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Tatiana Y Gorpenchenko, Valeria P Grigorchuk, Dmitry V Bulgakov, Galina K Tchernoded, Victor P Bulgakov
Alkaloids attract great attention due to their valuable therapeutic properties. Stepharine, an aporphine alkaloid of Stephania glabra plants, exhibits anti-aging, anti-hypertensive, and anti-viral effects. The distribution of aporphine alkaloids in cell cultures, as well as whole plants is unknown, which hampers the development of bioengineering strategies toward enhancing their production. The spatial distribution of stepharine in cell culture models, plantlets, and mature micropropagated plants was investigated at the cellular and organ levels...
February 13, 2019: International Journal of Molecular Sciences
Elodie Chevallot-Beroux, Ayuk M Ako, Wolfgang Schmitt, Brendan Twamley, Joseph Moran, Boudon Corinne, Laurent Ruhlmann, Samir Mameri
We report the synthesis and structural characterisation of new Mn19 and Mn18M analogues, [MnIII12MnII7(μ4-O)8(μ3-OCH3)2(μ3-Br)6(HLMe)12(MeOH)6]Br2 (2) and [MnIII12MnII6Sr(μ4-O8(μ3-Cl)8(HLMe)12(MeCN)6]Cl2 cluster (3), where H3LMe is 2,6-bis(hydroxymethyl)-p-cresol. The electrochemistry of 2 and 3 has been investigated and their activity as catalysts in the oxidation of benzyl alcohol has been evaluated. Selective oxidation of benzyl alcohol to benzaldehyde by O2 was achieved using 1 mol% of catalyst with conversions of 74% (2) and 60% (3) at 140 °C using TEMPO as a co-catalyst...
February 19, 2019: Dalton Transactions: An International Journal of Inorganic Chemistry
Patrick T Rohner, Jeannine Roy, Martin A Schäfer, Wolf U Blanckenhorn, David Berger
Although genetic and plastic responses are sometimes considered as unrelated processes, their phenotypic effects may often align because genetic adaptation is expected to mirror phenotypic plasticity if adaptive, but run counter to it when maladaptive. The magnitude and direction of this alignment has further consequences for both the tempo and mode of adaptation. To better understand the interplay between phenotypic plasticity and genetic change in mediating adaptive phenotypic variation to climate variability, we here quantified genetic latitudinal variation and thermal plasticity in wing loading and wing shape in two closely related and widespread sepsid flies...
February 18, 2019: Journal of Evolutionary Biology
J Igea, A J Tanentzap
Why is species diversity so unevenly distributed across different regions on Earth? Regional differences in biodiversity may stem from differences in rates of speciation and dispersal and colonization times, but these hypotheses have rarely been tested simultaneously at a global scale. Our study reveals the macroevolutionary routes that have generated hotspots of mammal and bird biodiversity by analyzing the tempo and mode of diversification and dispersal within major biogeographic realms. Hotspots in tropical realms had higher rates of speciation, whereas those in temperate realms received more immigrant species from their surrounding regions...
February 2019: Science Advances
Ragnhild Aaen, Fredrik Wernersson Brodin, Sébastien Simon, Ellinor Bævre Heggset, Kristin Syverud
Pickering o/w emulsions prepared with 40 wt % rapeseed oil were stabilized with the use of low charged enzymatically treated cellulose nanofibrils (CNFs) and highly charged 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized CNFs. The emulsion-forming abilities and storage stability of the two qualities were tested in the presence of NaCl and acetic acid, at concentrations relevant to food applications. Food emulsions may be an important future application area for CNFs due to their availability and excellent viscosifying abilities...
February 14, 2019: Nanomaterials
Stephen P Becker, Jeffery N Epstein, Leanne Tamm, Alina A Tilford, Clair M Tischner, Paul A Isaacson, John O Simon, Dean W Beebe
OBJECTIVE: Although poor sleep is often reported in adolescents with attention-deficit/hyperactivity disorder (ADHD), prior studies have been correlational. This study investigated whether sleep duration is causally linked to sleepiness, inattention, and behavioral functioning in adolescents with ADHD. METHOD: Seventy-two adolescents (ages 14-17 years) entered a three-week sleep protocol using an experimental crossover design. The protocol included a phase stabilization week, followed in randomized counterbalanced order by 1 week of sleep restriction (6...
November 1, 2018: Journal of the American Academy of Child and Adolescent Psychiatry
Salvador Hernández-Martínez, Víctor Cardoso-Jaime, Marcela Nouzova, Veronika Michalkova, Cesar E Ramirez, Francisco Fernandez-Lima, Fernando G Noriega
Anophelinae mosquitoes are vectors of human malaria, a disease that infects hundreds of millions of people and causes almost 600,000 fatalities annually. Despite their medical importance, laboratory studies on key aspects of Anophelinae reproductive biology have been limited, and in particular, relatively little is known about the role of juvenile hormone (JH) in the control of female reproduction. The study presented here attempts to fill a gap of knowledge in our understanding of the JH control of ovarian development in female Anophelinae mosquitoes, using Anopheles albimanus as a model...
