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Biomedical subjects

R G Robinson

Publications and source records attributed to R G Robinson.

At least 253 records · Page 14Linked to original sources
PubMed1984

Effect of anterior-posterior lesion location on the asymmetrical behavioral and biochemical response to cortical suction ablations in the rat.

Small cortical suction ablations were produced at one of several stereotaxically located sites along the anterior-posterior axis of the right or left hemisphere in the rat. Analysis of variance showed a highly significant effect of lesion location in the right hemisphere on locomotor activity. The most anterior lesions produced both the most hyperactivity and also the greatest reductions in the concentrations of norepinephrine in the ipsilateral and contralateral cortex and locus coeruleus. These results suggest that the effect of cortical lesions on spontaneous activity may be graded across the right hemisphere and that the anatomy of certain neurotransmitter pathways in the cortex may help to explain both the biochemical and behavioral findings.

Animals↗
PubMed1984

Nortriptyline treatment of post-stroke depression: a double-blind study.

The efficacy of nortriptyline in the treatment of post-stroke depression was assessed by a double-blind study in thirty-four patients. Half of the patients had major depression. There was a significantly greater improvement in depression in patients treated with nortriptyline than in a similar group of placebo-treated patients. Depression was measured by the Hamilton depression scale, Zung depression scale, present state examination, and an overall depression scale. Successfully treated patients had serum nortriptyline levels in the therapeutic range. Post-stroke depressions are common, severe, and longstanding, and the demonstrated efficacy of nortriptyline provides an important addition to the treatments available for stroke patients.

Brain↗
PubMed1984

Cortical undercuts in the rat produce asymmetrical behavioral response without altering catecholamine concentrations.

Baseline spontaneous activity of male Sprague-Dawley rats was established in home running wheel cages 3 weeks prior to cortical undercutting. Rats received unilateral 2-mm-diameter circular lesions undercutting layer VI of either the left or right frontal cortex. The right hemisphere lesion group showed a 63% increase in spontaneous activity and rats with left hemisphere lesions were no more active than sham-operated controls. No significant intergroup differences in norepinephrine concentrations were noted in the frontal or posterior cortex or locus ceruleus either ipsilateral or contralateral to the lesion site. In addition, there were no significant group differences in dopamine content of the caudate nucleus. Results suggest that the lateralized neural substrates controlling locomotor asymmetry are probably postsynaptic to cortical norepinephrine fibers and may involve glutamatergic corticostriatal projections.

Animals↗
PubMed1984

Asymmetrical locomotor response to unilateral cortical injections of DSP-4.

The role of norepinephrine depletion in the lateralized production of spontaneous hyperactivity was assessed by unilateral fronto-cortical injections of either 10 or 20 micrograms of the noradrenergic neurotoxin, DSP-4 (N-2-chlorethyl-N-ethyl-bromobenzylamine hydrochloride). Ten micrograms of DSP-4 produced significant hyperkinesis only when injected into the right hemisphere. A 20 micrograms dose produced hyperactivity when injected into either hemisphere. DSP-4 injections resulted in significant NE and ipsilateral and contralateral 5HT depletions in the frontal cortex. The 20 micrograms right hemispheric injection significantly increased both DOPAC and DA levels in the contralateral caudate in a manner unrelated to behavior. These findings, in conjunction with results from previous neurotoxin studies, support a hypothesis of greater relative sensitivity to injury of right hemispheric NE terminal fields compared with injury to left hemispheric fields as demonstrated by spontaneous hyperactivity.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1984

Asymmetrical effects of cortical island lesions in the rat.

Baseline spontaneous activity of male Sprague-Dawley rats was established in home running wheel cages 3 weeks prior to receiving cortical circumscription lesions. Circumscriptions 2 mm in diameter and 2 mm deep were produced by means of a rotating microknife and were centered approximately 9.0 mm anterior to ear bar zero. Circular knife cuts of the right, but not the homologous left cortex produced long-lasting depletions of ipsilateral and contralateral fronto- and posterio-cortical NE. Right hemisphere lesions produced a 35% increase in activity while left hemispheric lesions uniformly decreased spontaneous home cage running wheel activity by 35%. These results are consistent with our hypothesis that injury to transcortical pathways (perhaps noradrenergic fibers) are sufficient to produce lateralized spontaneous hyperactivity. The possible existence of competing excitatory and inhibitory mechanisms in the left frontal cerebral cortex is discussed.

Animals↗
PubMed1984

Mood disorders in stroke patients. Importance of location of lesion.

In a selected group of right-handed patients with single stroke lesions of either the right (n = 14) or left (n = 22) hemisphere and no predisposing factors for psychiatric disorder, we found that the severity of depression was significantly increased in patients with left anterior lesions as opposed to any other lesion location. In addition, the severity of depression correlated significantly with proximity of the lesion on CT scan to the frontal pole in the left anterior group. The right hemisphere lesion group showed the reverse trend: patients with right posterior lesions were more depressed than patients with right anterior lesions, who were unduly cheerful and apathetic. These findings suggest that intrahemispheric lesion location is in some way related to mood disorder in stroke patients and that there is a graded effect of lesion location on severity of mood change. The neuroanatomy of the biogenic amine-containing pathways in the cerebral cortex might explain this graded effect and provide a neurochemical basis for the mood change.

Aphasia↗
PubMed1984

The meatal problem with TUR prostate: the value of post-operative self-dilatation.

