Traditional recombination technology of bacteria chromosome and its limitation were introduced. The definition of Red recombination technology is put forward: a method of homologous recombination between foreign linear DNA and the target gene in chromosomes mediated by ? phage Red system. The linear DNA referred here is general PCR product or oligonucleotide, which has a 36~50bp homologous sequence with the target gene in chromosome at both flanking. Red recombination technology leaves out the in vitro DNA restriction enzyme digestion and link process, which makes the knockout and alternation of target gene in bacteria chromosome relatively easier, and becomes an effective method to exploring genes and constructing new strains gradually. The gene inactivation and alternation method aiming at bacteria chromosome applied to Red recombination system was summarized by the structure element, action mechanism, and strategy of recombination, advantage and developing prospect. The Red system includes three genes: bet (aka?), exo and gam (aka ?). Exo is a 5′→3′ exonuclease, which degrades the 5′ ends of linear DNA molecules. Bet is a single-stranded DNA binding protein that binds to the single stranded 3′ ends generated by Exo and promotes annealing to complementary DNA. Gam binds to the host RecBCD complex and inhibits its exonuclease activity. Red recombination system may be constructed in such plasmids as pKD20 and pKD46 or in chromosome of bacteria. Most bacteria are not readily transformable with linear DNA because of the presence of intracellular exonucleases that degrade linear DNA. But when bacteria cells are transformed with pKD20 or pKD46 plasmid, or integrated with a detective ? prophage, Red recombination enzymes may be expressed in host cells, which make linear DNA with 36~50bp extensions that are homologous to both flanking of target genes transform E.coli readily and knock-out or alternate target gene. The Red recombination method is not only useful in chromosomal gene inactivation in E.coli, but also in other bacteria or virus, such as Salmonella, Shigella flexneri and virus HaSNPV. With the proceeding research, Red system will be applied for more and more purposes, and contribute a lot for gene improvement and gene function investigation in the coming Postgenome Era.

Objective To investigate the effect of morphine combined with cisplatin on inva-sionon and migration of human lung adenocarcinoma cell A549.Methods Human lung adenocarcino-ma A549 cells were inoculated on cultured for 24 h,then were randomly divided into 5 groups:control group (group CON),cisplatin group (group CIS),morphine 0.3 μg/ml+ cisplatin group (group MT1),morphine 3 μg/ml+ cisplatin group (group MT2),morphine 30 μg/ml+ cisplatin group (group MT3).Cisplatin concentration was 4μg/ml.Each group was medicated immediately after 48 h incubation,invasion detection cells by Transwell assay,cell scratch assay cell migration ability, Western-blot detection of matrix metalloproteinase-2 (MMP-2),the expression of MMP-9,Ezrin protein and Fascin protein.Results Compared with group CON,group CIS and morphine combined with cisplatin group reduced tumor cell invasion and migration ability,group MT3 and CIS down-reg-ulated MMP-2,MMP-9,Ezrin and Fascin expression (P<0.05).Compared with group CIS,com-bined with cisplatin group enhanced tumor cell invasion and migration ability group MT3,up-regula-ted MMP-2,MMP-9,Ezrin and Fascin expression (P<0.05).Conclusion Morphine may dose de-pendently reduce cisplatin on invasion and migration of human lung adenocarcinoma cell line A549, and up-regulation of MMP-2,MMP-9,Ezrin,Fascin expression is one of its possible mechanisms.

Objective: To investigate the inhibitory effect of adenovirus-mediated VEGF-siRNA on transplanted osteo- sarcoma in nude mice.Methods: VEGF-siRNA gene was cloned into the genome of replication-deficient adenovirus to construct Ad-VEGF-siRNA;the latter was then used to infect osteosarcoma MG63 cell line in vitro;and the expression of VEGF gene was detected by RT-PCR.Osteosarcoma transplantation model was established in nude mice;VEGF expression in tumor tissue was analyzed and the inhibitory effect on tumor growth and lung metastasis were also observed.Results: The recombinant adenovirus vector Ad-VEGF-siRNA was successfully constructed.In vivo and in vitro experiment both showed that Ad-VEGF-siRNA significantly downregulated VEGF expression in MG63 cells and transplanted tumor tissue. It was found that Ad-VEGF-siRNA significantly inhibited transplanted osteosarcoma growth(P

Objective To develop a medical equipment management information system in CAPF so as to improve current medical equipment management and maintenance level.Methods Based on a thorough research for current medical equipment management model in CAPF,the platform of NET was utilized to develop the software.The connection,combination and operation among all medical equipment management and maintenance work were realized by hardware construction at last.Results The management information system not only met the requirement in management of medical equipment,but also supplied a data basis to directors.Conclusion The management information system provides a powerful tool for the scientific and standard management of medical equipment in CAPF.

