Biomedical subjects

M Lichtenstein

Publications and source records attributed to M Lichtenstein.

At least 19 recordsLinked to original sources

PubMed2001

Distal infantile neuroaxonal dystrophy--a new familial variant with perineuronal argyrophilic bodies.

We report on two sisters with an infantile onset of dyskinetic movements, tonic spasms, seizures and apneic spells. The condition deteriorated to a hypotonic "burnt out" stage by the age of 3 years in the older sister and to a stable dyskinetic condition by the age of 2.5 years in the younger one. A skin biopsy from the older sister revealed myelinated nerve fibers crowded with neurofilaments. The extensive investigation for neurometabolic disorder, magnetic resonance imaging of the brain, and ophthalmological and neurophysiological examinations were not especially revealing. The older sister died at the age of 3 years. The autopsy revealed no apparent loss of nerve cells in the brain and no sign of storage disease. However, silver-stained coarse granules, immunopositive for neurofilament polypeptide, were found around nerve cell bodies in the cortex and in the basal ganglia. Electron microscopy revealed perineuronal membrane-bound profiles filled with filaments. Silver-stained axonal torpedoes were found in the cerebellum, but there were no spheroids. The substantia nigra, the locus ceruleus and the nucleus basalis of Meynert showed extensive perineuronal and perivascular swelling. Homovanillic acid was severely reduced, while 5-hydroxyindoleacetic acid and hydroxymethylphenyl glycol were normal in the cerebrospinal fluid of the severely affected, autopsied case. The two cases are considered to represent a new form of infantile neuroaxonal dystrophy, characterized by the degeneration of perineuronal terminals in the cerebral cortex and in the basal ganglia, as well as by axonal degeneration in the cerebellum and peripheral nerves.

Brain↗

PubMed2001

Combined magnetic resonance imaging and single-photon emission tomography scanning in the discrimination of Alzheimer's disease from age-matched controls.

OBJECTIVE: To compare the utility of temporal lobe magnetic resonance imaging (MRI) and single-photon emission tomography (SPET) scanning in discriminating between subjects with Alzheimer's disease (AD) and age-matched controls. METHODS: Thirty subjects with NINCDS-ADRDA AD (23 probable AD, 5 possible AD, 2 definite AD) and 22 age- and sex-matched controls underwent T1-weighted coronal MRI scanning (0.3 T) and technetium 99m-HMPAO SPET scanning. MRI scans were analyzed using a digitizer system with volumes of hippocampus, amygdala, entorhinal cortex, parahippocampal gyrus, and whole cerebral cortex calculated. From SPET scans, regional cerebral blood flow (rCBF) was assessed in anterior and posterior frontal, parietal, occipital, and mesial temporal cortex using a region of interest analysis with the cerebellum as a reference area. RESULTS: Using MRI, the areas that best separated groups were left hippocampal and left amygdala volume, resulting in correct classification (patient vs. control) in 79% of cases (sensitivity 77%, specificity 82%). Exactly the same proportion of subjects were correctly classified by SPET, with the most discriminating rCBF changes being left parietal and right posterior frontal. Combining information from both scans improved the proportion of correctly classified subjects in a discriminant function to 90% (sensitivity 93%, specificity 86%; only 2 AD and 3 controls misclassified). All AD subjects had abnormalities on MRI and/or SPET (sensitivity for combined examinations 100%), while abnormalities on both MRI and SPET had a positive predictive value of 100% for dementia (including the detection of one control subject who later had dementia). Significant correlations between MRI and SPET measures were seen in control subjects but not in patients. CONCLUSION: Both 0.3 T MRI and single rotating gamma camera SPET were equally useful in separating AD subjects from age-matched controls, although the combination of both significantly enhanced discrimination. In particular, all AD subjects had abnormalities on either MRI or SPET and both techniques may have an important role in assisting with clinical diagnosis, though replication in other centers and examination of differentiation of AD from other causes of dementia need to be examined.

