BACKGROUND:The imbalance between bone resorption and bone formation in microgravity environments leads to significant bone loss in astronauts.Current research indicates that bone loss under microgravity conditions is the result of the combined effects of various cells,tissues,and systems. OBJECTIVE:To review different biological effects of microgravity on various cells,tissues,or systems,and summarize the mechanisms by which microgravity leads to the development of osteoporosis. METHODS:Databases such as PubMed,Web of Science,and the Cochrane Database were searched for relevant literature from 2000 to 2023.The inclusion criteria were all articles related to tissue engineering studies and basic research on osteoporosis caused by microgravity.Ultimately,85 articles were included for review. RESULTS AND CONCLUSION:(1)In microgravity environment,bone marrow mesenchymal stem cells tend to differentiate more into adipocytes rather than osteoblasts,and hematopoietic stem cells in this environment are more inclined to differentiate into osteoclasts,reducing differentiation into the erythroid lineage.At the same time,microgravity inhibits the proliferation and differentiation of osteoblasts,promotes apoptosis of osteoblasts,alters cell morphology,and reduces the mineralization capacity of osteoblasts.Microgravity significantly increases the number and activity of osteoclasts.Microgravity also hinders the differentiation of osteoblasts into osteocytes and promotes the apoptosis of osteocytes.(2)In a microgravity environment,the body experiences changes such as skeletal muscle atrophy,microvascular remodeling,bone microcirculation disorders,and endocrine disruption.These changes lead to mechanical unloading in the bone microenvironment,insufficient blood perfusion,and calcium cycle disorders,which significantly impact the development of osteoporosis.(3)At present,the mechanism by which microgravity causes osteoporosis is relatively complex.A deeper study of these physiological mechanisms is crucial to ensuring the health of astronauts during long-term space missions,and provides a theoretical basis for the prevention and treatment of osteoporosis.

Objective To compare the performance and efficacy of prognostic models constructed by different machine learning algorithms in predicting the survival period of lung transplantation (LTx) recipients. Methods Data from 483 recipients who underwent LTx were retrospectively collected. All recipients were divided into a training set and a validation set at a ratio of 7:3. The 24 collected variables were screened based on variable importance (VIMP). Prognostic models were constructed using random survival forest (RSF) and extreme gradient boosting tree (XGBoost). The performance of the models was evaluated using the integrated area under the curve (iAUC) and time-dependent area under the curve (tAUC). Results There were no significant statistical differences in the variables between the training set and the validation set. The top 15 variables ranked by VIMP were used for modeling and the length of stay in the intensive care unit (ICU) was determined as the most important factor. Compared with the XGBoost model, the RSF model demonstrated better performance in predicting the survival period of recipients (iAUC 0.773 vs. 0.723). The RSF model also showed better performance in predicting the 6-month survival period (tAUC _{6 months} 0.884 vs. 0.809, P = 0.009) and 1-year survival period (tAUC _{1 year} 0.896 vs. 0.825, P = 0.013) of recipients. Based on the prediction cut-off values of the two algorithms, LTx recipients were divided into high-risk and low-risk groups. The survival analysis results of both models showed that the survival rate of recipients in the high-risk group was significantly lower than that in the low-risk group (P<0.001). Conclusions Compared with XGBoost, the machine learning prognostic model developed based on the RSF algorithm may preferably predict the survival period of LTx recipients.

