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M Exner

Publications and source records attributed to M Exner.

At least 37 records · Page 2Linked to original sources
PubMed2004

Cerebrospinal fluid neuron-specific enolase in non-selected patients.

The degree to which cerebrospinal fluid (CSF) neuron-specific enolase (NSE) contributes to the diagnosis and prognosis of disorders of the central nervous system (CNS) or peripheral nervous system (PNS) is still under debate. The aim of the study was thus to assess the validity of CSF-NSE levels in the diagnostic work-up of these conditions. The study consecutively included 106 adult patients who had undergone a diagnostic spinal tap or myelography during the diagnostic work-up for various CNS or PNS disorders. Thirty-five of these patients (16 F, 19 M, aged 24-88 years) without indication of a CNS disorder and with normal routine CSF investigations served as controls. The remaining 71 patients (31 F, 40 M, aged 28-87 years) constituted the disease group. CSF-NSE was independent of sex and age. The upper reference limit of CSF-NSE was 0.01536 ng/L. CSF-NSE was elevated in 13 of the 71 patients (18%): 6 with metabolic myopathy, 4 with polyneuropathy and 3 with hepatic encephalopathy, multiple sclerosis and paraspasticity, respectively. Only 6 of the 13 patients (46%) showed CNS involvement. The study shows that CSF-NSE is elevated in only one-fifth of unselected patients who consecutively undergo a spinal tap. CSF-NSE is elevated most frequently in patients with metabolic myopathy and polyneuropathy, even in cases without CNS abnormalities.

Adult↗
PubMed2004

The size of a microsatellite polymorphism of the haem oxygenase 1 gene is associated with idiopathic recurrent miscarriage.

Endothelial damage, impaired microvascularization and immune maladaptation have been described as aetiological factors in recurrent miscarriages. We investigated the relationship between idiopathic recurrent miscarriage (IRM) and a (GT)(n) repeat microsatellite polymorphism of the gene encoding haem oxygenase 1 (HO-1), known to modulate immune functions such as T-helper (TH) cell function and to be associated with cardiovascular disease. We investigated 162 women with IRM and 129 healthy, post-menopausal controls. The length of the HO-1 (GT)(n) microsatellite was assessed by PCR and direct sequencing in all women. Results were correlated with clinical data. The distribution of genotypes was in Hardy-Weinberg equilibrium. The HO-1 (GT)(n) microsatellite repeat numbers ranged from 13 to 37, with (GT)(23) and (GT)(30) being the most common alleles in both groups. We compared alleles consisting of < or =27 GT repeats, termed class S (short) alleles and alleles consisting of >28 GT repeats, termed class L (long) alleles. Seventy per cent of women with IRM had an S allele either in heterozygous (L/S) or homozygous (S/S) form, compared to 56% of controls (P = 0.02; OR 0.54; 95% CI 0.32-0.90). With respect to S allele frequencies, we found no significant difference among women with IRM and controls [P = 0.3; odds ratio (OR) 1.23, 95% confidence interval (CI) 0.86-1.76]. Comparing women with primary and secondary IRM, no difference with respect to the length of the HO-1 (GT)(n) microsatellite was ascertained. In summary, this is the first report on a HO-1 (GT)(n) microsatellite polymorphism among women with IRM, demonstrating that the investigated polymorphism is associated with IRM in a relatively large Caucasian population.

Abortion, Habitual↗
PubMed2003

Impact of portable air filtration units on exposure of haematology-oncology patients to airborne Aspergillus fumigatus spores under field conditions.

We undertook a one-year study to investigate the impact of the NSA model 7100A/B portable air filtration unit on exposure of haematology-oncology patients to airborne Aspergillus fumigatus spores under field conditions. Weekly measurements for airborne A. fumigatus were conducted in indoor and outdoor air, and surveillance for invasive aspergillosis was based on a combination of ward liaison, targeted chart review and consultation with the medical staff. The mean indoor A. fumigatus counts (8.1 cfu/m3; range, <0.8 to 42 cfu/m3) reflected the fungal load of outdoor air (9.4 cfu/m3; range, <0.8 to 50 cfu/m3), and were reduced by only about one third in rooms with portable air filtration units (5.3 cfu/m3; range, <0.8 to 41 cfu/m3). During the study period, a total of five cases (incidence density, 0.8 per 1000 patient-days) of invasive aspergillosis (one proven case, four suspected cases; case fatality rate 40%) were recorded. None of these five patients was allocated to a room with portable air filtration unit, however, the difference between incidence densities in rooms with and without portable air filtration units was non-significant (Fisher's exact test, P=0.33). Due to the noise level and thermal discomfort, patient compliance with the air filtration units was poor. We conclude that under field conditions this air filtration unit cannot be recommended for prevention of invasive aspergillosis in neutropenic haematology-oncology patients.

Adult↗
PubMed2003

Use of the oral glucose tolerance test to define remission in acromegaly.

An oral glucose tolerance test (OGTT) was used to assess growth hormone (GH) secretion in patients with acromegaly prior to (n = 26) and after (n = 71) transsphenoidal adenomectomy as well as in 196 controls. In controls, suppressed concentrations of GH showed a negative relationship both with body mass index (BMI) and with age. Having calculated the reference intervals for suppressed GH concentrations to be expected for any given age and BMI, we compared these individually predicted ranges to GH concentrations actually observed in patients with acromegaly during OGTT. Preoperatively, concentrations exceeded the normal range in all patients. Postoperatively, glucose-suppressed concentrations of GH were less than 2.0 ng/mL in 56 (79%) patients and less than 1.0 ng/mL in 44 (62%). However, only 37 of 71 (52%) patients had glucose-suppressed GH concentrations within the calculated reference intervals (defined by the 95th percentile of normal). Comparing these data with the patient's concentrations of insulin-like growth factor-1 (IGF-1; normal range first established and corrected for age and sex in 494 healthy individuals), congruency of both parameters was found in 59 (77%) patients with an unexplained discrepancy between GH and IGF-1 in the remaining in 16 (23%) patients. Our results confirm that concentrations of IGF-1 must be corrected for sex and age, whereas glucose-suppressed concentrations of GH depend on age and BMI. "Across-the-board" cut-off-values are clearly inadequate and should not be used. Rather, serum GH measurements obtained during an OGTT must be interpreted individually by comparison to control values taking into account both age and BMI.

Acromegaly↗
PubMed2003

Adrenocortical tumors: prevalence of impaired glucose tolerance and of "Paradoxical Rise" of cortisol during an oral glucose tolerance test.

Glucose tolerance and the behaviour of cortisol during an oral glucose tolerance test (OGTT) was investigated in 126 patients with adrenal "incidentalomas" (age: > 45 years) and in 129 age-matched controls. Impaired glucose tolerance (IGT) was found to be more common (p < 0.02) among patients with adrenal incidentalomas. Subdividing these patients by their body weight it was found that 29% (controls: 25%) of those with normal body weight (BMI 20 - 25 kg/m2) had IGT/DM. In overweight (BMI 25 - 30 kg/m2) and obese patients (BMI 30 - 40 kg/m2) the share of IGT/DM was 32% (controls: 19%) and 66% (controls 42%), respectively. The prevalence of a "paradoxical" rise in serum cortisol concentrations during the OGTT was slightly higher (p < 0.05) among patients with adrenal incidentaloma than among controls. Patients as well as controls with this abnormal behaviour of cortisol were characterized by lower basal serum cortisol concentrations (p < 0.01) but no association was seen with either the presence of IGT or with post-dexamethasone concentrations of serum cortisol. Thus both in patients with and without adrenal incidentalomas abnormal glucose tolerance is an age- and weight-dependent phenomenon unrelated to the post-prandial behaviour of serum cortisol concentrations.

Adrenal Cortex Neoplasms↗
PubMed2003

Severe Serratia liquefaciens sepsis following vitamin C infusion treatment by a naturopathic practitioner.

A 66-year-old female patient developed severe Serratia liquefaciens sepsis following vitamin C infusion treatment by a naturopathic practitioner. The clinical course of the infection was characterized by several complications, and the direct costs of the hospital stay amounted to about 40000 Euro. Genotypically identical S. liquefaciens was isolated from the residue of the infusate given to the patient, as well as from the washbasin overflow and from two other infusion bottles. A careful inspection of the dispensing facilities and review of procedures used to prepare the infusate revealed several indications of poor hygiene. However, the source of contamination could not be fully clarified. This case report raises questions about the local facilities and personal qualifications required for naturopathic practitioners to conduct invasive procedures and demonstrates that lapses in hygiene can lead to severe morbidity and high cost.

