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https://www.readbyqxmd.com/read/28103523/anthropogenic-chemical-cues-can-alter-the-swimming-behaviour-of-juvenile-stages-of-a-temperate-fish
#1
Carlos Díaz-Gil, Lucy Cotgrove, Sarah Louise Smee, David Simón-Otegui, Hilmar Hinz, Amalia Grau, Miquel Palmer, Ignacio A Catalán
Human pressure on coastal areas is affecting essential ecosystems including fish nursery habitats. Among these anthropogenic uses, the seasonal increment in the pressure due to leisure activities such as coastal tourism and yachting is an important environmental stressor in many coastal zones. These pressures may elicit understudied impacts due to, for example, sunscreens or other seasonal pollutants. The island of Majorca, northwest Mediterranean Sea, experiences one of the highest number of tourist visits per capita in the world, thus the surrounding coastal habitat is subject to high anthropogenic seasonal stress...
January 6, 2017: Marine Environmental Research
https://www.readbyqxmd.com/read/28103280/formulation-general-features-and-global-calibration-of-a-bioenergetically-constrained-fishery-model
#2
David A Carozza, Daniele Bianchi, Eric D Galbraith
Human exploitation of marine resources is profoundly altering marine ecosystems, while climate change is expected to further impact commercially-harvested fish and other species. Although the global fishery is a highly complex system with many unpredictable aspects, the bioenergetic limits on fish production and the response of fishing effort to profit are both relatively tractable, and are sure to play important roles. Here we describe a generalized, coupled biological-economic model of the global marine fishery that represents both of these aspects in a unified framework, the BiOeconomic mArine Trophic Size-spectrum (BOATS) model...
2017: PloS One
https://www.readbyqxmd.com/read/28103258/revisiting-greek-propolis-chromatographic-analysis-and-antioxidant-activity-study
#3
Konstantinos M Kasiotis, Pelagia Anastasiadou, Antonis Papadopoulos, Kyriaki Machera
Propolis is a bee product that has been extensively used in alternative medicine and recently has gained interest on a global scale as an essential ingredient of healthy foods and cosmetics. Propolis is also considered to improve human health and to prevent diseases such as inflammation, heart disease, diabetes and even cancer. However, the claimed effects are anticipated to be correlated to its chemical composition. Since propolis is a natural product, its composition is consequently expected to be variable depending on the local flora alignment...
2017: PloS One
https://www.readbyqxmd.com/read/28103011/discovery-of-a-phosphonoacetic-acid-derived-natural-product-by-pathway-refactoring
#4
Todd S Freestone, Kou-San Ju, Bin Wang, Huimin Zhao
The activation of silent natural product gene clusters is a synthetic biology problem of great interest. As the rate at which gene clusters are identified outpaces the discovery rate of new molecules, this unknown chemical space is rapidly growing, as too are the rewards for developing technologies to exploit it. One class of natural products that has been underrepresented is phosphonic acids, which have important medical and agricultural uses. Hundreds of phosphonic acid biosynthetic gene clusters have been identified encoding for unknown molecules...
January 19, 2017: ACS Synthetic Biology
https://www.readbyqxmd.com/read/28102966/histone-deacetylase-2-is-decreased-in-peripheral-blood-pro-inflammatory-cd8-t-and-nkt-like-lymphocytes-following-lung-transplant
#5
Greg Hodge, Sandra Hodge, Chien-Li Holmes-Liew, Paul N Reynolds, Mark Holmes
BACKGROUND AND OBJECTIVE: Immunosuppression therapy following lung transplantation fails to prevent chronic rejection in many patients, which is associated with lack of suppression of cytotoxic mediators and pro-inflammatory cytokines in peripheral blood T and natural killer T (NKT)-like cells. Histone acetyltransferases (HATs) and histone deacetylases (HDACs) upregulate/downregulate pro-inflammatory gene expression, respectively; however, differences in the activity of these enzymes following lung transplant are unknown...
