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Biomedical subjects

G Müller

Publications and source records attributed to G Müller.

At least 19 recordsLinked to original sources
PubMed2007

Critical evaluation of methods for determination of body fat content in children: back to basic parameters?

Considering the increasing prevalence of obesity among children and of obesity related disorders in the pediatric population, the reliable evaluation of body fat content in children is of critical importance in research and clinical medicine. In this study, we assessed the congruency of different estimates for body fat content in prepubertal children. We determined anthropometric parameters, such as BMI and skinfold thickness, and bioelectrical impedance in 676 prepubertal Caucasian children. We calculated body fat percentage (BF%) from these parameters applying 5 distinct algorithms and established raw centiles for these models. Expectedly, girls had significantly higher BF% regardless of the method applied. There were, however, significant variances in the calculated amount of BF% between the algorithms, with BIA based equations giving highest BF%, while skinfold based equations tended to provide lower BF% values. Direct comparison of the algorithms revealed a high degree of inconsistency and poor agreement in the assessment of body fat with variations of >10% BF%. Great differences in basic parameters, such as DeltaBMI (3.2 kg/m (2)) or Deltaskinfolds (1.75-fold), would be needed to reliably predict correct ranking of 10% difference in body fat with 95% probability. In summary, BF% strongly varies depending on both the method as well as the algorithm used. This questions the applicability of such field methods for the assessment of BF% for comparative analyses and the superiority of information over basic parameters such as BMI.

Adipose Tissue↗
PubMed2006

["Fatigue" in multiple sclerosis. Development and and validation of the "Würzburger Fatigue Inventory for MS"].

BACKGROUND: Fatigue is one of the most common, yet poorly defined, disabling symptoms in patients with multiple sclerosis (MS). Several fatigue scales have been developed, but rigorous psychometric methods have not always been applied and validation was mainly based on small numbers of patients. We therefore assembled a new fatigue scale from a set of widely used scales and assessed its psychometric properties in a large sample of MS patients. PATIENTS AND METHODS: Fatigue was assessed in 158 MS patients by four published quantitative scales: the Fatigue Severity Scale (FSS), Modified Fatigue Impact Scale (MFIS), MS-specific Fatigue Severity Scale (MFSS), and Visual Analogue Scale. From these a new fatigue scale, the Würzburg Fatigue Inventory for Multiple Sclerosis (WEIMuS), was assembled. It contains 17 items with values from 0 to 4. The WEIMuS scale was validated in a subgroup of 67 patients and a control group of 68 patients. RESULTS: The MFIS and FSS but not the MFSS showed high internal consistency and split-half reliability. After applying factor analysis within the scales, fairly reliable and valid items originally found in the MFIS and FSS were selected to construct the final 17-item WEIMuS scale, which showed a high degree of reliability. In the validation study, varimax rotated factor analysis extracted two main factors corresponding to both cognitive and physical fatigue. CONCLUSION: The new, two-dimensional WEIMuS showed good psychometric properties, is easy to use, and may therefore be a useful tool for the assessment of MS-associated fatigue. Multiple sclerosis patients suffer from different types of fatigue which could be attributed to cognitive and physical fatigue. Thus, MS-associated fatigue is different from common tiredness.

Adult↗
PubMed2006

Comparative study of in vitro cytotoxicity of povidone-iodine in solution, in ointment or in a liposomal formulation (Repithel) and selected antiseptics.

The cytotoxicity of povidone-iodine in Repithel, Betaisodona ointment and Betaisodona solution was investigated using CHO-K1 cells. To estimate the vitality of test cells after 30 min contact time using vital dye neutral red, the following IC(50) were determined: 16-18% Repithel, 8-9% Betaisodona ointment and 1.8-2% Betaisodona solution; using MTT for detecting vitality, the IC(50) were: 5-10% Repithel, 1.3-2.5% Betaisodona ointment and 0.6-1.3% Betaisodona solution. Therefore, the first attack of the antiseptic agent iodine to mammalian cells is carried out on enzymes, perhaps by oxidation, followed by membrane attack. Murine fibroblasts were used to compare the cytotoxic impact of povidone-iodine with those of chlorhexidine digluconate (CHex), octenidine dihydrochloride (Oct) and polyhexamethylene biguanide (PHMB). On the base of molecular concentration, povidone-iodine is more than 20 times better tolerated by L929 cells than CHex, Oct or PHMB. Moreover, after 30 min contact of L929 cells with povidone-iodine, there is a temporarily cytotoxic reaction, which leads after 24 h culture to an unexpected revitalisation of murine fibroblasts. This phenomenon was not detected using CHex, Oct or PHMB. Povidone-iodine seems to be the most tolerated antiseptic in comparison with CHex, Oct or PHMB.

