Active and Passive Factors of Oil Prices

Price volatility analysis is a basic problem in the price modification,financial risk estimation and management process.Among the global commodities,oil plays an important role in the development of modern industry and economy.Hence the price of crude oil analysis is a hot topic.It is also a difficult topic since there are so many factors associating the price volatilities.And some factors give the different influences in the different periods.Based on data computing,people generally classify the factors into positive and negative ones.But some factors do not affect the price as the nominal effect.For instance,the output of OPEC gave the positive contributions to the oil price in the past long time.Hence,the investigation of the historic WTI oil price is well proposed and the factors are classified into active and passive ones.And then the better explanations are given using this type of classification.

Performance Evaluation of a Permanent Magnet Electric-Drive- Reconfigured Onboard Charger with Active Power Factor Correction

This paper presents a comprehensive charging operation for an electric-drive-reconfigured onboard charger(EDROC)with active power factor correction(APFC).The charging topology exclusively utilizes the three-phase permanent magnet synchronous motor(PMSM)propulsion system as a three-channel boost-type converter in which only a contactor and a small diode bridge are added.First,the operation scenario of the EDROC is introduced.Second,the relationship between electromagnetic torque and rotor position is investigated.Third,the current ripple cancellation of the EDROC is discussed in detail.Moreover,to implement the single-phase APFC along with charging voltage/current regulation of propulsion battery,control strategies including current balancing and synchronous/interleaving PWM strategies are incorporated.Finally,200W proof-of-concept prototype-based tests are conducted under different operation scenarios.

ISOTHERMAL EFFECTIVENESS FACTORS FOR NONUNIFORM ACTIVE CATALYST

Isothermal effectiveness factors for slab,cylinder and sphere shaped catalysts with uniform or nonuni-form intrinsic activity profiles have been investigated.In the case of zero-,first- and second-order kinetics,the effectiveness factors of pellets with increasing activity towards the pellet surface are larger than that ofuniform active catalyst,and they are proportional to the square root of the activity at the pellet surfacewith significant diffusion effect.The effectiveness factor-Thiele modulus curves which are valid for bothuniform and nonuniform catalysts have been obtained with the Thiele modulus modified by equivalent thick-hess of effective layer of the catalyst.Thus,the effectiveness factor for nonuniform active catalyst could bepredicted with a maximun deviation of 5% in the case of significant or insignificant diffusion effect but 10%in general.

Integrated analyses of transcriptomics and network pharmacology reveal leukocyte characteristics and functional changes in subthreshold depression,elucidating the curative mechanism of Danzhi Xiaoyao powder

Objective:To investigate the molecular mechanism and identify potential drugs for subthreshold depression(SD),and elucidate the detalied mechanism of Danzhi Xiaoyao powder(DZXY)in SD.Methods:Using RNA-sequencing,we identified differentially expressed genes(DEGs)in leukocytes of SD compared to healthy controls,deciphered their functions and pathways,and identified the hub genes of SD.We also assessed changes in leukocyte transcription factor activity in patients with SD using the TELis platform.The Connectivity Map database was retrieved to screen candidate drugs for SD.Based on network pharmacology,we elucidated the"multi-component,multi-target,and multi-pathway"mechanism of DZXY in the treatment of SD.Results:We identified 1080 DEGs(padj<0.05 and|log2(fold change)l≥1&protein coding)in the leukocytes of patients with SD.These DEGs,including hub genes,were primarily involved in immune and inflammatory response-related processes.Transcription factor activity analysis revealed similarities between the leukocyte transcriptome profile in SD and the conserved transcriptional response to adversities in immune cells.Connectivity Map analysis identified 28 potential drugs for SD treatment,particularly SB-202190 and TWS-119.Constructing the"Direct Compounds-Direct Targets-Pathways"network for DZXY and SD revealed the curative mechanisms of DZXY in SD,primarily including inflammatory response,lipid metabolism,immune response,and other processes.Conclusion:These results provide new insights into the characteristics and functional changes of leukocytes in SD,partially illustrate the pathogenesis of SD,and suggest potential drugs for SD.The curative mechanisms of DZXY in SD are also partially elucidated.