February 14, 2019: Scientific Reports
Jiao-Xia Zou, Yi Jiang, Shuai Lei, Gao-Feng Yin, Xiao-Ling Hu, Quan-Yi Zhao, Zhen Wang
Here, we present an unprecedented pathway to α-sulfenylated carbonyl compounds from commercially available thiols and universally employed TEMPO and its analogues, which act as C3 synthons through skeletal rearrangement under simple and metal-free conditions. Mechanism studies suggest that this reaction involves a consecutive radical oxidation and cation coupling process. TEMPO analogues and thiols serve as oxidants and reductive reagents, respectively, along the radical process, while in the coupling process, the former ones afford C3 synthons to couple with related sulfur sources...
February 13, 2019: Organic & Biomolecular Chemistry
Aggie J Yellow Horse, Alexis R Santos-Lozada
OBJECTIVES: We investigated the patterns of foreign-born Hispanic health convergence to U.S.-born Hispanics using an allostatic load index, a subjective biological risk health profile, and we explored whether the health convergence patterns differ by sex. METHODS: The analytic sample consisted of 3,347 Hispanics from the pooled 2005-2010 National Health and Nutrition Examination Survey. We used negative binomial regression models to investigate the association between duration in the United States and the allostatic load index, while controlling for potential covariates...
February 9, 2019: Women's Health Issues: Official Publication of the Jacobs Institute of Women's Health
Marie E Edwards, Jaime D Blais, Frank S Czerwiec, Bradley J Erickson, Vicente E Torres, Timothy L Kline
Background: The ability of unstandardized methods to track kidney growth in clinical trials for autosomal dominant polycystic kidney disease (ADPKD) has not been critically evaluated. Methods: The Tolvaptan Efficacy and Safety Management of ADPKD and its Outcomes (TEMPO) 3:4 study involved baseline and annual magnetic resonance follow-up imaging yearly for 3 years. Total kidney volume (TKV) measurements were performed on these four time points in addition to the baseline imaging in TEMPO 4:4, initially by Perceptive Informatics (Waltham, MA, USA) using planimetry (original dataset) and for this study by the Mayo Translational PKD Center using semiautomated and complementary automated methods (sequential dataset)...
February 2019: Clinical Kidney Journal
Wenyang Xu, Binbin Zhang Molino, Fang Cheng, Paul J Molino, Zhilian Yue, Dandan Su, Xiaoju Wang, Stefan M Willför, Chunlin Xu, Gordon G Wallace
Cellulose nanofibrils (CNFs) in the form of hydrogels stand out as a platform biomaterial in bioink formulation for 3D printing because of their low cytotoxicity and structural similarity to extracellular matrices. In the present study, 3D scaffolds were successfully printed with low-concentration inks formulated by 1 w/v % 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) -oxidized CNF with less than 1 w/v % gelatin methacrylate (GelMA). Quartz crystal microbalance with dissipation monitoring (QCM-D) measurements showed strong interaction between the two biopolymers...
February 11, 2019: ACS Applied Materials & Interfaces
Xiaofang Lei, Yuanyuan Wang, Erkang Fan, Zhihua Sun
Activation of disulfides with N-halogen succinimide in the presence of TEMPO allows insertion reaction by an isocyanide, the product of which can further accept a wide range of nucleophiles for the generation of isothioureas and related molecular moieties. This new procedure overcomes previous methods that accept essentially only aryl amines as the third nucleophilic component. The diverse nucleophiles usable in our new protocol make this approach a general method for de novo synthesis of many S-containing heterocycles...
February 11, 2019: Organic Letters
Shuangqing Fan, Jingsi Qiao, Jiawei Lai, Haicheng Hei, Zhihong Feng, Qiankun Zhang, Daihua Zhang, Sen Wu, Xiaodong Hu, Dong Sun, Wei Ji, Jing Liu
Layered black phosphorus (BP) has been expected to be a promising material for future electronic and optoelectronic applications since its discovery. However, the difficulty in mass fabricating layered air-stable BP severely obstructs its potential industry applications. Here, we report a new BP chemical modification method to implement all-solution based mass production of layered air-stable BP. This method uses the combination of two electron-deficient reagents of 2,2,6,6-tetramethylpiperidinyl-N-oxyl (TEMPO) and triphenylcarbenium tetrafluorobor ([Ph3C]BF4) to accomplish thinning and/or passivation of BP in organic solvent...
February 11, 2019: ACS Applied Materials & Interfaces
Xinpeng Zhang, Sijia Huang, Maciej Podgórski, Xun Han, Mauro Claudino, Christopher N Bowman
We present a thermally initiated thiol-Michael reaction based on initiation via the temperature-dependent thiol-TEMPO oxidation-reduction reaction. In the presence of a thiol, 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO, p K a = 5.5) is reduced to produce a much stronger base, i.e., tetramethylpiperidine (TMP, p K a = 11.4) in a temperature dependent process. This oxidation-reduction process is dramatically accelerated at elevated temperature, which allows for thermally controlled initiation of the base-catalyzed thiol-Michael addition reaction and potentially other base-catalyzed reaction systems...
