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https://www.readbyqxmd.com/read/28102681/cascade-c-h-annulation-of-aldoximes-with-alkynes-using-o2-as-the-sole-oxidant-one-pot-access-to-multisubstituted-protoberberine-skeletons
#1
Junbin Tang, Shiqing Li, Zheng Liu, Yinsong Zhao, Zhijie She, Vilas D Kadam, Ge Gao, Jingbo Lan, Jingsong You
A cascade double C-H annulation of aldoximes with alkynes to produce benz[a]acridizinium salts is developed by using a simple catalytic system of [Cp*Rh(OAc)2]2 in the presence of Zn(OTf)2 with oxygen as the sole oxidant. In addition, the challenging C-H annulation of aldoximes with alkynes, especially arylalkynes, to synthesize 1H-isoquinolines is also achieved under slightly modified conditions. This protocol provides an efficient one-pot access to multisubstituted dehydroberberinium skeletons from simple starting materials, which can be easily transformed into berberinium and tetrahydroberberine skeletons by controlled hydrogenation...
January 19, 2017: Organic Letters
https://www.readbyqxmd.com/read/28102673/total-synthesis-of-%C3%A2-berkeleyone-a
#2
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/28102101/thyroid-in-pregnancy-from-physiology-to-screening
#3
Drahomira Springer, Jan Jiskra, Zdenka Limanova, Tomas Zima, Eliska Potlukova
Thyroid hormones are crucial for the growth and maturation of many target tissues, especially the brain and skeleton. During critical periods in the first trimester of pregnancy, maternal thyroxine is essential for fetal development as it supplies thyroid hormone-dependent tissues. The ontogeny of mature thyroid function involves organogenesis, and maturation of the hypothalamus, pituitary and the thyroid gland; and it is almost complete by the 12th-14th gestational week. In case of maternal hypothyroidism, substitution with levothyroxine must be started in early pregnancy...
January 19, 2017: Critical Reviews in Clinical Laboratory Sciences
https://www.readbyqxmd.com/read/28101749/twenty-seven-years-of-cerebral-pyruvate-recycling
#4
Sebastián Cerdán
Cerebral pyruvate recycling is a metabolic pathway deriving carbon skeletons and reducing equivalents from mitochondrial oxaloacetate and malate, to the synthesis of mitochondrial and cytosolic pyruvate, lactate and alanine. The pathway allows both, to provide the tricarboxylic acid cycle with pyruvate molecules produced from alternative substrates to glucose and, to generate reducing equivalents necessary for the operation of NADPH requiring processes. At the cellular level, pyruvate recycling involves the activity of malic enzyme, or the combined activities of phosphoenolpyruvate carboxykinase and pyruvate kinase, as well as of those transporters of the inner mitochondrial membrane exchanging the corresponding intermediates...
January 18, 2017: Neurochemical Research
https://www.readbyqxmd.com/read/28100813/coral-calcifying-fluid-ph-is-modulated-by-seawater-carbonate-chemistry-not-solely-seawater-ph
#5
S Comeau, E Tambutté, R C Carpenter, P J Edmunds, N R Evensen, D Allemand, C Ferrier-Pagès, S Tambutté, A A Venn
Reef coral calcification depends on regulation of pH in the internal calcifying fluid (CF) in which the coral skeleton forms. However, little is known about calcifying fluid pH (pHCF) regulation, despite its importance in determining the response of corals to ocean acidification. Here, we investigate pHCF in the coral Stylophora pistillata in seawater maintained at constant pH with manipulated carbonate chemistry to alter dissolved inorganic carbon (DIC) concentration, and therefore total alkalinity (AT). We also investigate the intracellular pH of calcifying cells, photosynthesis, respiration and calcification rates under the same conditions...
January 25, 2017: Proceedings. Biological Sciences
https://www.readbyqxmd.com/read/28099816/new-treatment-options-and-emerging-drugs-for-axial-spondyloarthritis-biological-and-targeted-synthetic-agents
#6
Eric Toussirot
Ankylosing spondylitis (AS) and axial spondyloarthritis (ax SpA) are chronic inflammatory diseases mainly involving the axial skeleton. Pharmacological treatments for AS and ax SpA usually include local glucocorticoid injections, NSAIDs and anti-TNFa agents. Since around 30% to 40% of patients are non responders or intolerant to anti-TNFa agents, we need new therapeutic options for AS and ax SpA. Areas covered: This review describes the new biological agents that can be used or are in development for AS or ax SpA as well as emerging synthetic targeted drugs...
