Objective To explore the effects of heat-inactivated Lactobacillus gasseri TMC0356 on liver lipid metabolism in rats with metabolic syndrome (MS) and its possible mechanism. Methods Sixty male Sprague-Dawley rats were selected. Rats were randomly divided into 5 groups, including control group, MS model group and three TMC0356 test groups (low-, medium- and high-dose groups). The rats in each group were fed with different diets for 7 days, and the liver was dissected and removed after 15 weeks. The mRNA and protein expression levels of peroxisome hyperbioactive receptor-α (PPAR-α), sterol regulatory element binding protein-1c (REBP-1c), fatty acid synthase (FAS) and carnitine lipoacyltransferase-1 (CPT-1) genes in liver were detected. Results There was no significant difference in the mRNA expression of PPAR-α, SREBP-1c or CPT-1 among the five groups (P>0.05). The mRNA expression of FAS in low-dose TMC0356 test group was lower than that in MS model group (P=0.011), medium-dose TMC0356 test group (P=0.042) and high-dose TMC0356 test group (P=0.009). There was no significant difference in the expression of FAS mRNA between other groups (P>0.05). There was no significant difference in the protein expression of PPAR-α, SREBP-1c or FAS among the five groups (P>0.05). The protein expression of CPT-1 in low-dose TMC0356 test group was higher than that in control group (P=0.033) and high-dose TMC0356 test group (P=0.043). There was no significant difference in the protein expression of CPT-1 between the other groups (P>0.05). Conclusion Heat-inactivated Lactobacillus gasseri TMC0356 may improve the symptoms of metabolic disorder in rats by suppressing appetite, improving insulin resistance, and downregulating the expression of key fat metabolism genes such as FAS and SREBP-1c.
Objective To study the mechanism of ectopic osteogenesis of nacre/Polylactic acid (N/P) artificial bone combined with allogenic osteoblasts, and to explore the possibility as a scaffold material of bone tissue engineering. Methods The allogenic- osteoblasts seeded onto N/P artificial bone were co-cultured in vivo 1 week.The N/P artificial bone with allogenic osteoblasts were implanted subcutaneously into the left back sites of the New Zealand white rabbits in the experimental group and the simple N/P artificial bone into the right ones in the control group. The complexes were harvested and examined by gross observation, histologic analysis and immunohistochemical investigation 2, 4 and 8 weeks after implantation respectively.Results In experimental group, the osteoid formed after 4 weeks, and the mature bone tissue withbone medullary cavities formed after 8 weeks; but in control group there was nonew bone formation instead of abundant fibrous tissue after 4 weeks, and more fibrous tissue after 8 weeks.Conclusion N/P artificial bone can be used as an optical scaffold material of bone tissue engineering.
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 explore the application of regional citrate anticoagulation (RCA) in continuous renal replacement therapy (CRRT) for patients with sepsis and hyperlactacidemia, and to provide a basis for the clinical application of RCA in such patients. Methods Sepsis patients who underwent RCA-CRRT at West China Hospital of Sichuan University between May 2021 and May 2023 were retrospectively included. Patients were divided into a normal lactate group (≤2.0 mmol/L) and a hyperlactacidemia group (>2.0 mmol/L) based on their initial lactate levels before CRRT, and subgroup analysis was performed on patients with moderate hyperlactacidemia (2 mmol/L<lactate level<4 mmol/L) and severe hyperlactacidemia (≥4.0 mmol/L). Propensity score matching (PSM) was used, and baseline characteristics and outcome measures of different groups of patients were compared. Results A total of 441 patients were included, with 228 in the normal lactate group and 213 in the hyperlactacidemia group. Before PSM, there were statistically significant differences in the proportion of liver failure, proportion of chronic kidney disease, mean arterial pressure, bicarbonate, total bilirubin, creatinine, activated partial thromboplastin time, international standardized ratio, procalcitonin, and interleukin-6 between the normal lactate group and the hyperlactacidemia group (P<0.05). After PSM, there were 162 patients in both the normal lactate group and the hyperlactacidemia group. There was no statistically significant difference in baseline characteristics between the two groups of patients (P>0.05). The incidence of citric acid accumulation in the normal lactate group and the hyperlactacidemia group was 13.0% and 25.9%, respectively (P<0.05). There was no statistically significant difference in the incidence of metabolic acidosis, metabolic alkalosis, hypernatremia, filter coagulation events, or in-hospital mortality between the two groups (P>0.05). Kaplan-Meier survival analysis showed that there was no statistically significant difference in the first extracorporeal circulation lifespan between the normal lactate group and the