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Zaazaa A, Adel A, Fahmy I, Elkhiat Y, Awaad AA, Mostafa T. Effect of varicocelectomy and/or mast cells stabilizer on sperm DNA fragmentation in infertile patients with varicocele. Andrology 2017; 6:146-150. [PMID: 29195028 DOI: 10.1111/andr.12445] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/29/2017] [Accepted: 10/24/2017] [Indexed: 02/05/2023]
Abstract
This study aimed to assess the effect of varicocelectomy and/or mast cells (MCs) stabilizer on sperm DNA fragmentation in infertile men with varicocele (Vx). Overall, 120 infertile patients were randomized to three equal treatment arms; patients that underwent varicocelectomy, patients on 1 mg ketotifen twice daily for three months, and patients that underwent varicocelectomy followed with 1 mg ketotifen twice daily for three months. These patients were subjected to history taking, clinical examination, semen analysis, and estimation of sperm DNA fragmentation index (DFI). After 3 months, all investigated groups showed significant improvement regarding the mean total sperm count, sperm concentration, total sperm motility, and sperm normal forms percentage compared with the pre-treatment data. As well, the mean sperm DFI was significantly improved compared with the pre-treatment data; in men that underwent varicocelectomy (34.6% vs. 28.3%), in men on MC stabilizer only (33.4% vs. 27.8%), and in men that underwent varicocelectomy followed by MC stabilizer (34.3% vs. 25.1%). Sperm DFI improvement percentages showed the highest improvement in men that underwent varicocelectomy followed with MC stabilizer compared with the other two groups (26.8% vs. 18.2%, 16.8%). Sperm DFI improvement percentages showed significant increases in the infertile patients with Vx grade III compared to Vx grade II in all investigated groups. It is concluded that in infertile men associated with Vx and high sperm DFI, surgical repair followed with MCs stabilizer significantly improve sperm DFI compared with either surgical repair or MCs stabilizer alone.
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Affiliation(s)
- A Zaazaa
- Department of Andrology, Sexology & STIs, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - A Adel
- Department of Andrology, Sexology & STIs, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - I Fahmy
- Department of Andrology, Sexology & STIs, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Y Elkhiat
- Department of Andrology, Sexology & STIs, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - A A Awaad
- Department of Andrology, Sexology & STIs, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - T Mostafa
- Department of Andrology, Sexology & STIs, Faculty of Medicine, Cairo University, Cairo, Egypt
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Abstract
The 1CH (International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use) Guideline for Detection of Toxicity to Reproduction for Medicinal Products, adopted at the Second ICH Conference in Orlando, FL, U.S.A., emphasized the need for research into the suitability of various methods for the detection of effects on fertility in males. The current project was undertaken to compare the efficiency of methods by evaluating reports in the open literature. The results of the examination of 117 substances or substance classes support the view that histopathology and organ weight analysis provide the best general-purpose means of detecting substances with the potential to affect male fertility. Examinations at up to 4 weeks of treatment appear to be as effective as examinations conducted at later times. Mating with females for detection of effects unrelated to interference with sperm production appears to provide an optimal combination because adding other methodologies does not materially improve the detection rate. As to the timing of the mating trial, a 2-week premating period is as efficient as mating at 4 weeks and apparently more efficient than mating after prolonged premating treatment.
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Affiliation(s)
- Beate Ulbrich
- Federal Institute for Drugs and Medical Devices, Berlin, Germany; Huntingdon Research Centre, Huntingdon, Cambridgeshire, England
| | - Anthony K. Palmer
- Federal Institute for Drugs and Medical Devices, Berlin, Germany; Huntingdon Research Centre, Huntingdon, Cambridgeshire, England
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The Prevalence of Ovarian Varices in Patients with Endometriosis. Ann Vasc Surg 2016; 34:135-43. [DOI: 10.1016/j.avsg.2015.12.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 12/08/2015] [Accepted: 12/10/2015] [Indexed: 11/18/2022]
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Mortimer D, Barratt CLR, Björndahl L, de Jager C, Jequier AM, Muller CH. What should it take to describe a substance or product as 'sperm-safe'. Hum Reprod Update 2013; 19 Suppl 1:i1-45. [PMID: 23552271 DOI: 10.1093/humupd/dmt008] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Male reproductive potential continues to be adversely affected by many environmental, industrial and pharmaceutical toxins. Pre-emptive testing for reproductive toxicological (side-)effects remains limited, or even non-existent. Many products that come into direct contact with spermatozoa lack adequate testing for the absence of adverse effects, and numerous products that are intended for exposure to spermatozoa have only a general assumption of safety based on the absence of evidence of actual harm. Such assumptions can have unfortunate adverse impacts on at-risk individuals (e.g. couples who are trying to conceive), illustrating a clear need for appropriate up-front testing to establish actual 'sperm safety'. METHODS After compiling a list of general areas within the review's scope, relevant literature and other information was obtained from the authors' personal professional libraries and archives, and supplemented as necessary using PubMed and Google searches. Review by co-authors identified and eliminated errors of omission or bias. RESULTS This review provides an overview of the broad range of substances, materials and products that can affect male fertility, especially through sperm fertilizing ability, along with a discussion of practical methods and bioassays for their evaluation. It is concluded that products can only be claimed to be 'sperm-safe' after performing objective, properly designed experimental studies; extrapolation from supposed predicate products or other assumptions cannot be trusted. CONCLUSIONS We call for adopting the precautionary principle, especially when exposure to a product might affect not only a couple's fertility potential but also the health of resulting offspring and perhaps future generations.
