PubMed Health⌕ Search

Biomedical subjects

J Corwin

Publications and source records attributed to J Corwin.

At least 37 records · Page 2Linked to original sources

Early pharmacokinetics and clinical effects of oral D-amphetamine in normal subjects.

Seven normal subjects received 0.25 mg/kg D-amphetamine orally, both after an overnight fast and again after a standard breakfast. Plasma levels, subjective and cardiovascular effects, and observer-rated activation were assessed hourly for 5 hr. Food did not affect amphetamine levels. Plasma levels peaked at 2-3 hr. Maximum cardiovascular effects generally occurred at 1 hr, whereas maximum behavioral and subjective effects occurred at 2 hr. Subjective and behavioral effects declined thereafter, in spite of substantial amphetamine levels. A separate group of 8 subjects received 0.5 mg/kg D-amphetamine orally. Plasma levels, subjective and cardiovascular effects, and activation ratings were assessed hourly for 4 hr. Maximum plasma levels were approximately twice those seen in the first group. In this case, plasma levels peaked at 3-4 hr; blood pressure and subjective and behavioral effects were all maximal at 2-3 hr and were declining by 4 hr, in spite of stable or rising plasma levels.

Administration, Oral↗

Olfaction and hemodialysis: baseline and acute treatment decrements.

The effect of hemodialysis (HD) on olfactory recognition and memory function was investigated in people receiving chronic HD treatment. Fifteen subjects were given an olfactory recognition task 0.5 h before and 0.5 h after a dialysis session in counterbalanced order. Ten dialysis patients received a verbal recall task twice. Ten age-matched normal subjects received the olfactory task twice. Results were: (1) olfactory scores in the HD group were significantly lower than control subjects scores; (2) within the dialysis sample, olfactory identification scores were significantly lower after treatment than before, and (3) there were no parallel decreases in memory performance of the dialysis group after a HD treatment. We therefore conclude that those subjects receiving HD treatment demonstrate acute and chronic deficits in olfactory recognition which are unlikely to be due to fatigue, cognitive disequilibrium, anticoagulant treatment or high levels of uremic toxins.

Adolescent↗

Naltrexone and Alzheimer's disease.

Naltrexone, an oral opiate antagonist, was administered to nine patients with a diagnosis of Alzheimer's-type dementia (ATD) in a two-phase design: an open dose-ranging phase and a double-blind placebo-controlled trial for patients who showed improvement during the open phase. After a three day placebo (baseline) period, patients received increasing doses of naltrexone over two weeks up to a maximum daily dose of 100 mg. Assessments were made at baseline and at daily dose of 5 mg, 50 mg and 100 mg. Testing was done 2 to 4 hours after medication was administered. Any patient who showed cognitive/behavioral improvement on a given dose of naltrexone was then treated with this dosage in a double-blind crossover comparison to placebo. Criteria for inclusion in the double-blind phase consisted of improvement on three behavioral scales and at least one cognitive test on a given dose of naltrexone. Each double-blind phase followed a one-week washout and was two weeks long. Two of the nine patients demonstrated apparent cognitive enhancement on 100 mg daily of naltrexone and were then tested in the double-blind crossover period. Only one of these patients improved during active naltrexone administration. We conclude that the opiate antagonist naltrexone in a dosage range of 5-100 mg daily is not efficacious in ATD.

Alzheimer Disease↗

A controlled assessment of propranolol in the treatment of neuroleptic-induced akathisia.

Twelve patients with neuroleptic-induced akathisia were treated in a randomised, double-blind, cross-over design with propranolol and matching placebo. Propranolol caused significant decrements in both subjective and objective ratings of akathisia, but not in anxiety scores. This confirms prior findings of the efficacy of propranolol in akathisia induced by neuroleptic treatment.

Adult↗

Behavioral effects of phosphatidylserine in the aged Fischer 344 rat: amelioration of passive avoidance deficits without changes in psychomotor task performance.

A series of studies was conducted to evaluate the effects of phosphatidylserine (PS) in aged Fischer 344 rats. No effects were observed in any of four psychomotor tasks in which aged rats normally show deficits, nor on measures of shock sensitivity. However, significant dose-related effects on retention of passive avoidance were observed when PS was given both 30 min prior to training and retention. Further, in a second experiment similar positive effects were observed when PS was given only 30 min prior to training, as well as only 5 min following training. These results suggest that one effect of PS may include an ability to enhance neural events involved in the encoding or consolidation of new information into memory.

Age Factors↗

Efficacy of propranolol in neuroleptic-induced akathesia.

The effects of propranolol, 20 to 30 mg/day, on neuroleptic-induced akathesia were compared with those of lorazepam, 2 mg/day, and periods of no treatment. Raters were blind to treatment condition. As reported in prior open studies, propranolol was found to be dramatically effective in reducing akathesia induced by neuroleptic treatment.

Adult↗

CSF somatostatin in Alzheimer's disease.

Studies have previously demonstrated low somatostatin levels in autopsy cortical tissue from Alzheimer's disease (AD) patients and low somatostatin levels in CSF obtained from subjects with dementia. We evaluated levels of this peptide in 21 non-depressed subjects, 10 with AD, 2 with Parkinson's disease (PD), and 9 with other neurological conditions. The AD patients had significantly lower mean CSF somatostatin than the "other" neurological patients (14.6 +/- 1.5 S.E.M. versus 26.7 +/- 3.2 pg/ml, p less than 0.005). A demented PD subject had a level in the range of the AD group, while the non-demented PD patient had a value above this range. Thus, all 11 patients with AD or PD dementia, analogous disorders, had levels below 21.8 mg/ml, while 7 of the 10 remaining patients had values above 21.8 pg/ml. Age did not explain this finding.

Age Factors↗

Partial improvement in negative schizophrenic symptoms after amphetamine.

In stable schizophrenic outpatients with predominantly "defect state" symptomatology amphetamine caused a reduction in negative symptoms that was statistically significant but not complete (i.e. these symptoms remained clinically discernible). The possibility that dopaminergic hypofunction contributes some elements to the schizophrenic defect state is presented, along with some limited data compatible with this concept. These findings are compared to prior studies in recently hospitalized schizophrenic subjects, and discussed with respect to recent theoretical concepts regarding the role of dopamine in schizophrenic psychopathology.

Adult↗

Solitary plasmacytoma of bone vs. extramedullary plasmacytoma and their relationship to multiple myeloma.

Solitary plasmacytoma of bone (SPB) and extramedullary plasmacytoma (EMPC) are unusual solitary tumors of plasma cell origin. The clinical differences between these tumors and multiple myeloma are the subject of continued study. This review examines the radiotherapy experience at M. D. Anderson Hospital. Between 1948 and 1977, 12 patients with SPB and 12 patients with EMPC were treated with radiotherapy. Radiotherapeutic doses were most often (22/24) greater than 4,000 rads, at 200 rads per day. In order to qualify as solitary plasmacytoma a disease-free interval of 3 years was required. In the group of SPB, 5 patients of 9 were alive with no evidence of disease (NED) at 3 years, 4 of 5 at 5 years, and none of 4 at 10 years. In the EMPC group, 8 patients of 11 were NED at 3 and 5 years, and 6 of 9 at 10 years. Six patients with SPB developed multiple myeloma compared with only two with EMPC. The results confirm the better prognosis of EMPC and support the theory that SPB and EMPC are two different entities.

Adolescent↗