Cav3.2 channel regulates cerebral ischemia/reperfusion injury:a promising target for intervention

Calcium influx into neurons triggers neuronal death during cerebral ischemia/reperfusion injury.Various calcium channels are involved in cerebral ischemia/reperfusion injury.Cav3.2 channel is a main subtype of T-type calcium channels.T-type calcium channel blockers,such as pimozide and mibefradil,have been shown to prevent cerebral ischemia/reperfusion injury-induced brain injury.However,the role of Cav3.2 channels in cerebral ischemia/reperfusion injury remains unclear.Here,in vitro and in vivo models of cerebral ischemia/reperfusion injury were established using middle cerebral artery occlusion in mice and high glucose hypoxia/reoxygenation exposure in primary hippocampal neurons.The results showed that Cav3.2 expression was significantly upregulated in injured hippocampal tissue and primary hippocampal neurons.We further established a Cav3.2 gene-knockout mouse model of cerebral ischemia/reperfusion injury.Cav3.2 knockout markedly reduced infarct volume and brain water content,and alleviated neurological dysfunction after cerebral ischemia/reperfusion injury.Additionally,Cav3.2 knockout attenuated cerebral ischemia/reperfusion injury-induced oxidative stress,inflammatory response,and neuronal apoptosis.In the hippocampus of Cav3.2-knockout mice,calcineurin overexpression offset the beneficial effect of Cav3.2 knockout after cerebral ischemia/reperfusion injury.These findings suggest that the neuroprotective function of Cav3.2 knockout is mediated by calcineurin/nuclear factor of activated T cells 3 signaling.Findings from this study suggest that Cav3.2 could be a promising target for treatment of cerebral ischemia/reperfusion injury.

Elevated Platelet Activating Factor Level in Ischemia-Related Arrhythmia and Its Electrophysiological Effect on Myocardium

Objective The mechanism through which platelet activating factor （PAF） induces cardiac electrical activity and arrhythmia is not well understood and previous studies have suggested a potential involvement of ion channels in its action. The present study was aimed to clarify the role of PAF in fatal arrhythmias following acute myocardia infarction （AMI） and the underlying mechanism. Methods （1） Blood PAF levels were measured among 72 AMI patients at the time of diagnosis with AMI and 48 h later, and their electrocardiogram （ECG） was recorded continuously. （2） Ischemia simulation and surface electrocardiogram were conducted in 20 pigs and their PAF levels were measured. （3） PAF perfusion and standard microelectrode recording were performed on guinea pig papillarymuscles. Results In both humans and pigs, elevated PAF levels were detected in AMI and simulated ischemia, respectively, and even higher PAF levels were found when fatal arrhythmias occurred. In guinea pig myocardium, PAF induced a shortening of action potential duration at 90% level of repolarization （APD 90 ）under non-ischemic conditions and a more pronounced shortening under early simulated ischemic conditions. Conclusion AMI and ischemia are associated with increased PAF levels in humans and pigs, which are further raised when fatal arrhythmia follows. The effects of PAF on the myocardium may be mediated by multiple ion channels.

Sequential expression of cyclooxygenase-2, glutamate receptor-2, and platelet activating factor receptor in rat hippocampal neurons after fluid percussion injury

Traumatic brain injury causes gene expression changes in different brain regions. Occurrence and development of traumatic brain injury are closely related, involving expression of three factors, namely cyclooxygenase-2, glutamate receptor-2, and platelet activating factor receptor. However, little is known about the correlation of these three factors and brain neuronal injury. In this study, primary cultured rat hippocampal neurons were subjected to fluid percussion injury according to Scott’s method, with some modifications. RT-PCR and semi-quantitative immunocytochemical staining was used to measure the expression levels of cyclooxygenase-2, glutamate receptor-2, and platelet activating factor receptor. Our results found that cyclooxygenase-2 expression were firstly increased post-injury, and then decreased. Both mRNA and protein expression levels reached peaks at 8 and 12 hours post-injury, respectively. Similar sequential changes in glutamate receptor 2 were observed, with highest levels mRNA and protein expression at 8 and 12 hours post-injury respectively. On the contrary, the expressions of platelet activating factor receptor were firstly decreased post-injury, and then increased. Both mRNA and protein expression levels reached the lowest levels at 8 and 12 hours post-injury, respectively. Totally, our findings suggest that these three factors are involved in occurrence and development of hippocampal neuronal injury.

