Longitudinal association of vascular and Alzheimer's dementias, diabetes, and glucose tolerance

OBJECTIVE

To assess the relationship between impaired glucose tolerance and both vascular dementia and AD.

BACKGROUND

Diabetes and abnormalities of glucose metabolism have been associated with stroke and poor cognitive function. In addition, glycoproteins and glycosylation have been postulated to be associated with the development of neuritic plaques characteristic of AD.

METHODS

A historical prospective cohort study of Japanese-American men (n = 3,774), who were examined at ages 45 to 68 (1965 through 1968) and again at ages 71 to 93 (1991 through 1993). Measurements were obtained by clinical and home examinations: assessment of glucose intolerance (nonfasting 1 hour after glucose load) from 1965 through 1968 and history of diabetes diagnosed by a physician at examinations given from 1965 through 1968 and from 1976 through 1978. At the 1991 through 1993 examinations, the Cognitive Assessment Screening Instrument (CASI)-an instrument designed for use in cross-cultural settings combining features of the Folstein Mini-Mental State Examination, the Modified Mini-Mental State Examination, and the Hasegawa Dementia Screening Scale-was used. Diagnosis and classification of AD and vascular dementia were made by a consensus panel using neuropsychologic assessment data, a neurologist's evaluation, and information from a family informant. Diagnostic and Statistical Manual of Mental Disorders, 3rd ed., revised criteria were used to establish dementia, and subclassification by cause was based on other published criteria.

RESULTS

No association between AD and diabetes, present either 25 or 15 years previously, was found after adjustment for age and education in a multiple regression model. A significant association was found between impaired glucose tolerance at baseline and vascular dementia (p < 0.01).

CONCLUSIONS

These findings confirm expected relationships between impaired glucose tolerance and stroke-related dementia but do not support an association of disordered glucose metabolism with AD.

Wavelength-tunable high-power picosecond pulses from a fiber-pumped diode-seeded high-gain parametric amplifier

We describe a high-gain optical parametric amplifier (OPA) and optical parametric generator (OPG) system pumped by a fiber chirped-pulse amplification source based on novel large-mode-area fiber components. 45-nJ OPG thresholds and 34% pump-signal conversion efficiencies are obtained for ~4-ps pulses. OPA gains in excess of 75 dB and pump-signal conversion efficiencies of ~39% (external) are demonstrated. Furthermore, we show that injection seeding of such high-gain parametric devices by use of a low-power continuous-wave beam results in high-power (>18-kW) picosecond pulses with a time-bandwidth produce of ~0.65, some ten times less than from a free-running OPG. Using such an approach, we obtain 2.7-ps 50-nJ pulses at 1.310 mum .

Height as a marker of childhood development and late-life cognitive function: the Honolulu-Asia Aging Study

OBJECTIVE

Growing evidence suggests that structural and functional brain reserves, thought to develop in childhood and adolescence, may be crucial in determining when cognitive impairment begins. The purpose of this report is to examine the relationship of height, as a marker of childhood development, to late-life cognitive function in a sample of elderly Japanese-American men.

METHOD

Cognitive performance was assessed from 1991 to 1993 in the Honolulu-Asia Aging Study in 3733 men aged 71 to 93 years and related to height that was measured 25 years earlier.

RESULTS

Among the study sample, shorter men were older, leaner, and less educated than taller men. Shorter men also spent more years of their childhood living in Japan and were more likely to have had fathers in unskilled professions. After adjustment for age, the prevalence of poor cognitive performance declined consistently with increasing height from 25% in men shorter than 154 cm (61 in) to 9% in those taller than 174 cm (69 in). Excluding men with stroke or dementia did not alter the association between height and cognitive performance. Apolipoprotein E4 was unrelated to height and did not effect the association between height and cognitive function. The prevalence of Alzheimer's disease was higher in men who were 154 cm (61 in) or shorter as compared with men who were taller (4.7% vs 2.9%, respectively). There was no association between height and vascular dementia.

CONCLUSION

Efforts to improve prenatal and early life conditions to maximize growth in childhood and adolescence could diminish or delay the expression of cognitive impairments that occur later in life. Prevention of some late-life cognitive impairments may have pediatric origins.

Coffee consumption in hypertensive men in older middle-age and the risk of stroke: the Honolulu Heart Program

OBJECTIVE

To examine the association between coffee consumption and the development of stroke in men at high risk for cardiovascular disease.

