Search

Background Intestinal barrier dysfunction is the critical link of distant organ injury caused by hemorrhagic shock. The role of autophagy in ischemic intestinal injury has been paid more and more attention. Prophylactic treatment of stellate ganglion block (SGB) reduces intestinal barrier dysfunction induced by haemorrhagic shock. This study investigated the role of SGB post-processing on improved bowel barrier function and autophagy-related mechanisms of action after haemorrhagic shock. Methods The model of hemorrhagic shock in conscious rats was established, and the rats were treated with SGB, autophagy inhibitor 3- methyladenine (3-MA) at the time of fluid resuscitation. We detected the survival rate, intestinal loop blood flow, intestinal barrier permeability, intestinal morphology, wet/dry ratio (W/D), the intestinal barrier and autophagy marker proteins. Simultaneously, we also observed the effect of autophagy activator rapamycin (RAPA) on SGB. Results SGB postconditioning significantly prolonged the overall survival and enhanced survival rate of 72 hours in rats after hemorrhagic shock. SGB post-processing and 3-MA administration improved the intestinal morphology and intestinal permeability, increased the intestinal loop blood flow and expression of ZO1, Occludin and Claudin-1, and decreased the intestinal W/D and LC3 and Beclin-1 expressions, expected for increased P62. Meanwhile, RAPA partially inhibited the effect of SGB on above indices in haemorrhagic shock rats. Conclusion SGB postconditioning alleviates the intestinal barrier dysfunction caused by haemorrhagic shock, which is related to the inhibition of excessive autophagy.

The mortality rate of critically ill patients with acute respiratory distress syndrome (ARDS) is 30.9% to 46.1%. The emergence of the coronavirus disease 2019 (Covid-19) has become a global issue with raising dire concerns. Patients with severe Covid-19 may progress toward ARDS. Mesenchymal stem cells (MSCs) can be derived from bone marrow, umbilical cord, adipose tissue and so on. The easy accessibility and low immunogenicity enable MSCs for allogeneic administration, and thus they were widely used in animal and clinical studies. Accumulating evidence suggests that mesenchymal stem cell infusion can ameliorate ARDS. However, the underlying mechanisms of MSCs need to be discussed. Recent studies showed MSCs can modulate immune/inflammatory cells, attenuate endoplasmic reticulum stress, and inhibit pulmonary fibrosis. The paracrine cytokines and exosomes may account for these beneficial effects. In this review, we summarize the therapeutic mechanisms of MSCs in ARDS, analyzed the most recent animal experiments and Covid-19 clinical trial results, discussed the adverse effects and prospects in the recent studies, and highlight the potential roles of MSC therapy for Covid-19 patients with ARDS.

The neutron flux monitor (NFM) system is an important diagnostic subsystem introduced by large nuclear fusion devices such as international thermonuclear experimental reactor (ITER), Japan torus-60, tokamak fusion test reactor, and HL-2A. Neutron fluxes can provide real-time parameters for nuclear fusion, including neutron source intensity and fusion power. Corresponding to different nuclear reaction periods, neutron fluxes span over seven decades, thereby requiring electronic devices to operate in counting and Campbelling modes simultaneously. Therefore, it is crucial to design a real-time NFM system to encompass such a wide dynamic range. In this study, a high-precision NFM system with a wide measurement range of neutron flux is implemented using real-time multipoint linear calibration. It can automatically switch between counting and Campbelling modes with variations in the neutron flux. We established a testing platform to verify the feasibility of the NFM system, which can output the simulated neutron signal using an arbitrary waveform generator. Meanwhile, the accurate calibration interval of the Campbelling mode is defined well. Based on the above-mentioned design, the system satisfies the requirements, offering a dynamic range of 108 cps, temporal resolution of 1 ms, and maximal relative error of 4% measured at the signal-to-noise ratio of 15.8 dB. Additionally, the NFM system is verified in a field experiment involving HL-2A, and the measured neutron flux is consistent with the results.

Seafaring as a matter of human resources is one of important shipping policies in a country. Many developed countries are facing the problems of shortage of qualified and skilled seafarers for their maritime industries. Although previous researches tried to unravel the scarce seafarer dilemma, there are very few studies especially in the discussion of the factors affecting the intention to work on-board or go seafaring. This research investigates the effects of shipping knowledge, attitude and reference group opinions on the intention of maritime students to work on-board basing on the knowledge, attitude and intention (KAI) model. Using questionnaire surveys collected from 243 students studying in the maritime and logistics related departments at The Hong Kong Polytechnic University (PolyU) and Maritime Services Training Institute (MSTI) in Hong Kong. This research finds that the attitude and reference group opinions positively influence students’ intention to work on-board. Although the research hypothesis of the direct influence of shipping knowledge on the intention to work on-board was not supported. Specifically, this research finds the indirect influence of shipping knowledge and reference group opinions on students’ on-board intention through attitude. This research provides a comprehensive insight to understand the determinants of students’ on-board intention. Managerial and theoretical implications from the research findings are discussed in this research.

