Risk factors for placenta accreta spectrum without prior cesarean section: A case-control study in China.

OBJECTIVE: To identify the risk factors for placenta accreta spectrum (PAS) disorders in women without prior cesarean section (CS). METHODS: This retrospective case-control study investigated patients without prior CS who gave birth at Peking University Third Hospital between January 1, 2015 and December 31, 2021. Patients diagnosed with PAS according to the clinical diagnostic criteria of the 2019 International Federation of Gynecology and Obstetrics (FIGO) classification were included as the study group. Patients were matched as the control group according to delivery date and placenta previa, in a 1:2 allocation ratio. Maternal characteristics were compared between the two groups. RESULTS: The study included 348 patients in the study group and 696 in the control group. The multivariate analysis showed that the independent risk factors of PAS consisted of operative hysteroscopy (once: adjusted odds ratio [aOR] 2.38, 95% CI 1.28-4.24, P = 0.006; twice or more: aOR 5.43, 95% CI 1.04-28.32, P = 0.045), uterine curettage (once: aOR 2.54, 95% CI 1.80-3.58, P < 0.001; twice: aOR 3.01, 95% CI 1.81-5.02, P < 0.001; three or more times: aOR 9.18, 95% CI 4.64-18.18, P < 0.001), multifetal pregnancy (aOR 5.64, 95% CI 3.01-10.57, P < 0.001), adenomyosis (aOR 2.77, 95% CI 1.23-6.22, P = 0.014), in vitro fertilization (aOR 1.51, 95% CI 1.04-2.20, P = 0.030) and pre-eclampsia (aOR 2.72, 95% CI 1.36-5.45, P = 0.005), and the independent protective factor was being multiparous (aOR 0.37, 95% CI 0.25-0.54, P < 0.001). CONCLUSION: After controlling the effect of placenta previa, we found that patients with PAS without prior CS had unique maternal characteristics. Classification and quantification of the intrauterine surgeries they have undergone is essential for identifying high-risk patients. Early identification of high-risk groups by risk factors has the potential to improve the prognosis considerably.

[A multicenter clinical study on the treatment of lateral epicondylitis of humerus by manipulation].

OBJECTIVE: To investigate clinical effect of tendons pulling,poking and kneading for the treatment of external humeral epicondylitis. METHODS: From January 2018 to December 2021,a multicenter randomized controlled study was performed to collect 192 patients with external humeral epicondylitis in Wangjing Hospital,Beijing Dianli Hospital,and Beijing Fengsheng Osteotraumatology Hospital,respectively,and they were divided into treatment group and control group by random number table method. There were 96 patients in treatment group,including 36 males and 60 females,aged from 28 to 60 years old with an average of (41.20±5.50) years old;the course of disease ranged from 1 to 14 days with an average of (5.24±1.35) days;they were treated once every other day for 2 weeks. There were 96 patients in control group ,including 33 males and 63 females,aged from 26 to 60 years old with an average of (43.35±7.75) years old;the course of disease ranged from 1 to 14 days with an average of (5.86±1.48) days;they were treated with topical voltaalin combined with elbow joint fixation for 2 weeks. Visual analogue scale (VAS) and Hospital for Surgery Scoring System (HSS) elbow pronation and supination angles,wrist metacarpal flexion and dorsal extension angles,elbow tenderness between two groups were compared before treatment and at 1,3,5,7,11 and 13 days after treatment;Hospital for Surgery Scoring System 2 (HSS2) was compared before treatment and the final treatment. RESULTS: All patients were followed up for 10 to 14 days with an average of (12±1.6) days. VAS between treatment group and control group before treatment were 6.83±1.36 and 6.79±1.58,respectively,and decreased to 1.49±1.09 and 2.11±1.81 after the final treatment. VAS of treatment group were significantly lower than those of control group at 1,3,5,7,9,11 and 13 days after treatment (P<0.05). HSS between two groups were 61.73±11.00 and 36.47±12.45 before treatment,respectively,and increased to 94.42±5.9 and 91.44±9.11 at the final treatment. HSS of treatment group were significantly higher than those of control group at 1,3,5,7,9,11 and 13 days after treatment (P<0.05). On the 5th day after treatment,the external and internal rotation angles of elbow in treatment group were (66.41±12.69) ° and (66.35±13.54) °,while those in control group were (62.08±16.03) ° and (61.77±16.35) °. On the 7th day after treatment,the external and internal rotation angles of elbow were (69.79±12.64) ° and (70.02±13.55) ° in treatment group,and (65.28±15.86) ° and (65.09±16.67) ° in control group. Elbow joint motion in treatment group was higher than that in control group (P<0.05). On the 5th day after treatment,angles of wrist dorsiflexion and palm flexion were (39.43±15.94) ° and (46.68±11.10) ° in treatment group,and (38.51±18.49) ° and (44.27±13.58) ° in control group. On the 7th day after treatment,angles of wrist dorsiflexion and palm flexion were (42.52±16.50) ° and (49.23±10.96) ° in treatment group,and (41.18±20.09) ° and (46.64±14.63) ° in control group. The motion of wrist joint in treatment group was higher than that in control group (P<0.05). On the 13th day after treatment,HSS2 in treatment group 93.61±6.32 were higher than those in control group 92.06±7.94(P<0.05). There was no significant difference in elbow tenderness between two groups at each time point (P>0.05). CONCLUSION: Voltaren external treatment combined with elbow fixation and tendons pulling,poking and kneading could effectively improve symptoms of external humeral epicondylitis. Compared with voltaren external treatment,tendons pulling,poking and kneading has advantages of longer analgesic time and better elbow function recovery.

