Bi-allelic MEI1 variants cause meiosis arrest and non-obstructive azoospermia.

Non-obstructive azoospermia (NOA) is characterized by the failure of sperm production due to testicular disorders and represents the most severe form of male infertility. Growing evidences have indicated that gene defects could be the potential cause of NOA via genome-wide sequencing approaches. Here, bi-allelic deleterious variants in meiosis inhibitor protein 1 (MEI1) were identified by whole-exome sequencing in four Chinese patients with NOA. Testicular pathologic analysis and immunohistochemical staining revealed that spermatogenesis is arrested at spermatocyte stage, with defective programmed DNA double-strand breaks (DSBs) homoeostasis and meiotic chromosome synapsis in patients carrying the variants. In addition, our results showed that one missense variant (c.G186C) reduced the expression of MEI1 and one frameshift variant (c.251delT) led to truncated proteins of MEI1 in in vitro. Furthermore, the missense variant (c.T1585A) was assumed to affect the interaction between MEI1 and its partners via bioinformatic analysis. Collectively, our findings provide direct genetic and functional evidences that bi-allelic variants in MEI1 could cause defective DSBs homoeostasis and meiotic chromosome synapsis, which subsequently lead to meiosis arrest and male infertility. Thus, our study deepens our knowledge of the role of MEI1 in male fertility and provides a novel insight to understand the genetic aetiology of NOA.

Identification of a missense variant of MND1 in meiotic arrest and non-obstructive azoospermia.

Meiotic arrest is a common pathologic phenotype of non-obstructive azoospermia (NOA), yet its genetic causes require further investigation. Meiotic nuclear divisions 1 (MND1) has been proved to be indispensable for meiotic recombination in many species. To date, only one variant of MND1 has been reported associated with primary ovarian insufficiency (POI), yet there has been no report of variants in MND1 associated with NOA. Herein, we identified a rare homozygous missense variant (NM_032117:c.G507C:p.W169C) of MND1 in two NOA-affected patients from one Chinese family. Histological analysis and immunohistochemistry demonstrated meiotic arrest at zygotene-like stage in prophase I and lack of spermatozoa in the proband's seminiferous tubules. In silico modeling demonstrated that this variant might cause possible conformational change in the leucine zippers 3 with capping helices (LZ3wCH) domain of MND1-HOP2 complex. Altogether, our study demonstrated that the MND1 variant (c.G507C) is likely responsible for human meiotic arrest and NOA. And our study provides new insights into the genetic etiology of NOA and mechanisms of homologous recombination repair in male meiosis.

A homozygous frameshift variant in SYCP2 caused meiotic arrest and non-obstructive azoospermia.

Genetic causation for the majority of non-obstructive azoospermia (NOA) remains unclear. Mutations in synaptonemal complex (SC)-associated genes could cause meiotic arrest and NOA. Previous studies showed that heterozygous truncating variants in SYCP2 encoding a protein essential for SC formation, are associated with non-obstructive azoospermia and severe oligozoospermia. Herein, we showed a homozygous loss-of-function variant in SYCP2 (c.2689_2690insT) in an NOA-affected patient. And this variant was inherited from heterozygous parental carriers by natural reproduction. HE, IF, and meiotic chromosomal spread analyses demonstrated that spermatogenesis was arrested at the zygotene stage in the proband with NOA. Thus, this study revealed that SYCP2 associated with NOA segregates in an autosomal recessive inheritance pattern, rather than an autosomal dominant pattern. Furthermore, our study expanded the knowledge of variants in SYCP2 and provided new insight into understanding the genetic etiology of NOA.

Bi-allelic SPATA22 variants cause premature ovarian insufficiency and nonobstructive azoospermia due to meiotic arrest.

