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Background: Major psychiatric diseases such as schizophrenia and mood disorders have not been linked to a specific pathology, but their clinical features overlap with some aspects of the behavioral variant of frontotemporal lobar degeneration. Although the significance of pathological 43-kDa (transactivation response) DNA-binding protein (TDP-43) for frontotemporal lobar degeneration was appreciated only recently, the prevalence of TDP-43 pathology in patients with severe mental illness vs controls has not been systematically addressed. Objective: To examine patients with chronic psychiatric diseases, mainlyschizophrenia, for evidence of neurodegenerative TDP-43 pathology in comparison with controls. Design: Prospective longitudinal clinical evaluation and retrospective medical record review, immunohistochemical identification of pathological TDP-43 in the central nervous system, and genotyping for gene alterations known to cause TDP-43 proteinopathies including the TDP-43 (TARDBP) and progranulin (GRN) genes. Setting: University health system. Participants: One hundred fifty-one subjects including 91 patients with severe mental illness (mainly schizophrenia) and 60 controls. Main Outcome Measures: Clinical medical record review, neuronal and glial TDP-43 pathology, and TARDP and GRN genotyping status. Results: Significant TDP-43 pathology in the amygdala/periamygdaloid region or the hippocampus/ transentorhinal cortex was absent in both groups in subjects younger than 65 years but present in elderly subjects (29% [25 of 86] of the psychiatric patients and 29% [10 of 34] of control subjects). Twenty-three percent (8 of 35) of the positive cases showed significant TDP-43 pathology in extended brain scans. There were no evident differences between the 2 groups in the frequency, degree, or morphological pattern of TDP-43 pathology. The latter included (1) subpial and subependymal, (2) focal, or (3) diffuse lesions in deep brain parenchyma and (4) perivascular pathology. A new GRN variant of unknown significance (c.620T>C, p.Met207Thr) was found in 1 patient with schizophrenia with TDP-43 pathology. No known TARDBP mutations or other variants were found in any of the subjects studied herein. Conclusions: The similar findings of TDP-43 pathology in elderly patients with severe mental illness and controls suggest common age-dependent TDP-43 changes in limbic brain areas that may signify that these regions are affected early in the course of a cerebral TDP-43 multisystem proteinopathy. Finally, our data provide an age-related baseline for the development of whole-brain pathological TDP-43 evolution schemata. [ABSTRACT FROM AUTHOR]

Considering a situation in which observations are made by several instruments over time, researchers are interested in estimating the true quantity at a particular time point. Assuming observations made by different instruments at the same time point have the same time-dependent mean but different variances, one approach is to estimate the true quantity or the time-dependent mean by simply averaging the observations at a time point. However, since the variability of each instrument may be very different, the unweighted average can be improved by a weighted average with weights estimated from the longitudinal measurements produced by those instruments. Such a weighted average estimator is studied in this article. It is shown to be unbiased for the true quantity. Its variance is asymptotically smaller than that of any observation and also achieves the minimum variance among all the weighted estimates with known weights. The proposed method is illustrated by a real data example. The method is not restricted to the time-dependent situation. The general setting where this method can be applied is described at the end of the article. Copyright © 2001 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: Lewy body disorders (LBD), encompassing Parkinson disease (PD), PD dementia (PDD), and dementia with Lewy bodies (DLB), are characterized by alpha-synuclein pathology but often are accompanied by Alzheimer’s disease (AD) neuropathological change (ADNC). The medial temporal lobe (MTL) is a primary locus of tau accumulation and associated neurodegeneration in AD. However, it is unclear the extent to which AD copathology in LBD (LBD/AD+) contributes to MTL-specific patterns of degeneration. We employ a MTL subregional segmentation strategy of T1-weighted (T1w) MRI in biomarker-supported or autopsy-confirmed LBD and LBD/AD+ to investigate the anatomic consequences of co-occurring LBD/AD+ pathology on neurodegeneration. Methods: We studied 167 individuals with clinical diagnoses of LBD (PD, n = 124 (74.3 %); PDD, n = 11 (6.6 %); DLB, n = 32 (19.2 %)) with available T1w MRI and AD biomarkers or autopsy evidence of ADNC. Individuals were further biologically classified as LBD/AD+ based on hierarchical evidence of ADNC pathology: 1) AD “intermediate” or “high” by ABC neuropathologic criteria (n = 39 (23.4 %)); 2) positive amyloid PET (n = 2 (1.2 %)); or 3) CSF β-amyloid1-42