Degradation of atrazine by electro-peroxone enhanced by Fe and N co-doped carbon nanotubes with simultaneous catalysis of H2O2 and O3.

Fe and N co-doped carbon nanotubes (Fe-N-CNT) was synthesized and attempted as efficient heterogeneous catalysts for simultaneous catalysis of H2O2 and O3 to improve electro-peroxone (Fe-N-CNT/EP) process efficiency for atrazine (ATZ) degradation. The removal and mineralization of ATZ was significantly enhanced, obtaining the degradation rate constant (k) by Fe-N-CNT/EP (0.23 min-1) about two times that of EP (0.12 min-1) owing to the formation of Fe0 and Fe-N coordination in Fe-N-CNT catalyst for co-catalysis of H2O2 and O3. The important factors such as applied current and ozone concentration were investigated, demonstrating that the optimized performance could be achieved at current of 30 mA and ozone concentration of 55 mg L-1. The oxidation capacity of Fe-N-CNT/EP maintained stably under wide pH range of 3∼7, obtaining the degradation rate constant 1.23-1.92 times that of EP and overcoming the defect of EP at acidic and neutral conditions. Capture experiments and electron paramagnetic resonance (EPR) experiments verified that .OH, generated by accelerating decomposition of H2O2/O3 and peroxone reaction, was the dominant active specie in Fe-N-CNT/EP. Besides, Fe-N-CNT showed high catalytic activity and good stability during six cycles. This work provides an efficient activator for enhanced EP process, exhibiting a promising prospect for water and wastewater purification.

[Study on the mechanism of haitongpi prescription extract ointment in the treatment of knee osteoarthritis based on transcriptome].

