Background and purpose: Multidrug resistance (MDR) is the dominating obstacle to the chemotherapy. There is strong evidence that the phosphoinositide 3-kinases (PI3Ks) signaling pathway is involved in MDR phenotype, however, the mechanism of MDR occurrence is still unknown. This study tended to investigate the regulating effect of PI3K/Akt signaling pathway and its downstream target genes in P-glycoprotein (P-gp) (ABCB1 gene encoding)-mediated MDR in human colon carcinoma HCT-116/L-OHP cells. Methods:Pretreatment with PI3K selective inhibitor LY294002 (20μmol/L) for 2 h, the sensitivity of L-OHP was evaluated by the CCK-8 (cell counting kit-8) assay in HCT-116/L-OHP cells, and the expressions of P-gp, LRP, MRP-2, Akt, p-Akt, IκB and p-IκB were evaluated by Western blot. The activity of ABCB1 promoter was evaluated by chromatin immunoprecipitation analysis (CHIP). Results: After inhibiting the activity of PI3K/Akt signaling pathway, the IC50 value of L-OHP decreased from(157.48±16.73)μg/mL to (53.68±3.18)μg/mL in HCT-116/L-OHP cells, and the reversal index was 2.93 (P<0.01). The expressions of P-gp, p-Akt and p-IκB were down-regulation compared with the concrol group (P<0.01), but the expressions of LRP, MRP-2, Akt and IκB didn't change signiifcantly. CHIP result has conifrmed that NF-κB protein could bind to the region of ABCB1 gene promoter in HCT116/L-OHP cells. Conclusion:Blocking of PI3K/Akt/NF-kB signal pathway could increase the drug sensitivity to MDR cells, inhibit the phosphorylation of p-Akt and p-IκB, and reversing ABCB1/P-glycoprotein-mediated multidrug resistance in colon carcinoma cells.

Objective To investigatethe role of NF-κB played in the process of the cord blood monocytes differentiating into dendritic cells(DCs)induced by astragalus polysaccharide(APS)and to explore the signal transduction pathway involved in this process.Methods Umbilica]cord blood was collected in aseptic conditions.The cord blood monocytes were obtained by density gradient centrifugation and were divided into three groups afterwards.In the control group.cells were cultivated in the RPMI 1640 complete medium.In the APS group.cells were cultivated in the RPMI 1640 complete medium containing 100 mg/L APS.In the PDTC group:cells were treated with 10 μmol/L disulfide carbamate(PDTC).NF-κB inhibitor in 30 min followed by cultivalion in the RPMI 1640 complete medium containing 100 mg/L APS.,The morphological changes were observed during the process of cultivation by the optical microscope and transmission electron microscopy.Cells were collected 12 d later and the cellular immunophenotyping was assayed by FCM.,The activation and migration of NF-κB fluorescence in the cells was examined by the immunoflouresce microscopy.Results (1)Cells in the control group grown up without cluster forformation and were found fusiform and macrophage-like in 12 d.Cells in the APS group grown up in clnstem,and morphological changes were found from the circular shape to a typical dendritic cells-like shape.Cells in the inhibitor group grown up slowly and without cluster formation,and cell morphdogy had no significant change.(2)The expression of DCs-specific antigen CD80,CD83 and CD86 in the APS group was higher than that in the control group and inhibitom group(P<0.01).The expression of those antigen in the control group and PDTC group was similar and had no statistically significance(P>0.05).(3)NF-κB fluorescence in the nuclei was examined by the immunoflourescence microscopy and was much higher in the APS group than that in khe other groups,especially in 72 h with the activation rate of NF-κB (75.20±7.37)%,while(13.20±3.46)% of PDTC group and(8.20 ±1.92)%,respectively(P<0.01).Conclusion Astragalus polysaccharide can induce the differentiation of umbilical cord blood cells into DCs,and NF-κB is the key component of the signal transduction pathway involved in this process.

