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The transition from spermatogonia to spermatocytes and the initiation of meiosis are key steps in spermatogenesis and are precisely regulated by a plethora of proteins. However, the underlying molecular mechanism remains largely unknown. Here, we report that Src homology domain tyrosine phosphatase 2 (Shp2; encoded by the protein tyrosine phosphatase, nonreceptor type 11 [Ptpn11] gene) is abundant in spermatogonia but markedly decreases in meiotic spermatocytes. Conditional knockout of Shp2 in spermatogonia in mice using stimulated by retinoic acid gene 8 (Stra8)-cre enhanced spermatogonial differentiation and disturbed the meiotic process. Depletion of Shp2 in spermatogonia caused many meiotic spermatocytes to die; moreover, the surviving spermatocytes reached the leptotene stage early at postnatal day 9 (PN9) and the pachytene stage at PN11-13. In preleptotene spermatocytes, Shp2 deletion disrupted the expression of meiotic genes, such as disrupted meiotic cDNA 1 (Dmc1), DNA repair recombinase rad51 (Rad51), and structural maintenance of chromosome 3 (Smc3), and these deficiencies interrupted spermatocyte meiosis. In GC-1 cells cultured in vitro, Shp2 knockdown suppressed the retinoic acid (RA)-induced phosphorylation of extracellular-regulated protein kinase (Erk) and protein kinase B (Akt/PKB) and the expression of target genes such as synaptonemal complex protein 3 (Sycp3) and Dmc1. Together, these data suggest that Shp2 plays a crucial role in spermatogenesis by governing the transition from spermatogonia to spermatocytes and by mediating meiotic progression through regulating gene transcription, thus providing a potential treatment target for male infertility.

The transition from spermatogonia to spermatocytes and the initiation of meiosis are key steps in spermatogenesis and are precisely regulated by a plethora of proteins. However, the underlying molecular mechanism remains largely unknown. Here, we report that Src homology domain tyrosine phosphatase 2 (Shp2; encoded by the protein tyrosine phosphatase, nonreceptor type 11 [Ptpn11] gene) is abundant in spermatogonia but markedly decreases in meiotic spermatocytes. Conditional knockout of Shp2 in spermatogonia in mice using stimulated by retinoic acid gene 8 (Stra8)-cre enhanced spermatogonial differentiation and disturbed the meiotic process. Depletion of Shp2 in spermatogonia caused many meiotic spermatocytes to die; moreover, the surviving spermatocytes reached the leptotene stage early at postnatal day 9 (PN9) and the pachytene stage at PN11–13. In preleptotene spermatocytes, Shp2 deletion disrupted the expression of meiotic genes, such as disrupted meiotic cDNA 1 (Dmc1), DNA repair recombinase rad51 (Rad51), and structural maintenance of chromosome 3 (Smc3), and these deficiencies interrupted spermatocyte meiosis. In GC-1 cells cultured in vitro, Shp2 knockdown suppressed the retinoic acid (RA)-induced phosphorylation of extracellular-regulated protein kinase (Erk) and protein kinase B (Akt/PKB) and the expression of target genes such as synaptonemal complex protein 3 (Sycp3) and Dmc1. Together, these data suggest that Shp2 plays a crucial role in spermatogenesis by governing the transition from spermatogonia to spermatocytes and by mediating meiotic progression through regulating gene transcription, thus providing a potential treatment target for male infertility.

Porous materials such as cellular cytosol, hydrogels, and block copolymers have nanoscale features that determine macroscale properties. Characterizing the structure of nanopores is difficult with current techniques due to imaging, sample preparation, and computational challenges. We produce a super-resolution optical image that simultaneously characterizes the nanometer dimensions of and diffusion dynamics within porous structures by correlating stochastic fluctuations from diffusing fluorescent probes in the pores of the sample, dubbed here as "fluorescence correlation spectroscopy super-resolution optical fluctuation imaging" or "fcsSOFI". Simulations demonstrate that structural features and diffusion properties can be accurately obtained at sub-diffraction-limited resolution. We apply our technique to image agarose hydrogels and aqueous lyotropic liquid crystal gels. The heterogeneous pore resolution is improved by up to a factor of 2, and diffusion coefficients are accurately obtained through our method compared to diffraction-limited fluorescence imaging and single-particle tracking. Moreover, fcsSOFI allows for rapid and high-throughput characterization of porous materials. fcsSOFI could be applied to soft porous environments such hydrogels, polymers, and membranes in addition to hard materials such as zeolites and mesoporous silica.