OBJECTIVE: To explore the mechanism of Haitongpi Prescription extract in the treatment of knee osteoarthritis based on transcriptome. METHODS: Total of 12 SPF grade rats were divided into control group(group C), model group(group M), and Haitongpi prescription group(group HP). The knee osteoarthritis rat model was established using the Panicker method for group M and group HP, and group HP was intervened by local topical application of Haitongpi Prescription extract for 4 weeks. Total RNA from mouse knee cartilage was extracted and three sets of differential genes were obtained through sequencing.Differential genes were prediction and analysis through GO function and KEGG pathway enrichment analysis. RESULTS: A total of 109 differentially expressed genes were identified in Group C versus Group M, while 118 differentially expressed genes were identified in Group M versus Group HP, resulting in a total of 28 genes. GO functional enrichment analysis showed that the mechanism of HP extract in treating knee osteoarthritis mainly involved immunoglobulin mediated immune response, immunoglobulin complexes, and antigen binding; KEGG pathway enrichment analysis showed correlation with tumor necrosis factor (TNF) signaling pathway, interleukin 17(IL-17) signaling pathway, and estrogen signaling pathway. CONCLUSION: HP extract can exert therapeutic effects on knee osteoarthritis through mechanisms such as immunoglobulin mediated immune response, immunoglobulin complexes, and antigen binding, as well as signaling pathways such as TNF signaling pathway, IL-17 signaling pathway, and estrogen signaling pathway.

Chitosan coating enriched with biosynthetic CuO NPs: Effects on postharvest decay and quality of mango fruit.

A chitosan-based nanocomposite film (CSC) was developed by mixing chitosan (CS, 2 %, v/v) and copper oxide nanoparticles (CuO NPs, 500 µg∙mL-1) synthesized using Alpinia officinarum extract for the safe storage of mango fruit. The effects of CuO NPs on the morphological, mechanical, thermal, physical and antifungal properties of the CS films and postharvest quality of mango fruit were determined. Scanning electron microscopy (SEM) analysis confirmed that CuO NPs were uniformly dispersed into the CS matrix. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) profiles showed that intermolecular H-bondings occurred between CS and CuO NPs, accompanied by decreased crystallinity and increased amorphous structure. In comparison to the pure CS film, addition of CuO NPs obviously improved the morphological, mechanical, thermal, physical and antifungal properties of CSC film. CSC coating treatment obviously delayed the fruit decay and yellowing, as well as reduced losses of weight and firmness of mango (Mangifera indica L.) fruit during the storage, when compared with the control and CS coating treatment. Meanwhile, it significantly decreased the respiration rate and ethylene generation and maintained high level of ascorbic acid (AsA), titratable acid (TA) and soluble sugar content (SSC) of the fruit during the storage. Notably, Cu presented in the CSC film was restrained to the peel, indicating that the CSC coated mango fruit had good edible safety. Principal component analysis (PCA) confirmed that CSC coating played a positive role in mango preservation. Therefore, CSC coating can be considered a potential application for successfully controlling of postharvest disease and prolonging the shelf life for mango fruit.

Traditional Chinese Medicine formula Bu-Shen-Huo-Xue-Fang (BSHXF) protects nucleus pulposus cells against the inflammatory and oxidative stress-induced degenerative changes.

Degeneration of the intervertebral disc is primarily caused by the loss of nucleus pulposus cells (NPCs) and extracellular matrix (ECM) (IDD). Bu-Shen-Huo-Xue-Fang (BSHXF), a traditional Chinese medicine decoction, has been used to treat IDD in clinical; nevertheless, the active components and underlying molecular mechanisms remain unknown. BSHXF improved IL-1ß and H2O2 stimulation-induced injuries on NPCs by promoting cell viability, increasing ECM deposition, inhibiting cell senescence, and decreasing the levels of inflammatory factors. The active ingredients in BSHXF were identified by LC-MS/MS analysis; three active ingredients from the principal drugs, Aucubin, Tanshinol, and Tanshinone II A promoted NPC viability; and Aucubin and Tanshinol promoted NPC viability more. Aucubin and Tanshinol, respectively, improved H2O2 stimulation-induced injuries on NPCs by promoting cell viability, increasing ECM deposition, inhibiting cell senescence, and decreasing the levels of inflammatory factors. The activator of NF-κB and Wnt signaling pathways attenuated Aucubin and Tanshinol's protective effects by promoting ECM degradation and NPC senescence. Aucubin, Tanshinol, and Tanshinone II A were identified as the most potent compounds in BSHXF protection against degenerative changes in NPCs. The NF-κB and Wnt signaling pathways might be involved in the protective effects of Aucubin and Tanshinol against H2O2-induced degenerative changes.

