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991.
Jordi Sala Stéphanie Gascón David Cunillera-Montcusí Miguel Alonso Francisco Amat Luís Cancela da Fonseca Margarida Cristo Margarita Florencio Juan García-de-Lomas Margarida Machado Maria Rosa Miracle Alexandre Miró José Luis Pérez-Bote Joan Lluís Pretus Florent Prunier Javier Ripoll Juan Rueda María Sahuquillo Laura Serrano Marc Ventura David Verdiell-Cubedo Dani Boix 《Hydrobiologia》2017,784(1):81-91
The deficiency in the distributional data of invertebrate taxa is one of the major impediments acting on the bias towards the low awareness of its conservation status. The present study sets a basic framework to understand the large branchiopods distribution in the Iberian Peninsula and Balearic Islands. Since the extensive surveys performed in the late 1980s, no more studies existed updating the information for the whole studied area. The present study fills the gap, gathering together all available information on large branchiopods distribution since 1995, and analysing the effect of human population density and several landscape characteristics on their distribution, taking into consideration different spatial scales (100 m, 1 km and 10 km). In overall, 28 large branchiopod taxa (17 anostracans, 7 notostracans and 4 spinicaudatans) are known to occur in the area. Approximately 30% of the sites hosted multiple species, with a maximum of 6 species. Significant positive co-occurring species pairs were found clustered together, forming 4 different associations of large branchiopod species. In general, species clustered in the same group showed similar responses to analysed landscape characteristics, usually showing a better fit at higher spatial scales. 相似文献
992.
Trypanoxyuris (Trypanoxyuris) minutus (Schneider, 1866) among Alouatta guariba clamitans (Cabrera, 1940) in the state of Rio de Janeiro,Brazil 下载免费PDF全文
Alynne da Silva Barbosa Laís Verdan Dib Claudia M. Antunes Uchôa Otilio Machado Pereira Bastos Alcides Pissinatti 《Journal of medical primatology》2017,46(3):101-105
This study reports on infection by Trypanoxyuris (Trypanoxyuris) minutus among Alouatta guariba clamitans through biometry on adults and eggs. A total of 58 adult helminths were recovered from the small segment of the animal's large intestine. This study is the first report of this parasite among A. guariba clamitans in Rio de Janeiro. 相似文献
993.
Silvana Mara Turbino Luz Ribeiro Laís Roquete Lopes Guilherme de Paula Costa Vivian Paulino Figueiredo Deena Shrestha Aline Priscila Batista Roney Luiz de Carvalho Nicolato Fernando Luiz Pereira de Oliveira Juliana Assis Silva Gomes Andre Talvani 《Immunity & ageing : I & A》2017,14(1):6
Background
The current concept of overweight/obesity is most likely related to a combination of increased caloric intake and decreased energy expenditure. Widespread inflammation, associated with both conditions, appears to contribute to the development of some obesity-related comorbidities. Interventions that directly or indirectly target individuals at high risk of developing obesity have been largely proposed because of the increasing number of overweight/obese cases worldwide. The aim of the present study was to assess CXCL16, IL-17, and BMP-2 plasma factors in middle-aged and elderly women and relate them to an overweight or obese status. In total, 117 women were selected and grouped as eutrophic, overweight, and obese, according to anthropometric parameters. Analyses of anthropometric and circulating biochemical parameters were followed by plasma immunoassays for CXCL-16, IL-17, and BMP-2.Results
Plasma mediators increased in all overweight and obese individuals, with the exception of BMP-2 in the elderly group, whereas CXCL16 levels were shown to differentiate overweight and obese individuals. Overweight and/or obese middle-aged and elderly individuals presented with high LDL, triglycerides, and glycemia levels. Anthropometric parameters indicating increased-cardiovascular risk were positively correlated with CXCL-16, BMP-2, and IL-17 levels in overweight and obese middle-aged and elderly individuals.Conclusion
This study provides evidence that CXCL-16, IL-17, and BMP-2 are potential plasma indicators of inflammatory status in middle-aged and elderly women; therefore, further investigation of obesity-related comorbidities is recommended. CXCL16, in particular, could be a potential marker for middle-aged and elderly individuals transitioning from eutrophic to overweight body types, which represents an asymptomatic and dangerous condition.994.
