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Biomedical subjects

K Mann

Publications and source records attributed to K Mann.

At least 487 records · Page 27Linked to original sources

Determination of kallikrein by radioimmunoassay in human body fluids.

A sensitive and specific radioimmunoassay for human urinary kallikrein was developed, which allows tissue kallikrein determination in human urine, saliva, pancreatic juice, bile and sweat. In several body fluids a kallikrein-like antigen was found, but not in gastric juice and breast milk. According to gel filtration studies, complex formation of kallikrein with serum proteins or different molecular weight forms of kallikrein in serum and urine may be assumed. Pancreatic kallikrein secretion follows the same pattern after stimulation with secretin and cholecystokinin as trypsin and chymotrypsin in normal individuals. In chronic pancreatitis the kinetic behaviour remains unchanged with respect to the enzyme secretion, but the secretion of kallikrein is reduced to about 20%.

Body Fluids↗

Radioimmunoassay of human urinary kallikrein: determination of human urinary kallikrein, II.

A radioimmunoassay for the determination of human urinary kallikrein was developed. The sensitivity of the assay was 0.5 microgram/l. Dose-response curves of human submandibular and parotid saliva, sweat, pancreatic juice and bile paralleled the standard curve obtained with purified human urinary kallikrein. Substances with similar antigenic determinants were also found in human serum, ascites, seminal plasma, amniotic fluid, cervical mucus, tears, liquor and faeces, but not in human breast milk and gastric juice. Moreover, immunoreactive material was detected in the urine of guinea pigs, orangoutangs and chimpanzees, but not in the urine of rats, cats and rabbits. Porcine acrosin and kallikrein, as well as bovine trypsin and chymotrypsin, showed no cross reactivity.

Cross Reactions↗

Use of human chorionic gonadotropin and alpha-fetoprotein radioimmunoassays: specificity and apparent half-life determination after delivery and in patients with germ cell tumors.

The specificity of commercially available hCG and hCG-beta antibodies (anti-hCG-beta from N.I.A.M.D.D. (SB6), Serono (S), Biosigma (B), Union Carbide (UC) (I.R.E.) and anti-hCG from Union Carbide) were compared. Using 125I-hCG (CR 115), the crossreactivity with LH (LER 960) was 5.5% for SB6, 0.25% for S and 0.3% for B. In the homologous hCG system UC, crossreactivity was 0.06% with hCG-beta and 1.2% with LH, in the hCG-beta system UC, it was 2.2% with hCG and 0.01% with LH. Parallel standard curves for hCG, the 2nd I.R.P. hCG and hCG-beta were found exclusively with the 125I-hCG, anti-hCG-beta system S. Consequently accurate estimates of the total hCG or hCG-beta content in serum and standardization with the 2nd I.R.P. is possible. This system is the most useful for clinical purposes. The serum half-life of hCG was calculated in 10 pregnant women after delivery and was found to be 10 to 34 h. AFP half-life time, determined by the double antibody radioimmunoassay was 4.0 +/- 1.8 (+/- SD) days in pregnant women after delivery (n = 60) and 3.8 +/- 0.9 days in neonates during the first 16 days of life (n = 26). Altogether, apparent half-life determinations were carried out in 29 patients with nonseminomatous germ cell tumors. The results indicate that half-life determinations of hCG and AFP may have a predictive value with respect to the monitoring of therapy.

Antibody Specificity↗

[Comparative examination of endocrine ophthalmopathy by means of ultrasonography, computerized tomography and fish bioassay].

In 35 patients with Graves' ophthalmopathy (GO) thyroid function was tested by T3-RIA, T4-RIA, TBI, TRH-test, thyroid scanning, and determination of thyroid autoantibodies. Additional ultrasonography (A-scan), computed tomography (CT) of the orbit, and the determination of an exophthalmogenic serum activity in fish bioassay was performed. Typical alterations for GO were observed in 26 cases with ultrasonography. CT showed an enlargement of medial and/or lateral rectus muscles in 24 of 33 patients, and in 17 cases a region of high density in the apex of the muscle cone. The density of retrobulbar fat after i.v. injection of contrast medium did not differ significantly from that observed in normal men. Characteristic signs of GO were not detected in only 2 cases using both methods together. Exophthalmogenic serum activity was found in the IgG fraction of serum protein. The incidence rate was high (69%), but for diagnostic purpose the fish bioassay cannot be recommended.

Adult↗

Association of simian virus 40 T antigen with simian virus 40 nucleoprotein complexes.

Viral nucleoprotein complexes were extracted from the nuclei of simian virus 40 (SV40)-infected TC7 cells by low-salt treatment in the absence of detergent, followed by sedimentation on neutral sucrose gradients. Two forms of SV40 nucleoprotein complexes, those containing SV40 replicative intermediate DNA and those containing SV40 (I) DNA, were separated from one another and were found to have sedimentation values of 125 and 93S, respectively. [(35)S]methioninelabeled proteins in the nucleoprotein complexes were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In addition to VP1, VP3, and histones, a protein with a molecular weight of 100,000 (100K) is present in the nucleoprotein complexes containing SV40 (I) DNA. The 100K protein was confirmed as SV40 100K T antigen, both by immunoprecipitation with SV40 anti-T serum and by tryptic peptide mapping. The 100K T antigen is predominantly associated with the SV40 (I) DNA-containing complexes. The 17K T antigen, however, is not associated with the SV40 (I) DNA-containing nucleoprotein complexes. The functional significance of the SV40 100K T antigen in the SV40 (I) DNA-containing nucleoprotein complexes was examined by immunoprecipitation of complexes from tsA58-infected TC7 cells. The 100K T antigen is present in nucleoprotein complexes extracted from cells grown at the permissive temperature but is clearly absent from complexes extracted from cells grown at the permissive temperature and shifted up to the nonpermissive temperature for 1 h before extraction, suggesting that the association of the 100K T antigen with the SV40 nucleoprotein complexes is involved in the initiation of SV40 DNA synthesis.