Aged↗
PubMed2002

Homocysteine promotes the LDL oxidase activity of ceruloplasmin.

Ceruloplasmin (CP) oxidises low density lipoprotein (LDL). The oxidising potential depends on the formation of Cu(+)-CP which is redox-cycled during oxidation. Homocysteine (HCY) reduces free Cu(2+), potentiating its cell-damaging property. We show that HCY enhanced LDL oxidation by CP, but did not activate the LDL oxidising potential of Cu(2+)-diamine oxidase. Selective removal of the redox-active Cu(2+) abolished the LDL oxidase activity of CP. However, HCY partially restored the LDL oxidase activity of redox-copper depleted CP, indicating that the remaining six copper atoms in CP may also be involved in the process. Spectroscopic and oxidation inhibition studies using the Cu(+)-reagent bathocuproine revealed that HCY induced Cu(+)-CP formation, thus promoting its LDL oxidase activity.

Ceruloplasmin↗
PubMed2002

The higher disinfectant resistance of nosocomial isolates of Klebsiella oxytoca: how reliable are indicator organisms in disinfectant testing?

The Children's Clinic in Giessen, Germany recently reported several severe infections with Klebsiella oxytoca resulting in deaths of two neonates. The putative source of the infections was a contaminated infusion solution. The resistance to disinfectant of the K. oxytoca isolates was investigated in three independent laboratories and was indeed found to be significantly increased. Comparative tests with standard strains of K. oxytoca and other recommended bacterial surrogates showed the disinfection procedures used were fully effective. The higher resistance of the nosocomial isolates may have developed due to improper handling and storage of the cleaning utensils. This report describes the events and draws conclusions concerning the use of disinfectants, the treatment of cleaning utensils, the reliability of procedures for testing disinfectants, and suggests additional measures.

Adolescent↗
PubMed2002

Pseudomonas aeruginosa outbreak in a haematology-oncology unit associated with contaminated surface cleaning equipment.

An outbreak of six cases of hospital-acquired Pseudomonas aeruginosa infections (two pneumonia two septicaemia, two skin/wound infection) occurred between August and September 2000 in an adult haematology-oncology unit at a tertiary-care centre. During the outbreak, hospital-acquired infection (HAI) incidence density rates rose from 29.4 to 62.3 (P < 0.05) infections per 1000 days at risk (i.e., neutropenic days). A systematic outbreak management system was actioned in accordance with a German draft guideline. Multiple samples from the patients' environment were tested for the presence of P. aeruginosa. A total of 4.5% of samples from sanitary equipment and 20.0% of samples from surface cleaning equipment were found to be contaminated with P. aeruginosa. Genotypic analysis by pulsed-field gel electrophoresis showed different patterns for all (N = 6) of the patient isolates, however, two of the patient isolates were identical in comparison with environmental isolates from cleaning equipment (four samples) and sanitary equipment (one sample). Our investigation revealed that the cleaning staff had used cleaning solution instead of disinfectants for decontamination of the patients' environment. The outbreak was terminated after re-adoption of surface disinfection, application of sterile filters on taps and shower heads, chemical disinfection of the washbasin drains, and appointment of a hospital hygiene nurse to a previously unfilled position. After institution of the control measures, HAI incidence densities decreased to pre-outbreak level. This investigation emphasizes the need to carefully evaluate cleaning and disinfection practices for patient care, particularly in neutropenic patients.

Adult↗
PubMed2002

[Reprocessing of flexible endoscopes and endoscopic accessories - an international comparison of guidelines].

Endoscopic examinations and procedures are essential for diagnosis and treatment of gastrointestinal diseases. As a result of poor reprocessing practice microorganisms can be transmitted via endoscope. The majority of infection transmissions is due to insufficient performance of cleaning and disinfection disregarding guidelines of societies of gastrointestinal endoscopy. A review of the literature and a comparison of European and American guidelines for reprocessing flexible endoscopes are given. Differences in the classification of endoscopic devices, on the possibility of prion transmission, recommendations on staff training and protection, quality assurance of reprocessing and evidence-based graduation of guidelines are stressed and discussed. With respect to the procedure of endoscope reprocessing, differences concerning the cleaning solution to choose, necessity of thoroughly manual cleaning and brushing of the accessible endoscope channels (even in the case of subsequent automatic reprocessing endoscopes in washers-disinfectors), disinfection solution, microbiological quality of water for final rinsing and rationale for alcohol flush of endoscope channels for better drying are mentioned. The need for experimental investigations of the cleaning and disinfection process is stressed. In contrast to recent guidelines of European and American societies of gastrointestinal endoscopy, the now updated recommendations of the Robert Koch-Institute for reprocessing flexible endoscopes and endoscopic accessories are evidence-based and graduated.

