[Clinical efficacy of intraarticular vancomycin in preventing early periprosthetic joint infection after primary knee arthroplasty]

Objective: To investigate the clinical effect of intraarticular vancomycin on early periprosthetic joint infection (PJI) in knee arthroplasty and the incidence of postoperative complications. Methods: This is a retrospective cohort study. The clinical data of 1 867 patients who underwent primary knee arthroplasty at Department of Joint Surgery, the Affiliated Hospital of Qingdao University from April 2022 to June 2023 were retrospectively analysed, including total knee arthroplasty (TKA), robotic-assisted total knee arthroplasty (RA-TKA) and unicondylar knee arthroplasty (UKA). There were 687 males and 1180 females, aged (68.0±11.2)years(range:45 to 87 years). Patients were divided into the vancomycin group and the control group according to whether or not intra-articular injection of 1 g of vancomycin powder dissolved in 30 ml of saline was performed after intraoperative joint capsule closure. In the vancomycin group, 925 patients were included, including 782 TKA, 27 RA-TKA and 116 UKA.In the control group, 942 patients were included, including 767 TKA, 99 RA-TKA and 76 UKA. Early PJI, wound complications, and vancomycin-related toxicity including acute renal collapse, ototoxicity, and allergic reactions were assessed within 3 months postoperatively. Results: No PJI was found in all patients in the vancomycin group.Five cases (0.7%,5/767) of early PJI were found in TKA patients in the control group, with a statistically significant difference (P=0.030); 1 case of early PJI was found in each RA-TKA and UKA patients, with non-significant difference compared with vancomycin group (all P>0.05). Two cases (0.3%,2/782) of incisional complications were found in TKA patients in the vancomycin group, and 4 cases (0.5%, 4/767) of incisional complications were found in TKA patients in the control group, with non-significant difference(P=0.449); no incisional complications were found in RA-TKA patients in the vancomycin group, and 1 case (1.0%,1/99) of incisional complications were found in RA-TKA patients in the control group, the difference was not statistically significant (P>0.05); no incisional complications were found in both groups of UKA patients.No vancomycin-related acute kidney injury, ototoxicity, or allergic reactions was observed in all patients. Conclusion: Intra-articular injection of 1 g of vancomycin suspension after arthrotomy closure during TKA maybe lower the risk of early PJI without increasing the risk of wound complication and vancomycin-associated systemic toxicity.

[A preliminary in vitro and in vivo study of endothelial cell pyroptosis in the periodontal inflammatory environment]

Objective: To observe whether endothelial cells undergo pyroptosis in the inflammatory periodontal environment by using a model in vivo and in vitro, providing an experimental basis for indepth understanding of the underlying pathogenesis of periodontitis. Methods: According to the classification of periodontal diseases of 2018, gingival tissues were collected from periodontally healthy subjects and patients with stage Ⅲ-Ⅳ, grade C periodontitis, who presented Department of Oral and Maxillofacial Surgery and Department of Periodontology, School of Stomatology, The Fourth Military Medical University from April to May 2022. Immunohistochemical staining was performed to detect the expression level and distribution of gasdermin D (GSDMD), a hallmark protein of cell pyroptosis, in gingival tissues. Periodontitis models were established in each group by ligating the maxillary second molar teeth of three mice for 2 weeks (ligation group). The alveolar bone resorption was determined by micro-CT (mice without ligation treatment were used as the control group), and the colocalization of GSDMD and CD31 were quantitatively analyzed by immunofluorescence staining in gingival tissues of healthy and inflammatory mice. Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and treated with lipopolysaccharide (LPS) of Porphyromonas gingivalis (Pg) combined with adenosine triphosphate (ATP) at various concentrations of 0.5, 1.0, 2.5, 5.0, and 10.0 mg/L, respectively, and the 0 mg/L group was set as the control group at the same time. Scanning electron microscopy was used to observe the morphology of HUVECs. Western blotting was used to detect the expression of gasdermin D-N terminal domains (GSDMD-N) protein and immunofluorescence cell staining was used to detect the expression and distribution of GSDMD. Cell counting kit-8 (CCK-8) was used to detect the proliferative ability of HUVECs, and propidium iodide (PI) staining was used to detect the integrity of cell membrane of HUVECs. Results: Immunohistochemistry showed that GSDMD in gingival tissues of periodontitis was mainly distributed around blood vessels and its expression level was higher than that in healthy tissues. Micro-CT showed that alveolar bone resorption around the maxillary second molar significantly increased in ligation group mice compared with control subjects (t=8.88, P<0.001). Immunofluorescence staining showed significant colocalization of GSDMD with CD31 in the gingival vascular endothelial cells in mice of ligation group. The results of scanning electron microscopy showed that there were pores of different sizes, the typical morphology of pyroptosis, on HUVECs cell membranes in the inflammatory environment simulated by ATP combined with different concentrations of LPS, and 2.5 mg/L group showed the most dilated and fused pores on cell membranes, with the cells tended to lyse and die. Western blotting showed that the expression of GSDMD-N, the hallmark protein of cell pyroptosis, was significantly higher in 2.5 and 5.0 mg/L groups than that in the control group (F=3.86, P<0.01). Immunofluorescence cell staining showed that the average fluorescence intensity of GSDMD in 2.5 mg/L group elevated the most significantly in comparison with that in the control group (F=35.25, P<0.001). The CCK-8 proliferation assay showed that compared to the control group (1.00±0.02), 0.5 mg/L (0.52±0.07), 1.0 mg/L (0.57±0.10), 2.5 mg/L (0.58±0.04), 5.0 mg/L (0.55±0.04), 10.0 mg/L (0.61±0.03) groups inhibited cell proliferation (F=39.95, P<0.001). PI staining showed that the proportion of positive stained cells was highest [(56.07±3.22)%] in 2.5 mg/L group (F=88.24, P<0.001). Conclusions: Endothelial cells undergo significant pyroptosis in both and periodontal inflammatory environments, suggesting that endothelial cell pyroptosis may be an important pathogenic factor contributing to the pathogenesis of periodontitis.

Dynamics of the Deformable Fluid Interface Interacting with an Approaching Solid under the Electrostatic Field

A theoretical model was developed to describe the dynamics of a deformable fluid interface interacting with an approaching solid without contact by both the attractive electrostatic and van der Waals (i.e., vdW) interaction, analogous to the situation in the experiments by electric force microscopy (i.e., EFM) or electric-surface force apparatus (i.e., E-SFA) involved in the soft fluid interface. On the basis of this model, a numerical study of the deformation of the fluid interface, the force-vs-separation behavior, and the critical limiting conditions of contact has systematically been carried out. Our results show that the surface pressure induced by the electrostatic interaction plays a more prominent role in the deformation of the fluid interface than the vdW interaction does, and there exists a principal length scale associated with the relative strength of the electrostatic field to the surface tension, affecting the fluid interface shape under the electrostatic field. It was also shown that both the force-distance curves and the corresponding curves of fluid interface deformation peak versus distance for various electrostatic fields satisfy the universal scaling power law. Moreover, an analytical solution to the Euler-Lagrange differential equation governing the deformation of the fluid interface under the external electric field is obtained, and two extended formulas for explicitly describing the principal length scales that respectively characterize the lateral and longitudinal deformations of the fluid interface were determined.

Voltage-Controlled Magnon Transistor via Tuning Interfacial Exchange Coupling

Magnon transistors that can effectively regulate magnon transport by an electric field are desired for magnonics, which aims to provide a Joule-heating free alternative to the conventional electronics owing to the electric neutrality of magnons (the key carriers of spin-angular momenta in the magnonics). However, also due to their electric neutrality, magnons have no access to directly interact with an electric field and it is thus difficult to manipulate magnon transport by voltages straightforwardly. Here, we demonstrated a gate voltage (V_{g}) applied on a nonmagnetic metal and magnetic insulator (MI) interface that bent the energy band of the MI and then modulated the probability for conduction electrons in the nonmagnetic metal to tunnel into the MI, which can consequently enhance or weaken the spin-magnon conversion efficiency at the interface. A voltage-controlled magnon transistor based on the magnon-mediated electric current drag (MECD) effect in a Pt-Y_{3}Fe_{5}O_{12}-Pt sandwich was then experimentally realized with V_{g} modulating the magnitude of the MECD signal. The obtained efficiency (the change ratio between the MECD voltage at ±V_{g}) reached 10%/(MV/cm) at 300 K. This prototype of magnon transistor offers an effective scheme to control magnon transport by a gate voltage.

LSD1 inhibition suppresses ASCL1 and de-represses YAP1 to drive potent activity against neuroendocrine prostate cancer

Lysine-specific demethylase 1 (LSD1 or KDM1A ) has emerged as a critical mediator of tumor progression in metastatic castration-resistant prostate cancer (mCRPC). Among mCRPC subtypes, neuroendocrine prostate cancer (NEPC) is an exceptionally aggressive variant driven by lineage plasticity, an adaptive resistance mechanism to androgen receptor axis-targeted therapies. Our study shows that LSD1 expression is elevated in NEPC and associated with unfavorable clinical outcomes. Using genetic approaches, we validated the on-target effects of LSD1 inhibition across various models. We investigated the therapeutic potential of bomedemstat, an orally bioavailable, irreversible LSD1 inhibitor with low nanomolar potency. Our findings demonstrate potent antitumor activity against CRPC models, including tumor regressions in NEPC patient-derived xenografts. Mechanistically, our study uncovers that LSD1 inhibition suppresses the neuronal transcriptional program by downregulating ASCL1 through disrupting LSD1:INSM1 interactions and de-repressing YAP1 silencing. Our data support the clinical development of LSD1 inhibitors for treating CRPC - especially the aggressive NE phenotype.

Statement of Significance

Neuroendocrine prostate cancer presents a clinical challenge due to the lack of effective treatments. Our research demonstrates that bomedemstat, a potent and selective LSD1 inhibitor, effectively combats neuroendocrine prostate cancer by downregulating the ASCL1- dependent NE transcriptional program and re-expressing YAP1.

