Aß (Amyloid Beta) and Tau Tangle Pathology Modifies the Association Between Small Vessel Disease and Cortical Microinfarcts.

BACKGROUND AND PURPOSE: There is increasing recognition of the importance of cortical microinfarcts to overall brain health, cognition, and Alzheimer dementia. Cerebral small vessel pathologies are associated with microinfarcts and frequently coexist with Alzheimer disease; however, the extent to which Aß (amyloid beta) and tau pathology modulates microvascular pathogenesis is not fully understood. Study objective was to examine the relationship of small vessel pathologies, arteriolosclerosis, and cerebral amyloid angiopathy, with cortical microinfarcts in people with differing levels of Aß or tau tangle burden. METHODS: Participants were 1489 autopsied older people (mean age at death, 89 years; 67% women) from 1 of 3 ongoing clinical-pathological cohort studies of aging. Neuropathological evaluation identified cortical Aß and tau tangle burden using immunohistochemistry in 8 brain regions, provided semiquantitative grading of cerebral vessel pathologies, and identified the presence of cortical microinfarcts. Logistic regression models adjusted for demographics and atherosclerosis and examined whether Aß or tau tangle burden modified relations between small vessel pathologies and cortical microinfarcts. RESULTS: Cortical microinfarcts were present in 17% of older people, moderate-to-severe cerebral amyloid angiopathy pathology in 36%, and arteriolosclerosis in 34%. In logistic regression models, we found interactions with Aß and tau tangles, reflecting that the association between arteriolosclerosis and cortical microinfarcts was stronger in the context of greater Aß (estimate, 0.15; SE=0.07; P=0.02) and tau tangle burden (estimate, 0.13; SE=0.06; P=0.02). Interactions also emerged for cerebral amyloid angiopathy, suggesting that the association between cerebral amyloid angiopathy and cortical microinfarcts is more robust in the presence of higher Aß (estimate, 0.27; SE=0.07; P<0.001) and tangle burden (estimate, 0.16; SE=0.06; P=0.005). CONCLUSIONS: These findings suggest that in the presence of elevated Aß or tangle pathology, small vessel pathologies are associated with greater microvascular tissue injury, highlighting a potential link between neurodegenerative and vascular mechanisms.

Cognitive impairment, decline and fluctuations in older community-dwelling subjects with Lewy bodies.

Lewy bodies are common in the ageing brain and often co-occur with Alzheimer's disease pathology. There is little known regarding the independent role of Lewy body pathology in cognition impairment, decline and fluctuations in community-dwelling older persons. We examined the contribution of Lewy body pathology to dementia, global cognition, cognitive domains, cognitive decline and fluctuations in 872 autopsied subjects (mean age = 87.9 years) from the Rush Religious Order Study (n = 491) and Memory and Aging Project (n = 381) longitudinal community-based clinical-pathological studies. Dementia was based on a clinical evaluation; annual cognitive performance tests were used to create a measure of global cognition and five cognitive domains. Lewy body type was determined by using α-synuclein immunostained sections of substantia nigra, limbic and neocortical regions. Statistical models included multiple regression models for dementia and cognition and mixed effects models for decline. Cognitive fluctuations were estimated by comparing standard deviations of individual residuals from mean trajectories of decline in those with and without Lewy bodies. All models controlled for age, sex, education, Alzheimer's disease pathology and infarcts. One hundred and fifty-seven subjects (18%) exhibited Lewy body pathology (76 neocortical-type, 54 limbic-type and 27 nigra-predominant). One hundred and three (66%) subjects with Lewy body pathology had a pathologic diagnosis of Alzheimer's disease. Neocortical-type, but not nigral-predominant or limbic-type Lewy body pathology was related to an increased odds of dementia (odds ratio = 3.21; 95% confidence interval = 1.78-5.81) and lower cognition (P < 0.001) including episodic memory function (P < 0.001) proximate to death. Neocortical-type Lewy body pathology was also related to a faster decline in global cognition (P < 0.001), decline in all five specific cognitive domains (all P-values < 0.001), and to fluctuations in decline of working and semantic memory (P-values < 0.001). Limbic-type Lewy body pathology was related to lower and faster decline in visuospatial skills (P = 0.042). The relationship of Lewy body pathology to cognition and dementia was not modified by Alzheimer's disease pathology. Neocortical-type Lewy body pathology is associated with increased odds of dementia; lower and more rapid decline in all cognitive domains including episodic memory and fluctuations in decline in semantic and working memory. Limbic-type Lewy body pathology is specifically associated with lower and more rapid decline in visuospatial skills. The effect of Lewy body pathology on cognition appears to be independent of Alzheimer's disease pathology.