Administration, Topical↗
PubMed2006

Lack of in vitro genotoxicity of povidone-iodine in solution, in ointment or in a liposomal formulation (Repithel).

The in vitro genotoxicity of povidone-iodine in Repithel, Betaisodona ointment and Betaisodona solution was investigated using CHO-K1 cells. The comet assay and chromosome aberration test were used to characterise the genotoxic potency of povidone-iodine within 4 h of contact with test cells. Methyl methanesulphonate without S9 activation and benzo[a]pyrene with S9 activation were used as positive controls. No higher concentrations than 6% Repithel, 5% Betaisodona ointment and 2% Betaisodona solution in culture medium with 10% fetal bovine serum were tested within 4 h of contact with CHO-K1 cells for the comet assay, because higher concentrations will provide >60% cytotoxicity. All tested concentrations of povidone-iodine formulations (4-6% Repithel, 3-5% Betaisodona ointment and 1-2% Betaisodona solution) are not genotoxic in the comet assay. 10% Repithel, 5% Betaisodona ointment and 2.5% Betaisodona solution in culture medium with 10% fetal bovine serum were final concentrations in the chromosome aberration test, which provide <60% cytotoxicity within 4 h of contact with CHO-K1 cells. All tested concentrations of povidone- iodine formulations (5-10% Repithel, 2.5-5% Betaisodona ointment and 1.25-2.5% Betaisodona solution) are not genotoxic in the chromosome aberration test. Using the comet assay and chromosome aberration test to characterise the genotoxic potency of povidone-iodine within 4 h of contact with CHO-K1 cells, there was no chromosome damage detected.

Animals↗
PubMed2006

New molecular data on mammalian Hepatozoon species (Apicomplexa: Adeleorina) from Brazil and Spain.

Molecular techniques were used to examine the phylogenetic relationships among Hepatozoon species isolated from 13 foxes and 15 opossums from Brazil, and from 15 dogs, 20 foxes, 45 rodents, and 330 domestic cats from Spain. Hemogregarine infection was confirmed by amplification of the 18S rRNA gene and later sequencing. No hemogregarine infections were found in opossums. The prevalence of Hepatozoon in canids ranged from 26.6% (symptomatic domestic dogs) to 90% (Spanish foxes). Four different H. canis genotypes were detected, as well as an H. americanum-related protozoan (97% identical to the USA strain). Two Spanish cats were parasitized by a Hepatozoon species (0.6% prevalence) that showed 96% sequence identity to H. canis. DNA amplification assays performed on Spanish rodents showed 2 bank voles (Clethrionomys glareolus) to be infected by a Hepatozoon species (4.44% prevalence) with 95% sequence identity to Hepatozoon sp. from cats. Phylogenetic analysis showed Hepatozoon to be a monophyletic genus, in which species from carnivorous mammals (Hepatozoon sp. from cats, H. americanum and H. canis) appear as a sister lineage of that of lower vertebrates and rodents. This association suggests that H. americanum evolved in ticks and carnivores (either canids, or felids, or both) rather than in other ectoparasites and other types of mammal.

Animals↗
PubMed2006

The classification of antiseptic products to be administered to wounds--another borderline case between medicinal products and medical devices?