Mechanism of icariin for the treatment of osteoarthritis based on network pharmacology and molecular docking method.

BACKGROUND: Icarin's mechanism of action in osteoarthritis (OA) was explored using network pharmacology and the GEO database, and then further validated using molecular docking. METHODS: GEO database using network pharmacology identified differential genes in OA based on Icariin's possible targets predicted by pharmmapper database. Combining the differentially expressed genes in OA with the OA-related targets, the overlapping targets were removed. In order to determine what Icariin's core targets are for treating OA, PPI network analysis was performed using OA-related targets and possible Icariin targets. Furthermore, molecular docking was used to verify the chemical's binding to the targets. Final steps included Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of genes and genomes (KEGG) pathway enrichment analysis. Cytoscape was used to construct a network of compound-target-pathway-disease. RESULTS: Protein-protein interactions between overlapping targets revealed 151 intersection targets based on a network analysis. The top ten targets with the highest enrichment scores were SRC, MAPK1, HSP90AA1, AKT1, PTPN11, ESR1, EGFR, RhoA, JAK2, and MAPK14. KEGG enrichment analysis showed that the pathways at which Icariin intervention occurs include the OA including FOXO signaling pathway, and estrogen signaling pathway. The GO analysis result showed that various biologic processes such as proteolysis, angiogenesis, innate immune response, and positive regulation of inflammatory response were involved in treatment. Molecular docking analysis confirmed that Icariin could bind well to the targets through intermolecular forces. CONCLUSION: With its multi-targeting and multi-pathway characteristics, Icariin is a promising candidate drug for treating OA.

Research progress and hot spot analysis related to oxidative stress and osteoarthritis: a bibliometric analysis.

BACKGROUND: Osteoarthritis, a common degenerative osteochondral disease, has a close relationship between its mechanism of occurrence and oxidative stress. However, there are relatively few relevant studies in this field, and a more mature research system has not yet been formed. METHODS: By searching the Web of Science (WOS) database, we obtained 1 412 publications in the field of osteoarthritis and oxidative stress. The search results were then analyzed bibliometrically using Citespace and VOSviewer, including a study of publication trends in the field, analysis of core authors, analysis of countries and institutions with high contributions, analysis of core journals, and to identify research trends and hot spots in the field, we performed keyword clustering. RESULTS: We collected 1 412 publications on the field of osteoarthritis and oxidative stress from 1998-2022. By analyzing the publication trends in the field, we noted an exponential increase in the number of publications per year since 2014. We then identified the core authors in the field (Blanco, Francisco J., Loeser, Richard F., Vaamonde-garcia, et.al) as well as the countries (China, USA, Italy et.al) and institutions (Xi An Jiao Tong Univ, Wenzhou Med Univ, Zhejiang Univ et.al). The OSTEOARTHRITIS AND CARTILAGE and INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES contain a large number of research papers in this field, and through keyword co-occurrence analysis, we counted 3 227 keywords appearing in the field of osteoarthritis and oxidative stress. These keywords were clustered into 9 groups, representing 9 different research hotspots. CONCLUSIONS: Research in the field of osteoarthritis and oxidative stress has been developing since 1998 and is now maturing, but there is an urgent need to strengthen international academic exchanges and discuss the future focus of research development in the field of osteoarthritis and oxidative stress.

A liposome-based aptasensor integrated with competitive reaction enabling portable and electrochemical detection of Aß oligomer.

