Search PubMed⌕ Search

Biomedical subjects

H Fiedler

Publications and source records attributed to H Fiedler.

At least 19 recordsLinked to original sources
PubMed1996

Sources of PCDD/PCDF and impact on the environment.

PCDD/PCDF can be formed in a variety of industrial and thermal processes. Especially the combustion sources contribute to the ambient air levels. In addition to the well-investigated emissions from municipal waste incinerators dioxins were measured in the flue gases of other thermal emitters. It was found that some recycling plants can emit high concentrations of PCDD/PCDF. Ambient air concentrations monitored over several years have shown a clear seasonal trend with higher PCDD/PCDF levels in winter and lower concentrations during summer. Thus, results from short-term measurements cannot be used to calculate annual means for ambient air concentrations or deposition rates. Dioxins, once concentrated in sewage sludge and compost can re-enter the environment when these "reservoirs" are applied onto agricultural and horticultural soils.

Air Pollution↗
PubMed1994

[The diagnostic significance of alpha-MSH in malignant melanoma of man].

In malignant melanoma, melanocyte-stimulating hormone (alpha-MSH) has been found to influence the cellular metabolism of melanoma cells (c-AMP production, protein and RNA synthesis, and tyrosinase activation). In some publications elevated alpha-MSH levels have been described in melanoma patients. In the present study we used a commercially available radioimmunoassay to examine the alpha-MSH levels in patients with malignant melanoma and a control group consisting of apparently healthy volunteers (laboratory assistants) and dermatological patients without malignant tumours. The plasma alpha-MSH levels were (mean +/- SD) 12.2 +/- 12.9 for 37 melanoma patients (17 female, 20 male) and 7.9 +/- 3.5 pmol/l for 38 control persons (18 female, 20 male). The difference is significant according to the distribution-free U-test of Mann and Whitney. In 13 (35%) of the melanoma patients values were above the normal range defined by the 95.5% confidence limit. alpha-MSH cannot be classified as a typical tumour marker. Nonetheless, in our opinion alpha-MSH levels may be useful in monitoring melanoma patients with reference to prognosis and follow up during and after therapy.

Biomarkers, Tumor↗
PubMed1994

[The clinical value of plasma fibronectin in pregnancy].

We have measured plasmatic fibronectin in 23 normotensive pregnant women during pregnancy (overall 161 values). On the average 6 samples from every woman have been taken. Plasmatic fibronectin rose continuously from 313 +/- 76 mg/l in the first trimester to 416 +/- 194 mg/l in the third trimester. Normal pregnant women (n = 173, 358 +/- 140 mg/l) were compared with pregnant patients with preeclampsia (n = 37), woman with chronic hypertension in pregnancy (n = 25) and normotensive pregnant patients with intrauterine growth retardation (IUGR, n = 5). In the group with chronic hypertension (466 +/- 119 mg/l) there was no significant difference to the normal group, but we found a significant (p < 0.01) different value of fibronectin (748 +/- 195 mg/l) in the group of patients with preeclampsia. A tendency to higher fibronectin values was also noticed in the group with IUGR (739 +/- 212 mg/l). Because of the low number of patients this difference was not statistically significant. We conclude, that plasmatic fibronectin is an important, but not absolutely specific screening parameter for estimation of the endothelial injury in hypertensive disorders of pregnancy. We believe, that fibronectin is one the best parameters to forecast a preeclampsia.

Adult↗
PubMed1993

[Inguinal recurrence after therapeutic lymphadenectomy in malignant melanoma].

In a retrospective study, 73 stage-II melanoma patients with 22 superficial and 51 deep groin dissections were observed over a maximum of 9 years of follow up (median 67.5 months). The 5-year survival rate of 29.8% was consistent with that yielded by comparable analyses of other investigators. However, the probability of recurrence in the node dissection field was as high as 35%. All groin recurrences occurred in the first 29 months after lymph node clearance (median 6 months). Patients with groin recurrence following lymph-node dissection had a poor prognosis (median survival 12 months). In a multifactorial analysis (Cox model), the only prognostic factor of probability of recurrence was the development of regional in-transit cutaneous metastases (p = 0.0028). Factors that did not affect the appearance of recurrent metastases in the node dissection field were: site of primary melanoma, tumor thickness, epidermal ulceration, degree of lymph node involvement (p = 0.2) age, sex, degree of surgery (superficial or deep groin dissection) and adjuvant chemotherapy. Because regional in-transit cutaneous metastases mostly occur synchronously with groin recurrence or later, they are a typical concomitant phenomenon rather than a prognostic factor of recurrence.

