Background and purpose:Remarkable advances have been made in cancer chemotherapy by developing new anticancer drugs and therapy strategies.However,multidrug resistance in human cancers remains a major clinical challenge for cancer treatment.Attempts in several clinical studies to reverse multidrug resistance protein (MDR) by using MDR modulators have not yet generated promising results.Our aim was to explored the mechanism of reversal of multidrug resistance in human leukemia K562 cells by PI3-K inhibitor.Methods:Trypanblue dye exclusion method was used to observe the drug sensitivity and the effect of LY294002 on the drug resistance.Western blot to analyze P-gp and p-Akt phenotypes,and flow cytometer was used to measure the intracellular drug accumulation. Results:K562/D induced by DNR was cross resistant to DNR,ADR,VCR and VP16 (Resistance Index:65,52,134 and 50 respectively).DNR induced over-expressions of P-gp and p-Akt in K562/D cells;LY294002 increased the intracellular drug accumulation,and then reversed the drug resistance to DNR,ADR,VCR and VPI6 in K562/D cells(Resistance Index:23,21,63 and 29 respectively),but not in the sensitive cells (K562/S).Conclusion:The multidrug resistance of K562/D cells can be induced by DNR which is related to the P-gp and p-Akt over-expressions, and LY294002 can reverse multidrug resistance in human leukemia cells in vitro via inhibits PI3-K/Akt pathway.

OBJECTIVETo observe the effect of Baichanting Compound (BC) on dopamine (DA) in striatum of Parkinson's disease (PD) mice, and to screen the optimal component proportion.

METHODSThe PD model was established in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induced C57BL/6 mice. By using uniform design, they were intervened by three extracts of BC in different proportions [Acanthopanax senticosus extract (X1): white peony root extract (X2): Uncaria rhynchophylla extract (X3) = 30.00: 34.92: 82.50, 48.00: 19.98: 72.19, 18.00: 44.88: 61.88, 36.00: 29.94: 51.56, 54.00: 15.00: 41.25, 24.00: 39.90: 30.94, 42.00: 24.96: 20.63). Equal volume of 5% carboxymethylcellulose sodium was administered to mice in the model group and the normal group by gastrogavage. All medication was lasted for 20 successive days. The dopamine (DA) content was determined by ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS). Except 10 in the normal group, 20 PD model mice were screened and divided into the model group and the BC group (with the optimal proportion) according to random digit table. BC extract in optimal proportion was administered to mice in the BC group by gastrogavage, while equal volume of 5% carboxymethylcellulose sodium was administered to mice in the model group and the normal group by gastrogavage. All medication was lasted for 20 successive days. Praxiology was observed in each group. DA content in striatum was also detected. Results Compared with the normal group, the DA content in striatum decreased significantly in the model group (P < 0.01), suggesting a successful PD modeling. Compared with the model group, the DA content in striatum increased significantly in 1 and 2 groups (P<0.05). According to results of quadratic polynomial stepwise regression statistics, the regression equation obtained was: Y = 0.265 + 0.026 X 2 - 0.056 X 3 + 0.334 x 10(-3) x X1 x X3 + 0.691 x 10(-3) X X3(2). X3 extract was the main factor influencing the effectiveness (P < 0.01). The optimal proportion of BC was predicted by the regression equation: X1 = 54.00 mg/(kg x d), X2 = 44.88 mg/(kg x d), the X3 = 82.50 mg/(kg x d). The pole climbing time was shortened, times of autonomic activities increased, DA content was elevated, all with statistical difference in BC groups (P < 0.01, P < 0.05).

CONCLUSIONBC could increase DA content in PD model mice with the optimal proportion as 54.00: 44.88: 82.50.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine ; Animals ; Disease Models, Animal ; Dopamine ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Mass Spectrometry ; Mice ; Mice, Inbred C57BL ; Motor Activity ; Parkinson Disease ; drug therapy ; metabolism

OBJECTIVETo explore the role of sTRAIL in the pathogenesis of HBV infection in human being.

METHODSsTRAIL in 153 patients' sera was examined with ELISA. Correlations between sTRAIL and liver functional parameters were analysed.

RESULTSThe levels of sTRAIL in patients with various clinical types of hepatitis B as well as primary hepatocellular carcinoma were all higher than that in normal persons and became almost normal in recovering stage cases. In acute and chronic HBV infection, sTRAIL level was negatively correlated with ALT, AST and total bilirubin levels, and positively correlated with serum albumin.

CONCLUSIONThe results indicated that higher level of sTRAIL expression is correlated with liver damage, and apoptosis induced by sTRAIL is one of the mechanisms of liver damage in HBV infection.

