Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Guam”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources

Parkinsonism-dementia complex on Guam - overview of clinical aspects.

Parkinsonism-dementia complex (PDC) is the second most common neurodegenerative disorder in Guam, after amyotrophic lateral sclerosis (ALS). PDC was first described by Hirano 1961. A familial appearance is seen among some PDC cases, which may also include ALS, and vice versa, but subsequent research including pedigree analysis, prospective case control registries, and the search for specific gene markers has failed to yield a satisfactory genetic explanation. Important diagnostic indicators of the illness include rigido-akinetic type Parkinsonism and severe dementia.In PDC, rigidity is so marked that postural deformities such as a generally flexed posture become rather prominent. Gait disturbances are a common initial symptom. Hyperreflexia and spinal muscular atrophy, developing mainly in the distal extremities, are frequently observed. These mixed-syndrome patients can be seen as clear support for the view that Guam ALS and PDC constitute a single mixed disease entity with a spectrum of clinical expression. The present paper offers an overview and description of the clinical features of PDC.

Age of Onset↗

Pyramidal neuron loss is matched by ghost tangle increase in Guam parkinsonism-dementia hippocampus.

The parkinsonism dementia complex of Guam (bodig disease) is characterized by severe neurofibrillary tangle (NFT) development without the senile plaques which characterize Alzheimer's disease. Here we analyze eight cases of bodig and three control cases from Guam, for the numbers of unaffected pyramidal neurons, intracellular NFTs (iNFTs), and extracellular NFTs (eNFTs) in hippocampal sectors CA1 and CA4. We utilized Alz50 immunostaining to identify iNFTs, amyloid P immunostaining to identify eNFTs, and cresyl violet staining to identify the surviving pyramidal neurons. We developed a modification of the Bielschowsky silver staining method which distinguished iNFTs from eNFTs and found the numbers of iNFTs and eNFTs identified by this method to be comparable to those obtained by immunohistochemical staining. In CA4, the combined total of unaffected pyramidal neurons, iNFTs and eNFTs was found to be remarkably constant in all the cases studied. The density of eNFTs correlated significantly and negatively with the density of surviving neurons, which included unaffected neurons and iNFTs. CA1 was more intensely affected than CA4. The combined total of unaffected pyramidal neurons, iNFTs and eNFTs was still relatively constant, although greater variability was recorded. Our results suggest that loss of pyramidal neurons is proportional to the appearance of eNFTs. The eNFTs accumulate, without evidence of disappearance through phagocytosis.

Adult↗

Progressive supranuclear palsy on Guam.

This is the first report demonstrating that progressive supranuclear palsy (PSP) exists on Guam. This 75-year-old Guamanian Chamorro patient with slight dementia and rigidity with restriction of ocular up gaze was diagnosed as parkinsonism-dementia complex (PDC) of Guam clinically. However, neurofibrillary tangles (NFTs) were scarcely seen in the cerebral cortices and hippocampus, but many NFTs, composed of 15-17 nm straight tubules, were detected in the subthalamic nucleus and brain stem. A large number of tuft-shaped astrocytes were observed in the putamen and motor cortex, and numerous argyrophilic grains were seen in the CA1 and subiculum. These pathological findings are different from those of PDC and consistent with PSP. The present case indicates that PSP and PDC clinically resemble each other, and that precise neuropathological examination is indispensable for the final diagnosis of the patient with parkinsonism, dementia and disturbance of vertical external ocular movement.

Aged↗

Pathologic findings in the retinal pigment epitheliopathy associated with the amyotrophic lateral sclerosis/parkinsonism-dementia complex of Guam.

BACKGROUND: A pigment epitheliopathy that resembles ophthalmomyiasis interna occurs in approximately 10% of a large sample of the Chamorro population of Guam age 39 years or older; the rate is approximately 50% among those who have amyotrophic lateral sclerosis or Parkinsonism-dementia complex (lytico bodig). METHODS: Since publication of an earlier clinical report of affected patients, several of them have died of their neurologic disease, and their eyes were obtained for pathologic study. This is the first pathologic report of the retinal pigment epitheliopathy seen in the setting of amyotrophic lateral sclerosis/Parkinsonism-dementia complex of Guam and is based on examination of 13 eyes from 7 patients. RESULTS/CONCLUSION: Focal areas of attenuation of the retinal pigment epithelium in association with a reduced amount of intracellular pigment correlated with the funduscopic and gross appearance. No larvae were seen, and there was no evidence of inflammation. The pathogenesis of this pigment epitheliopathy remains undetermined.