Aged↗

PubMed2001

Control of nuclear export of hnRNP A1.

mRNA export is mediated by RNA-binding proteins which shuttle between the nucleus and cytoplasm. Using an in vitro unidirectional export assay, we observe that the shuttling mRNA-binding protein, hnRNP A1, is exported only extremely slowly unless incubations are supplemented with snRNA-specific oligonucleotides which inhibit splicing. In vivo microinjection experiments support this conclusion. Like many examples of nucleocytoplasmic transport, export of hnRNP A1 requires energy and is sensitive to the presence of wheat germ agglutinin. It does not, however, require supplementation with cytoplasmic proteins. Although the exportin, Crm1, is needed for export of several varieties of RNA, both the in vitro assay and in vivo assays show that it is not required for export of hnRNP A1. In vitro and in vivo studies also show that inhibition of transcription allows continued shuttling of hnRNP A1 and in fact accelerates its export. Judging from the stimulatory effects of targeted destruction of snRNAs, this is likely to reflect completion of the covalent maturation of the RNAs with which hnRNP A1 associates. These observations therefore provide a simple explanation of why multiple RNA-binding proteins relocate to the cytoplasm upon inhibition of transcription in vivo.

Active Transport, Cell Nucleus↗

PubMed2001

Lower body function and mortality in Mexican American elderly people.

BACKGROUND: The purpose of this analysis was to examine the differential impact of performance-based and self-reported lower body measures on 2-year mortality in Mexican American elderly persons. METHODS: Data employed are from the Hispanic Established Population for Epidemiological Studies of the Elderly, a probability survey of 3050 community-dwelling Mexican Americans aged 65 and older from the five Southwestern states interviewed in 1993 and 1994. Of the baseline sample with complete data, 198 persons were confirmed deceased 2 years later. A three-task, performance-based, lower body function measure consisting of a short walk, balance, and repeated chair stands tests was used. Self-reported lower body function was measured by a 4-item Activities of Daily Living (ADL) measure involving the lower body. RESULTS: The three-task, lower body function measure was a significant predictor of 2-year mortality. The short walk alone was as predictive as the summary measure. The predictive ability of both measures was minimally reduced by the inclusion of the self-reported ADL measure and life-threatening medical conditions. Finally, the ADL measure was not a significant predictor of mortality with all the other variables in the analysis. CONCLUSION: Objective measures of lower body function were significant predicators of mortality in Mexican American elderly persons, as found in the general population. Unlike previous studies, the ADL measure was not an independent predictor of mortality after controlling for the objective measure and other risk factors. Additional research is needed to address why objective measures of function are such strong predictors of death.

Activities of Daily Living↗

PubMed2001

Comparison of MRI perfusion imaging and single photon emission computed tomography in chronic stroke.

There have been few direct comparisons between MR perfusion-weighted imaging (PWI) and established perfusion imaging techniques, and none in chronic stroke. We therefore studied 17 chronic hemispheric infarction patients (mean, 90 days) and compared hypoperfusion volumes determined from PWI maps of relative cerebral blood flow (rCBF) and volume (rCBV), and mean transit time (rMTT) with those measured with (99)Tc-HMPAO single photon emission computed tomography (SPECT). Comparisons were also made between infarct size (T(2)-WI) and clinical scales. Correlations were found between lesion location and volume in all three PWI hemodynamic parameter maps with clinical state and lesions on SPECT and T(2)-WI. In 3 patients, rCBF and rCBV lesions extended well beyond the borders of moderate-sized infarctions. We conclude that in chronic stroke, PWI can delineate regions of abnormal perfusion that reflect the degree of functional impairment and structural damage. The finding of peri-infarct hypoperfusion suggests that PWI may have the potential to provide a rapid and non-invasive template against which interventional strategies aimed at promoting functional recovery may be investigated.

Aged↗

PubMed2000

Review: dynamic stability of the interphase nucleus in health and disease.

