Reflections on the conduct of cell therapy clinical trials in medical institutes / 中华医学科研管理杂志

Objective:This paper introduces the concepts of " patient-centered cell therapy research management model", to provide reference for domestic medical institutions which conduct cell therapy clinical trials.Methods:We reviewed and summarized the experiences of conducting cell therapy at Peking University Shenzhen Hospital, including challenges and response plans regarding to the technology assessment, ethical evaluation risks and regulatory compliance. According to which, this paper aims to explore the reflections and practical experience of establishing a patient-centered, multi-stakeholder shared decision-making research management system.Results:The " patient-centered cell therapy research management model" ensures the reliability of research results through multi-stakeholder engagement in decision-making and management, adequate technical evaluation, effective ethical review and harmonized scientific research management, which not only meets the urgent health needs of the patient, but also promotes the standardized development of emerging technologies.Conclusions:The " patient-centered cell therapy research management model" is tailored for the cell therapy research, it is important to promote its further assessment and applications.

Correlation between body mass index and elbow vein grading in patients with metabolic syndrome based on superficial vein evaluation / 中国实用护理杂志

Objective:To analyze the correlation between body mass index (BMI) and the graded expression, subcutaneous depth, and diameter of elbow veins (cephalic vein, median vein, basilic vein) in patients with metabolic syndrome, to provide a method and theoretical basis for precise puncture of peripheral veins in obese patients.Methods:From January to October 2021, a total of 767 patients with metabolic syndrome with gastric volume reduction were selected as the study subjects by retrospective cohort study from the first Affiliated Hospital of Nanjing Medical University. According to the quartile Q1, M and Q3 of BMI level, they were divided into four groups: group A, group B, group C and group D. The subcutaneous depth and diameter of the cephalic vein, median vein and basilic vein were measured by B-ultrasound, and the three veins were evaluated and graded according to the grading criteria of superficial veins.The correlation between BMI and the subcutaneous depth and diameter of the three elbow veins was analyzed, and collected data such as puncture method and puncture times. Results:There was no significant correlation between BMI and subcutaneous depth and vessel diameter of the basilic vein ( r = 0.041 and 0.046, both P>0.05), the level of BMI was positively correlated with the subcutaneous depth and diameter of cephalic vein ( r = 0.275 and 0.117, both P<0.05) and median vein ( r = 0.236 and 0.148, both P<0.05), and a linear regression relationship was found ( OR values were 1.013-1.031, all P<0.05). 187 cases had direct puncture conditions under direct vision, and the success rate of one puncture was 86.63%(162/187).Venipuncture was completed under the guidance of B-mode ultrasound for 25 cases with failure under direct vision and 580 cases without direct puncture conditions under direct vision, the success rate of one puncture was 98.51% (596/605). Conclusions:With the increase of BMI level in patients with metabolic syndrome, the depth and diameter of both cephalic vein and median vein increase, venous exposure is difficult to express. The visual vein puncture guided by B-ultrasound is more accurate and catheterization is more reliable.

Clinical analysis of patients with oral and maxillofacial infections in oral emergency / 北京大学学报(医学版)

OBJECTIVE@#To analyze the composition, incidence and clinical characteristics of oral and maxillofacial infections in oral emergency.@*METHODS@#A retrospective study on patients with oral and maxillofacial infections who visited the Department of Oral Emergency in Peking University School and Hospital of Stomatology from January 2017 to December 2019 was conducted. General characteristics, such as disease composition, gender, age distribution and position of involved teeth were analyzed.@*RESULTS@#A total of 8 277 patients with oral and maxillofacial infections were finally collected, including 4 378 male patients (52.9%) and 3 899 female patients (47.1%), with gender ratio of 1.12:1. The common diseases were periodontal abscess (3 826 cases, 46.2%), alveolar abscess (3 537 cases, 42.7%), maxillofacial space infection (740 cases, 9.0%), sialadenitis (108 cases, 1.3%), furuncle & carbuncle (56 cases, 0.7%) and osteomyelitis (10 cases, 0.1%). Male patients were more easily affected by periodontal abscess, space infection and furuncle & carbuncle than female patients with the gender ratios 1.24:1, 1.26:1, 2.50:1 individually, while the incidence of alveolar abscess, sialadenitis, furuncle & carbuncle had no significant gender difference. Different diseases were prone to occur at different ages. The peak ages of alveolar abscess were 5-9 and 27-67 years, while the peak age of periodontal abscess was 30-64 years. Space infection tended to occur between 21-67 years. There were 7 363 patients with oral abscess (3 826 patients with periodontal abscess and 3 537 patients with alveolar abscess), accounting for 88.9% of all the patients with oral and maxillofacial infections, involving 7 999 teeth, including 717 deciduous teeth and 7 282 permanent teeth. Periodontal abscess usually occurred in permanent teeth, especially the molar teeth. Alveolar abscess may occur in both primary teeth and permanent teeth. In primary teeth, the most vulnerable sites were primary molar teeth and maxillary central incisors while in permanent teeth the most vulnerable sites were first molar teeth.@*CONCLUSION@#Understanding the incidence of oral and maxillofacial infection was conducive to the correct diagnosis and effective treatment of clinical diseases, as well as targeted education for patients of different ages and genders to prevent the occurrence of diseases.

