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"Chen, Xiao Chu"
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Central neuromechanisms underlying control of intragastric pressure through acupuncture at Zusanli（ST36） in rats： the upper cervical cord is the key link between the ascending and descending pathways
Sensory inputs stimulated by Zusanli（ST36） acupuncture in the abdomen are known to converge in the upper cervical cord. However, it is unclear whether these inputs are subsequently conveyed to the hypothalamic paraventricular nucleus and what kind of afferent fibers are involved. We focused on the upper cervical cord, where afferent inputs converge, and detected c-fos expression in oxytocinergic neurons. We found that Zusanli acupuncture therapy effectively elevated intragastric pressure, but inhibited expression of c-fos in oxytocinergic neurons of the paraventricular nucleus in upper cervical cord injured rats. These Zusanli acupuncture effects remained even after complete dorsal cord transection. However, after complete transection of the spinal cord or dorsolateral funiculus, the effects were significantly attenuated and even disappeared. These findings suggest that the paraventricular nucleus is responsible for pooling and integrating signals from the Zusanli acupuncture and sensory information from the intragastric pressure variation, thereby contributing to the regulation of intragastric pressure. The upper cervical cord serves as the key link between ascending and descending pathways, which conveys afferent inputs to the paraventricular nucleus through the dorsolateral funiculus.
Journal Article
Polypeptide from Chlamys farreri attenuates murine thymocytes damage induced by ultraviolet B
Aim： Polypeptide from Chlamysfarreri （PCF, molecular mass is 879） is a new marine polypeptide compound isolated from Chlamysfarreri. This study investigates the possible protective roles and the mechanism of PCF against ultraviolet B （UVB）-induced apoptosis in murine thymocytes. Methods： The rate of apoptosis and caspase-3 activation was measured by flow cytometry. The expression of stress-response genes c-fos and c-jun was observed by RT-PCR. Western blot analysis was performed to determine the release of cytochrome c. Results： It was found that UVB induced murine thymocyte death. The cells treated with UVB showed an increase in cytochrome c release, caspase-3 activity, as well as in the expression of c-fos and c-jun. In addition, all were involved in UVB-induced cell apoptosis. Conclusion： Our present observations pointed to the ability of PCF to avert UVB-induced apoptosis in thymocytes by modulating c-fos and c-jun expression, cytochrome c release, and the consequent activation of caspase-3, which were essential components of the UV-induced cell apoptotic pathway. The results suggested that PCF is a promising protective substance against UV radiation.
Journal Article
Combined analysis of CRMP4 methylation levels and CAPRA-S score predicts metastasis and outcomes in prostate cancer patients
The present study analyzed the predictive value of combined analysis of collapsin response mediator protein 4 （CRMP4） methylation levels and the Cancer of the Prostate Risk Assessment （CAPRA-S） Postsurgical score of patients who required adjuvant hormone therapy （AHT） after radical prostatectomy （RP）, We retrospectively analyzed 305 patients with prostate cancer （PCa） who received RP and subsequent androgen deprivation therapy （ADT）. Two hundred and thirty patients with clinically high-risk PCa underwent immediate ADT, and 75 patients with intermediate risk PCa underwent deferred ADT. CRMP4 methylation levels in biopsies were determined, and CAPRA-S scores were calculated. In the deferred ADT group, the values of the hazard ratios for tumor progression and cancer-specific mortality （CSM） in patients with 〉15% CRMP4 methylation were 6.81 （95% CI, 2.34-19.80） and 12.83 （95% CI. 2.16-26.10）, respectively. Receiver-operating characteristic curve analysis indicated that CRMP4 methylation levels 〉15% served as a significant prognostic marker of tumor progression and CSM. In the immediate ADT group, CAPRA-S scores ：〉6 and CRMP4 methylation levels ：〉15% were independent predictors of these outcomes （uni- and multi-variable Cox regression analyses）. The differences in the 5-year progression-free survival between each combination were statistically significant. Combining CAPRA-S score and CRMP4 methylation levels improved the area under the curve compared with the CRMP4 or CAPRA-S model. Therefore, CRMP4 methylation levels ：〉15% were significantly associated with a poor prognosis and their combination with CAPRA-S score accurately predicted tumor progression and metastasis for patients requiring AHT after RP.
