Biodegradable nano/microparticles of poly(D, L-lactide-co-glycolide) (PLGA) is a novel non-viral gene vector, which has many advantages, such as safety, non-immunogenicity, easy of large-scale preparation and well load-capability. Therefore, more and more attentions and researches have been paid on its application. Especially, PLGA has shown enormous potential application value and space in the field of plasmid DNA (pDNA) delivery system. On the basis of the current situation of PLGA nano/microparticles for pDNA delivery, this paper focused on summarizing the current preparation approaches and surface modified methods of PLGA particle, furthermore showing its application in gene therapy and genetic vaccine delivery. These showed that PLGA nano/microparticles have extensive prospect in the development of controlled gene delivery system.

Objective:To investigate the efficacy and safety of ticagrelor and clopidogrel in patients with coronary atherosclerotic heart disease (CHD) and hyperhomocysteinemia (Hhcy).Methods:A total of 101 patients with CHD complicated with HHcy who had successfully undergone percutaneous coronary intervention (PCI) were enrolled. They were divided into ticagrelor group ( n=49) and clopidogrel group ( n=52) according to the different antiplatelet drugs used. The clinical data of the two groups were collected, and the incidence of major cardiovascular and cerebrovascular adverse events (MACCE) and bleeding events in one year were compared between the two groups. Results:There was no statistical difference in baseline datas and PCI datas between the clopidogrel and ticagrelor groups ( P>0.05). Compared with clopidogrel group, ticagrelor can reduce the total MACCE (8.16% vs 32.69%, P<0.05) and the incidence of unstable angina pectoris events (0 vs 13.46%, P<0.05) in patients with hyperhomocysteinemia PCI 1 year after operation. The incidences of ischemic stroke, unstable angina pectoris, recurrent myocardial infarction, and cardiogenic death were compared separately between the two groups, and the difference was not statistically significant ( P>0.05). The incidence of major bleeding events, minor bleeding events, and minimal bleeding events were similar between the two groups, and the difference was not statistically significant (4.08% vs 0; 4.08% vs 1.92%; 20.41% vs 9.62%; P>0.05). Conclusions:In patients with CHD and Hhcy, ticagrelor can play a better antithrombotic effect, reduce the incidence of ischemic events, and has good security, which is more worthy of clinical recommendation.

Objective To evaluate the diagnostic value of magnetic resonance tomographic angiography(MRTA) with 3.0T scanner for neurovascular compression in patients with trigeminal neuralgia and hemifacial spasm.Methods MRTA using three-dimensional time-of-flight(TOF) sequence was performed in 52 cases with trigeminal neuralgia and 9 cases with hemifacial spasm.MR oblique sagittal and coronal images were created to display the relationship between trigeminal and facial nerves and surrounding vessels,and compared with that of operation MRA showed that.Results In 52 cases with trigeminal neuralgia,the trigeminal nerves were compressed by vessels or contacted with vessels in 46 cases at MRTA,and in 9 cases with hemifacial spasm,all trigeminal nerves showed having vascular compression or in contact with vessels.The accuracy,sensitivity and specificity of MRA in diagnosing trigeminal neuralgia and hemifacial spasm caused by vascular compression were 90.2%,96.4% and 80%,respectively,which compared with that of operation.Conclusion MRTA is sensitive to neurovascular compression,which plays an important role in diagnosing trigeminal neuralgia and hemifacial spasm.

Objective:To investigate the role of p21 gene in the radiation-induced heart disease (RIHD) and to evaluate the effect on p21 gene knockout on RIHD phenotype in mouse models.Methods:p21 -/-mice were utilized in the experimental group, and p21 + /-mice were allocated in the control group. RIHD mouse models were established by exposure to 10 Gy whole heart irradiation by using a small animal radiation research platform. The heart samples were collected at 6 weeks after irradiation, the gross specimens were measured and subject to HE staining. The wall thickness and left ventricular ejection fraction of the mice were detected by the Vevo2100 ultrasound imaging system. The hypoxia in cardiac tissues was detected by the hypoxia probe method. The apoptosis of cardiac cells was determined by Tunel method. Results:Compared with the p21 + /-mice, the survival of p21 -/-mice was significantly shortened ( P=0.004), the interventricular septum was significantly thinned during the diastolic and systolic phases ( P=0.049, P=0.006), the left ventricular posterior wall was remarkably thickened ( P<0.001) and the left ventricular ejection fraction was significantly decreased ( P=0.004). The gross heart tissue was enlarged in the p21 -/-mice. HE staining showed the aggregation of inflammatory cells in cardiac tissues and disordered arrangement of myocardial cells. Significant hypoxia and apoptosis could be observed in the p21 -/-mouse heart tissues. Conclusions:p21 -/-mice are prone to more severe RIHD after irradiation, manifested with shortened cardiac survival, weakened cardiac function, abnormal cardiac structure, hypoxia and apoptosis of cardiac tissues. p21 plays an important role in the repair after cardiac irradiation.

