Search PubMed⌕ Search

Biomedical subjects

J Desemone

Publications and source records attributed to J Desemone.

6 recordsLinked to original sources

Morphological and physiological characteristics of pancreas-specific venular permeability induced by Monastral blue B.

Leaky blood vessels in the microcirculation can be detected in vivo by injecting an animal with colloidal pigments such as Monastral blue B (MbB) or carbon black. We have previously used the MbB labeling method in the spontaneously diabetic BB/W or rat and detected increased vascular permeability restricted to the venules of the pancreas. We now report the morphological and physiological characteristics of this phenomenon in additional rat strains. Susceptibility to pancreatic labeling with MbB among strains was found to be a highly variable, heritable characteristic, but in no strain did vessels label in any organ other than the pancreas. Pancreatic labeling by MbB was dose dependent, was observed in both inbred and outbred rats, and was not related to major histocompatibility complex haplotype. Enhanced permeability was induced by MbB within minutes of its administration as a result of the formation of gaps between endothelial cells; these gaps then closed within 15 min. Pretreatment with silica or carrageenan, agents known to affect macrophage function, completely blocked pancreatic MbB venular labeling, but the effect was reversible over a period of several days. We hypothesize that presence of MbB in the pancreatic circulation induces organ-specific venular leakage either by a direct effect on pancreatic endothelial cells or via the local release of a mediator.

Animals↗

The BB rat.

Explore the source record for details and available documents.

Animals↗

A pancreatic venular defect in the BB/Wor rat.

BB rats develop spontaneous autoimmune diabetes mellitus characterized morphologically by insulitis, an inflammatory lymphocytic infiltration of the islets of Langerhans. To investigate the role of the vascular endothelium of the pancreas in this destructive process, the authors injected diabetes-prone (DP) and diabetes-resistant (DR) BB/Wor rats as well as other nondiabetic strains of rats with Monastral blue B, a colloidal pigment that identifies leaky microvasculature. They found evidence of a venular defect limited to the pancreas that is specific to the BB rat. Light- and electron-microscopic evidence suggests that this defect is due to a population of trapped (marginating) intravascular monocytes, which may be activated by the colloidal pigment and release vasoactive mediators.

Animals↗

Pancreas-specific venular labeling by monastral blue B in the BB rat: modulation by prostaglandins and their inhibitors.

Leaky blood vessels in the microcirculation can be detected in vivo by injecting an animal with colloidal pigments like Monastral blue B (MbB). We have previously used this labeling method in the BB rat, an animal model of spontaneous autoimmune diabetes, and detected increased vascular permeability restricted to the venules of the pancreas. The earlier data suggested that pancreata of animals susceptible to labeling contain trapped intravascular monocytes that are activated to release vasoactive mediators after phagocytosis of MbB. To explore these observations further, we investigated the effects of prostaglandins on this system. Prostaglandins are known to be important mediators of inflammatory responses and to modulate the expression of disease in other animal models of autoimmunity. We now report that MbB-induced pancreatic labeling is modulated by misoprostol (an analogue of prostaglandin E1), prostaglandins of the E series, and inhibitors of prostaglandin synthesis. The nonsteroidal anti-inflammatory drugs ibuprofen and ketorolac both reduced the intensity of labeling in susceptible BB rats in a dose dependent manner. In contrast, both misoprostol and prostaglandin E2 given at low doses induced pancreatic permeability in the labeling-resistant Wistar Furth rat. To extend this finding, we also tested much higher drug doses, since at high concentrations, E series prostanoids exert anti-inflammatory effects. We observed that large doses of prostaglandin E1, prostaglandin E2, and misoprostol all suppressed labeling in the BB rat. We conclude that presence of MbB in the pancreatic circulation of the rat induces organ specific venular leakage by an inflammatory process involving prostaglandins.

Animals↗

Comparison of diabetes care provided by an endocrinology clinic and a primary-care clinic.

OBJECTIVE: To compare the quality of ambulatory diabetes care provided by physicians in an endocrinology clinic with that in a primary-care clinic. METHODS: We conducted a retrospective study of the medical records of patients with diabetes treated for 2 to 4 years in an endocrinology clinic and a primary-care clinic at an academic medical center. Adherence to American Diabetes Association (ADA) clinical practice recommendations and hemoglobin A(1c) (HbA(1c)) levels were assessed in randomly chosen patients-a total of 68 patients from the primary-care clinic and 105 patients from the endocrinology clinic, with total patient-years of follow-up of 241 and 370, respectively. RESULTS: In six of seven areas assessed, the endocrinology clinic was significantly more compliant with ADA recommendations than was the primary-care clinic: queries about hypoglycemia (88% versus 20%); frequency of glycated hemoglobin determinations (3.3 versus 2.1 per patient/yr); yearly lipid panel (44% versus 25%); and yearly ophthalmologic (90% versus 50%), neurologic (56% versus 37%), and foot (88% versus 59%) examinations (all P<0.001). The rate of yearly proteinuria evaluations was similar in the two clinics (66% versus 65%). On assessment of all patients, the mean HbA(1c) level was significantly lower in the endocrinology clinic (8.29%) than in the primary-care clinic (8.73%) (P = 0.01). CONCLUSION: Adherence to ADA clinical practice recommendations was significantly better in the endocrinology clinic than in the primary-care clinic. This finding and the significantly lower levels of HbA(1c) in patients in the endocrinology clinic setting would be expected to translate into improved long-term patient outcome.

Adult↗