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Biomedical subjects

F C Wu

Publications and source records attributed to F C Wu.

107 records · Page 6Linked to original sources
PubMed1982

The behavioural effects of testosterone undecanoate in adult men with Klinefelter's syndrome: a controlled study.

The behavioural effects of exogenous testosterone in men with marginally low circulating androgen levels were investigated. Four adult men with Klinefelter's syndrome, low normal testosterone levels and normal sexual activity and interest were given testosterone undecanoate (TU 160 mg daily by mouth; Organon International) and placebo using a double blind cross-over design. A modest increase in sexual interest was observed during TU administration compared to placebo, though there were no effects on self-reported mood or energy, or on erectile responsiveness in the laboratory. Increase in circulating hormone levels during TU administration was more marked for DHT than for testosterone. The possible implications of this are discussed.

Adult↗
PubMed1982

Raised plasma oestrogens in infertile men with elevated levels of FSH.

In twenty oligospermic or azoospermic patients with elevated plasma FSH, the mean concentrations of plasma oestrone sulphate (843 +/- 233 pg/ml), oestrone (54 +/- 10.4 pg/ml) and oestradiol (46.6 +/- 12.6 pg/ml) were found to be significantly higher than in twenty-one normal fertile men of comparable age (593 +/- 220 pg/ml, 40.6 +/- 8.8 pg/ml and 33.1 +/- 10.9 pg/ml respectively). SHBG binding capacity was elevated in the infertile group (infertile 3.35 +/- 0.82 x 10(-8) M/l v. normal 2.76 +/- 0.89 x 10(-8) M/l) but the total plasma testosterone concentrations were comparable (infertile 5435 +/- 1578 pg/ml v. normal 5046 +/- 1102 pg/ml). Evidence was cited to support the view that Sertoli cells, in response to an unphysiological FSH stimulation, are a likely source of excessive oestrogen production. The possible significance of increased intra-testicular and circulating oestrogen in the altered state of testicular steroidogenic function in men with primary seminiferous tubular defects was discussed.

Adult↗
PubMed1982

The clinical features of diabetic impotence: a preliminary study.

Twenty-seven diabetic men with erectile impotence were given physical and psychosexual assessments. Physical assessment included vascular and neurological evaluation. Psychosexual assessment was by means of a semi-structured interview. Seven potent diabetic men formed a control group. Patients with erectile failure had a varied clinical picture which differed from the stereotype of diabetic impotence: morning erections were preserved in over a half (55 per cent), eight patients (30 per cent) had intact spontaneous erections, and sexual interest was reduced in 12 patients (44 per cent). In 13 patients (48 per cent) ejaculation was disturbed and a further four patients (15 per cent) described unusual disorders of sexual function. Within the group there were no differences in clinical picture between those with and without autonomic neuropathy, retinopathy or potential psychogenic factors.

Adult↗
PubMed1982

Human testis does not secrete oestrone sulphate.

The concentrations of five steroids in samples of spermatic venous blood collected from 17 men undergoing ligation of varicocoeles were compared with those in samples from the antecubital vein. There was evidence of testicular secretion of testosterone, androstenedione, oestradiol-17 beta and oestrone, since the ratios of the mean concentrations in spermatic venous plasma to those in peripheral venous plasma were 77.2, 9.1, 28.7 and 1.6 respectively. The testicular secretion of oestrone sulphate was minimal; the ratio of the mean concentrations in spermatic and peripheral plasma was 1.07. These results support the view derived from isotope dilution studies that almost all oestrone and oestrone sulphate in the circulation is derived from peripheral conversion of other precursor steroids.

Adolescent↗
PubMed1981

Endocrine assessment of the subfertile male.

Sixty-three male (XY) patients attending a subfertility clinic with average sperm density under 40 million/ml were studied by testicular biopsy and multiple basal estimations of plasma LH, FSH, testosterone as well as LHRH (50 micrograms i.v.) stimulation. A further forty patients with similar sperm densities also had testicular biopsy but only single estimations of the three hormones. A single basal FSH was found to be the best discriminator of testicular histologies. Patients with testicular biopsies showing germ cell aplasia in some or all seminiferous tubules (grades 3 and 4) had significantly higher basal FSH than those with hypospermatogenesis, germ cell arrest or normal appearance (grades 1 and 2). Basal FSH also showed a linear trend rising with decreasing sperm density but only rose above the normal range when sperm densities fell below 1 million/ml. When basal FSH, testicular histology and sperm density were considered together in the whole group (n = 100), high levels of FSH accurately indicated the presence of germ cell aplasia in some or all seminiferous tubules in azoo- and oligospermic men with sperm density under 5 million/ml. Normal FSH and azoospermia is diagnostic of obstruction in the excurrent ducts, and further investigation is undertaken if surgical correction of the obstruction is contemplated. Hormone estimations are not helpful in oligospermic patients with average sperm density over 5 million/ml. On the basis of these findings it is suggested that there is little place for the LHRH test in the routine assessment of male subfertility. Testicular biopsy is indicated only in oligospermic patients with average sperm density under 5 million/ml and normal basal FSH.

