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C Schnack

Publications and source records attributed to C Schnack.

31 records · Page 2Linked to original sources
PubMed1992

Hypomagnesaemia in type 2 (non-insulin-dependent) diabetes mellitus is not corrected by improvement of long-term metabolic control.

Low levels of magnesium have frequently been reported in diabetes mellitus especially in poorly controlled Type 1 (insulin-dependent) diabetic patients. Furthermore hypomagnesaemia might contribute to insulin resistance in Type 2 (non-insulin-dependent) diabetes. As the influence of improved metabolic control on plasma magnesium levels is unknown in Type 2 diabetic patients we studied magnesium plasma levels in 50 patients 1) before, 2) one and 3) three months after the initiation of insulin therapy or intensified treatment with oral hypoglycaemic agents. Magnesium plasma levels were measured by a colorimetric method and were significantly reduced in diabetic patients compared to healthy control subjects (0.79 +/- 0.01 mmol/l vs 0.88 +/- 0.01 mmol/l; p less than 0.0001). Metabolic control was significantly improved as documented by reduced HbA1C levels in both insulin-treated patients or the patients on oral hypoglycaemic agents (p less than 0.003). However, plasma magnesium levels remained unchanged during the follow-up in the insulin-treated group (1: 0.79 +/- 0.02 mmol/l; 2: 0.81 +/- 0.02 mmol/l; 3: 0.79 +/- 0.01 mmol/l) as well as in the patients on oral hypoglycaemic agents (1: 0.79 +/- 0.03 mmol/l; 2: 0.78 +/- 0.02 mmol/l; 3: 0.84 +/- 0.04 mmol/l). This study shows that even marked improvement of glycaemic control does not correct hypomagnesaemia in Type 2 diabetes. We conclude that hypomagnesaemia might be related to the insulin-resistant state and that possible beneficial effect of chronic magnesium administration should be evaluated in these patients.

Blood Glucose↗
PubMed1991

[Decreased plasma carnitine in Type I diabetes mellitus].

Realizing the importance of carnitine for the lipid and carbohydrate metabolism and the possible role for glucose utilization and myocardial function carnitine concentrations in type I and type II diabetic patients in plasma, erythrocytes and 24 h urine were determined. The plasma levels of carnitine were significantly diminished in type I diabetic patients compared to controls, while carnitine concentrations in erythrocytes and 24 h urine did not differ from controls. Plasma carnitine levels did not change significantly during the diurnial profile. No correlation between HbA1c and carnitine levels was observed in the diabetic patients.

Adult↗
PubMed1991

Metabolic effects of isradipine versus hydrochlorothiazide in diabetes mellitus.

Most antihypertensive drugs have negative effects on metabolic control in diabetic patients. Calcium antagonists have been widely used in antihypertensive treatment of diabetics, although a possible influence on glucose tolerance, insulin secretion, and insulin action is unknown. Therefore, the effect of the calcium antagonist isradipine on glucose tolerance and insulin secretion (75 g oral glucose tolerance test) and on peripheral and hepatic insulin action (euglycemic clamp) was evaluated in 11 type II diabetic patients. All patients were treated with placebo or isradipine for 8 weeks (double-blind, crossover design). A second group of six diabetic patients received a thiazide diuretic, hydrochlorothiazide, according to the same protocol. Systolic blood pressure was significantly lowered after isradipine and hydrochlorothiazide compared with placebo (127 +/- 3 versus 139 +/- 6 mm Hg and 129 +/- 4 versus 142 +/- 4, respectively; p less than 0.05). Fasting blood glucose (190 +/- 21 versus 152 +/- 15 mg/dl; p less than 0.01), glucose levels, basal and glucose-stimulated insulin levels were significantly higher after hydrochlorothiazide compared with placebo but remained unchanged after calcium antagonist treatment. Basal hepatic glucose production and peripheral insulin resistance were significantly elevated after hydrochlorothiazide compared with placebo or calcium antagonist therapy. These data indicate that the calcium antagonist isradipine has no effect on glucose tolerance, insulin secretion, and insulin action in type II diabetic patients and might therefore be a useful drug for antihypertensive treatment in diabetes mellitus. However, diuretic treatment can lead to impairment of metabolic control and reduction of insulin action in type II diabetes mellitus.

Adult↗
PubMed1991

Decrease of stimulated amylin release precedes impairment of insulin secretion in type II diabetes.