February 2017: Respirology: Official Journal of the Asian Pacific Society of Respirology
https://www.readbyqxmd.com/read/28102779/long-term-dust-aerosol-production-from-natural-sources-in-iceland
#6
Pavla Dagsson-Waldhauserova, Olafur Arnalds, Haraldur Olafsson
: Iceland is a volcanic island in the North Atlantic Ocean with maritime climate. In spite of moist climate, large areas are with limited vegetation cover where >40% of Iceland is classified with considerable to very severe erosion and 21% of Iceland is volcanic sandy deserts. Not only do natural emissions from these sources influenced by strong winds affect regional air quality in Iceland ("Reykjavik haze"), but dust particles are transported over the Atlantic ocean and Arctic Ocean >1000 km at times...
February 2017: Journal of the Air & Waste Management Association
https://www.readbyqxmd.com/read/28102675/mechanistic-elucidation-of-zirconium-catalyzed-direct-amidation
#7
Helena Lundberg, Fredrik Tinnis, Jiji Zhang, Andrés G Algarra, Fahmi Himo, Hans Adolfsson
The mechanism of the zirconium-catalyzed condensation of carboxylic acids and amines for direct formation of amides was studied using kinetics, NMR-spectroscopy and DFT-calculations. The reaction is found to be first order with respect to catalyst and has a positive rate dependence on amine concentration and a negative rate dependence on carboxylic acid concentration. Kinetic experiments using Reaction Progress Kinetic Analysis (RPKA) protocols demonstrate that inhibition of the catalyst by the amide product can be avoided using a high amine concentration...
January 19, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28102673/total-synthesis-of-%C3%A2-berkeleyone-a
#8
Masha Elkin, Suzanne M Szewczyk, Anthony C Scruse, Timothy R Newhouse
A 13-step total synthesis of the fungal meroterpenoid berkeleyone A is reported. The molecular skeleton is formed using the first examples of two critical construction reactions: 1) an epoxide-initiated, β-ketoester-terminated polycyclization, and 2) an isomerization-cyclization cascade to generate the remaining bicyclo[3.3.1]nonane framework. The resulting 6-step synthesis of the carbocyclic core of the berkeleyone natural products has been used to access protoaustinoid A and berkeleyone A, and will aid future biosynthetic investigations into the origin of related natural products...
January 19, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28102546/ataluren-and-similar-compounds-specific-therapies-for-premature-termination-codon-class-i-mutations-for-cystic-fibrosis
#9
REVIEW
Aisha A Aslam, Colin Higgins, Ian P Sinha, Kevin W Southern
BACKGROUND: Cystic fibrosis is a common life-shortening genetic disorder in the Caucasian population (less common in other ethnic groups) caused by the mutation of a single gene that codes for the production of the cystic fibrosis transmembrane conductance regulator protein. This protein coordinates the transport of salt (and bicarbonate) across cell surfaces and the mutation most notably affects the airways. In the lungs of people with cystic fibrosis, defective protein results in a dehydrated surface liquid and compromised mucociliary clearance...
January 19, 2017: Cochrane Database of Systematic Reviews
https://www.readbyqxmd.com/read/28102400/using-chiral-ionic-liquid-additives-to-enhance-asymmetric-induction-in-a-diels-alder-reaction
#10
P Goodrich, H Q Nimal Gunaratne, L Hall, Y Wang, L Jin, M J Muldoon, A P C Ribeiro, A J L Pombeiro, V I Pârvulescu, P Davey, C Hardacre
A bis-oxazoline ligand has been complexed using Cu(ii) and Zn(ii) trifluoromethanesulfonate and a range of chiral ionic liquid (CIL) additives based on natural products were used as a co-catalyst for a Diels-Alder reaction. The catalytic performance of these systems was compared for the asymmetric Diels-Alder reaction between N-acryloyloxazolidinone and cyclopentadiene with and without the presence of a CIL additive. In the absence of the CIL, both catalysts resulted in low enantioselectivities in conventional solvents and ionic liquids...
January 19, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28102379/the-pyrrole-ring-%C3%AE-2-hapticity-bridged-binuclear-tricarbonyl-mo-0-and-w-0-complexes-catalysis-of-regioselective-hydroamination-reactions-and-dft-calculations
#11
Vikesh Kumar Jha, Ganesan Mani, Yogeswara Rao Davuluri, Anakuthil Anoop
Following the report of the ferrocene structure, metal complexes containing the heteroatom-substituted cyclopentadienyl (Cp) analogue, that is the η(5) pyrrolyl ligand, have been reported. While the Cp ligand continues to be a favorite ligand in organometallics, the transition metal chemistry of the pyrrolyl ligand is still in the developing stage. In view of this, we carried out the reaction between the multidentate ligand 2,3,4,5-tetrakis(3,5-dimethylpyrazolylmethyl)pyrrole (LH) and Mo(CO)6 or [W(CO)3(CH3CN)3] and isolated two new binuclear tricarbonyl Mo(0) and W(0) complexes, [Mo2(CO)6(μ-η(2):η(2)-LH-κ(4)N)] (1) and [W2(CO)6(μ-η(2):η(2)-LH-κ(4)N)] (2)...