January 18, 2017: Expert Opinion on Pharmacotherapy
https://www.readbyqxmd.com/read/28099128/bone-health-assessment-of-food-allergic-children-on-restrictive-diets-a-practical-guide
#7
Artemis E Doulgeraki, Emmanouel M Manousakis, Nikolaos G Papadopoulos
BACKGROUND: Food allergy in childhood is on the rise globally and is managed with avoidance diets; recent case reports of food allergic children with nutritional rickets in the literature highlight the importance of close monitoring of bone health in this population. METHODS: There is no consensus as yet with regard to bone health evaluation in food allergic children; therefore, extensive literature search was performed and the existing evidence is presented, along with a relevant algorithm...
January 18, 2017: Journal of Pediatric Endocrinology & Metabolism: JPEM
https://www.readbyqxmd.com/read/28098317/a-novel-withanolide-with-an-unprecedented-carbon-skeleton-from-physalis-angulata
#8
Cheng-Peng Sun, Andrei G Kutateladze, Feng Zhao, Li-Xia Chen, Feng Qiu
A novel withanolide, aromaphysalin A (1), possessing an exceptional C(11)-C(15) bond and an unprecedented 4,9-cyclized aromatic ring (ring A), is isolated from stems and leaves of Physalis angulata L. Its structure was determined by a combination of HRESIMS, 2D NMR spectra, and theoretical calculations. Compound 1 exhibited inhibitory activity on NO production with an IC50 value of 51.64 μM. A plausible biosynthetic pathway for 1 is also discussed.
January 18, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28098180/an-aposymbiotic-primary-coral-polyp-counteracts-acidification-by-active-ph-regulation
#9
Yoshikazu Ohno, Akira Iguchi, Chuya Shinzato, Mayuri Inoue, Atsushi Suzuki, Kazuhiko Sakai, Takashi Nakamura
Corals build their skeletons using extracellular calcifying fluid located in the tissue-skeleton interface. However, the mechanism by which corals control the transport of calcium and other ions from seawater and the mechanism of constant alkalization of calcifying fluid are largely unknown. To address these questions, we performed direct pH imaging at calcification sites (subcalicoblastic medium, SCM) to visualize active pH upregulation in live aposymbiotic primary coral polyps treated with HCl-acidified seawater...
January 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28097623/toward-a-functional-definition-of-ankyloglossia-validating-current-grading-scales-for-lingual-frenulum-length-and-tongue-mobility-in-1052-subjects
#10
Audrey Yoon, Soroush Zaghi, Rachel Weitzman, Sandy Ha, Clarice S Law, Christian Guilleminault, Stanley Y C Liu
PURPOSE: Alterations of the lingual frenulum may contribute to oromyofacial dysfunction, speech and swallowing impediments, underdevelopment of the maxillofacial skeleton, and even predispose to sleep breathing disorder. This study aims to assess the utility of existing instruments for evaluation of restricted tongue mobility, describe normal and abnormal ranges of tongue mobility, and provide evidence in support of a reliable and efficient measure of tongue mobility. METHODS: A prospective cohort study of 1052 consecutive patients was evaluated during a 3-month period...
January 17, 2017: Sleep & Breathing, Schlaf & Atmung
https://www.readbyqxmd.com/read/28097045/homeopathy-a-safe-much-less-expensive-non-invasive-viable-alternative-for-the-treatment-of-patients-suffering-from-loss-of-lumbar-lordosis
#11
Saiful Haque, Debarsi Das, Saugato Bhattacharya, Tathagato Sarkar, Anisur Rahman Khuda-Bukhsh
OBJECTIVES: Loss of lumbar lordosis causing pain and curvature of the vertebral skeleton to one side is a relatively uncommon disease. To our knowledge, successful treatment of loss of lumbar lordosis with any potentized homeopathic drug diluted above Avogadro's limit (that is, above a potency of 12C) has not been documented so far. In this communication, we intend to document a relatively rare case of loss of lumbar lordosis with osteophytic lippings, disc desiccation, and protrusion, causing a narrowing of secondary spinal canal and a bilateral neural foramina, leading to vertebral column curvature with acute pain in an adolescent boy...
