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Biomedical subjects

J Rosen

Publications and source records attributed to J Rosen.

At least 163 records · Page 9Linked to original sources
PubMed1984

Temperature-sensitive mutants of Mycoplasma gallisepticum.

Mycoplasma gallisepticum (MG) S6 strain was treated with nitrosoguanidine to obtain temperature-sensitive mutants. Of the 101 colonies screened, 4 were found to be temperature sensitive. These mutants and the wild type organisms were serologically and morphologically identical. Three of the 4 mutants failed to produce air sac lesions when inoculated directly into air sacs of the chicken.

Animals↗
PubMed1984

Platelet alpha 2-adrenergic receptors in schizophrenic patients before and after phenothiazine treatment.

The specific binding to isolated platelet membranes of 3H-clonidine, an alpha 2-adrenergic receptor partial agonist, and 3H-yohimbine, an alpha 2-adrenergic receptor antagonist, was measured in male, drug-free schizophrenic patients. The maximum number of binding sites (Bmax) for 3H-yohimbine was significantly lower in these patients than in normal subjects. Treatment with chlorpromazine (CPZ) for 2 weeks further decreased the Bmax for both ligands. Plasma catecholamine levels were determined before and after treatment. Before treatment, levels of dopamine and norepinephrine (NE) were within a normal range, while epinephrine (E) levels were significantly elevated. CPZ treatment significantly increased plasma NE levels, but decreased E levels to a normal range. These observations suggest that schizophrenia might be associated with abnormal noradrenergic function that is reflected by a decreased number of platelet alpha 2-adrenergic receptors.

Adult↗
PubMed1984

Evidence for differentiation of right hemisphere visual-perceptual functions.

Performance on tasks sensitive to right hemisphere dysfunction (facial discrimination and perceptual closure) are reported in eight patients with right hemisphere lesions. Patients demonstrated an apparent double dissociation of performance on the two measures. Site-by-task specificity for the closure task was strongly suggested. Implications for right hemisphere organization and underlying psychological processes are considered.

Adult↗
PubMed1984

Free microvascular transfer of second toe ray and serratus anterior muscle for management of thumb loss at the carpometacarpal joint level.

A 50-year-old machine operator suffered traumatic amputation of the thumb, ring, and small fingers. The thumb had been amputated at the carpometacarpal joint and was reconstructed 6 months later by microneurovascular transplantation of the second toe including the second metatarsal. Opposition was provided and the first web space was released at a second stage by reconstruction with the lowest two digitations of the serratus anterior muscle covered with a split-thickness skin graft.

Amputation, Traumatic↗
PubMed1984

Contribution of perceptual motor dysfunction to construction and tracing disturbances in Parkinson's disease.

Patients with Parkinson's disease and controls traced patterns of increasing complexity presented on a vertical transparent screen. Some patterns were presented with missing segments which subjects were required to fill in. Digitising equipment quantitated movements for computer analysis. Subjects also completed a brief test of general intellectual function, a construction test and an assessment for depression, and the severity of patients' Parkinsonian signs and symptoms was rated. Patients performed more poorly than controls on complete patterns, and their errors increased more sharply than controls on patterns with missing segments. Patients' errors, but not those of controls, in filling in missing segments were uniquely related to performance on construction tasks. Other aspects of patients' tracing performance correlated with the severity of their Parkinsonian symptoms. These findings suggest that there is an underlying perceptual motor deficit in Parkinson's disease that affects performance on both tracing and construction tasks.

Aged↗
PubMed1983

Is "subcortical dementia" a recognizable clinical entity?

The concept of "subcortical dementia" is controversial, lacking clinical validation and having only a questionable pathological basis. Over 100 patients with Alzheimer's, Parkinson's or Huntington's disease, subdivided into three functional disability stages, were given a brief quantitative neuropsychological assessment. Patients with Huntington's or Parkinson's disease were less intellectually impaired than those with Alzheimer's disease at each functional stage. Criteria for dementia were present in all of the Alzheimer's patients but in only half of the Huntington's and Parkinson's disease groups. Patients with similar overall intellectual function scores had no distinct pattern of neuropsychological test performance. Depression, absent in patients with Alzheimer's disease, was present in half the patients with Huntington's and Parkinson's disease and was correlated with intellectual decline. The concept of subcortical dementia is misleading. The pattern of neuropsychological impairment is not distinct, and the neuropathological basis of dementia in these diseases may result from a combination of cortical and subcortical degeneration.

Adult↗
PubMed1983

Perceptual motor dysfunction in Parkinson's disease: a deficit in sequential and predictive voluntary movement.

