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Sample records for binding volatile anesthetics

  1. Effect of four-alpha-helix bundle cavity size on volatile anesthetic binding energetics.

    Science.gov (United States)

    Manderson, Gavin A; Michalsky, Stuart J; Johansson, Jonas S

    2003-09-30

    Currently, it is thought that inhalational anesthetics cause anesthesia by binding to ligand-gated ion channels. This is being investigated using four-alpha-helix bundles, small water-soluble analogues of the transmembrane domains of the "natural" receptor proteins. The study presented here specifically investigates how multiple alanine-to-valine substitutions (which each decrease the volume of the internal binding cavity by 38 A(3)) affect structure, stability, and anesthetic binding affinity of the four-alpha-helix bundles. Structure remains essentially unchanged when up to four alanine residues are changed to valine. However, stability increases as the number of these substitutions is increased. Anesthetic binding affinities are also affected. Halothane binds to the four-alpha-helix bundle variants with 0, 1, and 2 substitutions with equivalent affinities but binds to the variants with 3 and 4 more tightly. The same order of binding affinities was observed for chloroform, although for a particular variant, chloroform was bound less tightly. The observed differences in binding affinities may be explained in terms of a modulation of van der Waals and hydrophobic interactions between ligand and receptor. These, in turn, could result from increased four-alpha-helix bundle binding cavity hydrophobicity, a decrease in cavity size, or improved ligand/receptor shape complementarity.

  2. CARDIOPROTECTION BY VOLATILE ANESTHETICS: FROM BENCH TO BEDSIDE AND BACK

    OpenAIRE

    Sedlić, Filip; Šepac, A; Muravyeva, M; Bošnjak, Željko

    2011-01-01

    Ischemia and reperfusion (I/R) injury of the heart can be ameliorated by volatile anesthetics (VAs). Application of VAs prior to the ischemic event triggers endogenous cardioprotective program that persists even after anesthetic removal, and it is called anesthetic-induced preconditioning (APC) (1). VAs can also reduce infarct size if applied during the reperfusion period (anesthetic postconditioning), where they can also exert protection by the direct effects on cardiac cel...

  3. Goalpha regulates volatile anesthetic action in Caenorhabditis elegans.

    Science.gov (United States)

    van Swinderen, B; Metz, L B; Shebester, L D; Mendel, J E; Sternberg, P W; Crowder, C M

    2001-06-01

    To identify genes controlling volatile anesthetic (VA) action, we have screened through existing Caenorhabditis elegans mutants and found that strains with a reduction in Go signaling are VA resistant. Loss-of-function mutants of the gene goa-1, which codes for the alpha-subunit of Go, have EC(50)s for the VA isoflurane of 1.7- to 2.4-fold that of wild type. Strains overexpressing egl-10, which codes for an RGS protein negatively regulating goa-1, are also isoflurane resistant. However, sensitivity to halothane, a structurally distinct VA, is differentially affected by Go pathway mutants. The RGS overexpressing strains, a goa-1 missense mutant found to carry a novel mutation near the GTP-binding domain, and eat-16(rf) mutants, which suppress goa-1(gf) mutations, are all halothane resistant; goa-1(null) mutants have wild-type sensitivities. Double mutant strains carrying mutations in both goa-1 and unc-64, which codes for a neuronal syntaxin previously found to regulate VA sensitivity, show that the syntaxin mutant phenotypes depend in part on goa-1 expression. Pharmacological assays using the cholinesterase inhibitor aldicarb suggest that VAs and GOA-1 similarly downregulate cholinergic neurotransmitter release in C. elegans. Thus, the mechanism of action of VAs in C. elegans is regulated by Goalpha, and presynaptic Goalpha-effectors are candidate VA molecular targets.

  4. A Unitary Anesthetic Binding Site at High Resolution

    Energy Technology Data Exchange (ETDEWEB)

    Vedula, L. Sangeetha; Brannigan, Grace; Economou, Nicoleta J.; Xi, Jin; Hall, Michael A.; Liu, Renyu; Rossi, Matthew J.; Dailey, William P.; Grasty, Kimberly C.; Klein, Michael L.; Eckenhoff, Roderic G.; Loll, Patrick J.; (Drexel-MED); (UPENN)

