筋脉通胶囊血清有效成分可预防大鼠高血糖浓度引起的施万细胞凋亡

Objective: To evaluate the effect of serum containing Jinmaitong Capsule (筋脉通胶囊, JMT) on apoptosis of Schwann cells (SCs) that are cultured in high glucose at the cellular and molecular levels. Methods: SCs were cultured in Dulbecco''s modi?ed Eagle''s medium (control group), high glucose (50 mmol/L) medium supplemented with 20% rat serum (HG group), and 50 mmol/L glucose medium supplemented with serum containing JMT (JMT group). SC apoptosis was detected using a terminal deoxynucleotidyl transferase dUTP nick end labeling kit. The expression of Bcl-2 and the caspase-3 p20 subunit in SCs were detected by real-time fluorogenic quantitative polymerase chain reaction and confocal laser scanning microscopy, respectively. Results: No apoptosis was detected in SCs that were cultured in the control group. The percentage of apoptosis of SCs cultured in the HG group was much higher than that in the control group. The apoptosis of SCs in the JMT group was lower than that in the HG group. Fluorescence intensity of Bcl-2 and the expression of Bcl-2 mRNA in SCs that were cultured in the HG group were much lower than those in the control group and much higher than those in the JMT group (P<0.01). The fluorescence intensity of caspase-3 p20 and the expression of caspase-3 p20 mRNA in SCs that were cultured in the HG group were much higher than those in the control group (P<0.01), and they were remarkably lower in the JMT group (P<0.01). Conclusions: JMT effectively prevents SC apoptosis that is induced by high glucose. This effect may be because of increased expression of Bcl-2 mRNA and protein and decreased expression of caspase-3 p20 mRNA and protein.     

Effect of Jinmaitong (筋脉通) serum on the proliferation of rat Schwann cells cultured in high glucose medium

Objective:To investigate the effect of Jinmaitong(筋脉通,JMT)serum on the proliferation of rat Schwann cells(SCs)primarily cultured in high glucose medium.Method:SOs were primarily cultured in Dulbecco's minmum essential medium(DMEM control),50 mmol/L glucose medium(50 mmol/L Glu),75 mmol/L glucose medium(75 mmol/L Glu),as well as 50 mmol/L glucose medium,with different concentrations of JMT serum(undiluted,1:2 diluted and 1:8 diluted)and Neurotropin(Ntp), respectively.The proliferation of SCs under different conditions was detected by MTT.Result:SCs grew exuberantly in DMEM within 24-72 h,but slowed down at 96 h.The proliferation of SCs was inhibited in 50 mmol/L Glu and 75 mmol/L Glu after cultures of 48,72 and 96 h,which showed that both were significantly different compared to the control group(P<0.01).The inhibition was more significant in 75 mmol/L Glu than in 50 mmol/L Glu(P<0.05).Spearman's rho analysis revealed that the proliferation of SCs had a negative correlation with the concentration of glucose(r=-0.471,P<0.01).Excluding the time factor,partial correlation showed similar results(r=-0.679,P<0.01).After 48 h,the proliferation of SCs increased significantly in JMT1:2 and Ntp compared with 50 mmol/L Glu(control 0.437±0.019,50 mmol/ L Glu 0.367±0.035,JMT1:2 0.426±0.024,Ntp 0.422±0.013;P<0.01),and there were no statistically significant differences among the JMT groups,the Ntp group and the control group(P>0.05).Conclusions: The proliferation of SCs was inhibited in high glucose medium,and the inhibition was reduced by different concentrations of JMT serum,especially at JMT1:2.     

