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L I Lipshultz

Publications and source records attributed to L I Lipshultz.

139 records · Page 8Linked to original sources
PubMed1977

Androgen-binding activity in the human testis and epididymis.

The quantitation of androgen-binding activity in human testes, epididymides, and serum is reported and compared with that of similar tissue in the rat. By using steady-state polyacrylamide gel electrophoresis and a tritiated 0.5 nM testosterone label, values for specific binding activity, reported as picomoles per milligram of protein, were found to be 0.21 +/- 0.01 in normal human, epididymides, 0.03 in testes, and 0.44 +/- 0.07 in human serum. Tissues from men receiving exogenous estrogen were also similarly analyzed and found to possess significantly higher androgen-binding activity: 4.10 +/- 0.48 pmoles/mg of protein (epididymides), 4.01 (testes), and 5.63 +/- 1.15 (serum). Since man possesses a sex steroid-binding globulin, attempts were made to differentiate Ion-exchange chromatography, steroid specificity, and dissociation half-time determinations were suggestive but did not conclusively demonstrate the existence of two distinctly different androgen transport macromolecules in man.

Androgens↗
PubMed1976

Testicular function after orchiopexy for unilaterally undescended testis.

Testicular function was determined in 29 men, 21 to 35 years old, who had undergone orchiopexy for unilaterally undescended testis at four to 12 years of age. Serum testosterone and dialyzable testosterone concentrations of these men were not significantly different from those of a control group of 30 normal men, and their basal serum luteinizing hormone concentrations and serum luteinizing hormone responses to synthetic gonadotropin-releasing hormone were only slightly higher than those of the normal men. The mean sperm density of the patients, however, was only one third of that of the normal men (p less than 0.001). The mean serum follicle stimulating hormone response ro gonadotropin-releasing hormone of the patients was doubled that of the normal men (p less than 0.001). The data indicate that spermatogenesis may be abnormal after orchipexy, and suggest that men with unilaterally undescended testis may have bilateral testicular abnormality.

Adult↗
PubMed1976

Cryptorchidism in the subfertile male.

Certain conclusions may be drawn from the present review and presentation of new data concerning the unilaterally cryptorchid patient and possible subfertility: 1. The truly undescended testis--not the retractile testis of infancy--will not descend spontaneously after 1 year of age. 2. The seminal quality of the unilaterally cryptorchid patient is definitely impaired, although not rendered infertile, in a great majority of patients irrespective of the time of surgery. 3. The dystopic position of the maldescended testis appears to superimpose a second insult on what very likely may be an inherent abnormality in the cryptorchid testis, the latter accounting, perhaps, for its abnormal extrascrotal position. 4. Orchiopexy before the age of 5 seems advisable to ensure minimal histologic changes that may be secondary to the testis' increased exposure to elevated extrascrotal temperature. 5. The cryptorchid testis will be smaller in size irrespective of surgery, and usually correlates with significant testicular pathology. 6. Basal levels of gonadotropins, especially follicle-stimulating hormone, are likely to be elevated, but this does not necessarily imply overwhelming testicular damage. Androgen production should not be affected. 7. Surgical correction is advised when human chorionic gonadotropin stimulation fails to produce teticular descent, thereby defining the maldescended testis as not merely retractile but truly "crytorchid."

Androgens↗
PubMedDate not supplied

Varicocele as a progressive lesion: positive effect of varicocele repair.

Varicoceles are the leading correctable cause of infertility in men who present to an infertility clinic for evaluation. Consequently, the surgical correction of a varicocele, known as a varicocelectomy, is the most commonly performed operation for the treatment of male infertility. The current data suggest that an individual with a varicocele, even with a previously normal semen analysis or documentation of previous fertility, is at risk for subsequent loss of testicular function and infertility. Many of these patients will need to be treated because there is convincing evidence that a varicocele may have a progressive toxic effect on the testes that may ultimately result in irreversible infertility if left untreated. Identifying those individuals with varicoceles that will ultimately cause fertility impairment is still beyond our current clinical capabilities. Current investigative modalities, e.g. semen analysis, testicular measurement, serum gonadotrophin determination, gonadotrophin-releasing hormone (GnRH) stimulation test, and testis biopsy analysis, may be employed to detect early changes in testicular physiology produced by a varicocele.

Hormones↗