The importance of a correct demarcation between a Medicinal Product (MP) and a Medical Device (MD) is undisputedly one of the major topics related to the development and launch of a new healthcare product. However, for some products the correct demarcation between MPs and MDs can turn out to be somewhat complicated. This article aims to provide an overview on the existing legislation and its adequate application based on a suitable example at hand. Article 2 (2) of the European Directive 2001/83/EC as amended by Directive 2004/27/EC on the Community code relating to medicinal products for human use stipulates that the respective Medicinal Products Legislation must be applied whenever a product can be covered by both the definitions for MPs and for products regulated by other legal provisions enacted by the European Community, e.g. Cosmetic Products (CPs) or MDs. This basic principle implies that the decision to base the risk-benefit assessment of the product in question on the Medical Device Directive (MDD) would contradict the aforementioned constitutional principle, pursuant to which the stricter of the regulatory procedures theoretically possible is to apply in cases of doubt. In contrast to the approval procedure established for MPs, the MDD requires a Conformity Assessment Procedure to be performed by the manufacturer himself and a "Notified Body". Thus, in the majority of cases the responsibility for the risk assessment of MDs lies solely with the manufacturer and is prior to launch not subject to further scrutiny by regulators. Only in specific cases, i.e. for the Conformity Assessment Procedure of Class III MDs which contain an Active Pharmaceutical Ingredient one of the Member States competent authorities designated in accordance with Directive 65/ 65/EEC has to be involved before taking a decision. It is therefore important that the classification of the product is carried out carefully in full compliance with existing legal provisions, also taking into account the related guidance documents issued by the European Commission. The adequate application of these rules is explained using the example of the antiseptic compound polihexanide, which is used both in approved medicinal products (wound antiseptics) and wound irrigation solutions labelled as medical devices.

Animals↗
PubMed2005

[Mysterious lower gastrointestinal bleeding in diverticular disease of the colon].

HISTORY AND ADMISSION FINDINGS: Within a few weeks a 78-year-old woman presented three times in hospital with dramatic blood loss in need of transfusion. At her admission to hospital she complained about general weakness and painless melena. Within the last few years the patient had been treated with aspirin and phenprocoumon for chronic atrial fibrillation and coronary heart disease. INVESTIGATIONS: Laboratory findings revealed a very low hemoglobin of 6 g/dl when the patient presented at hospital. The esophagogastroduodenoscopy was normal. The first colonoscopy detected diverticula of the left colon and fresh blood in the whole colon. The definitive bleeding site could not be identified. A technetium-colloid scan revealed an increased blood loss in the right colon. A second colonoscopy performed at the same time confirmed a right sided bleeding and an active capillary bleeding in the coecum without any mucosal lesion was identified. DIAGNOSIS, TREATMENT AND COURSE: As during the patient's first stay at hospital the site of lower gastrointestinal bleeding could not be determined, the patient was treated by transfusion and oral anticoagulation was stopped. The bleeding stopped spontaneously within a few days. At the third rebleeding episode examinations located the bleeding in the right colon, and a right hemicolectomy was performed. After the operation a piece of chicken bone was detected in the wall of the coecum, which had led to a chronic mucosal bleeding after penetration of the colonic wall. After surgery the patient recovered quickly and no rebleeding recurred. CONCLUSION: Identification of the exact origin of lower gastrointestinal tract bleeding remains difficult. As the mortality rate as well as the re-bleeding rate in blind segmental colectomy is very high, compared to the resection in patients, where bleeding site could be identified, the site of bleeding must found in any case.

Aged↗
PubMed2005

How to prevent low back pain.

This chapter summarizes the European Guidelines for Prevention in Low Back Pain, which consider the evidence in respect of the general population, workers and children. There is limited scope for preventing the incidence (first-time onset) of back pain and, overall, there is limited robust evidence for numerous aspects of prevention in back pain. Nevertheless, there is evidence suggesting that prevention of various consequences of back pain is feasible. However, for those interventions where there is acceptable evidence, the effect sizes are rather modest. The most promising approaches seem to involve physical activity/exercise and appropriate (biopsychosocial) education, at least for adults. Owing to its multidimensional nature, no single intervention is likely to be effective at preventing the overall problem of back pain, although there is likely to be benefit from getting all the players onside. However, innovative studies are required to better understand the mechanisms and delivery of prevention in low back pain.

Exercise Therapy↗
PubMed2005

Plant tissues: the frugal diet of mosquitoes in adverse conditions.

The plant tissue feeding of Anopheles sergentii Theobald, An. claviger Meigen, Culex pipiens Forskål and Aedes caspius Pallas (Diptera: Culicidae) was investigated. The relative frequency of plant feeding was compared to the general intake of sugar in different seasons and in different habitats in Israel. The study shows that mosquitoes feed on sugar-poor plant tissue in the lack of better options. Optimal conditions were in the sugar-rich En Fesha oasis, where plant tissue was found in only 0.3% of An. sergentii females, and, except for the winter, about 80% of females were sugar positive and the gut content was equivalent to 72.3 +/- 1.6 microg sucrose. By contrast, in the dry season in the desert, guts of 46.3% An. sergentii females contained plant tissue residues, only 46.0% were sugar positive, and the gut-content was less than a tenth, the equivalent of 5.6 +/- 0.9 microg sucrose. Age grouping of contemporary, desert An. sergentii showed that the growing population consisted mostly of newly emerged adults, as 80.2% of the females were nulliparous and only 12.1% of them survived one gonotrophic cycle.

