The pathological roles and potential mechanisms of vascular endothelial growth factor receptor-3 in gastric cancer.

OBJECTIVE: To investigate the roles and underlying mechanisms of vascular endothelial growth factor receptor-3 (VEGFR-3) in gastric cancer (GC). METHODS: VEGFR-3 gene expression profiles in human gastric adenocarcinoma (GAC) tissues were analysed using The Cancer Genome Atlas database. Human GC cell lines and were used for in vitro studies. Mouse models of GC and distant metastasis were used for in vivo studies. Silencing of VEGFR-3 gene expression was achieved using small interfering RNA. RESULTS: VEGFR-3 gene expression was significantly elevated in GAC tissues and GC cells. Higher VEGFR-3 expression was positively correlated with more advanced stages and a greater number of metastatic lymph nodes. In vitro studies in GC cells showed that knockdown of VEGFR-3 gene expression significantly suppressed cell proliferation and migration, but promoted apoptosis. In vivo investigations revealed that silencing of VEGFR-3 gene expression exhibited significant inhibition on tumour growth and metastasis. Further mechanistic studies showed that VEGFR-3 exerted its pathological roles by affecting the key molecules in the apoptotic and epithelial-mesenchymal transition pathways. CONCLUSION: The molecular pathways associated with VEGFR-3-mediated pathological effects could be targets in the development of novel approaches for the diagnosis, prognosis and treatment of GC.

Blood Flow Restriction Training for the Intervention of Sarcopenia: Current Stage and Future Perspective.

Sarcopenia is a geriatric syndrome that is characterized by a progressive and generalized skeletal muscle disorder and can be associated with many comorbidities, including obesity, diabetes, and fracture. Its definitions, given by the AWGS and EWGSOP, are widely used. Sarcopenia is measured by muscle strength, muscle quantity or mass and physical performance. Currently, the importance and urgency of sarcopenia have grown. The application of blood flow restriction (BFR) training has received increased attention in managing sarcopenia. BFR is accomplished using a pneumatic cuff on the proximal aspect of the exercising limb. Two main methods of exercise, aerobic exercise and resistance exercise, have been applied with BFR in treating sarcopenia. Both methods can increase muscle mass and muscle strength to a certain extent. Intricate mechanisms are involved during BFRT. Currently, the presented mechanisms mainly include responses in the blood vessels and related hormones, such as growth factors, tissue hypoxia-related factors and recruitment of muscle fiber as well as muscle satellite cells. These mechanisms contribute to the positive balance of skeletal muscle synthesis, which in turn mitigates sarcopenia. As a more suited and more effective way of treating sarcopenia and its comorbidities, BFRT can serve as an alternative to traditional exercise for people who have marked physical limitations or even show superior outcomes under low loads. However, the possibility of causing stress or muscle damage must be considered. Cuff size, pressure, training load and other variables can affect the outcome of sarcopenia, which must also be considered. Thoroughly studying these factors can help to better determine an ideal BFRT scheme and better manage sarcopenia and its associated comorbidities. As a well-tolerated and novel form of exercise, BFRT offers more potential in treating sarcopenia and involves deeper insights into the function and regulation of skeletal muscle.

Combining quantitative susceptibility mapping to radiomics in diagnosing Parkinson's disease and assessing cognitive impairment.