    2009-10-21

    Propofol is the most widely used injectable general anesthetic. Its targets include ligand-gated ion channels such as the GABA{sub A} receptor, but such receptor-channel complexes remain challenging to study at atomic resolution. Until structural biology methods advance to the point of being able to deal with systems such as the GABA{sub A} receptor, it will be necessary to use more tractable surrogates to probe the molecular details of anesthetic recognition. We have previously shown that recognition of inhalational general anesthetics by the model protein apoferritin closely mirrors recognition by more complex and clinically relevant protein targets; here we show that apoferritin also binds propofol and related GABAergic anesthetics, and that the same binding site mediates recognition of both inhalational and injectable anesthetics. Apoferritin binding affinities for a series of propofol analogs were found to be strongly correlated with the ability to potentiate GABA responses at GABA{sub A} receptors, validating this model system for injectable anesthetics. High resolution x-ray crystal structures reveal that, despite the presence of hydrogen bond donors and acceptors, anesthetic recognition is mediated largely by van der Waals forces and the hydrophobic effect. Molecular dynamics simulations indicate that the ligands undergo considerable fluctuations about their equilibrium positions. Finally, apoferritin displays both structural and dynamic responses to anesthetic binding, which may mimic changes elicited by anesthetics in physiologic targets like ion channels.

  5. A Unitary Anesthetic-Binding Site at High Resolution

    Energy Technology Data Exchange (ETDEWEB)

    Vedula, L.; Brannigan, G; Economou, N; Xi, J; Hall, M; Liu, R; Rossi, M; Dailey, W; Grasty, K; et. al.

    2009-01-01

    Propofol is the most widely used injectable general anesthetic. Its targets include ligand-gated ion channels such as the GABAA receptor, but such receptor-channel complexes remain challenging to study at atomic resolution. Until structural biology methods advance to the point of being able to deal with systems such as the GABA{sub A} receptor, it will be necessary to use more tractable surrogates to probe the molecular details of anesthetic recognition. We have previously shown that recognition of inhalational general anesthetics by the model protein apoferritin closely mirrors recognition by more complex and clinically relevant protein targets; here we show that apoferritin also binds propofol and related GABAergic anesthetics, and that the same binding site mediates recognition of both inhalational and injectable anesthetics. Apoferritin binding affinities for a series of propofol analogs were found to be strongly correlated with the ability to potentiate GABA responses at GABA{sub A} receptors, validating this model system for injectable anesthetics. High resolution x-ray crystal structures reveal that, despite the presence of hydrogen bond donors and acceptors, anesthetic recognition is mediated largely by van der Waals forces and the hydrophobic effect. Molecular dynamics simulations indicate that the ligands undergo considerable fluctuations about their equilibrium positions. Finally, apoferritin displays both structural and dynamic responses to anesthetic binding, which may mimic changes elicited by anesthetics in physiologic targets like ion channels.

  6. A Unitary Anesthetic Binding Site at High Resolution

    Energy Technology Data Exchange (ETDEWEB)

    L Vedula; G Brannigan; N Economou; J Xi; M Hall; R Liu; M Rossi; W Dailey; K Grasty; et. al.

    2011-12-31

    Propofol is the most widely used injectable general anesthetic. Its targets include ligand-gated ion channels such as the GABA{sub A} receptor, but such receptor-channel complexes remain challenging to study at atomic resolution. Until structural biology methods advance to the point of being able to deal with systems such as the GABA{sub A} receptor, it will be necessary to use more tractable surrogates to probe the molecular details of anesthetic recognition. We have previously shown that recognition of inhalational general anesthetics by the model protein apoferritin closely mirrors recognition by more complex and clinically relevant protein targets; here we show that apoferritin also binds propofol and related GABAergic anesthetics, and that the same binding site mediates recognition of both inhalational and injectable anesthetics. Apoferritin binding affinities for a series of propofol analogs were found to be strongly correlated with the ability to potentiate GABA responses at GABA{sub A} receptors, validating this model system for injectable anesthetics. High resolution x-ray crystal structures reveal that, despite the presence of hydrogen bond donors and acceptors, anesthetic recognition is mediated largely by van der Waals forces and the hydrophobic effect. Molecular dynamics simulations indicate that the ligands undergo considerable fluctuations about their equilibrium positions. Finally, apoferritin displays both structural and dynamic responses to anesthetic binding, which may mimic changes elicited by anesthetics in physiologic targets like ion channels.

