Objective To explore the effect of ?-elemece on the reverse of drug resistance and the expression of P-glycoprotein(P-gp) in MDR K562/ADM cells. Methods MTT method was used to detect the sensitivity of cell and its reverse of drug resistance.Immunohistochemistry and immunoelectron microscopy were for observing the expression of P-gp.It's quantitative analysis was determined by flow cytometry.All experimental data were dealt with by SPSS(10.0 production pacility) soft ware. Results 1.Non-cytotoxic dose of ?-elemece(4.0?mg/L) could obviously decrease the IC-(50) value of K562/ADM cells to ADM.The reversing fold was 2.18;2.The level of P-gp expression was higher in K562/ADM cells than that in its parent K562 cells.Our studies also showed that the distribution of P-gp was on membrane of K562/ADM cells;3.Non-cytotoxic dose of ?-elemece(4.0?mg/L) could remarkably decrease the P-gp expression in MDR K562/ADM cells.Conclusion\ ?-elemece could evidently reverse drug resistance of K562/ADM to ADM.Decreasing the P-gp expression in drug resistance cell is one of the main mechanism of reversion.

OBJECTIVETo observe the effect of atorvastatin on eNOS synthesis in the vital organs of aging rats and explore its mechanism for protection against myocardial ischemia-reperfusion injury.

METHODSTwenty-month-old Wistar rats were given daily atorvastatin lavage for 4 months. Myocardial ischemia-reperfusion model was established by ligating the coronary artery. The rats were randomized into normal control group, untreated model group, medication without surgery group, and atorvastatin-treated surgical group. The content of eNOS in the heart, liver and kidneys was detected by Western blotting, and eNOS mRNA expression by RT-PCR. The effects of different doses of atorvastatin on eNOS expressions were also evaluated.

RESULTSAtorvastatin significantly promoted eNOS synthesis in the heart, liver and kidney of the rats (P<0.05) regardless of myocardial ischemia-reperfusion. A higher dose of atorvastatin caused a more obvious increase of eNOS protein and mRNA expression in the vital organs of the aging rats (P<0.05).

CONCLUSIONAtorvastatin can increase eNOS synthesis in the vital organs of aging rats, which partially explains the organ-protective effect of atorvastatin against myocardial ischemia- reperfusion.

Animals ; Atorvastatin Calcium ; Female ; Heptanoic Acids ; administration & dosage ; pharmacology ; Kidney ; metabolism ; Liver ; metabolism ; Male ; Myocardial Reperfusion Injury ; drug therapy ; metabolism ; Myocardium ; metabolism ; Nitric Oxide Synthase Type III ; genetics ; metabolism ; Pyrroles ; administration & dosage ; pharmacology ; Rats ; Rats, Wistar

Objective To investigate the early warning value of miR-29b in evaluating coronary plaque rupture in patients with stable coronary artery disease(SCAD),and the possible mecha-nism of its causing coronary plaque rupture.Methods A total of 210 SCAD patients treated in our department from April 2020 to April 2022 were selected and divided into PCI group(95 cases)and coronary angiography(CAG)group(115 cases).The expression level of miR-29b in peripheral blood before and after treatment were compared between the two groups.Human peripheral blood mononuclear cells(PBMC)were divided into blank control group,miR-29b group(transfected with miR-29b plasmid)and miR-29b blank group(transfected with miR-29b blank plasmid).The mRNA and protein levels of extracellular matrix metalloproteinase-inducing factor(EMMPRIN),NF-κB,and IL-6 were compared in the 3 groups.Results The expression of miR-29b after PCI was higher than that before PCI,and the expression level after PCI was significantly higher than that after CAG(P＜0.01).ROC curve analysis showed that the cut-off value of preoperative miR-29b in diagnosing coronary plaque rupture was 0.86,and the AUC value was 0.838(95％CI:0.707-0.970).Multivariate logistic regression analysis indicated that preoperative miR-29b was an independent predictor of plaque rupture in the SCAD patients(OR=0.598,95％CI:0.394-0.908,P=0.016).Pearson correlation analysis displayed that preoperative miR-29b was negative-ly correlated with EMMPRIN mRNA level in PBMC(r=-0.575,P＜0.01).In the in vitro experiment,the expression of EMMPRIN,NF-κB and IL-6 at mRNA and protein levels were sig-nificantly lower in the miR-29b group than the blank control group and the miR-29b blank group(P＜0.05).Conclusion Elevated miR-29b level after PCI in SCAD patients is a protective factor for coronary plaque rupture.Its mechanism may be that miR-29b inhibits plaque rupture by down-regulating the expression of EMMPRIN in PBMC.

