BACKGROUND:Related studies have showed that poly D,L-lactide-co-glycolide can effectively package antisense oligonucleotides, smal interfering RNA, microRNA. Poly D,L-lactide-co-glycolide can better protect them against the destruction of the enzymes in vivo and have slow the drug release. Therefore, the number of drug administration can be reduced to achieve a long-term and effective therapeutic effect. ＜br> OBJECTIVE:To prepare poly D,L-lactide-co-glycolide-CXCR4-miRNA-nano-particles and to research the characteristics of the prepared nanoparticles. ＜br> METHODS:Poly D,L-lactide-co-glycolide-CXCR4-miRNA nanoparticles were prepared by double emulsion-evaporation process. Ultraviolet spectrophotometry was utilized for measurement of encapsulation efficiency and drug-loading rate, observing the shape of nanoparticles by transmission electron microscope, and measuring the size and distribution of nanoparticles by laser particle size analyzer. Sustained-release characteristics of nanoparticle suspension were observed in phosphate buffer. ＜br> RESULTS AND CONCLUSION:The prepared nanoparticles were spherical-shaped, smooth, evently distributed and inadhesive. The particle size was mainly distributed within 143-502 nm, with an average diameter of 280 nm. The average drug loading was (0.515±0.023)%, the average encapsulation ratio was 50.2%and difference between batches was smal . The nanoparticles could slowly release in vitro and the process initial y experienced the fast-release stage, and then reached a basical y stable platform stage at day 14. These finding indicate that the process to prepare poly D,L-lactide-co-glycolide CXCR4-miRNA-nanoparticles by double emulsion-evaporation is simple. The prepared nanoparticles are wel targeted and exhibit sustained-release effects.

Objective:To investigate the effect of Vitapex paste in the root canal for deciduous teeth with chronic apical periodontitis.Methods:200 children with chronic apical periodontitis were selected and divided into two groups.The observation group (108 cases)was given Vitapex paste.The control group (92 cases) was given Zinc oxide iodoform paste.The effect of Vitapex paste in root canal for deciduous teeth with chronic apical periodontitis was evaluated by filling quality after 1 month'treatment,the VAS scores before and after treatment,long-term curative effect were compared between two groups.Results:After 1 month'treatment,the suitable filling rate of observation group was higher than that of the control group(P＜0.05).There was no statistical significance in the VAS scores between two groups (P＞0.05).After 1 week'and 1 month'treatment,the pain feeling were alleviated in two groups and significantly lighter in the observation group(P＜0.05).After 6 months' follow-up,the success rate was 96.3％ in the observation group and 87.0％ in the control group,the success rate of observation group was higher than that of the control group (P＜0.05).Conclusion:The filling process of Vitapex paste was simple and easy,which had a good therapeutic effect on chronic apical periodontitis of deciduous teeth and could relieve the toothache of patients.

AIM: To observe the changes in subfoveal choroidal thickness ( SFCT ) after intravitreal injections of ranibizumab ( IVR ) for macular edema secondary to retinal vein occlusion ( RVO) .
METHODS:Thirty-six eyes of 36 patients with macular edema secondary to RVO) were treated with 0. 5mg IVR monthly for 3mo and received additional IVR as needed over the following 1a period. SFCT of the all eyes ( the affected eyes with RVO and unaffected fellow eyes ) was measured by enhanced depth imaging optical coherence tomography images before and after the IVR.
RESULTS: The mean SFCT of the affected eyes with RVO decreased from 246. 7±115. 0μm at baseline to 220. 5±102.0μm at 1mo (P<0.05), 198.3± 114.0μm at 6mo (P<0.01), 212. 6± 96. 0μm at 12mo (P<0. 01). Whereas the fellow eyes changed from 229. 4±108. 0μm at baseline to 226. 3±107. 0μm at 1mo (P>0. 05), 228. 6±127. 0μm at 6mo (P>0.05), 223.6±101.0μm at 12mo(P>0.05). There were statistically significant difference between affected eyes with RVO and unaffected fellow eyes.
CONCLUSION: The SFCT is decreased after IVR for macular edema secondary to RVO. IVR seems to affect the hemorheology of the choroid.

Objective To evaluate the effects of transforming growth factor β1 (TGF-β1 )on migration, adhesion and proliferation of periodontal ligament stem cells (PDLSCs)and explore the mechanisms of PDLSCs-induced periodontal remodeling.Methods PDLSCs were isolated and identified from human teeth.The effect of TGF-β1 on migration of PDLSCs was evaluated using transwell migration assay.Cells attachment assay was used to test the effect of TGF-β1 on the adhesion of PDLSCs.In addition,the effect of TGF-β1 on the proliferation of PDLSCs was evaluated by MTT and cell growth rate assay.Results The results showed that TGF-β1 induced the migration of PDLSCs in a dose-dependent manner,improved the adhesion and proliferation of PDLSCs.So we propose that TGF-β1 may promote periodium remodeling by inducing PDLSCs migration,following adhesion and proliferation in these areas.Conclusion This study demonstrated for the first time that TGF-β1 increases the adhesion and migration of PDLSCs in vitro .The signal pathway is involved in the TGF-β1-induced migration of PDLSCs and the mechanical-chemical interaction during the orthodontic periodontal remodeling will be researched in our further studies.

