Objective To investigate the expression of GJB4 gene in pancreatic cancer tissue and its correlation with clinicopathology.Methods The expression levels of GJB4 mRNA in pancreatic cancer and adjacent cancer tissues were analyzed using bioinformatics to analyze the Cancer Genome Atlas(TCGA)and Genotype-Tissue Expression(GTEx)RNA sequencing datasets.A total of 120 pancreatic cancer samples and 40 adjacent cancer samples from the Pathology Department of The Second Affiliated Hospital of Kunming Medical University from January 2019 to December 2023 were collected and sorted.Immunohistochemistry staining method was used to detect the expression difference of GJB4 protein between the two groups.RT-qPCR method was used to detect the expression levels of GJB4 in four pancreatic cancer cell lines.Univariate and multivariate Cox regression and Kaplan-Meier curves were used to analyze the clinical pathological data of GJB4 and pancreatic cancer patients.DAVID functional annotation bioinformatics and GSEA enrichment analysis were used to explore the relevant pathways of GJB4 in pancreatic cancer.Results The expression level of GJB4 mRNA in pancreatic cancer was higher than that in adjacent tissues,and the high expression of GJB4 was significantly associated with poor prognosis of patients(P<0.05).Immunohistochemical analysis showed that GJB4 protein was brown-yellow granular in pancreatic cancer tissues,mainly expressed in cytoplasm and cell membrane,and GJB4 protein expression was up-regulated in pancreatic cancer(P<0.05).The RT-qPCR test results showed that out of 4 pancreatic cancer cell lines,3 of them had upregulated expression(P<0.05).COX regression analysis showed that GJB4 gene was an independent risk factor in the prognosis of pancreatic cancer patients.The results of GO enrichment analysis showed that GJB4 was related to the transmembrane transport,ion channel,signal release and membrane potential regulation of pancreatic cancer.GSEA analysis showed that GJB4 was enriched in the Wnt/β-catenin signaling pathway.Conclusion In pancreatic cancer,the high expression level of GJB4 is closely related to the clinicopathological features of the patients,which may predict the poor prognosis of the patients.GJB4 may be involved in regulating the Wnt/β-catenin signaling pathway of pancreatic cancer,and is expected to be one of the potential biomarkers of pancreatic cancer prognosis.

AIM:To investigate the regulatory role of retinoid X receptor(RXR)in oxidative stress response of rat type Ⅱ alveolar epithelial cells(AECII)induced by hypoxia/reoxygenation(HR).METHODS:The AECII were di-vided into control(C)group,HR group,HR+solvent dimethyl sulfoxide(DMSO)group(HD group),HR+RXR agonist 9-cis-retinoic acid(9-RA)group(RA group),and HR+RXR antagonist HX531 group(HX group).Cell Counting Kit-8(CCK-8)method was used to measure the cell viability.Immunofluorescence staining was used to detect the expression of surfactant protein A(SP-A)and RXRα in AECII.Kits were detected to the levels of superoxide dismutase(SOD)and malondialdehyde(MDA)in cells.Transmission electron microscopy was used to observe the ultrastructural changes of the cells.Western blot was used to detect the protein level of nuclear factor E2-related factor 2(Nrf2).RT-PCR was used to detect the expression level of Nrf2 mRNA.RESULTS:Compared with C group,the cell viability and SOD activity in HR,HD,RA and HX groups were decreased significantly(P<0.05),the MDA content were increased significantly(P<0.05),the Nrf2 mRNA and protein expression levels were decreased significantly(P<0.05 or P<0.01),and the immuno-fluorescence expression of RXRα was significantly increased(P<0.01).Compared with HR and HX groups,the cells in RA group showed significantly increased cell viability(P<0.05),increased SOD activity(P<0.05),decreased MDA con-tent(P<0.05),increased Nrf2 mRNA and protein expression levels(P<0.01),and significantly increased immunofluo-rescence expression of RXRα(P<0.01).CONCLUSION:Hypoxia/reoxygenation can aggravate the oxidative stress re-sponse of rat AECII,and RXR agonist intervention can alleviate HR-induced rat AECII injury by inhibiting oxidative stress.

