BACKGROUND:Water-soluble 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide(EDC) and N-hydroxysuccinimide(NHS) are non-toxic and good biocompatible crosslinking agents which can trigger collagen to crosslink and form amide bond.OBJECTIVE:To analysis the influence of crosslinking on the biological and physical properties of collagen.DESIGN,TIME AND SETTING:A crosslinking experiment of collagen was performed at the Laboratory in Department of Materials Science and Engineering of Fujian University of Technology from September to November 2008.MATERIALS:Ⅰ-type bovine collagen solution was provided by Guangzhou Chuang'er Company.EDC and NHS,as the crosslinking agents,were provided by Shanghai Gill Biochemical Company and Shanghai Bo'ao Biological Technology Limited Company,respectively.2-(N-Morpholino) ethane sulfonic acid(MES),as a buffer,was provided by Shanghai Juyuan Biological Technology Limited Company.METHODS:Collagen solution was freezed at -80 ℃ for 12 hours in refrigerator.After vacuum freeze-drying 24 hours for complete dehydration in freeze-drying equipment,collagen matrices were obtained.The collagen matrices were immersed into different concentration of EDC.NHS was added according to EDC:NHS=4:1.The MES was as the buffer to adjust pH to 3.0.Then the solution was treated as follow:washed by deionized water,vacuum freeze-drying for complete dehydration.MAIN OUTCOME MEASURES:The microstructure,shrinkage temperature,characteristics of swelling dynamics and ability of antidegradation of collagen before and after crosslinking were analyzed.RESULTS:The studies of collagen crosslinking showed that the free -NH2 functional group of collagen molecules changed into N-H functional group after crosslinking,and the amino-link formed between collagen molecules.When the concentration of EDC reached 2 g/L,the crosslinking achieved to the greatest degree.After crosslinking,the microstructure of collagen changed from a state of disorder into the close and orderly structure,and the thermal stability and shape stability enhanced.In addition,the ability to antidegradation also significantly increased after crosslinking.CONCLUSION:Using EDC and NHS as crosslinking agents,crosslinking treatment can effectively improve the biological and physiochemical properties of collagen as bone tissue engineering material.

Based on the requirements of ideal bone tissue engineering scaffold need to meet, this paper briefly summarized bone tissue engineering scaffold from material selection, design and preparation. Many domestic and abroad experiments have confirmed that bone tissue engineering scaffold is feasible, effective and superior in repairing bone tissue defects. However, so far, the constructed bone tissue engineering scaffold is far from perfect, some areas, such as the mechanical properties, degradation of speed, structure and biological activity, are still need to be resolved. With further carrying out, the research of bone tissue engineering scaffold will have ground-breaking progress, and it will have a bright future in the clinical applications.

Objective To discuss the clinical feature, diagnosis and treatment options of adolescent endometriosis Methods The records of adolescent patients with endometriosis (11 20 years old) who were admitted to First, Second and Third Affiliated Hospital of Zhongshan University and Guangdong Provincial People's Hospital between 1990 and 2003 were retrospectively reviewed Results Forty three patients were diagnosed as endometriosis either by laparotomy or laparoscopy The chief symptoms leading to the diagnosis were palpable pelvic mass (18/43), dysmenorrhea (15/43), chronic pelvic mass (10/43) and acute pelvic pain (4/43) The majority of patients (53%) presented with the revised AFS r classification stage Ⅲ, 8 cases (19%) presented with stage Ⅰ, 3 cases (7%) with stage Ⅱand 9 cases (21%) with stage Ⅳ. Nine cases (21%) had complicated genital tract abnormalities Conservative operations, including salpingo oophorectomy ins cases, ovarian cystectomy in 31 cases and laparoscopic vaporization in 8 cases, were performed Surgeries were followed by hormonal suppression using oral contraceptives in a continuous or cyclic manner Conclusions Adolescent endometriosis may occur around 4 6 years after menarche The chief symptoms are palpable pelvic mass and dysmenorrhea The treatment of endometriosis in adolescence does not differ principally from that in adult women In the treatment of endometriosis and for the prevention of recurrence, it is recommended to give 3 6 months of oral contraceptives

