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Inuit communities in Northern Quebec (Canada) are exposed to environmental contaminants, particularly to mercury, lead and polychlorinated biphenyls (PCBs). Previous studies reported adverse associations between these neurotoxicants and memory performance. Here we aimed to determine the associations of pre- and postnatal exposures to mercury, lead and PCB-153 on spatial navigation memory in 212 Inuit adolescents (mean age = 18.5 years) using a computer task which requires learning the location of a hidden platform based on allocentric spatial representation. Contaminant concentrations were measured in cord blood at birth and blood samples at 11 years of age and at time of testing. Multivariate regression models showed that adolescent mercury and prenatal PCB-153 exposures were associated with poorer spatial learning, whereas current exposure to PCB-153 was associated with altered spatial memory retrieval at the probe test trial. These findings suggest that contaminants might be linked to different aspects of spatial navigation processing at different stages.

Purpose: To date, research on effects of prenatal alcohol exposure (PAE) has focused on a broad range of cognitive impairments, but relatively few studies have examined effects of PAE on development of reading skills. Although PAE has been linked to poorer reading comprehension, it remains unclear whether this impairment is attributable to deficits in phonological processing, word reading, oral language skills, and/or executive functioning. Methods: A comprehensive reading battery was administered to 10 adolescents with fetal alcohol syndrome (FAS); 16 with partial FAS; 30 nonsyndromal heavily exposed; 49 controls. Results: PAE was related to poorer reading comprehension but not to singleword reading or phonological processing, suggesting that the mechanics of reading are intact in adolescents with fetal alcohol spectrum disorders at this age. PAE-related impairment in reading comprehension was mediated, in part, by deficits in mastery of oral language skills, including vocabulary, language structure, and verbal fluency. Conclusions: These results are consistent with research showing that reading comprehension in adolescence relies increasingly on linguistic comprehension abilities, especially once word reading becomes automatic and text complexity increases. Our findings suggest that reading-impaired adolescents with PAE will benefit from intervention programs targeting vocabulary knowledge, language structure, verbal fluency, and reading comprehension skills.

This study was designed to correlate clinical findings with the extent of pathologic a-synuclein (aSyn) in the brain using the Unified Staging System for Lewy Body disorders (USSLB). Data from 280 cases from the Arizona Study of Aging and Neurodegenerative Disorders are presented. Each case had a complete USSLB staging and at least 1 full research clinical assessment, including subspecialty neurologist-administered movement and cognitive evaluation. Of the 280, 25.7% were cognitively normal, 8.6% had mild cognitive impairment, and 65.7% had dementia. All cases could be categorized into 1 of 5 USSLB stages (8.6% stage I-olfactory bulb only; 15.4% IIa-brainstem predominant; 13.6% IIb-limbic predominant; 31.8% III-brainstem and limbic; and 30.7% IV-neocortical) yet using the Braak staging system 70 cases (25.3%) could not be classified. Those with USSLB stages III and IV died at a younger age. Multiple measures of motor parkinsonism, cognitive impairment, hyposmia, and probable RBD were significantly correlated with increasing USSLB stage. We conclude that the USSLB is the most comprehensive staging system for all Lewy body disorders and allows for categorization and ranking of all brains with significant correlations to many motor and nonmotor clinical signs and symptoms.

ObjectiveIdentify clinical features predictive of Lewy body pathology in Alzheimer's disease (AD) patients in an ongoing longitudinal clinicopathologic study.Material and methodsWe queried the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND) database for dementia cases with AD pathology (1997-2015). Subjects received longitudinal comprehensive clinical evaluations including motor/neuropsychological assessment and Apo-E4 genotyping. All cases were autopsied and had standard neuropathological assessments for AD and Lewy-type synucleinopathy (LTS). Subjects were categorized based on standardized pathological criteria with AD cases that had LTS but did not meet DLB pathologic criteria being categorized as ADLB. We performed pairwise comparison between the different diagnoses and multivariable modelling to identify clinical symptoms that predict the pathological diagnosis.ResultsWe identified 32 DLB/AD, 54 ADLB, 70 AD only and 41 PDD/AD cases. AD subjects with LTS pathology had higher UPDRS II and III total scores as well as generally higher individual scores compared to AD alone. While depression scales and Trail-making Test A correlated significantly with LTS, other neuropsychological variables were not significantly different. Apo E4 occurrence was similar in all groups (40%-49%).ConclusionsOur study suggests that the presence (or absence) of LTS influences motor and non-motor clinical findings in AD patients. These findings may lead to biomarkers that allow for more targeted treatment of AD.