Amylin, a 37-amino acid polypeptide, has been identified as the major protein component of pancreatic amyloid deposits in patients with non-insulin-dependent (type II) diabetes mellitus. Amylin is stored and released together with insulin and has been proposed to play a major role in the pathogenesis of type II diabetes. To compare amylin release and its proportion to insulin secretion under different metabolic conditions, oral and intravenous glucose tolerance tests (OGTT and IVGTT, respectively) were performed in healthy, lean control subjects, obese patients with normal and impaired glucose tolerance (NGT and IGT, respectively), and obese type II diabetic patients. Compared with control subjects, basal and stimulated amylin secretion during OGTT was significantly higher in obese patients with NGT and IGT but not in type II diabetic patients. The integrated amylin response was significantly higher in obese patients with NGT than lean control subjects and type II diabetic patients matched for degree of obesity. The amylin-insulin ratio decreased slightly in obese subjects with NGT and IGT and significantly in type II diabetic patients. Amylin secretion was significantly stimulated during IVGTT in control subjects and obese patients with NGT and IGT but not in type II diabetic patients. These findings suggest that amylin is physiologically released by pancreatic beta-cells in a constant ratio to insulin in nondiabetic subjects. Glucose-stimulated amylin secretion is increased in obese subjects with NGT and IGT. In type II diabetes mellitus, amylin secretion relative to that of insulin is decreased, and amylin is not stimulated by IVGTT.

Adult↗
PubMed1991

[Effect of structured ambulatory training of patients with chronic respiratory tract diseases on the efficiency of long-term care].

In spite of the availability and widespread use of a number of effective medications, the frequency of severe attacks of asthma bronchiale including those with fatal outcome has not decreased. One possible reason for this is the delay in therapeutic intervention of up to 30 minutes resulting either from transport time to a hospital or from the response time of mobile ambulance services. Treatment delays are also frequent co-factors for decreased well-being in non-emergency cases. Prompt initiation of countermeasures, regardless of time or place, can only be guaranteed when the patient himself is capable of carrying them out with the same expertise as his attending physician. Toward this end, a model patient-training program was investigated. The didactic goal of the training was to make the patient an expert in his chronic disease. The medical goal of the training was to improve the quality of a complex long-term therapy and with it, the patient's well-being and quality of life. The content of the training corresponded largely to that contained in a lecture series for medical students or physicians on the same subject. Style and choice of words (avoidance or explanation of medical terminology) was of course adapted to the lay-status of the patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Psychological↗
PubMed1989

Effects of somatostatin and oral potassium administration on terbutaline-induced hypokalemia.

Terbutaline, a beta 2-adrenergic agonist, has been shown to cause hypokalemia and an increase of plasma glucose and serum insulin concentrations. We considered that terbutaline-induced hypokalemia may be due to the insulin-induced shift of potassium (K+) from the extracellular to the intracellular space. If so, then inhibition of insulin secretion by somatostatin would prevent terbutaline-induced hypokalemia. Further, we wondered whether oral potassium pretreatment could prevent terbutaline-induced hypokalemia. Therefore, 10 healthy volunteers (5 men, 5 women; mean age, 23 yr +/- 3 SD) received either sodium chloride (NaCl) or somatostatin intravenously together with 0.25 mg terbutaline subcutaneously in a double-blind crossover design. On a third test day, they received 39 mval of K+ powder orally before terbutaline injection in an open trial. Terbutaline caused a significant decrease of K+ (from 3.96 +/- 0.08 to 3.3 +/- 0.13 mmol/L +/- SEM; p less than 0.0005), accompanied by a significant increase in plasma glucose (from 83 +/- 3.6 to 101 +/- 4.4 mg/dl +/- SEM; p less than 0.01) and serum insulin concentrations (from 11.7 +/- 0.9 to 19.9 +/- 1.1 microU/ml +/- SEM; p less than 0.001), confirming earlier data. Somatostatin pretreatment inhibited the terbutaline-induced hypokalemia; the small fall of K+ (from 3.7 +/- 0.08 to 3.5 +/- 0.2 mmol/L) was no longer significant. Insulin secretion was completely blocked by somatostatin, leading to an even more pronounced increase of blood glucose. Hypokalemia after terbutaline injection was not prevented by oral potassium pretreatment. In summary, the present findings confirm that terbutaline-induced hypokalemia is associated with increased plasma glucose and insulin levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1989

Effects of 8-wk alpha-glucosidase inhibition on metabolic control, C-peptide secretion, hepatic glucose output, and peripheral insulin sensitivity in poorly controlled type II diabetic patients.

