Search PubMed⌕ Search

Biomedical subjects

Y Stern

Publications and source records attributed to Y Stern.

At least 217 records · Page 12Linked to original sources
PubMed1993

Regional cerebral blood flow in mood disorders. II. Comparison of major depression and Alzheimer's disease.

We contrasted regional cerebral blood flow in matched groups of 30 patients with major depression, 30 patients with Alzheimer's disease and 30 normal controls using the 133Xe inhalation technique. Whereas both the depressed and Alzheimer's disease groups had markedly reduced global cortical blood flow, the Scaled Subprofile Model, developed to identify abnormalities in regional networks, indicated that they had distinct topographic profiles. Previous findings of an abnormal regional network in major depression were unaltered by the inclusion of Alzheimer's disease patients in the analysis. Alzheimer's disease was associated with a distinct parietotemporal deficit and the degree of this abnormality strongly covaried with cognitive impairment. Alzheimer's disease patients also had abnormal manifestation of three other regional networks. We illustrate a method for distinguishing when a disease imposes a new pattern of interactions among brain regions and when a disease alters the expression of regional patterns characteristic of normal functioning.

Aged↗
PubMed1993

Metastatic malignant melanoma of the tongue.

The tongue is an unusual site for metastases of cutaneous malignant melanoma. A review of the literature revealed only 16 such cases. The discovery of metastases in the tongue usually indicates widespread dissemination of the melanoma and a terminal phase of the disease. Two patients with metastatic malignant melanoma of the tongue are presented. The primary tumors were excised 10 and four years respectively prior to the discovery of the lingual metastases. In one of the patients the lingual metastasis was the first evidence of a disseminated stage of the disease. The histopathological differentiation between primary and secondary melanoma of the tongue is discussed. Such differentiation may have an important therapeutic implication.

Female↗
PubMed1992

A prospective controlled study of magnetic resonance imaging of the brain in gay men and parenteral drug users with human immunodeficiency virus infection.

To detect the earliest structural changes in the brain in human immunodeficiency virus (HIV) infection, 118 gay men and 115 parenteral drug users enrolled in a study of the natural history of HIV infection underwent magnetic resonance imaging evaluations. Routine T2-weighted and heavily T2-weighted scans for quantification of brain water were obtained, blinded to HIV serostatus. Atrophy and foci of increased signal did not correlate with any medical, immunologic, neurologic, or neuropsychologic parameters in the group as a whole, or in the gay men or parenteral drug user subgroups. Three subjects had progressive multifocal leukoencephalopathy and one had central nervous system lymphoma. In a subgroup in whom intracranial water percent was calculated, correlations were found with CD4 counts and CD4/CD8 ratios. We conclude that standard magnetic resonance imaging of the brain does not differentiate asymptomatic and mildly symptomatic HIV-positive individuals from HIV-negative individuals, regardless of risk group. However, intracranial water percent may distinguish HIV-positive from HIV-negative individuals because it correlates with raw CD4 counts and CD4/CD8 ratios.

Adolescent↗
PubMed1992

An estimate of the incidence of depression in idiopathic Parkinson's disease.

Estimates of the prevalence of depression in idiopathic Parkinson's disease vary, but have been greater than in most comparison groups. In a survey of patients with Parkinson's disease (N = 339), the prevalence of depression was 47%. A total of 326 cases were reviewed to estimate the incidence of depression from September 30, 1984, to July 31, 1989. Assessments of depression during both the prevalent and the incident periods were noted in 258 cases. There was no history of depression in 129 cases, and nine new cases occurred. The incidence rate was 1.86% per year and the cumulative risk was 8.6%. Published estimates of the incidence of depression in the general population are few. In one study, the annual incidence of depression in individuals older than 40 years was 0.17%. In another, the incidence of depression in individuals older than 50 years was 0.14% for men and 0.29% for women. Although our retrospective study probably underdiagnoses depression, the incidence of depression is increased in Parkinson's disease.

Aged↗
PubMed1992

The Columbia University Scale for Psychopathology in Alzheimer's disease.

The Columbia University Scale for Psychopathology in Alzheimer's disease is a new screening instrument developed for use by clinicians or trained lay interviewers. Interrater reliability was established between a psychiatrist and a lay interviewer in 20 patients. In an independent sample of 91 outpatients with very mild to moderate probable Alzheimer's disease, caregiver informants reported that depressed mood was common (46.2%) but rarely persistent (2.2%), and that sleep disturbance occurred frequently (41.8%) but was never severe (0%). There were significant but weak associations between the presence of specific subtypes of delusions and severity of dementia. Although a variety of delusional symptoms were reported, they were frequently transient and patients often accepted the truth if corrected by the caregiver. As a result, few patients met broad or narrow operational criteria used to define delusions. Prior studies may have overestimated the prevalence of psychotic features in Alzheimer's disease by not employing standard definitional criteria. The findings also indicate that new methodology such as that employed in this instrument needs to be evaluated more widely.