Mediterranean-Dash Intervention for Neurodegenerative Delay (MIND) Diet Slows Cognitive Decline After Stroke.

OBJECTIVE: This study sought to determine if the MIND diet (a hybrid of the Mediterranean and Dash diets, with modifications based on the science of nutrition and the brain), is effective in preventing cognitive decline after stroke. DESIGN: We analyzed 106 participants of a community cohort study who had completed a diet assessment and two or more annual cognitive assessments and who also had a clinical history of stroke. Cognition in five cognitive domains was assessed using structured clinical evaluations that included a battery of 19 cognitive tests. MIND diet scores were computed using a valid food frequency questionnaire (FFQ). Dietary components of the MIND diet included whole grains, leafy greens and other vegetables, berries, beans, nuts, lean meats, fish, poultry, and olive oil and reduced consumption of cheese, butter, fried foods, and sweets. MIND diet scores were modeled in tertiles. The influence of baseline MIND score on change in a global cognitive function measure and in the five cognitive domains was assessed using linear mixed models adjusted for age and other potential confounders. RESULTS: With adjustment for age, sex, education, APOE-ε4, caloric intake, smoking, and participation in cognitive and physical activities, the top vs lowest tertiles of MIND diet scores had a slower rate of global cognitive decline (ß = .08; CI = 0.0074, 0.156) over an average of 5.9 years of follow-up. CONCLUSIONS: High adherence to the MIND diet was associated with a slower rate of cognitive decline after stroke.

Respiratory muscle strength predicts decline in mobility in older persons.

OBJECTIVES: To test the hypothesis that respiratory muscle strength is associated with the rate of change in mobility even after controlling for leg strength and physical activity. METHODS: Prospective study of 890 ambulatory older persons without dementia who underwent annual clinical evaluations to examine change in the rate of mobility over time. RESULTS: In a linear mixed-effect model adjusted for age, sex, and education, mobility declined about 0.12 unit/year, and higher levels of respiratory muscle strength were associated with a slower rate of mobility decline (estimate 0.043, SE 0.012, p < 0.001). Respiratory muscle strength remained associated with the rate of change in mobility even after controlling for lower extremity strength (estimate 0.036, SE 0.012, p = 0.004). In a model that included terms for respiratory muscle strength, lower extremity strength and physical activity together, all three were independent predictors of mobility decline in older persons. These associations remained significant even after controlling for body composition, global cognition, the development of dementia, parkinsonian signs, possible pulmonary disease, smoking, joint pain and chronic diseases. CONCLUSION: Respiratory muscle strength is associated with mobility decline in older persons independent of lower extremity strength and physical activity. Clinical interventions to improve respiratory muscle strength may decrease the burden of mobility impairment in the elderly.

Entorhinal Cortex: Antemortem Cortical Thickness and Postmortem Neurofibrillary Tangles and Amyloid Pathology.

