The internal resistance of the BLOOD to shear forces. The in vitro measure of whole blood viscosity is of limited clinical utility because it bears little relationship to the actual viscosity within the circulation, but an increase in the viscosity of circulating blood can contribute to morbidity in patients suffering from disorders such as SICKLE CELL ANEMIA and POLYCYTHEMIA.
Rapid, irregular atrial contractions caused by a block of electrical impulse conduction in the right atrium and a reentrant wave front traveling up the inter-atrial septum and down the right atrial free wall or vice versa. Unlike ATRIAL FIBRILLATION which is caused by abnormal impulse generation, typical atrial flutter is caused by abnormal impulse conduction. As in atrial fibrillation, patients with atrial flutter cannot effectively pump blood into the lower chambers of the heart (HEART VENTRICLES).
Abnormal cardiac rhythm that is characterized by rapid, uncoordinated firing of electrical impulses in the upper chambers of the heart (HEART ATRIA). In such case, blood cannot be effectively pumped into the lower chambers of the heart (HEART VENTRICLES). It is caused by abnormal impulse generation.
Quality Indicators, Health Care
Process that is gone through in order for a device to receive approval by a government regulatory agency. This includes any required preclinical or clinical testing, review, submission, and evaluation of the applications and test results, and post-marketing surveillance. It is not restricted to FDA.
Removal of tissue with electrical current delivered via electrodes positioned at the distal end of a catheter. Energy sources are commonly direct current (DC-shock) or alternating current at radiofrequencies (usually 750 kHz). The technique is used most often to ablate the AV junction and/or accessory pathways in order to interrupt AV conduction and produce AV block in the treatment of various tachyarrhythmias.
A province of Canada on the Pacific coast. Its capital is Victoria. The name given in 1858 derives from the Columbia River which was named by the American captain Robert Gray for his ship Columbia which in turn was named for Columbus. (From Webster's New Geographical Dictionary, 1988, p178 & Room, Brewer's Dictionary of Names, 1992, p81-2)
A cardiotonic glycoside obtained mainly from Digitalis lanata; it consists of three sugars and the aglycone DIGOXIGENIN. Digoxin has positive inotropic and negative chronotropic activity. It is used to control ventricular rate in ATRIAL FIBRILLATION and in the management of congestive heart failure with atrial fibrillation. Its use in congestive heart failure and sinus rhythm is less certain. The margin between toxic and therapeutic doses is small. (From Martindale, The Extra Pharmacopoeia, 30th ed, p666)
Increase in dissociation rate constants of cardiotonic steroid-brain (Na+ + K+)-ATPase complexes by reduction of the unsaturated lactone. (1/2)Several cardiotonic steroids have been modified by reduction of the unsaturated lactone and their interactions with the sodium- and potassium-activated ATPase ((Na+ + K+)-ATPase) have been investigated. Reduction of the unsaturated lactone results in a decrease in binding affinity due primarily to an increase in the dissociation rate constant concomitant with a decrease in the activation free energy of dissociation. This decrease in activation free energy is about 2 to 4 kcal, which is approximately equal to the energy of one hydrogen bond. It is suggested that the increase in dissociation rate due to reduction of the unsaturated lactone may make possible the use of these compounds as affinity ligands for purification of the (Na+ + K+)-ATPase or an ouabain-binding fragment. (+info)
Photoaffinity labeling of (Na+K+)-ATPase with [125I]iodoazidocymarin. (2/2)A radioiodinated, photoactive cardiac glycoside derivative, 4'-(3-iodo-4-azidobenzene sulfonyl)cymarin (IAC) was synthesized and used to label (Na+K+)-ATPase in crude membrane fractions. In the dark, IAC inhibited the activity of (Na+K+)-ATPase in electroplax microsomes from Electrophorus electricus with the same I50 as cymarin. [125I]IAC binding, in the presence of Mg2+ and Pi, was specific, of high affinity (KD = 0.4 microM), and reversible (k-1 = 0.11 min-1) at 30 degrees C. At 0 degree C, the complex was stable for at least 3 h, thus permitting washing before photolysis. Analysis of IAC photolabeled electroplax microsomes by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) (7-14%) showed that most of the incorporated radioactivity was associated with the alpha (Mr = 98,000) and beta (Mr = 44,000) subunits of the (Na+K+)-ATPase (ratio of alpha to beta labeling = 2.5). A higher molecular weight peptide (100,000), similar in molecular weight to the brain alpha(+) subunit, and two lower molecular weight peptides (12,000-15,000), which may be proteolipid, were also labeled. Two-dimensional gel electrophoresis (isoelectric focusing then SDS-PAGE, 10%) resolved the beta subunit into 12 labeled peptides ranging in pI from 4.3 to 5.5. When (Na+K+)-ATPase in synaptosomes from monkey brain cortex was photolabeled and analyzed by SDS-PAGE (7-14%), specific labeling of the alpha(+), alpha, and beta subunits could be detected (ratio of alpha(+) plus alpha to beta labeling = 35). The results show that [125I]IAC is a sensitive probe of the cardiac glycoside binding site of (Na+K+)-ATPase and can be used to detect the presence of the alpha(+) subunit in crude membrane fractions from various sources. (+info)
A practical and enantiospecific conversion of d-galactose to a substituted α,β-unsaturated δ-lactone synthon<...
