Use of fuzzy edge single-photon emission computed tomography analysis in definite Alzheimer's disease - a retrospective study

<p>Abstract</p> <p>Background</p> <p>Definite Alzheimer's disease (AD) requires neuropathological confirmation. Single-photon emission computed tomography (SPECT) may enhance diagnostic accuracy, but due to restricted sensitivity and specificity, the role of SPECT is largely limited with regard to this purpose.</p> <p>Methods</p> <p>We propose a new method of SPECT data analysis. The method is based on a combination of parietal lobe selection (as regions-of-interest (ROI)), 3D fuzzy edge detection, and 3D watershed transformation. We applied the algorithm to three-dimensional SPECT images of human brains and compared the number of watershed regions inside the ROI between AD patients and controls. The Student's two-sample t-test was used for testing domain number equity in both groups.</p> <p>Results</p> <p>AD patients had a significantly reduced number of watershed regions compared to controls (<it>p </it>< 0.01). A sensitivity of 94.1% and specificity of 80% was obtained with a threshold value of 57.11 for the watershed domain number. The narrowing of the SPECT analysis to parietal regions leads to a substantial increase in both sensitivity and specificity.</p> <p>Conclusions</p> <p>Our non-invasive, relatively low-cost, and easy method can contribute to a more precise diagnosis of AD.</p

Waveguide-integrated colloidal nanocrystal supraparticle lasers

Supraparticle (SP) microlasers fabricated by the self-assembly of colloidal nanocrystals have great potential as coherent optical sources for integrated photonics. However, their deterministic placement for integration with other photonic elements remains an unsolved challenge. In this work, we demonstrate the manipulation and printing of individual SP microlasers, laying the foundation for their use in more complex photonic integrated circuits. We fabricate CdSxSe1−x/ZnS colloidal quantum dot (CQD) SPs with diameters from 4 to 20 μm and Q-factors of approximately 300 via an oil-in-water self-assembly process. Under a subnanosecond-pulse optical excitation at 532 nm, the laser threshold is reached at an average number of excitons per CQD of 2.6, with modes oscillating between 625 and 655 nm. Microtransfer printing is used to pick up individual CQD SPs from an initial substrate and move them to a different one without affecting their capability for lasing. As a proof of concept, a CQD SP is printed on the side of an SU-8 waveguide, and its modes are successfully coupled to the waveguide

Clinical and molecular practice of European thoracic pathology laboratories during the COVID-19 pandemic. The past and the near future

BACKGROUND: This study evaluated the consequences in Europe of the COVID-19 outbreak on pathology laboratories orientated toward the diagnosis of thoracic diseases. MATERIALS AND METHODS: A survey was sent to 71 pathology laboratories from 21 European countries. The questionnaire requested information concerning the organization of biosafety, the clinical and molecular pathology, the biobanking, the workload, the associated research into COVID-19, and the organization of education and training during the COVID-19 crisis, from 15 March to 31 May 2020, compared with the same period in 2019. RESULTS: Questionnaires were returned from 53/71 (75%) laboratories from 18 European countries. The biosafety procedures were heterogeneous. The workload in clinical and molecular pathology decreased dramatically by 31% (range, 3%-55%) and 26% (range, 7%-62%), respectively. According to the professional category, between 28% and 41% of the staff members were not present in the laboratories but did teleworking. A total of 70% of the laboratories developed virtual meetings for the training of residents and junior pathologists. During the period of study, none of the staff members with confirmed COVID-19 became infected as a result of handling samples. CONCLUSIONS: The COVID-19 pandemic has had a strong impact on most of the European pathology laboratories included in this study. Urgent implementation of several changes to the organization of most of these laboratories, notably to better harmonize biosafety procedures, was noted at the onset of the pandemic and maintained in the event of a new wave of infection occurring in Europe

Clinical and molecular practice of European thoracic pathology laboratories during the COVID-19 pandemic. The past and the near future.