Objective To identify inflammation-related genes in atrial fibrillation(AF)and explore the possible role and mechanism of these genes and infiltrating immune cells in the development of AF.Methods A series of bioinformatics analysis combined with machine learning algorithms to identify biomarkers of AF,the receiver operating characteristic(ROC)curves were used to verify the prediction and diagnostic value of key genes,and Spearman correlation analysis was used to clarify the correlation between key genes and infiltrating immune cells.Results 593 differential genes(| log2(fold change,FC)|>1,P<0.05),7 immune cell subtypes(P<0.05)were selected,190 immune-related differential genes were obtained,3 biomarkers(IGF1,PTGS 2 and PPARG),and the correlation analysis showed that 3 markers were significantly associated with infiltrating immune cells(P<0.05).Conclusion IGF1,PTGS2 and PPARG are inflammation-related genes of AF,which are speculated to be closely related to the process and pathway of immune cell infiltration.

AIM:To investigate the effects of sodium hydrosulfide(NaHS)on hexokinase 2(HK2)-nucleo-tide-binding oligomerization domain-like receptor protein 3(NLRP3)-gasdermin D(GSDMD)pathway and pyroptosis in-duced by lung ischemia/reperfusion(I/R)in rats.METHODS:Male Sprague-Dawley rats were divided into 6 groups:control group,control+NaHS group,I/R group,low-dose NaHS+I/R(L+I/R)group,medium-dose NaHS+I/R(M+I/R)group,and high-dose NaHS+I/R(H+I/R)group,with 6 rats in each group.The NaHS was administered via intraperi-toneal injection at 1.5 mL,30 min before modeling.The left lung tissues were collected 30 min after ischemia and 1 h af-ter reperfusion,and the wet/dry weight ratio and total lung water content were recorded.Hematoxylin-eosin(HE)staining was used to examine lung tissue morphological changes.The levels of malondialdehyde(MDA),myeloperoxidase(MPO)and lactate in lung tissues were measured with test kits.ELISA was employed to determine the levels of interleukin-1β(IL-1β)and IL-18.The expression of glycolysis-and pyroptosis-related indicators was analyzed by Western blot,qRT-PCR and immunofluorescence staining.RESULTS:Compared with control group,the rats in NaHS group showed no signifi-cant differences in all laboratory tests(P>0.05).The rats in I/R group exhibited significant lung injury,oxidative stress,increased lactate level,and up-regulated glycolysis and pyroptosis(P<0.05 or P<0.01).Compared with I/R group,the indicators in L+I/R group showed a downward trend(P<0.01)or no difference(P>0.05),while those in M+I/R group dis-played a significant reduction(P<0.05 or P<0.01).However,the indexes in H+I/R group exhibited no significant dif-ferences in these tests(all P>0.05).CONCLUSION:A moderate dose(56 μmol·L-1·kg-1)of NaHS mitigated the oc-currence of pyroptosis by inhibiting the HK2-NLRP3-GSDMD pathway,thus contributing to the attenuation of lung I/R in-jury in rats.