December 2016: Journal of Pharmacopuncture
https://www.readbyqxmd.com/read/28096449/specific-glucoside-transporters-influence-septal-structure-and-function-in-the-filamentous-heterocyst-forming-cyanobacterium-anabaena-sp-strain-pcc-7120
#12
Mercedes Nieves-Morión, Sigal Lechno-Yossef, Rocío López-Igual, José E Frías, Vicente Mariscal, Dennis J Nürnberg, Conrad W Mullineaux, C Peter Wolk, Enrique Flores
: When deprived of combined nitrogen, some filamentous cyanobacteria contain two cell types: vegetative cells that fix CO2 through oxygenic photosynthesis and heterocysts that are specialized in N2 fixation. In the diazotrophic filament, the vegetative cells provide the heterocysts with reduced carbon (mainly in the form of sucrose) and heterocysts provide the vegetative cells with combined nitrogen. Septal junctions traverse peptidoglycan through structures known as nanopores, and appear to mediate intercellular molecular transfer that can be traced with fluorescent markers, including the sucrose analog esculin (a coumarin glucoside) that is incorporated into the cells...
January 17, 2017: Journal of Bacteriology
https://www.readbyqxmd.com/read/28095853/crispri-mediated-metabolic-engineering-of-e-coli-for-o-methylated-anthocyanin-production
#13
Brady F Cress, Quentin D Leitz, Daniel C Kim, Teresita D Amore, Jon Y Suzuki, Robert J Linhardt, Mattheos A G Koffas
BACKGROUND: Anthocyanins are a class of brightly colored, glycosylated flavonoid pigments that imbue their flower and fruit host tissues with hues of predominantly red, orange, purple, and blue. Although all anthocyanins exhibit pH-responsive photochemical changes, distinct structural decorations on the core anthocyanin skeleton also cause dramatic color shifts, in addition to improved stabilities and unique pharmacological properties. In this work, we report for the first time the extension of the reconstituted plant anthocyanin pathway from (+)-catechin to O-methylated anthocyanins in a microbial production system, an effort which requires simultaneous co-option of the endogenous metabolites UDP-glucose and S-adenosyl-L-methionine (SAM or AdoMet)...
January 17, 2017: Microbial Cell Factories
https://www.readbyqxmd.com/read/28094530/unexpected-o-h-insertion-of-rhodium-azavinylcarbenes-with-n-acylhydrazones-divergent-synthesis-of-3-6-disubstituted-and-3-5-6-trisubstituted-1-2-4-triazines
#14
Jiang Meng, Min Wen, Shiwei Zhang, Peiwen Pan, Xingxin Yu, Wei-Ping Deng
A practical and efficient method for divergent synthesis of 3,6-disubstituted- and 3,5,6-trisubstituted-1,2,4-triazines via unexpected rhodium-catalyzed O-H insertion/rearrangement/conditions-controlled intramolecular cyclization and oxidation reaction under mild conditions has been developed. Notably, it is the first example for the synthesis of 1,2,4-triazines with different substituted-patterns via a common intermediate with excellent chemoselectivities by the reaction of N-acylhydrazones as aze-[3C] or [4C] synthons with N-sulfonyl-1,2,3-triazoles as aze-[2C] synthons...
January 17, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28094431/chordoma-immunohistochemical-analysis-of-brachury
#15
İbrahim Sun, Mustafa Güdük, Bülent Güçyetmez, Özlem Yapicier, M Necmettin Pamir
AIM: Chordomas are rare, slow growing but locally aggressive malignancies of the axial skeleton. Skull base chordomas, due to their intricate anatomical localization pose significant challenges to managing physician. In classical and chondroid chordomas the disease course cannot be reliably determined using only morphological criteria. Brachyury (T Gene) was shown to play a central role in chordoma pathogenesis and several studies have also shown that this gene also caries potential as a prognostic biomarker...
