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find Keyword "resistance" 187 results
  • Molecular mechanism of metastasis-associated protein 3 involvement in glioma drug resistance through reactive oxygen

    ObjectiveTo investigate the molecular mechanism by which metastasis-associated protein 3 (MTA3) participates in glioma resistance through reactive oxygen species. Methods Protein expression in glioma stem cells (GSCs) and non-GSCs was detected using Western blotting. GSCs included U87 and SHG44 cells, while non-GSCs included U87s and SU-2 cells. After overexpressing MTA3, U87 and SHG44 cells were divided into Lv-scr and Lv-MTA3 groups. The self-renewal capacity of glioma cells was assessed through a neurosphere formation assay. Cell survival fractions were examined following exposure to 0, 2, 4, 6, 8, and 10 Gy X-ray irradiation under normoxic or hypoxic conditions. Apoptosis and reactive oxygen species expression were analyzed using flow cytometry. Immunofluorescence staining was performed to detect the stem cell markers CD133 and nestin, as well as the differentiation markers glial fibrillary acidic protein (GFAP, for astrocytes) and neuronal class Ⅲ β-tubulin. Results In GSCs, MTA3 expression was lower in the U87s and SU-2 groups. After MTA3 overexpression, Lv-MTA3 expression was higher in U87s and SU-2 compared to the Lv-scr group. Under normoxic or hypoxic conditions, U87 and SU-2 showed greater radioresistance compared to glioma cell lines U87 and SHG44. Compared to non-GSCs, basal reactive oxygen species formation was reduced in GSCs, while reactive oxygen species generation was increased in non-GSCs. Following exposure to different doses of X-rays under normoxic or hypoxic conditions, GSCs with MTA3 overexpression exhibited greater radiosensitivity than those with stable integration. Additionally, MTA3 overexpression slightly increased the oxygen enhancement ratio (OER) in GSCs. MTA3 overexpression reduced the immunoreactivity of CD133 and nestin in both stem cell lines, and increased immunofluorescence staining of GFAP and neuronal class Ⅲ β-tubulin, with statistically significant differences (P<0.05). Conclusions MTA3 is downregulated in GSCs. Overexpression of MTA3 reduces the radioresistance and stemness of GSCs both in vitro and in vivo. MTA3 plays a crucial role in regulating the radiosensitivity and stemness of GSCs through reactive oxygen species.

    Release date:2024-06-24 02:56 Export PDF Favorites Scan
  • REVERSAL OF MULTIDRUG RESISTANCE OF HUMAN HEPATOMA RESISTANT CELLS IN VITRO BY ANTISENSE PHOSPHOROTHIOATE OLIGONUCLEOTIDE

    Objective To investigate the reversal effect of antisense phosphorothioate oligonucleotide (ASOND) on human hepatoma resistant cells. Methods Human hepatoma resistant cells SMMC-7721 was transfected with synthetic antisense phosphorothioate oligonucleotide complementary to the 5′ region flanking the AUG initiation codon mediated by lipofectamine. In vitro drug sensitivity was measured by MTT assay. The expression of P-170 was determined by flow cytometry and mRNA was assessed by RT-PCR. Results ASOND inhibited the expression of mRNA and p-170 in SMMC-7721, enhanced the sensitivity of SMMC-7721 to chemotherapeutic drug. The best inhibitory effect was achived by the dose of 0.5μmol/L. Conclusion ASOND enhanced the sensitivity of SMMC-7721 to chemotherapeutic drug and reversed the multidrug resistance of SMMC-7721 partially.