Ongoing export of newly synthesized RNAs, as well as control of transcriptional activity, involves dynamic nucleocytoplasmic transport of proteins. Some proteins that shuttle reside primarily in the nucleus while others are concentrated in the cytoplasm. Moreover, some proteins shuttle continuously, while others shuttle only once. A third group is stimulated to relocate either into or out of the nucleus as a result of interruption of shuttling. In addition to these protein-specific events, several physiological stimuli have global effects on nucleocytoplasmic transport. In related events, selected proteins move between distinct sites in the nucleoplasm, others enter and leave the nucleolus, and still others transit between the nuclear envelope and cytoplasmic membranes. These multiple dynamic distributions provide numerous opportunities for precise communication between spatially distant sites in the cell.

Animals↗

PubMed2000

Hearing problems in Mexican American elderly.

OBJECTIVE: To investigate hearing problems in a sample of elderly Mexican Americans. STUDY DESIGN: A longitudinal field study of a cohort of 3,050 subjects with in-person baseline and a 2-year follow-up. Population-based, cross-sectional, weighted data were analyzed. SETTINGS AND SUBJECTS: Hispanic Established Populations for Epidemiologic Studies of the Elderly (H-EPESE) consisting of Mexican Americans aged 65 and older provided basic health data using area probability sampling in five southwestern states during 1993 and 1994. MAIN OUTCOME MEASURES: Information was collected regarding demographics, medical conditions, smoking, and alcohol consumption. Hearing problems were identified through a series of self-perceived hearing problem questions, hearing aid use, and inability to hear a normal voice. RESULTS: A hearing problem was identified in 24.5% of this cohort (weighted, 748/3,049). Statistical analysis using a multiple logistic regression model was performed to identify factors jointly associated with hearing problems. Age group (odds ratio [OR] = 2.7, p<0.0001), male sex (OR = 1.9, p< 0.0001), hypertension (OR = 1.4, p<0.001), arthritis (OR = 1.5, p<0.0005), significant depressive symptomatology (OR = 1.4, p<0.002), and ever having consumed alcohol (OR = 1.4, p<0.005) were jointly statistically significantly associated with hearing problems. Number of cigarettes smoked daily (e.g., 0, 1-10, 11-20, etc.) was nearly significantly associated with a hearing problem in the multivariate model (OR = 1.1 for each increased in category, p<0.07). CONCLUSIONS: Hearing problems are common in this population. Control of hypertension, an amelioration of arthritis, and decreasing the consumption of alcohol and cigarettes may lower the likelihood of development of a hearing problem. Initial depressive symptomatology may have occurred subsequent to the hearing loss. A longitudinal study would allow determination of the direction of causation.

Aged↗

PubMed2000

High incidence of micrometastases in breast cancer sentinel nodes.

BACKGROUND: Sentinel lymph node biopsy (SLNB) is being investigated as an alternative to formal axillary dissection in early breast cancer. Avoiding the morbidity of unnecessary axillary dissection is seen as the main potential benefit of SLNB. Sentinel lymph node biopsy also allows enhanced pathological analysis. A series of 62 sentinel node (SN) biopsies demonstrating a high incidence of micrometastases is presented here. METHODS: All SN were initially examined and reported by H&E staining. All negative SN were analysed after staining with polyclonal anticytokeratin antibody. RESULTS: Sixty-two patients underwent SLNB at Royal Melbourne Hospital between May 1998 and February 2000. One or more SN was identified in 51/62 patients. A total of 10/51 contained metastases identified after H&E staining. There was one false negative. A total of 10/41 patients with H&E-negative SN had micrometastases identified on immunohistochemistry (IHC). Micrometastases were more common in patients with larger tumours, with disease found in the H&E-negative SN of 1/17 T1a and T1b (1-10 mm), 4/15 T1c (11-20 mm), and 5/9 T2 (20-50 mm) tumours. CONCLUSION: Sentinel lymph node biopsy can accurately assess the axilla in most patients with early breast cancer. A significant proportion of histologically negative SN will have micrometastases identifiable with IHC. Although the clinical significance of such metastases is uncertain, the available evidence suggests that these patients have a poorer prognosis than other patients with negative lymph nodes.