Campbell Mode is a method widely used in nuclear signal processing. In this article, we introduce the design of the new system based on the Campbell integration measurement applied in NFM (neutron flux measurement) systems for ITER plasma diagnose. In this article, we introduce a digital particle flux measurement system based on Campbell integration theory. A subsequent series of experiment are conducted to test the digital Campbell system performance, which proves that the Campbell integration system is competent for the plasma diagnose in ITER.

The passenger value is used to segment the intercity passenger transport market. According to its advantages or disadvantages in each submarket, highway passenger transport (referred to as ...

Timosaponin A‑III (TAIII) is a saponin isolated from anemarrhena asphodeloides and possesses the inhibitory effect on proliferation of multiple tumor cells. In the present study, the antitumor effect of TAIII and its underlying molecular mechanisms were investigated in vitro in T‑cell acute lymphoblastic leukemia (T‑ALL) Jurkat cells. The results demonstrated that TAIII inhibits the viability of Jurkat cells in a time‑ and dose‑dependent manner, and induces apoptosis of Jurkat cells in a dose‑dependent manner. Transmission electron microscopy demonstrated the formation of numerous autophagosomes in TAIII‑treated Jurkat cells. Furthermore, monodansylcadaverine (MDC)‑labeled autophagic vacuoles were observed following TAIII treatment by an inverted fluorescence microscope and MDC accumulation increased notably in TAIII treatment groups in a concentration‑dependent manner. B‑cell lymphoma‑2 (Bcl‑2)‑associated X (Bax) was upregulated while Bcl‑2 was reduced following TAIII treatment, indicating that the pro‑apoptotic mechanism of TAIII may be associated with upregulation of Bax. Further investigation revealed that TAIII promotes the expression of autophagy‑associated proteins Beclin 1 and LC3‑II, and inhibits the phosphoinositide 3‑kinase/Akt/mechanistic target of rapamycin kinase pathway. The present study revealed that the antitumor activity of TAIII was primarily achieved by the induction of cell apoptosis and autophagy, indicating a promising potential as a novel effective reagent against T‑ALL.

The detection efficiency of the fission chamber (FC) is very important for studying the neutron flux measurement (NFM) system in ITER. In this article, we mainly focus our attention on the influence of the moderator. With the Monte Carlo particle transport simulation tool named Geant4, we make a simulation of FC detection efficiency with different levels of thickness of a beryllium moderator. Two manufactured FCs for ITER-NFM systems are then used to test the parameters and performance. The test results agree well with our simulation.

This paper puts forward an idea of designing a surface acoustic wave (SAW) sensor to provide a research basis for subsequent researchers. We have made a SAW temperature sensor based on this idea. The experimental results demonstrated the feasibility of the idea, and shown that the frequency-temperature characteristic of the sensing unit is good and the temperature measurement accuracy of the testing unit is high.

Acoustic Emission (AE) may be defined as a transient elastic stress wave generated by the rapid release of strain energy in local area of material. To overcome the limitation of some traditional techniques, the AE technique, which provides high sensitivity and responding speed, were developed in the present paper. AE signature is usually difficult to be extracted and characterized in grinding process of 1Cr18Ni9Ti coatings due to their high hardness, great ductility, inhomogeneous structure and irregular surface with lots of hard points and pores. In this paper, AE signal of stationary grinding status before wheel-workpiece contact was characterized first, then AE signal of the grinding process was analyzed using root-mean-square (RMS) and power spectrum method. Results showed that before the contact occurred, the grinding signal is stable, with low amplitude and frequency ranging all frequency channels and no peak signal. However, when contact occurred, the RMS and spectrum of AE signal increased obviously and the bandwidth varied exquisitely between 100 KHz and 300 KHz. The real contact time between wheel and workpiece was about 0.5 to 1 ms.

Transcription factor prospero homeobox 1 (Prox-1) and podoplanin (PDPN), mucin-type transmembane protein, are both constantly expressed in lymphatic endothelial cells (LECs) and appear to function in an LEC-autonomous manner. Mice globally lacking PDPN (Pdpn(-/-)) develop abnormal and blood-filled lymphatic vessels that highly resemble those in inducible mice lacking Prox-1 (Prox1(-/-)). Prox1 has also been reported to induce PDPN expression in cultured ECs. Thus, we hypothesize that PDPN functions downstream of Prox1 and that its expression is regulated by Prox1 in LECs at the transcriptional level. We first identified four putative binding elements for Prox1 in the 5' upstream regulatory region of Pdpn gene and found that Prox1 directly binds to the 5' regulatory sequence of Pdpn gene in LECs by chromatin immunoprecipitation assay. DNA pull down assay confirmed that Prox1 binds to the putative binding element. In addition, luciferase reporter assay indicated that Prox1 binding to the 5' regulatory sequence of Pdpn regulates Pdpn gene expression. We are therefore the first to experimentally demonstrate that Prox1 regulates PDPN expression at the transcriptional level in the lymphatic vascular system.

