Objective:To observe the elimination of smear layer on the dentin exposed to Er,Cr:YSGG laser with different energy and irradiating distance. Methods:The in vitro first premolar was selected and slices with 1.5 mm thickness were obtained by horizontal sectioning through the middle third of the teeth crown using a high-speed bur. Each dentinal slice was irradiated under the laser with different irradiating distance(

Objective To observe the surface morphology of dentin irradiated by Er,Cr∶YSGG laser under anhydrous conditions and discuss the possible clinical applications of the laser.Methods 11 freshly extracted specimens (approximately 1.5 mm thick) taken from the first premolars were selected.One was regarded as the control group without any treatment and the remaining ten were divided into 5 groups whose dentin surface was irradiated by Er,Cr∶ YSGG laser with different energy (1,2,3,4,6 W) under anhydrous condition.The specimens were routinely prepared for electron microscopic scanning observation.Results As the output power increased with Er,Cr∶YSGG laser irradiation,the dentin surface was observed of the constriction of tubular lumen,and part of the tubules closed.The dentin surfaces with 3 ～6 W laser irradiation were observed thermal injury alters such as micro crack and carbonization.Conclusion 1 ～2 W anhydrous Er,Cr:YSGG laser irradiation play a more ideal and safe constriction and sealing role to dentinal tubules,and the laser is expected to be used for the treatment of dentin hypersensitivity.

Objective To investigate the apoptosis induction effect of recombinant caspase-3 expression on osteosarcoma cell line SOSP-9901. Methods Recombinant caspase-3 gene was subcloned into the GFP reporter vector pEGFP-C1 to generate the expression vector pEGFP-caspase-3 by DNA recombinant technique. pEGFP-caspase-3 was transfected into human osteosarcoma cell line SOSP-9901 by Lipofectamine 2000. The expression of recombinant caspase-3 was determined by RT-PCR. The morphological changes of transfected cells were observed under flurescent and electronic microscope. The cell survival rate of transfected cells was assayed by MTT method. Results Recombinant caspase-3 gene could be stably expressed in the transfected SSOP-9901 cells. Recombinant caspase-3 could obviously induce SOSP-9901 apoptosis, and inhibit SSOP-9901 cell proliferation in vitro. Conclusion Recombinant caspase-3 could inhibit the growth of the osteosarcoma cell line SOSP-9901 and induce it into apoptosis.

Objective To investigate the effect of acute high intracranial pressure on the static pressure-volume curve of dogs' total respiratory system in order to evaluate the relationship between brain injury and respiratory insufficiency.Methods Fourteen dogs were divided into two groups.Animals were anesthetized,paralyzed and mechanical ventilated.The intracranial hypertension in experimental group(n=8)was induced by injecting blood-clots into the right frontal lobe.The other six dogs served as control.The intracranial pressure was monitored by an optical fiber transmitter inserted into the left cerebral hemisphere.The pressure-volume curves of the respiratory system were measured before and after induction of high intracranial pressure by a self-made apparatus consisting of two sealed bottles and a U shaped glass tube.The curves were also measured correspondingly in control group.The static compliance was calculated by equation C=?V/?P.The volume of intracerebral hematoma was calculated.The histopathology of lung was studied under microscope.Results The intracerebral hematoma was located in the right frontal lobe with volume from 4.8-11.5ml(average 8.48ml).The intracranial pressure was elevated from 18.13?5.96mmHg to 46.88?16.42mmHg,which induced a shift of pressure-volume curve to the right in experimental group,while no obvious change was found in control group.Compared to pre-injection,the static compliance of total respiratory system decreased significantly(P

Objective Face-down positioning after vitrectomy and gas tamponade is still the standard position for patients with rhegmatogenous retinal detachment.The study was to compare the nursing effects of face-down position and flexible position after vitrecto-my for the repair of rhegmatogenous retinal detachment. Methods We investigated 120 cases of patients with rhegmatogenous retinal detachment in this study.All patients received vitrectomy with long-acting gas for tamponade, 60 patients in face-down position and 60 in the flexible position.Patients were followed up for 6 months.Observation was made on the rates of anatomical retinal reattachment and postoperative complications between the groups. Results The rates of anatomical retinal reattachment after surgery were 88.33%in the face-down position group and 100% in the flexible position group respectively.As to the satisfaction of position, the flexible position group was 100%, which was much higher than 41.67%in face-down position group(P<0.01). Conclusion Flexible position nurs-ing after vitrectomy and gas tamponade for rhegmatogenous retinal detachment repair is safe and effective.Flexible position can replace face-down position for the comfort of patients with rhegmatogenous retinal detachment after vitrectomy with gas tamponade.