Adult↗

PubMed1999

Efficacy of high-dose glycine in the treatment of enduring negative symptoms of schizophrenia.

BACKGROUND: Disturbances of N-methyl-D-aspartate (NMDA) receptor-mediated glutamatergic neurotransmission may play an important role in the pathophysiology of negative symptoms of schizophrenia. Glycine, a small nonessential amino acid, functions as an obligatory coagonist at NMDA receptors through its action at a strychnine-insensitive binding site on the NMDA receptor complex. Glycine-induced augmentation of NMDA receptor-mediated neurotransmission may thus offer a potentially safe and feasible approach for ameliorating persistent negative symptoms of schizophrenia. METHODS: Twenty-two treatment-resistant schizophrenic patients participated in a double-blind, placebo-controlled, 6-week, crossover treatment trial with 0.8 g/kg per day of glycine added to their ongoing antipsychotic medication. Clinical assessments, including the Brief Psychiatric Rating Scale (BPRS), the Positive and Negative Syndrome Scale (PANSS), the Simpson-Angus Scale for Extrapyramidal Symptoms, and the Abnormal Involuntary Movement Scale, were performed biweekly throughout the study. Clinical laboratory values and amino acid serum levels were monitored. RESULTS: Glycine treatment was well tolerated and induced increased glycine (P=.001) and serine (P=.001) serum levels. Glycine administration resulted in (1) a significant (P<.001) 30%+/-16% reduction in negative symptoms, as measured by the PANSS, and (2) a significant (P<.001) 30%+/-18% improvement in the BPRS total scores. The improvement in negative symptoms was unrelated to alterations in extrapyramidal effects or symptoms of depression. Low pretreatment glycine serum levels significantly predicted (r= 0.80) clinical response. CONCLUSION: These findings support hypoglutamatergic hypotheses of schizophrenia and suggest a novel approach for the pharmacotherapy of negative symptoms associated with this illness.

Adult↗

PubMed1999

Treatment-resistant schizophrenia and staff rejection.

This study examined the relationship between characteristics of patients suffering from treatment-refractory schizophrenia and staff rejection and criticism. Subjects were 30 inpatients with treatment-resistant schizophrenia and the 29 staff members treating them. Measures included assessment of the patients' symptoms and aggression risk profile using the Positive and Negative Syndrome Scale (PANSS) and assessment of staff attitudes toward these patients using the Patient Rejection Scale (PRS). Nursing staff completed the Nurses' Observation Scale for Inpatient Evaluation (NOSIE). PRS ratings did not correlate with patients' demographic and treatment characteristics. Significant correlations existed, however, between increased staff rejection and higher scores for PANSS cognitive factor and NOSIE manifest psychosis factor. Negative symptoms, although preponderant in the patient sample, were not significant predictors of staff rejection on the PRS. Older nursing staff tended to view patients as more irritable and manifestly psychotic. These findings suggest that disorganized behavior and impaired cognition dysfunction areas are more likely to be associated with high levels of rejection among staff working with treatment-resistant schizophrenia patients. Incorporation of the relatively new concepts of cognitive dysfunction and treatment resistance in staff training programs and multidisciplinary team reviews may greatly benefit schizophrenia patients and the staff treating them.

Adult↗

PubMed1999

Nimodipine and perfusion changes after stroke.

