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P J Turek

Publications and source records attributed to P J Turek.

At least 19 recordsLinked to original sources
PubMed2000

Compound genetic factors as a cause of male infertility: case report.

A 40 year old healthy Chinese male with primary infertility was seen in a university male infertility and genetic counselling clinic. He presented with congenital bilateral absence of the vas deferens (CBAVD) and the finding of testis atrophy. Fine needle aspiration mapping of the testis identified and localized sperm production within the testicles for in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Careful evaluation of testicular cytology revealed late maturation arrest of spermatogenesis. Cystic fibrosis gene mutation analysis revealed heterozygosity for the 5T variant within the polypyrimidine tract of intron 8. Cytogenetic analysis revealed a pericentric inversion of chromosome 6 with break points at p12 and q21 [46,XY,inv(6)(p12q21)]. This case illustrates that spermatogenesis is not necessarily normal with congenital bilateral absence of the vas deferens. Compound genetic defects may coexist and underlie male infertility.

Adult↗
PubMed2000

Increased frequency of mutations in DNA from infertile men with meiotic arrest.

In diverse organisms from yeast to mice, mutations in numerous genes required for DNA repair may lead to defects in meiosis. Although it is likely that meiosis is conserved throughout evolution, little is known about the genetics of meiosis in humans even though meiotic arrest associated with azoospermia is common. In this work, we compared the sequence fidelity of a polymorphic marker amplified from DNA of two groups of patients: those with testis biopsy suggesting meiotic arrest and those with normal spermatogenesis who were obstructed. We demonstrated that mutations are more common in DNA from testicular tissue derived from men with meiotic arrest than in DNA from testicular tissue derived from men with normal spermatogenesis and physical obstruction (P < 0.05). No mutations were observed in blood tissue from either group of men. This suggests the possibility that defects in genes required in DNA repair could contribute to meiotic arrest in men just as has been observed in other organisms.

Base Sequence↗
PubMed2000

Relationship between classic histological pattern and sperm findings on fine needle aspiration map in infertile men.

Systematic testis fine needle aspiration (FNA) mapping has been proposed as an adjunctive or alternative diagnostic procedure to biopsy to determine the presence of spermatozoa within infertile testes. This study related testis histology to the global presence or absence of spermatozoa in the same testes determined by FNA cytology. Testis biopsies and FNA mapping were performed in 87 infertile, azoospermic men. A mean of 1.3 biopsies and 14 FNA sites were taken per patient. Biopsies were assessed by recognized histological patterns of normal, Sertoli cell-only, hypospermatogenesis, early and late maturation arrest, sclerosis as well as mixed patterns that included at least two of these histologies. FNA cytological specimens were assessed for sperm presence by an experienced cytologist. Overall, spermatozoa were found by FNA mapping in 52% of patients. A comparison of histology and FNA findings revealed that pure patterns of Sertoli cell-only and early maturation were associated with a very poor likelihood of sperm detection (4-8%). In contrast, patients with other pure pattern histologies or mixed patterns had high rates of FNA sperm detection (77-100%). Similar to reported testicular sperm extraction (TESE) findings, sperm detection with FNA shows wide variation depending on testis histology. Unlike most TESE reports, however, some histological patterns generally reflect a more global testicular dysfunction and poorer likelihood of sperm identification, suggesting the possibility that these phenotypes have a genetic origin. Systematic testis sampling with FNA offers additional geographical information about spermatogenesis that routine biopsies lack and can further guide couple decision-making in severe male factor infertility.

Adult↗
PubMed2000

Diagnostic findings from testis fine needle aspiration mapping in obstructed and nonobstructed azoospermic men.