Characteristics of allergen component in dust mite-induced allergic rhinitis patients / 临床耳鼻咽喉头颈外科杂志

Objective:To investigate the characteristics of allergen component in dust mite（DM） -induced allergic rhinitis（AR） patients, and provide reference for the diagnosis and treatment of AR. Methods:DM-induced AR patients with or without allergic asthma（AA） who visited the Allergy Department of Tongji Hospital, Huazhong University of Science and Technology between 2021 and 2022 were enrolled. Patients'age, gender, and visual analog scale（VAS） for symptoms were recorded. sIgE and sIgG4 levels of allergen components such as Der f1, Der f2, Der p1, Der p2, Der p7, Der p10, Der p21, and Der p23 were detected using a protein chip method. The sensitization characteristics of the allergen components in the patients were observed, and the correlation between sIgE, sIgG of each component and VAS as well as the component differences between AR and AR with AA（AR&AA） were evaluated. Results:A total of 87 DM-induced AR patients were enrolled, with 42.5% of them were AR&AA, their VAS scores were significantly higher than those of AR patients（6.38±1.95 vs 5.25±1.85, P=0.009 8）. The order of sensitization rates for DM components was as follows: Der p2（82.8%）, Der f2（81.6%）, Der p1（74.7%）, Der f1（70.1%）, and Der p23（35.6%）. The order of positive rates for sIgG4 was: Der p2（21.8%）, Der f2（13.8%）, Der p21（8.0%）, and Der p7（6.9%）. There were no correlation between the sIgE, sIgG4 levels or positive numbers of components and VAS scores, but there were positive correlations between sIgE, sIgG4 concentrations of components. Compared with AR patients, AR&AA patients had higher levels of sIgE for Der p（60.5[7.2-91.1]vs 14.0[4.8-45.1], P=0.02）, Der f（49.8[15.7-81.6]vs 21.3[7.0-50.2], P=0.04）, Der p1（27.2[0.7-51.5]vs 2.6[0.2-24.9], P=0.02）, Der p2（20.0[1.4-60.6]vs 5.5[0.6-19.1], P=0.004）, and Der f2（58.9[16.0-89.2]vs 23.4[0.9-56.8], P=0.009）, and a higher proportion of AR with AA patients had sIgE levels of Der p1（70.3% vs 48.0%, P=0.038） and Der p23（27.0% vs 14.0%, P=0.039） that were ≥3 grades. Conclusion:Der p1/f1, Der p2/f3, and Der p23 are the major components of DM sensitized AR patients. Multiple component sensitization and sIgE, sIgG4 levels of each component are not correlated with the severity of AR. The sIgE levels of the Der p1/f1, Der p2/f3, and Der p23 components in AR&AA patients are higher than AR.

Rapid 3D roll-up of gas-phase planar gold clusters and affinity and alienation for Mg and Ge: A theoretical study of MgGeAun (n=1-12) clusters.

A cluster is a special matter level above a single atom and between macroscopic and microscopic matter, and it is an important bridge to understanding the relationship between the structure and function of matter. Here, we perform a comprehensive theoretical study of 2D planar Aun (n = 1-12) clusters doped with both magnesium and germanium. Two interesting results are found, namely the rapid 3D "roll-up" structural growth of the GeMgAun (n = 1-12) cluster ground state isomers, and the relative "alienation" of the different sizes of the Aun (n = 1-12) cluster framework towards the Ge atom, and the relative "affinity" towards the Mg atom. This study will not only enrich the data on gold-based clusters but will also provide a simple and clear theoretical guide for the 3D structuring of planar clusters, i.e. the doping of different classes of "affinition" and "alienatation" atoms.