Lysine acetylome profiling uncovers novel histone deacetylase substrate proteins in Arabidopsis 下载免费PDF全文
Paul J Boersema Jan‐Oliver Jost Katharina Kramer Ahmet Bakirbas Julia Sindlinger Magdalena Plöchinger Dario Leister Glen Uhrig Greg BG Moorhead Jürgen Cox Michael E Salvucci Dirk Schwarzer Matthias Mann Iris Finkemeier 《Molecular systems biology》2017,13(10)
Histone deacetylases have central functions in regulating stress defenses and development in plants. However, the knowledge about the deacetylase functions is largely limited to histones, although these enzymes were found in diverse subcellular compartments. In this study, we determined the proteome‐wide signatures of the RPD3/HDA1 class of histone deacetylases in Arabidopsis. Relative quantification of the changes in the lysine acetylation levels was determined on a proteome‐wide scale after treatment of Arabidopsis leaves with deacetylase inhibitors apicidin and trichostatin A. We identified 91 new acetylated candidate proteins other than histones, which are potential substrates of the RPD3/HDA1‐like histone deacetylases in Arabidopsis, of which at least 30 of these proteins function in nucleic acid binding. Furthermore, our analysis revealed that histone deacetylase 14 (HDA14) is the first organellar‐localized RPD3/HDA1 class protein found to reside in the chloroplasts and that the majority of its protein targets have functions in photosynthesis. Finally, the analysis of HDA14 loss‐of‐function mutants revealed that the activation state of RuBisCO is controlled by lysine acetylation of RuBisCO activase under low‐light conditions. 相似文献
995.
Michael R. La Frano Johannes F. Fahrmann Dmitry Grapov Oliver Fiehn Theresa L. Pedersen John W. Newman Mark A. Underwood Robin H. Steinhorn Stephen Wedgwood 《Metabolomics : Official journal of the Metabolomic Society》2017,13(4):32
Introduction
Neonatal pulmonary hypertension (PH) is a common manifestation of bronchopulmonary dysplasia (BPD) and contributes to increased morbidity and mortality of preterm birth. Postnatal growth restriction (PNGR) and hyperoxia are independent contributors to PH development, as indicated by our previous work in a rat model of BPD.Objective
To explore the metabolic consequences of induction of PH with hyperoxia and PNGR in a rat model of BPD.Methods
Sprague–Dawley rat pups (n?=?4/group) underwent three modes of PH induction: (1) growth restriction-induced by larger litter size; (2) hyperoxia-induced by 75% oxygen exposure; (3) combined growth restriction and hyperoxia. Primary metabolism, complex lipids, biogenic amines, and lipid mediators were characterized in plasma and lung tissue using GC- and LC-MS technologies.Results
Specific to hyperoxic induction, pulmonary metabolomics suggested increased reactive oxygen species (ROS) generation as indicated by: (1) increased indicators of β-oxidation and mitochondrial respiration; (2) changes in ROS-sensitive pathway activity and metabolites including the polyol pathway and xanthine oxidase pathways, and reduced glutathione; (3) decreased plasmalogens. Unlike the lung, circulating metabolite changes were induction mode-specific or additive in the combined modes (e.g. 1) growth-restriction reduced phosphatidylcholine; (2) hyperoxia increased oxylipins and trimethylamine-N-oxide (TMAO); (3) additive effects on 3-hydroxybutyric acid and arginine.Conclusion
The present study highlights the variety of metabolic changes that occur due to PNGR- and hyperoxia-induced PH, identifying numerous metabolites and pathways influenced by treatment-specific or combined effects. The rat model used in this study presents a robust means of uncovering the mechanisms that contribute to the pathology of PH.996.