Mechanism of thalidomide to enhance cytotoxicity of temozolomide in U251-MG glioma cells in vitro

Background Glioma is the most common primary brain tumor with poor prognosis. Temozolomide has been used with thalidomide to treat gliomas. We investigated the synergistic mechanism of these two drugs in vitro. Methods Human malignant glioma cells U251-MG were cultured and assigned to four groups with different treatments for 3 days： temozolomide group （100 μmol/L）, thalidomide group （100 μg/L）, temozolomide （100 μmol/L） plus thalidomide group （100 μg/L） and control group. MTT assay was applied to evaluate the cell viability. Cell cycle was analyzed by flow cytometry. The ultra-structural features of autophagosomes were observed with electron microscope. Acridine orange and monodansylcadaverine were adopted to label autophagosomes and flow cytometry was applied for quantification of autophagosomes. The expression of autophagy-associated protein was detected by Western blotting. Results Proliferation of tumor cell was obviously suppressed by temozolomide with thalidomide treatment than by either drug used alone （P=0.000 for each day）. The combination treatment induced cell cycle arrest at G0/G1 phase. Typical autophagic ultra-structural character was found after the combined treatment. Thalidomide promoted the autophagy induced by temozolomide. The autophagy-associated proteins - microtubule associated protein 1 light chain 3 （MAP1LC3） and Beclinl were more significantly up-regulated by the combined treatment than temozolomide used alone （MAP1LC3, P=0.000; Beclinl, P=0.004）. The expression level of phosphatase and tensin homolog deleted on chromosome ten （PTEN）, which promoted autophagy by suppressing PI3K/Akt/mTOR signaling pathway, was elevated by thalidomide （thalidomide group： P=0.000; combined group： P=0.002）. Conclusions Thalidomide enhances the cytotoxicity of temozolomide by promoting the autophagy induced by temozolomide. Contributing to the up-regulation of PTEN by thalidomide, the expression of autophagy associated protein-MAP1LC3 and Beclinl was enhanced, which leads to a reinforced autophagy in the combined treatment of temozolomide and thalidomide in vitro.     

Survival and migration of Schwann cells after the vascularized peripheral nerve grafted into spinal cord in rats

Objective：To study the survival and ability of inducing axonal regeneration of the Schwann cells after the peripheral nerve being grafted into spinal cord. Methods：A total of 30 adult female Wistar rats were randomly divided into the VN （vascularized peripheral nerve） and PN （peripheral nerve） groups. A 5-mm spinal cord defect of the left posterior column was made at the T1-3 vertebral level. The defect was grafted with the vascularized or isolated peripheral nerve respectively. The survival and proliferation of the Schwann cells were assessed by histological and morphometric analysis 8 weeks after the operation. Resuits：In the VN group, the peripheral nerve grew into the cord with lots of Schwann cells survived and proliferated, and had more NF and S-100 positive fibers than in the PN group. Conclusion：The vascularized peripheral nerve enhances the survival and proliferation of the Schwann cells and prompts the regener- ation of injured axon of the central nerve system to certain degree.     

Effect of FK506 on Expression of Hepatocyte Growth Factor in Murine Spinal Cord Following Peripheral Nerve Injury

This study is to investigate the effect of FK506 on expression of hepatocyte growth factor （HGF） in rats＇ spinal cord following peripheral nerve injury and to elucidate the mechanisms for neuroprotective property of FK506. Fifty male rats were randomly divided into normal group, injury group and treatment group. Models of peripheral nerve injury were established by bilateral transection of sciatic nerve 0.5 cm distal to piriform muscle. Then the treatment group received subcutaneous injection of FK506 （1 mg/kg） at the back of neck, while the injury group was given 0.9% saline. The L4-6 spinal cords were harvested at various time points after the surgery. Western blotting and immunofluorescent staining were used to detect the level and position of HGF in spinal cord. Immunofluorescent staining showed that HGF-positive neurons were located in anterior horn, intermediate zone and posterior horn of gray matter in normal spinal cord. Western blotting revealed that there was no significant difference in the expressions of HGF between the injury group and the normal group, while the expression of HGF was significantly higher in the treatment group than in the injury group 7 and 14 days after surgery. It is suggested that peripheral nerve injury does not result in up-regulation of the expression of HGF in spinal cord, while FK506 may induce high expression of endogenous HGF after injury thereby protecting neurons and promoting axonal outgrowth.     

