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https://www.readbyqxmd.com/read/29793144/structural-confirmation-and-spectroscopic-study-of-a-biomolecule-norepinephrine
#1
T Yadav, V Mukherjee
The present work deals with the conformational and vibrational spectroscopic study of an important bio-molecule named norepinephrine in gas phase. The FTIR and FTRaman spectrum of norepinephrine in amorphous form were recorded in wavenumber range 4000-400 cm-1 and 4000-50 cm-1 respectively. We have investigated twenty-seven stable conformational structures of norepinephrine molecule. All the calculations have been done using Density Functional Theory with exchange functional B3LYP incorporated with the 6-31++G(d, p) basis set...
May 21, 2018: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/29792856/comparison-of-the-3-d-patterns-of-the-parasympathetic-nervous-system-in-the-lung-at-late-developmental-stages-between-mouse-and-chicken
#2
Tadayoshi Watanabe, Ryo Nakamura, Yuta Takase, Etsuo A Susaki, Hiroki R Ueda, Ryosuke Tadokoro, Yoshiko Takahashi
Although the basic schema of the body plan is similar among different species of amniotes (mammals, birds, and reptiles), the lung is an exception. Here, anatomy and physiology are considerably different, particularly between mammals and birds. In mammals, inhaled and exhaled airs mix in the airways, whereas in birds the inspired air flows unidirectionally without mixing with the expired air. This bird-specific respiration system is enabled by the complex tubular structures called parabronchi where gas exchange takes place, and also by the bellow-like air sacs appended to the main part of the lung...
May 21, 2018: Developmental Biology
https://www.readbyqxmd.com/read/29792806/fate-of-fluorescence-labels-their-adsorption-and-desorption-kinetics-to-silver-nanoparticles
#3
Claudia Kästner, Linda Böhmert, Albert Braeuning, Alfonso Lampen, Andreas F Thünemann
Silver nanoparticles are among the most widely used und produced nanoparticles. Due to their frequent application in consumer products, the assessment of their toxicological potential has seen a renewed importance. A major difficulty is the traceability of nanoparticles in in vitro and in vivo experiments. Even if the particles are labeled, for example by a fluorescent marker, the dynamic exchange of ligands often prohibits their spatial localization. Our study provides an insight into the adsorption and desorption kinetics of two different fluorescent labels on silver nanoparticles with a core radius of 3 nm by dynamic light scattering (DLS), small-angle X-ray scattering (SAXS) and fluorescence spectroscopy...
May 24, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/29792704/double-hydrogen-atom-exchange-reactions-of-hx-x-f-cl-br-i-with-ho2
#4
Rex T Skodje, Jonathan R Church
A novel double hydrogen atom exchange process, HX+H'O2H'X+HO2 for the halogen series X=F, Cl, Br, and I, is identified using theoretical methods. These concerted reactions are mediated through a stabilized five-member planar ring transition state structure. The transition state barrier for the double exchange process is found to be significantly lower than that for the abstraction reaction of a single hydrogen atom, . Density functional theory employing the M11 exchange functional is used to compute parameters of the potential energy surface and the rate coefficients are obtained using transition state theory with small curvature tunneling...
May 24, 2018: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/29792674/partial-intrinsic-disorder-governs-the-dengue-capsid-protein-conformational-ensemble
#5
Priscilla L S Boon, Wuan Geok Saw, Xin Xiang Lim, Palur Venkata Raghuvamsi, Roland G Huber, Jan K Marzinek, Daniel A Holdbrook, Ganesh S Anand, Gerhard Grüber, Peter J Bond
The 11 kDa, positively charged dengue capsid protein (C protein) exists stably as a homodimer and co-localizes with the viral genome within mature viral particles. Its core is composed of four alpha helices encompassing a small hydrophobic patch that may interact with lipids, but approximately 20% of the protein at the N-terminus is intrinsically disordered, making it challenging to elucidate its conformational landscape. Here, we combine small-angle X-ray scattering (SAXS), amide hydrogen-deuterium exchange mass spectrometry (HDXMS), and atomic-resolution molecular dynamics (MD) simulations to probe the dynamics of dengue C proteins...
