Objective To induce a line of Plasmodium berghei with resistance to artemisinin. Methods The major methods included blood transmission from passage to passage and progressive increase of drug pressure. Results The resistant lines were developed by different protocols: (A) The initial dosage of artemisinin was 126\^2 mg/kg which was increased by 60 mg/kg for the next passage and boosted by 126\^2 mg/kg for every other passage. As developed to passage 60 and 76, the resistant index was 18\^39∶1 and 14\^89∶1 respectively, then decreased gradually. For passage 108, the dosage was 8 862\^5 mg/kg, but the resistant index was only 10\^49∶1. (B) Using passage 66 from (A) as the source, a dosage of 4 000 mg/kg was given each week, the resistance of the passage 40 increased significantly with an index of 27\^5∶1. (C) Using passage 19 of (B) as the source, drug was administered at the dose of 2 000 mg/kg each week. The resistant index of passage 15 was 17\^41∶1. \{ Conclusion \} Line of P.berghei with medium level resistance to artemisinin was established.

Objective To analyze the molecular karyotypes of ANKA strain of Plasmodium berghei and demonstrate the size and number of chromosomes. Methods To isolate the genome DNA of P.berghei ANKA strain and analyze molecular karyotypes through CHEF-Ⅲ pulsed field gel electrophoresis (PFGE). Results The number of chromosomes was found to be 14, and their size ranged from 0\^6 Mb to 3 Mb. Chromosomes number 5 to 7 and 9 to 12 appeared co-migrated in the gel. Conclusion PFGE technique is useful for analyzing the molecular karyotypes and may be also useful for further study to locate the special gene on chromosomes and carry out the genetic characters and mechanism of drug resistance.

Objective:To observe the influence of sevoflurane pretreatment in the lung function of the infants during heart operation by cardiopulmonary bypass (CPB), and to explore its lung protection and possible mechanism.Methods:Sixty infants with ventricular septal defect were enrolled at age less than 1 year old and randomly assigned to pretreatment group and control group (n=30).After the induction of general anesthesia and tracheal intubation,the patients in pretreatment group received continuous inhalation of 1.0 MAC sevoflurane until the beginning of CPB.Inhale sevoflurane was absent in control group.The duration of ventilator support of the infants in two groups was recorded.The Pplate,CL,OI,A-aDO2 ,RI,the number of leukocytes and neutrophils segregated in lung of the patients were compared between two groups at the four time points T0 (before aorta clamping),T1 (30 min after aorta declamping),T2,and T3 (2 h and 6 h after CPB).Results:Compared with control group,the duration of ventilator support of the infants in pretreatment group was obviously shortened (P <0.05).In each group,the CL and OI were significantly decreased (P < 0.05 or P < 0.01),while the Pplate, A-aDO2 ,RI,the number of leukocyte and neutrophils segregated in lung were significantly increased (P <0.05 or P <0.01)at T1,T2,T3 time points compared with T0 time point.The CL and OI in pretreatment group were significantly increased (P <0.05 or P <0.01);the Pplate,A-aDO2,RI,the number of leukocytes and neutrophils segregated in lung in pretreatment group were significantly decreased at T1,T2,and T3 (P <0.05 or P <0.01) compared with control group.Conclusion:Sevoflurane pretreatment might play a role in decreasing the leukocyte adhesion and protecting the lung function in the infants during opening heart operation by CPB.

Objective:To study the effect of Bcl-2 short hairpin RNA (shRNA) in enhancing methotrexate (MTX)-induced apoptosis of Raji cells. Methods:Expression plasmid containing Bcl-2 shRNA was transfected into Raji cells by lipofectmine 2000 and then the transfected cells were treated with MTX. The expression levels of Bcl-2 mRNA and protein were evaluated by RT-PCR and immunofluorescence method at 48 h of transfection. MTT assay was used to analyze cell proliferation at 24, 48 and 72 h. Apoptosis was detected by Giemsa staining and flow cytomertric cell cycle analysis. Results:After transfection with Bcl-2 shRNA, the expression levels of Bcl-2 mRNA and protein in Raji cells were significantly decreased (P<0.05). Bcl-2 shRNA transfection plus MTX treatment induced marked apoptosis, decreased in cell proliferation activity, and increased in apoptotic rate. The difference was significant compared with MTX group, negative shRNA plus MTX group, Bcl-2 shRNA group, and empty plasmid plus MTX group (P<0.05). Conclusion:Bcl-2 shRNA could enhance MTX-induced apoptosis and inhibition of cell proliferation in Raji cells.

