bluuebunny/crossref_metadata_2025_split huggingface dataset:
Survival strategies of an anoxic microbial ecosystem in Lake Untersee, a potential analog for Enceladus
Authors: Wagner Nicole Yasmin , Andersen Dale T. , Hahn Aria S. , Johnson Sarah Stewart 
Published: May 2022

AbstractLake Untersee located in Eastern Antarctica, is a perennially ice-covered lake. At the bottom of its southern basin lies 20 m of anoxic, methane rich, stratified water, making it a good analog for Enceladus, a moon of Saturn. Here we present the first metagenomic study of this basin and detail the community composition and functional potential of the microbial communities at 92 m, 99 m depths and within the anoxic sediment. A diverse and well-populated microbial community was found, presenting the potential for Enceladus to have a diverse and abundant community. We also explored methanogenesis, sulfur metabolism, and nitrogen metabolism, given the potential presence of these compounds on Enceladus. We found an abundance of these pathways offering a variety of metabolic strategies. Additionally, the extreme conditions of the anoxic basin make it optimal for testing spaceflight technology and life detection methods for future Enceladus exploration.
Modified lipid metabolism and cytosolic phospholipase A2 activation in mesangial cells under pro-inflammatory conditions
Authors: Boi Roberto , Ebefors Kerstin , Henricsson Marcus , Borén Jan , Nyström Jenny 
Published: May 2022

AbstractDiabetic kidney disease is a consequence of hyperglycemia and other complex events driven by early glomerular hemodynamic changes and a progressive expansion of the mesangium. The molecular mechanisms behind the pathophysiological alterations of the mesangium are yet to be elucidated. This study aimed at investigating whether lipid signaling might be the missing link. Stimulation of human mesangial cells with high glucose primed the inflammasome-driven interleukin 1 beta (IL-1β) secretion, which in turn stimulated platelet-derived growth factor (PDGF-BB) release. Finally, PDGF-BB increased IL-1β secretion synergistically. Both IL-1β and PDGF-BB stimulation triggered the formation of phosphorylated sphingoid bases, as shown by lipidomics, and activated cytosolic phospholipase cPLA2, sphingosine kinase 1, cyclooxygenase 2, and autotaxin. This led to the release of arachidonic acid and lysophosphatidylcholine, activating the secretion of vasodilatory prostaglandins and proliferative lysophosphatidic acids. Blocking cPLA2 release of arachidonic acid reduced mesangial cells proliferation and prostaglandin secretion. Validation was performed in silico using the Nephroseq database and a glomerular transcriptomic database. In conclusion, hyperglycemia primes glomerular inflammatory and proliferative stimuli triggering lipid metabolism modifications in human mesangial cells. The upregulation of cPLA2 was critical in this setting. Its inhibition reduced mesangial secretion of prostaglandins and proliferation, making it a potential therapeutical target.
Sophisticated expression responses of ZNT1 and MT in response to changes in the expression of ZIPs
Authors: Nagamatsu Shino , Nishito Yukina , Yuasa Hana , Yamamoto Nao , Komori Taiki , Suzuki Takuya , Yasui Hiroyuki , Kambe Taiho 
Published: May 2022

AbstractThe zinc homeostatic proteins Zn transporter 1 (ZNT1) and metallothionein (MT) function in dampening increases in cytosolic zinc concentrations. Conversely, the expression of ZNT1 and MT is expected to be suppressed during decreases in cytosolic zinc concentrations. Thus, ZNT1/MT homeostatic responses are considered to be essential for maintaining cellular zinc homeostasis because cellular zinc concentrations are readily altered by changes in the expression of several Zrt-/Irt-like proteins (ZIPs) under both physiological and pathological conditions. However, this notion remains to be tested experimentally. Here, we investigated the aforementioned homeostatic process by analyzing ZNT1 and MT protein expression in response to ZIP expression. Overexpression of cell-surface-localized ZIPs, such as ZIP4 and ZIP5, increased the cellular zinc content, which caused an increase in the expression of cell-surface ZNT1 and cytosolic MT in the absence of zinc supplementation in the culture medium. By contrast, elimination of the overexpressed ZIP4 and ZIP5 resulted in decreased expression of ZNT1 but not MT, which suggests that differential regulation of ZNT1 and MT expression at the protein level underlies the homeostatic responses necessary for zinc metabolism under certain conditions. Moreover, increased expression of apically localized ZIP4 facilitated basolateral ZNT1 expression in polarized cells, which indicates that such a coordinated expression mechanism is crucial for vectorial transcellular transport. Our results provide novel insights into the physiological maintenance of cellular zinc homeostasis in response to alterations in cytosolic zinc concentrations caused by changes in the expression of ZIPs.
Assessing positive and negative valence systems to refine animal models of bipolar disorders: the example of GBR 12909-induced manic phenotype
Authors: Bigot Mathilde , Vicq Eleonore , Lledo Pierre-Marie , Alonso Mariana , Henry Chantal 
Published: May 2022

