The engineering application of microbially induced carbonate precipitation(MICP)is limited by pH-dependent conformational dynamics of urease.Focusing on the α-subunit urease from Sporosarcina pasteurii,this study integrated conductivity experiments and constant-pH molecular dynamics simulations to analyze active site conformational dynamics and catalytic function across pH 3-11.Results showed that under neutral conditions(pH 7-8),key histidine residues(HIS139/HIS249)exhibited minimal dis-placement(＜0.5 ?),the longest hydrogen bond lifetime(＞8 ps),highest conformational stability(root mean square deviation,RMSD:0.15-0.18 nm),and optimal catalytic activity(conductivity change rate:0.03 mS/cm·min-1,CaCO3 precipitation:3.84 g).Extreme pH(pH 3/11)induced structural collapse(displacement up to 1.8 ?)and complete activity loss.Simulations revealed that neutral pH sta-bilizes a protonation-dependent cooperative allosteric network by maintaining active site cavity volume(～120 ?3)and moderate conformational coherence(correlation coefficient～0.8).This work deciphers the molecular mechanism of pH-regulated urease dynamics through protonation states,providing theoreti-cal support for MICP applications in acidic mine tailing remediation and alkaline soil stabilization.

Icariin is a pure compound derived from Epimedium brevicornu Maxim, and it helps the regulation of male reproduction. Nevertheless, the role and underlying mechanisms of Icariin in mediating male germ cell development remain to be clarified. Here, we have demonstrated that Icariin promoted proliferation and DNA synthesis of mouse spermatogonial stem cells (SSCs). Furthermore, surface plasmon resonance iron (SPRi) and molecular docking (MOE) assays revealed that phosphodiesterase 5A (PDE5A) was an important target of Icariin in mouse SSCs. Mechanically, Icariin decreased the expression level of PDE5A. Interestingly, hydrogen peroxides (H 2 O 2 ) enhanced the expression level of phosphorylation H2A.X (p-H2A.X), whereas Icariin diminished the expression level of p-H2A.X and DNA damage caused by H 2 O 2 in mouse SSCs. Finally, our in vivo animal study indicated that Icariin protected male reproduction. Collectively, these results implicate that Icariin targets PDE5A to regulate mouse SSC viability and DNA damage and improves male reproductive capacity. This study thus sheds new insights into molecular mechanisms underlying the fate decisions of mammalian SSCs and offers a scientific basis for the clinical application of Icariin in male reproduction.
Male ; Animals ; Flavonoids/pharmacology* ; Mice ; Cyclic Nucleotide Phosphodiesterases, Type 5/drug effects* ; DNA Damage/drug effects* ; Cell Survival/drug effects* ; Cell Proliferation/drug effects* ; Spermatogonia/drug effects* ; Reproduction/drug effects* ; Adult Germline Stem Cells/metabolism* ; DNA Replication/drug effects*

OBJECTIVE: To screen factors affecting the prognosis of chronic myeloid leukemia (CML) patients, and construct a nomogram model for event-free survival (EFS). METHODS: To screen out meaningful variables by univariate and multivariate Cox regression analysis in CML patients, and construct a nomogram model using R software. The nomogram was validated using consistency index (C-index), receiver operating characteristic (ROC) curve, area under the ROC curve (AUC), calibration curve, decision curve analysis (DCA), and risk stratification analysis. RESULTS: This study analyzed data from 116 CML patients. Univariate and multivariate Cox regression analysis demonstrated that age, peripheral blood basophil percentage, BCR-ABL1 ^IS at 3 months, and red blood cell distribution width (RDW) were independent prognostic factors of EFS. Subsequently, a nomogram was constructed based on the above predictors. The C-index of the nomogram was 0.733(95%CI : 0.676-0.790). The AUC values for predicting 1-, 3-, and 5-year EFS rate were 0.765, 0.855, and 0.827, respectively. The results of the calibration curve and DCA curve showed that the predictive model had good consistency, as well as strong clinical utility. The patients were stratified into high-risk group and low-risk group based on the total score of the model, there was a significant difference in EFS between the two groups (P < 0.001). CONCLUSION Age, peripheral blood basophil percentage, BCR-ABL1 ^IS at 3 months, and RDW were associated with the prognosis of CML patients. The nomogram model constructed in this study can accurately predict the prognostic status of CML patients, but its widespread application still requires external and prospective validation.
Nomograms ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality* ; Proportional Hazards Models ; Erythrocyte Indices ; Risk Assessment/methods* ; Fusion Proteins, bcr-abl/genetics* ; Basophils ; Leukocyte Count ; Humans