While benchmark dose (BMD) methodology is well‐established for settings with a single exposure, these methods cannot easily handle multidimensional exposures with nonlinear effects. We propose a framework for BMD analysis to characterize the joint effect of a two‐dimensional exposure on a continuous outcome using a generalized additive model while adjusting for potential confounders via propensity scores. This leads to a dose–response surface which can be summarized in two dimensions by a contour plot in which combinations of exposures leading to the same expected effect are identified. In our motivating study of prenatal alcohol exposure, cognitive deficits in children are found to be associated with both the frequency of drinking as well as the amount of alcohol consumed on each drinking day during pregnancy. The general methodological framework is useful for a broad range of settings, including combinations of environmental stressors, such as chemical mixtures, and in explorations of the impact of dose rate rather than simply cumulative exposure on adverse outcomes. [ABSTRACT FROM AUTHOR]

Benchmark dose analysis aims to estimate the level of exposure to a toxin associated with a clinically significant adverse outcome and quantifies uncertainty using the lower limit of a confidence interval for this level. We develop a novel framework for benchmark dose analysis based on monotone additive dose-response models. We first introduce a flexible approach for fitting monotone additive models via penalized B-splines and Laplace-approximate marginal likelihood. A reflective Newton method is then developed that employs de Boor's algorithm for computing splines and their derivatives for efficient estimation of the benchmark dose. Finally, we develop a novel approach for calculating benchmark dose lower limits based on an approximate pivot for the nonlinear equation solved by the estimated benchmark dose. The favorable properties of this approach compared to the Delta method and a parameteric bootstrap are discussed. We apply the new methods to make inferences about the level of prenatal alcohol exposure associated with clinically significant cognitive defects in children using data from six NIH-funded longitudinal cohort studies. Software to reproduce the results in this paper is available online and makes use of the novel semibmd  R package, which implements the methods in this paper. [ABSTRACT FROM AUTHOR]

Background: Fetal alcohol spectrum disorders (FASD) include a range of neurocognitive and behavioral impairments resulting from prenatal alcohol exposure (PAE). Among the PAE‐related cognitive deficits, number processing is particularly affected. This study examines alterations in number processing networks and whether changes in functional connectivity mediate the adverse effects of PAE on arithmetic performance. Methods: Magnetic resonance imaging (MRI) was acquired in 57 children (mean (SD) age = 11.3 (+0.9) yr), 38 with FASD (19 fetal alcohol syndrome (FAS) or partial FAS (PFAS), 19 heavily exposed (HE)) and 19 controls. Whole‐brain correlation analyses were performed from five seeds located in regions involved in number processing. Results: Children with FAS/PFAS showed dose‐dependent reductions in resting state functional connectivity between the seed in the right (R) posterior superior parietal lobule and a cluster in the left (L) inferior frontal gyrus, and between a seed in the R horizontal intraparietal sulcus and clusters in the R precentral gyrus and L cerebellar lobule VI. HE children showed lower resting state functional connectivity in a subset of these regions. Lower functional connectivity in the two fronto‐parietal connections partially mediated the adverse effects of PAE on arithmetic performance. Conclusion: This study demonstrates PAE‐related functional connectivity impairments in functional networks involved in number processing. The weaker connectivity between the R posterior superior parietal lobule and the L inferior frontal gyrus suggests that impaired verbal processing and visuospatial working memory may play a role in number processing deficits, while weaker connectivity between the R intraparietal sulcus and the R precentral gyrus points to poorer finger‐based numerical representation, which has been linked to arithmetic computational skills. [ABSTRACT FROM AUTHOR]

