Search

The simultaneous observation and analysis of atmospheric particles on a regional scale is an important approach to developing control strategies for air pollution. To study the spatial distribution characteristics of particulate matter and water-soluble inorganic ions in the Ili Valley Urban agglomeration, PM

This study was designed to determine the metabolites of Yiqi Baoyuan Prescription(YQBYP) in rats. The ultra-high performance liquid chromatography coupled to time-of-flight mass spectrometry(UPLC-TOF-MS) and mass defect filter(MDF) were employed to analyze the metabolites of YQBYP in rat plasma, bile, urine and feces. Chromatographic separation was conducted on Acquity UPLC BEH C_(18) column(2.1 mm×100 mm, 1.7 μm) under gradient elution with 0.1% formic acid aqueous solution(A)-acetonitrile(B), and the column temperature was 30 ℃. Electrospray ion(ESI) source was used under positive and negative ion modes, with capillary voltage of 3.0 kV and mass scanning range of m/z 100-1 000. In this experiment, 9 prototype components and 36 metabolites were identified in rat plasma, bile, urine and feces samples. The results showed that the main metabolic pathways of YQBYP in rats involved methylation, demethylation, oxidation, and other phase Ⅰ reactions as well as glucuronidation, sulfation, and other phase Ⅱ reactions. This study provided scientific basis for clarifying the therapeutic material basis of YQBYP and product development.

Fungal keratitis (FK) is a refractory disease that poses a serious threat to vision, with common risk factors like eye trauma, contact lens wearing, topical corticosteroids and antibiotic abuse. Nowadays, topical and systemic anti-fungal drugs and ocular surgeries are still the main therapeutic modalities. However, the pathogenesis of FK, especially the immunologic mechanism within it, has not yet been deeply clarified. A better understanding of the pathogenesis of FK is imperative for more effective therapies and prognosis. Meanwhile, the immune protection strategies are also urgently required to manage FK. This review highlights recent advances in the immunologic mechanism in the pathogenesis of FK, in hope of providing valuable reference information for more effective anti-fungal treatment.

A new neolignan, (-)-(7S, 8R)-3‑methoxy-4', 7-epoxy-8, 5'-neolignane-5, 9, 3', 9′-tetraol (1) and a new biphenylpropanoid, 1, 2-epoxy-1-(3', 4'-dihydroxyphenyl-)-3-(2'', 3'', 5''-trihydroxyphenyl-) propane (2), together with eight known compounds (3-10), were isolated from the 95% EtOH extract of the leaves of Cupressus funebris Endl. Their structures were determined by spectroscopic methods including NMR, circular dichroism (CD) spectra and comparison of the NMR data with reported in references. The antioxidant activities of all compounds were evaluated by DPPH, ABTS, and FRAP methods. Compounds 2 (IC50: 33.98 ± 0.11 μM), 3 (IC50: 32.97 ± 0.63 μM), 8 (IC50: 32.07 ± 1.57 μM), and 9 (IC50: 33.30 ± 2.29 μM) showed stronger DPPH free radical scavenging activity than l -ascorbic acid (IC50: 64.31 ± 1.32 μM). Except for 4, the other compounds showed ABTS radical scavenging abilities comparable to l -ascorbic acid (54.91 ± 1.18 μM) with the IC50 ranged from 24.42 ± 1.78 μM to 138.70 ± 13.58 μM. Compound 3 (0.72 ± 0.02 mmol/g) showed the same ferric reducing antioxidant power (FRAP) as l -ascorbic acid (0.83±0.02 mmol/g).

Mounting evidence has demonstrated the important role of long non-coding RNAs (lncRNAs) in the development and progression of lung cancer. In this study, we combined the methods of bioinformatics analysis and experimental validation, and aim to investigate the clinical significance and underlying mechanism of the novel lncRNA AC079630.4 in lung cancer. Finally, we found that AC079630.4 was significantly down-regulated in lung cancer tissues, including in its subtypes. Samples with low AC079630.4 expression had a more advanced pathological stage and a worse prognosis than those with high expression. In functional prediction, the KEGG pathway of apoptosis and the TRAIL signaling pathway were enriched in the samples with high AC079630.4 expression. In experimental validation, AC079630.4 over-expression could significantly inhibit the proliferation and clonality, and up-regulated the receptors of TRAIL (TRAIL-R1 and TRAIL-R2) in lung cancer cells. In conclusion, we adopted the methods of bioinformatics analysis and experimental validation, and identified a novel lncRNA of AC079630.4 as a tumor suppressor in lung cancer.

