Objective To develop and charaterize a series of Poloxamer-and Carbopol-based in situ gel for ophthalmic use as to enhance the ability of drug to retain in eyes and delay drug release.Methods The gel was prepared using Poloxamer 407/188 and Carbopol 974P as gelling agent and viscosity enhancer,respectively.Rheological characteristics were evaluated and behaviour of drug release in vitro was investigated by modified Franz diffusion cells.Results The rheological study indicated that the gel was physically entangled polymer solutions at 20 ℃ and then converted into a network structure with secondary bonds at 35 ℃.The gel released the drug molecules slowly in 4 h.The best fit model was Higuchi matrix model(r=0.992 3).Formulations consisting of Poloxamer 188 and Carbopol 974P were proved to be able to decrease the drug release speed efficiently.The impact on elastic modulus G" of the gel caused by those two were different.Conclusion An in situ gel with suitable sol-gel transition temperature and satisfactory release pattern could be achieved by adjusting the ratio of Poloxamer 407 to Poloxamer 188.The developed formulations have the ability to prolong the ocular residence time,which suggests it may be a new durg delivery system with bright future.

There is a large gap between the number of membrane protein (MP) sequences and that of their decoded 3D structures, especially high-resolution structures, due to difficulties in crystal preparation of MPs. However, detailed knowledge of the 3D structure is required for the fundamental understanding of the function of an MP and the interactions between the protein and its inhibitors or activators. In this paper, some computational approaches that have been used to predict MP structures are discussed and compared.
Computational Biology ; methods ; Membrane Proteins ; chemistry ; genetics ; Models, Molecular ; Protein Conformation

Objective Conclusion thoracoscope surgery clinical data and correcting Ⅲ esophageal atresia(EA) and discuss the feasibility and clinical effect.Methods 24 cases confirmed the third type of esophageal atresia were retrospectively analyzed.There were 12 male and 12 female.9 cases were type Ⅲa EA and 15 cases were type Ⅲb EA.The weights were from 1.9 kg to 3.6 kg,mean weight was 2.56 kg.The age were from born to 8 days,the mean age was 2.5 days.Before operation esophageal contrast study was carried out,also ultrasonography was routinely used to evaluate heart and abdominal viscera.Results The diagnosis of third type EA was confirmed by esophageal contrast study with a blind proximal end of the esophagus and air inflation in the gut.There were 3 cases with proximal blind pouch at the 2nd vertebrate level and the other 21 cases at the 3rd to 4th vertebrate level.All the cases except one just beginning transferred to open operation because hypo-SpO2 was corrected by thoracoscopic operation.The operation time was from 110 min to 280 min,and the mean time was 120 min.The azygos vein in the former 14 cases divided and was preserved in the latter 10 cases.So the stump of the tracheoesophageal fistula (TEF) of the latter 10 cases were covered by the preserved azygos vein or plus the parietal pleura.One Ⅲa type EA could not be repaired by the radical operation and abandoned.5 cases with anastomotic leakage were cured by conserved tactics.2 cases with early TEF recurrence were initially supported by enteral nutrition by putting nasogastric jejunal tube and corrected by the 2nd stage operation.5 cases with anastomotic stricture were dilated by two times.Conclusion It is feasible to correct the Ⅲ type EA by thoracoscopic operation with good results and nice appearances.The preserved azygos vein to cover the stump of the TEF may contribute to reduce the recurrence of TEF.

Objective To investigate the effects of the rhein on the mitochondria fission and epithelial-mesenchymal transition(EMT)of breast cancer cells MDA-MB-231.Methods Human breast cancer cells were intervened with rhein,and the cells were divided into control group(0 μmol·L-1),low dose rhein group(100 μmol·L-1),and high dose rhein group(200 μmol·L-1).The proliferation activity of the cells was detected by CCK-8,and migrations was detected by Scratch-healing migration assay.The morphology and distribution of mitochondria were detected by transmission electron microscope,and the expression levels of Dynamin-related protein 1(Drp1),mitofusin2(Mfn2),E-cadherin,Vimentin proteins were detected by Western blot.Results Compared with control group,Rhein significantly reduced the protein expression of Drp1、Vimentin(P<0.05),and increased E-cadherin and Mfn2,thus down-regulating mitochondria fission,inhibiting cell proliferation and migration.High dose Rhein was better than low dose.Conclusion Rhein can inhibit the proliferation and migration of breast cancer cells by reducing the expression of Drp1,Vimentin and up-regulating Mfn2,E-cadherin proteins.

Objective: To investigate the expression characteristics of Tim-3 on natural killer (NK) cells of peripheral blood in patients with acute myeloid leukemia (AML) and its clinical significance. Methods: Peripheral blood was obtained from 39 patients with newly diagnosed AML before intervention, with peripheral blood from 28 cases of healthy volunteers collected as normal control. Using CD3, CD56 and Tim-3 as markers, expression levels of Tim-3 on the peripheral blood NK cells were detected by immune fluorescence labeling and flow cytometry. Results: The ratio of the peripheral blood CD3^-CD56⁺ NK cells in newly diagnosed AML patients (5.74±5.31) %decreased significantly, compared with the normal control (12.55±6.33) % (t=4.596, P<0.001) . Tim-3 expression on the peripheral blood NK cells in newly diagnosed AML patients (42.67±19.08) % decreased significantly, compared with the normal control group (60.99±20.69) % (t=3.781, P<0.001) . CD3^-CD56⁺NK cell ratio of peripheral blood in AML patients was significantly correlated with Chromosome karyotype (t=2.915, P<0.005) . Expression level of Tim-3 on NK cells in the peripheral blood of AML patients had significant correlation with ratio of CR and NCCN high risk group (P<0.05) . Conclusion The rate of NK cells in peripheral blood and the expression level of Tim-3 on NK cells in AML patients decreased significantly.The lower expression level of Tim-3 on NK cells correlate with prognosis of AML.