To study serum levels of heart-type fatty acid-binding protein (h-FABP) in children with chronic heart failure (CHF), and the correlation between heart function and the level of h-FABP, with the aim of studying the significance of h-FABP in CHF.Thirty-six children with CHF, including 16 cases of endocardial fibroelastosis (EFE) and 20 cases of dilated cardiomyopathy (DCM) were enrolled in the study. Thirty healthy children sevred as the control group. Serum levels of h-FABP were determined using ELISA, and left ventricular ejection fraction (LVEF), cardiac index (CI) and fractional shortening of the left ventricle (LVSF) were measured by two-dimensional echocardiography in the CHF group.Mean levels of h-FABP in the CHF group were significantly higher than in the control group (21.7±4.3 ng/mL vs 6.2±1.7 ng/mL; P0.01). The worse the heart function, the higher the h-FABP levels (P0.01). Mean levels of h-FABP in both the EFE and DCM groups were significantly higher than in the control group (P0.01). Serum h-FABP concentrations were negatively correlated with LVEF, CI and LVSF (r=-0.65, -0.64 and -0.71 respectively; P0.01) in the CHF group.Serum h-FABP levels increase in children with CHF and are closely related to the severity of the condition. Serum h-FABP levels can be used as a biomarker for the diagnosis of heart failure and the evaluation of its severity.

To study serum levels of brain natriuretic peptide (BNP) in children with Kawasaki disease (KD) and the correlation between BNP levels and the heart function.Forty-three children with KD and thirty healthy children were enrolled. Serum levels of BNP were measured using ELISA. KD children received an echocardiographic examination, including measurements of left ventricular ejection fraction (LVEF), left ventricular shorten fraction (LVSF), cardiac index (CI) and left ventricular inflow velocity through the mitral annulus.Mean serum level of BNP at the acute stage in children with KD was significantly higher than that at the recovery stage as well as the control group (p0.01). The LVEF, LVSF and CI levels at the acute stage were significantly lower than those at the recovery stage in children with KD (p0.05). The linear regression analysis showed that the BNP level was negatively correlated with the levels of LVEF, LVSF and CI (r=-0.63, -0.52, -0.53, p0.05).The serum BNP levels increase significantly in KD children at the acute stage, and are negatively correlated with the levels of LVEF, LVSF and CI. Measurement of serum BNP level is useful for the early diagnosis of KD.

Kawasaki disease (KD) is a common cause of acquired heart disease in children. Recent studies have focused on the biochemical markers of the myocardium, their high sensitivity and specificity and significance in the diagnosis of KD. This study aimed to determine the serum level of brain natriuretic peptide (BNP) and its relation with the heart function of children with KD and to explore its clinical value in diagnosis of KD.Forty-three KD children, aged from 5 months to 8 years (mean 2.3±0.6 years), were admitted to Qingdao Children's Hospital from February 2007 to April 2009. Among them 27 were male, and 16 female. The 43 patients served as a KD group. Patients with myocarditis, cardiomyopathy, congenital heart disease and other primary heart diseases were excluded. Thirty healthy children, aged from 3 months to 15 years (mean 2.5±0.8 years) or 17 males and 13 females served as a control group. There were no significant differences in age and gender between the two groups (P0.05). In the KD group, ELISA was used to measure the levels of serum BNP in acute and convalescent stages; and in the control group, the levels of serum BNP were measured once randomly. Left ventricular ejection fraction (LVEF), left ventricular shorten fraction (LVSF), cardiac index (CI) and left ventricular inflow velocity through the mitral annulus (including E-velocity and A-velocity) were measured by two-dimensional echocardiography in the acute and convalescent stages in the KD group. All data were expressed as mean±SD. The methods of analysis included Student's t test and the linear regression analysis test. P0.05 was considered statistically significant.The level of serum BNP in the acute stage (517.26±213.40) ng/ml was significantly higher than that in the convalescent stage (91.56±47.97) ng/ml in the control group (37.55±7.56) ng/ml (P0.01). The levels of LVEF, LVSF and CI in the acute stage were significantly lower than those in the convalescent stage (P0.05), but the E/A level was not significantly different between the acute and convalescent stages (P0.05). Linear regression analysis showed that the BNP level was negatively correlated with the levels of LVEF, LVSF and CI(r=-0.63, -0.52, -0.53, P0.05), but not significantly correlated with the E/A level (r=-0.18, P0.05).The levels of serum BNP are significantly increased in KD patients, and are negatively correlated with the levels of LVEF, LVSF, and CI. The detection of serum BNP level is of clinical significance in the diagnosis of KD.