[Effects of immune responses mediated by topological structures of three-dimensional bioprinted scaffolds on hair follicle cycle in mice]

Objective: To explore the effects of the immune responses mediated by topological structures of three-dimensional bioprinted scaffolds on hair follicle cycle in mice. Methods: The study was an experimental research. The alginate-gelatin composite hydrogels were printed into scaffolds using a three-dimensional bioprinter and named T45 scaffolds, T60 scaffolds, and T90 scaffolds according to the 3 topological structures of the scaffolds (the rotation angles of the printhead during printing were 45°, 60°, and 90°, respectively), and the morphology of the three scaffolds was observed after cross-linking by naked eyes. Nine 8-week-old female C57BL/6J mice were divided into T45 group, T60 group, and T90 group, according to the random number table, with three mice in each group, and the T45, T60, and T90 scaffolds were subcutaneously implanted on the back of mice, respectively. On post implantation day (PID) 7, the hair growth in the dorsal depilated area of mice was observed, the thickness of the fiber capsule around the scaffolds was observed by hematoxylin-eosin staining, and the expression levels of CD68, bone morphogenetic protein-2 (BMP-2), and tumor necrosis factor (TNF) protein in the tissue surrounding the scaffolds were observed by immunofluorescence staining. The samples of the above experiments were all 3. Results: The topological structures of the three scaffolds were all clear with high fidelity after cross-linking. On PID 7, the hair growth was obvious in the dorsal depilated area of mice in T45 group and T90 group, while hair growth was slow in the scaffold implantation area of mice in T60 group, which was significantly different from that of the unimplanted area. On PID 7, compared with (18±4) μm in T90 group, the thickness of both the fiber capsule around the scaffolds ((39±4) and (55±8) μm) of mice in T45 group and T60 group was significantly increased (P<0.05); the thickness of the fiber capsule around the scaffolds of mice in T60 group was also significantly increased compared with that in T45 group (P<0.05). On PID 7, the expression level of CD68 protein in the tissue surrounding the scaffolds of mice in T60 group was significantly higher than the levels in T45 group and T90 group (with both P values <0.05). The expression level of BMP-2 protein in the tissue surrounding the scaffolds of mice in T60 group was significantly higher than the levels in T45 group and T90 group (with both P values <0.05), and the expression level of BMP-2 protein in the tissue surrounding the scaffolds of mice in T45 group was significantly higher than that in T90 group (P<0.05). The expression level of TNF protein in the tissue surrounding the scaffolds of mice in T60 group was significantly lower than the levels in T45 group and T90 group (with both P values <0.05). Conclusions: Three-dimensional bioprinted scaffolds with different topological structures mediate different degrees of immune responses after being implanted in mice. A moderate immune response promotes hair growth in depilated area of mice, while an excessive immune response results inhibits the hair follicle entering into the anagen phase.

Binding interaction of environmental DNA with typical emerging perfluoroalkyl acids and its impact on bioavailability

As the replacement compounds of perfluoroalkyl acids (PFAAs), emerging PFAAs generally exhibit equal or more hazardous toxicity than legacy PFAAs. Numerous DNA as environmental organic matters coexists with emerging PFAAs, but their interactions and the resulting interaction impacts on the bioavailability of emerging PFAAs remain insufficiently understood. Here, we studied the binding strength and mechanism between DNA and emerging PFAAs (perfluorobutyric acid, perfluorobutylsulfonic acid, and hexafluoropropylene oxide dimer acid) using perfluorooctanoic acid as the control, and further investigated the impacts of DNA binding on the bioavailability of the emerging PFAAs. Isothermal titration calorimetry and quantum chemical calculation found that the emerging PFAAs could bind with DNA bases (main thymine) by van der Waals force and halogen-bond, showing the binding affinities in the range of 7.87 × 104 to L/mol to 6.54 × 106 L/mol. The PFAAs-DNA binding significantly decreased the bioavailability of the PFAAs in both seedlings and plants of pakchoi (Brassica chinensis L.), with little differences in bioavailability change extent among PFAAs. The findings highlight the universality and similarity of the DNA binding effects on PFAAs bioavailability, which can be the natural detoxification mechanism for response to the PFAAs pollution.

[Safety of double and a half layered esophagojejunal anastomosis in radical gastrectomy: A prospective, multi-center, single arm trial]

Objective: To evaluate the safety of double and a half layered esophagojejunal anastomosis in radical gastrectomy. Methods: This prospective, multi-center, single-arm study was initiated by the Affiliated Cancer Hospital of Zhengzhou University in June 2021 (CRAFT Study, NCT05282563). Participating institutions included Nanyang Central Hospital, Zhumadian Central Hospital, Luoyang Central Hospital, First Affiliated Hospital of Henan Polytechnic University, First Affiliated Hospital of Henan University, Luohe Central Hospital, the People's Hospital of Hebi, First People's Hospital of Shangqiu, Anyang Tumor Hospital, First People's Hospital of Pingdingshan, and Zhengzhou Central Hospital Affiliated to Zhengzhou University. Inclusion criteria were as follows: (1) gastric adenocarcinoma confirmed by preoperative gastroscopy;(2) preoperative imaging assessment indicated that R0 resection was feasible; (3) preoperative assessment showed no contraindications to surgery;(4) esophagojejunostomy planned during the procedure; (5) patients volunteered to participate in this study and gave their written informed consent; (6) ECOG score 0-1; and (7) ASA score I-III. Exclusion criteria were as follows: (1) history of upper abdominal surgery (except laparoscopic cholecystectomy);(2) history of gastric surgery (except endoscopic submucosal dissection and endoscopic mucosal resection); (3) pregnancy or lactation;(4) emergency surgery for gastric cancer-related complications (perforation, hemorrhage, obstruction); (5) other malignant tumors within 5 years or coexisting malignant tumors;(6) arterial embolism within 6 months, such as angina pectoris, myocardial infarction, and cerebrovascular accident; and (7) comorbidities or mental health abnormalities that could affect patients' participation in the study. Patients were eliminated from the study if: (1) radical gastrectomy could not be completed; (2) end-to-side esophagojejunal anastomosis was not performed during the procedure; or (3) esophagojejunal anastomosis reinforcement was not possible. Double and a half layered esophagojejunal anastomosis was performed as follows: (1) Open surgery: the full thickness of the anastomosis is continuously sutured, followed by embedding the seromuscular layer with barbed or 3-0 absorbable sutures. The anastomosis is sutured with an average of six to eight stitches. (2) Laparoscopic surgery: the anastomosis is strengthened by counterclockwise full-layer sutures. Once the anastomosis has been sutured to the right posterior aspect of the anastomosis, the jejunum stump is pulled to the right and the anastomosis turned over to continue to complete reinforcement of the posterior wall. The suture interval is approximately 5 mm. After completing the full-thickness suture, the anastomosis is embedded in the seromuscular layer. Relevant data of patients who had undergone radical gastrectomy in the above 12 centers from June 2021 were collected and analyzed. The primary outcome was safety (e.g., postoperative complications, and treatment). Other studied variables included details of surgery (e.g., surgery time, intraoperative bleeding), postoperative recovery (postoperative time to passing flatus and oral intake, length of hospital stay), and follow-up conditions (quality of life as assessed by Visick scores). Result: [1] From June 2021 to September 2022,457 patients were enrolled, including 355 men and 102 women of median age 60.8±10.1 years and BMI 23.7±3.2 kg/m2. The tumors were located in the upper stomach in 294 patients, mid stomach in 139; and lower stomach in 24. The surgical procedures comprised 48 proximal gastrectomies and 409 total gastrectomies. Neoadjuvant chemotherapy was administered to 85 patients. Other organs were resected in 85 patients. The maximum tumor diameter was 4.3±2.2 cm, number of excised lymph nodes 28.3±15.2, and number of positive lymph nodes five (range one to four. As to pathological stage,83 patients had Stage I disease, 128 Stage II, 237 Stage III, and nine Stage IV. [2] The studied surgery-related variables were as follows: The operation was successfully completed in all patients, 352 via a transabdominal approach, 25 via a transhiatus approach, and 80 via a transthoracoabdominal approach. The whole procedure was performed laparoscopically in 53 patients (11.6%), 189 (41.4%) underwent laparoscopic-assisted surgery, and 215 (47.0%) underwent open surgery. The median intraoperative blood loss was 200 (range, 10-1 350) mL, and the operating time 215.6±66.7 minutes. The anastomotic reinforcement time was 2 (7.3±3.9) minutes for laparoscopic-assisted surgery, 17.6±1.7 minutes for total laparoscopy, and 6.0±1.2 minutes for open surgery. [3] The studied postoperative variables were as follows: The median time to postoperative passage of flatus was 3.1±1.1 days and the postoperative gastrointestinal angiography time 6 (range, 4-13) days. The median time to postoperative oral intake was 7 (range, 2-14) days, and the postoperative hospitalization time 15.8±6.7 days. [4] The safety-related variables were as follows: In total, there were 184 (40.3%) postoperative complications. These comprised esophagojejunal anastomosis complications in 10 patients (2.2%), four (0.9%) being anastomotic leakage (including two cases of subclinical leakage and two of clinical leakage; all resolved with conservative treatment); and six patients (1.3%) with anastomotic stenosis (two who underwent endoscopic balloon dilation 21 and 46 days after surgery, the others improved after a change in diet). There was no anastomotic bleeding. Non-anastomotic complications occurred in 174 patients (38.1%). All patients attended for follow-up at least once, the median follow-up time being 10 (3-18) months. Visick grades were as follows: Class I, 89.1% (407/457); Class II, 7.9% (36/457); Class III, 2.6% (12/457); and Class IV 0.4% (2/457). Conclusion: Double and a half layered esophagojejunal anastomosis in radical gastrectomy is safe and feasible.

Active control on topological interface states of elastic wave metamaterials with double coupled chains

Topological elastic wave metamaterials have shown significant advantages in manipulating wave propagation and realizing localized modes. However, topological properties of most mechanical metamaterials are difficult to change because of structural limitations. This work proposes the elastic wave metamaterials with double coupled chains and active control, in which band inversion and topological interface modes can be achieved by flexibly tuning negative capacitance circuits. Finite element simulations and experiments are performed to demonstrate the topological interface modes, which show good agreements with the theoretical results. This research seeks to provide effective strategies for the design and application of topological elastic wave metamaterials.

