bluuebunny/crossref_metadata_2025_split huggingface dataset:
Alpha-ketoglutarate utilization in Saccharomyces cerevisiae: transport, compartmentation and catabolism
Authors: Zhang Jinrui , van den Herik Bas Mees , Wahl Sebastian Aljoscha 
Published: July 2020

Abstractα-Ketoglutarate (αKG) is a metabolite of the tricarboxylic acid cycle, important for biomass synthesis and a precursor for biotechnological products like 1,4-butanediol. In the eukaryote Saccharomyces cerevisiae αKG is present in different compartments. Compartmentation and (intra-)cellular transport could interfere with heterologous product pathways, generate futile cycles and reduce product yields. Batch and chemostat cultivations at low pH (≤ 5) showed that αKG can be transported, catabolized and used for biomass synthesis. The uptake mechanism of αKG was further investigated under αKG limited chemostat conditions at different pH (3, 4, 5, and 6). At very low pH (3, 4) there is a fraction of undissociated αKG that could diffuse over the periplasmic membrane. At pH 5 this fraction is very low, and the observed growth and residual concentration requires a permease/facilitated uptake mechanism of the mono-dissociated form of αKG. Consumption of αKG under mixed substrate conditions was only observed for low glucose concentrations in chemostat cultivations, suggesting that the putative αKG transporter is repressed by glucose. Fully 13C-labeled αKG was introduced as a tracer during a glucose/αKG co-feeding chemostat to trace αKG transport and utilization. The measured 13C enrichments suggest the major part of the consumed 13C αKG was used for the synthesis of glutamate, and the remainder was transported into the mitochondria and fully oxidized. There was no enrichment observed in glycolytic intermediates, suggesting that there was no gluconeogenic activity under the co-feeding conditions. 13C based flux analysis suggests that the intracellular transport is bi-directional, i.e. there is a fast exchange between the cytosol and mitochondria. The model further estimates that most intracellular αKG (88%) was present in the cytosol. Using literature reported volume fractions, the mitochondria/cytosol concentration ratio was 1.33. Such ratio will not require energy investment for transport towards the mitochondria (based on thermodynamic driving forces calculated with literature pH values). Growth on αKG as sole carbon source was observed, suggesting that S. cerevisiae is not fully Krebs-negative. Using 13C tracing and modelling the intracellular use of αKG under co-feeding conditions showed a link with biomass synthesis, transport into the mitochondria and catabolism. For the engineering of strains that use cytosolic αKG as precursor, both observed sinks should be minimized to increase the putative yields.
Static and dynamic mechanical properties and deterioration of bedding sandstone subjected to freeze–thaw cycles: considering bedding structure effect
Authors: Chang Sen , Xu Jin-Yu , Bai Er-lei , Zheng Guang-Hui , Lv Xiao-cong 
Published: July 2020

AbstractThe bedding rock widely exists in nature and its mechanical properties are complex. In this study, the Φ100 mm split Hopkinson pressure bar (SHPB), freeze–thaw(F–T) cycle test system joint with scanning electron microscope and other facilities are applied to investigate the static characteristics, impact characteristics, and damage microstructure of the bedding rock under freezing and thawing conditions. Our experimental results show that under the F–T cycle conditions, the peak point deteriorating path of the static stress–strain curve and the post-peak strain softening curve of the vertical and parallel bedding sandstone specimens have obvious anisotropic characteristics. Parallel bedding specimens have a “pressure bar” effect when loaded. Under the dynamic mechanical test, the peak stress of the vertical bedding specimen is always larger than that of the parallel bedding specimen, and the difference between the two becomes larger while the impact velocity increases. Finally, our microscopic analysis indicates that the main reason for the formation of fissures in the bedding sandstone under the F–T cycle is the cracking of the cement and the shedding of the mineral particles, while the fracture of the mineral particles rarely occurs. The results can provide theoretical guidance for geotechnical engineering in alpine regions.
Kinetic investigations of sulfite addition to flavanols
Authors: Bonaldo Federico , Guella Graziano , Mattivi Fulvio , Catorci Daniele , Arapitsas Panagiotis 
Published: July 2020