Systematic research on gallium atom-doped neutral small- and medium-sized gas-phase magnesium clusters: A DFT study of GaMgn (n=2-12) clusters.

Structure, stability, charge transfer, chemical bonding, and spectroscopic properties of Ga atom-doped neutral Mgn (n = 2-12) clusters have been systematically investigated by CALYPSO and density functional theory. All cluster structures are based on "tetrahedral" and "yurt-like" growth except for GaMg2. The ground state isomer of GaMg8 with high symmetry structure is predicted to be the best-fit candidate for the "magic" cluster because of its excellent stability. Natural bond orbital calculations reveal that Ga and Mg atoms play the role of electron acceptor and donor in all ground state isomers, while the orbitals in both Ga and Mg are sp-hybridized. Most importantly, chemical bonding studies based on atom-in-molecular theory have shown that the lowest-energy state of GaMg4 is so special, in that it has not only the critical size for the appearance of Mg-Mg covalent bonds, but also the only cluster that has both Ga-Mg covalent and non-covalent bonds. Finally, theoretical calculations of IR and Raman spectra of all ground state isomers indicate that the spectra of these clusters are observable in the low-frequency band, and thus they can be identified by spectroscopic experiments. Furthermore, the bond heterogeneity of the Ga-Mg in the GaMg4 ground state isomer has also been specifically investigated, including the fixed GaMg4 structure with Mg atoms added in different directions, as well as ab initio molecular dynamics sampling at different temperatures.

Structural Genomic Analysis of SARS-CoV-2 and Other Coronaviruses.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the causative agent of the coronavirus disease 2019 (COVID-19) pandemic. In this study, we conducted a comparative analysis of the structural genes of SARS-CoV-2 and other CoVs. We found that the sequence of the E gene was the most evolutionarily conserved across 200 SARS-CoV-2 isolates. The E gene and M gene sequences of SARS-CoV-2 and NC014470 CoV were closely related and fell within the same branch of a phylogenetic tree. The absolute diversity of E gene and M gene sequences of SARS-CoV-2 isolates was similar to that of common CoVs (C-CoVs) infecting other organisms. The absolute diversity of the M gene sequence of the KJ481931 CoV that can infect humans was similar to that of SARS-CoV-2 and C-CoVs infecting other organisms. The M gene sequence of KJ481931 CoV (infecting humans), SARS-CoV-2 and NC014470 CoV (infecting other organisms) were closely related, falling within the same branch of a phylogenetic tree. Patterns of variation and evolutionary characteristics of the N gene and S gene were very similar. These data may be of value for understanding the origins and intermediate hosts of SARS-CoV-2.

Computational Exploration on the Structural and Optical Properties of Gold-Doped Alkaline-Earth Magnesium AuMgn (n = 2-12) Nanoclusters: DFT Study.

Using CALYPSO crystal search software, the structural growth mechanism, relative stability, charge transfer, chemical bonding and optical properties of AuMgn (n = 2-12) nanoclusters were extensively investigated based on DFT. The shape development uncovers two interesting properties of AuMgn nanoclusters contrasted with other doped Mg-based clusters, in particular, the planar design of AuMg3 and the highly symmetrical cage-like of AuMg9. The relative stability study shows that AuMg10 has the robust local stability, followed by AuMg9. In all nanoclusters, the charge is transferred from the Mg atoms to the Au atoms. Chemical bonding properties were confirmed by ELF analysis that Mg-Mg formed covalent bonds in nanoclusters larger than AuMg3. Static polarizability and hyperpolarizability calculations strongly suggest that AuMg9 nanocluster possesses interesting nonlinear optical properties. Boltzmann distribution weighted average IR and Raman spectroscopy studies at room temperature verify that these nanoclusters are identifiable by spectroscopic experiments. Finally, the average bond distance and average nearest neighbor distance were fully investigated.