Cross Infection↗
PubMed2002

Microbial load of drinking water reservoir tributaries during extreme rainfall and runoff.

Hygienic and microbiological examinations of watercourses are usually not carried out during heavy rainfall and runoff events. After rainfall or snowmelt, there are often massive increases in turbidity in flooding creeks in mountain ranges, which are frequently interpreted as an indication of microbial contamination. The aim of this study was to quantify the microbial loads of watercourses during such runoff events and to compare these loads with loads occurring during regular conditions. In a 14-month monitoring period we investigated the microbial loads of three tributaries of different drinking water reservoirs. A total of 99 water samples were taken under different runoff conditions and analyzed to determine physical, chemical, bacterial, and parasitic parameters. Thirty-two water samples were considered event samples during nine measuring series. The criteria for events, based on duration and intensity of precipitation, water depth gauge measurements, and dynamics, had been fixed before the investigation for each creek individually. Of the physical and chemical parameters examined, only the turbidity, pH, and nitrate values differed clearly from the values obtained for regular samples. Most of the bacteriological parameters investigated (colony, Escherichia coli, coliform, fecal streptococcal, and Clostridium perfringens counts) increased considerably during extreme runoff events. If relevant sources of parasitic contamination occurred in catchment areas, the concentrations of Giardia and Cryptosporidium rose significantly during events. The results show that substantial shares of the total microbial loads in watercourses and in drinking water reservoirs result from rainfall and extreme runoff events. Consequently, regular samples are considered inadequate for representing the microbial contamination of watercourse systems. The procedures for raw water surveillance in the context of multiple-barrier protection and risk assessment ought to include sampling during extreme runoff situations.

Rain↗
PubMed2002

Hand hygiene.

Explore the source record for details and available documents.

Disinfection↗
PubMed2001

Kinetic and mechanistic studies of the NO*-mediated oxidation of oxymyoglobin and oxyhemoglobin.

The second-order rate constants for the reactions between nitrogen monoxide and oxymyoglobin or oxyhemoglobin, determined by stopped-flow spectroscopy, increase with increasing pH. At pH 7.0 the rates are (43.6 +/- 0.5) x 10(6) M(-1) x s(-1) for oxymyoglobin and (89 +/- 3) x 10(6) M(-1) x s(-1) for oxyhemoglobin (per heme), whereas at pH 9.5 they are (97 +/- 3) x 10(6) M(-1) x s(-1) and (144 +/- 3) x 10(6) M(-1) x s(-1), respectively. The rate constants for the reaction between oxyhemoglobin and NO* depend neither on the association grade of the protein (dimer/tetramer) nor on the concentration of the phosphate buffer (100-1 mM). The nitrogen monoxide-mediated oxidations of oxymyoglobin and oxyhemoglobin proceed via intermediate peroxynitrito complexes which were characterized by rapid scan UV/vis spectroscopy. The two complexes MbFe(III)OONO and HbFe(III)OONO display very similar spectra with absorption maxima around 500 and 635 nm. These species can be observed at alkaline pH but rapidly decay to the met-form of the proteins under neutral or acidic conditions. The rate of decay of MbFe(III)OONO increases with decreasing pH and is significantly larger than those of the analogous complexes of the two subunits of hemoglobin. No free peroxynitrite is formed during these reactions, and nitrate is formed quantitatively, at both pH 7.0 and 9.0. This result indicates that, as confirmed from protein analysis after reacting the proteins with NO* for 10 times, when peroxynitrite is coordinated to the heme of myoglobin or hemoglobin it rapidly isomerizes to nitrate without nitrating the globins in physiologically significant amounts.

Animals↗
PubMed2001

A common C-->T polymorphism at nt 46 in the promoter region of coagulation factor XII is associated with decreased factor XII activity.

Coagulation factor XII (FXII) deficiency is rarely found to be associated with bleeding, but single reports demonstrated thromboembolic events in FXII-deficient patients. Currently, the biological role of FXII is still discussed controversially. It is well known that plasma levels of FXII show great interindividual variability. Recently, it has been demonstrated that a frequently occurring C-->T polymorphism in the FXII promoter region at nucleotide (nt) 46 is associated with lower plasma FXII activity levels in Orientals. In our study, we evaluated the frequency of this polymorphism in a randomly selected sample of newborns and investigated whether this C-->T polymorphism also contributes to the frequently observed moderate FXII deficiency in Europeans. We developed a new mutagenically separated polymerase chain reaction assay (MS PCR), which allows mutation detection without the use of restriction enzymes. Among 100 healthy newborns, we found 64% homozygous carriers of the wildtype FXII 46C allele, 29% were heterozygous for FXII C46T, and 7% homozygous for FXII 46T. Evaluation of plasma FXII activity and genotype in 80 randomly selected and unrelated individuals revealed a highly statistically significant (P<.001) association of the FXII 46T allele with reduced FXII plasma activity. Individuals carrying the homozygous FXII 46C genotype had a mean of 1.17 U/ml (+/-0.31 U/ml), individuals heterozygous for FXII C46T showed a mean of 0.70 U/ml (+/-0.31 U/ml), and subjects homozygous for FXII 46T had only 0.44 U/ml (+/-0.10 U/ml) plasma FXII activity.

Alleles↗
PubMed2001

p-Hydroxyphenylacetaldehyde, the major product of tyrosine oxidation by the activated myeloperoxidase system can act as an antioxidant in LDL.

The oxidative modification of low density lipoprotein (LDL) may play a significant role in atherogenesis. HOCl generated by the myeloperoxidase/H2O2/Cl- system of activated neutrophils may be operative in vivo making LDL atherogenic. Tyrosine has been found to be oxidized by HOCl to p-hydroxyphenylacetaldehyde (p-HA) capable of modifying phospholipid amino groups in LDL. As an amphiphatic phenolic compound, p-HA may have the potential to act as an antioxidant in the lipid phase of LDL. The present results show that (a) tyrosine exerts a protective effect on LDL modification by HOCl, (b) p-HA could act as antioxidant associated with the lipoprotein preventing cell- and transition metal ion-mediated LDL oxidation and (c) p-HA was able to scavenge free radicals.

Acetaldehyde↗
PubMed2001

Semicarbazide-sensitive amine oxidase catalyzes endothelial cell-mediated low density lipoprotein oxidation.

OBJECTIVE: Deamination products of semicarbazide-sensitive amine oxidases (SSAO), i.e. aldehydes, superoxide and ammonia have been shown to initiate vascular damage. SSAOs are copper-enzymes, present in endothelial (EC), smooth muscle cells (SMC) and in blood. Transition metals ions (Cu, Fe) mediate the oxidative (atherogenic) modification of LDL by SMC and EC. The physiological source of the active metal ions is still under debate. We hypothesize that SSAOs may catalyze LDL oxidation by endothelial cells via enzyme-complexed Cu++. METHODS: EC isolated from human umbilical veins and cultured in 35 mm wells in RPMI-1640 medium were used as LDL oxidation system. RESULTS: Diamine oxidase (DAO), a SSAO which activity is elevated in tissues and sera of diabetic patients, catalyzes the oxidation of LDL by EC. In the presence of purified DAO (0.07 to 70 U/l) LDL oxidation was increased up to 10-fold as measured by thiobarbituric acid reactive substance (TBARS) formation as well as apoprotein modification of LDL. Chemical blockage of the SSAO substrate binding site did not inhibit the catalytic effect of DAO on LDL oxidation. Denaturation of the enzyme did not destroy the ability of the preparation to facilitate LDL oxidation by EC. The potential of the enzyme to catalyze LDL oxidation was not suppressed in the presence of serum. However, selective removing of enzyme-copper completely abolished the ability of the enzyme to trigger cell-mediated LDL oxidation. CONCLUSION: DAO, beside generating angiopathic deamination products, has the potential to act as a pathophysiological catalyst of LDL atherogenic modification by vascular cells.

Amine Oxidase (Copper-Containing)↗