PubMed Health⌕ Search

Biomedical subjects

R S Burns

Publications and source records attributed to R S Burns.

11 recordsLinked to original sources
PubMed1991

Levels of pros-methylimidazoleacetic acid: correlation with severity of Parkinson's disease in CSF of patients and with the depletion of striatal dopamine and its metabolites in MPTP-treated mice.

The cerebrospinal fluid (CSF) levels of pros-methylimidazoleacetic acid (p-MIAA) in thirteen medication-free patients with mild to moderate Parkinson's disease were highly correlated (Spearman's rho = 0.749, p less than 0.005) with the severity of signs of the disease as scored on the Columbia University Rating Scale. Levels of p-MIAA in males (n = 8) and females (n = 5) were each significantly correlated with scores of severity (rho = 0.78, p less than 0.05 and rho = 1.0, p less than 0.05, respectively). In C57BL/6 mice treated with 1-methyl-4-phenyl-1,2,3,6-tetra-hydropyridine (MPTP), levels of p-MIAA were significantly correlated with the depleted levels of dopamine (r = 0.85, p less than 0.01), homovanillic acid (r = 0.79, p less than 0.02), 3,4-dihydroxyphenylacetic acid (r = 0.84, p less than 0.01) and norepinephrine (r = 0.91, p less than 0.002) in striatum, but not in cortex of the same mice. No such correlations were observed in either striatum or cortex of saline-treated control mice. Mean levels of p-MIAA in CSF did not differ significantly between patients and age-matched controls; and mean levels of p-MIAA in striatum did not differ between MPTP-treated mice and controls. The simplest hypothesis to account for these strong correlations in the absence of differences in mean levels of p-MIAA is that accumulation of p-MIAA [or process(es) that govern its accumulation] influences a failing nigrostriatal system. It is also possible (in analogy with findings in other diseases and with other drugs) that measurements of the putative metabolite(s) of p-MIAA may distinguish the patients and the MPTP-treated mice from their respective controls. Elucidation of the processes that regulate formation and disposition of p-MIAA in brain and information on the neural effects of p-MIAA, its precursors and its putative metabolites may yield insight into factors that regulate the progression of Parkinson's disease, and may shed additional light on the cause(s) of this disease.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1991

Subclinical damage to the nigrostriatal dopamine system by MPTP as a model of preclinical Parkinson's disease: a review.

The study of subtle changes in motor and cognitive function after exposure to MPTP might serve as a guide to the very earliest stages of Parkinson's disease. Studies in nonhuman primates and man exposed to MPTP who remained asymptomatic or recovered completely are reviewed. The question of the relationship between the degree and extent of damage to the nigrostriatal dopamine system and changes in motor and cognitive (behavioral) function is addressed. What guidance they provide in the study of subclinical or preclinical Parkinson's disease is discussed.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1990

Alterations in prealbumin concentration after adrenal autotransplantation for Parkinson's disease.

The cerebrospinal fluid of eight patients with Parkinson's disease who underwent adrenal medullary autotransplantation was analyzed using SDS-polyacrylamide gel electrophoresis. A protein, subsequently identified as prealbumin, was noted to change in concentration over the intraoperative to 18-month postoperative time course. The qualitative changes observed on visual inspection were confirmed and quantified using laser densitometry. The concentration of prealbumin increased by an average of 90% when the intraoperative and 12-month samples were compared. This increase persisted at 18 months. The ratio of prealbumin to albumin also increased from intraoperative to 12 months by an average of 56%. This suggests that the increases in PA are the result of choroid plexus activation rather than a nonspecific breakdown of the blood-brain barrier. Given the association of prealbumin with other nervous system diseases, as well as its known ability to bind multiple substances, these findings may have important implications. Alterations in prealbumin may be responsible for the improvement seen in some patients who receive adrenal medullary autotransplants. Alternatively, prealbumin may be implicated in the pathophysiology of Parkinson's disease.

Adrenal Medulla↗
PubMed1978

Phencyclidine deaths.

The potential for a pharmacologic "overdose" and the cause of death associated with phencyclidine abuse is discussed. Nineteen deaths associated exclusively with phencyclidine intoxication have been documented. In 13 cases the immediate cause of death was asphyxia by drowning or trauma with lower levels of phencyclidine present suggesting behavioral toxicity. In two cases, the presence of phencyclidine in high concentrations constituted the only finding, and the probable cause of death was primary respiratory depression accompanied by seizure activity. A secondary drug effect or concurrent disease process may have contributed to the death of the remaining four individuals.

Adolescent↗
PubMed1978

Phencyclidine use among youth: history, epidemiology, and acute and chronic intoxication.

Phencyclidine use appears to be in a growth phase nationally. Factors contributing to the increasing popularity include the user's ability to control the dosage, an understanding of the immediate effects, and its availability. Those most at risk appear to be young Caucasian males. Phencyclidine-related problems are often like tips of icebergs, the underlying causes of which are hidden from public view. The problems often surface in the form of speech difficulties, memory loss, thinking disorders, personality changes, paranoia, severe depression, violence, accidents, suicides and homicides. Of particular concern to law enforcement personnel is the upsurge in phencyclidine-related violent crimes and carrying of weapons by users to protect themselves from their imagined persecutors. The evidence currently available supports the assumption that if there is a solution to the problem of phencyclidine abuse, that solution is prevention. Therefore, medical personnel and others within the helping professions must be alerted to the fact that phencyclidine is not just another drug problem. The findings from users we have already studied strongly suggest that phencyclidine is not an "upper" or a "downer," but perhaps an "insideouter", with longer term implications.

Adolescent↗
PubMed1975

Phencyclidine--states of acute intoxication and fatalities.

Phencyclidine is now one of the most frequently used main ingredients of "street drug" preparations. Its effects are highly dose dependent and three varieties of acute intoxication have been seen clinically associated with different dosages and routes of administration. Most persons using phencyclidine smoke it sprinkled on parsley in low doses. The presence of horizontal and vertical nystagmus associated with hypertension in a patient who is agitated or comatose are diagnostic of a phencyclidine intoxicated state. Sensory isolation and intravenous administration of diazepam in the event of seizure activity have proved effective in the treatment of acute intoxicated states. Phencyclidine has pronounced behavioral toxicity and several deaths due to this agent have now been documented. It is unknown whether seizure activity or respiratory depression is the primary cause of death in pharmacological overdoses.

Diagnosis, Differential↗