A Study of Urodynamic Parameters at Different Bladder Filling Stages for Predicting Upper Urinary Tract Dilatation / 대한배뇨장애요실금학회지

Purpose@#To identify more accurate predictors of upper urinary tract dilatation (UUTD) in neurogenic bladder (NB) children, we studied the relationship among urodynamic parameters at different bladder filling stages, detrusor leak point pressure (DLPP) and UUTD. @*Methods@#A total of 158 children (3–16 years) with NB were included and then divided into 2 groups according to whether their NB diagnosis was complicated with UUTD: the UUTD group (39 patients) and those without UUTD group (control group, 119 patients). The bladder filling phase was divided into 3 equal parts: the early, middle, and end filling stages. The bladder compliance (BC) and detrusor pressure (△Pdet) at each phase and DLPP at the end filling stage were recorded. @*Results@#A BC8 cm H2O in the early stage, 20 cm H2O in the middle stage and 25 cm H2O in the end stage are more sensitive than △Pdet >40 cm H2O in the end stage (82%, 85%, 85%, vs. 49%). A DLPP cutoff value of 20 cm H2O showed higher sensitivity for predicting UUTD than 40 cm H2O. @*Conclusions@#Low BC and a high △Pdet in the middle and end filling stages are more accurate factors than classic indicators for predicting UUTD. In addition, a DLPP value of >20 cm H2O in the end bladder filling stage shows high sensitivity.

Regulation of Gut Microbiota Disrupts the Glucocorticoid Receptor Pathway and Inflammation-related Pathways in the Mouse Hippocampus

An increasing number of studies have recently indicated the important effects of gut microbes on various functions of the central nervous system.However, the underlying mechanisms by which gut microbiota regulate brain functions and behavioral phenotypes remain largely unknown. We therefore used isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomic analysis to obtain proteomic profiles of the hippocampus in germ-free (GF), colonized GF, and specific pathogen-free (SPF) mice. We then integrated the resulting proteomic data with previously reported mRNA microarray data, to further explore the effects of gut microbes on host brain functions. We identified that 61 proteins were upregulated and 242 proteins were downregulated in GF mice compared with SPF mice. Of these, 124 proteins were significantly restored following gut microbiota colonization. Bioinformatic analysis of these significant proteins indicated that the glucocorticoid receptor signaling pathway and inflammation-related pathways were the most enriched disrupted pathways. This study provides new insights into the pathological mechanisms of gut microbiota-regulated diseases.

Clinical analysis of children and adolescents emergency dental trauma cases / 北京大学学报(医学版)

OBJECTIVE@#To analyze the etiological and clinical characteristics of oral emergency patients under 18 years with dental trauma, and to provide guidance on the prevention and treatment in children and adolescents.@*METHODS@#A retrospective study on the intact data of the dental trauma patients under 18 years from January 2016 to December 2018 in the Department of Oral Emergency in Peking University School of Stomatology was conducted, and the distribution of the patients' gender, age and visiting time, as well as the number and position of traumatic teeth, diagnostic classification, and multiple injury with dental trauma were analyzed.@*RESULTS@#During the period, 54.2% of the first visit dental trauma patients (10 164) were children or adolescents (5 506). The two peak ages were 3-4 and 7-9 years. The incidence of the male was higher than the female in every age group (Wilcoxon test, P < 0.001). From May to June and September to November, there were more cases of dental trauma. The peak time of daily dental trauma cases was from 19:00 to 20:00 (Jonckheere-Terpstra test, P < 0.001). The positions of traumatic teeth in both sides were approximate symmetrical, and maxillary central incisors were the most affected. 52.3% of the patients suffered multiple teeth injuries. Among the permanent teeth trauma, enamel and dentin fracture was the most common (24.7%), followed by concussion (20.5%), sub-luxation (17.9%) and complicated crown fracture (14.4%). And among the primary teeth trauma, subluxation was the most common (31.1%), followed by concussion (14.5%) and lateral luxation (9.5%). 19.7% of the children and adolescent dental trauma patients were also suffered maxillofacial soft or hard tissue injury.@*CONCLUSION@#The incidence of dental trauma in children and adolescents is higher than that in adults. There were two age peaks among the children and adolescents patients. Primary teeth and young permanent teeth were usually suffered. Clinical treatment should be considered along with the characteristics of child tooth growth. In order to prevent the occurrence of dental trauma, early orthodontic intervention should be carried out in children with severe overjet. Families, schools and nursery institutions should strengthen the protection against dental trauma.

