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Biomedical subjects

D B Weiss

Publications and source records attributed to D B Weiss.

At least 37 records · Page 2Linked to original sources
PubMed1995

[Severity of testicular varicocele and sperm cell ultramorphologic characteristics].

Ultramorphologic characteristics of sperm cells found in infertile men with varicoceles were compared with the severity of the varicocele. Classification of varicoceles into mild, moderate or marked was determined by spermatic vein diameter and degree of blood reflux. These were evaluated by high resolution duplex sonography. There were no statistical differences between the 3 grades of varicocele severity with regard to abnormalities in the subcellular organelles of the acrosome, karyoplasm, and skeleton of spermatozoal heads, or in the axoneme, outer dense fiber and skeleton of sperm cell tails. The only abnormal ultramorphologic features found to be significant among the 3 groups were differences in the frequencies of karyoplasm agenesis, and of partial agenesis, malformation and degeneration of the acrosome in sperm cell heads. However, these features could not be related to grade of severity and therefore, no ultramorphologic severity pattern could be detected. Thus, no varicocele beneficial score based on grade of severity and sperm cell ultramorphology can be suggested for clinical use.

Humans↗
PubMed1994

[Epididymal fine needle aspiration replacing vasography].

Epididymal fine needle aspirations (EFNA) were performed on 29 epididymides of 17 infertile, azoospermic men in whom testicular cytology revealed adequate spermatogenesis. Sonograms confirmed the presence of all the excretory male organs. EFNA was performed to diagnose and locate the site of genital tract occlusion. The presence of cuboidal epithelial cells in the aspirate was the sole indication that epididymal content was aspirated. In 10 (34%) of the 29 aspirates there were only cuboidal epithelial cells and no spermatozoa, indicating proximal occlusion in the rete testis, in the canaliculi efferents or in the most proximal segment of the epididymis itself. Occlusion in the distal segments of the epididymis or in the vas deferens was diagnosed in 13 epididymal aspirates (45%) which contained both cuboidal cells and spermatozoa. In 6 epididymides (21%) no conclusion could be reached because of failed aspirations. There are a variety of treatment modalities available for male genital tract obstruction, such as reconstructive surgery or IVF. The success rate of treatment is mainly dependent on the site of obstruction. Since vasography has its own limitations and hazards, diagnostic EFNA should be performed before treatment in men in whom genital obstruction is suspected.

Biopsy, Needle↗
PubMed1993

Testicular fine needle aspiration as a diagnostic method.

We believe testicular FNA is a reliable, simple, and accurate method for the assessment of testicular pathology and can replace the biopsy. Only when insufficient conclusions may be drawn from the cytologic smears obtained is open biopsy indicated.

Adult↗
PubMed1982

Quantitative peritoneal lavage in the assessment of intraperitoneal inflammatory processes.

Quantitative peritoneal lavage in order to assess the volume of the intraperitoneal fluid was performed in 34 female patients with acute abdominal pain and signs of peritoneal irritation. The peritoneal lavage was done using the dye-dilution technique with Evans-Blue Human Serum Albumin Complex (EBA) as a marker. In 22 patients with intraperitoneal inflammatory process the mean volume of exudate in the peritoneal cavity was 585.1 ml while in patients without any intraperitoneal inflammatory process the mean volume of the intraperitoneal fluid was 128.7 ml. This difference between the volumes was statistically significant (p less than 0.05). It is felt that an intraperitoneal fluid volume of above 250 ml is a highly suggestive indicator of an intraperitoneal inflammatory process. A quantitative peritoneal lavage with EBA as a marker can therefore be used as a diagnostic tool in the evaluation of patients with acute abdominal pain.

Adolescent↗
PubMed1979

Leydig cell density and function and their relation to gonadotropins in infertile oligospermic men with varicocele.

Circulating gonadotropin and testosterone levels in infertile men with varicocele and sperm counts of less than 10(7)/ml were correlated with testicular Leydig cell density and in vitro testosterone synthesis. A significant correlation was found between Leydig cell density and both plasma testosterone levels and in vitro testosterone synthesis. Luteinizing hormone (LH) levels paralleled the in vitro testosterone synthesis. Although in the majority of patients, in vitro testosterone synthesis and Leydig cell density were low, plasma testosterone and LH levels were within the normal range. The only abnormal circulating hormonal level was high follicle-stimulating hormone in the most severely oligospermic patients. No difference were found between the right and left testes with regard to in vitro testosterone synthesis or Leydig cell density, and no correlation with patient age or site or degree of varicocele could be demonstrated. These findings suggest that Leydig cell dysfunction was the mechanism responsible for the oligospermia and infertility of these patients.

Adult↗
PubMed1978

Quantitation of Leydig cells in testicular biopsies of oligospermic men with varicocele.

