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1.
Arch Androl ; 41(1): 57-65, 1998.
Article in English | MEDLINE | ID: mdl-9642462

ABSTRACT

There is evidence to suggest that reactive oxygen species (ROS) are involved in ischemia-reperfusion injury to the testis. Nitric oxide (NO), a ubiquitous free radical produced by the nitric oxide synthases (NOS), has been implicated in physiologic and pathologic interactions with ROS. We examined the effect of testicular ischemia on germ cell apoptosis and endothelial NOS (eNOS) expression. Adult rats were subjected to unilateral 720 degrees testicular torsion for 1 or 3 hours and 24 hours later, testes were harvested for immunohistochemical studies. Apoptosis was detected by in situ 3' end-labeling of DNA with digoxigenin-ddUTP and eNOS protein was detected using an eNOS monoclonal antibody. Tests subjected to 3 hours of torsion had a threefold increase in apoptotic germ cells per cross-sectional area compared to sham testes (P < .05). In addition to its known expression in Leydig, Sertoli, and vascular endothelial cells, eNOS was detected in the cytoplasm of degenerating germ cells. Consecutive testis sections stained for eNOS and cellular DNA fragmentation demonstrated co-localization of eNOS protein and germ cell apoptosis. The detection of strong immunostaining in apoptotic germ cells supports a role of eNOS in germ cell degeneration after testicular ischemia-reperfusion and suggests that NO is associated with germ cell apoptosis.


Subject(s)
Apoptosis , Nitric Oxide Synthase/metabolism , Reperfusion Injury/pathology , Spermatozoa/pathology , Animals , DNA Fragmentation , Male , Nitric Oxide Synthase Type III , Organ Size , Rats , Rats, Sprague-Dawley , Reperfusion Injury/enzymology , Spermatozoa/enzymology , Staining and Labeling/methods
2.
J Androl ; 19(3): 261-5, 1998.
Article in English | MEDLINE | ID: mdl-9639043

ABSTRACT

The mean mature spermatid count (MMSC) provides a useful, simplified quantitative evaluation of human spermatogenesis that is based on the number of mature spermatids in histological sections of testicular biopsies. Here, the activity of the acid-fast (AF) stain was compared to that of the usual hematoxylin and eosin (H&E) stain in performing the MMSC. Thirty bilateral testicular biopsies showing normal spermatogenesis were chosen retrospectively from 15 subfertile patients with obstructive azoospermia or severe oligospermia. The MMSC was determined on each biopsy by utilizing both H&E and AF stains. The AF stain proved to be specific for the mature spermatids normally counted for the MMSC. It simplified recognition of mature spermatids, thereby shortening the overall time required for the procedure. The mean AF MMSC was lower than the mean H&E MMSC, and the mean interobserver differences were decreased. The AF stain is a superior stain for the MMSC when used in conjunction with the H&E stain for descriptive histology.


Subject(s)
Coloring Agents/standards , Infertility, Male/pathology , Sperm Count , Spermatids , Testis/pathology , Adult , Biopsy , Humans , Hydrogen-Ion Concentration , Male , Middle Aged
3.
Hum Reprod ; 12(8): 1635-41, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9308784

ABSTRACT

Recent investigations have suggested a high prevalence of Y chromosome submicroscopic deletions in men with severely impaired spermatogenesis. We evaluated the frequency of Y chromosome deletions in 160 infertile men using a series of 36 sequence-tagged-sites, emphasizing intervals 5 and 6 of the long arm of the Y chromosome. Peripheral leukocyte DNA was extracted and amplified with two parallel techniques to minimize potential overestimation of the frequency of deletions. The presence of deletions was evaluated relative to patient's sperm concentration, testis volume, and hormonal parameters. Men with sperm concentration <5 x 10(6)/ml had a 7% prevalence of submicroscopic Y chromosome deletions. Deletions were detected in 7% of azoospermic men, 10% of men with <1 x 10(6) spermatozoa/ml, and 8% of men with >1 x 10(6) but <5 x 10(6) spermatozoa/ml. Other clinical parameters did not identify men with Y chromosome deletions prior to polymerase chain reaction (PCR)-based testing for the presence of sequence-tagged-sites. Two distinct regions of Y chromosome deletions were detected, approximately 3.6 Mb and 1.4 Mb in length respectively. These deleted regions are present in AZFb and AZFc respectively. No deletions were detected in AZFa. The loss of these two distinct areas is supported by the finding of highly repetitive sequences along the Y chromosome, predisposing to deletion of specific intervals on the Y chromosome during meiosis. Men with severe male infertility are at high risk for Y chromosome deletions. Testing of men for these genetic abnormalities is indicated prior to treatment with assisted reproduction.