PURPOSE: Although helpful for defining extratesticular obstruction, the testis biopsy offers limited information on nonobstructive azoospermic testes. Guided by diagnostic biopsies, testis sperm extraction procedures fail in 25% to 50% of patients with nonobstructive azoospermia, largely because it is clinically difficult to know where sperm are located. To provide a more complete assessment of spermatogenesis in nonobstructive azoospermic patients and to simplify the confirmation of sperm production in men with obstruction, we use a systematic, fine needle aspiration "mapping" procedure. We summarize the diagnostic findings in a series of azoospermic men. MATERIALS AND METHODS: From 118 azoospermic infertile men (22 with obstructed and 96 with nonobstructed azoospermia) fine needle aspiration data were used to generate location specific, sperm frequency maps for obstructed and nonobstructive azoospermic testes to determine if "sperm rich" locations existed. RESULTS: Fine needle aspiration map analysis revealed that all aspiration locations from obstructed cases showed sperm. In men with nonobstructive azoospermia, sperm was identified in the right testis in 134 of 652 (20.5%) and in the left testis in 151 of 716 (21.1%) separate aspirations. Rates of sperm detection among various intratesticular sites were not statistically different. In 27.1% of cases the fine needle aspiration map found sperm in men with sperm negative biopsies. The likelihood of heterogeneity in fine needle aspiration sperm findings was 25% within individual nonobstructive azoospermic testes and 19.2% between testis sides. At post-procedure followup of 88 patients (74%), no clinical or surgical complications were observed. CONCLUSIONS: Testis fine needle aspiration mapping is a simple, reliable and informative diagnostic tool in the evaluation of azoospermic infertile men.

Biopsy, Needle↗
PubMed1999

Testis sperm extraction and intracytoplasmic sperm injection guided by prior fine-needle aspiration mapping in patients with nonobstructive azoospermia.

OBJECTIVE: To evaluate intracytoplasmic sperm injection (ICSI) outcomes in a cohort of men with nonobstructive azoospermia who underwent prior fine-needle aspiration (FNA) "maps" to localize sperm and guide testis sperm extraction (TESE). DESIGN: Retrospective clinical study. SETTING: University-based infertility practice. PATIENT(S): A consecutive cohort of 19 infertile, azoospermic men. INTERVENTION(S): Couples underwent IVF-ET in which TESE procedures were informed and directed by prior FNA maps of the testis. MAIN OUTCOME MEASURE(S): Sperm retrieval and pregnancy rates. RESULT(S): In 21 IVF-ET and ICSI cycles, sufficient sperm for all oocytes were retrieved in 20 TESE attempts (95%). A mean of 3.1 biopsies per patient were required, with an average size of 72 mg. Mean operative time for the TESE procedure was 88 minutes. Overall, the two-pronuclear fertilization rate was 66%; ongoing clinical pregnancies were obtained in 10 of 21 initiated cycles (48%). CONCLUSION(S): In an effort to reduce IVF-ET cancellation rates in cases of nonobstructive azoospermia, diagnostic testis FNA can define those patients who are good candidates for TESE. It also directs sperm retrieval and minimizes tissue removal from nonobstructed testes.

Adult↗
PubMed1999

The relative viability of human spermatozoa from the vas deferens, epididymis and testis before and after cryopreservation.

Testicular and epididymal spermatozoa are routinely used with in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) to achieve pregnancies. In addition, excess cryopreserved spermatozoa can be thawed and used for ICSI. However, information on the recovery of epididymal and testicular spermatozoa after freeze-thaw is lacking. This is important to determine the feasibility of using previously cryopreserved aspirated spermatozoa for ICSI. We prospectively compared the viability of fresh and frozen-thawed spermatozoa from the vas deferens, epididymis and testicle by several measures. Testis spermatozoa were obtained from men with non-obstructive azoospermia (n = 5), epididymal spermatozoa from men with obstructive azoospermia (n = 8), and vasal spermatozoa from fertile men by vasal irrigation at vasectomy (n = 5). The viability of fresh spermatozoa was assessed by motility, two vital stains (carboxyfluorescein, 0.08 mg/ml and propidium iodide, 20 mg/ml) and the hypo-osmotic swelling assay (HOS; 100 mmol/l citrate and fructose). After cryopreservation, spermatozoa were thawed and all viability measures repeated. Although fresh vasal spermatozoa were the most motile, testicular spermatozoa exhibited similar, high viability (91 and 86% respectively) by vital stain. Spermatozoa from testis, epididymis and vas deferens survived cryopreservation equally well by vital stain, but not by motility. As a selection measure, the HOS assay identified significantly more viable epididymal and testicular spermatozoa than did motility in both fresh and frozen-thawed populations. It appears feasible to use frozen-thawed extracted spermatozoa for ICSI when motility and a selection measure such as the HOS assay are used. With fresh testis spermatozoa, selection methods may not be necessary prior to ICSI, as cell viability is high.

