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Machine learning quantification of Amyloid-β deposits in the temporal lobe of 131 brain bank cases.
Accurate and scalable quantification of amyloid-β (Aβ) pathology is crucial for deeper disease phenotyping and furthering research in Alzheimer Disease (AD). This multidisciplinary study addresses the current limitations on neuropathology by leveraging a machine learning (ML) pipeline to perform a granular quantification of Aβ deposits and assess their distribution in the temporal lobe. Utilizing 131 whole-slide-images from consecutive autopsied cases at the University of California Davis Alzheimer Disease Research Center, our objectives were threefold: (1) Validate an automatic workflow for Aβ deposit quantification in white matter (WM) and gray matter (GM); (2) define the distributions of different Aβ deposit types in GM and WM, and (3) investigate correlates of Aβ deposits with dementia status and the presence of mixed pathology. Our methodology highlights the robustness and efficacy of the ML pipeline, demonstrating proficiency akin to experts' evaluations. We provide comprehensive insights into the quantification and distribution of Aβ deposits in the temporal GM and WM revealing a progressive increase in tandem with the severity of established diagnostic criteria (NIA-AA). We also present correlations of Aβ load with clinical diagnosis as well as presence/absence of mixed pathology. This study introduces a reproducible workflow, showcasing the practical use of ML approaches in the field of neuropathology, and use of the output data for correlative analyses. Acknowledging limitations, such as potential biases in the ML model and current ML classifications, we propose avenues for future research to refine and expand the methodology. We hope to contribute to the broader landscape of neuropathology advancements, ML applications, and precision medicine, paving the way for deep phenotyping of AD brain cases and establishing a foundation for further advancements in neuropathological research
Manejo de irrigação para cafeeiros propagador por embriogênese somática
A irrigação do cafeeiro tem se tornado prática cada vez mais frequente e necessária, uma vez que a cafeicultura tem migrado para regiões antes consideradas não aptas ao cultivo do café. Mesmo em regiões consideradas aptas quanto a deficiência hídrica como a região do sul de Minas, o uso da irrigação vem se tornando prática crescente. Porém, ainda são escassos os estudos sobre a adaptabilidade de cafeeiros provenientes de embriogênese somática a irrigação em condições de campo. Dessa maneira o objetivo desse trabalho foi determinar os níveis adequados de reposição de água de irrigação para cafeeiros oriundos de mudas propagadas por embriogênese somática. O experimento foi instalado no setor de cafeicultura da Universidade Federal de Lavras, onde foram plantadas mudas de Siriema, clone 03 resistente a ferrugem e ao bicho mineiro. O experimento foi instalado em blocos casualizados, com quatro repetições e seis tratamentos. Os tratamentos foram compostos de seis lâminas de irrigação baseadas em frações do Kc, constituídas de 0,4 (T2); 0,7 (T3); 1,0 (T4); 1,3 (T5); 1,6 (T6) e não irrigado (T1). Sendo aplicadas 75,22; 131,63; 188,05; 244,46 e 300,88 mm respectivamente aos tratamentos T2, T3, T4, T5 e T6. Foram avaliados durante o período de um ano após a implantação da lavoura a altura e o diâmetro de copa dos cafeeiros, sendo a parcela constituída por oito plantas e avaliada as seis plantas centrais. Os resultados mostraram que as parcelas irrigadas apresentaram aumento do Índice de área foliar (IAF) até uma lâmina máxima de 225,25 mm, correspondente a fração de 1,2 do Kc. Este crescimento correspondeu a 1,46 m².m-2 do IAF, cerca de 43,13% a mais que as parcelas não irrigadas
Obese mice exposed to psychosocial stress display cardiac and hippocampal dysfunction associated with local brain-derived neurotrophic factor depletion
Introduction: Obesity and psychosocial stress (PS) co-exist in individuals of Western society. Nevertheless, how PS impacts cardiac and hippocampal phenotype in obese subjects is still unknown. Nor is it clear whether changes in local brain-derived neurotrophic factor (BDNF) account, at least in part, for myocardial and behavioral abnormalities in obese experiencing PS. Methods: In adult male WT mice, obesity was induced via a high-fat diet (HFD). The resident-intruder paradigm was superimposed to trigger PS. In vivo left ventricular (LV) performance was evaluated by echocardiography and pressure-volume loops. Behaviour was indagated by elevated plus maze (EPM) and Y-maze. LV myocardium was assayed for apoptosis, fibrosis, vessel density and oxidative stress. Hippocampus was analyzed for volume, neurogenesis, GABAergic markers and astrogliosis. Cardiac and hippocampal BDNF and TrkB levels were measured by ELISA and WB. We investigated the pathogenetic role played by BDNF signaling in additional cardiac-selective TrkB (cTrkB) KO mice. Findings: When combined, obesity and PS jeopardized LV performance, causing prominent apoptosis, fibrosis, oxidative stress and remodeling of the larger coronary branches, along with lower BDNF and TrkB levels. HFD/PS weakened LV function similarly in WT and cTrkB KO mice. The latter exhibited elevated LV ROS emission already at baseline. Obesity/PS augmented anxiety-like behaviour and impaired spatial memory. These changes were coupled to reduced hippocampal volume, neurogenesis, local BDNF and TrkB content and augmented astrogliosis. Interpretation: PS and obesity synergistically deteriorate myocardial structure and function by depleting cardiac BDNF/TrkB content, leading to augmented oxidative stress. This comorbidity triggers behavioral deficits and induces hippocampal remodeling, potentially via lower BDNF and TrkB levels. Fund: J.A. was in part supported by Rotary Foundation Global Study Scholarship. G.K. was supported by T32 National Institute of Health (NIH) training grant under award number 1T32AG058527. S.C. was funded by American Heart Association Career Development Award (19CDA34760185). G.A.R.C. was funded by NIH (K01HL133368-01). APB was funded by a Grant from the Friuli Venezia Giulia Region entitled: “Heart failure as the Alzheimer disease of the heart; therapeutic and diagnostic opportunities”. M.C. was supported by PRONAT project (CNR). N.P. was funded by NIH (R01 HL136918) and by the Magic-That-Matters fund (JHU). V.L. was in part supported by institutional funds from Scuola Superiore Sant'Anna (Pisa, Italy), by the TIM-Telecom Italia (WHITE Lab, Pisa, Italy), by a research grant from Pastificio Attilio Mastromauro Granoro s.r.l. (Corato, Italy) and in part by ETHERNA project (Prog. n. 161/16, Fondazione Pisa, Italy). Funding source had no such involvement in study design, in the collection, analysis, interpretation of data, in the writing of the report; and in the decision to submit the paper for publication
Results of an open label feasibility study of sodium valproate in people with McArdle disease
McArdle disease results from a lack of muscle glycogen phosphorylase in skeletal muscle tissue. Regenerating skeletal muscle fibres can express the brain glycogen phosphorylase isoenzyme. Stimulating expression of this enzyme could be a therapeutic strategy. Animal model studies indicate that sodium valproate (VPA) can increase expression of phosphorylase in skeletal muscle affected with McArdle disease. This study was designed to assess whether VPA can modify expression of brain phosphorylase isoenzyme in people with McArdle disease. This phase II, open label, feasibility pilot study to assess efficacy of six months treatment with VPA (20 mg/kg/day) included 16 people with McArdle disease. Primary outcome assessed changes in VO2peak during an incremental cycle test. Secondary outcomes included: phosphorylase enzyme expression in post-treatment muscle biopsy, total distance walked in 12 min, plasma lactate change (forearm exercise test) and quality of life (SF36). Safety parameters. 14 participants completed the trial, VPA treatment was well tolerated; weight gain was the most frequently reported drug-related adverse event. There was no clinically meaningful change in any of the primary or secondary outcome measures including: VO2peak, 12 min walk test and muscle biopsy to look for a change in the number of phosphorylase positive fibres between baseline and 6 months of treatment. Although this was a small open label feasibility study, it suggests that a larger randomised controlled study of VPA, may not be worthwhile
Astro-photometric study of M37 with Gaia and wide-field ugi-imaging
We present an astrometric and photometric wide-field study of the Galactic
open star cluster M37 (NGC 2099). The studied field was observed with
ground-based images covering a region of about four square degrees in the
Sloan-like filters ugi. We exploited the Gaia catalogue to calibrate the
geometric distortion of the large field mosaics, developing software routines
that can be also applied to other wide-field instruments. The data are used to
identify the hottest white dwarf (WD) member candidates of M37. Thanks to the
Gaia EDR3 exquisite astrometry we identified seven such WD candidates, one of
which, besides being a high-probability astrometric member, is the putative
central star of a planetary nebula. To our knowledge, this is a unique object
in an open cluster, and we have obtained follow-up low-resolution spectra that
are used for a qualitative characterisation of this young WD. Finally, we
publicly release a three-colour atlas and a catalogue of the sources in the
field of view, which represents a complement of existing material.Comment: 13 pages, 4 table, 13 figures. Accepted for publication in MNRAS on
2022, July 6, manuscript ID. MN-22-2264-M
Risdiplam in Type 1 Spinal Muscular Atrophy