BACKGROUND AND PURPOSE: The entorhinal cortex, a critical gateway between the neocortex and hippocampus, is one of the earliest regions affected by Alzheimer disease-associated neurofibrillary tangle pathology. Although our prior work has automatically delineated an MR imaging-based measure of the entorhinal cortex, whether antemortem entorhinal cortex thickness is associated with postmortem tangle burden within the entorhinal cortex is still unknown. Our objective was to evaluate the relationship between antemortem MRI measures of entorhinal cortex thickness and postmortem neuropathological measures. MATERIALS AND METHODS: We evaluated 50 participants from the Rush Memory and Aging Project with antemortem structural T1-weighted MR imaging and postmortem neuropathologic assessments. Here, we focused on thickness within the entorhinal cortex as anatomically defined by our previously developed MR imaging parcellation system (Desikan-Killiany Atlas in FreeSurfer). Using linear regression, we evaluated the association between entorhinal cortex thickness and tangles and amyloid-ß load within the entorhinal cortex and medial temporal and neocortical regions. RESULTS: We found a significant relationship between antemortem entorhinal cortex thickness and entorhinal cortex (P = .006) and medial temporal lobe tangles (P = .002); we found no relationship between entorhinal cortex thickness and entorhinal cortex (P = .09) and medial temporal lobe amyloid-ß (P = .09). We also found a significant association between entorhinal cortex thickness and cortical tangles (P = .003) and amyloid-ß (P = .01). We found no relationship between parahippocampal gyrus thickness and entorhinal cortex (P = .31) and medial temporal lobe tangles (P = .051). CONCLUSIONS: Our findings indicate that entorhinal cortex-associated in vivo cortical thinning may represent a marker of postmortem medial temporal and neocortical Alzheimer disease pathology.

Focal neurological deficits and West Nile virus infection.

Our experience with West Nile virus infection revealed that 54% of 28 patients had a focal neurological deficit at presentation. A meningitis or encephalitis syndrome was absent in 47% of patients with focal deficits. Details of the variety of deficits, the time to development of deficits, and the associated radiological and laboratory findings are also discussed in the present report.

MRI-derived entorhinal volume is a good predictor of conversion from MCI to AD.

With high-resolution quantitative magnetic resonance imaging (MRI) techniques, it is possible to examine alterations in brain anatomy in vivo and to identify regions affected in the earliest stages of Alzheimer's disease (AD). In the present study, 27 patients diagnosed with mild cognitive impairment (MCI) received a high-resolution MRI scan at baseline and were followed with yearly clinical evaluations. Ten of the 27 patients converted to AD during a 36-month period following the baseline clinical evaluation. Hippocampal and entorhinal cortex volumes derived from the baseline scan were compared to determine which of these two regions, known to be pathologically involved very early in the course of AD, could best differentiate MCI converters from non-converters. Although both entorhinal and hippocampal volumes were found to be independent predictors of the likelihood of conversion to AD, it was the right hemisphere entorhinal volume that best predicted conversion with a concordance rate of 93.5%.

Acute orthostatic hypotension when starting dopamine agonists in Parkinson's disease.

OBJECTIVE: To study the frequency and severity of acute orthostatic hypotension (OH) in patients with Parkinson's disease who are starting dopamine agonist therapy. PATIENTS AND METHODS: In the context of an outpatient clinical practice, 29 consecutive patients with Parkinson's disease who were starting dopamine agonist therapy were brought into the clinic for their first dose of agonist. After a baseline supine and standing blood pressure assessment, patients were given a test dose of either pergolide mesylate (0.025, 0.05, 0. 125, or 0.25 mg), pramipexole dihydrochloride (0.125 mg), or ropinirole hydrochloride (0.125 or 0.25 mg). At 3 selected times, blood pressure readings were repeated in the supine and standing positions. MAIN OUTCOME MEASURE: Orthostatic hypotension was defined as a drop in either systolic blood pressure of more than 25 mm Hg or diastolic pressure of more than 10 mm Hg. Patients with OH before the administration of the dopamine agonist were excluded. RESULTS: Ten subjects (34%) met the criteria for acute OH. There was no evidence that OH was related to the use of a specific dopamine agonist or the concurrent use of levodopa. Of the patients who met the criteria for OH, only 3 (30%) had symptoms of OH, such as lightheadedness or general malaise. CONCLUSIONS: Acute OH occurs frequently when starting dopamine agonist therapy in Parkinson's disease, but is frequently not appreciated by patients. Knowledge of acute blood pressure responses may be useful when making decisions regarding agonist titration schedules in clinical practice. Arch Neurol. 2000;57:1461-1463

Genetic variation analysis in parkinson disease patients with and without hallucinations: case-control study.

