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D Svoboda

Publications and source records attributed to D Svoboda.

At least 19 recordsLinked to original sources
PubMed2005

Characteristics that promote transmission of Staphylococcus aureus nursing homes in German nursing homes.

OBJECTIVE: To determine factors that influence transmission of Staphylococcus aureus in nursing homes in the Rhine-Neckar region of southern Germany. DESIGN: Ecologic study. SETTING: Forty-seven nursing homes in the region. PARTICIPANTS: Residents of the approached nursing homes who agreed to participate. METHODS: Personal data and swabs of the nares were collected from participants. Swabs were examined for growth of S. aureus. All S. aureus isolates were typed using pulsed-field gel electrophoresis (PFGE). Transmission rates were calculated by dividing the number of transmissions (ie, cases in which two inhabitants shared the same PFGE type) by the number of S. aureus carriers. Characteristics of the nursing homes were correlated with a home's transmission rate. RESULTS: In each nursing home, 12% to 54% of the residents were colonized with S. aureus. The transmission rates for the 47 nursing homes ranged from 0% to 70%. A linear regression model revealed that a stay in the nursing home of longer than 6 months and accommodation in a room with 3 or more beds were positively associated with the transmission rate. Receipt of antibiotics during the 4 weeks preceding the study was negatively associated with transmission. CONCLUSIONS: Stays beyond 6 months and accommodation in rooms with multiple beds are important for the transmission of S. aureus. One way to reduce transmission would be to design facilities with single and double rooms. However, the social needs of the residents must be evaluated and respected.

Cross Infection↗
PubMed2002

Risk factors for methicillin-resistant Staphylococcus aureus carriage in residents of German nursing homes.

OBJECTIVES: To determine the prevalence of and the risk factors for methicillin-resistant Staphylococcus aureus (MRSA) carriage in nursing home residents in the Rhine-Neckar region of southern Germany. DESIGN: Point-prevalence survey. SETTING: Forty-seven nursing homes in the region. PARTICIPANTS: All residents of the approached nursing homes who agreed to participate. METHODS: After informed consent was obtained, all participants had their nares swabbed, some personal data collected, or both. All swabs were examined for growth of MRSA. All S. aureus isolates underwent oxacillin susceptibility testing and polymerase chain reaction for demonstration of the mecA gene. All MRSA isolates were typed using pulsed-field gel electrophoresis after digestion with SmaI. RESULTS: Swabs from 3,236 nursing home residents yielded 36 MRSA strains, contributing to a prevalence rate of 1.1%. Significant risk factors for MRSA carriage in the multivariate analysis were the presence of wounds or urinary catheters, limited mobility, admission to a hospital during the preceding 3 months, or stay in a medium-size nursing home. One predominant MRSA strain could be detected in 30 of the 36 MRSA carriers. CONCLUSIONS: The prevalence of MRSA in German nursing homes is still low. These residents seemed to acquire their MRSA in the hospital and transfer it to their nursing home. Apart from well-known risk factors for the acquisition of MRSA, we identified the size of the nursing home as an independent risk factor. This might be due to an increased use of and microbials in nursing homes of a certain size.

Aged↗
PubMed1997

Isolation and identification of new rapamycin dihydrodiol metabolites from dexamethasone-induced rat liver microsomes.

1. Rapamycin is metabolically transformed in rat liver microsomes to 3,4- and 5,6-dihydrodiol metabolites under the influence of the cytochrome P-450 mixed function oxygenase system. These metabolites were produced from dexamethasone-induced as well as from non-induced rat liver microsomes. The comparison of the ion spray mass spectra of the 5,6-dihydrodiol with the 3,4-dihydrodiol of rapamycin shows clearly that dihydrodiols were formed in two distinct positions of rapamycin. 2. FAB mass spectra as well as electrospray mass spectra of two additional peaks isolated from the same chromatographic run confirm the presence of a 3,4-dihydrodiol metabolite of rapamycin as also strongly suggested by UV spectra. Hplc reinjection of each individual peak always resulted in chromatograms showing a combination of the same three peaks and therefore are to be considered as tautomers of the 3,4-dihydrodiol of rapamycin. 3. These tautomeric conformations were found to have no immunosuppressive potency, most probably due to important structural and stereochemical modifications of the rapamycin binding domain to the binding protein (FKBP-12) and/or to important metabolic structural modifications of rapamycin effector domain.

Animals↗
PubMed1996

High-performance liquid chromatographic determination of tramadol in human plasma.

Tramadol has been determined in human plasma samples using a sensitive high-performance liquid chromatographic method. The plasma samples were extracted with tert.-butylmethyl ether in one-step liquid-liquid extraction (recovery 86%) and analyses of the extracts were performed on reversed-phase silica gel using ion-pair chromatography (verapamil as an internal standard) and fluorescence detection. The method was applied to the determination of tramadol levels in twelve healthy volunteers after oral administration of 100 mg of tramadol in capsules of Protradon and Tramal.

Administration, Oral↗
PubMed1996

Acute haemodynamic effects of diltiazem and its distribution in relation to the myocardial infarction size.