Antigens, Neoplasm↗

[Computerized data processing for radioimmunoassay (author's transl)].

The computer programm of Marschner et al. ((1974), Arztl. Lab. 20, 184-191) for the calculation of radioimmunoassay data by spline functions was improved with regard to immediate availability of quality parameters. The existing programm was adapted to a computer Siemens 4004/151. Methods are reported for obtaining an exactly reproducible and objective smoothing of spline functions. The additional modifications enable even unskilled technicians to use the programm.

Computers↗

The Clarke SHQ: a clinical sex history questionnaire for males.

The development of a 225-item sexual history questionnaire is reported. The frequency, desire for, and disgust for a wide range of sexual behaviors, including anomalous behavior, were examined. Twenty-four scales were derived from factor analysis of the items. The scales were represented by modest unitary factors but were relatively free of bias from age, education, intelligence, social desirability, and defensiveness. The scales generally discriminated clinically relevant groups from control subjects and therefore meet a clinical need in the assessment of anomalous sexual behavior. The instrument also appears to be useful in examining hypotheses for research. Among these observations was the continuity between exhibitionism and heterosexual pedophilia and the apparent bisexuality of some homosexual males. The scale allows for the assessment of the preferences of sexually inexperienced males as well.

Attitude↗

Evidence for simian virus 40 (SV40) coding of SV40 T-antigen and the SV40-specific proteins in HeLa cells infected with nondefective adenovirus type 2-SV40 hybrid viruses.

HeLa cells infected with the nondefective adenovirus 2 (Ad2)-simian virus 40 (SV40) hybrid viruses (Ad2(+)ND1, Ad2(+)ND2, Ad2(+)ND4, and Ad2(+)ND5) synthesize SV40-specific proteins ranging in size from 28,000 to 100,000 daltons. By analysis of their methionine-containing tryptic peptides, we demonstrated that all these proteins shared common amino acid sequences. Most methionine-containing tryptic peptides derived from proteins of smaller size were contained within the proteins of larger size. Seventeen of the 21 methionine-containing tryptic peptides of the largest SV40-specific protein (100,000 daltons) from Ad2(+)ND4-infected cells were identical to methionine-containing peptides of SV40 T-antigen immunoprecipitated from extracts of SV40-infected cells. All of the methionine-containing tryptic peptides of the Ad2(+)ND4 100,000-dalton protein were found in SV40 T-antigen immunoprecipitated from SV40-transformed cells. All SV40-specific proteins observed in vivo could be synthesized in vitro using the wheat germ cell-free system and SV40-specific RNA from hybrid virus-infected cells that was purified by hybridization to SV40 DNA. As proof of identity, the in vitro products were shown to have methionine-containing tryptic peptides identical to those of their in vivo counterparts. Based on the extensive overlap in amino acid sequence between the SV40-specific proteins from hybrid virus-infected cells and SV40 T-antigen from SV40-infected and -transformed cells, we conclude that at least the major portion of the SV40-specific proteins cannot be Ad2 coded. From the in vitro synthesis experiments with SV40-selected RNA, we further conclude that the SV40-specific proteins must be SV40 coded and not host coded. Since SV40 T-antigen is related to the SV40-specific proteins, it must also be SV40 coded.

Adenoviruses, Human↗

Isolation of human urinary kallikrein by affinity chromatography. Determination of human urinary kallikrein, I.

Human urinary kallikrein (EC 3.4.21.8) was purified to electrophoretically homogeneity by gel filtration on Sephadex G-100, followed by affinity chromatography on aprotinin-Sepharose. The molecular weight, estimated by gel filtration, is 64,000 Daltons, by dodecyl sulfate electrophoresis 45,000 Daltons and 29,000 Daltons, and it is microheterogeneous on electrofocusing, yielding isoelectric point values of 3.8, 3.9 and 4.05. The kinetic constants for hydrolysis of BZArgOEt, TosArgOMe, CbzTyrONp, and human HMW-kininogen were determined. Benzamidine and aprotinin are competitive inhibitors of human urinary kallikrein.

Chromatography, Affinity↗

A kallikrein-specific inhibitor in rat kidney tubules.

A kallikrein inhibitor was found in tubules of the rat kidney and purified by chromatography on Sephadex G-100. The molecular weight of the inhibitor, estimated by gel filtration and dodecylsulfate electrophoresis, is about 4700. It inhibits the following kallikreins: porcine submanidbular and pancreatic kallikrein, rat kidney and urine kallikrein, and human urine and plasma kallikrein. An inhibition of bovine trypsin was not observed.

Animals↗