[Objective]To prepare a cartilage acellular matrix scaffold and to explore its feasibility in cartilage tissue engineering. [Methods]Microparticles about 100 ?m~154 ?m were prepared after calf cartilage physically shattered and experienced gradient centrifugation,and then treated by a modified Courtman's four-step method which was improved to produce acellular cartilage matrix.After this treatment the microparticles were made into 3% suspension which was placed into moulds.With the freeze-drying method,3-D cartilage acellular matrix (CACM) was prepared.The scaffolds were cross-linked by a neotype crosslinking agent genepin for 48h,and then placed into glycine solution server times for removing redundant genepin.The freeze-drying method was used to prepare CACM.The scaffolds were investigated by gross observation,histological staining (haematoxylin-eosin,toluidine blue) ,scanning electron microscope (SEM) observation and porosity measurement,water absorption rate and degradation rate analysis.After being cultivated for ten days,bone marrow stranal cells (BMSCs) of rabbit were seeded into the scaffold.MTT test and SEM were done to assess the growth and proliferation of BMSCs.[Results]Gross observation showed the scaffolds had a loosely porous and dark blue appearance after being cross-linked by genepin.The histological staining (haematoxylin-eosin,toluidine blue staining) showed that there were no chondrocyte fragments in the scaffold.The CACM scaffold had 90% porosity,(1314?337) % water absorption rate,and (13.69?7.3)% or (25.99?8.9) % degradation rate at 2 or 4 weeks.MTT test showed that BMSCs grew well in the 3-D CACM scaffolds of logarithmic trend,supporting that the scaffolds had no cytotoxic effect on BMSCs.SEM micrographs indicated that the scaffolds were porous and the cells covered the scaffolds firmly with cell processes.[Conclusion]The improved Courtman's four-step method makes a more thoroughly acellular scaffold.The 3-D CACM scaffold retains most of extracelluar matrix.After being cross-linked by genepin,the 3-D CACM scaffold has good biocompatibility and degradation rate of the scaffolds is decreased,which makes it a suitable carrier for cartilage tissue engineering.

Animal Feed ; Animals ; Gynostemma ; Male ; Plant Extracts ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Swimming

Female ; Foreign Bodies ; Humans ; Middle Aged ; Nasal Cavity ; pathology ; Paranasal Sinuses ; pathology

The amount of the research-oriented graduates is increasing in affiliated hospitals of medical universities.To create an effective training model can not only help students to succeed but also contribute great to the research level of hospitals.In this study,we summarized our experience,such as individualized teaching,the unity of thinking and performing,words and deeds as well as unity of clinic and research on the formation of research ideas,attitudes and styles.Based on our experiences we hope to provide meaningful methods for the training of medical graduates.

[Objective]To compare the purity and extraction rate of four purecollagen type I products prepared from various biomaterials by a limited enzyme digestion method for the use in tissue engineering.[Method]Bovine cortical bone, bovine achilles tendon, porcine achilles tendon and porcine skin were splitted into pieces of 0.2-0.5 mm. After being immersed in glacial acetic acid, they were extracted with pepsin. Then the crude products were dissolved, centrifuged, dialyzed and freeze drying to prepare pure collagen type I. The final products were confirmed by absorbance, amino acid analysis and'SDS-PAGE electrophoresis comparing them with the products of Sigma Company.[Result]The wave length of maximum absorbance of the final products was 230 nm, and the amino acid analysis and SDS-PAGE electrophoresis confirmed that the final products were collagen type I. The purity of product extracted from bovine cortical bone was the highest (96.12%) and higher than that from Sigma Company. The extraction rate of bovine achilles tendon collagen was the highest (75.34%).[Conclusion]Collagen type I of higher purity and higher extraction rate can be prepared using a limited enzyme digestion method.And the product from bovine cortical bone is better than the others,which has a promising prospect.

[Objective]To investigate the technical advantages of micro-CT in the research of three dimensional structure of bone tissues over histological section technology. [Method]Different kinds of bone tissue related specimen were observed by micro-CT and histological section,respectively.The diversity of the sample treatments,result expressions and test data were compared.[Result]Micro-CT showed great advantages in displaying three dimensional structure characteristics of bone tissues.Both quantity and quality changes of bone tissues could be precisely determined by micro-CT which was much better than histological section technology.However,histology showed great advantages in displaying the cell figures,growth and differentiation.[Conclusion]Micro-CT provides a novel test method for both sample treatments and result expressions.Compound with histological technology,micro-CT can display the appearance and structure of bone tissues more sufficiently.

