Objective To prepare a self-made compound, hemostatic jelly with polylactic acid(PLA), which has the hemostatic and absorbable effect on injured cancellous bone. Methods Two bone defects of 5 mm in diameter and 4 mm in depth were subjected on 20 health rabbits by drilling through their either outside plate of the iliac, and were filled with hemostatic jelly(group A), bone wax(group B) and blank(group C) respectively. Hemostasis were observed and recorded after 1 and 10 minutes. Five specimens were harvested at 2, 4, 8 and 12 weeks postoperatively for histological observation. Results ① Hemostatic effect: Bleeding of injured spongy bone stopped within 10 minutes after the treatment of hemostatic jelly and bone wax, but bleeding of balnk did not stop. Hemostatic jelly and bone wax adhered to bone defects firmly within 10 minutes was after the treatment. ② Absorbable effect: Hemostatic jelly and bone defects have not changed visibly in the first 2 weeks. With histological observation 4 to 8 weeks after the operation, hemastatic jelly was absorbed gradually and replaced by osteogenous tissue. It was absorbed completely after 8 to 12 weeks. Bone wax was not absorbed after 12 weeks, no new bone tissue was observed at bone wax area. The blank was replaced by connective tissue and osteogenous tissue partially after 12 weeks. Conclusion The compound hemostatic jelly manifests both hemostatic and absorbable effects on injured cancellous bone and may substitute for bone wax in clinical application.
Objective To investigate the effect of homograft of marrow mesenchymal stem cells (MSCs) seeded onto poly-L-lactic acid (PLLA)/gelatin on repair of articular cartilage defects. Methods The MSCs derived from36 Qingzilan rabbits, aging 4 to 6 months and weighed 2.5-3.5 kg were cultured in vitroand seeded onto PLLA/gelatin. The MSCs/ PLLA/gelatin composite was cultured and transplanted into full thickness defects on intercondylar fossa. Thirty-six healthy Qingzilan rabbits were made models of cartilage defects in the intercondylar fossa. These rabbits were divided into 3 groups according to the repair materials with 12 in each group: group A, MSCs and PLLA/gelatin complex(MSCs/ PLLA/gelatin); group B, only PLLA/gelatin; and group C, nothing. At 4,8 and 12 weeks after operation, the gross, histological and immunohistochemical observations were made, and grading scales were evaluated. Results At 12 weeks after transplantation, defect was repaired and the structures of the cartilage surface and normal cartilage was in integrity. The defects in group A were repaired by the hylinelike tissue and defects in groups B and C were repaired by the fibrous tissues. Immunohistochemical staining showed that cells in the zones of repaired tissues were larger in size, arranged columnedly, riched in collagen Ⅱ matrix and integrated satisfactorily with native adjacent cartilages and subchondral bones in group A at 12 weeks postoperatively. In gross score, group A(2.75±0.89) was significantly better than group B (4.88±1.25) and group C (7.38±1.18) 12 weeks afteroperation, showing significant differences (P＜0.05); in histological score, group A (3.88±1.36) was better than group B (8.38±1.06) and group C (13.13±1.96), and group B was better than group C, showing significant differences (P＜0.05). Conclusion Transplantation of mesenchymal stem cells seeded onto PLLA/gelatin is a promising way for the treatment of cartilage defects.
Objective To investigate the feasibility of fetal liver cells for liver tissue engineering, the supporting function of poly L lactic acid (PLLA) scaffold for fetal liver cells and the effects of oncostatin M (OSM), nicotinamide (NA) and dimethyl sulfoxide(DMSO) on growth and hepatic differentiation. Methods After three dimensional PLLA scaffolds having a porous structure were prepared by using NH 4HCO 3 particle, fetal liver cells obtained from E14.5 C57BL/6CrSlc murine embryos were inoculated in the scaffolds. Cells were cultured in Williams’E medium with or without OSM, NA and DMSO for 30 days. Changes in cell number, liver-specific function, and cellular morphology were observed. Results When compared with in monolayer culture, cell number and albumin secretion increased obviously in three-dimensional PLLA. Alburmin secretion increased slightly in OSM group of monolayer culture, but increased obviously in OSM groupo of PLLA culture and in OSM/NA/DMSO group of both monlayer and PLLA cultures. Conclusion The three-dimensional PLLA scaffold is a good supporting material for the cultivation of tetal liver cells. OSM, NA and DMSO remarkaly stimulated maturation of hepatic parenchymal cells in vitro in terms of morphology and liver-specific function.
