BACKGROUND:Hydroxyapatite is the main inorganic component of bone tissue.The polymer has the structure and function of a biomimetic extracellular matrix.The composites of hydroxyapatite and polymer have been widely studied. OBJECTIVE:To summarize the research status of hydroxyapatite composite polymer materials for bone tissue repair. METHODS:The articles collected in PubMed,Web of Science,CNKI and WanFang databases were searched from January 2010 to April 2023.The Chinese and English search terms were"hydroxyapatite,polymer,composites,degradability,bone defect,bone repair".Finally,75 articles were included for review. RESULTS AND CONCLUSION:Polymers often used in composite with hydroxyapatite for bone tissue repair include natural polymers(collagen,chitosan,alginate,serine protein,cellulose,hyaluronic acid,and polyhydroxybutyrate)and synthetic polymers[polylactic acid,polylactic acid-hydroxyacetic acid copolymer,poly(has-lactide),poly(amino acid)and poly(vinyl alcohol)].The mechanical properties and osteoinductivity of hydroxyapatite/polymer composites were improved compared with pure hydroxyapatite.Hydroxyapatite composite with polymers can be made into porous scaffolds,hydrogels,and coatings for bone repair.Hydroxyapatite/polymer composites can accelerate bone reconstruction with a slow release of loaded drugs and cytokines due to their bionic extracellular matrix structure and function.Based on the diversity of causes of bone defects and the fact that bone repair is a complex continuous process involving multiple biological factors and proteins,repair materials with mechanical properties matching bone tissue,degradation processes synchronized with bone repair,and efficient osteogenesis and vascularization need to be further investigated.

Objective To evaluate the bioequivalence and safety of two pyrazinamide tablets in healthy Chinese subjects.Methods An open,randomized,single-dose,two-sequence,two-cycle,double-cross trial design was used.All 48 healthy subjects(24 in fasting and 24 in fed trial)were randomized to receive a single oral dose of a 0.5 g pyrazinamide tablet(test or reference)per cycle.The plasma concentration of the drug was determined by liquid chromatography coupled to tandem mass spectrometry method.The pharmacokinetic parameters were calculated by WinNonlin v8.2,and the bioequivalence was evaluated by SAS 9.4.Results In the fasting group,the Cmax of the test and reference preparation of pyrazinamide tablets were(13.28±2.82)and(12.88±4.49)μg·mL-1,the AUC0-t were(139.17±26.58)and(138.63±28.92)h·μg·mL-1,the AUC0-∞ were(148.96±33.65)and(148.71±36.97)h·μg·mL-1 respectively.In the fed group,the Cmax of the test and reference preparation of pyrazinamide tablets were(11.89±1.96)and(11.99±1.92)μg·mL-1,the AUC0-t were(138.22±37.21)and(141.68±25.80)h·μg·mL-1,the AUC0-∞ were(152.20±32.41)and(151.04±28.05)h·μg·mL-,respectively.The 90％confidence intervals of Cmax,AUC0-t and AUC0-∞ geometric mean ratios of the test and reference preparation were all within 80.00％to 125.00％.The incidence of adverse events was 16.70％for both the test and reference preparation in the fasting group and 8.30％for both the test and reference preparation in the fed group,all of which were mild in severity.Conclusion The test and reference preparation of pyrazinamide tablets were bioequivalent,safe and well tolerated in healthy Chinese subjects under fasting and fed conditions.

