Background and purpose: Multidrug resistance (MDR) of tumor cell is the main reason for clinical chemotherapy failure as well as cancer recurrence and metastasis. This study was to construct a lentiveral vector of RNA interference of MDR1 gene and observe its inhibitive role on the expression of MDR1 in A549 and A549/DDP cells. Methods: Oligos of base pairs for hairpin RNA targeting MDR1 were chemically synthesized. Via annealing and inserting them into the down-stream of H1 promoter of linearized pSUPER, we obtained the siRNA constructs for MDR1, which were afterwards transfected into A549, a human lung cancer cell line expressing high level MDR1, the impact of constructs was observed on the expression and interference efficiency of siRNA against MDR1. The effective sequence of siRNA targeting MDR1 gene was confirmed. Both sense and antisence oligo DNA of the targeting sequence was designed, synthesized and cloned into the PTM vector, containing a promoter and a green fluorescent protein (GFP). The resulting lentiviral vector containing MDR1 siRNA was named PTM-siMDR1 and then transfected into A549 and A549/DDP cells after being confirmed by PCR and sequencing. Results: Restriction digestion and DNA sequencing showed that the siRNA constructs for MDR1 were successfully produced and the expressed siRNA could effectively down-regnlate the expression of MDRI. PCR demonstrated that the lentivirus RNAi vector of MDR1 producing PTM-siMDR1 was constructed successfully. The chemosensitivity of A549/DDP cells to cisplatin were enhanced obviously after trartsfection. Conclusion: The lentivirus RNAi vector of MDR1 can significantly revise the resistance ofA549/ DDP cells with eisplatin after infection.

Objective To study the effect of dampness-eliminating and spleen-strengthening Prescription (ESP) on expression levels of adiponectin (APN) , tumor necrosis factor alpha (TNF-α) , and hepatic fat content in type 2 diabetes mellitus ( T2DM) patients complicated with non-alcoholic fatty liver disease ( NAFLD) . Methods One hundred and twenty T2DM patients complicated with NAFLD were randomized into ESP group and pioglitazone group, 60 cases in each group. Based on the fundamental treatment for decreasing glucose, ESP group and pioglitazone group were given oral use of ESP and pioglitazone respectively. Twenty-four weeks constituted one treatment course. Before and after treatment, we observed the hepatic fat content, serum concentrations of APN and TNF-α, blood glucose, blood lipid, and hepatic function with the virtual touch tissue quantification technique ( VTQ) , enzyme-linked immunosorbent assay ( ELISA) , biochemical analysator respeetively in the two groups. Results After treatment, the levels of fasting plasma glucose ( FPG) , 2-hour postprandial plasma glucose ( 2hPG) , glycosylated hemoglobin ( HbA1c) fasting insulin ( FINS) , total cholesterol ( TC) , triglyceride ( TG) , low density lipoprotein cholesterol ( LDL-C) and TNF-α, and hepatic acoustic radiation force impulse ( ARFI) scores in the two groups were significantly lower than those before treatment (P<0.05) . On the other hand, the serum levels of high density lipoprotein cholesterol (HDL-C) and APN in both groups were significantly higher than those before treatment ( P<0.05) . The difference values of FINS and NF-α before and after treatneat in ESP group were higher than those in pioglitazone group ( P<0.05) . Conclusion ESP can significantly ameliorate the metabolic disorders of glucose and lipid , protect the pancreatic function and reduce hepatic fat, which is possibly related with the increase of APN level and the de-crease TNF-αlevel.

