Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
Anal Bioanal Chem ; 397(7): 2763-76, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20428853

RESUMO

The presence of a wide variety of organic pollutants with different physicochemical characteristics has been investigated in wastewater samples from a municipal solid-waste-treatment plant in Castellón, Spain. An advanced analytical strategy was applied--combined used of two powerful and complementary techniques, GC and LC, both hyphenated with tandem mass spectrometry with triple-quadrupole analyzers. The GC-MS-MS method was based on sample extraction using C(18) SPE cartridges and enabled the determination of approximately 60 compounds from different chemical families, for example PAHs, octyl/nonylphenols, PCBs, organochlorine compounds, insecticides, herbicides, and PBDEs. Most of the compounds selected are included as priority contaminants in the European Union (EU) Water Directive. The UHPLC-MS-MS method, which provided high chromatographic resolution and sensitivity and short analysis time, used sample extraction with Oasis HLB SPE cartridges and enabled the determination of 37 (more polar) pesticides. The methodology developed was applied to the analysis of 41 water samples (20 untreated raw leachates and 21 treated samples) collected between March 2007 and February 2009. Amounts of the contaminants investigated rarely exceeded 0.5 microg L(-1) in the treated (reverse osmosis) water samples analyzed. As expected, in untreated leachates the number of compounds detected and the concentrations found were notably higher than in treated waters. The most commonly detected pollutants were herbicides (simazine, terbuthylazine, terbutryn, terbumeton, terbacil, and diuron), fungicides (thiabendazole and carbendazim), and 4-t-octylphenol. The results obtained proved that use of reverse osmosis for water treatment was efficient and notably reduced the amounts of organic contaminants found in raw leachate samples. In order to investigate the presence of other non-target contaminants, water samples were also analyzed by using GC-TOF MS and LC-QTOF MS. Several organic pollutants that did not form a part of the previous list of target contaminants were identified in the samples, because of the high sensitivity of TOF MS in full-spectrum acquisition mode and the valuable accurate-mass information provided by these instruments. The insecticide diazinon, the fungicide diphenylamide, the UV filter benzophenone, N-butylbenzenesulfonamide (N-BBSA), the insect repellent diethyltoluamide, caffeine, and the pharmaceuticals erythromycin, benzenesulfonanilide, ibuprofen, atenolol, and paracetamol were some of the compounds identified in the water samples analyzed.


Assuntos
Cromatografia Gasosa/métodos , Cromatografia Líquida/métodos , Praguicidas/análise , Esgotos/análise , Poluentes Químicos da Água/análise , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos
3.
Brain Res ; 902(1): 1-10, 2001 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-11376589

RESUMO

We investigated whether the effect of phorbol-12-myristate-13-acetate (PMA) was altered by a kinase inhibitor and by down-regulation of protein kinase C (PKC) in order to determine if glycine receptors in mouse spinal neurons, unlike those in hippocampal and trigeminal neurons, can be inhibited by PKC. To examine the above, electrophysiological and immunofluorescence studies were carried out in mouse spinal neurons kept in culture for up to 3 weeks. The inhibition of the glycine activated current by PMA (1 microM) increased from 12+/-3% during week 1 to 27+/-6% during week 3. The effect of PMA was completely blocked by the PKC selective inhibitor RO 31-8220 (1 microM). After culturing the cells with 1 microM PMA for 24 h, the inhibitory effect of acute application of PMA disappeared altogether, suggesting that the effect of PMA was via PKC. Immunofluorescence studies showed that a short stimulation with PMA translocated the enzyme to the periphery whereas longer term stimulation (24 h) down regulated the PKC signal. These results indicate that activation of PKC by PMA inhibits the glycine receptor in cultured spinal neurons and that its sensitivity changes during neuronal development.


Assuntos
Canais de Cloreto/efeitos dos fármacos , Cloretos/metabolismo , Glicina/farmacologia , Indóis/farmacologia , Transporte de Íons/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Proteína Quinase C/metabolismo , Receptores de Glicina/efeitos dos fármacos , Medula Espinal/citologia , Acetato de Tetradecanoilforbol/farmacologia , Animais , Células Cultivadas , Canais de Cloreto/metabolismo , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Transporte de Íons/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/antagonistas & inibidores , Neurônios/metabolismo , Técnicas de Patch-Clamp , Proteína Quinase C/antagonistas & inibidores , Receptores de Glicina/metabolismo , Transdução de Sinais/efeitos dos fármacos
4.
J Pharmacol Exp Ther ; 295(1): 423-9, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10992010