Chemotherapy, Adjuvant↗
PubMed1993

[Axillary recurrence after lymph node excision in malignant melanoma].

In a retrospective study 143 patients with 155 axillary lymphadenectomies were observed with a maximum of 8 years of follow-up (mean 51.9 +/- 25.8 months). At the time of their lymphadenectomies, 39 patients had histologically negative nodes (stage I), 85 patients lymph-node metastases (stage II), 19 patients axillary node involvement and distant metastases (stage III). The estimated 5-year survival rates were 77.5% in stage I and 28.6% in stage II. Axillary recurrence after dissection of tumor-free lymph nodes rarely happened, but in stage II the probability of recurrence was as high as 30.7%. All axillary recurrences occurred in the first 20 months after lymphadenectomy. In a multivariate analysis (Cox model), the only prognostic factor of probability of recurrence in stage II was the development of regional in-transit cutaneous metastases (p = 0.048). Factors that did not affect the appearance of recurrent metastases in the node dissection field were: epidermal ulceration, vascular invasion, tumor thickness, degree of lymph-node involvement, age, sex, and adjuvant chemotherapy. Median survival after axillary recurrence following therapeutic lymph-node excision (5 months) was comparable with survival after lymphadenectomy in stage III (7 months). There was a high incidence (> 30%) of regional in-transit cutaneous metastases in both groups. Regardless of the poor prognosis, we found 15% axillary recurrences after lymph-node clearance in stage III.

Combined Modality Therapy↗
PubMed1991

Quantitative binding studies of a monoclonal antibody to immobilized protein-A.

Binding constants and column capacities are important factors for evaluating an affinity chromatography system. Scatchard plots based on classical equilibrium binding have been used to demonstrate how association constants and column capacities can be computed from simple binding experiments and a commercial computer program. The analysis has been demonstrated on a monoclonal antibody type IgG-1 Kappa against Serratia marcescens nuclease and a commercial protein-A column, Prosep-A. Additional analyses were performed with the same antibody and other protein-A affinity systems and the different binding constants and column capacities obtained confirmed the value of the analysis for evaluating an affinity system.

Antibodies, Monoclonal↗
PubMed1990

Fermentation studies of the secretion of Serratia marcescens nuclease by Escherichia coli.

The secretion of a Serratia marcescens nuclease was followed by fermentation with Escherichia coli. A plasmid, p403-SD2, carrying a 1.3-kilobase-pair insert with a 0.4-kilobase-pair region upstream of the nuclease gene caused a growth-phase-regulated expression of nuclease in E. coli in the same way as that seen in S. marcescens. Deletion of the regulatory gene generating plasmid p403-Rsa1 resulted in a constitutive expression of the nuclease. Anaerobiosis stimulated the expression from p403-SD2 in stationary growth phase by a factor of 10 compared with expression stimulated by cultivation in aerobic conditions; no such effect was found for plasmid p403-Rsa1. Different nutritional factors caused the expression level and the amount of extracellular nuclease to vary more when nuclease was expressed from plasmid p403-SD2 than when it was expressed from plasmid p403-Rsa1. A correlation between the regulatory gene and the extracellular secretion of nuclease is proposed.

Bacteriological Techniques↗
PubMed1990

[Results of a randomized polychemotherapy study in malignant melanoma].

A polychemotherapy (DTIC, vincristine, ftorafur, hydroxycarbamide) devised with reference to the results of short-term sensitivity tests in cell culture is compared with single-agent chemotherapy with DTIC in malignant melanoma. Effectiveness was investigated in a randomized prospective study in cases of high-risk melanoma in clinical stage I, in clinical stage II after lymphadenectomy and in clinical stage III after tumour debulking. The results recorded allow no positive effects of either form of chemotherapy in stage I disease compared with surgical treatment only in a control group. In contrast, a statistically significant advantage of the polychemotherapy was noted in stage II compared with a control group. There was no significant difference in the results of treatment between the two forms of chemotherapy in stage III. No complete remissions of long duration have been achieved.

Adolescent↗
PubMed1990

[Requirements of intensive care medicine for laboratory diagnosis].

The effective utilization of the laboratory diagnostics in the intensive care medicine requires a close co-operation between physician and laboratory diagnostician beginning from discriminated requests and the faultless specimen collection until the computerised evaluation and interpretation. Out of the numerous necessary parameters of investigation special attention is directed to the assessment of the electrolyte and water balance, the transcapillary exchange and the oxygen consumption. In the following years the laboratory diagnostics has to meet important demands which result from pathobiochemical research conclusions with critically ill patients.

Acid-Base Equilibrium↗