[The value of dynamic contrast-enhanced MRI in the differentiation between benign and malignant lacrimal epithelial tumors]

Objective: To investigate the diagnostic performance of multiparametric dynamic contrast-enhanced MRI(DCE-MRI) for the differentiation between benign and malignant larcrimal gland epithelial tumors. Methods: The clinical and imaging data of 104 patients with epithelial tumors of the lacrimal gland who underwent orbital MRI scan and met the inclusion criteria in Beijing Tongren Hospital from January 2011 to December 2017 were retrospectively collected, including 48 males and 56 females, aged from 12 to 77 (43±7) years. Sixty-three cases of benign epithelial tumors and 41 cases of malignant epithelial tumors were examined by DCE-MRI. The parameters of semiquantitative analysis including: time to peak enhancement (Tpeak), maximum enhancement ratio (ERmax), Slope, washout ratio (WR) and time-signal intensity curve (TIC) types. The parameters of quantitative analysis including: volume transfer constant (Ktrans), the extravascular extracellular volume fraction (Ve) and rate constant (Kep). Receiver operating characteristic (ROC) curve analysis was performed for DCE-MRI parameters with statistically significant differences, the area under the curve (AUC) was calculated, the diagnostic threshold was determined, and the diagnostic performance was evaluated. Logistic regression analysis was used to determine the best parameters for differential diagnosis of benign and malignant epithelial tumors of the lacrimal gland. Results: For the semiquantitative analysis of DCE-MRI, malignant lacrimal gland epithelial tumor had a significantly shorter Tpeak than benign masses [(103.77±57.87) s vs (187.80±77.01) s,P<0.001)], while had a higher value in ERmax, Slope [M(Q1,Q3)] and WR in malignant masses compared with benign one [1.55±0.39 vs 1.36±0.33; 1.76 (0.97,2.27) vs 0.62 (0.50,0.93); 7.70%(1.40%, 21.60%)% vs 0(0, 0),all P<0.05)].The TICs of benign lacrimal tumors mainly showed a persistent type (49/63),while most malignant lacrimal tumors mainly showed a plateau type (25/41). For the quantitative analysis of DCE-MRI, the values of Ktrans and Kep[M(Q1,Q3)] in malignant tumors were significantly greater than those of benign tumors (0.99±0.52/min vs 0.43±0.23/min, P<0.001; 1.33(0.83, 1.55)/min vs 0.55(0.46, 0.68)/min, P<0.001). No significant difference in Ve was found between the groups (0.76±0.20 vs 0.73±0.22,P=0.467). Through the statistical analysis, TIC types (OR=3.887,95%CI: 1.409-10.725) and Ktrans(OR=50.979,95%CI: 6.046-429.830) can provide superior diagnostic performance for predicting malignant lacrimal gland epithelial tumors, with a sensitivity of 78.05%, specificity of 77.78%,and sensitivity of 70.73%, specificity of 95.24%, respevtively. Furthermore, the comprehensive diagnostic performance of Ktrans in AUC was proven to be significantly better than that of TIC [0.875 (0.796-0.932) vs 0.798 (0.708-0.870),P=0.049]. Conclusions: Multiparametric DCE-MRI is helpful for the differential diagnosis of benign and malignant epithelial tumors of lacrimal gland. TIC type and Ktrans have higher diagnostic value, and the diagnostic performance of Ktrans is better than that of TIC.

[Multi-omics approaches for revealing the etiology of cancer: from genomics, exposomics, metabolomics to system epidemiology]

Identifying risk factors of the disease are one of the main tasks of epidemiology. With the advancement of omics technologies (e.g., genome, transcriptome, proteome, metabolome, and exposome), cancer etiology research has entered the stage of systems epidemiology. Genomic research identifies cancer susceptibility loci and uncovers their biological mechanisms. Exposomic research investigates the impact of environmental factors on biological processes and disease risks. The metabolome is downstream of biological regulatory networks, reflecting the effects of the gene, environment, and their interactions, which can help elucidate the biological mechanisms of genetic and environmental risk factors and identify new biomarkers. Here, we reviewed the applications of genomic, exposomic, and metabolomic studies in the etiologic research on cancer. We summarized the importance of multi-omics approaches and systems epidemiology in cancer etiology research and outlined future perspectives.

[Revision rate of periprosthetic joint infection post total hip or knee arthroplasty of 34 hospitals in China between 2015 and 2017: a multi-center survey]

Objective: To investigate the rate of periprosthetic joint infection (PJI) revision surgeries and clinical information of hip-/knee- PJI cases nationwide from 2015 to 2017 in China. Methods: An epidemiological investigation. A self-designed questionnaire and convenience sampling were used to survey 41 regional joint replacement centers nationwide from November 2018 to December 2019 in China. The PJI was diagnosed according to the Musculoskeletal Infection Association criteria. Data of PJI patients were obtained by searching the inpatient database of each hospital. Questionnaire entries were extracted from the clinical records by specialist. Then the differences in rate of PJI revision surgery between hip- and knee- PJI revision cases were calculated and compared. Results: Total of 36 hospitals (87.8%) nationwide reported data on 99 791 hip and knee arthroplasties performed from 2015 to 2017, with 946 revisions due to PJI (0.96%). The overall hip-PJI revision rate was 0.99% (481/48 574), and it was 0.97% (135/13 963), 0.97% (153/15 730) and 1.07% (193/17 881) in of 2015, 2016, 2017, respectively. The overall knee-PJI revision rate was 0.91% (465/51 271), and it was 0.90% (131/14 650), 0.88% (155/17 693) and 0.94% (179/18 982) in 2015, 2016, 2017, respectively. Heilongjiang (2.2%, 40/1 805), Fujian (2.2%, 45/2 017), Jiangsu (2.1%, 85/3 899), Gansu (2.1%, 29/1 377), Chongqing (1.8%, 64/3 523) reported relatively high revision rates. Conclusions: The overall PJI revision rate in 34 hospitals nationwide from 2015 to 2017 is 0.96%. The hip-PJI revision rate is slightly higher than that in the knee-PJI. There are differences in revision rates among hospitals in different regions.

[Risk factors analysis on high-risk behaviors of drowning among students in Shufu county, Kashgar area, Xinjiang Uygur Autonomous Region]

Objective: To understand the incidence and risk factors of high-risk drowning behaviors among primary and middle school students in Shufu county, Kashgar area, Xinjiang Uygur Autonomous Region, and provide a theoretical basis for the development of drowning prevention policies and intervention measures. Methods: Cluster random sampling method was adopted in Bulakesu and Uppal of Shufu county. A total of 28 primaries and 2 middle schools were selected, and questionnaires surveyed all the students in grades 1-8. Results: A total of 14 543 questionnaires were sent out. 23.9% of primary and secondary school students had experienced high-risk drowning behavior in the past 12 months. Higher swimming level, introversion, intense curiosity, poor relationship with classmates, poor relationship with family, and open water near the school and open water near home were the risk factors of high-risk drowning behaviors. Conclusions: More attention should be paid to the psychology and high-risk behaviors of primary and middle school students, and the education of drowning knowledge and skills should be strengthened. Meanwhile, schools and communities should pay attention to the management and intervention of open water.

[Clinical characteristics of 272 437 patients with different histopathological subtypes of primary esophageal malignant tumors]

Objective: To characterize the histopathological subtypes and their clinicopathological parameters of gender and onset age by common, rare and sparse primary esophageal malignant tumors (PEMT). Methods: A total of 272 437 patients with PEMT were enrolled in this study, and all of the patients were received radical surgery. The clinicopathological information of the patients was obtained from the database established by the State Key Laboratory of Esophageal Cancer Prevention & Treatment from September 1973 to December 2020, which included the clinical treatment, pathological diagnosis and follow-up information of esophagus and gastric cardia cancers. All patients were diagnosed and classified by the criteria of esophageal tumor histopathological diagnosis and classification (2019) of the World Health Organization (WHO). The esophageal tumors, which were not included in the WHO classification, were analyzed separately according to the postoperative pathological diagnosis. The χ² test was performed by the SPSS 25.0 software on count data, and the test standard α=0.05. Results: A total of 32 histopathological types were identified in the enrolled PEMT patients, of which 10 subtypes were not included in the WHO classification. According to the frequency, PEMT were divided into common (esophageal squamous cell carcinoma, ESCC, accounting for 97.1%), rare (esophageal adenocarcinoma, EAC, accounting for 2.3%) and sparse (mainly esophageal small cell carcinoma, malignant melanoma, etc., accounting for 0.6%). All the common, rare, and sparse types occurred predominantly in male patients, and the gender difference of rare type was most significant (EAC, male∶ female, 2.67∶1), followed with common type (ESCC, male∶ female, 1.78∶1) and sparse type (male∶ female, 1.71∶1). The common type (ESCC) mainly occurred in the middle thoracic segment (65.2%), while the rare type (EAC) mainly occurred in the lower thoracic segment (56.8%). Among the sparse type, malignant melanoma and malignant fibrous histiocytoma were both predominantly located in the lower thoracic segment (51.7%, 66.7%), and the others were mainly in the middle thoracic segment. Conclusion: ESCC is the most common type among the 32 histopathological types of PEMT, followed by EAC as the rare type, and esophageal small cell carcinoma and malignant melanoma as the major sparse type, and all of which are mainly occur in male patients. The common type of ESCC mainly occur in the middle thoracic segment, while the rare type of EAC mainly in the lower thoracic segment. The mainly sparse type of malignant melanoma and malignant fibrous histiocytoma predominately occur in the lower thoracic segment, and the remaining sparse types mainly occur in the middle thoracic segment.

[Research advances on the characteristics of fibroblast in keloid]

In re-cent 20 years, the development of cell biology technology has promoted the research of keloid. Keloid fibroblasts (KFbs) are the main effector cells in keloid, which are closely related to the occurrence and development of keloid. It is significantly different in terms of biological characteristics and gene expression between KFbs and normal fibroblasts. This articles reviews the characteristics of KFbs from multiple perspectives, describing its biological character- istics in details including microstructures, metabolic character- istics, and proliferation properties, and introducing the main characteristics of heterogeneity and genomics of KFbs. The further research on KFbs will help to elucidate the pathogenesis of keloids and provide valuable strategies for the prevention and treatment of keloids.

