RESUMO
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.
Assuntos
Doença das Coronárias/sangue , Lipoproteínas LDL/sangue , Ácidos Siálicos/sangue , Adulto , Idoso , Feminino , Humanos , Lipoproteínas LDL/análise , Masculino , Pessoa de Meia-Idade , Ácidos Siálicos/análiseRESUMO
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.
Assuntos
Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Adulto , Glicemia/análise , Jejum , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
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.
Assuntos
Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/sangue , Lipoproteínas LDL/sangue , Apolipoproteínas B/sangue , Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangueRESUMO
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.
Assuntos
Hemoglobina J/genética , Talassemia beta/genética , Criança , Feminino , Humanos , LinhagemRESUMO
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.
Assuntos
Transtornos Imunoproliferativos/complicações , Paraproteinemias/complicações , Idoso , Humanos , Masculino , Mieloma Múltiplo/complicações , Fatores de Tempo , Macroglobulinemia de Waldenstrom/complicaçõesRESUMO
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.
Assuntos
Poluentes Atmosféricos/análise , Poeira/análise , Metais Pesados/análise , Calibragem , Monitoramento Ambiental/métodos , Filtração/instrumentação , Lasers , Limite de Detecção , Metalurgia , Análise Espectral/métodosRESUMO
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.
Assuntos
Creatina Quinase/química , Cromatografia de Afinidade , Creatina Quinase/sangue , Creatina Quinase/imunologia , Eletroforese em Gel de Ágar , Humanos , Imunoglobulina G/química , Técnicas Imunológicas , Técnicas In Vitro , IsoenzimasRESUMO
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.
Assuntos
Apolipoproteínas/sangue , Sangue Fetal/metabolismo , Lipídeos/sangue , Lipoproteínas/sangue , Adolescente , Adulto , Feminino , Idade Gestacional , Humanos , Recém-Nascido/sangue , Gravidez , Valores de ReferênciaRESUMO
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.