Leydig cell density was evaluated quantitatively in bilateral testicular biopsies from 16 oligospermic men with varicocele. The method utilized for this quantitation is based on the determination of the total number of Leydig cells, Leydig cell clusters, and seminiferous tubules in the entire histologic section of each biopsy, and the calculation of the following indices: mean Leydig cells per seminiferous tubule, mean Leydig cell clusters per seminiferous tubule, and mean Leydig cells per cluster. A significant correlation between Leydig cells per tubule and Leydig cell clusters per tubule was demonstrated, suggesting that determination of Leydig cell clusters per seminiferous tubule in testicular biopsies is an objective and clinically applicable method for quantitative evaluation of Leydig cell density. An association of varicocele with Leydig cell hyperplasia was not noted for the 16 patients studied. In addition, no significant differences in Leydig cell density between right and left testes were found, and no correlation between Leydig cell density and site or degree of varicocele, or age of the patients could be demonstrated. To our knowledge this is the first report of quantitative analysis of Leydig cell density in men with varicocele.

Biopsy↗
PubMed1978

Quantitative analysis of the seminiferous epithelium in human testicular biopsies, and the relation of spermatogenesis to sperm density.

Quantitative analysis of the seminiferous epithelium was performed in bilateral testicular biopsy specimens from 14 patients with sperm counts ranging from 0 to 89 million/ml. All Sertoli cells and germ cells within each seminiferous tubule cross-section were counted in all biopsies. Results were expressed either as number of cells per unit length of seminiferous tubule circumference or as number of cells per Sertoli cell. Results were correlated with sperm count (millions per milliliter), total sperm count (millions per ejaculate), and age. A significant correlation between sperm density and germ cell counts was demonstrated. Coefficients of correlation were higher when results were expressed per unit of tubular wall length than when expressed per Sertoli cell. In men with sperm counts below 5 million/ml the number of germ cells in the biopsy was lower than in men with higher sperm counts. Spermiogenesis appeared to be most affected. In this group of patients an adverse effect of age on spermatogenesis was noted.

Adolescent↗
PubMed1978

A possible mechanism for the detrimental effect of varicocele on testicular function in man.

Seminiferous epithelium histology, Leydig cell density, and in vitro testosterone synthesis were quantitated in bilateral testicular biopsies from men with varying degrees of unilateral or bilateral varicoceles. Results were correlated with plasma levels of gonadotropins (follicle-stimulating hormone [FSH], luteinizing hormone [LH]) and testosterone (T), as well as with semen quality. In patients with bilateral varicoceles, spermatogenesis, Leydig cell density, plasma T levels, and in vitro T synthesis were significantly lower than in patients with unilateral varicoceles. Varicoceles appeared to affect maximally the latest stages of spermatogenesis. A negative correlation between FSH and LH levels and spermatogenesis was observed; however, a dissociation between the two gonadotropins occurred when spermatogenesis declined. Plasma T levels were within the normal range in all patients. The T:LH ratio was significantly correlated with spermatogenesis and sperm motility. Leydig cell density was abnormally low in oligospermic patients, and it was significantly correlated with in vitro T synthesis, spermatogenesis, sperm motility, and semen volume. Sperm count and motility were significantly correlated in this group of patients, suggesting a common pathophysiology for the effect of varicocele on spermatogenesis and sperm motility. This common pathophysiology appears to be disturbed Leydig cell function resulting in decreased testicular androgen production, in turn causing inadequate spermatogenesis and epididymal function.

Adolescent↗
PubMed1978

Suggestion of abnormal testicular steroidogenesis in some oligospermic men.

Androgen biosynthesis in the testis may be analyzed in some detail by means of techniques of in vitro incubation of small testicular biopsy specimens with suitable radiolabelled precursors. Sixty-six tissue specimens from 33 patients who underwent bilateral testicular biopsies because of infertility were incubated in vitro with [3H]pregnenolone in order to investigate the possibility of abnormalities in their steroid biosynthetic activity. As a normal control, testicular tissue obtained by testicular biopsy from a young normal volunteer was used. The distribution of metabolites in the incubates of testes from 8 infertile men differed greatly from the remaining 25 patients and the normal control. The major steroids formed from pregnenolone by the testes of those 8 men were 17-hydroxypregnenolone, dehydroepiandrosterone, 20alpha-dihydropregnenolone and and 20alpha-dihydro-17-hydroxypregnenolone. Very small amounts of delta4-3 oxo products (progesterone, 17-hydroxyprogesterone, androstenedione and testosterone) were formed suggesting a deficiency of 3beta-hydroxy-steroid-dehydrogenase activity in the testes of these 8 men, possibly related to the derangement of their spermatogenic function.

Adult↗