Miglitol (BAYm 1099), an alpha-glucosidase inhibitor, reduces the postprandial increase of blood glucose and serum insulin levels in type II (non-insulin-dependent) diabetes mellitus, as shown in short-term studies. In this study, the effects of long-term miglitol treatment on metabolic control, C-peptide secretion, hepatic glucose output, and peripheral insulin sensitivity (euglycemic clamp) were tested in 15 type II diabetic patients (8 receiving insulin, 7 receiving oral hypoglycemic agents). For 8 wk they received either miglitol (300 mg/day) or placebo with a double-blind crossover design that had a 4-wk washout period between treatments. Miglitol therapy induced a reduction of postprandial blood glucose levels (miglitol compared with placebo; areas under the curve; P less than .002), whereas fasting blood glucose levels were not influenced. Miglitol caused a slight reduction of glycosylated hemoglobin levels (mean +/- SE miglitol and placebo 9.50 +/- 0.3 and 10.0 +/- 0.4%, respectively; P less than .05), which was more pronounced in insulin-treated patients. Miglitol caused a reduction of postprandial C-peptide increase (P less than .03). Hepatic glucose output (both in the basal state and during euglycemic clamp conditions) and peripheral insulin sensitivity were not influenced by miglitol therapy. Specific side effects were observed in 11 patients; in 6 patients only to a moderate degree. Long-term miglitol treatment induces a persistent reduction of postprandial blood glucose increase. This effect is more pronounced in type II diabetic patients on insulin therapy, which can cause a moderate improvement of overall metabolic control.

1-Deoxynojirimycin↗
PubMed1988

[Significance of arterial blood pressure for the development of microalbuminuria and retinopathy in type I diabetes mellitus].

The role of hypertension for the combined occurrence of incipient diabetic nephropathy and diabetic retinopathy (RP) was evaluated in 155 insulin-dependent diabetic patients (74 male/81 female); mean age 32.4 +/- 12.2 STD years; means diabetes duration 12.8 +/- 10 STD years). Albumin excretion rate (AER) was measured in 24 hours urine samples by RIA, retinal status was determined by both, fundoscopy and fluorescein angiography. Analysis of the data revealed a statistically significant correlation between the duration of disease and elevated AER (p less than 0.012), and the occurrence of retinopathy (p less than 0.0001). Although there was a close correlation between retinopathy and elevated AER (p less than 0.0001), it is remarkable that 31% of the patients with normal AER (less than 15 micrograms/min) showed signs of non proliferative RP. On the other hand 30% of patients without retinal changes showed an elevated AER (less than 15 micrograms/min). In the group of microalbuminuric patients (greater than 15 micrograms/min) systolic (p less than 0.004) and diastolic (p less than 0.04) blood pressures were significantly higher than in normoalbuminuric patients (less than 15 micrograms/min). Patients with proliferative retinopathy showed significantly higher systolic and diastolic (p less than 0.015) blood pressures compared to patients without retinal changes, though albumin excretion rates were not different in both groups of patients. In conclusion, our results show that diabetic nephropathy and diabetic retinopathy do not develop simultaneously in a representative number of insulin-dependent diabetic patients, but hypertension may be a major risk factor for the development of both microangiopathic complications.

Adolescent↗
PubMed1988

Coagulation factors of contact phase of haemostasis are normal in well-controlled type-I diabetic patients despite presence of diabetic retinopathy.

Alterations of plasma coagulation factors have been reported in diabetic patients with severe microangiopathy and metabolic derangement. No information is available, however, for well-controlled type-I diabetic patients. Thus, we studied coagulation factors of the contact phase and inhibitors in 80 fairly well-controlled diabetics (42 female, 38 male, age 28 +/- 11 SD years). Mean HbA1c in these patients was 6.6 +/- 1.0 SD, duration of diabetes ranged from 6 months to 30 years, and 36% had retinopathy shown by fluorescein angiography. The well-controlled diabetic patients did not differ from controls in terms of the activity of prekallikrein, factor XII, high molecular weight kininogen, kallikrein inhibitor, C-1-esterase inhibitor and antithrombin III. Only alpha-2-macroglobulin, an inhibitor of the contact phase of blood coagulation, was elevated significantly in these patients (p less than 0.05). Diabetics with retinopathy had similar activities of prekallikrein, factor XII, high molecular weight kininogen, kallikrein inhibitor, c-1-esterase inhibitor and antithrombin III when compared with patients without retinopathy and controls respectively. alpha-2-macroglobulin did not differ in patients with and without diabetic retinopathy but were significantly elevated in both groups compared with controls. Correlation analysis showed significant positive correlation between HbA1c and the activity of high molecular weight kininogen, kallikrein inhibitor and alpha-2-macroglobulin. In patients with poor metabolic control (n = 11; 6 female, 5 male; age 25 +/- 5 SD years; HbA1C 10.7 +/- 0.9) prekallikrein (p less than 0.05), kallikrein inhibitor (p less than 0.005) and alpha-2-macroglobulin (p less than 0.005) were significantly elevated compared to the controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Pituitary thyrotroph function and thyroid hormones in longstanding type-II diabetes mellitus before and after insulin treatment.

We investigated the TRH induced TSH secretion and thyroid hormone concentrations in 14 type-II diabetics with secondary failure to oral hypoglycemic agents (mean age: 70.8 years, range: 55-77, mean duration of disease: 11 years +/- 7.9 SD, mean HbAlc: 10.1 +/- 1.6 SD) with normal body weight before and after insulin therapy. Results were compared with those of healthy control persons. Before insulin treatment T3 and fT3 concentrations were significantly lower in diabetics (p less than 0.05) compared to controls, rT3 was slightly elevated in diabetics. With improved metabolic control following insulin treatment T3 and fT3 slightly increased, whereas rT3 slightly decreased. Basal TSH concentrations and TRH induced TSH secretion were not altered in diabetics compared to controls and were not influenced by insulin therapy. The alterations of peripheral thyroid hormone concentrations seem to be caused by reduced peripheral deiodination of T4 to T3 with increased production of rT3. Pituitary thyrotroph function is normal in long-standing type-II diabetic patients with normal body weight.

Adult↗
PubMed1986

Effects of the alpha-glucosidase inhibitor 1 desoxynojirimycin (Bay m 1099) on postprandial blood glucose, serum insulin and C-peptide levels in type II diabetic patients.

Bay m 1099 is a newly developed inhibitor of intestinal alpha-glucosidase. Its ability to lower postprandial plasma glucose, serum insulin and C-peptide levels in Type II diabetics has been investigated. Fifteen obese Type II diabetic patients with inadequate metabolic control during sulphonylurea treatment received a standardized diet and were treated either with Bay m 1099, b.d. (100 mg before breakfast and dinner) or placebo for 3 days, according to a double-blind cross-over design. The postprandial blood glucose level was significantly lower during Bay m 1099 treatment compared to placebo after breakfast and dinner (AUC after breakfast p less than 0.001). The reduced postprandial hyperglycaemia was associated with a decrease in meal stimulated serum insulin and C-peptide levels. Thus, Bay m 1099 may be a useful addition in the treatment of Type II diabetic patients.

1-Deoxynojirimycin↗
PubMedDate not supplied

Prevalence of microalbuminuria in maturity onset primarily non-insulin-requiring diabetes mellitus: effect of disease duration, glycemic control, and mean systemic blood pressure.

Because of the frequency of late cardiovascular complications in maturity onset non-insulin-dependent (Type II) diabetes mellitus, there have been few studies regarding nephropathy in this patient population. The authors have analyzed the prevalence of microalbuminuria and the nature of clinical manifestations associated with elevated albumin excretion rate (AER) in a large population presenting with Type II diabetes. Among 318 patients studied during 1986, pathologically elevated 24 h AERs were found in 59%. The rate of microalbuminuria among 205 Type I diabetic patients screened during the same interval was 43%. AER was found to be positively correlated with duration of disease (p less than 0.0008) and metabolic control as determined by measurement of glycosylated hemoglobin (HbA1c) (p less than 0.002). There was only a modest agreement between AER and mean systemic blood pressure. The high prevalence of microalbuminuria in Type II diabetic patients and its known association with increased mortality emphasize the need for long-term follow up studies in order to clarify whether elevated AER in this patient population is predictive for overt diabetic nephropathy.

Adult↗