Adolescent ; Adult ; Aged ; Alanine Transaminase ; blood ; Aspartate Aminotransferases ; blood ; Enzyme-Linked Immunosorbent Assay ; Female ; Hepatitis B ; blood ; Hepatitis B, Chronic ; blood ; Humans ; Liver Cirrhosis ; blood ; virology ; Liver Neoplasms ; blood ; virology ; Male ; Middle Aged ; Serum Albumin ; analysis ; TNF-Related Apoptosis-Inducing Ligand ; blood ; Young Adult

Full-length NS5A gene of the hepatitis C virus was amplified by PCR using plasmid pBAC25 containing HCV nonstructural gene as template. The amplified fragment (about 1.34 kb) was cloned into plasmid pQE32, and the recombinant plasmid pQENS5A was expressed in JM109 strain. The NS5A protein was purified by NiSO4 metal chelating resin, and characterized by Western-blot. Its antigenecity was determined by ELISA. The positive detection rate of anti-NS5A was 75% (69/92) in ninety-two clinic sera. The positive rate of anti-NS5A was 82.5% (33/40) in fourty positive standand sera, and the negative rate of anti-NS5A was 100% (40/40) in fourty negative standand sera. The results showed that the Full-length NS5A proteinn had the higher sensitivity and specificity in the detection of HCV antibody in sera, we suggested that NS5A protein was a useful antigen for blood screening.

The drug-loading system of DMF (dextran - magnetic layered double hydroxide - fluorouracil) was synthesized by "co-precipitation intercalated assembly - dextran composite in situ - solvent conversion" technology. The crystal-phase characteristic and slow-release performance of DMF were investigated through X-ray diffraction (XRD), infrared spectrum (IR), transmission electron microscopy (TEM), thermogravimetry (TG) and in vitro release experiment. The targeted transshipment and slow-release effect of DMF system were evaluated by in vivo animal experiment. It was showed that the XRD of DMF matched with R-sixtetragonum type layered double hydroxide and Fd-3m cubic type ferrite. IR test demonstrated that the DMF system was a supra-molecular complex consisted of Dextran (DET), magnetic layered double hydroxide (MLDH) and fluorouracil (FU) components. The two-level supra-molecular MLDH-FU presented six-edge lozenge TEM morphology, with layered characteristics. DET on the surface of DMF was capable of protecting the layered structure of MLDH-FU, improving particle dispersion properties, and strengthening the slow-release performance of the drug delivery system. The drug release model of DMF at pH 7.35 of PBS in vitro fit to the zero-order kinetics equation C = 1.1716 x 10(-5) + 4.4626 x 10(-7) t. The drug delivery system DMF could transport drugs principally to in vivo target organs with a local effect, targeted specificity, and excellent circulation transshipment performance. The pharmacokinetic process of DMF presented multi-peak phenomenon with peak attenuation and cyclic growth. The peaks appeared at 0.25, 1, 3, 5 and 9 d separately after dosing intervention. The first peak process of DMF accorded with a pharmacokinetic equation of C(FU) = 14.34 e(-0.530t) + 36.04 e(-0.321t) + 24.18 e(-0.96t), and presented the characteristic of slow absorption and fast elimination. As for subsequent peak processes, half-life increased, bioavailability increased, and plasma clearance decreased. The highest peak value of DMF was 1/37 of original value of FU, and the relative bioavailability was 419% to original FU.
Animals ; Biological Availability ; Delayed-Action Preparations ; Dextrans ; chemistry ; Drug Carriers ; Female ; Fluorouracil ; administration & dosage ; chemistry ; pharmacokinetics ; Half-Life ; Hydroxides ; chemistry ; Magnetics ; Male ; Microscopy, Electron, Transmission ; Rats ; Rats, Sprague-Dawley ; Spectrophotometry, Infrared ; Thermogravimetry ; X-Ray Diffraction

OBJECTIVETo compare the long-term outcomes of patients receiving percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG), or medical therapy for treatment of chronic total coronary occlusion (CTO).

METHODSThe patients with CTO were selected from a consecutive cohort of patients who underwent coronary angiography (CAG) between 2008 and 2009. The patients with multiple CAG were excluded. The patients received treatments with PCI, CABG, or conservative medication therapy and were followed for major adverse cardiovascular events (MACE) within 5 years.

RESULTSA total of 253 patients were enrolled in this study, including 192 receiving PCI, 48 receiving CABG, and 13 treated conservatively with medications. The baseline clinical characteristics were similar among the 3 groups except for increased low-density lipoprotein (LDL) and total cholesterol (TC) in the medication group, and increased Syndax score in CABG group. During the follow-up, the incidences of MACE, AMI, death, stroke or heart failure did not differ significantly among the 3 groups (P>0.05). However, CABG group showed a higher incidence of the stroke than the other two groups although this difference did not reach a statistically significantly level (P=0.06).

CONCLUSIONOur study did not demonstrate that recanalization offers greater long-term benefits than medications for treatment of CTO, and the patients receiving CABG appeared to have a higher incidence of stroke.

Chronic Disease ; Cohort Studies ; Coronary Angiography ; Coronary Artery Bypass ; Coronary Occlusion ; surgery ; therapy ; Humans ; Incidence ; Percutaneous Coronary Intervention ; Stroke ; epidemiology ; Treatment Outcome

OBJECTIVETo explore the value of color doppler ultrasound examination of thyroid in occupational health care of radiation-exposed physicians.