Qingyi decoction attenuates intestinal epithelial cell injury via the calcineurin/nuclear factor of activated T-cells pathway

BACKGROUND Recent studies have demonstrated that dysfunction of the intestinal barrier is a significant contributing factor to the development of severe acute pancreatitis(SAP).A stable intestinal mucosa barrier functions as a major anatomic and functional barrier,owing to the balance between intestinal epithelial cell(IEC)proliferation and apoptosis.There is some evidence that calcium overload may trigger IEC apoptosis and that calcineurin(CaN)/nuclear factor of activated Tcells(NFAT)signaling might play an important role in calcium-mediated apoptosis.AIM To investigate the potential mechanisms underlying the therapeutic effect of Qingyi decoction(QYD)in SAP.METHODS A rat model of SAP was created via retrograde infusion of sodium deoxycholate.Serum levels of amylase,tumor necrosis factor(TNF-α),interleukin(IL)-6,D-lactic acid,and diamine oxidase(DAO);histological changes;and apoptosis of IECs were examined in rats with or without QYD treatment.The expression of the two subunits of CaN and NFAT in intestinal tissue was measured via quantitative realtime polymerase chain reaction and western blotting.For in vitro studies,Caco-2 cells were treated with lipopolysaccharide(LPS)and QYD serum,and then cell viability and intracellular calcium levels were detected.RESULTS Retrograde infusion of sodium deoxycholate increased the severity of pancreatic and intestinal pathology and the levels of serum amylase,TNF-α,and IL-6.Both the indicators of intestinal mucosa damage(D-lactic acid and DAO)and the levels of IEC apoptosis were elevated in the SAP group.QYD treatment reduced the serum levels of amylase,TNF-α,IL-6,D-lactic acid,and DAO and attenuated the histological findings.IEC apoptosis associated with SAP was ameliorated under QYD treatment.In addition,the protein expression levels of the two subunits of CaN were remarkably elevated in the SAP group,and the NFATc3 gene was significantly upregulated at both the transcript and protein levels in the SAP group compared with the control group.QYD significantly restrained CaN and NFATc3 gene expression in the intestine,which was upregulated in the SAP group.Furthermore,QYD serum significantly decreased the LPS-induced elevation in intracellular free Ca^(2+)levels and inhibited cell death.CONCLUSION QYD can exert protective effects against intestinal mucosa damage caused by SAP and the protective effects are mediated,at least partially,by restraining IEC apoptosis via the CaN/NFATc3 pathway.

The hypoxia-inducible factor-1α activates ectopic production of fibroblast growth factor 23 in tumor-induced osteomalacia

Tumor-induced osteomalacia （TIO） is a rare paraneoplastic syndrome in which ectopic production of fibroblast growth factor 23 （FGF23） by non-malignant mesenchymal tumors causes phosphate wasting and bone fractures. Recent studies have implicated the hypoxia-inducible factor-la （HIF-la） in other phosphate wasting disorders caused by elevated FGF23, including X-linked hypophosphatemic rickets and autosomal dominant hypophosphatemia. Here we provide evidence that HIF-la mediates aberrant FGF23 in TIO by transcriptionally activating its promoter. Immunohistochemical studies in phosphaturic mesenchymal tumors resected from patients with documented TIO showed that HIF-la and FGF23 were co-localized in spindle- shaped cells adjacent to blood vessels. Cultured tumor tissue produced high levels of intact FGF23 and demonstrated increased expression of HIF-la protein. Transfection of MC3T3-E1 and Saos-2 cells with a HIF-la expression construct induced the activity of a FGF23 reporter construct. Prior treatment of tumor organ cultures with HIF-la inhibitors decreased HIF-la and FGF23 protein accumulation and inhibited HIF-la-induced luciferase reporter activity in transfected cells. Chromatin immunoprecipitation assays confirmed binding to a HIF-la consensus sequence within the proximal FGF23 promoter, which was eliminated by treatment with a HIF-la inhibitor. These results show for the first time that HIF-la is a direct transcriptional activator of FGF23 and suggest that upregulation of HIF-la activity in TIO contributes to the aberrant FGF23 production in these patients.