BACKGROUND: A great quantity of cell loss in early stage following stem cell transplantation can significantly affect transplantation effect. Presently, it is confirmed that overexpression of AKT1 gene significantly inhibit cell apoptosis. OBJECTIVE: To explore whether AKT1 gene overexpression can block stem cell apoptosis under hypoxic condition following pig autologous bone marrow mesenchymal stem cell (BMSC) transplantation, and the effect of repairing damaged myocardium. DESIGN, TIME AND SETTING: The randomized controlled animal study was performed at the Soochow University from August 2005 to February 2007.MATERIALS: A total of 24 healthy male Meishan pigs were supplied by the Animal Experimental Center of Soochow University. METHODS: The CDS (regulation domin of AKT1) AKT1-cDNA fragment was amplified. Lentivector Packaging Kit was used to transfect BMSCs after synthesized with pCDH1-AKT1 shuttling plasmid. Following BrdU labeling, models of myocardial infarction were constructed by occluding the distal left anterior descending coronary artery in pigs with gelatin sponge. 4 weeks later, pigs were randomly divided into four groups: the model control group, the DMEM group, the BMSCs group, and the AKT-transfected group. In model control group, there was no other injection after occluding the left anterior descending coronary artery. In the DMEM group, 5 mL DMEM was injected into the coronary artery. 5 mL BMSCs (1×10~7 cells) were infused into the coronary artery in the BMSCs group. 5 mL BMSCs transfected with the AKT1 gene were injected in the AKT-transfected group MAIN OUTCOME MEASURES: Western blot analysis and real time RT-PCR were used to test the plasmid. The cardiac function was evaluated by magnetic resonance image. Histological characteristics of the myocardium were observed using immunohistochemistry. Serum vascular endothelial growth factor and transforming growth factor β1 levels were determined by ELISA. RESULTS: AKT1-cDNA was cloned into pCDH1-MCS1-EF1-copGFP and the sequence was confirmed in comparison with the published one. AKT mRNA expression could be detected distinctly 24 and 48 hours after transfecting cells. The expression of AKT1 intensity in MSCs remained strong 2 weeks later with detected by real time RT-PCR and Western blot analysis. AKT1-mRNA transcriptional levels were 120 times of primary cells. Before the cell implantation, the left ventricular end-diastolic dimension increased and the stroke volume decreased in the myocardial infarction hearts. The cardiac function was significantly improved after cell implantation, and the implanted MSCs prevented the infarct region from thinning and expanding, improved contraction and increased perfusion in all groups relative to the control hearts. The left ventricular chamber size was smaller in the hearts with being transplanted cells than that in the control hearts. Moreover, the improvement was even markedly greater in AKT-transfected group (P < 0.05). Hematoxylin-eosin staining results showed that fibering was significant in the model control group and DMEM group. Island-like myocardium was observed in the infarct zone of the BMSCs group and AKT-transfected group, and plenty of small vessels-shape structure was detected in the AKT-transfected group. Immunohistochemistry demonstrated that Von Willebrand Factor (vWF) and Cx-43 expression was determined in the myocardium in the BMSCs group and AKT-transfected group, and the proportion of BrdU and Cx-43-positive cells to BrdU-positive cells was significantly greater in the AKT-transfected group compared with the BMSCs group 4 weeks following transplantation (P < 0.05). Following cell transplantation, vascular endothelial growth factor levels were gradually increased, peaked at 1 week, gradually decreased, and reached a normal level at 4 weeks. Transforming growth factor p1 levels were gradually reduced, and significantly less than the model control group, DMEM group 4 weeks later (P < 0.05), and significantly lower than that pretransplantation (P < 0.05).CONCLUSION: Using lentiviral vector to construct with AKT1 gene could stably make BMSCs overexpress AKT1. The BMSCs engraftment in host myocardium might improve the left ventricle function by attenuating the contractile dysfunction and pathologic thinning in this model of left ventricular wall infarction. AKT1 overexpression can significantly improve cardiac function following infarction.