    Release date:2016-08-28 05:30 Export PDF Favorites Scan
  • Research Progress of The Relationship Between The Insulin Resistance, IGF-Ⅰ, IGF-Ⅱ, and Colorectal Cancer

    ObjectiveTo review the research progress of the relationship between the insulin resistance, insulin-like growth factor-Ⅰ(IGF-Ⅰ), insulin-like growth factor-Ⅱ(IGF-Ⅱ), and colorectal cancer, and to explore the future research trends. MethodsThe related literatures in recent 5 years from abroad databases (PubMed, Web of Science, and EMBASE)and domestic databases (CNKI, WANFANG, and WEIPU)were collected and reviewed. ResultsThe research on the correlation between the changes and colorectal cancer with insulin resistance and IGF-Ⅰand IGF-Ⅱlevels, epidemiological studies and the mechanism research, indicates that there are complex and close relationship between them. ConclusionsThe research about the relationship between the insulin resistance, IGF-Ⅰ, IGF-Ⅱ, and colorectal cancer is promising.However, many issues need to be further investigated.

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  • Changes of Airway Resistances before and after Bronchial Dilation Test in COPD and Asthma

    Objective To explore the profile and diagnosis value of airway resistances before and after bronchial dilation test ( BDT) in patients with COPD and asthma. Methods Airway resistances before and after BDT were measured in COPD patients and asthma patients with different severity by impulse oscillometry ( IOS) , and the characteristic changes of the two different diseases were analyzed compared with healthy subjects. Results Airway resistance indexes except X5 were higher in the COPD and the asthma patients than those in the healthy subjects before BDT ( P lt; 0. 05) . There were significant differences in airway resistance indexes except X5 and Rc between the mild asthma patients and the moderate to severe asthma patients. Significant difference in Z5, Fres, and Rp were observed in the mild COPD patientscompared with the moderate to severe COPD patients. There were statistical differences in airway resistance indexes except X5 between the two groups before and after BDT both in the COPD and the asthma patients ( P lt;0. 05) . The rates of change in Z5, Fres, R5, and Rp were higher than those of FEV1% pred, especially higher in the asthma patients than in the COPD patients ( P lt; 0. 05) . Significant negative correlations between FEV1% pred and Z5, Fres, R5, Rp were revealed in the COPD and the asthma patients ( P lt;0. 01) .The correlation between Fres and FEV1% pred was most significant in the COPD and the asthma patients ( r = - 0. 561, - 0. 761) . Conclusion Airway resistances measured by IOS is sensitive indicators in detecting the airflow obstruction in COPD and asthma, and is useful in early and differential diagnosis of COPD and asthma.

    Release date:2016-08-30 11:53 Export PDF Favorites Scan
  • The epidemiological characteristics of the lung infection after liver transplantation

    Objective To explore the clinical epidemiological characteristics of the lung infection after orthotopical liver transplantation. Methods The clinical data included infection morbidity, mortality, infectious times and relative factors, clinical manifestations, the bacterial strains and distributions of the pathogens, the bacterial resistances of the 53 liver transplantation recipients from 2003.3~2006.12 were summarized and analyzed retrospectively. Results Among 53 recipients, 33 developed lung infectious and 6 died .The mobidity was 62.3% and mortality was 18.2%, with a OR of 1.0. Lung infection predominantly occurred in the first month, especially in the first week after transplantation.There were many factors related to lung infections.Various pathogens, especially Klebsialla, Escherichia Coli and Staphylococus Hominis were isolated from sputum, airway suction drainages and throat swabs. Most of the G- bacteria were sensitive to aminoglycosides,β lactam and lactamase compounds and carbapenems while G+ bacteria were sensitive only to glycopeptides. All the bacteria were resistant to quinolones, β lactams of third and forth generation. Conclusions After liver transplantation, the morbidity and mortality of the lung infections are high.The infections develope at earlier stage, manifest nontypical clinical features.Many factors are revealed to be relevant to the lung infections,meanwhile, various drug-resistant pathogen strains are isolated.

