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

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.

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

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

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.

Background In the past few decades,the balance of Th1/Th2 is often used to explain the immune mechanisms of fungal infection and fungal disease.More recently,a novel subset of CD4+ effector Th cells has been found to participate in anti-fungal infection response.However,whether Th17 is involved in the immune response in fungal keratitis is unclear up to now.Objective Present study was to investigate the expression change of Th17 type cytokine and its specific transcription factor,retinoid-related orphan nuclear receptor gamma t (RORγt),in the cornea of Fusarium solani keratitis.Methods Ninety-six clean BALB/c mice were divided into Fusarium solani keratitis model group and control group by randomized digital table.Fusarium solani keratitis models were established by epikeratophakia-assisted corneal epithelial erasion and interlayerly injection of 5 μl (1 × 106 CFU/ml) Fusarium solani solution in the right eyes,and the equal volume of PBS was injected in the same way in the control group.10％ KOH wet film was used to examine the fungal hyphea and funga strain was identified by inoculation.The corneas were examined under the slit lamp microscope 1 day,3,5,7 days after modeling and the inflammatory response was scored based on the criteria of Wu and Hu.The histopathological examination of corneas was performed in the time points above.Real time fluorescence quantitative PCR was used to detect the expression levels of interleukin-17 (IL-17) mRNA and RORγt mRNA in the corneas.The expression of IL-17 protein in the corneas was detected by ELISA.The use and raise of the mice followed the Statement of Association for Research in Vision and Ophthalmology.Results The inflammatory scores were 3.2±0.8,6.6± 1.1,9.4± 1.1 and 6.8±0.8 in 1 day,3,5,7 days after modeling,showing a significant difference among them (F =89.786,P =0.010).The inflammatory scores were higher in the third and seventh day than that in the first day (P＜0.05),but they were significantly lower than that in the fifth day (P＜0.05).The infiltration of inflammatory cells showed a coincident tendency with the score.The expressing levels of IL-17 mRNA (2-ΔΔCt) in the corneas were 4.12±0.73,20.72±1.81 and 14.16±1.88 in 3,5,7 days after modeling,with statistically significant differences in comparison with those in the control group (P＜0.01),and the expression level was significantly higher in the fifth day than those in the first,third and seventh day in the model group(P＜0.01).The expression levels of IL-17 protein (ng/g) were significantly increased 1 day,3,5,7 days in the model group compared with the control group (P＜0.01).A similar change was found in the expression of RORγt mRNA to that of IL-17 mRNA.Conclusions Expressions of IL-17 and its transcription factor RORγt upregulate in the fungal keratitis and has an association with inflammatory degree,which suggests that Th17 subset may play an important role in the immune responses of fungal keratitis.