Transposons are the mobile and autonomic replication DNA fragments in genomes. With more understanding of the structure and function of transposons, numerous transposons have been developed to the genetics tool for gene function analysis, gene transformation and gene therapy. The low transpositional activity of the natural transposons is the main obstacles to the utilization of transposons. Recently, with the progress in bioinformatics and protein engineering methods, researchers have reconstructed and optimized natural transposases to create hyperactive transposases that catalyze the transposition with high efficiency. The resulted hyperactive transposons have been applied to gene-modification and gene-tagging. Meanwhile, transposase chimeras were created by protein fusion technology. The insertion characteristic of transposons were artificially regulated which could be utilized in gene therapy.
DNA Transposable Elements ; Gene Targeting ; Genetic Therapy ; Protein Engineering ; Transposases ; chemistry

AIM:The complications following liver transplantation consist of the liver damage and the function failure of other organs,among which lung is the most prone and the earliest affected lesion.By establishing an autologous orthotopic liver transplantation(OLT) model in rats,this study was to investigate the acute lung injury after liver transplantation and the role of alkaline phosphatase(AP) in protection of the injury.METHODS:①The experiments were performed in the Test Animal Center and Digestion Laboratory,Nanfang Hospital,Southern Medical University from May to October in 2007.All the proposals were in accordance with the ethical standard of animals.② Twenty-four SD rats were randomly divided into three groups:sham-operation control group,autologous OLT group and AP group,each containing 8 animals.Autologous OLT models were induced in OLT group and AP group,while control group,the abdomen was only opened and then closed besides the liver lobes were isolated.Lingual vein injection of AP was given in AP group 5 minutes before the blood supply of the liver restored.③The concentration of myeloperoxidase(MPO),malondialdehyde(MDA) and surfactant protein A(SP-A) in lung tissue were respectively examined in each group,lung dry-to-wet weight ratio was also measured.Furthermore,hepatic and lung pathological sections were observed.RESULTS:All the 24 rats were involved in the result analysis.①Compared to control group,the concentration of MPO and MDA in lung tissue were significantly increased in OLT group and AP group(P

Objective To investigate whether the early use of tetramethylpyrazine(TMP) could improve the oxygenation ,reduce the rate of pulmonary lesion ,increase the survival rate and shorten the hospital days in the patients with severe acute pancreatitis (SAP) .Methods A total of 42 patients with SAP were randomly divided into the control (C) group(21 cases ,receiving the conven-tional treatment combined with the respiratory support treatment ) .The TMP group(21 cases ,receing the conventional treatment , respiratory support and TMP treatment ) .Results In the C group ,6 cases were intubated(28 .57% ) ,9 cases were acute respiratory distress syndrome(ARDS)(42 .86% ) ,the survival rate was 80 .95% ,the average hospitalization was (21 .6 ± 7 .3)d;in the TMP group ,3 cases were intubated(14 .28% ) ,6 cases were ARDS(28 .57% ) ,the survival rate was 85 .71% ,the average hospitalization was(17 .9 ± 6 .4)d .The survival rate had no statistical difference between the two groups (P>0 .05) .In addition ,the TMP group was superior to the C group in the average hospital days .Conclusion Eerly TMP interrention significantly reduced the rate of endo-tracheal intubation and the occurrence rate of ARDS ,shorten the hospital days ,but without increasing the survival rate .

The afferent connections of the preoptic region in the rat were studied with retrograde horseradish peroxidase (HRP) method.The mico-injection syringe needle or microelectrophoretic pipette was inserted vertically into the brain. In some cases, the injection was made with the needle inclined and directed contralaterally or in inclined direction through the cerebellum.The results were as follows:Following HRP injection into the medial preoptic area, labeled neurons were found in periventricular hypothalamic gray, paraventricular nucleus, anterior hypothalamic nucleus, supraoptic nucleus, ventromedial hypothalamic nucleus, posterior hypothalamic nucleus and locus coeruleus in all cases. In some cases, labeled cells were also observed within bed nucleus of stria terminalis, dorsal raphe nucleus. In addition, in a few cases, a small number of labeled cells could be found in lateral septal nucleus, medial septal nucleus, periaqueductal gray matter and interpeduncular nucleus.After injection into the region between the medial and lateral preoptic area, besides the above mentioned labeled nuclei, there were still a number of labeled cells found in paratenial nucleus, nucleus reuniens and lateral hypothalamic nucleus, in some cases also found in the supramammillar nucleus, and in one case even in the cortical and medial amygdalar nuclei.Following the injection of HRP into the anterior hypothalamic nucleus, retrograde labeling of neurons was observed within the lateral septal nucleus, preoptic periventricular nucleus, medial preoptic nucleus, supraoptic nucleus, periventricular hypothalamic nucleus, paraventricular nucleus, ventromedial hypothalamic nucleus, periaqueductal gray matter and locus coeruleus in all cases. Among them, supraoptic and paraventricular nuclei were labeled bilaterally in some cases.

