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Biomedical subjects

R Singer

Publications and source records attributed to R Singer.

At least 181 records · Page 10Linked to original sources
PubMedDate not supplied

Motility, vitality and percentages of morphologically abnormal forms of human spermatozoa in relation to sperm counts.

The present work was designed to study the proportions of motile and vital sperms as well as of various types of morphologically defective spermatozoa in both normozoospermic and oligozoospermic human semens, aiming at examining whether with the decrease in sperm counts there is a predilection of certain pathologies of these cells. It was found that, generally, the percentages of non-motile and non-vital spermatozoa and of all abnormal forms examined increase with the degree of oligozoospermia. However, no predilection of particular forms could be observed. It is suggested that morphological abnormalities of spermatozoa could be only a partial expression of pathological processes involved in fertility disorders and that the number of biologically defective spermatozoa may be higher than that assessed by routine laboratory techniques.

Adult↗
PubMedDate not supplied

Separation of normozoospermic human spermatozoa into subpopulations by selective agglutination with peanut agglutinin.

Incubation of human spermatozoa of normozoospermic origin with the galactose specific lectin peanut agglutinin (PNA) resulted in agglutination of the majority of sperm. This finding enabled separation of sperm into two subpopulations. The major one, accounting for 87.0 +/- 12.7 (SD)% consisted of agglutinating sperm (PNA+), while the minor subpopulation (PNA-) did not bind the lectin. The correlation between the percentages of PNA- sperm and acrosome-damaged sperm, as detected by light microscopy prior to separation, was analysed and an overlapping has been found. Light and electron microscopy examination revealed that the PNA- cells were either acrosomeless or possessed severely damaged acrosomes while the PNA+ sperm were mostly free of such pathologies. Following treatment of sperm with fluorescin-conjugated PNA the single cells lacked any labeling while the agglutinates exhibited fluorescence. However, the binding of the lectin to sperm was non-uniform and differences in fluorescence intensity at various parts of the head have been observed. The sialic acid content in PNA+ sperm was found to be significantly higher (7.5 +/- 2.2 micrograms/10(8) sperm) as compared to PNA- sperm (2.1 +/- 0.6 micrograms/10(8) sperm). It was suggested that sialic acid content could be a biochemical indicator of acrosomal integrity. Separation of sperm by selective PNA agglutination might be valuable for elimination of sperm affected by acrosomal pathologies from the ejaculate.

Galactose↗
PubMedDate not supplied

A high proportion of double-headed and double-tailed sperm in semen of a human male. A case report.

We present the case of a patient whose semen contained 30% of sperm with double heads and double tails at various stages of attachment due to abnormal meiosis. The genital system, sperm density, endocrinological profile and karyotype were normal. It is postulated that abundance of the above-noted type of sperm pathology in the human semen might not necessarily be associated with oligozoospermia or fertility impairment.

Adult↗
PubMedDate not supplied

Separation of sub-populations of sperm with higher fertility potential from normal and pathological semen by peanut agglutinin.

Incubation of human sperm from semen with counts below 20 x 10(6)/ml with peanut agglutinin (PNA) resulted in agglutination of about 70% of sperm. An inverse correlation was found between non-agglutinating (PNA) sperm and sperm density (r = 0.48, p less than 0.01) and a direct correlation with acrosome-damaged sperm (r = 0.83, p less than 0.001). Binding of 125I-PNA to sperm revealed high, and possibly also low affinity binding sites on sperm from both normozoospermic and oligozoospermic origins. Quantitative transmission electron microscopy analysis revealed that agglutinated, PNA+, sperm had lower frequency of acrosomeless spermatozoa than PNA(-)-sperm (44% versus 77%) and higher fertility score (+0.18 +/- 0.1 and -1.5 +/- 0.87 respectively, p less than 0.01). Removal of PNA- sperm from oligozoospermic semen may increase the fertility score of the remaining sperm.

Cell Separation↗
PubMedDate not supplied

Inhibition of sialyl transferase activity by gossypol acetic acid in human seminal plasma.

Seventeen aliquots of 15 microliters seminal plasma of human origin were incubated with 25 micrograms, 15 micrograms, 5 micrograms and 2.5 micrograms gossypol acetic acid (GAA), dissolved in BWW containing 0.9% sodium chloride and 0.9% benzyl alcohol, at 37 degrees C for 60 minutes. Following incubation, activity of sialyl transferase (S.T.) was determined by a procedure involving incorporation of radioactive sialic acid into asialofetuin. The activity of S.T., expressed as cpm per hour per 15 microliters seminal plasma was compared to controls consisting in incubation of sperm in BWW containing 0.9% benzyl alcohol and 0.9% sodium chloride. The activity of S.T. in controls represented 61.3 +/- 8.0%-67.7 +/- 8.9% of the activity obtained by incubation with BWW only. GAA was found to exert a dose-dependent inhibition of S.T. activity, ranging from 38.3 +/- 20.6% to 53.4 +/- 19.4% (with 25 micrograms) and from 11.3 +/- 14.8% to 21.9 +/- 14.8% (with 2.5 micrograms).

Gossypol↗
PubMedDate not supplied

Low energy narrow band non-coherent infrared illumination of human semen and isolated sperm.

Sixty-two samples of human normal and abnormal semen and 23 samples of washed sperm were illuminated for 4 minutes with a narrow band non-coherent infrared device (BioBeam). Immediately after illumination the following parameters were examined in comparison with appropriate controls: motility, viability and morphology, fructose content of semen, acrosome reaction of sperm, viscosity of seminal plasma and analysis of the protein pattern. The mean value of motility grade calculated for the total number of 62 semen samples was 2.58 +/- 0.79 versus 2.17 +/- 0.75 (non illuminated controls), P less than 0.005. The mean value of motility grade of 23 samples of washed sperm was 2.89 +/- 0.77 versus 2.43 +/- 0.62, respectively (P less than 0.01). In two illuminated seminal plasma specimens, the viscosity was decreased by 8.8% and 14.8%, the protein content and pattern remained, however, unchanged. Neither the percentages of motile, viable and morphologically normal sperm, nor the fructose content of semen were found to be affected by the illumination.

Acrosome↗
PubMedDate not supplied

Ergonomics: your chair and you.

In a profession such as medical transcription which requires sitting for prolonged periods of time, finding the right chair can be as important to your job performance as using the latest state-of-the-art technology.

Ergonomics↗
PubMedDate not supplied

Some characteristics of azoospermic human semen.

Of 260 volume measurements and 265 fructose determinations on 257 azoospermic semen samples, the volume was normal (1-6 mL) in 78%, low in 16.7%, and high in 5.2%. The percentage of azoospermic samples with low volume was greater than that found for samples containing sperm. Mean fructose concentrations were similar in high-volume and normovolemic azoospermic samples, but significantly lower in low-volume samples. There was no correlation between (a) the etiology of the azoospermia and abnormal semen volume or fructose concentration (save for cases of obstruction and/or atrophic seminal vesicles) or (b) semen volume, fructose concentration, and serum LH, FSH, testosterone, or prolactin.

Adolescent↗
PubMedDate not supplied

Nontraumatic, acute neonatal paraplegia.

Nontraumatic, acute neonatal paraplegia with associated lower limb vascular phenomena is a relatively rare condition. Three such cases are reported. The paralysis is primarily motor with minimal neurologic recovery. Contractures and bizarre deformities develop at an early stage and necessitate repeated orthopaedic intervention. The most likely etiology appears to be a vascular insult to the spinal cord.

Catheterization, Peripheral↗