bluuebunny/crossref_metadata_2025_split huggingface dataset:
In Vivo Cortical Microstructure: A Proxy for Tauopathy and Cognitive impairment in the Elderly with and without MCI/Dementia
Authors: Anderson John A. E. , Schifani Christin , Nazeri Arash , Voineskos Aristotle N. ,   for the Alzheimer’s Disease Neuroimaging Initiative
Published: March 2021

AbstractAggregation of hyperphosphorylated tau protein is currently one of the most reliable indicators of Alzheimer’s pathology and cognitive impairment in older adults. However, it would be useful to have a non-invasive, accessible proxy measure that does not rely on Positron Emission Tomography (PET). We used data from multi-shell diffusion-weighted imaging (DWI) to assess indices from the Neurite Orientation Dispersion and Density Imaging (NODDI) model to determine possible proxies for tau and relationship with cognitive impairment. After controlling for age, sex, and the time difference between the scan acquisitions (DWI vs. PET), we used multiple factor analysis (MFA) to assess the fit between NODDI indices (orientation dispersion [ODI], neurite density [NDI], and free-water [fISO]), cortical thickness, and tau binding (via PET). We used data from 80 participants from the ADNI-3 sample who had a multi-shell DWI and an [18F]AV-1451 (tau) PET scan. Of these 80, 49 individuals were considered cognitively normal older adults (age ~74 years), 26 individuals had a diagnosis of mild cognitive impairment (age ~75 years), and five individuals had Alzheimer’s dementia (age ~78 years). fISO and tau shared a large amount of spatial overlap, and both strongly correlated with the first MFA dimension. Macrostructural features (such as cortical thickness and subcortical volume) introduced in a follow-up analysis were less related to this first MFA dimension than fISO and eight percent less than tau. Subsequent mediation analyses demonstrated that fISO mediated the relationship between cortical thickness and tau, explaining all of the variance. Microstructural features derived from advanced DWI acquisitions such as fISO may be useful proxies for tau. Cortical fISO, rather than cortical thickness, may represent the impact of tau on the brain (and, by extension, cognition).
Comparativein vitroantioxidant and antibacterial activities of leaf extract fractions of Crimson bottlebrush,Callistemon citrinus(Curtis.) Skeels
Authors: Ghosh Poulomi , Goswami Souren , Roy Sujit , Das Ria , Chakraborty Tista , Ray Sanjib 
Published: March 2021

AbstractObjectivesThe present study aimed to analyze a comparativein vitrofree radical scavenging and antibacterial potentials of leaf aqueous and the successive extract fractions ofCallistemon citrinus.MethodsForin vitroantioxidant activity assessments, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, Fe3+ion reducing antioxidant power (FRAP) assay, and total antioxidant capacity of the extracts were tested. Antibacterial potentials were tested through Agar well diffusion method using both gram-positive and gram-negative bacterial strains.ResultsData indicate the polar successive aqueous fraction (AQF) possesses the highest free radicals scavenging capacity, with lowest EC50(the required extract concentration to scavenge half of the free radicals) for DPPH and FRAP assays, and contains the highest total phenolics (308.2±5.9 µg tannic acid equivalent/mg dry extract, DE), flavonoids (516.7±3.5 µg quercetin equivalent/mg DE), total antioxidant capacity (441.48±12.8 µg ascorbic acid equivalent/mg DE). Phenolics and flavonoids contents were positively correlated with thein vitroantioxidant activities. The antibacterial study indicates the petroleum ether and chloroform are suitable solvents for extracting antibacterial phytochemicals fromC. citrinusleaves that are effective against both gram-positive and negative bacterial strains.ConclusionThe most polar fractioni.e. the successive aqueous extract fraction ofC. citrinusleaves exhibited the highest antioxidant activities while the most non-polar petroleum ether extract fraction showed the highest antibacterial potentials thus these extract fractions might have therapeutic importance.
A spatial and cellular distribution of neurotropic virus infection in the mouse brain revealed by fMOST and single cell RNA-seq
Authors: Zhang Yachun , Xing Xudong , Long Ben , Cao Yandi , Hu Simeng , Li Xiangning , Yu Yalan , Tian Dayong , Sui Baokun , Luo Zhaochen , Liu Wei , Lv Lei , Wu Qiong , Dai Jinxia , Zhou Ming , Han Heyou , Fu Zhen F. , Gong Hui , Bai Fan , Zhao Ling 
Published: March 2021