BACKGROUND: Visual hallucinations in Parkinson disease (PD) occur in approximately one third of patients treated long-term with dopaminergic medications. In Alzheimer disease, hallucinations and psychosis have been linked to increased representations of B2/B2 homozyogotes for the dopamine receptor gene DRD1 and 1/1 or 2/2 homozygotes for DRD3. In addition, a previous study of PD patients with and without hallucinations did not show differences in D2 and D3 polymorphisms, although careful case-control matching was not performed. Another study linked the apolipoprotein E4 (APOE4) allele to hallucinations in PD. OBJECTIVE: To determine whether the frequency of dopamine receptor genetic variants and APOE alleles in patients with PD with and without chronic visual hallucinations resembles the pattern previously documented in patients with Alzheimer disease. METHODS: We conducted a case-control study of 44 patients with PD and chronic hallucinations and 44 patients with PD who had never hallucinated. Cases and controls were matched for current age and medications. DNA was isolated from blood samples and assayed for DRD1, DRD2, DRD3, DRD4, and APOE polymorphisms. Receptor polymorphisms were genotyped by polymerase chain reaction. Genotypes in hallucinators and nonhallucinators were compared using Mantel-Haenszel tests stratified by pair, and allele frequencies were compared using Wilcoxon signed rank tests within pairs. RESULTS: Neither D1 receptor genotypes (P =.37) nor allele frequencies (P =.38) differed, and there was no predominance of B2/B2 homozygotes in the hallucinators. For D3, there was a higher frequency of allele 2 (P =.047), but there was no significant difference between frequencies of homozygotes vs heterozygotes (P =.39) as reported in Alzheimer disease. D4 receptor distribution of long and short alleles did not differ between the 2 patient groups, and there were too few C alleles (3 of 86) to compare D2 allele genotypes or frequencies. For APOE, 12 cases and 12 controls carried E4 alleles (P>.99). CONCLUSIONS: With careful case-control matching, visual hallucinations in PD are not associated with the pattern seen for patients with Alzheimer disease and visual hallucinations. Furthermore, there was no association between hallucinations and APOE. Similar methods using larger sample sizes might be adapted to test whether specific dopaminergic receptor genetic variants are associated with visual hallucinations in PD. Based on our data, the DRD3 allele 2 may merit further study.

Early morning off-medication dyskinesias, dystonia, and choreic subtypes.

BACKGROUND: Abnormal involuntary movements (dyskinesias) are common in patients with Parkinson disease (PD) as a consequence of the disease and dopaminergic replacement therapy. Early morning off-medication choreic dyskinesias have been recently reported after fetal dopaminergic cell transplantations in patients with advanced PD. OBJECTIVE: To determine the frequency and severity of the early morning off-medication dyskinesias in consecutive patients with advanced PD and an insufficient response to medical management before they undergo neurosurgery. METHODS: Consecutive patients with advanced idiopathic PD were examined and videotaped before undergoing neurosurgery that included pallidotomy, fetal transplantation, or deep brain stimulation. The examination took place in the morning in the practically defined off state, at least 12 hours after the last dose of dopaminergic drugs. Parkinson disease was characterized using the Unified Parkinson's Disease Rating Scale and the Hoehn and Yahr stage. Dyskinesias were rated with the Abnormal Involuntary Movements Scale and the Rush Dyskinesia Rating Scale. Patients' characteristics and medications were compared using the Wilcoxon rank sum and the Fisher exact tests. RESULTS: Of 68 consecutive patients (44 [65%] men and 24 [35%] women), 11 (16%) had early morning off-medication dyskinesia, with a 95% upper confidence limit of 24%. Focal dystonia was the most common off-medication dyskinesia, and occurred in 10 patients (15%), with a 95% upper confidence limit of 22%; and off-choreic dyskinesia occurred in 1 patient (1.5%), with a 95% upper confidence limit of 4%. There was no difference in PD medications between the patients with and those without dyskinesias. CONCLUSIONS: The most common form of off-medication dyskinesia seen in patients with advanced PD is dystonia. Early morning off-medication choreic dyskinesias are rare but do occur in patients with advanced PD before surgical intervention. The presence and type of off-medication dyskinesias should be monitored in clinical and surgical studies in patients with PD as part of the safety and evaluation of clinical benefits.

