Biomedical subjects

D Meister

Publications and source records attributed to D Meister.

16 recordsLinked to original sources

PubMed2002

Anti-inflammatory effects of enteral diet components on Crohn's disease-affected tissues in vitro.

BACKGROUND: The mechanism of action of elemental diet in Crohn's disease treatment, is unknown. Alteration of bacterial flora, low antigenicity, low fat content and improvement of nutritional status are postulated to play a role in the anti-inflammatory effect of elemental diet. AIM: To determine whether elemental diet or its modifications has a direct anti-inflammatory effect on colonic tissue biopsies in vitro. PATIENTS AND METHODS: Colonic or ileal biopsies from 39 patients with inflammatory bowel disease and control patients were incubated for 24 hours with enteral diets in which nitrogen sources were amino acids as in elemental diet, casein or whey. Tissues were incubated with elemental diet, casein or whey, at dilutions of 1:5, 1:10 or 1:20 in Waymouth's complete medium; a medium control was also included. Tissue viability was assessed by bromodeoxyuridine uptake. Interleukin-1beta, interleukin-1 receptor antagonist and interleukin-10 concentrations in supernatants were measured by immunoassay (enzyme-linked immunosorbent assay). RESULTS: Incubation of tissues from Crohn's disease with elemental diet resulted in an increase in the ratio of interleukin-1 receptor antagonist/interleukin-1beta vs control statistically significant at 1:10 (89.6+/-17 vs 45.7+/-9. 1, p<0.05). Incubation of Crohn's tissue with casein resulted in a significant increase of interleukin-1 receptor antagonist/interleukin-1beta ratio at dilutions 1:20, 1:10 and 1:5 (101.8+/-22.0, p=0.05, 142.8+/-24.6, p<0.05; 109.7+/-25.0, p=0.05). In ulcerative colitis tissue and non-inflamed non-inflammatory bowel disease control tissue, no significant increase in interleukin 1 receptor antagonist/interleukin-1beta ratio was seen after incubation with elemental diet, casein and whey. CONCLUSION: Elemental diet incubation increases anti-inflammatory:proinflammatory cytokine ratio in Crohn's disease and this anti-inflammatory effect is not specifically due to amino acid composition, as diets containing casein have similar anti-inflammatory effects.

Adolescent↗

PubMed2001

Modification of enteral diets in inflammatory bowel disease.

The provision of food is thought to promote the maintenance of gut integrity. Nutrients are able to elicit and affect both systemic and mucosal immune responses. Enteral diet therapy has long been known to be efficacious in inflammatory bowel disease (IBD), particularly in childhood Crohn's disease. However, the mechanisms of action of these diets are not clear. Nutritional repletion, direct effects on the gut mucosa or decreased intestinal permeability have all been postulated as being important in nutritional therapy. There is some evidence that the enteral diet has a direct effect on the gut mucosa by reducing cytokine production and the accompanying inflammation, thus leading to decreased intestinal permeability. Modifications of enteral diet composition have been evaluated in many studies. Such modifications include fat and/or protein content and the addition of bioactive peptides. The fatty acid composition of the enteral diet seems to have a much greater impact on its efficacy than modification of the N source. As specific fatty acids are precursors of inflammatory mediators derived from arachidonic acid, the reduction in these components may be beneficial in nutritional therapy for IBD. Addition of bioactive peptides to enteral diet formulas may also have a role; such peptides may have specific growth factor or anti-inflammatory actions. There is still much work to be done to define disease-specific enteral diet formulas that are effective as therapies for both Crohn's disease and ulcerative colitis.

Cell Membrane Permeability↗

PubMed2001

A 3D electrical impedance tomography (EIT) system for breast cancer detection.

A medical device which allows imaging of the distribution of conductivity in 3D in regions below the skin surface has been developed and tested. Its purpose is to enable early detection and preliminary diagnosis of breast tumours. Design of the measuring system and software are described. Results of clinical evaluation of the system are presented. EIT images of healthy and cancerous breasts are presented and discussed. The system is able to visualize various states of the breast and it may be possible to apply it to breast cancer detection.

