Objective To observe the histopathologic features and expression patterns of tumor necrosis factor-alpha; (TNF-alpha;), interleukin-1beta;(IL-1beta;) and Escherichia coli lipopolysaccharide (LPS) in the rat vitreous with LPS inducedendophthalmitis. Methods Wistar rats were randomly divided into saline control group (SC,136 rats),endophthalmitis group (EO, 168 rats)and blank control group (BC,12 rats).EO group received an intravitreal injection of 5 mu;l LPS; SC group received 5 mu;l sterile saline and no intervention for BC group.Six,12,24,48, and 72 hours,5 and 7 days after injection, intraocular inflammation were observed and the eyes and vitreous were collected for histopathological examination and measurement of TNF-alpha;, IL-1beta; and LPS expression. Results Severe inflammatory responses in the eyes were observed in EO group between six and 72 hours after LPS injection,ocular inflammation subsided seven days after LPS injection. In the vitreous, a peak neutrophil count was observed at 24 hours (1224.64plusmn;132.2) cells/eye that rapidly declined at 72 hours (342.25plusmn;47.7) cells/eye. The levels of TNF-alpha; and IL-1beta; in EO group were peaked at 24 hours with (996.18plusmn;89.45) and(5556plusmn;1440)pg/ L, respectively;Persisted at 48 hours and began to decline rapidly thereafter. Seven days after LPS injection, levels of TNF-alpha; and IL-1beta; returned to baseline with (22.16plusmn;5.84)and (73.7plusmn;18.7) pg/L, respectively. LPS concentration in EO group decrease rapidly at 72 hours with (11.03plusmn;3.41) ng and disappear on days 7 with (0.22plusmn;0.08) ng after LPS injection.Conclusions Massive neutrophils infiltration, high levels expression of TNF-alpha; and IL-1beta; and spontaneous elimination of bacterial elements in vitreous cavity were major pathologic characteristics in this experimental model. The expression patterns of TNF-alpha;,IL-1beta; were in accord with LPS clearance process.
Objective To observe the pathological and functional changes of retinal photochemical damages exposed to green flurescent light. Methods The Sprague Dawley rats were continually exposed to green fluorescent light with an illuminancem level of (1 900plusmn;106.9) Lx for 24 hours.The changes of retinal morphology and morphometrics and flash electroretinogram were studied before light exposure and at the 6th hour,6th day and 14th day after light exposure. Results At the 6th hours after light exposure,the outer nuclear layer(ONL)of retina becoma thinner compared with that bfore light exposure.The thickness of ONL decreased by 23.91% and the inner and outer segments appeared disorderly arranged.At the 6th day after light exposure the thickness of ONL is thinner than that at the6th hour,i.e.decreased by 46.6%. At the 14th day after light exposure the thickness of ONL decreased by 42.40%.Flash electroretinogram showed that the amplitudes of a and b wave decreased continuously at the 6th hour and 6th day and unrecovered at the 14th day after light exposure. Conclusion This model might be an ideal one for research on retinal photochemical damage. (Chin J Ocul Fundus Dis,1998,14:101-103)
Objective To explore the histopathological changes of the radial optic neurotomy (RON) in human eyes, and to establish the theoretical foundation for the effective RON. Methods Ten patients with unaffected eyeball or optic disc who had undergone ophthalmectomy (7 patients) or orbital exenteration (3 patients) because of intraocular or orbital tumor were gathered. A double-incision in pars plana was performed. One was inserted into illuminating fiber, and an other was inserted into a standard microvitreoretinal (MVR) blade (unbent MVR blade in 4 patients and bent ones in 6; radial incision on nasal side of the optic disc in 4 patients and on both nasal and temporal side in 6). The histopathological examination was performed to observe the location and depth of the incision. Results Eleven incisions were found in 8 out of 10 patients, of which surgical spaces can be observed clearly. Three incisions were obliquely inserted into the optic nerves, 5 sieve plate lateral incisions had the surgical intervals conne cted with the subarachnoid spaces, and 3 incisions caused obvious damage of retinal ganglion cell axons due to the position close to the center. Nine incisions approached to the retrolaminal level, and the other 2 reached the laminal and pr elaminal level respectively. Injured retina beside the optic disc in 1 incision was found. Central retinal vessels were not damaged. Conclusions An optimal incision may be in the edge of the lamina cribrosa, whose depth should be in the level of lamina cribrosa and retrolamina, with surgical intervals connected with the subarachnoid spaces. (Chin J Ocul Fundus Dis,2004,20:67-70)