Structural Modification of Stilbenoids from Acanthopanax leucorrhizus and Their Cytotoxic Activity 下载免费PDF全文
Hao‐Bin Hu Hai‐Peng Liang Hai‐Ming Li Ru‐Nan Yuan Jiao Sun Yun Wu La‐La Zhang Ming‐Hu Han 《化学与生物多样性》2017,14(11)
A new cis‐stilbenoid, 1,9‐dihydroxy‐10‐methoxy‐6H‐dibenzo[b,f]oxocin‐6‐one ( 2 ) was isolated from the AcOEt extract of the stem barks of Acanthopanax leucorrhizus, along with three known stilbenoids, 9‐hydroxy‐10‐methoxy‐6H‐dibenzo[b,f]oxocin‐6‐one ( 1 ), 5‐O‐methyl‐(E)‐resveratrol 3‐O‐β‐d ‐glucopyranoside ( 3 ), and (E)‐resveratrol 3‐O‐β‐d ‐xylopyranoside ( 4 ). Two derivatives ( 2a and 2b ) were synthesized by the structural modification of compound 2, which exhibited certain cytotoxic activities against HT‐29 and HeLa cell lines in vitro. All compounds were structurally characterized by comprehensive analysis of their spectroscopic data and comparison with literature information, and evaluated for their cytotoxic activities against three human tumor cell lines (HL‐60, HT‐29, and HeLa) by the standard MTT assay in vitro. The results showed that derivatives 2a and 2b exhibited strong activities than compounds 2 against HT‐29 and HeLa cell lines. 相似文献
997.
High‐Performance and Stable All‐Polymer Solar Cells Using Donor and Acceptor Polymers with Complementary Absorption 下载免费PDF全文
Zhaojun Li Wei Zhang Xiaofeng Xu Zewdneh Genene Dario Di Carlo Rasi Wendimagegn Mammo Arkady Yartsev M. R. Andersson René A. J. Janssen Ergang Wang 《Liver Transplantation》2017,7(14)
To explore the advantages of emerging all‐polymer solar cells (all‐PSCs), growing efforts have been devoted to developing matched donor and acceptor polymers to outperform fullerene‐based PSCs. In this work, a detailed characterization and comparison of all‐PSCs using a set of donor and acceptor polymers with both conventional and inverted device structures is performed. A simple method to quantify the actual composition and light harvesting contributions from the individual donor and acceptor is described. Detailed study on the exciton dissociation and charge recombination is carried out by a set of measurements to understand the photocurrent loss. It is unraveled that fine‐tuned crystallinity of the acceptor, matched donor and acceptor with complementary absorption and desired energy levels, and device architecture engineering can synergistically boost the performance of all‐PSCs. As expected, the PBDTTS‐FTAZ:PNDI‐T10 all‐PSC attains a high and stable power conversion efficiency of 6.9% without obvious efficiency decay in 60 d. This work demonstrates that PNDI‐T10 can be a potential alternative acceptor polymer to the widely used acceptor N2200 for high‐performance and stable all‐PSCs. 相似文献
998.
Chiara Merigliano Romina Burla Mattia La Torre Simona Del Giudice Hsiangling Teo Chong Wai Liew Alexandre Chojnowski Wah Ing Goh Yolanda Olmos Klizia Maccaroni Maria Giubettini Irene Chiolo Jeremy G. Carlton Domenico Raimondo Fiammetta Vernì Colin L. Stewart Daniela Rhodes Graham D. Wright Brian E. Burke Isabella Saggio 《PLoS genetics》2021,17(8)
To complete mitosis, the bridge that links the two daughter cells needs to be cleaved. This step is carried out by the endosomal sorting complex required for transport (ESCRT) machinery. AKTIP, a protein discovered to be associated with telomeres and the nuclear membrane in interphase cells, shares sequence similarities with the ESCRT I component TSG101. Here we present evidence that during mitosis AKTIP is part of the ESCRT machinery at the midbody. AKTIP interacts with the ESCRT I subunit VPS28 and forms a circular supra-structure at the midbody, in close proximity with TSG101 and VPS28 and adjacent to the members of the ESCRT III module CHMP2A, CHMP4B and IST1. Mechanistically, the recruitment of AKTIP is dependent on MKLP1 and independent of CEP55. AKTIP and TSG101 are needed together for the recruitment of the ESCRT III subunit CHMP4B and in parallel for the recruitment of IST1. Alone, the reduction of AKTIP impinges on IST1 and causes multinucleation. Our data altogether reveal that AKTIP is a component of the ESCRT I module and functions in the recruitment of ESCRT III components required for abscission. 相似文献
999.
