Antibiotic adjuvants offer a promising strategy for restoring antibiotic sensitivity, expanding antibacterial spectra, and reducing required dosages. Previously, compound 15 was identified as a potential adjuvant for Polymyxin B (PB) against multidrug-resistant (MDR) Pseudomonas aeruginosa DK2; however, its clinical utility was hindered by high cytotoxicity, uncertain in vivo efficacy, and an unclear synergetic mechanism. To address these challenges, we synthesized and evaluated a series of novel benzamide derivatives, with A22 emerging as a particularly promising candidate. A22 demonstrated potent synergistic activity to PB, minimal cytotoxicity, improved water solubility, and broad-spectrum synergism of polymyxins against various clinically isolated MDR Gram-negative strains. In vivo studies using Caenorhabditis elegans and mouse models further confirmed the efficacy of A22. Moreover, A22 effectively suppressed the development of PB resistance in Pseudomonas aeruginosa DK2. Mechanistic investigations revealed that A22 enhances polymyxins activity by inducing reactive oxygen species production, reducing ATP levels, increasing NOX activity, and inhibiting biofilm formation, leading to bacterial death. These findings position A22 as a highly promising candidate for the development of polymyxin adjuvants, offering a robust approach to combating MDR Gram-negative bacterial infections.

OBJECTIVES: To investigate the effects of quercetin on cuproptosis and L-type calcium currents in the myocardium of diabetic rats. METHODS: Forty SD rats were randomized into control group and diabetic model groups. The rat models of diabetes mellitus (DM) induced by high-fat and high-sugar diet combined with streptozotocin (STZ) injection were further divided into DM model group, quercetin treatment group, and empagliflozin treatment group (n=10). Blood glucose and body weight were measured every other week, and cardiac function of the rats was evaluated using echocardiography. HE staining, Sirius red staining, and wheat germ agglutinin (WGA) analysis were used to observe the changes in myocardial histomorphology, and serum copper levels and myocardial FDX1 expression were detected. In cultured rat cardiomyocyte H9c2 cells with high-glucose exposure, the effects of quercetin and elesclomol, alone or in combination, on intracellular CK-MB and LDH levels and FDX1 expression were assessed, and the changes in L-type calcium currents were analyzed using patch-clamp technique. RESULTS: The diabetic rats exhibited elevated blood glucose, reduced body weight, impaired left ventricular function, increased serum copper levels and myocardial FDX1 expression, decreased L-type calcium currents, and prolonged action potential duration. Quercetin and empagliflozin treatment significantly lowered blood glucose, improved body weight, and restored cardiac function of the diabetic rats, and compared with empagliflozin, quercetin more effectively reduced serum copper levels, downregulated FDX1 expression, and enhanced myocardial L-type calcium currents in diabetic rats. In H9c2 cells, high glucose exposure significantly increased myocardial expressions of FDX1, CK-MB and LDH, which were effectively lowered by quercetin treatment; Elesclomol further elevated FDX1, CK-MB and LDH levels in the exposed cells, and these changes were not significantly affected by the application of quercetin. CONCLUSIONS Quercetin ameliorates myocardial injury in diabetic rats possibly by suppressing myocardial cuproptosis signaling and restoring L-type calcium channel activity.
Animals ; Quercetin/pharmacology* ; Calcium Channels, L-Type/metabolism* ; Diabetes Mellitus, Experimental/metabolism* ; Rats, Sprague-Dawley ; Rats ; Myocytes, Cardiac/drug effects* ; Myocardium/pathology* ; Male