January 19, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28102075/molecular-features-of-humic-acids-and-fulvic-acids-from-contrasting-environments
#12
Judith Schellekens, Peter Buurman, Karsten Kalbitz, Andre van Zomeren, Pablo Vidal-Torrado, Chiara Cerli, Rob N J Comans
Insight in the molecular structure of humic acid (HA) and fulvic acid (FA) can contribute to identify relationships between their molecular properties, and further our quantitative abilities to model important organic matter functions such as metal complexation and association with mineral surfaces. Pyrolysis gas chromatography/mass spectrometry (Py-GC-MS) is used to compare the molecular composition of HA and FA. A systematic comparison was obtained by using samples from different environmental sources, including solid and aqueous samples from both natural and waste sources...
January 19, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28101901/cyto-genotoxicity-and-oxidative-stress-in-common-carp-cyprinus-carpio-exposed-to-a-mixture-of-ibuprofen-and-diclofenac
#13
Hariz Islas-Flores, Leobardo Manuel Gómez-Oliván, Marcela Galar-Martínez, Esmeralda Michelle Sánchez-Ocampo, Nely SanJuan-Reyes, Mariana Ortíz-Reynoso, Octavio Dublán-García
Thirty million people worldwide consume each day nonsteroidal anti-inflammatory drugs (NSAIDs), a heterogeneous group of pharmaceuticals used for its analgesic, antipyretic, and anti-inflammatory properties. Recent studies report high NSAID concentrations in wastewater treatment plant effluents, in surface, ground, and drinking water, and in sediments. NSAIDs are also known to induce toxicity on aquatic organisms. However, toxicity in natural ecosystems is not usually the result of exposure to a single substance but to a mixture of toxic agents, yet only a few studies have evaluated the toxicity of mixtures...
January 19, 2017: Environmental Toxicology
https://www.readbyqxmd.com/read/28101858/coiled-coil-design-updated-and-upgraded
#14
Derek N Woolfson
α-Helical coiled coils are ubiquitous protein-folding and protein-interaction domains in which two or more α-helical chains come together to form bundles. Through a combination of bioinformatics analysis of many thousands of natural coiled-coil sequences and structures, plus empirical protein engineering and design studies, there is now a deep understanding of the sequence-to-structure relationships for this class of protein architecture. This has led to considerable success in rational design and what might be termed in biro de novo design of simple coiled coils, which include homo- and hetero-meric parallel dimers, trimers and tetramers...
2017: Sub-cellular Biochemistry
https://www.readbyqxmd.com/read/28101344/evaluation-of-pharmacological-relaxation-effect-of-the-natural-product-naringin-on-in-vitro-cultured-airway-smooth-muscle-cells-and-in-vivo-ovalbumin-induced-asthma-balb-c-mice
#15
Yue Wang, Yun Lu, Mingzhi Luo, Xiaohao Shi, Yan Pan, Huilong Zeng, Linhong Deng
Asthma has become a common chronic respiratory disease worldwide and its prevalence is predicted to continue increasing in the next decade, particularly in developing countries. A key component in asthma therapy is to alleviate the excessive bronchial airway narrowing ultimately due to airway smooth muscle contraction, which is often facilitated by a smooth muscle relaxant, such as the β2-adrenergic agonists. Recently, bitter taste receptor (TAS2R) agonists, including saccharin and chloroquine, have been found to potently relax the airway smooth muscle cells (ASMCs) via intracellular Ca(2+) signaling...