Children with fetal alcohol spectrum disorders (FASD) may exhibit craniofacial dysmorphology, neurobehavioral deficits, and reduced brain volume. Studies of cortical thickness in FASD have yielded contradictory findings, with 3 reporting thicker cerebral cortex in frontal and temporal brain regions and 2 showing thinner cortex across multiple regions. All 5 studies included subjects spanning a broad age range, and none have examined continuous measures of prenatal alcohol exposure. We investigated the relation of extent of in utero alcohol exposure to cortical thickness in 78 preadolescent children with FASD and controls within a narrow age range. A whole-brain analysis using FreeSurfer revealed no significant clusters where cortical thickness differed by FASD diagnostic group. However, alcohol dose/occasion during pregnancy was inversely related to cortical thickness in 3 regions-right cuneus/pericalcarine/superior parietal lobe, fusiform/lingual gyrus, and supramarginal/postcentral gyrus. The effect of prenatal alcohol exposure on IQ was mediated by cortical thickness in the right occipitotemporal region. It is noteworthy that a continuous measure of maternal alcohol consumption during pregnancy was more sensitive than FASD diagnosis and that the effect on cortical thickness was most evident in relation to a measure of maternal binge drinking.

BackgroundAlthough there are studies investigating the pathologic origins of mild cognitive impairment (MCI), they have revolved around comparisons to normal elderly individuals or those with Alzheimer's disease (AD) or other dementias. There are few studies directly comparing the comprehensive neuropathology of amnestic (aMCI) and nonamnestic (naMCI) MCI.MethodsThe database of the Brain and Body Donation Program ( www.brainandbodydonationprogram.org ), a longitudinal clinicopathological study of normal aging and neurodegenerative disorders, was queried for subjects who were carrying a diagnosis of aMCI or naMCI at the time of autopsy. Neuropathological lesions, including neuritic plaques, neurofibrillary tangles (NFTs), Lewy bodies (LBs), infarcts, cerebral white matter rarefaction (CWMR), cerebral amyloid angiopathy (CAA), and concurrent major clinicopathological diagnoses, including Parkinson's disease (PD) were analyzed.ResultsThirty four subjects with aMCI and 15 naMCI met study criteria. Subjects with aMCI were older at death (88 vs. 83 years of age, p = 0.03). Individuals with naMCI had higher densities of LBs within the temporal lobe (p = 0.04) while subjects with aMCI had a propensity for increased NFTs in parietal and temporal lobes (p values = 0.07). After adjusting for age at death, the only significant difference was greater densities of temporal lobe NFTs within the aMCI group. Other regional pathology scores for plaques, NFTs, and LBs were similar between groups. Subjects met clinico-pathological criteria for co-existent PD in 24 % aMCI and 47 % naMCI while neuropathological criteria for AD were met in equal percentages of aMCI and of naMCI cases (53 %); these proportional differences were not significant (p values > 0.35). Furthermore, regardless of amnestic status, there was a greater presence of CAA (71 % of MCI with executive dysfunction vs. 39 % without p = 0.03) and a greater presence of CWMR (81 % of MCI with executive dysfunction and 54 % without p = 0.046) in MCI cases with executive dysfunction.ConclusionsNo single pathologic entity strongly dichotomized MCI groups, perhaps due to the pathologic heterogeneity found within both entities. However, these data suggest the possibility for naMCI to have a propensity for increased LBs and aMCI for increased NFTs in select anatomic regions.

The Brain and Body Donation Program (BBDP) at Banner Sun Health Research Institute (http://www.brainandbodydonationprogram.org) started in 1987 with brain-only donations and currently has banked more than 1600 brains. More than 430 whole-body donations have been received since this service was commenced in 2005. The collective academic output of the BBDP is now described as the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND). Most BBDP subjects are enrolled as cognitively normal volunteers residing in the retirement communities of metropolitan Phoenix, Arizona. Specific recruitment efforts are also directed at subjects with Alzheimer's disease, Parkinson's disease and cancer. The median age at death is 82. Subjects receive standardized general medical, neurological, neuropsychological and movement disorders assessments during life and more than 90% receive full pathological examinations by medically licensed pathologists after death. The Program has been funded through a combination of internal, federal and state of Arizona grants as well as user fees and pharmaceutical industry collaborations. Subsets of the Program are utilized by the US National Institute on Aging Arizona Alzheimer's Disease Core Center and the US National Institute of Neurological Disorders and Stroke National Brain and Tissue Resource for Parkinson's Disease and Related Disorders. Substantial funding has also been received from the Michael J. Fox Foundation for Parkinson's Research. The Program has made rapid autopsy a priority, with a 3.0-hour median post-mortem interval for the entire collection. The median RNA Integrity Number (RIN) for frozen brain and body tissue is 8.9 and 7.4, respectively. More than 2500 tissue requests have been served and currently about 200 are served annually. These requests have been made by more than 400 investigators located in 32 US states and 15 countries. Tissue from the BBDP has contributed to more than 350 publications and more than 200 grant-funded projects.