Aged↗
PubMed1992

Diagnosis of dementia in a heterogeneous population. Development of a neuropsychological paradigm-based diagnosis of dementia and quantified correction for the effects of education.

A brief diagnostic battery of neuropsychological tests was developed for a large-scale epidemiological study of dementia. We operationally defined dementia as defective memory and defective performance in at least two other areas, including orientation, abstract reasoning, construction, and language. Criterion scores for defining defective performance on each test were developed. In a pilot study that used 51 different subjects with a working diagnosis based on physicians' assessment (ie, 32 demented and 29 nondemented subjects), the test-based diagnosis agreed with the working diagnosis in all but two cases. The test battery was then applied to 430 healthy elderly subjects. Eighteen percent of those with 8 or less years of education met criteria for dementia compared with 5% of those with more than 8 years of education. We computed education-corrected scores for each test with the use of residuals from the regression of each test score on education. Based on corrected scores, 12 subjects were reclassified as nondemented and 11 as demented. Subjects who were reclassified as demented were significantly more impaired in activities of daily living than nondemented subjects who were not reclassified. Activities of daily living in subjects who were reclassified as nondemented did not differ from those in demented subjects who were not reclassified. These findings suggest that the neuropsychological battery may have utility in the diagnosis of dementia. However, neuropsychological performance may be influenced by education, and some form of adjustment, such as correction for activities of daily living, may be required in epidemiological studies.

Activities of Daily Living↗
PubMed1992

Diagnosis of dementia in a heterogeneous population. A comparison of paradigm-based diagnosis and physician's diagnosis.

Each of 430 subjects received a diagnosis using two independent methods: a test-based quantitative paradigm and a semistructured neurological examination by a physician. The paradigm diagnosis was based on a battery of tests that assessed short- and long-term verbal memory and short-term nonverbal memory, orientation, construction, abstract reasoning, and language. The subjects came from a community in Manhattan County, in New York City, and were characterized by diversity with respect to both ethnicity (29.1% black, 33.4% Hispanic) and educational level (23.5% with 6 or fewer years of education, 25.6% college educated). Based on the paradigm, 10.5% of subjects received diagnoses of dementia, 29.1% of cognitive impairment, and 60.5% of normal. Based on the physician's diagnosis, 9.8% were demented, 21.6% cognitively impaired, and 68.6% normal. There was agreement between the two diagnostic methods for 71.8% of subjects. Diagnostic disagreement (n = 121) was in most cases between normal and cognitively impaired (71.0%) or between cognitively impaired and demented (21.5%). There were only nine cases (7.5%) in which a subject was judged demented by one method and normal by the other. The reliability of each method with respect to the other was moderate (intraclass correlation coefficient, .62), while the reliability of a composite diagnosis based on both methods was much higher (.77). The paradigm was more likely than the physician to give the diagnosis of dementia to patients with low educational levels. The physician's diagnosis was strongly influenced by measures of functioning and by the mental status test administered in the semistructured neurological examination. Race and diagnosis were not related when the effect of education was controlled.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

A population-based investigation of Parkinson's disease with and without dementia. Relationship to age and gender.

Because the prevalence of idiopathic Parkinson's disease (PD) with or without dementia remains controversial, we initiated a population-based investigation in the Washington Heights-Inwood section of New York, NY, so that nearly complete case ascertainment could be achieved. A "registry" was developed for the study, and we advertised in periodicals and on radio and television. Subjects, or their records, were examined by experienced neurologists, and most underwent a battery of neuropsychological tests specifically designed for assessment in this community. All data were reviewed by a team of clinicians to achieve a consensus diagnosis. The crude prevalence of idiopathic PD, with and without dementia, was 99.4 per 100,000, increasing from 2.3 per 100,000 for those younger than 50 years to 1144.9 per 100,000 for those aged 80 years and older. The crude prevalence for PD with dementia alone was 41.1 per 100,000 and also increased with age from zero for those younger than 50 years to 787.1 per 100,000 for those aged 80 years and older. Prevalence ratios were comparable with those of other published population-based studies in similar settings. After standardization, men had PD with and without dementia more frequently than did women. The major difference between patients with and without dementia was a later estimated age at onset of motor manifestations. We conclude that PD is a frequent disorder in the elderly population that affects men and whites more frequently than women and nonwhites. Moreover, dementia in patients with PD is more frequent than previously recognized and is strongly related to the age at onset of motor manifestations.

