31): 4481-4497, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28368411

RESUMO

We previously reported that PU.1 is downregulated in the majority of myeloma cell lines and primary myeloma cells of certain myeloma patients, and conditional expression of PU.1 in such myeloma cell lines induced cell cycle arrest and apoptosis. We found downregulation of IRF4 protein in the U266 myeloma cell line following induction of PU.1. Previous studies reported that knockdown of IRF4 in myeloma cell lines induces apoptosis, prompting us to further investigate the role of IRF4 downregulation in PU.1-induced cell cycle arrest and apoptosis in myeloma cells. PU.1 induced downregulation of IRF4 at the protein level, cell cycle arrest and apoptosis in six myeloma cell lines. Chromatin immunoprecipitation (ChIP) revealed that PU.1 directly binds to the IRF4 promoter, whereas a reporter assay showed that PU.1 may suppress IRF4 promoter activity. Stable expression of IRF4 in myeloma cells expressing PU.1 partially rescued the cells from apoptosis induced by PU.1. As it was reported that IRF4 directly binds to the IRF7 promoter and downregulates its expression in activated B cell-like subtype of diffuse large B cell lymphoma cells, we performed ChIP assays and found that IRF4 directly binds the IRF7 promoter in myeloma cells. It is known that IRF7 positively upregulates interferon-ß (IFNß) and induces apoptosis in many cell types. Binding of IRF4 to the IRF7 promoter decreased following PU.1 induction, accompanied by downregulation of IRF4 protein expression. Knockdown of IRF7 protected PU.1-expressing myeloma cells from apoptosis. Furthermore, IFNß, which is a downstream target of IRF7, was upregulated in myeloma cells along with IRF7 after PU.1 induction. Finally, we evaluated the mRNA expression levels of PU.1, IRF4 and IRF7 in primary myeloma cells from patients and found that PU.1 and IRF7 were strongly downregulated in contrast to the high expression levels of IRF4. These data strongly suggest that PU.1-induced apoptosis in myeloma cells is associated with IRF4 downregulation and subsequent IRF7 upregulation.


Assuntos
Fatores Reguladores de Interferon/fisiologia , Mieloma Múltiplo/genética , Proteínas Proto-Oncogênicas/fisiologia , Transativadores/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Apoptose , Humanos , Fator Regulador 7 de Interferon/genética , Fatores Reguladores de Interferon/genética , Interferon beta/biossíntese , Mieloma Múltiplo/patologia , Regiões Promotoras Genéticas , Transcrição Gênica , Células U937
16.
Ann Rheum Dis ; 76(4): 632-638, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27658678

RESUMO

OBJECTIVES: The treat-to-target (T2T) concept has been applied successfully in several inflammatory rheumatic diseases. Gout is a chronic disease with a high burden of pain and inflammation. Because the pathogenesis of gout is strongly related to serum urate levels, gout may be an ideal disease in which to apply a T2T approach. Our aim was to develop international T2T recommendations for patients with gout. METHODS: A committee of experts with experience in gout agreed upon potential targets and outcomes, which was the basis for the systematic literature search. Eleven rheumatologists, one cardiologist, one nephrologist, one general practitioner and one patient met in October 2015 to develop T2T recommendations based on the available scientific evidence. Levels of evidence, strength of recommendations and levels of agreement were derived. RESULTS: Although no randomised trial was identified in which a comparison with standard treatment or an evaluation of a T2T approach had been performed in patients with gout, indirect evidence was provided to focus on targets such as normalisation of serum urate levels. The expert group developed four overarching principles and nine T2T recommendations. They considered dissolution of crystals and prevention of flares to be fundamental; patient education, ensuring adherence to medications and monitoring of serum urate levels were also considered to be of major importance. CONCLUSIONS: This is the first application of the T2T approach developed for gout. Since no publication reports a trial comparing treatment strategies for gout, highly credible overarching principles and level D expert recommendations were created and agreed upon.