When and how does brain-derived neurotrophic factor activate Nrf2 in astrocytes and neurons？

Circadian rhythm protects neurons：Although the master clock entrains the whole body rhythm,peripheral tissues also express core clock transcription factors Clock and Bmal1,which regulate expression of clock genes including Period（Per）and Cryptochrome（Cry）proteins.Complexes of Per and Cry proteins repress Bmal1-and Clock-mediated transcription forming a negative feedback loop,which regulates nearly a 24 hours self-sustained rhythm including energy metabolism.

In vitro effects of buyang huanwu decoction and its ingredients on inhibiting the specific binding of ~3H-platelet activating factor to its receptor in rabbits

BACKGROUND： Pharmacologic action of traditional Chinese medicine compound is the comprehensive effect of various ingredients, and the interactions of various ingredients are closely correlated with the final effect. In order to reveal the compatibility mechanism of buyang huanwu decoction （BHD）＇s prescription in treating and preventing ischemic cerebrovascular disease, we need to explore the effect and relation of ingredients in prescription except for considering the effect of each ingredient on the whole prescription. OBJECTIVE： To study the effect of BHD and its ingredients in the prescription on the specific binding of 3H-platelet activating factor （PAF） to its receptor （PAFR）in rabbits in vitro, and to analyze the action of each ingredient in the prescription. DESIGN： A decomposed recipe study based on orthogonal test. SETTING： Guangzhou University of Traditional Chinese Medicine. MATERIALS： Five healthy adult New Zealand rabbits of either gender were provided by the Experimental Animal Center of Guangzhou University of Traditional Chinese medicine. The prescription herbal pieces were purchased from Foshan Kangpu Pharmaceuticals Company and Jianmin Pharmaceuticals Company, and were appraised by Professor Yanchen Xu from College of Traditional Chinese Medicine, Guangzhou University of Traditional Chinese Medicine. 3H-PAF was supplied by Amersham Co,Ltd.（Specific activity： 6.475 TBq/mmol;batch number：200402）; PAF standard by Biomol Co., Ltd.（batch number： P1318V）. METHODS： This experiment was carried out in the Laboratory of Nuclear Medicine, Guangzhou University of Traditional Chinese Medicine between September and December 2004. ①The seven influencing factors were selected： such as Shenghuangqi , Dangguiwei, Chishao, Dilong, Taoren, Honghua, Chuanxiong. Each factor was divided into two levels, selected or not selected. The tests were arranged according to L8 （27） orthogonal test table. ②The specific binding of 3H-PAF to its receptors in rabbits was measured by radioligand binding assay. The inhibitory rate of the specific binding was used as an assessing index. The inhibitory action of and on 3H-PAF to PAFR binding was analyzed and compared in vitro. The inhibitory action of each ingredient in the prescription BHD on 3H-PAF to PAFR binding was investigated and compared in vitro by direct analysis and analysis of variance of orthogonal test. MAIN OUTCOME MEASURES： Effect of 8 prescriptions for L8 （27） orthogonal test table on the specific binding inhibition rate of 3H-PAF and PAFR. RESULTS： According to results of variance analysis of orthogonal test, the inhibitory action of each ingredient in the prescription BHD on 3H-PAF to PAFR binding from the highest to the lowest was in turn Honghua, ShenghuangqL Taoren, Dilong, DangguiweL Chuanxiong, Chishao. Honghua, Shenghuangqi, Taoren, Dilong, Danguiwei were major influence factors to 3H-PAF to PAFR in rabbits （F = 187.829,144.446,59.521,5.018,4.265, P 〈 0.05- 0.01）, but Chuanxiong and Chishao had not obviously inhibitory effect. The specific binding inhibition rate of prescriptions （except Shenghuangqi ） was obviously higher than that of one of prescriptions （Shenghuangqi included）. CONCLUSION： The results of orthogonal test show that Honghua, ShenghuangqL Taoren, Dilong, Dangguiwei are major influencing factors to inhibit binding of sH-PAF to PAFR in rabbits, among which, Honghua is the strongest in ingredients of prescription BHD. The results also reveal that Shenghuangqi is able to weaken the inhibitory effect and to prevent the strong inhibitory effect of blood-activating drugs in BHD.

