OBJECTIVE -To evaluate the intravitreous concentration of vascular cell adhesion molecule (VCAM)-1 in diabetic patients with proliferative diabetic retinopathy (PDR) and the relationship of VCAM-1 with vascular endothelial growth factor (VEGF).RESEARCH DESIGN AND METHODS -Serum and vitreous fluid samples were obtained simultaneously at the onset of vitrectomy from 20 diabetic patients with PDR and 20 nondiabetic control subjects with nonproliferative ocular disease. Both groups were matched by serum levels of VCAM-1 and VEGF. VCAM-1 and VEGF were determined by enzyme-linked immunosorbent assay. Statistics were determined using the Mann-Whitney U test and Spearman's rank correlation test.RESULTS -The intravitreous concentration of VCAM-1 was significantly elevated in diabetic patients with PDR compared with control subjects (26 ng/ml [19 -118] vs. 22 ng/ml [20 -47], P Ͻ 0.05). A direct correlation between VCAM-1 and total vitreous proteins was detected in diabetic patients (r ϭ 0.64, P ϭ 0.003), but not in control subjects. After adjusting for total intravitreous proteins, VCAM-1 was significantly lower in diabetic patients with PDR than in control subjects (8.2 ng/ml [4 -31.4] vs. 43.1 ng/ml [9.7-100], P Ͻ 0.001). Intravitreous VEGF concentrations were higher in patients with PDR than in control subjects in absolute terms (1.34 ng/ml [0.16 -6.22] vs. 0.009 ng/ml [0.009 -0.044], P Ͻ 0.0001) and after correcting for total vitreal proteins (0.33 ng/ml [0.01-2.3] vs. 0.013 ng/ml [0.003-0.035], P ϭ 0.0001). Finally, the vitreous ratio of VCAM-1 to proteins correlated with the vitreous ratio of VEGF to proteins in both diabetic patients (r ϭ 0.74, P ϭ 0.001) and control subjects (r ϭ 0.84, P ϭ 0.005).CONCLUSIONS -The low proportion of VCAM-1 in relation to total vitreal proteins observed in diabetic patients with PDR suggests that VCAM-1 is quenched by diabetic retina. In addition, the direct correlation detected between VCAM-1 and VEGF suggests that cellular adhesion and neovascularization may be linked processes.
Diabetes Care 24:516 -521, 2001P roliferative diabetic retinopathy (PDR) is characterized by extensive neovascularization and vessel intrusion into the vitreous body, with subsequent bleeding and scarring surrounding new vessels, leading to severe visual impairment. Ischemic areas of the retina seem to be essential stimuli for the angiogenic process mediated by specific growth factors. This includes the expression of vascular endothelial growth factor (VEGF) by retinal glial cells (1) and vascular endothelial cells (2). It is thought that capillary occlusion by increased adhesion of leukocytes and macrophages to the endothelium has a crucial role in the process of retinal ischemia (3). In addition, monocytes exposed to glycated collagen show increased adhesiveness (4), and several studies indicate that circulating leukocytes are activated in diabetic patients (5,6).Vascular cell adhesion molecule (VCAM)-1, a member of the immunoglobulin supergene family of cellular adhesion molecules, is involved in the re...
Although the activity of the nitric oxide pathway is increased in patients with cirrhosis and might contribute to the hemodynamic alteration, other factors are involved. Interleukin-6, possibly through nitric oxide-independent mechanisms, also might play a role in the vasodilatation of cirrhosis and the pathogenesis of hepatic encephalopathy.
We studied the activity of adenosine deaminase in the cerebrospinal fluid of 40 normal controls and 205 patients who were grouped according to disease (tuberculous, viral, and purulent meningitis; neoplasms; stroke; and miscellaneous). The mean enzyme value was clearly higher for the patients with tuberculous meningitis (15.7 +/- 4.3 U/liter) than for the other patients (1.4 +/- 1.5 U/liter). The sensitivity of the test for diagnosing tuberculous meningitis was 1 and specificity, 0.99. The enzyme activity, as well as progression of the disease, was studied in 32 patients with tuberculous meningitis. A significant rise in levels of enzyme was observed during the first 10 days of therapy, was followed by a gradual decline, and reached normal values after three to four months of treatment. Two patients showed substantial increases that coincided with the development of complications. The test proved to be a simple and reliable method for early diagnosis and follow-up of tuberculous meningitis.
Background: Cytokines produced in mesenteric lymph nodes of cirrhotic rats with bacterial translocation may participate in circulatory alterations of cirrhosis. Aim: To investigate whether cirrhotic patients present an increased local generation of cytokines in mesenteric lymph nodes. Methods: Mesenteric lymph nodes from 26 cirrhotic and 10 control patients were assessed for tumour necrosis factor α (TNF) and interleukin 6 mRNA and protein expression by competitive reverse transcription-polymerase chain reaction, and by enzyme immunoassay and immunohistochemistry, respectively. Results: Interleukin 6 levels were not different between cirrhotics and controls. Protein and mRNA TNF levels in mesenteric lymph nodes from cirrhotics were higher than in controls (p<0.05). Tissue expression of TNF by immunohistochemistry was more abundant in cirrhotics. Ascitic patients showed higher TNF levels (47 (34-54) pg/mg protein) than patients without ascites (18 (17-25) pg/mg protein) (p<0.001). Elevated TNF levels (>28 pg/mg protein) in cirrhotics were associated with a higher ChildPugh score, the antecedent of ascites, a lower prothrombin rate, and higher bilirubin and blood TNF levels. The strongest association, confirmed by multivariate analysis, was with the presence of ascites (p<0.001). Bacterial infections after transplantation, mainly by enteric bacteria, were only detected in patients with high TNF levels in mesenteric lymph nodes (33% of patients; p=0.05). Conclusion: Patients with advanced liver cirrhosis, and especially with ascites, have increased local production of TNF in mesenteric lymph nodes that, in common with experimental cirrhosis, may also be induced by bacterial translocation.
SUMMARY We studied the activity of adenosine deaminase in the peritoneal fluid of 66 patients who were divided into five groups according to causes of ascites as follows: tuberculous peritonitis (group I), septic peritonitis (group II), secondary to malignant tumours (group III), miscellaneous conditions (group IV), and control subjects of transudates (group V). In patients with tuberculous peritonitis the enzyme activity was significantly higher than for the rest of the groups (p
scite is a Brooklyn-based startup that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.