Objective changes in motor function during placebo treatment in PD.

OBJECTIVE: To examine the frequency, temporal development, and stability of objectively derived motor changes during placebo treatment in PD and to define the clinical domains and demographic groups most affected. BACKGROUND: Placebo effects are documented in neurology, but the timing and specific disabilities most susceptible to changes during placebo treatment in PD have not been examined. METHODS: The authors examined the placebo-treated group from a randomized, multicenter, placebo-controlled clinical trial of monotherapy ropinerole in PD patients without motor fluctuations. In 105 patients, they evaluated placebo-associated effects on the motor section of the Unified Parkinson's Disease Rating Scale (UPDRS), dividing the motor examination into four categories: tremor, bradykinesia, rigidity, and gait/balance/midline functions. The motor UPDRS and its subscales were compared over time (at baseline and at 4, 12, and 24 weeks) using Wilcoxon's signed rank test. They applied a rigorous definition of placebo-associated improvement as an improvement over baseline score in motor UPDRS of at least 50% or a change in at least two motor items at any one visit by > or =2 points. RESULTS: During the 6-month study, 16% of subjects improved on placebo treatment. The prevalence of response was steady (8 to 9%) at any one visit without a predominance of an early effect. No patient showed a placebo-associated improvement on all visits. All domains of parkinsonian disability were subject to placebo-associated improvement, with a trend toward more response in bradykinesia and rigidity than in tremor or gait/balance/midline function. Gender, age, disease duration, and baseline disability score did not influence the likelihood of improvement in association with placebo treatment. CONCLUSION: Based on a rigorous definition of placebo-associated improvement, prominent improvements in objective measures of PD disability occur during clinical trials. Because placebo-associated improvements occur throughout a 6-month trial, placebo-controlled studies in PD should be at least 6 months to capture early as well as late improvements.

Olanzapine and clozapine: comparative effects on motor function in hallucinating PD patients.

OBJECTIVE: To compare olanzapine and clozapine for safety and efficacy measures of psychosis and motor function in patients with PD and chronic hallucinations. BACKGROUND: Hallucinations occur in approximately one third of patients with PD treated chronically with dopaminergic drugs. Although clozapine is known to be an effective antipsychotic agent that does not significantly exacerbate parkinsonism, its use requires frequent blood count assessment. Olanzapine is another novel antipsychotic that is not associated with blood dyscrasia, and if equally effective could become the preferred drug for treating hallucinations in subjects with PD. METHODS: A randomized, double-blind, parallel comparison of olanzapine and clozapine in patients with PD with chronic hallucinations was conducted. The primary outcome measure was the Scale for the Assessment of Positive Symptoms (SAPS) for psychotic symptoms. The Unified Parkinson's Disease Rating Scale (UPDRS) motor subscale was used as a secondary outcome measure and as a safety monitoring tool. RESULTS: After 15 patients had completed the study, safety stopping rules were invoked because of exacerbated parkinsonism in olanzapine-treated subjects. UPDRS motor impairment scores from baseline to study end significantly increased with olanzapine treatment, and change scores between the olanzapine and clozapine groups significantly differed. The primary clinical domains responsible for the motor decline were gait and bradykinesia. Even with a smaller patient number than originally anticipated, clozapine significantly improved hallucinations and overall behavioral assessment, whereas olanzapine had no effect. CONCLUSIONS: At the doses studied, olanzapine aggravates parkinsonism in comparison with clozapine and should not be regularly used in the management of hallucinations in patients with PD.

Prospective longitudinal assessment of hallucinations in Parkinson's disease.

OBJECTIVE: To monitor the evolution of hallucinations over 4 years in a stratified sample of patients with PD. METHODS: Using a modified version of the Unified PD Rating Scale (UPDRS) Thought Disorder question, the authors stratified patients into five baseline behavioral groups. They recruited up to 20 patients for each group to participate in sequential interviews (Rush Hallucination Inventory) at baseline and 6, 18, and 48 months. UPDRS motor examinations and Mini Mental State Examinations (MMSE) were obtained at baseline and 48 months. Data were analyzed with Wilcoxon rank sum tests, Mantel-Haenszel tests, and Spearman correlations. To determine features that influenced the new development of hallucinations, a cumulative logit regression model of hallucination severity over time was fit using generalized estimating equations. RESULTS: Based on the design stratification, 60 patients had no hallucinations at baseline (20 with no behavioral problems, 20 with sleep fragmentation, 20 with altered dream phenomena). Twenty-nine patients had hallucinations (20 with retained insight and 9 with loss of insight). At 48 months, the authors could account for all but two subjects (98% retrieval). In 4 years, the presence of hallucinations increased (33% at baseline, 44% at 18 months, and 63% at 48 months, p < 0.0001). The presence of frequent hallucinations (at least three times weekly) also increased (p = 0.0002). Having hallucinations at baseline or at any given assessment was a strong predictor at all follow-up evaluations of continued hallucinations (p < 0.0001). Hallucinations were not associated with increased mortality (chi(2) = 0.59, df (1), p = 0.47). Among the 60 subjects without hallucinations at baseline, time was the only significant factor influencing the development of hallucination over 48 months. Baseline age, PD duration, sex, medications, and UPDRS or MMSE scores did not influence the incidence of hallucinations. CONCLUSIONS: This prospective, longitudinal study documents the persistent and progressive nature of hallucinations in PD patients on chronic dopaminergic therapy. The consistent association of hallucinations with combined levodopa/agonist therapy suggests that these drugs may play a role in the pathophysiology of hallucinations.

Effects of central dopaminergic stimulation by apomorphine on speech in Parkinson's disease.

OBJECTIVE: To determine the effect of central dopaminergic stimulation with apomorphine on speech in PD. BACKGROUND: Most patients with PD have a speech disorder. Of those, 89% have involvement of laryngeal function, and 45% have additional articulatory dysfunction. The effect of dopaminergic medications on these two dimensions of speech impairment in PD has not been selectively studied. METHODS: In a randomized, double-blind, placebo-controlled crossover design, patients with PD and speech impairment, Hoehn and Yahr stages 2 to 4 "off," and without severe dyskinesias were given placebo or apomorphine injections 0.05 mg/kg subcutaneously during two consecutive outpatient visits. They were pretreated with domperidone for 48 hours and were tested off their parkinsonian medications for 12 hours. Laryngeal function was assessed by maximum sustained vowel phonations and comfortable vowel phonations. Articulatory function was evaluated by speech intelligibility score, speaking rate, and efficiency ratio. RESULTS: Ten patients, mean age 73.4 years (SD = 6.6), disease duration 8.7 years (SD = 6.3), were tested. The baseline motor score on the Unified Parkinson's Disease Rating Scale (UPDRSm) and all experimental speech variables were equivalent on both placebo and apomorphine days. At a dose of apomorphine that provoked improvement in UPDRSm (p = 0.0078), no index of either laryngeal or articulatory function improved significantly after apomorphine administration. CONCLUSION: Laryngeal and articulatory speech components are not under prominent dopaminergic control in PD. Treatment regimens should focus on nondopaminergic pharmacology and other therapies.