ObjectivePrevious research has linked complex or formed visual hallucinations (VH) to Lewy-type alpha-synucleinopathy (LTS) in neocortical and limbic areas. As Alzheimer's disease pathology often co-occurs with LTS, we questioned whether this pathology - amyloid plaques and neurofibrillary tangles - might also be linked to VH.MethodsWe performed a semi-quantitative neuropathological study across brainstem, limbic, and cortical structures in subjects with a documented clinical history of VH and a clinicopathological diagnosis of Parkinson's disease (PD), Alzheimer's disease (AD), or dementia with Lewy bodies (DLB). 173 subjects - including 50 with VH and 123 without VH - were selected from the Arizona Study of Aging and Neurodegenerative Disorders. Clinical variables examined included the Mini-mental State Exam, Hoehn & Yahr stage, and total dopaminergic medication dose. Neuropathological variables examined included total and regional LTS and plaque and tangle densities.ResultsA significant relationship was found between the density of LTS and the presence of VH in PD, AD, and DLB. Plaque and tangle densities also were associated with VH in PD (p = .003 for plaque and p = .004 for tangles) but not in AD, where densities were high regardless of the presence of hallucinations. Furthermore, with DLB cases excluded, comorbidity of PD and AD was significantly more prevalent among subjects + VH than subjects -VH (p < .001).ConclusionThese findings suggest that both AD and PD neuropathology contribute to the pathogenesis of VH. Incident VH could be predictive of concomitant AD/PD pathology even when criteria are not met for a second diagnosis.

ObjectivesDetermine diagnostic accuracy of a clinical diagnosis of Parkinson disease (PD) using neuropathologic diagnosis as the gold standard.MethodsData from the Arizona Study of Aging and Neurodegenerative Disorders were used to determine the predictive value of a clinical PD diagnosis, using 2 clinical diagnostic confidence levels, PossPD (never treated or not clearly responsive) and ProbPD (responsive to medications). Neuropathologic diagnosis was the gold standard.ResultsBased on first visit, 9 of 34 (26%) PossPD cases had neuropathologically confirmed PD while 80 of 97 (82%) ProbPD cases had confirmed PD. PD was confirmed in 8 of 15 (53%) ProbPD cases with 85% diagnostic accuracy of longer duration, medication-responsive PD. Caution is needed when interpreting clinical studies of PD, especially studies of early disease that do not have autopsy confirmation. The need for a tissue or other diagnostic biomarker is reinforced.Classification of evidenceThis study provides Class II evidence that a clinical diagnosis of PD identifies patients who will have pathologically confirmed PD with a sensitivity of 88% and specificity of 68%.