Subject(s)
Gene Deletion , Genetic Testing/methods , Infertility, Male/genetics , Oligospermia/genetics , Spermatogenesis/genetics , Y Chromosome/ultrastructure , Humans , Male , Polymerase Chain Reaction
4.
J Clin Endocrinol Metab ; 82(3): 709-16, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9062469

ABSTRACT

Since the first U.S. report of a successful delivery from in vitro fertilization in 1982 (65), progress in the field of assisted reproduction and micromanipulation has been truly dramatic. Perhaps the most exciting advances have been in the area of male factor infertility. Couples who previously would have been offered donor insemination or adoption are now achieving pregnancies despite severe impairments in semen quality, the presence of only single numbers of sperm in the ejaculate, or unreconstructable reproductive tract obstruction. Techniques of micromanipulation that were revolutionary less than five yr ago are now obsolete, replaced by even more successful methods. Even nonobstructive azoospermia resulting from maturation arrest or other impairments in germ cell development have been added to the list of treatable factors in male infertility, as sperm can frequently be extracted directly from testicular parenchyma that is aspirated or surgically biopsied. For patients without sperm in the testicular parenchyma, round spermatid or secondary spermatocyte injections are at least theoretically possible. Several important questions remain with regard to IVF-ICSI. 1) What should be the specific indications for IVF and IVF-ICSI? Should IVF alone ever be used for male factor infertility? 2) What are the reasons for failure to achieve pregnancy after ICSI, which still represent over half of our attempts at achieving ongoing pregnancies? 3) Can we be certain that using severely impaired or less mature sperm will not result in significant birth defects or in genetic abnormalities that could affect the offspring in adolescence or adulthood? 4) What is the most successful and cost effective approach for the infertile couple with impaired semen parameters? For couples with male factor infertility, careful evaluation and treatment of the man should be considered before assisted reproduction, including ICSI. Contemporary application of ICSI for severe male factor infertility can allow pregnancy rates up to 52% (33), with ongoing pregnancy and live delivery rates as high as 37% per IVF cycle attempt (27). As long as viable sperm are present in the ejaculate or retrievable from the reproductive tract, then ICSI procedures can be applied.


Subject(s)
Fertilization in Vitro , Infertility, Male/therapy , Congenital Abnormalities/etiology , Cytoplasm , Female , Humans , Male , Microinjections , Micromanipulation , Pregnancy , Reproductive Techniques/adverse effects , Spermatozoa
6.
Curr Ther Endocrinol Metab ; 6: 371-80, 1997.
Article in English | MEDLINE | ID: mdl-9174774

ABSTRACT

PIP: Each year in the US, nearly half a million men undergo vasectomy and at least 15 million rely on this form of contraception. This article presents state-of-the-art information on vasectomy and vasectomy reversal. First, it describes the conventional, no-scalpel, percutaneous, and open-ended vasectomy techniques and presents research evidence on short-term complications, time required to achieve azoospermia, and vasectomy failure. The article then reviews findings on the local effects of vasectomy on the testis, rete testis and epididymis, vas deferens, and seminal vesicles and prostate and the development of sperm granulomas. It reports the available evidence on long-term systemic consequences of vasectomy and the risk of genitourinary cancer. Finally, the article considers sterilization reversal, including preoperative evaluation, surgical technique, anesthesia, factors that influence the success of reversal surgery, and the recovery of fertility.^ieng


Subject(s)
Sterilization Reversal , Vasectomy , Adult , Contraception , Genitalia, Male/physiology , Humans , Male , Vasectomy/adverse effects
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