Objective To observe the prevalence of anionic trypsinogen (PRSS2) gene G191R mutation in patients with acute pancreatitis (AP) and chronic pancreatitis (CP),and to investigate the effect of PRSS2 gene G191R mutation on susceptibility to pancreatitis.Methods The blood samples of 82 patients with acute pancreatitis,73 patients with chronic pancreatitis and 138 healthy subjects were collected,and genomic DNA was extracted.Nest PCR were performed to amplify PRSS2 gene and restriction fragment length polymorphism (RFLP) was followed by using Hpy188Ⅲ to distinguish the G191R mutation.DNA sequencing analysis was performed to confirm the mutation status.Results The size of nest PCR products was 436 bp.RFLP2 produced 309 bp and 127 bp fragments,which were resulted from PRSS2 gene G191R mutation (GGA →AGA).DNA sequencing analysis of the PCR products further confirmed the PRSS2 gene G191R mutation.Five of eighty-two(6.1％) patients with acute pancreatitis had PRSS2 gene G191R mutation (OR=0.682,95％ CI 0.231 ～ 2.010); one of seventy-three (1.4％) patients with chronic pancreatitis had the mutation (OR =0.145,95％ CI 0.019 ～ 1.145),and the corresponding value in healthy group was 8.7％ (12/138).The G191R mutation rate in patients with chronic pancreatitis was significantly lower than that in healthy group (x2 =0.432,P =0.035),but the G191R mutation rates were not significantly different between AP group and healthy group (x2 =0.487,P =0.485).Conclusions PRSS2 gene G191R mutation facilitates the degradation of anionic trypsin,and may reduce the incidence of chronic pancreatitis.

Objective To investigate, in vitro, the co-infection of Caco-2 cells ( epithelial cells of intestinal mucosa) with Candida albicans and Enterohemorrhagic escherichia coli ( EHEC) .Methods The ability of both species to invade the Caco-2 cells was evaluated by inverted microscopy.Damage to Caco-2 cells was evaluated by measuring lactate dehydrogenase ( LDH ) activity. C. albicans virulence gene expression ( ALS3, PLB1 and SAP4 ) was evaluated by quantitative real-time polymerase chain reaction ( qRT-PCR) .Results Compared to simple infections with C.albicans alone, a co-infection invaded Caco-2 cells more rapidly, and C.albicans tended to proliferate more easily presenting in cluster shape of distribution.In addition, the LDH activity in the co-infection group (group 3) was the highest compared to groups 1, 2, 4 and 5, (F values of 14.48, 5.48, 11.74 and 3.45 respectively;all P <0.05);There was no significant difference in LDH activity found between the secondary fungous infection group ( group 5) and the EHEC infection group (group 2) (F=2.03, P=0.54) or between the secondary bacterial infection group (group 4) and the Candida albicans infection group (group 1) (F=2.74, P=0.11).The LDH activities in groups 2 and 5 were significantly higher than that in groups 1 and 4 ( all P <0.05 ) .In addition, an up-regulation of toxicity-related genes ( PLB1 and SAP4 ) were detected.The expression of PLB1 was higher in group 3 than that in group 1 ( P=0.014 3 ) and SAP4 was higher in groups 3 and 5 than that in group 1 (P=0.027 2, P=0.001 8, respectively).Conclusions Using Caco-2 cells for an infection model, this study demonstrated that co-infecting in vitro enterocytes with C.albicans and EHEC enhanced the invasiveness and tissue damaging effects of C.albicans.

Objective To analyze the value of serum procalcitonin (PCT) in patients with community acquired pneumonia (CAP),and to evaluate the role of PCT in the therapeutic effect,severity and prognosis.Methods A retrospective analysis of data and laboratory tests of 50 patients with CAP admitted from November 15,2011 to November 15,2012 in GICU was carried out.Patients with infection of other parts of body,surgical treatment and trauma were ruled out.The level of PCT (ng/mL) before and during treatment,and the relationships between PCT and respiratory failure,mechanical ventilation,treatment results were analyzed respectively.Results According to the occurrence of sepsis,50 patients were divided into sepsis group and non-sepsis group.In the non-sepsis group,the PCT level before treatment,the highest and average PCT levels during the treatment were 0.1125 (0.078,0.269),0.1235 (0.078,0.494),and 0.1355 (0.08,0.245) respectively.Correspondingly,the PCT levels in the sepsis group were 8.92 (2.715,16.33),13.53 (6.305,25.625),and 4.26 (2.1415,8.2455),and there were statistically significant differences in three values of PCT between groups (ZIst =-4.743,PIST ＜ 0.05 ; ZMax =-5.783,PMax ＜ 0.05 ; ZMean =-5.644,PMean ＜ 0.05).According to the emergence of respiratory failure during treatment,average PCT level in the patients with respiratory failure was 1.7375 (0.224,5.092),and that in the patients without respiratory failure was 0.081 ng/mL (0.049,0.146),presenting the statistically significant difference between two groups (Z =4.472,P ＜ 0.05).In case of using mechanical ventilation (MV),the average PCT level of the patients with mechanical ventilation was 1.618 ng/mL (0.224,5.092),and that in the patients without MV was 0.086 ng/mL (0.061,0.465),producing a significant difference between the two groups (Z =-3.788,P ＜ 0.05).Grouped according to the outcome of patients,the mean value of PCT level in death group was 7.4585 ng/mL (2.392,16.25),and that in the survival group was 0.1965 ng/mL (0.885,0.618),showing statistically significant difference between two groups (Z =3.857,P ＜ 0.05).The first PCT level in the GICU within 24 h after admission was used to make the receiver operating characteristic curve (ROC),and the area under the curve (AUC) was 0.9867,cutoff point was 1.25 ng/mL.Conclusions In case of CAP,the PCT level in patients with sepsis is significantly higher than that in patients without sepsis,and PCT can distinguish sepsis from pneumonia precisely.In addition,PCT is an important biomarker to judge the severity and outcomes of CAP at early stage.

