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In 2020, the prevalence of abnormal spinal curvature among 54 079 students in Shandong Province was 1.54%. The multivariate logistic regression model analysis showed that, compared with those in primary school, economically underdeveloped areas, and non-residential schools, students in middle and high schools, economically average areas, and residential schools had a higher risk of abnormal spinal curvature, with OR (95%CI) values of 2.029 (1.662-2.476), 2.746 (2.208-3.416), 2.237 (1.740-2.875) and 2.057 (1.705-2.483), respectively. Compared with those in economically underdeveloped areas, who were underweight, who had seat adjustments≤1 time per academic year, and who had physical education classes≤1 per week, students in economically developed areas, who were normal weight, overweight, and obese, who had seat adjustments≥2 times per academic year, and who had physical education classes 2-3 or≥4 per week, had a lower risk of abnormal spinal curvature, with OR (95%CI) values of 0.690 (0.521-0.915), 0.722 (0.546-0.955), 0.535 (0.389-0.735), 0.383 (0.274-0.535), 0.835 (0.711-0.980), 0.561 (0.474-0.663) and 0.491 (0.315-0.766), respectively.
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Humans , Risk Factors , Prevalence , Spinal Curvatures , Schools , StudentsABSTRACT
In 2020, the prevalence of abnormal spinal curvature among 54 079 students in Shandong Province was 1.54%. The multivariate logistic regression model analysis showed that, compared with those in primary school, economically underdeveloped areas, and non-residential schools, students in middle and high schools, economically average areas, and residential schools had a higher risk of abnormal spinal curvature, with OR (95%CI) values of 2.029 (1.662-2.476), 2.746 (2.208-3.416), 2.237 (1.740-2.875) and 2.057 (1.705-2.483), respectively. Compared with those in economically underdeveloped areas, who were underweight, who had seat adjustments≤1 time per academic year, and who had physical education classes≤1 per week, students in economically developed areas, who were normal weight, overweight, and obese, who had seat adjustments≥2 times per academic year, and who had physical education classes 2-3 or≥4 per week, had a lower risk of abnormal spinal curvature, with OR (95%CI) values of 0.690 (0.521-0.915), 0.722 (0.546-0.955), 0.535 (0.389-0.735), 0.383 (0.274-0.535), 0.835 (0.711-0.980), 0.561 (0.474-0.663) and 0.491 (0.315-0.766), respectively.
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Humans , Risk Factors , Prevalence , Spinal Curvatures , Schools , StudentsABSTRACT
@#Head and neck squamous cell carcinoma (HNSCC) is a common malignant tumor that seriously threatens human health and life. With increasing studies on the mechanism of tumor immune escape, programmed death receptor 1 (PD-1) and programmed death ligand receptor 1 (PD-L1) have been proven to be involved in tumor immune escape. The primary mechanism is that PD-1 recruits protein tyrosine phosphatase (SHP-2) to dephosphorylate downstream tyrosine kinase (SyK) and phosphatidylinositol 3-kinase (PI3K), thereby inhibiting downstream protein kinase B (AKT), extracellular regulated protein kinases (ERK) and other important signaling pathways, ultimately inhibiting T cell activation. In recent years, PD-1/PD-L1 inhibitors have become popular immunotherapies. Pembrolizumab and nivolumab have been approved for HNSCC patients by the U.S. Food and Drug Administration. Both durvalumab and atezolizumab are still in clinical trials, and published data show that both have certain safety and efficacy but still need much clinical data to support them. Meanwhile, the combination of PD-1/PD-L1 inhibitors with radiotherapy, chemotherapy and immunotherapy is still controversial in terms of clinical efficacy and adverse events, and further research is needed. However, serious immune-related adverse reactions limit the clinical application of PD-1/PD-L1 inhibitors, despite promising curative effects. Therefore, developing novel inhibitors and investigating stable and effective biomarkers and upstream and downstream signaling mechanisms are urgent issues.
