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D Neely

Publications and source records attributed to D Neely.

25 records · Page 2Linked to original sources

Enhanced pilocarpine-induced oral activity responses in neonatal 6-OHDA treated rats.

Neonatal destruction of rat nigrostriatal dopaminergic fibers results in an enhanced oral activity response to both dopamine (DA) D1 and serotonin (5-HT) agonists. Because cholinergic systems represent another one of the neural circuits involved in oral behavior, it was of interest to determine whether muscarinic receptors might also be sensitized in the lesioned rats. At 3 days after birth, rats were pretreated with desipramine HCl (20 mg/kg, IP) 1 h before 6-hydroxydopamine (6-OHDA) HBr (100 micrograms in each lateral ventricle) or saline-ascorbic acid (0.1%) vehicle. Between 2 and 4 months, behavioral supersensitivity to a D1 agonist (SK&F 38393) and 5-HT agonist (m-chlorophenylpiperazine; m-CPP) was established before rats were challenged with the muscarinic receptor agonist, pilocarpine HCl (0.125 to 10.0 mg/kg, IP). The pilocarpine dose-effect curve was shifted to the left, with a maximal effect of 63.7 +/- 8.6 oral movements being produced by a 1.0 mg/kg pilocarpine HCl dose in the 6-OHDA lesioned rats, versus 15.0 +/- 2.4 oral movements in the control group (p < 0.001). The enhanced response to pilocarpine was attenuated by the muscarinic receptor antagonist, scopolamine HCl (0.1 mg/kg IP). These findings indicate that neonatal 6-OHDA treatment produces supersensitization of muscarinic receptors in rats.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗

The effect of intravenous magnesium administration on aortic, right atrial and coronary perfusion pressures during CPR in swine.

OBJECTIVE: To determine the effect of magnesium administration on aortic, right atrial and coronary perfusion pressure (CPP) during cardiopulmonary resuscitation (CPR). DESIGN: Twelve swine weighing 23.2 +/- 3.1 kg were instrumented for CPP, aortic systolic (AOSP) and aortic diastolic (AODP) pressures. INTERVENTION: Ventricular fibrillation was induced and after 20 min of CPR the animals were allocated to receive epinephrine 0.2 mg/kg, or epinephrine 0.2 mg/kg plus magnesium 0.14 g/kg. Epinephrine was repeated every 5 min. Arterial blood gases were determined during normal sinus rhythm and prior to drug administration. RESULTS: Pressures were recorded and averaged over four consecutive 5-min intervals following initial drug administration. AOSP, AODP and CPP were compared using an analysis of covariance. AOSP was statistically lower in the group receiving magnesium. There was a trend toward lower AODP and CPP in the group receiving magnesium as well. These statistical differences and trends were absent after adjusting for pressures during normal sinus rhythm and serum bicarbonate prior to drug administration. CONCLUSIONS: In this model of prolonged cardiac arrest, the administration of magnesium with epinephrine appeared to have a negative effect on aortic pressures during CPR. Further study is needed to determine the confounding effect of serum bicarbonate on the response to epinephrine and magnesium during CPR.

Animals↗

Stress responses after treatment of hypercholesterolaemia with simvastatin.

In order to determine whether treatment of hyperlipidaemia with simvastatin impairs exercise stress responses and so may contribute to an excess of suicides and violent deaths, the effects of simvastatin 20 mg daily and placebo on exercise physiology were compared in 19 patients. After 6 weeks of treatment there was no evidence of reduced exercise capacity, or of reduced cortisol or catecholamine responses. It is concluded that treatment of hyperlipidaemia with an inhibitor of HMG-CoA reductase does not significantly modify stress responses, and so the explanation for a possible increase in non-cardiac mortality must be sought elsewhere.

Adrenocorticotropic Hormone↗

An autopsy-based study of diagnostic errors in geriatric and nongeriatric adult patients.

One hundred sixty-two consecutive adult autopsies (87 of subjects over age 65 years and 75 of subjects aged 23 to 64 years) performed at a university hospital were studied retrospectively by six internists to determine (1) if diagnostic errors were quantitatively or qualitatively different between the two age groups; (2) if the underlying causes of error (divided into nine categories) were different or age related in any way between the two groups; and (3) any aspects of care that related age to clinical outcome. We found the frequency of major clinical/autopsy discrepancies to be similar to those in previous studies (35%), but in only 7% of cases were these likely to have affected therapy/outcome. Ther was no difference in the frequency of major discrepancies between age groups. There were significantly more "unexpected" minor discrepancies in the older patients, probably related to the multiplicity and complexity of their problems, but these would have affected therapy/outcome in only 1 (3%) of 37 cases. The most common causes of 136 clinical "errors" in 151 autopsies were, in order of frequency: a diagnostic "blind spot," a conscious decision not to pursue a clinical finding (not a real "error"), failure to account for a symptom or sign, atypical presentations, and inadequate follow-up of abnormal laboratory findings. There were no differences between the geriatric and adult groups in terms of frequency or cause of the errors. We conclude that (1) there is no difference in the diagnostic accuracy regarding cause of death between geriatric and nongeriatric patients in the acute hospital environment, and (2) closer attention to basic knowledge and clinical skills and a special focus on judgment and reasoning skills, utilizing autopsy findings among other things, will lead to even further improvement in clinical care at all ages.

Adult↗