Background and Objectives: Circulating endothelial progenitor cells (EPCs) participate in vascular repair and predict cardiovascular outcomes. The aim of this study was to investigate the correlation between EPCs and abdominal aortic aneurysms (AAAs). Methods: and Results: Patients (age 67±9.41 years) suffering from AAAs (aortic diameters 58.09±11.24 mm) were prospectively enrolled in this study. All patients received endovascular aneurysm repair (EVAR). Blood samples were taken preoperatively and 14 days after surgery from patients with aortic aneurysms. Samples were also obtained from age-matched control subjects. Circulating EPCs were defined as those cells that were double positive for CD34 and CD309. Rat models of AAA formation were generated by the peri-adventitial elastase application of either saline solution (control; n=10), or porcine pancreatic elastase (PPE; n=14). The aortas were analyzed using an ultrasonic video system and immunohistochemistry. The levels of CD34＋/CD309＋ cells in the peripheral blood mononuclear cell populations were measured by flow cytometry. The baseline numbers of circulating EPCs (CD34＋/CD309＋) in the peripheral blood were significantly smaller in AAA patients compared with control subjects. The number of EPCs doubled by the 14th day after EVAR. A total of 78.57% of rats in the PPE group (11/14) formed AAAs (dilation ratio ＞150%). The numbers of EPCs from defined AAA rats were significantly decreased compared with the control group. Conclusions EPC levels may be useful for monitoring abdominal aorta aneurysms and rise after EVAR in patients with aortic aneurysms, and might contribute to the rapid endothelialization of vessels.

Islet β cell dedifferentiation is one of the important reasons leading to insulin secretion defect or insulin resistance in patients with type 2 diabetes mellitus(T2DM).HIF-1α/PFKFB3 signaling pathway is a newly discovered biological pathway related to T2DM,which is involved in the induction of islet β cells dedifferentiation by anaerobic glycolysis under high glucose environment.This article reviews the research progress of the role of HIF-1α/PFKFB3 signaling pathway in glycolysis induced islet β cell dedifferentiation.

Objective To investigate the effects and complications of mitral valve membrane replacement surgery with preservation of mitral valve subvalvular structure on cardiac and valve function.Methods A total of 84 patients receiving mitral valve membrane replacement surgery with preserved mitral valve subvalvular structure in the First Affiliated Hospital of Soochow University from August 2019 to July 2022 were selected as the observa-tion group,and 68 patients receiving mitral valve membrane replacement surgery without preservingmitral valve subvalvular structure were selected as the control group.The surgical indicators,comorbidities,preoperative and postoperative cardiac function,and mitral valve hemodynamic parameters were compared between the two groups.Results There was no statistically significant difference between the observation group and the control group in terms of surgical history,extracorporeal circulation time,aortic occlusion time,postoperative mechanical ventilation time,ICU retention time,and postoperative hospitalization time(P>0.05).At 1,3,and 6 months after surgery,the left ventricular end systolic diameter(LVESD)and left ventricular end diastolic diameter(LVEDD)in the observation group were significantly lower than those in the control group(P<0.05),while the left ventricular short axis shortening rate(LVFS)was significantly higher than that in the control group(P<0.05).There was no statistically significant difference in left ventricular ejection fraction(LVEF)between the observation group and the control group at 1,3,and 6 months after surgery(P>0.05).There was no statistically significant difference(P>0.05)in the peak mitral valve velocity(Vmax),maximum pressure gradient difference(PGmax),and mean pressure gradi-ent difference(PGmean)between the observation group and the control group at 1,3,and 6 months after surgery.There was no statistically significant difference in creatine kinase isoenzyme(CK-MB)and N-terminal precursor brain natriuretic peptide(NT-proBNP)between the observation group and the control group at 1,3,and 6 months after surgery(P>0.05).There was no statistically significant difference in the incidence of postoperative complica-tions between the observation group and the control group(P>0.05).Conclusion The preservation of the mitral valve subvalvular structure and mitral membrane replacement surgery improved patient cardiac function,while there was no significant difference in mitral valve orifice blood flow parameters and complications compared with surgery without preservation of the mitral valve subvalvular structure.