Objective To explore the clinical significance of monitoring drainage fluid parathyroid hormone (dPTH) for estimating the in situ reserves and function of the parathyroid by analyzing the change of serum calcium,serum parathyroid hormone(sPTH) and dPTH after thyroid surgery.Methods According to the operative method,the total of 144 patients with thyroid disease were divided into five groups:unilateral lobectomy,unilateral lobectomy plus isthmectomy with unilateral lymph node dissection,total thyroidectomy,total thyroidectomy with unilateral lymph node dissection,and total thyroidectomy with bilateral lymph node dissection group.The blood calcium,sPTH and dPTH level of patients were tested before operation and on the 1st,2nd,3rd and 4th day after operation.The depression of serum calcium,hypocalcemia and hypoparathyroidism were observed after operation.The serum calcium,serum PTH and dPTH level were summarized and analyzed statistically in order to evaluate the in situ reserves and postoperative function of the parathyroid.Results Among the 114 cases,the decline of serum calcium level mostly happened on the 2nd day after operation(70 cases,61.4％).There were 36 patients with hypocalcemia (31.58％) and 34 patients with hypoparathyroidism (29.82％).Serum calcium level increased gradually in all of the patients.Although sPTH level swung,it had a rising trend on the whole.The level of serum calcium and sPTH was positively correlated.The level of dPTH was discrete and decreased along with time.The decline level of dPTH among different groups had statistical difference.Conclusions It is a promising method to evaluate the in situ reserves and function of the parathyroid by monitoring the level and changes of dPTH after thyroid surgery,and it is of value for preventive calcium supplementation after thyroid surgery.

Objective: To explore the clinical significance of metastasis of lymph nodes between sternocleidomastoid and sternohyoid muscle (LNSS) in papillary thyroid cancer (PTC). Methods: A total of 175 patients with PTC who underwent thyroidectomy with LNSS dissection were retrospectively analyzed. Univariate and multivariate Logistic regression analyses were used to determine the independent risk factors for LNSS metastasis in PTC. Results: The rate of detectable LNSS was 70.9% (124/175) and metastasis rate was 7.4% (13/175). Of 13 cases with LNSS metastasis, 10 with the coexistence of cervical lymph node metastasis. Univariate Logistic regression analysis showed that multiple focal cancer, tumor located in the lower pole of thyroid, belt-shaped muscle invasion, lateral cervical lymph node metastasis, cN+ , the number of cervical lymph nodes with metastasis and the number of lymph nodes with metastasis in level Ⅳwere the risk factors for LNSS metastasis (P<0.05). Multivariate Logistic regression analysis suggested that tumor located in the lower pole of thyroid and the number of cervical lymph nodes with metastasis >6 were the independent risk factors for LNSS metastasis (P<0.05). Given the number of cervical lymph nodes with metastasis as a predictor for the LNSS metastasis, the sensitivity was 92.3%, the specificity was 66.7% and the accuracy rate was 68.6%. Conclusions LNSS metastasis is commom in PTC, with a metastasis rate of 7.4%. PTC in the lower pole of thyroid and the number of cervical lymph nodes with metastasis > 6 are independent risks for LNSS metastasis.