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Objective To establish a mouse model treated with busulfan and to investigate its effects on the metabolism of spermatogonial stem cells (SSCs) of mouse testis. Methods C57BL/6J male mice with age of 8 weeks were injected with 10 mg/kg of busulfan intraperitoneally, then Thy1 positive cells were selected by immunomagnetic beads on day 0, day 5 and day 10 and followed by identification for purity and metabolomic analysis. ResultsThe testis weight ratio decreased and the tissue structure of testis was damaged (P＜0.05). Based on the results of principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) , there were significant metabolic differences between the sample groups treated for 0 d, 5 d and 10 d. A total of 89 differential metabolites were identified including glutathione (GSH), arginine and unsaturatedfatty acids (UFAs), and their important metabolic pathways involved glycerophospholipid metabolism, arginine and proline metabolism. Conclusions Affecting the specific metabolic pathway may result in obvious reproductive toxicity and lead to decrease of testicular weight as well as tissue structure damage in mice. Metabolomic analysis showed that the potential reproductive toxicity mechanism of SSCs may be related to the metabolic pathways such as lipid metabolism, arginine and proline metabolism.

Elucidating the mechanical forces between two solid surfaces immersed in a communal liquid environment is crucial for understanding and controlling adhesion, friction, and electrochemistry in many technologies. Although traditional models can adequately describe long-range mechanical forces, they require substantial modifications in the nanometric region where electronic effects become important. A hybrid quantum–classical model is employed herein to investigate the separation-dependent disjoining pressure between two metal surfaces immersed in an electrolyte solution under potential control. We find that the pressure between surfaces transits from a long-range electrostatic interaction, attractive or repulsive depending on the charging conditions of surfaces, to a strong short-range van der Waals attraction and then an even strong Pauli repulsion due to the redistribution of electrons. The underlying mechanism of the transition, especially the attractive–repulsive one in the short-range region, is elucidated. This work contributes to the understanding of electrotunable friction and lubrication in a liquid environment. [ABSTRACT FROM AUTHOR]

Objective To explore the physiological function of gene for cell devision cycle associated 2 (Cdca2), a highly expressed testis gene, in spermatogenesis and fertility in mice. Methods The expression of Cdca2 in different tissues of mice was detected by Q-PCR and Western blot; Using CRISPR/Cas9 gene editing technology and Cre-loxP mediated recombination system, a mouse strain with Cdca2 tissue specific knockout was constructed; By hematoxylin-eosin(HE) staining and morphological analysis, the effect of CDCA2 deletion on spermatogenic cell morphology at different stages of spermatogenesis was studied; The effects of CDCA2 deletion on sperm motility and motility parameters were detected by an automatic sperm detection and analysis system; The effect of CDCA2 deletion on the fertility of male mice was examined by fertility test. Results Cdca2 was a highly expressed gene in testis; Cdca2 germ cell specific knockout mice were successfully obtained by CRISPR/Cas9 technology and reproductive system; CDCA2 deletion in mice had no statistically significant effect on spermatogenic cells, sperm motility parameters and male fertility at all stages of spermatogenesis. Conclusions Cdca2 is probably not necessary for spermatogenesis and male fertility maintenance in mice.

Objective To investigate the role of cytoplasmic poly (A) binding protein-6 (PABPC6) in spermatogenesis of male mice. Methods The Pabpc6 in C57BL/6J mice was knocked out by CRISPR/Cas9 targeting, and the Pabpc6 was identified by PCR. Three types of mice with different genotypes of Pabpc6+/+, Pabpc6+/- and Pabpc6-/- were obtained by mating and breeding. Testis was weighed;Morphological observation and sperm counting were carried out. The mRNA and protein expression levels of Pabpc6 in different tissues were detected by real-time quantitative PCR and Western blot. Immunofluorescence and hematoxylin-eosin staining were used to observe the location of the gene and the morphological changes in the convoluted spermatic tubule of testis. Results The Pabpc6 knockout mice were successfully identified. Pabpc6 was highly expressed in testicular tissue(P＜0.001). Immunofluorescence showed that Pabpc6 was mainly expressed in spermatocyte at early sperm stage. Compared with wild-type mice, knockout mice showed no significant differences in testicular shape, sperm morphology, sperm count and the morphology of convoluted spermatic ducts. Conclusions Pabpc6 is found to be highly expressed in the testis tissue of mice. Pabpc6 has no obvious effect on spermatogenesis of male mice after knockout of Pabpc6. The results indicate that the protein encoded by Pabpc6 is not necessary for spermatogenesis of mice.