Objective:To evaluate the efficacy of cerebral-placental-uterine ratio(CPUR)in predicting late-on-set fetal growth restriction(FGR).Methods:From May 2020 to May 2021,1255 women with singleton pregnancy who underwent prenatal examinations at the University of Hong Kong Shenzhen Hospital were selected for fetal growth and Doppler measurements at 35-37 +6 weeks of gestation.Pregnant women with birth weight of newbo-rns＜the 10th percentile were the FGR group.The pulsatility index(PI)of uterine artery(UtA),umbilical artery(UA)and fetal middle cerebral artery(MCA)were analyzed separately and in combination.ROC curve was used to analyze the cerebral-placental-uterine ratio(CPUR),cerebral-placental ratio(CPR),cerebral-uterine ratio(C-UtA)for predicting late-onset FGR;and to evaluate the sensitivity,positive and negative predictive value and of CPUR in the prediction of late-onset FGR.Results:The area under the curve(AUC)of CPUR,CPR,C-UtA and mean UtA-PI for FGR grope were 0.88,0.86,0.84 and 0.72.Under certain cut-off values and 87% specificity,the specificity of CPUR,CPR,C-UtA and mean UtA-Pifor predicting FGR group was 43.2%,46.6%,39.8% and 23.9%,respectively.The positive predictive values of CPUR,CPR,C-UtA and mean UtA-PI,UA-PI for predicting FGR group were 90.5%,71.9%,83.3%,63.6%and 5.2%,respectively.Conclusions:CPUR is more effective in predicting late onset FGR than CPR,C-UtA and mean UtA-PI.It can effectively increase the detection rate of fetal growth restrictionand reduce the FGR risk.

Lumbar spondylolysis is one of the common diseases of low back pain caused by spinal surgery. Its treatment options vary depending on different conditions, from early conservative ones to late surgical ones. There are still disputes over various conservative treatments, choice of surgical methods and the biomechanics of different internal fixation techniques to repair spondylolysis. Therefore, this review summarizes the clinical outcomes of previous clinical treatments of lumbar spondylolysis and the biomechanical characteristics of various techniques to find the mechanical and evidence-based clinical data that may facilitate the treatment of lumbar spondylolysis.

Objective·To develope an auditory brainstem implant(ABI)vocoder based on cochlear implant(CI)vocoder characteristics and ABI electrode array topology,and to verify its reliability.Methods·An"n-of-m"coding strategy CI/ABI vocoder was constructed based on MATLAB.Within each frame,only the envelopes of the n channels with the highest energy were selected.The interaction coefficient(IC)(range:1?3),channel numbers(range:5?22),and electrode array topology(CI/ABI)were adjustable parameters,allowing for the synthesis of simulated speech.Psychoacoustic evaluation was employed,recruiting normal hearing subjects to perform closed-set simulated phoneme perception.The phoneme recognition accuracy(20 vowel questions/condition,11 consonant questions/condition)was compared with the corresponding conditions of CI and ABI from reference literature to determine the IC value of the vocoder and verify its reliability.Results·The vocoder successfully synthesized all test stimuli.In the closed-set CI-simulated speech recognition,the simulated vowel and consonant recognition accuracy for IC2 and IC3 conditions showed no significant difference compared to the accuracy reported in the CI reference literature(P＞0.05).The difference in vowel and consonant accuracy between IC2 and the literature was smaller than that between IC3 and the literature(vowel|d|=1.6%vs.20%,consonant|d|=8.4%vs.9.9%),thus determining the optimal interaction coefficient of this model as 2.Subsequently,when modifying the electrode array topology to ABI,it was found that the simulated phoneme recognition accuracy for a 16-channel ABI was significantly lower than that for the 16-channel CI group,consistent with the reported literature.The simulated vowel and consonant accuracy within the 5?8 channel range for ABI showed no significant difference(P＞0.05),also aligning with the trend reported in the literature.Conclusion·A CI/ABI vocoder based on"n-of-m"coding strategy is established and the optimal IC is determined.The established ABI encoder has been evaluated for high reliability through psychoacoustic experiments.It provides suitable technical means for validating ABI-specific coding strategies.