Administration of the plasticizer di (2-ethylhexyl) phthalate alters glycoconjugate profile.

This study was undertaken to evaluate the level of glycoproteins and sialic acid in rats fed di (2-ethylhexyl)-phthalate (DEHP) in the diet for 24 weeks. Protein-bound hexose, hexosamine and sialic acid were increased in plasma and liver of rats treated with DEHP, whereas the erythrocyte membrane showed a reduction following DEHP administration. Evaluation of glycoproteins is a useful indicator of the carcinogenic process. It is suggested that profound alterations in membrane components observed in the present study may be related to the carcinogenic potential of DEHP.

Glycation of blood proteins during pregnancy and lactation in the rat

Non-enzymatic glycation of blood proteins is a time and concentration dependent process and has been used clinically to monitor carbohydrate metabolism during human pregnancy. Since gestation in rats is of much shorter duration than in humans (3 weeks vs 9 mos) the question was raised whether similar differences in glycated proteins could be observed. Therefore, levels of glucose, glycated hemoglobin and fructosamine were measured during normal pregnancy and lactation in rats. Glucose levels during late pregnancy were significantly lower than in non pregnant and early pregnant rats. During lactation glucose levels return to normal. Glycated hemoglobin paralleled glucose decrease during late pregnancy and increased during lactation. Fructosamine followed a similar pattern. Therefore glycated hemoglobin and fructosamine appear to be reliable indicators of glucose status during gestation and lactation similar to humans and may have value as predictors of gestational diabetes mellitus once a suitable rat model is developed

Influence of serum albumin & total protein on fructosamine measurement.

To assess the effect of serum albumin and total protein on the fructosamine level 57 hypoalbuminaemic patients (serum albumin less than 30 g/1), of whom 44 were nondiabetics and 13 were diabetics, were studied. Fructosamine levels of hypoalbuminaemic diabetics was increased only marginally in comparison to healthy controls (P greater than 0.05) whereas in 122 other normalbuminaemic diabetics, the level was found to be significantly higher (P less than 0.001). In control subjects, the correlation between fructosamine and serum albumin (r = 0.69, P less than 0.001) was better than that of total protein (r = 0.42, P less than 0.01) whereas in hypoalbuminaemic patients the pattern was reversed (r = 0.51 and 0.59 respectively), indicating substantial contribution by the globulins. A working formula suggesting approximate contribution of each gram of albumin and globulin in healthy subjects was calculated. It is inferred that the use of serum fructosamine for assessment of glycaemic status could be misleading in patients with lower albumin values. Calculating serum fructosamine values from serum albumin alone in these patients is likely to be inaccurate, as it ignores the contribution of globulins which can be substantial in certain disease conditions. A gross idea regarding the glycaemic status can be obtained by comparing actual and calculated values of fructosamine from the formula.

Montaje y estandarización de la determinación de fructosamina sérica en el autoanalizador vitalab-200 / Mounting and standardization of serum fructosamine determinación in the autoanalyser vitalab 200

La cuantificación de fructosamina con fines asistenciales e investigativos se realizó a través de un procedimiento automatizado en un autoanalizador Vitalab-200. basado en el método del nitroblue tetrasolio (NBT) descrito por Johnson. La calibración del método se relizó con el patrón acuoso externo 1-deoxi 1 morfolino fructuosa, y se obtuvo una adecuada respuesta lineal que se corrobora por los resultados del análisis de regresión (r=1.00; p<0.0001). Los coeficientes de variación promedios obtenidos de los estudios de repetibilidad y reproducibilidad fueron 4.3% y 9.1% respectivamente. El estudio para el establecimiento de los rangos de referencia en sujetos normales y en pacientes diabéticos evidenció una distribución normal de valores para ambas poblaciones; el rango de valores de fructosamina obtenido para sujetos normales abarca de 0.5 a 1.3 mmol de fructosamina/L, y para pacientes diabéticos de 1,3 a 3,0 mmol de fuctosamina/L

Evaluation of diabetic control by using hemoglobin A1 and fructosamine.

Evaluation of diabetic control was performed by using fasting plasma glucose, hemoglobin A1 and fructosamine in 139 patients with diabetes mellitus, and 36 normal controls. A linear correlation of fasting plasma glucose with fructosamine and hemoglobin A1 was found. Using fasting plasma glucose alone was found to be inadequate to define good control. HbA1 and fructosamine had an acceptable sensitivity and specificity in assessment of diabetic control, although fructosamine was slightly less sensitive than HbA1. In patients with thalassemia, hemoglobin A1 levels were elevated in 18 of 19 patients. Fructosamine levels also gave misleading results since 6 to 19 patients had an elevated level and one patient had a decreased level. Patients with hypoproteinemia had a decreased fructosamine and hemoglobin A1 level compared to normal control. HbA1 and fructosamine should be cautiously interpreted in patients with thalassemia and hypoproteinemic states. Using these methods in combination with other measure such as home monitoring of blood glucose would be more precise particularly in diabetic patients with hypoproteinemia, abnormal hemoglobin and other hemolytic disorders.

Serum fructosamine and glucose tolerance in diabetics with or without microangiopathy

This study included 25 healthy non-diabetic subjects [group I], as well as 40 diabetic patients. The diabetics were 20 patients without microangiopathy [group 11] and 20 patients with diabetic microangiopathy [group 111]. Plasma glucose levels during fasting as well as 2-hours after 75 g. Glucose oral load, serum albumin, fructosamine, urea, creatinine and the 24-hours unrinary albumin were estimated. In diabetics without microangiopathy [group 11], the means of serum fructosamine, the fasting as well as the 2-hours plasma glucose levels, and the 24 hours plasma glucose levels, and the 24 hours urinary albumin were significantly higher, while the mean of serum albumin was significantly lower than the corresponding means of controls [group 1]. Indiabetics with microangiopathy [group 111], the previous findings were also present, but to a significantly greater extent only with respect to the levels of fasting plasma glucose and the urinary albumin contents. The means of the other investigated parameters were not significantly different among the two groups of diabetic patients. In addition, diabetics with or without microangiopathy who showed relatively high fasting plasma glucose levels, showed also relatively high serum fructosamine and vice versa.1 Moreover, serum fructosamine levels showed significantly positive correlation with the fasting plasma glucose levels in controls and both groups of diabetics. However, serum fructosamine levels of each group showed no significant correlation with age, body weight, serum urea, creatinine, 24 hours urinary albumin, or the presence of microangiopathic complications. Thus, in conclusion, fructosamine levels were significantly elevated in this study, this elevation was not related to the presence of diabetic microangiopathy, but most probably, it reflects the lack of glycaemic control in these patients. these findings point to the possibility of using serum fructosamine levels as marker for glycaemic control in diabetics

The assays of glycosylated proteins in haemoglobinopathies and theis use in screening for diabetes Mellitus

We compare the relative validity of HbA1c and fructosamine as indices of lon-term vlood glucose levels in populations with a common occurrence of haemoglobinopathies. In these patients, HbA1c levels are lower than AbA1c levels in non-haemoglobinopathy patients and do not reflect the glucidic status of the patients, unlike the fructosamine assay. This last test has a good potential to be used as a mass screening test for diabetes mellitus in the populations (Africa, Caribbean, USA) in either homozygous or heterozygous haemoglobinopathy patients. Moreover, fructosamine presents numerous technical advantages which facilitate the screening

Serum protein-bound hexosamine in tumours of the genital tract

Serum protein-bound hexosamine was estimated in one hundred and four women. In patients with fibroid uterus there was an increase in its level. In the malignancy group of patients there was a highly statistically significant increase in its mean than that of controls. Its level could be of value in early detection of cancer body