BACKGROUND AND PURPOSE: Meta-analysis of previous trials of oral nimodipine in acute stroke has suggested a benefit when commenced within 12 hours of onset. We sought to study the effect of oral nimodipine on reperfusion after acute stroke and the relation between reperfusion and outcome. METHODS: Fifty patients with acute middle cerebral artery territory cortical infarction were blindly randomized within 12 hours of onset to either oral nimodipine (30 mg every 6 hours) or placebo. Treatment was continued for 2 weeks. Cerebral blood flow was assessed with the use of 99mTc-hexamethylpropyleneamine oxime single-photon emission CT before therapy, 24 hours later, and at 3 months. Hypoperfusion was measured by a validated volumetric technique. Neurological impairment and functional outcome were assessed with the Canadian Neurological Scale and Barthel Index, respectively. Tissue loss was measured with CT at 3 months. Four patients were excluded from analysis for technical reasons. RESULTS: Twenty-three patients received nimodipine, and 23 received placebo. In the nimodipine group, there was early reperfusion that was not maintained at outcome (P=0.01). In the placebo group, mean infarct hypoperfusion volumes showed no overall change. Nonnutritional reperfusion in nimodipine-treated patients was associated with adverse neurological (P=0.05) and functional outcome (P=0.06). There was, however, no difference in clinical outcome between the 2 groups. CONCLUSIONS: Oral nimodipine administered within 12 hours enhanced acute reperfusion, but this was largely nonnutritional. Larger studies using a shorter treatment delay are required to evaluate the clinical efficacy of nimodipine in acute ischemic stroke.

Acute Disease↗

PubMed1998

Congenital toxoplasma gondii infection diagnosed by PCR amplification of peripheral mononuclear blood cells from a child and mother.

A case of congenital toxoplasmosis is presented, where diagnosis by PCR amplification of Toxoplasma gondii DNA from peripheral blood led to early treatment of the infant and seemingly normal brain development despite the presence of intracranial calcifications at birth. The mother, who experienced a subclinical infection during pregnancy, was PCR-positive for toxoplasma DNA in a sample of peripheral blood drawn after delivery.

Animals↗

PubMed1998

Spontaneous reperfusion after ischemic stroke is associated with improved outcome.

BACKGROUND AND PURPOSE: The rationale behind thrombolytic therapy in acute ischemic stroke is penumbral salvage by rapid restoration of cerebral blood flow. The relationship, however, between early reperfusion (potentially composed of both nutritional and nonnutritional components) and outcome remains unclear. METHODS: To establish the relationship between reperfusion parameters and outcome variables (Canadian Neurological Scale, Barthel Index, outcome CT scans), we used 99Tc-hexamethylpropyleneamine oxime (99Tc-HMPAO) single-photon emission CT (SPECT) to examine 41 acute ischemic stroke patients. All patients had at least 2 SPECT studies (24 with 3 studies), and none had been treated with thrombolytic or other acute investigational drugs. RESULTS: A total of 106 studies were performed. Mean time to acute study was 9.2 hours; that for subacute study was 42 hours and for outcome study was 150 days. Hypoperfusion (HP) volumes at each of the 3 time points correlated with outcome clinical state and final infarct size. Both early reperfusion (61% of patients) and nutritional reperfusion alone (56%), which is early reperfusion maintained at outcome, were associated with improvement in clinical state and better functional outcome. Early HP volume change (acute minus subacute HP volume) and total HP volume change (acute minus outcome HP volume) also correlated with clinical improvement and better outcome. CONCLUSIONS: This study establishes the benefit of spontaneous reperfusion after ischemic stroke and emphasizes the prognostic value of HP deficit volumes. 99Tc-HMPAO SPECT may be used to screen patients and group them according to perfusion deficit in acute stroke trials, thereby decreasing patient numbers required to show drug effect.

Adult↗

PubMed1998

Impact of selected medical conditions on self-reported lower-extremity function in Mexican-American elderly.