    Release date:2016-09-14 11:52 Export PDF Favorites Scan
  • Finite-element Investigation on Center of Resistance of Maxillary Anterior Teeth

    A three-dimensional finite element model of premaxillary bone and anterior teeth was established with ANSYS 13.0. The anterior teeth were fixed with strong stainless labial archwire and lingual frame. In the horizontal loading experiments, a horizontal retraction force of 1.5 N was applied bilaterally to the segment through hooks at the same height between 7 and 21 mm from the incisal edge of central incisor; in vertical loading experiments, a vertical intrusion force of 1.5 N was applied at the midline of lingual frame with distance between 4 and 16 mm from the incisal edge of central incisor. After loading, solution was done and displacement and maximum principle stress were calculated. After horizontal loading, lingual displacement and stress in periodontal membrane (PDM) was most homogeneous when the traction force was 14 mm from the edge of central incisor; after vertical loading, intrusive displacement and stress in PDM were most homogeneous when the traction force was 12 mm from the incisal edge of central incisor. The results of this study suggested that the location of center of resistance (CRe) of six maxillary anterior teeth is about 14 mm gingivally and 12 mm lingually to incisal edge of central incisor. The location can provide evidence for theoretical and clinical study in orthodontics.

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  • Homogeneous Analysis of Multidrug Resistant Acinetobacter baumannii in Emergency Intensive Care Unit

    Objective To investigate the drug resistance and homogeneous analysis of Acinetobacter baumanii in emergency intensive care unit ( EICU) . Methods Four multidrug-resistant Acinetobacter baumannii ( MDR-Ab) strains isolated fromnosocomial inpatients fromJuly 25 to September 7 in 2009 were collected and tested for drug sensitivity and MIC determination as well. The A. baumannii isolates were typed with pulsed-field gel electrophoresis ( PFGE) to determine whether they derived fromthe same clone.Results Four isolates from nosocomial inpatients were resistant to multiple antibiotics including carbapenem. The PFGE types identified from four isolates were A and B. The A. baumannii isolates did not derived from the same clone. Conclusion The prevalence of nosocomial infection is not due to transmission of the same strains among different individuals in EICU.

    Release date:2016-08-30 11:56 Export PDF Favorites Scan
  • Effects of resveratrol on multidrug resistance in human retinoblastoma cells

    Objective To observe the effect of resveratrol on multidrug resistance (MDR) in human retinoblastoma cells treated. Methods RB cells in logarithmic growth phase were divided into experimental group and control group. RB cells in experimental group were cultured with different concentrations of resveratrol (6.25, 12.50, 25.00, 50.00, 100.00 mu;mol/L) for 24 and 48 hours. The proliferation (absorbance value) was assayed using methyl thiazolyl tetrazolium (MTT). RB cells were cultured with 50.00 mu;mol/L resveratrol for 48 hours. The expressions of MDR-1, cyclooxygenase-2 (COX-2)、multidrug resistance-associated protein-1 (MRP-1), glutathione-S-transferases-pi; (GST-pi;) were determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The RB cells of the control group were cultured with 0.5% dimethyl sulfoxide. Results Compared with the control group, the absorbance value decreased in experimental groups (6.25, 12.50, 25.00, 50.00 mu;mol/L) in a dose dependent manner (F=4.782,P<0.05). The difference of absorbance value between 50.00 and 100.00 mu;mol/L experimental groups was not significant (F=6.351,P>0.05). Compared with the control group, the mRNA (t=9.170, 5.758, 4.152, 4.638) and protein (t=3.848, 5.955, 4.541, 3.514) expression levels of MDR-1, MRP1, COX-2, and GST-pi; decreased in the experimental group (P<0.05). Conclusion Resveratrol can down-regulate the expression of MDR in RB cells.