OBJECTIVE: To study the influence of enteral feeding initiation time on intestinal flora and metabolites in very low birth weight (VLBW) infants. METHODS: A total of 29 VLBW infants who were admitted to the Department of Neonatology, Children's Hospital of Chongqing Medical University, from June to December, 2020, were enrolled as subjects. According to the enteral feeding initiation time after birth, the infants were divided into two groups: 0.05). The analysis of flora composition showed that there was no significant difference in the main microflora at the phylum and genus levels between the two groups at weeks 2 and 4 after birth (P>0.05). The comparison of SCFAs between the two groups showed that the 0.05). CONCLUSIONS: Early enteral feeding has no influence on the diversity and abundance of intestinal flora in VLBW infants, but enteral feeding within 24 hours can increase the level of propionic acid, a metabolite of intestinal flora.

Transfering large-area graphene from the metal substrate to the target substrate is crucial to its wide potential applications in electromagnetic shielding, supercapacitor, DNA sequencing, seawater desalination, wearable electronics devices, display devices for OLEDs and touch-screen. Polymethyl methacrylate assisted transfer is being widely adopted, however, this technique tends to destroy graphene and to produce polymethyl methacrylate residues on the graphene surface. Here, we reduced the damage of graphene by improving the hydrophilicity and adhesion of graphene and substrate using O2 plasma followed by heat treatment, and removed the polymethyl methacrylate residuals on the surface of graphene using hot acetone vapor. Both monolayer and multilayer graphene stacks were transferred onto the target substrate with dramatically improved surface hydrophilicity (contact angle decreased from 57.8° to 6.0°), and neither damage nor undesired residues were found. Especially, in the whole test band (400–1100 nm), all transferred graphene stacks exhibited transmittances higher than 90%. This work may bring opportunities for exploitation of large-area chemical-vapor-deposited graphene in wider transparent and ultra-thin photovoltaic devices fields.

Purpose Red blood cell (RBC) folate indicates long-term folate intake, and methylenetetrahydrofolate reductase (MTHFR) gene is the main gene affecting folate status. Increasing evidence suggests an association between gestational diabetes mellitus (GDM) and increased folate levels. Whether RBC folate concentrations in the first trimester of pregnancy or polymorphisms of MTHFR C677T (rs1801133) affect GDM risk in Chinese pregnant women remains unknown. Therefore, we analyzed the associations of RBC folate concentrations and rs1801133 polymorphisms with GDM risk among pregnant women in China. Methods A total of 366 women with a singleton pregnancy were followed prospectively from their first prenatal visit to delivery. RBC folate concentrations and rs1801133 polymorphisms were assessed during the first trimester of pregnancy. Binary logistic regression analyses were performed to determine the odds ratios (ORs) of GDM and 95% confidence intervals (CIs) by using the RBC folate concentration quartiles and rs1801133 polymorphisms. Results Participants with the TT genotype had the highest RBC folate concentrations. Those with heterozygous or homozygous variants did not have a significantly higher risk of GDM than did women with C alleles. After adjustments for covariates, women in the highest quartile for RBC folate concentration had a higher risk of GDM (adjusted OR = 2.473, 95% CI = 1.013-6.037, P = 0.047) than did those in the lowest quartile, but this association was nonsignificant after adjustment for rs1801133 polymorphisms. Conclusion Higher RBC folate, partly caused by MTHFR 677C→T, may be associated with increased GDM risk, even in early pregnancy. Assessing RBC folate status and appropriately supplementing folate during early pregnancy, particularly for patients with MTHFR 677C→T, may prevent GDM. Further studies with larger populations are warranted.

Bilayer nanofiltration (NF) membranes tend to delaminate and have poor stability when applied in organic solvents due to their bi-layered structure. In this study we prepared two types of polydopam...

