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1.
J Hazard Mater ; 416: 126199, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-34492963

RESUMEN

This study reports the photocatalytic degradation of diclofenac by hybrid materials prepared by combination of graphitic carbon nitride (g-C3N4) and titanium-metal organic framework (NH2-MIL-125), in different mass proportions (MOF:C3N4 of 25:75, 50:50 and 75:25). The hybrid materials were fully characterized, and their properties compared to those of the individual components, whose presence was confirmed by XRD. The porous structure was the result of the highly microporous character of the MOF and the non-porous one of g-C3N4. The band gap values were very close to that of MOF component. Photoluminescence measurements suggested an increase on the recombination rate associated to the presence of g-C3N4. Photodegradation tests of diclofenac (10 mg·L-1) were performed under UV LED irradiation at 384 nm. The hybrid materials showed higher photocatalytic activity than the individual components, suggesting the occurrence of some synergistic effect. The photocatalyst with a MOF:g-C3N4 ratio of 50:50 yielded the highest conversion rate, allowing complete disappearance of diclofenac in 2 h. Experiments with scavengers showed that superoxide radicals and holes played a major role in the photocatalytic process photodegradation, being that of hydroxyl radicals less significant. From the identification of by-products species, a degradation pathway was proposed for the degradation of diclofenac under the experimental operating conditions.


Asunto(s)
Diclofenaco , Agua , Catálisis , Fotólisis
2.
Transplant Proc ; 36(4): 827-9, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15194285

RESUMEN

Allelic differences in gene promoter or codifying regions have been described to affect regulation of gene expression, consequently increasing or decreasing cytokine production and signal transduction responses to a given stimulus. This observation has been reported for interleukin (IL)-10 (-1082 A/G; -819/-592 CT/CA), transforming growth factor (TGF)-beta (codon 10 C/T, codon 25 G/C), tumor necrosis factor (TNF)-alpha (-308 G/A), TNF-beta (+252 A/G), interferon (IFN)-gamma (+874 T/A), IL-6 (-174 G/C), and IL-4R alpha (+1902 G/A). To evaluate the influence of these cytokine genotypes on the development of acute or chronic rejection, we correlated the genotypes of both kidney graft recipients and cadaver donors with the clinical outcome. Kidney recipients had 5 years follow-up, at least 2 HLA-DRB compatibilities, and a maximum of 25% anti-HLA pretransplantation sensitization. The clinical outcomes were grouped as follows: stable functioning graft (NR, n = 35); acute rejection episodes (AR, n = 31); and chronic rejection (CR, n = 31). The cytokine genotype polymorphisms were defined using PCR-SSP typing. A statistical analysis showed a significant prevalence of recipient IL-10 -819/-592 genotype among CR individuals; whereas among donors, the TGF-beta codon 10 CT genotype was significantly associated with the AR cohort and the IL-6 -174 CC genotype with CR. Other albeit not significant observations included a strong predisposition of recipient TGF-beta codon 10 CT genotype with CR, and TNF-beta 252 AA with AR. A low frequency of TNF-alpha -308 AA genotype also was observed among recipients and donors who showed poor allograft outcomes.


Asunto(s)
Citocinas/genética , Neoplasias Renales/inmunología , Genotipo , Rechazo de Injerto/inmunología , Humanos , Interleucina-10/genética , Interleucina-6/genética , Factor de Crecimiento Transformador beta/genética , Trasplante Homólogo , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/genética
3.
J Int Med Res ; 27(3): 148-57, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10505305

RESUMEN

The efficacy and safety of lamotrigine as add-on therapy in treatment-resistant epilepsy were evaluated in an open prospective study carried out at five centres in Portugal and involving 61 patients. Daily seizure diaries were kept by patients, and used by the investigators to give a rating of response to therapy. Assessments were recorded after 1, 2, 3, 6, 9, 12, 18 and 24 months. Overall, seizure control was improved in 57% of patients, remained unchanged in 34% and deteriorated in 9%. There were some indications that efficacy was greatest in patients with generalized seizures and in those taking concomitant valproate. Efficacy was maintained throughout the 2-year study. It was possible to reduce the dose of concomitant antiepileptic drug in 56% of patients, and seven patients no longer needed a concomitant antiepileptic drug. Although 75% of patients reported an adverse experience, most of these were mild or moderate in intensity, did not require treatment and were not judged to be serious. A total of 13 patients withdrew from the study (four due to adverse events, four due to lack of efficacy and five for other reasons).


Asunto(s)
Anticonvulsivantes/administración & dosificación , Epilepsia/tratamiento farmacológico , Triazinas/administración & dosificación , Administración Oral , Adolescente , Adulto , Anticonvulsivantes/efectos adversos , Niño , Resistencia a Medicamentos , Femenino , Humanos , Lamotrigina , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Convulsiones , Resultado del Tratamiento , Triazinas/efectos adversos
4.
Mol Gen Genet ; 239(1-2): 235-40, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8510650