METHODS

Coffee intake was observed from 1965 to 1968 in a cohort of men enrolled in the Honolulu Heart Program with follow-up for incident stroke over a 25-year period. Subjects were 499 hypertensive men (having systolic or diastolic blood pressures at or above 140 and 90 mm Hg, respectively) in older middle-age (55 to 68 years) when follow-up began. Past and current cigarette smokers were excluded from follow-up.

RESULTS

In the course of follow-up, 76 men developed a stroke. After age-adjustment, risk of thromboembolic stroke increased significantly with increases in coffee consumption (P = 0.002). No relationships were observed with hemorrhagic stroke. When adjusted for other factors, the risk of thromboembolic stroke was more than doubled for men who consumed three cups of coffee per day as compared to nondrinkers of coffee (RR = 2.1; 95% CI = 1.2-3.7).

CONCLUSIONS

Although in need of further confirmation, consumption of coffee appears to be positively associated with an increased risk of thromboembolic stroke in hypertensive men in older middle-age. Findings suggest that it may be prudent to advise older middle-aged men with hypertension who consume large amounts of coffee to consider reducing their coffee intake.

Influence of myocardial infarction, coronary artery bypass surgery, and stroke on cognitive impairment in late life

Relations between cognitive test scores in later life and prior myocardial infarction (MI), coronary artery bypass graft surgery (CABG), and stroke were examined for this study. Subjects were 3,734 Japanese-American men (80% of surviving Honolulu Heart Program cohort) aged 71 to 93 years at the time of cognitive testing. Impairment was defined as scoring below the 16th percentile on a validated cognitive assessment scale. Prior MI, stroke, and CABG were established using hospital surveillance, history, and record review. After adjustment for age, years of education, and years of childhood spent in Japan, men with prior stroke were significantly more likely than others to have poor cognitive performance (odds ratio 4.4, 95% confidence limits 3.0 to 6.7). History of > 1 stroke was associated with an odds ratio of 50 (95% confidence limits 10.5 to 238.3). There was no significant association between cognitive performance and > or = 1 prior MI or history of CABG. Time between events and cognitive function testing did not affect results. Analyses support a significant association between clinical stroke and persistent cognitive impairment, but fail to implicate CABG or MI.

Optical parametric oscillation in periodically poled lithium niobate driven by a diode-pumped Q-switched erbium fiber laser

We describe what is to our knowledge the first nanosecond periodically poled lithium niobate (PPLN) optical parametric oscillator (OPO) driven by a fiber laser. The source was frequency doubled by a PPLN sample before pumping a second, 20-mm-long, PPLN crystal. The OPO threshold was <10muJ, with pump depletions of as much as 45% and a tunable signal range of 945-1450 nm (1690-4450-nm idler range). We demonstrated 130-nm signal tuning by varying the pump wavelength and doubling crystal's temperature. Also, we achieved 15-nm tuning with all crystals at a constant temperature. The results demonstrate the potential of the fiber laser:PPLN combination for practical, versatile, and tunable sources.

Generation of high-power blue light in periodically poled LiNbO(3)

We report the generation of 450-mW average blue (473-nm) power by frequency doubling of a diode-pumped 946-nm Nd:YAG laser. We achieved pulsed operation at a high repetition rate (~160kHz) by driving the relaxation oscillations of the laser. A 40% conversion efficiency to the second harmonic was obtained in a single-pass, extracavity, first-order, quasi-phase-matched process in which periodically poled lithium niobate (period 4.5microm , thickness 0.5mm , and length 15mm) at 140 degrees C was used. The resulting high-power blue beam was circular in profile and nearly diffraction limited, indicating that photorefractive effects do not appear to limit device performance.

Highly efficient second-harmonic and sum-frequency generation of nanosecond pulses in a cascaded erbium-doped fiber:periodically poled lithium niobate source

By combining erbium-doped fiber sources based on a large mode-area design and periodically poled lithium niobate, we have obtained single-pass conversion efficiencies of as much as 83% (energy efficiency) for second-harmonic generation into the near IR (768 nm) and of 34% for sum-frequency generation into the green (512 nm) for nanosecond pulses, using first-order quasi-phase matching. Pulse energies in excess of 80microJ of second harmonic have been obtained from systems pumped by a single laser diode.

Effects of walking on mortality among nonsmoking retired men

BACKGROUND

The potential benefit of low-intensity activity in terms of longevity among older men has not been clearly documented. We examined the association between walking and mortality in a cohort of retired men who were nonsmokers and physically capable of participating in low-intensity activities on a daily basis.