[Clinicopathological features of hepatic fibrinogen storage disease in children]

Objective: To investigate the clinicopathological and molecular characteristics of hepatic fibrinogen storage disease (FSD) in children. Methods: The clinical, histopathologic, immunophenotypic, ultrastructural and gene sequencing data of 4 FSD cases were collected from September 2019 to January 2021 in the Children's Hospital of Fudan University, Shanghai, China. Retrospective analysis and literature review were conducted. Results: There were 4 cases of FSD, 3 males and 1 female, aged 3 years and 3 months to 6 years (median age, 3 years and 4 months). The clinical manifestations were abnormal liver function and abnormal blood coagulation function, for which 2 cases had family genetic history. Liver biopsies revealed that, besides liver steatosis, fibrosis and inflammation, there were single or multiple eosinophilic inclusion bodies of various sizes and surrounding transparent pale halo in hepatocytes. Immunohistochemistry showed that the inclusion bodies were positive for anti-fibrinogen. Under the electron microscope, they corresponded to the dilated cisternae of the rough endoplasmic reticulum, which were occupied by compactly packed tubular structures and arranged into a fingerprint-like pattern with curved bundles. Gene sequencing revealed that the 2 cases of FGG mutation were located in exon 8 c.1106A>G (p.His369Arg) and c.905T>C (p.Leu302Pro), and 1 case was located in exon 9 c.1201C>T (p.Arg401Trp). No pathogenic variant was detected in the other case. Conclusions: FSD is a rare genetic metabolic disease and clinically manifests as abnormal liver function with hypofibrinogenemia. In the background of liver steatosis, fibrosis and inflammation, there are eosinophilic inclusions with pale halo in the hepatocytic cytoplasm, which can be identified by anti-fibrinogen immunohistochemical staining. The fingerprint-like structures under electron microscope are helpful for the diagnosis, while FGG sequencing detects the pathogenic mutation of exon 8 or 9 that can clearly explain the phenotype. However, the diagnosis of FSD cannot be completely ruled out if the relevant mutations are not detected.

[Establishment and application of a nomogram model for prognostic risk prediction in patients with epithelial ovarian cancer]

Objective: To explore the prognostic factors of epithelial ovarian carcinoma (EOC), construct a nomogram model, and evaluate the prognosis of EOC patients. Methods: A retrospective analysis was performed on clinicopathological data of 208 cases of EOC patients who received initial treatment in the First Affiliated Hospital of Army Medical University from August 11, 2016 to July 11, 2018, including age, preoperative ascites, preoperative neoadjuvant chemotherapy, surgical method, pathological type, pathological differentiation degree, surgical pathology stage, preoperative and post-chemotherapy serum cancer antigen 125 (CA₁₂₅) level, human epididymal protein 4 (HE4) level, platelet count and platelet/lymphocyte number ratio (PLR). The univariate and multivariate Cox risk ratio models were used to analyze the related factors affecting progression free survival (PFS) in EOC patients, and the prediction nomogram of PFS in EOC patients was established to evaluate its efficacy in predicting PFS. Results: Univariate analysis showed that preoperative neoadjuvant chemotherapy, pathological type, pathological differentiation degree, surgical pathology stage, serum CA₁₂₅ and HE4 level before operation and after chemotherapy, platelet count and PLR before operation and after chemotherapy were significantly correlated with PFS in EOC patients (all P<0.05). Multivariate analysis showed that surgical pathology stage, preoperative PLR, serum CA₁₂₅ and HE4 level after chemotherapy were independent prognostic factors affecting PFS of EOC patients (all P<0.01). The index coefficient of the prediction model for the prognosis of EOC patients established by this method was 0.749 (95% CI: 0.699-0.798), which had good prediction ability, and could help clinicians to more accurately evaluate the prognosis of EOC patients. Conclusion: The nomogram model constructed based on surgical pathology stage, preoperative PLR, serum CA₁₂₅ and HE4 level after chemotherapy could effectively predict the PFS of EOC patients after initial treatment, could help clinicians to screen high-risk patients, provide individualized treatment, and improve the prognosis of EOC patients.

Nonlinear solitary waves in particle metamaterials with local resonators

In this work, solitary wave solutions of particle mechanical metamaterials are studied, in which the mass-in-mass structure with local resonators is considered. The Hertzian contact theory is used to describe adjacent particles in a precompressed granular chain. The governing wave equations are decoupled, and the expressions of bright, dark, and peaked solitary waves are derived, respectively. According to the results, both the wave velocity and prestress can affect the propagation of solitary waves. The amplitudes of bright and peaked solitary waves are smaller when a larger prestress is applied, which are different from the dark solitons. Furthermore, the wave widths become larger as the prestress increases.

[The stability and repeatability of radiomics features based on lung diffusion-weighted imaging]

Objective: To evaluate the feasibility, robustness and reproducibility of radiomics features derived from lung diffusion-weighted imaging (DWI). Methods: Thirty patients with pulmonary nodules/masses who underwent magnetic resonance imaging examination in the Department of Radiology, the First Affiliated Hospital of Guangzhou Medical University, from January 4 2019 to May 5 2019, including 16 males and 14 females, aged from 27 to 69 (57±11) years, were prospectively collected. Planar echo imaging (EPI) -DWI and fast spin-echo (TSE) -DWI scans were performed under free-breathing conditions. Each scan was repeated at an interval of 5 minutes, and the corresponding apparent diffusion coefficient (ADC) maps were reconstructed. Each DWI and ADC sequence (a total of eight groups of images) were manually segmented by two radiologists, and a total of 396 radiomics features in 6 categories were extracted from each group of images. Consistency correlation coefficient (CCC) and dynamic range (DR) were used to evaluate the robustness of features between two scans, and stable features were defined as both CCC values and DR values ≥0.85. Intra-observer and interobserver reproducibility were evaluated by intra-group correlation coefficient (ICC), and ICC values≥0.75 was considered to be good reproducibility. Results: Regardless of EPI or TSE technique, the number of robust features extracted fromDWI (TSE: n=197, EPI: n=169) were higher than that of the corresponding ADC (TSE: n=126, EPI: n=148). The proportion of robust features of TSE-DWI、EPI-DWI、TSE-ADC、EPI-ADC was 49.7% (197/396), 42.7% (169/396), 31.8% (126/396) and 37.4% (148/396), respectively. Of the 396 features, 54 (13.6%) of them demonstrated great robustness (CCC and DR≥0.85) and interobserver and interobserver reproducibility (ICC≥0.75) across all sequences. Conclusions: Radiomics features derived from lung DWI showed robustness and reproducibility. Different sequences and different feature clusters have different proportions of stable features, and some features have good robustness and reproducibility between different scans, different observers, and even different sequences.

Broadband square cloak in elastic wave metamaterial plate with active control

Cloaking invisibility is a novel technique that prevents the object from being detected in the background field. The development of new artificial materials and structures promotes the emergence of new achievements in cloaking research. In this work, a broadband square cloaking configuration of elastic wave metamaterial plate is designed and fabricated by the external active control system. The approximate parameters of the flexural wave cloak can be obtained by the coordinate transformation and achieved by alternating layers of the Acrylonitrile Butadiene Styrene (ABS), polydimethylsiloxane (PDMS), and piezoelectric (PZT) patches. With the introduction of active control systems, the square cloak has a wide effective frequency range. The simulation and experimental results show that the square cloak of flexural waves exhibits a good invisible performance in the frequency region of 500-2200 Hz. Compared to the structure without active control systems, the frequency region 2200-2750 Hz is extended for the active cloak. The design and fabrication of the broadband cloak is wished to be helpful during the practical engineering.

[Clinical features and prognostic analysis of hepatoblastoma in children under six years old]

Objective: To summarize and analyze the clinical features, treatment effects and related factors affecting the prognosis of hepatoblastoma (HB) in children under six years old. Methods: Clinical data of 382 children with HB under six years old who were pathologically diagnosed at the Pediatric Single Center of Beijing Tongren Hospital from May 2005 to May 2019 were analyzed retrospectively. The factors affecting the treatment effect and survival rate of HB were analyzed. The independent risk factors affecting the prognosis of HB were studied by Cox regression model. The χ(2) test was used to compare the enumeration data between groups. Kaplan-Meier method was used for survival analysis. Log-rank test was used to compare the survival rates among subgroups. Results: Children enrolled were with median age of 1.75 (0.08 ~ 5.92) years old and a male to female ratio of 1.5. Alpha-fetoprotein (AFP) median level was 197 406.5 μg/L at initial diagnosis, and the pathological tissue type was mainly epithelial (55.8%). Preoperative PRETEXT stage was mostly stage III (58.6%). 86 cases (22.5%) had portal vein or hepatic vein, and vena cava invasion. 73 cases (19.1%) had extrahepatic adjacent tissues and organs invasion. Twenty-four cases (6.3%) had tumor rupture and bleeding. 171 cases (44.8%) had distant metastases, and 96 cases (25.1%) had multiple intrahepatic lesions. Patients were followed-up to May 2020 (median follow-up time was 56 months). After comprehensive treatment, 218 cases were completely relieved, and 69 cases were partially relieved, and the treatment efficiency was 75.1%. Kaplan-Meier survival analysis showed that the 1, 3, and 5-years overall survival rates (OS) were 93.7%, 84.0%, and 73.9%, respectively, and the event-free survival rates were 90.5%, 79.2%, and 67.5%, respectively. Comparison of the clinical factors of 5-year OS showed that AFP < 100 μg/L (HR = 3.341, P = 0.005), PRETEXT stage IV (HR = 4.026, P = 0.001), vascular invasion (HR = 2.178, P = 0.019) and distant metastasis (HR = 2.634, P = 0.010) were independent risk factors in each subgroup affecting the prognosis of children with HB, and the difference was statistically significant. Conclusion: HB prognosis is related to AFP level, PRETEXT stage, presence or absence of vascular invasion and distant metastasis. Therefore, its survival and prognosis will be different in the presence of different risk factors.

[Analysis of the relationship between the anatomical location of intrapulmonary metastatic lymph nodes and relapse risk and survival in patients with N1 non-small cell lung cancer]

Objective: To evaluate the relationship between the anatomical location of intrapulmonary metastatic lymph nodes and relapse risk and survival in patients with N1 non-small cell lung cancer(NSCLC). Methods: A retrospective analysis of the clinical and pathological data of 138 patients with completely resected N1 NSCLC was conducted. There were 79 males and 59 females, aged from 26 to 81 years with an average of (59±10) years. All of them were treated in the Department of Thoracic Surgery Ⅱ of Peking University Cancer Hospital between January 2007 and December 2015. Patients were stratified based on the 8th edition of the American Joint Committee on Cancer (AJCC) N1 classification and the modified pathological N1 classification strategy, respectively. According to modified pathological N1 classification strategy, which was defined based on the anatomical location of intrapulmonary metastatic lymph nodes, N1 nodes were subcategorized into the hilar (stations 10-11, mN1b) (n=36) and peripheral (stations 12-14, mN1a) (n=102) zones. The Kaplan-Meier curves were plotted to compare the relapse risk and survival analysis, disease-free survival (DFS), and overall survival (OS) were compared between the two staging methods through univariate and multivariate analysis to evaluate the effectiveness of the two classifications in stratifying patients with distinct risks of disease relapse and survival. Results: According to the modified N1 classification, the differences in 5-year DFS and OS between the subgroups (mN1a vs mN1b) were statistically significant(59.5% vs 35.7%; 81.2% vs 56.0%; both P<0.05). However, following the 8th edition of the AJCC N1 classification, no significant differences were found in DFS and OS between the subgroups (both P>0.05). Multivariate analysis showed that the modified N1 classification was an independent prognostic factor to DFS (HR=1.814, 95%CI: 1.005-3.275) and OS (HR=3.919, 95%CI: 1.918-8.009) (all P<0.05). However, the 8th edition of the AJCC N1 classification was not an independent prognostic factor to DFS (HR=1.360, 95%CI:0.767-2.412) or OS (HR=1.620, 95%CI:0.839-3.131) (both P>0.05) as revealed by multivariate analysis. Conclusions: The relapse risk and survival could be assessed effectively using the modified pathological N1 classification, which was defined and subcategorized based on the anatomical location of intrapulmonary metastatic lymph nodes for N1 NSCLC patients. The modified pathological N1 classification is superior to the 8th edition of the AJCC classification.

