Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Talanta ; 127: 75-81, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24913859

RESUMEN

Heavy metals have long been known to be detrimental to human health and the environment. Their emission is mainly considered to occur via the atmospheric route. Most of airborne heavy metals are of anthropogenic origin and produced through combustion processes at industrial sites such as incinerators and foundries. Current regulations impose threshold limits on heavy metal emissions. The reference method currently implemented for quantitative measurements at exhaust stacks consists of on-site sampling of heavy metals on filters for the particulate phase (the most prominent and only fraction considered in this study) prior to subsequent laboratory analysis. Results are therefore known only a few days after sampling. Stiffer regulations require the development of adapted tools allowing automatic, on-site or even in-situ measurements with temporal resolutions. The Laser-Induced Breakdown Spectroscopy (LIBS) technique was deemed as a potential candidate to meet these requirements. On site experiments were run by melting copper bars and monitoring emission of this element in an exhaust duct at a pilot-scale furnace in a French research center dedicated to metal casting. Two approaches designated as indirect and direct analysis were broached in these experiments. The former corresponds to filter enrichment prior to subsequent LIBS interrogation whereas the latter entails laser focusing right through the aerosol for detection. On-site calibration curves were built and compared with those obtained at laboratory scale in order to investigate possible matrix and analyte effects. Eventually, the obtained results in terms of detection limits and quantitative temporal monitoring of copper emission clearly emphasize the potentialities of the direct LIBS measurements.


Asunto(s)
Contaminantes Atmosféricos/análisis , Polvo/análisis , Metales Pesados/análisis , Calibración , Monitoreo del Ambiente/métodos , Filtración/instrumentación , Rayos Láser , Límite de Detección , Metalurgia , Análisis Espectral/métodos
3.
Rev Med Interne ; 18(6): 470-3, 1997.
Artículo en Francés | MEDLINE | ID: mdl-9247046

RESUMEN

Three distinct monoclonal gammopathies were identified in the serum of a 79 year-old man. In 1972 he presented with Waldenström's macroglobulinemia IgM Kappa. Twenty years later multiple myeloma was diagnoses. Serum protein electrophoresis performed at this time showed three monoclonal bands. Immunofixation identified these bands as monoclonal IgM kappa, IgG kappa and IgA kappa. Twenty-six cases of triclonal gammopathies were previously reported. Sixteen cases were associated with malignant immuno-proliferative diseases (non-hodgkin lymphoma, Waldenström's macroglobulinemia, multiple myeloma); five cases with non-hematologic diseases; three cases were of undetermined significance. The origin of three distinct monoclonal proteins may derive from three unrelated clones or alternatively from a single clone in which an isotype switch has occurred.


Asunto(s)
Trastornos Inmunoproliferativos/complicaciones , Paraproteinemias/complicaciones , Anciano , Humanos , Masculino , Mieloma Múltiple/complicaciones , Factores de Tiempo , Macroglobulinemia de Waldenström/complicaciones
4.
Ann Biol Clin (Paris) ; 54(8-9): 321-3, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9092311

RESUMEN

The authors report a case, not described so far in literature, of an association of HbJ-Broussais [alpha (90 (PG2) lys-->asn beta 2] with beta + thalassemia in a young girl born of Italian father and Breton mother. This association is clinically silent. Biochemistry revealed, besides HbA, the presence of HbJ-Broussais in the proportion of 19.4% and HbA2 value of 3.9%. These percentages, slightly lower than expected, are explained. A familial study is presented.