METHODS

We studied 707 nonsmoking retired men, 61 to 81 years of age, who were enrolled in the Honolulu Heart Program. The distance walked (miles per day) was recorded at a base-line examination, which took place between 1980 and 1982. Data on overall mortality (from any cause) were collected over a 12-year period of follow-up.

RESULTS

During the follow-up period, there were 208 deaths. After adjustment for age, the mortality rate among the men who walked less than 1 mile (1.6 km) per day was nearly twice that among those who walked more than 2 miles (3.2 km) per day (40.5 percent vs. 23.8 percent, P=0.001). The cumulative incidence of death after 12 years for the most active walkers was reached in less than 7 years among the men who were least active. The distance walked remained inversely related to mortality after adjustment for overall measures of activity and other risk factors (P=0.01).

CONCLUSIONS

Our findings in older physically capable men indicate that regular walking is associated with a lower overall mortality rate. Encouraging elderly people to walk may benefit their health.

Anisotropic focusing characteristics of microdomain structures within crystalline Sr(0.61)Ba(0.39)Nb2O6: the crystal ball

We report the anisotropic focusing characteristics of a spherically configured region of microdomains that have been induced within a cubic-shaped crystal of Ce-doped Sr(0.61)Ba(0.39)Nb2O6. The internal spherical structure focuses extraordinary polarized light, but not ordinary polarized light. The spherical region, which is easily observed via scattering, is formed as the crystal cools after a repoling cycle through the Curie temperature, with an applied field. Analytic modeling of the thermal gradients that exist within the crystal during cooling reveals a small (<1 degrees C) temperature difference between the central and the outside regions. The similarity in shape between these temperature profiles and the observed scattering region suggests a possible mechanism for the growth of this spherical microdomained structure.

Frequency and characteristics of silent dementia among elderly Japanese-American men. The Honolulu-Asia Aging Study

OBJECTIVE

To determine the frequency of unrecognized dementia in a group of men found to have dementia by population survey, and to identify factors associated with the failure of a family informant to recognize significant memory impairment.

DESIGN AND SETTING

The Honolulu-Asia Aging Study, a population-based study of dementia among elderly Japanese-American men living on the island of Oahu, Hawaii. Data for this study were from the dementia prevalence survey, 1991-1993.

STUDY PARTICIPANTS

A total of 191 noninstitutionalized men with dementia who had a reliable family informant.

MAIN OUTCOME MEASURES

Failure of family informants to recognize a problem with thinking or memory in subjects with dementia.

RESULTS

A total of 21% of family informants failed to recognize a problem with memory among subjects subsequently found to have dementia. Among subjects with very mild dementia, 52% of family informants failed to recognize a significant memory problem compared with 13% among more severely demented subjects. Of the subjects with dementia whose family informants did recognize a memory problem, 53% failed to receive a medical evaluation for this problem. For all family informants, increasing age, fewer years of education, less severe dementia, fewer behavioral complications, fewer functional disabilities, and better performance on certain tests of memory and language were significantly associated with the family informant's failure to recognize a problem with memory. When the family informants were wives living with husbands, less severe dementia, fewer behavioral complications, fewer functional disabilities, and intact remote memory were associated with unrecognized dementia.

CONCLUSIONS

Unrecognized dementia was common in our population, especially among mild cases. Cognitive screening programs for the elderly and public education policies designed to increase awareness of early signs of dementia are needed if interventions for individuals with potentially treatable dementias are to be implemented.

Prevalence of dementia in older Japanese-American men in Hawaii: The Honolulu-Asia Aging Study

OBJECTIVE

To determine prevalence of dementia and its subtypes in Japanese-American men and compare these findings with rates reported for populations in Japan and elsewhere.

DESIGN AND SETTING

The Honolulu Heart Program is a prospective population-based study of cardiovascular disease established in 1965. Prevalence estimates were computed from cases identified at the 1991 to 1993 examination. Cognitive performance was assessed using standardized methods, instruments, and diagnostic criteria.

PARTICIPANTS

Subjects were 3734 Japanese-American men (80% of surviving cohort) aged 71 through 93 years, living in the community or in institutions.

MAIN OUTCOME MEASURES

Age-specific, age-standardized, and cohort prevalence estimates were computed for dementia (all cause) defined by 2 sets of diagnostic criteria and 4 levels of severity. Prevalence levels for Alzheimer disease and vascular dementia were also estimated.