Objective To investigate the global burden of visceral leishmaniasis (VL) from 1990 to 2021 and predict the trends in the burden of VL from 2022 to 2035, so as to provide insights into global VL prevention and control. Methods The global age-standardized incidence, prevalence, mortality and disability-adjusted life years (DALYs) rates of VL and their 95% uncertainty intervals (UI) were captured from the Global Burden of Disease Study 2021 (GBD 2021) data resources. The trends in the global burden of VL were evaluated with average annual percent change (AAPC) and 95% confidence interval (CI) from 1990 to 2021, and gender-, age-, country-, geographical area- and socio-demographic index (SDI)-stratified burdens of VL were analyzed. The trends in the global burden of VL were projected with a Bayesian age-period-cohort (BAPC) model from 2022 to 2035, and the associations of age-standardized incidence, prevalence, mortality, and DALYs rates of VL with SDI levels were examined with a smoothing spline model. Results The global age-standardized incidence [AAPC = -0.25%, 95% CI: (-0.25%, -0.24%)], prevalence [AAPC = -0.06%, 95% CI: (-0.06%, -0.06%)], mortality [AAPC = -0.25%, 95% CI: (-0.25%, -0.24%)] and DALYs rates of VL [AAPC = -2.38%, 95% CI: (-2.44%, -2.33%)] all appeared a tendency towards a decline from 1990 to 2021, and the highest age-standardized incidence [2.55/10⁵, 95% UI: (1.49/10⁵, 4.07/10⁵)], prevalence [0.64/10⁵, 95% UI: (0.37/10⁵, 1.02/10⁵)], mortality [0.51/10⁵, 95% UI: (0, 1.80/10⁵)] and DALYs rates of VL [33.81/10⁵, 95% UI: (0.06/10⁵, 124.09/10⁵)] were seen in tropical Latin America in 2021. The global age-standardized incidence and prevalence of VL were both higher among men [0.57/10⁵, 95% UI: (0.45/10⁵, 0.72/10⁵); 0.14/10⁵, 95% UI: (0.11/10⁵, 0.18/10⁵)] than among women [0.27/10⁵, 95% UI: (0.21/10⁵, 0.33/10⁵); 0.06/10⁵, 95% UI: (0.05/10⁵, 0.08/10⁵)], and the highest mortality of VL was found among children under 5 years of age [0.24/10⁵, 95% UI: (0.08/10⁵, 0.66/10⁵)]. The age-standardized incidence (r = -0.483, P < 0.001), prevalence (r = -0.483, P < 0.001), mortality (r = -0.511, P < 0.001) and DALYs rates of VL (r = -0.514, P < 0.001) correlated negatively with SDI levels from 1990 to 2021. In addition, the global burden of VL was projected with the BAPC model to appear a tendency towards a decline from 2022 to 2035, and the age-standardized incidence, prevalence, mortality and DALYs rates were projected to be reduced to 0.11/10⁵, 0.03/10⁵, 0.02/10⁵ and 1.44/10⁵ in 2035, respectively. Conclusions Although the global burden of VL appeared an overall tendency towards a decline from 1990 to 2021, the burden of VL showed a tendency towards a rise in Central Asia and western sub-Saharan African areas. The age-standardized incidence and prevalence rates of VL were relatively higher among men, and the age-standardized mortality of VL was relatively higher among children under 5 years of age. The global burden of VL was projected to continue to decline from 2022 to 2035.

Objective: To study the efficacy of photosensitizer 8- methoxsalen (8-MOP) combined with ultraviolet radiation A (UVA) in inducing ferroptosis in mouse melanoma B16 cells, and to assess the resultant changes in immunogenicity, and their impact on subsequent immune activation after treatment. Methods: 1) Mouse melanoma B16 cells were cultured and treated with 8-MOP (100 ng/mL) and UVA (4 J/cm ), and then cultured in a constant temperature incubator (37℃, 5%CO ) for 24 hours after irradiation. 2) CCK8 (cell proliferation and toxicity) detection kit was used to detect the death rate of tumor cells. 3) LPO (lipid peroxide) and GSH (glutathione) detection kits were used to detect the degree of oxidative damage of tumor cells; Changes of Fe , mitochondrial membrane potential (JC-1) and BODIPY 581/591 C11 (lipid peroxidation detection kit) in tumor cells were detected by confocal microscope. Western blotting (WB) was performed to detect GPX4, SLC7A11 and NCOA4 to confirm ferroptosis. 4) The expression of HMGB1 (high mobility group protein 1), ATP and CRT (calreticulin) in the supernatant of tumor cell culture was detected by ELISA kit to evaluate the immunogenicity of tumor cells. 5) 1×10 B16 cells were injected subcutaneously into the skin of the back and neck of mice at a dose of 100 μL to construct a mouse melanoma model. Spleen mononuclear cells of tumor-bearing mice were extracted and immediately co-cultured with irradiated tumor cells for 48 h. Changes of dendritic cell (DC) maturity were detected by MHC-II, CD11c, CD80 and CD83 flow cytometry. Results: After UVAP, the survival rate of B16 cells decreased significantly (61.39±6.823 vs 84.81±7.026 vs 100.0±3.996, P<0.000 1, P<0.01). UVAP effectively induced ferroptosis in B16 cells, characterized by increased LPO and C11-bodipy lipid peroxidation, GSH depletion, Fe accumulation, mitochondrial membrane depolarization, decreased GPX4 and SLC7A11 protein expression, and increased NCOA4 expression, all in line with the trend of ferroptosis. UVAP also enhanced tumor cell immunogenicity, evidenced by elevated release of ATP, CRT, and HMGB1. The immunogenicity of B16 cells increased, the expressions of ATP, CRT and HMGB1 increased, and the DC maturity increased (CD80: 31.92±4.071 vs 19.77±3.177; CD83: 21.40±4.787 vs 12.19±1.487, P<0.001, P<0.01). Conclusion: The combined action of 8-MOP and UVA can induce ferroptosis in B16 tumor cells, enhance the immunogenicity of tumor cells, release more tumor antigens, promote the maturation of DC, present antigens better, thereby facilitating subsequent immune activation.