Objective To fabricate a novel porous bioactivecomposite biomaterial consisting of poly lactic acid (PLA)bone matrix gelatin(BMG) by using the supercritical carbon dioxide fluid technique (SC-CO2) and to evaluate its osteoinductive activity. Methods The cortical bones selected from healthy adult donors were processed into BMG by the defatting, demineralizing, and deproteinizing processes. PLA and BMG were mixed at a volume radio of 3∶1; then, the PLA-BMG mixed material and the pure PLA material were respectively placed in the supercritical carbon dioxide reaction kettles, and were respectively added by the NaCl particles 100200 μm in diameter for theporosity of the materials so that the porous PLA-BMG composite material and the porous PLA composite material could be formed. The mouse osteoblastlike MC3T3-E1 cells were cultured in the dulbecco’s modified eagle medium (DMEM) supplemented with 10% fetal bovine serum. Then, 20 μl of the MC3T3E1 cell suspensions containing 2 ×106 cells /ml were delivered into the culturing plate (24 wells/plate) made of the different materials, which were co-cultured for 2 weeks. In the PLA-BMG group, 100 μg of the crushed PLA-BMG material was contained in each well; in the PLA group, 100 μg of the crushed PLA material was containedin each well; and in the DMEM group, only DMEM was contained, which served as the control group. There were 6 wells in each group. The quantitative analysis onthe calcification area was performed by the staining of the alizarin red S. Theco-cultured cells were harvested and lysated in 1 ml of 0.2% Nonidet P-40 by the ultrasonic lysating technique. Then, the ALP activity and the Ca content were measured according to the illuminations of the reagent kits. Results The porous PLABMG composite material showed a good homological porosity with a pore diameter of 50-150 μm and a good connectivity between the pores. The ALP activity, the Ca content, and the calcification area were significantly greater in the PLABMG group than in the PLA group and the control group (325.59±70.40 U/gprot, 3.51±1.64 mmol/gprot, 42.98±4.44% vs. 63.62±30.01 U/gprot, 1.04±0.21 mmol/gprot, 9.55±1.94%, and 2.40±1.47 U/gprot, 0.70±0.24 mmol/gprot, 0.86±0.41%; Plt;0.05). Meanwhile, there was a statistically significant difference between the PLA group and the control group in the ALP activity and the calcification area (Plt;0.05). Conclusion The porous PLABMG composite material prepared by the use of SC-CO2 has a good steoinductive activity and can be used as a promising bone biomaterial and a bone tissue engineered scaffold.
