Absence Of Sperm Research Articles

Effect of D-ribose-L-cysteine on aluminum induced testicular damage in male Sprague-Dawley rats.

ObjectiveThis study investigated the effects of D-ribose and L-cysteine on aluminum-induced testicular damage in male Sprague-Dawley rats.MethodA total number of thirty-five (35) adult male Sprague-Dawley rats were divided into four groups (AD). Group A (comprised five (5) rats) was designated the Control Group that received Physiological Saline; while groups B, C, and D (comprised ten (10) rats) were given 75 mg/kg, 150 mg/kg and 300 mg/kg of body weight of aluminum chloride respectively for 39 days. At day 40, the aluminum-treated groups were subdivided into sub-groups (B1, C1, D1) comprising of five (5) rats each, and 30 mg/kg body weight of Riboceine were administered for twenty (20) days. Groups B, C and D remained on the normal dosage of aluminum chloride for three more weeks (59 days).ResultsAndrological parameters (Sperm count, motility, morphology and testosterone) in the aluminum-treated Groups B and C showed no significant difference in their mean values when compared with their control counterparts, whereas there was a significant reduction in the andrological parameters in Group D rats when compared with the Control animals. Histoarchitecture of the testes "stain with H&E" of Group A, B and C rats appeared normal while Group D rats showed testicular damages with several abnormal seminiferous tubules with incomplete maturation of germinal cell layers and absence of spermatozoa in their lumen; Leydig cells appear hyperplastic. Group B1, C1 and D1 andrological and histological parameters appeared normal.ConclusionRiboceine treatment significantly attenuates aluminum-induced testicular toxicity in male Sprague-Dawley in rats.

Just the Two of Us: Involuntary Childlessness, Causes and Consequences

In the recent decades there has been a growing trend towards controlling fertility yet the desire to have at least one child seems overwhelmingly universal. Involuntarily childless couples undergo trauma and face stigma. Causes of infertility are linked with physiological malfunction. Studies have shown that, social change and its subsequent change in lifestyle along with other social cultural factors are linked to menstruation, conception and carrying the pregnancy full term. The present qualitative study included in-depth interviews with couples experiencing involuntary childlessness, gynaecologists and infertility specialists from Pune city. Majority of the respondents seeking medical assistance belong to the age group of 20–35 years. The causes of infertility can be categorized into genetic, physiological and lifestyle related. The common problems observed in males are lack of sperm motility, count or complete absence of sperm, whereas in females it is obesity and polycystic ovaries syndrome which can be a consequence of erratic and stressful lifestyle. The present research will help trace the socio cultural causes of infertility and the socio cultural pressures of the couples seeking treatment. If along with medical treatment, they are helped to deal with socio cultural circumstances then it may help to mitigate their circumstances.

Single gene defects leading to sperm quantitative anomalies.

Azoospermia, defined by the absence of sperm in the ejaculate, is estimated to affect up to 1% of men in the general population. Assisted reproductive technologies have revolutionized the treatment of infertility, and some azoospermic men, those with a post-meiotic defect, can conceive following the use of viable spermatoza recovered from testicular or epididymal biopsies. Although male infertility is a multifactorial disease, it is believed that genetic factors are predominant in the etiology of azoospermia and severe oligozoospermia. Despite that assumption, substantiated by the high number of infertile knockout (KO) mice and the even higher number of genes expressed essentially in the testis, little is known about the pathophysiology of reduced sperm production, its primary causes or the genetic and epigenetic consequences for the gamete and the future conceptus. The identification of genetic abnormalities is therefore paramount to understand spermatogenesis, to adopt the best course of action for the patient and to provide adequate genetic counseling. We provide here a review of the recent literature on the genetics of azoospermia and oligozoospermia, focusing on defects directly altering sperm production. New sequencing technologies are contributing to the rapid evolution of the recent field of infertility genetics.

To be or not to be [fertile], that is the question.