[Diagnostic value of platelet associated biomarkers in chronic periprosthetic joint infection]

Objective: To evaluate the diagnostic value of platelet count(PC),PC to mean platelet volume(MPV) ratio(PC/MPV) and plateletcrit(PCT) in chronic periprosthetic joint infection(PJI). Method: The medical records of 159 patients who underwent hip or knee revisions at Department of Joint Surgery,Affiliated Hospital of Qingdao University from August 2013 to June 2019 were retrospectively reviewed. There were 51 patients(26 knees and 25 hips) in the PJI group,which included 28 males and 23 females,aged (68.0±11.8)years (range:32 to 84 years)with a body mass index(BMI)of (26.1±3.6) kg/m².There were 116 patients(19 knees and 97 hips) in the aseptic loosening(AL) group,including 67 males and 49 females,aged (70.3±8.9)years(range:49 to 89 years)with a BMI of (25.0±3.6)kg/m².The plasma C-reactive protein(CRP),erythrocyte sedimentation rate(ESR),PC,MPV,PC/MPV and PCT levels of the two groups were recorded and analyzed. Receiver operating characteristic curve was used to calculate the sensitivity and specificity of each biomarker,expect for MPV,and the diagnostic value of each biomarker was compared according to the area under the curve(AUC).Independent-sample t test or Mann-Whitney U test were used for comparison between groups. Result: Compared with AL group,AJI group had significantly higher levels of CRP,ESR,PC,PC/MPV and PCT(all P<0.05),but lower level of MPV (P<0.05).The AUCs for CRP,ESR,PC,PC/MPV and PCT were 0.820, 0.829, 0.689, 0.668 and 0.676,respectively. Based on the Youden index,the optimal predictive cutoff for CRP was 11.12 mg/L,with a sensitivity of 74.4% and a specificity of 87.1%.The optimal predictive cutoff for ESR was 17.60 mm/1 h,with a sensitivity of 81.4% and a specificity of 75.3%.The optimal predictive cutoff for PC was 243.00×109/L,with a sensitivity of 60.6% and a specificity of 71.8%.The optimal predictive cutoff for PC/MPV was 24.95,the sensitivity was 58.1% and the specificity was 74.1%.And the optimal predictive cutoff for PCT was 0.24%,with a sensitivity of 69.8% and a specificity of 63.5%. Conclusion: PC,PC to MPV ratio and PCT were of limited value to diagnose PJI.

Discrete scattering and meta-arrest of locally resonant elastic wave metamaterials with a semi-infinite crack

Previous investigations on wave scattering and crack propagation in the discrete periodic structure are concentrated on the conditional mass–spring model, in which the internal mass is not included. In this work, elastic wave metamaterials with local resonators are studied to show the scattering of elastic waves by a semi-infinite crack and the arrest behaviour. The influences of internal mass–spring structure are analysed and the discrete Wiener–Hopf method is used to obtain the displacement solution. Numerical calculations are performed to show that the dynamic negative effective mass and band gaps can be observed owing to the local resonance of the internal mass. Therefore, the scattering of an elastic wave with a specific frequency by a semi-infinite crack can be avoided by tuning the structural parameters. Moreover, the energy release ratio which characterizes the splitting resistance is presented and the meta-arrest performance is found. It is expected that this study will increase understanding of how to control the scattering characteristics of elastic waves by a semi-infinite crack in locally resonant metamaterials and also help to improve their fracture resistance.

[Mesenchymal stem cells derived apoptotic extracellular vesicles attenuate pro-inflammatory macrophages induced by Porphyromonas gingivalis lipopolysaccharide]

Objective: To investigate whether bone marrow mesenchymal stem cells (BMMSCs) derived apoptotic extracellular vesicles (ApoEVs) could regulate the polarization of mouse macrophage cell line RAW264.7 and whether BMMSCs derived ApoEVs could attenuate pro-inflammatory condition of RAW264.7 induced by Porphyromonas gingivalis lipopolysaccharide (Pg-LPS), so as to provide experimental evidence and theoretical basis for using BMMSCs derived ApoEVs as a method to treat periodontitis. Methods: The Operetta CLS high-content analysis system was used to observe the time-dependent apoptosis process of BMMSCs. Besides, field emission scanning electron microscopy (FESEM), dynamic light scattering technology and streaming potential method were used to measure the surface characteristics of BMMSCs derived ApoEVs. The Operetta CLS high-content analysis system was used to observe the process of RAW264.7 phagocyting 5-carboxy-tetramethylrhodamine, succinimidyl ester (5-TAMRA-SE) labeled ApoEVs. Real-time quantitative PCR was used to detect the mRNA expression of arginase-1 (Arg-1). Cell immunofluorescence and Western blotting were used to detect the number of inducible nitric oxide synthase (iNOS)(+) macrophages and iNOS protein expression level in each experiment group. Enzyme linked immunosorbent assay was used to detect tumor necrosis factro-α (TNF-α) level in the Pg-LPS induced pro-inflammatory macrophage culture supernatant in each experiment group. Results: After treating with 0.5 μmol/L staurosporine for 12 hours, mouse BMMSCs underwent shrinking with obvious vesicles structure around. The FESEM showed the ApoEVs were in spherical shapes. The size range of ApoEVs was about 100-1 000 nm and the average Zeta potential was -16.6 mV. The Operetta CLS high-content analysis system showed RAW264.7 could phagocytose 5-TAMRA-SE labeled ApoEVs by pseudopodia. The relative mRNA expression of Arg-1 was significantly increased in RAW 264.7 after being treated with interleukin 4 (IL-4) and ApoEVs (261.97±15.91) compared to that with IL-4 alone (115.29±15.42) (P<0.01). Cell immunofluorescence showed that ApoEVs could reduce the number of iNOS(+) macrophages induced by Pg-LPS (39.33±4.70) comparing to those without ApoEVs (95.33±4.70) (P=0.007). In the meanwhile, ApoEVs could also down-regulate the iNOS protein level of macrophages induced by Pg-LPS (5.84±1.05) comparing to those without ApoEVs (14.91±3.87) (P<0.01). Besides, ApoEVs could also reduce the TNF-α secretion in the culture supernatant of pro-inflammatory macrophages induced by Pg-LPS [(21 899.71±409.73) ng/L] comparing to those without ApoEVs [(71 296.50±2 344.22) ng/L] (P=0.003). Conclusions: BMMSCs derived ApoEVs could regulate the polarization of macrophages and could also attenuate the pro-inflammatory condition of macrophages induced by Pg-LPS.

Electro-mechanical coupling diode of elastic wave in nonlinear piezoelectric metamaterials

In this investigation, the bandgaps and nonreciprocal transmission of the nonlinear piezoelectric phononic crystal and elastic wave metamaterial are studied. Analytical solutions for the wave motion equations with the electro-mechanical coupling are obtained. According to the continuous conditions, the stop bands and transmission coefficients of both fundamental wave and second harmonic are derived by the stiffness matrix method. Some particular examples are presented to show the nonreciprocal transmission of the nonlinear elastic waves. Additionally, nonlinear ultrasonic experiments are applied to verify the theoretical analyses and numerical simulations. This work is intended to be helpful in the design and fabrication of devices of the elastic wave diode with piezoelectric materials.

[Role and mechanism of low-dose lipopolysaccharide-treated human periodontal ligament stem cells on the expression of macrophage pro-inflammatory factors]

Objective: To investigate the effect of low dose lipopolysaccharide (LPS)-treated human periodontal ligament stem cells (HPDLSC) on the expression of macrophage pro-inflammatory factors and the mechanism involved. Methods: The primary HPDLSCs were obtained from healthy third molar periodontal ligament tissue. Phosphate buffer saline (PBS), 100 μg/L or 10 mg/L of LPS were used to treat HPDLSCs for 48 h, and their conditioned media were respectively co-cultured with THP-1-derived macrophages for 48 h. The corresponding experimental groups were PBS-treated HPDLSC-derived conditioned medium (CM-C) group, low dose LPS-treated HPDLSC-derived conditioned medium (CM-L) group, and high dose LPS-treated HPDLSC-derived conditioned medium (CM-H) group. Quantitative real-time PCR was performed to explore the mRNA expressions of macrophage interleukin (IL)-6, IL-8, IL-12, tumor necrosis factor-α (TNF-α) in the CM-C, CM-L and CM-H groups, and the expressions of nuclear factor (erythroid-derived 2)-like 2 (NRF2), glutamate-cysteine ligase catalytic subunit (GCLC), NAD(P)H quinone dehydrogenase 1 (NQO1) and heme oxygenase 1 (HO-1) in the CM-C and CM-L groups. Meanwhile, Western blotting was used to detect the change of nuclear and cytoplasmic NRF2 and the levels of GCLC and HO-1 in the CM-C and CM-L groups. The 2', 7'-dichlorofluorescein probe was adopted to detect the reactive oxygen species (ROS) levels of macrophages in the CM-C and CM-L groups and the data were characterized by the mean fluorescent intensity (MFI). Results: The mRNA expressions of macrophage pro-inflammatory factors IL-6, IL-8, IL-12 and TNF-α in the CM-H group (2.332±0.594, 3.601±0.639, 2.120±0.677 and 2.468±0.236) were significantly upregulated compared with those in the CM-C group (1.000±0.321, 1.000±0.151, 1.000±0.059 and 1.000±0.095) (P<0.05); while the relative mRNA levels of IL-6, IL-12 and TNF-α in the CM-L group (0.056±0.002, 0.215±0.024 and 0.567±0.071) were much lower than those in the CM-C group (1.000±0.209, 1.000±0.220 and 1.000±0.220) (P<0.05). At the mRNA level, the expression of NRF2 was significantly increased in the CM-L group (1.864±0.198) compared with that in the CM-C group (1.000±0.094) (P<0.05). At the protein level, the cytoplasmic NRF2 and nuclear NRF2 were increased in CM-L group (1.175±0.104 and 1.308±0.082) compared with those in the CM-C group (1.000±0.025 and 1.000±0.049) (P<0.05). Furthermore, the antioxidative genes, i.e. GCLC and NQO1, localized in NRF2 downstream, were significantly upregulated in the CM-L group (1.786±0.278 and 1.444±0.078) compared with the CM-C group (1.000±0.139 and 1.000±0.226) (P<0.05). The protein levels of GCLC and HO-1 were augmented in the CM-L group (1.159±0.036 and 1.412±0.075) in contrast with those in the CM-C group (1.000±0.050 and 1.000±0.013) (P<0.05). In addition, the MFI in the CM-L group (123 419±1 302) was significantly lower than that in the CM-C group (139 193±1 241) (P<0.05). Conclusions: Low-dose LPS-treated HPDLSCs could regulate oxidative stress response through activating the NRF2 signaling pathway of macrophages and further downregulating the expressions of macrophage pro-inflammatory factors.