Breast↗

PubMed1997

Body composition at the bedside.

OBJECTIVE: To evaluate the use of an inexpensive hand-held bioelectric impedance analysis machine which measures lean body mass, by technical comparisons against standard instruments and techniques (an in-house bioelectric impedance machine and dual energy X-ray absorptiometry), and by performing body composition analyses in groups of potentially malnourished patients. DESIGN: Prospective simultaneous comparison of measurements made by the hand-held and in-house bioelectric analysis machines and dual energy x-ray absorptiometry. SETTING: Medical Physics Department and Gastrointestinal Unit in a university teaching hospital. SUBJECTS/METHODS: One hundred and sixty subjects were recruited into the study. Data from 58 adolescent and 14 adult volunteers and from 42 adult patients were used for technical comparisons (n = 114). Body composition information was evaluated (n = 102) for 60 adult volunteers and 42 patients (17 with eating disorders, 7 with chronic alcoholic pancreatitis and 18 with inflammatory bowel disease). OUTCOME MEASURES: Estimation of bias, limits of agreement and correlations on data from the three machines. Relationships between percentage body mass as lean, absolute weights and body mass index, in the adult subjects. RESULTS: Both resistance and calculated impedance measured by the hand-held machine significantly correlated with the impedance measured by the in-house machine (r = 0.996; P < 0.0001). An estimation of the level of agreement in percentage lean measurement between dual energy x-ray absorptiometry and hand-held bioelectrical impedance analysis machine by the Bland and Altman method showed a bias of -0.07% and satisfactory limits of agreement from -7.97% to 7.76%. Body mass index was similar in the groups of healthy men and women, but proportion of weight as lean was significantly higher in men than women. In underweight patients with eating disorders, the ratio of lean to fat varied widely; in inflammatory bowel disease patients, proportions of lean and fat were similar to controls; however patients with alcoholic pancreatitis had values for body mass index similar to controls, but had significantly lower proportion of their body weight as lean (P < 0.05). CONCLUSION: In non-obese and thin adults, an accurate two-compartment (lean, fat) measurement of body composition can be made in 10 min by using an inexpensive, hand-held, bioelectric impedance analysis machine.

Absorptiometry, Photon↗

PubMed1995

Interobserver variability of sonographically determined second-trimester nuchal skinfold thickness measurements.

Twenty physicians experienced in fetal sonographic evaluation obtained fetal nuchal skinfold thickness measurements in each of five pregnant women between 16 and 18 weeks' gestation. A random effects analysis of variance model was used to explore the sources of variation in the set of measurements, to determine the interobserver variability of sonographically measured second-trimester nuchal skinfold thickness. It was possible to obtain 96 measurements. Four measurements (all in the same patient) were deemed unobtainable due to fetal position. All recorded measurements were between 1.7 and 4.5 mm. The means (and ranges) for the five patients were 2.7 (1.7-3.6), 2.9 (2.0-4.5), 2.7 (2.0-4.0), 3.3 (2.2-4.0), and 2.7 (1.8-4.0) mm. The standard deviation for interobserver variability, caused by the combined effect of physician and machine imprecision, was 0.56 mm and the overall coefficient of variation was 19.8%. Interpatient differences were statistically significant (p = 0.004). Interphysician differences were not (p = 0.11). We conclude that experienced physician sonographers using high-resolution ultrasound equipment are able to obtain second-trimester nuchal skinfold thickness measurements within 1.1 mm of the estimated true value with 95% probability.

Analysis of Variance↗

PubMed1993

[Experiences with long-term intravenous therapy using teflon catheters in 80 horses].