SummaryNeurotropic virus infection can cause serious damage to the central nervous system (CNS) in both human and animals. The complexity of the CNS poses unique challenges to investigate the infection of these viruses in the brain using traditional techniques. In this study, we explore the use of fluorescence micro-optical sectioning tomography (fMOST) and single cell RNA sequencing (scRNA-seq) to map the spatial and cellular distribution of a representative neurotropic virus, rabies virus (RABV), in the whole brain. Mice were inoculated with a lethal dose of recombinant RABV expressing enhanced green fluorescent protein (EGFP) under different infection routes, and a three-dimensional view of the distribution of RABV in the whole mouse brain was obtained using fMOST. Meanwhile, we pinpointed the cellular distribution of RABV by utilizing scRNA-seq. Our fMOST data provide the first evidence that RABV can infect multiple nuclei related to fear independent of different infection routes. More surprisingly, scRNA-seq data indicate that besides neurons RABV can infect macrophages and NK cellsin vivo. Collectively, this study draws a comprehensively spatial and cellular map of RABV infection in the mouse brain, providing a novel and insightful strategy to investigate the pathogenesis of neurotropic viruses.
Histologic and Proteomic Remodeling of the Pulmonary Veins and Arteries in a Porcine Model of Chronic Pulmonary Venous Hypertension
Authors: Fayyaz Ahmed U. , Sabbah Michael S. , Dasari Surendra , Griffiths Leigh G. , DuBrock Hilary M. , Charlesworth M. Cristine , Borlaug Barry A. , Jenkins Sarah M. , Edwards William D. , Redfield Margaret M. 
Published: March 2021

ABSTRACTAIMIn heart failure (HF), pulmonary venous hypertension (PVH) produces pulmonary hypertension (PH) with remodeling of pulmonary veins (PV) and arteries (PA). In a porcine PVH model, we performed proteomic-based bioinformatics to investigate unique pathophysiologic mechanisms mediating PA and PV remodeling.METHODSLarge PV were banded (PVH, n= 10) or not (Sham, n=9) in piglets. At sacrifice, PV and PA were perfusion labeled for vessel specific histology and proteomics. The PA and PV were separately sampled with laser-capture micro-dissection for mass spectrometry.RESULTSPulmonary vascular resistance (Wood Units; 8.6 versus 2.0) and PA (19.9 versus 10.3) and PV (14.2 versus 7.6) wall thickness/external diameter (%) were increased in PVH (p<0.01 for all). Similar numbers of proteins were identified in PA (2093) and PV (2085) with 94% overlap, but biological processes differed. There were more differentially expressed proteins (287 versus 161), altered canonical pathways (17 versus 3) and predicted up-stream regulators (PUSR; 22 versus 6) in PV than PA. In PA and PV, bioinformatics indicated activation of the integrated stress response and mTOR signaling with dysregulated growth. In PV, there was also activation of Rho/Rho kinase signaling with decreased actin cytoskeletal signaling and altered tight and adherens junctions, ephrin B, and caveolar mediated endocytosis signaling; all indicating disrupted endothelial barrier function. Indeed, protein biomarkers and the top PUSR in PV (TGF-β) indicated endothelial mesenchymal transition (EndoMT) in PV. Findings were confirmed in human autopsy specimens.CONCLUSIONThese findings provide new therapeutic targets to oppose pulmonary vascular remodeling in HF-related PH.TRANSLATIONAL PERSPECTIVEIn heart failure (HF) related (Group 2) PH, despite remodeling of pulmonary veins (PV) and arteries (PA), therapies targeting PA biology altered in Group 1 PH have not shown consistent benefit. In a porcine Group 2 PH model, microdissection allowed vessel specific (PV and PA) proteomics/bioinformatics. In PA and PV, the integrated stress response and mTOR signaling were activated with evidence of dysregulated growth. In PV, many more pathways were altered with broad evidence of disrupted endothelial barrier function and endothelial mesenchymal transition. Findings were confirmed in human specimens and provide new therapeutic targets in Group 2 PH.
Lumican regulates cervical corticospinal axon collateralization via non-autonomous crosstalk between distinct corticospinal neuron subpopulations
Authors: Itoh Yasuhiro , Sahni Vibhu , Shnider Sara J. , Macklis Jeffrey D. 
Published: March 2021