hyperlactacidemia group (P>0.05). Among 213 patients with hyperlactacidemia, 186 had moderate hyperlactacidemia and 27 had severe hyperlactacidemia. Before PSM, there were statistically significant differences in the proportion of male, proportion of diabetes, albumin level, international standardized ratio, and interleukin-6 between moderate and severe hyperlactacidemia groups (P<0.05). After PSM, there were 22 patients in both the moderate and severe hyperlactacidemia groups. There was no statistically significant difference in baseline characteristics between the two groups of patients (P>0.05). The incidence of citric acid accumulation was 18.2% and 50.0% in the moderate and severe hyperlactacidemia groups, respectively (P<0.05). There was no statistically significant difference in the incidence of metabolic acidosis, metabolic alkalosis, hypernatremia, filter coagulation events, or in-hospital mortality between the two groups (P>0.05). Kaplan-Meier survival analysis showed that there was no statistically significant difference in the first extracorporeal circulation lifespan between the moderate and severe hyperlactacidemia groups (P>0.05). Conclusion When RCA is used for CRRT anticoagulation in patients with sepsis and hyperlactacidemia, the incidence of citric acid accumulation is high (especially in patients with severe hyperlactacidemia), and should be closely monitored.
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 study the influence of in vitro force-vascularization on in vivo vascularization of porous polylactic glycolic acid copolymer(PLGA) scaffolds with internal network channels (PPSINC). Methods After the in vitro forcevascula ization of PPSINCs covered with microvessel endothelial cells (MVEC) of mice, they were divided into two groups: the force-vascularization group (group A) and the control group with only PSINCs (group B). All the PPSINCs were planted in the mesentery of 12 mice for 2 and 4 weeks, the PPSINCs were cut out, the vascular ization of PPSINCs was investigated by histology and immunohistochemistry, and the vascularization area of the histologic section of the PPSINCswas measured with the computer-assistant image analysis system. Result After the in vitro forcevascularization of PPSINCs, the MVEC of the mice sticking on the channel wall could be seen. After the scaffold was im planted into the mice for 2 weeks, the vascularization area of the histologic section of PPSINCs (VA) in group A (2 260.91±242.35 μm2) was compared with that in group B (823.64±81.29 μm2)，and the difference was sig nificant in statistics（P＜0.01).The VA for 4 weeks in group A (17 284.36 ±72.67 μm2) was compared with that in group B (17 041.14±81.51 μm2), and the difference was not significant in statistics（P＞0.05）.The area of the actin positivestaining (AA) in the histologi c section of PPSINCs for 2 weeks’ implantation in group A (565.22±60.58 μm2) was compared with that in group B (205.91±16.25 μm2), and the difference was signi ficant in statistics（P＜0.01). After the implantation for 4 weeks, the VA in group A (4 321.09±19.82 μm2) was compared with group B (4 260.28±27.17 μm2), and the difference was not significant in statistics（P＞0.05）. Conclusion The PPSINC is a good simple scaffold model of vasculariazation. The in vitro force-vascularization can increase the in vivo vascularization of PPSINCs in the early stage.
Objective To determine the ability of the polyactic acid glue (PLA-G) in preventing epidural adhesion after laminectomy. Methods Each of the 24 randomly selected rats was done laminectomyof L2 and L5. The PLA-G, which would change from liquid to solid when meets with serum, was used in the epidural site of L5 to become a half-solid membrane(the experimental group, EG). The PLA-G was not used in the same site of L2(the control group, CG) .The gross anatomical, histological, and microscopical evaluation were made 2，4，6，8，10 and 12 weeks after operation; electron microscope observation was also made on two rats 4 weeks after operation(both EG and CG). Results Obvious epidural space was observed between dura mater and scar tissue(ST), but no cells in the epidural space were observed inEG 2 weeks after operation. Corps of the red cells between dura mater and ST and proliferation of fibroblast cell(FB) were observed in CG 2 weeks after operation. Some remaining glue shiver in the epidural space with lightly increasing fibroblast and smooth dura mater were observed in EG 4 weeks after operation. However, fragile scar conglutinated with dura mater diffusely and more FB were observed in CG. From the 6th week to the 12th week, a potential interspace between scar and dura mater was observed and PLA glue was absorbed completely in EG. However, tougher scar, which was very difficult to dissect from dura mater and surrounding tissues, was observed. According to the fibroblast ultrastructure observation, bigger nucleus and more plentiful rough endoplasmic reticulum were observed in CG. Conclusion The PLA-G can effectively reduce the epidural scar and adhesion in animal experiment.
