13,14-seco withaphysalins from Physalis minima and their inhibitory effects on NLRP3 inflammasome activation.

Seven new 13,14-seco withaphysalins including two new skeletons (1 and 9) were isolated from the whole plants of Physalis minima, together with three known analogues (6-8). Among them, compound 1 was an extremely rare steroid with a 6, 8-cyclo ring. Their structures were established by extensive analysis of spectroscopic data, experimental electronic circular dichroism measurements, and single-crystal X-ray crystallographic analysis. In Raw264.7 cells, compounds 1-3, 5, 6, and 8 demonstrated potent ability to reduce the NLRP3-dependent caspase-1 activation. Among these compounds, 1 and 2 showed a superior potential, consistently concentration-dependent downregulating NLRP3-dependent proinflammatory cytokine IL-1ß production in macrophage. Mechanistically, compounds 1 and 2 reduced the cleavage of caspase-1 and GSDMD, and exhibited no obvious impact both on the NF-κB activation and the expression of NLRP3 and IL-1ß, suggesting that the compounds target the activation of the NLRP3 pathway mainly by inhibiting the NLRP3 inflammasome activation step rather than the priming step.

Anti-inflammatory germacrane-type sesquiterpene lactones from Vernonia sylvatica.

Nine new germacranolides, sylvaticalides A-H (1-9), and three known analogues (10-12) were isolated from the aerial part of Vernonia sylvatica. Their structures were established using comprehensive spectroscopic analysis, including high-resolution electrospray ionization mass spectroscopy (HR-ESI-MS) and 1D and 2D nuclear magnetic resonance (NMR) spectra. Their absolute configurations were determined by X-ray diffraction experiments. The anti-inflammatory activities of all isolated compounds were assessed by evaluating their inhibitory effects on the nuclear factor kappa B (NF-κB) pathway, which was activated by lipopolysaccharide (LPS)-stimulated human THP1-Dual cells, and the interferon-stimulated gene (ISG) pathway, activated by STING agonist MSA-2 in the same cell model. Compounds 1, 2 and 6 showed inhibitory effects on the NF-κB and ISG signaling pathways, with IC50 values ranging from 4.12 to 10.57 µmol·L-1.

Germacrane-type sesquiterpenes from Pilea cavaleriei Levl. subsp. cavaleriei.

The first systematic investigation of germacrane-type sesquiterpenes from Pilea cavaleriei Levl. subsp. cavaleriei was conducted. Eleven undescribed germacrane analogues named cavalinols A-K were identified. Their planar structures were determined by extensive analysis of 1D and 2D NMR spectroscopic data, and the absolute configurations were further determined by X-ray single crystal diffraction, Mosher method, and time dependent density functional theory (TDDFT) electron circular dichroism (ECD) calculation, with the aid from DFT NMR calculation and NOESY experiment. Except for the common 10-memebered ring, ten new compounds contained a p-coumaroyl sidechain connected to C-8 of the nucleus skeleton. All the isolated compounds were screened for anti-inflammatory activity in LPS stimulated RAW 264.7 cells, and compounds 5 and 6 showed moderate activity.

Enzymatic Synthesis of Noncanonical α-Amino Acids Containing γ-Tertiary Alcohols.

Noncanonical amino acids (ncAAs) containing tertiary alcohols are valuable as precursors of natural products and active pharmaceutical ingredients. However, the assembly of such ncAA scaffolds from simple material by C-C bond formation remains a challenging task due to the presence of multiple stereocenters and large steric hindrance. In this study, we present a novel solution to this problem through highly selective enzymatic decarboxylative aldol addition. This method allows for the streamlined assembly of multifunctionalized ncAAs with γ-tertiary alcohols from readily available materials, such as L -aspartatic acid and isatins, vicinal diones and keto esters. The modularity of electrophiles furnished four classes of ncAAs with decent efficiency as well as excellent site and stereocontrol. Computational modeling was employed to gain detailed insight into the catalytic mechanism and to provide a rationale for the observed selectivities. The method offers a single-step approach to producing multifunctionalized ncAAs, which can be directly utilized in peptide synthesis and bioactivity assessment.

Analysis of psychological crisis vulnerability among rural college students and its related factors / 中国学校卫生

Objective@#To understand vulnerability to psychological crisis among rural college students and its related factors, so as to provide reference for the prevention or intervention of psychological crisis among rural college students.@*Methods@#A total of 3 560 rural college students from grade one to grade three from five universities were selected using convenient cluster sampling method from January to September 2022 in Nanyang City. General information, vulnerability to psychological crisis, parenting style and Scale of Perceived Social Self efficacy (PSSE) were collected and analyzed through questionnaire.@*Results@#Among the investigated rule college students, the score of psychological crisis vulnerability and spoiling dimension of parenting style were (10.76± 3.46 ) points and (2.68±0.55) points, while the score of trust encouragement dimension of parenting style and PSSE were (2.52± 0.62 ) points and (3.29±0.61) points. Pearson correlation analysis showed that vulnerability to psychological crisis of rural students was positively correlated with spoiling and neglect ( r =0.32, 0.49), and was negatively correlated with trust encouragement, emotional warmth and PSSE ( r =-0.38, -0.53, -0.51)( P <0.05). Multiple linear regression analysis revealed that single parent family or other families, poor students, left behind experience, high score of spoiling and high score of neglect revealed high psychological crisis vulnerability ( P <0.05). High score of trust encouragement, high score of emotional warmth and PSSE were associated with low vulnerability to psychological crisis ( P <0.05).@*Conclusion@#Vulnerability to psychological crisis among rural college students is higher, which is related to the family structure, students whether they are poor, leftover experience, parenting style and PSSE. Mental health among rural college students should be promoted by strengthening communication with students parents and cultivating students social self efficacy.