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S L Jensen

Publications and source records attributed to S L Jensen.

At least 55 records · Page 3Linked to original sources
PubMed1994

[Attitude of the population to organ transplantation].

The attitude of the Danish population towards organ transplantation was examined by means of an interview study, executed by the Gallup Institute. From a sample population of 1391 persons above 18 years of age, 798 persons (70%) were interviewed, in the period April 24th to May 3rd 1992. When asked what they thought the general attitude toward transplantation was amongst the population, 65% answered "positive" or "very positive". The attitudes to three situations, namely to organ donation after the death of a parent, spouse or child was examined subsequently. Amongst those who had an opinion, 75% (72-76%) were positive and 25% (24-27%) were negative. The younger the interviewed person, the more positive the attitude. According to the Danish law the relatives can decide for or against organ donation if the deceased has not expressed her view on organ donation. In view of the general positive attitude of the population it is proposed that we introduce a system where every adult person is asked concerning his/her attitude, e.g. in connection with the yearly income tax form or renewal of the health insurance certificate.

Adult↗
PubMed1994

Effect of chemical composition of man-made vitreous fibers on the rate of dissolution in vitro at different pHs.

Measurements of rates of dissolution of typical insulation wool fibers (glasswool and basalt based stonewool) and an experimental fiber were made using a flow-through equipment. The liquids used were a modified Gamble's solution, adjusted to pH 4.8 and 7.7 +/- 0.2, respectively. The dissolution of SiO2 and CaO was determined over periods of up to three months. The rate of dissolution of stonewool fibers was lower than that of glasswool fibers at pH 7.7, whereas the opposite was true at pH 4.8. The stonewool fibers dissolve congruently, but glasswool fibers tend to dissolve with leaching. The rates of dissolution of fibers of different compositions, including insulation wool (glasswool, basalt-based stonewool, slagwool) and experimental fibers were screened using a stationary set-up. Both the chemical composition and pH influenced the rates of dissolution. At pH 7.7 alumina was a determining component and at pH 4.8 the content of SiO2 and CaO was determinant. One experimental fiber with a high content of alumina was an exception having a fairly high rate of dissolution both at pH 4.8 and 7.7.

Calcium Compounds↗
PubMed1993

[Experimental gastrointestinal motility].

Gastrointestinal motility is a major field of research today; however, despite there being a huge amount of available data in the literature, its exact role as a diagnostic tool has yet to be defined. The purpose of this paper is to describe some of the existing experimental models and methods for conducting motility studies.

Animals↗
PubMed1992

Effects of noradrenaline and galanin on duodenal motility in the isolated perfused porcine pancreatico-duodenal block.

The influence of neurotransmitters on gastrointestinal motility is different in different segments of the gastrointestinal tract. To clarify the regulation of duodenal motility, the aim of the present study was to investigate the effects of alpha-adrenoceptor agonism and blockade and of galanin on duodenal motility. The study was undertaken in the isolated perfused porcine pancreatico-duodenal block. The agents under investigation were administered arterially. Duodenal motility was measured by means of a low-compliance perfusion system using an intraluminal catheter. In addition the concentration of galanin was measured in the portal effluent. We found that spontaneous motility was abolished by noradrenaline by an effect that was counteracted by the alpha 2-adrenoceptor antagonist idazoxan. In contrast, the selective alpha 1-adrenoceptor antagonist prazosin did not influence the effect of noradrenaline. Galanin, like noradrenaline, abolished duodenal motility. Furthermore, the concentration of galanin in the portal effluent was decreased by noradrenaline by an alpha 2-adrenoceptor mediated mechanism. We conclude that alpha 2-adrenoceptor activation and galanin inhibit duodenal motility and that the release of galanin from the pancreatico-duodenal preparation is reduced by alpha 2-adrenoceptors.

Adrenergic alpha-Antagonists↗
PubMed1992

Characteristics of spontaneous and evoked motility in the isolated perfused porcine duodenum.

The aims of the study were to evaluate characteristics of spontaneous motility and of the ascending excitatory peristaltic reflex (AEPR) and intraluminal cross-sectional area in the isolated perfused porcine duodenum. The parameters were measured by an intraluminal catheter by use of the perfused side-hole technique and impedance planimetry. Respiratory parameters such as pH and oxygen consumption and the arterial perfusion pressure were monitored and did not vary significantly throughout the study time. Spontaneous motility was intense at the beginning but declined and disappeared within 45-90 min. It was abolished by atropine, epinephrine, and UK-14,304 (an alpha 2-adrenoceptor agonist). Secondary motility was evoked by intraluminal balloon distensions by raising the balloon pressure to 1.5 kPa for 1-min periods. Reproducible results regarding the AEPR, external balloon diameters to elicit the AEPR, and intraluminal cross-sectional area were obtained. The order of potency (pD2 values) for inhibition of the AEPR was the selective M3-receptor antagonist 4-DAMP greater than atropine greater than the selective M2-receptor antagonist AFDX-116 greater than the selective M1-receptor antagonist pirenzepine greater than hexamethonium. 4-DAMP was 16 and 29 times more potent than AFDX-116 (P less than 0.02) and pirenzepine (P less than 0.02). None of the drugs altered the intraluminal cross-sectional area during the balloon distensions. The model provides the opportunity for physiological and pharmacological studies of duodenal motility and duodenal cross-sectional area devoid of extrinsic neural and endocrine effects. The abolishment of the AEPR by atropine is caused by blockade of the M3-receptor in the porcine duodenum.