Aged↗
PubMed1992

Double-blind parallel design pilot study of acetyl levocarnitine in patients with Alzheimer's disease.

Acetyl levocarnitine hydrochloride has been reported to retard dementia in patients with Alzheimer's disease. In a double-blind, parallel design, placebo-controlled pilot study of 30 mild to moderately demented patients with probable Alzheimer's disease, tests of memory, attention, language, visuospatial, and constructional abilities were administered, and the level of acetyl levocarnitine was measured in the cerebrospinal fluid. Patients were then randomly assigned to receive acetyl levocarnitine hydrochloride (2.5 g/d for 3 months followed by 3 g/d for 3 months) or placebo. After 6 months, the acetyl levocarnitine group demonstrated significantly less deterioration in timed cancellation tasks and Digit Span (forward) and a trend toward less deterioration in a timed verbal fluency task. No differences were found in any other neuropsychological test results. A subgroup with the lowest baseline scores, receiving acetyl levocarnitine, had significantly less deterioration on the verbal memory test and a significant increase in cerebrospinal fluid acetyl levocarnitine levels compared with those receiving placebo. These results suggest that acetyl levocarnitine may retard the deterioration in some cognitive areas in patients with Alzheimer's disease and stress the need for a larger study of this drug.

Acetylcarnitine↗
PubMed1992

Neurologic and neuropsychological manifestations of human immunodeficiency virus infection in intravenous drug users without acquired immunodeficiency syndrome. Relationship to head injury.

We examined 99 human immunodeficiency virus (HIV)-negative and 122 HIV-positive intravenous drug users (IVDUs) without acquired immunodeficiency syndrome (AIDS) to determine whether HIV-positive IVDUs had more neurologic and neuropsychological impairment than their HIV-negative counterparts. Controlling for age, education, drug use, history of head injury, and interactions between head injury and HIV status and drug use, HIV-positive subjects had more extrapyramidal signs and frontal release signs. These findings persisted when asymptomatic HIV-positive subjects without systemic signs of infection and HIV-negative subjects were compared. Neurologic findings were more severe in those with more systemic illness. Among those reporting a history of head injury with loss of consciousness, neuropsychological performance was significantly worse in the HIV-positive subjects, and this increased with severity of illness. This was not true in the group without head injury, suggesting an interaction between history of head injury and the seropositive state. No relationship was noted between head injury and either drug use or HIV state. Therefore, subtle neurologic and neuropsychological abnormalities may precede clinical evidence of AIDS in IVDUs and may be more evident in those with head injury.

Adult↗
PubMed1992

Inverse relationship between education and parietotemporal perfusion deficit in Alzheimer's disease.

A higher prevalence of dementia in individuals with fewer years of education has suggested that education may protect against Alzheimer's disease (AD). We tested whether individuals with more years of education have a more advanced AD before it is clinically evident. As a measure of pathophysiological severity, we quantified regional cerebral blood flow (rCBF), by the 133Xenon inhalation technique; a specific pattern of flow reduction in the parietotemporal cortex corresponds to AD pathology. In 3 groups of patients with probable AD, matched for clinical measures of dementia severity but with varying levels of education, whole-cortex mean flows were comparable. However, the parietotemporal perfusion deficit was significantly greater in the group with the highest level of education, indicating that AD was more advanced in this group. We conclude that education or its covariates or both may provide a reserve that compensates for the neuropathological changes of AD and delays the onset of its clinical manifestations.

Alzheimer Disease↗
PubMed1992

The stability of neuropsychological test performance in a group of parenteral drug users.

The stability of neuropsychological performance in a sample of drug abusers was investigated for a wide range of neuropsychological tests, using a test-retest paradigm with 16 parenteral drug users. The battery administered included tests of general intellectual function, abstract reasoning, verbal memory, language, attention, visuospatial ability, set switching, speeded performance, and manipulative dexterity. Stability coefficients were of a moderate to high magnitude for most of the tests and were comparable to coefficients found in other studies of non-drug-users. Two exceptions, however, were the Selective Reminding Test and the Perdue Pegboard. Possible reasons for instability with these two tests are discussed. It is concluded that neuropsychological investigations of drug abusers can yield consistent and reliable data, although further studies should employ alternative and/or supplementary measures of verbal memory and motor function.

Adult↗
PubMed1992

Event-related potentials (ERPs) during repetition priming in Alzheimer's patients and young and older controls.