Objective To observe the effect of high glucose on the expression of activating transcription factor 4 (ATF4) in cultured retinal Muuml;ller glia cells. Methods The retinal tissue of Sprague-Dawley (SD) rats was collected, and Muuml;ller cells were isolated and cultured. The glial fibrillary acidic protein (GFAP) and glutamine synthetase (GS) of Muuml;ller cells were identified by streptavidin-biotin-peroxidase complex. Cultured rat Muuml;ller cells were divided into control group (5.5 mmol/L glucose), group A (20 mmol/L glucose), group B (30 mmol/L glucose) and group C (40 mmol/L glucose). ATF4 protein expressions in Muuml;ller cells of four groups were measured by Western blot four days after cultured. Results GFAP and GS expressed in more than 95% of Muuml;ller cells. Over 95% of Muuml;ller cells of group A, B and C were positive for GFAP and GS. Western blots indicated that ATF4 protein in group A, B and C increased obviously compared with the control group (q=0.293, 0.754,0.484;P<0.05). Conclusion High glucose can increase the expression of ATF4 protein and cause endoplasmic reticulum stress in retinal Muuml;ller glia cells in vitro.
ObjectiveTo explore apoptosis of acinar cells during pancreatic allograft rejection in rats.MethodsGroups of Wistar rats underwent heterotopic pancreaticoduodenal transplantation from syngenic Wistar of allogenic SD rats. The grafts were harvested on postoperative day 3, 5 and 7. All graft samples were subjected to histological examination and apoptotic cells of graft acinar cells using in situ terminal deoxynucleotidy1 transferasemediated dUTP nickend labeling (TUNEL). Histopathological rejection score and apoptotic index (AI) were analyzed. ResultsThe incidence of apoptotic cells was increased steadily over time in allografts, in contrast with syngenic grafts. The apoptotic cells in allografts were mainly acinar cells and few infiltrating lymphocytes. A significant correlation between apoptotic index and histopathological rejection score was noted.ConclusionTUNEL can display apoptosis of single cell in situ. Apoptosis is an important mechanism of tissue injury in acute pancreatic allograft rejection in rats. Acinar cell apoptosis can be used as a valuble index to estimate the injury of grafts and to monitor the acute rejection.
Objective To investigate the effect of imbedding chemotherapy of sustained release of 5-fluorouracil on the healing of colonic stoma in dog. Methods Twenty-eight adult hybrid dogs were randomly divided into chemotherapy group (n=22) and control group (n=6). The canine sigmoid colon were firstly detached and then anastomosed via median abdominal incision, 200 mg sustained release of 5-fluorouracil was imbedded in the mesentery 1.0-1.5 cm away from colonic stoma in chemotherapy group, whereas the control substance was injected into the dogs in control group. Tissue samples were collected from mesentery and stomas on 3, 5, 7, 10 and 15 days after operation, respectively, in order to observe the healing of stoma. The drug concentrations in the stoma and in the tissues that were 0, 1, 3, 5, 7, 10 and 15 cm away from the imbedding point were also measured by high performance liquid chromatographymethod at different phases. Results The tissues from colonic stoma only showed inflammatory reaction at early stage, with no necrosis and cellular degeneration. It was observed that the stoma healed basically on the tenth day after operation. The drug concentrations in the tissues gradually decreased at the range of 0-15 cm over time, but all of which were higher than the anti-tumor effective concentration (0.10 μg/g). Conclusion The imbedding chemotherapy of sustained release of 5-fluorouracil in mesentery has little effect on the healing of stoma, and it could remain an effective anti-tumor concentration in a period of time.