Octapeptin has strong antibacterial activity against Gram-negative bacteria such as Escherichia coli, Klebsiella pneumoniae and Acinetobacter baumannii, while it also has activity against some Gram-positive bacteria. This study used natural octapeptin A3 and B3 as lead compounds for structural modification. Twenty-one peptide derivatives (including A3 and B3) containing eight amino acid residues were prepared by solid-phase synthesis, and evaluated for antibacterial activity and renal cytotoxicity. Among them, three compounds 6, 7 and 17 exhibited broad-spectrum antibacterial activity and significantly enhanced the activity for Gram-positive bacteria while maintaining the activity of Gram-negative bacteria. Several compounds improved the activity for Pseudomonas aeruginosa. Compound 7 was active against all test strains and had relatively low renal cytotoxicity. The results provide a basis for the further development of novel polypeptide antibiotics.

177Lu-prostate specific membrane antigen(PSMA)radio-ligand therapy has been approved abroad for advanced prostate cancer and has been in several clinical trials in China.Based on domestic clinical practice and experimental data and referred to international experience and viewpoints,the expert group forms a consensus on the clinical application of 177Lu-PSMA radio-ligand therapy in prostate cancer to guide clinical practice.

The changes in epigenetic modifications of histones are one of the important factors in cancer development and metastasis,and the development of epigenetic therapies for cancer treatment has led to epigenetic drug screening as a research focus. In this work,the common methylation and acetylation modifications at the N-terminal of cellular histones H3 were quantified by a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method,and a throughput assay for screening and assessment of epigenetic drug was established. A total of 39 kinds of modification combinations containing common methylation and acetylation sites of H3 peptides were simultaneously monitored by triple quadrupole mass spectrometry in multiple reaction monitoring (MRM) mode. The developed method was applied to analyze HepG2 cells exposed for 24 h to 28 kinds of epigenetic drugs that could modulate the level of methylation or acetylation modifications. Results showed that 25 of these drugs,such as deacetylase inhibitors Abexinostat,Valproic acid and AGK7,induced histone H3 modification changes in the exposed cells that were consistent with those reported in the literature,while other modification changes were also detectable. Three of these drugs,including demethylase inhibitors IOX1,GSK-j1 and acetyltransferase inhibitor L002,however,induced modification changes different from those reported in the literature. An overall test match rate of 89.3％ was achieved. The established LC-MS/MS method could quantitatively analyze histone H3 modification sites and their changes in cells in a high-throughput and highly sensitive manner,and could be applied to the evaluation of epigenetic drugs with known activities,with good specificity and rich modification information,which was expected to provide a new technological tool for screening and evaluation of epigenetically active compounds and exploration of their mechanism of action.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Heart failure with preserved ejection fraction(HFpEF)may be a main form of heart failure,with a high mortality and an increasing incidence,which is a significant problem in cardiovascular disease.Although some important advancements in HFpEF has been made in recent years,its pathogenesis remains unclear,and the prognosis and mortality of patients have not significantly improved.Due to a large number of complications and complex pathological mechanism of HFpEF,and traditional treatment medicines of heart failure cannot effectively improve the prognosis of HFpEF patients,it is still lack of accurate diagnostic methods and effective clinical treatment strategies.Exploring and developing effective diagnostic and therapeutic approaches are of great clinical significance.This review summarizes the progress and future research direction in the diagnosis and treatment of HFpEF.

Sialic acid-binding immunoglobulin-like lectins(Siglecs)are expressed on most white blood cells and play a key role in signal transduction of immune cells.Recent studies have shown that many bacterial pathogens regulate the host immune response through the interaction between sialic acid(Sia)and Siglecs,thereby influencing the occurrence and development of diseases.Understanding bacterial pathogenic mechanisms is essential to identify potential effective therapeutic targets and help manage bacterial infectious diseases.Herein,the structure,biological function,and research progress in Siglecs in bacterial in-fectious diseases are briefly reviewed.

Aim To explore the effect of ginsenoside Rg3 on the biological behavior of human gastric cancer SGC-7901 cells by regulating E2F1.Methods MTT assay was used to determine the effect of ginsenoside Rg3(0,80,160,320 μmol·L-1)on cell prolifera-tion.The effects of different concentrations of ginsen-oside Rg3 on apoptosis were measured by flow cytome-try.The effects of different concentrations of ginsen-oside Rg3 on cell migration and invasion were deter-mined by scratch healing experiment and Transwell ex-periment.The effects of different concentrations of gin-senoside Rg3 on the expression of E2F1,MMP-2,MMP-9,BCL-2 and Bax were determined by Western blot.Results Compared with the blank control group,the cell survival rate of 80,160 and 320 μmol ·L-1 ginsenoside Rg3 group was significantly lower,and it was concentration-dependent(P＜0.05).Com-pared with the blank control group,the apoptosis rate of 80,160 and 320 μmol·L-1 ginsenoside Rg3 group significantly increased in a concentration-dependent manner(P＜0.05).Compared with the blank control group,the number of cell migration in 80,160 and 320 μmol·L-1 ginsenoside Rg3 groups was significantly lower in a concentration-dependent manner(P＜0.05).Compared with the blank control group,the number of cell invasion in 80,160 and 320 μmol· L-1 ginsenoside Rg3 groups was significantly lower in a concentration-dependent manner(P＜0.05).The E2F1 mRNA and E2F1 protein expression in the 80,160,and 320 μmol·L-1 ginsenoside Rg3 groups were significantly reduced in a concentration-dependent manner compared with that in the blank control group(P＜0.05).The protein expression of MMP-2,MMP-9,and BCL-2 in the cells of 80,160,and 320 μmol ·L-1 ginsenoside Rg3 group significantly decreased compared with those of the blank control group,and BCL-2 significantly increased compared with that of the blank control group in a concentration-dependent man-ner(P＜0.05).Conclusions Ginsenoside Rg3 can reduce the proliferation,inhibit the migration and inva-sion of gastric cancer SGC-7901 cells,and promote the apoptosis of SGC-7901 cells in a concentration-depend-ent manner,and its mechanism may be related to the down-regulation of MMP-2,MMP-9,and BCL-2 ex-pression and up-regulation of Bax expression through E2F1.

