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Biomedical subjects

J Tamm

Publications and source records attributed to J Tamm.

At least 37 records · Page 2Linked to original sources
PubMed1982

The effect of the antiandrogen II alpha-hydroxyprogesterone on sebum production and cholesterol concentration of sebum.

II alpha-Hydroxyprogesterone, a synthetic antiandrogen of low toxicity, was applied topically. In short-term experiments the sebum production of the forehead in normal male subjects was reduced significantly. The cholesterol concentration of sebum decreased to a greater extent. In long-term studies in patients with seborrhoea and male-pattern alopecia, the steroid caused a marked and constant reduction of greasiness of the hair. In this group also, the cholesterol concentration of the sebum obtained from scalp hair decreased more markedly than total sebum production. Possible effects of II alpha-hydroxyprogesterone on androgenic alopecia are discussed.

Adult↗
PubMed1981

A single base-pair alteration is responsible for the DNA overproduction phenotype of a plasmid copy-number mutant.

The Cop- plasmid pOP1 delta 6 is a recessive copy-number mutant derived from Col E1.pOP1 delta 6 exists at 200-300 copies per chromosome in E. coli, while Col E1 exists at 10-15 copies per chromosome. We have investigated the molecular basis for DNA overproduction by pOP1 delta 6 by mapping the mutation to a restriction fragment of the plasmid genome, which is about 400 bp from the origin of replication. The mutation is a single base-pair alteration-a GC leads to TA transversion. The alteration changes the nucleotide sequence of two RNA elements known to be synthesized from opposite DNA strands in the same region of the plasmid genome; a small, nontranslated RNA known as RNA1 and the primer RNA required for initiation of DNA replication in vitro. The mutation is located in a GC-rich region of dyad symmetry, which precedes the termination signal for RNA1 transcription. When pOP1 delta 6 DNA is transcribed in vitro, RNA1 is not observed. Rather, several new transcripts of a larger size are observed resulting from readthrough transcription of RNA1. In conjunction with previous genetic evidence, these results indicate that RNA 1 may be a negative modulator of Col E1 DNA replication and that its secondary structure is critical to its function.

Base Composition↗
PubMed1981

Unconjugated 5 alpha-androstan-3 alpha, 17 beta-diol and 5 alpha-androstane-3 beta, 17 beta-diol in human plasma as measured by radioimmunoassay without chromatography.

A radioimmunoassay (RIA) without chromatography for the determination of 5 alpha-androstan-3 alpha, 17 beta-diol and of 5 alpha-androstane-3 beta, 17 beta-diol in human plasma by using highly specific antisera against the 15 beta-carboxyethylmercapto-bovine serum albumin conjugates is described. It could be shown that the 13% cross reaction of the 5 alpha-androstane-3 beta, 17 beta-diol antiserum with pure androst-5-ene-3 beta, 17 beta-diol was negligibly low in plasma extracts. Sensitivity, accuracy, precision, and linearity revealed results which comply with the requisites of a reliable RIA. The plasma levels obtained were as follows (mean +/- SD): 5 alpha-androstan-3 alpha, 17 beta-diol: Normal males (N = 27) 0.86 +/- 0.22 nmol/l; normal females (N = 10) 0.31 +/- 0.07 nmol/l; hirsute females (N = 25) 0.60 +/- 0.24 nmol/l; 5 alpha-androstane-3 beta, 17 beta-diol: Normal males 1.47 +/- 0.43 nmol/l; normal females 0.49 +/- 0.10 nmol/l; hirsute females 0.91 +/- 0.32 nmol/l.

Androstane-3,17-diol↗
PubMed1980

[Extended diagnosis for lesions of the capsule and the ligament of the knee joint (author's transl)].

X-rays taken under mechanical positioning of the joint with standardized conditions are helpful aids in the diagnosis of injuries of the knee capsule and ligaments. In comparison to the non-affected knee the extent of instability of the joint can be exactly demonstrated. Arthrography is of little help in fresh injuries to the knee capsule and ligaments, but can be useful to assess the residuals of old damage to the joint. Arthroscopy has its place mainly in the diagnosis of old injuries and hardly any in fresh lesions. In general, however, arthroscopy is a very valuable diagnostic procedure.

Bursa, Synovial↗
PubMed1980

Plasma testosterone glucosiduronate: a reliable indicator of female hyperandrogenism (idiopathic hirsutism and androgenic alopecia).

Plasma concentrations of testosterone glucosiduronate (TG) have been determined by direct radioimmunoassay in seventeen normal females, twenty females with idiopathic hirsutism, and in twelve female subjects with androgenetic alopecia without hirsutism, respectively. The corresponding mean concentrations (+/- SD) of TG were 0.47 +/- 0.18; 1.42 +/- 0.55; 0.96 +/- 0.22 ng/ml. There was no overlapping of plasma TG levels of both groups with hyperandrogenism with those obtained in normal females. On the contrary, plasma concentrations of testosterone and dihydrotestosterone were found within the normal ranges in about 50% of the patients with hyperandrogenism. The synchronously estimated urinary excretion of TG revealed marked fluctuations (mean +/- SD): 27.0 +/- 12.0; 60.5 +/- 24.6; 36.3 +/- 14.1 microgram/24 h respectively.

Adult↗
PubMed1980

Short-term response of testosterone, dihydrotestosterone, 5 alpha-androstane-3 beta, 17 beta-diol, testosterone-glucosiduronate and estradiol-17 beta as measured in the spermatic vein of human male subjects after infusion of gonadotropins.