RESUMO

Five-day-old cultures of mouse glycinergic spinal interneurons were chronically treated with 100 mM ethanol and the glycine and gamma-aminobutyric acid (GABA)(A) receptors were assayed using whole-cell recordings and fluorescence-imaging techniques. Control neurons displayed a glycine(50) of 19 +/- 0.6 microM and a Hill coefficient of 3.1 +/- 0.3. Chronic ethanol treatment did not significantly change these parameters. The maximal responses were 310 +/- 80 pA/pF in control and 440 +/- 19 pA/pF in treated cells, and the fluorescence intensity associated to a monoclonal glycine receptor antibody was unchanged. Strychnine inhibited the glycine current with smaller potency (29%) in treated neurons, thus the IC(50) increased from 14 +/- 2 nM in control to 18 +/- 6 nM in treated neurons. Zn(2+) (10 microM) potentiated the glycine current by 43 +/- 33% in control, but only by 18 +/- 13% in treated neurons. Interestingly, no change on the inhibition produced by a high concentration of Zn(2+) was found in treated neurons. The inhibitory effect of picrotoxin on the glycine receptor, associated to a homomeric receptor, was eliminated with chronic ethanol, suggesting a faster switch to beta-subunit-containing receptors. Unlike glycine receptors, the sensitivity of GABA(A) receptors to GABA, pentobarbital, diazepam, and Zn(2+), as well as the fluorescence intensity associated to a high-affinity benzodiazepine analog was unchanged by chronic ethanol. In conclusion, we found that glycine receptors in spinal interneurons were altered by chronic ethanol treatment and this may reflect the expression of different subunits in control and treated neurons. GABA(A) receptors were resistant to the treatment.


Assuntos
Etanol/toxicidade , Interneurônios/efeitos dos fármacos , Receptores de GABA-A/efeitos dos fármacos , Receptores de Glicina/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Animais , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Picrotoxina/farmacologia , Estricnina/farmacologia , Zinco/farmacologia
5.
Br J Haematol ; 110(1): 98-103, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10930984

RESUMO

Hepatitis C virus (HCV) has been proposed as a possible causative agent of chronic thrombocytopenia. We investigated HCV infection in a series of 51 unselected Spanish patients with chronic acquired thrombocytopenia. Anti-HCV and HCV viraemia were detected in 13/51 (22.5%) of cases; this prevalence was particularly significant when compared with HCV seropositivity in age-matched controls (0.4%). Anti-HCV-positive patients, four men and nine women with a median age of 59.3 years (range 36-72), had a mean platelet count of 55.8 x 109/l (range 12-96). Only one of our HCV-positive thrombocytopenic patients had hypersplenism. Platelet-associated IgG (PAIgG) was negative, as measured by immunofluorescent flow cytometric analysis in 11/13 HCV-positive thrombocytopenic patients. Thus, thrombocytopenia in our HCV-positive patients appeared to be non-autoimmune mediated. In six patients, a trial of recombinant alpha2b-interferon (IFN-alpha) given at a dose of 3 MU three times per week for 6-24 months gave a durable (> 1 year) and significant increase in platelet count in all six patients. The maximum increase occurred after 6 months of IFN-alpha therapy. In conclusion, the ability of IFN-alpha to increase platelet counts in HCV-positive thrombocytopenic patients supports mechanisms involving a direct role for HCV inhibiting platelet production.


Assuntos
Hepatite C/complicações , Interferon-alfa/uso terapêutico , Trombocitopenia/virologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Doença Crônica , Danazol/uso terapêutico , Antagonistas de Estrogênios/uso terapêutico , Feminino , Hepatite C/sangue , Hepatite C/tratamento farmacológico , Humanos , Imunoglobulinas Intravenosas/administração & dosagem , Imunossupressores/uso terapêutico , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Prednisolona/uso terapêutico , Prevalência , Proteínas Recombinantes , Esplenectomia , Trombocitopenia/sangue , Trombocitopenia/tratamento farmacológico
6.
Rev Neurol ; 27(159): 836-7, 1998 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-9859163

RESUMO

Multiple sclerosis is a disorder with different forms of clinical presentation. The Brown-Séquard syndrome has occasionally been described in association with multiple sclerosis. We present the case of a patient whose initial clinical presentation of multiple sclerosis was the Brown-Séquard syndrome.