Aggregation of ß-amyloid (Aß) were considered as a typical pathological feature of Alzheimer's disease (AD). Extensive studies have verified that soluble Aß oligomers (AßO) were more toxic to neurons than plaques. Herein, in this work, a glucose entrapped liposome-based portable aptasensor was fabricated for recognizing and interacting with AßO by specific aptamer on liposome (G-Lip-Apt). Then, a single strand DNA, designed to be partially complementary to AßO aptamer, was modified on amino-functionalized Fe3O4@SiO2 to obtain a magnetic nanocomposite (Fe3O4@SiO2/NH2-DNA). In the presence of AßO, the specific recognition between AßO and its aptamer on G-Lip-Apt made AßO bounded with G-Lip-Apt. With subsequent introduction of Fe3O4@SiO2/NH2-DNA, the unreacted G-Lip-Apt was further linked with Fe3O4@SiO2/NH2-DNA by double stranded complementary pairing interaction. Along with the addition of TritonX-100 into the formed G-Lip-Apt/Fe3O4@SiO2/NH2-DNA complex, the encapsulated glucose was released from liposome and then measured by a personal glucose meter (PGM). Good linear correlation was acquired over concentration of 5.0-1000 nM and the limit of detection (LOD) was calculated to be 2.27 nM for AßO. The developed portable electrochemical strategy integrated magnetic separation, competitive reaction and point of care test (POCT) to achieve high sensitivity, selectivity and accuracy, therefore enabled it successfully applied to the analysis of AßO in the hippocampus and cortex of APP/PS1 transgenic AD mice.

Degradation of carbamazepine over MOFs derived FeMn@C bimetallic heterogeneous electro-Fenton catalyst.

A highly efficient heterogeneous electro-Fenton (Hetero-EF) catalyst with core-shell structure was successfully prepared by calcination of Mn-doped Mil-53 (Fe) precursor at high temperature. FeMn@C-800/2 prepared at pyrolysis temperature of 800 °C and Fe:Mn molar doping ratio of 2:1 showed the best catalytic performance for the degradation of carbamazepine (CBZ). The characterization, properties and stability of FeMn@C-800/2 were systematically investigated, obtaining the apparent first-order reaction rate of Hetero-EF was 8.9 and 17.8 times higher than that on Fe@C-800 and Mn@C-800 at the optimized conditions of current density 10 mA cm-2, catalyst dosage of 50 mg L-1 and initial pH 4.0, respectively. The incorporation of Mn promoted the generation of more Fe0 and Fe3C during the pyrolysis process, and enhanced the internal micro-electrolysis between Fe0 and carbon shell. At the same time, the presence of Mn0 also promoted the regeneration of Fe2+, and improved the activity of iron-carbon heterogeneous catalysis in the EF process, so as to degrade organic pollutants more effectively. This work would help to gain insight into the design of MOFs derived Fe-Mn bimetal catalyst and its mechanism for enhanced heterogeneous electro-Fenton.

Alpinia officinarum mediated copper oxide nanoparticles: synthesis and its antifungal activity against Colletotrichum gloeosporioides.

Green synthesis offers an environmentally friendly and cost-effective alternative for the synthesis of copper oxide nanoparticles (CuO NPs). In this study, the synthesis of CuO NPs was optimized by using copper sulfate (CuSO4) and the aqueous extract of Alpinia officinarum and its antifungal activity were investigated. The synthesized CuO NPs were characterized by UV-visible spectroscopy (UV-vis), X-ray diffraction (XRD), Fourier-transform infrared radiation spectroscopy (FT-IR), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), dynamic light scattering (DLS), and transmission electron microscopy (TEM). The results showed that the optimized conditions for the synthesis of CuO NPs were 1:2 ratio of extract and CuSO4 solution, pH 7, and 30 °C. The characteristic UV-vis peak of A. officinarum synthesized CuO NPs was at 264 nm. The synthesized CuO NPs had high crystallinity and purity and were spherical in morphology with the mean size of 46.40 nm. The synthesized CuO NPs reduced the fungal growth of Colletotrichum gloeosporioides in a dose-dependent manner. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of the CuO NPs were 125 µg·mL-1 and 500 µg·mL-1, respectively. The antifungal activity of CuO NPs may be attributed to its ability to deform the structure of fungal hyphae, induce excessive reactive oxygen species accumulation and lipid peroxidation in fungi, disrupt the mycelium cell membrane, and result cellular leakage.

A prospective marker for the prediction of postoperative deep venous thrombosis: Neutrophil extracellular traps.