In 8 male subjects with normal testicular function, blood was drawn from the left spermatic vein and from the right cubital vein before and during an infusion of 4,000 IU human chorionic gonadotropin (hCG) (preceded by a bolus of 1,000 IU) or of 500 IU hCG plus human menopausal gonadotropin (hMG), respectively, within 30 min. Testosterone levels in the spermatic vein blood increased rapidly up to 518 or 215%, respectively. An increase of estradiol-17 beta and of 5 alpha-dihydrotestosterone concentrations in spermatic vein blood was observed only in 1 and 2 subjects, respectively. It was shown that the human testicle releases also 5 alpha-androstane-3 alpha, 17 beta-diol and testosterone-glucosiduronate. Both steroids did not respond to the short-term infusion of gonadotropins. The same holds true for all five steroids measured in peripheral vein blood.

Adult↗
PubMed1979

Isolation of highly purified sex hormone binding globulin (SHBG): evidence for microheterogeneity.

Highly purified sex hormone binding globulin (SHBG) was isolated in milligram amounts from a human serum fraction (Cohn IV-4). The final preparation was homogeneous by the criteria of polyacrylamide-gel electrophoresis. Immunological evidence for purity could be given by double diffusion according to Ouchterlony. However, following gel isoelectric focusing highly purified SHBG displayed four different bands, as could be demonstrated by staining as well as by a photoscan of the [3H]5alpha-dihydrotestosterone-SHBG complex. After incubation with neuraminidase the microheterogeneity of SHBG disappeared and the asialo-SHBG showed only one band.

Chromatography, Gel↗
PubMed1978

The determination of 5alpha-androstane-3alpha, 17beta-diol in human plasma by radioimmunoassay.

Antibodies have been raised in rabbits against 3alpha, 17beta-dihydroxy-5alpha-androstane-6-0-carboxymethyloxime coupled with Cohn's fraction IV-4. The antiserum exhibited significant cross reactions with 5beta-androstane-3alph1, 17beta-diol, 5alpha-dihydrotestosterone, and testosterone. No cross reactions were observed with 5alpha-androstane-3beta,17beta-diol and 5-androstene-3beta,17beta-diol. The methodological criteria for the measurement of 5alpha-androstane-3alpha, 17beta-diol in human plasma were as follows: The specificity was ensured by separating the cross reacting steroids by thin layer chromatography. The intraassay and interassay coefficients of variation were found to be 6.2 and 10.2%, respectively. The sensitivity was 30 pg. The recovery of different amounts of 5alpha-androstane-3alpha,17beta-diol added to human plasma (80, 120, and 200 pg) yielded 91.3, 92.5, and 93.5%, respectively. The following concentrations of 5alpha-androstane-3alpha,17beta-diol have been determined in human plasma (mean +/- SD, ng/dl): Normal males: 18.98 +/- 5.9; normal females: 2.65 +/- 0.27; females with idiopathic hirsutism: 11.9 +/- 6.4; prepubertal children: not detectable.

Adolescent↗
PubMed1976

A simple radioimmunoassay for the measurement of testosterone glucosiduronate in unextracted urine.

A simple, reliable and rapid radioimmunoassay (RIA) for the determination of testosterone glucosiduronate (TG) in crude urine is described. Two protein-TG complexes were investigated in raising antibodies: a) Bovine serum albumin (BSA)-TG and b) human plasma Cohn's fraction IV-4 (CF)-TG. In rabbits, high titers of antibodies were obtained after the injection of CF-TG. The specificity of the antiserum was sufficiently high (cross reaction with free testosterone 27%, with 5alpha-dihydrotestosterone-glucosiduronate 20%). TG was estimated in small aliquots of male and female urine after evaporation overnight at 50 degrees C in order to eliminate interfering material. The intraassay coefficient of variation (CV) was found to be 6% and the interassay CV 11%. TB has been determined in 40 samples of urine simultaneously by "direct" RIA and by a "classical" RIA following hydrolysis with beta-glucuronidase. The coefficient of correlation was found to be 0.89. The mean excretion of TG in the urine of 26 healthy men amounted to 164+/-51 mug/24 hours with a range from 97 to 346 mug/24 hours. In a group of 16 women a mean urinary excretion of TG of 24+/-10 mug/24 hours was determined. The method allows a technician to assay 40 samples per day.

Antibody Specificity↗
PubMed1975

Reaction of poliovirus RNAs with antibodies to double-stranded RNA demonstrated by an immunochemical binding assay.

An immunochemical binding assay was used to investigate the reactivity of radioactively labeled viral RNAs from poliovirus-infected cells with antibodies to the synthetic double-stranded RNA, poly(I)-poly(C). A RNase-free antibody-containing serum fraction was employed. Poliovirus replicative form reacted with the antibodies to poly(I)-poly(C) as well as or better than poly(I)-poly(C). Poliovirus replicative intermediate reacted with the antibodies to a greater extent than poliovirus single-stranded RNA, but both were less reactive than replicative form. The use of the immunochemical binding assay with sucrose-gradient fractions demonstrated that for both poliovirus single-stranded RNA and replicative form the peak of reactivity with the antibodies was coincident with the peak of radioactive material precipitated by trichloroacetic acid. The proportion of replicative intermediate that reacted with the antibody increased in sucrose-gradient fractions containing the more slowly sedimenting RI RNA.

Animals↗