AbstractFlavanols are an important class of natural products occurring in almost all plants, fruits and vegetables; they have a great influence on wine ageing potential, astringency, colour stability and biological activities. In wine, flavanols react with sulfur dioxide ($$\hbox {SO}_2$$SO2), the most widely used preservative in oenology, leading to sulfonated products. Here we report a kinetic investigation, through LC-MS quantitative measurements carried out at different pH (3 and 4) and temperature values (23, 30, 40, 50 and $$60\, ^\circ \hbox {C}$$60∘C), of the reaction products obtained by $$\hbox {SO}_2$$SO2 addition to both monomeric (epicatechin and catechin) and dimeric flavanols (procyanidin B2 and procyanidin B3). The results proved that: (a) the major sulfonation route that leads quickly and in good yields to monomeric 4$$\beta$$β-sulfonated derivatives passes through the acid-catalysed depolymerisation of proanthocyanidins; (b) monomeric flavanols lead to the same 4$$\beta$$β-sulfonated products, although in a considerably slower manner, and also to other sulfonated regioisomers; (c) the kinetic data in our hands, in particular the temperature dependence of the observed rates, suggest the involvement of two completely different reaction mechanisms for the $$\hbox {SO}_2$$SO2 addition to dimeric and monomeric flavanol substrates; (d) direct sulfonation of epicatechin is slightly faster than that of catechin.
Lagrangian eddy kinetic energy of ocean mesoscale eddies and its application to the Northwestern Pacific
Authors: Ding Mengrong , Lin Pengfei , Liu Hailong , Hu Aixue , Liu Chuanyu 
Published: July 2020

AbstractCoherent oceanic mesoscale eddies with unique dynamical structures have great impacts on ocean transports and global climate. Eddy kinetic energy (EKE), derived from time-dependent circulation, is commonly used to study mesoscale eddies. However, there are three deficiencies of EKE when focusing on the analysis of coherent mesoscale eddies. Here, we propose a comprehensive concept—Lagrangian EKE (LEKE) as an additional metric which is a combination of gridded EKE calculated in Eulerian framework and tracked coherent mesoscale eddies in Lagrangian framework. Evidences suggest that LEKE can make up these deficiencies as an effective supplement. In this study, regional application over Northwestern Pacific Ocean is taken as an example. It clearly demonstrates that LEKE reveals more accurate and detailed characteristics of both cyclonic and anticyclonic eddies than EKE when coherent mesoscale eddies are the specific focus, such as the variation rates of kinetic energy during the eddy propagation, spatial–temporal differences of kinetic energy between cyclonic and anticyclonic eddies. Overall, using LEKE to analyze coherent mesoscale eddies gives the rise to understand the spatial–temporal contrasts between eddies with different polarities, and provides a new perspective to recognize the crucial role played by coherent mesoscale eddies in the ocean.
Quality assessment tests for tumorigenicity of human iPS cell-derived cartilage
Authors: Takei Yoshiaki , Morioka Miho , Yamashita Akihiro , Kobayashi Tomohito , Shima Nobuyuki , Tsumaki Noriyuki 
Published: July 2020

AbstractArticular cartilage damage does not heal spontaneously and causes joint dysfunction. The implantation of induced pluripotent stem cell (iPSC)-derived cartilage (iPS-Cart) is one candidate treatment to regenerate the damaged cartilage. However, concerns of tumorigenicity are associated with iPS-Cart, because the iPSC reprogramming process and long culture time for cartilage induction could increase the chance of malignancy. We evaluated the tumorigenic risks of iPS-Cart using HeLa cells as the reference. Spike tests revealed that contamination with 100 HeLa cells in 150 mg of iPS-Cart accelerated the cell growth rate. On the other hand, 150 mg of iPS-Cart without HeLa cells reached growth arrest and senescence after culture, suggesting less than 100 tumorigenic cells, assuming they behave like HeLa cells, contaminated iPS-Cart. The implantation of 10,000 or fewer HeLa cells into joint surface defects in the knee joint of nude rat did not cause tumor formation. These in vitro and in vivo studies collectively suggest that the implantation of 15 g or less iPS-Cart in the knee joint does not risk tumor formation if assuming that the tumorigenic cells in iPS-Cart are equivalent to HeLa cells and that nude rat knee joints are comparable to human knee joints in terms of tumorigenicity. However, considering the limited immunodeficiency of nude rats, the clinical amount of iPS-Cart for implantation needs to be determined cautiously.
Multiple loci linked to inversions are associated with eye size variation in species of the Drosophila virilis phylad
Authors: Reis Micael , Wiegleb Gordon , Claude Julien , Lata Rodrigo , Horchler Britta , Ha Ngoc-Thuy , Reimer Christian , Vieira Cristina P. , Vieira Jorge , Posnien Nico 
Published: July 2020

