Objective To review the application advancements of ATP-binding cassette (ABC) transporter in medical research.Methods Relevant literatures about the applications of ABC families in medical research were reviewed. Results ABC families mainly took roles in transporting substances across cell membrane. Some of them were useful for the prediction of drug resistance and the prognosis of malignant tumors. Others were target s for molecular researches. Their expressions or mutations might be related with the occurrence of diseases. Conclusion ABC families are very important in the diagnosis and therapy for diseases. Thus they are very promising tools for future medical research.
摘要:目的:探討2型糖尿病合并糖尿病足患者與胰島素抵抗的關系。方法:205例2型糖尿病患伴糖尿病足患者作為觀察組,無足部病變的糖尿病患者作為對照組,觀察其體重指數、空腹血糖、胰島素、血脂等指標,兩組間進行比較并相關性分析、多元回歸分析。胰島素抵抗指數(HOMAIR)=FPG×FIns/22.5。結果:糖尿病足患者的HOMAIR顯著高于無糖尿病的患者(Plt;0.05)。多元回歸分析顯示糖尿病病程、LDL及BMI是影響2型糖尿病足患者胰島素抵抗的主要危險因素。結論:糖尿病足患者存在著更嚴重的胰島素抵抗。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 (HOMAIR) was calculated and compared between two groups. Results:The HOMAIR was higher in group A than that in group B (Plt;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.
Objective To review the recent studies on the multidrug resistance of breast cancer. Methods The literatures of recent years on the studies of multidrug resistance, multidrug resistance protein and breast cancer resistance protein were reviewed. Results Multidrug resistance resulted from multiple factors. How to identify the sensibility of chemotherapy drugs and select individual therapeutic regime early were important to improve the survival rate and life quality of breast cancer patients. Conclusion These studies on multidrug resistance of breast cancer are helpful to predicting the effect and outcome of chemotherapy and overcoming the barrier of drug resistance.
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.
ObjectiveTo describe the research progress of long non-coding RNA (lncRNA) and gastric cancer in recent years, and to make reasonable prospect for future research direction.MethodWe collected a large amount of literatures on lncRNA and gastric cancer at home and abroad, and sort out various kinds of lncRNA, to make an in-depth interpretation of the relationship between lncRNA and gastric cancer and the mechanism of action, and then clarified the latest research progress.ResultsAt present, the molecular mechanism of the occurrence and development of gastric cancer had not been fully elucidated, but current studies had shown that lncRNA (H19, HOTTIP, UCA1, MEG3, MALAT1, HULC, HOTAIR, GAPLINC, and so on) had regulatory effects at multiple levels such as epigenetics, transcription, translation, chemoresistance, and more and more lncRNA had been discovered closely related to gastric cancer.ConclusionlncRNA is closely related to the occurrence and development of gastric cancer and may be a key target for the treatment of gastric cancer in the future.
ObjectiveTo evaluate the effect of neoadjuvant chemotherapy and find the mechanism of multidrug resistance. MethodsTwenty patients with gastric cancer and 31 patients with colorectal cancer underwent neoadjuvant chemotherapy and then operations. The preoperative specimens were stained by immunohistochemical techniques for testing p53,multidrug resistanceassociated protein (MRP), glutathione S transferase（GST）, telomerase. Resection specimens were evaluated for chemotherapy effect by routine histology; at the same time, the postoperative morbidity and mortality were observed. ResultsIn 51 patients, the response rate of neoadjuvant chemotherapy was 27.45%(14/51),so multidrug resistance was a kind of common phenomena in gastrointestinal carcinomas. The postoperative morbidity was 15.69%(8/15), the main operation complication was infection,the mortality was 1.96%(1/51),only one person died from severe infection.The expression rate of p53, MRP, GST, telomerase was 58.0%,51.0%,66.7%,74.0%respectively, the location of p53 was at cell nucleus,location of MRP,GST was at cell memberane and cytoplasm,location of telomerase was at cytoplasm.The response rate had nothing to do with age, sex and metastasis. But it was related with p53 and telomerase expression. ConclusionNeoadjuvant chemotherapy is an effective, safe therapy. But the rate of drug resistance is high in gastrointestinal carcinomas, and the response rate is related to p53, telomerase expression.
Objective To assess the tolerance of preoperative carbohydrate-rich beverage, to determine its effect on postoperative insulin resistance and analyze its potential mechanism. Methods Thirty-two patients undergoing elective colorectal cancer resection were recruited to this randomized controlled study and assigned to two groups at random. Patient in control group was fasted before operation, while patient in study group was given oral water. Homeostasis model assessment (HOMA) indexes, activity of PTK, and mRNA and (or) protein expressions of PKB, PI3K and GluT4 were measured before and (or) immediately after surgery. Furthermore preoperative well-beings of patients were studied. Results Among well-beings, feeling of thirst, hunger and anxiety tended to be better in patients receiving carbohydrate-rich beverages compared with fasted ones (P＜0.05). Whole body insulin sensitivity decreased by 33% in the study group while 38% in the control group (P=0.007 2), and the activity of PTK, expressions of PI3K and PKB in study group were higher than those in control group (P＜0.05， P＜0.01), but no significantly difference was observed about GluT4 in both groups (Pgt;0.05）. Conclusion Preoperative consumption of carbohydrate-containing fluids is safe and effective. Provision of carbohydrate energy source prior to surgery may attenuate immediate postoperative insulin resistance. A carbohydrate-rich drink enhances insulin action at the time of onset of anaesthesia or surgery by activating three kinases named PTK, PI3K, PKB which are key enzymes in pathway of insulin signal transduction. It is likely to explain the effects on postoperative insulin resistance.