Adult↗
PubMed1980

Diabetic impotence.

Explore the source record for details and available documents.

Diabetes Complications↗
PubMed1980

The prevalence of diabetic impotence.

In a survey of 541 diabetic males, aged 20-59 years, 190 (35%) had erectile impotence. Using linear logistic regression models for analysis the five most significant associations with impotence were age (p < 0.001), treatment with either insulin or oral hypoglycaemic agents (p < 0.001), retinopathy (p < 0.001), symptomatic peripheral neuropathy (p < 0.001) and symptomatic autonomic neuropathy (p < 0.005). The greatest correlations were found in patients with severe microangiopathy, as demonstrated by proliferative retinopathy and symptomatic autonomic neuropathy. In addition the duration of diabetes and the presence of ischaemic heart disease, nephropathy and poor diabetic control may also be associated with diabetic impotence. It is concluded that diabetic impotence is still a common problem and may have a multifactorial aetiology.

Adult↗
PubMed1980

Binding of human chorionic gonadotrophin to testicular biopsy tissue from infertile men and the effect of prior treatment with human chorionic gonadotrophin.

The binding of 125I-labelled human chorionic gonadotrophin (HCG) to testicular tissue obtained by biopsy from 27 infertile men has been investigated. Fresh tissue cut into pieces was used for these studies as homogenization and/or freezing severely reduced the ability of testicular tissue to bind HCG. In five infertile men who had a normal endocrine profile and normal testicular histology, 10.3 +/- 1.4 (S.D.) pg 125I-labelled HCG were bound/mg testis, which was similar to binding (7.9 +/- 3.6 pg/mg) to testicular tissue obtained from three apparently normal men who underwent orchidectomy for prostatic carcinoma. However, in five infertile men with germ cell aplasia binding was increased to 16.6 +/- 5.7 pg/mg tissue. Fourteen infertile men were injected 24 h before biopsy with HCG, and this treatment consistently, and in most cases significantly, reduced the testicular binding of 125I-labelled HCG compared with that found in untreated, infertile men. It was concluded that measurement of HCG-binding in testicular biopsy specimens is feasible and may prove useful in assessing similarities between Leydig cell function in man and animals.

Adult↗
PubMed1977

Peripheral blood leucocytes in thyrotoxicosis (Graves' disease) as studied by conventional light microscopy.

Peripheral blood leucocyte counts in 104 thyrotoxic (Graves' disease) patients were compared with those in 107 normal subjects of similar age and sex. The thyrotoxic patients had a significant leucopenia with an absolute and relative neutropenia. They also had a relative lymphocytosis but the absolute lymphocyte count was within normal limits. The relative and absolute monocyte counts were normal.

Adolescent↗
PubMed1975

The nonhistone chromosomal proteins of vertebrate liver and kidney: a comparative study by gel electrophoresis.

The nonhistone chromosomal proteins (NHC proteins) probably include enzymes of chromosomal metabolism, general structural proteins, and possibly control elements. In theory, these proteins may have been strongly conserved during evolution, as the histones have. We have used sodium dodecyl sulfate (SDS) disc gel electrophoresis to analyze and compare the NHC proteins of two tissues, liver and kidney, from rat, cat, cow, chicken, turtle, and frog. The gel patterns indicate that the NHC proteins have changed much more during evolution than have the histones; the total pattern of NHC proteins has not been conserved. However, there does appear to be a conservation of a subset of bands for each tissue investigated. Further chemical analysis will be required to establish the significance of the results.

Animals↗
PubMedDate not supplied

Analysis of the relationship between defective sperm function and the generation of reactive oxygen species in cases of oligozoospermia.

The ability of human spermatozoa to exhibit sperm-oocyte fusion in response to the ionophore, A23187, was examined in relation to the capacity of these cells to generate reactive oxygen species. In 70 fertile control donors, there was an overwhelming pattern of high levels of sperm-oocyte fusion associated with low levels of reactive oxygen species production. By contrast, 88% of the 74 oligozoospermic patients exhibited less than 25% oocyte penetration in response to A23187 and 58% exhibited no penetration whatsoever. Of the 40 oligozoospermic patients who failed to respond to A23187, nine had low levels of reactive oxygen species production in association with impaired liquefaction of seminal plasma. Of the remainder, 17 (55%) exhibited defective sperm function together with elevated production of reactive oxygen species. These observations, which are the first to describe a biochemical defect in the spermatozoa of oligozoospermic patients, may carry significant implications for the etiology and treatment of this condition.

Calcimycin↗
PubMedDate not supplied

Energy metabolism during male human puberty. I. Changes in energy expenditure during the onset of puberty in boys.