BACKGROUND: Animal models have demonstrated fetal alcohol-related disruptions in neuroendocrine function in the hypothalamic-pituitary-gonadal axis and downstream effects on pubertal development and sexual behavior in males and females, but little is known about these effects in humans. This study examined whether prenatal alcohol exposure is associated with alterations in testosterone during adolescence and whether it affects timing of pubertal development. METHODS: The sample consisted of 265 African American adolescents from the Detroit Longitudinal Cohort Study for whom testosterone and/or pubertal development data were available. Subjects were offspring of women recruited at their first prenatal clinic visit to over represent moderate-to-heavy alcohol use, including a 5% random sample of low-level drinkers/abstainers. Mothers were interviewed at every prenatal visit about their alcohol consumption using a timeline follow-back approach and about their smoking and drug use and sociodemographic factors. At age 14 years, adolescents provided salivary samples, which were analyzed for testosterone (pg/ml), self-reported Tanner stages for pubertal development, and age at menarche (females). RESULTS: Prenatal alcohol exposure was related to elevated testosterone concentrations for males and females but not to changes in Tanner stages or age at menarche, after controlling for confounders. In regression models stratified by alcohol exposure, the expected relation between testosterone and pubic hair development was seen among males with light-to-no prenatal alcohol exposure, but not among those with moderate-to-heavy prenatal alcohol exposure. This interaction between testosterone and prenatal alcohol exposure was confirmed in multivariable models including an alcohol exposure group × testosterone interaction term and potential confounders. CONCLUSIONS: This study is the first to show a relation between prenatal alcohol exposure and increased testosterone during adolescence and evidence of decreased testosterone responsiveness in tissues related to pubertal development in humans. Further studies examining androgen receptor expression and other hormonal and cellular factors affecting pubertal development may reveal important mechanisms underlying these teratogenic effects of alcohol exposure.

IntroductionMany clinicopathological studies do not specify the presence of other pathologies located within the brain, so disease heterogeneity may be under appreciated.ObjectiveThe purpose of this study was to determine the frequencies of concomitant pathologies among parkinsonian disorders.MethodsData from the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND), an ongoing longitudinal clinical-neuropathological study, was used to analyze concomitant pathologies, including Alzheimer's disease (AD), argyrophilic grains (Arg), cerebral amyloid angiopathy (CAA), cerebral white matter rarefaction (CWMR) and overlap of each parkinsonian disorder in clinico-pathologically defined Parkinson's disease (PD; N = 140), dementia with Lewy bodies (DLB; N = 90), progressive supranuclear palsy (PSP; N = 64), multiple system atrophy (MSA; N = 6), corticobasal degeneration (CBD; N = 7); and normal elderly (controls; N = 166).ResultsOf the neuropathologically-confirmed PD cases, 38% had a concomitant diagnosis of AD, 9% PSP, 25% Arg, 44% CWMR, and 24% CAA. For DLB, 89% had AD, 1% PSP, 21% Arg, 51% CWMR, and 50% CAA. For PSP cases, 36% had AD, 20% PD, 1% DLB, 44% Arg, 52% CWMR and 25% CAA. Similar heterogeneity was seen for MSA and CBD cases. Many cases had more than one of the above additional diagnoses.ConclusionsThese data demonstrate a great deal of concomitant pathologies among different types of parkinsonian disorders; this may help explain the heterogeneity of clinical findings.

Existing reports on the frequencies of neurodegenerative diseases are typically based on clinical diagnoses. We sought to determine these frequencies in a prospectively assessed, community-based autopsy series. Included subjects had normal cognitive and movement disorder assessments at study entry. Of the 119 cases meeting these criteria, 52% were women; the median age of study entry was 83.5 years (range, 67-99 years), and the median duration from the first visit until death was 4.3 years (range, 0-10 years). At autopsy, clinicopathological diagnoses were made in 30 cases (25%). These diagnoses included 20 with Alzheimer disease (AD) (17%), 7 with vascular dementia (6%), 4 with progressive supranuclear palsy (3%), 3 with Parkinson disease and 1 each with dementia with Lewy bodies, corticobasal degeneration, or multiple system atrophy (0.8% each). Of the 87 subjects still clinically normal at death (73%), 33 had extensive AD pathology (preclinical AD) (38%), 17 had incidental Lewy bodies (20%), and 4 had incidental pathology consistent with progressive supranuclear palsy (5%). The diagnoses were not mutually exclusive. Although limited by a relatively small sample size, the neuropathological outcome of these initially normal elderly subjects represents a rough estimate of the incidence of these neurodegenerative conditions over a defined time period.