OBJECTIVE: To explore whether magnetic susceptibility value (MSV) and radiomics features of the nigrostriatal system could be used as imaging markers for diagnosing Parkinson's disease (PD) and its related cognitive impairment (CI). METHODS: A total of 104 PD patients and 45 age-sex-matched healthy controls (HCs) underwent quantitative susceptibility mapping (QSM). The former completed Hoehn-Yahr Stage and Montreal Cognitive Assessment (MoCA). The patients were divided into several subgroups according to disease stages, courses, and MoCA scores. The ROI was subdivided into the substantia nigra (SN), head of caudate nucleus (HCN), and putamen. The MSVs and radiomics features were obtained from QSM. The multivariable logistic regression (MLR) and support vector machine (SVM) models were constructed to diagnose PD. The correlations between MSVs, radiomics features, and MoCA scores were evaluated. RESULTS: The MSVs in bilateral SN pars compacta (SNc) of PD patients were higher than those of the HCs (p < 0.001). There were differences in some radiomics features between the two groups (p < 0.05). The MSVs of the right SNc and the radiomics features of the right SN had the highest area under the curve (AUC), respectively. The comprehensive MLR model (0.90) and SVM model (0.95) revealed better classification performance than MSVs (p < 0.05) in diagnosing PD. The MSVs from the HCN were negatively correlated with MoCA scores in PD subgroups. There were correlations between radiomics features and MoCA scores in PD patients. CONCLUSIONS: Radiomics features and MSVs of the nigrostriatal system from QSM could have crucial role in diagnosing PD and assessing CI. KEY POINTS: • The MLR and the SVM models have excellent diagnostic performance in the diagnosis of PD. • A PD diagnostic nomogram, created based on MSV and the radiomics scores of SVM model, is very convenient for clinical use. • The radiomics features of the nigrostriatal system based on QSM help to evaluate the cognitive impairment in PD patients.

Real-time parametric estimation of periodic wake-foil interactions using bioinspired pressure sensing and machine learning.

Periodic wake-foil interactions occur in the collective swimming of bio-inspired robots. Wake interaction pattern estimation (and control) is crucial to thrust enhancement and propulsive efficiency optimization. In this paper, we study the wake interaction pattern estimation of two flapping foils in tandem configurations. The experiments are conducted at a Reynolds number of 1.41 × 104in a water channel. A modified wake-foil phase parameter Φ, which unifies the influences of inter-foil distanceLx, motion phase difference Δφand wake convection velocityUv, is introduced to describe the wake interaction patterns parametrically. We use a differential pressure sensor on the downstream foil to capture wake interaction characteristics. Data sets at different tandem configurations are collected. The wake-foil phase Φ is used to label the pressure signals. A one-dimensional convolutional neural networks (1D-CNN) model is used to learn an end-to-end mapping between the raw pressure measurements and the wake-foil phase Φ. The trained 1D-CNN model shows accurate estimations (average error 3.5%) on random wake interaction patterns and is fast enough (within 40 ms). Then the trained 1D-CNN model is applied to online thrust enhancement control of a downstream foil swimming in a periodic wake. Synchronous force monitoring and flow visualization demonstrate the effectiveness of the 1D-CNN model. The limitations of the model are discussed. The proposed approach can be applied to the online estimation and control of wake interactions in the collective swimming and flying of biomimetic robots.

Optimal Cut-Off Values of Visceral Fat Area for Predicting Metabolic Syndrome Among Type 2 Diabetes Patients in Ningbo, China.

OBJECTIVE: To examine the optimal cut-off values of visceral fat area (VFA) for predicting metabolic syndrome (MetS) among type 2 diabetes (T2D) patients in Ningbo China. METHODS: A total of 1017 subjects were selected from T2D patients who accepted standardized management by the National Standardized Metabolic Disease Management Center at Ningbo First Hospital from March 2018 to January 2020. Demography and medical information were collected through questionnaires. Regional adiposity was examined by a visceral fat analyzer using the dual bioelectrical impedance method. RESULTS: Overall, 769 (75.6%) T2D patients were defined to have MetS. Patients with MetS had higher anthropometric values and biomarkers, compared to those without MetS. VFA was significantly correlated with risk factors of MetS. Further logistic regression models showed that VFA was significantly associated with MetS in men (OR=1.02) and in women (OR=1.03) (P<0.001 for both genders) after controlling for related factors. Receiver-operating characteristic curve analysis demonstrated that the optimal cut-off values of VFA were 84.7 cm2 for men and 81.1 cm2 for women to predict MetS in T2D patients. CONCLUSION: VFA was associated with MetS and could be an independent predictor of MetS in T2D patients. CLINICAL TRIAL REGISTRATION: www.ClinicalTrials.gov, number: NCT03811470.

