To explore the mode of matrix and cell injury of articular cartilage subjected to high stress mechanical loads with a low rate of loading. Loads characterized by a constant stress rate of 0.26MPa/s to a peak stress between 2MPa and 11MPa being applied to the adult bovine articular cartilage explants was designated as the test groups. No mechanical loads were applied to the control group. All the explants were maintained in culture for the next few days after loads. The spatial patterns and severity of chondrocyte injury were determined using fluorescein diacetate and propidium iodide. Matrix damages were assessed by inspection of the microstructure of the collagen fiber network under SEM. When the peak stress was 5MPa and higher, the rate of cell death in the explants of test groups was significantly greater compared with controls, and the greater peak stress applied, the higher percentage of dead versus total cells was documented, and a more diffuse distribution of dead cells was observed. When the peak stress reached 9MPa, cell death involving full depth of the cartilage was observed in test groups . Damages to the collagen fiber network were not observed both in test and control groups. The results indicated that high stress mechanical loads with a low rate of loading resulted in more severe chonrocytes damage rather than collapse of collagen fiber network.

Animals ; Humans ; Models, Animal ; Myocytes, Cardiac ; cytology ; Stem Cells ; cytology ; Tissue Engineering

Objective To study the anti-tumor effect of 5-aza-2′-deoxycytidine(5-aza-dC) on breast carcinoma xenografted in nude mice. Methods The model of breast carcinoma xenografted in nude mice was established.Ten mice were randomized into the treatment group(treated with 5-aza-dC) and control group(treated with PBS).The mass of the tumors before and after treatment were measured in the two groups,and the inhibition rate of the tumor was calculated and the growth curve was drawn.Immunohistochemistry and Western blotting were employed to detect the expression of normal epithelial cell specific-1(NES1)gene. Results The inhibition rate of the tumor in the treatment group was 57.44%,which was significantly different from the control group(P

Animals ; Disease Models, Animal ; Facial Neoplasms ; pathology ; Magnetic Resonance Imaging ; Neoplasm Transplantation ; Rabbits

Adolescent ; Child ; Child, Preschool ; Female ; Humans ; Immunoglobulins, Intravenous ; therapeutic use ; Infant ; Infant, Newborn ; Male ; Prednisone ; therapeutic use ; Purpura, Thrombocytopenic, Idiopathic ; drug therapy

Cardiovascular Diseases ; Humans ; Induced Pluripotent Stem Cells

Objective To investigate the effects of oral glucose-electrolyte solution (GES) on resuscitation of hemorrhagic shock induced by 40% blood volume loss in rats. Methods SD rats were randomly divided into three groups; oral GES without hemorrhagic shock (GES group, n = 16) , hemorrhage shock without fluid resuscitation (HS group, n = 20) and hemorrhagic shock resuscitated with oral GES (HS + GES group, n = 20). About 40% of total blood volume was bled from carotid artery of rats to produce a model of hemorrhagic shock. GES with a volume of three times of blood loss was given three times intragastrically at 0.5, 1 and 6 hours after hemorrhage. Mean arterial pressure (MAP) was measured constantly. Blood flow in liver, kidney, stomach and small intestines, and parameters like hemato-crit, plasma osmotic pressure, alanine aminotransferase (ALT) , creatinine (Cr) and diamine oxidase (DAO) were determined 24 hours after hemorrhage. Survival rates of the rats in three groups were calculated 24 hours after hemorrhage. Results MAPs of HS + GES group were 9. 7% and 10. 9% higher than those of HS group 4 and 24 hours after hemorrhage (P < 0. 05). The blood flow of liver, stomach and small intestines in HS + GES group were 18.6% , 88.4% and 22.0% respectively, higher than those in HS group(P <0.05 or P <0.01) 24 hours after hemorrhage. The hematocrit level of HS + GES group was significantly lower than that of HS group, while the levels of ALT, Cr and DAO in HS + GES group were significantly lower than those in HS group (P <0.01). The survival rate of rats in HS + GES group was 80% , which was significantly higher than 30% in HS group (P <0.01). Conclusions Oral rehydration can significantly improve MAP and tissue perfusion, maintain blood volume and plasma osmotic pressure, alleviate organ damage and hence promote the survival rates of rats with hemorrhagic shock.

