Hong-Xiang Wang

The sperm protamine mRNA ratio as a clinical parameter to estimate the fertilizing potential of men taking part in an ART programme

STUDY QUESTION Could the protamine-1 to protamine-2 mRNA ratio serve as a biomarker to estimate the fertilizing capacity of sperm from men taking part in an IVF/ICSI programme? SUMMARY ANSWER The protamine mRNA ratio clearly discriminates between fertile and subfertile men and sperm with a normal protamine mRNA ratio exhibit a higher fertilizing capacity in IVF/ICSI. WHAT IS KNOWN ALREADY Aberrant sperm protamine ratios are associated with male factor infertility and mRNA ratio is comparable with protein ratio (due to transcriptional stop in elongating spermatids). STUDY DESIGN, SIZE, DURATION The study population was drawn from subfertile men, whose female partners participated in IVF or ICSI programmes between September 2010 and February 2012. Normozoospermic healthy volunteers served as controls. Sperm cells were lysed, mRNA extracted, reverse transcribed and subjected to real-time quantitative PCR using specific primer pairs for protamine-1 and protamine-2. Relative protamine-1 and protamine-2 mRNA levels were analysed with the Mann-Whitney U-test (two-tailed). PARTICIPANTS/MATERIALS, SETTING, METHODS Quantitative RT-PCR for protamines 1 and 2 has been performed in ejaculates from 32 normozoospermic volunteers (control, University Clinic Giessen, Germany) and 306 patients, whose female partners took part in an IVF (n = 76; University Clinic Hamburg, Germany and Shanghai Jiaotong University, China) or an ICSI (n = 230; University Clinic Munich, Germany and Kinderwunschzentrum Wiesbaden, Germany) programme. MAIN RESULTS AND THE ROLE OF CHANCE The sperm protamine mRNA ratio in normozoospermic men (0.98 ± 0.3) differed significantly from that of ICSI patients (Munich 0.81 ± 0.1; Wiesbaden 0.78 ± 0.2; P < 0.001), while processed samples obtained from IVF patients revealed a normal protamine mRNA ratio (Hamburg 1.0 ± 0.07; Shanghai 1.0 ± 0.54). Normal protamine mRNA ratios were associated with a significantly higher total motile sperm count and a significantly higher percentage of progressively motile sperm. Sperm with a normal protamine mRNA ratio revealed a higher fertilization capacity (fc) in both IVF (53.6% of patients with fc > 80%; P = 0.017) and ICSI (65.1% of patients with fc > 70%; P = 0.028). LIMITATIONS, REASONS FOR CAUTION The protamine mRNA ratio in an individual sperm cell used for ICSI may be different from the overall value obtained from a semen aliquot. WIDER IMPLICATIONS OF THE FINDINGS Data are in line with current literature and suggest the protamine mRNA ratio as a diagnostic marker to estimate the fertilizing capacity of sperm. STUDY FUNDING The German Research Foundation (DFG) to K.S., W.W. and A.P. (STE 892/9-2), as well as to A.S. and H.C.O. (SP721/1-3). COMPETING INTEREST(S) None.

Prediction of sperm retrieval in men with non-obstructive azoospermia using artificial neural networks: leptin is a good assistant diagnostic marker

BACKGROUND At present, non-invasive methods are not comprehensive enough to enable urologists to predict sperm retrieval results accurately in patients with non-obstructive azoospermia (NOA). Our aim was to improve the prediction accuracy of sperm retrieval by using leptin and artificial neural networks (ANNs). METHODS Data from May 2004 to July 2010 for 280 patients with NOA were reviewed and assigned into the training and testing set for ANNs. All patients underwent standard diagnostic infertility evaluation and testicular sperm extraction (TESE). Twelve factors were recorded as the input variables for ANNs: (1)testicular volume, (2)semen volume, seminal pH, seminal alpha-glucosidase and fructose, (3)serum hormones including FSH, LH, total testosterone (TT), prolactin, estradiol, (4)serum and seminal leptin. Three ANN models were constructed with the following input variables: ANN1-(1)(2)(3)(4), ANN2-(1)(2)(3) and ANN3-(1)(2)(4). The prediction accuracy for FSH, leptin and ANN models was compared by receiver operating characteristic (ROC) curve analysis. RESULTS All ANN models were better than FSH. ANN1 had the largest area under the curve (AUC = 0.83) and demonstrated significant improvement compared with FSH (AUC = 0.63, P < 0.01) and leptin (AUC = 0.59, P< 0.01). CONCLUSIONS ANNs improve the prediction accuracy of sperm retrieval. Although the leptin AUC is low, combined use of leptin and FSH can significantly improve the prediction accuracy for sperm recovery in NOA patients. Leptin may be a good assistant marker for diagnosing NOA. However, studies with larger numbers of patients are required to confirm the improved predictive performance of ANNs.