Objective To investigate the diagnostic value of CTP-SI in acute stroke less than 9 hours.Methods In present study."one-stop shop"CT examination were performed in 34 patients with symptoms of acute stroke in le88 than 9 hours.We divided patients into two groups according to with and without delayed perfusion on CTP-SI.and compared ASPECTS (Alberta Stroke Program Early CT Score Study)scores on non-contrast CT(NCCT),arterial phase CTP-SI,venous phase CTP-SI with follow-up imaging.The ASPECTS were analyzed on arterial phase CTP-SI and veIlous phase CTP-SI using Wilcoxon rank-sum test.then compared with the follow up imaging ASPECTS using multiple linear regression.Results The median(min-max)scores of ASPECTS on NCCT,arterial phase CTP-SI,venous phase CTP-SI and follow-up imaging were 9.0(6.0-10.0),6.5(1.0-8.0),8.0(3.0-10.0)and 7.0(0-10.0)in group with delayed perfusion,respectively,and 9.0(1.0-10.0),8.5(1.0-10.0),8.5(1.0-10.0)and 8.0 (0～10.0)in group without delayed perfusion respectively.ASPECTs scores measured on arterial phase CTP-SI did not differ from venous phase CTP-SI in group without delayed perfusion ( Z = - 1.00, P =0.317), while there was significant difference in group with delayed perfusion (Z = -3.08, P = 0.002 ).There were significant correlation with ASPECTS scores measured on NCCT, arterial phase CTP-SI and venous phase CTP-SI to follow-up imaging ASPECTS (r =0.899,0.926,0.928,P ＜0.01 ) in group without delayed perfusion; ASPECTS measured in venous phase CTP-SI showed the best correlation to follow-up imaging ASPECTS (r = 0.762, P = 0.004) in group with delayed perfusion.Multiple linear regression showed that the correlation in only venous phase CTP-SI with foUow-up imaging ASPECTS was statistically significant:in group without delayed perfusion, Beta = 0.966, P ＜ 0.001 ; in group with delayed perfusion,Beta = 0.765, P = 0.004. Conclusion Presence of delayed porfusion in CTP-SI is quite important in identifying ischemic penumbra, which plays a critical role in imaging-guided thrombolytie therapy.

OBJECTIVETo observe the effect of OHOLV on the remineralization of early enamel caries.

METHODSFifty bovine teeth with artificial early caries were divided into five groups randomly and treated with OHOLV, casein phosphopeptide amorphous calcium phosphate (CPP-ACP), NaF, OHOLV+NaF and distilled and deionized water (DDW) respectively. Then the teeth were subjected to the pH-cycling. The surface microhardness (SMH) of enamel before demineralization and after remineralization were measured by microhardness detector and the histomorphologic changes of the enamel surface were compared by scanning election microscope (SEM).

RESULTSThe SMH of all the experimental groups increased significantly after remineralization (P < 0.001). The SMH of the OHOLV group was lower than that of NaF group (P < 0.001), while there was no significant difference between the OHOLV group and the CPP-ACP group (P > 0.05). After remineralization, a large amount of comparatively large mineral particles deposited on the surface of the enamel treated with OHOLV.

CONCLUSIONOHOLV can promote the remineralization of the early enamel caries.

Animals ; Calcium Phosphates ; Cariostatic Agents ; Caseins ; Cattle ; Dental Caries ; Dental Enamel ; Tooth Remineralization

To optimize program of bovine somatic nuclear transfer, we used two different enucleation procedures (by Spindle-view system & Hoechst 33342 staining), two different procedures to introduce donor nuclei (by ooplasm microinjection & electrofusion), and three different group electrofusion parameters (group 1: 1.9 kV/cm, 10 micros, two; group 2: 1.5 kV/cm, 25 micros, two; group 3: 0.6 kV/cm, 100 micros, one) to reconstruct bovine cloned embryos. The cleavation rates and blastocyst development rates of cloned embryos were used to assess the efficiency of different operational procedure. Finally, the best combination of operational procedure, that the spindle-viewer system was used for oocytes enucleating, and donor cell was electrofused into ooplasm by electrical pulse (1.9 kV/cm, 10 micros, two) to reconstruct bovine cloned embryos. Then the excellent blastocysts were transferred to fosters for producing cloned cattle 80 high-quality cloned blastocysts were transferred into 33 fosters, two cloned calves were produced. According to the results, the optimized program could be used to produce cloned cattle.
Animals ; Cattle ; Cell Nucleus ; physiology ; Cloning, Organism ; veterinary ; Embryo Transfer ; methods ; Embryo, Mammalian ; cytology ; physiology ; Female ; Microinjections ; Nuclear Transfer Techniques ; veterinary ; Oocytes ; cytology ; physiology

The stenosis and embolization of internal fistula vessels directly affect the clinical treatment effect of maintenance hemodialysis patients, and the study of the mechanism of internal fistula stenosis has become a research hotspot in recent years. Previous studies mainly focused on the hemodynamics and pathophysiology of blood vessel wall, and there were few studies on molecular biology and its related signaling pathways. This paper reviews the hemodynamics of the vascular pathway of internal arteriovenous fistula (AVF), the pathophysiological mechanism, molecular biology, and changes in various signaling pathways of AVF dysfunction at home and abroad, in order to provide references for the study of AVF dysfunction.