RESUMEN

In Bradyrhizobium japonicum, Tn5 insertions in a particular chromosomal DNA fragment result in a Hup- phenotype in free-living conditions without affecting hydrogenase (Hup) activity in the symbiotic state. By determination of the nucleotide sequence of this region, we were able to identify the nature of the inactivated genes. The fragment is located 9 kb downstream of the hydrogenase structural genes and contains one incomplete and three complete open reading frames. They are designated hypD', hypE, hoxX and hoxA respectively, since the deduced amino acid sequences display very strong homology with genes involved in the regulation of hydrogenase activity in Escherichia coli, Rhodobacter capsulatus, Azotobacter vinelandii (hypD' and hypE) and Alcaligenes eutrophus (hoxX and hoxA). This is the first report on transcriptional activators of the hup genes in B. japonicum. Implications of these findings with respect to regulation of hydrogenase synthesis by hydrogen, oxygen and nickel in free-living B. japonicum are discussed.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Hidrogenasas/genética , Rhizobiaceae/genética , Transcripción Genética , Secuencia de Aminoácidos , Secuencia de Bases , ADN Bacteriano , Hidrogenasas/metabolismo , Datos de Secuencia Molecular , Mapeo Restrictivo , Rhizobiaceae/enzimología , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico
7.
J Gen Virol ; 73 ( Pt 5): 1049-56, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1588315

RESUMEN

The genomic region of the Anticarsia gemmatalis multiple nucleocapsid nuclear polyhedrosis virus (AgMNPV) strain 2D encoding the polyhedrin gene was cloned and mapped, and a 2085 bp SphI-PstI fragment containing the gene was sequenced. The polyhedrin polypeptide of the parental isolate AgMNPV was manually sequenced, and the amino acid sequence obtained agreed with that deduced from the DNA coding region sequence. AgMNPV and Orgyia pseudotsugata MNPV (OpMNPV) are similar in terms of promoter structure and polyhedrin primary sequence, and the polyhedrin gene of both viruses is transcribed in the anti-clockwise direction in relation to their physical maps. The region upstream from the polyhedrin gene of AgMNPV, OpMNPV, Bombyx mori NPV and Autographa californica MNPV (AcMNPV) was compared and this showed that the open reading frame (ORF) common to all four viruses (ORF 5) has sequence homology with the AcMNPV 25K gene. The sequences between ORF 5 and the polyhedrin gene were found to be variable among the polyhedrin gene loci compared. Additionally, conserved elements in the promoters of the very late genes encoding polyhedrin and granulin, and those encoding two p10 proteins were found to share sequence homology and positional similarity with consensus regions in the conserved boxes A and C, responsible for binding transcription factors to eukaryotic 5S ribosomal RNA genes, and to box C of tRNA genes.


Asunto(s)
Baculoviridae/genética , Genes Virales/genética , Insectos/microbiología , Proteínas Virales/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Mapeo Cromosómico , Clonación Molecular , Secuencia de Consenso , Datos de Secuencia Molecular , Proteínas de la Matriz de Cuerpos de Oclusión , Regiones Promotoras Genéticas/genética , Homología de Secuencia de Ácido Nucleico , Proteínas Estructurales Virales
8.
Acta Med Port ; 4(5): 231-5, 1991.
Artículo en Portugués | MEDLINE | ID: mdl-1664642

RESUMEN

150 patients, subjected to kidney graft transplantation between January 1988 and December 1989, were studied. Mean +/- 95% CL age was 37.5 +/- 2.03 (range 12-69) years. IgG and IgM antibodies levels (ELISA) cytomegalovirus (CMV) were investigated in the donor before organ harvesting and in the kidney recipients on 1st and 21th days and then on the 3rd, 6th and 9th months after transplantation. Patients lacking either donor or 1st day studies were excluded. 133 donor (D) receptor (R) pairs were classified as group 1) D+/R+, 2) D+/R-, 3) D-/R+ e 4) D-/R-. Prevalence, severity of CMV disease and date of diagnosis were studied. Mean time +/- 95% CI of diagnosis after transplantation was 78.4 +/- 15.1 days. Seronegative receptors had a statistically significant higher prevalence of the disease as to seropositive receptors, but not a higher incidence of disease severity. One out of five patients had a serious form of disease. Hiperimmune globulin was used in 15 patients (all serious forms and 3 moderate forms of of disease). No patient died as a result of CMV infection.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Citomegalovirus/sangre , Citomegalovirus/inmunología , Trasplante de Riñón , Adolescente , Adulto , Anciano , Niño , Infecciones por Citomegalovirus/epidemiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Donantes de Tejidos
9.
Eur J Biochem ; 159(3): 597-604, 1986 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-3758080

RESUMEN

Storage proteins of the albumin solubility fraction from seeds of Bertholletia excelsa H.B.K. were separated by reversed-phase high-performance liquid chromatography and their primary structures were determined by gas-phase sequencing on intact polypeptides and on the overlapping tryptic and thermolysin peptides. The 2S storage proteins consist of two subunits linked by disulphide bridges. The large subunit (8.5 kDa) is expressed in at least six different isoforms while the small subunit (3.6 kDa) consists of only one form. These proteins are extremely rich in glutamine, glutamic acid, arginine and the sulphur-containing amino acids cysteine and methionine. One of the variants even contains a sequence of six methionine residues in a row. Comparison with known sequences of 2S proteins of other dicotyledonous plants shows limited but distinct sequence homology. In particular, the positions of the cysteine residues relative to each other appear to be completely conserved, suggesting that tertiary structure constraints imposed by disulphide bridges dominate sequence conservation. It has been proposed that the two subunits of a related protein (the Brassica napus storage protein) is cleaved from a precursor polypeptide [Crouch, M. L., Tenbarge, K. M., Simon, A. E. & Ferl, R. (1983) J. Mol. Appl. Genet. 2,273-283]. The amino acid sequence homology of the Brazil nut protein with the former suggests that a similar protein processing event could occur.


Asunto(s)
Nueces/análisis , Proteínas de Plantas , Secuencia de Aminoácidos , Fragmentos de Péptidos , Proteínas de Plantas/aislamiento & purificación
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