Effect of glial cell line-derived neurotrophic factor on peripheral nerve regeneration in adult rat

Objective: To study the effect of glial cell line-derived neurotrophic (GDNF) on adult peripheral nerve regeneration. Methods: Transectioned sciatic nerve in adult rats was sutured into silicone channel. GDNF or SAL solution was injected into the silicone channels during operation. Four weeks later, the effect of GDNF on axonal regeneration was evaluated by degenerative neurofiber staining and HRP retrograde tracing. Results: Compared with SAL group, the percentage of degenerative neurofiber areas decreased from 17.3% to 1.9% ( P＜0.01 ) and the ratio of labeled spinal somas number was significantly increased from 43.5% to 68.3% ( P＜0.01 ) in GDNF group. Conclusion: The results suggest that exogenous GDNF can obviously enhance adult peripheral nerve regeneration.     

Expression of Beclin1 in osteosarcoma and the effects of down-regulation of autophagy on the chemotherapeutic sensitivity

To explore the expression of Beclin1 in osteosarcoma and investigate the effects of down-regulation of autophagy on the chemotherapeutic sensitivity to cisplatin （DDP）, the expression of Beclin1 in 28 specimens of osteosarcoma （group A） and 19 specimens of normal bone tissues （group B） were immunohistochemically detected. The expression of Beclin1 mRNA in MG63 cells treated with different concentrations of DDP was examined with RT-PCR. After down-regulation of autophagy in MG63 cells by an autophagy inhibitor, 3-methyladenine （3-MA）, the cell proliferation inhibition rate of MG63 cells treated with DDP was evaluated by using the MTT assay. The positive rates of Beclin1 were 67.85% in group A and 94.73% in group B. Its expression was lower in osteosarcoma than in normal bone tissues, with a significant difference found between them （P〈0.05）. RT-PCR showed that the expression of Beclin1 mRNA in the cells treated with high-dose DDP were higher than that in the non-treated cells, and no significant difference in the expression of Beclin1 mRNA was found between the cells treated with low-dose DDP and the non-treated cells. There was a positive correlation between the level of Beclin1 mRNA expression and the concentration of DDP. MTT assay showed that the proliferation inhibition rates of the cell treated with 3-MA and DDP combined were substantially increased when compared with those treated with DDP alone （P〈0.01）. This study demonstrated that autophagy may be implicated in the carcinogenesis of osteosarcoma, and DDP may induce autophagy in the MG63 cells. It also suggests that the down-regulated autophagy could increase chemotherapeutic sensitivity of DDP to osteosarcoma.     

Effects of Jinmaitong Capsule (筋脉通胶囊) on Ciliary Neurotrophic Factor in Sciatic Nerves of Diabetes Mellitus Rats

Objective:To study the effects of the Chinese medicine Jinmaitong Capsule(筋脉通胶囊,JMT) on the pathomorphology of sciatic nerves,ciliary neurotrophic factor(CNTF),and the mRNA expressions of CNTF in rats with streptozotocin-induced diabetes mellitus(STZ-DM).Methods:The animal model was established by one time intraperitoneal injection of streptozotocin.The rats were simply divided by random into 5 groups including model group,low-dose JMT group(JL),medium-dose JMT group(JM),high-dose JMT group(JH) and neurotropin group.For each of the above 5 groups,a group of 10 normal Wistar rats matched in body weight,age and gender were set as normal group.Intragastric administrations were started after the animal model established.The JL group were administered with five times the JMT dose recommended for a human adult;the JM group were administered with ten times the JMT dose recommended for a human adult;the JH group were administered with twenty times the JMT dose recommended for a human adult.The neurotropin group was administered with ten times the neurotropin dose recommended for a human adult.All rats were given intragastric administration for 16 weeks and then killed.In the 4th,8th,12th,16th week,body weight and blood glucose level were detected before and after the intervention.The morphologic changes of the sciatic nerves were observed by optical microscope and transmission electron microscope.The CNTFmRNA expressions were detected by real-time fluorescent quantitative polymerase chain protein,and the CNTF protein expressions were detected by immunohistochemical method.Results:The blood glucose levels of the STZ-DM rats were much higher than normal group(P<0.01),and there was no apparent difference between any treatment groups and the model group(P>0.05).Before and after the intervention in the 4th, 8th,12th,16th week,there were no significant differences in the body weight among all the groups(P>0.05). The sciatic nerves of STZ-DM rats might have pathomorphological changes in axons,myelin sheaths,and interstitium.The levels of CNTF and CNTF-mRNA expressions in the STZ-DM rats were both significantly decreased(P<0.01).The sciatic nerves of STZ-DM rats might have pathomorphological changes in axons, myelin sheaths,and interstitium.Conclusion:JMT could improve the pathomorphology of sciatic nerves by increasing CNTF’s and CNTF-mRNA expressions in sciatic nerve tissues,and promote the repair and regeneration of damaged nerve fibers.     