Objective To observe the differences in the expression levels of the hypoxia-induc-ible factor-1α/heme oxygenase-1/vascular endothelial growth factor A(HIF-1α/HO-1/VEGF-A)signaling pathway under different maturation outcomes of arteriovenous fistula(AVF)in patients with stage 5 chronic kidney disease,and explore the regulatory mechanism of the HIF-1α/HO-1/VEGF-A signaling pathway in the maturation process of AVF.Methods A total of 45 patients with AVF sur-gery for stage 5 chronic kidney disease were selected as research objects,vascular specimens were col-lected during the AVF surgery,and the patients were divided into AVF maturation group(n=35)and AVF poor maturation group(n=10)based on the AVF maturation outcomes within 8 weeks after surgery.Reverse transcription-polymerase chain reaction(RT-PCR)was used to detect the gene ex-pression levels of HIF-1α,HO-1 and VEGF-A in the HIF-1α/HO-1/VEGF-A signaling pathway;the Western blotting was used to detect the protein expression levels of HIF-1α,HO-1 and VEGF-A;the enzyme-linked immunosorbent assay(ELISA)was used to detect the expression levels of downstream inflammatory factors such as interleukin-1β(IL-1β),interleukin-8(IL-8),and transforming growth factor-β(TGF-β).Results The expression levels of HIF-1α mRNA,HO-1 mRNA,and VEGF-A mRNA in the AVF maturation group were significantly higher than those in the AVF poor maturation group(P＜0.01);the protein expression levels of HIF-1α,HO-1 and VEGF-A in the AVF maturation group were significantly higher than those in the AVF poor maturation group(P＜0.01);the ex-pression levels of IL-1β,IL-8 and TGF-β in the AVF maturation group were significantly lower than those in the AVF poor maturation group(P＜0.01).Conclusion The upregulation of the HIF-1α/HO-1/VEGF-A signaling pathway is conducive to the early maturation of AVF.The measurement of the expression levels of the HIF-1α/HO-1/VEGF-A signaling pathway has a certain predictive sig-nificance for the early maturation outcome of AVF.

Objective To observe the differences in the expression levels of the hypoxia-induc-ible factor-1α/heme oxygenase-1/vascular endothelial growth factor A(HIF-1α/HO-1/VEGF-A)signaling pathway under different maturation outcomes of arteriovenous fistula(AVF)in patients with stage 5 chronic kidney disease,and explore the regulatory mechanism of the HIF-1α/HO-1/VEGF-A signaling pathway in the maturation process of AVF.Methods A total of 45 patients with AVF sur-gery for stage 5 chronic kidney disease were selected as research objects,vascular specimens were col-lected during the AVF surgery,and the patients were divided into AVF maturation group(n=35)and AVF poor maturation group(n=10)based on the AVF maturation outcomes within 8 weeks after surgery.Reverse transcription-polymerase chain reaction(RT-PCR)was used to detect the gene ex-pression levels of HIF-1α,HO-1 and VEGF-A in the HIF-1α/HO-1/VEGF-A signaling pathway;the Western blotting was used to detect the protein expression levels of HIF-1α,HO-1 and VEGF-A;the enzyme-linked immunosorbent assay(ELISA)was used to detect the expression levels of downstream inflammatory factors such as interleukin-1β(IL-1β),interleukin-8(IL-8),and transforming growth factor-β(TGF-β).Results The expression levels of HIF-1α mRNA,HO-1 mRNA,and VEGF-A mRNA in the AVF maturation group were significantly higher than those in the AVF poor maturation group(P＜0.01);the protein expression levels of HIF-1α,HO-1 and VEGF-A in the AVF maturation group were significantly higher than those in the AVF poor maturation group(P＜0.01);the ex-pression levels of IL-1β,IL-8 and TGF-β in the AVF maturation group were significantly lower than those in the AVF poor maturation group(P＜0.01).Conclusion The upregulation of the HIF-1α/HO-1/VEGF-A signaling pathway is conducive to the early maturation of AVF.The measurement of the expression levels of the HIF-1α/HO-1/VEGF-A signaling pathway has a certain predictive sig-nificance for the early maturation outcome of AVF.