Animals↗
PubMed2005

[Severe case of Candida peritonitis in a patient on CAPD--a successful treatment].

Continuous ambulatory peritoneal dialysis (CAPD) is a widespread method of treatment used in approximately 10% of all patients suffering from terminal renal insufficiency. The main problem of this procedure is the increased risk of peritoneal infection. The incidence of such a peritonitis is quoted at one episode per 13-18.4 months of treatment. Candida peritonitis is a particularly severe form of CAPD peritonitis. This is a nosocomial infection with a high lethality rate of about 60%. The incidence of Candida peritonitis in CAPD patients amounts to approximately 5% of all intraabdominal infections and is on the increase. The authors describe a severe case of Candida peritonitis in a patient on CAPD. The therapeutic concept of this severe illness is illustrated.

Adult↗
PubMed2005

Chemometric determination of blood parameters using visible-near-infrared spectra.

Visible and near-infrared (NIR) integrating sphere spectroscopy and chemometric multivariate linear regression were applied to determine hematocrit (HCT) and oxygen saturation (SatO2) of circulating human blood. Diffuse transmission, total transmission, and diffuse reflectance were measured and the partial least squares method (PLS) was used for calibration considering different wavelength ranges and selected optical measurement parameters. HCT and SatO2 were changed independently. Each parameter was adjusted to different levels and four designs with blood from different donors were carried out for the calibration with PLS. The calibration included the changes in hemolysis as well as inter-individual differences in cell dimensions and hemoglobin content. At a sample thickness of 0.1 mm the HCT and SatO2 were predicted with a root mean square error (PRMSE) of 1.4% and 2.5%, respectively, using transmission and reflectance spectra and the full Vis-NIR range. Using only diffuse NIR reflectance spectroscopy and a sample thickness of 1 mm, HCT and SatO2 could be predicted with a PRMSE of 1.9% and 2.8%, respectively. Prediction of hemolysis was also possible for one blood sample with a PRMSE of 0.8% and keeping HCT and SatO2 stable with a PRMSE of 0.03%.

Algorithms↗
PubMed2005

Knowing more by fewer measurements: about the (In)ability of bioelectric impedance to enhance obesity research in children.

The prevalence of obesity is increasing worldwide. The implications for human health can already be observed in children. Consequently, it is desirable to provide good quantitative descriptions of the relationship of body fat and health risks, such as hypertension. Bioelectric impedance analysis has been frequently praised to be useful for assessing body fat. Devices to analyse body composition based on this technique seem to be selling well, while the real gain in information they provide is unclear. Here we show in a cohort of 2,218 schoolchildren that the body mass index (which is more easily and less costly to determine) is a better predictor of hypertension than the data delivered by impedance analysis. Moreover, we demonstrate that the output of a random number generator is competitive with impedance measurement for this purpose. It is explained by simple arguments from physics why the formulas for the computation of body fat from bioelectric impedance obliterate rather than clarify the relationship of obesity and hypertension. As a consequence, we suggest questioning the opinion propagated by others that bioelectric impedance analysis is a useful tool in field studies on body fat in children. Measurements requiring more effort (compared to simpler methods) should be proved to add worthwhile information, otherwise they should be avoided.

Adolescent↗
PubMed2004

Geochemical features of topsoils in the Gaza Strip: natural occurrence and anthropogenic inputs.