BackgroundWhether the peeling of the inner limiting membrane (ILMP) increase the closure rate of idiopathic macular hole is still in controversy.Some ophthalmologist recommend vitrectomy combined with inner limiting membrane peeling for the treatment of idiopathic macular hole.However,the removal of ILMP is difficult because of its similar appearance to adjacent tissues.Objective This study was to investigate the efficacy of triamcinolone acetonide(TA) and indocyanine green(ICG) double staining-assisted vitrectomy combined with ILM peeling during the surgery.Methods A consecutive case- observational study was designed.The standardized vitrectomy was performed in 25 eye of 23 cases with IMH.During the vitrectomy,TA and ICG were injected into posterior pole vitreous to visualize and assist the ILM peeling.The dying effectiveness was observed,and the closure rate of macular hole,visual acuity,intraocular pressure and complications were evaluated after surgery.Written informed consent was obtained from each patient prior to operation.Results Posterior vitreous cortex and ILM were visible and the residual vitreous and cortex were removed clearly after dying of TA and ICG in all the 25 eyes.During the following-up duration of 3-8 months,the completely anatomical reattachment of the macular area was in 22 eyes ( 88.0％ ) and partially reattachment in 3 eyes( 12.0％ ).The best corrected vision was 0.07-0.60 in all of the operated eyes 2 months after surgery.Conclusions TA and ICG- assisted vitrectomy combined with ILM peeling appears to be a safe and effective method for IMH repair.

Objective To observe the pathological changes of bone hydatid cyst of meriones meridianus after radiation therapy,and to investigate the clinical effect of radiotherapy on bone hydatid disease.Methods Ascus was dissected sterilely from sheep liver that naturally infected with Echinococcus granulomas,sheared and sac skin removed.Then it was washed and precipitated with 0.9％ sterile saline for 3 times,and scolex was HE stained and counted,from which a 20 ml suspension was made containing 12 × 106/L of scolex.Health meriones meridianus (referred to as gerbil) 140,male and female were in each half,aged 2 to 3 months,body weight(38 ± 6)g,were involved in the study.Gerbil was injected a 0.2 ml suspension containing Echinococcus granulomas scolex into hind tibial periosteum,and X-ray was taken 12 months after the injection.According to the bone destruction in the vaccination site,gerbil hindleg tibia with clear jagged bone destruction was treated as inclusion criteria,and 72 animal were selected as gerbil bone hydatid disease animal models,male and female were in each half.A tatal of 72 gerbils were randomly divided into 4 groups:control group,40 beequerel(Gy) group,50 Gy group and 60 Gy group,18 rats in each group,male and female in each half.The model animals were treated with radiotherapy for 5 times,with 2 d interval,and radiation dose was 300 cGy/min.Each group of gerbils was sacrificed after radiotherapy,bone Echinococcus granulomas cysts was taken out sterilely,and observed by light and electron microscope.Intracapsular cyst fluid was extracted,washed and precipitated with 0.9％ sterile saline repeatedly,and and the pellet was HE stained for observation of scolex morphology and activity by light microscope.Results The morphology and activity ofEchinococcus granulomas in cystic fluid in control group were normal; the morphology and activity of Echinococcus granulomas were still normal in the 40 Gy group,and Echinococcus granulomas was not stained red; but those were abnormal,deformation and atrophy and stained red in the 50 Gy group; and were stained red,deformed,fractured and were wrapped by unknown in the 60 Gy group.By light microscope,the germinal layer,cuticle layer,brood capsule and histological structure of protoscolex were basically normal in irradiated region in the control group.The pathological changes of hydatid cyst in the 40 Gy group were mainly degeneration,structure of hydatid cyst was abnormal,stratum corneum was extensive edema,germinal layer became thinner and the fertile cyst was rare.The main pathological change of hydatid cyst in the 50 Gy group was that corneous layer was widely fractured,and the germinal layer was edema,buckling folds,cells decreased,rare seen brood capsule and scolex; the main pathological changes of hydatid cyst were mainly necrosis in the 60 Gy group,cuticle was extensive fault,stratum corneum and germinal layer was separated,germinal layer was atrophy and disorder,no brood capsule and scolex.By electron microscope,cuticle structure of Echinococcus granulomas cyst was clear,microvillus arranged neatly,morphology and structure of the cell and organelle in cytoplasm were normal in the control group.There were many inflammatory cells infiltrating germinal layer of Echinococcus granulomas cyst,microfilament and contents in microfilament were reduced in the 40 Gy group.Microvillus of Echinococcus granulomas disappeared,nuclear membrane was unclear,endoplasmic and mitochon eclasis,lymphocyte nuclear chromatin was clumping and edge set and in circular permutation in the 50 Gy group.Microvillus disappeared,perinuclear membrane indistinct and ruptured,parts of nucleoli were fragmented and marinated,endoplasmic reticulum was extensive expansion,mitochondria was pyknosis and obvious vacuolization,lymphocyte nuclear chromatin clumping and edge set,lysosomes and macrophage emerge in the 60 Gy group.Conclusions Radiotherapy can destroy the morphology and structure of bone hydatid cyst,radioactivity at 50 Gy has a lethal effect on hydatid cyst.Radiation treatment of bone hydatid disease has a good clinical effect.