Piperazine is one of the heterocycles which are associated with diverse pharmacological activities. 2-N,N-Diethylaminocarbonyloxymethyl-1-diphenylmethyl-4-(3,4,5-trimethoxybenzoyl) piperazine hydrochloride (PMS-1077) is a trisubstituted piperazine which contains a trimethoxybenzene ring and a benzhydrylpiperazine fragment, both of which can induce cell proliferation regression by different mechanisms. We have therefore examined the effects of PMS-1077 on Human Burkitt's lymphoma cells (Raji). The viability of Raji cells was determined by MTT assay and also assessed by trypan blue dye exclusion method. The results demonstrate that PMS-1077 can suppress the proliferation of Raji cells in a dose- and timedependent manner, while inhibit colony formation ability of Raji cells merely in a dose-dependent manner in vitro. Meanwhile, morphological changes were observed using fluorescence microscope. Flow cytometric analysis through PI stains showed that PMS-1077 blocked the growth of Raji cells in the G(0)/G(1) period, and induced apoptosis of Raji cells after 48 h of incubation. Cell apoptosis induced by PMS-1077 was further confirmed by staining with Annexin-V FITC and PI. Preliminary study by molecular docking suggests that PMS-1077 may inhibit tubulin polymerization. More experiments are in progress in our laboratory to reveal the mode of action of PMS-1077 in the induction of apoptosis of Raji cells.

To assess the values of serum fatty acid-binding protein (FABP) and brain natriuretic peptide (BNP) in pneumonia complicated by acute congestive heart failure (CHF) in children.Serum levels of FABP and BNP were determined using ELISA in 36 children with pneumonia complicated by CHF (pneumonia group) and 28 healthy children (control group).Serum levels of FABP and BNP in the pneumonia group at the acute stage were significantly higher than those in the control group and those at the recovery stage (P0.01). Compared with the control group, serum levels of FABP and BNP in the pneumonia group at the recovery stage increased significantly (P0.01). At the acute stage, 35 patients (97.2%) showed increased serum FABP level but 28 (77.8%) showed increased serum BNP level (P0.05) in the pneumonia group. At the recovery stage, the incidence of abnormal serum FABP (72.2%) was significantly higher than that of BNP (44.4%) in the pneumonia group (P0.05).Serum levels of FABP and BNP can be regarded as biochemical markers of myocardial damage in children with pneumonia complicated by CHF and serum FABP appears to be a more sensitive one. Serum FABP and BNP remained at higher levels through the recovery stage, suggesting that myocardial damage existed though the clinical symptoms were improved at the stage.

This study examined serum level of heart-type fatty acid-binding protein (h-FABP) in children with Kawasaki disease (KD) in order to assess its value in KD.Forty children with KD and 30 healthy children were enrolled. Serum levels of h-FABP and cardiac troponin I (cTnI) were measured using ELISA. Serum creatine kinase-MB (CK-MB) level was detected using an autoanalyer. The KD group was classified into two subgroups, with or without coronary artery lesions, based on the findings of the echocardiography.Mean serum levels of h-FABP (18.17+/-13.38 ng/mL vs 6.25+/-1.70 ng/mL; P0.01) and cTnI (0.27+/-0.22 ng/mL vs 0.11+/-0.02 ng/mL; P0.05) in the KD group was significantly higher than those in the control group. There was no significant difference in serum CK-MB concentrations between the two groups. Twenty-six patients (65%) and eight patients (20%) showed abnormally increased h-FABP and cTnI levels respectively in the KD group, but none of the control group showed increased levels of both. In the KD group, the percentage of patients with increased h-FABP was significantly higher than those with increased CTnI (P0.01). The patients with coronary artery lesions had higher serum h-FABP level than those without (28.14+/-14.26 ng/mL vs 11.52+/-6.28 ng/mL; P0.01).Serum levels of h-FABP and cTnI increase and can be used as the biomarkers of myocardial damage in children with KD. h-FABP appears to be more sensitive and specific. Detection of serum h-FABP level is useful for diagnosis of KD and coronary artery lesions secondary to KD.

The structures formed on the Ni(100) surface during oxygen adsorption, leading to oxidation, are studied with Video-LEED (low-energy electron diffraction) and AES (Auger electron spectroscopy). The temperature- and exposure-dependence in the development of LEED patterns observed during oxidation of Ni(100), at oxidation temperatures of 80 to 400 K, are investigated extensively. Integrated diffraction spot intensities and fractional spot profiles are measured quantitatively and continuously, allowing unambiguous correlation of various surface processes. AES is used to measure the oxidation onset during adsorption and the final relative thickness of the oxide. 48 figs., 79 refs.