AbstractCorticospinal neurons (CSN) are the cortical projection neurons that innervate the spinal cord and some brainstem targets with segmental precision to control voluntary movement of specific functional motor groups, limb sections, or individual digits. CSN subpopulations exhibit striking axon targeting specificity from development into maturity: Evolutionarily newer rostrolateral CSN exclusively innervatebulbar-cervical targets (CSNBC-lat), while evolutionarily older caudomedial CSN (CSNmedial) are more heterogeneous, with distinct subpopulations extending axons to either bulbar-cervical or thoraco-lumbar segments. However, molecular regulation over specificity of CSN segmental target innervation is essentially unknown. The cervical cord, with its evolutionarily enhanced precision of forelimb movement, is innervated by multiple CSN subpopulations, suggesting inter-neuronal interactions in establishing cervical corticospinal circuitry. Here, we identify that Lumican, previously unrecognized in axon development, controls the balance of innervation between CSNBC-latand CSNmedialwithin the cervical spinal cord. Remarkably, Lumican, an extracellular matrix protein expressed by CSNBC-lat, non-cell-autonomously suppresses axon collateralization in the cervical cord by CSNmedial. Intersectional viral labeling and mouse genetics further identify that Lumican controls axon collateralization by multiple CSN subpopulations in caudomedial sensorimotor cortex. These results identify inter-axonal molecular crosstalk between CSN subpopulations as a novel mechanism controlling corticospinal circuitry, target density, and competitive specificity. Further, this mechanism has potential implications for evolutionary diversification of corticospinal circuitry with finer scale precision.
Occurrence of COVID-19 symptoms during SARS-CoV-2 infection defines waning of humoral immunity
Authors: Wu Jun , Liang Bo-Yun , Fang Yao-Hui , Wang Hua , Yang Xiao-Li , Shen Shu , Chen Liang-Kai , Li Su-Meng , Lu Si-Hong , Xiang Tian-Dan , Liu Jia , Le-Trilling Vu Thuy Khanh , Lu Meng-Ji , Yang Dong-Liang , Deng Fei , Dittmer Ulf , Trilling Mirko , Zheng Xin 
Published: March 2021

AbstractApproximately half of the SARS-CoV-2 infections occur without apparent symptoms, raising questions regarding long-term humoral immunity in asymptomatic individuals. Plasma levels of immunoglobulin G (IgG) and M (IgM) against the viral spike or nucleoprotein were determined for 25,091 individuals enrolled in a surveillance program in Wuhan, China. We compared 405 asymptomatic individuals with 459 symptomatic COVID-19 patients. The well-defined duration of the SARS-CoV-2 endemic in Wuhan allowed a side-by-side comparison of antibody responses following symptomatic and asymptomatic infections without subsequent antigen re-exposure. IgM responses rapidly declined in both groups. However, both the prevalence and durability of IgG responses and neutralizing capacities correlated positively with symptoms. Regardless of sex, age, and body weight, asymptomatic individuals lost their SARS-CoV-2-specific IgG antibodies more often and rapidly than symptomatic patients. These findings have important implications for immunity and favour immunization programs including individuals after asymptomatic infections.One-Sentence SummaryPrevalence and durability of SARS-CoV-2-specific IgG responses and neutralizing capacities correlate with COVID-19 symptoms.
A projectome of the bumblebee central complex
Authors: Sayre Marcel E. , Templin Rachel , Chavez Johanna , Kempenaers Julian , Heinze Stanley 
Published: March 2021

AbstractInsects have evolved diverse and remarkable strategies for navigating in various ecologies all over the world. Regardless of species, insects share the presence of a group of morphologically conserved neuropils known collectively as the central complex (CX). The CX is a navigational hub, involved in sensory integration and coordinated motor activity. Despite the fact that our understanding of navigational behavior comes predominantly from ants and bees, most of what we know about the underlying neural circuitry of such behavior comes from work in fruit flies. Here we aim to close this gap, by providing the first comprehensive map of all major columnar neurons and their projection patterns in the CX of a bee. We find numerous components of the circuit that appear to be highly conserved between the fly and the bee, but also highlight several key differences which are likely to have important functional ramifications.
Comparative multi-tissue profiling reveals extensive tissue-specificity in transcriptome reprogramming upon cold exposure
Authors: Hadadi Noushin , Spiljar Martina , Steinbach Karin , Salinas Gabriela , Merkler Doron , Trajkovski Mirko 
Published: March 2021