Objective:To evaluate the effect of metformin preconditioning on adenosine monophosphate-activated protein kinase(AMPK)/PTEN-induced putative protein kinase(PINK1) signaling pathway during ischemia-reperfusion (I/R) injury in diabetic rats.Methods:Thirty-six clean-grade healthy male Sprague-Dawley rats, aged 6 weeks, weighing 120-160 g, were divided into 3 groups ( n=12 each) by the random number table method: diabetic sham operation group (DS group), diabetic myocardial I/R group (DI/R group) and diabetic myocardial I/R+ metformin preconditioning group(DI/R+ Met group). After 4 weeks of feeding a high-fat and high-glucose diet, the model of type 2 diabetes mellitus was induced by a single intraperitoneal injection of 1% streptozotocin 40 mg/kg. The myocardial I/R injury was induced by blocking the anterior descending branch of the left coronary artery for 30 min followed by 120-min reperfusion in anesthetized animals. In DI/R+ Met group, metformin 200 mg/kg was given by intragastric gavage once a day within 1 week before myocardial ischemia. Blood samples from the femoral vein were collected at 120 min of reperfusion for determination of the serum creatine kinase isoenzymes (CK-MB) and cardiac troponin I (cTnI) concentrations by enzyme-linked immunosorbent assay. Then the rats were sacrificed and myocardial tissues were obtained for examination of the pathological changes(by HE staining) and for determination of the percentage of myocardial infarct size (by the double staining of Ewan blue and TTC) and expression of myocardial autophagy-related protein Beclin-1, PTEN-induced putative kinase 1 (PINK1), phosphorylated 5′-adenosine monophosphate-activating protein kinase (p-AMPK), and ratio of microtubule-associated protein 1 light chain 3Ⅱ/Ⅰ (LC3Ⅱ/Ⅰ) (by Western blot). Results:Compared with DS group, the percentage of myocardial infarct size and serum CK-MB and cTnI concentrations were significantly increased, the expression of Beclin-1, p-AMPK and PINK1 in myocardial tissues was up-regulated, the ratio of LC3II/I was increased( P<0.05), and the pathological changes were aggravated in DI/R group and DI/R+ Met group. Compared with DI/R group, the percentage of myocardial infarct size and serum CK-MB and cTnI concentrations were significantly decreased, the expression of Beclin-1, p-AMPK and PINK1 in myocardial tissues was up-regulated, the ratio of LC3Ⅱ/Ⅰ was increased ( P<0.05), and the pathological changes were significantly reduced in DI/R+ Met group. Conclusions:The mechanism by which metformin preconditioning reduces myocardial I/R injury is related to activation of AMPK/PINK1 signaling pathway and up-regulation of mitochondrial autophagy in diabetic rats.

Chromium is a harmful contaminant showing mutagenicity and carcinogenicity.Therefore,detection of chromium requires the development of low-cost and high-sensitivity sensors.Herein,blue-fluorescent carbon quantum dots were synthesized by one-step hydrothermal method from alkali-soluble Poria cocos polysaccharide,which is green source,cheap and easy to obtain,and has no pharmacological ac-tivity due to low water solubility.These carbon quantum dots exhibit good fluorescence stability,water solubility,anti-interference and low cytotoxicity,and can be specifically combined with the detection of Cr(Ⅵ)to form a non-fluorescent complex that causes fluorescence quenching,so they can be used as a label-free nanosensor.High-sensitivity detection of Cr(Ⅵ)was achieved through internal filtering and static quenching effects.The fluorescence quenching degree of carbon dots fluorescent probe showed a good linear relationship with Cr(Ⅵ)concentration in the range of 1-100 μM.The linear equation was F0/F=0.9942+0.01472[Cr(Ⅵ)](R2=0.9922),and the detection limit can be as low as 0.25 μM(S/N=3),which has been successfully applied to Cr(Ⅵ)detection in actual water samples herein.

To investigate the stereoselective pharmacokinetics of itraconazole enantiomers in rats, four cis-ITR stereoisomers at the dose of 15 mg/kg were administered orally to rats. Blood was collected and single stereoisomer of ITZ and hydroxy-itraconazole(OH-ITZ)were determinated simultaneously by LC-MS/MS. Samples were extracted by protein precipitation with acetonitrile. Durashell HILIC column(100 mm×2. 1 mm, 5. 0 m)was used as the analytical column, while a mixture of solvent A(0. 02% acetic acid and 5 mmol/L ammonium acetate in water)and B(50% acetonitrile and 50% methyl alcohol)was used as the mobile phase. A 5. 5 min binary gradient elution(delivered at 0. 5 mL/min)was performed for the separation. LC-MS/MS was performed in positive ion mode with multiple reactions monitoring(MRM). The pharmacokinetic parameters of itraconazole enantiomers after the administration were estimated as follows: the plasma levels and AUC0-∞ of OH-(2S, 4R, 2R)-ITZ and OH-(2S, 4R, 2S)-ITZ were higher than those of OH-(2R, 4S, 2R)-ITZ and OH-(2R, 4S, 2S)-ITZ(P< 0. 001). At the same time, female rats exhibited greater cmax, t1/2, AUC0-∞ than male rats, and the absorption of male rats was more rapid than those of females. The findings indicate significant stereoselective differences in the pharmacokinetic parameters of itraconazole enantiomers and gender difference in rats.