Sperm Protamine mRNA Ratio and DNA Fragmentation Index Represent Reliable Clinical Biomarkers for Men with Varicocele after Microsurgical Varicocele Ligation

PURPOSE We investigated whether the sperm protamine-1/2 mRNA ratio and DNA fragmentation index are reliable biomarkers in patients with clinical varicocele. MATERIALS AND METHODS We performed a prospective study in 42 subfertile patients with left clinical varicocele and 10 normozoospermic healthy donors with proven fertility. All patients and female partners were seen 3 and 6 months after varicocelectomy for fertility examination. Real-time quantitative reverse transcriptase-polymerase chain reaction and SCSA® were performed to analyze the sperm protamine-1/2 mRNA ratio and DNA fragmentation index. RESULTS The protamine-1/2 mRNA ratio and DNA fragmentation index were significantly higher in the preoperative group than in the control group (p <0.01). After varicocelectomy in the pregnant group the protamine-1/2 mRNA ratio recovered to the normal value and the DNA fragmentation index was significantly lower than in the preoperative group (p <0.01). In the nonpregnant group the protamine-1/2 mRNA ratio and DNA fragmentation index did not differ (p >0.05). However, significant differences were present preoperatively according to varicocele severity in the protamine-1/2 mRNA ratio and DNA fragmentation index (p <0.05 and <0.01, respectively) with the highest values in the grade 3 group. Nevertheless, postoperatively no difference in varicocele severity was noted (p >0.05). The protamine-1/2 mRNA ratio was strongly related to preoperative and postoperative sperm concentration (Rs -0.238, p <0.01), progressive motility (Rs -0.327, p <0.01), total motility (Rs -0.206, p <0.05) and DNA fragmentation index (Rs 0.293, p <0.01) except for normal morphology (Rs -0.064, p >0.05). CONCLUSIONS The sperm protamine-1/2 mRNA ratio and DNA fragmentation index can effectively be used to evaluate male fertility. Male infertility due to varicocele may be associated with protamine deficiency and sperm DNA damage. The post-varicocelectomy protamine-1/2 mRNA ratio and DNA fragmentation index are associated with the post-varicocelectomy pregnancy rate.

Capecitabine for the treatment for advanced gastric cancer: efficacy, safety and ethnicity

What is known and Objective:  Capecitabine‐ and 5‐fluorouracil (5‐FU)‐based regimens are widely used for the treatment for advanced gastric cancer (AGC). We aimed to compare the efficacy of the two regimens for both Caucasian and Asian subjects, through a meta‐analysis of the available trial evidence.

Effect of acute tadalafil on sperm motility and acrosome reaction: in vitro and in vivo studies.

Effects of acute tadalafil on sperm motility and acrosome reaction were investigated, both in vitro and in vivo. Twenty asthenozoospermic and 20 normozoospermic patients as control were randomly enrolled. For in vitro part, 0.5 ml tadalafil solutions with different concentrations were added (0.2, 0.1, 0.05 and 0.025 μg ml−1, respectively) into semen samples. In both groups, samples treated with 0.2 μg ml−1 tadalafil had significant increase in sperm motility after 2 h incubation. For in vivo part, oral administration of tadalafil (20 mg) or sildenafil (100 mg) was given. In both groups, computer‐assisted semen analysis parameters showed no significant difference. After the administration of tadalafil (2 h) and sildenafil (1 h), there was no significant difference observed in premature acrosome reaction incidence rate. Taking both in vitro and in vivo results into consideration, acute on‐demand administration of tadalafil would have no adverse effect on semen parameters.