Asunto(s)
Hemoglobina J/genética , Talasemia beta/genética , Niño , Femenino , Humanos , Linaje
6.
Prenat Diagn ; 15(3): 225-8, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7784380

RESUMEN

Blood collected from 62 fetuses aged 20-38 weeks of gestation was studied. The values of ten lipid parameters were determined: cholesterol (TC), triglycerides (TGs), apolipoprotein A1 (apo A1), apolipoprotein B (apo B), apolipoprotein E (apo E), total apolipoprotein CIII (apo CIII), apolipoprotein CIII present in particles containing apo B (apo CIII LpB) or not (apo CIII Lp non-B), lipoparticles A1 (LpA1), and lipoprotein a (Lp(a)). The results show that, except for apo E, all the studied parameters were present in lower concentrations than in adults and newborns, and that Lp(a) is not detectable at that stage in life.


Asunto(s)
Apolipoproteínas/sangre , Sangre Fetal/metabolismo , Lípidos/sangre , Lipoproteínas/sangre , Adolescente , Adulto , Femenino , Edad Gestacional , Humanos , Recién Nacido/sangre , Embarazo , Valores de Referencia
8.
Diabete Metab ; 20(3): 258-64, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8001713

RESUMEN

Lipid peroxidation was assessed by measuring the concentrations of thiobarbituric acid-reactive substances in plasma from 204 Type 2 diabetic patients, relative to 107 controls. The concentrations obtained in diabetic patients (3.08 +/- 0.37 mumol/l) were significantly higher than in controls (2.80 +/- 0.34 mumol/l) (p < 0.0001). Values were also significantly increased in patients with macroangiopathy and/or microangiopathy (3.17 +/- 0.41 mumol/l), relative to patients void of vascular complications (2.92 +/- 0.34 mumol/l) (p < 0.001). Elevated concentrations were independent of the type of vascular complication and their possible associations. In patients without vascular affection, thiobarbituric acid-reactive substances were in significantly higher concentrations in hypertensive (3.07 +/- 0.36 mumol/l) than in normotensive (2.87 +/- 0.29 mumol/l) (p < 0.01) patients. There was a correlation between these values and those of total cholesterol (r = 0.46, p < 0.0001) and triglyceride (r = 0.45, p < 0.0001). Statistical analysis by multivariate logistical regression revealed that among the independent factors (TBARS, APO A1, hypertension, age), thiobarbituric acid-reactive substances constituted the parameter most strongly linked to the existence of vascular complications. This study has evidenced a lipid peroxidation disorder in non insulin- dependent diabetes mellitus, more marked in patients with vascular affection. Thiobarbituric acid-reactive substances appear to be an independent marker of vascular complications in Type 2 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Angiopatías Diabéticas/sangre , Hipertensión/sangre , Lípidos/sangre , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Adulto , Anciano , Apolipoproteína A-I/sangre , Apolipoproteínas B/sangre , Biomarcadores/sangre , Glucemia/metabolismo , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Hemoglobina Glucada/análisis , Humanos , Hipertensión/complicaciones , Peroxidación de Lípido , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valores de Referencia , Análisis de Regresión , Triglicéridos/sangre
9.
Ann Biol Clin (Paris) ; 52(10): 695-9, 1994.
Artículo en Francés | MEDLINE | ID: mdl-7747876

RESUMEN

Since oxidized LDL may play a role in the genesis of atheroma, which is the primary complication of non-insulin-dependent diabetes mellitus (NIDDM), we investigated whether the LDL of diabetic patients were more prone to oxidation than those of healthy controls. We therefore studied the susceptibility of LDL to oxidation by phenylhydrazine (LDL-PO) in NIDDM patients with or without macroangiopathy, and in controls. Results showed that the LDL of patients with macroangiopathy (n = 50) were more susceptible to oxidation than those of both NIDDM patients without vascular complications (n = 50) and controls (n = 50). In diabetic patients, there was a positive correlation between LDL-PO and the following parameters: total cholesterol, triglycerides, LDL cholesterol, apolipoprotein B. In contrast, there was no correlation between LDL-PO and the parameters of glycemic control (fasting glucose, HbAlc). After analyzing the composition of LDL, it appeared that LDL-PO values in diabetic patients were positively correlated with those of all LDL constituents. The increase in LDL-PO observed in the group of NIDDM patients with macroangiopathy could be a consequence of an increase in the LDL triglyceride content in these patients.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Angiopatías Diabéticas/sangre , Lipoproteínas LDL/sangre , Apolipoproteínas B/sangre , Colesterol/sangre , LDL-Colesterol/sangre , Femenino , Humanos , Peroxidación de Lípido , Masculino , Persona de Mediana Edad , Triglicéridos/sangre
10.
Clin Chim Acta ; 221(1-2): 127-33, 1993 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-8149630