ObjectiveTo systematically evaluate the changes in placental protein expressions in gestational diabetes mellitus (GDM) and their correlations with maternal insulin resistance (IR). Methods PubMed, Cochrane Library, Scopus, Web of Science, Embase, China National Knowledge Infrastructure, VIP database, Wanfang Database and CBMdisc were searched for case-control studies published from January 2009 to November 2021, which reported the placental protein expressions in GDM and their correlations with IR. Two researchers independently reviewed the literature, extracted data and evaluated the literature quality. RevMan 5.4 software was used for meta-analysis, and descriptive analysis was performed on data that cannot be combined. ResultsA total of 19 studies were included, comprising 2 012 patients. The results of meta-analysis showed that: the expression level of retinol binding protein 4 (RBP4) [standard mean difference=2.11, 95% confidence interval (CI) (1.64, 2.58), P<0.000 01] and the positive rate of protein tyrosine phosphatase-1B (PTP1B) [relative risk (RR)=1.56, 95%CI (1.29, 1.88), P<0.000 01] were up-regulated, and the positive rate of insulin receptor substrate 1 (IRS-1) [RR=0.69, 95%CI (0.60, 0.78), P<0.000 01] was down-regulated. The protein expression levels of RBP4 (P<0.000 01) and PTP1B (P<0.000 01) were positively correlated with homeostasis model assessment of insulin resistance (HOMA-IR), while the protein expression levels of IRS-1 (P<0.000 01) and APN (P=0.002) were negatively correlated with HOMA-IR, and glucose transporter 4 (GLUT 4) was not correlated with HOMA-IR (P=0.79). Descriptive analysis found that the expression levels or positive rates of adipocytokines (leptin, resistin), oxidative stress markers (xanthione oxidase, malondialdehyde, 8-isoprostaglandin),inflammatory factors (tumor necrosis factor α, Toll-like receptor 4, Galectin-3, Galectin-2, migration inhibitory factor),fetuin-A, forkhead box transcription factor 1, forkhead box transcription factor 3a and estrogen receptor α in GDM placenta were up-regulated and all were positively correlated with HOMA-IR. The expression levels or positive rates of insulin signaling pathway proteins [phosphoinositide 3-kinase (PI3K), protein kinases B (AKT), phospho-protein kinases B (p-AKT), GLUT 4] were down-regulated, PI3K and AKT were negatively correlatedwith HOMA-IR, while p-Akt had no correlation with HOMA-IR. ConclusionsThe dysregulation of placental protein expressions may mediate maternal IR exacerbation, thus promote the occurrence and development of GDM and other pregnancy complications. The causal relationship and regulatory mechanism are still unclear, which need to be further studied.
Antimicrobial resistance is a rigorous health issue around the world. Because of the short turn-around-time and broad pathogen spectrum, culture-independent metagenomic next-generation sequencing (mNGS) is a powerful and highly efficient tool for clinical pathogen detection. The increasing question is whether mNGS is practical in the prediction of antimicrobial susceptibility. This review summarizes the current mNGS-based antimicrobial susceptibility testing technologies. The critical determinants of mNGS-based antibacterial resistance prediction have been comprehensively analyzed, including antimicrobial resistance databases, sequence alignment tools, detection tools for genomic antimicrobial resistance determinants, as well as resistance prediction models. The clinical challenges for mNGS-based antibacterial resistance prediction have also been reviewed and discussed.
【Abstract】ObjectiveTo construct an mdr1 expression vector and detect its expression in HepG2 cells in vitro. MethodsThe 4.5-kb mdr1 cDNA was obtained from the plasmid pHaMDR1 cloned into the PCIneo mammalian expression vector, which was later transferred into human hepatocarcinoma cell line HepG2 by liposome. Then the HepG2 cells resisting G418 were clustered and proliferated，and the specific fragment of mdr1 cDNA, mRNA and the Pgp in these HepG2 cells were detected by means of PCR, RT-PCR and FCM respectively. ResultsThe mdr1 expression vector was constructed successfully，and the stable multidrug resistance(MDR) hepatocarcinoma cell line （HepG2/mdr1） was developed as well. The outcome of PCR analysis showed that the specific fragment of mdr1 cDNA could be found in HepG2/mdr1 cells, but not in the nontransfection HepG2 cells. Furthermore,the content of the specific fragment of mdr1 mRNA and the expression of P-gp in HepG2/mdr1 cells were (59.7±7.9)% and (12.5±5.45)% respectively, the corresponding value in HepG2 cells were (16.9±3.2)% and (4.63±2.59)% respectively. The difference was statistically significant (P＜0.05). ConclusionIt is praticable to develop MDR hepatocarcinoma cell line by transferring mdr1 cDNA into HepG2 cells, which is useful in the research of MDR mechanism.