BACKGROUND:With the development of modern orthodontics, to invent an efficient appliance is the focus in
recent studies. Transmission straight wire appliance was born on this background. This appliance can accelerate occlusion and shorten treatment duration. The relationship between distal width and angulation of gable bends of main arch wire needs to study in depth.
OBJECTIVE:To establish three-dimensional finite element model of transmission straight wire appliance with better biological and mechanical similarity, and to obtain the relationship between distal width and angulation of gable bend of main arch wire.
METHODS:By using scanning of spiral CT with 64 rows, the sectional image data in DICOM format of maxil ary dentition and maxil ae of the volunteers (Class Ⅱ, division 1) were obtained. With the help of Ansys workbench 13.0, Mimics 10.01, Unigraphics NX and Geomagic Studio 8.0 softwares, the three-dimensional finite element model including transmission straight wire appliance, bend, Australian Orthodontic Wire, maxil ae, maxil ary tooth and periodontal ligament was established in Windows XP Service Pack 3 system.
RESULTS AND CONCLUSION:A three-dimensional finite element model of transmission straight wire appliance was established, which consisted of 250 929 elements and 657 766 nodes. Furthermore, three-dimensional finite element model had higher geometric similarity and mechanical similarity, as wel as the advantages of adding or subtracting components according to the requirement of the research. The model was conductive to analyze the mechanical system of transmission straight wire appliance and guide the clinical application and appliance modification.

Objective To investigate the reliability of Narcotrend for monitoring the depth of sedation [the observer's assessment of alterness/sedation(OAA/S) scale] with midazolam and correlation between the depth of sedation and Narcotrend index.Methods 0 ASA Ⅰ-Ⅱ status patients scheduled for elective lower limb operations underwent spinal anesthesia,who were given target-controlled infusion of midazolam.Target plasma concentration was 50ng/ ml at first and increased by 10 ng/ml each grade until OAA/S scale became 1 point.Each target concentration infusion was maintained for 5min.Observe the patient the OAA/S scale to be 5 points.If the operation was not over yet,regulated the appropriate depth of sedation until the end of operation.The Narcotrend index of different OAA/S scale and heart rate,mean arterial pressure,respiration were recorded.Results In the deepening or recovery phase of sedation,OAA/S scales were correlated with Narcotrend index (Spearman' s r =0.786,0.652,all P ＜ 0.05).Conclusion Narcotrend is a good index to guide target controlled infusion of midazolam,the index is closely related with the depth of sedation of midazolam.

OBJECTIVETo study the expression of HIF-1alpha and SDF-1/CXCR4 in repopulating H22 tumor tissue and the mechanism of angiogenesis of polypeptide extract from scorpion venom (PESV) during chemotherapy treatment.

METHODThe expression of HIF-1alpha and SDF-1/CXCR4 in H22 tumor tissue was monitored by immunohistochemistry, and the expression level was determined by Qwin V3 image analyzing software. The correlation between HIF-1alpha and SDF-1 was analyzed. SDF-1 content was detected by ELISA.

RESULTHIF-1alpha expression was found no difference in model group between 14 d and 21 d, and up-regulated in 28 d. There was no change of HIF-1alpha expression was observed in low-dose PESV group. In high-dose PESV group, the level of HIF-1alpha expression was high in 14 d and low in 21 d. ELISA detecting showed SDF-1 content increased slowly from 14 d to 21 d, highly from 21 d to 28 d. But in high-dose PESV groups, the content increased slowly all the time. The immunohitochemistry method got the same result with ELISA. Correlation analysis showed r = 0.805. CXCR4 expression down-regulated in two PESV treated groups, and no difference was found between these two groups.

CONCLUSIONHIF-1alpha and SDF-1 participated in VEGF expression and angiogenesis in tumor tissue during chemotherapy, while PESV could inhibit the expression of HIF-1alpha and SDF-I.

Animals ; Cell Line, Tumor ; Chemokine CXCL12 ; drug effects ; metabolism ; Down-Regulation ; drug effects ; Hypoxia-Inducible Factor 1, alpha Subunit ; drug effects ; metabolism ; Mice ; Peptides ; pharmacology ; Receptors, CXCR4 ; drug effects ; metabolism ; Scorpion Venoms ; chemistry ; pharmacology ; Scorpions ; chemistry ; Time Factors