The genetic causes of idiopathic premature ovarian insufficiency (POI) and nonobstructive azoospermia (NOA) remain unclear. We performed whole-exome sequencing (WES) in members of a consanguineous family with two POI and two NOA patients to screen for potential pathogenic variants for familial POI and NOA. And a homozygous variant in SPATA22 (c.400C>T:p.R134X) was identified. Histological analysis and spermatocyte spreading assay demonstrated that the spermatogenesis was arrested at a zygotene-like stage in the proband with NOA. The candidate gene was further screened in the in-house WES database of idiopathic POI-affected patients. One additional compound heterozygous variant in SPATA22 (c.900+1G>A and c.31C>T:p.R11X) was found in one patient with sporadic POI and validated by minigene assay. Thus, this is the first report identifying SPATA22 as the causative gene for human POI. Combined with the observations in the familial patient with NOA, our findings highlighted the essential role of meiotic HR genes in gametogenesis and gonadal function maintenance.

Predictive Value of Corrected 18 F-FDG PET/CT Baseline Parameters for Primary DLBCL Prognosis: A Single-center Study.

Objective The purpose of this study was to evaluate the prognostic significance of corrected baseline metabolic parameters in fluorodeoxyglucose positron emission tomography imaging ( 18 F-FDG PET/CT) for 3-year progression-free survival (PFS) in patients with primary diffuse large B cell lymphoma (DLBCL). Patients and Methods Retrospective clinical and pathological data were collected for 199 patients of DLBCL diagnosed between January 2018 and January 2021. All patients underwent 18 F-FDG PET/CT scans without any form of treatment. The corrected maximum standardized uptake value (corSUVmax), corrected mean standardized uptake value (corSUVmean), corrected whole-body tumor metabolic volume sum (corMTVsum), and corrected total lesion glycolysis of whole body (corTLGtotal) were corrected using the SUVmean in a 1-cm diameter mediastinal blood pool (MBP) from the descending thoracic aorta of patients. Kaplan-Meier survival curves and Cox regression were used to examine the predictive significance of corrected baseline metabolic parameters on 3-year PFS of patients. The incremental values of corrected baseline metabolic parameters were evaluated by using Harrell's C-indices, receiver operating characteristic, and Decision Curve Analysis. Results The multivariate analysis revealed that only the National Comprehensive Cancer Network (NCCN)-International Prognostic Index (IPI) and corMTVsum had an effect on 3-year PFS of patients ( p < 0.05, respectively). The Kaplan-Meier survival analysis demonstrated significant differences in PFS between the risk groups classified by corSUVsum, corMTVsum, and corTLGtotal (log-rank test, p < 0.05). The predictive model composed of corMTVsum and corTLGtotal surpasses the predictive performance of the model incorporating MTVsum and TLGtotal. The optimal performance was observed when corMTVsum was combined with NCCN-IPI, resulting in a Harrell's C index of 0.785 and area under the curve values of 0.863, 0.891, and 0.947 for the 1-, 2-, and 3-year PFS rates, respectively. Conclusion The corMTVsum offers significant prognostic value for patients with DLBCL. Furthermore, the combination of corMTVsum with the NCCN-IPI can provide an accurate prediction of the prognosis.

Anisotropy of Additively Manufactured Metallic Materials.

Additive manufacturing (AM) is a technology that builds parts layer by layer. Over the past decade, metal additive manufacturing (AM) technology has developed rapidly to form a complete industry chain. AM metal parts are employed in a multitude of industries, including biomedical, aerospace, automotive, marine, and offshore. The design of components can be improved to a greater extent than is possible with existing manufacturing processes, which can result in a significant enhancement of performance. Studies on the anisotropy of additively manufactured metallic materials have been reported, and they describe the advantages and disadvantages of preparing different metallic materials using additive manufacturing processes; however, there are few in-depth and comprehensive studies that summarize the microstructural and mechanical properties of different types of additively manufactured metallic materials in the same article. This paper begins by outlining the intricate relationship between the additive manufacturing process, microstructure, and metal properties. It then explains the fundamental principles of powder bed fusion (PBF) and directed energy deposition (DED). It goes on to describe the molten pool and heat-affected zone in the additive manufacturing process and analyzes their effects on the microstructure of the formed parts. Subsequently, the mechanical properties and typical microstructures of additively manufactured titanium alloys, stainless steel, magnesium-aluminum alloys, and high-temperature alloys, along with their anisotropy, are summarized and presented. The summary indicates that the factors leading to the anisotropy of the mechanical properties of metallic AM parts are either their unique microstructural features or manufacturing defects. This anisotropy can be improved by post-heat treatment. Finally, the most recent research on the subject of metal AM anisotropy is presented.

Changing trends in penile prosthesis implantation in China and an overview of postoperative outcomes from a single center.

BACKGROUND: Surgical penile prosthesis implantation (PPI) procedures have only recently been introduced to mainland China, with the overall number of such procedures having been conducted to date remaining relatively low. Accordingly, relatively little remains known with respect to the annual trends in PPI. Accordingly, this study was developed with the goal of clarifying these trends across different hospitals in mainland China, while also providing a single-center overview of post-PPI patient outcomes. RESULTS: To identify males in mainland China who had undergone PPI, a retrospective review of data from January 2019 - October 2023 was conducted. This approach revealed an increase in the total PPI caseload from 120 in 2019 to 413 within the first 10 months of 2023. Over this same interval, the number of surgeons performing PPI rose from 33 to 74. A retrospective review of the 112 patients who had undergone PPI at Shanghai General Hospital from 2019-2023 revealed that these patients had a median age of 39 [27-63] years, and PPI treatment led to a significant increase in median International Index of Erectile Function-5 (IIEF-5) scores from a baseline value of 10.23 ± 1.26 to a post-treatment value of 22.6 ± 2.73. The underlying causes of erectile dysfunction for these patients included vasculogenic factors (58/112; 51.8%), diabetes mellitus (21/112; 18.8%), and injuries to the spinal cord or pelvis (14/112; 12.5%). The overall rates of satisfaction with the PPI reported by patients and their partners were 93.0% and 90.4%, respectively, and the 3-year PPI survival rate for this cohort was 87%. CONCLUSION: These data highlight a rising trend in the number of PPI being performed in China, with these steadily increasing rates since 2019 emphasizing the increasingly high levels of acceptance of this procedure by patients and clinicians as a means of treating erectile dysfunction. However, the expertise is restricted to a small number of surgeons. Even so, it is a safe and efficacious approach to managing severe erectile dysfunction for patients in China, and when performed by experienced surgeons based on standardized protocols, low complication rates can be achieved while providing patients and their sexual partners with high levels of satisfaction.

RéSUMé: CONTEXTE: Les procédures chirurgicales d'implantation de prothèses péniennes (IPP) n'ont été que récemment introduites en Chine continentale, le nombre total de procédures de ce type ayant été effectuées à ce jour restant relativement faible. On ne sait donc encore que relativement peu de choses sur les tendances annuelles de l'IPP. La présente étude a été développée dans le but de clarifier ces tendances dans différents hôpitaux de Chine continentale, tout en fournissant une vue d'ensemble des résultats des patients post-IPP dans un seul centre. RéSULTATS: Afin d'identifier les hommes de Chine continentale qui avaient subi un IPP, une recherche rétrospective des données a été effectuée de janvier 2019 à octobre 2023. Cette approche a révélé une augmentation du nombre total de cas d'IPP de 120 en 2019 à 413 au cours des 10 premiers mois de 2023. Au cours de cette même période, le nombre de chirurgiens pratiquant des IPP est passé de 33 à 74. L'étude rétrospective des 112 patients qui avaient subi un IPP à l'hôpital général de Shanghai de 2019 à 2023 a révélé qu' ils avaient un âge médian de 39 [27­63] ans, et que le traitement par IPP a entraîné une augmentation significative des scores médians de l'indice international de la fonction érectile-5, qui sont passés d'une valeur de base de 10,2 ± 1,3 à une valeur post-traitement de 22,6 ± 2,7. Les causes sous-jacentes de la dysfonction érectile chez ces patients comprenaient des facteurs vasculogéniques (58/112; 51,8%), un diabète (21/112; 18,8%) et des lésions de la moelle épinière ou du bassin (14/112; 12,5%). Les taux globaux de satisfaction à l'égard de l'IPP, rapportés par les patients et leurs partenaires, étaient respectivement de 93,0% et 90,4%, et le taux de survie à 3 ans de l'IPP dans cette cohorte était de 87%. CONCLUSION: Ces données mettent en évidence une tendance à la hausse du nombre d'IPP pratiquées en Chine; ces taux en constante augmentation depuis 2019 soulignent les niveaux de plus en plus élevés d'acceptation de cette procédure par les patients et les cliniciens comme moyen de traitement de la dysfonction érectile. Cependant, l'expertise est limitée à un petit nombre de chirurgiens. Malgré cela, il s'agit d'une approche sûre et efficace pour gérer la dysfonction érectile sévère pour les patients en Chine, et lorsqu'elle est effectuée par des chirurgiens expérimentés sur la base de protocoles standardisés, de faibles taux de complications peuvent être atteints tout en offrant aux patients et à leurs partenaires sexuels des niveaux élevés de satisfaction.