TY - JOUR. T1 - A practical and enantiospecific conversion of d-galactose to a substituted α,β-unsaturated δ-lactone synthon. AU - Stephens, Benjamin E.. AU - Liu, Fei. PY - 2007/12/24. Y1 - 2007/12/24. N2 - A multi-gram synthesis of a substituted α,β-unsaturated δ-lactone synthon, 1, was developed from commercially available d-galactose. The use of a Horner-Wadsworth-Emmons reaction was able to furnish, with Z selectivity, the enone ester that spontaneously lactonised to provide enantiomerically pure 1.. AB - A multi-gram synthesis of a substituted α,β-unsaturated δ-lactone synthon, 1, was developed from commercially available d-galactose. The use of a Horner-Wadsworth-Emmons reaction was able to furnish, with Z selectivity, the enone ester that spontaneously lactonised to provide enantiomerically pure 1.. UR - http://www.scopus.com/inward/record.url?scp=36448957971&partnerID=8YFLogxK. U2 - 10.1016/j.tetlet.2007.10.141. DO - 10.1016/j.tetlet.2007.10.141. M3 - Article. AN - ...
Repositorio da Producao Cientifica e Intelectual da Unicamp: Arylation Of β,γ-unsaturated Lactones By A Heck-matsuda Reaction:...
The palladium catalysed coupling of aryldiazonium salts with β-γ-unsaturated lactones under basic conditions has been investigated. Both (3H)-furanone and α-angelicalactone were evaluated as substrates in the Heck Matsuda reaction but both failed to afford the desired arylated butenolides. Under basic conditions, β-γ-unsaturated lactones generate highly nucleophilic enolates that preferentially undergo azo coupling reactions with arenediazonium salts to afford aryldiazene butenolides. The electronic and steric effect of the substituents on the aryldiazonium salt in the azo coupling reaction is described. Aryldiazene-lactone derivatives were obtained in good yields from a highly facile and straightforward procedure. An aminoisomaleimide was formed from (3H)-furanone and cyclised to the corresponding pyridazinones in modest yield ...
PROCESS FOR PREPARING UNSATURATED LACTONES - SYMRISE GMBH & CO KG
The invention relates to a process for preparing saturated or unsaturated lactones. This process involves reacting a bicyclic compound or a monocyclic compound with hydrogen peroxide in the presence of a first acid having a pKa of 3 or less and a first organic solvent, thereby forming a hydroperoxide. The obtained mixture comprising the hydroperoxide is subsequently metered to a mixture of a second organic solvent and a dissociation-enhancing catalyst, optionally comprising a second organic acid. The invention also pertains to a process of preparing the hydroperoxide.
Browsing Ciências Exatas e Tecnológicas by Author Karak, Milandip
Butenolides are α, -unsaturated lactone and are found in many natural and unnatural products with diverse biological properties. Owing to the prevalence of the substituted butenolides, much effort has been directed towards ...