BackgroundAccording to our literature analysis, there are no data focused on spermatozoa emotional representations in childless men and data on the emotional repercussions of a diagnosis of infertility on men are still scarce. Thus, in this work, we investigated what the presence or absence of spermatozoa in the semen symbolize for men.Material and methodsTo answer this question, 441 childless heterosexual men participated in an anonymous, prospective, Internet-based survey.ResultsIn response to the question “What would having a high or normal sperm count symbolize for you?” the most frequent answer was “ability to father a child”. Men living with a partner were significantly more likely than single men to answer “ability to father a child” (p < 0.05) and less likely to answer “virility” and/or “ability to have an erection/ejaculation” (p = 0.001). In response to the question “If you found out that you had a low sperm count or no spermatozoa at all, how would you feel?”, most of the men stated that they would be disappointed. Men living with a partner were more likely to state that they would feel ashamed (p < 0.05) or guilty with regard to their partner (p < 0.0001).ConclusionsThese preliminary results should help us to improve (i) the way that male infertility is announced (it is easier to find the right words if one understands the possible importance of having a high sperm count) and (ii) the psychological, marital and sexual counselling provided to men with a diagnosis of infertility.

Splicing mutation in Sbf1 causes nonsyndromic male infertility in the rat

In the inbred SHR/OlaIpcv rat colony, we identified males with small testicles and inability to reproduce. By selectively breeding their parents, we revealed the infertility to segregate as an autosomal recessive Mendelian character. No other phenotype was observed in males, and females were completely normal. By linkage using a backcross with Brown Norway strain, we mapped the locus to a 1.2Mbp segment on chromosome 7, harboring 35 genes. Sequencing of candidate genes revealed a G to A substitution in a canonical 'AG' splice site of intron 37 in Sbf1 (SET binding factor 1, alias myotubularin-related protein 5). This leads to either skipping exon 38 or shifting splicing one base downstream, invariantly resulting in frameshift, premature stop codon and truncation of the protein. Western blotting using two anti-Sbf1 antibodies revealed absence of the full-length protein in the mutant testis. Testicles of the mutant males were significantly smaller compared with SHR from 4weeks, peaked at 84% wild-type weight at 6weeks and declined afterward to 28%, reflecting massive germ cell loss. Histological examination revealed lower germ cell number; latest observed germ cell stage were round spermatids, resulting in the absence of sperm in the epididymis (azoospermia). SBF1 is a member of a phosphatase family lacking the catalytical activity. It probably modulates the activity of a phosphoinositol phosphatase MTMR2. Human homozygotes or compound heterozygotes for missense SBF1 mutations exhibit Charcot-Marie-Tooth disease (manifested mainly as progressive neuropathy), while a single mouse knockout reported in the literature identified male infertility as the only phenotype manifestation.

Presencia o ausencia de espermatozoides en el líquido preeyaculatorio

ObjectiveTo determine the presence or absence of sperm in pre ejaculate fluid. Material and methodsA descriptive, cross-sectional study in 25 college male volunteers, aged between 18 and 25 in Barranquilla (Colombia). Each subject was given two slides for making pre-ejaculatory fluid and a container for sampling of seminal fluid; pre-ejaculatory sample was taken first by self-stimulation, and subsequently the sample for semen analysis was collected. Search for sperm in pre-ejaculatory liquid was held in at least 10 fields at ×20 magnification and the two slides. The seminal fluid was processed according to WHO standards. ResultsNone of the pre-ejaculatory fluids examined had sperm. All study subjects had spermiograms with total count in excess of 100 million sperm mobility greater than 50%; the average pH was 8.2±0.5. ConclusionsPre-ejaculatory fluid secreted by the glands of Cowper and Littre during sexual stimulation, does not contain sperm and therefore cannot be responsible for pregnancies occurring in the practice of sexual intercourse where the penis is in contact with the external female genitalia or in practice of withdrawal as a contraceptive method.