Antibody-dependent enhancement (ADE) of SARS-CoV-2 infection in recovered COVID-19 patients: studies based on cellular and structural biology analysis

Antibody-dependent enhancement (ADE) has been reported in several virus infections including dengue fever virus, severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) coronavirus infection. To study whether ADE is involved in COVID-19 infections, in vitro pseudotyped SARS-CoV-2 entry into Raji cells, K562 cells, and primary B cells mediated by plasma from recovered COVID-19 patients were employed as models. The enhancement of SARS-CoV-2 entry into cells was more commonly detected in plasma from severely-affected elderly patients with high titers of SARS-CoV-2 spike protein-specific antibodies. Cellular entry was mediated via the engagement of Fc{gamma}RII receptor through virus-cell membrane fusion, but not by endocytosis. Peptide array scanning analyses showed that antibodies which promote SARS-CoV-2 infection targeted the variable regions of the RBD domain. To further characterize the association between the spike-specific antibody and ADE, an RBD-specific monoclonal antibody (7F3) was isolated from a recovered patient, which potently inhibited SARS-Cov-2 infection of ACE-2 expressing cells and also mediated ADE in Raji cells. Site-directed mutagenesis the spike RBD domain reduced the neutralization activity of 7F3, but did not abolish its binding to the RBD domain. Structural analysis using cryo-electron microscopy (Cryo-EM) revealed that 7F3 binds to spike proteins at a shift-angled pattern with one "up" and two "down" RBDs, resulting in partial overlapping with the receptor binding motif (RBM), while a neutralizing monoclonal antibody that lacked ADE activity binds to spike proteins with three "up" RBDs, resulting in complete overlapping with RBM. Our results revealed that ADE mediated by SARS-CoV-2 spike-specific antibodies could result from binding to the receptor in slightly different pattern from antibodies mediating neutralizations. Studies on ADE using antibodies from recovered patients via cell biology and structural biology technology could be of use for developing novel therapeutic and preventive measures for control of COVID-19 infection.

Searching new structures of beryllium-doped in small-sized magnesium clusters: Be2 Mgn Q (Q = 0, -1; n = 1-11) clusters DFT study.

Using CALYPSO method to search new structures of neutral and anionic beryllium-doped magnesium clusters followed by density functional theory (DFT) calculations, an extensive study of the structures, electronic and spectral properties of Be2 Mgn Q (Q = 0, -1; n = 2-11) clusters is performed. Based on the structural optimization, it is found that the Be2 Mgn Q (Q = 0, -1) clusters are shown by tetrahedral-based geometries at n = 2-6 and tower-like-based geometries at n = 7-11. The calculations of stability indicate that Be2 Mg5 Q=0 , Be2 Mg5 Q=-1 , and Be2 Mg8 Q=-1 clusters are "magic" clusters with high stability. The NCP shows that the charges are transferred from Mg atoms to Be atoms. The s- and p-orbitals interactions of Mg and Be atoms are main responsible for their NEC. In particular, chemical bond analysis including molecular orbitals (MOs) and chemical bonding composition for magic clusters to further study their stability. The results confirmed that the high stability of these clusters is due to the interactions between the Be atom and the Mg5 or Mg8 host. Finally, theoretical calculations of infrared and Raman spectra of the ground state of Be2 Mgn Q (Q = 0, -1; n = 1-11) clusters were performed, which will be absolutely useful for future experiments to identify these clusters.

UK medical research administration model and enlightenment-Adding value in research / 中华医学科研管理杂志

Objective:This paper introduces the concepts of "Adding Value in Research" , along with strategies adopted by National Institute of Health Research(NIHR)in practice, to enlighten the establishment of domestic medical research administration and support system.Methods:Analyze the idea and its applications of Adding Value in Research in the UK medical research supervision and support system combined with concept discussion.Results:The key issues should be focused by the establishment of medical research supervision and support system including setting the priorities by evidence-based decision making, providing research design platform, whole process management, accessible and usable platform, and disseminating the findings effectively.Conclusions:All the stakeholders such as regulatory bodies, research institutions, funding agencies and researchers should pay attention to "Adding Value in Research" and engage in the establishment of related mechanisms.