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Objective@#To understand school physician in primary and secondary schools in Yichang City, Hubei Province from 2019 to 2020, and to provide a reference for strengthening the school physician team in primary and secondary schools.@*Methods@#149 and 102 primary and secondary schools from 6 municipal districts in Yichang City, Hubei Province, were randomly selected in November 2019 and November 2020, respectively, and were administered by questionnaire survey.@*Results@#The proportion of school physicians increased from 39.6% in 2019 to 65.7% in 2020. In the past two years, the equipment rate of school physician in both central and fringe urban areas increased, especially the fringe urban areas, number of school physician increased from 38 to 96. A total of 93 and 141 school physicians were selected to pariticipate in questionaire survey in 2019 and 2020 respectively. The survey showed that more than 90% of school physicians in primary and secondary schools in Yichang received training, and 74.5% had college education level. However, most of them lack professional qualification and medical background.@*Conclusion@#School physician of primary and secondary of Yichang is well development over the past two years, and the proportion substantially increased. However, there is still room for improvement in the quantity and quality of school physicians, and professional qualification needs to be improved. More attention should be paid to the marginal urban areas to achieve a balance between quantity and quality.
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Objective:To explore the safety of transanal re-excision (TAR) after positive-margin local resection for early rectal cancer.Methods:A retrospective analysis was made data of 44 patients with rectal cancer after local excision from Mar 2006 to Oct 2018 at the Department of Colorectal Surgery, Cancer Hospital of Chinese Academy of Medical Sciences. All patients had positive margin or suspicious tumor remains after local excision, and subsequently salvage TAR surgery was performed after informed consent was given.Results:Forty-four patients after local excision were with pathologically showed residual condition, including 26 cases of positive margin and 18 cases of suspicious tumor remaining. The pathological types were all adenocarcinoma. Forty-one (93%) patients with pT1 and 3 (7%) patients with pT2. The median follow-up time after salvage TAR was 100 (11-164) months. During follow-up, 3 patients (7%) developed mild anal incontinence. One patient (2%) had local recurrence, 3 (7%) patients had distant metastases, and 3 patients (7%) died of non-tumor specific deaths. The overall 5-year survival rate and disease-free survival rate were 98% and 93 %, respectively.Conclusions:Transannal full thickness tumor re-excision is safe and reliable for the salvage treatment after non-complete local resection of early rectal cancer. The long-term follow-up results show that the 5-year survival rate is comparable to that of radical surgical resection, and with a good anal function.
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Objective To analysis the correlation of serum clozapine concentration with serum homocysteine (Hcy) level and biochemical index in schizophrenic patients. Methods Two hundred and forty one schizophrenic patients treated with clozapine in Beijing Anding Hospital from January 1st 2017 to January 31st 2018 were enrolled in the study. Serum clozapine concentration, Hcy levels and biochemical index were measured. Patients were divided into high concentration group (n=41), normal concentration group (n=86) and low concentration group (n=114) according to serum clozapine concentration. The correlation of serum clozapine concentration with Hcy level and biochemical index was analyzed. Results The levels of Hcy, TG and LDL were higher in high clozazapine concentration group than in low concentration group and in normal concentration group (P<0.05). There was no significant difference between normal group and low concentration group in Hcy, TG and LDL levels (P>0.05). High serum clozapine concentration was positively correlated with serum Hcy (r=0.221, P=0.013), TG (r=0.193, P=0.003) and LDL level (r=0.148, P=0.021). Conclusion Serum levels of Hcy, TG and LDL in schizophrenic patients treated with clozapine are correlated with drug concentration, suggesting that patients with abnormally elevated levels of Hcy, TG and LDL should be monitored.
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Objective To investigate the safety and efficacy of enhanced recovery after surgery (ERAS) used in laparoscopic colorectal cancer surgery.Methods We conducted a retrospective analysis of the medical records of 99 cases treated with ERAS programed laparoscopic colorectal cancer surgery (ERAS group) and 103 cases treated with traditional perioperative care and laparoscopic colorectal cancer surgery (controlled group) from Mar 2017 to Sep 2017 in our center.Results There was no significant difference in age,gender,BMI,ASA classification,tumor location,operation time,pathological stage and the incidence of postoperative complications between ERAS group and controlled group (all P ＞ 0.05).Compared to control group,ERAS had less blood loss,shorter time to pass first flatus,stool and start diet and shorter hospitalization day,with all the difference statistically significant [(60 ± 63)ml vs.(112 ± 245)ml,(3.0±0.8)dvs.(4.3 ±1.2)d,(3.5 ±1.0)dvs.(4.6±1.3)d,(4.1 ±1.2)dvs.(5.4± 2.0)d,(5.8±2.1)dvs.(7.8±2.5)d,t=-2.021、-9.216、-6.887、-5.252、-6.163,allP＜ 0.05].No patients in both groups suffered from readmission or death within 30 days after surgery.Conclusion Patients treated with ERAS programed laparoscopic colorectal cancer surgery is safe and effective,with rapid recovery and reduced hospital stay.
