Multidrug resistance(MDR) is the leading cause of treatment failure in cancer therapy. Overexpression of the ATP-binding cassette (ABC) transporter family increases the cellular efflux, decreases the effectiveness of chemotherapeutic agents,and results in MDR. In particular,overexpression of P-glycoprotein and its encoding genes(mdr1) is the major mechanism. It is feasible for overcoming MDR by studying the factors affecting mdr1 gene expression so as to block the expression of mdr1. Pregnane X receptor(PXR) can regulate the expression of MDR proteins, suggesting that it be possible to overcome drug resistance by regulating PXR. In this paper,the relation between PXR and MDR and recent development of PXR antagonists to pharmacologically modulate PXR are reviewed. The review proposes that selectively preventing the elevation of MDR levels by regulating PXR rather than non-selectively inhibiting the MDR activity by using MDR inhibitors can be a less toxic approach to overcome drug resistance during cancer therapy.

OBJECTIVE: To explore the clinical application value of using needle electrode in transurethral plasmakinetic resection of bladder tumor around ureteral orifice. METHODS: Retrospective analysis was performed on the clinical data of 16 cases who had bladder tumors around ureteral orifice and underwent transurethral resection using plasmakinetic needle electrode in Department of Urology, Peking University International Hospital from June 2015 to December 2019. There were nine cases with the tumor of one to two centimeters from the ureteral orifice. The rest of the seven cases had tumor that was within one centimeter from the ureteral orifice, including two cases whose ureteral orifice was invaded by the tumor. All the patients studied were diagnosed before surgery and contraindications were excluded. The plasmakinetic needle electrode was used to treat the tumor with en bloc resection, and all the excised tissue was sent for pathological examination. Intravesical chemotherapy and postoperative follow-ups were performed. Statistical analysis was performed on the operation time, the incidence of obturator nerve reflex, the peri-operative bleeding, the parameters of indwelling ureteral catheter or double-J stent, the incidence of postoperative hydronephrosis, the clinical stage of tumor, and the recurrence rate. RESULTS: The operation was successfully completed for all the sixteen cases. The operation time was 16 to 57 minutes, with an average of (32.6±11.8) minutes. No obvious obturator nerve reflex and perioperative bleeding occurred in all the patients. Ureteral catheters were indwelled prior to the operation of tumor resection in seven cases. Four of the seven cases had the ureteral catheters remained while the rest three were replaced by double-J stent after surgery. Postoperative pathological analysis showed that all the tumors were urothelial carcinoma, including 9 cases of low grade and 7 cases of high grade. Pathological staging: 10 cases were in Ta stage, 5 cases in T1 stage, and 1 case in T2a stage. All tumor bases and lateral margins were negative. All the patients received 3-56 months, with an average of (26.0±18.1) months of follow-up. There was no case of upper urinary tract hydronephrosis or tumor recurrence. CONCLUSION The transurethral plasmakinetic resection of bladder tumor using needle electrode can realize en bloc tumor resection without obturator nerve reflex and reduce the risk of ureteral orifice injury. It is a safe and effective surgical method for treating bladder tumors around the ureteral orifice.
Carcinoma, Transitional Cell ; Electrodes ; Humans ; Neoplasm Recurrence, Local ; Retrospective Studies ; Urinary Bladder Neoplasms/surgery*

Mind map is an effective and intuitive knowledge organization and presentation tool which can help computer teaching commendably. We can use Mind Map to design and organize the whole teaching process, including preparing, designing, guiding, analyzing and reviewing. This way can turns tedious logic of computer teaching into imagery thinking and helps medical students improv-ing their learning effect of computer courses.