An organophosphorus-mediated cross-Rauhut-Currier/Wittig domino reaction for the efficient synthesis of trisubstituted cyclopentenes.

An efficient organophosphorus-mediated cross-Rauhut-Currier/Wittig domino reaction of vinyl ketones with chalcones has been developed for the synthesis of trisubstituted cyclopentenes. The new synthetic method has the advantages of mild reaction conditions, high efficiency, environmental friendliness and satisfactory yields.

DL-3-n-butylphthalide alleviates vascular cognitive impairment by regulating endoplasmic reticulum stress and the Shh/Ptch1 signaling-pathway in rats.

BACKGROUND: DL-3-n-butylphthalide (NBP) has been approved to be effective in improving cognitive deficits. The aim of the current study was to determine whether NBP protects against cognitive deficits in a rat model of vascular dementia (VD) induced by chronic cerebral hypoperfusion (CCH) by regulating the sonic hedgehog (Shh)/patched1 (Ptch1) pathway and endoplasmic reticulum stress (ERS)-related markers. METHODS: Adult male Sprague-Dawley rats were subjected to permanent bilateral occlusion of the common carotid arteries (2VO) to established the model of VD. These rats were randomly divided into five groups: sham, model, NBP30 (30 mg/kg), NBP 60 (60 mg/kg), and NBP 120 (120 mg/kg) groups. The Morris water maze test was used to assess for cognitive function at 4 weeks after operation. RESULTS: NBP significantly alleviated spatial learning and memory impairment, and inhibited the loss of neurons in the CA1 region of the hippocampus. Western blot analysis and real-time quantitative polymerase chain reaction analysis revealed that plasticity-related synaptic markers and the Shh/Ptch1 pathway significantly increased in the NBP treated groups, while ERS-related markers decreased. CONCLUSION: The results of the current study prove that the Shh/Ptch1 pathway plays an essential role in the model of VD. NBP had protective effects on cognitive impairment induced by CCH. This mechanism was associated with ERS and the Shh/Ptch1 pathway. Meanwhile, the Shh/Ptch1 pathway and ERS may interact with each other.

Comparisons of Effects on Intestinal Short-Chain Fatty Acid Concentration after Exposure of Two Glycosidase Inhibitors in Mice.

Acarbose and voglibose are the most widely used diabetes drugs as glycosidase inhibitors. In this study, the use of these two inhibitors significantly increased the content of starch in large intestine, and altered the concentration of short-chain fatty acids (SCFAs) by affecting the intestinal microbiota. However, there are some differences in the intestinal microbiome of the two groups of mice, mainly in bacteria such as Bacteroidaceae bacteroides and Desulfovibrionaceae desulfovibrio. The productions of acetate and propionate in caecum in voglibose group were significantly higher than those in acarbose group and two kinds of glycosidase inhibitors were close in the production of butyrate in caecum. The Tax4Fun analysis based on Kyoto Encyclopedia of Genes and Genomes (KEGG) data indicated that different productions of acetate and propionate between acarbose group and voglibose group may be related to 2-oxoisovalerate dehydrogenase and pyruvate oxidase. In addition, in-vitro experiments suggested that voglibose had less effect on epithelial cells than acarbose after direct stimulation. According to the recent researches of SCFAs produced by intestinal microbiota, our comparative study shown higher concentration of these beneficial fatty acids in the lumen of voglibose-treated mice, which implied a lower level of inflammation.

A Cascade Dehydrogenative Cross-Coupling/Annulation Reaction of Benzamides with ß-Keto Esters for the Synthesis of Isoquinolinone Derivatives.

A novel cascade DCC/annulation reaction of N-alkoxybenzamides with ß-keto esters has been developed for the synthesis of isoquinolinone derivatives under palladium catalysis. A plausible mechanism involving α-C(sp2)-H activation and a Pd(II)/Pd(IV) catalytic cycle is also proposed.

Cascade C-H Functionalization/Amidation Reaction for Synthesis of Azepinone Derivatives.