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Affiliation(s)
- David Mortimer
- Oozoa Biomedical Inc., Caulfeild Village, West Vancouver, BC, Canada.
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Shiraishi K, Matsuyama H, Takihara H. Pathophysiology of varicocele in male infertility in the era of assisted reproductive technology. Int J Urol 2012; 19:538-50. [PMID: 22417329 DOI: 10.1111/j.1442-2042.2012.02982.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Koji Shiraishi
- Department of Urology, Yamaguchi University School of Medicine, Sanyo-Onoda Municipal Hospital, Yamaguchi, Japan.
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Reichart M, Eltes F, Soffer Y, Zigenreich E, Yogev L, Bartoov B. Sperm ultramorphology as a pathophysiological indicator of spermatogenesis in males suffering from varicocele. Andrologia 2009. [DOI: 10.1111/j.1439-0272.2000.tb02878.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Testicular volume, scrotal temperature, and oxidative stress in fertile men with left varicocele. Fertil Steril 2009; 91:1388-91. [DOI: 10.1016/j.fertnstert.2008.04.044] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2008] [Revised: 04/21/2008] [Accepted: 04/21/2008] [Indexed: 11/24/2022]
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Persistent and recurrent postsurgical varicoceles: venographic anatomy and treatment with N-butyl cyanoacrylate embolization. J Vasc Interv Radiol 2008; 19:539-45. [PMID: 18375298 DOI: 10.1016/j.jvir.2007.11.009] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Revised: 10/30/2007] [Accepted: 11/07/2007] [Indexed: 02/06/2023] Open
Abstract
PURPOSE To elucidate the mechanism of persistence or recurrence of varicoceles after surgical repair by examining the venographic anatomy, and to review the efficacy of treatment of these patients with n-butyl cyanoacrylate (NBCA) embolization. MATERIALS AND METHODS From 2001 to 2007, 17 patients with persistent or recurrent varicoceles were studied by retrograde venography 4 months to 18 years after open surgical repair. All patients were then treated with NBCA glue embolization of the entire gonadal vein and the venographically identified duplications and collateral vessels, with three patients undergoing bilateral procedures. Venographic anatomy and clinical success were retrospectively analyzed. RESULTS The majority of patients (65%) exhibited duplications draining into a single left gonadal vein. Duplications were most frequently found to be confined to the pelvis and inguinal canal. Communication with other retroperitoneal veins, including the renal hilar, lumbar, iliac, and circumaortic renal vein, was relatively uncommon. NBCA embolization effectively treated the main gonadal vein as well as the duplications and communications, with only one patient developing thrombophlebitic complications. CONCLUSIONS Duplication of the gonadal vein in the pelvic or inguinal region with apparent incomplete ligation or resection is a common finding in patients with persistence or recurrence of varicocele after surgery. NBCA embolization effectively treats these duplicated vessels, resulting in a high rate of clinical success on short-term follow-up.
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Zini A, Boman J, Jarvi K, Baazeem A. Varicocelectomy for Infertile Couples with Advanced Paternal Age. Urology 2008; 72:109-13. [DOI: 10.1016/j.urology.2008.02.029] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2008] [Revised: 02/09/2008] [Accepted: 02/16/2008] [Indexed: 11/24/2022]
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Abstract
There are several objectives to be achieved during the diagnostic evaluation of a male partner of an infertile partnership. The first is to identify whether or not there is a male factor present and, if so, whether this is attributable to an underlying medical illness. The second is to identify the cause of reduced male fertility and whether or not it is amenable to therapeutic intervention.