Given the increasing concern regarding antibacterial resistance, the antimicrobial properties of naphthoquinones have recently attracted significant attention. While 1,4-naphthoquinone and its derivatives have been extensively studied, the antibacterial properties of 5,8-dihydroxy-1,4-naphthoquinone derivatives remain relatively unexplored. This study presents a comprehensive in vitro and in vivo analysis of the antibacterial activity of 35 naturally sourced and chemically synthesized derivatives of 5,8-dihydroxy-1,4-naphthoquinone. Kirby-Bauer antibiotic testing identified three compounds with activity against methicillin-resistant Staphylococcus aureus (MRSA), with one compound (PNP-02) demonstrating activity comparable to vancomycin in minimum inhibitory concentration, minimum bactericidal concentration (MBC), and time-kill assays. Microscopic and biochemical analyses revealed that PNP-02 adversely affects the cell wall and cell membrane of MRSA. Mechanistic investigations, including proteomic sequencing analyses, Western blotting, and RT-qPCR assays, indicated that PNP-02 compromises cell membrane integrity by inhibiting arginine biosynthesis and pyrimidine metabolism pathways, thereby increasing membrane permeability and inducing bacterial death. In an in vivo mouse model of skin wound healing, PNP-02 exhibited antibacterial efficacy similar to vancomycin. The compound demonstrated low toxicity to cultured human cells and in hemolysis assays and remained stable during serum incubation. These findings suggest that PNP-02 possesses promising bioactivity against MRSA and represents a potential novel antibacterial agent.
Methicillin-Resistant Staphylococcus aureus/genetics* ; Anti-Bacterial Agents/chemistry* ; Naphthoquinones/administration & dosage* ; Animals ; Microbial Sensitivity Tests ; Mice ; Humans ; Staphylococcal Infections/microbiology* ; Molecular Structure

Objective Establish the method of bacterial endotoxins test for human papillomavirus bivalent(types 16,18)vaccine(pichia pastoris).Methods The method of gel-clot technique and photometric technique(kinetic-turbidimetric assay and kinetic-chromogenic assay)for the determination of bacterial endotoxins was carried out according to the Appendix of China Pharmacopoeia in 2020 Vol Ⅲ 1143"bacterial endotoxins test"and Vol IV 9251"guidelines for bacterial endotoxin test".Results There is no interference after more than forty times dilution for gel-clot technique,the recovery rates of kinetic-turbidimetric assay and kinetic-chromogenic assay can also meet the requirements.Conclusion It is feasible to establish gel-clot technique,kinetic-turbidimetric assay and kinetic-chromogenic assay for bacterial endotoxin test of human papillomavirus bivalent(types 16,18)vaccine(pichia pastoris).

Objective:To further improve the understanding of paroxysmal nocturnal hemoglobinuria (PNH), we retrospectively analyzed and summarized the clinical characteristics, treatment status, and survival status of patients with PNH in Zhejiang Province.Methods:This study included 289 patients with PNH who visited 20 hospitals in Zhejiang Province. Their clinical characteristics, comorbidity, laboratory test results, and medications were analyzed and summarized.Results:Among the 289 patients with PNH, 148 males and 141 females, with a median onset age of 45 (16-87) years and a peak onset age of 20-49 years (57.8% ). The median lactic dehydrogenase (LDH) level was 1 142 (604-1 925) U/L. Classified by type, 70.9% (166/234) were classical, 24.4% (57/234) were PNH/bone marrow failure (BMF), and 4.7% (11/234) were subclinical. The main clinical manifestations included fatigue or weakness (80.8%, 235/289), dizziness (73.4%, 212/289), darkened urine color (66.2%, 179/272), and jaundice (46.2%, 126/270). Common comorbidities were hemoglobinuria (58.7% ), renal dysfunction (17.6% ), and thrombosis (15.0% ). Moreover, 82.3% of the patients received glucocorticoid therapy, 70.9% required blood transfusion, 30.7% used immunosuppressive agents, 13.8% received anticoagulant therapy, and 6.3% received allogeneic hematopoietic stem cell transplantation. The 10-year overall survival (OS) rate was 84.4% (95% CI 78.0% -91.3% ) . Conclusion:Patients with PNH are more common in young and middle-aged people, with a similar incidence rate between men and women. Common clinical manifestations include fatigue, hemoglobinuria, jaundice, renal dysfunction, and recurrent thrombosis. The 10-year OS of this group is similar to reports from other centers in China.