Assuntos
Síndrome de Brown-Séquard/etiologia , Esclerose Múltipla/complicações , Adulto , Encéfalo/patologia , Síndrome de Brown-Séquard/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/patologia , Medula Espinal/patologia
7.
J Infect ; 37(1): 79-81, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9733390

RESUMO

We report an acute Q fever case, a febrile syndrome, in the 14th week of pregnancy. Placental infection was documented by Coxiella burnetii culture. Newborn infection was ruled out on the basis of the absence of serological evidence after 2 years and on clinical normality. Serological diagnosis is reviewed here, as maternal serology was suggestive of chronic Q fever. The clinical progress, following extended observation, was consistent with acute infection. A QpDV plasmid, already described as being common to acute and chronic European cases, was detected.


Assuntos
Coxiella burnetii/isolamento & purificação , Complicações Infecciosas na Gravidez/microbiologia , Febre Q/microbiologia , Adulto , Anticorpos Antibacterianos/sangue , Pré-Escolar , DNA Bacteriano/análise , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Placenta/microbiologia , Plasmídeos , Polimorfismo de Fragmento de Restrição , Gravidez , Segundo Trimestre da Gravidez
8.
Cytometry ; 26(2): 125-30, 1996 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-8817088

RESUMO

We describe a 57-year-old woman who presented with a constitutional syndrome, glomerulonephritis, and lymphocytosis. The phenotypic study, using flow cytometry, showed an expansion of natural killer (NK) cells (CD2+, CD3-, CD16+, CD56+, and CD7+). We performed a functional study of peripheral blood mononuclear cells (PBMCs) and of purified CD16+ cells (NK cells) and CD3+ cells (normal T cells). The expanded NK cell population, CD16+, did not proliferate with phytohemagglutinin (PHA) or anti-CD3 but showed a dose-dependent proliferation with recombinant interleukin-2 (rIL-2) and also proliferated with phorbol dibutyrate. This population showed very strong NK and lymphokine-activated killer cell (LAK) activities. The patient's symptoms resolved spontaneously without treatment. Three years later, however, there is still abnormal renal function, and the expansion of NK cells persists, although with no indication of malignancy. We review the features of the different large granular lymphocyte proliferations and their seldom described relationship with renal disease.


Assuntos
Antígenos CD/imunologia , Glomerulonefrite/imunologia , Células Matadoras Ativadas por Linfocina/imunologia , Células Matadoras Naturais/imunologia , Linfocitose/imunologia , Biomarcadores , Complexo CD3/imunologia , Divisão Celular , Feminino , Glomerulonefrite/sangue , Glomerulonefrite/complicações , Humanos , Interleucina-2/farmacologia , Células Matadoras Naturais/citologia , Leucócitos Mononucleares/imunologia , Linfocitose/sangue , Linfocitose/complicações , Pessoa de Meia-Idade , Mitógenos/farmacologia , Fenótipo , Fito-Hemaglutininas/farmacologia
9.
Eur J Endocrinol ; 132(2): 175-80, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7858736

RESUMO

We studied the natural killer (NK) activity of peripheral blood mononuclear cells (PBMC) in patients with Graves' disease (GD). Peripheral blood mononuclear cells from 20 untreated hyperthyroid patients with GD showed a significantly reduced NK activity against 51 Cr-labeled K562 cells (33.9 +/- 15.9%), while in 32 euthyroid patients under antithyroid drug therapy. NK activity was similar to that of controls (46.9 +/- 17.3 and 49.9 +/- 20.2%, respectively). Furthermore, normalization of thyroid function with antithyroid drugs was associated with a significant increase and normalization of NK activity during the follow-up of nine GD patients (from 29.2 +/- 17.9 to 48.1 +/- 16.5%). This phenomenon could not be ascribed to a defective number of NK cells because the amounts of CD56+ and CD16+ cells in PBMC from both hyperthyroid and euthyroid GD patients were within normal ranges. Natural killer activity of PBMC from patients with toxic multinodular goiter was similar to that of normal controls (45 +/- 12.8 to 49.9 +/- 20%). No correlation was found between natural killer activity and serum levels of free thyroxine, TSH-inhibitory immunoglobulins, thyroidal antibodies to thryoglobulin and thyroidal microsomal antigen, dose or duration of antithyroid drug therapy. Natural killer activity from both controls and GD patients was enhanced in vitro by addition of recombinant interleukin 2 (IL-2), reaching control levels in hyperthyroid patients. These abnormalities were not associated with a defective IL-2 production by T cells, nor with a decreased IL-2R expression. We conclude that in untreated Graves' disease there is a decrease in NK cell activity in PBMC, probably dependent on the autoimmune process.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Citotoxicidade Imunológica/efeitos dos fármacos , Doença de Graves/imunologia , Células Matadoras Naturais/imunologia , Leucócitos Mononucleares/imunologia , Adulto , Contagem de Células , Feminino , Doença de Graves/sangue , Humanos , Interleucina-2/farmacologia , Masculino , Pessoa de Meia-Idade , Receptores de IgG/análise , Tiroxina/sangue
10.
Gut ; 36(2): 171-5, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7883211