RNA-binding protein IGF2BP1 is required for spermatogenesis in an age-dependent manner.

Post-transcriptional regulation mediated by RNA binding proteins is crucial for male germline development. Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1), an RNA binding protein, is specifically expressed in human and mouse male gonads and is involved in manifold biological processes and tumorigenesis. However, the function of IGF2BP1 in mammalian spermatogenesis remains poorly understood. Herein, we generated an Igf2bp1 conditional knockout mouse model using Nanos3-Cre. Germ cell deficiency of Igf2bp1 in mice caused spermatogenic defects in an age-dependent manner, resulting in decreased numbers of undifferentiated spermatogonia and increased germ cell apoptosis. Immunoprecipitation-mass spectrometry analysis revealed that ELAV-like RNA binding protein 1, a well-recognized mRNA stabilizer, interacted with IGF2BP1. Single cell RNA-sequencing showed distinct mRNA profiles in spermatogonia from conditional knockout versus wide type mice. Further research showed that IGF2BP1 plays a vital role in the modulation of spermatogenesis by regulating Lin28a mRNA, which is essential for clonal expansion of undifferentiated spermatogonia. Thus, our results highlight the crucial effects of IGF2BP1 on spermatogonia for the long-term maintenance of spermatogenesis.

Totally extraperitoneal laparoscopy-assisted microsurgical vasovasostomy for the treatment of obstructive azoospermia caused by pediatric bilateral inguinal herniorrhaphy.

BACKGROUND: Pediatric inguinal hernia repair (IHR) is a common cause of obstructive azoospermia (OA). Yet, the surgical treatment for this kind of OA remains difficult with poor fertility outcome. OBJECTIVES: To evaluate the safety and effectiveness of totally extraperitoneal laparoscopy-assisted microsurgical vasovasostomy (VV) in the treatment of OA caused by pediatric bilateral IHR. MATERIALS AND METHODS: Totally, 37 patients with OA caused by pediatric bilateral IHR were enrolled in this study from March 2015 to December 2020 in Shanghai General Hospital. The clinical data and fertility outcomes were collected and analyzed. RESULTS: All patients enrolled had a history of bilateral IHR at the age of 1-10 years old. The mean age of patients was 27 ± 4.31 (range: 18-35) years. Totally extraperitoneal laparoscopy (TEP) was applied in 31 patients for the exploration and retrieval of pelvic vas deferens end, and 30 of them underwent microsurgical VV successfully. Among the six cases where TEP was not applied, five cases underwent microsurgical anastomosis. Intraoperative exploration revealed that the location of vas deferens injuries included scrotum (2.70%, 1/37), inguinal canal (5.41%, 2/37), pelvic cavity (78.37%, 29/37), and multiple sites (13.51%, 5/37). The mean operation time was 339 ± 96.73 min (range: 130-510 min). There were no surgical complications. Thirty-three cases were followed up for 5-48 months with four cases lost to follow-up. The overall patency rate, pregnancy rate, and natural pregnancy rate were 75.86% (22/29), 46.67% (14/30), and 36.84% (7/19, 3 patients without family planning), respectively. And seven couples conceived through the assisted reproductive technique, two of which using fresh sperm in the ejaculate. CONCLUSION: TEP laparoscopy-assisted microscopic VV is an effective treatment for patients with OA caused by pediatric bilateral IHR.