[Objective] Ecological restoration has become the main component and important content of ecological civilization construction. However, with the continuous expansion and in-depth development of ecological restoration work, the issue of misalignment of ecological restoration practices has emerged. This urgently requires attention and effective solutions to ensure the sustainable development of ecological restoration practices in China. [Methods] Based on the theoretical research on ecological restoration and by clarifying its connotation and goals, this study defined the connotation of misalignment of ecological restoration practices. It also examined the basis for the identification of ecological restoration misalignment, summarized the main types of ecological restoration misalignment in China, analyzed the reasons for the misalignment of ecological restoration, and put forward suggestions for correcting the misalignment of ecological restoration. [Results] The results show that the main types of ecological restoration misalignment in China include violation of the basic theory of ecological restoration, deviation from the connotation of ecological restoration goals, and inappropriate planning and implementation of ecological restoration projects. The main reasons for the misalignment of ecological restoration are incorrect conceptual understanding, insufficient grasp of patterns and mechanisms, insufficient integration of theory and practice, and inappropriate implementation in practice. [Conclusion] In the future, the misalignment of ecological restoration should be dealt with from the following four aspects: establishing correct ecological civilization concepts, understanding the patterns and mechanisms of the ecosystem, integrating theory and practice, and improving the implementation of ecological restoration projects. Promoting the ecological restoration of the national territorial space also needs to adopt diversified strategies.

The liquid‐phase mass transport is the key factor affecting battery stability. The influencing mechanism of liquid‐phase mass transport in the separators is still not clear, the internal environment being a complex multi‐field during the service life of lithium‐ion batteries. The liquid‐phase mass transport in the separators is related to the microstructure of the separator and the physicochemical properties of electrolytes. Here, in‐situ local electrochemical impedance spectra were developed to investigate local inhomogeneities in the mass transfer process of lithium‐ion batteries. The geometric microstructure of the separator significantly impacts the mass transfer process, with a reduction in porosity leading to increased overpotentials. A competitive relationship among porosity, tortuosity, and membrane thickness in the geometric parameters of the separator were established, resulting in a peak of polarization. The resistance of the liquid‐phase mass transfer process is positively correlated with the viscosity of the electrolyte, hindering ion migration due to high viscosity. Polarization is closely related to the electrochemical performance, so a phase diagram of battery performance and inhomogeneous mass transfer was developed to guide the design of the battery. This study provides a foundation for the development of high stability lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Five new cembrane-type diterpenes, lobocalines A–E (1–5), and four new steroids, lobocaloids A–D (9–12), along with six known related compounds (6–8 and 13–15) were isolated from the Yalong Bay soft coral Lobophytum catalai Tixier-Durivault. The structures of the new compounds were elucidated by extensive spectroscopic analysis, NMR calculation with DP4+ analysis, time-dependent density functional theory–electronic circular dichroism (TDDFT-ECD) calculations, X-ray diffraction analyses and comparison with the reported spectroscopic data of known compounds. Further, with the aid of X-ray diffraction analysis, the structure of lobocrasol B (15) was firmly revised as 15a. In in vitro bioassays, compound 2 showed moderate antibacterial activities against fish pathogenic bacteria Streptococcus parauberis KSP28 and Phoyobacterium damselae FP2244 with minimum inhibitory concentration (MIC) values of 8.7 and 17.3 µg/mL, respectively. All the steroids exhibited antibacterial activities against the S. parauberis KSP28 with MIC values ranging from 12.3 to 53.6 µg/mL. Compounds 2, 7 and 14 have remarkable inhibitory effects on the hemolysin production of Staphylococcus aureus, while compounds 8–12 have medium inhibitory effects on the pyocyanin production in Pseudomonas aeruginosa.