MP70-01 IFT140 IS A NOVEL CANDIDATE GENE FOR IMPAIRED SPERMATOGENESIS: IDENTIFICATION BY WHOLE EXOME SEQUENCING AND VALIDATION WITH SANGER SEQUENCING

You have accessJournal of UrologyInfertility: Basic Research & Pathophysiology1 Apr 2016MP70-01 IFT140 IS A NOVEL CANDIDATE GENE FOR IMPAIRED SPERMATOGENESIS: IDENTIFICATION BY WHOLE EXOME SEQUENCING AND VALIDATION WITH SANGER SEQUENCING Amin Herati, Peter Butler, cenk Cengiz, Matthew Bainbridge, James Lupski, Richard Gibbs, Larry Lipshultz, and Dolores Lamb Amin HeratiAmin Herati More articles by this author , Peter ButlerPeter Butler More articles by this author , cenk Cengizcenk Cengiz More articles by this author , Matthew BainbridgeMatthew Bainbridge More articles by this author , James LupskiJames Lupski More articles by this author , Richard GibbsRichard Gibbs More articles by this author , Larry LipshultzLarry Lipshultz More articles by this author , and Dolores LambDolores Lamb More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.1426AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES One third of male factor infertility cases are idiopathic. Many of these cases are likely caused by genetic factors. Non-obstructive azoospermia (NOA) is characterized by the absence of sperm in the ejaculate secondary to the lack of sperm production in the testicle. Advances in genetic and genomic analysis have allowed for the rapid identification of candidate genes in NOA men. The aim of our study was to identify novel variants implicated in the pathogenesis of NOA through whole-exome sequencing (WES). METHODS Homozygosity mapping with whole-exome sequencing was performed using the NimbleGen SeqCap EZ Exome V3 sample preparation kit and the Illumina HiSeq 2000 next-generation sequencing platform to sequence the exomes of two siblings with NOA from a consanguineous family. Genetic mutations that passed filter criteria were then validated using Sanger sequencing. We identified one candidate gene, Intraflagellar Transport Protein 140 (IFT140), based on its expression pattern in testes according to the Human Protein Atlas, as well the mutation′s damage prediction based on two online bioinformatic resources. We subsequently performed Sanger sequencing on 95 NOA men and 26 fertile men, all of whom were treated at our institution. RESULTS WES identified 442 variants in the index patients. Four (0.9%) of these variants passed filter criteria, one of which was a six-nucleotide deletion (HG38, chr16:1,519,961 TCTTGGC>T) in exon 22 of IFT140. Family segregation showed that this mutation was homozygous in the two brothers who underwent WES, as well as in a third brother with NOA and their sister. This mutation was not identified in the 1000 Genome Project and was predicted to be deleterious by the bioinformatics tools, MutationTaster and PROVEAN. Sanger sequencing validated the mutation in this family and identified it as a heterozygous mutation in 1 (1.1%) of the 95 NOA men and none of the 26 fertile controls in our cohort. Pathologic correlation of this unrelated patient showed hypospermatogenesis with a clinical history significant for three failed cycles of in vitro fertilization (IVF). CONCLUSIONS We have identified through WES a small indel mutation in IFT-140 as a novel, disease-causing variant. This mutation was detected in our cohort of NOA in addition to the index family assessed with a prevalence of 1.1%. Further studies are required to determine the role of IFT140 in spermatogenesis. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e905-e906 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Amin Herati More articles by this author Peter Butler More articles by this author cenk Cengiz More articles by this author Matthew Bainbridge More articles by this author James Lupski More articles by this author Richard Gibbs More articles by this author Larry Lipshultz More articles by this author Dolores Lamb More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

An easy, reproducible and cost-effective method for andrologists to improve the laboratory diagnosis of nonobstructive azoospermia: a novel microcentrifugation technique.

ABSTRACTThis study describes a new method of microcentrifugation as an improved, viable, cost-effective option to the classical Cytospin apparatus to confirm azoospermia. Azoospermic semen samples were evaluated for cryptozoospermia by a centrifugation method similar to that of World Health Organization guidelines (2010; entire specimen centrifuged at 3000g for 15 min, and aliquots of the pellet examined). Then, if no sperm were detected, the pellet from that procedure was resuspended in culture medium, centrifuged (2000g for 15 min), and the entire pellet spread on a 4 X 6mm area of a slide and stained using the Christmas tree method (Nuclear-Fast solution and picric acid). The entire stained area was examined for the presence or absence of sperm. A total of 148 azoospermic samples (after standard WHO diagnosis) were included in the study and 21 samples (14.2%) were identified as sperm-positive. In all microcentrifugation slides, intact spermatozoa could be easily visualized against a clear background, with no cellular debris. This novel microcentrifugation technique is clearly a simple and effective method, with lower cost, increasing both sensitivity and specificity in confirming the absence or presence of spermatozoa in the ejaculate. It may represent a step forward of prognostic value to be introduced by andrology laboratories in the routine evaluation of patients with azoospermia in the initial semen analysis.