Amyotrophic Lateral Sclerosis↗

Risk assessment of an acetaminophen baiting program for chemical control of brown tree snakes on Guam: evaluation of baits, snake residues, and potential primary and secondary hazards.

The brown tree snake (Boiga irregularis) is a significant ecological, agricultural, and economic pest on Guam. Acetaminophen has recently been identified as a promising snake toxicant. Subsequent experimentation has shown that acetaminophen-mouse baits are readily consumed by and acutely toxic to browntree snakes. Before implementing an island-wide acetaminophen-mouse baiting program for the reducton of brown tree snake populations,the potential risks to nontarget wildlife must be evaluated. Quantification of nontarget hazards by comparing potential exposure levels to toxicity values suggested a significant level of concern for rodents, cats, pigs, and birds. For these species, subsequent calculations and field and laboratory experiments, which quantified acetaminophen consumption under field conditions, indicated that acetaminophen consumption was minimal. These results indicate that the advantages of using acetaminophen to reduce brown tree snake populations on Guam outweigh the minimal risks to nontarget feral and wildlife species.

Acetaminophen↗

A research note on body mass, physical aggression, and the competitiveness of Asian-Pacific Islander adolescents in Guam.

This study uses the evolutionary model to guide an exploration of the effects of body mass on aggressive and competitive behaviors among Asian-Pacific adolescents in Guam. Using a probability sample of Guam's high-school students, the results of logistic regressions suggest that adolescent females with greater body mass are more likely to engage in physical fights (aggression) and to participate in team sports (competitiveness). Ethnic differences indicate the possibility that individuals with lower body mass may be less likely to participate in physically aggressive acts and team sports. Alternate theoretical explanations for the results are also considered.

Adolescent↗

Neighborhood environment and opportunity to try methamphetamine ("ice") and marijuana: evidence from Guam in the Western Pacific region of Micronesia.

Although the American popular press and films might generally lead one to think otherwise, illegal drug use and drug trafficking occur outside the boundaries of disadvantaged American inner-city neighborhoods. Nonetheless, the occurrence of youthful drug involvement may be determined by similar community conditions in many parts of the world. In Spring 1998, a probability sample of 776 high school students living in Guam, Micronesia, completed a self-report anonymous survey, one that assessed their village and metropolitan neighborhood environments as well as drug involvement. On Guam, higher levels of neighborhood disadvantage were associated with youths being more likely to have been offered a chance to try drugs. This study adds new evidence on the potential importance of environmental and psychosocial contexts of neighborhood environment that might help account for the nonrandom distribution of youthful drug involvement.

Adolescent↗

Neurofibrillary degeneration on Guam: frequency in Chamorros and non Chamorros with no known neurological disease.

In a neuropathological study of the brains of 69 members of the Guamanian Chamorro population without known evidence of dementia, parkinsonism or amyotrophic lateral sclerosis, the incidence and severity of neurofibrillary degeneration was determined in relation to age at death. It was found that neurofibrillary degeneration is present at an earlier age than has been reported for a comparable population in Japan, and much earlier than reported for two similarly comparable English populations. Our data suggests that neurofibrillary degeneration is the common denominator of the Guam neurological syndromes of parkinsonian dementia, amyotrophic lateral sclerosis and dementia without parkinsonism. This conclusion would imply that the aetiological factor of neurofibrillary degeneration is more widely dispersed in the population than suggested by the cases of parkinsonian dementia and amyotrophic lateral sclerosis alone. Both sexes were equally affected while clinical parkinsonian dementia is three times more frequent among males. The sample data suggests a positive association with the amyotrophic lateral sclerosis-parkinsonian dementia rate in village of birth and residence, and also with family history; the results in the small subsamples are not significant. Senile plaques were found in few control cases in this study, just as there has been a relative absence of senile plaques in cases of parkinsonian dementia. In a small group of Caucasians who had spent many of their adult years on Guam, the frequency of neurofibrillary degeneration in relationship to age was comparable to that in the English populations.

Adolescent↗

Acute hemorrhagic conjunctivitis: a mixed virus outbreak among Vietnamese refugees on Guam.