A cascade C-H functionalization/amidation reaction of aminobiaryls with diazomalonates has been developed under rhodium catalysis, affording new azepinone derivatives in moderate to excellent yields.

[Spatial-temporal and environmental effects of catch rate on Antarctic krill fishery in the South Georgia Island in the austral winter season based on the fine scale data].

The waters around the South Georgia Island is one of the main fishing ground of Antarctic krill fishery and many predators such as sea seal and whale inhabited this island target Antarctic krill as a food source. So it is very important for further understanding Antarctic ecosystem to conduct the research on abundance fluctuation of Antarctic krill resource around this island. Consequently, based on the fine scale fishery data collected in the winter 2013, using the generalized additive model (GAM), the present study analyzed the relationship between environmental factors and the catch rate of Antarctic krill. The results showed the model could explain 32.0% of the accumulation of deviance of the catch rate. The variable that provided the maximum contribution was ten-day with a contribution rate of 21.4% and followed by the latitude (4.4%). Generally, the catch rate decreased from the first 10 days of July to September. Higher catch rates occurred in the eastern fishing ground, particularly the central-eastern part of survey area, and lower catch rates presented in the northern part. The mean catch rate deceased with the increasing change rate of bathymetry. The oceanographic condition with wind scale below 4 was suitable for fishing operation and associated with the higher catch rate, but the wind direction did not significantly affect the catch rate. The mean catch rate increased with the increasing sea surface temperature within 0.5 to 2.0 degrees C.

Down-regulation of eIF5A-2 prevents epithelial-mesenchymal transition in non-small-cell lung cancer cells.

BACKGROUND: Epithelial-mesenchymal transition (EMT) is believed to be the critical process in malignant tumor invasion and metastases, and has a great influence on improving the survival rate in non-small-cell lung cancer (NSCLC) patients. Recent studies suggested that eukaryotic initiation factor 5A-2 (eIF5A-2) might serve as an adverse prognostic marker of survival. We detected eIF5A-2 in NSCLC A549 cells, and found that the invasive capability correlates with the eIF5A-2 expression. METHODS: Transforming growth factor (TGF)-ß1 was used to induce EMT in A549 cells. Western blotting, immunofluorescence, wound healing assay, and transwell-matrigel invasion chambers were used to identify phenotype changes. Western blotting was also used to observe changes of the expression of eIF5A-2. We down-regulated the eIF5A-2 expression using an eIF5A-2 siRNA and identified the phenotype changes by western blotting and immunofluorescence. We tested the change of migration and invasion capabilities of A549 cells by the wound healing assay and transwell-matrigel invasion chambers. RESULTS: After stimulating with TGF-ß1, almost all A549 cells changed to the mesenchymal phenotype and acquired more migration and invasion capabilities. These cells also had higher eIF5A-2 protein expression. Down-regulation of eIF5A-2 expression with eIF5A-2 siRNA transfection could change the cells from mesenchymal to epithelial phenotype and decrease tumor cell migration and invasive capabilities significantly. CONCLUSIONS: The expression of eIF5A-2 was up-regulated following EMT phenotype changes in A549 cells, which correlated with enhanced tumor invasion and metastatic capabilities. Furthermore, in the A549 cell line, the process of EMT phenotype change could be reversed by eIF5A-2 siRNA, with a consequent weakening of both invasive and metastatic capabilities.

HCV NS5A and NS5B enhance expression of human ceramide glucosyltransferase gene.

Host genes involved in lipid metabolism are differentially affected during the early stages of hepatitis C virus (HCV) infection. Here we demonstrate that artificial up-regulation of fatty acid biosynthesis has a positive effect on the replication of the HCV full-length replicon when cells were treated with nystatin. Conversely, the HCV RNA replication was decreased when fatty acid biosynthesis was inhibited with 25-hydroxycholesterol and PDMP(D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol). In agreement with these results, the expression level of GlcT-1(ceramide glucosyltransferase), a host glucosyltransferase in the first step of GSL (glycosphingolipid) biosynthesis, was found to be closely associated with the expression and replication of HCV RNA. On the other hand, the viral RNA can also activate GlcT-1 in the early stage of viral RNA transfection in vitro. To identify viral factors that are responsible for GlcT-1 activation, we constructed ten stable Vero cell lines that express individual HCV proteins. Based on the analyses of these cell lines and transient transfection assay of the GlcT-1 promoter regions, we conclude that HCV proteins, especially NS5A and NS5B, have positive effects on the expression of GlcT-1. It is possible that NS5A and NS5B stimulate transcription factor(s) to activate the expression of GlcT-1 by increasing its transcription level.