The human endometrium plays a vital role in providing the site for embryo implantation and maintaining the normal development and survival of the embryo. Recent studies have shown that stress is a common factor for the development of unexplained reproductive disorders. The nonreceptive endometrium and disturbed early maternal-fetal interaction might lead to infertility including the repeated embryo implantation failure and recurrent spontaneous abortion, or late pregnancy complications, thereby affecting the quality of life as well as the psychological status of the affected individuals. Additionally, psychological stress might also adversely affect female reproductive health. In recent years, several basic and clinical studies have tried to investigate the harm caused by psychological stress to reproductive health, however, the mechanism is still unclear. Here, we review the relationship between psychological stress and endometrial dysfunction, and its consequent effects on female infertility to provide new insights for clinical therapeutic interventions in the future.

Abstract. Proper development of the human placenta is of vital importance for a successful pregnancy, and a series of pregnancy complications are considered originating from dysfunctional placentas. Like other organ system development, placentation requires large numbers of co-regulators, while the underlying molecular mechanisms orchestrating the placental formation and function are poorly understood. Although we have made many signs of progress in understanding the placental architectures and developments using mouse models, the species-specific differences impede our progress due to the lack of appropriate model systems. In the past few years, major progress has been made by the establishment of novel in-vitro self-renewing stem cell models, as well as identifying the full picture of the cellular organization of the maternal and fetal interface. Providing the tools for the investigation of placentation and reproductive-related regulation mechanism. In this review, we focus on the detailed progress of the human trophoblast stem cells culturing system, and the cellular and molecular terrain at the maternal-fetal interface, respectively, thus providing new insights into placental development.

Objective: To evaluate the relation between the expression of PD‐1, PD‐L1, CD3, CD8, Foxp3 and clinicopathological features in patients with oral leukoplakia (OLK) and oral squamous cell carcinomas (OSCC) as well as the malignant outcome in OLK patients, and to study the effect of PD‐1 and PD‐L1 on immune microenvironment in the progression of oral carcinogenesis. Methods: We evaluated the expression of PD‐1/PD‐L1 and composition of CD3+, CD8+and Foxp3+ T lymphocytes in OLK and OSCC samples by immunohistochemical (IHC) staining and analyzed their relation with clinical information and malignant transformation in OLK patients. Results: IHC staining demonstrated that the expression of PD‐1 was significantly increased in the high‐grade OLK group than in the low‐grade OLK group, while PD‐L1 was detected mainly in OSCC. The expression of CD3, CD8, and Foxp3 was found higher in the high‐grade OLK group than in the low‐grade OLK group, and the Foxp3+ cells were found more in the OSCC group than in the high‐grade OLK group. PD‐1 was significantly correlated with CD3 (p < 0.05, R = 0.52), CD8 (p < 0.05, R = 0.46), and Foxp3 (p < 0.05, R = 0.46), and the low PD‐1‐expression group showed a better malignant‐free survival than high PD‐1 expression group in the OLK (p < 0.05). Conclusion: The PD‐1/PD‐L1 may induce immune suppression in OLK and accelerate the progress of malignant transformation. [ABSTRACT FROM AUTHOR]

In clinical practice, early pregnancy loss has afflicted approximately 15%–25% women of reproductive age worldwide, which is partially attributed to defects associated with the endometrium. During pregnancy, the endometrial stromal cells experience remarkable tissue remodeling and transformation, termed as decidualization, to support embryonic development, placental formation, and the maintenance of normal pregnancy in both mice and human. During this process, a series of dynamic developmental events, including rapid stromal proliferation, increased stromal cell size, enhanced angiogenesis, taken place in a highly-ordered manner under the precise regulation of steroid hormones. Meanwhile, diverse molecules exhibit spatiotemporal-specific expression pattern, implying their unique roles in decidual development. To achieve a more comprehensive understanding of these biological events and explore the underlying causes of early pregnancy disorders, this review emphasizes on the detailed developmental progression of decidual transformation and patterning as well as related pregnancy complications at the early stage of pregnancy.

Objective To discuss the methods and strategies to identify the causes of dependents’ deaths, as well as provide the experiences that can be used for reference and scientific basis for the forensic identification of the potentially growing deaths of the same kind in the future. Methods The 13 cases concerning death of dependents accepted by Sun Yat-sen University Forensic Center were collected, and the basic information of the dependents were statistically described. The nutritional status, environmental condition and medical care condition were evaluated according to dietary energy, living space, environment and medical treatment condition. Results Among the 13 dependents, there were 11 males and 2 females, with the oldest 74 and the youngest 9 and dwelling time was from 0.4 to 5.6 years. Forensic pathological examination showed that 13 dependents had infectious diseases and 11 were severely dystrophic. There were no fatal mechanical injuries or poisoning in dependents. Molecular pathological screening of 4 cases revealed no pathogenic variants of sudden death susceptible genes. The poor status of the diet, nutrition, living environment and medical care of these dependents were discovered. The direct cause of death of all 13 dependents was identified to be disease. The lack of nutrition, poor living environment and lack of medical care were thought to play a dominant role in causing the deaths of 12 dependants. Conclusion The death identification should follow the judicial procedure. In identification of the causes of death and analysis of the proportion of the affecting factors resulting in death, all factors, including nutrition,environment, medical care, injury and diseases, need to be considered.

