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Biomedical subjects

S J Samuels

Publications and source records attributed to S J Samuels.

78 records · Page 5Linked to original sources

Morphometric analysis of spermatozoa in the assessment of human male fertility.

A videomicrographic system was developed for measurement of morphometric parameters of human spermatozoa. Contours of the images of spermatozoa on a video monitor are digitized by manually tracing them with the cursor of an electromagnetic digitizer integrated to a microcomputer. The accuracy and precision of the methodology were evaluated. A comparison of human sperm heads in shallow wet preparations and in dried, stained preparations indicated that the latter were smaller in length, width, projected area, and circumference, but that the ratio length/width was not different. An analysis was made of 457 ejaculates from 16 fertile donors. The variation between ejaculates within donors was similar in magnitude to the variation between donors. A study was performed comparing seminal sperm morphometry in single specimens from 30 fertile and 30 infertile men. The sperm head length/width ratio was the parameter that differed the most between these two groups. Moreover, it was the per-ejaculate variability of this parameter, rather than the central tendency, that maximized the difference.

Cytological Techniques↗

The relationship between the motility and morphology of spermatozoa in human semen.

High-speed videomicrography was used to assess simultaneously the morphology and motility of seminal spermatozoa from 10 fertile donors and 10 patients being evaluated for infertility. In both donors and patients, morphologically normal spermatozoa were more likely to be motile and had significantly higher straight line velocity, greater rolling frequency and flagellar beat frequency than abnormally shaped cells. For donors and patients there were highly significant, linear correlations (R = 0.7 to R = 0.98) between the movement characteristics of morphologically normal and abnormal spermatozoa within an ejaculate. A greater percentage of normal donor spermatozoa were motile than were the normal spermatozoa from patients (56% vs. 28%, respectively, P less than 0.005) and normal donor spermatozoa also swam faster than normal patient spermatozoa (49.1 +/- 3.2 microns/sec vs. 37.4 +/- 4.3 microns/sec, mean +/- sem, respectively, P less than 0.05). Overall, a multivariate analysis of variance, including straight line velocity, rolling frequency, beat frequency, and flagellar beat amplitude, demonstrated that these movement characteristics were significantly greater for the normal cells from donors than for the normal spermatozoa from patients. These biologic distinctions notwithstanding, the discrimination between semen from donors and patients was not improved when only morphologically normal cells were analyzed for motility.

Humans↗

Risk factors for occupational illnesses associated with the use of paraquat (1,1'-dimethyl-4,4'-bipyridylium dichloride) in California.

This study was conducted to identify risk factors for paraquat-related occupational illnesses. Pesticide-related illness is a reportable disease in California. A total of 231 skin (26.0%), eye (32.0%), local respiratory (3.5%), and systemic (38.5%) paraquat-related cases were reported to the Worker Health and Safety Branch, California Department of Food and Agriculture, during 1971 through 1985. Following paraquat exposure, we found no cases of pulmonary fibrosis. Annual numbers of cases ranged between 1 and 33 (median = 14 cases/y). Information on illnesses reported during 1981 through 1985 (n = 62) was merged with detailed information on paraquat use in agricultural settings (111,716 applications) for the same years. We found that crop treated, method of application, and season of application all contributed independently to the risk of reported illness. Hand application was associated with a higher risk of illness, compared with air application (RR = 99.1, 95% CI = 22.16-443.47); summer application was associated with a higher risk of illness than was winter application (RR = 4.1, 95% CI = 1.91-8.61); and fruit trees were associated with higher risk of illness than were other crops (mainly cotton) (RR = 3.6, 95% CI = 1.18-11.21).

Adolescent↗