Recombinant-activated factorⅦand neuronal apoptosis in a rat model of intracerebral hemorrhage

BACKGROUND： Activated clotting factor VII has been demonstrated to exhibit obvious anti-apoptosis effects. OBJECTIVE： To observe the effect of activated clotting factor VII on neuronal apoptosis at different time points following rat intracerebral hemorrhage （ICH）. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Neurobiological Laboratory of Second Military Medical University from October 2005 to April 2006. MATERIALS： Recombinant-activated clotting factor Vlla （rFVtla） was purchased from Danish Novo Nordisk, Denmark. In situ cell death detection kit-POD kit was purchased from Roche, Switzerland. Caspase-3 activity determination kit from Biovision, USA. METHODS： A total of 72 healthy, male, Sprague Dawley rats, aged 5-8 months, were randomly assigned to three groups （n = 24）： sham-operated, ICH model, and rFVIla. In the ICH model and rFVIla groups, 80.0μL autologous non-clotting blood from rat tails was injected into the right caudate putamen to establish the ICH. The empty microinjector was inserted into the caudate putamen in the sham-operated group. The ICH model and rFVIla groups were subdivided into four subsets separately： 6, 24, 72 hours and 7 days following ICH. The rats in the rFVIla group were injected with 160 μg/kg rFVIla via the dorsal vein of the penis. MAIN OUTCOME MEASURES： Apoptotic cells were detected in the right caudate putamen by TUNEL; caspase-3 activity by spectrophotometry; and rat neurological function was evaluated by neurological functional impairment scales. RESULTS： Rat neurological function was deteriorated at 24, 72 hours, and 7 days following ICH. The TUNEL-positive cells and caspase-3 activity in the right caudate putamen was significantly increased in the ICH rats （P 〈 0.05）; rFVlla treatment reduced the number of TUNEL-positive cells and caspase-3 activity in the right caudate putamen （P 〈 0.05）, and neurological function was significantly improved （P 〈 0.05）. CONCLUSION： rFVIla was applied within 72 hours after tCH, which reduced the amount of neuronal apoptosis and promoted neurological function restoration by possibly inhibiting caspase-3 activity.

Effects of Buyang Huanwu decoction and Astragalus mongholicus on platelet activating factor receptor activity in rabbits in vitro

