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Early detection of metastases in muscle-invasive bladder cancer is crucial. Current imaging techniques provide only limited sensitivity for the detection of low volume metastases. Molecular markers and new rapid analysis techniques are therefore needed to improve metastasis detection sensitivity. High urinary matrix metalloproteinase 7 (MMP 7) levels were previously shown to be correlated with the presence of lymph node metastases. In the present study we applied a new innovative antibody-based electrical biochip technology for the quantitative detection of urinary MMP 7.Preoperative urine samples were acquired from 30 bladder cancer patients (15xN0 and 15xN1-2) who underwent cystectomy because of muscle-invasive bladder cancer. In addition, urine samples of 15 age-matched healthy individuals were also collected. The MMP 7 analyses were performed using electrical biochip technology and a standard ELISA technique in parallel.Urinary MMP 7 concentrations measured by biochip technology were significantly higher in patients with metastatic bladder cancer compared to those with organ-confined cancer. The sensitivity for the detection of lymph node metastases was over 70 % using the biochip technology.These results confirm MMP 7 as a promising metastasis marker in bladder cancer. The new electrical biochip technology provides a rapid and reliable quantitative method for measurement of protein markers in urine.

Duisburg, Essen, Univ., Diss., 2003 Goals of this study are to point out strategies to influence the gel-matrix building components of biofilms. One well characterised component of the extracellular polymeric substances (EPS) of the bacterial strain Pseudomonas aeruginosa SG81 is the alginate AlgSG81. AlgSG81 is one main component of EPS and thus of the gel-matrix, too. AlgSG81 is completely dissociated in aqueous solution and therefore a strong polyelectrolyte (PEL). By means of computation with OSF-theory and validation via viscosity measurements the conformation of AlgSG81-chains in aqueous solution at screened and not screened conditions is that of a coil over a large concentration regime. By addition of tetramethylurea (TMU) to aqueous solutions of AlgSG81 the formation of a physical network (gel) is observed. Different empirical and theoretical approaches to characterise PEL were improved and experimental verified.

It is the aim of a series of investigations to test whether or not beta-pentachloro-1-cyclohexene is an intermediate in the biodegradation of alpha-hexachlorocyclohexane. This paper describes attempts to synthesize this intermediate by chemical methods. 1) Pentachlorocyclohexene was synthesized by partial additive chlorination of chlorobenzene. Combined gas chromatography-mass spectrometry revealed that at least five different isomers of pentachlorocyclohexene had been formed. 2) Treatment of alpha-hexachlorocyclohexane with alkaline buffer (pH 8) produced trichlorobenzenes and, in small yield (4%), a pentachlorocyclohexene. This was isolated and identified as the beta-isomer by melting point (71.8 - 72.6 degrees C, uncorr.), IR- and mass spectrum. Dehydrochlorination of beta-pentachlorocyclohexene produced the trichlorobenzene isomers in a pattern which is characteristic of alpha-hexachlorocyclohexane. The position of the chlorine substituents in the beta-pentachlorocyclohexene molecule as judged from NMR studies is e-aeee. This confirms that it is the monodehydrochlorination product of alpha-hexachlorocyclohexane. The configurations of gamma- and delta-pentachlorocyclohexene, determined for comparison, are e-eeaa and e-eeee, respectively. The kinetics of dehydrochlorination of both alpha-hexachlorocyclohexane and beta-pentachlorocyclohexene in alkaline acetone/water (3 + 2) was studied by means of conductometry. Both reactions are of second order: kappa alpha-HCH 0.0495 [1 times mol- minus 1 times s- minus 1[; kappa beta-PCH 0.905 [1 times mol- minus 1 times s- minus 1] (3.6 degrees C). 3) Dehydrochlorination of alpha-hexachlorocyclohexane in pyridine/xylene (3 + 4) was also studied. An earlier report claiming that gamma-pentachlorocyclohexene (and not the beta isomer) is produced in this medium was confirmed, if the reaction was performed at high temperature (120 - 140 degrees C). Moreover, the ratio of trichlorobenzene isomers formed from alpha-hexachlorocyclohexane shifted to a pattern characteristic of the gamma (or gamma) isomer. However, at temperatures of 90 degrees C or less, beta-pentachlorocyclohexene was the main product. The results strongly suggest that in pyridine/xylene, the same isomer is primarily produced from alpha-hexachlorocyclohexane and is isomerized to the gamma, delta and at least two other isomers of pentachlorocyclohexene before further dehydrochlorination ensues. A simple method for the synthesis of beta-pentachlorocyclohexene is presented.

Arteriovenous differences (AVD) of electrolyte concentration in the gut are followed by continuous conductometry of ultrafiltrates of portal venous and aortic blood. Intraduodenal application of tap water amounting to 0.5, 1,0 or 2,0% body weight lead to extremely variable reactions both in time course and dimension of AVD. Whereas large and fast changes can be described by a single exponential term, small and slow changes show saturation effects. Evidence is presented, that these differences correspond to permeability changes, both for water in the direction: lumen to blood and for electrolytes in the direction: blood to lumen. Thirst has an enhancing effect on AVD. A dual resorptive pathway is proposed to fit the data.

1. Na+ concentration, measured by the flame photometer, cryoscopic osmolality, and the specific electrolyte conductivity of urine show a close statistical correlation if only small amounts of a molecular disperse solution are dissolved in the urine. 2. Since conductance of a fluid is an expression of its ion concentration, better relationships exist between Na+ concentration and conductivity than between Na+ concentration and osmolality. 3. In the presence of large amounts of glucose in the urine, osmolality no longer represents the electrolyte content, and therefore no longer serves as a parameter of renal concentration power. On the other hand, the close correlation between conductance and Na+ concentration remains. 4. Conductometry supplements osmometry significantly by its selective capacity to determine electrolyte components in the urine. 5. Owing to the short time spent on the method and small errors in technique, it remains debatable whether conductometry is preferable to osmometry in normal cases for determining measurements in concentration in the urine.

The reproducibility (test-retest-reliability) of the forehead skin blood flow (method: fluvography or heat clearance) was tested by means of determination of the intraclass correlation coefficient. Defined changes of skin blood flow may be caused by loading a heat flow probe with weights; this was done in the range from 20 p to 500 p both in an ascending and a descending manner. A good reproducibility of results was reached in all repeated measurements made at intervals of one or several days. The correlation coefficient increases with increasing loads (r = 0.471 at a loading of 20 p; r = 0.813 at a load of 500 p).