In order to study the influence of severity of tendon injury on the morphology of collagen fibers during healing process of extensor tendons, 40 female Wistal rats were used for investigation. The rats were divided into 2 groups. Transection of the tendon of extensor digitorum longus was performed in one group, while partial section of the same tendon was performed in the other group. Morphometric analysis was undertaken on the 15th, 30th, 60th and 90th day after operation. The result was that there was no significant difference between the two groups both in distribution and diameter of collagen fibers on the 15th and 30th days (P gt; 0.05). However, there was significent difference between those on the 60th and 90th days (P lt; 0.05). It was concluded that the severity of the tendon injury could influence the morphology of collagen fibers during the late stage of tendon healing.
Objective To observe ultrastructural changes of the intervertebraldisk in the corresponding area after internal fixation of spinal column. Methods Twenty-four Japanese big ear rabbits were divided into internal fixation of spinal column group (n=12) and control group (n=12). The internal fixation model was made as follows: The spinous processes and erector spinal muscle were exposed and the T10L3 spinous processes and the relevant two-side articular processes under the periosteumwere isolated. With the help of L-shaped Kirschner wires, the steel wire was threaded through the articular of T11,T12,L1 and L2, and were connected with L-shaped Kirschner wries. After 6 months of operation, the following intervertebral disk tissues were observed with transmission electeon microscope: nucleus pulposus, internal annlus fibrosus and external anulus fibrosus of L1 intervertebraldisk. The T12and L2 intervertebal disk surface structure was observedhorizontally and longitudinally with scanning electron microscope, respectively. Results After internal fixation of spinal column, the structural changes of cells in nucleus pulposus and internal annulus fibrosus occurred earlier than that in the external annulus fibrosus. Proteoglycan and special structure were found in nucleus pulposus and matix of annulus fibrosus. However, the forms of special structure in nucleus pulposus and internal layer of annulus fibrosus were different. In the degeneration matrix of intervertebral disc, the proteoglycan particles and special structure were obviously decreased. Conclusion Abnormal stress environment can result in the degeneration of intervertebral disk. There is a regular distribution of the special structure in nucleus pulposus and matrix of annulus fibrosus, which is related to biology behaviour of proteoglycan particles in the degeneration of intervertebral disk.
The DNA content, cellular ultrastructure and the expression of blood group Y antigen and immunosuppressive acidic protein-2(IAP-2) were observed in normal breast, cystic hyperplasia of breast and breast cancer. The results showed: the results observed in the cells of cystic hyperplasia with epithelial proliferation grade Ⅰ were similar to those in normal breast cells. The DNA content increased, the hypoplasia and dedifferentiation features in some structures of cellular membrane and nucleus were observed, and the abnormal antigens expressed in part of the atypical hyperplasic cells. The DNA content and ultrastructure in a part of cells with aypical hyperplasia grade Ⅲ were similar to those in the cells of breast cancer grade Ⅰ. The results indicated that in the couse of atypical hyperplasia, the biological abnormalities and its extent of those cells were closely related to the differentiation extent, the developing tendency and the risk of canceration of the cystic hyperplasia of breast.
OBJECTIVE: To study the characteristics of, morphology histology and ultrastructure of anterior cruciate ligament(ACL) autograft and two-step cryopreserved ACL allograft after transplantation. METHODS: Sixty New Zealand rabbits and sixty Japanese rabbits were randomly divided into two groups: ACL autograft group and two-step cryopreserved ACL allograft group. Immunosuppressant were not used after transplantation. The histology and ultrastructure of the ACL of transplantation and normal knee were observed after 4 weeks and 12 weeks, respectively. RESULTS: The rate of remodeling process was faster in ACL autograft than in two-step cryopreserved ACL allograft, but there was similar remodeling process between two groups 12 weeks after transplantation. The proportions of large-diameter fibers(gt; or = 80 nm) of ACL autograft and cryopreserved ACL allograft were 6% and 24% in the 4th week, and were 0 and 2% in the 12th week, respectively. The proportions of small-diameter of fibers(lt; 80 nm) of ACL autogrft and cryopreserved ACL allograft were 94% and 76% in the 4th week, and 100% and 98% in the 12th week, respectively. Histologic incorporation in ACL autograft was similar to that in cryopreserved ACL allograft. CONCLUSION: Two-step cryopreserved bone-ACL-bone allograft were similar to bone-ACL-bone autograft cryopreserved in remodeling process and histology. The rate of remodeling process was faster in ACL autograft than in cryopreserved ACL allograft.