[摘 要] 目的：探究长链非编码RNA（lncRNA）小核仁RNA宿主基因14（SNHG14）靶向miR-579-3p/富含半胱氨酸的酸性分泌蛋白（SPARC）对肝细胞癌（HCC）细胞恶性生物学行为的影响。方法：常规培养人正常肝细胞（LO2）和HCC细胞Huh7、Hep3B、HepG2，将Huh7细胞随机分为对照组、sh-NC组、sh-SNHG14组、sh-SNHG14 + anti-NC组和sh-SNHG14 + anti-miR-579-3p组，qPCR法检测细胞中SNHG14、miR-579-3p和SPARC mRNA的表达水平，双萤光素酶报告基因实验验证SNHG14与miR-579-3p及miR-579-3p与SPARC调控关系，MTT法、划痕愈合实验、Transwell实验、流式细胞术，以及WB法分别检测各组Huh7细胞的增殖、迁移、侵袭能力、凋亡，以及Huh7细胞中PCNA、E-cadherin、vimentin、SPARC蛋白的表达。结果：在HCC细胞中SNHG14、SPARC mRNA呈高表达、miR-579-3p呈低表达（均P < 0.05）；SNHG14与miR-579-3p和miR-579-3p与SPARC mRNA间存在直接结合调控关系（均P < 0.05）。敲减SNHG14可明显抑制Huh7细胞的增殖、迁移、侵袭、PCNA、vimentin、SPARC mRNA及蛋白的表达（均P < 0.05），促进细胞凋亡、miR-579-3p和E-cadherin表达（均P < 0.05）；抑制miR-579-3p则可部分逆转敲减SNHG14对Huh7细胞的作用（均P < 0.05）。结论：敲减SNHG14可通过靶向miR-579-3p/SPARC轴抑制Huh7细胞的恶性生物学行为，促进其凋亡；SNHG14和miR-579-3p/SPARC轴可能是HCC治疗的潜在靶点。

ObjectiveTo explore the construction of a risk assessment indicator system for common infectious diseases in Shanghai’s childcare institutions, and to provide a reference standard for the prevention and control of infectious diseases, staff training and system construction in childcare institutions. MethodsBy combining the Delphi method with the literature review and expert consultation, the hierarchical dimensions and items at all levels of the risk assessment indicator system for common infectious diseases in Shanghai’s childcare institutions were constructed, and the weighting coefficients were determined by analytic hierarchy process. ResultsA total of 14 experts from the field of childcare institutions, infectious disease control, child healthcare and health supervision participated in the Delphi consultation. The system consisted of four core dimensions: organizational management, team building, hardware equipment, and infectious disease surveillance and disposal, with the weighting coefficients of 0.285 9, 0.261 6, 0.204 3 and 0.248 2, respectively. The evaluation indicator system consisted of 4 primary indicators, 15 secondary indicators and 45 tertiary items. The positivity coefficients of the two rounds of Delphi consultation were 0.93 and 1.00, the authority coefficients were both 0.81, and the Kendall’s coefficient of concordance were 0.44 and 0.49, respectively (P<0.01). ConclusionThe high expert engagement and coordination indicate that organizational management and team building remain the critical priorities for infectious disease prevention and control in Shanghai’s childcare institutions. It is recommended to strengthen financial investment, improve institutional mechanisms, and enhance personnel reserves and capacity building for healthcare teachers, thereby systematically upgrading the infectious disease control capabilities of childcare institutions.

Objective To analyze the influencing factors of survival of patients with airway stenosis requiring clinical interventions after lung transplantation. Methods Clinical data of 66 patients with airway stenosis requiring clinical interventions after lung transplantation were retrospectively analyzed. Univariate and multivariate Cox’s regression models were adopted to analyze the influencing factors of survival of all patients with airway stenosis and those with early airway stenosis. Kaplan-Meier method was used to calculate the overall survival and delineate the survival curve. Results For 66 patients with airway stenosis, the median airway stenosis-free time was 72 (52,102) d, 27% (18/66) for central airway stenosis and 73% (48/66) for distal airway stenosis. Postoperative mechanical ventilation time [hazard ratio (HR) 1.037, 95% confidence interval (CI) 1.005-1.070, P=0.024] and type of surgery (HR 0.400, 95%CI 0.177-0.903, P=0.027) were correlated with the survival of patients with airway stenosis after lung transplantation. The longer the postoperative mechanical ventilation time, the higher the risk of mortality of the recipients. The overall survival of airway stenosis recipients undergoing bilateral lung transplantation was better than that of their counterparts after single lung transplantation. Subgroup analysis showed that grade 3 primary graft dysfunction (PGD) (HR 4.577, 95%CI 1.439-14.555, P=0.010) and immunosuppressive drugs (HR 0.079, 95%CI 0.022-0.287, P<0.001) were associated with the survival of patients with early airway stenosis after lung transplantation. The overall survival of patients with early airway stenosis after lung transplantation without grade 3 PGD was better compared with that of those with grade 3 PGD. The overall survival of patients with early airway stenosis after lung transplantation treated with tacrolimus was superior to that of their counterparts treated with cyclosporine. Conclusions Long postoperative mechanical ventilation time, single lung transplantation, grade 3 PGD and use of cyclosporine may affect the survival of patients with airway stenosis after lung transplantation.