Pre-operative risk factors associated with need for vasoepididymostomy at the time of vasectomy reversal.

The absence of sperm in the ejaculate after vasectomy reversal is commonly caused by failure to recognize and subsequently bypass epididymal or proximal vasal obstruction at the time of vasectomy reversal. If intra-operative proximal obstruction is suspected, vasoepididymostomy (VE) is recommended rather than vasovasostomy (VV). We sought to calculate the associated risk of needing VE, rather than VV with time from original vasectomy (obstructive interval) using a large cohort of vasectomy reversal patients. We reviewed the electronic and paper vasectomy reversal database by a single surgeon from 1978 through 2012. We performed univariate analysis to identify variables that predicted the need for VE rather than VV, and then combined only significant univariates into our multi-variable analysis. 2697 total men underwent vasectomy reversal, and 239 were repeat procedures. Of the 5296 individual testes operated on, 1029 were VE. Significant variables that predicted the need for VE on univariate analysis included: age, obstructive time interval, vasectomy reversal after previous VV (repeat vasectomy reversal), and year the procedure was performed. On multi-variable analysis significant risk factors for VE were age above 50 (OR 1.36), repeat vasectomy reversal (OR 5.78), and greater obstructive time interval (OR 1.56). For every 3years since original vasectomy, the risk of needing VE increases by 56%. There is a linear relationship between obstructive interval and need for VE. Men undergoing repeat vasectomy reversal have five times greater risk of requiring VE and men greater than 50years of age are also at higher risk. Using these pre-operative predictors is helpful in identifying patients who will benefit from referral to an experienced surgeon who can perform VE.

Novel methods for the molecular discrimination of Fasciola spp. on the basis of nuclear protein-coding genes

Fasciolosis is an economically important disease of livestock caused by Fasciola hepatica, Fasciola gigantica, and aspermic Fasciola flukes. The aspermic Fasciola flukes have been discriminated morphologically from the two other species by the absence of sperm in their seminal vesicles. To date, the molecular discrimination of F. hepatica and F. gigantica has relied on the nucleotide sequences of the internal transcribed spacer 1 (ITS1) region. However, ITS1 genotypes of aspermic Fasciola flukes cannot be clearly differentiated from those of F. hepatica and F. gigantica. Therefore, more precise and robust methods are required to discriminate Fasciola spp. In this study, we developed PCR restriction fragment length polymorphism and multiplex PCR methods to discriminate F. hepatica, F. gigantica, and aspermic Fasciola flukes on the basis of the nuclear protein-coding genes, phosphoenolpyruvate carboxykinase and DNA polymerase delta, which are single locus genes in most eukaryotes. All aspermic Fasciola flukes used in this study had mixed fragment pattern of F. hepatica and F. gigantica for both of these genes, suggesting that the flukes are descended through hybridization between the two species. These molecular methods will facilitate the identification of F. hepatica, F. gigantica, and aspermic Fasciola flukes, and will also prove useful in etiological studies of fasciolosis.

Stains of ejaculated pre and post-vasectomy: Purity and sufficient quantity of recovered DNA after 10 years of storage

Vasectomy is a widely used method of contraception. The absence of spermatozoa in the ejaculate of azoospermic individuals increases the difficulty of extracting DNA for analysis, especially if the biological samples are in the form of spots and stored for years. The aim of this study is to evaluate the possibility of obtaining autosomal and Y-STR profiles from stains containing the ejaculate of individuals pre and post-vasectomy, stored in cotton fabric for a period of 10 years. Samples from 28 (twenty eight) individuals: semen pre-vasectomy and seminal fluid (post-vasectomy) stains, stored from 2004 to 2014 at room temperature were used. Three cutouts of 1.5cm in diameter (punch) were taken from central region of each spot. It was used the QIAamp DNA Mini kit (Qiagen) to extract DNA with an adapted protocol followed by quantification by Nanodrop equipment. Genetic profiles were obtained using ESI17PowerPlexR (Promega). Capillary electrophoresis was performed on the ABI PRISM 3500XL DNA Analyzer. The DNA extraction was successful in all punch analyzed, and its concentration ranged from 1.1ng/uL to 23.3ng/uL in the pre- vasectomy and from 0.8ng/uL to 7ng/uL in postvasectomy punch. The samples had suitable purity, reflecting the presence of few contaminants. Currently, the techniques of DNA amplification are extremely sensitive and capable of assessing human DNA in small quantities generating partial or full profiles, trespassing situations such as long storage periods in cotton fabric. These data can be used as a benchmark for forensic analysis in cases of semen analysis.

