Objective To investigate the possibility of creation of tissue engineered heart valve leaflets in vitro . Methods Aorta were obtained from 9 hybrid young pigs. The endothelial cell, fibroblast and smooth muscle cells were isolated and cultured to get enough cell. The expanded fibroblast, smooth muscle cell,and endothelial cells were seeded on the polymers sequentially. The cell polymer constructs were sent for scanning electron microscopy(SEM) examination after cultured for 7, 14, and 28 days. Histological examination were performed after the cell polymer constructs cultured for 28 days. Results SEM showed that the number of cells on the polymers increased as the culture time prolonged, with the formation of matrix. After 28 days, there were a great number of cells and large amount of matrix on the scaffolds. The confluent cell had covered a large area of the polymers. Hematoxylin and eosin(HE) stain showed large amount of cells attached to the polymers. Conclusion With the viability of the cultured cellular scaffolds,it is possible to create tissue engineered heart valve leaflets in vitro.
To observe the collagen-hydroxylaptite composite in the repair of bone defect, ten minipigs were chosen to make a mandibular dafect measuring 2 cm in diameter and the composite was implanted, while the use of autogenous bone graft and the blank wese served as control. On the 4, 8, 12, 24 and 48 weeks after the operation, the animals were sacrificed and the samples were examined under light microscope. The result showed that: no infection or necrosis occurred. The composite coalesced with host bone and the outcome was similar to that of the autogenous bone graft. No foreign body giant cells or vacuum left from osteonecrosis was observed. It was suggested that the composite had the advantage of abundant supply, easy to handle and no harm. The biocompatibility was good and might be hopeful as a bone substitute.
Histological studies and morphometry quantitative analysis have been performed on trial rabbit’s dilated common bile duct(CBD),which does not dilate simultaneously.The results shows:①Epithelia of rabbit’s CBD have a ber reparable function,which is fairly significant to the prevention of bile duct’s further injure under the pathogenic situation.②The smooth muscle cell(SMC)of the CBD is the histological basis of contraction,some SMC can be seen in contracting state under light microscope.This indicates that the SMC in rabbit’s CBD possess contracting function.③The collagenous and elastic fibers have the normal histological morphometric characteristics and quantity in it’s dilatation process,and no breekdown and degeneration of the fibers can be detected.Because of the morphological structure of these sections is quite similiar with normal ones,theoretically,we suspect that when pathological change of bile duct’s distal portion is relieved and the bile pressure is normal again.It is possible for this dilating bile duct to return to its formal shape and size.
Objective To observe the characteristics of morphosis parameter of the optic disc of physiologic large cup. Methods 100 eyes with physiologic large cup and 74 eyes with normal cup were examined by Heidelberg Retina Tomograph (HRT ). The differences of morphosis parameters between two groups were analyzed comparatively on disc area (DA), cup volume (CV), cup/disc area ratio (C/DR), rim area (RA), cup volume (CV), rim volume (RV), mean cup depth (MeCD), maximum cup depth (MxCD), cup shape measure (CSM), height variation contour (HVC), mean retinal nerve fiber layer thickness (mRNFLt), and retinal nerve fiber layer cross-section area (RNFLcsa). The characteristics of the inferior, superior, nasal, and temporal quadrants of the physiologic large cups were analyzed. Results DA, CA, C/DR, CV, MeCD, CSM （P=0.00, respectively）and MxCD （P=0.04）were significantly larger in eyes with physiologic large cup than in eyes with normal cup. RA, RV, HVC, mRNFLt, RNFLcsa （P=0.00, respectively) were significantly smaller in eyes with physiologic large cup than in eyes with normal cup. The temporal quadrant of RV of the physiologic large cup is the narrowest. RNFLcsa decreased as the fol lowing order: superior, inferior, nasal, and temporal（P＜0.05）. Conclusions Mo rphosis parameter of the optic discs of physiologic large cup has its own repres entation on characteristics. Compared to normal cups, physiologic large cups had larger discs but smaller mRNFLt. The nasal quadrant of DA was larger than the i nferior quadrant. （Chin J Ocul Fundus Dis，2008，24：213-216）
The classification of thymoma has always been controversial topil in recent years. It hasn’t been unified because of the morphological diversity of thymoma, the heterogeneity of tumour cells and the lack of simple and effective observation index. With the development of diagnostic technique and oncobiology research, several classification methods have been drawn off, including its World Health Organization(WHO) lassification. We reviewed the main classification and discussed the problems of each classification method and their clinical guiding significamce, summarized the development tendency, methods assist the classification and clinical research of thymoma.
