A Quantitative Structural Model of the Testis of Fertile Males with Normal Sperm Counts

The morphology of testicular biopsies of 8 healthy fertile men with proven normal sperm counts was studied using stereological techniques. Quantitative estimations were made of different cellular compartments in the testicular biopsies. The experimental errors of observation, homogeneity of the section, accuracy of the measurements and errors caused during the preparation of the sections were studied. A stereological model of the human testis comprising all compartments was designed. The present observations on the stereological parameters were compared with the results in literature; generally a good agreement was found.
This stereological model enabled the authors to establish the quantitative correlations that exist between the separate compartments of the human testis. The tubular length density was positively correlated with the tubular surface density. The tubular surface density showed a negative correlation with the volume density of the germinal cell nuclei. The tubular volume density showed a negative correlation with the volume density of the Leydig cells. The intra-tubular volume density correlated negatively with the volume density of the Leydig cells and with the volume density of the remaining extra-tubular tissue. The intra-tubular tissue density correlated negatively with the volume density of the intra-tubular space.     

Correlations between the Quantitative Morphology of the Human Testis and Sperm Production The Testis of Healthy Men with Normal Sperm Counts

Stereology was used as a morphometric method to study the testicular biopsies of 8 healthy volunteers with a proven fertility and normal sperm counts.
The geometrical mean of the sperm density and total sperm count of 2 semen samples were correlated with the measured and calculated stereological parameters. The volume density of the germinal cell nuclei ( r = 0.72) and the intra-tubular tissue volume density ( r = 0.81) were significantly correlated with the sperm density. A significant correlation was demonstrated between the total sperm count and the volume density of the germinal cell nuclei ( r = 0.71) and the volume density of the Leydig cells ( r =–0.70).
Using stepwise multiple regression analysis the prediction of the observed variance of the log sperm density was feasible ( r = 0.996; P = 0.0007) with 4 stereological parameters: the volume density of the germinal cell nuclei (positive correlation), the volume density of the tubular wall (negative correlation), the volume density of the Leydig cells (negative correlation) and the tubular surface density (positive correlation).
The observed variance of the log total sperm count was predicted ( r = 0.96; P = 0.003) with 3 stereological parameters: the volume density of the germinal cell nuclei (positive correlation), the volume density of the Leydig cells (negative correlation) and the volume density of the blood vessels (negative correlation).     

Serum apolipoproteins A-I and B in male and female full-term new borns of the Toledo study (Spain)

Cord serum apolipoproteins (Apo) A-I and B from 548 healthy, full-term singletons were studied. Females displayed slightly, but significantly, higher Apo A-I levels ( p < 0.001) than males. Particularly at weeks 38 and 39 ( p < 0.05), whereas Apo B was not gender affected but likewise increased ( p < 0.05) between weeks 37 and 41. Apo A-I values increased ( p < 0.05) with gestational age in males, but with birthweight in females. Results suggest that small gender and age-related metabolic differences exist at birth in terms infants     

Morphology of draining lymph nodes after local immune stimulation with C. parvum: comparison of pelvic nodes in carcinoma of cervix and popliteal and inguinal nodes of guinea-pig.

Morphological changes are described in pelvic lymph nodes excised 10 days after C. parvum (CP) treatment of patients with cervical carcinoma. Guinea-pig popliteal and inguinal lymph nodes were investigated from Days 1 to 10 after an injection of 70 micrograms CP into the footpad. Eosinophils were detected from the first few hours after stimulation, initially in the marginal sinus, then in the medullary sinuses and subsequently in the efferent lymphatics. From Day 2 to Day 6, histiocyte accumulations with the appearance of epithelioid cells were found mainly in subcapsular and interfollicular areas, and small granulomas were also seen in the paracortex. The granuloma formation in the lymph node was considered as an indication of the activation of histiocytes. Besides small granulomas in the paracortex, activated interdigitating cells, surrounded by scattered lymphoblasts and eosinophils, were also present. We considered this lymphoblastic response and eosinophilic accumulation as likely to be due to blastogenic factor and eosinophil stimulation promotor. Eight to 10 days after CP stimulation, the macrophage lymphoblast eosinophil response was replaced by a B-cell reaction: germinal-centre activation and medullary plasma cells. Such a B-cell reaction was also found in the human pelvic nodes removed at operation, but this reaction could not be attributed to CP treatment alone, since cervical-carcinoma patients not treated with CP also showed such reactions. In contrast, pelvic lymph nodes removed at necropsy from females killed in traffic accidents showed no predominance of either B- or T-cell stimulation.     

Posterior spinal cord block: a dosimetric study

To determine the optimal width of a midline posterior spinal block (MPSB) (to avoid delivering too great a dose to the cord and too small a dose to adjacent tissue), the authors determined with magnetic resonance (MR) imaging normal ranges of cord depth and width and correlated them with film dosimetric data. In 59 randomly selected patients there was a wide range for both depth and width. The average depths of the anterior and posterior surfaces of the cord were 6.7 cm +/- 1.4 and 5.4 cm +/- 1.3, respectively. The average cord width was 1.6 cm +/- 0.4. Optimal cord block width as a function of cord width was determined for a 6-MV photon beam. The optimal cord block width at the surface (half-value layer [HVL] thickness = 6) varied from 1.5 to 3.0 cm for cord widths of 0.8-2.4 cm, which correspond to two standard deviations from the average. There was no significant dependence on depth of the cord. For optimal treatment outcome, the MPSB width may have to be determined for each patient individually.