Based on the online ion data, we have analyzed the cause of a PM

Background Emerging studies have shown that long noncoding RNAs (lncRNAs) predominantly function in the carcinogenesis of multiple developing human tumors. The current study aimed to investigate the underlying mechanisms of LINC00337 in lung adenocarcinoma. Methods We analyzed TCGA and GTEx datasets and chose LINC00337 as the research object. Cell proliferation, cell apoptosis, cell cycle, migration, and invasion were detected in the gain and loss experiments of LINC00337 both in vitro and in vivo. Moreover, RNA pull-down, luciferase reporter assays, western blotting analysis, and rescue experiments were performed to investigate the underlying molecular mechanisms of LINC00337 function. Results LINC00337 expression was remarkably upregulated in lung adenocarcinoma. In addition, LINC00337 knockdown was shown to repress cell migration, invasion, and proliferation, as well as the cell cycle, and gear up apoptosis in lung adenocarcinoma in vitro and in vivo. With respect to the mechanism, LINC00337 knockdown boosted miR-1285-3p expression and then restrained YTHDF1 expression post-transcriptionally. Crucially, both miR-1285-3p decrement and YTHDF1 overexpression successfully reversed the influence on cell proliferation, migration, invasion, and apoptosis caused by LINC00337 shRNA. Conclusions These results suggest that LINC00337 acts as an oncogenic lncRNA, targeting miR-1285-3p and regulating YTHDF1 expression, to promote the progression of lung adenocarcinoma.

Objectives To propose an updated definition of proximal tibia and fibula fracture (PTFF) and establish a three‐dimensional (3D) structure‐based classification of PTFF. Methods In total, 1358 adult patients (837 males and 521 females; 43.61 ± 15.13 years， 1364 affected knees) who were diagnosed with PTFF at the departments of orthopaedic surgery of four hospitals from January 2010 to December 2019 were enrolled. The new classification of PTFF, termed Wu classification, included three parts: classification of columns in the horizontal plane, regions in the frontal plane, and segments in the sagittal plane. All PTFFs were classified according to Schatzker, Luo, and Wu classification systems. Additionally, the incidence and characteristics of PTFFs were analyzed. Results The major internal structural fractures of PTFF were tibial plateau fracture (TPF) only (725, 53.15%), TPF and proximal fibular fracture (274, 20.09%), and isolated avulsion fracture of the posterior cruciate ligament (PCL) (189, 13.86%). Approximately a quarter of PTFF cases could not be classified using Schatzker or Luo classifications, but all PTFF cases could be classified using Wu classification. The most frequent PTFFs included all four columns in region IV, segment 2 (235, 17.23%); the posterolateral and posteromedial columns in region II, segment 2 (191, 14.00%); and the lateral and posterolateral columns in region IV, segment 2 (136, 9.97%). Isolated avulsion fracture of the anterior cruciate ligament (ACL) was categorized as three injury types, most of which involved the lateral and medial columns in region II, segment 1 (40/63, 64%). More than 97% of cases of isolated fractures of the PCL involved the posterolateral and posteromedial columns in region II, segment 2. The most frequent combined avulsion fracture of the ACL and PCL included all four columns in region II, segment 2 (18/24, 75%). All of the isolated avulsion fractures of the ACL were located in segment 1, and all those of the PCL in segment 2. The most common type of isolated proximal fibular fracture involved the posterolateral column in region III, segment 2 (23/26, 88%). The most frequent combined TPF and proximal fibular fracture involved all four columns in region IV, segment 2 (107/274, 39.05%). Conclusions All cases of PTFF could be classified by the new 3D Wu classification which should be beneficial for clinical diagnosis, guidance of treatment, statistical analysis, academic communication, and prognosis, and the most frequent PTFF involved all four columns in region IV, segment 2., Based on 3D structure, we established the new classification of proximal tibia and fibula fracture (PTFF) that consisted of three parts: columns in the horizontal plane with the lateral, medial, posteromedial, and posterolateral columns; regions in the frontal plane with regions I, II, III, and IV; and segments in the sagittal plane with segments 1 and 2.