Although memory tested explicitly (e.g., recognition) is clearly deficient in the early stages of Alzheimer's disease, it is less clear if memory tested implicitly is similarly affected. To assess this, event-related potentials (ERPs) were recorded during a word-repetition priming paradigm, with semantic and orthographic orienting tasks, from 10 patients with mild probable Alzheimer's disease (PAD; mean age of 70.6), 10 young (24.1) and 10 older (69.8) controls. The extent of priming by word repetition was assessed using the new minus old ERP repetition effect. The young and older control groups showed clear ERP repetition effects that were larger during semantic than orthographic blocks. Although the PAD patients displayed the same general trends, their ERP repetition effects were not nearly as marked when compared to controls. To the extent that the ERP repetition effect recorded during this repetition priming paradigm is a measure of implicit performance, the data suggest that memory assessed in this fashion is spared in at least some Alzheimer's patients in the early stages of the disease.

Adult↗
PubMed1992

Serum prolactin levels in homosexual and bisexual men with HIV infection.

OBJECTIVE: Prolactin is a neurohormone that may be secreted in response to stress and also has regulatory effects on the immune system. Some, but not all, studies suggest that prolactin levels are higher than normal in persons with HIV infection. The authors measured prolactin levels in HIV-positive and HIV-negative homosexual and bisexual men to assess possible differences in levels and then examined relationships between prolactin level and measures of medical status, anxiety, depression, stress, and neuropsychological test performance. METHOD: Blood for prolactin level determination was obtained from 121 HIV-seropositive and 79 HIV-seronegative homosexual and bisexual men enrolled in a longitudinal study. The men also underwent a daylong assessment that included medical, immunological, psychiatric, psychosocial, psychosexual, and neuropsychological evaluations. RESULTS: There was no statistically significant difference in serum prolactin level among the seronegative men, the seropositive men with no or minimal physical symptoms, and the seropositive men with significant physical symptoms of HIV infection. Furthermore, within the HIV-seropositive group, the correlations between serum prolactin level and measures of depression, anxiety, stress, and neuropsychological test performance were all nonsignificant. CONCLUSIONS: Serum prolactin level does not seem to respond to HIV infection or to be related to stress or psychiatric symptoms in HIV-infected men. As none of the subjects had AIDS, the possibility cannot be ruled out that prolactin level increases in very late stages of HIV infection.

Adult↗
PubMed1992

Confusion and memory loss from capsular genu infarction: a thalamocortical disconnection syndrome?

We examined six patients with an abrupt change in behavior after infarction involving the inferior genu of the internal capsule. The acute syndrome featured fluctuating alertness, inattention, memory loss, apathy, abulia, and psychomotor retardation, suggesting frontal lobe dysfunction. Contralateral hemiparesis and dysarthria were generally mild, except when the infarct extended into the posterior limb. Neuropsychological testing in five patients with left-sided infarcts revealed severe verbal memory loss. Additional cognitive deficits consistent with dementia occurred in four patients. A right-sided infarct caused transient impairment in visuospatial memory. Functional brain imaging in three patients showed a focal reduction in hemispheric perfusion most prominent in the ipsilateral inferior and medial frontal cortex. We infer that the capsular genu infarct interrupted the inferior and anterior thalamic peduncles, resulting in functional deactivation of the ipsilateral frontal cortex. These observations suggest that one mechanism for cognitive deterioration from a lacunar infarct is thalamocortical disconnection of white-matter tracts, in some instances leading to "strategic-infarct dementia."

Aged↗
PubMed1992

Dementia after stroke: baseline frequency, risks, and clinical features in a hospitalized cohort.

We determined the frequency of dementia in a cohort of 251 patients aged greater than or equal to 60 years hospitalized with acute ischemic stroke, based on examinations performed 3 months after stroke onset. Using modified DSM-III-R criteria, we found dementia in 66 patients (26.3%). Diagnostic agreement among raters was excellent (kappa = 0.96). In a control sample of 249 stroke-free subjects recruited from the community and matched by age, we found dementia in eight subjects (3.2%). Using a logistic regression model to estimate the risk of dementia associated with stroke in the combined samples, the odds ratio (OR) for stroke patients compared with control subjects was 9.4 (p less than 0.001). Advancing age and fewer years of education were significant, independent correlates of dementia, with a trend evident for race (non-white versus white). Confining the analysis to subjects residing in the Washington Heights-Inwood community of northern Manhattan, the OR was 10.3 (p less than 0.001) with significant age and race effects. We conclude that ischemic stroke significantly increases the risk of dementia, with independent contributions by age, education, and race.

Aged↗