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M Bühler

Publications and source records attributed to M Bühler.

32 records · Page 2Linked to original sources
PubMed1983

[Nosocomial infections in a university hospital. Results of a prospective study of infections in a medical and surgical ward and a surgical intensive care unit].

The results of an 11-month pilot study of surveillance of nosocomial infections are reported. Prospective surveillance was performed by daily examination of the microbiology reports and daily visits by the infection control nurse to the ward for the review of charts and Kardex of all patients for detection of "infection clues". Work sheets were used to collect all data during the daily rounds. Infection rates were calculated by dividing the the total number of hospital-acquired infections by the total number of discharges during the surveillance period. Active surveillance was performed for 6 months in the surgical intensive care unit (SCIU), 5 months in the surgical ward (SW) and 9 months in the medical ward (MW). Of 1527 patients discharged from these wards, nosocomial infections developed in 158 patients (10.4%). The overall infection rate was 14% (214 nosocomial infections). The infection rate varied greatly from ward to ward due to different patient populations, invasive procedures and severity of underlying diseases. Incidence infection rates were 42.5% for the SICU, 19.6% for the SW and 4.1% for the MW. The major sites affected were surgical wounds (42%), urinary tract (23%), respiratory tract (19%) and bloodstream (8%). The major etiologic agents associated with these nosocomial infections were E. coli, Pseudomonas aeruginosa, enterococci and Staphylococcus aureus. Conclusions drawn from the results of surveillance are discussed. The major benefits of an effective surveillance program for nosocomial infections are (a) estimates of the endemic levels of nosocomial infection, (b) identification of the nosocomial pathogens commonly encountered within a given institution, (c) identification of risk factors and (d) prompt recognition of epidemics. These data provide the necessary basis for an effective infection control program.

Cross Infection↗
PubMed1982

On the kinetics and mechanism of enoate reductase.

Enoate reductases from Clostridium spec. La 1 and Clostridium kluyveri show a rather broad substrate specificity i.e. many alpha,beta-unsaturated carboxylates are reduced in a NADH-dependent reaction. The relative rates for different substrates are different for both reductases. The Km value of NADH for the reductase from C. spec. La 1 is about 12 muM. The transhydrogenase activity (reduction of N-acetylpyridine adenine dinucleotide) with NADH shows a maximum at pH 8 which is about 2 units higher than that for the reduction of enoates. Results of initial rate studies can be best explained by a Bi Bi ping pong mechanism. No back reaction and no proton exchange from 2(-3)H-labelled acylates could be demonstrated. NAD+ is a mixed-type inhibitor. The product inhibition constant Ki = 0.84mM and the dissociation constant for the dead-end inhibition complex 4.8mM. Aliphatic acylates show no measurable inhibition when they are applied in concentrations at the 100-fold Km values of the corresponding enoates. Measurable inhibitions can be observed with phenyl group-containing acylates. 3-Phenylpropionate (38mM) shows about 86% inhibition. Fumarate which is not a substrate inhibits the reduction of enoates by NADH as well as by reduced methylviologen. However, the reduction of NAD+ by reduced methylviologen as well that of acetylpyridine adenine dinucleotide by NADH is not inhibited by fumarate. On the other hand inhibitors such as morin or dicoumarol which probably bind to the flavin domain do not impair the reduction of enoates by reduced methylviologen however, all reductions with NADH are inhibited. These results are indicative for three binding domains: one for NADH which can be blocked by dicoumarol or morin, another for enoates which can be occupied by fumarate and a third one for reduced methylviologen. Enoate reductase splits off exclusively the (4S)-hydrogen atom from NADH. There is no direct hydrogen transfer from NADH to the products. Depending on the substrate concentration the isotope effect of the reduction of (E)-2-methyl-2-butenoate with (4S)-[4(-3)H]NADH varies from 6.8 to 1.3. The presence of NAD+ decreases the isotope effect.

Aerobiosis↗
PubMed1982

Rhein as an electron acceptor for various flavoproteins and for electron transport particles.

