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Featured researches published by Ernest L. Lewis.


The Journal of Urology | 1981

Simultaneous Assessment of Human Sperm Motility and Morphology by Videomicrography

James W. Overstreet; Michael J. Price; William F. Blazak; Ernest L. Lewis; David F. Katz

Videotapes were analyzed to assess sperm motility and morphology in the semen of 5 fertile donors and 20 infertile patients. The slow motion playback control of the video recorder allowed simultaneous assessment of the motility and morphology of individual sperm cells. Similar values were obtained with this method for abnormal morphology more often were immotile or weakly motile than were the normal sperm in the same ejaculates. Normal oval sperm in the semen of infertile men were less likely to be motile and tended to swim more slowly than did morphologically normal sperm in the semen of fertile men.


Fertility and Sterility | 1991

Semen quality in varicocele patients is characterized by tapered sperm cells

Brian N. Naftulin; Steven J. Samuels; Wayne J.G. Hellstrom; Ernest L. Lewis; James W. Overstreet

We used a retrospective case-control study design to compare sperm morphology in 50 varicocele patients and 50 patients with idiopathic infertility. Cases and controls were matched for the percentage of motile sperm and total sperm number per ejaculate. Varicocele patients had significantly more tapered sperm (36% +/- 3% versus 15% +/- 2%) and significantly fewer oval sperm (41% +/- 3% versus 47% +/- 2%). There was no significant difference between cases and controls in any other morphological type.


Fertility and Sterility | 1982

Abnormalities of sperm morphology in cases of persistent infertility after vasectomy reversal

Robert J. Pelfrey; James W. Overstreet; Ernest L. Lewis

Persistent infertility after vasectomy reversal by vasovasostomy may be due to irreversible changes in epididymal physiology, producing morphologic abnormalities of the sperm tail. Specimens from 29 men with persistent infertility following vasectomy reversal were analyzed and sperm motility and morphology were evaluated. the percentage of motile sperm was below normal in 23 specimens. Swimming speed evaluation on 20 specimens showed only 4 were below the normal range. In 19 of the 29 specimens, 10% or more of the sperm cells examined were characterized by a normal head and a coiled or shortened tail. Within this group, the percentage of sperm with tail abnormalities ranged from 2-64%, with a mean of 18.1%. The appearance of sperm tail abnormalities in conjunction with normal or high sperm concentrations suggests a disturbance of epididymal physiology. The epididymal environment is required for the final maturation of spermatazoa and the acquisition of normal motility and fertilizing ability. The study results suggest that these epididymal functions may be impaired in some men after vasectomy. A case report of a 32 year old man who had a vasectomy 7 years prior to referral to the evaluation group, and a successful vasovasostomy 2 years prior, revealed only 20% of the sperm evaluated in the initial specimen had the normal head and tail shape. His semen volume was 3.5 ml with a sperm concentration of 250 million/ml. 25% of the sperm were motile. Reexamination of the semen 8 times during the next year showed no significant changes. The cervical mucus penetration test showed no abnormalities of the sperm-cervical mucus interaction. When the motile sperm were spearated from the immotile cells and incubated with zona-free hamster eggs, all of the eggs were penetrated. Attempts were unsuccessful to isolate sufficient numbers of motile cells for artificial insemination, however, a normal pregnancy was conceived 1 year after the initial evaluation without additional therapy. One other man from the group also produced a pregnancy. It is suggested that the morphologic abnormalities may not confer sterility on the affected individual even when present in the majority of sperm cells, as indicated by the ability of sperm with normal tails to fuse with zona-free hamster eggs in vitro.


The Journal of Urology | 1987

Antisperm Antibodies Bind With Different Patterns to Sperm of Different Men

Wayne J.G. Hellstrom; James W. Overstreet; Sheila M. Moore; Steven J. Samuels; R. Jeffrey Chang; Ernest L. Lewis

Immunologic infertility is an important area of current clinical research. The immunobead test is a laboratory method that identifies the classes of antisperm antibodies and their binding sites on the sperm surface. In this study we have investigated the variability in the pattern of antibody binding to spermatozoa after passive transfer from blood serum. Serum from a single donor containing antisperm antibodies of the IgG class was used in all experiments. The spermatozoa from 27 semen donors were found to differ significantly in the degree and location of immunobead binding after exposure to this serum. There was substantial day-to-day variability in the results for individual semen donors and the overall variability in test results was significantly greater when a number of semen donors was used rather than a single donor. These data suggest that details of antisperm antibody binding after passive transfer from body fluids may depend on the sperm donor. The design of research studies involving antibody transfer must take this source of variability into account.


Fertility and Sterility | 1984

Human sperm function in the ejaculate following vasectomy.

Ernest L. Lewis; Charlene Brazil; James W. Overstreet

Semen specimens were obtained for analysis from nine men immediately before vasectomy and 3 days following the vasectomy procedure. After vasectomy there was a significant decrease in seminal sperm concentration, percentage of sperm motility, and mean swimming speed. In seven of nine cases the spermatozoa did not survive overnight incubation in capacitation media, and in no case was penetration of zonafree hamster oocytes observed 3 days after vasectomy.


Fertility and Sterility | 1985

Measurement of human testicular consistency by tonometry

Ernest L. Lewis; Marianne O'Neill Rasor; James W. Overstreet

A tonometer was used for objective assessment of testicular consistency in a group of 83 men. Testicular measurements in three dimensions were also obtained using calipers. The testicular tonometry value was found to be significantly correlated with the clinical impression of testicular consistency and with testicular size. The testicular tonometry value for the right testicle was significantly larger than the tonometry value for the left testicle in all men except those with azoospermia. The difference in tonometry values between the right and left testicles was most significant in the group of men with left varicocele. The men with varicoceles also had left testicles which were significantly smaller than the paired right testicle in two of three dimensions. In the group with varicocele there was a significant positive correlation between the tonometry value and sperm concentration in the semen. In men with no history of varicocele there was a significant positive correlation between the tonometry value and the percentage of oval sperm.


Urology | 1981

Anterior urethral valves.

Ernest L. Lewis; John M. Palmer

Abstract Anterior urethral valves remain a rare entity despite occasional case reports. Because of its potentially damaging effects on the urinary tract, this condition must be borne in mind when investigating young males with evidence of outflow obstruction or recurring infection. A case is reported, and the modes of diagnosis are emphasized.


The Journal of Urology | 1981

Anuria, A Complication of Anticoagulant Therapy: A Case Report

Richard E. D’anna; Ernest L. Lewis

Abstract We report a case of bilateral ureteral pelvic obstruction causing anuria secondary to anticoagulant therapy. We stress that hematuria encountered in any anticoagulated patient deserves urologic investigation to elucidate the basic pathology involved.


World Journal of Urology | 1986

Immunologic infertility in the male

Ernest L. Lewis; James W. Overstreet

SummaryThere is increased awareness of the role of immunologic factors in the production of male infertility. It is important to recognize and identify the immunoglobulin class and to attempt to demonstrate the mechanisms by which these immunoglobulins exert their effect on the human spermatozoan. There is most likely a spectrum of effects which are seen at various points in the reproductive tract. The use of high and low dose steroids for immunosuppression as well as sperm “washing” provide the best forms of therapy currently available, but a more universally effective form of therapy needs to be developed.


Journal of Andrology | 1986

Morphometric Analysis of Spermatozoa in the Assessment of Human Male Fertility

David F. Katz; James W. Overstreet; Steven J. Samuels; Paul W. Niswander; Todd D. Bloom; Ernest L. Lewis

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Bruno J. Massat

Veterinary Medical Teaching Hospital

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C. Perkins

University of California

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