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Biomedical subjects

R Nagel

Publications and source records attributed to R Nagel.

At least 127 records · Page 7Linked to original sources
PubMed1982

[The effect of lacquer coatings on indoor air quality using as example radiator lacquers].

Examination of the air of a redecorated office room revealed the lacquer used to paint the radiators as one of the possible reasons for complaints by persons working in that room. The dry lacquer was found to contain solvent residues and considerable amounts of aldehydes (from propanol to n-nonanal), in particular of n-hexanal. In model studies, the details of aldehyde formation have been elucidated. An electric radiator was painted twice with special radiator lacquer, allowed to dry for 3 days and placed into a 1 m3 glass cube. The cube was continuously purged with clean air, simulating air exchange rates of 0.6 and 0.15 per hour. During the experiment, air samples were taken at intervals of several days and analyzed by gas chromatography. The temperature of the radiator was varied between 40 and 60 degrees C. In addition to the different aldehydes which appeared in the air of the cube each at concentrations of up to the mg/m3 range, remarkable concentrations of the corresponding carboxylic acids were found. In analogy to the aldehyde series with a predominance of n-hexanal, there was a maximum concentration of 50 mg/m3 of n-hexanoic acid in the air of the cube. Taking as an example n-butyric acid, which has an odour threshold value of appr. 4 micrograms/m3, the values measured in the cube were used to calculate the corresponding indoor air concentration in a room of 50 m3 with an air exchange rate of 0.6 per hour. It was found that even after a 4-weeks operation of such a radiator, the odour threshold value was surpassed by a factor of 3. By using other types of lacquers (e.g. water-soluble lacquers), the occurrence of such aldehydes and carboxylic acids in indoor air can be largely prevented.

Air Pollutants↗
PubMed1981

Problems of assessment in the surgery of renal adenomas.

We report 6 cases of renal adenomas in which difficulties were encountered in the determination of malignancy. The clinical and anatomical data are discussed, particularly the difficulties with the histological frozen section diagnosis of such tumors, together with the therapeutic outcome. The objective of a differentiating procedure is to increase the number of operations with organ conservation, while avoiding metastasis that could be derived from apparently benign renal adenomas.

Adenoma↗
PubMed1981

[CEA, HCG-beta and alpha fetoproteins - clinical significance as tumor markers].

Representation of the clinical significance of the tumor markers CEA, HCG-beta and alpha 1-fetoprotein (AFP) of the basis of the relevant literature and of own studies. As a marker for tumors of the urogenital tract, CEA is at present of very little value as it is too unspecific. HCG-beta and AFP, on the other hand, are important new parameters for both the demonstration of so-called subclinical metastases (staging) and clinical case control, particularly with malignant nonseminomatous tumors of the testicles. Over a period of four years we found in 62 out of 85 patients with nonseminomatous testicle tumors that -- in accordance with the literature -- simultaneous determination by the two markers (85% positive) is decidedly superior to the determination by one marker only. Out of 23 patients with a histologically classified seminoma, one patient (i.e. 4.4%) was HCG-beta positive. So far, the prognostic significance of such findings has generally not been clarified. It is shown here that exclusively "marker-oriented" therapy planning and case control without the clinical examination methods used so far are not yet justified because of the inadequate specificity and sensitivity of these two markers as well as of more recent ones (SP-1, TPA). Nevertheless, HCG-beta and AFP are at present important new methods in the areas of diagnosis (staging), therapy planning and case control as primarily increased marker values, or marker values increased during or after therapy clearly indicate metastasizing or renewed tumor activity, respectively.

Adult↗
PubMed1981

[Concentration of cefamandole in human renal parenchyma (author's transl)].