Humans ; Neck ; Solitary Fibrous Tumors

OBJECTIVE: To investigate berberine's potential to enhance the sensitivity of doxorubicin-resistant human leukemia cell lines (K562/DOX) to doxorubicin in vitro. METHODS: MTT assay was performed to determine the effect of berberine on the sensitivity of K562/DOX cells to doxorubicin. Doxorubicin accumulation assay was performed by Arrary Scan VTI HCS600 High-Contents. The effect of berberine on doxorubicin-induced cell apoptosis was tested by PI/Hoechst 33342 assay. The efflux activity of P-gp was investigated by measuring the accumulation of the rhodamine 123 after treatment with berberine. RESULTS: μmol · L-1 of berberine, as a wild dose, reduced IC50 of doxorubicin to K562/DOX cells by 1.5 times. 1 μmol · L-1 of berberine showed the enhancement effect on doxorubicin-induced apoptosis. The increase of doxorubicin and rhodamine 123 accumulation was observed in K562/ DOX cells treated with 1 μmol · L-1 of berberine which indicated the inhibition of the activity of P-gp. CONCLUSION: Berberine is shown to effectively enhance chemosensitivity of K562/DOX cells to Dox by inhibiting the efflux activity of P-gp.

Two parental strains BY-14 and BY-6,with high leavening ability in lean and sweet dough respectively,were selected.Through spore production and separation,two haploids with opposition types were selected for cross-breeding.At last one hybridization strain was obtained,with good fermentation ability as BY-14 in lean dough and better than BY-6 by 25%in sweet dough.

Objective To study the distribution of intestinal autofluorescent microorganisms in the rat intestine at different developmental stages. Methods The distribution of intestinal autofluorescent microorganisms in rat intestine at va-rious developmental stages was tested and evaluated using a small animals living imaging system. First, standard E. coli strain was tested by fluorescence detection in vitro. Then, the distribution of E. coli under the same test conditions was tested. The intestinal autofluorescent bacteria distribution was detected in the SD rats at 3 days,14 days and 60 days of age. After expanding the range of excitation wavelength fluorescence detection,removing the background of fluorescence feed and feces and other foreign autofluorescent substances. Results E. coli can be excited in the range of 485 -535 nm wave?length and to emit fluorescence. E. coli mainly existed in the stomach and only a few E. coli were found in the ileum of 3?days old SD rat. . In the 14?days old rats, E. coli mainly existed in the stomach and cecum, and only a few E. coli were found in the ileum. In the 60-days old SD rats, E. coli mainly existed in the ileum, and only a few E. coli were found in the colon, cecum and jejunum. After the expansion of the excitation light wavelength range of fluorescence detection, E. co?li were observed mainly in the ileum, and only a few E. coli were found in the stomach in 3?days old SD rat. E. coli mainly existed in the stomach, then the cecum and only a few E. coli were found in the ileum and jejunum in 14-days old SD rats. E. coli could be found in the whole intestinal system but mainly in the ileum and cecumin of the 60-days old rats. Conclu?sions Examining the intestinal autofluorescent microbes with the small animal in vivo imaging system can be helpful and make guidance to study the distribution of intestinal microbes in the host at different developmental stages, and to provide a basis for studying the relationship of intestinal microbes with its host and the gastrointestinal drug administration.

Objective To investigate the effect of electroacupuncture at point Fenglong(ST40) on the expressions of macrophage surface antigen CD11b and intercellular adhesion molecule-1 (ICAM-1) in hyperlipidemia rats. Method Forty healthy SD rats were randomly allocated to normal control, high fat diet, high fat+common diet, high fat diet and treatment, and high fat+common diet and treatment groups. After 28 days of treatment with electroacupuncture at point Fenglong, blood lipid levels, namely, total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) contents were measured in every group of rats. The expressions of peritoneal macrophage surface antigen CD11b and ICAM-1 were examined using flow cytometry (FCM) in every group of rats. Result Plasma TC and LDL-C increased significantly in the high fat diet group of rats compared with the normal control group (P<0.01). In the high fat+common diet group of rats, serum TC and LDL-C decreased significantly in comparison with the high fat diet group (P<0.01) but increased significantly in comparison with the normal control group (P<0.01). After treatment with electroacupuncture at point Fenglong, rat plasma TC and LDL-C decreased significantly (P<0.01) and TG and HDL-C did not change significantly (P>0.05). The expression rates of macrophage CD11b and ICAM-1 increased significantly in the high fat diet group of rats compared with the normal group (P<0.01). In the high fat+common diet group of rats, the expression rates of macrophage CD11b and ICAM-1 decreased significantly in comparison with the high fat diet group (P<0.05) but increased significantly in comparison with the normal group (P<0.01). The expression rates of CD11b and ICAM-1 decreased significantly in the high fat diet and treatment group compared with the high fat diet group (P<0.01) and decreased significantly in the high fat+common diet and treatment group compared with the high fat+common diet group (P<0.01) and the high fat diet and treatment group (P<0.01). Correlation analysis showed that CD11b and ICAM-1 levels had a significantly positive correlation (r=0.947, P<0.01). Conclusion Electroacupuncture at point Fenglong can significantly down-regulate blood fat TC and LDL-C levels and the expressions of macrophage CD11b and ICAM-1 in hyperlipidemia rats. It has a certain therapeutic effect on hyperlipidemia.