Animals↗
PubMed1992

Role of sucralfate in peptic disease.

Sucralfate, a basic aluminum salt of sucrose, was the first successful drug with a major cytoprotective mechanism of action. It binds bile acids and pepsin and adheres to both ulcerated and nonulcerated mucosa. Sucralfate stimulates the synthesis and release of gastric mucosal prostaglandins as well as bicarbonate and the epidermal growth factor which stimulates healing. Sucralfate is the safest drug available today in the treatment of dyspeptic symptoms and compared to ranitidine and cimetidine it has the following characteristics. (2) The short-term healing of duodenal ulcers is the same for sucralfate, cimetidine and ranitidine. (3) Sucralfate-treated patients have a lower recurrence rate of duodenal ulceration after healing when compared with cimetidine and the recurrence rate is not connected with the presence or absence of Campylobacter pylori.

Cimetidine↗
PubMed1992

Galanin inhibits tolbutamide-stimulated insulin secretion in the perfused pig pancreas.

The neuropeptide galanin is known to inhibit insulin secretion in a variety of species. However, controversies exist regarding its action on insulin secretion in the perfused pig pancreas, since both inhibitory and stimulatory effects have been described. We therefore perfused the isolated porcine pancreatico-duodenal block with galanin (100 nmol/l) in the presence of 5 or 15 mmol/l glucose or with 5 mmol/l glucose and 10 mumol/l tolbutamide. We found that at this dose level, galanin did not affect insulin secretion stimulated by glucose alone. In contrast, galanin clearly suppressed tolbutamide-stimulated insulin secretion. Hence, we conclude that galanin has a weak influence on insulin secretion in the pig pancreas, being unable to inhibit glucose-stimulated insulin secretion at the dose level of 100 nmol/l. However, when active, galanin clearly inhibits insulin secretion also in the pig pancreas.

Animals↗
PubMed1991

[Laparoscopic cholecystectomy. The first 45 operations].

During a period of 13 weeks, 45 patients with symptom-producing gall bladder stones (attacks of gall stone colic n = 39 (87%); acute cholecystitis n = 6 (13%)), corresponding to approximately 85% of the total number of gall bladder stone patients during the period were selected for laparoscopic cholecystectomy. Two patients had previously undergone upper abdominal operations and had adhesions and one patient suffered from cirrhosis of the liver with portal hypertension. It proved necessary to convert five of the laparoscopic cholecystectomies to open cholecystectomies (11%) on account of technical difficulties (severe acute changes due to cholecystitis (n = 3), indeterminable anatomical conditions (n = 1) and one case of liver metastases (n = 1)). The median duration of operation was 90 minutes with a range from 30 to 360 minutes. Peroperative cholangiography was not undertaken routinely. No cases of forgotten stones in the common bile duct occurred. No deaths occurred and, in all, three slight complications occurred (7%): two patients had haematoma in the abdominal wall and one patient minimal leakage of bile from the stump of the gall bladder on account of insufficient ligation of the cystic duct. This patient was treated with an endoscopically placed drain in the common bile duct for two weeks, after which she was well. No lesions of the common bile duct occurred. None of the complications required laparotomy. The median duration of hospitalization was 24 hours with a range from one to 14 days. All of the patients were at work or could manage their usual activities after 14 days. The median duration of sick leave was seven days.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

An alpha 1-adrenoceptor-sensitive mechanism is responsible for the adrenergic inhibition of insulin secretion in the pig pancreas.

The alpha-adrenoceptor subtype mediating inhibition of insulin secretion in the pig was examined in an isolated pancreas preparation perfused with 5 mM glucose. It was found that noradrenaline and the alpha 1-adrenoceptor agonist phenylephrine, but not the alpha 2-adrenoceptor agonist UK 14,304, inhibited insulin secretion. The effect of noradrenaline was abolished by the alpha 1-adrenoceptor antagonist prazosin but was not affected by the alpha 2-adrenoceptor antagonist idazoxan. The inhibitory effect of phenylephrine was also inhibited by prazosin. Thus, in the pig, the alpha-adrenoceptor subtype inhibiting insulin secretion is of the alpha 1-type, which is different from the subtype involved in other species.

Adrenergic alpha-Agonists↗
PubMed1991

Distribution and effect of galanin on gallbladder and sphincter of Oddi motility in the pig.