Objective To investigate the effect of repeated freezing and thawing combining nuclease treatment on the decellularization of bovine tendons, and the morphology, structure, biochemical compositions, and mechanical properties of the decellularized tendons. Methods A total of 48 fresh 1-day-old bovine Achilles tendons were randomly divided into 3 groups (n=16): fresh normal tendons (group A), repeated freezing and thawing for 5 times (liquid nitrogen refrigeration/37℃ thawing, group B), and repeated freezing and thawing combining nuclease processing for 24 hours (group C). In each group, 2 tendons were used for scanning electron microscope (SEM), 3 tendons for histological and immunohistochemical observations, 3 tendons for DNA content detection, and 8 tendons for biomechanical testing. Results SEM observation indicated the intact, aligned, and densely packed collagen fibers with no disruption in groups A and B, and the slightly loose collagen fibers with little disruption in group C. The alcian blue staining, sirius red staining, and immunohistochemical staining showed that the most of glycosaminoglycan, collagen type I, collagen type III, and fibronectin in group C were retained after decellularization treatment. HE and DAPI staining showed that the cell nuclei between the collagen fibers were clearly visible in groups A and B; however, the cell nuclei between collagen fibers almost were invisible with a few residual nuclei on the endotendineum in group C. DNA quantitative detection confirmed that DNA content in group C [(0.05 ± 0.02) μg/mg] was significantly lower than those in group A [(0.24 ± 0.12) μg/mg] and group B [(0.16 ± 0.07) μg/mg] (P lt; 0.05). Biomechanical testing showed that the values of tensile strength, failure strain, stiffness, and elastic modulus were different among 3 groups, but no significant difference was found (P gt; 0.05). Conclusion Repeated freezing and thawing combining nuclease processing can effectively remove the component of cells, and simultaneously retain the original collagen fibrous structure, morphology, most of the extracellular matrix compositions, and mechanical properties of the bovine tendons.
Objective Currently, there are few researches on lordosis associated with scol iosis. To explore the effects of nickel-titanium memory alloy staple (Staple) on the growth of thoracic lordosis by observing the histological changes of cartilage cells in the osteoepiphysis of the thoracic vertebrates in goats. Methods Eighteen 2-3 months old female goats, weighing 8-12 kg, were randomly divided into long staple group (n=6), short staple group (n=6), and blank control group (n=6). Long staple (7 mm) and short staple (4 mm) were implanted into T6-11 segments of goats in long and short staplegroups by anterior approach, respectively. The blank control group was not treated. The X-ray examination was performedpre-operatively and at 3 months post-operatively to observe the changes of Cobb angle. Then the growth plates and inferior facet processes of the apex vertebral body were harvested to observe the histological grades of cartilage by HE staining, and to observe prol iferation and apoptosis of chondrocytes through immunohistochemistry double label ing staining with poly-ADPribose- polymerase-p85 and prol iferating cell nuclear antigen. Results At 3 months after operation, the T6-11 Cobb angles were significantly higher than those of pre-operation in short staple group and long staple group, which were significantly higher than those in blank control group (P lt; 0.05), but there was no significant difference between short staple group and long staple group (P gt; 0.05). The results of HE staining and immunohistochemistry double staining showed that the number of chondrocytes were reduced obviously with irregular columnar arrangement and increased volume ratio of surrounding extracellular matrix in prol iferative zone and hypertrophic zone of growth plate and inferior articular process in both long and short staple groups, and this tendency was more noticeable in long staple group. There were significant differences in the grades of prol iferation viabil ity of chondrocytes between 2 staple groups and blank control group (P lt; 0.05), but there was no significant difference tewteen long staple group and short staple group (P gt; 0.05). The prol iferation viabil ities of chondrocytes in growth plate and inferior articular process were significantly higher in blank control group than in 2 staple groups (P lt; 0.01), but there was no significant difference between long staple group and short staple group (P gt; 0.05). Conclusion The histological evidences prove that the Staple implantation by anterior approach can reduce prol iferation viabil ity of chondrocytes in growth plate and inferior articular process of the thoracic vertebrates in goats, which conduces the growth direction of thoracic vertebrates to kyphosis.
By using biochemical assessment technique and histological examination,a comparative study of the cutaneous tissues in 16 patients with lymphedema of the lower extremity before and after the heating and bandage therapy, and it was noted thatthe heating and bandage therapy might:(1) the content of hydroxyproline in the affected skin would be decreased; (2) the thickness of skin was decreased and the water content was reduced; (3) the microcirculation of local tissues was enhanced, and (4) the activity of the macrophages was increased. In conjunction with the criteria of clinical observation, the action mechanism of heating and bandage therapy might be as follows: (1) improve the local microcirculation and enhance the resorption of tissue fluid and the protein, and (2) increase the activity of the macrophages, and minimize the extent of fibrosis of the affected tissues.
Objective To reveal the fibrillar network in vitreous and the effect of plasmin on this network.Methods 20 vitreous gels of freshly slaughtered pigs were divided into 2 groups, the gels in first group were digested by 3 Uplasmin (3 U/ml) at 37c for 24 hours respectively, the second group received the same PBS as control. After digestion, gels were fixed in neutral buffered formalin solution. Samples from vitreous base, cortex and the central region were observed by the technique of freeze etching electron microscopy.Results In vitreous collagen fibril network was in a three-dimensional array, collagen fibril density showed marked differences, central vitreous had the sparse fibril density, the cortex denser and the basal vitreous densest. After digestion by plasmin, the collagen fibrillar network was destructed.Conclusion Collagen fibrils in vitreous present spatial arrangement regularly, plasmin can lead to destruction of the fibrillar network.(Chin J Ocul Fundus Dis，2003，19：179-181)