Evidence for mate-encounter Allee effect in an invasive longhorn beetle (Coleoptera: Cerambycidae)

1. Limited empirical support is available for mate-encounter Allee effects in invasive insects due to the logistical challenges of studying demographic trends in low-density populations. 2. Traps baited with pheromone and spruce volatiles were used to monitor the abundance of female Tetropium fuscum F. (Coleoptera: Cerambycidae) at multiple sites in Nova Scotia in 2011 and 2012. Each female was dissected to determine the presence or absence of sperm in its spermatheca (mated or virgin female, respectively). 3. Both male and total T. fuscum abundance declined with increasing distance to the focal point of T. fuscum's invasion. Female mating probability declined with male abundance and with distance from the invasion focus, and mating probabilities were very low at the most peripheral sites. Difficulty in encountering mates may thus contribute to limiting the spread of T. fuscum. 4. The approach outlined here could be integrated into existing surveys of wood borers using traps baited with semiochemicals to improve our understanding of the role of the mate-encounter Allee effect in invasion dynamics.

AB068. Practical diagnosis and treatment algorithm for azoospermia

A male factor is solely responsible in approximately 20% of cases of infertility and contributory in another 30-40%. Azoospermia is present in 15-20% of infertile males. Although the main goal of the evaluation of the infertile men is to identify the reversible conditions, to identify the irreversible causes that can or cannot be managed by assisted reproductive techniques (ART) is also important. Etiologies for azoospermia can be categorized as pre-testicular, testicular and post-testicular. Azoospermia is defined as the absence of sperm from at least two centrifuged semen samples. The initial evaluation of the azoospermia men includes a thorough history, physical examination, and hormonal tests. Physical examination should focus on testis size and presence of vas deferens and varicocele. Hormonal evaluation should include measurement of serum testosterone and follicle stimulating hormone (FSH) levels. When the vasa are palpable, testis size, semen volume and serum FSH are key factors in determining the etiology of the azoospermia. If the semen volume is reduced and this is not an artifact, the first laboratory test is post-ejaculatory urinalysis to exclude a retrograde ejaculation. After exclusion of retrograde ejaculation, transrectal ultrasonography (TRUS) should be considered to identify ejaculatory duct obstruction (EDO). Dilation of the seminal vesicles serves as a sign of EDO. Seminal vesicle aspiration to identify sperm at the time of TRUS can increase the diagnostic accuracy. In our center, TRUS-guided opacification of the seminal tracts with a mixture of contrast media and dye is performed to facilitate effective transurethral resection (TUR) of ejaculatory duct. Based on our experiences, patients with midline cysts who are treated by TUR are expected to have the best outcome. Testis size and level of serum FSH in azoospermic males with normal semen volume are critical factors in determining diagnostic strategies. Men with elevated FSH and bilateral small testis have non-obstructive azoospermia (NOA). Diagnostic testicular biopsy is not required in cases of NOA. Elevated FSH is indicative of a significant problem with spermatogenesis whereas a normal serum FSH does not guarantee intact spermatogenesis. Therefore, patients with normal testis size and FSH level should undergo a testicular biopsy to provide a definitive diagnosis. If the testicular biopsy is normal, most men have bilateral epididymal obstruction. Epididymal obstruction can be identified only by surgical exploration. Vasography is performed at the time of reconstructive surgery. Once sperm are found from the epididymal tubule, vasoepididymostomy is performed. The best results can be achieved by surgeons with training and on-going experience in microsurgery. There is some evidence that a small percentage of men with NOA may benefit from treatment of a clinical varicocele. Therefore, it is reasonable to offer men with NOA and clinical varicoceles a varicocelectomy. However, the most men will still need to use intracytoplasmic sperm injection (ICSI) to conceive. Testicular sperm extraction (TESE) should be offered to all men with NOA. Microsurgical TESE increases retrieval rates, and should be preferred in severe cases of NOA.