AbstractBipolar disorders are defined by recurrences of depressive and manic episodes. The pathophysiology is still unknown, and translating clinical symptoms into behaviors explorable in animal models is challenging. Animal models of bipolar disorder do not exist because cyclicity of the disease is impossible to mimic, and it is therefore necessary to study mania and depression models separately. Beyond mood, emotional biases differentiate bipolar states in humans. Mania is associated with positive biases, e.g. emotional stimuli become more rewarding and less aversive, and the opposite for depression. We propose to assess behavioral hedonic responses to innately appetitive and aversive olfactory and gustatory cues in mice as proxies for the assigned emotional valence. A mania model is therefore supposed to exhibit positive hedonic bias. Using the GBR 12909 mania model, we observed the classical hyperactivity phenotype, along with low depressive-like but high anxiety-like behaviors. Unexpectedly, GBR 12909-treated mice exhibited strong negative hedonic biases. Consequently, the GBR 12909 model of mania might not be appropriate for studying emotional disturbances associated with mania states. We propose olfactory and gustatory preference tests as crucial assessment for positive and negative valence biases, necessary for precisely characterizing animal models of bipolar disorders.
Ketone body and FGF21 coordinately regulate fasting-induced oxidative stress response in the heart
Authors: Kawakami Ryo , Sunaga Hiroaki , Iso Tatsuya , Kaneko Ryosuke , Koitabashi Norimichi , Obokata Masaru , Harada Tomonari , Matsui Hiroki , Yokoyama Tomoyuki , Kurabayashi Masahiko 
Published: May 2022

AbstractKetone body β-hydroxybutyrate (βOHB) and fibroblast growth factor-21 (FGF21) have been proposed to mediate systemic metabolic response to fasting. However, it remains elusive about the signaling elicited by ketone and FGF21 in the heart. Stimulation of neonatal rat cardiomyocytes with βOHB and FGF21 induced peroxisome proliferator-activated receptor α (PPARα) and PGC1α expression along with the phosphorylation of LKB1 and AMPK. βOHB and FGF21 induced transcription of peroxisome proliferator-activated receptor response element (PPRE)-containing genes through an activation of PPARα. Additionally, βOHB and FGF21 induced the expression of Nrf2, a master regulator for oxidative stress response, and catalase and Ucp2 genes. We evaluated the oxidative stress response gene expression after 24 h fast in global Fgf21-null (Fgf21−/−) mice, cardiomyocyte-specific FGF21-null (cmFgf21−/−) mice, wild-type (WT), and Fgf21fl/fl littermates. Fgf21−/− mice but not cmFgf21−/− mice had unexpectedly higher serum βOHB levels, and higher expression levels of PPARα and oxidative stress response genes than WT mice or Fgf21fl/fl littermates. Notably, expression levels of oxidative stress response genes were significantly correlated with serum βOHB and PGC1α levels in both WT and Fgf21−/− mice. These findings suggest that fasting-induced βOHB and circulating FGF21 coordinately regulate oxidative stress response gene expression in the heart.
Evidence against a contribution of the CCAAT-enhancer binding protein homologous protein (CHOP) in mediating neurotoxicity in rTg4510 mice
Authors: Criado-Marrero Marangelie , Blazier Danielle M. , Gould Lauren A. , Gebru Niat T. , Rodriguez Ospina Santiago , Armendariz Debra S. , Darling April L. , Beaulieu-Abdelahad David , Blair Laura J. 
Published: May 2022