Journal Article
Effects of thermomechanical treatments on the microstructures and mechanical properties of GTA-welded AZ31B magnesium alloy
Thermomechanical treatments were carried out to improve the properties of AZ31B joints prepared by gas tungsten arc welding. The microstructures of the joints were studied by optical microscopy and scanning electron microscopy with energy-dispersive spectrometry. Tensile tests and hardness tests were performed to investigate the effects of thermomechanical treatments on the mechanical properties of the joints. It is found that the thermomechanical-treated joints show superior mechanical properties against the as-welded joints, and their ultimate tensile strength can reach more than 92% of the base material. This mainly attributes to the formation of fine equiaxed grains in the fusion zone. ARer thermomechanical treatments the dendrites are transformed to fine spherical grains, and the dendritic segregation can be effectively eliminated.
Journal Article
A study on the Dushiling tungsten-copper deposit in the Miao＇ershan-Yuechengling area, Northern Guangxi, China：Implications for variations in the mineralization of multi-aged composite granite plutons
The polymetallic Dushiling W-Cu deposit is a large, altered, skarn-type deposit, located in the northeastern part of the Miao＇ershan-Yuechengling pluton, China. Two types of granite have been identified in the deposit： a medium-grained porphyritic biotite granite, and a medium- to fine-grained biotite granite. Both are spatially and temporally related to ore bodies, suggesting they may be the source of mineralization in the deposit. A medium- to fine-grained porphyritic biotite granite is exposed at the surface in the region of mineralization. U-Pb dating of zircons yielded magmatic ages of 423 Ma for the medium-grained porphyritic biotite granite and 421 Ma for the medium- to fine-grained porphyritic biotite granite, while a younger age（217 Ma） obtained for surface samples indicates later diagenesis. Thus, magmatism occurred during the Caledonian and Indosinian, respectively. The petrological and geochemical characteristics of the two Caledonian granites show that both are calc-alkaline and peraluminous.They are moderately enriched in Cs, Rb, U, and REE, and strongly depleted in Sr,Ba,P,and Ti; they show similar REE behavior,including negative Eu anomalies. These geochemical similarities suggest that the two granites were derived from the same source,although they were emplaced during different stages of the evolution of the magma. Furthermore, the granites are associated with mineralization, suggesting they were the source of mineralization in the Dushiling W-Cu deposit. Sm-Nd ages of scheelite from the Dushiling W-Cu deposit indicate that metallogenesis occurred at 417±35 Ma, while the two types of titanite, intergrown with scheelite, yield U-Pb ages of 423–425 Ma（in altered granite sample） and 218 Ma（in skarn sample）. These ages place the main mineralization event in the late Caledonian, and later magmatic-hydrothermal activity occurred in the Indosinian. The ages obtained for the Dushiling W-Cu deposit in the western Nanling Range, northern Yuechengling, together with the occurrence and ages of the Niutangjie W deposit in southern Yuechengling, provide insight into the process of ore concentration during the Caledonian and Indosinian.
Journal Article
Increased Endogenous Sulfur Dioxide Involved in the Pathogenesis of Postural Tachycardia Syndrome in Children： A Case-Control Study
Background： The pathogenesis of postural tachycardia syndrome （POTS） remains unclear. This study aimed to explore the changes and significance of sulfur dioxide （SO2） in patients with POTS. Methods： The study included 31 children with POTS and 27 healthy children from Peking University First Hospital between December 2013 and October 2015. A detailed medical history, physical examination results, and demographic characteristics were collected. Hemodynamics was recorded and the plasma SO2was determined. Results： The plasma SO2was significantly higher in POTS children compared to healthy children （64.0 ± 20.8 μmol/L vs. 27.2 ± 9.6 μmol/L, respectively, P 〈 0.05）. The symptom scores in POTS were positively correlated with plasma SO2levels （r = 0.398, P 〈 0.05）. In all the study participants, the maximum heart rate （HR） was positively correlated with plasma levels of SO2（r = 0.679, P 〈 0.01）. The change in systolic blood pressure from the supine to upright （ΔSBP） in POTS group was smaller than that in the control group （P 〈 0.05）. The ΔSBP was negatively correlated with baseline plasma SO2levels in all participants （r = ？0.28, P 〈 0.05）. In the control group, ΔSBP was positively correlated with the plasma levels of SO2（r = 0.487, P 〈 0.01）. The change in HR from the supine to upright in POTS was obvious compared to that of the control group. The area under curve was 0.967 （95% confidence interval： 0.928–1.000）, and the cutoff value of plasma SO2level 〉38.17 μmol/L yielded a sensitivity of 90.3% and a specificity of 92.6% for predicting the diagnosis of POTS. Conclusions： Increased endogenous SO2levels might be involved in the pathogenesis of POTS.