Purpose To investigate the histopathological features of cystic lung diseases ( CLD) , and to discuss the timing of clinical interventions. Methods HE and immunohistochemical staining were performed and reviewed in 125 cases of CLD. Results 125 ca-ses of CLD aged from birth to 11 years and 6 month, with an average age of 23. 0 months, median age 15 months, of which 60 cases were less than 1 year (48. 0%). 75 cases were male and 50 cases female, with male to female ratio of 1. 5 ∶ 1. Grossly, 50 cases showed single or multiple cysts with the size 0. 5 ~8. 0 cm in diameter, which did not communicate with bronchial cavity. 18 cases showed honeycomb cysts with the diameter of 0. 1~2. 0 cm. 26 cases were solid lesions without visible cysts. 21 cases were observed lung abscess with thick and rough wall and pus inside. 7 cases of emphysema showed microcysts with crepitation. 2 cases were identi-fied cystic and solid masses, with fish-fresh like cut surface. Histopathologically, 94 cases (75. 2%) were related to congenital bron-chopulmonary dysplasia in 125 cases of CLD, in which there were 59 patients (47. 2%) of congenial pulmonary airway malformation (CPAM), including 29 cases of type 1 (49. 2%), 18 cases of type 2 (30. 5%), and 12 cases of type 4 (20. 3%), there were 26 ca-ses (20. 8%) of pulmonary sequestration, including 15 cases of intralobar type (57. 7%) and 11 of extralobar cases (42. 3%), 5 ca-ses were complicated with CPAM type 2, 8 cases were bronchial cyst (6. 4%) and 1 case of enteric cyst (0. 8%). Acquired lesions were detected in 31 cases (24. 8%), including 21 cases of infected lung abscess, 1 case of fungal abscess. 7 cases of emphysema, and 3 cases of pleuralpulmonary blastoma (typeⅠ1 case and typeⅡ2 cases). Conclusion Pediatric CLD is characterized as com-plexed categories. The prognosis depends on correct pathological diagnosis, combined with imaging evaluation and appropriate timing of surgery.