AbstractTau accumulation and progressive loss of neurons are associated with Alzheimer’s disease (AD). Aggregation of tau has been associated with endoplasmic reticulum (ER) stress and the activation of the unfolded protein response (UPR). While ER stress and the UPR have been linked to AD, the contribution of these pathways to tau-mediated neuronal death is still unknown. We tested the hypothesis that reducing C/EBP Homologous Protein (CHOP), a UPR induced transcription factor associated with cell death, would mitigate tau-mediated neurotoxicity through the ER stress pathway. To evaluate this, 8.5-month-old male rTg4510 tau transgenic mice were injected with a CHOP-targeting or scramble shRNA AAV9 that also expressed EGFP. Following behavioral assessment, brain tissue was collected at 12 months, when ER stress and neuronal loss is ongoing. No behavioral differences in locomotion, anxiety-like behavior, or learning and memory were found in shCHOP mice. Unexpectedly, mice expressing shCHOP had higher levels of CHOP, which did not affect neuronal count, UPR effector (ATF4), or tau tangles. Overall, this suggests that CHOP is a not a main contributor to neuronal death in rTg4510 mice. Taken together with previous studies, we conclude that ER stress, including CHOP upregulation, does not worsen outcomes in the tauopathic brain.
FGF21-FGFR4 signaling in cardiac myocytes promotes concentric cardiac hypertrophy in mouse models of diabetes
Authors: Yanucil Christopher , Kentrup Dominik , Li Xueyi , Grabner Alexander , Schramm Karla , Martinez Eliana C. , Li Jinliang , Campos Isaac , Czaya Brian , Heitman Kylie , Westbrook David , Wende Adam R. , Sloan Alexis , Roche Johanna M. , Fornoni Alessia , Kapiloff Michael S. , Faul Christian 
Published: May 2022

AbstractFibroblast growth factor (FGF) 21, a hormone that increases insulin sensitivity, has shown promise as a therapeutic agent to improve metabolic dysregulation. Here we report that FGF21 directly targets cardiac myocytes by binding β-klotho and FGF receptor (FGFR) 4. In combination with high glucose, FGF21 induces cardiac myocyte growth in width mediated by extracellular signal-regulated kinase 1/2 (ERK1/2) signaling. While short-term FGF21 elevation can be cardio-protective, we find that in type 2 diabetes (T2D) in mice, where serum FGF21 levels are elevated, FGFR4 activation induces concentric cardiac hypertrophy. As T2D patients are at risk for heart failure with preserved ejection fraction (HFpEF), we propose that induction of concentric hypertrophy by elevated FGF21-FGFR4 signaling may constitute a novel mechanism promoting T2D-associated HFpEF such that FGFR4 blockade might serve as a cardio-protective therapy in T2D. In addition, potential adverse cardiac effects of FGF21 mimetics currently in clinical trials should be investigated.
Synthesis, characterization and application of organoclays for adsorptive desulfurization of fuel oil
Authors: Saeed Muhammad , Riaz Aqsa , Intisar Azeem , Iqbal Zafar Mazhar , Fatima Humaria , Howari Haidar , Alhodaib Aiyeshah , Waseem Amir 
Published: May 2022

AbstractThe present study encompasses the application of cost effective, organo-modified bentonite material for efficient desulfurization of model oil and real fuel. For the adsorptive desulfurization of oil, dibenzothiophene (DBT) was used as model compound. Various experimental parameters (time, temperature, adsorbent-amount and DBT concentration) were thoroughly investigated. The synthesized material was characterized via X-ray diffraction (XRD), X-ray Fluorescence (XRF), Scanning electron microscopy (SEM), Energy dispersive x-ray (EDX), Thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR). The modification exhibits the increase in interlayer spacing of clay as confirmed from XRD and modified material shows interesting morphology as compared to unmodified bentonite. The results showed that > 90% of DBT removal was achieved under optimized conditions for B-BTC, B-BTB and B-DSS and > 80% for B-BEHA, for model fuel oil which are greater than unmodified clay (< 45%). Additionally, the findings from desulfurization of real fuel oil declare that 96.76% and 95.83% removal efficiency was achieved for kerosene and diesel oil respectively, at optimized conditions and fuel properties follow ASTM specifications. The obtained findings well fitted with thermodynamic, isothermal (Langmuir) with adsorption capacity (70.8 (B-BTC), 66 (B-BTB), 61.2 (B-DSS) and 55.2 (B-BEHA) in mg/g) and pseudo-second-order kinetics. In thermodynamic studies, negative sign ($$\Delta G^\circ )$$

Δ

G
∘

)

specifies the spontaneity whereas, $$\left(\Delta H^\circ \right)$$

Δ

H
∘

endothermic and positive sign $$(\Delta S^\circ )$$

(
Δ

S
∘

)

show randomness after DBT adsorption onto organoclay.
Health burden in type 2 diabetes and prediabetes in The Maastricht Study
Authors: Veugen Marja G. J. , Onete Veronica G. , Henry Ronald M. A. , Brunner-La Rocca Hans-Peter , Koster Annemarie , Dagnelie Pieter C. , Schaper Nicolaas C. , Sep Simone J. S. , van der Kallen Carla J. H. , van Boxtel Martin P. J. , Reesink Koen D. , Schouten Johannes S. , Savelberg Hans H. C. M. , Köhler Sebastian , Verhey Frans R. , van den Bergh Joop P. W. , Schram Miranda T. , Stehouwer Coen D. A. 
Published: May 2022