This study evaluated the consequences in Europe of the COVID-19 outbreak on pathology laboratories orientated toward the diagnosis of thoracic diseases. A survey was sent to 71 pathology laboratories from 21 European countries. The questionnaire requested information concerning the organization of biosafety, the clinical and molecular pathology, the biobanking, the workload, the associated research into COVID-19, and the organization of education and training during the COVID-19 crisis, from 15 March to 31 May 2020, compared with the same period in 2019. Questionnaires were returned from 53/71 (75%) laboratories from 18 European countries. The biosafety procedures were heterogeneous. The workload in clinical and molecular pathology decreased dramatically by 31% (range, 3%-55%) and 26% (range, 7%-62%), respectively. According to the professional category, between 28% and 41% of the staff members were not present in the laboratories but did teleworking. A total of 70% of the laboratories developed virtual meetings for the training of residents and junior pathologists. During the period of study, none of the staff members with confirmed COVID-19 became infected as a result of handling samples. The COVID-19 pandemic has had a strong impact on most of the European pathology laboratories included in this study. Urgent implementation of several changes to the organization of most of these laboratories, notably to better harmonize biosafety procedures, was noted at the onset of the pandemic and maintained in the event of a new wave of infection occurring in Europe

Deleterious ABCA7 mutations and transcript rescue mechanisms in early onset Alzheimer’s disease

Abstract: Premature termination codon (PTC) mutations in the ATP-Binding Cassette, Sub-Family A, Member 7 gene (ABCA7) have recently been identified as intermediate-to-high penetrant risk factor for late-onset Alzheimer's disease (LOAD). High variability, however, is observed in downstream ABCA7 mRNA and protein expression, disease penetrance, and onset age, indicative of unknown modifying factors. Here, we investigated the prevalence and disease penetrance of ABCA7 PTC mutations in a large early onset AD (EOAD)-control cohort, and examined the effect on transcript level with comprehensive third-generation long-read sequencing. We characterized the ABCA7 coding sequence with next-generation sequencing in 928 EOAD patients and 980 matched control individuals. With MetaSKAT rare variant association analysis, we observed a fivefold enrichment (p = 0.0004) of PTC mutations in EOAD patients (3%) versus controls (0.6%). Ten novel PTC mutations were only observed in patients, and PTC mutation carriers in general had an increased familial AD load. In addition, we observed nominal risk reducing trends for three common coding variants. Seven PTC mutations were further analyzed using targeted long-read cDNA sequencing on an Oxford Nanopore MinION platform. PTC-containing transcripts for each investigated PTC mutation were observed at varying proportion (5-41% of the total read count), implying incomplete nonsense-mediated mRNA decay (NMD). Furthermore, we distinguished and phased several previously unknown alternative splicing events (up to 30% of transcripts). In conjunction with PTC mutations, several of these novel ABCA7 isoforms have the potential to rescue deleterious PTC effects. In conclusion, ABCA7 PTC mutations play a substantial role in EOAD, warranting genetic screening of ABCA7 in genetically unexplained patients. Long-read cDNA sequencing revealed both varying degrees of NMD and transcript-modifying events, which may influence ABCA7 dosage, disease severity, and may create opportunities for therapeutic interventions in AD

Global maps of soil temperature

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world\u27s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

Clinical and molecular practice of European thoracic pathology laboratories during the COVID-19 pandemic The past and the near future

BackgroundThis study evaluated the consequences in Europe of the COVID-19 outbreak on pathology laboratories orientated toward the diagnosis of thoracic diseases.Materials and methodsA survey was sent to 71 pathology laboratories from 21 European countries. The questionnaire requested information concerning the organization of biosafety, the clinical and molecular pathology, the biobanking, the workload, the associated research into COVID-19, and the organization of education and training during the COVID-19 crisis, from 15 March to 31 May 2020, compared with the same period in 2019.ResultsQuestionnaires were returned from 53/71 (75%) laboratories from 18 European countries. The biosafety procedures were heterogeneous. The workload in clinical and molecular pathology decreased dramatically by 31% (range, 3%-55%) and 26% (range, 7%-62%), respectively. According to the professional category, between 28% and 41% of the staff members were not present in the laboratories but did teleworking. A total of 70% of the laboratories developed virtual meetings for the training of residents and junior pathologists. During the period of study, none of the staff members with confirmed COVID-19 became infected as a result of handling samples.ConclusionsThe COVID-19 pandemic has had a strong impact on most of the European pathology laboratories included in this study. Urgent implementation of several changes to the organization of most of these laboratories, notably to better harmonize biosafety procedures, was noted at the onset of the pandemic and maintained in the event of a new wave of infection occurring in Europe