December 12, 2016: Turkish Neurosurgery
https://www.readbyqxmd.com/read/28094004/the-vertebrae-and-ribs-of-homo-naledi
#16
Scott A Williams, Daniel García-Martínez, Markus Bastir, Marc R Meyer, Shahed Nalla, John Hawks, Peter Schmid, Steven E Churchill, Lee R Berger
Hominin evolution featured shifts from a trunk shape suitable for climbing and housing a large gut to a trunk adapted to bipedalism and higher quality diets. Our knowledge regarding the tempo, mode, and context in which these derived traits evolved has been limited, based largely on a small-bodied Australopithecus partial skeleton (A.L. 288-1; "Lucy") and a juvenile Homo erectus skeleton (KNM-WT 15000; "Turkana Boy"). Two recent discoveries, of a large-bodied Australopithecus afarensis (KSD-VP-1/1) and two Australopithecus sediba partial skeletons (MH1 and MH2), have added to our understanding of thorax evolution; however, little is known about thorax morphology in early Homo...
January 13, 2017: Journal of Human Evolution
https://www.readbyqxmd.com/read/28089586/natural-uranium-impairs-the-differentiation-and-the-resorbing-function-of-osteoclasts
#17
Tatiana Gritsaenko, Valérie Pierrefite-Carle, Thomas Lorivel, Véronique Breuil, Georges F Carle, Sabine Santucci-Darmanin
BACKGROUND: Uranium is a naturally occurring radionuclide ubiquitously present in the environment. The skeleton is the main site of uranium long-term accumulation. While it has been shown that natural uranium is able to perturb bone metabolism through its chemical toxicity, its impact on bone resorption by osteoclasts has been poorly explored. Here, we examined for the first time in vitro effects of natural uranium on osteoclasts. METHODS: The effects of uranium on the RAW 264...
January 9, 2017: Biochimica et Biophysica Acta
https://www.readbyqxmd.com/read/28089322/a-central-giant-cell-granuloma-in-posterior-part-of-maxilla-a-case-report
#18
Priyanka Garg, Jinendra Jain, Nayana De, Kushal Chatterjee
INTRODUCTION: Central Giant Cell Granuloma (CGCG) is an intraosseous lesion consisting of cellular fibrous tissue that contains multiple foci of hemorrhage, aggregations of multinucleated giant cells and occasionally trabeculae of woven bone1. PRESENTATION OF CASE: we are presenting a case of Central Giant Cell Granuloma on Maxilla. Extra oral examination revealed a diffuse swelling on the left side of face causing slight obliteration of nasio - nasolabial labial fold resulting in facial asymmetry & Intraoral examination shows a purple expansile mass in the region of upper left 26, 27 and 28 edentulous areas...
November 17, 2016: International Journal of Surgery Case Reports
https://www.readbyqxmd.com/read/28087899/increasing-dietary-nitrate-has-no-effect-on-cancellous-bone-loss-or-fecal-microbiome-in-ovariectomized-rats
#19
Melissa N Conley, Cooper Roberts, Thomas J Sharpton, Urszula T Iwaniec, Norman Hord
Studies suggest diets rich in fruit and vegetables reduce bone loss, although the specific compounds responsible are unknown. Substrates for endogenous nitric oxide (NO) production, including organic nitrates and dietary nitrate, may support NO production in age-related conditions, including osteoporosis. We investigated the capability of dietary nitrate to improve NO bioavailability, reduce bone turnover and loss. Six-month-old Sprague Dawley rats [30 ovariectomized (OVX) and 10 sham-operated (sham)] were randomized into 3 groups: (1) vehicle (water) control, (2) low-dose nitrate (LDN, 0...
January 13, 2017: Molecular Nutrition & Food Research
https://www.readbyqxmd.com/read/28081580/biosynthetic-studies-on-acetosellin-and-structure-elucidation-of-a-new-acetosellin-derivative
#20
Peter Hufendiek, Simon Stephan Martin Stölben, Stefan Kehraus, Nicole Merten, Henrik Harms, Max Crüsemann, Idris Arslan, Michael Gütschow, Tanja Schneider, Gabriele Maria König
Natural products from fungi, especially Ascomycota, play a major role in therapy and drug discovery. Fungal strains originating from marine habitats offer a new avenue for finding unusual molecular skeletons. Here, the marine-derived fungus Epicoccum nigrum (strain 749) was found to produce the azaphilonoid compounds acetosellin and 5',6'-dihydroxyacetosellin. The latter is a new natural product. The biosynthesis of these polyketide-type compounds is intriguing, since two polyketide chains are assembled to the final product...
January 12, 2017: Planta Medica
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