Expression and Role of Leptin under Hypoxic Conditions in Human Testis: Organotypic In Vitro Culture Experiment and Clinical Study on Patients with Varicocele

PURPOSE We investigated the expression and the exact role of leptin under hypoxic conditions in the human testis. MATERIALS AND METHODS Five testes from patients treated with orchiectomy for prostate cancer were used to construct an in vitro hypoxic culture system for human testicular tissue. Immunohistochemistry was performed to analyze leptin protein expression. Leptin, leptin receptor and HIF-1α mRNA were examined by quantitative reverse transcriptase-polymerase chain reaction. Serum and seminal plasma leptin, gonadal hormones and semen parameters were evaluated in 10 healthy donors and 42 infertile patients with varicocele before and after surgery. RESULTS The viability of in vitro cultured testicular tissue was well maintained within 48 hours based on the results of morphological analysis, cell number and cell specific mRNAs. Immunohistochemistry demonstrated that leptin was mainly expressed in seminiferous tubules. Interestingly the optical density of leptin, leptin mRNA and HIF-1α mRNA was significantly increased under hypoxia. Leptin mRNA and HIF-1α mRNA correlated positively (Rs = 0.843, p <0.01). In the clinical study the concentration of seminal plasma leptin before varicocelectomy was markedly higher in patients (mean ± SD 3.01 ± 1.23 ng/l, p <0.01). It was highest in the grade 3 group (mean 3.95 ± 1.37 ng/l, p <0.01) and significantly decreased in the 6-month postoperative group (2.35 ± 0.78, p <0.05). Furthermore, negative correlations were observed between seminal plasma leptin and the sperm concentration (Rs = -0.187, p <0.05), and progressive motility (Rs = -0.234, p <0.05). CONCLUSIONS Leptin expression was induced under hypoxia in the human testis, probably via the HIF-1α related response pathway. Seminal plasma leptin closely correlated with varicocele related spermatogenesis dysfunction. It might effectively reflect the testicular hypoxic environment.

Clinical features and therapeutic strategies of obstructive azoospermia in patients treated by bilateral inguinal hernia repair in childhood

Childhood inguinal herniorrhaphy is one common cause of seminal tract obstruction. Vasovasostomy (VV) can reconstruct seminal deferens and result in appearance of sperm and natural pregnancy in some patients. Secondary epididymal obstruction caused by a relatively long-term vasal obstruction is a common cause of lower patency compared with VV due to vasectomy in adults. From July 2007 to June 2012, a total of 62 patients, with history of childhood inguinal herniorrhaphy and diagnosed as obstructive azoospermia were treated in our center. The overall patency rate and natural pregnancy rate were 56.5% (35/62) and 25.8% (16/62), respectively. 48.4% (30/62) of the patients underwent bilateral VV in the inguinal region, with a patency rate of 76.7% (23/30) and a natural pregnancy rate of 36.7% (11/30), respectively. 30.6% (19/62) of the patients underwent bilateral VV and unilateral or bilateral vasoepididymostomies due to ipsilateral epididymal obstruction with the patency and natural pregnancy rate decreasing to 63.2% (12/19) and 26.3% (5/19). 21.0% (13/62) of the patients merely underwent vasal exploration without reconstruction due to failure to find distal vasal stump, etc. Our study indicate that microsurgical reanastomosis is an effective treatment for some patients with seminal tract obstruction caused by childhood inguinal herniorrhaphy.