OBJECTIVE: To examine the independent impact of common medical conditions on lower-extremity function in Mexican-American elderly. DESIGN: Cross-sectional study using a probability sample of non-institutionalized Mexican Americans aged 65 or older. SETTING: The five Southwestern states, Texas, New Mexico, Arizona, Colorado and California. PARTICIPANTS: All subjects were interviewed in person (n = 2,873) or by proxy (n = 177) in their homes during late 1993 and early 1994. MAIN OUTCOME MEASURES: Respondents were asked whether they could perform four activities related to lower-extremity function without help: walking across a small room, getting from a bed to a chair, walking up and down stairs, and walking half a mile. A summary measure of lower body disability created from these four items was regressed on seven common medical conditions plus five control variables using multiple logistic regression. RESULTS: Adjusted Odds Ratios (OR) suggested that impaired lower-extremity function was associated with previous diagnosis of hip fracture (OR = 4.28), stroke (OR = 3.47), lower extremity arthritis (OR = 2.60), heart attack (OR = 2.29), diabetes (OR = 2.03) and obesity (OR = 1.50). Impaired lower-extremity function was significantly associated with older age (75+ years old), gender (female) and marital status (unmarried). In addition, there was a linear increase in the risk of function loss by number of medical conditions. CONCLUSIONS: It appears that Mexican-American elderly diagnosed with medical conditions, especially stroke and hip fracture, have a high risk for lower-extremity dysfunction. These findings have implications for efforts to prevent or reduce lower-extremity dysfunction, as well as for the provision of community-based long-term care services for Mexican-American elderly.

Activities of Daily Living↗

PubMed1997

Cytokine mRNA in Gaucher disease.

Gaucher disease, the most common glycolipid storage disease, is caused by glucocerebrosidase deficiency, resulting in accumulation of glucocerebrosides within the macrophages of the reticuloendothelial system. The disease is characterized by great phenotypic heterogeneity, which can be explained only in part by the various mutations in the glucocerebrosidase gene, and by the amount of storage material in affected organs and tissues. Therefore, it has been postulated that some of the biochemical and clinical features may be related to the fact that "Gaucher" cells, as activated macrophages, express and release cytokines such as IL-1beta, IL-8, IL-6 and TNF-alpha which play a role in different physiological processes. In the present study, cytokine mRNA expression was measured in monocytes isolated from Gaucher patients and from healthy controls, using RT-PCR methodology with semiquantitative analysis. We found significantly increased expression of IL-1beta mRNA, as well as a trend to elevated TNF-alpha mRNA in Gaucher patients relative to healthy individuals. There were no statistically significant differences between Gaucher disease patients and controls with respect to two other tested cytokines (IL-6 and IL-8).

Adult↗

PubMed1997

Nandrolone decanoate and intranasal calcitonin as therapy in established osteoporosis.

This study used a randomized, 2 x 2 factorial design to evaluate over 2 years the effect of intranasal salmon calcitonin and intramuscular nandrolone decanoate on bone mass in elderly women with established osteoporosis. The study was double masked in relation to calcitonin and open in relation to nandrolone decanoate. One hundred and twenty-three women aged 60-88 years who had sustained a previous osteoporotic fracture, or had osteopenia, were recruited through an outpatient clinic. Women were assigned to one of four groups: (1) daily placebo nasal spray, (2) 400 IU intranasal calcitonin daily, (3) 20 intramuscular injections of 50 mg nandrolone decanoate (given as two courses of 10 injections) plus placebo nasal spray, or (4) 20 injections of 50 mg nandrolone decanoate plus 400 IU intranasal calcitonin daily. All subjects received 1000 mg calcium supplementation daily. Outcomes measured included changes in bone mineral density (BMD) at the lumbar spine, as measured by dual-energy quantitative computed tomography (DEQCT), in BMD of the proximal femur, and BMD and bone mineral content (BMC) of the lumbar spine and forearm, as measured by dual-energy X-ray absorptiometry (DXA). Significant positive changes from baseline in DXA BMC at the lumbar spine were observed over 2 years in the calcitonin group (5.0 +/- 1.9%, mean +/- SE) and in the nandrolone deconate group (4.7 +/- 1.9%) but not in the placebo group (1.1 +/- 2.2%) or the combined therapy group (0.7 +/- 1.8%). Modelling based on the 2 x 2 factorial design revealed that nandrolone decanoate was associated with a 3.8 +/- 1.8% (p < 0.05) gain in DXA BMD at the proximal femur. Modelling also revealed that calcitonin treatment was associated with a loss of 11.5 +/- 4.7% in DEQCT BMD at the lumbar spine and a loss of 3.7 +/- 1.8% in DXA BMD at the proximal femur (p < 0.05). There was in vivo antagonism between the two medications of 7.9 +/- 3.9% for DXA BMC at the lumbar spine. Both agents caused positive changes from baseline in lumbar spine BMC. Nandrolone decanoate had beneficial effects on BMD at the proximal femur. This dose of intranasal calcitonin was associated with deleterious effects on trabecular BMD at the lumbar spine and total BMD at the proximal femur. There may be significant clinical antagonism between these two medications.

