Search PubMed⌕ Search

Biomedical subjects

B Hudson

Publications and source records attributed to B Hudson.

At least 127 records · Page 7Linked to original sources
PubMed1983

Treatment of sperm autoimmunity in men.

Positive sperm immobilization tests were found in the sera of 6.3% of 491 infertile men. There was a higher frequency of family histories of autoimmune diseases than for other subfertile men. Prognosis for fertility was related to results of sperm-mucus penetration tests: progressively motile sperm indicated a fair outlook--8 of 15 couples conceived within 7 months either spontaneously or with artificial insemination with husband's semen. Absence of progressively motile sperm indicated severe infertility - only 6 of 72 couples produced pregnancies. Treatment of the latter group by temporary suppression of spermatogenesis with testosterone or with Artificial Insemination by Husband (AIH) appeared to be ineffective. However, sperm immobilization titres fell and sperm concentrations, motility and mucus penetration increased during treatment of 14 of the men with prednisolone (0.5-0.75 mg/kg per day) for 4-7 months and there were three pregnancies. It is concluded that sperm autoimmunity in men causing failure of sperm to penetrate cervical mucus produces severe but not absolute infertility. Immunosuppression with continuous high dose glucocorticoid reduces antibody levels and improves semen quality. A controlled trial is needed to determine if this treatment is a practical method for improving fertility in men with sperm autoimmunity.

Adult↗
PubMed1982

Effect of stress on steroid hormone levels in racehorses.

Cortisol and testosterone were measured by radioimmunoassay in plasma samples from race horses. None of 6 stressed male horses had low cortisol levels but testosterone levels (0.81 +/- 0.15 nmol/l) were significantly lower than in healthy horses (1.86 +/- 0.31 nmol/l). The conclusion was made that adrenocortical insufficiency is not a common association of stress in race horses. The reduction in testosterone levels is probably a nonspecific response similar to that seen in other species.

Adrenal Insufficiency↗
PubMed1982

Gonadotrophin releasing hormone causes a biphasic secretion of luteinizing hormone and follicle stimulating hormone by cultures of rat anterior pituitary cells.

Primary monolayer cultures of adult male rat anterior pituitary cells secreted both LH and FSH in a biphasic manner when incubated with gonadotrophin releasing hormone (GnRH). The peaks of secretion of LH and FSH were coincident: the first occurred between 15 and 30 min and the second between 1 and 3 h after the addition of GnRH. Approximately 20% of the total amount of gonadotrophins secreted in the 6 h treatment with GnRH was contained in the first peak. Inhibitors of the secretion of gonadotrophins affected LH and FSH secretion differently. Inhibin suppressed the secretion of FSH to a greater extent than that of LH, whereas testosterone and cycloheximide had a greater effect on LH. Neither phase of secretion of LH or FSH was reduced preferentially by inhibin or testosterone but the greater effect of cycloheximide was on the second phase of secretion.

Animals↗
PubMed1981

Effects of preceding androgen therapy on testicular response to human pituitary gonadotropin in hypogonadotropic hypogonadism: a study of three patients.

There is some uncertainty about the choice of initial therapy to induce virilization in men with hypogonadotropic hypogonadism (HH) who may subsequently desire fertility. Three patients with HH and azoospermia are described. All had received long-term androgen therapy in fully virilizing doses, and two also received interval androgen therapy. Spermatogenesis occurred in all three patients after treatment with human chorionic gonadotropin and human pituitary gonadotropin, and the wives of all three conceived. For two patients conception occurred three times in response to gonadotropin therapy, and libido and potency were maintained with testosterone between each conception. It is concluded that preceding long-term therapeutic doses of androgen do not impair subsequent induction of spermatogenesis in patients with HH.

Adult↗
PubMed1981

Reversible male infertility due to congenital adrenal hyperplasia.

We have studied a patient who was azoospermic and infertile. The cause of his infertility was unusual and curable: untreated congenital adrenal hyperplasia resulting from a partial 21-hydroxylase deficiency. The diagnosis was suggested by the combination of small testes, elevated levels of testosterone and suppressed levels of gonadotrophins.

Adrenal Hyperplasia, Congenital↗
PubMed1980

Photochemical dimerization of parinaric acid in lipid bilayers.