Deep venous thrombosis (DVT) is a common medical complication in patients with lumbar fractures. The current study aimed to investigate the predictive value of neutrophil extracellular traps (NETs) in postoperative DVT formation in patients with lumbar fractures and to develop a nomogram relating clinical admission information for prediction. Patients who underwent open reduction and pedicle screw internal fixation in the treatment of single-segment lumbar fracture in the Department of Spine Surgery, the First Affiliated Hospital of Nanjing Medical University, from December 2020 to June 2022 were enrolled in this study. Baseline data and laboratory results were collected from enrollees, and the primary study endpoint event was the occurrence of DVT in patients after surgery. Multivariable logistic regression analysis was used to identify risk factors associated with higher odds of DVT after surgery. A nomogram was constructed using the results of the multivariable model. The calibration plot and receiver operating characteristics (ROC) curve were used to show the satisfactory predictive capacity of the model. Of these 393 patients who did not have DVT preoperatively, 79 patients developed it postoperatively, and 314 did not, respectively. Multivariate analysis showed that higher body mass index (BMI) (BMI between 24 and 28: RR = 1.661, 95% CI = 0.891-3.094; BMI ≤28: RR = 5.625, 95% CI = 2.590-12.217; reference: BMI <24), neutrophils (RR = 1.157, 95% CI 1.042-1.285), D-dimer (RR = 1.098, 95% CI 1.000-1.206), and citrullinated histone H3 (CitH3) (RR = 1.043, 95% CI 1.026-1.060) were independent risk factors for postoperative DVT. Using the multivariable analysis, we then constructed a nomogram to predict DVT, which was found to have an area under the curve of 0.757 (95% CI = 0.693-0.820). Calibration plots also showed the satisfied discrimination and calibration of the nomogram. In conclusion, patients with lumbar fractures with postoperative DVT had higher levels of NETs in the circulation preoperatively compared to those without postoperative DVT. Furthermore, based on BMI, D-dimer, neutrophils, and CitH3, we developed a predictive model to predict postoperative DVT incidence in these patients.

Pre-Treatment CRP-Albumin-Lymphocyte Index (CALLY Index) as a Prognostic Biomarker of Survival in Patients with Epithelial Ovarian Cancer.

Background: The novel CRP-albumin-lymphocyte (CALLY) index is an improved immunonutritive scoring system, based on serum C-reactive protein (CRP), serum albumin, and the lymphocyte count. It has been determined as a prognostic index for patients with hepatocellular carcinoma. This study was conducted to explore the prognostic value of the CALLY index in patients with epithelial ovarian cancer (EOC) undergoing surgery. Methods: Patients with EOC treated with surgery as an initial therapy were enrolled to form the training and validation cohorts. The effect of the CALLY index on overall survival (OS) and disease-free survival (DFS) was analyzed using Kaplan-Meier method and Cox proportional hazards model. The CALLY index was calculated as: (Albumin × Lymphocyte)/ (CRP × 104). Results: There were 190 patients in the training cohort and 120 in the validation cohort, respectively. With a cut-off value of 3, patients were classified into the CALLY <3 and CALLY ≥3 groups. The CALLY index ≥3 was associated with better survival outcomes both in the training and validation cohorts. The univariate and multivariate COX analysis revealed that FIGO stage, lymphatic metastasis, and CALLY index were the prognostic factors for both OS and DFS. Conclusion: The CALLY index is a novel prognostic biomarker for patients with EOC after surgery. The novel CALLY index could select appropriate patients with poor prognosis for postoperative adjuvant therapy.

Physiological and biochemical bases of spermidine-induced alleviation of cadmium and lead combined stress in rice.