COA:Biomechanical properties of peripheral nerve after acellular treatment

Background Peripheral nerve injury causes a high rate of disability and a huge economic burden, and is currently one of the serious health problems in the world. The use of nerve grafts plays a vital role in repairing nerve defects. Acellular nerve grafts have been widely used in many experimental models as a peripheral nerve substitute. The purpose of this study was to test the biomechanical properties of acellular nerve grafts. Methods Thirty-four fresh sciatic nerves were obtained from 17 adult male Wistar rats (age 3 months) and randomly assigned to 3 groups： Normal control group, nerve segments underwent no treatment and were put in phosphate buffered saline (pH 7.4) and stored at 4°C until further use; Physical method group, nerve segments were frozen at -196oC and then thawed at 37oC; and Chemical method group, nerve segments were chemically extracted with the detergents Triton X-200, sulfobetaine-10 (SB-10) and sulfobetaine-16 (SB-16). After the acellularization process was completed, the structural changes of in the sciatic nerves in each group were observed by hematoxylin-eosin staining and field emission scanning electron microscopy, then biomechanical properties were tested using a mechanical apparatus (Endura TEC ELF 3200), Results Hematoxylin-eosin staining and field emission scanning electron microscopy demonstrated that the effects of acellularization、 demyelination, and integrity of nerve fiber tube of the chemical method were better than that of the physical method. Biomechanical testing showed that peripheral nerve grafts treated with the chemical method resulted in some decreased biomechanical properties (ultimate load, ultimate stress, ultimate strain, and mechanical work to fracture) compared with normal control nerves, but the differences were not statistically significant (P > 0.05). Conclusion Nerve treated with the chemical method may be more appropriate for use in implantation than nerve treated with the physical method.     

PRIMARY STUDY OF REPAIRING PERIPHERAL NERVE GAP WITH PORCINE SMALL INTESTINAL SUBMUCOSA

Objective To investigate the role of porcine small intestinal submucosa （SIS） conduit in axonal regeneration of rat sciatic nerve with a 10 mm gap. Methods Forty-eight rats were randomly divided into three groups （n=16）. Following a 10 mm gap was made in one side of the sciatic nerve of each rat; previously prepared SIS and auto-nerve graft were interposed into the gap to reconnect the proximal and distal ends of the nerve, respectively. In the control group, the nerve gap remained unconnected. The samples of the SIS, graft, and distal nerve in group 1 and group 2 were harvested at 6 weeks and 10 weeks after operation, respectively. Axonal regeneration was evaluated by histology, electrophysiology, and quantitated by using computer-analyzed image.Results Regenerative nerve fibers were evident which contained much myelinated axons and grew over the gap in the SIS conduits at 10 weeks. Electrophysiological examination and computer-analyzed image showed that axonal regeneration in the SIS group was similar to that in the auto-nerve grafting group at 10 weeks. Conclusion SIS as a conduit possesses the ability for axonal regeneration of the peripheral nerve, thereby having a potential to be an alternative bio-material instead of the autograft to repair the peripheral nerve gap.     