Measurement of the Cosmic Ray Helium Energy Spectrum from 70 GeV to 80 TeV with the DAMPE Space Mission

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.

[Inflammatory periodontal stem cells mediate interleukin-1β secretion of macrophage by regulating macrophage endoplasmic reticulum stress]

Objective: To investigate the effect and mechanism of periodontal ligament stem cell (PDLSC) from inflammatory environment on the secretion of interleukin-1β (IL-1β) by macrophages. Methods: PDLSCs were pretreated with lipopolysaccharide (LPS) in order to simulate the inflammatory environment. Human monocyte cell line (THP-1) cells were treated with conditioned media collected from healthy and inflammatory PDLSCs respectively and divided into conditioned medium of health PDLSC (CM-H) group and conditioned medium of LPS-PDLSC (CM-LPS) group. After 24 h of co-culture, the condition media were abandoned and THP-1 cells were then cultured for another 24 h. The expression of IL-1β in THP-1 cells supernatant was detected by enzyme-linked immunosorbent assay (ELISA). Quantitative real time-PCR (qRT-PCR) was used to detect the expression of glucose regulated protein 78 (GRP78), activating transcription factor-6 (ATF6), inositol requiring enzyme 1 (IRE1), protein kinase R-like endoplasmic reticulum kinase (PERK), CCAAT enhancer binding protein homologous protein (CHOP), activating transcription factor-4 (ATF4) and X box binding protein 1 spliced (XBP1s), which were all related with endoplasmic reticulum stress (ERS), in THP-1 cells. The expressions of proteins GRP78 and CHOP were detected by Western blotting. Furthermore, THP-1 cells, which pretreated with ER inhibitor 4-phenylbutyrate (4-PBA) for intervention experiments were grouped by various concentrations of 4-PBA including groups 0 (control group), 1, 10 and 20 mmol/L and treated with condition medium of inflammatory PDLSC. ELISA was used to detect IL-1β expression and qRT-PCR to detect expression of ERS related genes. Results: ELISA results showed that the expression of IL-1β in THP-1 cells of group CM-LPS [(31.35±2.11) ng/L] was significantly higher than group CM-H [(8.19±1.51) ng/L] (t=12.60, P<0.01). qRT-PCR results showed that the relative expressions of GRP78, ATF6, IRE1, PERK, CHOP, ATF4 and XBP1s genes in THP-1 cells of group CM-LPS (1.782±0.070, 1.387±0.204, 1.404±0.119, 1.777±0.187, 1.325±0.156, 1.295±0.066 and 1.137±0.149, respectively) were significantly higher than those in group CM-H (P<0.05). In the 4-PBA intervention experiment, compared with group 0 mmol/L, the expressions of GRP78, IRE-1, ATF-6, PERK and CHOP were significantly lower in group 1, 10 and 20 mmol/L (P<0.05). Moreover, compared with control group [(31.23±1.98) ng/L], the expression of IL-1β in THP-1 cells were significantly lower in group 10 mmol/L [(21.20±0.37) ng/L] and group 20 mmol/L [(23.85±1.80) ng/L] (P<0.05) with ERS inhibited. Conclusions: PDLSC from inflammatory environment could promote IL-1β secretion of macrophages through upregulating macrophages ERS.

[Epidemiological research in the big data era: opportunities, challenges and prospectives]

Recent years with the rapid progress in high-throughput omics techniques, the accumulation of population cohorts and biobanks, great advances in internet and information technology, and the emerging tools for big data utilization, health care big data provide abundant data resources and broad research platforms for epidemiological research. We aimed to review the opportunities and challenges of epidemiological research in the era of big data, and explore the future development of epidemiology. Epidemiology should seize the opportunities, open up new directions, develop new methods, and promote the translation of research results into public health and clinical medicine, which will eventually realize the vision of "Healthy China".

Improving native human sperm freezing protection by using a modified vitrification method

Slow freezing is the most commonly used technique for the cryopreservation of spermatozoa in clinical practice. However, it has been shown to have a negative impact on sperm function and structure. Vitrification as a successful alternative method has been proved to have better protective effects on human embryos, but vitrification of spermatozoa is still subject to low recovery rates. In this study, a modified vitrification method for native spermatozoa was developed. A total of 28 semen samples were included; each sample was divided into three equal parts and assigned to fresh, slow freezing, and vitrification groups. Sperm vitality, motility, morphology, DNA integrity, and acrosome reaction were assessed for each of the groups. The results showed that vitrification achieves better results for several sperm protection parameters than slow freezing; vitrification achieves a higher recovery rate (P < 0.05), motility (P < 0.05), morphology (P < 0.05), and curve line velocity (P < 0.05) than slow freezing. Furthermore, DNA fragmentation was decreased (P < 0.05) and better acrosome protection (P < 0.05) was exhibited in the spermatozoa after vitrification. Principal component analysis of all sperm parameters revealed that the vitrification cluster was closer to the fresh cluster, indicating that spermatozoa are better preserved through vitrification. In conclusion, while both slow freezing and vitrification have negative effects on sperm function and structure, the vitrification protocol described here had a relatively better recovery rate (65.8%) and showed improved preservation of several sperm quality parameters compared with slow freezing.

Tunable mechanical diode of nonlinear elastic metamaterials induced by imperfect interface

In this investigation, the non-reciprocal transmission in a nonlinear elastic metamaterial with imperfect interfaces is studied. Based on the Bloch theorem and stiffness matrix method, the band gaps and transmission coefficients with imperfect interfaces are obtained for the fundamental and double frequency cases. The interfacial influences on the transmission behaviour are discussed for both the nonlinear phononic crystal and elastic metamaterial. Numerical results for the imperfect interface structure are compared with those for the perfect one. Furthermore, experiments are performed to support the theoretical analysis. The present research is expected to be helpful to design tunable devices with the non-reciprocal transmission and diode behaviour of the elastic metamaterial.

Vitamin A with L-ascorbic acid sodium salt improves the growth performance, immune function and antioxidant capacity of weaned pigs

Vitamin A is easily degraded by environmental factors. Therefore, it is very important to add antioxidants during Vitamin A production. In the past, ethoxyquin (EQ) was widely used, but recent studies have found that it has potential toxicity. Therefore, in this study, we evaluated the antioxidant activities of 4 antioxidants in vitro: EQ, butylated hydroxytoluene, α-tocopherol and L-ascorbic acid sodium salt (Vitamin C sodium). In vitro experiments showed that Vitamin C sodium had better antioxidant capacity. Then, we explored the effects of different antioxidant types of Vitamin A on the growth performance, immune function and antioxidant capacity of weaned pigs. In total, 288 weaned piglets with an initial mean BW of 8.34 ± 0.02 kg at 30 days old were randomly divided into three groups with four replicates and 24 piglets per replicate for 35 days of feeding. The experimental diets were as follows: i) basal diet without external Vitamin A (NC); ii) basal diet supplemented with 12000 IU/kg EQ Vitamin A and iii) basal diet supplemented with 12000 IU/kg Vitamin C sodium Vitamin A. On day 36, two pigs from each replicate were selected to collect serum samples. The in vivo results showed that pigs in the EQ Vitamin A and Vitamin C sodium Vitamin A groups had significantly higher final weight and average daily gain (P < 0.05). During the trial, the levels of IgG and glutathione peroxidase in the EQ Vitamin A and Vitamin C sodium Vitamin A groups were significantly higher than those in the NC group (P < 0.05), and the malondialdehyde content was significantly lower (P < 0.05). On the 36th day, the levels of IgA and total antioxidant capacity in the Vitamin C sodium Vitamin A group were significantly higher than those in the EQ Vitamin A and NC (P < 0.05) groups. Thus, Vitamin C sodium Vitamin A can significantly improve the growth performance, antioxidant capacity and immune function of weaned pigs. Meanwhile, Vitamin C sodium may replace EQ as an antioxidant additive for Vitamin A.

[Association between grip strength, rapid gait speed and cognition in people aged 50 and above in Shanghai during 2009-2010]

Objective: To investigate the association between grip strength, rapid gait speed and cognition in people aged 50 and above in Shanghai. Methods: Cross-sectional data was collected from the World Health Organization (WHO) study on global ageing and adult health (SAGE) wave 1 (2009-2010). A questionnaire survey was conducted among 8 643 participants aged 50 years old and above selected by using multistage random cluster sampling strategies in Shanghai. Factor analysis was applied to evaluate and generate cognitive function overall score.Association between grip strength, rapid gait speed and cognition was examined by a two-level hierarchical linear model. Results: A total of 8 175 participants were included in this study, who were (62.9±9.7) years old, including 3 782 (46.3%) males. The average grip strength and rapid gait speed of participants were (27.46±12.01) kg and (1.44±0.43) m/s respectively. The average scores of verbal recall (VR), verbal fluency (VF), forward digit span (FDS), backward digit span (BDS) and total cognitive scores were (5.72±0.09), (12.67±0.35), (6.84±0.10), (4.32±0.14) and (60.50±0.95) respectively. Grip strength was positively associated with VR, VF, FDS, BDS and overall cognition (standardized β=0.036, 0.079, 0.042, 0.046 and 0.043 respectively, P<0.05), and rapid gait speed was also positively associated with VR, VF and overall cognition (standardized β=0.040, 0.031, 0.039 respectively, P<0.05) after adjusted for age, sex, residence, education level, marital status, household income, co-morbidity of chronic conditions, BMI, drinking, smoking, fruits, vegetables intake and physical activities. Conclusion: Grip strength and rapid gait speed are both positively associated with cognitive function of people aged 50 and above, which would be indicators to evaluate their cognition.