May 24, 2018: ACS Chemical Biology
https://www.readbyqxmd.com/read/29792672/biosynthesis-of-lincosamide-antibiotics-reactions-associated-with-degradation-and-detoxification-pathways-play-a-constructive-role
#6
Daozhong Zhang, Zhijun Tang, Wen Liu
Natural products typically are small molecules produced by living organisms. These products possess a wide variety of biological activities and thus have historically played a critical role in medicinal chemistry and chemical biology either as chemotherapeutic agents or as useful tools. Natural products are not synthesized for use by human beings; rather, living organisms produce them in response to various biochemical processes and environmental concerns, both internal and external. These processes/concerns are often dynamic and thus motivate the diversification, optimization, and selection of small molecules in line with changes in biological function...
May 24, 2018: Accounts of Chemical Research
https://www.readbyqxmd.com/read/29792566/clues-to-an-evolutionary-mystery-the-genes-for-t-toxin-enabler-of-the-devastating-1970-southern-corn-leaf-blight-epidemic-are-present-in-ancestral-species-suggesting-an-ancient-origin
#7
Bradford J Condon, Candace E Elliott, Jonathan Gonzalez, Sung-Hwan Yun, Yasunori Akagi, Tyr Wiesner-Hanks, Motoichiro Kodama, Gillian Turgeon
The Southern Corn Leaf Blight epidemic of 1970 devastated fields of T-cytoplasm corn planted in monoculture throughout the eastern US. The epidemic was driven by race T, a previously unseen race of Cochliobolus heterostrophus. A second fungus, Phyllosticta zeae-maydis, with the same biological specificity, appeared coincidentally. Race T produces T-toxin, while P. zeae-maydis produces PM-toxin, both host selective polyketide toxins necessary for supervirulence. Present abundance of genome sequences offers an opportunity to tackle the evolutionary origins of T- and PM- toxin biosynthetic genes, previously thought unique to these species...
May 24, 2018: Molecular Plant-microbe Interactions: MPMI
https://www.readbyqxmd.com/read/29792531/the-expression-of-lysophosphatidic-acid-receptor-5-is-necessary-for-the-regulation-of-intestinal-na-h-exchanger-3-by-lysophosphatidic-acid-in-vivo
#8
Kayte A Jenkin, Peijian He, C Chris Yun
Lysophosphatidic acid (LPA) is a bioactive lipid molecule, which regulates a broad range of pathophysiological processes. Recent studies have demonstrated that LPA modulates electrolyte flux in the intestine and its potential as an anti-diarrheal agent has been suggested. Of six LPA receptors, LPA5 is highly expressed in the intestine. Recent studies by our group have demonstrated activation of Na+ /H+ exchanger 3 (NHE3) by LPA5 . However, much of what has been elucidated was achieved using colonic cell lines that were transfected to express LPA5 ...
May 24, 2018: American Journal of Physiology. Gastrointestinal and Liver Physiology
https://www.readbyqxmd.com/read/29792422/toward-total-synthesis-of-thiolate-protected-metal-nanoclusters
#9
Qiaofeng Yao, Tiankai Chen, Xun Yuan, Jianping Xie
Total synthesis, where desired organic- and/or biomolecules could be produced from simple precursors at atomic precision and with known step-by-step reactions, has prompted centuries-lasting bloom of organic chemistry since its conceptualization in 1828 (Wöhler synthesis of urea). Such expressive science is also highly desirable in nanoscience, since it represents a decisive step toward atom-by-atom customization of nanomaterials for basic and applied research. Although total synthesis chemistry is less established in nanoscience, recent years have witnessed seminal advances and increasing research efforts devoted into this field...
May 24, 2018: Accounts of Chemical Research
https://www.readbyqxmd.com/read/29792414/hybrid-assembly-of-different-sized-supertetrahedral-clusters-into-a-unique-non-interpenetrated-mn-in-s-open-framework-with-large-cavity
#10
Hongxiang Wang, Wei Wang, Dandan Hu, Min Luo, Chaozhuang Xue, Dongsheng Li, Tao Wu
Reported here is a unique crystalline semiconductor open-framework material built from the large-sized supertetrahedral T4 and T5 clusters with the Mn-In-S compositions. The hybrid assembly between T4 and T5 clusters by sharing terminal μ2 -S2- is for the first time observed among the cluster-based chalcogenide open frameworks. Such three-dimensional structure displays non-interpenetrated diamond-type topology with extra-large nonframework volume of 82%. Moreover, ion exchange, CO2 adsorption, as well as photoluminescence properties of the title compound are also investigated...