AbstractThe size and shape of organs is tightly controlled to achieve optimal function. Natural morphological variations often represent functional adaptations to an ever-changing environment. For instance, variation in head morphology is pervasive in insects and the underlying molecular basis is starting to be revealed in theDrosophilagenus for species of themelanogastergroup. However, it remains unclear whether similar diversifications are governed by similar or different molecular mechanisms over longer timescales. To address this issue, we used species of thevirilisphylad because they have been diverging fromD. melanogasterfor at least 40 million years. Our comprehensive morphological survey revealed remarkable differences in eye size and head shape among these species withD. novamexicanahaving the smallest eyes and southernD. americanapopulations having the largest eyes. We show that the genetic architecture underlying eye size variation is complex with multiple associated genetic variants located on most chromosomes. Our genome wide association study (GWAS) strongly suggests that some of the putative causative variants are associated with the presence of inversions. Indeed, northern populations ofD. americanashare derived inversions withD. novamexicanaand they show smaller eyes compared to southern ones.Intriguingly, we observed a significant enrichment of genes involved in eye development on the4thchromosome after intersecting chromosomal regions associated with phenotypic differences with those showing high differentiation amongD. americanapopulations. We propose that variants associated with chromosomal inversions contribute to both intra- and interspecific variation in eye size among species of thevirilisphylad.
Integrated transcriptomic and metabolomic analyses reveal the effects of callose deposition and multihormone signal transduction pathways on the tea plant-Colletotrichum camelliae interaction
Authors: Lu Qinhua , Wang Yuchun , Xiong Fei , Hao Xinyuan , Zhang Xinzhong , Li Nana , Wang Lu , Zeng Jianming , Yang Yajun , Wang Xinchao 
Published: July 2020

AbstractColletotrichuminfects diverse hosts, including tea plants, and can lead to crop failure. Numerous studies have reported that biological processes are involved in the resistance of tea plants toColletotrichumspp. However, the molecular and biochemical responses in the host during this interaction are unclear. Cuttings of the tea cultivar Longjing 43 (LJ43) were inoculated with a conidial suspension ofColletotrichum camelliae, and water-sprayed cuttings were used as controls. In total, 10,592 differentially expressed genes (DEGs) were identified from the transcriptomic data of the tea plants and were significantly enriched in callose deposition and the biosynthesis of various phytohormones. Subsequently, 3,555 mass spectra peaks were obtained by LC–MS detection in the negative ion mode, and 27, 18 and 81 differentially expressed metabolites (DEMs) were identified in the tea leaves at 12 hpi, 24 hpi and 72 hpi, respectively. The metabolomic analysis also revealed that the levels of the precursors and intermediate products of jasmonic acid (JA) and indole-3-acetate (IAA) biosynthesis were significantly increased during the interaction, especially when the symptoms became apparent. In conclusion, we suggest that callose deposition and various phytohormone signaling systems play important roles in the tea plant-C. camelliaeinteraction.
Metabolic effects of antihyperglycemic agents and mortality: meta-analysis of randomized controlled trials
Authors: Rados Dimitris Varvaki , Viecceli Camila , Pinto Lana Catani , Gerchman Fernando , Leitão Cristiane Bauermann , Gross Jorge Luiz 
Published: July 2020