Cadmium (Cd) and lead (Pb) pollution is a major environmental issue affecting plant production. Spermidine (Spd) is involved in plant response to abiotic stress. However, the role and associated mechanism of Spd under Cd + Pb combined stress are poorly understood. The potential protective role of Spd at different concentration on rice (Oryza sativa L.) seedlings exposed to Cd + Pb treatment was investigated by a hydroponic experiment in this study. The results showed that exogenous Spd enhanced the tolerance of rice seedlings to Cd + Pb stress, resulted in an increase in plant height, root length, fresh weight and dry weight of roots and shoots. Further, application of Spd decreased the contents of hydrogen peroxide, superoxide anion, malondialdehyde, and the accumulation of Cd and Pb, and increased the contents of mineral nutrient, carotenoids, chlorophyll, proline, soluble sugar, soluble protein, total phenol, flavonoid, anthocyanin, and antioxidant enzymes activities in roots and shoots of rice seedlings under Cd + Pb stress. Particularly, 0.5 mmol L-1 Spd was the most effective to alleviate the adverse impacts on growth and physiological metabolism of rice seedlings under Cd + Pb stress. Principal component analysis and heat map clustering established correlations between physio-biochemical parameters and further revealed Spd alleviated Cd + Pb damage in rice seedling was associated with inhibition of accumulation and translocation of Cd and Pb, increasing the contents of photosynthetic pigments and mineral nutrient and stimulation of antioxidative response and osmotic adjustment. Overall, our findings provide an important prospect for use of Spd in modulating Cd + Pb tolerance in rice plants. Spd could help to alleviate Cd + Pb damage through inhibition of accumulation and translocation of Cd and Pb and stimulation of oxidant-defense system and osmotic adjustment.

Method for identifying the impact load condition of thin-walled structure damage based on PSO-BP neural network.

Thin-walled structures (TWS) were widely used in engineering equipment, and may be subjected to impact loads to produce different degrees of structural damage during application. However, it is a difficult problem to determine the impact load conditions for these structural damages. In this study, we developed a novel method of identifying the impact load condition of the thin-walled structure damage, which is based on particle swarm optimization-backpropagation (PSO-BP) neural network. First, the known impact position and velocity are applied to the finite element model (FEM) of the TWS to produce permanent plastic deformation, and to fit the characteristic shape of the deformation is needed by invoking the multivariate polynomial function. Then, the method is devoted to build a basic data set. With impact position and velocity as input and function coefficients as output, a model of extended PSO-BP neural network is established. Besides, the basic sample set is expanded to solve the lack of samples. Ultimately, utilizing the expanded total sample set as training data, function coefficients, impact position and velocity will be outputted. On the basis of the known functional coefficients of deformed surfaces, a model of predictive PSO-BP neural network is established and predicted. Furthermore, we predicted the collision position and velocity using a conventional BP neural network in the same way. Finally, the predicted impact position and velocity is compared with the analysis results of the FEM, which verifies that the PSO-BP neural network algorithm has high accuracy.

Application of exogenous glycinebetaine alleviates lead toxicity in pakchoi (Brassica chinensis L.) by promoting antioxidant enzymes and suppressing Pb accumulation.

Lead (Pb) poses an adverse effect on plant growth and development. Glycinebetaine (GB) plays an important role in plants response to stress environment. The study was performed to examine the potential of exogenous GB (0.5, 1, 2, and 5 mM) in alleviating Pb toxicity, the physiological and biochemical responses in pakchoi under 100 µM Pb stress by hydroponic experiment. Pb stress significantly decreased the growth, contents of pigment and mineral nutrient, and activities of antioxidative enzymes (CAT, SOD, and APX) in roots and shoots of pakchoi, while it caused a significant increase in Pb and ROS accumulation both in roots and shoots of pakchoi in comparison to the control. Exogenous application of GB improved leaf and root length, fresh and dry weight, mineral nutrient, and pigment contents of pakchoi under Pb stress. GB also effectively enhanced antioxidative enzyme activities and the accumulation of proline, soluble sugar, and GB and reduced the oxidative stress and Pb contents in shoots and roots of pakchoi. Principle component analysis (PCA) provided useful information on the classification of Pb tolerance according to the response to GB. Overall, the 1 mM GB was more effective to ameliorate the detrimental impacts of Pb stress. These findings suggested that GB application might be considered an effective strategy for alleviating Pb toxicity and enhancing the tolerance of pakchoi plants under Pb stress.