RESULTS

Dementia prevalence by Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised ranged from 2.1% in men aged 71 through 74 years to 33.4% in men aged 85 through 93 years. Age-standardized prevalence was 7.6%. Prevalence estimates for the cohort were 9.3% for dementia (all cause), 5.4% for Alzheimer disease (primary or contributing), and 4.2% for vascular dementia (primary or contributing). More than 1 possible cause was found in 26% of cases. The Alzheimer disease/vascular dementia ratio was 1.5 for cases attributed primarily to Alzheimer disease or vascular dementia.

CONCLUSIONS

Prevalence of Alzheimer disease in older Japanese-American men in Hawaii appears to be higher than in Japan but similar to European-ancestry populations. Prevalence of vascular dementia appears to be slightly lower than in Japan, but higher than in European-ancestry populations. Further cross-national research with emphasis on standardized diagnostic methods is needed.

Observations on serum uric acid levels and the risk of idiopathic Parkinson's disease

Uric acid, an antioxidant found in high concentrations in serum and in the brain, has been hypothesized to protect against oxidative damage and cell death in Parkinson's disease. The authors tested this hypothesis among men participating in a 30-year prospective study known as the Honolulu Heart Program. Serum uric acid was measured in 7,968 men at the baseline examination held from 1965 to 1968. Of these men, 92 subsequently developed idiopathic Parkinson's disease (IPD). In analyses adjusted for age and smoking, men with uric acid concentrations above the median at enrollment had a 40% reduction in IPD incidence (rate ratio (RR) = 0.6; 95% confidence interval (CI) 0.4-1.0). Reduced IPD incidence rates persisted in analyses restricted to nonsmokers (RR = 0.5; 95% CI 0.3-1.0) and cases younger than age 75 years (RR = 0.5; 95% CI 0.3-0.9). Incidence rates were not notably affected when analyses were restricted to cases that occurred more than 5 years after uric acid measurement (RR = 0.6; 95% CI 0.4-1.0). Inclusion of known or computed correlates of uric acid in regression models did not substantially change risk of IPD. This study provides prospective evidence of an association between uric acid and reduced occurrence of IPD and indicates that further investigations of this association are warranted.

Evidence against the operation of selective mortality in explaining the association between cigarette smoking and reduced occurrence of idiopathic Parkinson disease

To investigate the association between idiopathic Parkinson disease (IPD) and reduced frequency of prior cigarette smoking, the authors compared the 29-year follow-up mortality rates and IPD incidence rates of men who were either cigarette smokers or nonsmokers at the time of enrollment in the Honolulu Heart Study (1965-1968). Based on IPD cases detected up to June 30, 1994, the age-adjusted incidence rate in smokers was less than half that in nonsmokers: 34.4 versus 94.2 cases per 100,000 person-years of pre-illness follow-up, respectively. When data were stratified by 5-year age group, lower IPD incidence in smokers was observed at all ages between 50 and 90 years. Age-specific mortality trends for smokers and nonsmokers with and without IPD suggested that increased mortality in IPD patients was mostly associated with IPD itself and not with smoking. The slight excess mortality in smokers without IPD, versus nonsmokers without IPD, appeared insufficient to account for the "missing" incident IPD cases in smokers. These IPD incidence and mortality data are not highly consistent with the "selective mortality" hypothesis, which attributes reduced prior smoking frequency, typically reported by persons with IPD, to accelerated mortality in undiagnosed IPD-affected persons who smoke. The "protective" association of cigarette smoking with IPD occurrence may thus be real, suggesting the need for further study of biologic mechanisms of protection.

Case-control study of idiopathic Parkinson's disease and dietary vitamin E intake

A nested case-control study of 84 incident cases of patients with idiopathic Parkinson's disease (PD) detected by June 30, 1994 and 336 age-matched control subjects, compared previously-documented intake of total dietary vitamin E and of selected vitamin E-containing foods. All study subjects had been followed for 27 to 30 years after diet recording in the 8,006-man Honolulu Heart Study cohort. We determined PD outcomes by periodic cohort re-examination and neurologic testing, private physician reports, examination of O'ahu neurologists' office records, and continual death certificate and hospital discharge diagnosis surveillance. Data on vitamin E intake, obtained from three dietary data sets at the time of cohort enrollment (1965 to 1968), included a food-frequency questionnaire and a 24-hour photograph-assisted dietary recall administered by trained dietitians. Although absence of PD was significantly associated with prior consumption of legumes (adjusted OR = 0.27, 95% CI 0.09 to 0.78), a dietary variable preselected for high vitamin E content, neither food categories nor quartiles nor continuous variables of vitamin E consumption were significantly associated with PD occurrence. Though consistent with prior reports of PD protection afforded by legumes, and with speculation on the possible benefits of dietary or supplemental vitamin E in preventing PD, these preliminary data do not conclusively document a beneficial effect of dietary vitamin E on PD occurrence.