Child ; Child, Preschool ; Computer Systems ; Humans ; Phylogeny ; Polymerase Chain Reaction ; methods ; Respiratory Syncytial Viruses ; genetics ; isolation & purification ; Reverse Transcriptase Polymerase Chain Reaction ; methods

[Objective] To construct a database for the genetic polymorphism of 18 STR loci (D8S1179, D21S11, D7S820, CSFIPO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, VWA, TPOX, D18S51, D5S818, FGA, PentaE, PentaD, SE33) in Hart population from Zhejiang province. To investigate the application of 18 STR loci in the field of paternity testing and prenatal diagnosis. [Methods] Fluorescent dye labeling multiplex STR-PCR, capillary electrophoresis and DNA sequencer GeneScan were adopted in genotyping 598 unrelated samples collected from Han population in Zhejiang province. 18-STR database was established and analyzed. Population comparison was conducted between Han population in Zhejiang province and 8 other population. 15-STR and 18-STR identification system were compared in 497 paternity testing cases. [Results] We observed the distribution of 18 STR loci in Han population meet Hardy-Weinberge equilibrium and was different from other 8 population (X~2 test, P>0.05). Statistical results showed that the heterozygosis (He) ranged from 0.630 to 0.942. The combined power of discrimination was>0.9999999999. Compared with 15-STR identification system, higher paternity index scores and higher exclusion rate were obtained with 18-STR identification system in dual-case paternity test and mutation identification. One trisomy 21 fetus was found in a prenatal paternity test case which had two characteristic genotypes in 2 STR loci of D21S11 and Penta D. [Conclusions] The 18 loci were relatively highly genetic polymorphic in Zhejiang Han population and could be used for paternity testing. Some STR loci could be used in prenatal diagnosis for aneuploidy.

Objective To examine the effect of Caffeine on the cultured cortical neuron apoptosis in neonatal rats.Methods The primary cerebral cortex neurons for cultures were obtained from neonatal mice 2-3 days after birth,Caffeine reconstituted at final concentrations 300μmol/L and 1 000μmol/L was added to the cell cultures and continuously co-incubated for 6-36 h,respectively after the cortical neurons were continuously cultivated 7 days after incubation under temperature of 37℃ incubator with 5% CO_2 and 100% relative humidity,the intracellular calcium concentration,mitochondrial membrane potential and apoptosis rate were determined by the flow cytometry.The activity of Caspase-9 was assayed by enzyme-labeled instrument,and Caspase-9 activity by the enzyme-1inked analyzer.Cell morphological changes were observed under electron microscope and fluorescent microscope after being stained with Hoechst 33258 fluorescent dye.Results Compared with the control group,the average increase in intracellular calcium fluorescence intensity was most significant(P<0.05),which elevated from the normal value 43.13±2.02 to 45.28±1.16 and 46.92±1.99,respectively at 6 h;mitochondrial membrane potentials were reduced most significandy(P<0.05).from the base value 443.58 ±11.77 down to 289.53±16.47 and 165.14±14.72,respectively at 8h.Caspase-9 activity was peaked(P<0.05),from the normal value 1.00±0.000 to 5.33±1.02 and 8.33±0.92,respectively at 10 h.The neuronal apoptosis ratio was increased significantly (P<0.05),from the normal value 4.94±1.74 to 15.98±2.03 and 18.70±2.09,at 36h.The apoptotic bodies were observed at 24 h after administration of 300 μmol/L and 1000 μmol/L Caffeine.Conclusion Caffeine may promote neuronal apoptosis in neonate mice.

Objective To study CD40 expression on melanocytes induced by IFN-?and its significance. Methods CD40 expression was detected by flow cytometry. The capacity of melanocytes to stimulate T lymphocytes was evaluated by mixed ly mphocyte reaction and the supernatant cytokine levels were determined by ELISA. ResultsHuman melanocytes(MC) cultured in vitro expressed low but detectable CD40 surf ace protein. The surface expression of CD40 was markedly up-regulated by stimul ation with interferon(IFN)-?with different concentrations for 24 hours,48 hour s and 72 hours, respectively. The expression of CD40 was correlated with IFN-? levels after 24 hour incubation. MC underwent a morphologic change with an incre ased capacity to stimulate allogenic lymphocytes to proliferate after IFN-?sti mulation. Optimal enhancement of stimulating index(SI) was observed at an IFN-?concentration of 300 IU/ml after 72 hour treatment. Meanwhile concentrations o f interleukin-12 but not interleukin-8 or 10 were obviously increased in the s upernatants of cultured MC. Furthermore, ligation of CD40 via soluble CD40 ligan d(SCD40L) could enhance CD80 and ICAM-1 expression, which could be blocked by s pecific monoclonal antibody to CD40L. Conclusions Since CD40-CD40L is a pair of important and special costimulating signal, it is of great value to elucidate t he fact that CD40 is functionally expressed on MC, thus for a better understandi ng of MC′s role in cellular immune responses. MC might activate cytotoxic T lym phocyte directly and not via CD4 positive lymphocyte.

Adolescent ; Anti-Asthmatic Agents ; therapeutic use ; Asthma ; blood ; drug therapy ; Child ; Child, Preschool ; Female ; Glucocorticoids ; therapeutic use ; Humans ; Infant ; Interleukin-23 ; blood ; Male