In a retrospective study the tolerance to Teflon coated catheters in long-term intravenous medication was evaluated in 80 horses. Catheters were inserted into the jugular vein and remained there for 3 to 30 days (average 8.6 days). Catheters were flushed using an heparinized solution after each medication administration. The site of catheter placement was evaluated daily for swelling, pain and venous distensibility respectively. Swelling at the site of insertion was noted in 10 horses, a small subcutaneous abscess formation was identified in one horse. Fourteen sonographic evaluations were performed on 10 horses, demonstrating perivascular changes in four. Thrombus formation did not occur. In all horses the catheter could be identified floating freely within the vascular lumen. Catheter failure occurred in nearly a third of all cases either as a result of mechanical failure or of pull-out by the horse. After removal of the catheter no adverse side effects attributable to the mode of medication were noted in any of the horses. In conclusion, intravenous medication using Teflon-coated catheters is a suitable alternative to other modes of administration.

Abscess↗

PubMed1992

Kinetics of hydroxyethyl starch in horses.

In a controlled study, the distribution and elimination kinetics of hydroxyethyl starch as well as clinically relevant parameters were determined in horses. The half-life of the first phase was 5.59 hours, that of the second phase 122.22 hours. During the first phase, hydroxyethyl starch persisted almost exclusively intravascularly. The results of this study are largely in agreement with those in human beings. Thus, routes of elimination, duration of plasma-expanding action, distribution volume and redistribution kinetics in horses and human beings are very similar. However, the elimination kinetics of the second phase and the behavior of serum amylase appear to be equine-specific. Coagulation is barley influenced by the administration of hydroxyethyl starch. The results of this study confirm that hydroxyethyl starch is very suitable for use as a plasma-expander in horses.

Amylases↗

PubMed1990

[Preliminary experiences with the treatment of shock in horses with a plasma expander from a starch base].

HAES Steril 10% is a colloidal plasma expander rarely used in veterinary medicine. In this study HAES was used in clinical cases for the treatment of shock and in a comparative hypervolemic hemodilution study (HAES versus lactated Ringer's solution) using two experimental horses. Injection of a HAES volume equivalent to 10% of estimated blood volume resulted in a highly significant drop in PCV and in a significant drop in total protein concentration. Half live of HAES was approximately two hours. No incompatibility reactions were observed. In man HAES improves microcirculation. Studies in progress may confirm a similar effect in the equine.

Animals↗

PubMed1990

[Experiences with the QBC-V hematology system at the veterinary hospitals of Zurich and Bern].

The QBC V hematology system was tested with respect to its application in veterinary medicine. PCV's and counts of total leukocytes, granulocytes, lympho/monocytes and platelets collected from 435 horses, dogs and cats were determined and compared with conventionally measured values. Precision and accuracy were found to be good for the majority of parameters. In the authors' opinion the QBC V hematology system is well suited for use in veterinary practice.

Animals↗

PubMed1986

Analytical profile of metaclazepam.

Physical and physicochemical properties of 7-bromo-5-(2'-chlorophenyl)-2, 3-dihydro-2-(methoxy-methyl)-1-methyl-1H-1,3-benzodiazepine (metaclazepam, Talis), a new anxiolytic 2-methoxymethyl-1,4-benzodiazepine derivative, are reported. Furthermore the analytical methods for quantitative determinations of metaclazepam are described.

Anti-Anxiety Agents↗

PubMed1977

The tubular loop fermentor: oxygen transfer, growth kinetics, and design.

Oxygen transfer measurements using a dynamic method and evaluated with an appropriate mathematical model have been made on a tubular loop bioreactor, Correlations of the type used in tank systmes are used to describe the influence of power and aeration rate on the mass transfer coefficient. Yeast cultures grown on hydrocarbon and glucose substrates show growth characteristics similar to conventional tank results. Model considerations for large-scale tubular fermentors allow for the prediction of the steady-state oxygen profiles and maximum reactor length. Combination with two-phases flow and oxygen transfer correlations yields a design procedure for commercial scale tubular loop fermentors.

Absorption↗

PubMed1967