BACKGROUND:Biocompatibility is a key parameter in drug delivery systems. In general, to obtain a proper microparticle carrier, the materials themselves should have excellent biocompatibility. Besides, spherical degree and surface smoothness both have significant influence on biocompatibility.OBJECTIVE: To obtain spherical and smooth poly (lactide-co-glycolide)microparticles, so as to improve the property of biocompatibility.DESIGN: Open experiment.SETTING: Research Laboratory of Biomaterials, Jinan University.MATERIALS: The experiment was conducted in the Research Laboratory of Biomaterials, Jinan University, between June 2004 and January 2005.The materials included poly(lactide-co-glycolide), lysozyme and poly (vinyl alcohol). The other reagents were analytical pure. The instruments included a homogenizer, a mechanical stirrer, an ultrasonic cleaning instrument, a scanning electron microscope and an atomic force microscope.METHODS: ① Preparation of microparticles: Lysozyme was selected as a model protein for encapsulation into poly(lactide-co-glycolide) using a dou-ble emulsion solvent extraction/evaporation method. Three separation methods, namely direct vacuum freeze-drying, filtration and centrifugation,were investigated and compared. ② Observation under the scanning electron microscope: We observed the effect of three separation methods on the shape of microparticles. All the samples were attached to copper mounts and coated with gold, and then were observed with an electron microscope.③ Observation under the atomic force microscope: The morphological structure of the surface was analyzed with atomic force microscope.RESULTS: ① Observation results of scanning electron microscope: Compared with direct vacuum freeze-drying and filtration, centrifugation method was more efficacious in obtaining spherical and smooth microparticles based on the scanning electron microscope pictures. But results also warned us to be more careful when we prepared scanning electron microscope samples using ultrasonic to separate the aggregates. ② Atomic force microscope results indicated that the surface was smooth with the average roughness of 48.55 nm.CONCLUSION: By investigating the influence of different downstream processes, we can obtain spherical and smooth products. Besides, a new one-step method is put forward in constructing some microparticle-combined polymer based scaffolds because the combined scaffolds and microparticles are formed synchronously.

Objective To study the effect of a novel injectable scaffold material chitosan- beta-TCP combining bone marrow mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP) on repairing bone defect of goat. Methods The model of the studies was 12ram diameter circular hole tibia bone defect of goat. 30 Chinese goats were raudomly divided into 5 groups: blank group: nothing was embeded in bone defect; simple material group: the material embeded in bone defect was chitosan-beta-TCP; PRP group: the material was chitesan-beta-TCP combining PRP; MSCs group: the material was chitosan-beta-TCP combining MSCs; PRP/MSCs group:the material was chitosan-beta-TCP combining MSCs and PRP. At 4,8 weeks after operation, the samples were observed, histological and image analysis were used to evaluate the effect of bone regeneration. Results At 8 weeks, the surface of bone defect zone of PRP/MSCs group were coverd by continuous new bones, like normal bone. Histological slice showed the esteoid at boundary of normal bone of MSCs/PRP group obviously increased compare to other groups at the 4th or 8th week after operation respectively. The new bone tissues of bone defect were punctiform or lamellar new bone tissues, in which the proportion of big lamellar new bone tissue obviously increased. Image analysis showed that the areas of balnk group, simple material group, PRP group, MSCs group, PRP/MSCs group were 8.79±3.63,14.49± 3.72,24.18 ± 5.38,24.42 ± 5.10,31.10 ± 3.49 at 4 weeks and 15.41 ± 4.21,25.36 ± 5.37,30.71 ± 4.39, 33.97 ± 4.45,48.60 ± 5.97 at 8 weeks respectively. The effect of bone regeneration of PRP/MSCs group was better than other groups (P < 0.05). Conclusion The injectable tissue-engineering bone constructed with chitosan-beta-TCP, MSCs and PRP possesses good ability on repairing bone defect.