Synthesis of novel 6,7-dihydro-5h-oxepin-2-one derivatives
In last decades, biologically active natural compound (R)-goniothalamin and its derivatives received great attention from researchers. The reason for this interest is the wide range of biological properties of goniothalamin; including anti-microbial, antiprotozoan, anti-inflammatory, cytotoxic and anti-proliferative activities. The present study sets out the asymmetric large scale synthesis of Î±,Î²- unsaturated lactone derivative (R)-(+)-6-(2-Methylnaphthalen-1-yl)-5,6-dihydro-2Hpyran- 2-one. In recent studies, this linker modified analog of goniothalamin was shown to be cytotoxic against PC-3 (prostate cancer) and MCF-7 (human breast cancer) cell lines with half maximal inhibitory concentration values of 0.13 Î¼M and 2.6 Î¼M, respectively. The preparation of the target compound consists of three steps. First, asymmetric synthesis of homoallylic alcohol using (R)-Tol-BINAP AgF catalyst complex was performed with allyltrimethoysilane. After that, treating the chiral homoallylic alcohol ...
3,3-Dibromo-2-trifluoromethyl acrylic acid ethyl ester: a versatile platform for the stereoselective preparation of...
We herein describe a method for synthetic routes to multi-functionalized-α-trifluoromethyl α,β-unsaturated lactones and trifluoromethyl pyrazolinones. This involves a tandem stereoselective functionalization of 3,3-dibromo-2-trifluoromethyl acrylic acid ethyl ester and intramolecular cyclization reaction to
Isomerization of anacardic acid - University of St Andrews
Practical applications: Unsaturated lactones are structural elements often found in natural products, which have medicinal value. Benzolactones derived from anacardic acid reported in this work have some structural similarity with lactones such as massoia lactone having medicinal value. Therefore with this idea in mind, the unsaturated benzolactones reported in this work will be tested for their anti pathogenic activity. 3-Propylphenol is used in combination with racemic 1-octen-3-ol and p-cresol to prepare a kairomone for tsetse fly traps. Results from this work describe the suitability of anacardic acid for synthesizing 3-propylphenol. The fact that 3-propylphenol can be synthesized from anacardic acid, a component of cashew nut shell liquid is of particular interest since most of the areas affected with tsetse flies are suitable for growing cashew plants. This means the raw materials (CNSL) for synthesis of 3-propylphenol will be obtained from within the same region where the kairomone is to ...
Some Aspects of the Chemistry of Nitro Compounds - Ecole polytechnique
The present brief account relates our discovery of new reactions revolving around the chemistry of the NO2 group. It covers the condensation of MeNO2 with hindered ketones, and the synthesis of pyrroles, triazoles, and enamides. It also describes new transformations of allylic nitro compounds, such as their conversion to allylic sulfones and unsaturated lactones, their sigmatropic rearrangement into allylic nitrites and thence into allylic alcohols, as well as their use in a short synthesis of nitroestrone derivatives. This is followed by an unusual reduction method furnishing unsubstituted amines (RRC?NH) under conditions where these hydrolytically labile species can be captured inter- or intramolecularly. Finally, a mechanistic study of a strange alkyne-forming reaction, first reported by Abidi and later shown by Corey and co-workers to proceed through allylic nitro intermediates, ultimately led to a practical and powerful synthesis of alkynes starting from beta-keto esters.
Withaferin A - Wikipedia
Withaferin A is a steroidal lactone, derived from Acnistus arborescens, Withania somnifera (Indian Winter cherry or Ashwagandha in Sanskrit) and other members of Solanaceae family. It has been traditionally used in ayurvedic medicine. It is the first member of the withanolide class of ergostane type product to be discovered. This natural product has wide range of pharmacological activities including cardioprotective, anti-inflammatory, immuno-modulatory, anti-angiogenesis, anti-metastasis and anti-carcinogenic properties. Withanolides are a group of naturally occurring C28- steroidal lactones. They contain four cycloalkane ring structures, three cyclohexane rings and one cyclopentane ring. Withaferin A is highly reactive because of the ketone-containing unsaturated A ring, the epoxide in the B ring, and the unsaturated lactone ring. The double bond in ring A and the epoxide ring are mainly responsible for the cytotoxicity. The 22nd and 26th carbons of the ergostane skeleton in withaferin A and ...