We studied the ability of Parkinsonian patients and controls to generate voluntary movements on a tracing task. Subjects were videotaped while tracing designs of increasing complexity, presented on a vertical, transparent screen. Some designs were presented in a degraded form and subjects filled in their missing sections. Subjects also received a constructional task and a test of general intellectual ability. The quality of errors on the tracing task differed in the Parkinsonian and control groups. Parkinsonian patients made two distinct types of errors. One probably related to the motor disorders of the disease, but another seemed to be related to a higher level of control over sequential and predictive movements. The latter correlated with performance on the constructional and general intellectual tasks. These results suggest that Parkinson's disease may affect basal ganglia structures that are necessary for voluntary movements which require sequencing or planning. Clinically this may be observed in perceptual motor tasks since they require both voluntary movement and sequential organisation of behaviour.

Aged↗
PubMed1982

"Tip-of-the-tongue" phenomenon in Parkinson disease.

Articulatory disturbances are frequently described in Parkinson disease, but language disorders are not. We have occasionally encountered parkinsonian patients with word-finding difficulty unrelated to memory loss, intellectual impairment, or dysarthria. To examine this, 22 medically stable parkinsonian patients were given the vocabulary subtest of the WAIS, the Boston Naming Test, measures of verbal fluency, and sentence repetition. Signs and symptoms of parkinsonism were rated. WAIS vocabulary subtest scores were above the mean for normal aged subjects, but confrontation naming was one standard deviation below norms for age and education. Naming was facilitated by cues in most patients. Only sentence repetition correlated with dysarthria. Category naming was impaired and correlated significantly with the severity of parkinsonism, especially bradykinesia. This suggests that a type of anomia may occur in Parkinson disease. it shares the clinical characteristics of the "tip-of-the-tongue" phenomenon and "word production anomia" seen in some aphasics.

Anomia↗
PubMed1982

Polymer-membrane electrode-based potentiometric sensing of ammonia and carbon dioxide in physiological fluids.

Several new electrochemical devices designed for detecting ammonia and carbon dioxide in physiological samples have in common the elimination of the fragile glass pH internal electrode used in the conventional Severinghaus-design potentiometric gas sensors. In one new approach, the pH glass electrode can be replaced with a neutral carrier-based polymer-membrane pH electrode. Alternatively, to improve response characteristics and selectivity, we have used ion-selective polymer membranes responsive to ammonium and carbonate as internal sensing elements in conjunction with appropriate internal buffer reagents. The use of inner polymer membranes rather than glass membranes enables the fabrication of essentially disposable devices having rapid response times. In addition, we have constructed automated continuous-flow NH3- and CO2-sensing systems involving novel tubular forms of the polymer-membrane electrodes and a simple flow-through gas dialysis arrangement. The polymer electrode-based systems described offer many unique and practical advantages over existing gas-sensing units.

Ammonia↗
PubMed1981

Role of RNA transcripts in replication incompatibility and copy number control in antibiotic resistance plasmid derivatives.

The genes required for autonomous replication and incompatibility in the antibiotic resistance plasmids R100 and R1 have been located within a 2.5-kilobase region of the 90-kilobase genome, within which the incompatibility gene occupies a 1.3-kilobase region excluding the replication origin. We now report that three RNA species are synthesized in vitro from the 2.5-kilobase region, which R100 and R1 have in common. One, a long RNA molecule which is transcribed in the direction of DNA replication, probably acts as a messenger or a protein required for plasmid replication. The second RNA species, only 91 nucleotides long, is transcribed in the opposite direction, from a region of the DNA entirely contained within the first and known to specify incompatibility and copy control functions. The third RNA species, 150 bases long, is transcribed from a region including the replication origin; it may be a primer of DNA synthesis or, in conjunction with the second of the three RNA species, an influence in the control of replication.

Chromosome Mapping↗
PubMed1981

Depression, intellectual impairment, and Parkinson disease.

To determine the prevalence of depression in Parkinson disease (PD) we evaluated 55 consecutive patients without dementia and 31 of their spouses. All subjects completed the Beck depression inventory and a quantitative mini-mental state examination. Using the Beck criteria, 47% of the patients and 12% of the spouses rated themselves as significantly depressed. Mental state scores were significantly lower in the patients. There was a correlation between the severity of depression and cognitive impairment, particularly for calculation, digit span, and visuomotor skills. The severity of parkinsonism, particularly bradykinesia, also paralleled cognition. There was a slight but significant relationship between parkinsonism and depression. These results confirm the high incidence of depression in PD, and suggest that depression in Parkinson patients may be accompanied by mild intellectual impairment and inattention which is independent of the severity of the illness.

Aged↗