  7. Glutamatergic Neurotransmission Links Sensitivity to Volatile Anesthetics with Mitochondrial Function.

    Science.gov (United States)

    Zimin, Pavel I; Woods, Christian B; Quintana, Albert; Ramirez, Jan-Marino; Morgan, Philip G; Sedensky, Margaret M

    2016-08-22

    An enigma of modern medicine has persisted for over 150 years. The mechanisms by which volatile anesthetics (VAs) produce their effects (loss of consciousness, analgesia, amnesia, and immobility) remain an unsolved mystery. Many attractive putative molecular targets have failed to produce a significant effect when genetically tested in whole-animal models [1-3]. However, mitochondrial defects increase VA sensitivity in diverse organisms from nematodes to humans [4-6]. Ndufs4 knockout (KO) mice lack a subunit of mitochondrial complex I and are strikingly hypersensitive to VAs yet resistant to the intravenous anesthetic ketamine [7]. The change in VA sensitivity is the largest reported for a mammal. Limiting NDUFS4 loss to a subset of glutamatergic neurons recapitulates the VA hypersensitivity of Ndufs4(KO) mice, while loss in GABAergic or cholinergic neurons does not. Baseline electrophysiologic function of CA1 pyramidal neurons does not differ between Ndufs4(KO) and control mice. Isoflurane concentrations that anesthetize only Ndufs4(KO) mice (0.6%) decreased the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) only in Ndufs4(KO) CA1 neurons, while concentrations effective in control mice (1.2%) decreased sEPSC frequencies in both control and Ndufs4(KO) CA1 pyramidal cells. Spontaneous inhibitory postsynaptic currents (sIPSCs) were not differentially affected between genotypes. The effects of isoflurane were similar on evoked field excitatory postsynaptic potentials (fEPSPs) and paired pulse facilitation (PPF) in KO and control hippocampal slices. We propose that CA1 presynaptic excitatory neurotransmission is hypersensitive to isoflurane in Ndufs4(KO) mice due to the inhibition of pre-existing reduced complex I function, reaching a critical reduction that can no longer meet metabolic demands.

  8. Crystal structure of isoflurane bound to integrin LFA-1 supports a unified mechanism of volatile anesthetic action in the immune and central nervous systems

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongmin; Astrof, Nathan S.; Liu, Jin-Huan; Wang, Jia-huai; Shimaoka, Motomu; (Harvard-Med); (DFCI)

    2009-09-15

    Volatile anesthetics (VAs), such as isoflurane, induce a general anesthetic state by binding to specific targets (i.e., ion channels) in the central nervous system (CNS). Simultaneously, VAs modulate immune functions, possibly via direct interaction with alternative targets on leukocytes. One such target, the integrin lymphocyte function-associated antigen-1 (LFA-1), has been shown previously to be inhibited by isoflurane. A better understanding of the mechanism by which isoflurane alters protein function requires the detailed information about the drug-protein interaction at an atomic level. Here, we describe the crystal structure of the LFA-1 ligand-binding domain (I domain) in complex with isoflurane at 1.6 {angstrom}. We discovered that isoflurane binds to an allosteric cavity previously implicated as critical for the transition of LFA-1 from the low- to the high-affinity state. The isoflurane binding site in the I domain involves an array of amphiphilic interactions, thereby resembling a 'common anesthetic binding motif' previously predicted for authentic VA binding sites. These results suggest that the allosteric modulation of protein function by isoflurane, as demonstrated for the integrin LFA-1, might represent a unified mechanism shared by the interactions of volatile anesthetics with targets in the CNS. Crystal structure of isoflurane bound to integrin LFA-1 supports a unified mechanism of volatile anesthetic action in the immune and central nervous systems.

  9. Development of three Drosophila melanogaster strains with different sensitivity to volatile anesthetics

    Institute of Scientific and Technical Information of China (English)