This study aimed to evaluate the influence of quartz fiber post placement on the fracture resistance of endodontically treated premolars with different dental defects under dynamic loading. Fifty extracted single-rooted mandibular premolars were randomized into five groups. Each group was prepared according to numbers of residual walls ranged from 0 to 4. Then each group was divided into two subgroups with one restored with quartz fiber posts and the other without posts. In no-post groups, gutta percha point 2 mm below cemento-enamel junction was removed. Composite resin was adapted to the well and used to shape the core directly. Each tooth was restored with a complete metal crown. Dynamic loading was carried out in a masticatory simulator with a nominal load of 50 N at 2 Hz for 300 000 loading cycles. Then a quasi-statically load was applied in a universal testing machine 30° to the long axis with a crosshead speed of 1 mm⋅min(-1) until fracture. Data were analyzed with one-way analysis of variance and pairwise comparison (P<0.05). No specimens failed during dynamic loading. The fracture resistance enhanced with the increase of numbers of coronal walls and the differences were significant (P<0.05). Placement of fiber posts had a significant effect when fewer than two walls remained (P<0.05), but it had no significant influence in groups with two, three or four walls (P>0.05). Fiber post did not change failure mode, and the fracture pattern was mainly favorable. More dentin walls need to be retained in clinic. When no less than two walls remained, a fiber post is not always necessary.
Analysis of Variance ; Bicuspid ; Composite Resins ; Dental Restoration Failure ; Dental Stress Analysis ; Dentin ; physiology ; Humans ; Post and Core Technique ; Quartz ; Tooth Fractures ; prevention & control ; Tooth, Nonvital

Eating disorder is a kind of complex multifactorial disease. Although the etiology of the disease is still not fully expounded, it is certain that its etiology is closely related to biological, psychological and sociocultural factors. It is helpful to make early predictions and interventions for patients with eating disorders by learning through the studies of risk factors for eating disorder, which is also meaningful to provide more guidance and evidence for clinical work. Guided by recent studies, this review summarizes recent findings and clarifies the latest identified risk factors for eating disorders in the main areas of biology, psychology, and sociocultural environment.

ObjectiveTo study the effect of enriched rehabilitative training on the functional recovery and neuronal dentritic growth following cerebral ischemia/reperfusion.Methods32 male Wistar rats,weighting 180～200 g,were randomly divided into a ischemic group(n=16) and a sham-operation group(n=16) after beforehand trainings.Rats were subjected to 2 h of right middle cerebral artery occlusion before reperfusion.After surgery,the ischemic group were randomly divided into a ischemia + enrichment(IE) group and a ischemia + standard housing(IS) group;the sham-operation group were randomly divided into a sham + enrichment(SE) group and a sham + standard housing(SS) group.After 24 h reperfusion,IE and SE groups were housed in enriched cages,and given enriched rehabilitative training according to the scheme.At the same time,IS and SS groups were housed in standard cages without any training.The functions of 4 groups were evaluated at 24 h,1 week,2 weeks,3 weeks and 4 week after operation.Dentritic growth of layer V pyramidal cells of the undamaged forelimb motor cortex was examined using Golgi-Cox procedure.ResultsIE group showed better function than IS group in all behavioral test.There was no significant difference in limb-placement test at 3 weeks(P>0.05) and in footfault test at 4 weeks(P>0.05) after operation between IE and SE group.The mean of basilar dentrite branching points in IE group was significantly greater than that of other groups(P<0.01).ConclusionEnriched rehabilitative training can promote functional recovery and enhance neural plasticity after cerebral ischemia/ reperfusion in rats.