Environmental-friendly cellulose-derived sponges were employed as porous templates to achieve uniform Ag deposition via a facile and economical electroless plating method. SEM and BET results confirmed an Ag layer was deposited on cellulose composite sponges without damaging the porous structure. XPS and XRD analysis demonstrated substantial interactions between porous substrates and Ag particles. When utilized as electromagnetic interference (EMI) shielding materials, a 3.2 mm thick silver-plated sponge exhibited a total shielding effectiveness (SEtotal) value of as high as 120.85 dB in the frequency range of 10–1500 MHz when the plating time was 120 min. Moreover, the conductive sponges displayed absorption-dominant mechanism to alleviate secondary radiation, making them promising candidates as high EMI shielding materials. Keywords: Cellulose-derived sponges, Electroless Ag plating, Electromagnetic interference shielding

Objective To evaluate knee scores and clinical efficacies of patients with non‐lateral unicompartmental knee osteoarthritis (OA) who randomly underwent mobile‐bearing (MB) unicompartmental knee arthroplasty (UKA), fixed‐bearing (FB) UKA, and total knee arthroplasty (TKA). Methods From September 2015 to February 2017, a prospective, randomized, parallel, single‐center trial of 180 patients (78 males and 102 females; 63.3 ± 6.9 years) with non‐lateral compartmental knee OA was performed in the first author‐affiliated hospital. The patients were randomly divided into three groups (each group included 60 patients) and received medial cemented Oxford phase 3 MB UKA, medial cemented Link FB UKA, or cemented DePuy Sigma PFC TKA, respectively. A similar perioperative management and fast‐track surgery program was carried out for all patients. The knee scores at 3‐year follow‐up after operation and clinical efficacies of these three groups of patients were recorded, investigated, and compared. Results Primarily, compared to the TKA group, the UKA groups (MB UKA and FB UKA) had shorter operative time (median 63.2 74.5) (P = 0.007), better results in all knee scores (except VAS and KSS function scores) (P 96.0°) (P = 0.001). Secondarily, compared to the TKA group, the MB UKA group showed better results in the Western Ontario and McMaster Universities index (WOMAC) stiffness (83.6 > 79.6), WOMAC total (86.3 > 83.2), Oxford knee score (OKS) (20.0 74.5), and a larger maximum flexion angle of the knee (123.0 > 96.0) (P 88.5), WOMAC stiffness (84.3 > 79.6), WOMAC function (85.2 > 81.7), WOMAC total scores (87.6 > 83.2), and a larger maximum flexion angle of the knee (119.0° > 96.0°) than the TKA group (P 0.05). There was one case with original bearing dislocation in MB UKA group. One patient with displacement of the femoral component caused by a fall injury, and another patient, who lost his life in a car accident, were involved in the FB UKA group. There was an infection case and an intermuscular vein thrombosis case in TKA group. Conclusion UKA showed more advantages than TKA; however, there was no significant difference between the MB UKA and FB UKA groups for treatment of non‐lateral compartmental knee OA., This study put forward a new concept of non‐lateral compartment knee OA, and reported result of patients with non‐lateral unicompartmental knee OA who were randomly performed MB UKA, FB UKA, and TKA. UKA showed many advantages in comparison with TKA, while there was no significant difference between MB UKA and FB UKA. We believe that our study makes a significant contribution to the literature because this is the first study to compare the clinical outcomes of patients with non‐lateral compartment knee OA, who have randomly received MB UKA, FB UKA, and TKA and show the results of self‐reported knee scores of these patients 3 years postoperatively.

Long non-coding RNAs (lncRNAs) have been reported to biologically regulate tumor progression. LncRNA MIR31HG has been identified as an oncogene in several cancer types, but its role and mechanism in glioblastoma (GBM) remain to be explored. In the present study, we detected strongly-expressed MIR31HG in GBM cells through RT-qPCR analysis. Through loss-of-function assays, we uncovered that MIR31HG exerted its oncogenic property in GBM through boosting cell proliferation and suppressing the apoptosis. Mechanistically, STAT1 was found to be as a transcription factor and played a part in activating the transcription of MIR31HG with upregulating the expression of MIR31HG in GBM. Moreover, high MIR31HG level was confirmed to induce the activation of Wnt/β-catenin signaling pathway in a variety of cancers. From subcellular fractionation and western blot assays, it was displayed that MIR31HG activated Wnt/β-catenin signaling pathway through enhancing the nuclear translocation of β-catenin. Rescue assays showed that the treatment of LiCl countervailed MIR31HG depletion-induced inhibition on GBM cell growth. In conclusion, STAT1-induced upregulation of lncRNA MIR31HG facilitates GBM cell growth by activating Wnt/β-catenin signaling pathway.