Abstract INTRODUCTION We investigated the feasibility and validity of the remotely‐administered neuropsychological battery from the National Alzheimer's Coordinating Center Uniform Data Set (UDS T‐Cog). METHODS Two hundred twenty Penn Alzheimer's Disease Research Center participants with unimpaired cognition, mild cognitive impairment, and dementia completed the T‐Cog during their annual UDS evaluation. We assessed administration feasibility and diagnostic group differences cross‐sectionally across telephone versus videoconference modalities, and compared T‐Cog to prior in‐person UDS scores longitudinally. RESULTS Administration time averaged 54 min and 79% of participants who initiated a T‐Cog completed all 12 subtests; completion time and rates differed by diagnostic group but not by modality. Performance varied expectedly across groups with moderate to strong associations between most T‐Cog measures and in‐person correlates, although select subtests demonstrated lower comparability. DISCUSSION The T‐Cog is feasibly administered and shows preliminary validity in a cognitively heterogeneous cohort. Normative data from this cohort should be expanded to more diverse populations to enhance utility and generalizability. Highlights This study examined the feasibility and validity of the remote Uniform Data Set (also known as the T‐Cog) and contributes key normative data for widespread use. A remote neuropsychological battery was feasibly administered with high overall engagement and completion rates, adequate reliability compared to in‐person testing, and evidence of validity across diagnostic groups. Typical barriers to administration included hearing impairment, technology issues, and distractions; hearing difficulties were particularly common among cognitively impaired groups. Certain tests were less closely related to their in‐person correlates and should be used with caution.

Abstract Objective To determine if plasma tau phosphorylated at threonine 181 (p‐tau181) distinguishes pathology‐confirmed Alzheimer's disease (AD) from normal cognition (NC) adults, to test if p‐tau181 predicts cognitive and functional decline, and to validate findings in an external cohort. Methods Thirty‐one neuropathology‐confirmed AD cases, participants with clinical diagnoses of mild cognitive impairment (MCI, N = 91) or AD dementia (N = 64), and NC (N = 241) had plasma collected at study entry. The clinical diagnosis groups had annual cognitive (Mini‐Mental State Examination, MMSE) and functional (Clinical Dementia Rating Scale, CDR) measures. NC (N = 70), MCI (N = 75), and AD dementia (N = 50) cases from the Alzheimer's Disease Neuroimaging Initiative (ADNI) were used as a validation cohort. Plasma p‐tau181 was measured using the Quanterix SiMoA HD‐X platform. Results Plasma p‐tau181 differentiated pathology‐confirmed AD from NC with negative amyloid PET scans with an AUC of 0.93. A cut point of 3.44 pg/mL (maximum Youden Index) had a sensitivity of 0.77, specificity of 0.96. p‐Tau181 values above the cut point were associated with the faster rate of decline in MMSE in AD dementia and MCI and a shorter time to a clinically significant functional decline in all groups. In a subset of MCI cases from ADNI, p‐tau181 values above the cut point associated with faster rate of decline in MMSE, and a shorter time to a clinically significant functional decline and conversion to dementia. Interpretation Plasma p‐tau181 differentiates AD pathology cases from NC with high accuracy. Higher levels of plasma p‐tau181 are associated with faster cognitive and functional decline.

In Alzheimer’s disease (AD) tau and neurodegeneration have complex regional relationships. Here, the authors show neuronal hypometabolism discordant with tau burden defines functional resilience or susceptibility to Alzheimer’s pathology via limbic/cortical axes. Susceptible groups have faster cognitive decline and evidence of non-Alzheimer’s pathologies.