Cell Survival↗
PubMed1998

Fertility issues and their management in men with testis cancer.

Although a curable malignancy, testis cancer and its treatment have unique associated morbidities that largely affect reproductive dysfunction. In this focused review, the factors that contribute to infertility in men with testis cancer are outlined. The treatment-specific risks to fertility that accompany cancer management are also discussed. Contemporary methods of overcoming infertility in testis cancer patients are addressed, and several exciting and promising experimental approaches to the preservation or restoration of fertility for men with testis cancer are presented.

Humans↗
PubMed1998

Male infertility: analysis of the markers and genes on the human Y chromosome.

The long arm of the human Y chromosome is required for male fertility. Deletions in three different regions can cause severe spermatogenic defects ranging from non-obstructive azoospermia to oligozoospermia. Use of intracytoplasmic sperm injection (ICSI) may allow Y chromosome defects to be passed from father to son. Thus, numerous reports have stressed the need to offer genetic testing to infertile men who select ICSI and a number of reproductive clinics have begun to do so. The primary objectives of this review were: firstly, to discuss the characteristics of the published set of polymerase chain reaction markers and how these characteristics affect interpretation of Y chromosome deletion analysis and secondly, to summarize the recent literature pertaining to the genes on the Y chromosome.

Base Sequence↗
PubMed1998

The mini-micro-epididymal sperm aspiration for sperm retrieval: a study of urological outcomes.

Epididymal sperm aspiration and in-vitro fertilization (IVF) with intracytoplasmic sperm injection is an established treatment for obstructive azoospermia. Sperm aspiration is performed with either an incision or percutaneously. To control costs, minimize morbidity and retain the advantages of both approaches, we developed a mini-incision technique for epididymal aspiration and here report sperm retrieval and procedure-related outcomes. Twenty-six consecutive patients with obstructive azoospermia underwent epididymal sperm retrieval through a 1 cm incision with local anaesthesia to provide spermatozoa for concurrent IVF cycles. The quality of retrieved spermatozoa, the quantity of spermatozoa cryopreserved as well as anaesthetic requirement, recovery time and patient satisfaction were evaluated. Fresh epididymal spermatozoa were retrieved in 25 of 26 (96%) patients. In one patient, testicular sperm extraction was necessary. Excess motile spermatozoa were cryopreserved in 24 of 26 (92%) patients; a mean total motile count of 4.8x10(6) motile spermatozoa were banked. The procedure was performed with 62% of patients receiving minimal i.v. sedation. Post-procedure recovery was rapid, with a median time to return to work of 2.0 days with a median of 2.0 pain pills taken. Procedure-related satisfaction was high. The mini-micro-epididymal sperm aspiration achieves the goals of reliable retrieval of abundant epididymal spermatozoa with a single, minimally morbid procedure. It appears to combine the advantages of the incision and percutaneous approaches.

Adult↗
PubMed1998

Observations on seminal vesicle dynamics in an in vivo rat model.