In a preliminary retrospective study, we found that 37% of patients about to undergo a transurethral resection of the prostate had an external meatus too small to admit a 26 F resectoscope sheath. In a prospective study, a formal meatotomy was compared with an Otis urethrotomy for patients with a narrow meatus. This study was stopped because 71% of cases having a meatotomy developed strictures compared with 29% having an internal urethrotomy. In a further study of 59 patients, regular self-dilatation of the cut meatus with a plastic spigot was compared with internal urethrotomy of the meatus alone. Seven per cent of cases having self-dilatation developed strictures compared with 34% having internal urethrotomy. It was concluded that in those patients with a narrow external meatus meatotomy should not be carried out, but self-dilatation following internal urethrotomy greatly reduces the incidence of meatal strictures.

Dilatation↗
PubMed1984

A two year longitudinal study of mood disorders following stroke. Prevalence and duration at six months follow-up.

We are conducting a two year longitudinal study of mood disorders in a group of 103 stroke patients. During the first six month period following the stroke the prevalence of symptoms of major depression increased from 23 per cent to 34 per cent while the frequency of symptoms of dysthymic depression increased from 20 per cent to 26 per cent. In addition, 10 of 13 patients who had major depressive symptoms during the initial evaluation continued to have these symptoms at six months follow-up and 4 of 9 patients who had minor depression in hospital developed major depression, while 5 of 9 continued to have minor depressive symptoms. Thus, the duration of depression following stroke is more than six months and the prevalence of major depressive symptoms increases steadily for the first half year after a cerebral hemorrhage or ischemic lesion.

Adult↗
PubMed1984

Elevated sacroiliac joint uptake ratios in systemic lupus erythematosus.

Sacroiliac joint radiographs and radionuclide sacroiliac joint uptake ratios were obtained on 14 patients with active systemic lupus erythematosus. Elevated joint ratios were found unilaterally in two patients and bilaterally in seven patients when their lupus was active. In patients whose disease became quiescent, the uptake ratios returned to normal. Two patients had persistently elevated ratios with continued clinical and laboratory evidence of active lupus. Mild sacroiliac joint sclerosis and erosions were detected on pelvic radiographs in these same two patients. There was no association between low back pain or HLA-B27 positivity and the radiographic or scintigraphic abnormalities. Elevated quantitative sacroiliac joint uptake ratios may occur as a manifestation of active systemic lupus erythematosus.

Adult↗
PubMed1984

Chronic subdural hematoma: surgical management in 133 patients.

One hundred and thirty-three patients with chronic subdural hematoma were treated surgically between 1943 and 1980. The patients, aged 5 to 84 years, were graded retrospectively according to the Bender scale; 28% were in Grades 3 and 4. There were 107 unilateral and 26 bilateral hematomas. The clots were removed mostly via burr-holes without drainage. The treatment of 121 patients included an active policy of brain expansion at operation and the postoperative management of intracranial hypotension by lumbar injection. Two patients died, for a mortality rate of 1.5%. The patients who died were 54 and 59 years old, both from among the 26 cases with bilateral lesions; 107 unilateral lesions were treated, with no deaths. None of 51 patients who were aged 61 years and over died. The mean postoperative stay was 17.2 days, and at 3 weeks 77% had been discharged home. Fifteen percent of survivors had permanent disabilities. The common residual deficits were personality and memory disorders, and there was hemiparesis in Grade 4 cases. The high-risk groups of chronic subdural hematoma were those in Grades 3 and 4, bilateral hematomas, and the elderly. These seemed to be benefited by brain inflation and lumbar injections for intracranial hypotension.

Adolescent↗
PubMed1984

Asymmetrical effects of unilateral cortical suction lesions: behavioral characterization.

Behavioral effects of unilateral frontocortical suction lesions in the right and left hemisphere were characterized by a computerized activity monitoring system. Lesions of the right frontal cortex produced postoperative hyperactivity consisting of increases in the total distance traveled, average distance per movement, and average speed of movement. Vertical, rotational, and stereotypic measures were not changed. Animals receiving left hemisphere lesions did not differ from sham-operated controls on any behavioral variable. The lateralized hyperactivity resulting from lesions of the right frontal cortex was confined to increased length and speed of horizontal movement and did not appear to represent a generalized increase in all components of spontaneous activity.

Animals↗
PubMed1983

JAMA at 100.

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American Medical Association↗
PubMed1983

For authors.

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Periodicals as Topic↗
PubMed1983

A positioning fixture for L-shaped rotating undercutting microknives.

A simple, inexpensive device which controls the insertion, positioning and withdrawal of cortical undercutting microkinives is described. The device aids the "rolling" insertion of an L-shaped microknife which produces a minimum amount of overlying tissue damage while it holds the knife steady during undercutting and allows the blade to be withdrawn by way of the same track through which it was inserted.

Animals↗
PubMed1983

Reliability, validity, and clinical utility of the social functioning exam in the assessment of stroke patients.

Social functioning is an important variable in the rehabilitation of stroke patients. We have designed a 28 item semi-structured interview to measure social functioning and have used this instrument in 103 stroke patients in whom we were investigating the occurrence of mood disorders. The social functioning exam was demonstrated to have high interrater and test-retest reliability as well as good agreement with social functioning as measured by other instruments or clinical assessment. The utility of the measurement of social functioning in the assessment of post-stroke mood disorders was demonstrated by the significant correlation between severity of depression and the degree of dysfunction in social functioning six months after the acute stroke, as well as the significant difference in mean social functioning scores between non-depressed and depressed groups.

Adult↗
PubMed1983

Barrett's esophagus complicating lye ingestion. Demonstration by pertechnetate scintigraphy.

Tc-99m pertechnetate scintigraphy was performed in a patient with Barrett's esophagus and a history of previous lye ingestion. Radionuclide uptake was present in the distal two-thirds of the esophagus and persisted after the drinking of water. This technique is simple and accurate and may be of significant benefit in determining the presence and extent of Barrett's esophagus, which carries an increased incidence of adenocarcinoma development. Examination of patients with chronic gastroesophageal reflux, using this technique, is advocated.

Barrett Esophagus↗