Effects of Dachengqi Decoction(大承气汤) on Morphological Changes in Enteric Nerve System of Rats with Multiple Organ Dysfunction Syndrome

Objective:To observe the morphological changes in enteric nerve system(ENS)of rats with multiple organ dysfunction syndrome(MODS)treated by Dachengqi Decoction(大承气汤,DCQD).Methods:Fifty Wistar rats were randomly assigned to the control group,MODS model group and DCQD treated group.The rats in MODS model group and DCQD treated group were injected Escherichia coli(E.coli)suspension into abdominal cavity under sterile condition.The DCQD treated group was gavaged with DCQD 2 days before the E.coli suspension was injected.Twenty-four hours after injection,the proximal segment of intestine was resected and studied by immunohistofluorescence using vesicular acetylcholine transporter,vasoactive intestinal polypeptide(VIP),substance P(SP)and neuronal nitric oxide synthase(nNOS)antibodies.The whole-mount preparations were observed by laser scanning confocal microscope to detect the changes of quantity and fluorescence integral optical density(IOD)value of intestine enteric nerves.Results:Compared with the control group,the quantity and IOD value of acetylcholine(ACh),VIP,SP and nitric oxide(NO)nerves of intestine in the MODS group were significantly decreased(P0.01),and the network of enteric nerves was remarkably disrupted.Compared with the MODS group,the quantity and fluorescence IOD value of ACh,VIP,SP and NO nerves in the DCQD group were significantly increased(P0.01),and the network of enteric nerves was remarkably recovered.Conclusions:DCQD can protect and repair damage in the network of ACh,SP,NO and VIP nerves in rats with MODS,which may be one of mechanisms involved in promoting gastrointestinal motility by DCQD.     

Effects of red orpiment on cell morphology and expression of PML mRNA and protein in NB4 and HL-60 cells

Objective To investigate the effects of red orpiment on cell morphology,expression of promyelocytic leukemia(PML)mRNA and its protein localization in NB4 and HL-60 cell lines.Methods Cell morphology was assayed by Wright’s staining and fluorescence staining,while PML mRNA expression was determined by RT-PCR.PML protein localization by evaluated by immunofluorescence staining.Results The typical apoptosis was found in NB4 and HL-60 cells treatment with red orpiment.The furion protein was no longer observed in NB4 cells,PML protein was relocated,and then degraded.In HL-60 cells,PML protein underwent a similar progress.The expression of promyelocytic leukemia(PML) mRNA was not changed in the treated cells.Concluslon Red orpiment inhibits the proliferation of leukemia cells by inducing them to undergo apoptosis.     

Myocardial autophagy variation during acute myocardial infarction in rats: the effects of carvedilol

