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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.

Despite conservation tillage being a promising strategy to mitigate soil degradation, the intricate role of microbial communities in shaping soil quality over long‐term tillage remains poorly understood. The study aimed to investigate the microbial mechanisms governing the soil quality index (SQI) and maize yield under different tillage practices spanning 13 years, including no‐till without straw retention (NT0), no‐till with straw retention (NTSR), plough tillage with straw retention (PTSR), and rotary tillage with straw retention (RTSR). The findings revealed that NTSR improved the SQI index by 22.4% and 11.3% higher than PTSR and RTSR, respectively, within the 0–10 cm soil layer. This improvement was correlated with an increase in maize yield (R2 = 0.39, p < 0.05). PERMANOVA analysis confirmed that both soil depth and tillage practices significantly impacted the composition of microbial communities (p < 0.05). Furthermore, conservation tillage, compared to PTSR and RTSR, increased the abundance of arbuscular mycorrhizal symbiosis by 78.6%–460.3% but decreased the saprophytic fungal abundance by 27.5%–28.3%. Soil quality was notably influenced by the interaction between bacterial and fungal communities. The presence of bacterial‐dominated Module 2 was associated with decreased soil quality in the 0–10 cm soil depth (r = −0.47, p < 0.01). This study emphasizes the pivotal role of microbial diversity and dominant taxa in driving soil quality after long‐term conservation tillage practices. Understanding these mechanisms is crucial for establishing farmland management to achieve agricultural and ecological sustainability in the face of climate change and soil degradation challenges. [ABSTRACT FROM AUTHOR]

The number of patients with chronic kidney disease (CKD) is increasing. Oral toxin adsorbents may provide some value. Several uremic toxins, including indoxyl sulfate (IS), p‐cresol (PCS), acrolein, per‐ and poly‐fluoroalkyl substances (PFAS), and inflammation markers (interleukin 6 [IL‐6] and tumor necrosis factor [TNF]‐alpha) have been shown to be related to CKD progression. A total of 81 patients taking oral activated charcoal toxin adsorbents (AC‐134), which were embedded in capsules that dissolved in the terminal ileum, three times a day for 1 month, were recruited. The renal function, hemoglobulin (Hb), inflammation markers, three PFAS (PFOA, PFOS, and PFNA), and acrolein were quantified. Compared with the baseline, an improved glomerular filtration rate (GFR) and significantly lower acrolein were noted. Furthermore, the CKD stage 4 and 5 group had significantly higher concentrations of IS, PCS, IL‐6, and TNF but lower levels of Hb and PFAS compared with the CKD Stage 3 group at baseline and after the intervention. Hb was increased only in the CKD Stage 3 group after the trial (p =.032). Acrolein did not differ between the different CKD stage groups. Patients with improved GFR (responders) (about 77%) and nonresponders had similar baseline GFR. Responders had higher acrolein and PFOA levels throughout the study and a more significant reduction in acrolein, indicating a better digestion function. Both the higher PFOA and lower acrolein may be related to improved eGFR (and possibly to improvements in proteinuria, which we did not measure. Proteinuria is associated with PFAS loss in the urine), AC‐134 showed the potential to improve the GFR and decrease acrolein, which might better indicate renal function change. Future studies are needed with longer follow‐ups. [ABSTRACT FROM AUTHOR]

The equal molar AlCoCrFeNi high entropy alloys with 5% (volume fraction) TiB2 particles reinforcement were fabricated by spark plasma sintering (SPS). Effect of SPS temperature and pressure on microstructure evolution and mechanical properties of TiB2/AlCoCrFeNi composites was studied using X-raydiffraction (XRD), density testing, scanning electron microscopy (SEM) and mechanical properites testing. The results show that increasing SPS temperature and pressure can improve hardness and compressive strength of TiB2/AlCoCrFeNi composites. The relative density, compressive strength, yield strength and hardness of the TiB2/AlCoCrFeNi composite after sintering at 1200℃ and 30MPa are 99.6%, 2416MPa, 1474MPa and 470HB, respectively. During spark plasma sintering, phase transformation occurs in the high entropy alloy matrix of the composite. The composite after sintering at 1200℃ and 30-45MPa is composed of phases BCC, B2, FCC, TiB2 and σ.

In this study, to explore the effect of growth hormone changes on the related genes and regulatory roles of the turtle, PCR amplification, real-time fluorescence quantitative analysis, and enzyme cutting technology were used to clone and sequence the somatostatin (SS) gene, growth hormone receptor (GHR), and insulin-like growth factor-1 (IGF-I) sequence of Chinemys reevesii. The effects of human growth hormone on the mRNA expression of growth-axis-related genes SS, GHR, and IGF-1 in different sexes were observed. The study of the SS gene in turtles using real-time fluorescence quantitative PCR showed that the SS gene was mainly expressed in the nervous system and the digestive system, with the highest expression found in the brain, while the GHR gene and the IGF-I gene were expressed in all tissues of Chinemys reevesii. The SS gene was expressed in the brain, pituitary, liver, stomach, and intestine, with the highest expression in the brain and the lowest expression in the liver. Within 4 weeks of the injection of exogenous growth hormone, the expression level of the SS gene in the brain of both sexes first increased and then decreased, showing a parabolic trend, and the expression level of the experimental group was lower than that of the control group. After the injection of growth hormone (GH), the expression of the GHR gene in the liver of both sexes showed a significant increase in the first week, decreasing to the control group level in the second week, and then gradually increasing. Finally, a significant level of difference in the expression of the GHR gene was reached at 3 and 4 weeks. In terms of the IGF-I gene, the changing trend of the expression level in the liver was the same as that of the GHR gene. After the injection of exogenous growth hormone, although the expression of the SS gene increased the inhibition of the secretion of the GHR gene by the Reeves' turtle, exogenous growth hormone could replace the synthesis of GH and GHR, accelerating the growth of the turtle. The experiments showed that the injection of recombinant human growth hormone affects the expression of SS, GHR, and IGF-1 genes, and promotes the growth of the Reeves' turtle. [ABSTRACT FROM AUTHOR]