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Affiliation(s)
- Jonathan P Jarow
- Johns Hopkins University, 601 North Caroline Street, Room 4068, Baltimore, MD 21287, USA.
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Pasqualotto FF, Lucon AM, de Góes PM, Sobreiro BP, Hallak J, Pasqualotto EB, Arap S. Semen profile, testicular volume, and hormonal levels in infertile patients with varicoceles compared with fertile men with and without varicoceles. Fertil Steril 2005; 83:74-7. [PMID: 15652890 DOI: 10.1016/j.fertnstert.2004.06.047] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2004] [Revised: 06/09/2004] [Accepted: 06/09/2004] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To assess semen analysis, testicular volume, and hormone levels in fertile and infertile patients with varicoceles and fertile men without varicoceles. DESIGN Retrospective study. SETTING Academic medical center. PATIENT(S) Patients were divided into three groups: fertile men with varicoceles (n = 79), infertile men with varicoceles (n = 71), and fertile men without varicoceles (n = 217). INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Levels of LH, FSH, and total T and testicular volume in fertile and infertile men with varicoceles and fertile controls without varicoceles. RESULT(S) LH (IU/L) and T (ng/dl) levels were not statistically different across the three groups. FSH levels were significantly higher in infertile men with varicoceles (7.8 +/- 7.6 IU/L) than in the fertile men with varicoceles (3.5 +/- 2.1 IU/L) or in fertile men without varicoceles (3.5 +/- 1.9 IU/L). The right testicle was smaller in infertile patients with varicoceles (18.7 +/- 8.3 cm(3)) than in fertile men with varicoceles (25.2 +/- 13 cm(3)) or in fertile men without varicoceles (24.9 +/- 10.7 cm(3)). In addition, the left testicle was smaller in infertile men with varioceles (17.6 +/- 8.9 cm(3)) than in fertile men with varicoceles (21.6 +/- 7.8 cm(3)) or in fertile men without varicoceles (23.4 +/- 8.3 cm(3)). Sperm concentration was lower in infertile men with varicoceles (33.7 +/- 23.3 x 10(6)/mL) than in fertile men with varicoceles (101.8 +/- 76.6 x 10(6)/mL) or in fertile men without varicoceles (111.8 +/- 74.2 x 10(6)/mL). In addition, sperm motility was lower in infertile men with varicoceles (37.2% +/- 23.9%) than in fertile men with varicoceles (53.9% +/- 17.4%) or fertile men without varicoceles (58.9% +/- 15.8%). CONCLUSION(S) Infertile patients with varicoceles have higher levels of FSH, smaller testes, and lower sperm concentration and motility compared with controls with or without varicoceles. No statistical differences were seen in the variables evaluated among the fertile men with incidental varicoceles detected at physical examination and those without varicoceles.
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Affiliation(s)
- Fábio Firmbach Pasqualotto
- Divisão de Clínica Urológica, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
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Abstract
There is a male factor involved in up to half of all infertile couples. Potential etiologies in male factor infertility are many and require thorough evaluation for their accurate identification. A complete medical history in conjunction with a focused examination can allow for an appropriate choice of laboratory and imaging studies. The semen analysis is a crucial first step, but by no means is it sufficient to determine a specific etiology or dictate therapy. A systematic approach is necessary to help guide the work-up and rule out less likely causes. The etiologies discussed within this article are tremendously broad, and the prognosis for any given couple depends, in large part, on the etiology. Without a firm understanding of the genetics, anatomy, physiology, and complex interplay of the male reproductive system, the evaluation becomes an inefficient exercise that often fails to define the precise etiology. Couples with male factor infertility need a systematic approach with the efficiency of ultimate treatment determined largely by the physician's ability to identify the specific cause of the man's reproductive failure.
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Affiliation(s)
- Victor M Brugh
- Department of Urology, Eastern Virginia Medical School, 400 West Brambleton Avenue, Suite 100, Norfolk, VA 23510, USA
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Abstract
There is a male factor involved in up to half of all infertile couples. Potential causes of male factor infertility are many and require thorough evaluation for their accurate elucidation. A complete medical history in conjunction with a focused examination can allow for an appropriate choice of laboratory and imaging studies. The semen analysis is a crucial first step, but it is by no means sufficient to determine cause or dictate therapy. A systematic approach is necessary to help guide the evaluation and exclude less likely causes. The causes discussed within this article are broad, and the prognosis for any given couple depends, in large part, on the cause of the infertility. Without a firm understanding of the genetics, anatomy, physiology, and their interactions necessary to permit full functioning of the male reproductive system, the evaluation becomes an inefficient exercise that often fails to elucidate the precise cause of infertility. Treatment success relies not just on a clinical diagnosis but on a determination of the cause of the male factor infertility. Therefore, couples with a component of male factor infertility need a systematic evaluation directed at the male partner to maximize their reproductive potential.