Background The loss of cardiac myocytes is one of the mechanisms involved in acute myocardial infarction （AMI）-related heart failure. Autophagy is a common biological process in eukaryote cells. The relationship between cardiac myocyte loss and autophagy after AMI is still unclear. Carvedilol, a non-selective α1-and β-receptor blocker, also suppresses cardiac myocyte necrosis and apoptosis induced by ischemia. However, the association between the therapeutic effects of carvedilol and autophagy is still not well understood. The aim of the present study was to establish a rat model of AMI and observe changes in autophagy in different zones of the myocardium and the effects of carvedilol on autophagy in AMI rats. Methods The animals were randomly assigned to a sham group, an AMI group, a chloroquine intervention group and a carvedilol group. The AMI rat model was established by ligating the left anterior descending coronary artery. The hearts were harvested at 40 minutes, 2 hours, 24 hours and 2 weeks after ligation in the AMI group, at 40 minutes in the chloroquine intervention group and at 2 weeks in other groups. Presence of autophagic vacuoles （AV） in the myocytes was observed by electron microscopy. The expression of autophagy-, anti-apoptotic- and apoptotic-related proteins, MAPLC-3, Beclin-1, Bcl-xl and Bax, were detected by immunohistochemical staining and Western blotting. Results AVs were not observed in necrotic regions of the myocardium 40 minutes after ligation of the coronary artery. A large number of AVs were found in the region bordering the infarction. Compared with the infarction region and the normal region, the formation of AV was significantly increased in the region bordering the infarction （P 〈0.05）. The expression of autophagy- and anti-apoptotic-related proteins was significantly increased in the region bordering the infarction. Meanwhile, the expression of apoptotic-related proteins was significantly increased in the infarction region. In the chloroquine intervention group, a large number of initiated AVs （AVis） were found in the necrotic myocardial region. At 2 weeks after AMI, AVs were frequently observed in myocardial cells in the AMI group, the carvedilol group and the sham group, and the number of AVs was significantly increased in the carvedilol group compared with both the AMI group and the sham group （P 〈0.05）. The expression of autophagy- and anti-apoptotic-related proteins was significantly increased in the carvedilol group compared with that in the AMI group, and the positive expression located in the infarction region and the region bordering the infarction. Conclusions AMI induces the formation of AV in the myocardium. The expression of anti-apoptosis-related proteins increases in response to upregulation of autophagy. Carvedilol increases the formation of AVs and upregulates autophagy and anti-apoptosis of the cardiac myocytes after AMI.     

Electrical stimulation of deep peroneal nerve mimicking acupuncture inhibits the pressor response via capsaicin-insensitive afferents in anesthetized rats

Objective:To assess the inhibitory modulation of blood pressure by stimulation of the deep peroneal nerve(DPN) and to determine the involvement of nociceptive fibers in the modulation.Methods:All the animals were divided into six groups(A-F).The rats in groups A and B received no pretreatment.The rats in groups C and D received subcutaneous injection of capsaicin or control vehicle,respectively,near the DPN for 2 days.Those in groups E and F had the DPN exposed to capsaicin or control vehicle,respectively,for 20 min.Subsequently,pressor responses were induced by stimulation of paraventricular nucleus(PVN) either electrically(groups A and C-F) or chemically via injection of glutamate(group B).After two stable pressor responses(baseline),all groups were subject to 5-min DPN stimulation followed by PVN stimulation for 10 s. Arterial blood pressure,heart rate,and electrocardiogram were recorded.The pressor response was calculated as the difference in the mean arterial pressure(MAP) before and after PVN stimulation,and changes from baseline in pressor response after DPN stimulation were compared between the groups.Results:Increases of MAP of 22.88±2.18 mm Hg and 20.32±5.25 mm Hg were induced by electrical(group A) or chemical(group B) stimulation of the PVN,respectively.These pressor responses were inhibited by stimulation of the DPN,and the MAP was reduced to 12.00±2.10 mm Hg in group A(n=6,P<0.01) and 7.00±2.85 mm Hg in group B(n=6,P<0.01). Subcutaneous injection of capsaicin(125 mg/kg) near the DPN in group C(n=7) had no effect on the inhibitory effect of DPN stimulation compared with the group D(n=9),and neither did blockade of nociceptive fibers with capsaicin in group E(n=6) compared with group F(n=8).Conclusion:Stimulation of the DPN mimicking acupuncture has an inhibitory effect on the pressor response,and the effect is mediated by capsaicin-insensitive afferent fibers in the DPN.     

Comparative analysis of CT and pathological findings of peripheral nerve sheath tumors

Objective: To improve the qualitative diagnosis of peripheral nerve sheath tumors by computed tomography(CT). Methods: CT findings of 64 cases of pathologically confirmed nerve sheath tumors were compared with the pathological findings of the tumors. Results: Low density of the tumors shown in plain CT images was related to dominating reticular structure in the tumor as found pathologically. Tumors with intact capsule found by pathological findings were shown with smooth margin in CT images. Inhomogencous density and enhancement of the tumors in CT images was related to tumor necrosis, liquefaction and cystic degeneration, and inhomogeneous enhancement also involved the retieular structure. Conclusion: Nerve sheath tumors are characterized by distribution along the nerves, lower density than that of muscles in plain CT images, and inhomogeneous enhancement in enhanced CT, which can help differentiate nerve sheath tumors from other soft tissue tumors. When nerve sheath tumors lack distinctive CT features, the diagnoses have to depend on their pathological findings.     