ObjectiveTo verify the reliability of the mouse model of cerebral cortical microinfarct induced by two-photon microscopy and to explore its pathological changes.MethodsSeventeen male C57BL/6J mice were randomly divided into a microinfarct group (n=11) or a sham operation group (n=6).A thinned cranial window of 3 mm diameter was performed over the cerebral cortex with a high-speed micro-drill until the small blood vessels were clearly observed under a dissecting microscope.Then, a permanent single cortical penetrating arteriole occlusion was induced with a gradually enhanced ultrashort laser irradiation through the thinned cranial window with two-photon microscopy.At 7 days after modeling, the cerebral microinfarct volume was measured with HE staining, and the neuron loss, activation of glial cells and deposition of 3-nitrotyrosine were assessed using immunohistochemistry.ResultsThe target vessels of cerebral cortex in 8 (72.7%) mice were occluded and the microinfarcts formed in the microinfarct group, and the average microinfarct volume was 317.23±20.29 μm3.There were remarkable neuron loss and microglia infiltration in the infarcted core, a large number of reactive astrocytes surrounding the infarcted lesion, and massive deposition of 3-nitrotyrosine in the peri-infarct area.No infarcts were observed in the sham operation group.The deposition of 3-nitrotyrosine in the sham operation group was significantly less than that in the microinfarct group (8.00±1.48 vs.98.38±9.10;t=23.962, P<0.001).Conclusions The mouse model of cerebral cortical microinfarct induced by two-photon microscopy is reliable, and its histopathologic changes are consistent with the pathologic features of cerebral microinfarct.

Objective To investigate the waveform of the first-order kernel and second-order kernel of muhifocal electroretinogram stimulated with light emitting diode(LED).Design Prospective,noncomparative,interventional case series.Participant 18 subjects(18 eyes)who had been accepted the mfERG test.Method The patients were devided into two groups,they accepted the muhifocal elec- troretinogram(mfERG)stimulated with cathode ray tube(CRT)and LED using the Roland RETI Scan3.15 system.The first-order kernel or the second-order kernel was analyzed.The stimulation time of LED were changed from 1.7ms to 16.7ms.Five different stimulation time of LED in this study were 1/10(1.7ms),3/10(5ms),5/10(8.3ms),7/10(ll.7ms)and 10/10(16.7ms).Main Outcome Measure The summed responses were observed.The waveform,amplitude and implicit times of mfERG summed response were analyzed.Result The waveforms of the first-order kernel stimulated by LED were similar to those of CRT.In the second-order kernels of mfERG,the wave- forms were obviously different from those stimulated by LED and CRT.The P1 wave stimulated by CRT was sharp,but the P1 wave of LED was broad.The N2 wave of LED was deeper.The amplitude of N1 wave and P1 wave were increased,and their implicit times pro- longed with the stimulation times prolonging.Conclusion In the first-order kernel of mfERG,the waveform of the summed response stimulated by LED was similar to that of LED.In the second-order kernel of mfERG,the waveform stimulated by LED was more com- plicated,may be there were more inner retina information.(Ophthalmol CHN,2006,15:351-355)

The article summarized the teaching experience to cultivate the capability of writing the standardized diagnostic imaging reports in the internes of the medical imaging speciality.The need and content of diagnostic imaging reports was standardized.The skill to read image and the capability to write the standardized diagnostic imaging report was cultivated gradually by three phases composed of the accidence phase,and the improve phase and the practice phase.

Objective To explore the changes of CD40 and CD40 ligand(CD40L) levels and investigate their significances in children with graft-versus-host disease(GVHD)after related-donor human leukocyte antigen(HLA) matching allogeneic hematopoietic stem cell transplantation(HSCT).Methods Nineteen patients with ?-thalassemia major and 1 patient with congenital inherent hemolytic anemia accepted umbilical cord blood transplantation(UCBT) and allogeneic peripheral blood stem cell transplantation(allo-PBSCT),respectively,and all cases were received successfully related-donor human leukocyte antigen matching allogeneic HSCT.Peripheral blood samples were obtained before and after transplantation,the time when GVHD happened,the expressions of CD40 and CD40L were measured by using immunofluresence asssy.Results Four UCBT children and 3 allo-PBSCT children had no acute GVHD.Thirteen children had acute GVHD(degreeⅠ-Ⅳ),the expressions of CD40L on CD4+ and CD8+ T cells in the patients with acute GVHD increased,especially in allo-PBSCT.Five cases of UCBT and 12 cases of allo-PBSCT patients had chronic GVHD,the expressions of CD40L+,CD25+ and CD69+ on CD4+ and CD8+ T cells in patients with chronic GVHD increased obviously.The expression of CD19+CD40+ was lower than normal within 3 months after transplantation.Conclusions The high expression of CD40L+T cells in periferal blood after HSCT was related to the activation and proliferation of T cells in the development of GVHD in HSCT.

Objective To evaluate the efficacy of radiosynovectomy with 32P colloid in haemophilic synovitis of adolescents. MethodsRadiosynovectomy with 32P colloid was primary performed on 26 male haemophilic patients(26 joints),whose average age was 16 years(11 to 21 years).The average dose of 32P colloid was 2.1 mCi(1.0 to 3.0 mCi). Results After 6-month interval,haemarthrosis was reduced by no less than 30% in 23 patients,with a total efficacy of 88.5%.The mean frequency of haemarthrosis was reduced from 1.9 per month of presynovectomy to 0.3 per month of postsynovectomy(P