RESUMO

The functional response and phenotypic characterisation of peripheral blood T cells were studied in 41 patients with autoimmune gastritis--nine patients with autoimmune gastritis alone, 11 with untreated pernicious anaemia, and 21 with resolved pernicious anaemia who were taking vitamin B-12. Phenotypic analysis showed no changes in the CD4/CD8 ratio in any group of patients. CD3+ cells were significantly decreased and CD16+ cells were significantly increased in patients with autoimmune gastritis alone. Phytohaemagglutinin induced T cell proliferation, with or without interleukin 2, was reduced in the three groups. T cell proliferation induced by phorbol myristate acetate was normal. Interleukin 2 production of phytohaemagglutinin-stimulated lymphocytes was normal in the three groups. Five patients with pernicious anaemia treated with vitamin B-12 were followed and persistent hypoproliferation of T cells in response to phytohaemagglutinin was observed. The follow up study of the phenotype of these patients showed a significant increase of the CD2+ CD3- lymphocyte population after six months' treatment. In conclusion, the three groups of autoimmune gastritis patients studied have a functional defect in T cells that is independent of B-12 treatment and of the presence of pernicious anaemia.


Assuntos
Doenças Autoimunes/sangue , Gastrite/imunologia , Linfócitos T/imunologia , Idoso , Anemia Perniciosa/complicações , Anemia Perniciosa/tratamento farmacológico , Complexo CD3/análise , Relação CD4-CD8 , Doença Crônica , Feminino , Gastrite/complicações , Humanos , Ativação Linfocitária , Masculino , Fenótipo , Estudos Prospectivos , Receptores de IgG/análise , Vitamina B 12/uso terapêutico
11.
Gut ; 35(7): 955-60, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8063224

RESUMO

There is increasing evidence that ulcerative colitis is associated with an abnormality of the immune system. Although the aetiology remains unknown, it has been suggested that the immune system of these patients is implicated in the pathogenesis of their disease. T cell function was investigated in ulcerative colitis patients and defective phytohaemagglutinin induced T cell mitogenesis was found. The DNA synthesis induced by stimulation with phorbol esters plus ionophore (ionomycin), however, was normal. These changes cannot be ascribed to either decreased interleukin 2 synthesis or to a defective interleukin 2 receptor expression after cellular activation. Moreover, this defective proliferative response of the T lymphocytes was observed even in the presence of saturated concentrations of exogenous interleukin 2. These results emphasise that the interleukin 2 dependent proliferation pathway is deficient in T lymphocytes from ulcerative colitis patients.


Assuntos
Colite Ulcerativa/imunologia , Interleucina-2/metabolismo , Linfócitos T/fisiologia , Adolescente , Adulto , Idoso , Divisão Celular/efeitos dos fármacos , Divisão Celular/imunologia , Membrana Celular/imunologia , Células Cultivadas , DNA/biossíntese , Feminino , Humanos , Ionomicina/farmacologia , Masculino , Pessoa de Meia-Idade , Fito-Hemaglutininas/farmacologia , Receptores de Interleucina-2/metabolismo , Estimulação Química , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
15.
Postgrad Med J ; 65(766): 570-4, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2602256

RESUMO

Two cases of meningeal invasion by non-myelomatous plasma cell dyscrasias--a plasma cell leukaemia and an extramedullary plasmacytoma--are described. Both were secretors of IgD paraprotein and both were diagnosed in life, characteristics which we have not found in any other published case of plasma cell leptomeningitis. Analysis of our patients and of another 25 cases suggests as predisposing factors of meningeal invasion the male sex, presentation in the form of plasma cell leukaemia, presence of the IgD paraprotein and tumoral involvement of pleura, lung, pericardium and testicles. Aggressive treatment of this neurological complication controlled the meningeal disorder in some cases. However, the majority died of disseminated disease in spite of systemic chemotherapy. Until an effective treatment can be found, able to maintain remission or cure the systemic disease, prophylaxis of the central nervous system in plasma cell dyscrasias does not appear to be advisable.


Assuntos
Imunoglobulina D/metabolismo , Leucemia Plasmocitária/imunologia , Neoplasias Meníngeas/imunologia , Paraproteinemias/imunologia , Plasmocitoma/imunologia , Adulto , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico por imagem , Pessoa de Meia-Idade , Invasividade Neoplásica , Paraproteinemias/diagnóstico por imagem , Plasmocitoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA