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J Growdon

Publications and source records attributed to J Growdon.

At least 19 recordsLinked to original sources
PubMed2006

Clinical and biochemical correlates of insoluble alpha-synuclein in dementia with Lewy bodies.

Alpha-synuclein is a major constituent of Lewy bodies, the fibrillar aggregates that form within neurons in Parkinson's disease and dementia with Lewy bodies (DLB). Recent biochemical data show that alpha-synuclein accumulates in Parkinson's disease in a detergent insoluble form. We now examine the relationship between detergent insoluble alpha-synuclein and the presence of Lewy bodies, clinical measures of dementia and biochemical parameters in a series of individuals with DLB. We found that Triton X-100 insoluble alpha-synuclein enriched nearly twofold in the temporal cortex of patients with DLB compared to age-matched controls. By contrast the total amount of alpha-synuclein protein was unchanged. Surprisingly, the degree of Triton X-100 insoluble alpha-synuclein did not correlate with either the duration of illness or the number of Lewy bodies counted using stereological methods from an adjacent block of tissue. However, the Triton X-100 soluble fraction of alpha-synuclein did correlate strongly with the expression of several heat shock proteins (HSPs) in DLB but not control cases, suggesting a coordinated HSP response in DLB neocortex.

Aged↗
PubMed2005

Absence of previously reported variants in the SCNA (G88C and G209A), NR4A2 (T291D and T245G) and the DJ-1 (T497C) genes in familial Parkinson's disease from the GenePD study.

Parkinson's disease (PD) is a neurodegenerative disorder in which relatives of the probands are affected approximately 4 times as frequently as relatives of control subjects. Several genes have been implicated as genetic risk factors for PD. We investigated the presence of six reported genetic variations in the SCNA, NR4A2, and DJ-1 genes in 292 cases of familial Parkinson's disease from the GenePD study. None of the variants were found in the GenePD families. Our results suggest that other variants or genes account for the familial risk of PD within the GenePD study.

Aged↗
PubMed2003

A haplotype at the PARK3 locus influences onset age for Parkinson's disease: the GenePD study.

OBJECTIVE: To identify a haplotype influencing onset age for Parkinson's disease (PD) in the PARK3 region on chromosome 2p13. METHODS: Single nucleotide polymorphisms (SNP) spanning 2.2 Mb and located in or near potential candidate genes were used to fine map the PARK3 region in 527 patients with familial PD, from 264 families. RESULTS: TT homozygotes for rs1876487 (G/T) had a 7.4-year younger mean age at onset (p = 0.005) compared to patients with GT and GG genotypes. Furthermore, SNP flanking the sepiapterin reductase (7,8-dihydrobiopterin: NADP+ oxidoreductase) (SPR) gene, rs1876487 (p = 0.02) and rs1150500 (p = 0.04), were associated with younger onset age among persons who did not carry the 174 allele of D2S1394. The SPR gene is implicated in dopamine synthesis. Haplotype analysis of three SNP-rs2421095, rs1876487, rs1561244-revealed an association with onset age (p = 0.023) and a haplotype of A-T-G alleles was associated with younger onset for PD (p = 0.005). CONCLUSIONS: A haplotype at the PARK3 locus, harboring the SPR gene, is associated with onset age of PD. This may suggest a role for the SPR gene in modifying the age at onset of PD.

Adolescent↗
PubMed2002

Epidemiologic study of 203 sibling pairs with Parkinson's disease: the GenePD study.

OBJECTIVE: To examine patterns of familial aggregation and factors influencing onset age in a sample of siblings with PD. METHODS: Sibling pairs (n = 203) with PD were collected as part of the GenePD study. Standardized family history, medical history, and risk factor data were collected and analyzed. RESULTS: The mean age at onset was 61.4 years and did not differ according to sex, exposure to coffee, alcohol, or pesticides. Head trauma was associated with younger onset (p = 0.03) and multivitamin use with later onset (p = 0.007). Age at onset correlation between sibling pairs was significant (r = 0.56, p = 0.001) and was larger than the correlation in year of onset (r = 0.29). The mean difference in onset age between siblings was 8.7 years (range, 0 to 30 years). Female sex was associated with increased frequency of relatives with PD. The frequency of affected parents (7.0%) and siblings (5.1%) was increased when compared with frequency in spouses (2.0%). CONCLUSIONS: The greater similarity for age at onset than for year of onset in sibling pairs with PD, together with increased risk for biological relatives over spouses of cases, supports a genetic component for PD. Risk to siblings in this series is increased over that seen in random series of PD cases; however, patients in this sample have similar ages at onset and sex distribution as seen for PD generally. These analyses suggest that factors influencing penetrance are critical to the understanding of this disease.

Age of Onset↗
PubMed1998

Unraveling the mystery of cognitive changes in old age: correlation of neuropsychological evaluation with neuropathological findings in the extreme old.

In order to understand what cognitive changes can be expected with aging versus those caused by disease, the New England Centenarian Study examined correlations between neuropsychological evaluation and neuropathological studies of centenarian subjects. Sixty-nine subjects were administered an extensive neuropsychological test battery designed for centenarians. Six brain donors from this group have subsequently died, and neuropathological studies of their brains have been performed to determine the presence of Alzheimer's disease (AD) and other pathological states. Of these six centenarians, three subjects had Clinical Dementia Rating scores of 0 and no dementia on neuropsychological testing, and subsequent neuropathology showed very limited AD changes. In fact, despite a range of neuropsychological findings, none of the subjects in this series met neuropathological criteria for a diagnosis of definite AD. Findings suggest that dementia is not inevitable with aging and that dementia in this age group is surprisingly often not attributable to AD.

Aged↗
PubMed1997

A controlled trial of selegiline, alpha-tocopherol, or both as treatment for Alzheimer's disease. The Alzheimer's Disease Cooperative Study.

BACKGROUND: There is evidence that medications or vitamins that increase the levels of brain catecholamines and protect against oxidative damage may reduce the neuronal damage and slow the progression of Alzheimer's disease. METHODS: We conducted a double-blind, placebo-controlled, randomized, multicenter trial in patients with Alzheimer's disease of moderate severity. A total of 341 patients received the selective monoamine oxidase inhibitor selegiline (10 mg a day), alpha-tocopherol (vitamin E, 2000 IU a day), both selegiline and alpha-tocopherol, or placebo for two years. The primary outcome was the time to the occurrence of any of the following: death, institutionalization, loss of the ability to perform basic activities of daily living, or severe dementia (defined as a Clinical Dementia Rating of 3). RESULTS: Despite random assignment, the baseline score on the Mini-Mental State Examination was higher in the placebo group than in the other three groups, and this variable was highly predictive of the primary outcome (P<0.001). In the unadjusted analyses, there was no statistically significant difference in the outcomes among the four groups. In analyses that included the base-line score on the Mini-Mental State Examination as a covariate, there were significant delays in the time to the primary outcome for the patients treated with selegiline (median time, 655 days; P=0.012), alpha-tocopherol (670 days, P=0.001) or combination therapy (585 days, P=0.049), as compared with the placebo group (440 days). CONCLUSIONS: In patients with moderately severe impairment from Alzheimer's disease, treatment with selegiline or alpha-tocopherol slows the progression of disease.

Activities of Daily Living↗
PubMed1996

Rationale and design of a multicenter study of selegiline and alpha-tocopherol in the treatment of Alzheimer disease using novel clinical outcomes. Alzheimer's Disease Cooperative Study.

This report describes the rationale and design of a clinical trial using selegiline (10 mg/day) and alpha-tocopherol (2,000 IU/day) to slow the progression of dementia in Alzheimer disease (AD). This study was developed by the Alzheimer's Disease Cooperative Study (ADCS), a consortium of clinical research centers actively involved in AD research. The major goal of the consortium is to design and conduct clinical investigations leading to the development of treatments for AD. This study uses a randomized double-blind, placebo-controlled, 2 x 2 factorial, parallel group design to test two drugs for the treatment of AD. The primary outcome of the study is the time to reach any one of the following four endpoints: death, institutionalization, loss of two of three basic activities of daily living, and progression of Clinical Dementia Rating (CDR) stage from 2 to 3. Patients with moderately severe disease (CDR = 2) were enrolled and evaluated 10 times over a period of 2 years to determine if these agents reduce the time to reach any endpoint. A database from the Consortium to Establish a Registry for Alzheimer's Disease indicated adequate power analyses to observe a treatment effect on this clinically meaningful outcome measure. Recruitment and baseline characteristics of the population are provided. The rationale for the choice of a factorial design, the use of a novel, clinically meaningful endpoint, and the selection of a cohort of patients with AD of moderate severity are discussed.

Aged↗
PubMed1995

Environment-driven responses in progressive supranuclear palsy.

The neurological signs and behaviors that accompany degenerative diseases associated with fronto-striatal dysfunction are incompletely described. We observed several novel environmentally-driven behaviors in seven patients with progressive supranuclear palsy (PSP). All patients had cognitive deficits with greatest impairments on tests of frontal lobe function, and frontal lobe cerebral perfusion was significantly reduced in 4 of the 5 who had single photon emission computed tomography (SPECT) brain scans. Visual grasping, in which a patient's gaze was attracted to an incidental object in the environment such as a TV set or mirror, was preeminent. Once fixed, there was inability to release the gaze and shift to another object. In other instances, removing a table placed in front of a patient or unbuckling of his seat belt would make him stand up, which was impossible on command. Similarly, playing music would induce rhythmic foot beating, which was never obtained on command. There were compulsive utilization behaviors, such as repetitively picking up and replacing the telephone for no apparent reason. As expected, there were signs of heightened facial reflexes, grasp reflexes, apraxia of eyelid opening, echolalia and echopraxia. We postulate that these stimuli-oriented behaviors stem from parietal lobe disinhibition due to fronto-striatal dysfunction.

Aged↗
PubMed1994

The effect of deprenyl and tocopherol on cognitive performance in early untreated Parkinson's disease. Parkinson Study Group.

We conducted prospective cognitive assessments over 14 +/- 6 (mean +/- SD) months of observation as part of the multicenter trial Deprenyl and Tocopherol Antioxidative Therapy of Parkinsonism (DATATOP), which involved 800 patients with early untreated Parkinson's disease. We administered tests that measured memory, visuospatial, and frontal lobe functions. Subjects were randomly assigned to receive placebo, deprenyl (10 mg/d), tocopherol (2,000 IU/d), or both deprenyl and tocopherol. We analyzed treatment effects using annualized rates of cognitive change. We performed exploratory analyses to identify potential clinical and demographic correlates of cognitive performance. There was no significant effect of either deprenyl or tocopherol on cognitive test performance. In early untreated Parkinson's disease, cognitive performance appears to be stable and unrelated to either motor deterioration or treatment with deprenyl or tocopherol.

Aged↗
PubMed1992

An antispasticity effect of threonine in multiple sclerosis.

To determine whether the naturally occurring amino acid threonine, a potential precursor for glycine biosynthesis in the spinal cord, has an effect on spasticity in multiple sclerosis, 26 ambulatory patients were entered into a randomized crossover trial. Threonine administered at a total daily dose of 7.5 g reduced signs of spasticity on clinical examination, although no symptomatic improvement could be detected by the examining physician or the patient. In contrast to the side effects of sedation and increased motor weakness associated with antispasticity drugs commonly used for the treatment of multiple sclerosis, no side effects or toxic effects of threonine were identified. Levels of threonine were elevated in serum and cerebrospinal fluid during treatment, but glycine levels did not change. Enhancement by threonine of glycinergic postsynaptic inhibition of the motor reflex arc in the spinal cord may represent a non-sedating, nontoxic approach to the management of spasticity in multiple sclerosis.

Adult↗
PubMed1991

Idazoxan treatment in progressive supranuclear palsy.

To confirm the preliminary report that increases in norepinephrine neurotransmission improve motor performance, we administered the investigational drug idazoxan (IDA) to nine patients with progressive supranuclear palsy (PSP) according to a double-blind crossover protocol. There were seven women and two men, whose mean age was 70 years and mean duration of illness 4 years. All had an advanced parkinsonian syndrome, supranuclear ocular motor palsies, and poor responses to dopaminergic drugs. During administration of 40 mg tid of IDA, the total score and the motor subscale score of the United Parkinson's Disease Rating Scale significantly decreased. Features that improved most included mobility, balance, gait, and measures of digital dexterity. There were no significant changes in any measure during placebo administration. Corticobulbar manifestations and eye movements were not significantly improved during treatment. Side effects of IDA included transient hypertension, tachycardia, action tremor, flushing, and sweating, but none was so severe that any patient withdrew from the study. Among the few attempted treatments of PSP, IDA is the first medication shown in a double-blind study to improve aspects of motor function.

Adrenergic alpha-Antagonists↗
PubMed1987

Absence of duplication of chromosome 21 genes in familial and sporadic Alzheimer's disease.

The possibility that Alzheimer's disease (AD) is caused by overexpression or duplication of one or more genes on chromosome 21 has been raised by the observation of AD-like neuropathologic changes in individuals with Down syndrome and by the mapping of both the defect for familial AD and the amyloid beta protein gene to this autosome. Possible duplication on chromosome 21 was investigated in both familial and sporadic AD by means of restriction fragment length polymorphisms for the amyloid and SODI loci, as well as for DNA markers in the vicinity of the familial AD defect and in the critical Down syndrome region of chromosome 21. No evidence of increased DNA dosage was observed in either brain or leukocytes of patients with inherited or sporadic forms of AD. Duplication of these regions is therefore not a frequent event in either form of AD. Furthermore, no significant allelic association was detected between AD and any of the loci, including the amyloid and SODI genes, providing no support for the hypothesis that defects in these specific genes are the primary cause of AD.

Alleles↗
PubMed1987

Search for the familial Alzheimer's disease gene.

The application of molecular genetic techniques to the study of autosomal dominantly inherited Familial Alzheimer's Disease may provide a means to determine the chromosomal location of the defective gene causing this form of Alzheimer's disease. Knowledge of the chromosomal location of the defective gene will provide a basis for isolating and characterizing this gene. Preliminary investigations indicate that several candidate genes can be excluded as the site of the defect. Current data also indicate that the defective gene does not reside close to random DNA markers on the distal portion of chromosome 21. Additional DNA markers on the proximal portion of chromosome 21 long arm are currently being investigated.

Alzheimer Disease↗
PubMed1985

d-Fenfluramine selectively suppresses carbohydrate snacking by obese subjects.

Twenty obese inpatients who claimed to crave carbohydrate-rich foods were given d-fenfluramine (15 mg p.o., twice daily) or its placebo, double-blind, for two consecutive eight-day periods. Food choices were measured on treatment days 1, 7, and 8 by giving the subjects access to unlimited portions of six isocaloric meal foods (three high in carbohydrate and three high in protein) and of 10 isocaloric snack foods (five high in protein and five high in carbohydrate) available 24 hours a day in a computerized vending machine. d-fenfluramine reduced mealtime calorie intake by only 16% (from 1940 +/- 94 to 1630 +/- 92; p < .001), mealtime carbohydrate by 22%, and had no significant effect on mealtime protein consumption; in contrast, snack calorie intake was reduced by 41% (from 707 +/- 97 to 414 +/- 46; p < .001), and snack carbohydrate intake by the same proportion. The mean number of carbohydrate-rich snacks consumed per day decreased from 5.8 +/- 0.8 to 3.4 +/- 0.4 (p < .01), while that of protein-rich snacks failed to change signficantly (i.e., from 0.7 +/- 0.2 to 0.5 +/- 0.2).

Adult↗
PubMed1982

Oral dyskinesia in rats following brain lesions and neuroleptic drug administration.

After 10-12 weeks of chronic haloperidol administration rats with frontal cortex ablations or lesions induced by intracerebroventricular infection of 6-hydroxydopamine developed vacuous chewing behavior at a fairly stable frequency (bifrontal ablations had 15-20, 6-hydroxy-dopamine lesioned rats 7-12 chewing movements/min). This behavior persisted for 10 weeks after the last injection of haloperidol decanoate. However, rats with frontal cortex lesions developed a low rate of vacuous chewings (4-8 chewings/min) even without haloperidol administration. Bilateral intrastriatal injections of kainic acid in combination with chronic haloperidol administration did not cause chewing movements in excess of unlesioned haloperidol-treated controls. Pharmacological tests of this animal model for tardive dyskinesia (TD) revealed similarities to human TD, but also differences. Dopamine agonists (apomorphine) and antagonists (haloperidol) both lowered chewing behavior analogous to reported effects on TD and so did gabaculine. The cholinergic drugs physostigmine and pilocarpine, however, increased chewing in rats, while anticholinergics (atropine) reduced it, in contrast to reported effects on human TD.

Acetylcholine↗