Biomedical subjects

M M Buchholz

Publications and source records attributed to M M Buchholz.

3 recordsLinked to original sources

PubMed2000

hCGbeta core fragment is a metabolite of hCG: evidence from infusion of recombinant hCG.

The availability of recombinant human chorionic gonadotrophin (r-hCG) has allowed us to measure its metabolic and renal clearance rates and to study the origin of the beta core fragment of hCG (hCGbetacf). Serum and urine samples were collected from six subjects, after an intravenous injection of 2 mg (equivalent to 44 000 IU Urinary hCG) r-hCG, and assayed for hCG and the beta subunit (hCGbeta). Urine from four of the subjects was also subjected to gel chromatography and assayed for hCGbetacf and hCG. r-hCG, administered as an intravenous dose, was distributed, initially in a volume of 3.4+/-0.7 l (mean+/-s.d.) and then in 6.5+/-1.15 l at steady-state. The disappearance of r-hCG from serum was bi-exponential, with an initial half-life of 4.5+/-0.7 h and a terminal half-life of 29.0+/-4.6 h. The mean residence time was 28. 6+/- 3.6 h and the total systemic clearance rate of r-hCG was 226+/-18 ml/h. The renal clearance rate was 28.75+/-6.2 ml/h (mean+/-s.d). hCGbetacf was detected in all urine samples collected at 6 h intervals. Over the 138 h period of urine collection, 12.9% (range 10.1-17.3% ) of r-hCG injected was recovered as the intact molecule and 1.7% (range 0.8-2.9%) was recovered as the hCGbetacf, in 4 subjects. The molar ratio of hCGbetacf to hCG in urine increased from 3.1+/-1.7%, on day 1, to 76+/-34.3% (mean+/-s.e.m.) on day 5, after r-hCG infusion, suggesting that hCGbetacf is a metabolic product of the infused r-hCG.

Adolescent↗

PubMed1994

Post-orchiectomy hot flushes.

Orchiectomy is a frequently performed androgen ablative therapy in men with prostatic cancer. Sudden withdrawal of sex steroids in men can lead to troublesome menopausal symptoms such as hot flushes (HF) and profuse sweating. In the past, HF in men have received little attention and therapeutic options are not widely known. HF are a side effect of orchiectomy and other androgen ablative therapies and can no longer be neglected. The considerable decrease in quality of life caused by HF is particularly hard on patients who are dependent on palliative treatment. Because most patients will seek palliation, it is important that medical practitioners be made aware of the etiology and treatment of HF. In this article the frequency and intensity of HF in 32 patients were studied and present-day treatment options are summarized.

Aged↗

PubMed1992

Testicular dysplasia causing disturbance of spermiogenesis in patients with unilateral torsion of the testis.

Fifty-five patients were followed up for their state of fertility at a time varying in length after testicular torsion. In addition to the spermiogram they were screened for sperm antibodies. Biopsy samples were collected from the contralateral (not contorted) testis in 34 patients at the time of torsion or immediately afterwards. Two to 8 years after torsion only 7 out of 55 patients had a normal spermiogram. Nineteen had an OAT syndrome, 10 had asthenospermia and 19 had teratospermia. Sperm antibodies occurred very rarely at the time of torsion (2/36) or at the time of a further checkup (2/36). Immunological damage to the noncontorted testis by the contorted one seems therefore rather unlikely. Histology of the contralateral testis, the samples of which were taken at the time of torsion (30) or up to 4 months later (4), showed pathological conditions in 30/34 cases (desquamation of the germinative epithelium, atrophy of the Leydig cells, malformation of spermatoblasts) and normal spermiogenesis in 4 cases only. Hence, a preexistent congenital testicular dysplasia must be assumed to be the cause of the observed disturbance of spermiogenesis and reduced fertility.

Adult↗