(6R-[6alpha,7beta(R)])-7-[(hydroxyphenylacetyl)amino]-3-([(1-methyl-1H-tetrazol-5-yl)-thio]methyl)-8-oxo-5-thia-1-azabicyclo[4,2,0]oct-2-ene-2-carbonic acid (cefamandole) levels have been determined in human renal tissue, serum, and urine of 17 patients undergoing therapeutic nephrectomies after 3 i.v. applications of 2 g cefamandole. As far as possible levels of renal cortex and renal medulla were investigated separately. The concentrations of the antibiotic in human renal tissues, removed in the interval from 2 h 10 min to 6 h 25 min after last application of the drug, were distinctly above the minimum inhibitory concentrations of most bacterial strains responsible for urinary tract infections and cases of chronic pyelonephritis. Concentrations of the drug were usually lower in renal parenchyma alterated by chronic inflammatory processes than in "normal tissue" of tumor kidneys. With separate determinations of drug levels in the cortical and medullary regions concentrations of the drug were usually higher in the cortical part of the kidney.

Adult↗
PubMed1980

Lavage of cytology of the renal pelvis and ureter with special reference to tumors.

Lavage cytology was done in 101 patients with radiological filling defects in the ureter and renal pelvis. This simple and inexpensive technique is valuable in the preoperative diagnosis of tumors of the ureter and renal pelvis. In our series it was possible to recognize clearly 29 of 36 such tumors (80.5 per cent) through preoperative lavage cytology. No falsely positive diagnoses were made. Lavage cytology failed in 6 patients with hypernephroma. The diagnostic reliability of lavage cytology with urothelial tumors is far greater than that of exfoliative urine cytology and reaches almost equally good results as brush biopsy.

Diagnosis, Differential↗
PubMed1980

[Measurement of urethral closure pressure profiles with stress performed by CO2-infusion in stressincontinent women: sources of error in methodology and modes of clinical application (author's transl)].

The measurement of urethral closure pressure with stress is limited by the compressibility of gasiform mediums, which causes damping of intraurethral pressure spikes. In this study damping could be reduced by alterations of the catheter and the connecting tubes of an aircystometer. With this modified technique 55 incontinent women were examined. The differentiation between stress- and urgeincontinence was clinically sufficient.

Adult↗
PubMed1980

Sickle cell disease in Sicily.

The chemical and physical properties of haemoglobin S derived from homozygotes for this haemoglobin in Sicily were examined, as well as some erythrocytic characteristics. Sicilian Hb S was identical to that found in USA black patients in electrophoretic mobility on both starch and citrate agar media, solubility, mechanical precipitation rate of oxyhaemoglobins, and minimum gelling concentration, as well as by peptide mapping and amino-acid analysis of all beta-chain peptides. Taken together with the presence in Sicily of African blood group markers and certain historical considerations, it seems clear that the source of Hb S in Sicily is Africa. While the clinical severity in nine Sicilian children did not seem remarkably different from the disease in the USA, the most severe and fatal complications were not seen. Mean Hb F Was 10.5% and 2,3-diphosphoglycerate (2,3-DPG) values were higher in Sicilian homozygotes than in black USA counterparts (21.79 mumol/g Hb vs 15.16). Red cell AT values were also slightly higher in Sicilian patients. The presence of concomitant thalassaemia was excluded by both family studies and globin chain synthetic ratios. In conclusion, haemoglobin S in Sicilian homozygotes is identical to Hb S found in USA blacks. Although the severity of the disease seems quite similar in both groups of patients, other erythrocytic properties were found to be different. Whether these factors influence severity remains to be elucidated.

Adenosine Triphosphate↗
PubMed1980

Estracyt therapy of advanced prostatic cancer with special reference to control of therapy with cytology and DNA cytophotometry.

81 patients with advanced prostate carcinoma, mainly estrogen resistant, were treated with Estracyt. After a pilot study had shown encouraging results in the first 39 cases, the preparation was used on a further 42 patients and for 38 of these its therapeutic effectiveness was evaluated according to internationally defined clinical criteria. In this way, an objective therapeutic success quota of 55% of all 38 patients was obtained. In the group with estrogen-resistant tumors the value was still found to be as high as 35%. These clinical results were confirmed by cytomorphological control of the degree of regression of the tumor effected by the therapy, and also by single-cell cytophotometric analysis of the DNA content of various prostate carcinomas treated wtih Estracyt.