Since the promulgation of the first Drug Administration Law of the People's Republic of China 40 years ago in 1984, China has undergone four main stages in the traditional Chinese medicine(TCM) regulation: the initial establishment of TCM regulation rules(1984-1997), the formation of a modern TCM regulatory system(1998-2014), the reform of the review and approval system for new TCM drugs(2015-2018), and the construction of a scientific regulation system for TCM(2019-2024). Over the past five years, a series of milestone achievements of TCM regulation in China have been achieved in the six aspects, including its strategic objectives and the establishment of a science-based regulatory system, the reform of the review and approval system for new TCM drugs, the optimization and improvement of the TCM standard system and its formation mechanism, comprehensive enhancement of regulatory capabilities for TCM safety, international harmonization of TCM regulation and its role in promoting innovation. Looking ahead, centered on advancing TCMRS to establish a sound regulatory framework tailored to the unique characteristics of TCM, TCM regulation will evolve into new reform patterns, advancing and extending across eight critical fronts, including the legal framework and policy architecture, the review and approval system for new TCM drugs, the quality standard and management system of TCM, the comprehensive quality & safety regulation and traceability system, the research and transformation system for TCMRS, AI-driven innovations in TCM regulation, the coordination between high-quality industrial development and high-level regulation, and the leadership in international cooperation and regulatory harmonization. In this way, a unique path for the development of modern TCM regulation with Chinese characteristics will be pioneered.
Humans ; China ; Drugs, Chinese Herbal/standards* ; History, 20th Century ; History, 21st Century ; Medicine, Chinese Traditional/trends*

The engineering application of microbially induced carbonate precipitation(MICP)is limited by pH-dependent conformational dynamics of urease.Focusing on the α-subunit urease from Sporosarcina pasteurii,this study integrated conductivity experiments and constant-pH molecular dynamics simulations to analyze active site conformational dynamics and catalytic function across pH 3-11.Results showed that under neutral conditions(pH 7-8),key histidine residues(HIS139/HIS249)exhibited minimal dis-placement(＜0.5 ?),the longest hydrogen bond lifetime(＞8 ps),highest conformational stability(root mean square deviation,RMSD:0.15-0.18 nm),and optimal catalytic activity(conductivity change rate:0.03 mS/cm·min-1,CaCO3 precipitation:3.84 g).Extreme pH(pH 3/11)induced structural collapse(displacement up to 1.8 ?)and complete activity loss.Simulations revealed that neutral pH sta-bilizes a protonation-dependent cooperative allosteric network by maintaining active site cavity volume(～120 ?3)and moderate conformational coherence(correlation coefficient～0.8).This work deciphers the molecular mechanism of pH-regulated urease dynamics through protonation states,providing theoreti-cal support for MICP applications in acidic mine tailing remediation and alkaline soil stabilization.

Amorphous solid dispersion (ASD) is one of the most effective formulation approaches to enhance the water solubility and oral bioavailability of poorly water-soluble drugs. However, maintenance of physical stability of amorphous drug is one of the main challenges in the development of ASD. Crystallization is a process of nucleation and crystal growth. The nucleation is the key factor that influences the physical stability of the ASD. However, a theoretical framework to describe the way to inhibit the nucleation of amorphous drug is not yet available. We reviewed the methods and theories of nucleation for amorphous drug. Meanwhile, we also summarized the research progress on the mechanism of additives influence on nucleation and environmental factors on nucleation. This review aims to enhance the better understanding mechanism of nucleation of amorphous drug and controlling over the crystal nucleation during the ASD formulation development.

Objective This study aimed to investigate the potential relationship between urinary metals copper (Cu), arsenic (As), strontium (Sr), barium (Ba), iron (Fe), lead (Pb) and manganese (Mn) and grip strength. Methods We used linear regression models, quantile g-computation and Bayesian kernel machine regression (BKMR) to assess the relationship between metals and grip strength.Results In the multimetal linear regression, Cu (β=-2.119), As (β=-1.318), Sr (β=-2.480), Ba (β=0.781), Fe (β= 1.130) and Mn (β=-0.404) were significantly correlated with grip strength (P < 0.05). The results of the quantile g-computation showed that the risk of occurrence of grip strength reduction was -1.007 (95％ confidence interval:-1.362, -0.652; P < 0.001) when each quartile of the mixture of the seven metals was increased. Bayesian kernel function regression model analysis showed that mixtures of the seven metals had a negative overall effect on grip strength, with Cu, As and Sr being negatively associated with grip strength levels. In the total population, potential interactions were observed between As and Mn and between Cu and Mn (Pinteractions of 0.003 and 0.018, respectively).Conclusion In summary, this study suggests that combined exposure to metal mixtures is negatively associated with grip strength. Cu, Sr and As were negatively correlated with grip strength levels, and there were potential interactions between As and Mn and between Cu and Mn.