Objective To investigate the clinical effect of S-1 combined with oxaliplatin (SOX regimen) in treatment of the patients with advanced pancreatic cancer. Methods A total of 106 patients with advanced pancreatic cancer in Qingdao Fuwai Hospital from April 2015 to June 2017 were randomly divided into the treatment group (53 cases) and the control group (53 cases) according to the random number table method. Patients in the control group were treated with S-1 combined with cisplatin treatment, and patients in the treatment group were treated with SOX regimen. The cell proportion of CD3+, CD4+, CD8+and CD4+/CD8+before treatment and after 2 cycles of treatment were detected by using flow cytometry of both groups. The clinical curative effects, immunity and adverse reactions of both groups were compared by usingχ2 test and t test. Kaplan-Meier method was used to make the survival analysis. Results After two cycles of treatment, there were 4 cases of complete remission (CR), 23 cases of partial remission (PR), 17 cases of stable disease (SD), 9 cases of progression disease (PD) in the treatment group, and 0 case of CR, 18 cases of PR, 20 cases of SD, 15 cases of PD in the control group. The rate of CR+PR in the treatment group was higher than that in the control group [50.94％(27/53) vs. 33.96％(18/53)], and there was a statistical difference (χ2=5.936, P<0.05). There was a significant difference in the cell proportion of CD4+and ratio of CD4+/CD8+between the two groups before and after treatment [the treatment group: (27.31±2.48)％ vs. (37.05±2.53)％, χ2= 6.491,P< 0.01; 0.91 ±0.23 vs. 1.53 ±0.50, χ2 = 5.913, P< 0.01; the control group: (27.43 ±2.47)％ vs. (30.32 ± 2.41)％,χ2= 11.214, P<0.01; 0.90±0.22 vs. 1.22±0.34,χ2=7.992, P<0.01]. After 2 cycles of treatment, the cell proportion of CD4+and ratio of CD4+/CD8+of the treatment group were higher than those of the control group, and there were statistical differences (χ2=5.309, P<0.01;χ2= 7.112, P< 0.01). The incidence rate of side effects had no significant difference in both groups after two cycles of treatment [22.64％ (12/53) vs. 18.87％ (10/53), χ2= 1.924, P> 0.05]. The progression-free survival time in the treatment group was longer than that in the control group (P<0.05). Conclusions SOX regimen has a favorable effect on the patients with advanced pancreatic cancer. It can help to improve the immunity and prolong the survival time of the patients.

Objective To explore the risk factors of recurrence of chronic subdural hematoma (CSDH) after drilling and drainage,and to explore the cumulative risk of various risk factors in recurrence.Methods A retrospective analysis of 257 patients with CSDH,admitted to and accepted complete drainage in our hospital from January 2010 to December 2015,was performed;234 patients were without recurrence and 23 patients with recurrence.The risk factors of relapse,including age,hypertension,diabetes,hematoma characteristics,preoperative hematoma thickness,preoperative median deviation,hematoma thickness at discharge,midline deviation at discharge and hematoma density,were analyzed.Logistic regression analysis was performed to conform the independent risk factors and cumulative risk of multiple possible risk factors.Results Univariate analysis showed that age,hypertension,diabetes mellitus,preoperative hematoma thickness,preoperative median deviation,hematoma thickness at discharge,midline deviation at discharge and hematoma density were significantly different between the patients without recurrence and patients with recurrence (P＜0.05).Age,diabetes mellitus,preoperative hematoma thickness,and midline shift at discharge were independent risk factors for postoperative drilling recurrence.The cumulative effect of risk factors was that patients with two independent risk factors had a relapse risk of one 4.22-9.50-fold in patients with or without recurrence-independent risk factors,with a risk of recurrence of up to 38.0-fold in patients with three or four independent risk factors.Conclusions The risk factors of recurrence of chronic subdural hematoma after bile duct drainage are age,diabetes mellitus,preoperative hematoma thickness ≥20 mm and midline deviation ≥ 5 mm at discharge.When more independent risk factors are combined,fold increase of cumulative risk of recurrence is noted.

Objective To investigate the clinical features, treatments and prognoses of pediatric intracranial aneurysms. Methods The clinical and follow-up data of 16 consecutive patients with pediatric intracranial aneurysms (≤16 years), admitted to our hospital from January 2003 to December 2014, were analyzed retrospectively. Results Pediatric intracranial aneurysms in this study accounted for 0.78%of all intracranial aneurysms. Of the 16 children, 14 were male, 2 were female. There were 12 anterior circulation aneurysms and 5 posterior circulation aneurysms; there were 4 large aneurysms (diameter 11-25 mm) and 2 giant aneurysms (diameter≥25 mm);there were 14 complex aneurysms. At a mean follow-up duration of 16.8 months, no death was noted. Of the 12 patients received microsurgical therapy, 10 patients had favorable outcomes (modified Rankin scale [mRS] 0-1) and 2 patients had some sequelae: different degrees of disability (mRS 2-4). Of the 4 patients received endovascular therapy, 3 patients had favorable outcomes (mRS 0-1) and one patient had hemiparesis (mRS 2). Conclusions Pediatric intracranial aneurysms are different from adult intracranial aneurysms. The treatment effects and prognosis are relatively well when we select individualized treatment mode according to the clinical features of pediatric intracranial aneurysms.