Radioactive contamination can occur during nuclear accidents, loss of radioactive sources and the use of radiation for photography, disinfection and detection. When the human body is accidentally contaminated by radionuclides, radionuclides can cause harm to the human body through inhalation, ingestion, direct transdermal absorption and contaminated wounds into body tissues and organs. In the treatment of radionuclide contamination in vivo, the main way is decorporation therapy, which mainly uses specific decorporation agents to selectively bind radionuclides to form stable non-toxic complexes, thereby preventing their deposition in the body, accelerating excretion, and reducing the total accumulation of radionuclides in human tissues. At present, internal radionuclide decorporation agents promote the release of radionuclides from the body mainly by stopping the entry of radionuclides into the body, ion exchange, chelation, and binding of exportants to carriers. But recent studies have found that lysosomal exocytosis, the natural clearing function of activated cells, also has a significant exportation effect. In this paper, we first introduced and analyzed the mechanism and research status of radionuclide decorporation agents that have been used in clinical practice, such as the blocking effect of potassium iodide, the ion exchange effect of Prussian blue, the chelation effect of DTPA, and the urine alkalinization effect of sodium bicarbonate. The second part introduces the mechanism and research status of promising radionuclide decorporation agents. Among them, 3,4,3-LI (1,2-HOPO) and 5-LIO (Me-3,2-HOPO) are the most promising ones and have been approved for phase I clinical trials. Others such as catecholamines, polyethyleneimine and fullerenes are also being studied with great potential. Polyethyleneimine, as a biological macromolecular chelator, has more chelating sites and stronger targeting effects than small molecule chelators, and has achieved a real breakthrough in decorporation. Fullerenes are known as “free radical sponges” with good free radical scavenging ability and antioxidant properties. In recent years, biomaterials have been widely used in the field of radionuclide decorporation, which has greatly improved the decorporation efficiency. Chitosan and pectin have shown great advantages in promoting radionuclide decorporation, chitosan can adsorb metal ions through electrostatic interaction and chelation, and can also react with free radicals to remove free radicals generated after radionuclides enter the body. Pectin can promote uranium efflux, but the exact mechanism remains unclear. Liposomes and nanomaterials as carriers enhance the intracellular drug delivery, prolong the retention time of drugs in the body, reduce adverse reactions, and make the traditional efflux enhancers glow with new vitality and have good development prospects. The last part summarizes and looks forward to the future research direction of radionuclide decorporation agents. At present, the research on decorporation agents at home and abroad is mostly stuck in the stage of drug development and drug synthesis, and few have actually entered the clinical trial stage. Therefore, the optimization of existing decorporation agents and the development of new ligands are critical. The targeting, biological safety, oral availability, and treatment needs of large-scale contamination scenarios are still the focus of attention. In addition, from the point of view of the mechanism itself, it is a new idea to promote the emission of radionuclides by activating potential channels, which can be continuously explored.

Objective:To investigate the efficacy and safety of combining venetoclax (VEN) with hypomethylated drugs (HMA) in the treatment of higher-risk (IPSS-R score >3.5) myelodysplastic syndromes (MDS) .Methods:From March 2021 to December 2022, forty-five MDS patients with intermediate and high risk were treated with VEN in combination with HMAs. Clinical data were collected and analyzed retrospectively, including gender, age, MDS subtype, IPSS-R score, treatment regimen, and efficacy, etc. Kaplan-Meier method and Cox regression model were used to analyze univariate and multivariate of survival prognosis.Results:①Forty-five patients with MDS, including ninety-one percent were classified as high or very high risk. According to the 2023 consensus proposal for revised International Working Group response criteria for higher-risk MDS, the overall response rate (ORR) was 62.2% (28/45), with the complete response rate (CR) was 33.3% (15/45). For twenty-five na?ve MDS, the ORR was 68% (17/25) and the CR rate was 32% (8/25). In nonfirst-line patients, the ORR and CR were 55% (11/20) and 35% (7/20) respectively. The median cycle to best response was 1 (1-4). ②With a median followup of 189 days, the median overall survival (OS) time was 499 (95% confidence interval, 287-711) days, and most patients died from disease progression. Responders had a significantly better median OS time than nonresponders (499 days vs 228 days, P<0.001). Multifactor analysis revealed that IPSS-R score and response to treatment were independent prognostic factors for OS; the presence of SETBP1 gene mutations was associated with a longer hospital stay (51.5 days vs 27 days, P=0.017) . Conclusions:There is clinical benefit of venetoclax in combination with hypomethylated agents in patients with higher-risk MDS, but adverse events such as severe hypocytopenia during treatment should be avoided.