Age-related changes in stroke risk in men with hypertension and normal blood pressure

BACKGROUND AND PURPOSE

Stroke is a major contributor to total morbidity and mortality in older individuals, and hypertension is an important risk factor for stroke. Relatively few data exist on whether this relationship changes with age.

METHODS

To examine age-related changes in the relationships between risk of stroke and hypertension, we examined the 6-year incidence of stroke among men aged 45 to 81 years using updated blood pressure data from three examinations of Japanese-American men from the Honolulu Heart Program.

RESULTS

Both the prevalence of hypertension (systolic blood pressure > or = 160 mm Hg or diastolic blood pressure > or = 95 mm Hg or the use of antihypertensive medication) and the 6-year incidence of stroke increased significantly with increasing age (P < .01). The increase in thromboembolic stroke incidence with age was more marked in those who were normotensive at baseline (2.7/1000 in those aged 45 to 54 years to 23.9/1000 in those > or = 65 years; P < .001) than in hypertensive men (20.6/1000 in those aged 45 to 54 years to 33.5/1000 in those > or = 65 years; P < .01). The age-related increase in risk of thromboembolic stroke among normotensive men resulted in a decrease in the percentage of strokes attributable to hypertension (50% in those aged 45 to 54 years to 18% in those > or = 65 years; P < .05). Similar trends were seen for hemorrhagic stroke. There were no age-related changes in the relationships of other major atherosclerotic risk factors with stroke. The hypertension/stroke relationships were present after multivariate adjustment for age, smoking, cholesterol, and other factors.

CONCLUSIONS

In view of the greater prevalence of hypertension and the proven efficacy of treatment in the elderly, these findings do not negate the value of aggressive screening and treatment of hypertension in this age group. However, it appears that other unidentified factors have an increasing role in the causation of stroke with advancing age.

Epidemiologic observations on Parkinson's disease: incidence and mortality in a prospective study of middle-aged men

We determined age-specific and age-adjusted incidence rates and mortality rates of idiopathic Parkinson's disease (PD) in a cohort of men followed for 29 years. Since enrollment in 1965, the Honolulu Heart Study has followed 8,006 American men of Japanese or Okinawan ancestry. Rescreening of the entire cohort, completed in 1994, included attempts to detect all prevalent and incident cases of PD, parkinsonism, and related conditions. PD incidence rates and age-incidence patterns were similar to rates previously published for Caucasian men in Europe and the United States, and were higher than incidence rates published for Asian men living in Asian nations. Prevalence patterns appeared to correspond more closely to patterns observed in developed nations than in Asian nations. PD was associated with markedly increased mortality that appeared to result from effects of both absolute age and disease duration. There was no firm evidence for differences in birth cohort risks of PD. These data may have implications for maturational and environmental theories of PD etiology.

Cigarette smoking and protection from Parkinson's disease: false association or etiologic clue?

We reviewed 46 published reports associating cigarette smoking and Parkinson's disease. Although the majority indicated an approximate halving of smoking frequency in persons with Parkinson's disease, many observers have suggested that the effect could be a spurious result. That the association may be real is suggested by at least six observations: (1) the consistency of findings between independent studies of different design, conducted by different investigators, in different nations, over 35 years; (2) the association's predominance and strength in prospective studies; (3) the apparent detection of a dose-response relation; (4) the inability to explain the association by confounding variables; (5) the flaws in certain arguments against the association's validity; and (6) the identification of a similar association, of similar magnitude, between smoking and reduced occurrence of Alzheimer's disease. A protective association of cigarette smoking for Parkinson's disease may constitute an important etiologic clue.

Body mass index and thromboembolic stroke in nonsmoking men in older middle age. The Honolulu Heart Program

BACKGROUND AND PURPOSE

While evidence suggests that obesity has an independent relation to coronary artery disease, similar findings for stroke have not been established. The purpose of this study was to examine the relation between body mass index and the risk of thromboembolic stroke independently of other risk factors.