Antimicrobial resistance of gram-negative bacilli isolated from 13 teaching hospital across China in 2018 / 中华检验医学杂志

Objective:To monitor the susceptibility of common used antimicrobial agents against nosocomial Gram-negative bacilli in 2018 across China.Methods:Prospective collection of Gram-negative bacilli from 13 teaching hospitals nationwide from January to December 2018. The minimal inhibitory concentration (MICs) of antibiotics such as meropenem was determined by agar dilution methods and broth microdilution methods. Interpretation of results using the Clinical and Laboratory Standards Institute(CLSI) 2019 M100S (29th Edition) standard. Data were analyzed by using WHONET-5.6 software.Results:A total of 1 214 non-repetitive Gram-negative bacilli were collected, accounting for 96.7% (1 174/1 214) of blood and sterile body fluid samples. The activity of antimicrobial agents against 871 strains of Enterobacteriaceae was as follows in descending order of susceptible rate: amikacin (93.2%, 812/871), meropenem (92.0%, 801/871), ertapenem (88.9%, 774/871), imipenem (88.4%, 770/871), piperacillin-tazobactam (84.0%, 732/871), cefoperazone-sulbactam (83.1%, 724/871), cefepime (71.4%, 622/871), minocyline (68.9%, 600/871), ceftazidime (66.9%, 583/871), levofloxacin (54.4%, 474/871).The resistance rates of Escherichia coli to the third generation cephalosporins were 61.5% (155/252) (ceftriaxone) and 60.7% (153/252) (cefotaxime), respectively. The resistance rates of Klebsiella pneumoniae to the third generation cephalosporins were 56.6% (126/222) (ceftriaxone) and 57.9% (129/222) (cefotaxime), respectively. The incidence of extended-spectrum β lactamase (ESBLs) positive E. coli and K. pneumoniae was 50.2% (127/252) and 18.2% (40/222), respectively. Over 95% of all the ESBLs positive strains were susceptible to imipenem and meropenem. The incidence of carbapenem-resistant Escherichia coli and Klebsiella pneumoniae was 2.8% (7/252) and 20.4% (45/222), respectively. For Enterobacter cloacae, Klebsiella aerogenes, Citrobacter freundii, the most susceptible agent were tigecycline (96.3%-100%), followed by amikacin (94.9%-97.1%), meropenem (89.8%-96.6%)and imipenem (89.8%-94.9%).The susceptibility of Proteus mirabilis, Morganella morganii and Serratia marcescens to meropenem and amikacin was over 90%.A total of 67 strains of carbapenems resistant enterobacteriaceae(CRE) were detected. Modified carbapenem inactivation method showed, 45 strains were serine carbapenemase and 20 were metalloenzymes. The susceptibility of Pseudomonas aeruginosa to meropenem and imipenem were 73.2% (112/153) and 66.0% (101/153), respectively. Acinobacter baumannii has the highest sensitivity to colistin (100%, 163/163), followed by tigecycline (87.1%, 142/163).Compared with other sources of infection, specimens of bloodstream infections were less resistant to Klebsiella pneumoniae (17.6%, 27/153 vs 21.7%, 15/69) and Acinetobacter baumannii (68.3%, 71/104 vs 71.2%, 42/59). Escherichia coli (2.5%,4/198 vs 0%,0/54) and Pseudomonas aeruginosa (37%, 33/89 vs 18.8%, 12/64) have a high proportion of carbapenem resistance. Conclusions:Carbapenems still maintain high antibacterial activity against Enterobacteriaceae bacteria, especially strains producing only ESBLs. Carbapenem-resistant Klebsiella pneumoniae should be given sufficient attention. Carbapenemase is the most important drug resistance mechanism of carbapenem-resistant Enterobacteriaceae in China.

Effects of salinomycin on proliferation and apoptosis of oral squamous cell carcinoma / 北京大学学报(医学版)