    Release date:2016-09-02 05:26 Export PDF Favorites Scan
  • Characteristics and drug resistance changes of carbapenem-resistant Klebsiella pneumoniae in different types of departments

    Objective To investigate the clinical characteristics and drug resistance changes of nosocomial infection caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) in different types of clinical departments, and to provide evidence for prevention and control of CRKP infection. Methods The hospital infection real-time monitoring system was used to retrospectively collect the inpatients with CRKP nosocomial infection in the First People’s Hospital of Lianyungang from January 2019 to December 2023 as the research objects. According to the different sources of departments, they were divided into intensive care unit (ICU) group, internal medicine group and surgery group. The changes of clinical characteristics and drug resistance to common antibiotics were analyzed. Results A total of 636188 inpatients were monitored, and 225 cases were infected with CRKP, with an overall infection detection rate of 0.035%. The detection rates of CRKP infection in the ICU group, internal medicine group, and surgery group were 0.736% (138/18749), 0.013% (44/336777), and 0.015% (43/280662), respectively, with the ICU group demonstrating a significantly higher rate than the other groups (P<0.05). The detection rates fluctuated in the early stage and then decreased rapidly in different years. The main infection site of CRKP in all groups was lower respiratory tract, but the proportion of device-related infections in the ICU group was higher than that in the internal medicine and surgery groups (P<0.05). In terms of the infected population, there was no significant difference in gender among groups (P>0.05) with the proportion of males more than 60%, while the difference in the proportion of patients aged ≥65 years among groups was statistically significant (P<0.05), with the highest in the internal medicine group (86.36%). The burden of underlying diseases and invasive operation exposure of the infected patients were high, and the proportion of cardiovascular and cerebrovascular diseases and indwelling catheters were as high as 69.33% and 83.56%, respectively. The differences in the proportions of cardiovascular and cerebrovascular diseases, diabetes mellitus, ≥3 underlying diseases, and surgical and invasive procedures among groups were statistically significant (P<0.05). The distribution of infection specimens in each group showed no statistically significant difference (P>0.05), with sputum, blood, and mid-stream urine specimens being the main detected specimens in all groups. The resistance rates of CRKP to penicillins and cephalosporins were more than 93%, and the resistance rates to aminoglycosides and sulfonamides were relatively low and showed a decline year by year. The resistance rate to ceftazidime/avibactam was only 7.41%, but the resistance rate to tigecycline increased. The difference in resistance rate of CRKP to co-trimoxazole among groups was statistically significant (P<0.05), while the differences in resistance to other antimicrobial agents were not statistically significant (P>0.05). Conclusions The detection rate, clinical characteristics and drug resistance of CRKP infection in different types of departments of medical institutions are different and changing. It is necessary to strengthen the rational use of antibiotics and the prevention and control of nosocomial infection.

    Release date:2025-03-31 02:13 Export PDF Favorites Scan
  • Relation between Diabetes and Pedopathy of Type II Diabetes and Insulin Resistance

    摘要:目的:探讨2型糖尿病合并糖尿病足患者与胰岛素抵抗的关系。方法:205例2型糖尿病患伴糖尿病足患者作为观察组,无足部病变的糖尿病患者作为对照组,观察其体重指数、空腹血糖、胰岛素、血脂等指标,两组间进行比较并相关性分析、多元回归分析。胰岛素抵抗指数(HOMAIR)=FPG×FIns/22.5。结果:糖尿病足患者的HOMAIR显著高于无糖尿病的患者(Plt;0.05)。多元回归分析显示糖尿病病程、LDL及BMI是影响2型糖尿病足患者胰岛素抵抗的主要危险因素。结论:糖尿病足患者存在着更严重的胰岛素抵抗。Abstract: Objective: To discuss the relationship between diabetes and pedopathy of type II diabetes and insulin resistance. Methods:The diabetes type II patients were divided into group A (combined with pedopathy) and group B (without pedopathy). The blood glucose and insulin of empty stomach, BMI,Alc and lipid were detected. The insulin resistance index (HOMAIR) was calculated and compared between two groups. Results:The HOMAIR was higher in group A than that in group B (Plt;0.05).The duration of disease,LDL and BMI was positive related with diabetes pedopathy. Conclusion:The insulin resistance was more worse in pedopathy of Type II diabetes.

    Release date:2016-09-08 10:12 Export PDF Favorites Scan
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