Elastic wave cloak and invisibility of piezoelectric/piezomagnetic mechanical metamaterials

In this paper, a piezoelectric cloaking mechanism is proposed, which makes the enclosed piezomagnetic cylinder invisible to elastic shear horizontal (SH) waves. Based on the scattering cancellation technique, the piezoelectric cloaking mechanism and dynamic stress concentration factor (DSCF) is obtained by the plane wave expansion method. A nonlinear ray trajectory equation for SH waves is derived based on the nonlinear transformation. Furthermore, piezoelectric effects on both cloaking mechanism and dynamic stress concentration are analyzed. The numerical results show that the scattering cancellation can be attributed to the cloak density, and the piezoelectric property can enhance the object's invisibility. The piezoelectric cloaking design can be applied to reduce the DSCF in some frequency regions, which means that it can change the stress distribution. It means that piezoelectric scattering cancellation can enhance both the cloaking results and structural strength of the mechanical metamaterials. This study is expected to have significance for the development and design of elastic wave metamaterials.

Long noncoding RNA NNT-AS1 functions as an oncogene in breast cancer via repressing ZFP36 expression

Breast cancer is one of the most common cancers in women. This study focuses on the effects of Long non-coding RNAs (lncRNAs) NNT-AS1 on breast cancer cell growth and metastasis. Fifty-six pairs of breast cancer (BC) tissues and matched paracarcinoma tissues were obtained. The BC cell lines and normal human breast cell line were employed. NNT-AS1 in BC cells was knocked down by shRNA. Cell counting kit-8 assay (CCK-8), colony formation assay, cell cycle analysis, cell apoptosis analysis, cound healing assay, Transwell assay, cioinformatics analysis, Western blot analysis and Xenograft model were used. Quantitative real-time polymerase chain reaction (qRT-PCR) assay indicated that expression of NNT-AS1 was obviously upregulated in breast cancer tissues compared with adjacent tissues (n=56). Knockdown of NNT-AS1 could attenuate breast cancer cell viability, proliferation, invasion and migration, as well as promote cell apoptosis and induce cell cycle arrest at G0/G1 phase. ZFP36 was directly combined with NNT-AS1, and silencing of ZFP36 could rescue tumor suppression role by downregulating NNT-AS1 on cell proliferation and metastasis. Knockdown of NNT-AS1 could suppress cell growth and metastasis via interacting with ZFP36 in vivo. This study demonstrated that knockdown of NNT-AS1 had tumor-suppressive effect on breast cancer progression and metastasis via interacting with ZFP36 in vitro and in vivo, which provides a new insight into the treatment and prognosis evaluation of breast cancer.

[Oncologic outcomes of early stage cervical cancer performed operation by different laparoscopic surgical procedures: analysis of clinical data from mutiple centers]

Objective: To evaluate the oncologic outcomes of different laparoscopic radical hysterectomy. Methods: From January 2011 to December 2014, the laparoscopic operation cases of cervical cancer at stage Ⅰb1, Ⅰb2, Ⅱa1 and Ⅱa2, including the histologic subtypes of squamous-cell carcinoma, adenocarcinoma and adenosquamous carcinoma, were collected in five clinical centers. The data were divided into two groups according to the surgical procedures, that is, modified laparoscopic-vaginal radical hysterectomy (mLVRH) and total laparoscopic radical hysterectomy (TLRH). The overall survival rate (OS), disease-free survival rate (DFS) at 5 years were retrospectively analyzed in this study. Results: There were 674 cases in total, including 377 cases of mLVRH, 297 cases of TLRH. (1) The OS at 5 years: the mLVRH was 96.1% and the TLRH was 92.0%, and the mLVRH was higher than that of TLRH （P=0.010）. Stratify analysis， including stage of disease （Ⅰb1 and Ⅱa1）， histologic subtypes （squamous-cell carcinoma, adenocarcinoma）， lymph node metastasis， revealed that, ① Stage of disease: in stage Ⅰb1, the OS at five years of mLVRH was higher than that in TLRH group （98.6% vs 93.6%, P=0.012）. In stage Ⅱa1, there was significant difference between the two groups, the OS at five years of mLVRH and TLRH were 93.6% and 77.6% （P=0.007）. ② Histologic subtypes: for the OS at five years of squamous-cell carcinoma, mLVRH and TLRH were 96.1% and 92.3%, and there was significant difference （P=0.046）； for adenocarcinoma, the OS at five years were 91.0% and 88.6%， and there was no difference between two groups （P=0.230）. ③ Lymph node metastasis： the mLVRH and TLRH with lymph node metastasis, the OS at five years were 98.6% and 96.4%; the mLVRH and TLRH without lymph node metastasis, the OS at five years were 89.3% and 80.8%. There were no significant differences between the two groups,respectively (P=0.156， P=0.093）. (2) The DFS at 5 years: there was no significant difference between mLVRH and TLRH (94.1% vs 90.9%, P=0.220). Stratify analysis for stage of disease, the mLVRH group was higher than that in the TLRH group in stage Ⅰb1 (97.0% vs 92.8%, P=0.039). However, for stage Ⅱa1, there was no significant difference between mLVRH and TLRH group （88.2% vs 75.8%, P=0.074）. Conclusions: The results of this retrospective study indicated that different laparoscopy surgical procedures had diverse oncologic outcomes. The OS at 5 years of the mLVRH is superior to the TLRH. The DFS at 5 years in Ⅰb1 stage, the mLVRH is higher than the TLRH. Therefore, the modified laparoscopy is still an alternative surgery for early cervical cancer patients when following the principle of no-tumor-exposure.

[Correlation analysis of the prognostic value of serum hyaluronic acid for breast cancer patients]

Objective: To explore the correlation between preoperative serum hyaluronic acid (HA) level and prognosis of breast cancer patients. Methods: The 98 patients with breast cancer who underwent surgical treatment in the Oncology Department of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine from January 2004 to November 2014 in a historical cohort were included, aged (52.5±9.4) years.The preoperative serum HA contents of the patients were detected. According to the median of 53.7 μg/L, the patients were divided into high and low groups with 49 patients in each group.The χ² test was used to analyze the correlation between the serum HA content and the general clinical data of the patients, and the Kaplan-Meier method, Log-rank test and multivariate Cox regression model wereusedto analyze the correlation between HA content and patients' survival. Results: The percentages of patients with high HA levels in menopause and non-menopause patientswere 55.7% and 40.5%, respectively; in progesterone receptor (PR) positive and negative patients were 54.1% and 43.2%, respectively; in estrogen receptor (ER) positive and negative patients were 45.7% and 60.7%, respectively; in Ki-67 positive and negative patients were 55.6% and 43.2%, respectively; in the tumor size stage TⅠ, TⅡ, TⅢ, and TⅣ patients were 50.0%, 41.7%, 72.7%, and 1/1, respectively; in lymph node metastasis and non-metastasispatients were 45.7% and 53.8%, respectively. There was no significant correlation between the level of HA and the menopausal status, the expressions of PR, ER and Ki-67, tumor size, and lymph node metastasis in breast cancer patients (χ²=2.128, 1.086, 1.800, 1.485, 4.273, 0.656, P>0.05). Patients with high HA levels accounted for 30.9% of patients aged 52 years or less and 74.4% of patients older than 52 years (χ²=18.274, P=0.000); 43.4% of patients with early TNM and 72.7% of patients with advanced TNM (χ²=5.861, P=0.015); 45.2% of patients without distant metastasis and 78.6% of patients with distant metastasis (χ²=5.333, P=0.023); 38.1% of Her-2 negative patients and 58.9% of Her-2 positive patients(χ²=4.167, P=0.041); and the median survival of patients with high HA levels was 70 months, which was shorter than 83 months for patients with low HA levels (χ²=6.799, P=0.007). Therefore, ahigh HA content predicts an older age, a later tumor stage, higher risk of distant metastasis, positive expression of Her-2 and shorter survival. Multivariate Cox regression model analysis suggested that high levels of serum HA may be a risk factor for patients' survival, with HR (95%CI) value of 9.98 (1.16-85.88) and P value of 0.036. Conclusion: The high level of preoperative serum HA has a certain correlation with the poor prognosis of breast cancer patients.

[Discussion on the curative effect and mechanisms of berberine in rats with non-alcoholic fatty liver]

Objective: To observe the curative effects of berberine in rats with high-fat diet induced non-alcoholic fatty liver and to further explore its possible mechanism. Methods: Twenty-six Sprague-Dawley rats (120-160 g) were randomly divided into 3 groups: control group (n = 8), model group (n = 10) and treatment group (n = 8). Rats in the control group were fed with regular diet, and the model group and the treatment group were fed a high-fat diet. At the 12th week, two rats in the in the model group were sacrificed to verify whether model was successful established. Subsequently, treatment group rats were given a gavage of berberine at a dose of 150 mg·kg(-1)·d(-1) for 4 weeks, and the control and the model group rats were given the same dose of normal saline. Rats were sacrificed at week 16th. HE staining was used to observe the changes in the intestinal mucosa of rats. Sudan black B staining was used to observe the fatty changes in liver. Immunohistochemical staining was used to observe the expression level of occludin protein in the intestinal epithelium. A real-time 16S rDNA PCR method was used to measure the number of escherichia coli, bacteroides and faecalibacterium prausnitzii in the feces of rats. Results: Model group had a higher serum levels of endotoxin (0.288 ± 0.045) and tumor necrosis factor (TNF)-α (1.07 ± 0.11) than the control group (0.192 ± 0.049, 0.94 ± 0.07) (P < 0.05). Berberine intervention had significantly reduced endotoxin (0.213 ± 0.025) and TNF-α level (0.93 ± 0.07) (P < 0.05). The expression level of occludin protein was significantly lower in the intestinal mucosa of model group than that of control group (0.166 ± 0.014), and berberine had promoted the expression of occludin protein in intestinal mucosa (0.055 ± 0.009), but the difference was not statistically significant (P > 0.05). At the same time, compared with the model group (7.29 ± 0.47), the number of bacteroidetes in the control group (9.49 ± 0.59) was decreased, while the number of bacteroidetes in the treatment group was increased (9.77 ± 0.87). The number of escherichia coli (6.92 ± 0.77) and faecalibacterium prausnitzii (8.70 ± 0.62) in the model group were increased than control group (5.42 ± 0.63, 9.49 ± 0.59), while the number of escherichia coli (6.34 ± 0.71) and faecalibacterium prausnitzii (9.77 ± 0.87) (P < 0.05) was reduced with the intervention of berberine. Conclusion: Berberine could effectively protect the intestinal barrier function in rats with NAFLD and the possible mechanism of action behind it may be the regulation of intestinal flora.