Association of MicroRNA Biogenesis Genes Polymorphisms with Risk of Large Artery Atherosclerosis Stroke.

Convincing evidence has shown that microRNAs (miRNAs) are involved in the pathogenesis of stroke. This study aimed to examine whether miRNA biogenesis genes polymorphisms are associated with risk of large artery atherosclerosis (LAA) stroke. Three polymorphisms (DROSHA rs10719 T>C, RAN rs3803012 A>G, and PIWIL1 rs10773771 C>T) were screened by certain criteria. A total of 1,785 (710 cases and 1,075 controls) study subjects were included in this study. We found that rs10773771 CC genotype was associated with a decreased risk of LAA stroke (CC vs. TT/CT: OR 0.63, 95% CI 0.46-0.86, P = 3 × 10-3). In silico analysis suggested that rs10773771 can change the mRNA secondary structure of PIWIL1 and affect the binding of the miRNAs and regulatory motifs to the 3'-UTR of PIWIL1. Expression quantitative trait loci analysis showed that rs10773771 could change the expression of PIWIL1 in human skin (P = 1.534 × 10-10) and thyroid tissues (P = 4.869 × 10-6). These findings suggested that PIWIL1 rs10773771 may be associated with a decreased risk of LAA stroke.

Multifunctional Metal-Organic Framework as a Versatile Nanoplatform for Aß Oligomer Imaging and Chemo-Photothermal Treatment in Living Cells.

In view of the close association of ß-amyloid oligomers (AßO) with the clinical development of Alzheimer's disease (AD) symptoms, it is urgent to design a promising sensing and therapeutic strategy that can target AßO for preventing or delaying the onset of AD. Herein, a core-shell nanocomposite CeONP-Res-PCM@ZIF-8/polydopamine (PDA) was synthesized through an in situ encapsulated strategy, in which resveratrol (Res), ceria nanoparticles (CeONPs), and PCM (tetradecanol) were embedded into the ZIF-8/PDA matrix via a water-based mild approach. Using the AßO aptamer, the ability of CeONP-Res-PCM@ZIF-8/PDA/Apt as the fluorescent sensing platform for AßO detection and intracellular imaging was demonstrated. The nanocomposite was high in Res loading (27.5%) and could be activated to release the encapsulated Res upon illumination with NIR through PCM regulation. Moreover, due to the synergetic interactions of PDA, CeONPs, and Res in one system, CeONP-Res-PCM@ZIF-8/PDA/Apt nanocomposites exhibited multifunctional effects on inhibiting Aß aggregation, degrading Aß fibrils, and alleviating Aß-induced oxidative stress and neural apoptosis. These therapeutic effects could be enhanced under NIR irradiation by virtue of the excellent photothermal property of PDA. As far as we know, there is no report of using ZIF-8-based materials for simultaneous sensing and therapeutic applications. This work boosted the development of multifunctional nanoagents for biomedical research studies.

Method for determining load magnitude and location from the plastic deformation of fixed beams using a neural network.

Fixed beam structures are widely used in engineering, and a common problem is determining the load conditions of these structures resulting from impact loads. In this study, a method for accurately identifying the location and magnitude of the load causing plastic deformation of a fixed beam using a backpropagation artificial neural network (BP-ANN). First, a load of known location and magnitude is applied to the finite element model of a fixed beam to create plastic deformation, and a polynomial expression is used to fit the resulting deformed shape. A basic data set was established through this method for a series of calculations, and it consists of the location and magnitude of the applied load and polynomial coefficients. Then, a BP-ANN model for expanding the sample data is established and the sample set is expanded to solve the common problem of insufficient samples. Finally, using the extended sample set as training data, the coefficients of the polynomial function describing the plastic deformation of the fixed beam are used as input data, the position and magnitude of the load are used as output data, a BP-ANN prediction model is established. The prediction results are compared with the results of finite element analysis to verify the effectiveness of the method.