Objective To investigate the effects of sodium aescinate(SA)on oxidative stress and pulmonary function during acute exacerbation of chronic obstructive pulmonary disease(COPD).Methods One hundred and twenty patients with COPD were randomly divided into two groups:the control group(n =60) and the treatment group(n =60).All patients were treated with routine anti-infection,oxygen inhalation,relieving phlegm and anti-asthma The treatment group took SA in addition to the routine beteropathy.The changes of serum SOD,MDA,GSH-Px,T-AOC,pulmonary functions and 6 minute walk distance(6MWD) were detected before and after two-week treatment in patients of the two groups to compare with 60 healthy subjects.Results The total effective rate in the treatment group was 91.67％,while 76.67％ in the control group.The difference was statistically significant(x2 =5.065,P ＜0.05).Serum MDA level in both groups were comparatively higher than the healthy controls(9.25±1.55) μmol/L vs.(9.74±1.50) μmol/L vs.(2.06±0.29) μmol/L,P ＜0.001),while the levels of SOD,GSH-Px and T-AOC were lower than the healthy controls[SOD:(91.14±9.54) kU/L vs.(90.61±8.01) kU/L vs.(116.63±6.57) kU/L; GSH-Px:(139.38±36.56) U vs.(137.57±34.19) U/L vs.(189.34±35.54) U/L; T-AOC:(6.48±1.15) kU/L vs.(6.39±1.13) kU/L vs.(13.34±1.23)kU/L;P < 0.001].After treatment,all indexes of the two groups were obviously ameliorated in comparison with before treatment(P ＜ 0.001),but the level of MDA[(4.56±1.39) μmol/L]in the treatment group decreased more greatly than in the control groups(P ＜ 0.001).The levels of SOD[(103.85±7.07) kU/L],GSH-Px[(169.65±34.51) U/L],T-AOC[(10.52±1.09) KU/L],forced expiratory volume in 1 second/forced vital capacity(FEV1/FVC)[(60.49±6.11)％],FEVI％[(76.62±6.35)％]and 6MWD [(394.83±10.11)m]increased considerably more than those in the control group(P ＜ 0.001).Conclusion Oxidative stress might be involved in the course of acute exacerbation of COPD.Sodium aeseinate can improve the pulmonary functions by ameliorating the oxidative stress during acute exacerbation in patients with COPD.

AIM:To investigate the inhibitory effects of recombinant human Mullerian inhibiting substance on cell proliferation in human ovarian carcinoma cells (OVCAR8 and SKOV3 cell lines). METHODS:The expression of MISIIR protein and the localization of MISIIR protein were analyzed by Western blotting and confocal spectral microscopy,respectively. Cell apoptosis and cell cycle were detected by flow cytometry (FCM). Cell viability was determined via MTT method. Clone formation test was used to detect oncogenicity in vitro.RESULTS:The MISIIR protein expression in OVCAR8 cells but not in SKOV3 cells was observed. MISIIR expression was seen on the OVCAR8 cell surface and in the cytoplasm with both antibodies. After treated with rhMIS for 48 h,the cell viability was significantly decreased in OVCAR8 cells. rhMIS inhibited the oncogenicity of OVCAR8 cells greatly. The cell apoptosis of OVCAR8 cell exposed to 10 mg/L rhMIS was (31.3±2.1)%,and OVCAR8 cells in the G_1 phase were increased by (70.4±3.0)%. Compared to SKOV3 cells the differences were significant (P<0.01). CONCLUSION:Recombinant human Mullerian inhibiting substance suppresses the growth of MISIIR-positive ovarian cancer cells by inducing apoptosis and cell cycle arrest. We predict that rhMIS might be a new target to treat human ovarian malignancies.