AbstractMortality in type 2 diabetes, is determined not only by classical complications, but also by comorbidities, and is linked to hyperglycaemia and apparent even in prediabetes. We aimed to comprehensively investigate, in a population-based cohort, health burden defined as the presence of comorbidities in addition to classical complications and cardiometabolic risk factors, in not only type 2 diabetes but also prediabetes. Such population-based study has not been performed previously. Extensive phenotyping was performed in 3,410 participants of the population-based Maastricht Study (15.0% prediabetes and 28.6% type 2 diabetes) to assess presence of 17 comorbidities, six classical complications, and ten cardiometabolic risk factors. These were added up into individual and combined sum scores and categorized. Group differences were studied with multinomial regression analyses adjusted for age and sex. Individuals with type 2 diabetes and prediabetes, as compared to normal glucose metabolism (NGM), had greater comorbidities, classical complications, cardiometabolic risk factors and combined sum scores (comorbidities sum score ≥ 3: frequencies (95% CI) 61.5% (57.6;65.4) and 41.2% (36.5;45.9) vs. 25.4% (23.5;27.4), p-trend < 0.001; classical complications ≥ 2 (26.6% (23.1;30.1; P < 0.001 vs. NGM) and 10.1% (7.8;12.7; P = 0.065 vs NGM) vs. 8.0% (6.9;9.3)); cardiometabolic risk factors ≥ 6 (39.7% (35.9;43.4) and 28.5% (24.5;32.6) vs. 14.0% (12.5;15.6); p-trend < 0.001); combined ≥ 8 (66.6% (62.7;70.5) and 48.4% (43.7;53.1) vs. 26.0%(24.1;28.0), p-trend < 0.001). Type 2 diabetes and prediabetes health burden was comparable to respectively 32 and 14 years of ageing. Our population-based study shows, independently of age and sex, a considerable health burden in both type 2 diabetes and prediabetes, which to a substantial extent can be attributed to comorbidities in addition to classical complications and cardiometabolic risk factors. Our findings emphasize the necessity of comorbidities’ awareness in (pre)diabetes and for determining the exact role of hyperglycaemia in the occurrence of comorbidities.
Spatial maps and oscillations in the healthy hippocampus of Octodon degus, a natural model of sporadic Alzheimer’s disease
Authors: Mugnaini Matias , Polania Diana , Diaz Yannina , Ezquer Marcelo , Ezquer Fernando , Deacon Robert M. J. , Cogram Patricia , Kropff Emilio 
Published: May 2022

AbstractThe Octodon degus is a South American rodent that is receiving increased attention as a potential model of aging and sporadic late-onset Alzheimer’s disease (AD). Impairments in spatial memory tasks in Octodon degus have been reported in relation to either advanced AD-like disease or hippocampal lesion, opening the way to investigate how the function of hippocampal networks affects behavior across AD stages. However, no characterization of hippocampal electrophysiology exists in this species. Here we describe in young, healthy specimens the activity of neurons and local field potential rhythms during spatial navigation tasks with and without objects. Our findings show similarities between the Octodon degus and laboratory rodents. First, place cells with characteristics similar to those found in rats and mice exist in the CA1 subfield of the Octodon degus. Second, the introduction of objects elicits novelty-related exploration and an increase in activity of CA1 cells, with location specific and unspecific components. Third, oscillations of the local field potential are organized according to their spectral content into bands similar to those found in laboratory rodents. These results suggest a common framework of underlying mechanisms, opening the way to future studies of hippocampal dysfunction in this species associated to aging and disease.
Electron energization dynamics in interaction of self-generated magnetic vortices in upstream of collisionless electron/ion shocks
Authors: Naseri N. , Bochkarev S. G. , Bychenkov V. Y. , Khudik V. , Shvets G. 
Published: May 2022