New insights in the dia gnosis and treatment of amyotrophic lateral sclerosis

Amyotrofi cká laterální skleróza (ALS) patří mezi progredující neurodegeneativní onemocnění, jehož prevalence s věkem stoupá. Dochází k pozvolnému zániku periferních a centrálních motoneuronů a jejich drah s ušetřením extraokulárních a sfinkterových svalů. Rozlišuje se klasická forma ALS s postižením centrálního a periferního motoneuronu, a dále progresivní bulbární paralýza s postižením bulbárních svalů. Vzácnější jsou progresivní svalová atrofie s lézí pouze periferního motoneuronu a primární laterální skleróza s postižením pouze centrálního motoneuronu. Existují formy ALS sdružené s demencí (frontotemporální lobární demence [frontotemporal lobar dementia-motor neuron dis ease; FTLD-MND]), u kterých jsou přítomny poruchy chování, kognitivní dysfunkce a postižení exekutivních funkcí. Příčina nemoci zatím není objasněna. Jde o řetězec následných dějů, na jehož konci je programově řízená smrt buňky v selektivních subpopulacích neuronů. V práci je detailně popsán neuropatologický nález vč. podrobného molekulárně genetického rozboru u familiárních forem ALS. V současné době neexistuje specifi cký lék na toto onemocnění. Používá se neuroprotektivní léčba (např. riluzol a nově edaravon) s nejednoznačným efektem a léčba symp tomatická, která je určena k zvládání doprovodných projevů. Jednotlivé léčebné možnosti jsou podrobně rozebrány.Amyotrophic lateral sclerosis (ALS) is a progres sive neurodegenerative dis ease of increased prevalence with age. The main fi ndings are loss of peripheral and central motoneurons and their pathways with extraocular and sphincter muscle sparing. These are clas sical forms of ALS with loss of central and peripheral motoneurons, as well as progres sive bulbar paralysis with impairment of bulbar muscles. Progres sive muscle atrophy with only peripheral motoneuron lesions and primary lateral sclerosis with only central motoneuron involvement are rarely found. There are some forms of ALS as sociated with dementia (frontotemporal lobar dementia-motor neuron dis ease [FTLDMND]) with behavioral changes, cognitive and executive dysfunction. The cause of ALS has not yet been elucidated. It is a chain of fol low-up events, at the end of which is cell death in selective subpopulations of neurons. In the present paper, we describe in detail the neuropathological fi ndings and molecular genetic analysis in familial forms of ALS. A specifi c drug for this dis ease is still unknown. Neuroprotective drugs (such as riluzole and recently edaravon) have an ambiguous eff ect. Symp tomatic treatment is designed to manage concomitant manifestations. Different treatment options are discus sed in detail

Experimental all-optical relay-assisted FSO link with regeneration and forward scheme for ultra-short pulse transmission

This paper presents experimental results for an all-optical free-space optical (FSO) relay-assisted system by employing an all-optical regenerate and forward (AORF) scheme in order to increase the transmission link span. The ultra-short pulse (i.e., 2 ps) regeneration technique based on Mamyshev method is adopted. We have developed a dedicated experimental test-bed composed of optical fiber components and FSO links to demonstrate the proposed scheme and evaluate its performance in terms of the Q-factor and bit error rate (BER) under turbulence regimes for both single and dual-hop network architectures. We show that, using the AORF a hundred times improvement in the BER performance is achieved compared to the amplify-and-forward scheme for a fixed signal-to-noise ratio under turbulence conditions