Objective Graves' disease is the most common autoimmune thyroid disease and its prevalence and clinical manifestations are disparate between females and males. Costimulatory molecules play an essential role in regulating autoimmune responses. The objective of this study was to determine if expression of inhibitory molecules was correlated with treatment by dihydrotestosterone (DHT) in an in vivo BALB/c mouse model of experimental autoimmune Graves' disease.Methods Female BALB/c mice were immunized three times with thyroid stimulating hormone receptor A-subunit encoded by adenovirus to establish a Graves' disease model. Three different doses of DHT or a matching placebo were administered by implantation of slow-release pellets a week before the first immunization. Four weeks after the third immunization, the mice were euthanatized, and then the spleen and thymus were removed. Total thyroxine and free thyroxine levels in serum of mice were detected using a radioimmunoassay kit. Real-time polymerase chain reaction was performed to estimate the expression of costimulatory molecules in lymphocytes from the spleen and thymus. Flow cytometry was used to analyze the percentage of CD4+ T cells in splenic lymphocytes. Quantitative data were compared with unpaired t-tests. Correlation between two variables was analyzed using Analysis of Variance.Results Treatment with DHT can dramatically reduce total thyroxine and free thyroxine levels. Higher expression of programmed death-1 was found in the spleen of Graves' disease mice receiving 5 mg of DHT treatment (0.635±0.296 vs. 0.327±0.212; t=2.714, P=0.014), similarly, T-cell immunoglobulin domain and mucin domain 3 (TIM-3) in both the spleen (1.004±0.338 vs. 0.646±0.314; t=2.205, P=0.022) and the thymus (0.263±0.127 vs. 0.120±0.076; t=3.221, P=0.004) also increased after 5 mg of DHT treatment compared with the parallel placebo model mice. Moreover, the percentage of CD4+ T cells declined in the splenic lymphocytes of Graves' disease mice treated with 5 mg of DHT (19.90%±3.985% vs. 24.05%±2.587%; t=2.804, P=0.012). A significant negative association was observed between expression of TIM-3 in the spleen and serum levels of total thyroxine (r=-0.7106, P=0.014) as well as free thyroxine (r=-0.6542, P=0.029).Conclusion This study demonstrates that DHT can ameliorate experimental autoimmune Graves' disease, which may occur by up-regulating expression of programmed death-1 and TIM-3 and inhibiting development of CD4+ T cells.

Background: Emerging studies have attested that long noncoding RNAs (lncRNAs) predominantly functioned in carcinogenesis of multiple developing human tumors. The current research aimed at probing the underlying participation and mechanisms of LINC00337 in lung adenocarcinoma.Methods: Here we analyzed TCGA and GTEx datasets and chose LINC00337 as research object. Cell proliferation, cell apoptosis, cell cycle, and invasion were detected in gain and loss experiment of LINC00337 both in vitro and in vivo. Moreover, RNA pull-down, luciferase reporter assays, western blotting analysis, rescue experiment were performed to investigate underlying molecular mechanisms of LINC00337 function. Results: LINC00337 was remarkably increased in lung adenocarcinoma. Also, LINC00337 knock-down was unraveled to repress cell invasion and proliferation as well as cell cycle, and gear up apoptosis in lung adenocarcinoma in vitro and in vivo. With respect to mechanism, LINC00337 knock-down boosted miR-1285-3p to be expressed and then restrained YTHDF1 to be expressed post-transcriptionally. Crucially, both miR-1285-3p decrement and YTHDF1 overexpression successfully countered the influence on cell proliferation, invasion and apoptosis caused by LINC00337 shRNA.Conclusions: These results suggest that LINC00337 acted as an oncogenic lncRNA, targeting miR-1285-3p and regulating YTHDF1 expression, to promote the progression of lung adenocarcinoma.