ABSTRACTCold exposure is an extensively used intervention for enhancing thermogenic and mitochondrial activity in adipose tissues. As such, it has been suggested as a potential lifestyle intervention for body weight maintenance. The metabolic consequences of cold acclimation are not limited to the adipose tissues, however the impact on rest of the tissues in context of their gene expression profile remains unclear. Here we provide a systematic characterization of cold exposure-mediated effects in a comparative multi-tissue RNA sequencing approach using wide range of organs including spleen, bone marrow, spinal cord, brain, hypothalamus, ileum, liver, subcutaneous-, visceral- and brown adipose tissues. Our findings highlight that transcriptional responses to cold exposure exhibit high degree of tissue-specificity both at the gene level and at GO enrichment gene sets, which is not directed by the basal gene expression pattern exhibited by the various organs. Our study places the cold adaptation of individual tissues in a whole-organism framework and provides an integrative transcriptional analysis necessary for understanding the cold exposure-mediated biological reprograming.
The temperature-regulated DEAD-box RNA helicase CrhR interactome: Autoregulation and photosynthesis-related transcripts
Authors: Migur Anzhela , Heyl Florian , Fuss Janina , Srikumar Afshan , Huettel Bruno , Steglich Claudia , Prakash Jogadhenu S. S. , Reinhardt Richard , Backofen Rolf , Owttrim George W. , Hess Wolfgang R. 
Published: March 2021

AbstractRNA helicases play crucial functions in RNA biology. In plants, RNA helicases are encoded by large gene families, performing roles in abiotic stress responses, development, the post-transcriptional regulation of gene expression as well as house-keeping functions. Several of these RNA helicases are targeted to the organelles, mitochondria and chloroplasts. Cyanobacteria are the direct evolutionary ancestors of plant chloroplasts. The cyanobacterium Synechocystis 6803 encodes a single DEAD-box RNA helicase, CrhR, that is induced by a range of abiotic stresses, including low temperature. Though the ΔcrhR mutant exhibits a severe cold-sensitive phenotype, the physiological function(s) performed by CrhR have not been described. To identify transcripts interacting with CrhR, we performed RNA co-immunoprecipitation with extracts from a Synechocystis crhR deletion mutant expressing the FLAG-tagged native CrhR or a K57A mutated version with an anticipated enhanced RNA binding. The composition of the interactome was strikingly biased towards photosynthesis-associated and redox-controlled transcripts. A transcript highly enriched in all experiments was the crhR mRNA, suggesting an auto-regulatory molecular mechanism. The identified interactome explains the described physiological role of CrhR in response to the redox poise of the photosynthetic electron transport chain and characterizes CrhR as an enzyme with a diverse range of transcripts as molecular targets.HighlightThe cyanobacterial DEAD-box RNA helicase CrhR binds mainly photosynthesis-associated and redox-controlled transcripts connecting its regulation, localization and phenotypes of mutants for the first time with a set of potential RNA targets.
Uvariopsis ebo(Annonaceae) a new, Critically Endangered tree species from the Ebo Forest, Cameroon and a key to the Cameroonian species ofUvariopsis
Authors: Gosline George , Cheek Martin , Onana Jean Michel , Ngansop Eric , van der Burgt Xander , Dagallier Leo-Paul 
Published: March 2021

SummaryA new species to science of evergreen forest tree,Uvariopsis ebo(Annonaceae) is described, illustrated, mapped, and compared morphologically with the other cauliflorous species of the genus. Restricted so far to a single site in evergreen lowland forest in the Ebo Forest, Yabassi, Littoral Region, Cameroon, this species is Critically Endangered using the IUCN 2012 standard, because the forest habitat of this species remains unprotected, and there exists threats of logging and conversion to plantations. This species adds to the growing list of threatened species resulting from anthropogenic pressure on Cameroon forests. Observations on the unusual corolla structure of the new species are made. A revised key to the 14 Cameroonian species ofUvariopsisis presented. Notes are given on other narrowly endemic and threatened species in the Ebo forest area, a highly threatened centre of diversity in Littoral Region, globally important for conservation.
A distinct brain expression profile for genes within large introgression deserts and under positive selection inHomo sapiens
Authors: Buisan Raül , Moriano Juan , Andirkó Alejandro , Boeckx Cedric 
Published: March 2021