AbstractThe effects of antihyperglycemic medications on cardiovascular events and mortality are heterogeneous and their effects on intermediate factors might explain these differences. This systematic review explores the relationship between metabolic factors, mechanism of action, and mortality effects of antihyperglycemic medications in type 2 diabetes. Randomized trials assessing the effects of antihyperglycemic medications on all-cause or cardiovascular mortality in type 2 diabetes were included. Myocardial infarction, stroke, and heart failure were secondary outcomes. The effects of medications on HbA1c, severe hypoglycemia (SH), body weight, systolic blood pressure (SBP), and mechanism of action were evaluated. Meta-analyses and meta-regressions were performed grouping studies according to the above-cited factors. All-cause mortality was lower for medications that reduced HbA1c, SH, body weight, and SBP. Decreased cardiovascular mortality was associated with lower HbA1c, SH, SBP. Myocardial infarction and stroke were also associated with favorable metabolic profile. These findings were not confirmed in meta-regression models. Medications associated with lower SH, body weight and SBP had a lower risk of heart failure. In conclusion, medications with better metabolic profile were associated with reduced all-cause and cardiovascular mortality. These findings are based on indirect comparisons and must be applied cautiously.
Plasmodium falciparum isolate with histidine-rich protein 2 gene deletion from Nyala City, Western Sudan
Authors: Boush Mohammed A. , Djibrine Moussa A. , Mussa Ali , Talib Mustafa , Maki A. , Mohammed Abdulrahman , Beshir Khalid B. , Mohamed Zeehaida , Hajissa Khalid 
Published: July 2020

AbstractIn remote areas of malaria-endemic countries, rapid diagnostic tests (RDTs) have dramatically improved parasitological confirmation of suspected malaria cases, especially when skilled microscopists are not available. This study was designed to determine the frequency of Plasmodium falciparum isolates with histidine-rich protein 2 (pfhrp2) gene deletion as one of the possible factors contributing to the failure of PfHRP2-based RDTs in detecting malaria. A total of 300 blood samples were collected from several health centres in Nyala City, Western Sudan. The performance of PfHRP2-based RDTs in relation to microscopy was examined and the PCR-confirmed samples were investigated for the presence of pfhrp2 gene. A total of 113 out of 300 patients were P. falciparum positive by microscopy. Among them, 93.81% (106 out of 113) were positives by the PfHRP2 RDTs. Seven isolates were identified as false negative on the basis of the RDTs results. Only one isolate (0.9%; 1/113) potentially has pfhrp2 gene deletion. The sensitivity and specificity of PfHRP2-based RDTs were 93.81% and 100%, respectively. The results provide insights into the pfhrp2 gene deletion amongst P. falciparum population from Sudan. However, further studies with a large and systematic collection from different geographical settings across the country are needed.
The indirect effect of peer problems on adolescent depression through nucleus accumbens volume alteration
Authors: Lee Kyung Hwa , Yoo Jae Hyun , Lee Jung , Kim Seong Hae , Han Ji Youn , Hong Soon-Beom , Shin Jiyoon , Cho Soo-Churl , Kim Jae-Won , Brent David A. 
Published: July 2020

AbstractLiterature suggests that neurobiological factors such as brain structure play an important role in linking social stress with depression in adolescence. We aimed to examine the role of subcortical volumetric alteration in the association between peer problems as one type of social stress and adolescent depression. We hypothesized that there would be indirect effects of peer problems on adolescent depression through subcortical volumetric alteration. Seventy eight adolescents with major depressive disorder (MDD) (age mean [SD] = 14.9 ± 1.5, 56 girls) and 47 healthy controls [14.3 ± 1.4, 26 girls]) participated in this study. High-resolution structural T1 images were collected using the Siemens 3T MR scanner. Subcortical volumes were segmented using the Freesurfer 6.0 package. Peer problems were assessed using the Peer-Victimization Scale and the Bullying-Behavior Scale. There was a significant indirect effect of peer problems on adolescent depression through nucleus accumbens (NAcc) volume alteration, but not through the amygdala and hippocampal volumes. This result supported our model, which stated that peer problems have indirect effects through subcortical volumetric alteration (i.e., increased NAcc volume) on adolescent depression. Our finding suggests that altered NAcc volume may serve as a pathway, through which peer problems as one type of social stressor contribute to adolescent depression.
Lipoxins, RevD1 and 9, 13 HODE as the most important derivatives after an early incident of ischemic stroke
Authors: Szczuko Małgorzata , Kotlęga Dariusz , Palma Joanna , Zembroń-Łacny Agnieszka , Tylutka Anna , Gołąb-Janowska Monika , Drozd Arleta 
Published: July 2020