PURPOSE: To gain understanding of the seminal vesicle as a muscular organ, seminal vesicle compliance and contractile properties were quantified with an in vivo, microsurgical rat model. MATERIALS AND METHODS: Microsurgical dissection was performed on anesthetized rats to enable simultaneous organ filling and monitoring of intraluminal pressures. The reliability and reproducibility of post-ganglionic hypogastric nerve-induced ipsilateral (4 rats) and bilateral (5 rats) seminal vesicle contractile responses were assessed during repeated nerve stimulation. Seminal vesicle resting compliance was assessed during a constant saline infusion (10 rats). Functional performance curves were obtained at fixed fill-volumes by measuring organ contraction after nerve stimulation (4 rats). RESULTS: A reproducible seminal vesicle contractile response was obtained with a nerve stimulation interval > 15 minutes. Bilateral seminal vesicle responses were observed with unilateral nerve stimulation. The resting organ compliance curve with saline filling exhibited a characteristic, triphasic response. Functional performance studies revealed that contractile performance improves as the fill-volume increases until the distensibility limit of the organ is reached. CONCLUSIONS: A reliable, in vivo, rat model of seminal vesicle organ compliance and contractility is described. The seminal vesicle is a highly contractile, compliant smooth muscular organ with dynamic properties analogous to that of the urinary bladder. This experimental system may allow for the investigation of pharmacologic and other physiological influences on in vivo organ activity.

Animals↗
PubMed1997

Hypo-osmotic swelling can accurately assess the viability of nonmotile sperm.

Viable, healthy sperm are preferred for oocyte fertilization with intracytoplasmic sperm injection. Currently, motility is the most widely applied measure of sperm viability. However, with this criterion, viable but immotile sperm are overlooked as candidates for micromanipulation. Supravital stains identify viable sperm but may be toxic to the gamete or embryo. We tested the hypothesis that hypo-osmotic swelling, developed to assess sperm membrane integrity, can accurately determine sperm viability. Thawed sperm from 12 fertile donors were exposed to a hypo-osmotic solution and to two supravital stains. A total of 2,010 sperm were assessed for tail coiling after a 30-min exposure to hypoosmotic solution. By supravital stains, 31% of thawed sperm were viable; 23% showed tail coiling. Among coiled-tail sperm, 100% were viable by supravital stain. As a measure of viability, tail coiling exhibited a sensitivity of 30%, specificity of 100%, and positive predictive value of 100% compared to supravital stains. With a 60-min hypo-osmotic incubation, the specificity (89%) and positive predictive value (78%) decreased significantly (P < 0.05). Therefore, hypo-osmotic swelling accurately detects viable sperm among a nonmotile population. Assay accuracy, however, is very sensitive to the incubation time in hypo-osmotic solution.

Benzimidazoles↗
PubMed1997

Systematic fine-needle aspiration of the testis: correlation to biopsy and results of organ "mapping" for mature sperm in azoospermic men.

OBJECTIVES: This study compares fine-needle aspiration (FNA) and testis biopsy for the ability to detect mature sperm in the testes of azoospermic men. In addition, we introduce the concept of testis "mapping" with FNA and apply it to detect sperm in men with severe testis failure. METHODS: Sixteen patients were evaluated for azoospermia in a university-based infertility clinic. All men had testis biopsies and FNAs from matched testicular sites to assess for the presence of spermatozoa. Adequacy criteria for FNA specimens were strictly defined, and correlative analysis of the two techniques was performed. In addition, a subset of 12 men with nonobstructive azoospermia (NOA) had systematic FNA mapping (more than four FNA sites per testis) to detect mature sperm for potential clinical use. RESULTS: Adequate FNA specimens were obtained in 115 (91.3%) of 126 FNA attempts. Of 34 paired biopsy FNA sites. FNA was seen to be more sensitive than, and equally specific as, testis biopsy for sperm detection. When compared with the biopsy touch imprint, FNA was equally as sensitive and specific. Among men with NOA who underwent FNA mapping, 4 (33%) of 12 had localized "patches" of sperm detected in areas distant from sperm-negative biopsy sites. In 1 case, a pregnancy was achieved with later biopsy and sperm extraction "directed" by previous FNA. CONCLUSIONS: For sperm detection, testis FNA provides equivalent or better information than a testis biopsy. FNA can localize areas of sperm production within the testis and accurately guide sperm extraction procedures in men with NOA.