Objective To provide some evidence for early empirical treatment of infections caused by Pseudanonas aeruginosa(PA)and establish a certain foundation for further studies on its resistance mechanisms.Analyzed the resistance rate of PA and the phenotype characteristics for seven years at this hospital.Methods Using Whonet 5.6 software,the drug sensitivity data of PA isolated and reported from clinical specimens at Kunming First People's Hospital from 2016 to 2022 were analyzed annually.Imipenem,meropenem,ceftazidime,and cefepime were the main observation objects,statisticaly analyze the resistance of other antibiotics under different drug resistance combinations of the above-mentioned drugs Results A total of 1 920 strains of PA were detected in 7 years,with polymyxins exhibiting the lowest resistance rate at 1%.The average resistance rates for Amikacin,Gentamicin and Tobramycin were 6.4%,8.6%and 5.1%,respectively.The resistance rates of Quinolones,Piperacillin/Tazobactam,Ceftazidime,and Cefepime were similar,ranging from 10%～20%.Imipenem and Meropenem did not show better sensitivity,with resistance rates of 21.3%and 18.4%,respectively.The resistance rates of major antibiotics have fluctuated over the past 7 years,mostly increasing from 2017 to reaching a peak in 2018 and then falling back.And then stabilized with the domestic average level.1 393 strains were sensitive to Imipenem,and the sensitivity rate of Meropenem in this part was 96.2%.1 451 strains were sensitive to Imipenem,and 89%of them were sensitive to Meropenem at the same time.369 strains were both resistant to Imipenem and Meropenem,and 33.1%of them were sensitive to Ceftazidime.The more resistant to β-lactam,the lower the sensitivity rate to Amikacin and Ciprofloxacin.Conclusion The overall drug sensitivity of PA in this hospital is relatively good.Should adhere to strict management of antibiotic use.Aminoglycosides can be the preferred drugs for empirical treatment,followed by Quinolones,and Carbapenems and Ceftazidime are also candidates.PA has diverse resistance mechanisms to β-lactam antimicrobials,and carbapenem-resistant strains can be mediated by different mechanisms or jointly.

Objective:To explore the mediating effect of hospice self-efficacy among clinical nurses between sense of life meaning and hospice behavior, in order to provide references for nursing managers to formulate strategies to improve clinical nurses′ hospice behavior.Methods:This was a cross-sectional survey study. The clinical nurses were selected from 8 tertiary hospitals in Ningxia Hui Autonomous Region by convenience sampling method from July to November in 2023. General data survey scale, The Meaning in Life Questionnaire, End-of-life Care Self-efficacy Scale and Hospice Behavior Scale were used to investigate. Pearson correlation analysis was used to examine the correlation between variables, and AMOS 24.0 software was used to analyze the mediating effect of hospice self-efficacy on nurses′ sense of meaning of life and hospice behavior.Results:The effective response rate of the questionnaire was 89.82%(988/1 100). There were 41 males and 947 females, aged (32.95 ± 5.61) years old. The scores of sense of life meaning, end-stage hospice self-efficacy and hospice behavior of clinical nurses were (45.18 ± 7.90), (49.62 ± 10.93), (123.42 ± 28.55) points, respectively. Correlation analysis showed that the sense of life meaning, hospice behavior and end-stage hospice self-efficacy of clinical nurses were correlated ( r values were 0.263-0.932, all P<0.01). The terminal hospice self-efficacy had a partial mediating effect between clinical nurses′ sense of life meaning and hospice behavior.The total effect of the sense of life meaning on clinical nurses′ hospice care behavior was 0.435, in which the direct effect was 0.246, accounting for 56.55% of the total effect, the indirect effect was 0.190, accounting for 43.45% of the total effect. Conclusions:End-stage hospice self-efficacy of clinical nurses is the mediating variable between sense of life meaning and hospice behavior. Managers can improve hospice behavior by cultivating end-stage hospice self-efficacy of clinical nurses.