Objective:To investigate the effects of Xiongcan Yishen Formula(XYF)on ferroptosis in mouse TM3 Leydig cells after oxidative stress injury(OSI)induced by H2O2.Methods:An oxidative stress injury model was established in mouse TM3 Leydig cells using H2O2 induction.The modeled TM3 cells were randomly divided into OSI group,XYF group,the ferroptosis inhibitor Ferrostatin-1(F-1)group,and F-1+XYF group,which were respectively intervened with blank serum,20%drug-containing serum,2μmol/L F-1,and2μmol/L F-1+20%drug-containing serum.A control group(normal TM3 cells+blank serum)was also set up.The morphology of cells in each group was observed,and the levels of testosterone,superoxide dismutase(SOD),reactive oxygen spe-cies(ROS),malondialdehyde(MDA),ferritin heavy chain 1(FTH1),solute carrier family 7 member 11(SLC7A11),glutathione(GSH),glutathione peroxidase 4(GPX4),fatty acid CoA ligase 4(FACL4),total iron ions,and ferrous ions were detected.Re-sults:Compared with the model group,the control group showed significantly decreased expression of ROS,MDA,FACL4,total iron,and ferrous ions(P<0.05),and significantly increased levels of testosterone,SOD,GSH,FTH1,SLC7A11,and GPX4(P<0.05).The male silkworm kidney-tonifying formula group significantly promoted testosterone secretion by TM3 cells and upregulated the expression of FTH1,SLC7A11,GPX4,GSH,and SOD in TM3 cells(P<0.05),while significantly downregulating ROS,MDA,FACL4,total iron ions,and ferrous ions(P<0.05).Conclusion:Following H2O2 exposure,oxidative stress can induce ferroptosis in mouse TM3 Leydig cells.XYF can antagonize OSI and ferroptosis in TM3 cells by activating the SLC7A11/GSH/GPX4 axis,which may underlie the mechanism of XYF in the treatment of male late-onset hypogonadism.

Objective To investigate the effect and mechanism of astrocytes on the proliferation of neural stem cells (NSCs) in adult and juvenile hippocampus microenvironment. Methods Hippocampal astrocytes were isolated and cultured from 5 female SD rats at day 1 and week 30 postnatal, respectively; Embryonic hippocampus NSCs was isolated and cultured from 1 SD rat at day 15 of gestation; Conditioned astrocyte culture medium(CM) was collected for NSCs culture; Flow cytometry and CCK-8 were used to detect the proliferation of NSCs cultured in CM. Colony stimulating factor 1 (CSF-1) with differential expression was screened by mass spectrometry after cultured astrocyte CM. Western blotting and ELISA were used to verify the result of mass spectrometry. Immunofluorescence, flow cytometry and CCK-8 were used to detect the proliferation of NSCs treated with different concentrations of CSF-1 recombinant protein (20 μg/ L, 100 μg/ L, 1 mg/ L and 5 mg/ L). Results Compared with the adult group, the CM of hippocampal astrocytes in the young group could promote the proliferation of NSCs(P<0. 01); Compared with the conditioned medium of hippocampal astrocytes in the juvenile group, the expression of CSF-1 in the hippocampus of the elder group was significantly up-regulated(P<0. 01); At 20 μg/ L, CSF-1 promoted the proliferation of NSCs(P<0. 01), and 5 mg/ L CSF-1 inhibited significantly the proliferation of NSCs(P<0. 01). Conclusion The secretion of CSF-1 by astrocytes in hippocampal microenvironment can regulate the proliferation of NSCs with the development of the times.

Twelve compounds, including 5 new monoterpenes and 7 known derivatives, were isolated from a water decoction of Monochasma savatieri by column chromatography over macroporous adsorbent resin, MCI resin, Sephadex LH-20, and HW-40C, combined with preparative TLC, reversed phase HPLC, and flash column chromatographic techniques. Their structures were elucidated by comprehensive analysis of spectroscopic data, along with enzymatic hydrolysis as well as electronic circular dichroism (ECD) and NMR calculations, the new structures named monochaside I (1) and monochairidols A-D (2-5), respectively. The known compounds 6-12 were obtained from the Monochasma plants for the first time.