Biopsy, Needle↗
PubMed1997

Testis biopsies frequently demonstrate sperm in men with azoospermia and significantly elevated follicle-stimulating hormone levels.

PURPOSE: Men with azoospermia, markedly elevated serum follicle-stimulating hormone levels and testicular atrophy were previously considered irreversibly infertile. Thus, testicular biopsy in this patient population was considered unnecessary. However, presently men with even the most severe infertility disorders are potentially able to initiate a pregnancy with intracytoplasmic sperm injection provided sperm can be recovered in even relatively few numbers directly from the testicular tissue. For these reasons we sought to reevaluate the findings from testicular biopsies in these men in the era of advanced micromanipulation techniques. MATERIALS AND METHODS: Chart review identified men with azoospermia, confirmed on a pelleted specimen, and a serum follicle-stimulating hormone level of 3 or more times normal. Mature sperm in the touch preparation cytology and testis biopsy specimen were confirmed. RESULTS: A total of 57 men, most with testicular atrophy, underwent a testicular biopsy and in 17 (30%) mature sperm were identified. The most common diagnosis in these men was severe hypospermatogenesis. Men without sperm most commonly had a pure Sertoli-cell-only pattern. CONCLUSIONS: Men with azoospermia and testicular atrophy with significantly elevated follicle-stimulating hormone levels should undergo testicular biopsy if in vitro fertilization with intracytoplasmic sperm injection is an acceptable approach for the couple.

Adult↗
PubMed1996

Normal human ejaculatory duct anatomy: a study of cadaveric and surgical specimens.

PURPOSE: W examined the anatomy of the ejaculatory ducts in normal men and correlated findings with theories of ejaculatory duct obstruction. MATERIALS AND METHODS: Gross and microscopic anatomical studies were performed on cadaveric and operative specimens derived from radical prostatectomy. RESULTS: Histologically, the ejaculatory ducts are a continuation of the seminal vesicles. However, the thick muscle wall of the seminal vesicle is not present within the ejaculatory duct. Normal ejaculatory duct luminal and wall dimensions are remarkably uniform among men. A luminal diameter of greater than 2.3 mm. defines a dilated system statistically. CONCLUSIONS: The largely collagenous ejaculatory ducts may serve as simple semen conduits instead of muscular tubes with spasmodic, sphincteric or peristaltic properties. The anatomical findings presented suggest several possible mechanisms for the prevention of urinary reflux into the ejaculatory ducts.

Aged↗
PubMed1996

The role of the Sertoli cell in active immunosuppression in the human testis.

OBJECTIVE: To define the involvement of Sertoli cells in immune suppression within the testis by identifying surface receptor molecules that describe or communicate with cells of the immune system. MATERIALS AND METHODS: Ten pairs of human testes obtained from orchidectomy were stained immunohistochemically with established monoclonal antibodies that identify common cells of the immune system. RESULTS: Patterns of staining were similar in all testes. Class I major histocompatibility complex (MHC) antigen, important for self/non-self recognition, was found on Sertoli cells. Class II MHC antigen, important for immune cell interaction and limited to immune cells, was absent. Leu M3, characteristically found on macrophages, was also seen on Sertoli cells but no receptor antigens defining basic T cell types (CD4, CD8), B cells (Leu 12) or natural killer cells (Leu 11) were seen on Sertoli cells. CONCLUSIONS: The Sertoli cell membrane lacks lymphocyte-cell surface markers but harbours somatic cell and macrophage markers. This suggests that immunosuppression within the testis is not maintained through classic lymphocyte receptors. The presence of a macrophage marker is consistent with the known phagocytic activity of the Sertoli cell.

Adult↗