Objective To investigate the effect of melanoma associated antigen D1 (Mage-D1)on mouse femoral bone mass and mineralization ability of mouse bone marrow mesenchymal cells (BMSCs)and its potential molecular mechanism.Methods Female Mage-D1 gene knockout heterozygous mice and male wild-type (WT)mice were subjected as parent mice to breed Mage-D1 gene knockout homozygous (Mage-D1 KO)mice.PCR and agarose gel electrophoresis were used to identify male Mage-D1 knockout (Mage-D1 KO)mice and littermate male wild-type (WT)mice.Micro-CT scanning was performed to observe mouse femoral bone mass,and ELISA and chemical assay were employed to detect serum levels of calcium,phosphorus,calcitonin,and parathyroid hormone in mice.After primary cultured BMSCs were identified with flow cytometry,immunofluorescence staining was utilized to detect the expression of Mage-D1 in BMSCs.BMSCs were infected by Mage-D1 silencing lentivirus,and then the cells were divided into negative control group (sh-NC)and silencing group (sh-Mage-D1).Cell scratch assay was conducted to detect the migration ability of BMSCs,and flow cytometry and CCK-8 assay were conducted to detect the cycle change and proliferation ability of BMSCs.After mineralization induction,alkaline phosphatase (ALP) staining and alizarin red staining were performed;RT-qPCR and Western blotting were used to measure the expression levels of ALP,Runx2 and Col1.RT-qPCR was used to detect mineralization-related genes p75NTR and Msx1.Results Compared with the WT mice,the femoral cortical bone thickness,cortical bone mineral content,cancellous bone mineral content,trabecular number,and cancellous bone surface density were decreased,and trabecular separation was increased in the Mage-D1 knockout homozygous mice (P<0.05).There were no significant changes in the serum levels of calcium,phosphorus,calcitonin and parathyroid hormone in mice after Mage-D1 knockout.Mage-D1 was expressed in the whole BMSCs and was highly expressed in the nucleus and perinuclear regions.Compared with the sh-NC BMSCs,the sh-Mage-D1 group had decreased proliferation ability (P<0.01),enhanced migration ability (P<0.01),and decreased expression of ALP,Runx2 and Col1 genes (P<0.05)and protein (P<0.01)after mineralization induction,milder ALP and alizarin red stain,and lower expression levels of p75NTR and Msx1.Conclusion Mage-D1 knockout can significantly reduce femur bone mass in mice.It can promote the proliferation and inhibit migration of BMSCs,and positively regulate their mineralization in vitro,and the p75NTR-Dlx1/Msx1 signaling axis may be involved in the regulation of bone metabolism by Mage-D1.