Background: A better understanding of the effects of lower levels of prenatal alcohol exposure (PAE), as a common exposure, is needed. The goal of this study was to examine the effects of mild-moderate PAE and episodic binge drinking on perinatal outcomes. Methods: The data were obtained from three prospective cohorts with a combined sample of 281 participants: 125 with PAE and 156 without PAE. Alcohol-related measures included the Alcohol Use Disorders Identification Test, timeline follow-back questionnaires (covering the periconceptional period, mid-gestation, and late gestation), and biomarkers. Absolute alcohol per day (AAD) and per drinking day (AADD), number of binge episodes, and maximum number of drinks in a 24-h period were estimated. Perinatal outcomes included gestational age and anthropometric measures. Data were analyzed using correlation and multivariable regression analysis. Results: Among women with PAE, average alcohol consumption across the periconceptional period and pregnancy was 0.37 oz ± 0.74 AA/day (~5 drinks/week). After adjusting for tobacco co-exposure and sociodemographic characteristics, significant associations between all alcohol measures and gestational age at delivery were observed, including cumulative measures of AAD (β = -0.58; 95% CI: -0.98; -0.17) and AADD (β = -0.58; 95% CI: -0.90; -0.26) during pregnancy and the periconceptional period. A significant association between the maximum number of drinks in a 24-h period and birth length percentile (β = -0.70; 95% CI: -1.36; -0.04) was observed in the final model. PAE was associated with lower birth weight percentile in univariate analyses only. Conclusions: Results of this study demonstrate a negative association between mild-moderate PAE and episodic binge drinking with gestational age at delivery and birth length percentile after controlling for other factors. Robust negative effects of PAE, including in the periconceptional period before pregnancy recognition, on duration of gestation highlight the need for primary prevention efforts aimed at PAE in persons of reproductive age. [ABSTRACT FROM AUTHOR]

Background: Most studies of the effects of prenatal alcohol exposure (PAE) on cognitive function have assumed that the dose-response curve is linear. However, data from a few animal and human studies suggest that there may be an inflection point in the dose-response curve above which PAE effects are markedly stronger and that there may be differences associated with pattern of exposure, assessed in terms of alcohol dose per drinking occasion and drinking frequency. Methods: We performed second-order confirmatory factor analysis on data obtained at school age, adolescence, and early adulthood from 2227 participants in six US longitudinal cohorts to derive a composite measure of cognitive function. Regression models were constructed to examine effects of PAE on cognitive function, adjusted for propensity scores. Analyses based on a single predictor (absolute alcohol (AA)/day) were compared with analyses based on two predictors (dose/occasion and drinking frequency), using (1) linear models and (2) nonparametric general additive models (GAM) that allow for both linear and nonlinear effects. Results: The single-predictor GAM model showed virtually no nonlinearity in the effect of AA/day on cognitive function. However, the two-predictor GAM model revealed differential effects of maternal drinking pattern. Among offspring of infrequent drinkers, PAE effects on cognitive function were markedly stronger in those whose mothers drank more than ~3 drinks/occasion, and the effect of dose/occasion was strongest among the very frequent drinkers. Frequency of drinking did not appear to alter the PAE effect on cognitive function among participants born to mothers who limited their drinking to ~1 drink/occasion or less. Conclusions: These findings suggest that linear models based on total AA/day are appropriate for assessing whether PAE affects a given cognitive outcome. However, examination of alcohol dose/occasion and drinking frequency is needed to fully characterize the impact of different levels of alcohol intake on cognitive impairment. [ABSTRACT FROM AUTHOR]

Prenatal alcohol exposure (PAE) and prenatal stress (PS) are highly prevalent conditions known to affect fetal programming of the hypothalamic-pituitary-adrenal (HPA) axis. The objectives of this study were to assess the effect of light PAE, PS, and PAE-PS interaction on fetal HPA axis activity assessed via placental and umbilical cord blood biomarkers. Participants of the ENRICH-2 cohort were recruited during the second trimester and classified into the PAE and unexposed control groups. PS was assessed by the Perceived Stress Scale. Placental tissue was collected promptly after delivery; gene and protein analysis for 11β-HSD1, 11β-HSD2, and pCRH were conducted by qPCR and ELISA, respectively. Umbilical cord blood was analyzed for cortisone and cortisol. Pearson correlation and multivariable linear regression examined the association of PAE and PS with HPA axis biomarkers. Mean alcohol consumption in the PAE group was ~2 drinks/week. Higher PS was observed in the PAE group (p < 0.01). In multivariable modeling, PS was associated with pCRH gene expression (β = 0.006, p < 0.01), while PAE was associated with 11β-HSD2 protein expression (β = 0.56, p < 0.01). A significant alcohol-by-stress interaction was observed with respect to 11β-HSD2 protein expression (p < 0.01). Results indicate that PAE and PS may independently and in combination affect fetal programming of the HPA axis. [ABSTRACT FROM AUTHOR]