Objective To explore the differentiation of rat bone marrow mesenchymal stem cells into dopaminergic neuron.Methods The mesenchymal stem cells were isolated from bone marrow. They were induced to differentiate into dopaminergic neurons by freated with bFGF, VitC and EGF at the third generation. Dopamine-associated protein and genes in the treated cells were examined by immumofluorescence and RT-PCR. Dopamine in the supernatant and endoplasm from culture system was determined by ELISA kit. Results The results showed that tyrosine hydroxylase, dopamine transporter and nerve neucleoprotein and Nestin,Nurr-1 genes were found. And the dopamine existed in the supernatant and cytoplasm from inducing culture system. Conclusion The rat bone marrow mesenchymal stem cells have the capacity of differenting into dopaminergic nurons.

ObjectiveTo investigate the value of combined four-chamber view,left and right ventricular outflow tract view and three-vessel view of two-dimensional echocardiography (2DE) in prenatal screening for fetal congenital heart disease (CHD). MethodsFour combined views of 2DE were used to detect fetal hearts in 2419 fetuses at 21～ 25 gestational weeks.The echocardiograms were performed on all 2382 live-birth infants.Chi-square test was applied for statistical analysis.Sensitivity,specificity,positive predict value and negative predict value were calculated. Results The prevalence of fetal CHD was 11.62％ (281/2419).Among the 281 CHD fetuses,87.18％ were simple CHD (n=245) and 12.82％ were complex CHD (n=36).No difference was found in the positive rate of fetal CHD between the high-risk group and non-high-risk group [13.60％(34/250) vs 11.39％(247/2169),x2=1.069,P＜0.05].Thirty-six cases of CHD could be detected by the four combined views in prenatal screening with the sensitivity,specificity,positive and negative predictive value of 12.8％,99.8％,90.0％ and 89.7％,respectively.However,the diagnostic sensitivity of four combined views for simple CHD was 2.9％(7/245) and 80.6％(29/36) for complex CHD.The prevalence of neonatal CHD was 10.58％ (252/2382),including 241 with simple CHD and 11 complex ones. ConclusionsFour combined views of 2DE for prenatal screening is less sensitive in detecting simple CHD than complex CHD.Most of the complex CHD could be diagnosed by four combined views of 2DE before birth,but the misdiagnosis rate is high in simple CHD.The echocardiograms performed on newborns might make up for the lack.

Objective To investigate the effects and signal transduction pathway of vasonatrin peptide(VNP),a novel man-made natriuretic peptide,on hepatic fibrosis.Methods Mice were injec ted with carbon tetrachloride(CCl4)for 12 weeks,with or without VNP treatment in the last 6 weeks.HE staining and Sirius red staining were performed to evaluate the status of hepatic fibrosis.In vitro after treatment of VNP,and DNA and collagen synthesis of cultured HSC-T6 hepatic stellate cells were assessed by[3H]-thymidine and[3H]proline incorporation,respectively.The signaling pathway involved was identified by radioimmunoassay to detect the levels of intracellular cGMP,and by mimicking experiments using 8-br-cGMP(a membrane-permeable cGMP analog).Blocking experi ments were performed using HS-142-1,an antagonist of guanylyl cyclase-coupled natriuretic peptide receptor(NPR),or KT-5823,the cGMP-dependent protein kinase(PKG)inhibitor.Results VNP markedly alleviated CCl4-induced liver fibrosis in mice.In vitro,HSC-T6 cells demonstrated a dosedependent reduction of DNA and collagen synthesis in the presence of VNP.In addition,VNP significantly increased intracellular levels of cGMP.The effects of VNP were mimicked by 8-br-cGMP,but they were inhibited by HS-142-1,or KT-5823.Conclusion VNP ameliorated liver fibrosis by inhibiting collagen production from hepatic stellate cells via guanylyl cyclase-coupled NPR/cGMP/PKG signal pathway,indicating that VNP might be a new effective agent in the treatment of liver fibrosis.