Objective:Our aim is to investigate the relationship of VEGF-C,VEGF-D and lymph node metastasis in pancreatic cancer,and to elucidate the role and significance of the cancerous peripheral lymphatic tissue.Methods: The expression of VEGF-C and VEGF-D was assayed by means of immunohistochemistry in 30 pancreatic carcinomas.Results:The positive rates of VEGF-C、VEGF-D were 73% (22/30)、57% (17/30) respectively in pancreatic cancer.The expression of VEGF-C、 VEGF-D in cancerous invasive edge was significantly higher than that in the center of cancerous tissues.There was no correlation between the expression of VEGF-C、VEGF-Dand the site,differentiation,histology types.Ⅲ~Ⅳ stages of pancreatic cancer showed strong expressions of VEGF-C、VEGF-D than that Ⅰ~Ⅱ stages of pancreatic cancer.The positive lymph node in positive VEGF-C and VEGF-D group were higher than that in the negative group.Conclusion:VEGF-C and VEGF-D induced lymphangiogenisis in pancreatic cancer,promoted the tumor cell lymph metastasis.

Objective To investigate relationships between the expression of cNOS mRNA and invasion and metastasis and prognosis in primary gastric carcinomas. Methods In situ hybridization was used to determine the expression of cNOS mRNA in 119 gastric cancer and 82 follow-up data were analyzed to obtain survival figures. Results In gastric carcinoma specimens,the expression of cNOS mRNA can be observed in the tumor cells,endothelial cells and mononuclear phagocytes;the poorer the carcinoma differentiation,the higher the positive rate of cNOS mRNA in tumor cells and endothelial cells;the expression of cNOS mRNA in tumor cells and endothelial cells reveals a significant positive correlation to the depth of invasion,lymph node metastasis and TNM stage;the patient with positive expression of cNOS mRNA in endothelial cells has a poor prognosis;the expression of cNOS mRNA in mononuclear phagocytes is not related to histopathologic type,the depth of invasion,lymph node metastasis and TNM stage.Conclusion In gastric carcinoma,the expression of cNOS mRNA in tumor cells and endothelial cells might be realted to potential of invasion,metastasis,and the patient with cNOS mRNA positive expression in endothelial cells would have a poor prognosis.

The afferant projections and their chemical nature from the midbrain raphe nuclei and periaqueductal gray to the thalamic ventral posterior nucleus were st- udied by HRP retrograde tracing combined with PAP immunocytochemical method Following injections of HRP into the thalamic ventral posterior nucleus, and reactions by HRP and PAP were performed subsequently. The double labelling cells containing HRP-positive granules and substance P-like immunoreactivity were found in various areas of brain, that is, the contralateral principal sensory nucleus of trigeminal nerve,nucleus gracilis,nucleus cuneatus, bilateral ventrola- teral divisions of the periaqueductal gray and midbrain raphe nuclei.A comparison of cell counts of double labeled cells with the total HRP-labeled cells indicated that the cells observed in the dorsal raphe nuclei were 21?7 in each rat, which constituted 48% of total HRP-labeling cells; The double labeling neurons in nuclei raphe centralis superior were found in two cases only, the cell bodies were very sparse and distributed mainly in the caudal area of these nuclei The double labeling cells were detected in bilateral ventrolateral divisions of periaqu- eductal gray, predominantly ipsilaterally. The double labeling cells observed in each rat were 26?9 ipsilaterally and 11?4 contralateraIly. The numbers of double labeling cells were 38% of the total counts of HRP-labeling cells in each side. These results above indicate that the thalamic ventral posterior nucleus receives afferent projections from midbrain raphe nuclei and ventrolateral division of periaqueductal gray and in the pathway, a part of substance P-positive neurons are exhibited. Therefore, this study provides evidence for existance ascending projection of substance P-like immunoreactivity.