Pulmonary mixed-function oxidation: stimulation by glucose and the effects of metabolic inhibitors

Substrate requirements for pulmonary mixed-function oxidation of p-nitroanisole to p-nitrophenol were evaluated using the isolated perfused rabbit lung and a lung microsomal fraction. Addition of glucose (5 mM) to the lung perfusate (Krebs bicarbonate buffer) increased the mean rate of p-nitroanisole oxidation by 25–55 per cent; addition of pyruvate (5 mM) or palmitate (0.5 mM) gave similar results. Sucrose (5 mM) had no effect. Antimycin A, KCN, oligomycin and bis-hexafluoroacetonyl acetone (an uncoupling agent) markedly depressed p-nitroanisole metabolism by the isolated lung. KCN also inhibited p-nitroanisole metabolism by lung microsomes, but antimycin A was without effect. These results indicate that pulmonary mixed-function oxidation requires substrate for intermediary metabolism as well as ATP, for maintenance of maximal rates. Glucose and mitochondrial substrates are equally effective in providing the energy requirements and the reducing potential for this reaction.     

Disulfiram alters dopamine metabolism at sites in rat's forebrain as detected by push-pull perfusions

WEINER, H., C. W. SIMPSON, J. A. THURMAN AND R. D. MYERS. Disulfiram alters dopamine metabolism atsites in rat's forebrain as detected by push-pull perfusions. BRAIN RES. BULL. 3(5) 541–548, 1978.—The effect of tetraethylthiuramdisulfide (disulfiram) on the catabolism of dopamine within discrete regions of the brain was investigated in the unrestrained rat. After a guide cannula had been implanted stereotaxically, a given subcortical site was radiolabeled with ¹⁴C-dopamine (DA) by microinjecting 2.0 μCi in 2.0 μl. Successive push-pull perfusates collected from each tissue were assayed by paper electrophoresis for the separation of DA metabolites. When disulfiram, a potent aldehyde dehydrogenase (ALDH) inhibitor, was given intragastrically in a clinically efficacious dose of 200 mg, the formation of the acids DOPAC and HVA was inhibited within perfusates of the caudate nucleus and nucleus accumbens. However, following disulfiram treatment, the proportion of alcohol metabolites did not differ from the control level in the untreated rat. The level of ALDH decreased by approximately 50% in these subcortical nuclei following the inhibition of the enzyme by disulfiram. Conversely, in samples of perfusate obtained from ¹⁴C-labeled sites within inferofrontal cortex, periform cortex, diagonal band of Broca, lateral-posterior caudate nucleus, tuberculum olfactorium, lateral olfactory tract or the olfactory nuclear complex, the proportion of DA metabolites remained stable. Generally, a low rate of deamination of the exogenously injected DA occurred within perfusion sites in the ventrobasal forebrain, whereas an intermediate rate of deamination was noted in samples collected at more dorsal loci. Thus, clearcut regional differences in DA catabolism occur in the brain of the living animal, which may depend upon the characteristics of the dopaminergicrich area of the rat's brain.     

Multispectral analysis of magnetic resonance images

Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study.     

EMG and histochemical findings in neurogenic atrophy with electrode localisation.

A new technique permitting electromyographic electrode localisation during open muscle biopsy is described. Using this technique recordings were made from biceps brachii from 22 normal subjects and 19 patients with neurogenic atrophy. Motor unit potential duration and onset interspike interval were the best predictors of histochemical evidence for atrophy. Of patients with neurogenic atrophy, polyphasic potentials and increased rise time of the major spike were found in 18 and 10 cases respectively. Abnormal motor unit potentials were always associated with findings of atrophy. However, normal duration, amplitude, and recruitment intervals occurred in 36%, 58% and 50% respectively of subjects with neurogenic atrophy in the region of the recording.     

Describing community needs: examples from the Circles of Care initiative

The assessment of community needs was one of the key foundations of the Circles of Care planning effort. Grantees identified a range of needs at the child, adolescent, family, programmatic, and community levels. This information, along with an emphasis on the importance of each community's history and culture, served as an important guide for each program as they developed their model systems of care.     

Acute ischemic stroke: emergent evaluation and management

This article discusses stroke, the third leading cause of death and number one cause of adult disability in the United States, inflicting a devastating physical, emotional, and financial toll on its victims and their families. The last decade has seen the emergence of new treatments for acute stroke, energizing stroke care providers and spreading a sense of optimism among them. Because effective stroke treatment is extremely time-dependent, it is paramount that emergency physicians understand and excel in their critical role at the forefront of stroke management. This article outlines the emergent evaluation and management of acute ischemic stroke, emphasizing the importance of the emergency physician in acute stroke treatment.     

Trends in hospitalization associated with traumatic brain injury.

CONTEXT: Traumatic brain injury (TBI) is associated with more than 50000 deaths in the United States each year, and recent observations suggest a substantial decline in TBI-related hospitalizations and deaths. OBJECTIVE: To analyze long-term trends in TBI-related hospitalization in the United States. DESIGN, SETTING, AND PARTICIPANTS: Analysis of existing data from 1980 through 1995 from the National Hospital Discharge Survey, an annual survey representing the US general population. The number of participating hospitals ranged from 400 to 494. MAIN OUTCOME MEASURES: Annual rates of TBI-related hospitalization, stratified by age, sex, severity of injury, and outcome. RESULTS: The annual number of TBI cases identified from the sample during the study period ranged from 1611 to 3129. Overall rates of hospitalization for TBI declined an estimated 51%, from 199 to 98 per 100000 per year. When analyzed by severity of injury, mild TBIs declined most during this period, from 130 to 51 hospitalizations per 100000 per year (61% decline; P<.001 compared with intermediate and severe TBI). The decline was greatest among those aged 5-14 years (-66%) and least among those aged 65 years or older (-9%). The ratio of male to female rates showed little variation during the study period (ratio, 1.8; 95% confidence interval [CI], 1.6-2.0), as did the in-hospital mortality rate (mean, 5.3 per 100000; 95% CI, 3.6-7.1). CONCLUSIONS: Changes in hospital practices may be a major factor in the declining rates of TBI-related hospital admissions. These practices increasingly appear to exclude persons with less severe TBI from hospital admission and shift their care to outpatient settings.