Francesca Bianchi Elisa Sala Chiara Donadei Irene Capelli Gaetano La Manna 《World journal of stem cells》2014,6(5):644-650
Mesenchymal stem cells are currently considered as a promising tool for therapeutic application in acute kidney injury (AKI) management. AKI is characterized by acute tubular injury with rapid loss of renal function. After AKI, inflammation, oxidative stress and excessive deposition of extracellular matrix are the molecular events that ultimately cause the end-stage renal disease. Despite numerous improvement of supportive therapy, the mortality and morbidity among patients remain high. Therefore, exploring novel therapeutic options to treat AKI is mandatory. Numerous evidence in animal models has demonstrated the capability of mesenchymal stem cells (MSCs) to restore kidney function after induced kidney injury. After infusion, MSCs engraft in the injured tissue and release soluble factors and microvesicles that promote cell survival and tissue repairing. Indeed, the main mechanism of action of MSCs in tissue regeneration is the paracrine/endocrine secretion of bioactive molecules. MSCs can be isolated from several tissues, including bone marrow, adipose tissue, and blood cord; pre-treatment procedures to improve MSCs homing and their paracrine function have been also described. This review will focus on the application of cell therapy in AKI and it will summarize preclinical studies in animal models and clinical trials currently ongoing about the use of mesenchymal stem cells after AKI. 相似文献
1000.
Dario Farina Lars Arendt-Nielsen Thomas Graven-Nielsen 《Journal of applied physiology》2005,98(4):1495-1502
The motor unit twitch torque is modified by sustained contraction, but the association to changes in muscle fiber electrophysiological properties is not fully known. Thus twitch torque, muscle fiber conduction velocity, and action potential properties of single motor units were assessed in 11 subjects following an isometric submaximal contraction of the tibialis anterior muscle until endurance. The volunteers activated a target motor unit at the minimum discharge rate in eight 3-min-long contractions, three before and five after an isometric contraction at 40% of the maximal torque, sustained until endurance. Multichannel surface electromyogram signals and joint torque were averaged with the target motor unit potential as trigger. Discharge rate (mean +/- SE, 6.6 +/- 0.2 pulses/s) and interpulse interval variability (33.3 +/- 7.0%) were not different in the eight contractions. Peak twitch torque and recruitment threshold increased significantly (93 +/- 29 and 12 +/- 5%, P <0.05) in the contraction immediately after the endurance task with respect to the preendurance values (0.94 +/- 0.26 mN.m and 3.7 +/- 0.5% of the maximal torque), whereas time to peak of the twitch torque did not change (74.4 +/- 10.1 ms). Muscle fiber conduction velocity decreased and action potential duration increased in the contraction after the endurance (6.3 +/- 1.8 and 9.8 +/- 1.8%, respectively, P <0.05; preendurance values, 3.9 +/- 0.2 m/s and 11.1 +/- 0.8 ms), whereas the surface potential peak-to-peak amplitude did not change (27.1 +/- 3.1 microV). There was no significant correlation between the relative changes in muscle fiber conduction velocity or surface potential duration and in peak twitch torque (R2= 0.04 and 0.10, respectively). In conclusion, modifications in peak twitch torque of low-threshold motor units with sustained contraction are mainly determined by mechanisms not related to changes in action potential shape and in its propagation velocity. 相似文献