ObjectiveTo evaluate the change of extracellular matrix (ECM) in diabetic rat lungs.MethodsUsing special staining,immunohistochemical method and imaging analysis,the changes of distribution,area,integral optial density and relative contents of lung ECM in diabetic rats were studied.ResultsThe distributions of elastic fibres,collagenic fibres and reticular fibres increased and roughened.The type Ⅳ collagen strong staining was localized in alveolar septum,the basement membranes of bronchiole and capillary,and distributed in cordal,plexiform.Laminin was strong stained and found in alveolar septum,epithelial cells of alveolar,and the basement membranes of bronchiole and pulmonary vessels in cordal and linear distribution.Image analysis showed the area,integral optical density and relative contents of elastic fibres,collagenic fibres,reticular fibres,type Ⅳ collagen and laminin were larger in diabetic rat lungs than in control groups.ConclusionThese results showed that the changes of ECM in early diabetic rat lungs were abnormal.

AIM: The phagocytotic function and morphological changes of pulmonary alveolar macrophages (AM) of rat in high glucose or high glucose and high insulin conditions were studied. METHODS: AM were harvested from Wistar rats by bronchoalveolar lavage and were activated by Bacille Calmette - Guerin (BCG), interferon a - 2b (IFNa - 2b)or BCG and IFNa - 2b. The adherent rate, nitroblue retrazolium (NBT). reduction function and the concentrations of NO and TNF-a in culture rat AM were evaluated. The ultrastructure of AM was Observed by using transmission elects microscopy and scanning electron microscopy. RESULTS: In high glucose or high glucose glucose and high insulin conditions, the adherence of AM postponed(P＜ 0.01 ), NBT reduction of AM significantly decreased(P＜0.01); the volume of NO and TNF-a produced by AM after stimulation with BCG and IFNa-2b + BCG was significantly lower in high glucose groups than in the controls (P ＜ 0.01); their surface pseudopodia was reduced and shortened and the numbers of Golgi apparatus and rough endoplasmic reticulum decreased. CONCLUSIONS:The impaired phagocytotic function and ultrastructure of activated rat AM were much the same regardless of high glucose or high glucose and high insulin level in a short time. Diabetic subjects were predisposed to infection of the lung, which was frequently recurrent or even fatal.

AIM:To investigate the relationship between trace elements and oxidative stress in diabetic diaphragm. METHODS: Contents of copper(Cu), manganese(Mn), zinc(Zn), iron(Fe),cadmium(Cd),chromium(Cr),cobalt(Co),molybdenum(Mo) and lithium(Li) in the alloxan-induced diabetic rat diaphragm muscles were measured by atomic absorption spectrophotometer, and their superoxide dismutase(SOD) activities and malondiadehyde(MDA) contents were detected. RESULTS: The contents of Cu, Zn, Cr and Li were lower and the Fe and Cd were higher in diabetic rat diaphragm muscles than that of the control group, but there were no significant differences in Mn, Co and Mo, between control and diabetic group. SOD activities decreased significantly and MDA contents increased significantly in diaphragm of diabetic rats as compared with the control group.In addition,in diabetic rats diaphragm, there was a positive correlation between Zn and SOD, and negative correlation between Zn and MDA, and Cd and SOD. CONCLUSION: Changes of the contents of Cu, Zn, Fe, Cd, Cr, Li and the increase of oxidative stress in diaphragm were found in the early diabetes, and Zn, Cd play an importment role in oxidative stress of diabetic diaphragm.

AIM: The pathological changes in inducible nitric oxide synthase (iNOS) and vasoactive intestinal peptide (VIP) in diabetic rat lung were investigated.METHODS: Using immunohistochemical method and imaging analysis, the changes in iNOS and VIP were observed in normal and diabetic rat lung. RESULTS: In diabetic rats, the iNOS positive or weak positive staining was localized in epithelial cells of bronchi, epithelial cells of alveolar ducts, alveolar sacs, and arteries, but negative in endothelial cells of vein and capillary. Image analysis showed the area, the integral absorbance(IA) and relative contents of iNOS were significant lower than that of control (P

AIM: To evaluate the changes of diaphragm contractile properties and morphologic features in experimental diabetic rats. 糤THZ]METHODS: METHODS: Diaphragm contractility was assessed by twitch kinetics, maximal tetanic force (P 0) , tension-frequency relationship and fatigue index (FI) in vitro diaphragm strip preparations of 4th week diabetic Wistar rats, and compared with that of the control group. The structure of diaphragm was analysed in diabetic rats and control with Hematoxyline and eosin staining, Heidenhain staining and enzymatic histochemistry. RESULTS: The twitch (Pt), contraction time (CT), half relaxation time (RT 1/2 ) and FI decreased significantly in diabetic group as compared with the control group. There was no difference in Po between the two groups. The tension of diabetic diaphragm at frequencies of 25,50,75,100 and 125 Hz was significantly decreased compared with that of the normal rats. After diaphragm bundles were subjected to fatiguing stimulations and incubated with aminophylline at 250 mg/L for 30 minutes, the tension of diabetic diaphragm decreased remarkably at both high and low frequencies in comparison with that of the normal rats. In addition, the activity and optical density of ?-phosphoglycerol dehydrogenase in diaphragm from diabetic rats were significantly lower than that from control rats ( P

