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Biomedical subjects

C Winckler

Publications and source records attributed to C Winckler.

At least 19 recordsLinked to original sources
PubMed2004

Studies on the time course of the effects of the probiotic yeast Saccharomyces boulardii on electrolyte transport in pig jejunum.

Orally administered Saccharomyces boulardii (synonym Saccharomyces cerevisiae Hansen CBS 5926) has already been shown to affect relevant functions of the mucosa in pig jejunum such as lowering the secretory response to theophylline or stimulating sodium/glucose cotransport, but knowledge of time-dependent relationship is minimal. In this study we examined the effects of S. boulardii on sodium (Na+) and chloride (Cl-) transport in pig jejunum under nonstimulated (basal) and stimulated (secretory) conditions. For this purpose the conventional Ussing chamber method was used for measuring electrical parameters (short circuit currents, Isc; tissue conductances, G(T)) and electrolyte transport of isolated intact jejunal epithelia in the absence and presence of the secretagogue theophylline (10 mM, serosal side). Time profiles of the mucosa response were assessed by treating animals perorally with S. boulardii for 0 (control), 3, 8, and 16 days. Intestinal tissues were obtained from growing pigs in the weight range between 25 and 40 kg. All animals were fed twice daily and received 1.0-1.6 kg/day of a standard diet avoiding probiotics as food additives. After a 9- to 10-day adaptation period the diets for treated animals were supplemented with approximately 1.8 x 10(7) colony forming units (CFU)/g feed of the probiotic. Whereas basal tissue conductances were not affected by treatment duration, basal Isc values decreased significantly during 8 days of treatment, by 26%, indicating a lower electrogenic net ion transport, which, however, was reconstituted after 16 days. This effect could be explained by almost the same reduction of basal Jms of Na+ during 8 days of treatment, whereas respective flux rates in the opposite direction remained stable. Under basal conditions unidirectional and net flux rates of Cl- were not affected by S. boulardii. Induction of secretory conditions by theophylline revealed pronounced increases in net Cl- secretion but this effect was more than 60% lower after 8-day S. boulardii application, and this was reflected by a respectively lower Isc stimulation. Interestingly, this inhibitory effect on the secretory response could no longer be observed in the 16-day group. And this was reflected by a respectively lower Isc stimulation. A similar effect could be observed regarding net Na+ flux rates. Residual fluxes were affected neither by S. boulardii nor by theophylline, therefore, Isc values can be explained completely by respective Na+ and Cl- fluxes. In conclusion, S. boulardii has specific duration-dependent effects on the secretory response of the pig jejunal mucosa which developed during 8-day treatment but disappeared during further application. Thus, this study supports the concept that probiotics may exert beneficial effects in the gastrointestinal tract.

Animals↗
PubMed2002

Research note: Postnatal development of electrolyte transport in calf rumen as affected by weaning time.

In a previous study we found a positive correlation between early weaning in calves and morphological parameters which were indicative of ruminal development, i.e. the length and width of the papillae. The objective of the present study was to determine to what extent this observation could be reflected by modulations of absorptive and secretory functions of the rumen mucosa. For this purpose the short-circuit currents (Isc) as a measure of electrogenic net ion fluxes and the transepithelial conductances (G(T)) as a measure of the overall tissue permeability were measured in vitro applying the Ussing-chamber technique. Simultaneously, the unidirectional flux rates of sodium and chloride across rumen wall epithelia were determined in the absence of electrochemical gradients. Under these conditions, significant positive net flux rates (Jnet) clearly indicate active mechanisms for electrolyte absorption. For the experiments 12 male Holstein calves 7 d of age were assigned to three groups of 4 animals each: milk group (I, slaughtered after 6 weeks of age), late weaning group (II, slaughtered after 9 weeks of age) and early weaning group (II, weaned after 6 weeks of age and slaughtered after 9 weeks of age). Whereas G(T) values remained unaffected by different age and feeding, Isc values were significantly affected by early weaning but were not influenced by age. Irrespective of weaning time active absorption of Na+ tended to be higher by about 60% in 9 weeks old animals. Active absorption of chloride was significantly increased in milk fed 9 weeke old calves and this effect was further stimulated by early weaning. In conclusion, the data show an increasing active Na+ absorption with age in calf rumen that could not be influenced by early weaning. Similarly, active Cl- absorption was initially increased during postnatal development and this effect could be stimulated further by early weaning.

Absorption↗
PubMed2001

Colonic fermentation as affected by antibiotics and acidic pH: Application of an in vitro model.