Journal Article
Pharmacokinetics and effects of demographic factors on blood 25（OH）D3 levels after a single orally administered high dose of vitamin D3
Aim： To examine the biological consequences and demographic factors that might affect the pharmacokinetics of vitamin D3 after a single high dose intervention in a young Chinese population with vitamin D insufficiency status. Methods： A total of 28 young subjects （25 to 35 years old） with vitamin D insufficiency status [serum 25（OH）D 〈30 ng=mL] was recruited in Shanghai, China. The subjects were orally administered a single high dose of vitamin D3 （300 000 IU）. Baseline characteristics and blood samples were collected at d O, 1, 2, 3, 7, 28, 56, 84 and 112 after the intervention. The blood biomarker levels were determined with standardized methods. Results： The intervention markedly increased the blood 25（OH）D3 levels within the first five days （mean Tmax=5.1±2.1 d） and sustained an optimal circulating level of 25（OH）D3 （〉30 ng/mL） for 56 d. After the intervention, body weight and baseline 25（OH）D3 levels were significantly correlated with circulating 25（OH）D3 levels. No adverse events and no consistently significant changes in serum calcium, creatinine, glucose, parathyroid hormone, vitamin D binding protein, or the urinary calcium/creatinine ratio were observed. However, there was a significant increase in phosphorus after the vitamin D3 intervention. Total cholesterol and triglyceride levels were decreased at the end of the trial. Conclusion： The pharmacokinetics of vitamin D after intervention were influenced by baseline 25（OH）D3 levels and the body weight of the subjects. The results suggest that a single high oral vitamin D3 intervention is safe and efficient for improving the vitamin D status of young Chinese people with vitamin D insufficiency.
Journal Article
Screening possible solid electrolytes by calculating the conduction pathways using Bond Valence method
Inorganic solid electrolytes have distinguished advantages in terms of safety and stability, and are promising to substitute for conventional organic liquid electrolytes. However, low ionic conductivity of typical candidates is the key problem. As connective diffusion path is the prerequisite for high performance, we screen for possible solid electrolytes from the 2004 International Centre for Diffraction Data （ICDD） database by calculating conduction pathways using Bond Valence （BV） method. There are 109846 inorganic crystals in the 2004 ICDD database, and 5295 of them contain lithium. Except for those with toxic, radioactive, rare, or variable valence elements, 1380 materials are candidates for solid electrolytes. The rationality of the BV method is approved by comparing the existing solid electrolytes＇ conduction pathways we had calculated with those from ex- periments or first principle calculations. The implication for doping and substitution, two important ways to improve the conductivity, is also discussed. Among them LizCO3 is selected for a detailed comparison, and the pathway is reproduced well with that based on the density functional studies. To reveal the correlation between connectivity of pathways and conductivity, a/γ-LiAlO2 and Li2CO3 are investigated by the impedance spectrum as an example, and many experimental and theoretical studies are in process to indicate the relationship between property and structure. The BV method can calculate one material within a few minutes, providing an efficient way to lock onto targets from abundant data, and to investigate the struc- ture-property relationship systematically.
Journal Article
Improved peroxidase-mimic property： Sustainable, high- efficiency interfacial catalysis with H2O2 on the surface of vesicles of hexavanadate-organic hybrid surfactants
An emerging method for effectively improving the catalytic activity of metal oxide hybrids involves the creation of metal oxide interfaces for facilitating the activation of reagents. Here, we demonstrate that bilayer vesicles formed from a hexavanadate cluster functionalized with two alkyl chains are highly efficient catalysts for the oxidation of 3,3＇,5,5＇-tetramethylbenzidine （TMB） with H2O2 at room temperature, a widely used model reaction mimicking the activity of peroxidase in biological catalytic oxidation processes. Driven by hydrophobic interactions, the double-tailed hexavanadate-headed amphiphiles can self-assemble into bilayer vesicles and create hydrophobic domains that segregate the TMB chromogenic substrate. The reaction of TMB with H2O2 takes place at the interface of the hydrophilic and hydrophobic domains, where the reagents also make contact with the catalytic hexavanadate clusters, and it is approximately two times more efficient compared with the reactions carried out with the corresponding unassembled systems. Moreover, the assembled vesicular system possesses affinity for TMB comparable to that of reported noble metal mimic nanomaterials, as well as a higher maximum reaction rate.
Journal Article