Primate-Specific DAZ Regulates Translation of Cell Proliferation-Related mRNAs and is Essential for Maintenance of Spermatogonia.

Primate-specific DAZ (deleted in azoospermia) has evolved in the azoospermia factor c (AZFc) locus on the Y chromosome. Loss of DAZ is associated with azoospermia in patients with deletion of the AZFc region (AZFc_del). However, the molecular mechanisms of DAZ in spermatogenesis remain uncertain. In this study, the molecular mechanism of DAZ is identified, which is unknown since it is identified 40 years ago because of the lack of a suitable model. Using clinical samples and cell models, it is shown that DAZ plays an important role in spermatogenesis and that loss of DAZ is associated with defective proliferation of c-KIT-positive spermatogonia in patients with AZFc_del. Mechanistically, it is shown that knockdown of DAZ significantly downregulated global translation and subsequently decreased cell proliferation. Furthermore, DAZ interacted with PABPC1 via the DAZ repeat domain to regulate global translation. DAZ targeted mRNAs that are involved in cell proliferation and cell cycle phase transition. These findings indicate that DAZ is a master translational regulator and essential for the maintenance of spermatogonia. Loss of DAZ may result in defective proliferation of c-KIT-positive spermatogonia and spermatogenic failure.

scRNA-seq reveals that origin recognition complex subunit 6 regulates mouse spermatogonial cell proliferation and apoptosis via activation of Wnt/ß-catenin signaling.

ABSTRACT: The regulation of spermatogonial proliferation and apoptosis is of great significance for maintaining spermatogenesis. The single-cell RNA sequencing (scRNA-seq) analysis of the testis was performed to identify genes upregulated in spermatogonia. Using scRNA-seq analysis, we identified the spermatogonia upregulated gene origin recognition complex subunit 6 (Orc6), which is involved in DNA replication and cell cycle regulation; its protein expression in the human and mouse testis was detected by western blot and immunofluorescence. To explore the potential function of Orc6 in spermatogonia, the C18-4 cell line was transfected with control or Orc6 siRNA. Subsequently, 5-ethynyl-2-deoxyuridine (EdU) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays, flow cytometry, and western blot were used to evaluate its effects on proliferation and apoptosis. It was revealed that ORC6 could promote proliferation and inhibit apoptosis of C18-4 cells. Bulk RNA sequencing and bioinformatics analysis indicated that Orc6 was involved in the activation of wingless/integrated (Wnt)/ ß-catenin signaling. Western blot revealed that the expression of ß-catenin protein and its phosphorylation (Ser675) were significantly decreased when silencing the expression of ORC6. Our findings indicated that Orc6 was upregulated in spermatogonia, whereby it regulated proliferation and apoptosis by activating Wnt/ß-catenin signaling.

Deleterious variants in TAF7L cause human oligoasthenoteratozoospermia and its impairing histone to protamine exchange inducing reduced in vitro fertilization.