BackgroundCarriers of the ApoE ϵ4 allele are at a greater risk for developing Alzheimer's disease (AD) and those who do develop AD tend to have a much greater neuropathological disease burden. Although several studies have shown significant differences in AD pathology among ϵ4 carriers and non-carriers, few have characterized these differences in terms of brain region and neuropathological score frequency.Methods566 pathologically-confirmed AD cases who were followed prospectively with antemortem dementia diagnoses (312 ApoE ϵ4 carriers and 254 ApoE ϵ4 non-carriers) were compared on the frequencies of neuropathological frequency scores (none, sparse, moderate, frequent) among several different brain regions (frontal, temporal, parietal, hippocampal, and entorhinal) using the CERAD scoring system. Pathology score frequencies were analyzed by carrier status (ϵ4 carrier vs. ϵ4 non-carrier) and by genotype (2/3, 3/3, 2/4, 3/4, 4/4). Both analyses investigated pathology score frequencies among different brain regions (frontal, temporal, parietal, hippocampal, and entorhinal).Resultsϵ4 carriers had a significantly lower age at death (p

Identifying biomarkers that distinguish Parkinson's disease (PD) from normal control (NC) individuals has the potential to increase diagnostic sensitivity for the detection of early-stage PD. A previous proteomic study identified potential biomarkers in postmortem ventricular cerebrospinal fluid (V-CSF) from neuropathologically diagnosed PD subjects lacking Alzheimer's disease (AD) neuropathology. In the present study, we assessed these biomarkers as well as p-tau(181), Aβ42, and S100B by ELISA in PD (n = 43) and NC (n = 49) cases. The p-tau(181)/Aβ42 ratio and ApoA-1 showed statistically significant differences between groups. Multiple regression analysis demonstrated that p-tau(181)/Aβ42 had a significant odds ratio: OR = 1.42 (95% confidence interval [CI], 1.12-1.84), P = 0.006. Among the molecules investigated, intriguing correlations were observed that require further investigation. Our results suggest coexistent AD CSF biomarkers within the PD group notwithstanding that it was selected to minimize AD neuropathological lesions.

Identifying biomarkers that distinguish Parkinsons disease (PD) from normal control (NC) individuals has the potential to increase diagnostic sensitivity for the detection of early-stage PD. A previous proteomic study identified potential biomarkers in postmortem ventricular cerebrospinal fluid (V-CSF) from neuropathologically diagnosed PD subjects lacking Alzheimers disease (AD) neuropathology. In the present study, we assessed these biomarkers as well as p-tau(181), Aβ42, and S100B by ELISA in PD (n = 43) and NC (n = 49) cases. The p-tau(181)/Aβ42 ratio and ApoA-1 showed statistically significant differences between groups. Multiple regression analysis demonstrated that p-tau(181)/Aβ42 had a significant odds ratio: OR = 1.42 (95% confidence interval [CI], 1.12-1.84), P = 0.006. Among the molecules investigated, intriguing correlations were observed that require further investigation. Our results suggest coexistent AD CSF biomarkers within the PD group notwithstanding that it was selected to minimize AD neuropathological lesions.

