Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
J Environ Manage ; 277: 111399, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33059324

RESUMO

Functionalized ZnAl layered double hydroxide based photocatalyst was obtained by the addition of sodium dodecyl sulfate (SDS) during the synthesis by the coprecipitation method, and further calcination at 400 °C. Bare and modified materials were characterized by X-ray diffraction, nitrogen adsorption-desorption, IR, UV-Vis, EPR and XPS spectroscopies, SEM and HRTEM. The synthesized material was evaluated in the photodegradation of phenol in a 40 ppm aqueous solution (4.25 × 10-4 mol of phenol/L), under UV light irradiation. An increasing in the degradation of phenol from 62 to 95%, and from 62 to 82% in the mineralization of phenol was obtained using SDS functionalized ZnAl LDH, in comparison with the unmodified material. This increase could be attributed to the presence of sulfate radicals, confirmed by the EPR study.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Hidróxidos , Fotólise
2.
J Environ Manage ; 232: 305-309, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30496959

RESUMO

In this work, we demonstrate for the first time that Thermal Lens Microscopy technique (TLM) can be applied to monitor the dynamics of a photocatalytic process in-situ. The photocatalytic reduction of hexavalent chromium -Cr(VI)- in aqueous solution using CdS and irradiated with visible light is monitored by TLM. Since the values of Cr(VI) concentration obtained after the photocatalytic process were close to those imposed by the international regulations for drinking water, the use of TLM allowed its measurement with a better reliability than with UV spectroscopy, usually used in this kind of analysis.


Assuntos
Microscopia , Águas Residuárias , Catálise , Cromo , Reprodutibilidade dos Testes
4.
Br J Cancer ; 109(4): 950-6, 2013 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-23880823

RESUMO

BACKGROUND: Evidence increasingly supports that prostate cancer is initiated by the malignant transformation of stem cells (SCs). Furthermore, many SC-signalling pathways are shown to be shared in prostate cancer. Therefore, we planned transcriptome characterisation of adult prostate SCs as a strategy to consider new targets for cancer treatment. METHODS: Intuitive pathway analysis was used for putative target discovery in 12 matched selections of human prostate SCs, transiently amplifying cells and terminally differentiated cells. These were pooled into three groups according to the stage of differentiation for mRNA microarray analysis. Targets identified were validated using uncultured primary tissue (n=12), functional models of prostate cancer and a tissue microarray consisting of benign (n=42) and malignant prostate (n=223). RESULTS: A deficiency in class 1 UDP glucuronosyltransferase (UGT) enzymes (UGT1A) was identified in prostate SCs, which are involved in androgen catabolism. Class 1 UGT enzyme expression was also downregulated in cancer SCs and during progression to metastatic castration-resistant prostate cancer (CRPC). Reduction of UGT1A expression in vitro was seen to improve cell survival and increase androgen receptor (AR) activity, as shown by upregulation of prostate-specific antigen expression. INTERPRETATION: Inactivation of intracellular androgen catabolism represents a novel mechanism to maintain AR activity during CRPC.


Assuntos
Células-Tronco Adultas/enzimologia , Regulação Neoplásica da Expressão Gênica , Glucuronosiltransferase/genética , Células-Tronco Neoplásicas/enzimologia , Próstata/enzimologia , Neoplasias da Próstata/enzimologia , RNA Mensageiro/análise , Androgênios/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação para Baixo , Perfilação da Expressão Gênica , Glucuronosiltransferase/metabolismo , Humanos , Calicreínas/metabolismo , Masculino , Próstata/citologia , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores Androgênicos/metabolismo , Transcriptoma , Regulação para Cima
5.
Bioresour Technol ; 274: 321-328, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30529479

RESUMO

The aim of this work was to use an inexpensive technique, such as the most probable number, MPN to quantitatively and qualitatively examine microbial groups in anaerobic digestion, AD of cattle manure, CM. Different diluents and mixing ratios were evaluated in 100 mL reactors using biomethane potential, BMP, as output variable. MPN tests were performed to samples from a 23 L tank and 6.5 m3 low-cost tubular digester, LCTD. To monitor LCTD stability, volatile solids, VS, specific methanogenic activity, SMA, pH, volatile fatty acids, VFA, and chemical oxygen demand, COD were measured. Microbial characterization highlighted the optimal population essential to initiate the anaerobic digestion process. Bacteria domain were predominant over Archaea, with average abundance values of 78% and 22%, respectively. SMA of 0.0486 g COD g-1 SV d-1 was obtained at laboratory-scale and LCTD reached 83% of this value. Conditions selected are cost-effective to establish a biodigester in rural areas.