AbstractAnalyses of ancient DNA from extinct hominins have provided unique insights into the complex evolutionary history ofHomo sapiens, intricately related to that of the Neanderthals and the Denisovans as revealed by several instances of admixture events. These analyses have also allowed the identification of introgression deserts: genomic regions in our species that are depleted of ‘archaic’ haplotypes. The presence of genes likeFOXP2in these deserts has been taken to be suggestive of brain-related functional differences betweenHomospecies. Here, we seek a deeper characterization of these regions, taking into account signals of positive selection in our lineage. Analyzing publicly available transcriptomic data from the human brain at different developmental stages, we found that structures outside the cerebral neocortex, in particular the cerebellum, the striatum and the mediodorsal nucleus of the thalamus show the most divergent transcriptomic profiles when considering genes within large introgression deserts and under positive selection.
Continuity within somatosensory cortical map shapes the integration of optogenetic input
Authors: Lassagne H. , Goueytes D. , Shulz D.E , Estebanez L. , Ego-Stengel V. 
Published: March 2021

AbstractThe topographic organization of sensory cortices is a prominent feature, but its functional role remains unclear. Particularly, how activity is integrated within a cortical area depending on its topography is unknown. Here, we trained mice expressing channelrhodopsin in cortical excitatory neurons to track a bar photostimulation that rotated smoothly over the primary somatosensory cortex (S1). When photostimulation was aimed at vS1, the area which contains a contiguous representation of the whisker array at the periphery, mice could learn to discriminate angular positions of the bar to obtain a reward. In contrast, they could not learn the task when the photostimulation was aimed at the representation of the trunk and legs in S1, where neighboring zones represent distant peripheral body parts, introducing discontinuities. Mice demonstrated anticipation of reward availability, specifically when cortical topography enabled to predict future sensory activation. These results are particularly helpful for designing efficient cortical sensory neuroprostheses.TeaserOptogenetic stimulation sweeping the cortical surface: A way to provide precise sensory information and guide behaviour.
Revisiting Decompression Sickness Risk and Mobility in the Context of the SmartSuit, a Hybrid Planetary Spacesuit
Authors: Kluis Logan , Diaz-Artiles Ana 
Published: March 2021

AbstractGas pressurized spacesuits are cumbersome, cause injuries, and make completing tasks efficiently difficult. Decreasing the gas pressure of the spacesuit is an effective method of improving mobility, but reduction in the total spacesuit pressure also results in a higher risk for decompression sickness (DCS). The risk of DCS is currently mitigated by breathing pure oxygen before the Extravehicular Activity (EVA) for up to 4 hours to remove inert gases from body tissues, but this has a negative operational impact due to the time needed to perform the prebreathe. In this paper, we review and quantify these important trade-offs between spacesuit pressure, mobility, and prebreathe time (or risk of DCS) in the context of future planetary EVAs. These trade-offs are highly dependent on the atmospheric conditions used in the space habitat or space station, and therefore, these conditions are also important considerations for future planetary exploration activities. In our analysis, we include three habitat scenarios (International Space Station: 14.7 psia, 21% O2, Adjusted Space Shuttle: 10.2 psia, 26.5% O2, and Exploration: 8.2 psia, 34% O2) to further quantify these differences. In addition, we explore these trade-offs in the context of the SmartSuit spacesuit architecture, a hybrid spacesuit with a soft robotic layer that, not only increases mobility with assistive actuators in the lower body, but it also applies 1 psia of mechanical counterpressure (MCP). The additional MCP in hybrid spacesuits can be used to supplement the gas pressure (i.e., increasing the total spacesuit pressure), therefore reducing the risk of DCS (or reduce prebreathe time). Alternatively, the MCP can be used to reduce the gas pressure (i.e., maintaining the same total spacesuit pressure), therefore increasing mobility. Finally, we propose a variable pressure concept of operations for the SmartSuit spacesuit architecture, where these two MCP applications are effectively combined during the same EVA to maximize the benefits of both configurations. Our framework quantifies critical spacesuit and habitat trade-offs for future planetary exploration, and contributes to the assessment of human health and performance during future planetary EVAs.