BACKGROUND: The pharmacological action of traditional Chinese medicine compound is the comprehensive effect of the various ingredients, and the interactions of various ingredients are closely correlated with the final effect. In order to reveal the compatibility mechanism of BHD's prescription in treating and preventing ischemic cerebrovascular disease, we needed explore the effect and relation of ingredients in the prescription. OBJECTIVE: To observe the effect of Buyang Huanwu decoction (BHD) and Astragalus mongholicus on the activity of platelet activating factor receptor (PAFR) in the platelet of rabbits in vitro, and investigate the mechanism of Astragalus mongholicus. DESIGN: A decomposed recipes study. SETTING: Guangzhou University of Traditional Chinese Medicine. MATERIALS: Five New Zealand rabbits, weighing 2-3 kg, both sexes, were used. BHD was composed of Sheng Huang Qi 120 g, Dang Gui Wei 6 g, Chi Shao 4.5 g, Chuan Xiong 3 g, Di Long 3 g, Tao Ren 3 g, Hong Hua 3 g. The prescription for activating blood circulation consisted of Dang Gui Wei 6 g, Chi Shao 4.5 g, Chuan Xiong 3 g, Di Long 3 g, Tao Ren 3 g and Hong Hua 3 g. The prescription for invigorating qi consisted of 120 g Sheng Huang Qi. The prepared herbal pieces were purchased from the traditional Chinese medicine Dispensary of Foshan Second People's Hospital, and appraised by Professor Xu from Science of Chinese Materia Medica College, Guangzhou University of Traditional Chinese Medicine. 3H-PAF was supplied by Amersham Co., Ltd. (specific activity: 6. 475 TBq/mmol; batch number: 200402); PAF standard by Biomol Co., Ltd. (batch number: P1318V). METHODS: The experiments were carried out in the Laboratory of Nuclear Medicine, Guangzhou University of Traditional Chinese Medicine from September to December 2004. ① Injections of BHD, prescriptions for activating blood circulation and invigorating qi were prepared by the decoction and alcohol sedimentation technique. Rabbit common carotid artery blood (40 mL) was drawn via intubation to prepare platelet suspension of (0.8-1.0)×1010 L-1. ② Determination of 3H-PAF and washed PAFR binding: The general combination tube (T) contained washed platelet-rich plasma (WPRP) 380 μL + 3H-PAF (0.35 nmol/L)10 μL+distilled water 5 μL; The nonspecific binding tube (P) contained WPRP 380 μL+3H-PAF(0.35 nmol/L)10 μL+cold PAF (1 μmol/L) 5 μL; The sample tube (Y) contained WPRP 380 μL+3H-PAF(0.35 nmol/L)10 μL+experimental medicine (injection of BHD, prescriptions for activating blood circulation or invigorating qi) 5 μL. The test was conducted for three times for each sample in the same way as mentioned above. The samples were shaken on the oscillator for 30 s, then bathed at 25 ℃ for 40 minutes, and the reaction was terminated with cold Tris buffer containing 0.1% BSA, multichannel cell detachment separator was used for vacuum suction to filter the separated free 3H-PAF, and the filter paper was washed with cold Tris buffer for four times, then dried in the baking oven (80 ℃) for 1 hour, and placed in xylol liquid scintillator, and the radioactivity was determined automatically by the liquid scintillation detector. The mean of the three parallel tubes was calculated. The specific binging inhibition rate was calculated: SBIR=[(T-Y)/(T-P)]×100%]. ③ Univariate analysis of variance was conducted. And for comparison of each paired groups, the q test was adopted. MAIN OUTCOME MEASURES: Effect of BHD whole prescription, prescriptions for activating blood circulation and invigorating qi on the specific binding inhibition rate of 3H-PAF and PAFR. RESULTS: BHD, prescriptions for activating blood circulation and invigorating qi were all able to inhibit the specific binding of 3H-PAF to PAFR, the specific blinding inhibition rates were (45.90±7.50)%, (97.90±1.84)% and (26.75±2.48)%, respectively, and there were significant differences between every two groups (P < 0.01). CONCLUSION: Single Astragalus mongholicus (120 g) can inhibit the specific blinding of PAFR in the platelet of the rabbit with 3H-PAF, but the combination of Astragalus mongholicus with the drugs for activating blood circulation in BHD can significantly decrease the inhibiting action of the latter on PAFR activity of the platelet, reflecting the combined mechanism of 'removing blood stasis without injuring the vital qi' in BHD.

CONDITIONED MEDIUM OF HUMAN NASOPHARYNGEAL CARCINOMA EPITHELIOID CELL LINE CNE_(1) CONTAINED THE ACTIVITIES OF TRANSFORMED GROWTH-INHIBITING FACTORS

The hormone defined serum free conditioned medium (SFCM) of human nasopharyngeal carcinoma epithelioid cell line (CNE1) was assayed by both the 3H-thymidine incorporation test and the soft agar test. It was found that the SFCM stimulated the growth of long-term serum-free cultured CNE4 cells in ac-cordence with the fact that the growth rate of long-term serum-free cultured CNE1 cells was directly proportional to the plating density. Alternatively 5% SFCM inhibited the growth of short-term serum-free cultured CNE4 cells by 51% in which the indicator cell remained the responsiveness state of growing in the serum-supplemented medium to the effector of interest. Furthermore, SFCM resulted in the inhibition of anchorage-independent growth of CNE4 cells and A431 cells. Also in soft agar test. SFCM reduced the colony formation of NRK(?),9F cells in the presence of EGF or EGF plus TGF-β. These finding suggested that CNE4 secreted autocrine growth stimulating factor(s) and growth inhibiting factor(s) in the serum-free medium, the latter strongly reverse malignant phenotypes of CNE4 and A431 cells in serum-supplemented surrounding.