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Affiliation(s)
- Victor M Brugh
- Division of Male Reproductive Medicine and Surgery, Scott Department of Urology, Baylor College of Medicine, 6560 Fannin, Suite 2100, Houston, TX 77030, USA
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Abstract
Although significant advances have been made in the understanding of varicoceles, a clear pathophysiologic mechanism remains elusive. Most likely, a varicocele is the result of a multifactorial process. Appreciation of the complex venous drainage of the testis remains a key to maximizing the chances for treatment success. Likewise, the advent of microsurgical repair has minimized complications. Fortunately, times have improved since the early nineteenth century, when the French surgeon Delpech (1772-1832) was killed by a disgruntled patient on whom he had performed a varicocele repair.
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Affiliation(s)
- Peter C Fretz
- Department of Urology, University of Iowa, 200 Hawkins Drive, 3 RCP, Iowa City, IA 52242-1089, USA
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Reichart M, Eltes F, Soffer Y, Zigenreich E, Yogev L, Bartoov B. Sperm ultramorphology as a pathophysiological indicator of spermatogenesis in males suffering from varicocele. Andrologia 2000; 32:139-45. [PMID: 10863968 DOI: 10.1046/j.1439-0272.2000.00355.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Varicocele of spermatic veins is considered to be one of the major causes of male infertility associated with reduction of sperm quality. The pathophysiology of this condition is not yet completely understood. The aim of this study was to shed light on the pathophysiology of varicocele by identifying semen parameters, especially sperm ultramorphology, which improve following high ligation of the spermatic vein. Seventy-five males with diagnosed varicocele were included in this study. Semen parameters were assessed prospectively using light microscopy, semen biochemistry and sperm quantitative ultramorphological analysis, before high ligation and 3-9 months after high ligation. The control group consisted of twenty-five untreated varicocele patients who underwent two semen examinations within 3-9 months. No statistical difference in any of the examined variables was found between the two examinations in the control group. The treated patients exhibited a significant improvement in sperm density, progressive motility, percentage of normally formed spermatozoa, agenesis of sperm acrosome, chromatin condensation and incidence of amorphous heads compared with the pretreatment condition (P < or = 0.01). In contradiction, no significant improvement was observed following treatment in any of the sperm tail subcellular organelles. It is concluded that varicocele may cause deleterious alterations in early spermatid head differentiation during spermiogenesis and that varicocele patients with a high incidence of sperm acrosome and nucleus malformations are appropriate candidates for varicocele correction.
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Affiliation(s)
- M Reichart
- Male Fertility Laboratory, Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
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Benoff S, Hurley IR, Barcia M, Mandel FS, Cooper GW, Hershlag A. A potential role for cadmium in the etiology of varicocele-associated infertility. Fertil Steril 1997; 67:336-47. [PMID: 9022613 DOI: 10.1016/s0015-0282(97)81921-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To determine whether mannose ligand receptor and acrosome reaction deficits in sperm from men with varicocele are related to the transition metal content of their semen. DESIGN Cadmium and zinc in semen and blood plasma were assayed for fertile males, men without varicocele who required intracytoplasmic sperm injection to achieve fertilization, and men evaluated for potential varicocele-associated infertility. The relationship between actin cytoskeletal distributions and acrosome status was determined for fertile donor sperm in the presence and absence of exogenous cadmium. SETTING University hospital-based molecular biology research laboratory. PATIENT(S) Patients from two university hospital-based IVF-assisted reproductive technology programs and two male urology private practices. INTERVENTION(S) Fertile donor sperm were exposed to exogenous cadmium during capacitating incubations followed by culture at temperatures up to 41 degrees C. MAIN OUTCOME MEASURE(S) Metal ion levels in semen and blood plasma were determined by graphite furnace atomic absorption spectroscopy. Motile sperm were examined for mannose ligand binding and the ability to undergo spontaneous and induced acrosome reactions. Unfixed, Triton-permeabilized sperm were probed with antiactin and antimyosin antibodies. RESULT(S) Cadmium was elevated and zinc was decreased in the seminal plasma of men with varicocele. The content of these metals in semen and blood was not correlated. Cadmium exposure in vitro reduced mannose receptor expression, acrosome exocytosis, and cytoskeletal formation by fertile donor sperm. CONCLUSION(S) Defects in transition metal regulation or excessive cadmium exposure are involved in varicocele-associated infertility.