Objective To perform prenatal diagosis for two fetuses carrying partial deletion of Y chromosome.Methods Routine G-and C-banding were carried out to analyze the chromosomal karyotypes of the fetuses and their fathers.Fetal DNA was also subjected to low-coverage massively parallel copy number variation sequencing (CNV-seq),fluorescence in situ hybridization (FISH),SRY gene and AZF factor testing.Results Both fetuses showed a 46,XN,del(Y)(q11.2) karyotype at 320-400 band level by the analysis of amniotic fluid chromosomes.FISH with Y chromosome centromere probe indicated that in both cases the number of Y chromosome was normal.Both fathers had an apparently normal karyotype at 320-400 band level.For fetus 1,CNV-seq test revealed a 12.88 Mb deletion at Yq11.221-q12,which encompassed the whole of AZFb+-AZFc regions and may lead to male infertility,sperm deficiency and/or severe oligospermia.In fetus 2,CNV-seq also detected a 14.84 Mb deletion at Yq11.21-q12,which encompassed the whole of the AZF region and may lead to severe spermatogenesis disorder resulting in severe oligoasthenospermia and azoospermia.In both cases,testing of SRY gene was positive.No point mutation of the SRY gene was identified.Analysis of amniotic fluid DNA confirmed partial or total absence of AZF in the two fetuses,respectively.Conclusion Combined use of various technologies can enable accurate detection of structural abnormalities of the Y chromosome and facilitate genetic counseling.CNVseq can help with rapid screening of Y chromosome microdeletions and may be used as a complementary test for chromosomal karyotyping.

Objective To discuss the key points of endovascular therapy for complex subclavian artery occlusive diseases. Methods During the period from January 2012 to December 2013, a total of 92 patients with complex subclavian artery occlusive disease were admitted to Xuanwu Hospital of Capital Medical University, Beijing, China. The clinical data were retrospectively analyzed. The features of the lesions, the success rate of endovascular therapy, the use of combined approaches, the relief of symptoms after treatment, etc. were evaluated. Results The complex subclavian artery occlusive diseases could be divided into three types. Type Ⅰ: long segment of the left subclavian artery was occluded; type Ⅱ: ostial stenosis or occlusion of the right subclavian artery; and type Ⅲ: subclavian artery stenosis or occlusion was associated with the ostial disorder of the vertebral artery, or the opening of vertebral artery was affected by the subclavian artery stenosis or occlusion. The technical success rate was 82.6%. Combination use of femoral artery and brachial artery approach was employed in 27.2% of patients, which had improved the technical success rate. After the treatment the symptom improvement rate was 81.6%. Conclusion Upper limb artery approach can improve the re-canalization rate of left subclavian artery with long segment occlusion, and can ensure the accurate positioning of stent at the site of right subclavian artery opening. During the procedure of endovascular intervention for subclavian artery occlusion disease, attention should be paid to the protection of the vertebral artery.

AIMTo evaluate the effect of in vitro and in vivo treatment with mitomycin C (MMC) on activities of CYP2D1/2, CYP2C1 , and CYP1A2 in the liver of male rats.

METHODSUsing HPLC to determine the activities of the three isoenzymes in rat liver microsomes by detecting the specific metabolites of their substrates after treatment with inducers in vivo or inhibitors in vitro.

RESULTSIn vitro, MMC inhibited the activity of CYP2D1/2, CYP2C11, and CYP1A2 in dexamethasone-induced microsomes by (19 +/- 6)% (P < 0.05), (85 +/- 10)% (P < 0.01), and (36 +/- 6)% (P < 0.05), respectively, and decreased the activity of CYP1A2 in beta-naphthoflavone-induced microsomes by (58 +/- 6)% (P < 0.01). Rats were injected intraperitoneally with 20% of the LD50 of MMC for 3 or 6 d. The treatment showed no significant effect on microsomal activities of CYP2D1/2, CYP2C11 or CYP1A2.

CONCLUSIONMMC can inhibit the activities of CYP2D1/2, CYP2C11, and CYP1A2 in rat liver microsomes in vitro, but it showed no significant effect on the activities of the three isoenzymes in vivo.

Alcohol Oxidoreductases ; Animals ; Antibiotics, Antineoplastic ; pharmacology ; Aryl Hydrocarbon Hydroxylases ; metabolism ; Biotransformation ; Cytochrome P-450 CYP1A2 ; metabolism ; Cytochrome P450 Family 2 ; Male ; Microsomes, Liver ; enzymology ; Mitomycin ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Steroid 16-alpha-Hydroxylase ; metabolism