Objective To investigate whether the agonist of delta opoid receptor D-Ala(2),D-Leu(5) enkephalin (DADLE) has the effect of decreasing myocardial injury during ischemia-reperfusion of adult rabbits’ myocardium，so that a new mehanism and way to myocardial protection could be found. Methods Langendorff model was used during the experiment. Thirty rabbits were divided into three groups randomly (each group 10 rabbits). Control group: St.Thomas Ⅱ cardioplegic solution was used; group 1: St.Thomas Ⅱ cardioplegic solution and DADLE (1mg/kg) were used; group 2: St.Thomas Ⅱ cardioplegic solution and naloxone(3mg/kg) were used to induce the hearts to arrest respectively. After arrest the hearts were reperfused respectively. Data of left ventricle development pressure(LVDP) was recorded before and after ischemia. Biochemical indicators of myocardium, lactate dehydrogenase(LDH) were detected before and after ischemia. Some myocardial tissues were used to explore the changes of the tissue of ultrastructure with electron microscope，when the experiment was over. Still some myocardial tissues were to be detected by flow cytometer to evaluate the apoptosis of the myocardium. Results The LDH and LVDP showed significant difference among three groups after ischemia(Plt;0.05); LVDP in group 1 was higher than those in group 2 and control group(69.8±5.8 mmHg vs. 23.4±3.9 mmHg; 69.8±5.8 mmHg vs. 37.9±4.7 mmHg; Plt;0.05), the LDH in group 1 was lower than those in group 2 and control group(1 272.6±59.1 U/L vs. 2 764.4±27.7 U/L, 1 272.6±59.1 U/L vs. 1 884.4±37.5 U/L; Plt;0.05). The apoptosis rate in group 1 was lower than those in group 2 and control group. As could be shown from the ultrastructure: mitochondria structure was nearly normal in group 1; mitochondria structure was injuried severely in group 2; there was a minor injury in control group. Conclusion Agonist of δ opoid receptor DADLE in cardioplegic solution could induce hibernation, which has myocardial protection effect during ischemia-reperfusion injury.
In order to study the influence of biliary tract obstruction on enteromicroflora,we ligate the canine biliary tract to observe the acrobic and anerobic bacteria in the duodenum and ileum at intervals of post-ligation(the 10th,20th,30th days),and to study the pathogenesis and ultramicroscopic of the ileal mucosa at the same intervals.The results showed that:the population and species of enteroflora in small intestine gradually increased after biliary obstruction.Bacteria(especialy E.coli) ascended to the upper part of small intestine,from their normal habitant of lower part of small intestine.Therefore the radio of general aerobia and E.coli risen obviously in duodenum.The longer the obstruction,the more pathologic changes were observed in ileal mucosa.such as edema,leukocytes infiltration and destruction of epithelial villi.All of those changed may be the causative factor of biliary tract infection.So that,in the programs of preventing enterogenic infection at the state of biliary tract obstruction,the protection and adjusting of normal enteroflora should be adventently considered.
