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C Butler

Publications and source records attributed to C Butler.

120 records · Page 7Linked to original sources
PubMedDate not supplied

Antihistamines reverse blood-ocular barrier breakdown in experimental diabetes.

Retinal and other tissue histamine synthesis is increased in experimental diabetes; histamine infusion causes blood-ocular barrier breakdown in nondiabetic rats. We have examined the hypothesis that antihistamines prevent blood-ocular barrier breakdown in streptozotocin diabetes using male Sprague-Dawley rats held 28 days. During the last 7 days they were divided into these treatment groups: control (C), untreated diabetic (D), diabetic rats receiving diphenhydramine-HCl (B), diabetic rats receiving ranitidine (R) and diabetic rats receiving diphenhydramine and ranitidine (BR). Vitreous albumin content was measured 6 hr following fluorescein isothiocyanate bovine serum albumin (FITCBSA) injection. Data show that D had a 98.3% increase in vitreous body FITCBSA over C (p less than 0.05) while B and R showed respective decreases of 34.9% and 51.4% compared to D, R being significantly lower than D (p less than 0.05). BR showed a decrease of 71% (p less than 0.05) compared to D, and R and BR groups were not significantly different from C (p less than 0.05). Leakage into the vitreous was from the retina, not the ciliary body. These data indicate that 1) experimental diabetes results in elevated blood-ocular barrier permeability, which can be reversed by diphenhydramine-HCl and ranitidine; and 2) histamine H1- and H2-receptor activation and interaction by altered endogenous histamine metabolism may mediate blood-ocular barrier breakdown, implicating a pathogenic role of histamine in diabetic retinopathy.

Animals↗
PubMedDate not supplied

Astemizole reduces blood-retinal barrier leakage in experimental diabetes.

We examined the potential of astemizole, a histamine H1-receptor antagonist that does not cross the blood-brain barrier, to reverse blood-retinal barrier leakage to albumin in streptozotocin diabetic rats. Four groups of nondiabetic and four groups of diabetic rats received vehicle or astemizole at dosages of 5, 10, or 20 mg/kg body weight for days 22-28 of a 28-day holding period. There were no significant differences in nondiabetic plasma-vitreous albumin ratios between animals receiving vehicle or any of the three astemizole dosages. Only diabetic rats receiving vehicle showed a significant (p < 0.05) 100% increase in the plasma-vitreous albumin ratio over their nondiabetic counterparts. Diabetic rats receiving either 5, 10, or 20 mg/kg astemizole exhibited total normalization of vitreous albumin accumulation, despite persistence of diabetes. These data indicate that astemizole, an H1-receptor antagonist that does not cross the blood-retinal barrier, is effective in reversing blood-retinal barrier leakage of albumin in experimental diabetes.

Animals↗
PubMedDate not supplied

Morphology and function of cultured human fetal pancreatic cells transplanted into athymic mice: a longitudinal study.

Islet-like cell clusters generated from human fetal pancreases between 18-24 wk gestation were able to grow and mature both morphologically and functionally after transplantation under the kidney capsule of athymic nude mice. Grafted tissue, predominantly ductal in appearance was unresponsive to glucose 2 wk after grafting. The tissue assumed the trabecular column-like architecture of adult islets by 3 mo, with a concomitant 3-4-fold increase in serum human C-peptide concentration after glucose challenge. Moreover, at that time the surface area of insulin containing cells in the graft increased 20-fold over the starting material. Exocrine components, identified by their characteristic eosinophilic secretory granules were also identified at this time. Transplanted cell clusters were capable of releasing C-peptide for at least 12 mo, when the experiment was terminated. At this time, 1 yr posttransplantation, although the proportion of insulin containing cells in the graft remained unchanged from that measured at 4 mo, a reduction in the magnitude of the C-peptide response to glucose was observed; this finding coincided with a significant mononuclear infiltrate in some areas of the transplanted tissue. In summary, human fetal pancreatic cells grown in tissue culture as cell aggregates, after transplantation under the kidney capsule, remain functionally viable for virtually the life span of immunocompromised rodents. Because of their long-term viability, the use of islet-like cell clusters is a potentially useful method to expand transplantable cells.

Animals↗
PubMedDate not supplied

Coughs and colds: nurse management of upper respiratory tract infection.

BACKGROUND: Nurses in general practice are increasingly managing minor illness. This literature review examines the management of upper respiratory tract infection (URTI) as one area of patient care where nurses can make a major contribution. CONCLUSION: The challenge for nurses is to respond to the changing healthcare environment creatively and in collaboration with doctors and patients.

Anti-Bacterial Agents↗
PubMedDate not supplied

Intrathoracic ganglionic beta-adrenergic receptors involved in efferent sympathetic regulation of the canine heart.

The enhancement of cardiac inotropism induced by electrical stimulation of acutely decentralized efferent preganglionic sympathetic axons was reduced, but still present, following intravenous hexamethonium administration (10 mg/kg). This residual enhancement was eliminated following subsequent administration of timolol (0.1 mg in 0.1 mL normal saline) into the ipsilateral stellate and middle cervical ganglia. Similar results were obtained when the order of administration of these agents was reversed. When the beta-adrenergic agonist isoproterenol (1, 2 or 5 micrograms in 1 microL of normal saline) was administered into specific loci of an acutely decentralized stellate or middle cervical ganglion, cardiac chronotropism and/or inotropism were increased; when similar injections were made into adjacent ganglionic sites cardiac responses usually were not elicited. Following hexamethonium administration similar results were obtained indicating that these effects were not primarily dependent upon nicotinic cholinergic synapses. In contrast, repeat injections of isoproterenol into the site that initiated cardiac responses when injected with isoproterenol failed to elicit any cardiac responses following local administration of timolol into the same site indicating that the effects of isoproterenol could be blocked by a beta-adrenergic receptor blocking agent. Injections of 1 to 5 micrograms of isoproterenol into a ganglion which was surgically disconnected from the heart failed to elicit cardiac responses, demonstrating that at these doses detectable activation of cardiac myocyte beta-adrenergic receptors via circulating isoproterenol which had leaked out of the ganglion did not occur. It is concluded that beta-adrenergic receptors in intrathoracic ganglia are involved in the efferent sympathetic regulation of the heart and that such receptors are associated with neurons in specific ganglionic loci.

Animals↗
PubMedDate not supplied

Prophylactic antibiotics in patients undergoing total vaginal or abdominal hysterectomy.

A prospective study to evaluate the effect of antibiotic prophylaxis in 57 patients undergoing total abdominal or vaginal hysterectomy was conducted at Arlington Hospital. Patients were assigned randomly to one of two regimens. Group I received a single 1 gram preoperative dose of Cefotaxime (Claforan). Group II received a 2 gram dose of Cefoxitin (Mefoxin) preoperatively and also four 2 gram doses postoperatively. There was no significant group difference in the incidence of postoperative infection or in the mean duration in hospital stay. One dose of Cefotaxime was as effective as five doses of Cefoxitin in preventing infection.

Adolescent↗