BACKGROUND: In the clinical therapy for orthopedic diseases, the traditional administration easily induces the great fluctuation of drug concentration and side effect, and implanted drug carrier material hydroxyapatite (Hap) cannot be used in human's load bearing parts due to its poor mechanical performances, and poly-L-lactic acid (PLLA) is effortlessly degraded to acid byproducts. Drug carriers made from Hap/PLLA are supposed to not only persist releasing drug onto the lesion and reduce the side effect,but also obtain strength enhancement and eliminate tissue inflammatory reaction in favor of bone regeneration.OBJECTIVE: To observe the preparation of absorbable target control-release drug carrier and simulate the application of drugs.DESIGN: Observation trial.SETTING: Chongqing Institute of Technology and Wuhan University of Technology.MATERIALS: Tails of albino rats and PLLA (offered by Biological Center of Wuhan University of Technology), pepsin (1:10 000, Sigma company), Ca(OH)2, strong phosphoric, NaOH, glacial acetic acid, phosphate buffer (pH=7.4), 1,4-dioxane, absolute alcohol (Analytical reagent available on market).METHODS: The experiment was carried out in Chongqing Institute of Technology and Wuhan University of Technology. ①Type Ⅰ collagen (Col)was prepared by acid dissolution and alkali purification methods. Hap/Col bone-like biomimetic composite was synthesized through self-assembly mechanism of materials simulating in vitro biomineralization process of nature bone. X ray diffraction analysis and transmission electron microscope were applied to observe the characterization of composite's structure and morphology. ②The resultant product of HAP/Col composite was further synthesized with PLLA to prepare the three-dimensional porous reservoir type carrier for controlled release of drug employing thermal-induced phase separation technique. Scanning electron microscope, material test machine and specific gravity test method were used to investigate the pore structure and mechanical property of carrier material. ③The prepared Hap/Col/PLLA drug carrier was loaded with bromothymol blue to investigate in vitro control-release characteristic in simulated body fluid.MAIN OUTCOME MEASURES: ①Characterization of structure and morphology of Hap/Col bone-like biomimetic composite; ②Evaluation on the property and preparation technique of Hap/Col/PLLA drug carrier; ③Assessment on results of in vitro control-release trail of model composite.RESULTS: ①Hap nanocrystals formed as slender needles aligning with its crystalline c-axis preferentially oriented.②Hap/Col/PLLA drug carrier possessed apt pore configuration and physical properties for drug controlrelease.③In vitro release test by model compound revealed an approximate zero-orderslow release prior to its 80% release percentage.CONCLUSION: Hap/Col composite material is similar with natural bone, and Hap/Col/PLLA reservoir carrier can control drug release.

Objective To investigate the change in expression of hippocampal neuronal 5-hyroxytryptamine1A(5-HT1A) receptor in a mouse model of chronic restraint stress.Methods Forty BALB/c male mice aged 6-9 months weighing 25-35 g were randomly divided into 2 groups ( n =20 each): normal control group (group C) and chronic restraint stress group( group S).In group S,the model of chronic restraint stress was established described by Wood et al.Tail suspension test,light-dark test and Morris water maze test were performed respectively at 1 d after successful establishment of the model.Immobility time,staying time in light compartment,and escape latency and frequency of crossing the original platform were recorded respectively in tail suspension test,light-dark test and Morris water maze test.Then the animals were sacrificed,hippocampi were removed for determination of the expression of 5-HT1A receptor in CA1 and CA3 regions of hippocampal neurons by immuno-histochemistry.ResultsCompared with group C,immobility time and escape latency were significantly prolonged,staying time in light compartment was shortened,frequency of crossing the original platform was decreased,and the expression of 5-HT1A receptor in hippocampal neurons was down-regulated in group S ( P ＜ 0.05 or 0.01 ).ConclusionChronic restraint stress can induce cognitive impairment in mice by down-regulating the expression of 5-HT1A receptor in hippocampal neurons.