Objective To investigate the effects of amylin,also known as islet amyloid polypeptide(IAPP),on learning and memory abilities and the phosphatidylinositol 3-kinase/protein kinase B(PI3K/Akt)signaling pathway in APP/PS1 mice.Methods A total of 20 APP/PS1 mice were randomly divided into Alzheimer's disease(AD)group and IAPP group,with 10 mice in each group.The mice in the latter group were given an intraperitoneal injection of 0.5 μmol/L IAPP,and those of the former group received same dose of PBS.Both interventions were given once per day,for 10 weeks.Morris water maze test was used to measure the learning and memory abilities;HE staining was employed to observe the pathological changes in the hippocampus;Transmission electron microscopy was utilized to observe the ultrastructure of hippocampal neurons;Biochemical assay were conducted to detect the contents of glutathione peroxidase(GSH-Px),malondialdehyde(MDA)and superoxide dismutase(SOD)in hippocampal tissues;ELISA was applied to measure the levels of inflammatory factors such as IL-1β,IL-6,and TNF-α as well as content of Aβ42 in hippocampal tissues;And Western blotting was conducted to detect the expression of PI3K/Akt proteins.Results Compared with the AD group,significantly shorter platform latency(P＜0.01),increased number of traversing the platform and longer time to explore the hidden platform(P＜0.01)were observed in the IAPP group,but no such difference was seen in the swimming speed of the mice.HE staining displayed that the IAPP group had more and well-arranged nerve cells in the hippocampal tissue when compared with the AD group(P＜0.05).Lower Aβ protein expression(P＜0.01),reduced oxidative stress and decreased contents of inflammatory factors(P＜0.01)in hippocampal tissue were observed in the IAPP group than the AD group.The IAPP group showed clearer structure of neuronal mitochondria,reduced vacuolization,and better arranged microtubules and microfilaments,and elevated expression of p-PI3K/PI3K and p-Akt/Akt proteins when compared with the AD group(P＜0.01).Conclusion Amylin can reduce oxidative stress and inflammatory responses,improve learning and memory abilities in AD mice,and promote the activity of PI3K/Akt signaling pathway.

Objective To investigate the relationship between serum leucine-rich a-2 glycoprotein-1(LRG1),transforming growth factor-β1(TGF-β1)and the carotid intimal middle layer thickness(IMT)and short-term poor prognosis in acute cerebral infarction(ACI).Methods A total of 123 patients with ACI who were treated in Guangji Hospital of Suzhou from January 2020 to January 2023 were selected,and the patients were divided into normal group(23 cases),thickened group(30 cases)and plaque group(70 cases)according to the IMT,and 35 healthy physical examiners in Guangji Hospital of Suzhou during the same period were se-lected as the health control group,and the serum LRG1,TGF-β1 levels and IMT of 4 groups were compared.The patients were followed up for 3 months and divided into good prognosis group(75 cases)and poor prog-nosis group(48 cases)according to the prognosis.The correlation between serum LRG1,TGF-β1 and IMT was analyzed by Pearson method.Univariate and multivariate Logistic regression were used to analyze the risk factors of short-term poor prognosis in ACI patients.The receiver operating characteristics(ROC)curve was used to analyze the predictive value of serum LRG1 and TGF-β1 for the short-term poor prognosis of ACI.Re-sults The serum LRG1 level in health control group,normal group,thickened group and plaque group in-creased sequentially,and TGF-β1 level decreased sequentially(P＜0.05).Pearson correlation analysis showed that serum LRG1 was positively correlated with IMT,while TGF-β1 was negatively correlated with IMT(P＜0.05).Age,proportion of patients with diabetes,the National Institutes of Health Stroke Scale(NIHSS)score at admission,low-density lipoprotein cholesterol(LDL-C),fasting plasma glucose(FPG),white blood cell count(WBC),C-reactive protein(CRP)and serum LRG1 levels in the poor prognosis group were higher than those in the good prognosis group(P＜0.05),time from onset to thrombolysis was longer than that in the good prognosis group(P＜0.0.05),while the serum TGF-β1 level was lower than that in the good prognosis group(P＜0.05).Multivariate Logistic regression analysis showed that high NIHSS score,long time from onset to thrombolysis,elevated serum LRG1 level and decreased TGF-β1 level were risk factors for short-term poor prognosis in ACI patients(P＜0.05).ROC curve results showed that the area under the curve of the sin-gle and combined detection of serum LRG1 and TGF-β1 for predicting the short-term prognosis of ACI pa-tients were 0.824,0.708 and 0.902,respectively.Conclusion ACI patients have elevated serum LRG1 levels and decreased TGF-β1 levels.Serum LRG1 and TGF-β1 levels are closely related to the IMT and the short-term prognosis of ACI patients,and the combined detection of serum LRG1 and TGF-β1 levels have high ref-erence value for predicting the short-term poor prognosis of ACI patients.