In May 1975 the authors investigated an outbreak of acute hemorrhagic conjunctivitis that affected an estimated 29,000 refugees from South Vietnam who stayed on Guam while en route to the United States. Illness usually lasted6-10 days and was characterized by conjunctival injection (100%), lid edema (84%), eye irritation (81%) and subconjunctival hemorrhages (45%). Conjunctival swabs and paired serum specimens on a limited number of patients implicated enterovirus 70 as a major etiologic agent and adenovirus 11 as a less frequent agent. Adenovirus 8 and herpes simplex virus caused concurrent, sporadic cases of keratoconjunctivitis. Forty-three per cent of the refugees in a sample of 604 refugees were affected, and the attack rate was highest on evacuation vessels where crowding and poor sanitation facilitated person-to-person spread of infection. Because the outbreak subsided on Guam, and because infection was transmitted there to only 13 of about 1300 Americans in frequent contact with affected refugees, the risk of secondary outbreaks inthe United States appeared small.

Acute Disease↗

Cholinergic deficits in the brains of patients with parkinsonism-dementia complex of Guam.

Patients with parkinsonism-dementia complex (PDC) of Guam showed moderate loss of choline acetyl transferase activity in the midfrontal and inferior parietal cortex, and severe loss in the superior temporal cortex. This deficit was similar to that seen in Alzheimer's disease and less severe than Lewy body disease. Thus, cholinergic deficits in the neocortex might contribute to some of the cognitive alterations in PDC of Guam.

Acetylcholine↗

Magnesium deficiency over generations in rats with special references to the pathogenesis of the Parkinsonism-dementia complex and amyotrophic lateral sclerosis of Guam.

Parkinsonism-dementia complex (PDC) and amyotrophic lateral sclerosis (ALS) are fatal neurological diseases. The incidence on Guam was very high between 1950 and 1965 but decreased dramatically after 1965. It is thought that drinking water containing low levels of calcium (Ca) and magnesium (Mg), and high levels of aluminum and of a plant excitatory neurotoxin are involved in the pathogenesis of these diseases. The present experiment was performed in rats that were exposed to low Ca and/or Mg intake over two generations, thus simulating the conditions of human life on Guam, where several generations live continuously in the same environment. Significant loss of dopaminergic neurons was identified exclusively in the substantia nigra in 1-year-old rats that had been exposed continuously to low Mg intake (one-fifth of the normal level) over generations. The present study suggests that low Mg intake over generations may be involved in the pathogenesis of substantia nigra degeneration in humans.

Amyotrophic Lateral Sclerosis↗

Occurrence of beta-methylamino-l-alanine (BMAA) in ALS/PDC patients from Guam.

We tested the brain tissues of the Chamorro people of Guam who died of amyotrophic lateral sclerosis/Parkinsonism dimentia complex (ALS/PDC) for the neurotoxin beta-methylamino-l-alanine (BMAA). We used validated high-pressure liquid chromatography and liquid chromatography-mass spectrometry analyses to test well-characterized archival tissues of the superior frontal gyrus from eight Chamorros from Guam and a comparison group of 15 Canadians. BMAA was found as a free amino acid in 83% of Chamorro ALS/PDC patients (3-10 microg/g) as a protein-associated amino acid in 100% of the Chamorro individuals (149-1190 microg/g). Both forms of BMAA were also found at comparable levels in two Canadians who died of progressive neurodegenerative disease. BMAA, which is produced by cyanobacteria, may be associated with some cases of neurodegenerative disease.

Adult↗

Guam amyotrophic lateral sclerosis-parkinsonism-dementia linked to a plant excitant neurotoxin.

The decline in the high incidence of amyotrophic lateral sclerosis, parkinsonism, and Alzheimer-type dementia among the Chamorro population of the western Pacific islands of Guam and Rota, coupled with the absence of demonstrable viral and hereditable factors in this disease, suggests the gradual disappearance of an environmental factor selectively associated with this culture. One candidate is seed of the neurotoxic plant Cycas circinalis L., a traditional source of food and medicine which has been used less with the Americanization of the Chamorro people after World War II. Macaques were fed the Cycas amino acid beta-N-methylamino-L-alanine, a low-potency convulsant that has excitotoxic activity in mouse brain, which is attenuated by N-methyl-D-aspartate receptor antagonists. These animals developed corticomoto-neuronal dysfunction, parkinsonian features, and behavioral anomalies, with chromatolytic and degenerative changes of motor neurons in cerebral cortex and spinal cord. In concert with existing epidemiological and animal data, these findings support the hypothesis that cycad exposure plays an important role in the etiology of the Guam disease.