[Challenges and factors that influencing causal inference and interpretation, based on Mendelian randomization studies]

Genetic variation is used as instrumental variable to investigate the causal relationship between exposure and outcome, which can avoid issues of confounding and reserve causation regarding Mendelian randomization studies. However, the instrumental variables in Mendelian randomization studies must satisfy three core assumptions-the relevance assumption, the independence assumption, and the exclusion restriction assumption. In addition to the plausibility of core assumptions, the application of Mendelian randomization studies in causal inference is also subject to other limitations. Findings from the Mendelian randomization studies should be interpreted in the context of existing evidence from other sources. In this article we provide an overview of the assumptions, limitations, and interpretation on causal inference that related to Mendelian randomization studies that can be applied in studies of the same kind.

Active control on topological immunity of elastic wave metamaterials

The topology concept in the condensed physics and acoustics is introduced into the elastic wave metamaterial plate, which can show the topological property of the flexural wave. The elastic wave metamaterial plate consists of the hexagonal array which is connected by the piezoelectric shunting circuits. The Dirac point is found by adjusting the size of the unit cell and numerical simulations are illustrated to show the topological immunity. Then the closing and breaking of the Dirac point can be generated by the negative capacitance circuits. These investigations denote that the topological immunity can be achieved for flexural wave in mechanical metamaterial plate. The experiments with the active control action are finally carried out to support the numerical design.

[Minimal residual disease in adults with Philadelphia chromosome negative acute lymphoblastic leukemia in high-risk]

目的

探讨高危Ph阴性急性淋巴细胞白血病（Ph⁻ALL）中微小残留病（MRD）对预后和治疗策略的影响。

方法

回顾性分析2008年1月1日至2017年12月31日收治的初治成人高危Ph⁻ALL并获得完全缓解（CR）患者的临床资料，通过Cox回归模型和Landmark分析，寻找预后相关因素。

结果

177例患者纳入研究，其中男性99例（56%），中位年龄40（16~65）岁，95例（54%）在第1次完全缓解（CR₁）后接受异基因造血干细胞移植（移植组）。多因素分析显示，巩固治疗1个疗程后MRD阴性（HR=0.52，95%CI 0.30~0.89，P=0.017）、诱导化疗4周达到CR（HR=0.43，95%CI 0.24~0.79，P=0.006）是影响患者无病生存（DFS）的有利因素，CR₁移植是影响患者DFS（HR=0.13，95%CI 0.08~0.22，P<0.001）和总生存（OS）（HR=0.24，95%CI 0.15~0.41，P<0.001）的共同有利因素。121例患者进入Landmark分析，在巩固治疗1个疗程后MRD阴性的85例患者中进行多因素分析显示，巩固治疗3个疗程后MRD阴性是影响患者DFS（HR=0.18，95%CI 0.05~0.64，P=0.008）和OS（HR=0.14，95%CI 0.04~0.50，P=0.003）的有利因素。在巩固治疗1个疗程和3个疗程后MRD均阴性的患者中，移植组患者3年DFS率有高于化疗组的趋势（75.2%对51.3%，P=0.082），但3年OS率相近（72.7%对68.7%，P=0.992）。巩固治疗1个疗程和3个疗程后MRD至少1次阳性的患者中，移植组的3年DFS率（64.8%对33.3%，P=0.006）和3年OS率（77.0%对33.3%，P=0.028）均显著高于化疗组，与这两个时间点MRD均阴性的移植患者的预后差异无统计学意义（P>0.05）。

结论

在高危成人Ph⁻ALL患者中，巩固治疗1个疗程后MRD阴性是预后良好的独立影响因素。巩固治疗1个疗程和3个疗程MRD均阴性的患者，接受移植或化疗的生存率相似。移植显著改善了巩固治疗1个疗程和3个疗程后MRD至少一次阳性患者的预后。

[Clinicopathological and molecular features of pulmonary enteric adenocarcinoma]

Objective: To investigate the clinicopathological and molecular characteristics of pulmonary enteric adenocarcinoma (PEAC). Methods: The clinical and pathological data of 19 cases of PEAC in the Affiliated Cancer Hospital of Zhengzhou University were retrospectively collected from 2015 to 2019. Immunohistochemistry (IHC) was used to detect the relevant immunophenotypes, amplification refractory mutation system (ARMS) and fluorescence in situ hybridization (FISH) were used to detect the expression of EGFR, KRAS and ALK genes. The patients were followed up, and the relevant literature was reviewed and analyzed. Results: There were 19 cases, including 10 males and 9 females, with a mean age of 58 years (range 33-71 years). Microscopically, the tumors showed moderately to highly differentiated adenoid and/or papillary growth patterns. The tumor cells were highly columnar and sometimes showed pseudostratification. Inflammatory necrosis and scattered nuclear fragmentation were seen in some glandular lumens. IHC showed variable expression of CK7 (19/19), TTF1 (8/19), Napsin A (6/19), villin (17/19), CK20 (16/19) and CDX2 (10/19). Molecular testing showed KRAS mutation in nine cases (9/19), EGFR mutation in one case (1/19), and positive ALK split signal in one case (1/19). In the literature, the reported mutation rate of KRAS in PEAC was much higher than that of EGFR and ALK. All 19 cases underwent surgical resection and 11 cases were subjected to chemotherapy or radiotherapy. Conclusions: PEAC is a rare variant of invasive pulmonary adenocarcinoma, and has similar histological and cytological features to that of colorectal adenocarcinoma. However, detailed medical history, histologic heterogeneity, an IHC combination of CK7(+)/villin(+) and high KRAS mutation rate are the key points of diagnosis. The prognosis needs long-term follow-up and big data statistics.

Polymorphisms of 19 Autosomal STR Loci in Sichuan Han Population and Their Forensic Application

Objective To investigate the allele distribution, population genetics parameters and genetic analysis of neighboring populations of 19 autosomal STR loci in Sichuan Han population, and to evaluate their forensic application value. Methods The Goldeneye?? DNA ID system 20A was used to perform multiplex PCR amplification and allelic gene typing of 19 STR loci in 1 201 unrelated Han individuals from Sichuan Province. Allele frequencies and population genetics parameters were calculated. The Nei's genetic distances between Sichuan Han population and 12 previously reported populations were analyzed. Multidimensional scaling and principal component analysis were carried out and phylogenetic trees were also constructed. Results The heterozygosity of 19 STR loci ranged from 0.617 0 to 0.915 1, their discrimination power ranged from 0.777 4 to 0.986 5, matching probability ranged from 0.013 5 to 0.222 6, polymorphism information content ranged from 0.546 4 to 0.910 5, probability of exclusion ranged from 0.311 8 to 0.826 3 （triplet） and from 0.197 9 to 0.712 1 （biplet）, and no significant deviations from Hardy-Weinberg equilibrium were observed. Based on the results of multidimensional scaling, principal component analysis and phylogenetic trees of the genetic distances between Sichuan Han population and the other 12 populations, Sichuan Han population was closest to Hubei Han population and was farthest to Xinjiang Uygur population. Conclusion The 19 autosomal STR loci showed a high polymorphism and discriminating ability in Sichuan Han population, which can provide a data foundation for personal identification, paternity test and population genetics study.

Source, migration and toxicology of microplastics in soil

Microplastics are emerging contaminants and their presence in water and soil ecosystems has recently drawn considerable attention because they pose a great threat to entire ecosystems. Recent researches have focused on the detection, occurrence, characterization, and toxicology of microplastics in marine and freshwater ecosystems; however, our understanding of the ecological effects of microplastics in soil ecosystems is still limited compared with that in aquatic ecosystems. Here, we have compiled literature, studying the sources, migration of microplastics in soil, negative impacts on soil health and function, trophic transfer in food chains, and the corresponding adverse effects on soil organisms in order to address the potential ecological and human health risks caused by microplastics in soil. This review aims to address gaps in knowledge, shed light on the ecological effects of microplastics in soil, and propose future studies on microplastic pollution and the resultant soil ecotoxicity. Furthermore, this review is focused on limiting microplastics in soil and establishing management and remediation measures to mitigate the risks posed by microplastic pollution.

[The consideration about study design and implementation of vaccine clinic trials]

The safety of prophylactic vaccine is one of the key points both in clinical trials and evaluation. Based on the review practice of vaccine registration clinical trials in recent years, we puts forward a series of thoughts and suggestions on the common problems of safety study on vaccine, including the hypothesis of safety study, the consideration of inclusion/exclusion criteria and suspension/termination criteria for study; the routine requirements of safety study and some special issue such as medical laboratory test index, vaccine virus shedding and safety of adjuvant, and further clarifies the requirements of safety observation on sequential enrollment; also emphasized the scientific judgment of causality and the quality of safety monitoring. It can be used for reference by vaccine researchers and to explore appropriate solutions to promote vaccine research & development and risk control in China.

[The consideration about safety data analysis and expression in instructions of vaccine clinic trials]

The safety of prophylactic vaccine is one of the key points both in clinical trials and evaluation. Based on the review practice of vaccine registration clinical trials in recent years, we summarized the common problems in safety analysis and report and accordingly puts forward a series of thoughts and suggestions, including discussing the role of statistics in safety analysis, putting forward the framework of safety analysis and report involved analysis content, analysis index and analysis dimension, in which attention is paid to the severity analysis; emphasizing the initiative analysis on risk signal and encouraging the evidence-based initiative safety evaluation. At the same time, this paper discusses the basic principles of the presentation of safety data in the package inserts, as well as the comprehensive consideration of the safety data of each phase of the trial and different subjects. It can be used for reference by sponsor to promote vaccine clinical research and evaluation in China.