Aim To investigate the role of autophagy and its mechanism in Raji cell death induced by arse-nic trioxide. Methods Transmission electron micros-copy ( SEM) and MDC fluorescence staining were used to observe autophagy. MTT colorimetry was employed to assay the cellular proliferating activity. Cell apopto-sis and cell cycle analysis were performed using FITC-Annexin-V/PI double staining and flow cytometry ( FCM) . The expressions of LC3 and the conversion of LC3-I to LC3-II were measured by western bloting. The expression of bcl-2 mRNA and p53 mRNA were detected by reverse transcription-polymerase chain re-action ( RT-PCR ) . Results Arsenic trioxide could obviously inhibit the proliferation of Raji cells, arrest the cells at G2/M phase and induce apoptosis. Mean-while, arsenic trioxide markedly inhibited the expres-sion of bcl-2 mRNA and enhanced the expression of p53 mRNA in Raji cells. Arsenic trioxide also induced autophagy synchronously which paralleled with the in-duction of apoptosis in Raji cells, and 3-MA, an auto-phagy inhibitor, was able to reverse the arsenic triox-ide-activated autophagic activity, up-regulate bcl-2, down-regulated p53 expression and suppress the lethal effect of arsenic trioxide on Raji cells to reduce their sensitivity to arsenic trioxide. In contrast, the Rapamy-cin, an autophagy inducer, possessed the completely opposite effects on Raji cells compared with 3-MA. Conclusions The apoptosis and autophagic cell death are coexistent in arsenic trioxide-triggered death of Raji lymphoma cells, and Bcl-2 and p53 may play a key regulating role in this process.

ABSTRACT:Objective To explore the protective effect of the antioxidant N‐acetylcysteine (NAC) on the retinal nerve tissue of early diabetic rats .Methods We randomly divided 60 healthy adult Sprague‐Dawley (SD) rats weighing between 180 g and 220 g into 2 groups:normal control (CON , n=20) and diabetic (DM , n=40) .By intraperitoneal injection of streptozotocin (60 mg/kg) ,the model of diabetic rats was established .The rats were considered diabetic only when they had hyperglycemia (set at ≥16 .7 mmol/L) (32) .The CON group was injected with the same amount of citric acid and sodium citrate buffer solution .After successful model establishment ,the diabetic rats were randomly divided into 1‐month diabetes group and 2‐month diabetes group ,with 16 rats in each group .The left eye of each experimental diabetic rat was set for diabetes control group (D) while the right eye was set as NAC treatment group (NAC) .At 2 weeks of diabetes ,4μL (1 .6μg/μL) of NAC was injected into the vitreous chamber of NAC group and 4μL (0 .01 mmol/L) of PBS was injected into the vitreous chamber of the other diabetic rats .The thickness changes of outer nuclear layer retina was observed by HE ,ultrastructural changes of retinal ganglion cells were observed under the transmission electron microscope ,and the number of retinal ganglion cells was detected by immunofluorescence method .Results At different time points ,retina outer nuclear layer in NAC group was thicker than in D group (P<0 .01) .However ,the NAC group and the CON group did not differ (P>0 .05) .Under the transmission electron microscope ,NAC group had more retinal ganglion cell organelles ,higher electron density of the cytoplasm ,and milder mitochondria swelling than D group .The NAC group did not differ from CON group in the ultrastructure of retinal ganglion cells . NAC group had an increased number of retinal ganglion cells at different time points compared with the D group (P<0 .01) ,but the NAC and CON groups did not differ in the number of retinal ganglion cells (P> 0 .05) .Conclusion The antioxidant N‐acetylcysteine has a protective effect on the retinal nerve tissue of early diabetic rats .

Objective To evaluate the clinical value of full-field digital mammography three-dimensional (3D) positioning system for localization and excision of nonpalpable breast lesions.Methods 106 patients with nonpalpable breast lesions and underwent preoperative localization were analyzed retrospectively.They underwent wire-localization operation guided by mammography 3D positioning system (GE Senogrphe DS).The depth of wire insertion was calculated manually and automatically.Combined with the manual measurement, systematic measurement, skin elasticity and breast parenchyma structure, the positioning wire was placed.Then, the clinical resection was performed according to the wire localization.Results The localization accuracy of mammography 3D positioning system was 100%.11 patients appearedsyncope.With the rest, psychological comfort and fluid infusion, patients recovered quickly.Conclusion Full-field digital mammography 3D positioning system can improve the accuracy of clinical resection of nonpalpable breast lesion.