The relationship between plasma level of endogenous secretory receptor of advanced glyeation end products(esRAGE)and oxidative stress in diabetic patients with hypertension was investigated.The results showed that there was significant negative correlation between esRAGE and body mass index(BMI,r=-0.33), diastolic blood pressure(DBP,r=-O.38)and oxidative stress(all P<0.05).The levels of plasma esRAGE decreased significantly in diabetic patients with hypertension.BMI,DBP and oxidative stress may participate in determinining the esRAGE level in diabetic patients complicated with hypertension.

AIM:To evaluate the changes of lung morphologic features and oxidative stress in experimental diabetic rats. METHODS: The pulmonary structure of alloxan-induced diabetic rats were quantitatively studied with stereological methods. Changes of ultrastructure, activities of superoxide dismutase (SOD) and contents of malondialdehyde(MDA) of diabetic lung and serum were observed. RESULTS: The volume proportion of alveolar air and mean linear intercept of diabetic rats decreased remarkably in comparison with controls while the volume proportion of alveolar wall, the surface density of alveolar, the numerical density of alveolic area, the numerical density of alveolar and specific surface of alveolar increased significantly. The major change of the type II pneumocyte of diabetic rats was dilation of the rough endoplasmic reticulum (RER). The other findings in diabetic rats had included the presence of thickened alveolar epithelial, pulmonary capillary basal laminae and blood- air barrier, the volume density, the surface density, the mean profile area and the mean perimeter of RER in type Ⅱ pneumocyte of diabetic rats increased remarkably. And the specific surface of RER was significantly lower as compared with controls. SOD activity decreased and MDA content increased significantly in serum of diabetic rats as compared with the control group. SOD activity in the diabetic lung was not different from that of the control lung. However, the content of MDA obviously increased in diabetic lung. CONCLUSION: The morphologic features and oxidative stress in early diabetic rats are abnormal thus the lung should be considered as one of the “target organ”in diabetes mellitus.

AIM: The aim of this research is to study the earlier enzyme activity changes of the diaphragm in diabetic rats. METHODS: An enzyme histochemical method was used to observe the changes in the enzyme activities of dehydrogenases,hydrolases and oxidases in 4th week diabetic rat diaphragm. RESULTS: The activites of enzymes including SDH(Succinate dehydrogenase),MDH(Malate dehydrogenase), GDH(Glutamate dehydrogenase), ICDH(Isocitrate dehydrogenase), NADHD(NADH diaphorase), G-6-PD(Glucose-6-phosphate dehydrogenase), ACP(Acid phosphatase) and ANAE(Acid ?-naphtyl acid esterase) were increased in diabetic diaphragm compared with the control. LDH (Lactate dehydrogenase)and CCO(Cytochrome oxidase) activities were decreased, whereas NADPHD(NADPH diaphorase) showed no changes in diabetic rats. Eleven kinds of enzyme were analysed with image analysis.Optical density (A) of SDH, MDH, GDH, ICDH, NADHD, G-6-PD, ACP and ANAE in diaphragm of diabetic rats were significantly higher than that of control rats (P0.05). CONCLUSION: Increase in the aerobic capacity, decrease in the glycolytic capacity, and disturbance of lipid and energy metabolism were found in diaphragm of 4th week diabetic rats.

Objectives To construct a small interfering RNA (siRNA) targeting vascular endothelial growth factor (VEGF) in eukaryotic expression vector, and to assess effects of this vector on proliferation and apoptosis of malignant melanoma cell line A375. Methods pU-VEGF-siRNA plasmid was transfected into A375 cells by electroporation. VEGF mRNA and protein were detected by reverse transcription polymerse chain reaction (RT-PCR) and ELISA, respectively, in A375 cells after gene transfer. Proliferation of A375 cells was assessed by cell counting. Human umbilical vein endothelial cells (ECV-304) were cultured in medium containing supernatants of treated and untreated A375 cells, and their viability was tested by cell counting. Apoptosis of A375 cells was observed by flow cytometry (FCM). Results VEGF mRNA and protein were significantly decreased in the experimental group, compared to those in the controls (P