METHODS

Since 1965, the Honolulu Heart Program has followed a cohort of men in a prospective study of cardiovascular disease. This article examines the relationship between the baseline measurement of body mass index and the risk of thromboembolic stroke in 1163 nonsmoking men in older middle age (55 to 68 years). Men who had an elevated risk of stroke due to hypertension, diabetes, and other risk factors were excluded from the analysis.

RESULTS

After 22 years of follow-up, the rate of stroke increased significantly with increasing levels of body mass (P < .01). In the bottom tertile of the body mass index, the rate of thromboembolic stroke was 28.7 per 1000 (11/383). In the middle tertile, the rate was increased by 40% to 40.7 per 1000 (16/393), and in the top tertile, the rate of thromboembolic stroke was 55.4 per 1000 (21/387), a twofold excess compared with the bottom tertile. After adjustment for age and the residual effects of confounding risk factors, including systolic blood pressure and serum glucose, the estimated relative risk of stroke for the average body mass index in the top tertile (26.6 kg/m2) compared with that in the bottom tertile (20.3 kg/m2) was 2.1 (95% confidence interval, 1.1 to 4.1). These findings were not affected by coronary events that occurred in the course of follow-up, nor did they appear to be influenced by deaths from other causes.

CONCLUSIONS

We conclude that elevated body mass is associated with an increased risk of thromboembolic stroke in nonsmoking men in older middle age who are free of commonly observed conditions related to cardiovascular disease.

Posterior cortical atrophy. Neuropathologic correlations

OBJECTIVE

A subgroup of patients with progressive dementia has been reported with a marked predominance of symptoms attributed to the dysfunction of the posterior parieto-occipital cortex. These cases have been referred to as posterior cortical atrophy. The objective of this study was to determine whether posterior cortical atrophy is associated with distinct, uniform neuropathologic findings.

DESIGN

Three individuals with progressive dementia that began with higher visual dysfunction (posterior cortical atrophy) were followed up to definitive neuropathologic diagnosis.

RESULTS

Three separate neuropathologic entities were discovered: subcortical gliosis, Alzheimer's disease, and Creutzfeldt-Jakob disease.

CONCLUSION

Posterior cortical atrophy is a clinically homogeneous but pathologically heterogeneous syndrome.

Phase-conjugate fluorozirconate fiber laser operating at 800 nm

We report phase-conjugate feedback into a fluorozirconate optical fiber amplifier at infrared wavelengths. By using a semiconductor laser diode at 807 nm, a grating is established in photorefractive BaTiO(3) that, in the ring configuration, provides feedback into the amplifier necessary for laser action. Once written, the grating is self-sustaining, and lasing is observed even after the laser diode is removed.

Highly efficient self-pumped phase conjugation at near-infrared wavelengths by using nominally undoped BaTiO(3)

Using a nominally undoped crystal of photorefractive BaTiO(3), we have examined self-pumped phase conjugation at near-infrared wavelengths. We report reflectivities as high as 74% between 720 and 800 nm. As expected, the crystal response time increases significantly at longer wavelengths. We believe that this value of reflectivity in the self-pumped geometry is the highest reported nominally undoped crystal.

Olfactory neuroblastoma. Additional immunohistochemical characterization

A panel of 12 antibodies was used to further characterize the immunohistochemical staining profile of olfactory neuroblastoma. The following results were obtained for the 11 neoplasms that were immunostained: neuron-specific enolase 11/11(+), S-100 protein 8/11(+), microtubule-associated protein-2 8/11(+), class III beta-tubulin isotype 9/11(+), neurofilament 200 kD 8/11(+), synaptophysin 7/11(+), glial fibrillary acidic protein 1/11(+), chromogranin A 1/11(+), vimentin 1/11(+), keratin (CAM 5.2) 4/11(+), keratin (AEI/AE3) 0/11(+), and epithelial membrane antigen 0/11(+). Expression of two intermediate filaments was found in 4 of the 11 tumors. The authors' data showing that 72% of olfactory neuroblastomas were S-100 protein positive and only one was immunoreactive for glial fibrillary acidic protein agree with other published immunohistochemical studies. With only a single exception, each of the 11 neoplasms was labeled with one or more antibodies that detect neuronal cytoskeletal proteins (class III beta-tubulin isotype, microtubule-associated protein-2, neurofilament 200 kD). These immunohistochemical results are complementary to the reported electron microscopic findings of intermediate filaments and microtubules in olfactory neuroblastomas.