Macrophage-induced tumor angiogenesis is regulated by the TSC2-mTOR pathway.

Tumor-associated macrophages (TAM) have multifaceted roles in tumor development but they have been associated particularly closely with tumor angiogenesis. However, although the accumulation of TAM (M2 phenotype) promotes tumor angiogenesis, the mechanism through which monocytes differentiate to generate TAM is unclear. Here, we report that the mTOR pathway is a critical element in the regulation of monocyte differentiation to TAM. In human peripheral monocytes stimulated by lipopolysaccharide, mTOR was inhibited by rapamycin or activated by RNA interference-mediated knockdown of the mTOR repressor tuberous sclerosis complex 2 (TSC2). Rapamycin caused the monocytes to differentiate into M1 macrophages releasing more interleukin (IL)-12 and less IL-10, whereas TSC2 knockdown caused the monocytes to differentiate into M2 macrophages releasing less IL-12 and more IL-10. In parallel fashion, angiogenic properties were promoted or reduced in human umbilical vein endothelial cells cocultured with TSC2-deficient monocytes or rapamycin-treated monocytes, respectively. Furthermore, tumor angiogenesis and growth in murine xenografts were promoted or reduced by infusion of hosts with TSC2-deficient or TSC2-overexpressing monocytes, respectively. Finally, in vivo depletion of macrophages was sufficient to block the antiangiogenic effects of rapamycin on tumors. Our results define the TSC2-mTOR pathway as a key determinant in the differentiation of monocytes into M2 phenotype TAM that promote angiogenesis.

Correlation of Chimerism with Acute Graft-versus-Host Disease in Rats following Liver Transplantation.

The accurate diagnosis of acute graft-versus-host disease following liver transplantation (LTx-aGVHD) has been hampered. Chimerism appears in the majority of recipients after LT and its significance in the diagnosis of LTx-aGVHD has not been clearly established. To demonstrate the significance of chimerism on the diagnosis of LTx-aGVHD, we compared the change of chimerism in syngeneic LT recipients, semiallogeneic LT recipients, and LTx-aGVHD induced recipients. Chimerism in PBMCs following sex-mismatched LT was identified by real-time PCR based on a rat Y-chromosome-specific primer. All recipients in semiallogeneic group grew in a normal pattern. However, when 4 × 10(8) donor splenocytes were transferred simultaneously during LT, the morbidity of lethal aGVHD was 100%. The chimerism appeared slightly higher in the semiallogeneic group than in the syngeneic LT group, but the difference was not significant. However, when the recipients developed lethal aGVHD after LT, chimerism in the PBMCs increased progressively, and even at an early time, a significant increase in chimerism was observed. In conclusion, high level chimerism correlated well with LTx-aGVHD, and detection of chimerism soon after transplantation may be of value in the diagnosis of LTx-aGVHD prior to the onset of symptoms.

Changes of sphingolipids profiles after ischemia-reperfusion injury in the rat liver.