Assuntos
Reatores Biológicos , Anaerobiose , Animais , Bactérias Anaeróbias , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos/microbiologia , Bovinos , Fenômenos Químicos , Euryarchaeota , Ácidos Graxos Voláteis/biossíntese , Esterco , Metano/biossíntese
6.
Endocr Pathol ; 12(2): 113-23, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11579677

RESUMO

RET/PTC oncogene expression is restricted to papillary thyroid carcinomas (PTC). At least three forms of this oncogene have been described. These are generated by the rearrangement of the 5'-terminal region of different expressed genes with the tyrosine-kinase (TK) domain of the ret proto-oncogene. Several studies showing the correlation between the expression of this oncogene, clinical outcome, and histological subtypes have been published. Thirty-five paraffin-embedded PTC samples from patients without a history of radiation exposure were studied. Immunohistochemistry (IHC) and in situ hybridization (ISH) were used to determine a possible correlation between RET activation, clinical outcome, and tumor subtype. Almost half of the studied cases presented with tumoral extension or metastases. Ret gene transcripts and protein were found in all PTC variants as well as in their corresponding metastases. In contrast, none of the follicular adenomas, goiters, or normal follicular cells from the thyroid gland showed evidence of ret activation. We observed a high frequency of ret expression in PTCs, suggesting that ret activation is a common event in nonradiation-related PTC from Mexican patients.


Assuntos
Carcinoma Papilar/enzimologia , Proteínas de Drosophila , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Neoplasias da Glândula Tireoide/enzimologia , Adulto , Carcinoma Medular/química , Carcinoma Papilar/química , Carcinoma Papilar/genética , Ativação Enzimática , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização In Situ , Masculino , México , Pessoa de Meia-Idade , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-ret , Receptores Proteína Tirosina Quinases/análise , Receptores Proteína Tirosina Quinases/genética , Neoplasias da Glândula Tireoide/química , Neoplasias da Glândula Tireoide/genética
7.
J Hazard Mater ; 263 Pt 1: 67-72, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24184126

RESUMO

MgAl and MgAlTi mixed oxides were obtained from the thermal treatment of LDH materials synthesized by the sol-gel method; these materials were characterized by N2 physisorption, XRD, UV-vis, XPS, EDS-SEM and TEM techniques. According to the results, Ti was incorporated in the LDH layer when content in the material was low. The MgAl and MgAlTi mixed oxides were evaluated in the photo-degradation of 2,4-dichlorophenol (2,4-DCP) in the presence of UV light. A superior efficiency in the photo-degradation of 2,4-DCP, in comparison with the Degussa P-25 TiO2 reference catalyst was observed, reaching a total decomposition of the 2,4-DCP molecule in less than 60 min. According to the results, Ti was incorporated in the LDH layer when the content in the material was low. The MgAl and MgAlTi mixed oxides were evaluated in the photo-degradation of 2,4-dichlorophenol (2,4-DCP) in the presence of UV light. A superior efficiency in the photo-degradation of 2,4-DCP with the MgAl and MgAlTi mixed oxides, in comparison with the Degussa P-25 TiO2 reference catalyst was observed, reaching a total decomposition of the 2,4-DCP molecule in less than 60 min.


Assuntos
Alumínio/efeitos da radiação , Clorofenóis/química , Manganês/efeitos da radiação , Óxidos/efeitos da radiação , Titânio/efeitos da radiação , Poluentes Químicos da Água/química , Alumínio/química , Catálise , Hidróxidos/química , Manganês/química , Óxidos/química , Fotólise , Titânio/química , Raios Ultravioleta
8.
Rev Med Panama ; 20(1-2): 9-19, 1995.
Artigo em Espanhol | MEDLINE | ID: mdl-7480907

RESUMO

The clinical records and follow up of two patients with jaundice in the third trimester of pregnancy and final diagnosis of acute fatty liver of pregnancy (AFLP) are reported. The purpose of this paper is to orient clinicians on the appropriate diagnostic approach in every woman with jaundice in the third trimester of pregnancy.


Assuntos
Fígado Gorduroso/diagnóstico , Complicações na Gravidez/diagnóstico , Doença Aguda , Adulto , Biópsia , Evolução Fatal , Fígado Gorduroso/patologia , Feminino , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/patologia , Humanos , Fígado/patologia , Gravidez , Complicações na Gravidez/patologia , Terceiro Trimestre da Gravidez
9.
Rev. méd. Panamá ; 20(1/2): 9-19, Jan.-May 1995.
Artigo em Espanhol | LILACS | ID: lil-409947

RESUMO

The clinical records and follow up of two patients with jaundice in the third trimester of pregnancy and final diagnosis of acute fatty liver of pregnancy (AFLP) are reported. The purpose of this paper is to orient clinicians on the appropriate diagnostic approach in every woman with jaundice in the third trimester of pregnancy


Assuntos
Humanos , Feminino , Gravidez , Adulto , Complicações na Gravidez/diagnóstico , Fígado Gorduroso/diagnóstico , Biópsia , Complicações na Gravidez/patologia , Doença Aguda , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/patologia , Evolução Fatal , Fígado Gorduroso/patologia , Fígado/patologia , Terceiro Trimestre da Gravidez
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA