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K Schulz

Publications and source records attributed to K Schulz.

At least 55 records · Page 3Linked to original sources
PubMed1997

How should we research unconventional therapies? A panel report from the Conference on Complementary and Alternative Medicine Research Methodology, National Institutes of Health.

Research in unconventional medicine requires a number of different questions to build up a "mosaic" of evidence. Choice of research design depends on the question being asked and is independent of the therapy under investigation. Despite the doubts of some practitioners, randomized trials are of value for determining certain questions in alternative medicine.

Complementary Therapies↗
PubMed1997

[Comparison between continuous and intermittent thermodilution measurement of cardiac output during coronary artery bypass operation].

PURPOSE OF THE STUDY: Continuous recording of cardiovascular parameters ranks high in cardioanaesthesia. Various methods to measure the cardiac output have been developed within a period of a few years. We compared the bolus thermodilution method (COI), which has been internationally adopted as "gold standard" method, with the continuous thermodilution method (CCO) for measuring the cardiac output by means of the CCO Vigilance Monitor. Our aim was to find out whether cardiac output can be determined with valid results during coronary artery bypass surgery when using CCO. METHOD: A flow-directed catheter was used (8 Fr. Intelli-Cath CCO PA) in 98 patients during coronary artery bypass surgery after initiation of anaesthesia, introducing the catheter via the right V.jugularis interna, for continuous measurement of the cardiac output via the CCO Vigilance Monitor. The same equipment was also used to measure the cardiac output via the bolus thermodilution method (COI mode) at the following stages: after abandoning the CCO mode 10 minutes subsequent to beginning the operation before sternotomy; 10 minutes after sternotomy before connecting to the heart-lung machine; 15 minutes after disconnecting the heart-lung machine before closing the thorax; and 10 minutes after closing the thorax. As a corresponding comparative value of the CCO method, we used the average cardiac output value calculated for each of the four times of measurement for the last three minutes before applying the boli. RESULTS: In regression analysis we chose the linear model CCO = b x COI with gradient b = 1 and zero point ordinate a = 0. The identity measures, Spearman's rank correlation coefficients, and linear regression coefficients calculated for the four times of measurement, showed good agreement. Scatter of the paired differences between both methods (CCO-CCI) did not have any deterministic structure at all times of measurement. The average bias at the 4 times of measurement was 0.10 l/min, -0.12 l/min, -0.1 l/min, and -0.03 l/min, respectively, with a precision = 2 x s of 1.17 l/min, 1.36 l/min, 1.69 l/min and 1.50 l/min, respectively. The average relative error (100 x [CCO-COI]/COI) with standard deviation was calculated for the 4 times of measurement as 3.2% (s = 15.4%), -1.6% (s = 15.3%), -0.9% (s = 13.9%) and -0.3% (s = 12.0%), respectively. CONCLUSIONS: Literature references show that the continuous thermodilution method is not only valid for intensive-care long-term measurement of cardiac output with approximately stationary haemodynamics, but also-as our results prove-valid if haemodynamics are not usually stationary, such as during coronary artery bypass surgery. The pros of the continuous thermodilution method are that no additional equipment is required apart from the standard equipment used in intensive-care medicine and cardio-anaesthesiology: that there is no stress caused by volume; and that manipulation is safe because no calibration routine is needed and also because measurement and analysis techniques are fully automated. Hence, we are of the opinion that the intraoperative use of this cardiac output measurement technique during open heart surgery is clinically indicated.

Aged↗
PubMed1997

Dynamics of Candida isolations from humans from 1992-1995 in Greifswald, Germany.