Abstract Frontotemporal lobar degeneration proteinopathies with tau inclusions (FTLD-Tau) or TDP-43 inclusions (FTLD-TDP) are associated with clinically similar phenotypes. However, these disparate proteinopathies likely differ in cellular severity and regional distribution of inclusions in white matter (WM) and adjacent grey matter (GM), which have been understudied. We performed a neuropathological study of subcortical WM and adjacent GM in a large autopsy cohort (n = 92; FTLD-Tau = 37, FTLD-TDP = 55) using a validated digital image approach. The antemortem clinical phenotype was behavioral-variant frontotemporal dementia (bvFTD) in 23 patients with FTLD-Tau and 42 with FTLD-TDP, and primary progressive aphasia (PPA) in 14 patients with FTLD-Tau and 13 with FTLD-TDP. We used linear mixed-effects models to: (1) compare WM pathology burden between proteinopathies; (2) investigate the relationship between WM pathology burden and WM degeneration using luxol fast blue (LFB) myelin staining; (3) study regional patterns of pathology burden in clinico-pathological groups. WM pathology burden was greater in FTLD-Tau compared to FTLD-TDP across regions (beta = 4.21, SE = 0.34, p

Mild cognitive impairment (MCI) can be an early manifestation of Alzheimer’s disease (AD) pathology, other pathologic entities [e.g., cerebrovascular disease, Lewy body disease, LATE (limbic-predominant age-related TDP-43 encephalopathy)], or mixed pathologies, with concomitant AD- and non-AD pathology being particularly common, albeit difficult to identify, in living MCI patients. The National Institute on Aging and Alzheimer’s Association (NIA-AA) A/T/(N) [β-Amyloid/Tau/(Neurodegeneration)] AD research framework, which classifies research participants according to three binary biomarkers [β-amyloid (A+/A-), tau (T+/T-), and neurodegeneration (N+/N-)], provides an indirect means of identifying such cases. Individuals with A+T-(N+) MCI are thought to have both AD pathologic change, given the presence of β-amyloid, and non-AD pathophysiology, given neurodegeneration without tau, because in typical AD it is tau accumulation that is most tightly linked to neuronal injury and cognitive decline. Thus, in A+T-(N+) MCI (hereafter referred to as “mismatch MCI” for the tau-neurodegeneration mismatch), non-AD pathology is hypothesized to drive neurodegeneration and symptoms, because β-amyloid, in the absence of tau, likely reflects a preclinical stage of AD. We compared a group of individuals with mismatch MCI to groups with A+T+(N+) MCI (or “prodromal AD”) and A-T-(N+) MCI (or “neurodegeneration-only MCI”) on cross-sectional and longitudinal cognition and neuroimaging characteristics. β-amyloid and tau status were determined by CSF assays, while neurodegeneration status was based on hippocampal volume on MRI. Overall, mismatch MCI was less “AD-like” than prodromal AD and generally, with some exceptions, more closely resembled the neurodegeneration-only group. At baseline, mismatch MCI had less episodic memory loss compared to prodromal AD. Longitudinally, mismatch MCI declined more slowly than prodromal AD across all included cognitive domains, while mismatch MCI and neurodegeneration-only MCI declined at comparable rates. Prodromal AD had smaller baseline posterior hippocampal volume than mismatch MCI, and whole brain analyses demonstrated cortical thinning that was widespread in prodromal AD but largely restricted to the medial temporal lobes (MTLs) for the mismatch and neurodegeneration-only MCI groups. Longitudinally, mismatch MCI had slower rates of volume loss than prodromal AD throughout the MTLs. Differences in cross-sectional and longitudinal cognitive and neuroimaging measures between mismatch MCI and prodromal AD may reflect disparate underlying pathologic processes, with the mismatch group potentially being driven by non-AD pathologies on a background of largely preclinical AD. These findings suggest that β-amyloid status alone in MCI may not reveal the underlying driver of symptoms with important implications for enrollment in clinical trials and prognosis.