Menstrual-related changes in motoric function in women with Parkinson's disease.

Questionnaire studies have found that parkinsonism worsens in women during the premenstrual period, when estrogen and progesterone levels are presumably at their nadir. To assess this patient-based observation and correlate motor signs with hormonal levels, the authors prospectively studied 10 menstruating women with PD in their "off" state, on 5 successive weeks. Although PD severity fluctuated during the study period, there was no significant correlation between the objective or subjective measures of parkinsonism and estrogen and progesterone levels.

Animal model of posthypoxic myoclonus: effects of serotonergic antagonists.

OBJECTIVE: To study specific serotonin (5-hydroxytryptamine [5-HT]) receptor subtype antagonists in an animal model of posthypoxic myoclonus. BACKGROUND: Although serotonergic system dysfunction is implicated in posthypoxic myoclonus, anatomic specificity and linkage to receptor subtypes are not delineated. METHODS: The authors performed a pharmacologic study to identify specific serotonin receptor subtype antagonists effective in inhibiting myoclonus in posthypoxic rats. Sprague-Dawley rats underwent cardiac arrest for 8 minutes and were resuscitated. On the day of pharmacologic testing, animals were rated every 10 minutes at -30 minutes to time 0 (drug injection) and from +60 to +150 minutes. Using a blinded methodology, animals were injected with normal saline, vehicle, or one of seven serotonin antagonists given at a dose that maintains serotonin receptor subtype specificity: WAY100135 (5-HT1A), methiothepin mesylate (5-HT1B/1D/2), mesulergine hydrochloride (5-HT2A/2B), GR 127935 (5-HT1D), SR 46349 (5-HT2), ondansetron (5-HT3), or GR 125487 (5-HT4). Drugs that produced a significant decrease in myoclonus compared with the control were studied in a dose-response study with six doses across a range from the original dose studied to 10% of that dose. RESULTS: Two drugs were significantly different from placebo: methiothepin mesylate and mesulergine hydrochloride. GR 127935 showed a trend toward reducing myoclonus. Dose-response studies showed that all doses of methiothepin mesylate and the three highest doses of mesulergine hydrochloride inhibited myoclonus effectively. CONCLUSIONS: 5-HT1B, 5-HT2A/2B, and possibly 5-HT1D receptor subtypes likely play a role in posthypoxic myoclonus. More specific 5-HT antagonists that affect these receptor subtypes are candidates for future testing in this model and in Lance-Adams syndrome.

Gender and pramipexole effects on levodopa pharmacokinetics and pharmacodynamics.

The authors studied the pharmacokinetics of levodopa (LD) with and without pramipexole (PPX) in men and postmenopausal women with PD. Patients on stable dose of carbidopa/LD were randomized to receive escalating doses of placebo or PPX over 7 weeks. LD and PPX pharmacokinetics were performed after a single test dose 25/100 of carbidopa/LD, before initiation of PPX or placebo, at 1.5 mg/d and 4.5 mg/d of PPX or placebo. Compared to men, women had greater LD bioavailability. PPX did not alter LD bioavailability, and PPX pharmacokinetics were equivalent in men and women.

The use of granulocyte colony-stimulating factor after liver transplantation.