Objective:To analyze the clinical characteristics and prognosis of patients with myelodysplastic syndrome (MDS) with a bone marrow nucleated erythroid cell proportion of greater than or equal to 50% (MDS-E) .Methods:The clinical characteristics and prognostic factors of patients with MDS-E were retrospectively analyzed by collecting the case data of 1 436 newly treated patients with MDS diagnosed in the Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences from May 2014 to June 2023.Results:A total of 1 436 newly diagnosed patients with complete data were included in the study, of which 337 (23.5%) patients with MDS-E had a younger age of onset and lower neutrophil and platelet counts compared with those in patients with an erythroid cell proportion of less than 50% (MDS-NE) (all P<0.05). The proportion of MDS cases with ring sideroblasts (MDS-RS) was higher in the MDS-E group than in the MDS-NE group, and multi-hit TP53 mutations were more enriched in the MDS-E group than in the MDS-NE group (all P<0.05). Among patients with MDS-RS, the frequency of complex karyotypes and the TP53 mutation rate were significantly lower in the MDS-E group than in the MDS-NE group (0 vs 11.9%, P=0.048 and 2.4% vs 15.1%, P=0.053, respectively). Among patients with TP53 mutations, the frequencies of complex karyotypes and multi-hit TP53 mutations were significantly higher in the MDS-E group than in the MDS-NE group (87.5% vs 64.6%, P=0.003 and 84.0% vs 54.2%, P<0.001, respectively). Survival analysis of patients with MDS-RS found that the overall survival (OS) in the MDS-E group was better than that in the MDS-NE group [not reached vs 63 (95% CI 53.3-72.7) months, P=0.029]. Among patients with TP53 mutations and excess blasts, the OS in the MDS-E group was worse than that in the MDS-NE group [6 (95% CI 2.2-9.8) months vs 12 (95% CI 8.9-15.1) months, P=0.022]. Multivariate analysis showed that age of ≥65 years ( HR=2.47, 95% CI 1.43-4.26, P=0.001), mean corpuscular volume (MCV) of ≤100 fl ( HR=2.62, 95% CI 1.54-4.47, P<0.001), and TP53 mutation ( HR=2.31, 95% CI 1.29-4.12, P=0.005) were poor prognostic factors independent of the Revised International Prognostic Scoring System (IPSS-R) prognosis stratification in patients with MDS-E. Conclusion:Among patients with MDS-RS, MDS-E was strongly associated with a lower proportion of complex karyotypes and TP53 mutations, and the OS in the MDS-E group was longer than that in the MDS-NE group. Among patients with TP53 mutations, MDS-E was strongly associated with complex karyotypes and multi-hit TP53 mutations, and among TP53-mutated patients with excess blasts, the OS in the MDS-E group was shorter than that in the MDS-NE group. Age of ≥65 years, MCV of ≤100 fl, and TP53 mutation were independent adverse prognostic factors affecting OS in patients with MDS-E.

Objective To explore the application value of compressed sensing(CS)combined with deep learning(DL)reconstruction techniques for orbital MRI.Methods Thirty healthy individuals were selected to undergo MRI scanning with parallel imaging(S group with an acceleration factor of 2)and CS imaging(CS group with acceleration factors of 2,3,4 and 5),and images were acquired after DL reconstruction(DL group involving in S2DL,CS2DL,CS3DL,CS4DL and CS5DL sequences).All the groups were compared in terms of the subjective indexes including overall image quality,clarity of musculi oculi boundaries and diagnostic confidence level and the objective indexes including oculomotor-temporal muscle signal intensity ratio(SIR),oculomotor signal to noise ratio(SNR)and oculomotor-temporal muscle contrast to noise ratio(CNR).SPSS 26.0 statistical software was used for data analysis.Results S and CS groups after DL image reconstruction had the scores of the subjective indexes enhanced,and the differences of the subjective indexes between CS2 and S2,CS2DL and S2DL,CS2 and CS2DL were not statistically significant(P＞0.05);CS3 and CS2,CS5 and CS5DL did have significant differences in the overall image quality and clarity of musculi oculi boundaries(P＜0.05),while CS2DL and CS3DL did not(P＞0.05);there were significant differences in overall image quality,clarity of musculi oculi boundaries and diagnostic confidence level between CS3 and CS3DL and between CS4 and CS4DL.For the objective indexes,S and CS groups after image DL reconstruction had the scores of oculomotor SNR and oculomotor-temporal muscle CNR increased,and CS2,S2,CS2DL and S2DL had statistically significant differences in oculomotor SNR and oculomotor-temporal muscle CNR(P＜0.05);DL and CS groups were not significantly different in oculo-motor-temporal muscle SIR(P＞0.05).Conclusion DL reconstruction technique improves iamge quality while enhancing the image SNR and CNR.CS with an acceleration of 3 combined with DL reconstruction technique contibutes to shortening scanning time,strengthening image quality and bettering patient satisfaction,which is of great application value for orbital MRI.[Chinese Medical Equipment Journal,2024,45(10):60-65]