The Stability of Prostate-Specific Antigen in Semen Under Various Temperatures.

Prostate-specific antigen (PSA) is most commonly used for identifying semen, especially in the absence of sperm. However, PSA concentration varies according to storage temperature and duration, and little is known about its stability in semen. This study was therefore aimed to determine the stability under five different temperatures: -80, -20, 4, 25, and 37°C; and nine different durations: 1, 2, 3, 5, 7, 14, 30, 90, and 180days. All samples were stored at -80°C after being secreted from the volunteers' body until analyzed. Results showed that the PSA concentration declined significantly over time under all temperatures studied except -80°C. At -20 and 4°C, PSA was still detectable on Day 180 with 50% and 70% decrease from its original concentration, respectively. At 25 and 37°C, PSA was detected up to Day 7 and 3, respectively. This information might assist forensic scientists understand more about PSA nature and integrate it into their works.

Giant-sized chromosomes in genus Phyllobrotica Chevrolat 1837 (Coleoptera: Chrysomelidae: Galerucinae) and parthenogenesis in P. adusta (Creutzer 1799)

SummaryOnly females were detected in a small population of Phyllobrotica adusta (Creutzer 1799) (Chrysomelidae: Galerucinae) located in a mountain near Kastoria (Greece). Their karyotype, composed of 42 chromosomes, including three giant-sized ones, is assumed to be triploid. Only two giant-sized chromosomes were present in the 37,X/38,XX karyotype of the congeneric sexual species P. quadrimaculata (L. 1758). Although males were described in P. adusta, the abnormal sex ratio, the presumed triploidy and the absence of spermatozoa in the spermatheca strongly suggest a parthenogenetic reproduction of the population studied. Both parthenogenesis and giant-sized chromosomes have been described independently in some species of Neotropical and Palearctic Galerucinae, but never together.

SEPT12/SPAG4/LAMINB1 Complexes are Required for Maintaining the Integrity of the Nuclear Envelope in Postmeiotic Male Germ Cells

Male infertility affects approximately 50% of all infertile couples. The male-related causes of intracytoplasmic sperm injection failure include the absence of sperm, immotile or immature sperm, and sperm with structural defects such as those caused by premature chromosomal condensation and DNA damage. Our previous studies based on a knockout mice model indicated that SEPT12 proteins are critical for the terminal morphological formation of sperm.

Metodologia da análise seminal para pacientes azoospérmicos no Laboratório Fleury

The azoospermia is defined as the absence of sperm in the ejaculate by the seminal fluid man after centrifugation technique conducted in at least two samples. Given the importance of a correct diagnosis of the seminal analysis for couples, all sample no sperm present in fresh examination should follow in laboratory tests. Thus the present study aims to analyze the results of a spin rate of ejaculate or all of the ejaculate volume of patients with azoospermia to determine the best method to be used in semen analysis for this group of patients.

An association study of four candidate loci for human male fertility traits with male infertility.