ObjectiveTo investigate the effect of remifentanil on hepatic ischemia-reperfusion (I/R) injury in rats with liver cirrhosis.MethodsThirty male SD rats weighing 260-300 g were randomly divided into 3 groups (n =10 each):group liver cirrhosis (group C); group liver cirrhosis + hepatic I/R (group I/R) and group remifentanil (group R).Liver cirrhosis was produced in all animals in the 3 goups.I/R injury was induced by 20 min occlusion of the hepatic artery and portal vein entering the middle and left lobes of the liver followed by 4 h reperfusion at 1 week after establishment of hepatic cirrhosis in I/R and R groups.In group R remifentanil was infused iv at 1 μg·kg-1 ·min-1 starting from 10 min before ischemia until the end of 4 h reperfusion.Venous blood samples were taken from inferior vena cava at the end of 4 h reperfusion for measurement of serum ALT and AST activities.The animals were then sacrificed and liver specimens were taken from middle lobe for determination of Bcl-2 and Bax expression (by immuno-histochemistry) and hepatocyte apoptosis (by TUNEL) and microscopic examination.Apoptosis index (percentage of apoptotic cells) was calculated.ResultsI/R significantly increased serum ALT and AST activities,Bax expression and apoptosis index and decreased Bcl-2 expression in group I/R as compared with group C.Remifentanil significantly attenuated the I/R-induced changes in serum ALT and AST activities,Bax and Bcl-2 expression and apoptosis in group R as compared with group I/R.Remifentanil also ameliorated I/R-induced liver damage.ConclusionRemifentanil can auenuate hepatic I/R injury in rats with liver cirrhosis by up-regulating Bcl-2 expression and down-regulating Bax expression and inhibiting apoptosis.

Objective To investigate the influence factors of birth defects. Methods The congenital malformational fetuses born from 13 week of gestation to 7 days after birth were selected as the study group between April 1st, 2009 and March 31st, 2010. The health born fetuses were set as control in the same period. Case-control and the three-level of monitor network of birth defects were used in the study in the participating 75 hospitals (Qingdao Women and Children's Medical Center, Affiliated Hospital of Medical College Qingdao University, Qingdao Municipal Hospital, etc.) . The study and control group's parents were interviewed by an uniformed questionnaire which was designed specially with influence factors of birth defects. Results (1) There are 466 congenital malformational fetuses in the total of 77 231 fetuses collected in 75 hospitals. The congenital malformational rate accounts for about 6. 034‰. The top six defect diseases were congenital heart disease (112 cases) , total harelip (cleft lip; cleft lip with palate; 85 cases) ,polydactyly (53 cases) , neural tube defects (38 cases) , congenital hydrocephalus (37 cases) and limb reduction defect (27 cases) in turn, which amounts to 353 cases (54.48% , 353/648). (2) Their mother education level in the birth-defect group (25. 6%) were significantly lower than that in control group (30. 0% , P < 0. 05). (3) The rate of passive smoking, drinking, raising pets of the parents in birth-defect group were significantly higher than that in control group (P < 0. 05). (4) The rate of exposure to harmful chemical and physical factors of mothers in birth defects group (13.9% and 20. 5% , respectively) was higher than that in control group (1.1% and 11.7% , respectively) , the difference between which were significant (P < 0. 01) . The rate of disease (34. 3%) , fever (13. 1%) , taking drugs (33. 8%) in pregnancy period in birth defect group were higher than that in control group (13. 5% , 1.5% and 9. 9% ,respectively) , the difference between which were significant (P <0. 01). The rate of bad moral irritation to the mother in pregnancy in birth defect group (11. 3%) was significantly higher than that in control group (1.4% , P<0.01). (5) There were 19 cases (2.9% , 19/648) with family heredity medical history in birth defect group, but there were none in the control group, the difference between which were significant (P<0. 01). There were 89 cases (13.7% , 89/648) with unusual birth history of their mothers in birth defect group, but there were 31 cases (4. 8% , 31/650) in control group, the difference between which were significant (P<0. 01). (6) Conditional Logistic Regression model was used for univalent and multivariate analysis. The results showed that main influence factors were identified as having important effect on birth defects, including mothers' exposure to harmful chemical factors (OR=13. 46) , disease (OR=3. 37) ,taking drugs (OR=2. 20) , exposure to bad moral irritation (OR=5. 44) , food-choosy (OR=1. 90) ,anemia (OR=1. 52) in gestational period, polyembryony (OR=4. 40) , father drinking (OR=1. 55) .While it was protective factors to supplement microelements such as the calcium iron and nutrient, etc. in pregnancy period (OR=0. 45). Conclusions First, the main birth defects were congenital heart disease, total harelip (cleft lip; cleft lip with palate) , polydactyly, neural tube defects, congenital hydrocephalus and limb reduction defect in turn. Second, the main influence factors identified as having important effect on birth defects were mothers' exposure to harmful chemical factors, ill, taking drugs, exposure to bad moral irritation, food-choosy, anemia in gestational period, polyembryony, father drinking. But it is protective factors to supplement microelements such as the calcium iron and nutrient, etc. in pregnancy period. Finally, it is the important part to prevent the birth defects by reducing and controlling dangerous factors in pregnancy period.