Rhein (4,5-dihydroxyanthraquinone-2-carboxylic acid) which has been previously employed as an inhibitor for electron transport particles, NADH dehydrogenase, and other flavoproteins is reducible under physiological conditions. Soluble hydrogenase from Alcaligenes eutrophus H 16, several flavoproteins, and electron transport particles from baker's yeast and from beef heart were found to catalyse NADH oxidation with 9 micrometers to 2mM rhein as the electron acceptor. Dithionite or enzymatically reduced rhein (lambda max = 408 nm) is immediately reoxidized to rhein lambda max = 437 nm) by oxygen. Cyclovoltagrams reveal the midpoint redox potentials --0.240 V, -0.270 V, -0.280 V, -0.335 V at pH 6.0, 7.0, 7.7, 9.2, respectively. Due to its redox behaviour, caution should be exercised using rhein as a flavin-site-directed inhibitor for biological electron transfer systems.

Alcaligenes↗
PubMed1981

[Sleeping behavior between the ages of 2 and 18. Longitudinal study].

Sleeping behavior was investigated in 320 Swiss children 2 to 18 years of age. The data were based on the First Zurich Longitudinal Study (1954-1980). The incidence of resistant behaviour at bedtime increased from 8 to 40% between age 2 and 10. Evening wakefulness was observed in 20% of the 2- to 7-year-old children, and in 40-50% of the older children. The incidence of night waking decreased from 40-50% in the preschool period to 20% at age 12.20% of the 2 to 4-year-old children and only 1% of the 12-year-old children woke up every night. Evening wakefulness and night waking were observed in some children over periods of several years. Up to age 5 the incidence of "bad dreaming" was 60%, subsequently it decreased to about 25%. Somnambulism was observed in 5% of the children. None of the described sleeping behaviors showed sex differences.

Adolescent↗
PubMed1980

[Quantitative whole-body bone scintigraphy. II. Pharmacokinetics of osteotropic radiopharmaceuticals (author's transl)].

85Sr, 99mTc-Sn-pyrophosphate and 99mTc-Sn-methylene-diphosphonate, the most important agents for skeletal imaging, are compared with each other by calculation of the plasma clearance and the urinary excretion and by a series of quantitative whole-body scans. 85Sr the distribution volume in equilibrium is the largest, shifting of activity is demonstrable for several days after injection. 99mTc-Sn-MDP is excreted most quickly, equilibrium is reached early. There is no significant difference in skeletal uptake between the phosphate complexes. The distribution however is different: 85Sr is localized to a greater extent in the extremities, the phosphate complexes more in the trunk, 99mTc-Sn-MDP and 85Sr nearer the joints than 99mTc-Sn-pyrophosphate.

Bone and Bones↗
PubMedDate not supplied

Transjugular intrahepatic portosystemic shunting (TIPS) with balloon-expandable and self-expanding stents: technical and clinical aspects after 3 1/2 years' experience.

PURPOSE: To evaluate prospectively our experience with transjugular intrahepatic portosystemic shunt (TIPS) using four different metallic stents. METHODS: Between November 1991 and April 1995, 57 patients (41 men and 16 women; age 35-72 years, mean 54 years) underwent the TIPS procedure. Techniques for portal vein localization before and during TIPS were fluoroscopy, computed tomography (CT) studies, wedged hepatic venography, arterial portography, and ultrasound. After predilation we deployed balloon-expandable (n = 48) and self-expanding (n = 45) metallic stents. Fifteen patients underwent variceal embolization. Initial follow-up angiograms (mean 6.9 months, range 3-24 months) were obtained in 39 of these patients. RESULTS: Fifty-three patients (93%) had successful TIPS placement. The mean decrease in portal pressure was 42.7%. Besides fluoroscopy, the most helpful techniques for portal vein localization were venography and CT. Residual stenosis (n = 1) and late shortening (n = 4) of Wallstents resulted in shunt dysfunction. The technical problems encountered with the Palmaz stent resulted from its lack of flexibility. We combined balloon-expandable and self-expanding stents in 12 patients. The 30-day and late follow-up (mean 11.9 months) percutaneous reintervention rates were 11.3% and 64.2%, respectively. There were no clinically significant complications related to the TIPS insertions. CONCLUSION: An ideal stent does not exist for TIPS, and the authors recommend combining a Palmaz stent with a flexible self-expanding stent.

Adult↗