Objective To explore the ultrastructure characteristics of pulmonary arteries in smokers with normal lung function and with chronic obstructive pulmonary disease ( COPD) . Methods 33 patients who undertook surgery for peripheral lung cancer were collected. According to smoking history and pulmonary function, the patients were divided into three groups, ie. non-smokers with normal pulmonary function ( group A, n = 10) , smokers with normal pulmonary function ( group B, n = 13) , and smokers in stable phase of COPD ( group C, n = 10) . Normal lung tissues without cancer were sampled and observed under light and electric microscope. Results ①Compared with group A, the thickness of intimal layer of intra-acinar pulmonary muscular arteries of group B and C were significantly higher, the area of their lumenwas lower, and the proportion of their muscular arteries was higher( P lt; 0. 01) . ②Ultrastructure of small pulmonary arteries of group A showed that intimal layer was normal, so as to endothelial cells and smooth muscle cells. Collagen fiber was not increased. Ultrastructure observation of group B showed that endothelialcells were distorted, basal membrane was thick, and collagen fiber increased in vessels. Ultrastructure observation of group C showed that endothelial cells degenerated, vascular intima thickness increased, andsynthetic phenotype smooth muscle cells increased. ③ Smoking index was positively correlated with the proportion of muscular arteries and the proportion of intimal area( r =0. 464,0. 635, P lt;0. 05, respectively) ,and negatively correlated with the proportion of lumen area( r= - 0. 603, P lt;0. 05) . Conclusions Smokers with normal lung fuction and with COPD show the similar ultrastructural characterizations in endothelial cells, smooth muscle cells, and pulmonary arterial remodeling, which related closely to smoking.
In order to investigate the effect of nerve compression on neurons, the commonly used model of chronic nerve compression was produced in 48 SD rats. The rats were sacrificed in 1, 2, 3, 4, 5 and 6 months after compression, respectively. The number of neuron and ultrashruchure of alpha-motor neurons and ganglion cells of the corresponding spinal segment were examined. The results showed as following: After the sciatic nerve were crushed, the number of neuron and ultrastructure of alpha-motor neurons and ganglion cells might undergo ultrastructural changes, and even the death might occur. These changes might be aggravated as the time of crushing was prolonged and the compression force was increased. It was concluded that for nerve compression, decompression should be done as early as possible in order to avoid or minimize the ultructural changes of the neuron.
Objective To isolate，culture and expand bone marrow mesenchymal stem cells （MSCs） in vitro，induce MSCs to differentiate directionally towards chondrocytes，and provide experimental basis for clinical application of MSCs and construction of tissue engineering tracheal cartilage. Methods Cultured MSCs were isolated from bone marrow of Sprague-Dawley rats，purified using adherence separation，and identified by flow cytometry analysis. Transforming growth factor β1 （TGF-β1）and insulin-like growth factor 1 （IGF-1） were used as main induction factors to induce MSCs to differentiate directionally towards chondrocytes. The expression of collagen typeⅡwas evaluated by immunocytochemical staining 21 days after induction. Light microscope and electron microscope were used to observe tiny and ultrastructural changes of the cells before and after induction. Results The expression of collagen typeⅡwas positive by immunocytochemical staining 21 days after induction. MSCs were fusiform before induction under light microscope and electron microscope. After induction，the cells became larger，polygon，star-shaped or triangular. Transmission electron microscope showed that the cells had abundant organelles，larger nuclei and more nucleoli after induction. Conclusion Abundant organelles，larger nuclei and more nucleoli are the ultrastructure changes of chondrocytes differentiated from MSCs，indicating that the cells are active in differentiation and metabolism.
To evaluate the biological tolerance of the human liver to prolonged warm ischemia, 20 patients who underwent liver resections with hepatic inflow occlusion are reported. Biopsy of liver were performed during and after consecutive periods of hepatic ischemia, and speciments were observed under light and electron microscope. The results showed that hepatic vascular occlusion for ＜30 min, resulted in atotissular temporary but reversible pathologic and ultrastructural changes in liver, even patients with liver cirrhosis had better recovery from the operation when the hepatic ischemia was lengthen up to 40 min.