OBJECTIVE@#To investigate the effects of salinomycin on the proliferation and apoptosis of oral squamous carcinoma cells and to further understand the mechanisms of these effects.@*METHODS@#The human oral squamous carcinoma cell line CAL-27 was cultured in different concentrations of salinomycin and cisplatin. After co-culture with 0, 1, 2, 4, 8, 16 and 32 μmol/L salinomycin or 0, 1.25, 2.5, 5, 10, 20, 40 and 80 μmol/L cisplatin for 24 hours and 48 hours, the proliferation of oral squamous carcinoma cells were detected by cell counting kit-8(CCK-8) assay. After being exposed to 0, 2, 4, 8 μmol/L salinomycin and 0, 5, 10, 20 μmol/L cisplatin for 48 hours, the cell cycle of oral squamous carcinoma cells was detected by flow cytometry assay, and Western blot analysis was performed to analyze the expressions of cysteine-containing aspartate-specific proteases-3(Caspase-3), cysteine-containing aspartate-specific proteases-9(Caspase-9), poly ADP-ribose polymerase (PARP), protein kinase B (Akt) and phosphorylated protein kinase B (p-Akt) protein in oral squamous carcinoma cells.@*RESULTS@#Both salinomycin and cisplatin significantly inhibited the proliferation of oral squamous cell carcinoma CAL-27 cells in a time- and dose-dependent manner. However, compared with the first-line chemotherapeutic drug cisplatin, salinomycin showed stronger anti-proliferation activity in oral squamous carcinoma cells than cisp-latin (P < 0.001). After being exposed to 8 μmol/L salinomycin, CAL-27 cells exhibited markedly higher proportion in quiescent/ first gap phases (40.40%±1.99% vs. 64.46%±0.90%, P < 0.05), and had a significantly lower proportion in synthesis phases and second gap / mitosis phases (24.32%±2.30% vs. 18.73%±0.61%, P < 0.05; 35.01%±1.24% vs. 16.54%±1.31%, P < 0.05) compared with the dimethyl sulfoxide control group; moreover cisplatin didn't show cell-cycle specific effect on CAL-27. Western blot proved that salinomycin could up-regulate the expressions of Caspase-3 and Caspase-9 protein in oral squamous cell carcinoma CAL-27 cells (P < 0.05). At the same time, the levels of PARP, Akt and p-Akt protein were down-regulated (P < 0.05).@*CONCLUSION@#Compared with cisplatin, salinomycin has a better inhibitory effect on the proliferation of oral squamous carcinoma cells and blocks the cell cycle process at the quiescent / first gap phase. At the same time, salinomycin could trigger apoptosis of oral squamous carcinoma cells and the mechanism is associated with the Akt/p-Akt signaling pathway.

Systematic Theoretical Study on Structural, Stability, Electronic, and Spectral Properties of Si2 Mg n Q (Q = 0, ±1; n = 1-11) Clusters of Silicon-Magnesium Sensor Material.

By using CALYPSO searching method and Density Functional Theory (DFT) method at the B3LYP/6-311G (d) level of cluster method, a systematic study of the structures, stabilities, electronic and spectral properties of Si2 Mg n Q (n = 1-11; Q = 0, ±1) clusters of silicon-magnesium sensor material, is performed. According to the calculations, it was found that when n > 4, most stable isomers in Si2 Mg n Q (n = 1-11; Q = 0, ±1) clusters of silicon-magnesium sensor material are three-dimensional structures. Interestingly, although large size Si2 Mg n Q clusters show cage-like structures, silicon atoms are not in the center of the cage, but tend to the edge. The Si2 Mg 1 , 5 , 6 , 8 - 1 and Si2 Mg 13 , 4 , 7 , 9 , 10 + 1 clusters obviously differ to their corresponding neutral structures, which are in good agreement with the calculated values of VIP, AIP, VEA, and AEA. |VIP-VEA| values reveal that the hardness of Si2Mgn clusters decreases with the increase of magnesium atoms. The relative stabilities of neutral and charged Si2 Mg n Q (n = 1-11; Q = 0, ±1) clusters of silicon-magnesium sensor material is analyzed by calculating the average binding energy, fragmentation energy, second-order energy difference and HOMO-LUMO gaps. The results reveal that the Si2 Mg 3 0 , Si2 Mg 3 - 1 , and Si2 Mg 3 + 1 clusters have stronger stabilities than others. NCP and NEC analysis results show that the charges in Si2 Mg n Q (n = 1-11; Q = 0, ±1) clusters of silicon-magnesium sensor material transfer from Mg atoms to Si atoms except for Si2 Mg 1 + 1 , and strong sp hybridizations are presented in Si atoms of Si2 Mg n Q clusters. Finally, the infrared (IR) and Raman spectra of all ground state of Si2 Mg n Q (n = 1-11; Q = 0, ±1) clusters of silicon magnesium sensor material are also discussed.

How to well prepare before the start of medical projects of The National Key Research and Development Program of China / 中华医学科研管理杂志

Objective The management of medical projects of the National Key Research and Development Program of China is difficult.Thus this article aims to analyze the common problems and summarize the preparatory work before the project initiation.Methods Comprehensively adopted the methodologies of literature analysis,survey investigation to analyze the common problems before the project initiation,and then particularly summarize the preparatory works for biomedical research,especially for clinical research,from the perspective of investigators.Results Proposed several aspects that should take into consideration before the initiation of the projects..clarify the organizational management framework,play the role of kick-off meeting,organize tailored training on financial management,prepare research protocol and related documents,seek Institutional Review Board approval and conduct clinical research registration,normalize document managment,formulate project management plan,and prepare research facilities timely.Conclusions Investigators should develop a detailed project management plan before initiation of the project,preparation work should focus on personnel,financial resources,facilities,research progress,quality,data,etc.