The aims of this study were to establish the current contents of trace metals and major elements in agricultural soils of the Gaza Strip and to identify the main anthropogenic inputs affecting trace metal contents. An extensive soil survey was conducted in agricultural and nonagricultural areas. One hundred and seventy sites that represent a broad range of soil types and locations were selected. The results revealed that soils in the Gaza Strip fall within the range of uncontaminated to slightly contaminated. Up to 90% of the tested soils had trace metal contents equal to the international background values. Ten percent showed slight contamination, primarily by Zn, Cu, As, and Pb, due to anthropogenic inputs, and the mean concentrations of these elements were 180, 45, 13, and 190 mg/kg, respectively. The trace metal contents varied, with the highest contents detected in the southern regions (where one finds clay soil and low precipitation) and the lowest in the northern areas (where are sandy soil and high precipitation). The soil geochemistry is dependent on soil type and location and to a lesser extent on crop pattern and fertilizer and fungicide application. Anthropogenic inputs lead to the enrichment of Zn, Pb, Cu, and Cd in the agricultural soils. The pollution of several investigated sites was found to be most severe for Zn, Pb, Cu, Cd, and, to a somewhat lesser extent, for As, whereas anthropogenic input of Hg, Ni, and Co seemed to be less important. The application of Cd-containing phosphate fertilizers coupled with Cu-containing fungicides may be an important source of Cd and Cu in several soils. High Zn levels (1000 ppm) in several soils may be caused by sewage sludge, which has an average Zn content of 2000 ppm. Saline-sodic soils were found in the central and southern regions, where the soils are characterized by high contents of Na and salty groundwater. Elevated Cl, Na, Zn, and Pb contents in some areas need further investigation to determine their ecological and health implications.

Agriculture↗
PubMed2004

Development and evaluation of a new ELISA for the detection and quantification of antierythropoietin antibodies in human sera.

Assays for the analysis of antierythropoietin antibodies (anti-EPO Abs) currently suffer from a high degree of nonspecificity or are cumbersome and time consuming to perform. They are therefore not well suited for the analysis of large numbers of human sera samples, a task that has become increasingly important due to an increase in the number of patients developing anti-EPO Abs. The objective of this study was to develop and validate a sensitive and specific ELISA for the determination of anti-EPO Abs that would suit these purposes. In this new double antigen bridging ELISA, anti-EPO Abs bind via one site to recombinant human erythropoietin (rhEPO)-biotin immobilized to streptavidin-coated microtiter plates (MTPs) and by a second site to rhEPO labelled with digoxigenin (DIG). The amount of bound antibody is determined using an anti-DIG antibody coupled to peroxidase. A rabbit polyclonal anti-EPO Ab purified by immunoadsorption is used as reference antibody preparation. The dynamic range of this ELISA was 1-75 ng/ml per assay calibrated with the reference antibody preparation. The assay was specific for anti-EPO Abs and did not react with other immunoglobulins (Ig) present in human serum. The lower limit of detection (LLD) of the assay was 0.5 ng/ml, and the lower limit of quantitation (LLQ) was 1.0 ng/ml. Anti-EPO Abs could be detected in the sera of pure red cell aplasia (PRCA) patients. In contrast to previous reports, no anti-EPO Abs could be detected in the sera of patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Sjogren's syndrome (SS), or in the sera of dialysis patients.

Animals↗
PubMed2004

Fat oxidation at different intensities in wheelchair racing.

STUDY DESIGN: Determination of fat oxidation at three different intensities in trained wheelchair athletes on the treadmill. OBJECTIVE: The aim of the study was to assess the level and highest rate of fat oxidation in endurance-trained wheelchair athletes for recommendation on endurance training. SETTING: Institute of Sports Medicine, Swiss Paraplegic Centre, Nottwil, Switzerland. METHODS: Nine (seven men and two women) endurance-trained wheelchair athletes (VO(2peak) 40.2+/-6.7 ml/kg/min) were studied over 20 min at 55, 65 and 75% VO(2peak) on a treadmill in their own racing wheelchairs in order to find the exercise intensity with the highest absolute fat oxidation. RESULTS: As presumed, total energy expenditure for wheelchair racing was highest at 75% VO(2peak), while absolute fat oxidation was statistically not significantly different at the three tested intensities. Percentage of energy expenditure from fat oxidation decreased with increasing intensity from 31.4% at 55% VO(2peak) to 20.9% at 75% VO(2peak), while percentage from carbohydrate oxidation increased from 68.6% at 55% VO(2peak) to 79.1% at 75% VO(2peak). CONCLUSION: For wheelchair athletes, we recommend training of fat metabolism for endurance exercise at an intensity of 55% VO(2peak), because absolute fat metabolism is not higher at higher intensities but less carbohydrates are used at lower intensity levels. At lower intensities, exercise can be performed over a longer time before the emptied glycogen stores will limit exercise duration. This may apply especially to paraplegic subjects whose active muscle mass is limited in contrast to able-bodied athletes.

Adult↗