Fifteen liposoluble compouuds were isolated and identified from the rhizomes of Drynaria fortunei (Kunze) J.Sm.. They are: diploptene(Ⅰ); hop-21-ene(Ⅱ); diplopterol(Ⅲ); fern9(11) -ene(Ⅳ); cyclolaudenol(Ⅴ); cyclomargenol(Ⅵ); cyclolaudenone (Ⅶ); n-dotriacontanic acid(Ⅷ); ?-sitosterol(Ⅸ); 25-en-cycloartenol(Ⅹ); 25-en-cycloartenone(Ⅺ); 24-en-cycloartenol(Ⅻ); 24-en-cycloartenone; 5-stigmasten-3-ol; 5-stigmasten-3-one Apart from Ⅰ,Ⅳ and Ⅸ, the rest had not been found in this fern since.

Objective To develop an ion chromatography (IC) for simultaneous determination of chlorite,chlorate and bromate in drinking water. Methods The IC separation was carried out with the IonPAC AS23 column by using 4.5 mmol/L Na2CO3-0.8 mmol/L NaHCO3 at the flow rate of 1.0 ml/min. The injection volume was 250 ?l,the temperature of conductivity detector cell and column were 30 ℃ and 35 ℃,respectively. The pressure upon the bottle of mobile phase was 40 kPa. The current of auto-regenerating suppressor was 25 mA. Results The results showed that in the range of 0 to 1 000 mg/L, the calibration equation for chlorite was y=0.009 6+1.600 0 x (r=0.999 3),for bromate was y=0.003 2+3.184 7 x (r=0.999 9),for chlorate was y= 0.001 8+1.788 9 x(r=0.999 9).The detection limit of chlorite,chlorate and bromate were all 5 ?g/ L,the recovery rates were 89.0% -108.0% and the relative standard deviations (RSD) were 0.21%-2.70%. Conclusion The method is simple,fast,accurate, sensitive,little interference and is applicable to the simultaneous determination of chlorite,chlorate and bromate in drinking water.

The changes of oxygen saturation (SaO_2) and cardiac index (CI) of 23 soldiers who had stayed in a simulated high altitude of 4 000m and 5 000m for 72 hours were observed with a Model 102 BIT BIOX IIA earprobe oximetry and impedance cardiogram. It was found that both SaO2 and CI decreased because of hypoxia, and the decrease became more severe with the elevation of the altitude and the prolongation of staying. At the end of the 24th hour of staying, the 2 parameters reached the lowest. These facts suggest that hypoxia more or less depresses the cardiac function. Four hours after the subjects returned to sea level, SaO2 restored the normal value but CI remained significantly lower than the control valuet which implies that the effects of acute hypoxia still existed at that time.

The tissue engineering heart valve(TEHV) is a kind of procthetic valve that possesses the characteristics of living, self-repair and proliferation. Owing to the specific properties that are the better hemodyna-mics, low or even no immunological reaction, no need for long-time anticoagulation therapy and longer durability, the ideal TEHV can overcome the drawback of current available valve substitutes which are mechanical prostheses and biological heart valves. In this paper we reviewed the recent development of the TEHV in such aspects, as biomaterial, cultivating environment, seed cells and so on. In addition, we briefly introduced the perspective of using human embryonic stem cells as the source for seed cells in TEHV.

Congenital cataract is a common eye disease which leads to children low vision. Surgery is the main treatment. Because of children's preoperative evaluation, operation, postoperative management is more difficult than adult, the outcome of surgery is not so well. Therefore, we review the relevant congenital cataract surgery researches in recent years in order to discuss the problems and further developments in this area.