METHODSOne hundred and thirty-four radiation-exposed physicians (observation group) and sixty-eight non-radiation-exposed physicians (control group) received color doppler ultrasound examination of thyroid using ALOKA SSD-4000 color doppler ultrasonic diagnostic apparatus, and the results were compared between the two groups.

RESULTSThe anteroposterior diameters of the left lobe, right lobe, and isthmus of the thyroid in the observation group were significantly larger than those in the control group (P < 0.01). Compared with the control group, the observation group had significantly larger internal diameters and peak blood flow velocities during systole of the right superior thyroid artery (P < 0.05, P < 0.05). There were no significant differences in detection rates of thyroid nodules and lymph nodes between the observation group and the control group (18.7% vs 13.2%, P > 0.05; 6.7% vs 1.5%, P > 0.05). The radiation-exposed physicians were exposed to low-dose ionizing radiation with a dose between 0.14 and 1.67 mSv/a.

CONCLUSIONThe color doppler ultrasound examination of the thyroid can detect early changes in the thyroid of radiation-exposed physicians exposed to long-term and low-dose ionizing radiation.

Humans ; Lymph Nodes ; Occupational Exposure ; analysis ; Occupational Health ; Physicians ; Radiation Exposure ; analysis ; Radiation, Ionizing ; Thyroid Gland ; diagnostic imaging ; radiation effects ; Ultrasonography, Doppler, Color

OBJECTIVETo explore the effect of recombinant human erythropoietin (rhEPO) on expression of brain-derived neurotrophic factor (BDNF) in different brain regions of aging rats.

METHODSForty male SD rats were randomized equally into negative control group, D-galactose group, EPO treatment group, and positive control group. Rat models of subacute aging were established by continuous subcutaneous injection of 5% D-galactose. Immunohistochemical staining was used to analyze the variation of BDNF expressions in different brain regions of the aging rats with different treatments.

RESULTSSignificant brain region-specific differences in BDNF expression were found among the rats in different groups. Compared with those in the negative control group, the numbers of BDNF-positive cells in the hippocampal CA1 region, CA3 region, dentate gyrus (DG) and frontal cortex were all decreased obviously in D-galactose group (P<0.05) but increased in both EPO group and the positive control group (P<0.05) without significant differences between the latter two groups. In the rats in the same group, the number of BDNF-positive cells varied markedly in different brain regions (P<0.05), and the expression level of BDNF was the highest in the frontal cortex followed by the hippocampal CA3 region and the dentate gyrus, and was the lowest in the hippocampal CA1 region.

CONCLUSIONTreatment with rhEPO enhances the expression of BDNF in rat neural cells, suggesting that rhEPO may protect the nervous system from aging by regulating the BDNF pathway.

Aging ; Animals ; Brain-Derived Neurotrophic Factor ; metabolism ; CA1 Region, Hippocampal ; metabolism ; CA3 Region, Hippocampal ; metabolism ; Dentate Gyrus ; metabolism ; Erythropoietin ; pharmacology ; Frontal Lobe ; metabolism ; Galactose ; Humans ; Male ; Neurons ; drug effects ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; pharmacology

The study was aimed to explore the mechanism of SYK and CBL family of ubiquitin ligases in Bufalin-induced HL-60 cells apoptosis. Cell viability was tested by trypan blue staining and apoptosis was detected by using flow cytometry. The expressions of CBL and CBL-b and the phosphorylation of SYK were detected by using immunoprecipitation and Western blot. The results showed that Bufalin inhibited HL-60 cell proliferation in time- and dose-dependent manners. IC(50) of suppressing cell viability at 24, 48 and 72 hours were about 26.3, 7.8 and 2.0 nmol/L respectively. The high dose of bufalin already induced apoptosis of HL-60 cells at 8 hours. SYK was quickly phosphorylated, and the expressions of CBL and CBL-b were down-regulated after treatment with Bufalin. It is concluded that SYK activation and CBL protein down-regulation may be involved in Bufalin-induced HL-60 cell apoptosis.
Apoptosis ; drug effects ; Bufanolides ; pharmacology ; Cell Proliferation ; drug effects ; Down-Regulation ; Gene Expression Regulation, Leukemic ; HL-60 Cells ; Humans ; Intracellular Signaling Peptides and Proteins ; metabolism ; Protein-Tyrosine Kinases ; metabolism ; Proto-Oncogene Proteins c-cbl ; metabolism ; Signal Transduction ; Syk Kinase

Acute lymphoblastic leukemia (ALL) is a malignant clonal disease, its treatment methods include chemotherapy, hematopoietic stem cell transplantation, immunotherapy and molecular targeted therapy. Clinically, ALL patients need to get complete remission through chemotherapy, and then choose the other treatment according to the patient's condition. But the drug resistance has been a biggest obstacle in treatment of ALL. There are many research reports about drug-resistant of ALL at present. In this review, the classic drug resistance mechanisms, such as membrane transporter, gene modifications and some newly finding mechanisms including such as bone marrow microenvironment and Micro RNA and so on are summarized.
Bone Marrow ; physiology ; Cellular Microenvironment ; Drug Resistance, Neoplasm ; Humans ; Membrane Transport Proteins ; physiology ; MicroRNAs ; genetics ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy