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Biomedical subjects

J Terpstra

Publications and source records attributed to J Terpstra.

10 recordsLinked to original sources
PubMed1979

Photocoagulation treatment in diabetic retinopathy: a two-year pre- and five-year post-treatment study.

A randomized controlled study covering a two-year pre-treatment and a five-year post-treatment period was performed in 42 patients with diabetic retinopathy given photocoagulation treatment in one eye. Patients with progressive diabetic retinopathy of equal intensity in both eyes were selected from a single diabetes department. The course of diabetic retinopathy was assessed by ophthalmoscopy and composite fundus photographs as well as fluorescence angiography. In the first two-year post-treatment period non-proliferative retinopathy improved in the coagulated eyes and also, albeit to a lower degree, in the control eyes. In the next three years the treated eyes showed further improvement or stabilization, whereas the control eyes showed either stabilization or deterioration of the retinopathy. The most favourable results were obtained in proliferative diabetic retinopathy, which regressed in the majority of the eyes, the other eyes remaining stable or progressing only very slightly, in contrast with the control eyes, in the great majority of which proliferative diabetic retinopathy developed or progressed.

Adult↗
PubMed1979

Influence of meal frequency on diurnal lipid, glucose and insulin levels in normal subjects on a high fat diet; comparison with data obtained on a high carbohydrate diet.

Diurnal levels of serum triglyceride (TG) were measured in six normal persons consuming a fixed solid 65% fat diet under steady state conditions in a metabolic unit. The food was divided into either three or eight similar portions, differently spaced over the day and night. The diurnal TG-profiles on this diet were practically identical to those found under comparable conditions on a 65% carbohydrate diet [1]. Mean diurnal TG values did not significantly differ with varying meal frequency. Free fatty acid levels, however, were significantly higher on a high fat diet. Post-prandial glucose and insulin reponses did not significantly differ whether a high fat diet or a high carbohydrate diet was consumed. We conclude that the composition of the diet is of little importance in determining diurnal TG patterns when the diet consists of normal food stuffs, but that these patterns are dependent on meal frequency and distribution.

Blood Glucose↗
PubMed1978

The influence of meal frequency on diurnal lipid, glucose and cortisol levels in normal subjects.

Diurnal levels of serum triglyceride, cholesterol, free fatty acids, glucose, and cortisol were measured in four normal persons on a fixed solid 65% carbohydrate diet under steady state conditions in a metabolic unit. Triglyceride levels in all subjects showed similar patterns, which unexpectedly did not bear a simple relation to meal frequency or distribution. With three equivalent meals per day at 09.00, 12.00 and 17.00 hours, 'fasting' triglyceride levels increased by about 0.3 g/l from a minimum value between 03.00 and 05.00 hours in the morning till before breakfast. After breakfast there was a continued rise till about 15.00 hours and then a overall fall in spite of the meal at 17.00 hours. Isocaloric change to eight equivalent meals, consumed between 09.00 and 23.00 hours, resulted in a similar although slightly more even triglyceride pattern. On eight equivalent meals, spaced evenly over the entire 24 h period, a different pattern was found with lower triglyceride values at daytime than at night. Increase in meal frequency did not result in a lowering of mean diurnal triglyceride levels. The cholesterol pattern followed the triglyceride pattern most clearly in subjects with high triglyceride levels. Glucose showed the expected postprandial increments. Cortisol rhythm did not change on varying meal frequency.

Adult↗
PubMed1976

Some properties of a microsomal oleate desaturase from leaves.

1. When [1-14C]oleoyl-CoA was incubated with a pea-leaf homogenate oleate was both incorporated into microsomal 3-sn-phosphatidylcholine and released as the unesterified fatty acid. The proportion of oleate incorporated into this phospholipid was dependent on the relative amounts of thiol ester and microsomal preparation present in reactions. 2. At the concentrations of microsomal preparation and [14C]oleoyl-CoA used to study oleate desaturation the metabolism of the thiol ester was essentially complete after 5 min incubation, but the loss of label from 3-sn-phosphatidylcholine oleate and the concomitant increase in radioactivity in the linoleate of this phospholipid proceeded at approximately linear rates over a 60 min period. The kinetics of labelling of unesterified linoleate was consistent with the view that this labelled fatty acid was derived from 3-sn-phosphatidylcholine. 3. Oleate desaturation required oxygen and with unwashed microsomal fractions was stimulated either by NADPH or by the 105 000g supernatant. Washed microsomal preparations did not catalyse desaturation, but actively was restored by the addition of NADPH, 105 000G supernatant or Sephadex-treated supernatant. NADPH could be replaced by NADH or NADP+, but not by NAD+. 4. Microsomal fractions from mature and immature maize lamina and expanding spinach leaves also rapidly incorporated oleate from ([14C]oleoyl-CoA into 3-sn-phosphatidylcholine, but desaturation of 3-sn-phosphatidylcholine oleate was detected only with microsomal preparations from immature maize lamina. 5. It is proposed that leaf microsomal preparations posses an oleate desaturase for which 3-sn-phosphatidylcholine oleate is either the substrate or an immediate precursor of the substrate.

Acetates↗
PubMed1975

The incidence of diabetes mellitus in the offspring of diabetic couples. Investigation based on the oral glucose tolerance test.

88 of 137 offspring of 22 adult onset diabetic couples were subjected to an oral glucose tolerance test (G.T.T.); 35 were found to have a diabetic G.T.T. As 8 were already known as diabetics, 43 of 96 offspring (45%) were found to have diabetes mellitus. Neither the data pertaining to the parents, such as family history, treatment of diabetes or obstetric history, nor the data pertaining to the offspring, such as sex, age, parity or course of pregnancy, could be related to the incidence of diabetes in the offspring. It was noted however, that overweight female, but not male, offspring are more likely to develop diabetes than those who are not overweight (p less than 0.05).

Adolescent↗
PubMed1975

The effect of phenformin-HCl on patients with diabetes mellitus, studied under strict balance conditions.

Under strict balance conditions we studied the effect of phenformin in 5 patients with diabetes mellitus. In all cases phenformin lowered the blood glucose values, and all patients showed a reduction of glycosuria. Contrary to other reports body weight increased during phenformin treatment. This was accompanied by positive nitrogen, phosphorus and calcium balances. The weight gain can be explained by the positive caloric balance, mainly caused by the diminished glycosuria. No change in B.M.R. or R.Q. was seen. During phenformin treatment there was a drop in cholesterol and total lipid levels in 4 patients. No conclusions could be drawn about the effect of phenformin on triglycerides, phospholipids and lipoprotein spectra. Phenformin treatment did not affect the disappearance of glucose, nor the insulin levels after intravenous glucose loading. During oral glucose loading phenformin caused a significant fall in blood glucose levels, accompanied by an increased insulin response in one patient. In the other 4 patients phenformin had no effect on either parameter.

Aged↗