BACKGROUND: Hepatic ischemia-reperfusion (I/R) injury occurs in many clinical procedures. The molecular mechanisms responsible for hepatic I/R injury however remain unknown. Sphingolipids, in particular ceramide, play a role in stress and death receptor-induced hepatocellular death, contributing to the progression of several liver diseases including liver I/R injury. In order to further define the role of sphingolipids in hepatic I/R, systemic analysis of sphingolipids after reperfusion is necessary. METHODS: We investigated the lipidomic changes of sphingolipids in a rat model of warm hepatic I/R injury, by delayed extraction matrix-assisted laser desorption ionization time-of-flight mass spectrometry (DE MALDI-TOF-MS). RESULTS: The total amounts of ceramide and sphingomyelin and the intensity of most kinds of sphingolipids, mainly sphingomyelin, significantly increased at 1 hour after reperfusion (P < 0.05) and reached peaks at 6 hours after reperfusion (P < 0.01) compared to controls. Six new forms of ceramide and sphingomyelins appeared 6 hours after reperfusion, they were (m/z) 537.8, 555.7, 567.7, 583.8, 683.5 and 731.4 respectively. A ceramide-monohexoside (m/z) 804.4 (CMH(d18:1C22:1+Na)(+)) also increased after reperfusion and correlated with extent of liver injury after reperfursion. CONCLUSIONS: Three main forms of sphingolipids, ceramide, sphingomyelin and ceramide-monohexoside, are related to hepatic I/R injury and provide a new perspective in understanding the mechanisms responsible for hepatic I/R injury.

[Expression and study of the functional proteins of hepatitis C virus in CHO cell line].

Recently, the interactions between hepatitis C virus (HCV) genes and the host cell factors were the focus of this field. Cell factors in the different biochemical pathway were approved to be interfered when HCV infection. To make sure which HCV gene(s) was the major factor during the interaction process, ten eukaryotic expression plasmids containing different functional genes of HCV: Core, E1, E2, p7, NS2, NS3, NS4A, NS4B, NS5A and NS5B were transfected into the CHO-K1 cells respectively. Then ten stable cell lines expressing different HCV functional proteins were constructed under the selective pressure of G418. DNA and mRNA of the HCV genes were both detected by PCR and RT-PCR respectively in the corresponding stable cell lines, freezation and anabiosis would not lose the HCV genes. Besides, the El, E2 and NS5B proteins were detected by Western-blot which demonstrated that the HCV genes have formed stable expression in the host cells. The activity of UDP-glucose ceramide glucosyltransferase (UGCG) in the stable cell lines increased in different degree by TLC assay. For example, the activity of UGCG in CHO-K1-E2 and CHO-K1-p7 was doubled according to the control cells,and in CHO-K1-NS2 and CHO-K1-NS5A was about 1.6 times compared with the control cells. The establishment of the stable cell lines containing different single HCV gene will provide foundation for investigating the interactions between the virus and the host factors, and for the filtration of antiviral medicine.

[Relationship between respiration exchange ratio and muscle oxygen content measured by near-infrared spectroscopy].

OBJECTIVE: To study the relationship between respiration exchange ratio (RER) and tissue oxygen content in human skeletal muscle. METHOD: Using a portable tissue oximeter based on near-infrared spectroscopy (NIRS), the relative changes of skeletal muscle oxygen content were measured non-invasively and in vivo when healthy volunteers were performing an incremental intensity running protocol. The results were compared with heart rate (HR), VO2, VCO2, and RER. RESULT: In the experiment, the change in skeletal muscle oxygenation content of the volunteers was regular and has a significant close relationship to HR, VO2 and RER (P=0.01). CONCLUSION: It shows that NIRS is a new photonic technology which provides a measurable biomedical parameter for the evaluation of athlete's physique and training effect. It offers reference for monitoring and assessing training effect in vivo, real-time and non-invasively.

[Blood oxygen and lactate concentrations in skeletal muscles during exercise].

OBJECTIVE: To study the relationship between blood lactate and blood oxygenation in human skeletal muscle. METHOD: Using a portable tissue oximeter based on Near-Infrared Spectroscopy (NIRS), concentration of HbO2, blood lactate and blood volume were measured non-invasively and continuously when the subjects were doing incremental exercise on a bicycle ergometer. RESULT: As the intensity of exercise was increased, blood lactate concentration, blood volume in tissue increased, while concentration of HbO2 decreased. CONCLUSION: It is possible to assess the fatigue state with tissue oximeter by monitoring intensity of exercise non-invasively and dynamically. By studying their correlations, a novel approach for measuring blood lactate non-invasively and assessing sports ability could be provided.