Antimicrobial substances such as vancomycin or metronidazole suppress normal gut flora, thereby preventing physiological fermentation of colonic substrates that may promote mucosal inflammation. This study was designed to establish an in vitro model of microbial metabolism in the colon under control and disturbed conditions (acidic pH) to investigate specific effects of vancomycin and metronidazole on the production of short chain fatty acids (SCFA), which play a pivotal role in maintaining homeostasis in the colon. The experiments were carried out with the colon simulation technique (Cositec) representing an in vitro model for the semi-continuous incubation of defined colon contents. Inocula and fermentable substrates were sampled from cecal contents of fistulated pigs. Disturbed microbial metabolism was generated by reduction of pH in the fermentation vessels from 6.7 to 5.8 and 5.1. In general, application of either vancomycin or metronidazole resulted in a significant decrease of SCFA production rates indicating substantial disturbance of the homeostasis of microbial metabolism. With low doses of vancomycin acetate and butyrate production rates were reduced and with high doses of the antibiotic propionate production was inhibited to a greater extent. Treatment with metronidazole inhibited butyrate production almost completely. Similarly, low pH caused a reduction in total SCFA production, which was mainly due to respective decrease of acetate synthesis. Metronidazole effects were not consistently changed at low pH. The Cositec system provides an excellent facility to test the effects of different antibiotics under defined conditions. In this study, both vancomycin and metronidazole affected microbial metabolism to a considerable extent. Both substances may thus be responsible for disturbances of colon function in vivo.

Acid-Base Equilibrium↗
PubMed1999

Characteristics of dipeptide transport in pig jejunum in vitro.

Characteristics of dipeptide transport in pig jejunum were investigated in vitro by applying the Ussing-chamber technique and mucosal uptake studies. Addition of both glycyl-L-glutamine and glycyl-L-sarcosine (20 mmol.l-1) to the mucosal buffer solution significantly increased the short-circuit current by 2.60 +/- 0.15 and 1.57 +/- 0.20 mu eq.cm-2.h-1, respectively. Concentration-dependent changes in short-circuit current followed Michaelis-Menten kinetics with similar affinity constants for both dipeptides. From unidirectional flux rates for radiolabelled glycyl-L-sarcosine, a net flux rate for glycyl-L-sarcosine of 49.8 +/- 6.7 nmol.cm-2.h-1 was calculated. In mucosal uptake experiments, the apical influx of 14C-labelled glycyl-L-sarcosine into isolated porcine mucosa was pH dependent and significantly inhibited by glycyl-L-glutamine. Moreover, RT-PCR studies with primers derived from rabbit PepT1 identified two PCR fragments of identical size to rabbit PepT1 from pig intestinal mRNA preparations. In conclusion, our studies revealed key features of mammalian intestinal peptide transporters and give evidence for a PepT1-like transporter in the pig jejunum that could significantly contribute to the overall amino acid absorption from the gut.

Animals↗
PubMed1999

Morphological and functional development of the rumen in the calf: influence of the time of weaning. 1. Morphological development of rumen mucosa.

The objective of this study was to determine whether the nutritional regimen of rearing calves would influence the morphometric and histological development of rumen mucosa. Twelve male Holstein calves 7 d of age were assigned to three groups of 4 animals each: milk group (I), early weaned (6 weeks) group (II) and late weaned (9 weeks) group (III). All animals received additional solid feed. Animals of group I were slaughtered after 6 weeks of age, whereas those in groups II and III were slaughtered after 9 weeks of age. At slaughter, the ruminal digesta amounted to 2035 g (milk group), 3092 g (late weaned group) and 5374 g (early weaned group). The differences in the ruminal molar percentage of SCFA were not significant. There was a trend for lower pH and higher SCFA concentrations in the order late weaned, early weaned and milk fed animals (pH: 6.4, 6.6 and 6.7, respectively; SCFA: 96, 87 and 77 mmol/l, respectively). The mean length (1.07 mm in milk group, 1.45 mm in late weaned group and 1.87 mm in early weaned group), width (0.43, 0.58 and 0.71 mm, respectively) and surface of papillae (190, 232 and 241 mm2/cm2 mucosa, respectively) increased with both the age of the animals and the elevated intake of solid feed, whereas the number of papillae (210, 140 and 92 per cm2 mucosa, respectively) decreased. In both milk-fed groups type A and B corneal cells were present in the Stratum corneum, whereas in the earlier weaned calves type C-cells could be also seen. These findings indicate a more advanced stage of development of the rumen epithelium in the earlier weaned calves fed higher amounts of concentrate and hay.

Animal Feed↗
PubMed1997

[Suffering and misfortune--the beginning of comprehension].