Peng Ju Liu,1 Yanping Liu,1 Liangkun Ma,2 Ai Min Yao,3 Xiao Yan Chen,4 Yi Xuan Hou,5 Li Ping Wu,5 Liang Yu Xia6 1Department of Clinical Nutrition, Peking Union Medical College Hospital, China Academic Medical Science and Peking Union Medical College, Beijing, People’s Republic of China; 2Department of Gynaecology and Obstetrics, Peking Union Medical College Hospital, China Academic Medical Science and Peking Union Medical College, Beijing, People’s Republic of China; 3Department of Gynaecology and Obstetrics, Shunyi District Maternal and Child Health Hospital, Beijing, People’s Republic of China; 4Department of Gynaecology and Obstetrics, Quanzhou Maternal and Child Health Hospital, Fujian, People’s Republic of China; 5Peking Union Medical College School of Nursing, Beijing, People’s Republic of China; 6Department of Clinical Laboratory, Peking Union Medical College Hospital, Peking Union Medical College Hospital, China Academic Medical Science and Peking Union Medical College, Beijing, People’s Republic of ChinaCorrespondence: Yanping Liu Tel +86-10-69159081Fax +86-10-69155551Email liuyp1227@vip.sina.comBackground/Aims: To investigate the potential of maternal first-trimester triglyceride (TG) to high-density lipoprotein cholesterol (TG/HDL-c) ratio, triglyceride glucose index (TyG) and total cholesterol (TC)/HDL-c to predict the risk of later gestational diabetes mellitus (GDM) and large for gestational age (LGA) newborn in Chinese women.Methods: We included 352 women with a singleton pregnancy, who were followed up prospectively from the first prenatal visit until delivery. Fasting glucose and plasma lipid profiles including TG, TC, HDL-c, and low-density lipoprotein cholesterol (LDL-c) were measured in the first trimester. A binary logistic regression analysis was performed to determine the odds ratios (ORs) and 95% confidence intervals (CIs) of GDM and LGA according to tertiles of those indices, respectively. Receiver-operating characteristic curve (ROC) and areas under the curve (AUC) were employed to evaluate the ability of those indices to predict the risk of GDM and LGA infants, and differences in the AUC values between them were compared.Results: Women with the top tertile of TG/HDL-c or TyG other than TC/HDL-c had a significantly higher risk of GDM (ORTG/HDL-c=2.388, 95% CI 1.026– 5.467; ORTyG=3.535, 95% CI 1.483– 8.426, respectively) and LGA infant delivery (ORTG/HDL-c=3.742, 95% CI 1.114– 12.569; ORTyG=3.011, 95% CI 1.012– 8.962, respectively) than women with the lowest tertile of TG/HDL-c or TyG after adjusting for confounders. The AUC of TG/HDL-c and TyG to detect GDM was 0.664 (95% CI 0.595– 0.733) and 0.686 (95% CI 0.615– 0.756), respectively, and that to detect LGA was 0.646 (95% CI 0.559– 0.734) and 0.643 (95% CI 0.552– 0.735), respectively (all P < 0.01). There were no statistical differences between TG/HDL-c and TyG in the ability of predicting the risk of GDM or LGA infants.Conclusion: Maternal first-trimester TG/HDL-c and TyG are both good indicators in predicting the risk of later GDM and LGA newborn, and it may be useful to evaluate them in early pregnancy.Keywords: gestational diabetes, triglyceride/HDL-c ratio, triglyceride glucose index, large for gestational age infant

A low-cost electrochemical biosensor, assisted by a new type of functional magnetic nanoparticles (NPs), has been developed to detect eosinophil cationic protein (ECP), a known biomarker of asthma, in cell culture. The heparin-modified magnetic NPs were mixed with a sample solution containing ECP. After ECP had been captured by the NPs, a magnetic field was applied behind a graphite-based screen-printed electrode. The functional magnetic NPs were attracted to the electrode, raising the ECP concentration near its surface. Because of the use of the functional magnetic NPs, the difference in the signal was amplified when applying larger sample volumes for detection, thereby enhancing the sensitivity of the biosensor. This approach provided a linear range for the analysis of the logarithm of the ECP concentration from 1 to 1000 nM, with a coefficient of determination 0.992; the limit of detection was 0.30 nM. The fabricated biosensor displayed good recovery in a cell culture medium incubated with the Beas–2 B cell line. The ability to detect the concentration of ECP in a cell culture at any time point should be useful for explaining contradictory findings regarding the relationship between the initial ECP concentration and the cell line.