Administration, Intranasal↗

PubMed1997

Volumetric analysis of cerebral hypoperfusion on SPECT: validation and reliability.

UNLABELLED: A method of volumetric analysis of hypoperfusion on 99mTc-labeled hexamethylpropylene amine oxime SPECT has been developed. This analysis integrates both the size and severity of perfusion reduction, yielding an equivalent volume of cortical tissue having zero blood flow, or the effective hypoperfusion volume. This study aimed to validate the methodology in vitro using the Hoffman brain phantom and two different camera systems, to examine the relationship between spatial resolution and accuracy of volume measurement and to assess the interobserver variability in SPECT studies of stroke patients. METHODS: Simulated cortical lesions of three different sizes were sequentially incorporated into the Hoffman brain phantom and imaged using both single- and triple-head camera systems. For each system and for each lesion size, successive acquisitions were performed using three progressively larger radii of camera rotation. The hypoperfusion volume for each study was measured three times by a blinded observer, and the percentage difference from the true lesion volume was then calculated. SPECT studies of 32 stroke patients were independently analyzed by two blinded observers. RESULTS: At the smallest radii of rotation, mean (s.d.) percentage difference between observed and true volumes was 0.90% (4.80%) for the triple-head and 4.50% (11.58%) for the single-head system. The degree of overestimation was similar for both systems. Percentage overestimation was strongly associated with radius of rotation (B = 0.71 +/- 0.32, p = 0.04 for the triple-head system; B = 1.26 +/- 0.55, p = 0.03 for the single-head system) but not with lesion size. The mean difference between hypoperfusion volumes of stroke patients obtained by two observers was 0.045 (3.240) cm3, which was not significant. CONCLUSION: This study has shown that this technique of volumetric analysis of regional hypoperfusion on SPECT is both highly accurate and reproducible between two different camera systems. The degree of overestimation chiefly relates to diminishing spatial resolution. Despite some element of subjectivity, the interobserver variability is negligible.

Animals↗

PubMed1996

The effect of medical conditions on the functional limitations of Mexican-American elderly.

We examined the relationship of self-reported functional status to common medical conditions using a probability sample of 3050 noninstitutionalized Mexican-American men and women aged 65 or older and residing in the Southwestern United States (Arizona, California, Colorado, New Mexico, and Texas). All subjects were interviewed in person (n = 2,873) or by proxy (n = 177) in their homes during late 1993 and early 1994. The questionnaire obtained information on self-reported functional status and prevalence of arthritis, cancer, diabetes, stroke, heart attack, and hip fracture. The prevalence of medical conditions ranged from 4.1% for hip fracture to 40.8% for arthritis. Prevalence of impairments in seven activities of daily living ranged from 5.4% for eating to 11.7% for bathing, while 25.1% could not walk up and down stairs, and 28.9% could not walk a half mile without help. In multiple logistic regression analyses, previous diagnoses of stroke and hip fracture were most predictive of functional limitations, though all conditions examined (arthritis, cancer, diabetes, stroke, heart attack, and hip fracture) were independently associated with increased odds of impairment in some activities of daily living. In general, the odds for functional impairment associated with specific medical conditions were higher than those previously published for non-Hispanic white populations. The fact that Mexican-American elderly who live in the community and who have medical conditions, especially stroke and hip fracture, are at high risk for functional impairment probably reflects the low rate of institutionalization in this population and has implications for the provision of community-based long-term care services for Mexican-American elderly.

Activities of Daily Living↗