    LIU Jin; HU Zhao-yang; YE Qi-quan; DAI Shuo-hua

    2009-01-01

    Background The mechanisms of action for volatile anesthetics remain unknown for centuries partly owing to the insufficient or ineffective research models. We designed this study to develop three strains derived from a wild-type Drosophila melanogaster with different sensitivities to volatile anesthetics, which may ultimately facilitate molecular and genetic studies of the mechanism involved.Methods Median effective doses (ED50) of sevoflurane in seven-day-old virgin female and male wild-type Drosophila melanogaster were determined. The sensitive males and females of percentile 6-10 were cultured for breeding sensitive offspring (S1). So did median ones of percentile 48-52 for breeding median offspring (M1), resistant ones of percentile 91-95 for breeding resistant offspring (R1). Process was repeated through 31 generations, in the 37th generation, S37,M37 and R37 were used to determine ED50 for enflurane, isoflurane, sevoflurane, desflurane, halothane, methoxyflurane,chloroform and trichloroethylene, then ED50 values were correlated with minimum alveolar concentration (MAC) values in human.Results From a wild-type Drosophila melanogaster we were able to breed three strains with high, median and low sevoflurane requirements. The ratio of sevoflurane requirements of three strains were 1.20:1.00:0.53 for females and 1.22:1.00:0.72 for males. Strains sensitive, median and resistant to sevoflurane were also sensitive, median and resistant to other volatile anesthetics. For eight anesthetics, ED50 values in three strains correlated directly with MAC values in human.Conclusions Three Drosophila me/anogaster strains with high, median and low sensitivity to volatile anesthetics, but with same hereditary background were developed. The ED50 are directly correlated with MAC in human for eight volatile anesthetics.

  10. Volatile anesthetic for the control of posthypoxic refractory myoclonic status

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    Vivek Rayadurg

    2016-01-01

    Full Text Available Posthypoxic myoclonus (Lance-Adams syndrome is characterized by myoclonus involving multiple muscle groups which is resistant to most conventional antiepileptic drugs. We present a case of hypoxic brain injury-induced myoclonic status epilepticus successfully controlled with isoflurane. The antimyoclonic effects of isoflurane are likely due to potentiation of inhibitory postsynaptic GABA A receptor-mediated currents and its effects on thalamocortical pathways. It is effective even when intravenous agents fail to control myoclonus. It may be a useful alternative to intravenous anesthetics as a third tier therapy in patients with refractory status myoclonus.

  11. Volatile anesthetics inhibit the activity of calmodulin by interacting with its hydrophobic site

    Institute of Scientific and Technical Information of China (English)

    ZHOU Miao-miao; XIA Hui-min; LIU Jiao; XU You-nian; XIN Nai-xin; ZHANG Shi-hai

    2012-01-01

    Background Volatile anesthetics (VAs) may affect varied and complex physiology processes by manipulating Ca2+-calmodulin (CaM).However,the detailed mechanism about the action of VAs on CaM has not been elucidated.This study was undertaken to examine the effects of VAs on the conformational change,hydrophobic site,and downstream signaling pathway of CaM,to explore the possible mechanism of anesthetic action of VAs.Methods Real-time second-harmonic generation (SHG) was performed to monitor the conformational change of CaM in the presence of VAs, each plus 100 μmol/L Ca2+. A hydrophobic fluorescence indicator,8-anilinonaphthalene-1-sulfonate (ANS),was utilized to define whether the VAs would interact with CaM at the hydrophobic site or not.High-performance liquid chromatography (HPLC) was carried out to analyze the activity of CaM-dependent phosphodiesterase (PDE1) in the presence of VAs.The VAs studied were ether,enflurane,isoflurane,and sevoflurane,with their aqueous concentrations 7.6,9.5,11.4 mmol/L; 0.42,0.52,0.62 mmol/L; 0.25,0.31,0.37 mmol/L and 0.47,0.59,0.71 mmol/L respectively,each were equivalent to their 0.8,1.0 and 1.2 concentration for 50% of maximal effect (EC50) for general anesthesia.Results The second-harmonic radiation of CaM in the presence of Ca2+ was largely inhibited by the VAs.The fluorescence intensity of ANS,generated by binding of Ca2+ to CaM,was reversed by the VAs.HPLC results also showed that AMP,the product of the hydrolysis of cAMP by CaM-dependent PDE1,was reduced by the VAs.Conclusions Our findings demonstrate that the above VAs interact with the hydrophobic core of Ca2+-CaM and the interaction results in the inhibition of the conformational change and activity of CaM.This in vitro study may provide us insight into the possible mechanism of anesthetic action of VAs in vivo.