Sixty-one patients with diabetic peripheral neuropathy treated by Tongluo Yangyin Recipe (通络养阴方)

Objective:To observe the therapeutic effect of Tongluo Yangyin Recipe (通络养阴方,TLYYR) in patients with diabetic peripheral neuropathy (DPN).Methods:Ninety-nine patients with diabetes mellitus type 2 were assigned,according to the order of their visit,to two groups:61 in the treated group and 38 in the control group.They were given the same information about diabetes mellitus and treated with the same therapy:strict diet control and Western drugs for hypoglycemia.In addition,the treated group received one dose (200 mL) of TLYYR in water decoction every day in two portions,while the control group had vitamin B_1 100 mg and vitamin B_(12) 250μg administered daily via intramuscular injection.The course for all patients was 28 days.Results:The treated group experienced a therapeutic effect superior to that of the control group,with the difference between the total effective rates and the markedly effective rates (P<0.05,P<0.01).The blood levels of total cholesterol (TC) and triglyceride (TG) fell,the hemorrheological manner improved,the transmission velocity of the median nerve and common peroneal nerve significantly increased in the treated group after treatment (P<0.05), although the treatment showed no significant influence on blood glucose level (P>0.05).Conclusion: TLYYR could promote blood microcirculation,improve nutritional metabolism of peripheral nerve,and thus accelerating DPN repair.     

Effects of Calcium Dobesilate on Glomerulus TIMP1 and Collagen Ⅳ of Diabetic Rats

Summary ： To observe the effects of calcium dobesilate on the expression of glomerular tissue inhibitor of metalloproteinase 1 （TIMP1）, collagen Ⅳ , and ultrastrueture of glomerular basement mem- brane in diabetic rats, rats model of diabetes was established by unilateral nephreetomy and intraperitoneal injection of 1% STZ （55 mg/kg）, and rats were administered calcium dobesilate 100 mg/ kg （DD group） or distilled water （DM group） respectively. 12 weeks later, the changes in the renal uhrastrueture and ereatinine clearance rate （Cer） were examined in each group. The expression of glomerular TIMP1 and collagen Ⅳ were studied by immunohistoehemieal staining. Our results showed that after 12 weeks, the Cer in DD group increased and was significantly higher than that in DM group. Electron microscopy showed that thickness of glomerular capillary basement membrane （GBM） in Group DD was less than that of DM group. No hyperplasia of collagen fibers was found, and the distance betweeh the holes of endothelial cells in DD group was not as even as that in the normal group, but more even than that of DM group, and podocyte processes was still in order. Immunohistochemical staining of glomeruli showed that expression of TIMP1 and collagen Ⅳ in DD group were significantly less than those of DM group DM. It is concluded that calcium dobesilate can improve diabetic nephropathy by inhibiting the overaccumulation of collagen Ⅳ and calcium dobesilate may also contribute to diabetes by inhibiting the expression of TIMP1.     

In vitro toxicologic study of chitin short fiber reinforced polycaprolactone composite

To investigate the cytotoxicity and cytocompatibility of chitin fiber reinforced polycaprolactone composite in vitro in order to provide useful scientific basis for clinical application. Methods: Cell morphology, observation,MTF and DNA assay were used to evaluate the influence of the composite on the morphology, growth and proliferation of cultured L-929 cells. Results: The composite did not impair the morphology of cultured cells in vitro. MTF and DNA assay demonstrated that the growth and proliferation of the cultured cells were not significantly inhibited by the composite. Conclusion: The composites have fine cytocompatibility and are safe for clinical use of reconstruction of chest wall defects.