Aim To explore the impacts of high mobility group box 1 (HMGB1) on the phenotypes, endocy-tosis and extracellular signal-regulated kinase (ERK)/ Jun N-terminal protein kinase (JNK)/P38 mitogen-ac-tivated protein kinase (MAPK) signaling pathway in indoxyl sulfate (IS) -induced dendritic cells (DCs). Methods After treatment with 30, 300 and 600 (xmol · L

The analysis of ammonia nitrogen in real water samples is challenging due to matrix interferences and difficulties for rapid on-site analysis.On the basis of the standard method,i.e.water quality-determination of ammonia nitrogen-salicylic acid spectrophotometry(HJ 536-2009),a simple device for online detecting ammonia nitrogen was developed using a sequential injection analysis(SIA)system in this work.The ammonia nitrogen transformation system,color reaction system,and detection system were built in compatible with the SIA system,respectively.In particular,the detection system was assembled by employing light-emitting diode as the light source,photodiode as the detector,and polyvinylchloride tube as the cuvette,thus significantly reducing the volume,energy consumption and fabricating cost of the detection system.As a result,the accurate analysis of ammonia nitrogen in complex water samples was achieved.A quantitative detection of ammonia nitrogen in water sample was obtained in 12 min,along with linear range extending to 1000 μmol/L,precisions(Relative standard deviation,RSD)of 4.3%(C=10 μmol/L,n=7)and 4.2%(C=500 μmol/L,n=7),and limit of detection(LOD)of 0.65 μmol/L(S/N=3,n=7).The results of interfering experiments showed that the detection of ammonia nitrogen by the developed device was not interfered by the common coexisting ions and components,therefore the environmental water could be directly analyzed,such as reservoir water,domestic sewage,sea water and leachate of waste landfill.The analytical results were consistent with those obtained by the environmental protection standard method(Water quality determination of ammonia nitrogen-salicylic acid spectrophotometry,HJ 536-2009).In addition,the spiking recoveries were in the range of 92.3%-98.1%,further confirming the accuracy and practicality of the developed device.

Based on FangNet platform,the data of the prescriptions for the effective cases of post-stroke sequelae treated by national renowned Chinese medical practitioner LIU Mao-Cai were collected for the analysis of medication frequency of the prescribed drugs as well as their properties,flavors and meridian tropism.The medication rules of LIU Mao-Cai for treating post-stroke sequelae was summarized by analyzing the weight scale,co-occurrence and mutual exclusivity of the prescribed drugs and by drug-symptom association rule analysis and drug clustering analysis.The results showed that a total of 105 prescriptions involving 95 Chinese medicines were obtained.The drugs in the prescriptions were mainly warm in nature,sweet in flavor and had the meridian tropism of liver meridian.There were 17 driver herbs,and they were Astragali Radix,Gastrodiae Rhizoma,Corni Fructus,Codonopsis Radix,Eucommiae Cortex,Achyranthis Bidentatae Radix,Chuanxiong Rhizoma,Polygalae Radix,Curcumae Longae Rhizoma,Acori Tatarinowii Rhizoma,Ophiopogonis Radix,Atractylodis Macrocephalae Rhizoma,Salviae Miltiorrhizae Radix et Rhizoma,Poria,Uncariae Ramulus cum Uncis,Pinelliae Rhizoma Praeparatum,and Ligustri Lucidi Fructus.The results of drug co-occurrence analysis yielded 12 drug pairs such as Achyranthis Bidentatae Radix-Eucommiae Cortex,drug-symptom association rule analysis yielded 9 groups of drug-symptom association combinations such as Gastrodiae Rhizoma-dizziness,and cluster analysis yielded 4 drug combinations.The results indicated that the drugs for post-stroke sequelae treated by LIU Mao-Cai are mild in nature and mainly have the actions of supporting healthy-qi and replenishing the deficient,and Astragali Radix and Codonopsis Radix are often used to replenish the vital energy,and Corni Fructus,Achyranthis Bidentatae Radix and Eucommiae Cortex are usually used to tonify the liver and kidney.Moreover,simultaneous treatment of phlegm and blood stasis,and simultaneous application of purging and nourishing therapeutics are also stressed.