May 24, 2018: Inorganic Chemistry
https://www.readbyqxmd.com/read/29792349/pulmonary-endothelial-permeability-and-tissue-fluid-balance-depend-on-the-viscosity-of-the-perfusion-solution
#11
Simon C Rowan, Keith D Rochfort, Lucie Piouceau, Philip M Cummins, Malachy O'Rourke, Paul McLoughlin
Fluid filtration in the pulmonary microcirculation depends on the hydrostatic and oncotic pressure gradients across the endothelium, and the selective permeability of the endothelial barrier. Maintaining normal fluid balance depends both on specific properties of the endothelium and of the perfusing blood. Although some of the essential properties of blood needed to prevent excessive fluid leak have been identified and characterised, our understanding of these remains incomplete. The role of perfusate viscosity in maintaining normal fluid exchange has not previously been examined...
May 24, 2018: American Journal of Physiology. Lung Cellular and Molecular Physiology
https://www.readbyqxmd.com/read/29792317/in-situ-reduction-from-uranyl-ion-into-a-tetravalent-uranium-trimer-and-hexamer-featuring-ion-exchange-properties-and-the-alexandrite-effect
#12
Jian Lin, Zenghui Yue, Mark A Silver, Meiying Qie, Xiaomei Wang, Wei Liu, Xiao Lin, Hong-Liang Bao, Lin-Juan Zhang, Shuao Wang, Jian-Qiang Wang
By utilizing zinc amalgam as an in situ reductant and pH regulator, mild hydrothermal reaction between UO2 (CH3 COO)2 ·2H2 O, H2 SO4 , and Cs2 CO3 or between UO2 (CH3 COO)2 ·2H2 O, C2 H4 (SO3 H)2 , and K2 CO3 yielded a novel cesium UIV sulfate trimer Cs4 [U3 O(SO4 )7 ]·2.2H2 O (1) and a new potassium UIV disulfonic hexamer K[U6 O4 (OH)5 (H2 O)5 ][C2 H4 (SO3 )2 ]6 ·6H2 O (2), respectively. Compound 1 features a lamellar structure with a honeycomb lattice, and it represents an unprecedented trimeric UIV cluster composed of purely inorganic moieties...
May 24, 2018: Inorganic Chemistry
https://www.readbyqxmd.com/read/29792026/co-bridged-h-cluster-intermediates-in-the-catalytic-mechanism-of-fefe-hydrogenase-cai
#13
Michael W Ratzloff, Jacob H Artz, David W Mulder, Reuben T Collins, Thomas E Furtak, Paul W King
The [FeFe]-hydrogenases ([FeFe] H2 ases) catalyze reversible H2 activation at the H-cluster, which is composed of a [4Fe-4S]H subsite linked by a cysteine thiolate to a bridged, organometallic [2Fe-2S] ([2Fe]H ) subsite. Profoundly different geometric models of the H-cluster redox states that orchestrate the electron/proton transfer steps of H2 bond activation have been proposed. We have examined this question in the [FeFe] H2 ase I from Clostridium acetobutylicum (CaI) by Fourier-transform infrared (FTIR) spectroscopy with temperature annealing and H/D isotope exchange to identify the relevant redox states and define catalytic transitions...
May 23, 2018: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/29791805/identifying-the-nonradical-mechanism-in-the-peroxymonosulfate-activation-process-singlet-oxygenation-versus-mediated-electron-transfer
#14
Eun-Tae Yun, Jeong Hoon Lee, Jaesung Kim, Hee-Deung Park, Jaesang Lee
Select persulfate activation processes were demonstrated to initiate oxidation not reliant on sulfate radicals, though the underlying mechanism has yet to be identified. This study explored singlet oxygenation and mediated electron transfer as plausible nonradical mechanisms for organic degradation by carbon nanotube (CNT)-activated peroxymonosulfate (PMS). The degradation of furfuryl alcohol (FFA) as a singlet oxygen (1O2) indicator and the kinetic retardation of FFA oxidation in the presence of L-histidine and azide as 1O2 quenchers apparently supported a role of 1O2 in the CNT/PMS system...