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We proposed a new deep learning model by analyzing electroencephalogram signals to reduce the complexity of feature extraction and improve the accuracy of recognition of fatigue status of pilots. For one thing, we applied wavelet packet transform to decompose electroencephalogram signals of pilots to extract the δ wave (0.4-3 Hz), θ wave (4-7 Hz), α wave (8-13 Hz) and β wave (14-30 Hz), and the combination of them was used as de-nosing electroencephalogram signals. For another, we proposed a deep contractive auto-encoding network-Softmax model for identifying pilots' fatigue status. Its recognition results were also compared with other models. The experimental results showed that the proposed deep learning model had a nice recognition, and the accuracy of recognition was up to 91.67%. Therefore, recognition of fatigue status of pilots based on deep contractive auto-encoding network is of great significance.
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Summary Objective: Dermal papilla cells (DPCs) are located in the hair follicles and play an important role in hair growth. These cells have the ability to induce hair follicle formation when they display aggregative behavior. DPCs derived from the androgenetic alopecia (AGA) area undergo premature senescence in vitro, associated with p16INK4a expression. The aim of the current study was to investigate the expression of p16INK4a in aggregative and non-aggregative DPCs and the effect of p16INK4a down-regulation in these cells by adenovirus-mediated RNA interference (RNAi). Method: DPCs were isolated and cultured from healthy human scalp. p16INK4a gene and protein were detected in aggregative and non-aggregative cells. Expression of p16INK4a in DPCs was silenced by infection with rAd5-CDKN1A-1p2shRNA. Cell fate was monitored after infection. The growth of cells was measured by MTT assay. Cell cycle was evaluated by flow cytometry (FCM). Results: DPCs were isolated by digestion and showed aggregative behavior for six passages. The expression of p16INK4a showed a clear upward trend in non-aggregative cells when compared with aggregative group. p16INK4a expression was silenced by rAd5-CDKN1A-1p2shRNA (p<0.05). The p16INK4a-silenced cells grew more rapidly and exhibited a trend towards aggregative growth. There was an increase in the proportion of cells in G1 phase, while those in S phase were reduced after p16INK4a gene silencing (p<0.05). Conclusion: Our results suggest that p16INK4a plays an important role in the premature senescence and aggregative behavior of DPCs. These observations can lead to novel therapeutic strategies for treatment of AGA.
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Humans , Male , Scalp/cytology , Hair Follicle/cytology , Genes, p16/physiology , Reference Values , Time Factors , Immunohistochemistry , Transfection , Cell Aggregation/genetics , Cell Cycle/genetics , Cells, Cultured , Cellular Senescence/genetics , Dermis/cytology , Reverse Transcriptase Polymerase Chain Reaction , Cell Proliferation/genetics , Alopecia/genetics , Gene Knockout Techniques/methods , Flow CytometryABSTRACT
Excessive reactive oxygen species (ROS) is associated with an array of pathological conditions, including cancer, diabetes, cardiovascular diseases, and neurodegenerative diseases. However, ROS-responsive materials have drawn attention in the development of drug delivery systems. There are many types of ROS-responsive materials explored in drug delivery applications, including sulfur-based responsive polymers, selenium-based responsive polymers, tellurium-based responsive polymers, oxalate ester-containing polymers, phenylboronic ester-containing polymers and unsaturated lipids. When integrated with ROS-responsive drug delivery systems, a photosensitizer is used as a light-sensitive element to generate ROS, mainly singlet oxygen (1O2), which in turn activates the ROS-triggered drug delivery.
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Photo-sensitive reactive oxygen species (ROS) responsive liposomes loaded with 1,4,8,11,15, 18,22,25-octabutoxypalladium phthalocyanine[PdPC(OBu)8] and doxorubicin hydrochloride (DOX) (LPD) were prepared by (NH4)2SO4-gradient method. LPD was characterized with transmission electron microscopy (TEM), dynamic light scattering particle size, zeta potentials, photo-sensitive ROS-responsive DOX release behaviors and the serum stability in vitro. LPD cytotoxicity, DOX uptake and singlet oxygen production in MCF-7 cells were evaluated. The results showed that the particle size of LPD was (169.3 ±1.2) nm, PDI of LPD was 0.198 ±0.003 and zeta potentials of LPD was (-39.8 ±0.8) mV. The accumulated release of DOX reached 95.5% in 5 min under 730 nm laser irradiation (300 mW·cm-2). The DOX uptake of liposome was increased and 1O2 was generated. The half inhibition concentration (IC50) of DOX in LPD with irradiation group was decreased by 85.7% and no irradiation group was decreased by 67.9% compared with free DOX group in MCF-7 cells. Therefore, photo-sensitive ROS-responsive liposomes would be a promising drug delivery system for tumor therapy.