Background and purpose: Resistance of cancer cells to chemotherapy is a major clinical obstacle to successful treatment and leads to poor prognosis for the patients. MicroRNA (miRNA) plays a vital role in tumor cells response to chemotherapeutic agents. This study plans to investigate the expressions of miRNA27a and miRNA451 in ovarian cancer and breast cancer cells and its correlation with drug resistance. Methods:A2780/Taxol cells were established using stepwise selection;Stem-loop quantitative real-time PCR (stem-loop RT-PCR) was used to detect expression of miRNA27a and miRNA451 in ovarian cancer and breast cancer cells. The A2780 and A2780/Taxol cells were transfected with the mimics or inhibitors of miRNA27a or negative control (NC) RNA and the mimics of miRNA451 or NC were transfected into MCF-7/ADM cells by LipofectamineTM 2000. The expression levels of MDR1 mRNA and P-glycoprotein (P-gp) were examined using RT-PCR and Western blot respectively. MTT method was used to analyze drug sensitivity. Results:The expression of miRNA27a was an average of (2.2±0.30) times higher in A2780/Taxol cells than in A2780 cells, with a significant difference between the two groups (P<0.05). The expression of miRNA451 was lower by 84%in MCF-7/ADM cells than in MCF-7 cells, with a signiifcant difference between the two groups (P<0.05). A2780/Taxol cells transfection with inhibitors of miRNA27a showed that the levels of MDR1 mRNA was decreased by (39±0.14)%, P-gp level [(26±5.3)%] decreased compared with the NC group [(43±6.7)%], the IC50 (0.53μmol/L) was less than the NC group (6.8μmol/L), and there was a signiifcant difference between two groups (P<0.05). Transfection of A2780 cells with mimics of miRNA27a led to increase MDR1 mRNA expression by (121±0.11)%and decrease the sensitivity to paclitaxel (IC50:0.2μmol/L vs 0.06μmol/L). There was a signiifcant difference between two groups (P<0.05). Transfection of MCF-7/ADM cells with mimics of miRNA451 showed that expression of MDR1 mRNA was decreased by (65±12)%, P-gp [(31±19)%] was less than the NC group [(83±12)%], the sensitivity of cells to adriamycin enhanced and the IC50 of adriamycin (4.61μmol/L) was less than the NC group (26μmol/L), and there was a signiifcant difference between two groups (P<0.05). Conclusion:The expressions of miRNA27a and miRNA451 are deregulated in A2780/Taxol and MCF-7/ADM cells respectively, which may play vital roles in drug resistance by regulating MDR1/P-gp expression directly or indirectly.

Objective To determine the value of helical computed tomography (HCT) and color doppler flowing imaging (CDPI) in evaluating the resectability of pancreatic cancer. Methods The clinical data of 114 patients with pancreatic cancer who had been admitted to the Affiliated Hospital of North Sichuan Medical College from January 1995 to December 2002 were retrospectively analyzed. The values of HCT and CDPI in assessing the resectability of pancreatic cancer were determined according to the results of operation and pathological examina-tion. All the data were analyzed by chi-square test and Fisher exact probability. Results Of all patients, 109 were examined by HCT, 97 by CDPI and 96 by HCT+CDPI. For patients examined by HCT, the resection rates of pancreatic head cancer, pancreatic body and tail cancer and total pancreatic cancer were 45.3% (39/86), 26.3% (5/19) and 0 (0/9), respectively. The resection rate of pancreatic head cancer was higher than that of pancreatic body and tail cancer (χ2=8.965, P<0.05). With the increase of tumor size, the invasion rate and metastasis rate were increased and the resection rate was decreased (z=6.15, 5.35, 7.18, P<0.01). The sensitivity rate and specificity rate were 77.8% and 82.2% of HCT, 73.3% and 80.6% of CDPI, 90.6% and 92.4% of HCT+CDPI in assessing the resectability of pancreatic cancer. The values of Kappa identity test of HCT, CDPI and HCT+CDPI were 0.58, 0.52 and 0.82, respectively. Conclusions Combined application of HCT and CDPI can further improve the accuracy in assessing the resectability of pancreatic cancer.

Objective To investigate the clinical value of VVI assessment normal fetal segmental myocardial performance and to establish a nomogram of normal fetus.Methods Digital dynamic fourchamber imaging of 151 healthy fetus(divided 5 groups according to gestation)were collected,then the longitudinal velocity,strain and strain rate of interventricular septal and left lateral wall were measured in systolic and diastolic period respectively.Results Normal systolic and diastolic values for tissue velocitv.strain,and strain rate were established.Tissue velocity was age dependent,whereas strain and strain rate were stable throughout gestation(P＞0.05).Tissue velocity was gradually decreased from the base segment to the apical segment(P＜0.01),whereas strain and strain rate were stable among all segments in every group(P＞0.05).Conclusions Fetal myocardial velocity,strain,and strain rate measuraments are easy to obtain and reproducible,VVI is a novel noninvasive tool to assess quantitatively and objectivelv regional systolic and diastolic function in fetal heart,it is providing another useful modality for evaluating cardiac function.