BACKGROUND: Type 1 spinal muscular atrophy is a rare, progressive neuromuscular disease that is caused by low levels of functional survival of motor neuron (SMN) protein. Risdiplam is an orally administered, small molecule that modifies SMN2 pre-messenger RNA splicing and increases levels of functional SMN protein. METHODS: We report the results of part 1 of a two-part, phase 2-3, open-label study of risdiplam in infants 1 to 7 months of age who had type 1 spinal muscular atrophy, which is characterized by the infant not attaining the ability to sit without support. Primary outcomes were safety, pharmacokinetics, pharmacodynamics (including the blood SMN protein concentration), and the selection of the risdiplam dose for part 2 of the study. Exploratory outcomes included the ability to sit without support for at least 5 seconds. RESULTS: A total of 21 infants were enrolled. Four infants were in a low-dose cohort and were treated with a final dose at month 12 of 0.08 mg of risdiplam per kilogram of body weight per day, and 17 were in a high-dose cohort and were treated with a final dose at month 12 of 0.2 mg per kilogram per day. The baseline median SMN protein concentrations in blood were 1.31 ng per milliliter in the low-dose cohort and 2.54 ng per milliliter in the high-dose cohort; at 12 months, the median values increased to 3.05 ng per milliliter and 5.66 ng per milliliter, respectively, which represented a median of 3.0 times and 1.9 times the baseline values in the low-dose and high-dose cohorts, respectively. Serious adverse events included pneumonia, respiratory tract infection, and acute respiratory failure. At the time of this publication, 4 infants had died of respiratory complications. Seven infants in the high-dose cohort and no infants in the low-dose cohort were able to sit without support for at least 5 seconds. The higher dose of risdiplam (0.2 mg per kilogram per day) was selected for part 2 of the study. CONCLUSIONS: In infants with type 1 spinal muscular atrophy, treatment with oral risdiplam led to an increased expression of functional SMN protein in the blood. (Funded by F. Hoffmann-La Roche; ClinicalTrials.gov number, NCT02913482.)
Creation and implementation of a European registry for patients with McArdle disease and other muscle glycogenoses (EUROMAC registry)
BACKGROUND: International patient registries are of particular importance for rare disorders, as they may contribute to overcome the lack of knowledge derived from low number of patients and limited awareness of these diseases, and help to learn more about their geographical or population-based specificities, which is relevant for research purposes and for promoting better standards of care and diagnosis. Our objective was to create and implement a European registry for patients with McArdle disease and other muscle glycogenoses (EUROMAC) and to disseminate the knowledge of these disorders. RESULTS: Teams from nine different countries (United Kingdom, Spain, Italy, France, Germany, Denmark, Greece, Turkey and USA) created a consortium that developed the first European registry dedicated to rare muscle glycogenoses. A work plan was implemented to design the database and platform that constitute the registry, by choosing clinical, genetics and molecular variables of interest, based on experience gained from previous national registries for similar metabolic disorders. Among dissemination activities, several teaching events were organized in different countries, especially those where the consortium considered the awareness of these diseases needs to be promoted among health professionals and patients. CONCLUSION: EUROMAC represents a step forward in the knowledge of those disorders to which it is dedicated, and will have relevant clinical outcomes at the diagnostic, epidemiological, clinical and research level
Rohlin Distance and the Evolution of Influenza A virus: Weak Attractors and Precursors
The evolution of the hemagglutinin amino acids sequences of Influenza A virus
is studied by a method based on an informational metrics, originally introduced
by Rohlin for partitions in abstract probability spaces. This metrics does not
require any previous functional or syntactic knowledge about the sequences and
it is sensitive to the correlated variations in the characters disposition. Its
efficiency is improved by algorithmic tools, designed to enhance the detection
of the novelty and to reduce the noise of useless mutations. We focus on the
USA data from 1993/94 to 2010/2011 for A/H3N2 and on USA data from 2006/07 to
2010/2011 for A/H1N1 . We show that the clusterization of the distance matrix
gives strong evidence to a structure of domains in the sequence space, acting
as weak attractors for the evolution, in very good agreement with the
epidemiological history of the virus. The structure proves very robust with
respect to the variations of the clusterization parameters, and extremely
coherent when restricting the observation window. The results suggest an
efficient strategy in the vaccine forecast, based on the presence of
"precursors" (or "buds") populating the most recent attractor.Comment: 13 pages, 5+4 figure
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