Are the four candidate loci (rs7867029, rs7174015, rs12870438 and rs724078) for human male fertility traits, identified in a genome-wide association study (GWAS) of a Hutterite population in the USA, associated with male infertility in a Japanese population? rs7867029, rs7174015 and rs12870438 are significantly associated with the risk of male infertility in a Japanese population. Recently, a GWAS of a Hutterite population in the USA revealed that 41 single-nucleotide polymorphisms (SNPs) were significantly correlated with family size or birth rate. Of these, four SNPs (rs7867029, rs7174015, rs12870438 and rs724078) were found to be associated with semen parameters in ethnically diverse men from Chicago. This is a case-control association study in a total of 917 Japanese subjects, including 791 fertile men, 76 patients with azoospermia and 50 patients with oligozoospermia. Azoospermia was diagnosed on the basis of semen analysis (the absence of sperm in ejaculate), serum hormone levels and physical examinations. Oligozoospermia was defined as a sperm concentration of <20 × 10(6)/ml. We excluded patients with any known cause of infertility (i.e. obstructive azoospermia, varicocele, cryptorchidism, hypogonadotropic hypogonadism, karyotype abnormalities or complete deletion of AZF a, b or c). The SNPs rs7867029, rs7174015, rs12870438 and rs724078 were genotyped using DNA from peripheral blood samples and either restriction fragment length polymorphism PCR or TaqMan probes. Genetic associations between the four SNPs and male infertility were assessed using a logistic regression analysis under three different comparative models (additive, recessive or dominant). The genotypes of all four SNPs were in Hardy-Weinberg equilibrium in the fertile controls. The SNPs rs7867029 and rs7174015 are associated with oligozoospermia [rs7867029: odds ratio (OR) = 1.70, 95% confidence interval (CI) = 1.07-2.68, P = 0.024 (log-additive); rs7174015: OR = 6.52, 95% CI = 1.57-27.10, P = 0.0099 (dominant)] and rs12870438 is associated with azoospermia (OR = 10.90, 95% CI = 2.67-44.60, P = 0.00087 (recessive)] and oligozoospermia [OR = 8.54, 95% CI = 1.52-47.90, P = 0.015 (recessive)]. The association between rs7174015 and oligozoospermia under a dominant model and between rs12870438 and azoospermia under additive and recessive models remained after correction for multiple testing. There were no associations between rs724078 and azoospermia or oligozoospermia. Even though the sample size of case subjects was not very large, we found that three SNPs were associated with the risk of male infertility in a Japanese population. The three infertility-associated SNPs may be contributing to a quantitative reduction in spermatogenesis. This study was supported in part by the Ministry of Health and Welfare of Japan (1013201) (to T.I.), Grant-in-Aids for Scientific Research (C) (23510242) (to A.Ta.) from the Japan Society for the Promotion of Science, the European Union (BMH4-CT96-0314) (to T. I.) and the Takeda Science Foundation (to A.Ta.). None of the authors has any competing interests to declare.

Morphometric study of the testis and reproductive tract (including sperm granuloma) after vasectomy in mature rats

By utilizing the rabbit model, previous studies have found good evidence indicating that vasectomy-induced spermatogenic damage is pressure-mediated: the damage occurs when the occluded reproductive tract is unable to accommodate additional spermatozoa produced by the testis. More studies with the more commonly used rat model have shown, however, controversial results on whether and why the damage occurs. In this study, 12 mature male Sprague-Dawley rats were subjected to unilateral vasectomy: double ligation (without severing) of the vas deferens exposed via a small inguinal incision; 37 days after the operation, the testes, epididymides, vasa deferentia (juxta-epididymal segments), and sperm granulomas (at the vasectomy site) were removed to obtain methacrylate resin-embedded sections and morphometric studies carried out with light microscopy. Marked spermatogenic damage with spermatids and spermatocytes depleted in the seminiferous epithelium in 43% of the seminiferous tubule profiles was demonstrated in 5 of the 12 testes on the vasectomized side, and the damage was associated with smaller or absent sperm granulomas; in the other 7 testes with essentially normal spermatogenesis, there was an increase (by 111% on average) in the volume of the tubule lumen, associated with larger granulomas or granulomas containing more spermatozoa. There was an overall increase (by 66%) in the thickness of the rete testis in the 12 testes; the epididymis or vas deferens showed no distension. It seems therefore that the spermatogenic damage induced by vasectomy in rats is pressure-mediated as well, and that variation in the damage depends mainly on the postoperative development of the sperm granuloma.

Detection of insemination status in live Aedes aegypti females

Using the technique described in this report, the presence or absence of sperm in spermathecae of female Aedes aegypti is detectable without dissection. Spermathecae of a lightly anesthetized female can be visualized by phase contrast microscopy through the distended abdomen, after the intersegmental membranes are stretched by ventral placement of a glass cover slip. Most females recovered after the procedure were capable of subsequent reproductive activities. Albeit tedious, this technique preserves the female alive for subsequent experiments or observations. Its extension to other mosquito species, or other Diptera and insects, will depend on spermathecal and sperm visibility through the distended abdomen.