Objective:To analyse clinical signification of four kinds of autoimmune antibodies in the patients with viral hepatitis.Methods:ANA RF,anti TM and dsDNA Ab in sera of patients with viral hepatitic disease were detected by means of indirect immune fluerscence(IIF) and ELISA.Results:12 of 63 (19.1%) were only one kind of autoimmune antibody in sera of patients with hepatitis B and 12 of 40(30%) of patients with hepatitis C.There were significantly higher than those of alcoholic and drug hepatitis group(P

Background and purpose: Hepatocellular carcinoma (HCC) is a hypervascular tumor associated with a poor prognosis and lack of effective treatments. Consequently, identifying novel therapeutic strategies are urgently needed. We have previously shown that the kringle 1 domain of human hepatocyte growth factor (HGFK1) is a more effective anti-angiogenesis molecule than angiostatin. In this study, we observed the effects and mechanisms of HGFK1 gene on the HCC. Methods: A recombinant adeno-associated vires carrying the HGFK1 gene (rAAV-HGFK1) was constructed.HCC of rat was induced by McA-RH7777. rAAV-HGFK1 was used to treat the rat, median survival time and metastasis rate were observed. Results: Ten days after tumor cell inoculation, surgery were performed to confirm the tumor formation, PBS, rAAV-EGFP or rAAV-HGFK1 was injected directly into the tumor nodule followed by portal vein injection. Results from our study demonstrated that rAAV-HGFK1 treatment significantly prolonged the median survival time of the HCC bearing rats from 30 days (PBS and rAAV-EGFP groups) to 49 days (rAAV-HGFK1 group). More importantly rAAV-HGFK1 inhibited tumor growth and completely prevented liver, lung and peritoneal metastasis. In the controlled PBS and AAV-EGFP group, liver and peritoneal metastasis rate were both 100%, and lung metastasis rate was 100% and 83%, respectively. While there was no metastasis found in treatment group, with only 33% of ascites happened. This was most possibly due to the primary tumor in liver but not due to the metastasis. Moreover, at a higher magnification (1000×), it was clear that the HGFK1 protein was expressed mainly in the cytoplasma of liver cells. In parallel, IHC staining of CD31 also demonstrated a significantly lower level of microvessel density (MVD) (6.21±1.6) in the liver tumor of the AAV-HGFK1 treatment group, as compared to the two control PBS and AAV-EGFP groups (25.1±2.1 and 26.8±2.5, respectively, P<0.01). HE staining showed that AAV-HGFK1 treatment induced large areas of necrosis in the tumor tissues, while minimal areas of necrosis were observed in the tumor tissue in the control groups. In addition, no toxicity appeared when high dosage (4.8× 1012 vg/rat) of rAAV-HGFK1 was administered in rats. Conclusion: Results from this study demonstrated that HGFK1 inhibited the growth and metastasis of HCC and prolonged the survival time of animals with HCC through anti-angiogenesis effects. No obvious toxicity was observed. It might be the novel promising treatment for HCC and other cancers.

Objective To study and investigate the detection value of noninvasive cerebral hemodynamics and serum nerve func‐tion indexes in the patients with craniocerebral injury .Methods Totally 64 patients with craniocerebral injury in our hospital from September 2013 to May 2015 were selected as the observation group ,meanwhile 64 healthy persons with the same age were selected as the control group .Then the noninvasive cerebral hemodynamics and serum nerve function indexes were compared between the two groups ,furthermore the detection results in the observation group were compared among the patients with different severity de‐grees and intracranial pressures .Results The middle cerebral artery blood flow indexes of the observation group were all higher than those of the control group ,the serum nerve function indexes were also higher than those of the control group ,and the middle cerebral artery blood flow indexes and serum nerve function indexes of the observation group had obvious differences among the pa‐tients with different severity degrees and intracranial pressures too (P< 0 .05) ,showing statistical significance .Conclusion The noninvasive cerebral hemodynamics and serum nerve function indexes have highe detection value in the patients with craniocerebral injury ,and have active clinical role for the understand of disease severity degree and intracranial pressure situation .