A considerable amount of surplus nitrogen (N), which primarily takes the form of nitrate, accumulates in the soil profile after harvesting crops from an intensive production system in the North China Plain. The residual soil nitrate (RSN) is a key factor that is included in the N recommendation algorithm. Quantifying the utilization and losses of RSN is a fundamental necessity for optimizing crop N management, improving N use efficiency, and reducing the impact derived from farmland N losses on the environment. In this study, a 15N-labeling method was introduced to study the fate of the RSN quantitatively during the winter wheat growing season by 15N tracer technique combined with a soil column study. A soil column with a 2 m height was vertically divided into 10 20-cm layers, and the RSN in each layer was individually labeled with a 15N tracer before the wheat was sown. The results indicated that approximately 17.68% of the crop N derived from RSN was located in the 0-2 m soil profile prior to wheat sowing. The wheat recovery proportions of RSN at various layers ranged from 0.21% to 33.46%. The percentages that still remained in the soil profile after the wheat harvest ranged from 47.08% to 75.44%, and 19.46-32.64% of the RSN was unaccounted for. Upward and downward movements in the RSN were observed, and the maximum upward and downward distances were 40 cm and 100 cm, respectively. In general, the 15N-labeling method contributes to a deeper understanding of the fates of the RSN. Considering the low crop recovery of the RSN from deep soil layers, water and N saving practices should be adopted during crop production.

This paper proposes a new measure for recommendation through integrating Triangle and Jaccard similarities. The Triangle similarity considers both the length and the angle of rating vectors between them, while the Jaccard similarity considers non co-rating users. We compare the new similarity measure with eight state-of-the-art ones on four popular datasets under the leave-one-out scenario. Results show that the new measure outperforms all the counterparts in terms of the mean absolute error and the root mean square error.

This study aimed to evaluate the effects of di-(2-ethylhexyl) phthalate (DEHP) on estrous cycle, sex hormone levels and ovary histological features. A total of 80 female SD rats were randomly divided into 8 groups (n=10 per group): short-course control group, short-course low-dose group, short-course medium-dose group, and short-course high-dose group, long-course control group, long-course low-dose group, long-course medium-dose group and longcourse high-dose group. Intragastrical DEHP was administrated at 1000 mg/kg/d (low dose), 2000 mg/kg/d (medium dose) and 3000 mg/kg/d (high dose) independently for 14 days (short course) or 28 days (long course). Rats in control groups were untreated. Vaginal smearing was used to detect the estrous cycle and rats were weighed at every Monday and Thursday to evaluate the growth status. At the end of study, rats were sacrificed and bilateral ovaries were obtained for histological examination. In addition, ELISA determined levels of serum progesterone, estradiol, testosterone, follicle stimulating hormone and luteinizing hormone. DEHP treatment limited body weight gain (P

The first genome-wide association study for coronary artery disease (CAD) in the Han Chinese population, we reported recently, had identified rs6903956 in gene ADTRP on chromosome 6p24.1 as a novel susceptibility locus for CAD. The risk allele of rs6903956 was associated with decreased mRNA expression of ADTRP. To further study the correlation of ADTRP expression and CAD, in this study we evaluated the associations of eight common variants in the expression-regulating regions of ADTRP with CAD in the Southern Han Chinese population. Rs169790 in 3'UTR, rs2076189 in 5'UTR, four SNPs (rs2076188, rs7753407, rs11966356 and rs1018383) in promoter, and two SNPs (rs3734273, rs80355771) in the last intron of ADTRP were genotyped in 1716 CAD patients and 1572 controls. The correlations between these loci and total or early-onset CAD were investigated. None of these loci was discovered to associate with total CAD (P > 0.05). However, with early-onset CAD, significant both allelic and genotypic associations of rs7753407, rs11966356 and rs1018383 were identified, after adjustment for risk factors of age, gender, hypertension, diabetes, lipid profiles and smoking (adjusted P < 0.05). A haplotype AGCG (constructed by rs2076188, rs7753407, rs11966356 and rs1018383) was identified to protect subjects from early-onset CAD (OR = 0.332, 95% CI = 0.105-0.879, adjusted P = 0.010). Real-time quantitative reverse transcription polymerase chain reaction assay showed that the risk alleles of the associated loci were significantly associated with decreased expression of ADTRP mRNA. Moreover, the average level of ADTRP mRNA expression in early-onset CAD cases was significantly lower than that in controls. Our results provide new evidence supporting the association of ADTRP with the pathogenesis of early-onset CAD.