RESUMEN

Low density lipoproteins (LDL) are considered to be the most atherogenic of lipoproteins. These LDL can be modified and oxidative modifications are now well known. In addition, other atherogenic modifications of LDL exist, such as desialylation. In the present study sialic acid content was determined in LDL preparations obtained from patients with coronary artery disease (CAD+) and compared with that of healthy subjects and patients without coronary heart disease (CAD-). The sialic acid concentration was found to be statistically lower (P < 0.05) in the LDL of CAD+ patients (11.6 +/- 2.7 micrograms/mg of protein) than in the LDL of controls (16.5 +/- 5.6 micrograms/mg of protein) or in the LDL of CAD- patients (15.3 +/- 3.8 micrograms/mg of protein). In subgroups of CAD+ patients divided according to the severity of the disease, no statistically significant difference was observed in LDL sialic acid content. This work confirms the presence of desialylated LDL in the sera of patients with atheroma.


Asunto(s)
Enfermedad Coronaria/sangre , Lipoproteínas LDL/sangre , Ácidos Siálicos/sangre , Adulto , Anciano , Femenino , Humanos , Lipoproteínas LDL/análisis , Masculino , Persona de Mediana Edad , Ácidos Siálicos/análisis
13.
Clin Chim Acta ; 214(2): 227-34, 1993 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-8472388

RESUMEN

Malondialdehyde, a marker of lipid peroxidation, was measured as thiobarbituric acid reactive substances (TBARS) in 117 diabetic patients and 53 controls. Patients were divided into groups and subgroups according to the type of diabetes (type 1 and type 2) and the existence or not of vascular complication (macro- or micro-angiopathy). Results showed that TBARS concentrations were significantly higher in type 1 (P < 0.0001) and type 2 (P < 0.001) diabetic patients than in the control group. The plasma TBARS concentrations in type 1 and type 2 diabetic patients did not differ significantly. Among the patients with vascular disease, type 2 diabetic patients with macroangiopathy had significantly higher TBARS concentrations than patients with no vascular complication (P < 0.05). Whichever the type of diabetes, there was no correlation between TBARS concentrations and glycaemic control: glycosylated haemoglobin, fasting blood glucose. This study confirmed the existence of lipid peroxidation disorders in diabetic patients.


Asunto(s)
Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 2/sangre , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Adulto , Glucemia/análisis , Ayuno , Femenino , Hemoglobina Glucada/análisis , Humanos , Masculino , Persona de Mediana Edad
14.
Pathol Biol (Paris) ; 39(8): 785-8, 1991 Oct.
Artículo en Francés | MEDLINE | ID: mdl-1762837

RESUMEN

A macrocreatine-kinase type 1 was identified by CK isoenzyme electrophoresis of a serum sample from a patient. Constituents of this enzyme complex were studied. The isoenzyme present in the macrocreatine-kinase was identified using immunoprecipitation with antibodies against the M subunit. Affinity chromatography then determined the type of the immunoglobulin bound to the CK isoenzyme. A protocol for studying macrocreatine-kinase type 1 compounds is proposed.


Asunto(s)
Creatina Quinasa/química , Cromatografía de Afinidad , Creatina Quinasa/sangre , Creatina Quinasa/inmunología , Electroforesis en Gel de Agar , Humanos , Inmunoglobulina G/química , Técnicas Inmunológicas , Técnicas In Vitro , Isoenzimas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA