Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The correct identification of Tay-Sachs heterozygotes requires a reliable procedure for separation and quantiation of the hexosaminidase isozymes. The most commonly employed method involves thermal inactivation of the heat labile hexosaminidase A assay of residual enzyme activity. This procedure, however, consistently yields a significantly lower absolute and relative activity of hexosaminidase A and a higher activity of the thermostable components (B and I) in comparison with the results obtained by DEAE-cellulose chromatography. DEAE-cellulose chromatographic separation of the hexosaminidase isozymes in serum following thermal inactivation reveals the presence of relative and absolute increase in the activity of the B and I components in addition to loss of the heat-labile A isozyme. Because the conversion of hexosaminidase A into thermostable forms by heating may vary according to the conditions employed, the thermal inactivation procedure may lead to ambiguity in heterozygote identification. This difficulty can be minimized by fractionation of the hexosaminidase isozymes by DEAE-cellulose chromatography followed by assay of the individual components. In addition to the Tay-Sachs carrier state, other conditions can alter the distribution of the hexosaminidase isozymes in tissues and body fluids. For example in serum of patients with juvenile diabetes mellitus there is a characteristic elevation of hexosaminidase B and less consistently, of hexosaminidase A. Since the activity of hexosaminidase A in serum of diabetics fractionated by ion exchange chromatography is at least as high as the activity in serum of healthy non-carriers, patients with diabetes can be easily differentiated from Tay-Sachs heterozygotes. Similarly, the distribution of the hexosaminidase isozymes in serum is altered during pregnancy, where there is usually a significant rise in hexosaminidase A and I (P). However, during pregnancy activities of hexosaminidase A and I in serum of obligate Tay-Sachs carriers are only 50% of the values observed in non-carriers at comparable gestational periods. Since the absolute activities of hexosaminidase A in serum of pregnant carriers obtained by ion exchange chromatography do not overlap with the activities in serum of non-carrier pregnant women at comparable gestational periods, this method has obvious advantages for identification of pregnancies where the fetus may be at risk for Tay-Sachs disease.
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PMID:Human hexosaminidase isozymes: chromatographic separation as an aid to heterozygote identification. 85 88

We determined the prevalence of 24 antigens controlled by the HLA-A and B loci in twenty patients with juvenile diabetes mellitus (JDM), in twenty patients with coeliac disease (CD), and in eight patients with both of these diseases. The prevalence of HLA-B8 was increased in JDM chi2 = 12.52, p = 0.00040) and in CD (chi2 = 26.47, p less than 0.000001) as compared to 900 controls. There was only a modest increase of Bw15 in JDM (chi2 = 8.86, p = 0.0029) and in patients with both diseases (chi2 = 2.72). The observed prevalence of phenotype HLA-B8, Bw15 was enhanced in JDM (chi2 = 16.03, p = 0;000063) and in patients with both JDM and CD (chi2 = 24.48, p = 0.00000074) as compared with controls. In the latter group the observed value was 2.2 fold to that expected. In family studies the children having both B8 and Bw15 were more disposed to develop diabetes than siblings with only one of these antigens. In conclusion, the inherited susceptibility to develop juvenile diabetes is markedly associated with HLA-B8 and slightly with HLA-Bw15, and that of coeliac disease with HLA-B8 in Finnish paediatric patients. The presence of both B8 and Bw15 simultaneously increases the susceptibility to have both JDM and CD.
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PMID:HLA antigens in patients with juvenile diabetes mellitus, coeliac disease and both of the diseases. 87 Mar 55

There is a significant positive association between insulin dependent diabetes, irrespective of age of onset, and the HLA system, whereas there is no association of HLA antigens with non-insulin dependent diabetes. There is a significant concordance value for HLA antigen frequencies in insulin dependent diabetics from three different centres, indicating that the genes (s) conferring susceptibility to this type of diabetes is possibly present in all "juvenile-onset" diabetics and is in linkage disequilibrium with all the B locus alleles.
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PMID:The HLA system and diabetes mellitus. 89 29

The leucocyte migration inhibition test (LMT) using the agarose plate method introduced by Clausen is simple and highly reproducible. Using human pancreas extract and beef insulin as antigen, LMT was performed on ten patients with insulin dependent diabetes, twenty patients with insulin independent diabetes, and twelve healthy controls. The migration index was expressed as a percentage of migration calculated from the following formula. Migration index (MI) = average areas of migration in test suspension/average areas of migration in control suspension. Using human pancreas extract, the mean migration index for the insulin dependent diabetics (87.6 +/- 11.1) was significantly lower than in the normal subjects (99.3 +/- 6.3) (p less than 0.05). Using beef insulin as antigen for the insulin dependent diabetics and insulin independent diabetics, the mean migration indices (+/- SD) were 95.8 +/- 14.9 and 98.7 +/- 12.3 respectively. The corresponding values for the control group were 98.9 +/- 7.8. Cellular hypersensitivity to human pancreas extract was shown in the leucocyte migration inhibition test with insulin dependent diabetics, but a negative result was obtained with beef insulin.
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PMID:[Leucocyte migration inhibition test in diabetes mellitus (author's transl)]. 91 18

A close correlation between juvenile mellitus and HLA-B8, HLA-BW15 and HLA-CW3 was found. Association of these antigens with juvenile diabetes mellitus was closely dependent on the ages of onset of the disease. Frequencies of BW15 and CW3 showed a remarkably low incidence in the childhood diabetics (0-15 years old) and were found increased in the patients with later (16 years or older) onset diabetes. HLA-B8 frequencies were found increased in all the groups of diabetics with different ages of onset. These findings point to the importance of HLA-B8 in childhood and HLA-B8, BW15 and CW3 in the later onset juvenile onset diabetes mellitus (JOD).
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PMID:Juvenile diabetes mellitus: HLA-antigen frequencies dependent on the age of onset of the disease. 93 67

In 25 diabetics and 8 controls the insulin hypoglycemia test was performed with subsequent determination of growth hormone secretion by the radioimmunoassay method. The rise of the growth hormone level began earlier and persisted longer in diabetics as compared with controls. Juvenile diabetes was associated with a rapid secretory response of the hormone while in maturity-type diabetes the release of growth hormone in response to stimulation was excessive but delayed. A somewhat lower secretory response was found in diabetes lasting over 5 years as compared with short-lasting diabetes. The observed phenomena were not related to the absolute blood glucose level. Although the phenomenon of growth hormone hypersecretion remains yet to be explained, it seems, however, to be secondary to carbohydrate metabolism disturbance and insulin disorders.
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PMID:Secretion of growth hormone in the insulin test in various forms of diabetes. 95 43

HLA-A and B antigens were determined in 112 patients with insulin-dependent juvenile onset diabetes mellitus, who could be subdivided into "non" and "high responder" to insulin. The data revealed a trend of an association of these diabetes subgroups with only one of the diabetes-associated antigens HLA-B8 and HLA-BW15 and indicated the existence of at least two different genetic constellations for susceptibility to juvenile diabetes mellitus. One form with a strong immune-response to insulin seemed to be associated with HLA-BW 15 and the other form without humoral immunoreactivity to insulin seemed to be associated with the presence of HLA-B8 and the absence of HLA-B7.
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PMID:HLA antigens and immunoresponsiveness to insulin in insulin-dependent diabetes mellitus. 96 73

Cholesterol, triglyceride, and lipoprotein levels were determined in serum from 40 children with diabetes and from controls. Mean cholesterol levels in the children with diabetes (205 +/- 78 mg/dl) were statisically higher than for controls (155 +/- 27 mg/dl), as were mean triglyceride levels (120 +/- 63 vs 85 +/- 23 mg/dl). Eight of the children with diabetes had hypercholesterolemia, five had hypertriglyceridemia, and nine had combined hypercholesterolemia and hypertriglyceridemia. Low-density lipoprotein levels were statistically higher and high-density lipoprotein levels statistically lower for children with diabetes compared with control children. Increased urine glucose spillage was found to correlate with higher serum triglyceride levels, suggesting that the elevated triglyceride levels may have been related to diabetes control. With the known association between hyperlipidemia and coronary heart disease (CHD) and between diabetes and CHD, the results of the present study indicate that all children with juvenile diabetes mellitus should have a serum lipid analysis annually.
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PMID:Juvenile diabetes mellitus and serum lipids and lipoprotein levels. 97 14

In this study, 37 guinea pigs were classified, on the basis of histologic examination of the pancreas, into three categories: nondiabetic, latent diabetic, and overt diabetic. In order to compare the exocrine pancreatic function in these three groups of animals, pancreatic secretion was collected from each animal following an intravenous infusion of secretin and pancreozymin. Pancreatic enzyme activity, bicarbonate concentration, and the total volume of pancreatic secretion were all significantly decreased in guinea pigs with overt diabetes, but not in those with latent diabetes mellitus. Pancreatic histologic changes characteristic of both latent and overt diabetes were beta-cell hyperplasia and generalized fatty degeneration of the acini. Only the animals with overt diabetes showed total degranulation and severe vacuolation of theta-cells. The same type of exocrine pancreatic dysfunction observed in guinea pigs with spontaneous overt diabetes mellitus is found in human diabetics, and is particularly common in the juvenile type. The guinea pig, therefore, appears to be a suitable animal model for the study of human juvenile diabetes mellitus.
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PMID:Exocrine pancreatic dysfunction in guinea pigs with diabetes mellitus. 108 36

The effect of juvenile onset diabetes mellitus on quadriceps muscle capillary basement membrane (QCBM) width has been examined by the electron microscopic morphometric method previously developed in this laboratory. The results demonstrate that in this age group QCBM thickening is strongly related to the age of the diabetic subject. As a result, in contrast to the almost constant thickening of QCBM that has consistently been documented in diabetic adults, QCBM hypertrophy is present in only 40 per cent of children with diabetes mellitus. As was previously shown to be the case in adults, in children, too, QCBM thickening is unrelated to the duration of the diabetes. Finally, the finding that QCBM hypertrophy is present at the time of acute onset of juvenile diabetes mellitus in 30 per cent of children, coupled with the fact that this lesion is not affected by duration of hyperglycemia, strongly supports our previous conclusion that diabetic microangiopathy is independent of the hyperglycemia of this disease. On the other hand, barring the possibility that microangiopathy in the pancreas precedes that in muscle, these results represent evidence against the suggestion that basement membrane hypertrophy represents the primary lesion of the diabetic syndrome.
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PMID:Capillary basement membrane width in diabetic children. 111 75


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