Objective To observe the therapeutic effect of poly tetrahydrofurfuryl co-lactic acid(copolymer C4) as the biodegradable vitreous substitutes on rhegmatogenous retinal detachment.Methods Vitreoretinal surgery with copolymer C4 tamponades was performed on 32 pigmented rabbits (64eyes) with rhegmatogenous retinal detachment. The rate of reattached retina and the post operative cornplications were observed.Results Three months after the operation, reattached retina was found in 96. 4%, glaucoma in 5.5%, cataract in 10.9%, and copolymer emulsion in 10.2% of all the eyes.Conclusion copolymer C4 may withstand the retinal tear effectively for 3 months, and can be a valuable vitreous substitutes. (Chin J Ocul Fundus Dis，2004，20：27-28)
Objective To explore the prognostic value of early lactate clearance rate in patients with respiratory failure.Methods 117 patients with respiratory failure and elevated blood lactate, admitted into respiratory intensive care unit( RICU) between January 2010 and December 2011, were retrospectively analyzed. Arterial lactate and arterial blood gas were measured before and 12h, 24h, 48h, and 72h after treatment. Then12h lactate clearance rate was calculated. The acute physiology and chronic health evaluation Ⅱ( APACHEⅡ) score was evaluated before and after 12h treatment. The mortality were compared between subgroups with different lactate normalization time( lt;24 h, 24 ～48 h, 48 ～72 h, and gt;72h, respectively) . The clinical data was compared between subgroups with different prognosis ( survival or non-survival ) and between subgroups with different lactate clearance rate( ≥10% as high lactate clearance rate, lt;10% as low lactate clearance rate) . Results The mortality of the patients with lactate normalization time in less 24 hours was significantly lower than that of the patients with lactate normalization time more than 72 hours ( 5. 3% vs. 89. 2% , P lt; 0. 001) . The 12 hour lactate clearance rate of the survival group was significantly higher than that of the non-survival group [ ( 43. 6 ±26. 8) % vs. ( 12. 3 ±39. 1) % , P lt;0. 01] . The mortality of the patients with high lactate clearance rate was significantly lower than that of the patients with lowlactate clearance rate( 25. 8% vs. 71. 4% , P lt;0. 01) . Conclusion Early lactate clearance rate can be used as a marker for prognosis of patients with respiratory failure.
Objective To detect the activity of lactate dehydrogenase (LDH) and LDH isoenzyme, and to explore the relation between biological behavior ofpancreatic cancer and glycolysis. MethodsConsecutive 12 cases of pancreatic ductal adenocarcinoma and 12 benign lesions such as insulinoma from October 2006 to July 2008 were collected, as well as normal pancreatic tissues. The total activity of the LDH was detected by the LDH testing kits, and the iosenzyme pattern of LDH was inspected by the France Sebia hydrasys. ResultsCompared to the normal tissue, LDH activity ofpancreatic cancer and adjacent non-cancerous tissue was significantly higher (P＜0.05). LDH iosenzyme pattern in cancer tissue was also significantly different, the percentage of LDH4 and LDH5 increased obviously, and were greater than that innormal tissue (P＜0.05). ConclusionThe alteration of LDH activity and its isoenzyme pattern are possibly related to the pathogenesis of pancreatic cancer. Inhibit the LDH activity may be a new therapeutic strategy.
Objective To investigate the effect of tissue engineering bone compounded in vitro by nanohydroxyapatite/collagen/ polylactic acid (nHAC/PLA) and recombinant human bone morphogenetic protein 2 (rhBMP-2) in repairing rabbit critical calvarial defects. Methods Forty eight New Zealand rabbits, weighting 2.0-2.5 kg, were made the models of critical cranial defects(15 mm in diameter) and divided into 4 groups randomly. Defects were repaired with autoflank bone in the positive control group; with no implant in the blank control group; with nHAC/PLA in the negative control; and with active nHAC/PLA(AnHAC/PLA) in the experimental group(the average quality of each AnHAC/PLA absorbed rhBMP-2 was 1.431 mg). The reapir results were observed through X-ray,HE dyeing and Masson’s trichrism dyeing after 8 and 16 weeks. Results The difference of bone formation was observed by X-ray block degree of skull defect area at 8 and 16 weeks. In the 8 th week and 16 th week, the radiopacities on cranial defect were 67.21%±2.06% and 86.48%±1.73% in the positive control group； 5.84%±1.92% and 9.48%±2.72% in the blank control group; 19.13%±2.51% and 35.67%±3.28% in the negative control group; and 58.84%±2.55% and 8561%±3.36% in the experimental group. There were significant differences between the negative control and the positive control group, and between the experimental group and the positive control group at 8 weeks(Plt;0.05) . There were significant differences between the negative control and blank group, and between the experiment and the blank group at 8 and 16 weeks(P＜0.05). The histology observation showed that the width of bone trabecula at 16 weeks was more than that at 8 weeks and bone defectwas full of bone tissue in positive control group. The bone defect was full of fibrous tissue at 8 and 16 weeks, and there was no new bone in the blank group. The bone defect was full of remnant material and fibrous tissue in the negative control group. The implanted area was replaced by the new bone at 8 weeks and the new bone was lamellar at 16 weeks in the experimental group; the residual material was less in defect area and there were more osteoblasts surrounding. Conclusion The nHAC/PLA is a good scaffoldmaterial of rhBMP-2 and AnHAC/PLA has agood ability in repairing bone defect. So it is hopeful to be applied in the clnical repair of large bone defect.