Objective:To analyze the efficacy and safety of flumatinib,a second-generation tyrosine kinase inhibitor(TKI)independently developed in China,in patients with chronic myelogenous leukemia in chronic phase(CML-CP)who falied first-line and second-line treatment.Methods:The clinical data of 30 CML-CP patients treated with flumatinib in Lianyungang First People's Hospital from January 2020 to September 2022 were collected retrospectively.Among them,15 patients who received imatinib first-line treatment but failed treatment were included in the second-line group,and the other 15 patients who failed second-line treatment with nilotinib or dasatinib were included in the third-line group.The hematological and molecular responses of the patients in the two groups at 3,6 and 12 months of treatment,and the event-free survival(EFS)and adverse reactions of patients at the end of follow-up were statistical analyzed.Results:At 3,6,and 12 months of treatment,10,11,and 12 patients in the second line group achieved major molecular response(MMR),which was higher than that of 3,4,and 5 patients in the third line group(P=0.010,P=0.011,P=0.010).At 3 months of treatment,12 and 13 patients achieved complete hematological response(CHR)and early molecular response(EMR)in the second-line group,which was higher than that of 9 and 13 patients in the third-line group,but the difference between the two groups was not statistically significant(P=0.232,P=1.000);At 6 and 12 months of treatment,6 and 7 patients in the second-line group achieved MR4.5,which were higher than of 3 and 2 cases in the third-line group,but the difference was not statistically significant(P=0.427,P=0.713).The hematological adverse reactions of patients in the second-line group during treatment the period were mainly grade 1-2 thrombocytopenia and anemia,and no grade 3-4 of adverse reactions occurred.In the third-line group,there were 2 cases of grade 1-2 thrombocytopenia,grade 1-2 anemia and white blood cell 3 cases were reduced each,1 case of grade 3-4 anemia,2 cases of grade 3-4 neutropenia.The non-hematological adverse reactions in the second-line group were rash(2 cases),headache(1 case),diarrhea(1 case),fatigue(1 case),limb pain(1 case).There were 1 cases of diarrhea,1 cases of nausea,and 1 cases of edema in the third-line group.There was no statistical significance in hematological and non-hematological adverse reactions between the two groups of patients(P＞0.05).At the end of follow-up,the EFS rate of patients in the second-line group was higher than that in the third-line group(100％vs 93.3％),but the difference was not statistically significant(P=0.317).Conclusion:The second-generation TKI flumatinib independently developed in China,has good curative effect and safety for CML-CP patients who failed first-line and second-line treatment.

Objective:To investigate the clinical efficacy and safety of ixazomib-containing regimens in the treatment of patients with multiple myeloma(MM).Methods:A retrospective analysis was performed on the clinical efficacy and adverse reactions of 32 MM patients treated with a combined regimen containing ixazomib in the Hematology Department of the First People's Hospital of Lianyungang from January 2020 to February 2022.Among the 32 patients,15 patients were relapsed and refractory multiple myeloma(R/RMM)(R/RMM group),17 patients who responded to bortezomib induction therapy but converted to ixazomib-containing regimen due to adverse events(AE)or other reasons(conversion treatment group).The treatment included IPD regimen(ixazomib+pomalidomide+dexamethasone),IRD regimen(ixazomib+lenalidomide+dexamethasone),ICD regimen(ixazomib+cyclophosphamide+dexamethasone),ID regimen(ixazomib+dexamethasone).Results:Of 15 R/RMM patients,overall response rate(ORR)was 53.3％(8/15),among them,1 achieved complete response(CR),2 achieved very good partial response(VGPR)and 5 achieved partial response(PR).The ORR of the IPD,IRD,ICD and ID regimen group were 100％(3/3),42.9％(3/7),33.3％(1/3),50％(1/2),respectively,there was no statistically significant difference in ORR between four groups(x2=3.375,P=0.452).The ORR of patients was 50％after first-line therapy,42.9％after second line therapy,60％after third line therapy or more,with no statistically significant difference among them(x2=2.164,P=0.730).In conversion treatment group,ORR was 88.2％(15/17),among them,6 patients achieved CR,5 patients achieved VGPR and 4 patients achieved PR.There was no statistically significant difference in ORR between the IPD(100％,3/3),IRD(100％,6/6),ICD(100％,3/3)and ID(60％,3/5)regimen groups(x2=3.737,P=0.184).The median progression-free survival(PFS)time of R/RMM patients was 9 months(95％CI:6.6-11.4 months),the median overall survival(OS)time was 18 months(95％CI:11.8-24.4 months).The median PFS time of conversion treatment group was 15 months(95％CI:7.3-22.7 months),the median OS time not reached.A total of 10 patients suffered grade 3-4 adverse event(AE).The common hematological toxicities were leukocytopenia,anemia,thrombocytopenia.The common non-hematological toxicities were gastrointestinal symptoms(diarrhea,nausea and vomit),peripheral neuropathy,fatigue and infections.Grade 1-2 peripheral neurotoxicity occurred in 7 patients.Conclusion:The ixazomib-based chemotherapy regimens are safe and effective in R/RMM therapy,particularly for conversion patients who are effective for bortezomib therapy.The AE was manageable and safe.

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]