[Objective]To observe the biological properties of a novel collagen/hydroxyapatite composite scaffold in vitro and to evaluate the possibility of application being used in tissue engineering for osteochondral repair.[Method]The scaffolds were constructed of collagen I and hydroxyapatite.The pore size and interpores of the scaffold were observed by scanning electronmicroscopy(SEM).The porosity was measured by liquid displacement method.Rabbit bone marrow stromal cells(BMSCs) were isolated and amplified,then inoculated onto the scaffold.By SEM scanning,the condition of the cells adhering onto the scaffold was observed.The proliferation of the cells on the scaffolds was examined using MTT method,and the growth curve was drawn.[Result]The scaffold possessed high porosity and proper pore size.The pore diameter of the collagen layer was about 90?m,the pore diameter of the HA layer was about 120?m,and the overall porosity of the composite scaffold was 75%.The proliferation of the cells on the scaffold was good.[Conclusion]The novel collagen/hydroxyapatite composite scaffold possesses desirable pore structure and good biocompatibility,and it can be used in tissue engineering for osteochondral repair.

0.05).[Conclusion]The osteochondral scaffold of the collagenⅠ-sodium hyaluronate-fbrin glue tri-copolymer scaffold bonding with antigen-extracted bovine cancellous bone has an appropriate structure and a good biocompatibility,which makes it a useful scaffold in the osteochondral tissue engineering.

Objective To observe the clinical efficacy of naloxone plus aminophylline in the treatment of children with acute respiratory failure.Methods 72 patients with acute respiratory failure were randomly divided into the study group and the control group.36 cases in the study group were given naloxone plus aminophylline therapy, 36 cases of the control group received conventional therapy.And the clinical efficacy was compared.Results The total effective rate of the study group was 91.67%,which was significantly higher than 66.67% of the control group (χ2 =6.82,P <0.05).In the comparison of the effect of improving blood indicators,arterial blood pressure of the study group was (67.51 ±4.11)mmHg,which was significantly higher than (61.03 ±4.08)mmHg in the control group (t =2.64,P <0.05).The oxygen saturation of the study group was (93.55 ±8.05)%,which was significantly higher than (79.62 ±10.22)% of the control group (t =2.29,P <0.05).The arterial carbon dioxide partial pres-sure of the study group was (69.03 ±5.71)mmHg,which was also higher than (61.52 ±4.09)mmHg of the control group (t =2.22,P <0.05).The incidence rate of adverse reactions of study group was 2.78%,which was lower than 22.22% in the control group (χ2 =6.22,P <0.05).Conclusion Naloxone plus aminophy -lline used in children with acute respiratory failure obtain the desired therapeutic effect,not only can effectively improve blood indicators of children,and without significant adverse reactions,drug safety is high,it is worthy of promoting.

Objective The aim of this study was to investigate the feasibility and clinical value of detecting sentinel lymph node (SLN) with combined radioisotope and blue dye method in early stage cervical cancer. Methods Between March 2005 and April 2006, 50 patients with cervical cancer, who were staged Ⅰ b and Ⅱ a by International Federation of Gynecology and Obstetrics (FIGO), underwent SLN detection with preoperative lymphoscintigraphy. A dose of 148 MBq (4×10-4L) 99Tcm-sulfur colloid (SC) was injected into the uterine cervix at 3 and 9 o'clock position with lymphoscintigraphy taken at 15-60 min after injection. Intraoperative detection of "hot spot" lymph nodes was performed with a handheld gamma probe (γ-detection). During operation, 2-4 ml metend blue dye (BD-detection) was injected into the uterine cervix at the same positions. All patients underwent hysterectomy and pelvic lymphadenectomy. The spatial and pathological relationships of the SLN samples were compared between the two methods. SPSS 13.0 was used for statistical analysis. Results The detection rate of SLN with combined radioisotope and blue dye was 96.0% (48/50). γ-detection alone was 92.0% (46/50) and BD-detection alone was 70.0% (35/50, x2=4.92, P<0.05). In 37 patients lymphoseintigraphy showed the same SLN as γ-detection did, with a coincidence rate of 74.0% (37/50). The SLN with metastases were confirmed by histopathology in 11/48 (22.9%) patients. In the remaining 37 patients with SLN negative for metastasis, there was 1 case with non-SLN showing metastasis. In the 2 patients negative for SLN, 1 was positive for non-SLN metastasis. The SLN accuracy rate was therefore 97.9% (47/48), and the negative predictive value was 97.3% (36/37) with one patient false negative. About 72.3 % (115/159) of SLN were found in obturator region, 5.0% (8/ 159) in iuteriliac region, 12.0% (19/159) in external iliac chain, 6.9% (11/159) in common iliac region and 3.8% (6/159) in parametrium. The number of left-sided SLN detected was more than that of the right (x2=5.06, P=0.021 ). Conclusion Combined radioisotope and blue dye technique is a feasible and valuable tool to detect pelvic SLN in patients with early uterine cervical malignancy.