In order to identify metabolic cues involved in the control of onset of male human puberty, 70 pre- and peri-pubertal boys, aged 9.21 +/- 0.03 years at the start of the study, had their lean body mass (LBM), basal metabolic rate (BMR) and total daily energy expenditure (TDEE) measured at 6-monthly intervals on three occasions each. Hormonal pubertal activity was assessed by measuring early morning salivary testosterone (ST) at each assessment. A subgroup of 44 boys, who first showed an increase in ST at their third assessment, was identified. In the general population at this stage of development, and in the overall 70 boys studied here, BMR/LBM decreases significantly with age (from 0.185 +/- 0.001 to 0.180 +/- 0.001 MJ/day per kg over 6 months, p < 0.01, ANOVA), since both are increasing, but LBM at a greater rate than BMR. The 'imminently pubertal' group of 44 boys showed no decrease in the ratio BMR/LBM (0.182 +/- 0.001 MJ/day per kg) during the 6 months between their first two assessments despite the normal increase in LBM, indicating that BMR rises at a similar rate to LBM during this specific period of development. This observation supports the hypothesis that energy balance plays an important role during the events leading up to the onset of puberty and subsequent fertility.

Adolescent↗
PubMedDate not supplied

Energy metabolism during male human puberty. II. Use of testicular size in predictive equations for basal metabolic rate.

This study tests the hypothesis that equations to predict basal metabolic rate (BMR) of adolescent boys may be made more accurate by using a measure of pubertal maturity (testicular volume, TV). Eighty-six male volunteers aged 11.8-13.7 years were studied. There was a wide range of pubertal development within the subject group, ranging from mean TV of 3 to 22.5 ml. BMR was found to correlate more highly with TV (r = 0.519) than height (r = 0.425) or age (r = 0.272). BMR predicted using the World Health Organization equations (based on height and weight) were significantly higher than measured BMR in early pubertal boys (TV < or = 4 ml, BMR (measured) = 5.04 +/- 0.17, BMR (predicted) = 6.14 +/- 0.15 MJ/day, p < 0.001, Student's t-test). The results provide evidence that measurement of testicular volume may increase the accuracy of equations for the prediction of BMR of adolescent boys.

Adolescent↗
PubMedDate not supplied

Comparison between testosterone enanthate-induced azoospermia and oligozoospermia in a male contraceptive study. V. Localization of higher 5 alpha-reductase activity to the reproductive tract in oligozoospermic men administered supraphysiological doses of testosterone.

Sex steroid contraceptive regimes result in incomplete suppression of spermatogenesis in 30-45% of Caucasian men. The basis for this is unclear, but differences in the activity of 5 alpha-reductase (5 alpha R) have been demonstrated. Two isoforms of 5 alpha R have been described: 5 alpha R1 is found in skin, whereas the predominant from in reproductive tissues is 5 alpha R2. To investigate possible contributions of these isoenzymes, we have investigated androgen-dependent changes in seminal plasma androgens (5 alpha R2) and sebum production (5 alpha 1) during administration of a supraphysiological dose (200 mg IM weekly) of testosterone enanthate (TE) to 33 normal men. Eighteen men rapidly (< 20 weeks treatment) became azoospermic, the remainder having a mean sperm density of 2.0 +/- 0.6 x 10(6) at that time. The concentrations of testosterone and 3 alpha, 17 beta-androstanediol glucuronide (AdiolG) were lower in seminal plasma than in blood but rose by a similar degree (100%) after 16 weeks TE treatment in both groups. There were no differences in seminal-plasma concentration of testosterone or AdiolG between azoospermic and oligozoospermic responders, either pretreatment or after 16 weeks TE treatment. Although the concentrations of dihydrotestosterone (DHT) were similar in seminal plasma and blood pre- and posttreatment, there was a selective increase in seminal plasma DHT concentration in the oligozoospermic responders from 2.12 +/- 0.29 to 2.94 +/- 0.33 nmol/L (P < 0.05), while there was no significant change in the azoospermic responders (2.18 +/- 0.31-2.54 +/- 0.27 nmol/L) after 16 weeks of TE treatment. Dihydrotestosterone in seminal plasma is primarily derived from 5 alpha R activity in the epididymis. The concentration of prostaglandin E2 (PGE2) in seminal plasma was unchanged during TE treatment. Sebum excretion was increased during TE treatment, but there were no difference between azoospermic and oligozoospermic responders pretreatment or after 16 weeks TE treatment. These results are consistent with the hypothesis that incomplete suppression of spermatogenesis during TE treatment is associated with a relatively higher 5 alpha R activity in the reproductive tract (epididymis and/or testis) during TE treatment. As the predominant form of 5 alpha R in the reproductive tract is 5 alpha R2 (type 2), we conclude that the increase in activity derives from this form of the enzyme, rather than the type 1 form (5 alpha R1) predominantly found in nongenital skin.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