Granulocyte colony-stimulating factor (G-CSF) increases the number of circulating granulocytes and decreases TNF production while improving survival in sepsis models. To study the effects of G-CSF administration on sepsis and rejection, 37 primary liver allograft recipients received intravenous recombinant human G-CSF (rhG-CSF; 5-10 micrograms/kg/day) for the first 7-10 days following transplantation, targeting a blood absolute granulocyte count of between 10,000 and 20,000 cells/mm3. These recipients were monitored prospectively for sepsis and rejection, as were the previous 49 primary liver allograft recipients who did not receive G-CSF. Both groups utilized identical protocol immunosuppression and standardized diagnosis and treatment of sepsis and rejection. Univariate and logistic regression analysis of risk factors for sepsis and rejection revealed no difference between the two patient groups. G-CSF-treated patients developed an increased absolute granulocyte count over time (P < 0.0001, repeated-measures analysis of variance). G-CSF-treated patients had a decreased number of sepsis episodes per patient (0.92 +/- 1.5 vs. 2.18 +/- 2.8, P < 0.02, t test), and a lower percentage of sepsis-related deaths (8% vs. 22%, P < 0.04, chi-square test). The incidence of acute rejection was decreased in the G-CSF-treated group (22% vs. 51%, P < 0.01, chi-square test). These pilot data support further investigation into G-CSF's favorable effects on sepsis and rejection.

Cognitive and motor function in patients with Parkinson's disease with and without depression.

The objective of this study was to define risk factors for depression in patients with idiopathic Parkinson's disease (PD) and to evaluate the correlation of depression with cognitive function and the primary domains of parkinsonian motor dysfunction tremor, bradykinesia, rigidity, gait and balance impairment. The risk factors for depression in patients with PD remain controversial. Several investigators have demonstrated a significant association between cognitive dysfunction and depression, but motoric and disease variables can confound this evaluation and have shown an inconsistent relation to depression. A consecutive series of 88 patients with PD were examined using the motor subscale of the Unified Parkinson's Disease Rating Scale (UPDRSm), Hoehn-Yahr stage (HY), and Hamilton Rating Scale for Depression (HRSD). Major depression was diagnosed according to the criteria in the Diagnostic and Statistic Manual of Mental Disorders, 4th edition. Gender, age, handedness, PD duration, side of PD onset, motor fluctuations, UPDRSm total score, daily Levodopa dose, and Mini-Mental State Examination score (MMSE) were analyzed using multivariate and univariate logistic regression, Fisher's Exact test, and Pearson correlations. Major depression was diagnosed in 12 patients (7.3%). Low MMSE score, axial bradykinesia, gait and balance impairment were strongly significant predictors of depression. In conclusion, depression and physical function are important factors impairing the quality of life for patients with PD, and regular depression screening and treatment should focus on patients with PD who have cognitive impairment, high axial bradykinesia, gait and balance impairment.

Estrogen supplementation in the posthypoxic myoclonus rat model.

The objective of the study was to investigate the effects of estrogen on severity and duration of myoclonus in the rat cardiac arrest model of posthypoxic myoclonus. Female sex hormones affect a variety of movement disorders and alter dopaminergic and serotonergic pharmacology. Although women represented three-fourths of patients from the original report of Lance and Adams and 80% of the largest published series, the impact of estrogens on myoclonus has never been studied. Twelve previously ovariectomized female rats underwent 8 minutes of mechanically induced cardiac arrest and were resuscitated according to a standardized protocol. On the same day, they were randomly assigned to subcutaneous treatment with a 21-day, 0.5-mg, 17 beta-estradiol or matching placebo pellet. Animals were tested daily with 7 sets of 45 auditory stimuli for 10 days, and myoclonus scores were obtained using a 5-point interval scale. Comparisons were based on two-sample Wilcoxon rank-sum tests. Estrogen treatment significantly enhanced myoclonus intensity and duration: mean peak myoclonus score, 210.2 +/- 18.0 versus 180 +/- 28.5 (p = 0.031); mean number of days above baseline, 9.2 +/- 0.4 versus 5.7 +/- 2.3 (p = 0.004); mean score on day 10, 90.7 +/- 38.7 versus 27.0 +/- 20.6 (p = 0.016). All estrogen-treated animals were above baseline on day 10 compared with none in the placebo group. Estrogen enhances and prolongs posthypoxic myoclonus, suggesting that female gender and estrogen status may play a pivotal role as a risk factor for human posthypoxic myoclonus.