Pain, suffering and damage are important items of the animal protection law and thus the basis for its accomplishment. It is the aim of this paper to give a review on those methods which are available to record and to assess well-being or suffering of animals. Since suffering cannot be measured directly different indicators such as health, productivity, physiological and biochemical parameters and behaviour have to be used in order to obtain conclusive evidence of suffering or well-being. Since it has to be taken into account that the individual indicators are of limited value with respect to their reliability and accuracy the combination of these indicators has to be recommended.

Animal Welfare↗
PubMed1996

[A survey of the diffusion and impact of consensus development conference on infections caused by central venous catheters in an anesthesiologist team].

OBJECTIVES: To assess the diffusion and the impact on the professional practices of a consensus conference (CC) by the French speaking Society of Intensive Care on "Central venous catheter-related sepsis in intensive care". STUDY DESIGN: Before-after survey with two successive questionnaires. MATERIAL AND METHODS: Two questionnaires (Q1 and Q2) were circulated either to intensivists (group 1) or to anaesthetists (group 2) of a University Hospital, before (Q1) and after (Q2) distribution of the CC conclusions. They aimed to assess the diffusion of the conclusions by the CC; the professional practices before the CC and their modifications after consideration of the recommendations by the CC. RESULTS: Out of the 55 consulted, 85% answered Q1, and 71% Q2. Among them, 42% were aware of the conclusions of the CC before starting the survey-73.5% from group 1 and 28% from group 2. Therefore, conversely to anaesthetists, intensivists, did not significantly modify their professional practices after consideration of the CC conclusions. CONCLUSION: This study shows a satisfactory diffusion of the content of jury's recommendations among anesthetists whereas the impact was less satisfactory with intensivists. The impact of a CC could probably be improved by a better diffusion of the consensus statements and by the intervention of local linkmen.

Anesthesiology↗
PubMed1996

[Prospects and limits of animal breeding from the physiological aspects].

Livestock breeding is characterized by substantial increases in performance in recent years. However, pathophysiological changes have to be considered when increased production levels will exceed maximal physiological capacities. Gastrointestinal adaptation processes of ruminants kept under aride grazing conditions are discussed in comparison with european sheep breeds. The high stress susceptibility in pigs which is genetically determined is taken as a further example to explain the onset of diseases on the basis of pathophysiological mechanisms being induced by breeding techniques. From this the necessity for a close cooperation between animal breeding and physiology has to be concluded.

Animal Husbandry↗
PubMed1994

[Rupture of the left bronchus during intubation by Carlens tube].

The authors report a case of left main bronchus rupture following endotracheal intubation with a Carlens double-lumen tube. The bronchus rupture occurred during a cure of gastro-oesophageal-reflux and resection of oesophageal diverticula through a left thoracotomy. The patient was a 65-year-old woman treated with corticosteroids for an Addison's disease. The weakness of the bronchial wall initiated by the steroid hormones was an important factor contributing to the perforation. There is also a higher risk of rupture during oesophageal surgery because of surgical dissection and stretch on the tracheobronchial airway. This case demonstrates that such a complication can occur without ventilatory failure. A rupture must be recognized and treated surgically very rapidly. Recommendations regarding the use of double-lumen endotracheal tubes are reviewed in order to decrease the occurrence of such a complication.

Addison Disease↗
PubMed1993

Metabolic effects of propofol and flunitrazepam given for sedation after aortic surgery.

Sixteen patients who had undergone abdominal aortic surgery were allocated randomly to receive either propofol (total dose 3.2 (SEM 0.3) mg kg-1 h-1) or flunitrazepam (total dose 15 (2) micrograms kg-1 h-1) for 16 h after operation. Metabolic effects of sedation were assessed using a Deltatrac metabolic monitor. Initiation of sedation induced a 25% decrease in VO2 in both groups. The decrease was about 40% at 16 h. VO2 increased within 30 min after discontinuation of propofol and stabilized at values considerably less than the immediate postoperative value. A similar but slower increase was noted with flunitrazepam. While the propofol loading dose reduced the Buffington index and should therefore be avoided, no cardiovascular side effects were noted with the maintenance infusion. Weaning from ventilatory support was achieved within 15 (2) min and 264 (108) min after discontinuation of propofol and flunitrazepam, respectively.

Aortic Aneurysm, Abdominal↗
PubMed1991

[Celiac plexus block: value of x-ray computed guidance].

Celiac plexus block is a good alternative of pain treatment in upper abdominal pain. Neurolysis of the celiac plexus by the percutaneous posterior route used CT guidance in 8 patients. Pain relief was obtained in 5 of 7 patients (70 per cent); no complication occurred.

Abdominal Pain↗