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Platycodin D (PD), a triterpenoid saponin isolated from Platycodonis Radix, is a famous Chinese herbal medicine that has been shown to have anti-proliferative effects in several cancer cell lines. The aim of this study was to determine the changes in cellular proteins after the treatment of hepatocellular carcinoma HepG2 cells with PD using proteomics approaches. The cell viability was determined using the MTT assay. The proteome was analyzed by two-dimensional difference gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Western blot analysis was used to confirm the expression of changed proteins. Our results showed that PD inhibited the proliferation of HepG2 cells in concentration- and time-dependent manners. Sixteen proteins were identified to be up-regulated in PD-treated HepG2 cells, including ATP5H, OXCT1, KRT9, CCDC40, ERP29, RCN1, ZNF175, HNRNPH1, HSP27, PA2G4, PHB, BANF1, TPM3, ECH1, LGALS1, and MYL6. Three proteins (i.e., RPS12, EMG1, and KRT1) decreased in HepG2 cells after treatment with PD. The changes in HSP27 and PHB were further confirmed by Western blotting. In conclusion, our results shed new lights on the mechanisms of action for the anti-cancer activity of PD.
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Humans , Antineoplastic Agents, Phytogenic , Pharmacology , Therapeutic Uses , Apoptosis , Blotting, Western , Campanulaceae , Chemistry , Carcinoma, Hepatocellular , Drug Therapy , Metabolism , Cell Proliferation , Cell Survival , Hep G2 Cells , Liver Neoplasms , Drug Therapy , Metabolism , Phytotherapy , Plant Extracts , Pharmacology , Therapeutic Uses , Proteome , Metabolism , Proteomics , Saponins , Pharmacology , Therapeutic Uses , Triterpenes , Pharmacology , Therapeutic Uses , Up-RegulationABSTRACT
High-density channels are often used to acquire electroencephalogram (EEG) spatial information in different cortical regions of the brain in brain-computer interface (BCI) systems. However, applying excessive channels is inconvenient for signal acquisition, and it may bring artifacts. To avoid these defects, the common spatial pattern (CSP) algorithm was used for channel selection and a selection criteria based on norm-2 is proposed in this paper. The channels with the highest M scores were selected for the purpose of using fewer channels to acquire similar rate with high density channels. The Dataset III a from BCI competition 2005 were used for comparing the classification accuracies of three motor imagery between whole channels and the selected channels with the present proposed method. The experimental results showed that the classification accuracies of three subjects using the 20 channels selected with the present method were all higher than the classification accuracies using all 60 channels, which convinced that our method could be more effective and useful.
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Humans , Algorithms , Brain-Computer Interfaces , Electroencephalography , Pattern Recognition, PhysiologicalABSTRACT
BACKGROUND:Novel fuly biodegradable poly-L-lactic acid/amorphous calcium phosphate (PLLA/ACP) scaffold shows a good prospect of application, but whether the scaffold material has impact on the surrounding tissue calcification is unknown. OBJECTIVE: To observe the influence of PLLA/ACP scaffold material on the calcification of surrounding tissue after implantation of PLLA/ACP scaffold into rats. METHODS:A total of 48 SD rats were divided into experimental group and control group randomly. The experimental group was implanted with PLLA/ACP scaffold material, while the control group was implanted with PLLA scaffold material. At 1, 2, 4, 12 weeks after implantation, the liver function, kidney function and concentrations of calcium, phosphorus, alkaline phosphatase in serum were detected; the muscle tissue around the scaffold was colected for hematoxylin-eosin staining, Von Kossa staining, alkaline phosphatase staining and immunohistochemical staining of nuclear factor-kappa B. Then, western blot assay was used to detect the contents of interleukin-6, bone morphogenetic protein-2, and meanwhile, the contents of calcium and alkaline phosphatase in tissue homogenate were measured. RESULTS AND CONCLUSION:There was no significant difference in either group about the liver and kidney functions at each time. The content of interleukin-6 in the experimental group was less than that in the controlgroup at 2, 4 and 12 weeks after implantation (P 0.05). These findings indicate that the PLLA/ACP scaffold has a good biocompatibility and biological security, which cannot induce peripheral tissue calcification.
