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Biomedical subjects

J Veenstra

Publications and source records attributed to J Veenstra.

At least 55 records · Page 3Linked to original sources
PubMed1993

Alternative splicing generates diversity of VD1/RPD2 alpha peptides in the central nervous system of Lymnaea stagnalis.

1. Two giant peptidergic neurons, VD1 and RPD2, of the visceral ganglion and right parietal ganglion of Lymnaea stagnalis, respectively, play an important role in the modulation of complex physiological and behavioral adjustments that occur as a result of changes in O2 availability. 2. By cDNA cloning, we have identified two types of VD1/RPD2 transcripts expressed in VD1 and RPD2. In addition, these transcripts are also expressed in other neurons. 3. Both transcripts encode distinct yet related VD1/RPD2 preprohormones that may be cleaved to yield distinct but overlapping sets of neuropeptides. 4. Using the polymerase chain reaction technique, we could show the existence of additional splice variants. 5. Analysis of the organization of the VD1/RPD2 gene indicates that the alpha peptide coding region is interrupted by a number of introns. 6. We concluded that the mRNA segment encoding the alpha peptide domain of the VD1/RPD2 preprohormones is alternatively spliced, thus generating different alpha peptides.

Amino Acid Sequence↗
PubMed1993

An inventory of the alcohol research literature.

This paper provides an inventory of the literature on alcohol research. The aim is to provide the readers of this literature with data on the quantity and types of papers published. For this purpose, over 4000 scientific papers on biomedical and social aspects of alcohol consumption, which had been collected in our Alcohol Documentation Centre over the past 2 years, were surveyed. They were classified according to three criteria: (1) the subject under investigation, (2) the type of study, and (3) whether the study concerned normal consumption, alcohol misuse or both. Furthermore, information is given on sources of alcohol research literature, authorship, and countries of origin.

Alcohol Drinking↗
PubMed1993

Alcohol consumption in relation to food intake and smoking habits in the Dutch National Food Consumption Survey.

The interrelationships between alcohol consumption, energy and food intake and smoking habits were studied in 1145 men and 1171 women, aged 22-49 years, in the Dutch National Food Consumption Survey, in which a 48-h dietary record method was used. The aim of the study was to investigate the effects of alcohol consumption on dietary habits and smoking. A strong relationship between alcohol consumption and energy intake was found. The energy derived from alcohol was not compensated for by lower intake of other nutrients. There was no increase in Quetelet's index with increasing alcohol consumption, except for non-smoking men who were heavy drinking on midweek days. Possible explanations for this apparent lack of an overall effect of alcohol calories are discussed. Alcohol consumption was much higher on weekend days than on midweek days. No differences in nutrient intake were found between non-drinkers, moderate drinkers and heavy drinkers on midweek days. On weekend days, however, there was a slightly higher total fat and saturated fat intake in moderately drinking men. For women cholesterol intake was found to be higher in moderate and heavy drinkers. Finally, a strong positive relationship between alcohol consumption and smoking was observed. It is concluded that the observations with respect to energy and nutrient intake and smoking habits are not indicative of a healthier lifestyle in moderate alcohol users between 22 and 49 years of age. Consequently, the more favourable prognosis of moderate drinkers cannot be ascribed to a more healthy lifestyle.

Adult↗
PubMed1991

[Accessory spleens as a cause of recurrent idiopathic thrombopenia].

A female aged 62 yr developed a recurrence of chronic idiopathic thrombocytopenia 7 years after splenectomy. Two accessory spleens were identified and removed surgically. An increase in platelet count was seen. An analysis of the literature shows that extirpation of accessory spleens was successful in over 60% of the patients (32/52) with recurring idiopathic thrombocytopenia after splenectomy.

Choristoma↗
PubMed1991

Do alcoholic beverages have an additional effect on the postprandial gastrin response in humans?