Activation of epidermal growth factor receptor mediates myocardial ischemia/reperfusion arrhythmias in anaesthetized rats

Objectives Epidermal growth factor receptor （EGFR）is a receptor protein tyrosine kinase and plays a critical role in the development and function of the heart.Previous studies have demonstrated that EGFR is involved in regulating electrical excitability of the heart.The present study was designed to investigate whether EGFR activation would mediate myocardial arrhythmias induced by ischemia/reperfu- sion in anaesthetized rats.Methods and results Myocardial ischemia/reperfusion arrhythmias were induced by 10 min ligation of the left anterior descending coronary artery,followed by a 30 min reperfusion in anaesthetized rats.Incidence and severity of cardiac arrhythmias were significantly reduced by pretreatment with the EGFR kinase inhibitor AG556.Phosphorylation level of myocardial EGFR was increased during ischemia and at early reperfusion.Intramyocardial transfection of EGFR siRNA reduced EGFR mRNA and protein,and decreased the incidence of ventricular fibrillation induced by reperfusion.Interestingly,tyrosine phosphorylation levels of cardiac Na+ channel(INa) and L-type Ca2+ channel(ICa.l) were significantly increased at corresponding time points to the alteration of phosphorylated EGFR level during reperfusion.AG556 pretreatment countered the increased tyrosine phosphorylation level of Na+ and L-type Ca2+ channels induced by reperfusion.No significant alteration was observed in tyrosine phosphorylation levels of cardiac Kv4.2 and Kir2.1 channels during the cardiac ischemia/reperfusion. Conclusions These results demonstrate for the first time that EGFR plays an important role in the genesis of myocardial ischemia/reperfusion arrhythmias,which is likely mediated at least in part by enhancing tyrosine phosphorylation of cardiac Na+ and L-type Ca2+ channels.

Inhibiting 5-hydroxytryptamine receptor 3 alleviates pathological changes of a mouse model of Alzheimer's disease

Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In this study,we found that 5-hydroxytryptamin receptor 3A subunit(HTR3A) was highly expressed in the brain tissue of transgenic amyloid precursor protein and presenilin-1 mice(an Alzheimer’s disease model) and patients with Alzheimer’s disease.To investigate whether HTR3A-positive interneurons are associated with the production of Aβ plaques,we performed double immunostaining and found that HTR3A-positive interneurons were clustered around Aβ plaques in the mouse model.Some amyloid precursor protein-positive or β-site amyloid precursor protein cleaving enzyme-1-positive neurites near Aβ plaques were co-localized with HTR3A interneurons.These results suggest that HTR3A-positive interneurons may partially contribute to the generation of Aβ peptides.We treated 5.0-5.5-month-old model mice with tro pisetron,a HTR3 antagonist,for 8 consecutive weeks.We found that the cognitive deficit of mice was partially reversed,Aβ plaques and neuroinflammation we re remarkably reduced,the expression of HTR3 was remarkably decreased and the calcineurin/nuclear factor of activated T-cell 4 signaling pathway was inhibited in treated model mice.These findings suggest that HTR3A interneurons partly contribute to generation of Aβ peptide at the initial stage of Alzheimer’s disease and inhibiting HTR3 partly reve rses the pathological changes of Alzheimer’s disease.

The Role and Mechanism of Unfolded Protein Response Pathway in Tumor Drug Resistance

In the process of tumor proliferation and metastasis,tumor cells encounter hypoxia,low glucose,acidosis,and other stressful environments.These conditions prompt tumor cells to generate endoplasmic reticulum stress(ERS).As a signal mechanism that mitigates ERS in eukaryotic cells,the unfolded protein response(UPR)pathway can activate cells and tissues,regulating pathological activities in various cells,and maintaining ER homeostasis.It forms the most crucial adaptive and defensive mechanism for cells.However,under the continuous influence of chemotherapy drugs,the quantity of unfolded proteins and erroneous proteins produced by tumor cells significantly increases,surpassing the normal regulatory range of UPR.Consequently,ERS fails to function properly,fostering tumor cell proliferation and the development of drug resistance.This review delves into the study of three UPR pathways(PERK,IRE1,and ATF6),elucidating the mechanisms of drug resistance and research progress in the signal transduction pathway of UPR related to cancers.It provides a profound understanding of the role and relationship between UPR and anti-tumor drugs,offering a new direction for effective clinical treatment.