Purpose/Significance To construct a specialized database for inflammatory demyelinating disease of the central nervous system(CNS),so as to contribute to clinical research and improve the diagnostic and treatment capabilities of primary healthcare institu-tions.Method/Process Using the internet to collect medical data,after processing and analysis,the CNS inflammatory demyelinating disease database is constructed.Using statistical analysis,natural language processing(NLP),artificial intelligence(AI)image recog-nition and data visualization and other technologies,the database information is integrated and analyzed.Result/Conclusion A standard-ized big database for CNS inflammatory demyelinating diseases is constructed,which enables visualization of clinical research data,pro-vides patient education and specialist training,and facilitates multi-center teleconsultations.The establishment of a specialized database for the CNS inflammatory demyelinating disease can promote the transformation of medical research achievements,provide references for future real-world clinical research,optimize the process of diagnosis and treatment,and improve the clinical capability of primary healthcare institutions.

Objective To investigate the independent risk factors of comprehensive complication index(CCI)≥26.2 after radical resection of colon cancer,and use these factors to establish and verify a dynamic web-based nomogram model.Methods The clinical data of colon cancer patients who underwent radical resection in the Affiliated Hospital of Jiangnan University from November 2020 to April 2022 were retrospectively collected,and divided into main cohort(November 2020 to October 2021,n=438)and validation cohort(November 2021 to April 2022,n=196).CCI scores of all patients were obtained based on CCI calculator(http://www.assessurgery.com).Univariate and multivariate logistic regression analysis were performed to identify the risk factors for CCI≥26.2,and a nomogram model was constructed.Receiver operator characteristic curve(ROC),C index and calibration curve were used to evaluate the differentiation and consistency of predictive nomogram model,and the decision curve analysis was conducted to assess the clinical benefits of the model.Internal validation of the model is performed in the validation cohort.Results A total of 438 patients were identified in present study,of which 63 cases(14.4%)had CCI≥26.2.Multivariate logistic regression analysis revealed that age≥60 years(OR=2.662,95%CI 1.341-5.285,P=0.005),low third lumbar spine skeletal muscle mass index(L3MI;OR=4.572,95%CI 2.435-8.583,P<0.001),NRS2002≥3(OR=4.281,95%CI 2.304-7.952,P<0.001),and preoperative bowel obstruction(OR=3.785,95%CI 1.971-7.268,P<0.001)were significant independent risk factors for postoperative CCI≥26.2.Based on these results,a static and web-based dynamic nomogram was established(https://jndxfsyywcwksyf.shinyapps.io/DynNomCCI/).The C-index and area under the curve(AUC)of the nomogram were 0.742 and 0.787,respectively.The calibration curve indicated a good consistency between the predicted probability and the actual probability.In the validation cohort,the nomogram also presented good discrimination(C-index=0.722,AUC=0.795)and predictive consistency.The decision curve analysis indicated the clinical benefit and application value of the nomogram prediction model.Conclusion This easy-to-use dynamic nomogram based on 4 independent risk factors can conveniently and reliably predict the probability of CCI≥26.2 after radical resection of colon cancer,which helps optimize the preoperative evaluation system,formulate precise individualized treatment strategies,and enhance recovery after surgery.