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.
摘要:目的:研究生物降解聚DL乳酸(PDLLA)自鎖式捆綁帶固定骨折的生物力學性能。方法:80只新西蘭大白兔隨機分為兩組,建立股骨干非負重骨折動物模型,應用生物降解自鎖式捆綁帶固定骨折為實驗組,鋼絲固定骨折為對照組,分別于術后1、4、8、12周行生物力學檢查進行比較。結果:捆綁帶組在術后4、8、12周均比鋼絲組的彎曲強度高,但4周、12周時Pgt;005,無統計學差異,8周時Plt;005,提示有統計學差異。離體同種固定物不同時間段抗拉強度自身比較:鋼絲固定術后4階段抗拉強度比較Pgt;005,任何兩兩比較都沒有統計學差異,抗拉強度未隨術后時間延長發生明顯下降。捆綁帶固定術后4周與術后1周比較Pgt;005,抗拉強度無明顯降低,但術后8周和術后12周時Plt;005,抗拉強度明顯下降。結論:生物降解自鎖式捆綁帶在非負重骨折治療中可發揮良好的固定作用。生物降解自鎖式捆綁帶降解時,應力傳導促進了骨折的愈合。Abstract: Objective: To study the biomechanics function of selflocking cerclage band made of biodegradable material polyDLlactic acid (PDLLA) in the fixation of fractures. Methods: Eighty rabbits were divided into two groups. Femur fracture models were made. Fractures were fixed using biodegradable selflocking cerclage band in experimental group and metal fixation material in control group. The biomechanics was analyzed and compared after 1, 4, 8 and 12 weeks respectively． Results: The bending strength of experimental group is more ber than that of control group after 4, 8 and 12 weeks, but it was not statistically significant at 4 and 12 weeks (Pgt;005). It was statistically significant at 8 weeks (Plt;005). The tensile strength of the same cerclage instrument was compared at different stage in vitro, and the result of the control group was not statistically significant at the four stage (〖WTBX〗P〖WTBZ〗gt;005). Regarding the changes of tensile strength of the cerclage instrument at different stage, the result of the experimental group was not statistically significant after 1 and 4 weeks (Pgt;005). However, the decrease of tensile strength was statistically significant after 8 and 12 weeks (Plt;005). Conculsion: Biodegradable selflocking cerclage band could be used in thetreatment of nonweightbearing fractures. The stress force conducting promotes healing of fracture when the selflocking biodegradable cerclage band degrades.
【Abstract】ObjectiveTo investigate the influence of CO2 pneumoperitoneum on intestinal mucosa permeability in rats with liver cirrhosis. MethodsFifty rats were randomly divided into following groups: control group (n=5), cirrhosis group(n=5) and pneumoperitoneum group (n=40); the pneumoperitoneum group was further divided into 8 mm Hg group(n=20) and 13 mm Hg group (n=20). Four time points were chosen, including 0.5, 2, 6, and 12 hours after the end of pneumoperitoneum. After rat models with cirrhosis were established successfully, the abdominal cavity was insufflated with CO2 and maintained under the pressures of 8 mm Hg and 13 mm Hg respectively for two hours. The portal venous blood was collected and the levels of Dlactic acid and endotoxin were measured. ResultsThe levels of endotoxin and Dlactic acid in cirrhosis group were much higher than those of control group（P＜0.05）. The levels of serum endotoxin and Dlactic acid in pneumoperitoneum group were higher than those of cirrhosis group(Plt;0.05) regardless of pressure and time point. The endotoxin level in 13 mm Hg group was higher than that of 8 mm Hg group on different time points (F=5.466, P＜0.05), but there was no difference in Dlactic acid level between both of them（F=0.415,Pgt;0.05）.ConclusionThe intestinal mucosa permeability is increased in rats with liver cirrhosis. It can be further increased under CO2 pneumoperitoneum with certain pressure and time and in a pressuredependent manner. The permeability can decrease after removal of pneumoperitoneum.