This study proposes an alternative to the current use of the “openness ratio” by investigating the contribution of the acoustical and visual proprerties as a result of structure shape and size to its effectiveness for deer. Reed et al. (1975) coined the term “openness” to describe and measure a concept that mule deer (Odocoileus hemionus) prefer crossing structures with a clear view of the horizon. Since then, the concept has been extrapolated far beyond Reed’s use, for all shapes of underpasses and for many species of animals, most often with no definition beyond a simplistic height x width/length. Other problems with the current use of the concept are the inconsistent use of the units (English vs metric), different terms (ratio, index or simply openness), measurements at different points on a non-square underpass, lack of differentiation between the value of height vs width, and lack of well-designed experimental studies controlling for this variable. Yet biologists intuitively know that ungulates prefer structures with good visibility, and several studies support this even without a means to clearly differentiate the contribution of openness components. This study looks at the way that different shapes and sizes of underpasses contribute to the components of an open feeling in terms of the predator avoidance adaptations of white-tailed deer (Odocoileus virginianus). Underpass shape, size and materials determine the acoustical signature of noises resonating within a structure. For example, an arch shape within the sizes often used for wildlife crossing structures will focus sound in the approximate location of a deer’s head. As underpass size increases, resonance diminishes. Underpass length deter¬mines the amount of total light and the perception of distance to the end of the structure. White-tailed deer perceive danger through hearing, vision and smell. Their use of hearing is impaired if sounds resonating from the interior of an underpass are unknown to them and mask other normal sounds, thus causing fright and possible flight. White-tailed deer perceive movement along a horizontal plane better than focused detail, and their depth perception is lower than animals with eyes facing forward. Their vision in low light conditions is far better than humans. These factors taken together can be used to redefine the Openness concept into its important components. We propose that Openness be comprised of the following four measures. 1) Aspect Ratio measures the relationship between a structure’s length and height, measured at the approximate height of a deer’s head, or 1 meter. This measure considers the greater importance of horizontal visibility for predator detection from an ungulate’s perspective. 2) Cross-sectional Area measures the area above a horizontal line at a 1 meter. This measure takes into account that structures of varying shape produce different perceptions of openness. 3) Brightness measures the perception of distance that varies with the length of a structure. This measure takes into account the perception of apparent distance to safety and flight distance. 4) Presence of a Ledge indicates presence or absence of a horizontal ledge whose surface is not visible from an animal inside the structure. This indicator considers the intimidating effect of a possible predator attack position on the willingness of deer to pass through an enclosed structure. Thresholds for these components will be proposed as alternative measures to the current use of the “Openness Ratio” for highway crossing structures intended for white-tailed deer, and suggested as further study for other ungulates as well.

Transportation planners occasionally notice a curious lack of consistency and communication between hydrologists, fisheries biologists and wildlife biologists regarding passages designed for their respective specialties. Several substantial differences in treatments between aquatic and terrestrial passages at highways masks the majority of similarities. At one end of the continuum, aquatics passages can be characterized by a total containment within a watercourse, with no need for modification of the shape or size of water conveyance structure as long as the structure maintains hydrological functionality. At the opposite end of the continuum terrestrial passages can be intentionally designed to avoid water conveyance entirely. Between these two extremes lie similarities in the need for functional streamcourses that allow passage for all age classes of fish and wildlife, as well as high water events. Our paper discusses the common mistakes made when considering only one passage category and suggests remedies designed to integrate the needs of terrestrial and aquatic organism passages. Our paper also discusses the professional basis for the occasional forgetfulness in dealing with other disciplines using lessons learned on this topic by the USDA Forest Service as an interdisciplinary land management agency.

In psychiatric and social epidemiology studies, it is common to measure multiple different outcomes using a comprehensive battery of tests thought to be related to an underlying construct of interest. In the research that motivates our work, researchers wanted to assess the impact of in utero alcohol exposure on child cognition and neuropsychological development, which are evaluated using a range of different psychometric tests. Statistical analysis of the resulting multiple outcomes data can be challenging, because the outcomes measured on the same individual are not independent. Moreover, it is unclear, a priori, which outcomes are impacted by the exposure under study. While researchers will typically have some hypotheses about which outcomes are important, a framework is needed to help identify outcomes that are sensitive to the exposure and to quantify the associated treatment or exposure effects of interest. We propose such a framework using a modification of stochastic search variable selection, a popular Bayesian variable selection model and use it to quantify an overall effect of the exposure on the affected outcomes. The performance of the method is investigated empirically and an illustration is given through application using data from our motivating study. [ABSTRACT FROM AUTHOR]