Objective To investigate the correlation between the level of N-terminal pro-Brain natriuretic peptide(NT-proBNP)and cardiorespiratory fitness following acute exposure to high altitude.Methods Forty-six subjects were recruited from the Second Affiliated Hospital of Army Medical University in June 2022,including 19 males and 27 females.After completing cardiopulmonary exercise test(CPET),serological detection of myocardial cell-related markers,and multiple metabolites at a plain altitude(300 meters above sea level),all subjects flew to a high-altitude location(3900 meters above sea level).Biomarker testing and CPET were repeated on the second and third days after arrival at high altitude.Changes in serum biomarker and key CPET indicators before and after rapid ascent to high altitude were compared,and the correlation between serum levels of various myocardial cell-related markers and metabolites and high altitude cardiorespiratory fitness was analyzed.Results Compared with the plain altitude,there was a significant decrease in maximal oxygen uptake after rapid ascent to high altitude[(25.41±6.20)ml/(kg.min)vs.(30.17±5.01)ml/(kg.min),P<0.001].Serum levels of NT-proBNP,Epinephrine(E),plasma renin activity(PRA),angiotensin Ⅱ(Ang Ⅱ),angiotensin-converting enzyme 2(ACE2)and leptin(LEP)significantly increased,with all differences being statistically significant(P<0.05)after acute high altitude exposure.In contrast,no statistically significant differences were observed for creatine kinase MB(CK-MB),cardiac troponin I(cTnI),myoglobin(Myo)and norepinephrine(NE)(P>0.05).Correlation analysis showed a significant negative correlation between NT-proBNP at plain altitude(r=-0.768,P<0.001)and at high altitude(r=-0.791,P<0.001)with maximal oxygen uptake at high altitude.Multivariate linear regression analysis indicated that maximal oxygen uptake at plain altitude(t=2.069,P=0.045),NT-proBNP at plain altitude(t=-2.436,P=0.020)and at high altitude(t=-3.578,P=0.001)were independent influencing factors of cardiorespiratory fitness at high altitude.Conclusion Cardiorespiratory fitness significantly decreases after rapid ascent to high altitude,and the baseline NT-proBNP level at plain altitude is closely related to cardiorespiratory fitness at high altitude,making it a potential predictor indicator for high altitude cardiorespiratory fitness.

Objective To investigate disease characteristics and hospitalization costs of children with Mycoplasma Pneumoniae pneumonia(MPP)admitted to Shanghai municipal medical hospitals from 2019 to 2023.Methods Depending on the Shanghai Municipal Hospital Pediatric Alliance,we retrospectively investigated community acquired MPP pediatric patients hospitalized in 22 municipal hospitals with pediatric qualifications(including 4 children's hospitals)in Shanghai from Jan 2019 to Dec 2023.We collected the patients'diagnosis codes,gender,age,length of hospital stay,hospitalization costs,and whether they progressed to severe Mycoplasma pneumoniae pneumonia(SMPP).Results From 2019 to 2023,a total of 29 045 hospitalized children with MPP were treated,with 6 035 cases(20.8%)identified as SMPP in the 22 hospitals.Trend analysis revealed a rising trend with years in the proportion of SMPP patients(χ2trend=365.498,P<0.001).Among the 4 children's hospitals,there were 18 710 cases with MPP,including 4 078 cases(21.8%)of SMPP.The proportion of SMPP patients also showed an increasing trend with years(χ2trend=14.548,P<0.001),and the proportion in 2023(23.0%)was higher than that in previous years with statistical significance.There were statistical differences in the seasonal distribution of MPP cases between different years,with higher proportions in summer and autumn overall.The age distribution of hospitalized MPP children varied among different years,with school-age children accounting for the majority(56.8%)in 2023.There was no difference in the distribution of severe cases between different genders,but there were differences in the proportion of severe cases among different age groups in different years,with a gradual increase in severe cases among children aged 1 to 3 years(χ2trend=191.567,P<0.001).The average length of hospital stay for MPP during the epidemic was higher than that during non-epidemic periods,and there were statistically significant differences in the average length of hospital stay between different years(P<0.001).The individual hospitalization costs during the epidemic were higher than in other years,and there were statistically significant differences in individual hospitalization costs between different years(P<0.001).The total hospitalization costs were still higher in 2019 and 2023.The individual hospitalization costs for SMPP were higher than for non-SMPP cases.Conclusion MPP outbreaks occurred in Shanghai in 2019 and 2023,with the higher proportions in summer and autumn overall.Compared to previous years,the number of hospitalized MPP children in Shanghai was higher in 2023,with a higher proportion of SMPP cases,especially among children under 3 years old.The individual per capita hospitalization expenses for SMPP cases were higher than for non-SMPP cases.