Parinaric acid (9,11,13,15-octadecatetraenoic acid), a conjugated tetraene fatty acid, undergoes a second-order photochemical reaction in phospholipid bilayers. The reaction results in the loss of the characteristic absorption of this chromophore and the development of new absorption demonstrating the presence of a triene chromophore. The progress of this reaction is easily monitored by measurement of the decrease in the fluorescence intensity from a uniformly illuminated sample. The reaction rate measured in this way is sensitive to the thermal phase transition of the bilayer and to the presence of cholesterol. The relationship of the second-order rate constant to the lipid diffusion coefficient is discussed. This relationship differs from that previously used for the analysis of similar photochemical processes.

Journal Article↗
PubMed1980

Effect of parental head circumference on that of the newborn child.

The head circumferences of 74 term, normal babies were measured, together with the head circumferences of their parents. Maternal head circumference had a significant effect on that of the newborn infant but paternal head circumference had not. An equation is given for estimating the expected head circumference of a newborn infant, provided the birthweight and maternal head circumference are known.

Birth Weight↗
PubMed1980

Prolonged biphasic response of plasma testosterone to single intramuscular injections of human chorionic gonadotropin.

The response of plasma testosterone to varying doses of hCG (0--6000 IU) given as a single im injection has been evaluated in normal men. After an initial rise at 2 h, the levels of testosterone demonstrated a secondary rise, reaching a peak 48 h after the im injection. The magnitude of the response varied directly with the dose of hCG used, and at the highest dose (6000 IU) testosterone levels were still elevated 6 days after administration. Plasma estradiol levels showed a dose-dependent rise, with peak levels being attained 24 h after hCG. The prolonged response of plasma testosterone to a single injection of hCG should prompt a reevaluation of diagnostic and therapeutic regimens using this agent.

Adult↗
PubMed1979

A bioassay for inhibin using pituitary cell cultures.

A bioassay for inhibin based on the suppression of gonadotrophin releasing hormone (Gn-RH)-stimulated secretion of FSH by primary monolayer cultures of rat anterior pituitary cells is described. The cultures were exposed to standard or test materials for 3 days. The levels of FSH in the media were measured by radioimmunoassay after exposure for 6 h to a maximally stimulating concentration of Gn-RH (10 nmol/l). The standard was prepared from ovine testicular lymph. Several preparations of proteins from gonadal tissues or secretions suppressed the levels of FSH in parallel with the standard. The levels of LH were also reduced but higher doses of active material were required. Non-specificity from cell damage and inactivation of Gn-RH have been excluded. The secretion of gonadotrophins by the pituitary cells was also inhibited by androgens, but not in parallel with the standard and secretion of LH was affected more than that of FSH. Control lymph protein preparations from castrated sheep had no detectable activity. The assay was sensitive and had adequate precision and practicability. It has proved useful for monitoring preliminary steps in the purification of inhibin.

Animals↗
PubMed1978

Clinical features and plasma hormone levels after surgical menopause.

This study reports the plasma levels of follicle stimulating hormone, luteinising hormone, oestradiol and testosterone in 43 women who had undergone bilateral oöphorectomy. Age was the only variable of those investigated which appeared to influence a hormone level; testosterone levels were found to decrease with increasing age. Two significant associations were found between clinical features of the menopause and the plasma hormone levels measured. Low levels of oestradiol were associated with pruritus vulvae and high levels of testerone were associated with headaches.

Adult↗
PubMed1978

Inhibin from cultures of rat seminiferous tubules.

Medium from cultures of mature rat seminiferous tubules contained a substance which suppressed, in a dose-related manner, the luteinizing hormone releasing hormone (LH-RH)-stimulated secretion of FSH by cultured rat pituitary cells. The secretion of LH was suppressed to a lesser extent and the basal secretion of both LH and FSH was inconsistently affected. Gel filtration on Sephadex G-100 did not fractionate the activity. The active material did not inhibit the secretion of TSH or destroy LH-RH and the activity was not due to testosterone or oestradiol in the medium. Control media from liver cultures were inactive. It is concluded that inhibin is present in media from cultures of rat seminiferous tubules.

Animals↗