May 23, 2018: Environmental Science & Technology
https://www.readbyqxmd.com/read/29791776/polymorphism-in-disease-related-apolipoprotein-c-ii-amyloid-fibrils-a-structural-model-for-rod-like-fibrils
#15
Courtney O Zlatic, Yu Mao, Nevena Todorova, Yee-Foong Mok, Geoffrey J Howlett, Irene Yarovsky, Paul R Gooley, Michael D W Griffin
Human apolipoprotein (apo) C-II is one of several plasma apolipoproteins that form amyloid deposits in vivo and is an independent risk factor for cardiovascular disease. Lipid-free apoC-II readily self-assembles into twisted-ribbon amyloid fibrils but forms straight, rod-like amyloid fibrils in the presence of low concentrations of micellar phospholipids. Charge mutations exerted significantly different effects on rod-like fibril formation compared to their effects on twisted-ribbon fibril formation. For instance, the double mutant K30D, D69K apoC-II readily formed twisted-ribbon fibrils, while the rate of rod-like fibril formation in the presence of micellar phospholipid was negligible...
May 23, 2018: FEBS Journal
https://www.readbyqxmd.com/read/29791637/board-games-gerotechnology-in-nursing-care-practice
#16
Paula Cristina de Andrade Pires Olympio, Neide Aparecida Titonelli Alvim
OBJECTIVE: To create a board game as a form of gerotechnology to promote active and healthy aging. METHOD: This was a qualitative, convergent care study conducted with 32 older adults. Individual interviews, creativity and sensitivity techniques, group discussions, and participant observations guided by Paulo Freire's theoretical framework of problematization were used to produce data. The participants and researchers assessed the entire production process at the end of the study, after the gerotechnology was implemented in the groups...
2018: Revista Brasileira de Enfermagem
https://www.readbyqxmd.com/read/29791487/patients-experiences-of-coping-with-idiopathic-pulmonary-fibrosis-and-their-recommendations-for-its-clinical-management
#17
Sameera Senanayake, Kim Harrison, Michael Lewis, Melitta McNarry, Joanne Hudson
BACKGROUND: Idiopathic Pulmonary Fibrosis (IPF) is a chronic, progressive and life-limiting condition. From a healthcare perspective it is vital to establish effective methods of improving the quality of remaining life in these patients. This requires a detailed understanding of the multiple impacts of an IPF diagnosis on the individual. METHODS: We sought to understand how patients coped with their initial diagnosis, how they live with the disease day-to-day, and their experiences and opinions of the professional support they receive...
2018: PloS One
https://www.readbyqxmd.com/read/29791479/social-object-play-between-captive-bottlenose-and-risso-s-dolphins
#18
Hisako Ikeda, Masayuki Komaba, Kumiko Komaba, Ayaka Matsuya, Akihiro Kawakubo, Fumio Nakahara
Many animal species engage in social object play with movable objects. Two bottlenose dolphins (Tursiops truncatus) and one Risso's dolphin (Grampus griseus) owned by the Kujukushima Aquarium, Japan, occasionally shared and played with an object. Herein, we report social object play between two dolphins exchanging a ball in water. Just before delivery of the ball, one dolphin made an action to request the ball from the dolphin that possessed the ball. This request behavior is also discussed in this report. This study is the first to report two different cetacean species engaging in social object play with one object...
2018: PloS One
https://www.readbyqxmd.com/read/29791459/species-identification-and-connectivity-of-marine-amphipods-in-canada-s-three-oceans
#19
Astrid Tempestini, Søren Rysgaard, France Dufresne
Monitoring the distribution of marine biodiversity is a crucial step to better assess the impacts of global changes. Arctic marine fauna is dominated by amphipods in terms of abundance and biomass. These peracarids are an important marine order of crustaceans but the number of species found in the different Canadian oceans is currently unknown. Furthermore, most species are difficult to identify due to poor taxonomic descriptions and morphological convergence. The aim of this study was to assess the species diversity of marine amphipods in the three Canadian oceans using DNA barcoding...
2018: PloS One
https://www.readbyqxmd.com/read/29791436/the-genomic-landscape-at-a-late-stage-of-stickleback-speciation-high-genomic-divergence-interspersed-by-small-localized-regions-of-introgression
#20
Mark Ravinet, Kohta Yoshida, Shuji Shigenobu, Atsushi Toyoda, Asao Fujiyama, Jun Kitano
Speciation is a continuous process and analysis of species pairs at different stages of divergence provides insight into how it unfolds. Previous genomic studies on young species pairs have revealed peaks of divergence and heterogeneous genomic differentiation. Yet less known is how localised peaks of differentiation progress to genome-wide divergence during the later stages of speciation in the presence of persistent gene flow. Spanning the speciation continuum, stickleback species pairs are ideal for investigating how genomic divergence builds up during speciation...
May 23, 2018: PLoS Genetics
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