This study was designed to determine the occurrence and topographical distribution of galanin-like immunoreactivity (GAL-LI) in the porcine gallbladder and sphincter of Oddi and to investigate the pharmacologic effect of GAL on gallbladder and sphincter of Oddi motility. By radioimmunoassay the concentration of GAL-LI in the gallbladder was 2.75 +/- 0.23, 9.73 +/- 1.33 in the common bile duct and 5.10 +/- 0.37 in the sphincter of Oddi (pmol/g +/- SE). By immunohistochemistry GAL-LI was found exclusively in ganglionic cells and in nerve fibers among the smooth muscle bundles. Gallbladder and sphincter of Oddi pressures were recorded before and during 5-minute local intraarterial infusion of 4, 8, 19, 39, 78 and 194 ng GAL - Kg-1 - min-1 in 12 anaesthetized pigs. GAL in doses greater than or equal to 39 ng.kg-1.min-1 significantly reduced sphincter of Oddi phasic wave frequency (4.8 +/- 0.4 vs. 2.1 +/- 0.5; p = 0.004) and sphincter of Oddi motility index (70.2 +/- 6.02 vs. 27.7 +/- 8.3; p = 0.002) but did not affect gallbladder pressure. We conclude that the distribution of GAL-LI in the sphincter of Oddi and the effect that a pharmacologic dose of GAL has on sphincter of Oddi motor activity, suggests that GAL may be involved in the physiologic control of bile flow in the pig.

Animals↗
PubMed1991

Experimental gastrointestinal motility: where to go.

Gastrointestinal motility is a major field of research. However, despite a huge amount of data available in the literature, its exact role has yet to be defined. This paper deals with the choice of animal research models for motility studies.

Animals↗
PubMed1991

Effects of pirenzepine and atropine on basal lower esophageal pressure and gastric acid secretion in man: a placebo-controlled randomized study.

Pirenzepine is a tricyclic antimuscarine drug with antisecretory effect on gastric secretion and inhibitory effect on esophageal peristalsis (EP). The effect of pirenzepine in graded doses on basal and pentagastrin-stimulated lower esophageal sphincter pressure (LESP) was studied in 8 volunteers. The effect was compared with the effect of atropine and placebo using a double dummy technique. Intravenously administered pirenzepine and atropine inhibited basal LESP and EP regardless of the employed doses. No difference between atropine and pirenzepine could be demonstrated. The pentagastrin-stimulated LESP was inhibited in patients treated with pirenzepine perorally (50 mg b.i.d.). Basic acid output was significantly reduced by pirenzepine or atropine in contrast to peak acid output. We conclude that muscarinic receptors of type M play a role in the LES function in man.

Atropine↗
PubMed1991

Effect of vasoactive intestinal peptide on duodenal motility in the isolated perfused porcine pancreaticoduodenal block.

The peptidergic regulation of duodenal motility has not been clarified in detail. The aim of the present study was to investigate the effect of vasoactive intestinal polypeptide (VIP) on duodenal motility in the isolated perfused porcine pancreaticoduodenal block. VIP was administered arterially at 10(-7) M and motility was measured by means of the perfused side-hole technique using an intraluminal catheter. It was found that spontaneous duodenal motility was intense at the beginning of each experiment. However, the spontaneous motility diminished by time to cease after 45-90 min. VIP inhibited the duodenal motility. Thus, the frequency of duodenal contraction was decreased from 11 (8-16) to 3 (0-10) contractions per minute by VIP (p less than 0.01) and VIP also decreased the arterial perfusion pressure from 7.5 (3.5-23.2) to 5.8 (2.6-17.3) kPa (p less than 0.01). Since the same inhibitory effect has previously been demonstrated after alpha 2-adrenoceptor activation, we also examined whether alpha 1- and alpha 2-adrenoceptor agonism stimulated the release of VIP from this preparation. We then found that alpha 1-adrenoceptor agonism (phenylephrine or noradrenaline plus idazoxan) given intra-arterially stimulated VIP release (p less than 0.01). In contrast, alpha 2-adrenoceptor agonism (UK-14,304 or noradrenaline plus prazosin) had no effect. Therefore, we conclude that VIP inhibits duodenal motility in the pig but that this effect does not mediate the sympathetically induced inhibition of motility.

Animals↗
PubMed1991

Elastic properties of the isolated perfused porcine duodenum.

The aim was to investigate elastic wall properties of the isolated perfused porcine duodenum using manometry and impedance planimetry. Distension of an intraluminal balloon with definite pressure steps of 0.5, 1.0, 2.0, 3.0 and 5.0 kPa was done with simultaneous recording of balloon pressure and balloon cross-sectional area (Bcsa). Wall thickness of the relaxed intestine was estimated from measurement of tissue density. The elastic wall parameters were calculated from these measurements. Balloon inflation elicited a phase of rapid Bcsa increase followed by an accommodation phase of slow Bcsa increase. At steady state, the circumferential and the radial wall stress increased as linear functions of the applied balloon pressure, while the circumferential and the radial wall strain increased nonlinearly. The incremental elastic moduli increased exponentially. Our model allows the study of passive biomechanical wall properties of the intact duodenum. The duodenal wall showed qualitatively and also quantitatively an elastic nature.

Animals↗