AbstractThere is limited information available regarding the association of plasma free fatty acids (FFA) and inflammation mediators with ischemic stroke. At the same time, new treatment strategies are being pursued. The aim of this study was to carry out a thorough analysis of inflammation with multiple FFA-derivative mediators after and ischemic stroke and standard treatment. HPLC separations of 17 eicosanoids were performed using an Agilent Technologies 1,260 liquid chromatograph. The profiles of the esters of fatty acids were labelled by means of gas chromatography. FFA, and eicosanoid profiles in the group of patients after ischemic stroke significantly differed from the profile of the control group. Studies confirmed the involvement of derivative synthesis pathways responsible for the inflammation, especially palmitic acid (9 and 13 HODE), arachidonic acid, EPA and DHA. Arachidonic acid derivatives were synthesised on 5LOX, 15 LOX and COX pathways with the participation of prostaglandins while omega 3 derivatives strengthened the synthesis of resolvins, RevD1 in particular. The ability to accelerate the quenching of inflammation after ischemic stroke seems to be a promising strategy of stroke treatment in its early stage. In this context, our study points to lipoxins, RevD1, and 9, 13 HODE as the most important derivatives.
Red-capped mangabeys (Cercocebus torquatus) adapt their interspecific gestural communication to the recipient’s behaviour
Authors: Aychet Juliette , Pezzino Pablo , Rossard Arnaud , Bec Philippe , Blois-Heulin Catherine , Lemasson Alban 
Published: July 2020

AbstractSensitivity to recipient’s attention and responsiveness are critical markers of intentional communication. Although previous research showed that ape gestures can be intentional, few studies have yet addressed this question concerning monkeys. Here, we characterise the effect of a recipient’s presence, attentional state and responsiveness on the interspecific gestural communication of captive red-capped mangabeys (Cercocebus torquatus). Previous reports showed that they produced learnt begging gestures towards a human recipient preferentially when the latter was facing them. We used here a novel setup that allows subjects to move around an experimenter and to use different modalities (visual and acoustic) to communicate. We found that when the recipient was not facing them, mangabeys moved to a position in the visual field of their recipient rather than using attention-getters. Interestingly, unlike apes, they did not elaborate their communication visually or acoustically when the experimenter did not respond favourably to their begging. However, our results may suggest that begging gestures were goal-directed, since mangabeys inhibited them when the experimenter was not available to answer immediately (i.e. give a reward). Overall, red-capped mangabeys’ interspecific visual communication presented intentionality features, but their use of begging gestures was less flexible than that of great apes in similar situations.
Identification of epidermal differentiation genes of the tuatara provides insights into the early evolution of lepidosaurian skin
Authors: Holthaus Karin Brigit , Alibardi Lorenzo , Tschachler Erwin , Eckhart Leopold 
Published: July 2020

AbstractThe tuatara (Sphenodon punctatus) is the phylogenetically closest relative of squamates (including lizards and snakes) from which it diverged around 250 million years ago. Together, they constitute the clade Lepidosauria. Fully terrestrial vertebrates (amniotes) form their skin barrier to the environment under the control of a gene cluster, termed the epidermal differentiation complex (EDC). Here we identified EDC genes in the genome of the tuatara and compared them to those of other amniotes. The organization of the EDC and proteins encoded by EDC genes are most similar in the tuatara and squamates. A subcluster of lepidosaurian EDC genes encodes corneous beta-proteins (CBPs) of which three different types are conserved in the tuatara. Small proline-rich proteins have undergone independent expansions in the tuatara and some, but not all subgroups of squamates. Two genes encoding S100 filaggrin-type proteins (SFTPs) are expressed during embryonic skin development of the tuatara whereas SFTP numbers vary between 1 and 3 in squamates. Our comparative analysis of the EDC in the tuatara genome suggests that many molecular features of the skin that were previously identified in squamates have evolved prior to their divergence from the lineage leading to the tuatara.
Genetic algorithm for the location control of femtosecond laser filament
Authors: Zhang Zhi , Kosareva Olga , Zhang Nan , Lin Lie , Liu Weiwei 
Published: July 2020

AbstractAn adaptive method based on the genetic algorithm (GA) is proposed to control the location of femtosecond laser filament. To verify the feasibility of this method, the simulation results obtained through the GA method are compared with those by the chirp method when femtosecond laser pulses with different pulse energies are used. It is found that the intensity profile and the phase of the femtosecond laser pulses obtained by the GA method are nearly identical to those obtained by the chirp method. It demonstrates that the GA adaptive control method can accurately control the position of the starting point of the filament in the femtosecond laser filamentation.