Introduction: Oligoasthenoteratozoospermia (OAT) is a major cause of infertility in males. Only a few pathogenic genes of OAT have been clearly identified till now. A large number of OAT-affected cases remain largely unknown. Methods: Here, Whole-exome sequencing (WES) in 725 idiopathic OAT patients was performed. Ejaculated spermatozoa by OAT patients were microinjected into mouse oocytes to estimate fertilization potential. Diff-quick staining and transmission electron microscopy were performed to evaluate sperm morphology and ultrastructure. The protein expression level and localization In vitro were detected by Western Blotting and Immunocytochemistry. Results: We identified four X-linked hemizygous deleterious variants of TAF7L-namely, c.1301_1302del;(p.V434Afs*5), c.699G>T;(p.R233S), c.508delA; (p. T170fs), c.719dupA;(p.K240fs) -in five probands. Intracytoplasmic sperm injection (ICSI) were carried out in M1, M2-1and M3 patient's wife. However only M1 patient's wife became pregnant after embryo transfer. In vitro study demonstrated significantly reduced fertilization ability in patient with TAF7L mutation. The TAF7L mutation let to abnormal sperm head and impaired histone-to protamine exchange. Variant 719dupA (p. K240fs) resulted in producing a truncated TAF7L protein and localized massively within the nucleus. In addition, TAF7L expression were not able to be detected due to variants c.1301_1302del (p. V434Afs*5) and c.508delA (p. T170fs) In vitro. Conclusion: Our findings support that TAF7L is one of pathogenic genes of OAT and deleterious mutations in TAF7L may cause impaired histone-to-protamine affected the chromatin compaction of sperm head.

Novel copy number variations within SYCE1 caused meiotic arrest and non-obstructive azoospermia.

BACKGROUND: Non-obstructive azoospermia (NOA) is the most severe disease in male infertility, but the genetic causes for majority of NOA remain unknown. METHODS: Two Chinese NOA-affected patients were recruited to identify the genetic causal factor of infertility. Whole-exome sequencing (WES) was conducted in the two patients with NOA. Sanger sequencing and CNV array were used to ascertain the WES results. Hematoxylin and eosin (H&E) staining and immunofluorescence (IF) were carried out to evaluate the stage of spermatogenesis arrested in the affected cases. RESULTS: Novel heterozygous deletion (LOH) within SYCE1 (seq[GRCh37] del(10)(10q26.3)chr10:g.135111754_135427143del) and heterozygous loss of function (LoF) variant in SYCE1 (NM_001143763: c.689_690 del:p.F230fs) were identified in one NOA-affected patient. While homozygous deletion within SYCE1 (seq[GRCh37] del(10)(10q26.3)chr10:g.135340247_135379115del) was detected in the other patient with meiotic arrest. H&E and IF staining demonstrated that the spermatogenesis was arrested at pachytene stage in the two patients with NOA, suggesting these two novel CNVs within SYCE1 could lead to meiotic defect and NOA. CONCLUSIONS: We identified that two novel CNVs within SYCE1 are associated with meiotic arrest and male infertility. Thus, our study expands the knowledge of variants in SYCE1 and provides a new insight to understand the genetic etiologies of NOA.

Novel Bi-Allelic Variants of FANCM Cause Sertoli Cell-Only Syndrome and Non-Obstructive Azoospermia.

Non-obstructive azoospermia (NOA) is the most severe disease in male infertility, but the genetic causes for the majority of NOA remain unknown. FANCM is a member of Fanconi Anemia (FA) core complex, whose defects are associated with cell hypersensitivity to DNA interstrand crosslink (ICL)-inducing agents. It was reported that variants in FANCM (MIM: 609644) might cause azoospermia or oligospermia. However, there is still a lack of evidence to explain the association between different FANCM variants and male infertility phenotypes. Herein, we identified compound heterozygous variants in FANCM in two NOA-affected brothers (c. 1778delG:p. R593Qfs*76 and c. 1663G > T:p. V555F), and a homozygous variant in FANCM (c. 1972C > T:p. R658X) in a sporadic case with NOA, respectively. H&E staining and immunohistochemistry showed Sertoli cell-only Syndrome (SCOS) in the three patients with NOA. Collectively, our study expands the knowledge of variants in FANCM, and provides a new insight to understand the genetic etiology of NOA.