In the period 1992-95 there was a significant shift in the spectrum of Candida species in the University Hospital in Greifswald. During this time, the annual number of specimens taken for mycological investigations of adults increased threefold (total n = 11,568). The isolation rate of Candida species was 50.5%. The percentage of C. albicans isolates decreased from 76% to 54.4% with the lowest level in 1994. The opposite trend in the occurrence of non-C. albicans species was seen, for example the occurrence of C. glabrata, from 11.7% to 28.4%. We found only 98 strains of C. parapsilosis (1.4%) during the 4 years. The occurrence of Candida species in a variety of habitats was different. During the 4 years, the same annual percentages of C. albicans (mean 87.9%) were isolated from endoscopic oesophageal smears, whereas the distribution of Candida yeasts from the oral cavity, the respiratory tract, faeces and urine had changed. Over the years, at these locations, C. albicans was less frequently isolated and non-C. albicans species clearly increased. The highest occurrence of C. glabrata was found in urine, in which the isolation percentage almost doubled from 23.1% to 40.9% in 1994. In contrast to adults, in all specimens originating from a paediatric clinic that included neonatology the occurrence of C. albicans was high (83.5% in 1995), but the isolation rate of Candida species was low (12.3%). These results are important because of the differences in yeast susceptibility, of non-C. albicans species in particular, against antifungal drugs.

Adult↗
PubMed1997

[Candida identification: experiences with the Vitek automated system].

We report about our experiences obtained with the Vitek system (bioMerieux, Nürtingen) for identification of 1160 clinical Candida isolates. The Vitek system correctly identified 1005 (86.6%) Candida isolates (probability > or = 85%): 776 (66.9%) strains were identified after 24 h of incubation, 229 (19.7%) required 48 h of incubation. In 4.4% (n = 51) we found results with a lower probability (< 85%). After 24 h of incubation 38 (14.6%) of the 260 C. tropicalis isolates tested were misidentified as C. parapsilosis; we obtained the correct results after 48 h of incubation. 104 (9%) isolates were wrongly identified after 48 h of incubation. The majority of these strains (n = 82) were biochemically minimally reactive Candida species. Overall, the Yeast Biochemical Card system provides a reliable method for the rapid, automated identification of medically important Candida species.

Automation↗
PubMed1997

Patterns of sexually transmitted diseases in female sex workers in Surabaya, Indonesia.

Sex workers and their clients as core groups of high frequency transmitters play a dominant role in the transmission of HIV and other sexually transmitted diseases (STDs). In Surabaya, Indonesia, little is known about the prevalence of STDs in various sex establishments. We conducted an STD prevalence survey of 1873 female sex workers in Surabaya, Indonesia. We did not find any sex workers with HIV infection. Prevalence rates of other STDs (chlamydia, gonorrhoea, serological test for syphilis positive, and/or trichomoniasis) in female sex workers were 48% in brothels (n = 696), 42% on the streets (n = 192), 16% in massage parlours (n = 344), 25% in barber shops (n = 150), 17% at call-girl houses (n = 73), and 10% in nightclubs (n = 418). Sex workers from the brothels had the highest prevalence rates of gonorrhoea (24%) and trichomoniasis (8%), while sex workers from the streets and the barber shop had the highest rates of serological test for syphilis (STS) positive (30%) and chlamydia (18%). STD rates decreased with an increase in age (except for STS positive), an increase in education, a decrease in the number of sex partners, and condom use in the previous week. Condom use in the previous week was universally low among sex workers, especially among sex workers from the brothels (14%). Sex workers from the brothels had STD rates about 4 times higher than sex workers from the nightclubs (adjusted odds ratio of 4.4). Although the HIV seroprevalence rate is currently low, widespread prostitution and high rates of STDs in sex workers warrant programmes to avert a potential explosion of HIV transmission. Because sex workers from the brothels in Surabaya have high rates of STDs and low use of condoms but good cooperation with local authorities, STD preventive measures should focus on this group.

Adolescent↗
PubMed1996

Expression of phosducin in a phosducin-negative cell line reveals functions of a Gbetagamma-binding protein.

Phosducin is a member of the large group of proteins that bind to G-protein betagamma-subunits (Gbetagamma) and whose biological functions are often unknown. Human A431 cells do not contain detectable amounts of phosducin. We generated A431 cells expressing phosducin at a level of approximately 1 pmol/mg of cytosolic protein, which is approximately 10% of the phosducin level in brain. cAMP accumulation in response to beta2-adrenergic receptor agonists was enhanced at early times in phosducin-expressing cells, but reached a lower plateau than in control cells. Permeabilization of the cells with digitonin did not change this pattern, but allowed the introduction of specific inhibitors: antibodies to phosducin abolished all differences between the two cell lines. Inhibitors of the beta-adrenergic receptor kinase abolished the differences at early time points. An almost complete loss of beta2-adrenergic receptor desensitization in the phosducin-expressing cells was also observed when intact cells were desensitized and receptor function was then determined in membrane preparations. Inhibition of protein kinase A accentuated the effects of phosducin, suggesting that also in vivo phosducin is regulated by this kinase. These data indicate that phosducin affects G-protein-mediated signaling in at least two ways: it dampens the overall responsiveness, and it impairs the rapid desensitization mediated by the beta-adrenergic receptor kinase.