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<p><b>OBJECTIVE</b>To discuss the intervention effect of ligustrazine on ox-LDL-induced foam cells from the perspective of reverse cholesterol transport.</p><p><b>METHOD</b>RAW264.7 cultured in vitro was induced with 20 mg x L(-1) ox-LDL to establish the foam cell model, and intervened with ligustrazine. The lipid accumulation in cells was observed by the oil red O dyeing. The changes in total cholesterol and cholesterol ester in the cells were detected with the colorimetric method. The fluorescent quantitative PCR and Western blot were used to detect the mRNA expressions of PPARgamma, LXRalpha and ABCA1.</p><p><b>RESULT</b>Ligustrazine could reduce total cholesterol and cholesterol ester in foam cells, inhibit the lipid accumulation, and increase the mRNA and protein expressions of PPARgamma, LXRalpha and ABCA1.</p><p><b>CONCLUSION</b>Ligustrazine can promote the reverse cholesterol transport by increasing the gene expressions of PPARgamma, LXRalpha and ABCA1.</p>
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Animals , Mice , ATP Binding Cassette Transporter 1 , Genetics , Metabolism , Biological Transport , Cell Line , Cholesterol , Metabolism , Drugs, Chinese Herbal , Pharmacology , Foam Cells , Metabolism , Gene Expression , PPAR gamma , Genetics , MetabolismABSTRACT
BACKGROUND:In order to solve the problems of poly-l-lactic acid (PLLA) stents, such as poor support, acidic metabolites, we researched a novel biogradable stent-PLLA/amorphous calcium plosphate (ACP). OBJECTIVE: To discuss the safety and histocompatibility of the novel biogradable stent-PLLA/ACP stent implanted in the coronary artery in a porcine model. METHODS:Sixteen novel biogradable stents were randomly implanted into the coronary arteries, left anterior descending branch, left circumflex artery or right coronary artery of sixteen healthy Tibet miniature pigs. The blood routine and blood biochemistry were measured pre-operation and at 1 month after operation. The coronary blood vessels where the stent was implanted were examined by hematoxylin-eosin staining at 1 and 6 months after operation. RESULTS AND CONCLUSION: Compared with pre-operation, the post-operation indicators of the blood routine and blood biochemistry were of no significant difference. Coronary angiography revealed coronary artery patency and no thrombosis, the vascular stent segments exhibited clear boundaries with the surrounding tissue, with no tissue adhesion, necrosis, and adherence abnormalities. The results of hematoxylin-eosin staining showed that there was no significant difference in vascular injury integral between 1 month after operation and 6 months after operation. However, 6 months after operation, the scores of the inflammation were lower (P < 0.05), and the scores of the endothelialization were increased (P < 0.05). There was no myocardial infarction and inflammatory cellinfiltration around the stent. These results suggest that the novel biodegradable stent has good safety and histocompatibility.
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In the 1960s, modern science began involving the essence of heat syndrome, but there have still no in-depth systematic studies on pathological mechanisms of heat syndrome and action mechanisms of cold and cool herbs. In this study, the animal model with heat syndrome was set up by feeding herbs with hot property, and then cold and cool herbs was applied in the experimental therapy. The two-dimensional electrophoresis and mass spectrometry technologies were adopted to compare the liver mitochondria proteome of the rats of the heat syndrome model and the ones treated with cold and cool herbs, so as to discover specificity-related proteins after heat syndrome and treatment with cold and cool herbs.