The hormone gastrin plays an important role in the regulation of acid secretion in the stomach which, in turn, stimulates the digestion of food. Previous studies reported that administration of beer and wine but not ethanol and spirits increases gastrin secretion in fasting volunteers. It is not known whether alcoholic beverages combined with a normal meal have an additional effect on the postprandial gastrin response. We therefore measured the gastrin response in eight volunteers who received either alcoholic beverages (40 g alcohol) in the form of beer, red wine or spirits, or mineral water as control in combination with a dinner. Two glasses were drunk before the meal, two glasses during the meal. Plasma gastrin concentrations were twofold increased at one hour after the dinner as compared to predinner values. However, no additional effect of beer, wine or spirits on this postprandial response was seen. The present study does not support the hypothesis that the consumption of beer or wine during a meal has a positive effect on the release of gastrin and therefore most probably does not contribute to an improved digestion of food by stimulation of acid secretion.

Alcohol Drinking↗
PubMed1991

Serum IgG and IgA anti-gliadin antibodies as markers of mucosal damage in children with suspected celiac disease upon gluten challenge.

Serum anti-gliadin antibodies (AGAs) of the IgG and IgA isotypes were determined in 17 children (mean age of 5.6 years) by means of an enzyme-linked immunosorbent assay (ELISA). All children were suspected of celiac disease. They had been on dietary treatment for at least 10 months before they were challenged with gluten. Based on jejunal biopsy findings, 10 of the 17 children had to be considered positive. The sensitivity of the measurement of AGA at 6 weeks after gluten challenge was found to be 90% for IgG, 100% for IgA, and 100% for IgG/IgA combined. The specificity for IgG, IgA, and the IgG/IgA combination was 100, 71, and 100%, respectively. Twelve weeks after gluten challenge, the sensitivity as well as the specificity of AGA determination for IgG, IgA, and IgG/IgA were 100%. It is concluded that testing both IgG AGA and IgA AGA in children suspected of celiac disease is valuable in monitoring the course of the diagnostic provocation protocol and that jejunal biopsies can be abolished. This inexpensive tool can be useful in reducing the number of intestinal biopsies.

Adolescent↗
PubMed1991

Effect of antihypertensive drugs on insulin absorption.

OBJECTIVE: To examine the effects of antihypertensive drugs on the absorption of subcutaneously injected insulin. RESEARCH DESIGN AND METHODS: Eleven healthy volunteers (group 1) were given 1 mg/kg body wt propranolol three times a day during 48 h and a single dose on the morning of investigation. Seven other healthy volunteers (group 2) were given 10 mg nifedipine 30 min before subcutaneous injection of 10 U 125I-labeled soluble insulin. Absorption was measured by counting radioactivity externally. In both groups, control experiments were conducted under the same conditions without administration of propranolol or nifedipine. RESULTS: Propranolol usage was associated with higher mean percentages of remaining activity (P less than 0.05 by analysis of variance [ANOVA]) than in the control experiment. In the nifedipine experiment, mean percentages were significantly lower compared with the control experiment (P less than 0.02 by ANOVA). The mean decline in activity of all 30-min periods was 6.8 +/- 3.5 vs. 3.6 +/- 3.7% for control versus propranolol (group 1) (P less than 0.05) and 6.3 +/- 1.8 vs. 9.6 +/- 3.2% for control versus nifedipine (group 2) (NS). CONCLUSIONS: Antihypertensive drugs can influence insulin absorption. Propranolol (a peripheral vasoconstrictor) decreases insulin absorption, whereas nifedipine (a vasodilatator) increases insulin absorption.

Absorption↗
PubMed1990

Effects of moderate alcohol consumption on platelet function, tissue-type plasminogen activator and plasminogen activator inhibitor.

Short-term effects of moderate alcohol consumption on platelet function, tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) were studied in two age groups of volunteers (20-30 and 45-55 years), each consisting of eight healthy males. The alcohol (30 g in red port and wine) was consumed during a standard dinner. Two blood samples were drawn: one in the postprandial phase, and one the next morning after fasting overnight. Alcohol consumption tended to increase platelet aggregation and production of hydroxy fatty acids, reduced plasma t-PA activity and increased PAI activity in the postprandial phase. After the overnight fast the effects on t-PA and PAI had disappeared whereas at that time alcohol consumption tended to decrease platelet function. The effects of alcohol on t-PA and PAI activity appeared mainly in the older age group, whereas the t-PA activity in this group was already much lower, irrespective of alcohol consumption.

Adult↗
PubMed1990

[Myocardial infarct following use of amphetamine derivatives].

Development of an acute myocardial infarction is described in two previously healthy men of 25 and 40 years respectively, shortly after taking oral amphetamine derivatives. Coronary angiography disclosed in both men a normal coronary system without stenoses or irregularities. Ventriculography revealed in both a segmental dysfunction of the left ventricle. A relationship is postulated between use of amphetamine and occurrence of acute myocardial infarction in the absence of coronary artery disease.

Adult↗
PubMed1990

Effects of a moderate dose of alcohol on blood lipids and lipoproteins postprandially and in the fasting state.

Effects of a moderate dose of alcohol on blood lipids and lipoproteins were studied in volunteers of two age groups (20-30 and 45-55 years), each consisting of eight healthy men. The alcohol (30 g in red port and wine) was consumed during a standard dinner. Two blood samples were drawn: one in the postprandial phase, and one the next morning after fasting overnight. In the postprandial phase, one hour after intake, alcohol increased high-density lipoprotein cholesterol (HDL-C) by 11.5%, triglycerides (TG) by 15.3% and apolipoprotein A2 (Apo-A2) by 7.3% (P = 0.002, P = 0.044 and P = 0.024, respectively). The increase in HDL-C appeared to be mainly attributed to the HDL2-C subfraction which increased by 15.3% (P = 0.066). Furthermore, the increases in HDL-C, HDL2-C and TG were more pronounced in the middle-aged men then in the young men. After fasting overnight the effects of alcohol had disappeared.

Adult↗
PubMed1985

Protein composition of cyst fluids from mature teratoma in patients with nonseminomatous germ cell tumors of the testis.

Protein analyses were performed in 15 cyst fluids (CF) from mature teratoma (TD) and in 15 corresponding sera from 9 nonseminomatous germ cell tumor patients. Qualitatively, many similarities between the protein compositions of CF and corresponding sera were seen. Quantitative comparisons suggested free diffusion of plasma proteins into the cyst lumen in nine cases, whereas in five CF a decreased size selectivity of the blood-TD barrier was observed. From the quantitative data it was concluded that the significantly increased CCF/Cserum concentration ratios for the tumor markers alpha-fetoprotein (8/14), human chorionic gonadotropin (3/14), and carcinoembryonic antigen (13/13) as well as for lysozyme (12/13), ferritin (12/13), and fibronectin (3/6) were either due to local synthesis or to concentrating properties of the TD cells. The results of the current study encourage further research for new tumor-associated proteins in cyst fluids.

Blood Proteins↗
PubMed1982

Suppression of egg-laying during starvation in the snail Lymnaea stagnalis by inhibition of the ovulation hormone producing caudo-dorsal cells.

Starvation inhibits egg-laying in the snail, Lymnaea stagnalis. In starved animals the neurosecretory Caudo-Dorsal Cells (CDC), which produce the egg-laying hormone, are hyperpolarized as compared to the CDC of controls. However, they are more responsive to repetitive intracellular stimulation, which induces the hormone releasing discharge. Hyperpolarization is not found in the non-neurosecretory Cerebral Giant Cells, which indicates that the effect is specific for the CDC. It is also a characteristic effect of starvation as compared to another treatment (dirty water) inhibiting egg-laying.

Animals↗