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Affiliation(s)
- S Benoff
- North Shore University Hospital, Boas-Marks Biomedical Science Research Center, New York 11030, USA
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Fichorova RN, Dimitrova E, Nakov L, Tzvetkov D, Penkov R, Taskov H. Detection of antibodies toward epididymal sperm antigens--an obligatory step in evaluation of human immunologic infertility? Am J Reprod Immunol 1995; 33:341-9. [PMID: 7576115 DOI: 10.1111/j.1600-0897.1995.tb00902.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
PROBLEM To test the relative impact of epididymal versus ejaculated sperm in immunologic infertility. METHOD Human antibody binding to epididymal and ejaculated spermatozoa was compared by flow cytometry (FCM) since it allows quantitative analysis of viable sperm while ignoring nonsperm cells. To select sera for FCM, GAT, TAT, and ELISA were applied on 145 sera from fertile men, idiopathically infertile and varicocele patients. RESULTS All GAT/TAT-positive infertile patients, a representative group of varicocele patients and the fertile control, were assessed by FCM. Higher reactivity toward epididymal sperm revealed 18/22 sera while only four out of them bound to ejaculated sperm stronger than the control. All varicocele sera were positive against epididymal while negative against ejaculated spermatozoa. CONCLUSIONS Epididymal sperm antigens may play a predominant role in some cases of immunologic infertility. Such patients might not be adequately diagnosed and respectively treated due to the limitations of diagnostic procedures applying only ejaculated spermatozoa.
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Affiliation(s)
- R N Fichorova
- Department of Biology, Medical University, Sofia, Bulgaria
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Abstract
OBJECTIVES To assess the effect of varicoceles on testicular blood flow in man. METHODS Testicular blood flow was measured in 248 consecutive men attending an infertility clinic and 34 fertile volunteers using color duplex ultrasonography. RESULTS The testicular blood flow of men with either clinical and/or subclinical varicoceles was not significantly different from controls without varicoceles. CONCLUSIONS Varicoceles do not significantly alter testicular blood flow in man.
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Affiliation(s)
- J A Ross
- Department of Urology, Bowman Gray School of Medicine, Wake University, Winston-Salem, North Carolina
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Chan SY, Tucker MJ, Leung CK, Leong MK. Association between human in vitro fertilization rate and pregnancy outcome: a possible involvement of spermatozoal quality in subsequent embryonic viability. ASIA-OCEANIA JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1993; 19:357-73. [PMID: 8135668 DOI: 10.1111/j.1447-0756.1993.tb00395.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A conventional view of mammalian fertilization is that the active component of the process: the spermatozoon, by virtue of its progressive motility and acrosomal enzymes, penetrates an otherwise passive oocyte. This concept has placed bias on spermatozoal normality as largely determining the outcome of fertilization; once this has been achieved then the contribution of the spermatozoon is often forgotten, and attention switches to the maternally derived "blue-print" for early embryonic development. Paternal genomic contribution is known to start at the eight-cell stage in the human, but this is usually after the time when early cleavage stage (2 to 8-cell stage) embryos are replaced in human assisted reproductive technologies (ART) procedures such as in vitro fertilization and embryo transfer (IVF-ET). Hence, fundamental abnormal contributions to embryogenesis derived from the fertilizing spermatozoon have often been ignored. Human IVF-ET has permitted far greater powers of analysis of the fertilization event, and fertilization success appears to be determined in such a system by three main factors: spermatozoal quality, oocyte quality, and quality of in vitro culture conditions (the gamete environment). If the second two factors are more carefully controlled than the first, as is the usual emphasis in routine human IVF practice, then any large variation in fertilization rates that are also significantly related to embryonic viability and ultimately pregnancy outcome, may be thought to be more directly associated with original quality of the fertilizing spermatozoon. An analysis of results of 758 IVF cases provides preliminary evidence to show that there is a close association between human in vitro fertilization rate and subsequent embryo viability following replacement. In accepting this hypothesis as a possibility, we should drastically change our attitude from one of the spermatozoon as a robust, simple initiator of embryonic development, and embrace the idea of the vulnerability of such germ cells both during and after their production, and how detrimental influences on this might profoundly affect embryogenesis after successful fertilization.
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Affiliation(s)
- S Y Chan
- Department of Obstetrics and Gynecology, Cedars-Sinai Medical Center, Los Angeles, California
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Affiliation(s)
- S B Jaffe
- Department of Obstetrics and Gynecology, College of Physicians and Surgeons of Columbia University, New York, New York
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