Objective Based on the theory of Service Quality to develop a scale for measuring personal digital assistant satisfaction by nurses and to detect the reliability and validity of this scale. Methods Through the literature research, cross-sectional study and present satisfaction evaluation tool for using personal digital assistant by nurse to build the item pool. The items were selected by 15 experts consultation and the pilot survey of 666 nurses. Results The satisfaction evaluation tool for using personal digital assistant by nurse scale consisted of 41 items;the exploratory factor analysis identified 8 principal factors and explained for 65.22%. Pearson correlation coefficient between each dimension was 0.213-0.684(P<0.01). Pearson correlation coefficient between each dimension and total scale was 0.574-0.798(P<0.01). The Cronbach α coefficient of the scale was 0.928 and test-retest reliability was 0.934. Conclusions The satisfaction evaluation tool for using personal digital assistant by nurse scale has good validity and reliability. It can be used as a tool to measure the satisfaction for using personal digital assistant by nurse.

Three cases of terminal stage heart disease received orthotopic heart transplantation at the Department of Cardiothoracic Surgery, the First Hospital of Nanchang University between August 2001 and December 2003. These three cases were all female and died of brain death. Body weight difference between donor and recipient was less than 20%. All three cases underwent superior and inferior vena cave osculation and received immunosuppressive therapy of cyclosporine A, prednisone, and mycophenolate postoperatively. They were successfully discarded. Heart function recovered to grade Ⅰ-Ⅱ(NYHA). No infection or serious rejection was found during the surgery. These results indicate that good donor heart preservation, consummate perioperative processing, and proper immunosuppressiva therapy are the key measures of successful heart transplantation.

Objective To explore the effect of miR-200b on chemosensitivity of cervical cancer HeLa cells to paclitaxel and its mechanism.Methods A recombinant miR-200b mimics was transfected into cultured HeLa cells,which were divided into observation group,negative group,and blank control group.Each group was treated with different concentrations of paclitaxel.Methyl thiazolyl tetrazolium (MTF) assay was performed to evalate the proliferative ability of these treated cells to paclitaxel.AnnexinVFITC/PI method was used to detect the apoptosis rate of Hela cells.The protein level of vascular endothelial growth factor (VEGF) was detected by Western blot.Results MTT assay showed that the OD values of three groups were totally different;and compared to the other two groups,the OD value of the transfected HeLa cells was significantly lower (P ＜ 0.05).Compared to the negative group and the blank control group,there was no statistical difference (P ＞ 0.05).AnnexinV-FITC/PI results demonstrated that the apoptotic index of the transfected HeLa cells was significantly higher than that in the other two groups (P ＜0.05).Western blot assay showed that expression of VEGF protein in three groups of relative quantity was 0.403 ± 0.046,0.882 ± 0.094,and 0.901 0.102,respectively.There was significant difference among there groups (P ＜ 0.05).Conclusions miR-200b mimics can increase the sensitivity of cervical cancer HeLa cells to paclitaxel,and targeted regulation of VEGF may be the cause of increasing in drug sensitivity.

The PDLLA/HA compound fibers with excellent properties could be obtained by melt-spinning. This study inquired about the mechanical properties, change rule and influencing factors. The results showed that the composites fibers of mechanical properties were good in the PDLLA(molecular weight 120,000) to which were added the 4-20 microm HA particles. In the matrix of PDLLA with accretion (10%) of HA particles, the tensile strength of the compound fibers was the highest, compared with the others. The tensile strength of the compound fibers of PDLLA (molecular weight 20,000-300,000) was high. The tensile strength of the compound fibers decreased with the increase of the fiber diameter, and the PDLLA/HA fibers 40-60 micrometers in diameter had the highest elongation at break.
Biocompatible Materials ; chemistry ; Bone Substitutes ; chemistry ; Durapatite ; chemistry ; Lactic Acid ; chemistry ; Polyesters ; Polymers ; chemistry ; Tensile Strength ; Tissue Engineering ; methods

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