Biopsy, Needle↗
PubMed1980

Cytological and DNA-cytophotometric monitoring of the effect of therapy in conservatively treated prostatic carcinomas.

A total of 464 aspiration biopsies were carried out on 180 patients with variously treated prostatic carcinomas. Characteristic signs of regression could be detected cytomorphologically in the cell nucleus and cytoplasm, which permitted 6 different regression grades to be distinguished. Analysis of 102 punch and aspiration biopsies, carried out for the first time simultaneously, revealed a diagnostic reliability of at least 97%. The incidence of complications on aspiration biopsy was 1.7%. In 30 cases additional prospective single cell DNA determinations were carried out on advanced prostatic carcinomas undergoing treatment. It could be shown that tumors with extensive aneuploidization and lack of change in the ploidal distribution in response to treatment showed poor clinical progress whereas those in which a change from aneuploidy to euploidy became apparent, showed good clinical progress.

Biopsy, Needle↗
PubMed1979

[Tobramycin concentrations in human renal tissue (author's transl)].

Investigation of kidneys from 20 patients revealed relatively low tobramycin concentrations in cortex and medulla after one day of treatment. After administration for several days a significant accumulation was observed in only one of three patients. Attention is drawn to the higher tobramycin concentrations found in renal parenchyma which has undergone chronic inflammatory changes compared to the "normal" values in kidneys infiltrated by tumours. A higher accumulation thus occurs in renal tissue which has already undergone structural damage as a result of bacterial inflammation.

Adult↗
PubMed1979

[The cytologic differentiation of prostatis (author's transl)].

INTRODUCTION: Cytologists are often confronted with unexpected prostatitis in aspiration biopsy smears, because clinically prostatitis may lead to suspicious induration of the prostate similar to carcinoma and therefore subject to diagnostic biopsy. The question is whether cytodiagnosis is a reliable method for the exact morphologic diagnosis of prostatitis. The following paper attempts to answer this question. MATERIAL AND METHODS: The basis of our cytologic differentiation of prostatitis was a series of 129 cases of prostatitis in 664 aspiration biopsies according to Franzén. In 82 of these 129 cases, we had simultaneously performed a transrectal needle punch biopsy, which allowed a diagnostic comparison between the cytologic and histologic diagnosis with special reference to the reliability of cytology. Epithelial atypias were classified into 4 grades: Grade 1: No atypia; Grade 2: Slight atypia; Grade 3: Marked atypia; Grade 4: Malignant epithelium. Cytomorphologic characteristics of each grade are described. RESULTS: We found 6 different types in 4 main groups of prostatitis: 1. Acute prostatitis, purulent and abscessing types. 2. Chronic prostatitis. 3. Chronic relapsing prostatitis. 4. Granulomatous prostatitis, non specific and specific types. All types showed classic cytomorphologic inflammatory criteria. Marked atypias were found in group 3 and 4. Differential diagnosis with respect to carcinoma is not difficult, however, because marked atypias in these groups of prostatitis almost always appear focally. The diagnostic agreement between cytology and histology in 82 cases was found to be 87,6%. DISCUSSION: Our results showed that prostatis may be adequately diagnosed with cytology and may be differentiated into 6 different types. However, differentiation between periductal and interstitial forms of chronic prostatitis is impossible with cytology. Reliable cytodiagnosis of prostatitis requires a good aspiration smear, so that at least one half of slide is covered with material from the prostate. Furthermore, epithelial atypias must be present to prove the presence of prostatitis. Because of the good reliability of the cytologic differentiation of prostatitis, aspiration biopsy may be a valuable aid to the clinician in the primary diagnosis of prostatitis, especially the chronic type, which currently is sometimes uncertain.

Acute Disease↗