Biomedical subjects

D Schnorr

Publications and source records attributed to D Schnorr.

113 records · Page 7Linked to original sources

PubMed1975

Evocability of a slight positive oestrogen feedback action on LH secretion in castrated and oestrogen-primed men.

Orchidectomized heterosexual men suffering from prostatic cancer with suppressed serum LH values by oestrogen priming exhibited a slight, but significant surge of LH secretion following oestrogen injection. In contrast, orchidectomized and oestrogen-primed heterosexual men with unsuppressed serum LH levels as well as intact heterosexual men did not display any positive oestrogen feedback action on LH secretion, as it was observed in intact homosexual men.

Aged↗

PubMed1975

An apparently direct inhibitory effect of oestrogen on the human testis.

In men suffering from prostatic cancer, i.v. administration of 12 g diethylstilboestrol diphosphate within 20 days resulted in a decrease of the LH serum level to about 50% (P less than 0.05), whereas the total testosterone level decreased to less than 5% (P less than 0.001) and the apparently free testosterone level to less than 2% of the initial values (P less than 0.001). Hence, the "systemic antiandrogenic effect" of oestrogen can be explained (1) by indirect inhibition of testicular androgen secretion via diminution of hypophyseal gonadotrophin secretion, (2) by direct inhibition of testicular androgen secretion and (3) by elevation of the capacity of testosterone binding beta-globulin.

Aged↗

PubMedDate not supplied

Tumor M2 pyruvate kinase in plasma of patients with urological tumors.

The M2 isoenzyme of pyruvate kinase (M2-PK) is specifically expressed in tumor cells (TU M2-PK) and may therefore provide a tumor marker for malignancies. We have investigated the plasma concentrations of TU M2-PK in patients with renal cell carcinoma (RCC), transitional cell carcinoma of the bladder (BCA), prostate cancer (PCA) and benign prostatic hyperplasia (BPH). TU M2-PK was quantified with a commercially available enzyme-linked immunosorbent assay (ELISA) kit. Using this ELISA kit, plasma samples of 57 healthy individuals were compared to 63 patients with RCC, 36 patients with BCA, 58 patients with PCA and 28 patients with BPH. Patients with carcinomas were subdivided into those patients with nonmetastatic and those with metastatic disease. Only patients with RCC (nonmetastatic and metastatic) showed significantly increased concentrations of TU M2-PK compared to normal individuals. In metastatic RCC, TU M2-PK levels were highest and were also significantly enhanced compared to nonmetastatic RCC. The sensitivity for nonmetastatic RCC was 27.5% and for metastatic RCC 66.7% at the 95% reference value of the control group. In BCA, PCA and BPH, no significant differences could be detected. Our results indicate that TU M2-PK concentrations in plasma may be a potential biomarker of advanced RCC.

Biomarkers, Tumor↗

PubMedDate not supplied

Soluble CD44 variants in the serum of patients with urological malignancies.

In patients with malignant diseases, characteristic alterations in the expression of CD44 protein and their variants were found. For the present study, the serum concentrations of the standard isoform CD44 std and the two variant isoforms CD44 v5 amd CD44 v6 were measured by ELISA in patients with prostate cancer (n = 49), benign prostatic hyperplasia (n = 30), renal cell carcinoma (n = 31) and bladder cancer (n = 29). The data were compared with the results of 30 healthy men and 30 healthy women. The sCD44 v5 concentrations in patients with prostate cancer (p < 0.01), benign prostatic hyperplasia (p < 0.01) and men with renal cell cancer (p < 0.01) were significantly lower than those measured in the male control group. The sCD44 v5 concentrations observed in male patients with bladder cancer were lower than in the male control group (p < 0.05). Only in one group the concentration of sCD44 std differed significantly from the others. The sCD44 std concentration in male patients with renal cell cancer was significantly lower than in the male control group (p < 0.01). Other significant differences were not found. In contrast to results observed in other carcinomas, the determination of soluble CD44 proteins in serum cannot be recommended as a marker for urological malignancies.

Adult↗

PubMedDate not supplied

Ratio of alpha 1-antichymotrypsin--prostate specific antigen to total prostate specific antigen in prostate cancer diagnosis.

OBJECTIVE: To evaluate the analytical performance and diagnostic utility of prostate specific antigen (PSA) bound to alpha 1-antichymotrypsin (ACT) in serum to improve the differentiation between benign prostatic hyperplasia (BPH) and prostate cancer (PCa). METHODS: A total of 351 white men 21 to 88 years old were analysed. Serum concentration of tPSA, free PSA (fPSA) and ACT-PSA were measured in 163 untreated PCa patients (median age 66 years), 94 patients with histologically or clinically confirmed BPH (median age 65 years) and 94 men without prostate disease considered as controls (median age 54 years). The Elecsys system 2010 (Roche Diagnostics, Germany) was used for the determinations of tPSA and fPSA. The ACT-PSA assay is a new developed prototype on the ES system (Roche Diagnostics, Germany). RESULTS: The ACT-PSA assay showed reliable data of analytical performance in comparison to established assays for tPSA and fPSA. The median concentrations of tPSA (PCa: 9.22 micrograms/L, BPH: 2.28 micrograms/L, controls: 0.99 microgram/L) and ACT-PSA (7.99 micrograms/L vs. 1.63 micrograms/L vs. 0.58 microgram/L) were significantly different, respectively. The median ratios of fPSA/tPSA (PCa: 12.3%, BPH: 25.4%), ACT-PSA/tPSA (90.5% vs. 66.6%) and fPSA/ACT-PSA (14.0% vs. 38.6%) were significantly different between PCa and BPH patients. Significant differences of ratios between BPH and controls were not observed. Receiver operating characteristics analysis (tPSA up to 20 micrograms/L) for discrimination between PCa and BPH showed that the ratios fPSA/tPSA (area under the curve: 0.861) and fPSA/ACT-PSA (0.847) were significantly different from tPSA (0.663), but ACT-PSA (0.733) alone and also the ratio of ACT-PSA/tPSA (0.780) were not significantly different from tPSA (0.663). CONCLUSION: The ratio fPSA/tPSA showed the best discrimination between BPH and PCa. The single or additional determination of ACT-PSA to tPSA does not improve the differentiation between the two groups of patients.

Adult↗