Cardenolide - Wikipedia
Cardenolide is a type of steroid. Many plants contain derivatives, collectively known as cardenolides, including many in the form of cardenolide glycosides (cardenolides that contain structural groups derived from sugars). Cardenolide glycosides are often toxic; specifically, they are heart-arresting. The term derives card- heart (from Greek καρδία kardiā) and the suffix -enolide, referring to the lactone ring at C17. It should not be confused with cardanolides. Cardanolides are a class of steroids (or aglycones if viewed as cardiac glycoside constituents), and cardenolides are a subtype of this class (see MeSH D codes list). Cardenolides are C(23)-steroids with methyl groups at C-10 and C-13 and a five-membered lactone (specifically a butenolide) at C-17. They are aglycone constituents of cardiac glycosides and must have at least one double bond in the molecule. The class includes cardadienolides and cardatrienolides. Members include: acetyldigitoxins acetyldigoxins cymarine digitoxin ...
... (or cymarine) is a cardiac glycoside. Plants of the genus Apocynum, including Apocynum cannabinum and Apocynum venetum ...
National Center for Biotechnology Information, U.S. National Library of Medicine, Cymarine "Apocynum L." Plants of the World ...
Members include: acetyldigitoxins acetyldigoxins cymarine digitoxin digitoxigenin digoxigenin digoxin medigoxin neoconvalloside ...
List of MeSH codes (D09)
... cymarine MeSH D09.408.180.810.600 - ouabain MeSH D09.408.210.209 - chromomycin a3 MeSH D09.408.320.500 - methylgalactosides ...
List of MeSH codes (D04)
... cymarine MeSH D04.808.155.580.810.600 - ouabain MeSH D04.808.221.263 - cholenes MeSH D04.808.221.430 - cholic acids MeSH ... cymarine MeSH D04.808.155.160.861.600 - ouabain MeSH D04.808.155.160.861.700 - strophanthidin MeSH D04.808.155.580 - cardiac ...
Cymarin - Wikipedia
Mobil Stern Tube Lubricant
Strophanthins | Harvard Catalyst Profiles | Harvard Catalyst
Strophanthins - DrugBank
Apocynum - Wikipedia
2016 ACC/AHA Clinical Performance and Quality Measures for Adults With Atrial Fibrillation or Atrial Flutter | JACC: Journal of...
The Culture of Chemistry: Sweet Hearts and Frogs
use CYMARINE to search TSIMARIN 1975-92. History Note:. 91(75); was see under STROPHANTHINS 1975-90; TSIMARIN was see CYMARINE ... Cymarine - Preferred Concept UI. M0005498. Scope note. A cardiotonic cardiac glycoside found in STROPHANTHUS. The aglycone is ... Cymarine Entry term(s):. Cymarin. Strophantisel. Tsimarin. Zimarin. h Strophanthin. h-Strophanthin. k Strophanthin alpha. k- ... 91; was see under STROPHANTHINS 1975-90; TSIMARIN was see CYMARINE 1975-92. ...
DeCS Ingl s+escopo
Cymarine .. Cymarin .. Strophantisel .. Tsimarin .. Zimarin .. h Strophanthin .. k Strophanthin alpha .. h-Strophanthin .. k- ... D09.408.180.810.250 Cymarine .. HP4 Materia Medica .. HP4.018 Homeopathic Remedy .. HP4.018.127 Homeopathic Remedy A .. HP4.018 ... D04.210.500.155.580.130.750.250 Cymarine .. D04.210.500.155.580.130.750.800 Strophanthidin .. D09 Carbohydrates .. D09.408 ...
Flying and Aviation Magazine Aeronautics | Volume 1 - No. 6 - 1907 December
Additional pages Product Categories - Healthmatics | Page 302
most toxic plant poison - Everything2.com
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DeCS 2013 - December 17, 2013 version
DeCS 2013 - July 15, 2013 version
DeCS 2008 - versión 17 de Marzo de 2008
DeCS 2011 - December 22, 2011 version
DeCS 2012 - February 22, 2012 version
DeCS 2010 - February 12, 2010 version
DeCS 2009 - February 20, 2009 version
DeCS 2010 - February 12, 2010 version
- National Center for Biotechnology Information, U.S. National Library of Medicine, Cymarine "Apocynum L." Plants of the World Online. (wikipedia.org)
- Cymarine a compound of the digitalis glycoside type, found in the Strophantus variety of a tropical creeping shrub . (everything2.com)