August 28, 2018: Polymer Chemistry
Ester Camprodon-Rosanas, Jesus Pujol, Gerard Martínez-Vilavella, Laura Blanco-Hinojo, Santiago Medrano-Martorell, Santiago Batlle, Joan Forns, Núria Ribas-Fitó, Montserrat Dolz, Jordi Sunyer
OBJECTIVE: Sluggish cognitive tempo (SCT) is a cluster of symptoms associated with poor function in various domains of major life activities that may comprise a novel attention disorder distinct from attention-deficit/hyperactivity disorder (ADHD). Nevertheless, very little is known about the neural substrate of SCT in children. The present study aimed to examine associations between SCT symptoms and brain structure and function in school-aged children. METHOD: We performed a cross-sectional MRI study in 178 children 8 to 12 years old from primary schools in Barcelona, Spain...
February 2019: Journal of the American Academy of Child and Adolescent Psychiatry
Tamara J Sussman, Jonathan Posner
Attention-deficit/hyperactivity disorder (ADHD) is a heterogeneous disorder encompassing a wide array of clinical presentations, levels of impairment, etiologies, and neurobiological correlates. Despite this well-known heterogeneity, most research into the pathophysiology of ADHD has relied on comparisons between typically developing youth and those with the disorder (or perhaps further stratifying by DSM-defined ADHD subtypes). Although informative, this approach assumes a level of pathophysiologic homogeneity that belies the large and growing body of literature underscoring diverse neurobiological and neuropsychological profiles subsumed under the umbrella of this complex syndrome...
February 2019: Journal of the American Academy of Child and Adolescent Psychiatry
Lingling Liu, Fanbin Kong
Three types of nanocellulose (NC), namely cellulose nano-fibrils (CNF), TEMPO-oxidized CNF and cellulose nanocrystals (CNC), were studied in terms of their effects on in vitro digestion of whey protein isolate (WPI). The behavior of NC itself during digestion was monitored by particle size, confocal microscopy imaging, viscosity, and zeta potential. 1% CNF and 4% CNC significantly retarded free amino nitrogen (FAN) diffusion (23% and 50% respectively) mainly due to high viscosity. 4% CNC also significantly reduced %FAN release during intestinal digestion...
April 15, 2019: Carbohydrate Polymers
Yu-Ju Lin, Jo Anne Shatkin, Fanbin Kong
The mucoadhesive properties of three types of nanocellulose (CNF, CNC, and Tempo-CNF) was investigated in the digestive condition with ex vivo and in vitro assays. In the ex vivo flow-through method, three nanocellulose materials showed different levels of retention on porcine gastric and intestinal mucosal surfaces. Fluorescence microscopy confirmed that retention of CNF could be due to entanglement with the mucosal layer, while retention of Tempo-CNF could be due to instantaneous gelling on the mucosal surface...
April 15, 2019: Carbohydrate Polymers
Hannah M Strobel, Sara J Hays, Kristine N Moody, Michael J Blum, David C Heins
Remarkably few attempts have been made to estimate contemporary effective population size (Ne) for parasitic species, despite the valuable perspectives it can offer on the tempo and pace of parasite evolution as well as coevolutionary dynamics of host-parasite interactions. In this study, we utilized multi-locus microsatellite data to derive single-sample and temporal estimates of contemporary Ne for a cestode parasite (Schistocephalus solidus) as well as three-spined stickleback hosts (Gasterosteus aculeatus) in lakes across Alaska...
February 5, 2019: Parasitology
Tatsuo Manabe, Akihiro Matsumura, Kazuki Yokokawa, Taro Saito, Mai Fujikura, Naotoshi Iwahara, Takashi Matsushita, Syuuichirou Suzuki, Shin Hisahara, Jun Kawamata, Hiromi Suzuki, Miho C Emoto, Hirotada G Fujii, Shun Shimohama
Alzheimer's disease (AD) is one of the most common neurodegenerative diseases responsible for progressive dementia. Deposition of amyloid-β (Aβ) in the brain is the most important pathophysiological hallmark of AD. In addition, recent evidence indicates that reactive oxygen species (ROS) derived from mitochondria contribute to progression of AD pathology. We thus hypothesized that Aβ accumulates and oxidative stress increases in the brain mitochondria of a transgenic mouse model of AD (APdE9). We measured the quantity of Aβ and the activity of the antioxidant enzyme superoxide dismutase (SOD) in brain mitochondrial fractions prepared from APdE9 and wild-type (WT) mice aged 6, 9, 15, and 18 months...
January 28, 2019: Journal of Alzheimer's Disease: JAD
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