Interleukin-1βinduces human cementoblasts to support osteoclastogenesis

Injury of the periodontium followed by inflammatory response often leads to mot resorption. Resorption is accomplished by osteoclasts and their generation may depend on an interaction with the cells in direct contact with the root, the cementoblasts. Our study aimed to investigate the role of human cementoblasts in the formation of osteoclasts and the effect of interleukin （IL）- 1β hereupon. Extracted teeth from healthy volunteers were subjected to sequential digestion by type I collagenase and trypsin. The effect of enzymatic digestion on the presence of cells on the root surface was analyzed by histology. Gene expression of primary human cementoblasts （pHCB） was compared with a human cementoblast cell line （HCEM）. The pHCBs were analyzed for their expression of IL-1 receptors as well as of receptor activator of nuclear factor kappa-B ligand （RANKL） and osteoprotegerin （OPG）. In a co-culture system consisting of osteoclast precursors （blood monocytes） and pHCBs, the formation of osteoclasts and their resorptive activity was assessed by osteo-assay and ivory slices. The cells obtained after a 120 min enzyme digestion expressed the highest level of bone sialoprotein, similar to that of HCEM. This fraction of isolated cells also shared a similar expression pattern of IL-1 receptors （ILl-R1 and ILl-R2）. Treatment with IL-11~ potently upregulated RANKL expression but not of OPG. pHCBs were shown to induce the formation of functional osteoclasts. This capacity was significantly stimulated by pretreating the pHCBs with IL-1β prior to their co-culture with human blood monocytes. Our study demonstrated that cementoblasts have the capacity to induce osteoclastogenesis, a capacity strongly promoted by IL-1β. These results may explain why osteoclasts can be formed next to the root of teeth.

Endoplasmic reticulum stress transducer old astrocyte specifically induced substance contributes to astrogliosis after spinal cord injury

Old astrocyte specifically induced substance （OASIS） is an endoplasmic reticulum （ER） stress transducer specifically expressed in astrocytes and osteoblasts. OASIS regulates the differentiation of neural precursor cells into astrocytes in the central nervous system. This study aimed to elucidate the involvement of ER stress responses stimulated via OASIS in astrogliosis following spinal cord injury. In a mouse model of spinal cord contusion injury, OASIS mRNA and protein expression were evaluated at days 7 and 14. A significant increase in OASIS mRNA on day 7 and an increase in protein on days 7 and 14 was observed in injured spinal cords. Immunostaining on day 7 revealed co-localization of OASIS and astrocytes in the periphery of the injury site. Furthermore, anti-OASIS small interfering RNA （siRNA） was injected at the injury sites on day 5 to elucidate the function of OASIS. Treatment with anti-OASIS siRNA caused a significant decrease in OASIS mRNA on day 7 and protein on days 7 and 14, and was associated with the inhibition of astrogliosis and hindlimb motor function recovery. Results of our study show that OASIS expression synchronizes with astrogliosis and is functionally associated with astrogliosis after spinal cord injury.

NFAT2 is implicated in corticosterone-induced rat Leydig cell apoptosis

Aim： To investigate the activation of the nuclear factor of activated T cells （NFAT） and its function in the corticosterone （CORT）-induced apoptosis of rat Leydig cells. Methods： NFAT in rat Leydig cells was detected by Western blotting and immunohistochemical staining. Cyclosporin A （CsA） was used to evaluate potential involvement of NFAT in the CORT-induced apoptosis of Leydig cells. Intracellular Ca^2＋ was monitored in CORT-treated Leydig cells using Fluo-3/AM. After the Leydig cells were incubated with either CORT or CORT plus CsA for 12 h, the levels of NFAT2 in the nuclei and in the cytoplasm were measured by semi-quantitative Western blotting. The role of NFAT2 in CORT- induced Leydig cell apoptosis was further evaluated by observing the effects of NFAT2 overexpression and the inhibition of NFAT2 activation by CsA on FasL expression and apoptosis. Results： We found that NFAT2 was the predominant isoform in Leydig cells. CsA blocked the CORT-induced apoptosis of the Leydig cells. The intracellular Ca^2＋ level in the Leydig cells was significantly increased after the CORT treatment. The CORT increased the level of NFAT2 in the nuclei and decreased its level in the cytoplasm. CsA blocked the CORT-induced nuclear translocation of NFAT2 in the Leydig cells. Both CORT-induced apoptosis and FasL expression in the rat Leydig cells were enhanced by the overexpression of NFAT2 and antagonized by CsA. Conclusion： NFAT2 was activated in CORT-induced Leydig cell apoptosis. The effects of NFAT2 overexpression and the inhibition of NFAT2 activation suggest that NFAT2 may potentially play a pro-apoptotic role in CORT-induced Leydig cell apoptosis through the up-regulation of FasL.