Three-Dimensional Finite Element Analysis of PEEK Customized Reconstruction Plate for Mandibular Defect / 医用生物力学

Objective To study the stress distributions of mandible defect by reconstruction with polyetheretherketone (PEEK) and its composite reconstruction plate through three-dimensional finite element analysis. Methods The finite element models of reconstruction plate of titanium alloy, PEEK, carbon-fiber-reinforced polyetheretherketone (CFR)-PEEK with 30% endless carbon fibers and CFR-PEEK with 68% endless carbon fibers were established by CBCT scanning，Mimics software，SolidWorks, Geomagic Studio and ANSYS Workbench software, and titanium alloy served as control. Two occlusal situations were simulated in the mandible model. Loading I: anterior region loading with 300 N; loading II: left posterior region with 300 N. Results The ratio of the maximum Von Mises stress of the reconstructed plate to its yield strength under two load situations: PEEK system ＞ 30%CFR-PEEK system ＞ titanium alloy system ＞ 68% CFR-PEEK system; the maximum stress of the mandible: PEEK system ＞ 30% CFR-PEEK system ＞ titanium alloy system ＞ 68% CFR-PEEK system. In the PEEK system, the maximum Von Mises stress of reconstructed plate and mandibular exceeded its yield strength under loading I; in the other systems, the maximum Von Mises stresses of mandible and reconstruction plate were below the yield strength. Conclusions The reconstruction plate of CFR-PEEK with 68% endless carbon fibers distributed the stresses in a similar manner as the titanium reconstruction plate, which could meet the mechanical strength requirements of mandible defect reconstruction. The fracture risk of the reconstructed plate was lower than that of titanium alloy, but the incidence of stress shielding was slightly higher. The result can provide references for the selection of materials and clinical application of reconstruction plate for mandibular defects.

Bone resorption deficiency affects tooth root development in RANKL mutant mice due to attenuated IGF-1 signaling in radicular odontoblasts.

The tooth root is essential for normal tooth physiological function. Studies on mice with mutations or targeted gene deletions revealed that osteoclasts (OCs) play an important role in tooth root development. However, knowledge on the cellular and molecular mechanism underlying how OCs mediate root formation is limited. During bone formation, growth factors (e.g. Insulin-like growth factor-1, IGF-1) liberated from bone matrix by osteoclastic bone resorption stimulate osteoblast differentiation. Thus, we hypothesize that OC-osteoblast coupling may also apply to OC-odontoblast coupling; therefore OCs may have a direct impact on odontoblast differentiation through the release of growth factor(s) from bone matrix, and consequently regulate tooth root formation. To test this hypothesis, we used a receptor activator of NF-κB ligand (RANKL) knockout mouse model in which OC differentiation and function was entirely blocked. We found that molar root formation and tooth eruption were defective in RANKL-/- mice. Disrupted elongation and disorganization of Hertwig's epithelial root sheath (HERS) was observed in RANKL-/- mice. Reduced expression of nuclear factor I C (NFIC), osterix, and dentin sialoprotein, markers essential for radicular (root) odontogenic cell differentiation indicated that odontoblast differentiation was disrupted in RANKL deficient mice likely contributing to the defect in root formation. Moreover, down-regulation of IGF/AKT/mTOR activity in odontoblast indicated that IGF signaling transduction in odontoblasts of the mutant mice was impaired. Treating odontoblast cells in vitro with conditioned medium from RANKL-/- OCs cultured on bone slices resulted in inhibition of odontoblast differentiation. Moreover, depletion of IGF-1 in bone resorption-conditioned medium (BRCM) from wild-type (WT) OC significantly compromised the ability of WT osteoclastic BRCM to induce odontoblast differentiation while addition of IGF-1 into RANKL-/- osteoclastic BRCM rescued impaired odontoblast differentiation, confirming that root and eruption defect in RANKL deficiency mice may result from failure of releasing of IGF-1 from bone matrix through OC bone resorption. These results suggest that OCs are important for odontoblast differentiation and tooth root formation, possibly through IGF/AKT/mTOR signaling mediated by cell-bone matrix interaction. These findings provide significant insights into regulatory mechanism of tooth root development, and also lay the foundation for root regeneration studies.