【摘要】 目的 分析乳酸性酸中毒发生的危险因素，警示临床工作。 方法 回顾性分析2008年5月—2010年12月收治的32例乳酸性酸中毒患者的临床资料。 结果 32例患者均合并2型糖尿病，其中老年患者27例（占84.6%）；20例有服用双胍类降糖药物史（占62.5%）；12例合并肺部疾病（占37.5%）；9例合并心脏疾病（占28.1%）；15例合并肾功能不全（占46.9%）；8例合并肝功能异常（占25.0%）。 结论 糖尿病、老年、使用双胍类药物、合并心肺疾病及肝肾功能不全都是发生乳酸性酸中毒的危险因素。在临床工作中，对高危患者需提高警惕，尽量避免危险因素叠加以减少乳酸性酸中毒的发生。【Abstract】 Objective To analyze the risk factors of lactic acidosis. Methods The clinical data of 32 patients with lactic acidosis admitted to our hospital from May 2008 to December 2010 were studied retrospectively. Results All patients had type 2 diabetes mellitus. Among them, 27 (84.6%) were older than 60, 20 (62.5%) had ingested antidiabetic drugs of biguanides, 12 (37.5%) were complicated by pulmonary diseases, 9 (28.1%) by heart diseases, 15 (46.9%) by renal dysfunction, and 8 (25.0%) by liver dysfunction. Conclusions Diabetes mellitus, old age, ingesting of biguanides, cardiopulmonary diseases, renal and hepatic dysfunction all contribute to the occurrence of lactic acidosis. During clinical work, we should try to avoid the above-mentioned risk factors.
Objective Choose polylactide-co-glycolide/hydroxyapatite (PLGA/HA) and porous phosphate calcium (PPC) as the object that we will study, compare their degradabality and choose one as a suitable scaffold for rib reconstruction. Methods All the experiments were divided into PLGA/HA group and CPC group. Degradabality experiment in exvivo: put the two scaffold which have the same size into 0.9% NaCl, keep sterile, then put the container into warm cage，get out and weigh them in 2, 4, 8, 12 and 24 weeks, compare the different speed of the two scaffold. Degradability experiment in vivo: put the two scaffold which have the same size under the skin of the rabbit, and weigh them in 2, 4, 8, 12 and 24 weeks, the tissue around the scaffold was examinzed by HE and the scaffold was examined by electron scanning microscope. Results Micro-CT and Scanning electron microscopy shows that CPC group had better structure （1101.2228±0.6184 mg/ccm vs. 1072.5523±0.7442 mg/ccm）and porosity（70.26％±0.45％ vs.72.82％±0.51％）than PLGA/HA group; The result of degradabality experiment in vitro shows that the speed of the two scaffolds was slow. It is at 24 weeks that the degradability is obvious,and the PLGA/HA group degraded a lot which was 60%. The result of degradabality experiment in vivo shows that the speed of degradabality of PLGA/HA group was faster than that is in the 0.9% Nacl, also was faster than that of CPC group which was 96%.The reponse of tissue around the PLGA/HA was more sever than that of CPC group which is in favour of the growth of cells. Conclusion As for the reconstruction of large defect of rib, CPC is more suitable than PLGA/HA.