AbstractRelativistic collisionless shocks are considered responsible for particle energization mechanisms leading to particle acceleration. While electron energization in shock front region of electron/ion collisionless shocks are the most studied, the mechanism of electron energization in interaction with self-generated magnetic vortices (MVs) in the upstream region is still unclear. We investigate electron energization mechanism in the upstream region of electron/ion relativistic collisionless shocks, using two dimensional particle-in-cell (PIC) simulations. We discuss mechanism of electron energization which takes place in the upstream region of the shock, where the counter stream particles interact with incoming flow. The energy gain of electrons happens during their interaction with evolving fields of self-generated magnetic vortices in this region. Three Fermi-like electron energization scenarios are discussed. Stochastic acceleration of electrons in interaction with fields of MV leads to anisotropic heating of fast electrons due to diffusion in the momentum space of electrons and, finally, synergetic effect of evolving fields of MVs leads to the formation of a power-law tail of supra-thermal particles.
Dynamic graph convolutional network for assembly behavior recognition based on attention mechanism and multi-scale feature fusion
Authors: Chen Chengjun , Zhao Xicong , Wang Jinlei , Li Dongnian , Guan Yuanlin , Hong Jun 
Published: May 2022

AbstractIntelligent recognition of assembly behaviors of workshop production personnel is crucial to improve production assembly efficiency and ensure production safety. This paper proposes a graph convolutional network model for assembly behavior recognition based on attention mechanism and multi-scale feature fusion. The proposed model learns the potential relationship between assembly actions and assembly tools for recognizing assembly behaviors. Meanwhile, the introduction of an attention mechanism helps the network to focus on the key information in assembly behavior images. Besides, the multi-scale feature fusion module is introduced to enable the network to better extract image features at different scales. This paper constructs a data set containing 15 types of workshop production behaviors, and the proposed assembly behavior recognition model is tested on this data set. The experimental results show that the proposed model achieves good recognition results, with an average assembly recognition accuracy of 93.1%.
Quantitative inspiratory–expiratory chest CT findings in COVID-19 survivors at the 6-month follow-up
Authors: Jia Xi , Han Xiaoyu , Cao Yukun , Fan Yanqing , Yuan Mei , Li Yumin , Gu Jin , Zheng Yuting , Wang Li , Qu Yali , Shi Heshui 
Published: May 2022

AbstractWe evaluated pulmonary sequelae in COVID-19 survivors by quantitative inspiratory–expiratory chest CT (QCT) and explored abnormal pulmonary diffusion risk factors at the 6-month follow-up. This retrospective study enrolled 205 COVID-19 survivors with baseline CT data and QCT scans at 6-month follow-up. Patients without follow-up pulmonary function tests were excluded. All subjects were divided into group 1 (carbon monoxide diffusion capacity [DLCO] < 80% predicted, n = 88) and group 2 (DLCO ≥ 80% predicted, n = 117). Clinical characteristics and lung radiological changes were recorded. Semiquantitative total CT score (0–25) was calculated by adding five lobes scores (0–5) according to the range of lesion involvement (0: no involvement; 1: < 5%; 2: 5–25%; 3: 26–50%; 4: 51–75%; 5: > 75%). Data was analyzed by two-sample t-test, Spearman test, etc. 29% survivors showed air trapping by follow-up QCT. Semiquantitative CT score and QCT parameter of air trapping in group 1 were significantly greater than group 2 (p < 0.001). Decreased DLCO was negatively correlated with the follow-up CT score for ground-glass opacity (r = − 0.246, p = 0.003), reticulation (r = − 0.206, p = 0.002), air trapping (r = − 0.220, p = 0.002) and relative lung volume changes (r = − 0.265, p = 0.001). COVID-19 survivors with lung diffusion deficits at 6-month follow-up tended to develop air trapping, possibly due to small-airway impairment.
Nonlocal models in the analysis of brain neurodegenerative protein dynamics with application to Alzheimer’s disease
Authors: Pal Swadesh , Melnik Roderick 
Published: May 2022

AbstractIt is well known that today nearly one in six of the world’s population has to deal with neurodegenerative disorders. While a number of medical devices have been developed for the detection, prevention, and treatments of such disorders, some fundamentals of the progression of associated diseases are in urgent need of further clarification. In this paper, we focus on Alzheimer’s disease, where it is believed that the concentration changes in amyloid-beta and tau proteins play a central role in its onset and development. A multiscale model is proposed to analyze the propagation of these concentrations in the brain connectome. In particular, we consider a modified heterodimer model for the protein–protein interactions. Higher toxic concentrations of amyloid-beta and tau proteins destroy the brain cell. We have studied these propagations for the primary and secondary and their mixed tauopathies. We model the damage of a brain cell by the nonlocal contributions of these toxic loads present in the brain cells. With the help of rigorous analysis, we check the stability behaviour of the stationary points corresponding to the homogeneous system. After integrating the brain connectome data into the developed model, we see that the spreading patterns of the toxic concentrations for the whole brain are the same, but their concentrations are different in different regions. Also, the time to propagate the damage in each region of the brain connectome is different.