A major medical challenge in the elderly is osteoporosis and the high risk of fracture. Telomere dysfunction is a cause of cellular senescence and telomere shortening, which occurs with age in cells from most human tissues, including bone. Telomere defects contribute to the pathogenesis of two progeroid disorders characterized by premature osteoporosis, Werner syndrome and dyskeratosis congenital. It is hypothesized that telomere shortening contributes to bone aging. We evaluated the skeletal phenotypes of mice with disrupted telomere maintenance mechanisms as models for human bone aging, including mutants in Werner helicase (Wrn−/−), telomerase (Terc−/−) and Wrn−/−Terc−/− double mutants. Compared with young wild-type (WT) mice, micro-computerized tomography analysis revealed that young Terc−/− and Wrn−/−Terc−/− mice have decreased trabecular bone volume, trabecular number and trabecular thickness, as well as increased trabecular spacing. In cortical bone, young Terc−/− and Wrn−/−Terc−/− mice have increased cortical thinning, and increased porosity relative to age-matched WT mice. These trabecular and cortical changes were accelerated with age in Terc−/− and Wrn−/−Terc−/− mice compared with older WT mice. Histological quantification of osteoblasts in aged mice showed a similar number of osteoblasts in all genotypes; however, significant decreases in osteoid, mineralization surface, mineral apposition rate and bone formation rate in older Terc−/− and Wrn−/−Terc−/− bone suggest that osteoblast dysfunction is a prominent feature of precocious aging in these mice. Except in the Wrn−/− single mutant, osteoclast number did not increase in any genotype. Significant alterations in mechanical parameters (structure model index, degree of anistrophy and moment of inertia) of the Terc−/− and Wrn−/−Terc−/− femurs compared with WT mice were also observed. Young Wrn−/−Terc−/− mice had a statistically significant increase in bone-marrow fat content compared with young WT mice, which remained elevated in aged double mutants. Taken together, our results suggest that Terc−/− and Wrn−/−Terc−/− mutants recapitulate the human bone aging phenotype and are useful models for studying age-related osteoporosis.

Purpose: Hot flashes are a common and debilitating symptom among survivors of breast cancer. This study aimed at evaluating the effects of electroacupuncture (EA) versus gabapentin (GP) for hot flashes among survivors of breast cancer, with a specific focus on the placebo and nocebo effects., Patients and Methods: We conducted a randomized controlled trial involving 120 survivors of breast cancer experiencing bothersome hot flashes twice per day or greater. Participants were randomly assigned to receive 8 weeks of EA or GP once per day with validated placebo controls (sham acupuncture [SA] or placebo pills [PPs]). The primary end point was change in the hot flash composite score (HFCS) between SA and PP at week 8, with secondary end points including group comparisons and additional evaluation at week 24 for durability of treatment effects., Results: By week 8, SA produced significantly greater reduction in HFCS than did PP (-2.39; 95% CI, -4.60 to -0.17). Among all treatment groups, the mean reduction in HFCS was greatest in the EA group, followed by SA, GP, and PP (-7.4 v -5.9 v -5.2 v -3.4; P = < .001). The pill groups had more treatment-related adverse events than did the acupuncture groups: GP (39.3%), PP (20.0%), EA (16.7%), and SA (3.1%), with P = .005. By week 24, HFCS reduction was greatest in the EA group, followed by SA, PP, and GP (-8.5 v -6.1 v -4.6 v -2.8; P = .002)., Conclusion: Acupuncture produced larger placebo and smaller nocebo effects than did pills for the treatment of hot flashes. EA may be more effective than GP, with fewer adverse effects for managing hot flashes among breast cancer survivors; however, these preliminary findings need to be confirmed in larger randomized controlled trials with long-term follow-up., (© 2015 by American Society of Clinical Oncology.)