Assuntos
Gota/sangue , Gota/tratamento farmacológico , Ácido Úrico/sangue , Doença Crônica , Guias como Assunto , Humanos , Rim/fisiopatologia , Estilo de Vida , Adesão à Medicação , Planejamento de Assistência ao Paciente , Educação de Pacientes como Assunto , Participação do Paciente , Literatura de Revisão como Assunto
17.
Chemosphere ; 153: 237-43, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27016820

RESUMO

TiO2-encapsulated H-ZSM photocatalysts were prepared by physical mixing of TiO2 and zeolites. Pt was immobilized on the surface of the TiO2-encapsulated zeolite (H-ZSM) catalysts by a simple photochemical reduction method. Different weight ratios of both TiO2 and Pt were hybridized with H-ZSM and the catalytic performance of the prepared catalysts was investigated for 2-propanol oxidation in liquid phase and acetaldehyde in gas phase reaction. Around 5-10 wt% TiO2-encapsulated H-ZSM catalysts was found to be optimal amount for the effective oxidation of the organics. Prior to light irradiation, Pt-TiO2-H-ZSM showed considerable amount of catalytic degradation of 2-propanol in the dark, forming acetone as an intermediate. In this study, Pt has played a major and important role on the total oxidation of 2-propanol as well as acetaldehyde. As a result, no residual organics were present in the pores of the zeolites. The catalysts could be reused more than three times without losing their catalytic activity in both phases. The Pt-TiO2-H-ZSM photocatalysts could overcome the problem of strong adsorption of organics in the zeolite pores (after the reaction). Thus, Pt-TiO2-H-ZSM can be used as a potential catalyst for both liquid and gas phase oxidation of organic pollutants.


Assuntos
2-Propanol/química , Acetaldeído/química , Recuperação e Remediação Ambiental/métodos , Titânio/química , Poluentes Químicos da Água/química , Zeolitas/química , Adsorção , Catálise , Oxirredução , Platina/química
18.
Nihon Hansenbyo Gakkai Zasshi ; 84(3): 107, 2016 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-27008821
19.
Oncogene ; 35(34): 4509-17, 2016 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-26804169

RESUMO

Human T-cell leukemia virus type 1 (HTLV-1) is an oncogenic retrovirus that induces a fatal T-cell malignancy, adult T-cell leukemia (ATL). Among several regulatory/accessory genes in HTLV-1, HTLV-1 bZIP factor (HBZ) is the only viral gene constitutively expressed in infected cells. Our previous study showed that HBZ functions in two different molecular forms, HBZ protein and HBZ RNA. In this study, we show that HBZ protein targets retinoblastoma protein (Rb), which is a critical tumor suppressor in many types of cancers. HBZ protein interacts with the Rb/E2F-1 complex and activates the transcription of E2F-target genes associated with cell cycle progression and apoptosis. Mouse primary CD4(+) T cells transduced with HBZ show accelerated G1/S transition and apoptosis, and importantly, T cells from HBZ transgenic (HBZ-Tg) mice also demonstrate enhanced cell proliferation and apoptosis. To evaluate the functions of HBZ protein alone in vivo, we generated a new transgenic mouse strain that expresses HBZ mRNA altered by silent mutations but encoding intact protein. In these mice, the numbers of effector/memory and Foxp3(+) T cells were increased, and genes associated with proliferation and apoptosis were upregulated. This study shows that HBZ protein promotes cell proliferation and apoptosis in primary CD4(+) T cells through activation of the Rb/E2F pathway, and that HBZ protein also confers onto CD4(+) T-cell immunophenotype similar to those of ATL cells, suggesting that HBZ protein has important roles in dysregulation of CD4(+) T cells infected with HTLV-1.


Assuntos
Apoptose , Fatores de Transcrição de Zíper de Leucina Básica/fisiologia , Linfócitos T CD4-Positivos/patologia , Proteína do Retinoblastoma/fisiologia , Proteínas dos Retroviridae/fisiologia , Transdução de Sinais/fisiologia , Animais , Linfócitos T CD4-Positivos/virologia , Ciclo Celular , Proliferação de Células , Células Cultivadas , Fator de Transcrição E2F1/fisiologia , Histona Desacetilases/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteína Supressora de Tumor p53/fisiologia
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