In this paper, the bending response of box-section beams of finite length is investigated by using energy methods. The basic assumptions used in the present study are that the total strain energy of a box-section beam subjected to uniformly distributed loading can be simplified into a two-stage analysis process. One is the local bending response of the webs and flanges behaving as plates; the other is the overall bending response of the beam with a deformed cross-section. Analytical solutions for both static and dynamic instabilities of box section beams of finite length subjected to transverse uniformly distributed loading are derived by applying the minimum potential energy principle. To validate the analytical solutions developed, geometric nonlinear finite element analyses are also conducted. Good agreement between the present solutions and the FEA results is demonstrated. Finally, the effects of beam length on the limit critical uniformly distributed load are also discussed.

Flammutoxin (FTX), a protein from fruiting bodies of edible mushroom Flammulina velutipes, is a hemolytic pore-forming protein and a transepithelial electrical resistance-decreasing protein. FTX also acts as an antiviral protein to inhibit Tobacco mosaic virus (TMV) infection of tobacco plants. To clarify its inhibition mechanism for TMV, the following experiments were performed. The gene FTX was introduced into the vector pBinFTX and then transformed into tobacco plants using Agrobacterium tumefaciens. The transgenic tobacco plant expressing FTX showed antiviral activities, and the development of TMV in tobacco was retarded after inoculated with TMV. Not only was the appearance of mosaic symptoms postponed, but also systemic symptoms were lessened in transgenic tobacco plants than in wild-type controls. The results indicate that FTX has antiviral activities.

Background Although in vitro culture system has been optimized in the past few decades, the problem of few or no high quality embryos has been still not completely solved. Accordingly, fully understanding the regulatory mechanism of pre-implantation embryonic development would be beneficial to further optimize the in vitro embryo culture system. Recent studies have found the expression of c-kit in mouse embryo and its promotion effects on mouse embryonic development. However, it is unclear the expression, the role and the related molecular regulatory mechanism of c-kit in human pre-implantation embryo development. Therefore, the present study is to determine whether c-kit is expressed in human pre-implantation embryos, and to investigate the possible regulatory mechanism of c-kit signaling in the process of embryonic development. Methods The present study includes human immature oocytes and three pronucleus (3PN) embryos collected from 768 women (28–32 ages) undergoing IVF, and normal 2PN embryos collected from ICR mice. Samples were distributed randomly into three different experimental groups: SCF group: G-1™ (medium for culture of embryos from the pro-nucleate stage to day 3) or G-2™ (medium for culture of embryos from day3 to blastocyst stage) + HSA (Human serum album) solution + rhSCF; SCF + imanitib (c-kit inhibitor) group: G-1™ or G-2™ + HSA solution + rhSCF + imanitib; SCF + U0126 (MEK/ERK inhibitor) group: G-1™ or G-2™ + HSA solution + rhSCF + U0126; Control group: G-1™ or G-2™ + HSA solution + PBS; The rate of good quality embryos at day 3, blastulation at day 6 and good quality blastulation at day 6 were analysis. RT-PCR, western blot and immunofluorescence staining were applied to detect the target genes and proteins in samples collected from human or mice, respectively. Results c-kit was expressed ubiquitously in all human immature oocytes, 3PN embryos and 3PN blastocysts. In the experiment of human 3PN embryos, compared with other groups, SCF group showed obviously higher rate of good quality at day 3, better rate of blastocyst formation at day 6 and higher rate of good quality blastocyst formation at day 6. Furthermore, we observed a higher ETV5 expression in SCF group than that in other groups. Similar results were also found in animal experiment. Interestingly, we also found a higher phosphorylation level of MEK/ERK signal molecule in mice embryos from SCF group than those from other groups. Moreover, inhibition of MEK/ERK signaling would remarkably impeded the mice embryonic development, which might be due to the reduced ETV5 expression. Conclusions The present study firstly revealed that c-kit signaling might promote the human pre-implantation embryonic development and blastocyst formation by up-regulating the expression of ETV5 via MEK/ERK pathway. Our findings provide a new idea for optimizing the in vitro embryo culture condition during ART program, which is beneficial to obtain high quality embryos for infertile patients.