1-Methyl-3-isobutylxanthine↗
PubMed1996

[In vitro susceptibility testing of Candida species against fluconazole using the microdilution test with Alamar Blue].

The investigation of susceptibility of Candida species to fluconazole was performed in microdilution to a supplemented HR-medium. The sufficient reproducibility of the test was verified using special control isolates and isolates of patients. The excellent applicability of the method in routine diagnostics was evaluated by in vitro testing of susceptibility of 279 Candida isolates from patients being colonised or suffering from endomycoses. The Candida species showed different susceptibility against fluconazole: 96% of the C. albicans isolates were sensitive, 55% of the C. glabrata isolates had a reduced sensitivity, and 26% were resistant against fluconazole (MIC > 25 micrograms/ml). C. krusei isolates were highly resistant (9 of 11 strains).

Antifungal Agents↗
PubMed1996

What we have learned about bumetanide and the concept of multispecific bile acid/drug transporters from the liver.

Bumetanide is a weak organic acid which is transported into hepatocytes by a transport system that is related neither to the cloned sodium-dependent taurocholate cotransporting polypeptide Ntcp nor to the cloned organic anion transporting polypeptide oatp. Bumetanide is known to be transported in the kidney by a multispecific organic anion transporter which is the pAH-transporter from the proximal tubule cell. In the liver, bumetanide uptake competes with bile acid uptake, indicating a functionally related multispecific transporter for bile acids and drugs in hepatocytes. This multispecific bile acid transporter MBAT has not been cloned yet. When basolateral membranes were photoaffinity labeled with [3H]bumetanide, several bumetanide binding proteins were separated and identified after protein sequencing from two-dimensional electrophoresis gels.

Adenosine Triphosphate↗
PubMed1995

Sample size and statistical power in reproductive research.

The calculation of sample size should be an integral part of the planning stages of all research projects to avoid wasting time, money, and valuable resources. The necessary information for sample size calculations includes the alpha (type I) error level, the beta (type II) error, delta (or the difference you would like to be able to detect), and, for continuous variables, the variance. We review these terms and outline their importance in the calculation of sample size and statistical power. When necessary, the investigator should seek expertise and advice to perform these calculations.

Female↗
PubMed1993

Two different mRNAs from rat liver code for the transport of bumetanide and taurocholate in Xenopus laevis oocytes.

The aim of this study was to elucidate whether bumetanide, which is a competitive inhibitor of carrier mediated bile acid uptake in liver cells, is transported by bile acid carriers. The expression of hepatocellular transport proteins for bile acid uptake and the uptake of the loop diuretic bumetanide was therefore studied in Xenopus laevis oocytes by injection of rat liver poly(A)(+)-RNA. Three hours after injection, a 70% increase in [3H]taurocholate uptake versus noninjected oocytes was accompanied by an increase in only 24% in the uptake of [3H]bumetanide. Size fractionation of the poly(A)(+)-RNA yielded 33 mRNA fractions of which fraction 21 accounted for an 800% increase of taurocholate transport with only a slight increase in bumetanide uptake. Bumetanide transport was coded by mRNA-fraction 18, which stimulated uptake by 160-200% with a concomitant small increase in taurocholate uptake. Uptake of cholate was induced by both mRNA fractions with almost 2.5 fold greater expression by the bumetanide fraction. Oocyte transport of taurocholate (expressed by fraction 21) and bumetanide transport (expressed by fraction 18) were characterized in terms of Na+ dependency, inhibition by 4,4'-diisothiocyano-1,2-diphenylethane-2,2'-disulfonic acid (DIDS) and mutual competition. The results indicate that the bumetanide transporter mRNA is clearly different from the mRNA for the taurocholate transport protein. The mRNA fraction 18 was used for the construction of a cDNA library.

Animals↗