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Animals , Male , Rats , Carbohydrate Metabolism , Cold Temperature , Drugs, Chinese Herbal , Pharmacology , Energy Metabolism , Hot Temperature , Lipid Metabolism , Mitochondria, Liver , Metabolism , Proteome , Metabolism , Rats, Sprague-DawleyABSTRACT
<p><b>OBJECTIVE</b>To study eleven organophosphorus insecticides residuals in four kinds of Chinese crude drugs.</p><p><b>METHOD</b>The organophosphorus insecticides were extracted with dichloromethane and cleaned-up with a mixture of Celite 545-activated carbon. The extracts were analyzed by gas chromatography equipped with a flame photometric detector (FPD).</p><p><b>RESULT</b>Analysis of fortified Chinese crude drug showed that the average recoveries ranged from 77.5% -112.3% at three different levels, the RSDs were below 10% (n = 4). Trace organophosphorous pesticide residues were found in samples of Rhizoma Atractylodis Macrocephalae and Flos Chrysanthemi.</p><p><b>CONCLUSION</b>A method was established for determination multi-residues in Rhizma Atractylodis Macrocephalae, Radix Curcumae, Bulbus Fritillariae Thunbergii and Flos Chrysanthemi. It provides a method for the risk assessment of organophosphorous pesticide in Chinese crude drugs.</p>
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Atractylodes , Chemistry , Chromatography, Gas , Chrysanthemum , Chemistry , Curcuma , Chemistry , Drug Contamination , Drugs, Chinese Herbal , Chemistry , Fritillaria , Chemistry , Organophosphorus Compounds , Pesticide Residues , Plants, Medicinal , ChemistryABSTRACT
This study is to evaluate the cytotoxicity of mitomycin C (MMC) and its analogue 5-(aziridin-1-yl)-3-hydroxymethyl-1-methylindole-4,7-dione (629) as well as the effect of transfection of constitutive androstane receptor (CAR) on their biological effects. HepG2 cells were transfected with the plasmids mCAR1/pCR3 mediated by liposome. Vector pCR3 was used as control. Transfected cells were screened by G418 resistance and limiting dilution. The expressions of plasmid mCAR1/pCR3 and CYP2B6 mRNA were detected by RT-PCR; Cytotoxicities of MMC and 629 in vitro were evaluated in g2car cells and HepG2 cells by MTT method under anaerobic and aerobic conditions. mRNA expression of CAR and CYP2B6 can not be detected in HepG2 cells and HepG2/pCR3 cells but can in g2car cells. It is shown that plasmid mCAR1/pCR3 was transfected into g2car cells successfully and target CYP2B6 was transactivated by CAR. To compare with aerobic and anaerobic, the cytotoxicities of MMC and 629 to HepG2 cells and g2car cells had significantly enhanced (P < 0.05), and transfect CAR gene can improve the cytotoxicity of MMC (P < 0.05), but not 629 (P > 0.05). Furthermore, CYP2B6 is one master enzyme for the metabolism of MMC and not 629. Transfection of CAR can increase expression of CYP2B6 mRNA in HepG2 cells, and can affect cytotoxicities of MMC and 629.
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Humans , Antibiotics, Antineoplastic , Pharmacology , Aryl Hydrocarbon Hydroxylases , Genetics , Aziridines , Pharmacology , Carcinoma, Hepatocellular , Metabolism , Pathology , Cell Death , Cell Hypoxia , Cell Line, Tumor , Cytochrome P-450 CYP2B6 , Indoles , Pharmacology , Inhibitory Concentration 50 , Liver Neoplasms , Metabolism , Pathology , Mitomycin , Pharmacology , Oxidoreductases, N-Demethylating , Genetics , Plasmids , RNA, Messenger , Metabolism , Receptors, Cytoplasmic and Nuclear , Genetics , Recombinant Proteins , Genetics , Transcription Factors , Genetics , TransfectionABSTRACT
<p><b>AIM</b>To examine the effect of inducible nitric oxide synthase (iNOS) on tumour cells chemosensitivity to mitomycin C (MMC) analogue 5-aziridinyl-3-hydroxyl-1-methylindole-4,7-dione (629) in vitro, and elucidate the possible role of iNOS in the metabolism of 629.</p><p><b>METHODS</b>Human sarcoma cells (HT1080) and its iNOS gene transfected clones (iNOS9, iNOS12) were exposed to 629 at concentrations of 1 nmol x L(-1) - 100 micromol x L(-1). 3-[4, 5-Dimethylthiazol-2-yl] -2,5-diphenyltetrazolium bromide (MTT) assay, agarose electrophoresis and flow cytometric analysis were used to determine cell sensitivity, deoxyribonucleic acid (DNA) damage and the change of cell cycle in above process, respectively. All experiments were performed both in air and under hypoxia parallelly.</p><p><b>RESULTS</b>629 was more toxic than MMC, and enhanced cytotoxicity under hypoxia, which resulted in cell necrosis. Sixteen hours after treated with 629, HT1080 cells and related iNOS-transfected clone cells were obviously blocked in G2/M phase.</p><p><b>CONCLUSION</b>iNOS plays dual roles in 629 metabolism, enhancing or decreasing the cytoxicity of 629 depending on the intracellular oxygen pressure P(O2), which caused higher cytotoxicity to hypoxia cells of 629 with the increasing of iNOS activity.</p>