The aim of this study was to contribute to an elucidation of some possible mechanisms underlying harmful haemodynamic effects of calcium antagonist diltiazem in large myocardial infarctions in rats. Acute haemodynamic effects of i.v. diltiazem in a single dose of 0.5 mg/kg and the distribution of diltiazem in selected tissues was measured four weeks after surgical imposition of myocardial infarction in urethane (1.2 g/kg i.p.) anaesthetized rats. Hypotensive effect of diltiazem was significantly (r = 0.624) attenuated with an increasing infarction size. A significant relationship (r = -0.697) between change in stroke index and infarction size was observed. In rats with small infarctions (< 32% of the left ventricle circumference) there was an absolute increase, and in rats with large infarctions (> 32%) there was an absolute decrease in the stroke index. From the results obtained it seems likely that dilatation of ventricles without appropriate hypertrophy accompanying large infarctions is one of the main determinants of manifestation of negative inotropic potential of diltiazem.

Animals↗
PubMed1992

High-performance liquid chromatographic determination of ambroxol in human plasma.

Ambroxol has been determined in biological fluids using a rapid and sensitive high-performance liquid chromatographic method. The samples prepared from plasma by liquid-liquid extraction were analysed on reversed-phase silica gel by competing-ion chromatography with ultraviolet detection. The method was applied to the determination of ambroxol levels in twelve healthy volunteers after oral administration of 90 mg of ambroxol in tablets of Mucosolvan and Ambrosan.

Adult↗
PubMed1987

Comparative pharmacokinetics of four platinum cytostatics in rats.

The time-course of plasma and red blood cells platinum concentration was investigated after the administration of cis-dichlorodiammineplatinum II (cisplatinum), cis-dichlorodiammine-trans-dihydroxyplatinum IV (oxoplatinum), cis-dichloro-trans-dihydroxy-bis-isopropylamine-platinum IV (CHIP) and cis-diammine-1,1-cyclobutanedicarboxylate-platinum II (CBDCA) to male Wistar rats. A physiologically based three-compartment open model was used for pharmacokinetic evaluation. This model provides an estimation of free and protein-bound platinum time-courses from the total platinum species decrease. The total plasma clearance of total platinum increased in the order cisplatinum, CHIP, oxoplatinum and CBDCA. Plasma half-live of gamma-phase, which probably represents the elimination of protein-bound platinum species is similar (51-72 h) in all drugs under study and is longer than that of 131I-HSA (33 h). The platinum concentration in red blood cells shows plateau for all complexes studied at long time intervals and its elimination is very slow.

Animals↗
PubMed1973

Further evidence to suggest that microbodies do not exist as individual entities.

Male wild-type mice (Cs(a) strain) were treated with ethyl-alpha-p-chlorophenoxyisobutyrate (CPIB), a hypolipidemic drug which enhances hepatic catalase synthesis and induces rapid and significant increase in the number of microbody (peroxisome) profiles in liver cells. Numerous microbody profiles, several of them appearing in clusters and retaining membranous continuities, were observed in liver cells of CPIB-treated mice. They showed a significant variation in size and configuration, and the presence or absence of the nucleoid or core did not appear to bear any relation to the size or shape of microbody profiles. Nucleoids were encountered frequently in microbody profiles measuring as small as 0.1 mu in diameter. Numerous continuities between two or more anucleoid and/or nucleoid-containing microbody profiles of different sizes and shapes were seen. These findings are inconsistent with the concept that the smaller peroxisomes are the possible precursors or progenitors of their larger counterparts. Detailed examination of numerous electron micrographs revealed irregular dilatations and tortuosities of the endoplasmic reticulum (ER) containing electron-opaque peroxisomal material displaying the characteristic appearance of matrix and usually containing irregular cores. Transitions of rough ER to smooth ER in which microbody proteins accumulated were also apparent. Numerous continuities between several microbody profiles and continuities between microbody profiles and ER are interpreted as accumulations of peroxisomal proteins in dilated tortuous channels of ER. These observations strongly suggest that the microbody proteins constitute a common pool, circulating constantly in the dilated ER channels. The size, shape and number of microbody profiles appear to reflect the amount of peroxisomal proteins present in the pool. These observations clearly suggest that the microbodies do not exist as individual entities.

Animal Feed↗
PubMed1972

Microbodies in experimentally altered cells. IX. The fate of microbodies.

Male rats were given 0.25% CPIB (ethyl chlorophenoxyisobutyrate) for 4 weeks at which time their liver cells showed the typical increase in number of microbodies (peroxisomes). During the first week after withdrawal of CPIB and simultaneous injection of allylisopropylacetamide (AIA), an inhibitor of catalase synthesis, the microbody matrix, in peroxidase preparations, showed marked decrease in electron opacity. In liver cells of rats from which CPIB was withdrawn but which were not given AIA, there were interruption in the limiting membrane and almost total loss of microbody matrix within 3 days. Simultaneous with the loss of matrix content, the hepatic catalase activity decreased from an average 80 units/mg protein to less than 10 units/mg protein. In liver cells of Mastomys natalensis, a multimammate rodent, withdrawal of CPIB was associated with the frequent occurrence of bare microbody nucleoids situated free in the hyaloplasm. The ultrastructural observations and the associated decrease in catalase activity suggest that one means of disposal of microbodies is by rather rapid dissolution or leakage of their matrix enzymes into the surrounding hyaloplasm.

Acetamides↗