Follicle-stimulating hormone as a predictor for sperm retrieval rate in patients with nonobstructive azoospermia: a systematic review and meta-analysis

Noninvasive parameters for predicating sperm retrieval rate (SRR) are desirables. Follicle-stimulating hormone (FSH) has been an important predictor since the first years of testicular sperm extraction. Recent studies showed continuous interests in FSH, with both pros and cons. Thus, we conducted a meta-analysis to evaluate the diagnostic value of FSH as a predictor for patients with nonobstructive azoospermia (NOA) taking testicular sperm retrieval. Eligible diagnosis tests were identified from electronic databases (Cochrane Central Register of Controlled Trials, Medline, and EMBASE) without language restrictions. The database search, quality assessment, and data extraction were performed independently by two reviewers. The reference standard was the sperm retrieval result. Diagnostic value of FSH were explored by area under receiver operation characteristics (ROC) curve using Review Manager, version 5.1.0 (Cochrane Collaboration, Oxford, UK) and Meta-DiSc, version 1.4. Meta regression will be done if there is heterogeneity. Then, we find 11 tests including a total of 1350 patients met the inclusion criteria. Our pooled analysis showed that the area under ROC curve of FSH was 0.72 ± 0.04. Meta regression analyses showed that region and average age have an influence on the diagnostic value. FSH showed more diagnostic value with patients in East Asia and with younger patients. We concluded that FSH had moderate value in independently predicating SRR in men with NOA (area under curve >0.7). More detailed diagnosis tests should be anticipated in the future to confirm the diagnostic value of other noninvasive parameters.

Asexuality development among middle aged and older men.

Objectives To assess erectile function in middle-aged and older men with asexuality status and further analyze their specific reasons for this condition. Subjects and Methods Men who had regular sexual intercourse attempts (sex frequency≥1 time per month) were classified into mild erectile dysfunction (ED), moderate to severe ED and non-ED according to International Index of Erectile Function-5, and men having no sexual intercourse attempts for at least 6 months were defined as having an asexuality status. The risk factors associated with ED were collected in a sample of 1,531 Chinese men aged 40 to 80 years, and the self-report reasons for asexuality were recorded in asexual cohort individually. Comparative analyses and multivariate regression models were conducted among these groups. Results The prevalence rates of ED and asexuality status were 49.9% and 37.2%. The asexuality status group had higher risk factors than the moderate to severe ED group in terms of old age (age≥65, adjusted odds ratio (OR) 17.69 versus (Vs.) 7.19), diabetes (crude OR: 2.40 Vs. 2.36) and hypertension (crude OR: 1.78 Vs. 1.72). The specific reasons for the asexuality status were “erectile difficulty” (52.9%), “do not care about sexuality” (53.5%)”, “no longer necessary to have sexuality at this age” (47.7%), “severe stress” (44.4%), “severe fatigue” (26.3%) and “masturbation” (26.9%). Conclusions Men with an asexual status suffer from higher risk factors for ED than men with moderate to severe ED. The majority of this asexual status could be attributed to a full ED, although the reasons for this transient asexuality also involved sexual attitudes and interests, sexual partners and masturbation.

Microsurgical vasoepididymostomy for patients with infectious obstructive azoospermia: cause, outcome, and associated factors

Azoospermia is of great importance to male infertility. Obstructive azoospermia (OA) due to infection is the most prevalent form of OA in China and has been less studied. We aim to observe the treatment outcome of microsurgical vasoepididymostomy (VE) and also to identify the factors relative to the result after reconstructive surgery. Two hundred and eight men presenting with OA due to infection during the study period from July 2010 to July 2013 were prospectively evaluated. Clinical examination, semen analysis, serum follicle stimulating hormone (FSH), and scrotal ultrasound were done before surgical exploration. Among the 198 men who were selected for surgical procedures, 159 candidates underwent microsurgical VE with sperm detected in the epididymal fluid. As for the other 39 cases, reconstruction was not feasible. The average age was 28.5 ± 3.9 years (range 22-38), with average follow-up being 16.5 ± 5.9 months (range 4-28). According to the 150 cases being followed after VE procedures, the total patency rate was 72% (108/150). During follow-up, 38.7% (58/150) natural pregnancies occurred, with overall live birth rate being 32.7% (49/150). Our data suggested that microsurgical VE is an effective therapy for postinfectious epididymal OA. Individualized counseling with prognosis based on etiology should be offered to patients to select optical therapy.