Amino Acids, Diamino↗

Hearing loss and otitis media on Guam: impact of professional services.

In less than two decades, there has been a dramatic reduction in the prevalence of otitis media and perforations among Guam's school-aged children. In addition, hearing loss due to chronic middle ear disease as a cause of disqualification from military service has dropped from a first rank order cause to next-to-last. However, there has been no reduction in the prevalence of otitis media in the preschool population. The reduction in chronic ear disease is the result of improved access to primary care, intensive hearing screening, wide availability of audiologic diagnostic and follow-up services, and comprehensive otologic care. It is essential that these services continue to be available to Guam's children to avoid a reversal of these dramatic gains. Attention must now focus on how to achieve similar gains for Micronesian children who remain restricted in their access to these resources.

Adolescent↗

Biomagnification of cycad neurotoxins in flying foxes: implications for ALS-PDC in Guam.

Beta-methylamino-L-alanine (BMAA) occurs in higher levels in museum specimens of the Guamanian flying fox than in the cycad seeds the flying foxes feed on, confirming the hypothesis that cycad neurotoxins are biomagnified within the Guam ecosystem. Consumption of a single flying fox may have resulted in an equivalent BMAA dose obtained from eating 174 to 1,014 kg of processed cycad flour. Traditional feasting on flying foxes may be related to the prevalence of neuropathologic disease in Guam.

Amino Acids, Diamino↗

Odor identification deficit of the parkinsonism-dementia complex of Guam: equivalence to that of Alzheimer's and idiopathic Parkinson's disease.

Olfactory dysfunction is among the first signs of Alzheimer's disease (AD), idiopathic Parkinson's disease (PD), and the parkinsonism-dementia complex (PDC) of Guam. We have recently demonstrated that the odor identification and detection deficits of patients with PD are equivalent to those of patients with mild AD when subtle differences in cognitive function are statistically controlled for by analysis of covariance. In contrast, patients with progressive supranuclear palsy (PSP) and patients with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced parkinsonism evidence olfactory function much more similar to that of normal controls. In the present study, we administered the University of Pennsylvania Smell Identification Test and the Picture Identification Test to 24 patients with early signs of the PDC of Guam and statistically compared their test scores to those of 24 early-stage AD and 24 early-stage PD patients of similar age and gender from the United States mainland. Although the PDC group evidenced slightly more difficulty in identifying pictures than did the other 2 groups, the odor identification deficit associated with this disorder was of the same magnitude as that observed in AD and PD, suggesting that olfactory testing cannot be used to distinguish among these 3 diseases and that the olfactory dysfunction of these disorders may reflect a common neurologic substrate.

Adult↗

ApoE and CYP2D6 polymorphism with and without parkinsonism-dementia complex in the people of Chamorro, guam.

Parkinsonism-dementia complex (PDC), a neurodegenerative disorder in the Chamorro, Guam population, has been epidemiologically ascribed to the ingestion of the neurotoxin cycasin. This disease is characterized neuropathologically by the presence of abundant neurofibrillary tangles (NFTs). We analyzed a genetic risk factor of Alzheimer's disease (AD), apolipoprotein E, hypothesized to be linked to NFT formation, and a genetic risk factor of Parkinson's disease (PD), CYP2D6 mutation, linked to slower metabolism of exogenous toxins, in Chamorro, Guam individuals with and without PDC. The representation of the G-to-C mutation in exon 9 of the CYP2D6 gene was higher in Chamorro and Filipino than in Caucasian individuals, but this mutant allele had similar high frequencies in both PDC patients and healthy Chamorro individuals. We found no alleles of these genes associated with AD or PD to be overrepresented among those with PDC.

Adult↗

Neurodegenerative diseases of Guam: analysis of TAU.

Mutations in the tau gene have been described in families affected by frontotemporal dementia with parkinsonism linked to chromosome 17. The authors performed a genetic and biochemical analysis of this gene and its product in the parkinsonism dementia complex of Guam, a disorder characterized by the extensive formation of neurofibrillary tangles. The tau gene is not a primary cause of the parkinsonism dementia complex of Guam.

Aged↗