December 2016: Biomedical Reports
https://www.readbyqxmd.com/read/28100711/effects-of-structural-complexity-on-within-canopy-light-environments-and-leaf-traits-in-a-northern-mixed-deciduous-forest
#16
Alexander T Fotis, Peter S Curtis
Canopy structure influences forest productivity through its effects on the distribution of radiation and the light-induced changes in leaf physiological traits. Due to the difficulty of accessing and measuring forest canopies, few field-based studies have quantitatively linked these divergent scales of canopy functioning. The objective of our study was to investigate how canopy structure affects light profiles within a forest canopy and whether leaves of mature trees adjust morphologically and biochemically to the light environments characteristic of canopies with different structural complexity...
January 18, 2017: Tree Physiology
https://www.readbyqxmd.com/read/28100622/glycosylation-of-the-ha-protein-of-h5n1-virus-increases-its-virulence-in-mice-by-exacerbating-the-host-immune-response
#17
Dongming Zhao, Libin Liang, Shuai Wang, Tomomi Nakao, Yanbing Li, Liling Liu, Yuntao Guan, Satoshi Fukuyama, Zhigao Bu, Yoshihiro Kawaoka, Hualan Chen
: The highly pathogenic avian influenza (HPAI) H5N1 viruses continue to circulate in nature and threaten public health. Although several viral determinants and host factors that influence the virulence of HPAI H5N1 viruses in mammals have been identified, the detailed molecular mechanism remains poorly defined and requires further clarification. In our previous studies, we characterized two naturally isolated HPAI H5N1 viruses that had similar viral genomes but differed substantially in their lethality in mice...
January 18, 2017: Journal of Virology
https://www.readbyqxmd.com/read/28100450/a-2-oxoglutarate-dependent-dioxygenase-mediates-the-biosynthesis-of-glucoraphasatin-in-radish
#18
Tomohiro Kakizaki, Hiroyasu Kitashiba, Zhongwei Zou, Feng Li, Nobuko Fukino, Takayoshi Ohara, Takeshi Nishio, Masahiko Ishida
Glucosinolates (GSLs) are secondary metabolites whose degradation products confer intrinsic flavors and aromas to Brassicaceae vegetables. Several structures of GSLs are known in the Brassicaceae, and the biosynthetic pathway and regulatory networks have been elucidated in Arabidopsis thaliana. GSLs are precursors of chemical defense substances against herbivorous pests. Specific GSLs can act as feeding blockers or stimulants, depending on the pest species. Natural selection has led to diversity in the GSL compositions even within individual species...
January 18, 2017: Plant Physiology
https://www.readbyqxmd.com/read/28100218/antiviral-effect-of-compounds-derived-from-the-seeds-of-mammea-americana-and-tabernaemontana-cymosa-on-dengue-and-chikungunya-virus-infections
#19
Cecilia Gómez-Calderón, Carol Mesa-Castro, Sara Robledo, Sergio Gómez, Santiago Bolivar-Avila, Fredyc Diaz-Castillo, Marlen Martínez-Gutierrez
BACKGROUND: The transmission of Dengue virus (DENV) and Chikungunya virus (CHIKV) has increased worldwide, due in part to the lack of a specific antiviral treatment. For this reason, the search for compounds with antiviral potential, either as licensed drugs or in natural products, is a research priority. The objective of this study was to identify some of the compounds that are present in Mammea americana (M. americana) and Tabernaemontana cymosa (T. cymosa) plants and, subsequently, to evaluate their cytotoxicity in VERO cells and their potential antiviral effects on DENV and CHIKV infections in those same cells...
January 18, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28099885/oestrus-synchronisation-and-superovulation-alter-the-cervicovaginal-mucus-proteome-of-the-ewe
#20
Jessie W Maddison, Jessica P Rickard, Naomi C Bernecic, Guillaume Tsikis, Clement Soleilhavoup, Valerie Labas, Lucie Combes-Soia, Gregoire Harichaux, Xavier Druart, Tamara Leahy, Simon P de Graaf
: Although essential for artificial insemination (AI) and MOET (multiple ovulation and embryo transfer), oestrus synchronisation and superovulation are associated with increased female reproductive tract mucus production and altered sperm transport. The effects of such breeding practices on the ovine cervicovaginal (CV) mucus proteome have not been detailed. The aim of this study was to qualitatively and quantitatively investigate the Merino CV mucus proteome in naturally cycling (NAT) ewes at oestrus and mid-luteal phase, and quantitatively compare CV oestrus mucus proteomes of NAT, progesterone synchronised (P4) and superovulated (SOV) ewes...
January 15, 2017: Journal of Proteomics
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