Three new cembranoids (1–3) and a new casbanoid (4), along with three known analogues (5–7), have been isolated from the soft coral Sinularia nanolobata collected off Ximao Island. The structures, including the absolute configurations of new compounds, were established using extensive spectroscopic data analysis, time-dependent density functional theory/electronic circular dichroism (TDDFT-ECD) calculations, and the comparison with spectroscopic data of known compounds. In the in vitro bioassay, compounds 1 and 5 exhibited moderate cytotoxic activities against human erythroleukemia (HEL) cell lines, with IC50 values of 37.1 and 42.4 μM, respectively.

Objective To investigate the application of CRISPR/CasRx mediated gene knockdown at the RNA level in mouse spermatogonia cell line GC1-spg. Methods The EF1a core promoter. CasRx.SV40.U6.DRs expression plasmid (CasRx-gRNA) and three fluorescent protein of EF1a.EGFP, EF1a.mCherry, EF1a.tdToamto expression plasmids were constructed by homologous recombination. Three fluorescent protein expression plasmids and CasRx-gRNA expression plasmids were transiently transfected into human embryonic kidney cell line HEK-293T, and the knockdown of exogenous gene (the fluorescent proteins,EGFP and mCherry) was used to detect by fluorescence intensity and Western blot. Additionally, the expression levels of endogenous gene (mRNA and lncRNA) were measured by q-PCR in HEK-293T cells transfected with CasRx-gRNA. The exogenous gene egfp, mCherry and CasRx-gRNA expression plasmids were transiently transfected into the mouse spermatogonia cell line GC1, and the knockdown efficiency of exogenous gene (the fluorescent proteins) was detected by the above method. Results CasRx-gRNA and three kinds of fluorescent protein expression plasmids were constructed successfully. After CRISPR/CasRx mediated RNA interference of exogenous genes (egfp, mCherry) and endogenous genes (mRNA, lncRNA) in HEK-293T cells, the expression level was significantly reduced (P＜0.01). The CRISPR/CasRx system was verified in the mouse spermatogonia cell line GC1, which could effectively and specifically knock down exogenous genes egfp and mCherry. Conclusions CRISPR/CasRx system exerts an effective and specific knock-down function in GC1-spg, providing a new gene silencing tool potentially used in the study of male reproduction.

Nonaqueous organic aluminum batteries are considered as promising high‐safety energy storage devices due to stable ionic liquid electrolytes and Al metals. However, the stability and capacity of organic positive electrodes are limited by their inherent high solubility and low active organic molecules. To address such issues, here porphyrin compounds with rigid molecular structures present stable and reversible capability in electrochemically storing AlCl2+. Comparison between the porphyrin molecules with electron‐donating groups (TPP‐EDG) and with electron‐withdrawing groups (TPP‐EWG) suggests that EDG is responsible for increasing both highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels, resulting in decreased redox potentials. On the other hand, EWG is associated with decreasing both HOMO and LUMO energy levels, leading to promoted redox potentials. EDG and EWG play critical roles in regulating electron density of porphyrin π bond and electrochemical energy storage kinetics behavior. The competitive mechanism between electrochemical redox reaction and de/adsorption processes suggests that TPP‐OCH3 delivers the highest specific capacity ~171.8 mAh g−1, approaching a record in the organic Al batteries. [ABSTRACT FROM AUTHOR]

Abstract A phytochemical investigation of the EtOH extract of the flowers of Lagerstroemia indica L. led to the isolation and characterization of a new pyrrole alkaloid, named lagerindicine (1), along with four known compounds (2–5). Their structures were elucidated by the detailed spectroscopic analysis and comparison with literature data, whereas the structure, in particularly, the absolute configuration (AC) of 1, was firmly determined by total synthesis. All the isolates were evaluated for their cytotoxic effects against human colon cancer cell (HCT-116), and compound 3 exhibited weak cytotoxicity with IC50 value of 28.4 μM. Graphic Abstract