  12. Volatile Anesthetics. Is a New Player Emerging in Critical Care Sedation?

    Science.gov (United States)

    Jerath, Angela; Parotto, Matteo; Wasowicz, Marcin; Ferguson, Niall D

    2016-06-01

    Volatile anesthetic agent use in the intensive care unit, aided by technological advances, has become more accessible to critical care physicians. With increasing concern over adverse patient consequences associated with our current sedation practice, there is growing interest to find non-benzodiazepine-based alternative sedatives. Research has demonstrated that volatile-based sedation may provide superior awakening and extubation times in comparison with current intravenous sedation agents (propofol and benzodiazepines). Volatile agents may possess important end-organ protective properties mediated via cytoprotective and antiinflammatory mechanisms. However, like all sedatives, volatile agents are capable of deeply sedating patients, which can have respiratory depressant effects and reduce patient mobility. This review seeks to critically appraise current volatile use in critical care medicine including current research, technical consideration of their use, contraindications, areas of controversy, and proposed future research topics.

  13. Volatile Anesthetics Influence Blood-Brain Barrier Integrity by Modulation of Tight Junction Protein Expression in Traumatic Brain Injury

    OpenAIRE

    Thal, Serge C.; Clara Luh; Eva-Verena Schaible; Ralph Timaru-Kast; Jana Hedrich; Luhmann, Heiko J.; Kristin Engelhard; Zehendner, Christoph M.

    2012-01-01

    Disruption of the blood-brain barrier (BBB) results in cerebral edema formation, which is a major cause for high mortalityrnafter traumatic brain injury (TBI). As anesthetic care is mandatory in patients suffering from severe TBI it may be importantrnto elucidate the effect of different anesthetics on cerebral edema formation. Tight junction proteins (TJ) such as zonularnoccludens-1 (ZO-1) and claudin-5 (cl5) play a central role for BBB stability. First, the influence of the volatile anesthet...

  14. Does chronic occupational exposure to volatile anesthetic agents influence the rate of neutrophil apoptosis?

    LENUS (Irish Health Repository)

    Goto, Y

    2012-02-03

    PURPOSE: The purpose of this preliminary investigation was to determine whether the rate of neutrophil apoptosis in health care workers is influenced by exposure to volatile anesthetic agents. METHODS: Percentage neutrophil apoptosis (Annexin-V FITC assay) was measured in health care workers (n = 20) and unexposed volunteers (n = 10). For the health care workers, time weighted personal exposure monitoring to N2O, sevoflurane and isoflurane was carried out. RESULTS: The sevoflurane and isoflurane concentrations to which health care workers were exposed were less than recommended levels in all 20 cases. Percent apoptosis was less at 24 (but not at one and 12) hr culture in health care workers [50.5 (9.7)%; P = 0.008] than in unexposed volunteers [57.3 (5.1)%]. CONCLUSION: Inhibition of neutrophil apoptosis at 24 hr culture was demonstrated in health care workers chronically exposed to volatile anesthetic agents. Exposure was well below recommended levels in the both scavenged and unscavenged work areas in which the study was carried out. Further study is required to assess the effect of greater degrees of chronic exposure to volatile anesthetic agents on neutrophil apoptosis.

  15. Volatile anesthetics influence blood-brain barrier integrity by modulation of tight junction protein expression in traumatic brain injury.

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    Serge C Thal

    Full Text Available Disruption of the blood-brain barrier (BBB results in cerebral edema formation, which is a major cause for high mortality after traumatic brain injury (TBI. As anesthetic care is mandatory in patients suffering from severe TBI it may be important to elucidate the effect of different anesthetics on cerebral edema formation. Tight junction proteins (TJ such as zonula occludens-1 (ZO-1 and claudin-5 (cl5 play a central role for BBB stability. First, the influence of the volatile anesthetics sevoflurane and isoflurane on in-vitro BBB integrity was investigated by quantification of the electrical resistance (TEER in murine brain endothelial monolayers and neurovascular co-cultures of the BBB. Secondly brain edema and TJ expression of ZO-1 and cl5 were measured in-vivo after exposure towards volatile anesthetics in native mice and after controlled cortical impact (CCI. In in-vitro endothelial monocultures, both anesthetics significantly reduced TEER within 24 hours after exposure. In BBB co-cultures mimicking the neurovascular unit (NVU volatile anesthetics had no impact on TEER. In healthy mice, anesthesia did not influence brain water content and TJ expression, while 24 hours after CCI brain water content increased significantly stronger with isoflurane compared to sevoflurane. In line with the brain edema data, ZO-1 expression was significantly higher in sevoflurane compared to isoflurane exposed CCI animals. Immunohistochemical analyses revealed disruption of ZO-1 at the cerebrovascular level, while cl5 was less affected in the pericontusional area. The study demonstrates that anesthetics influence brain edema formation after experimental TBI. This effect may be attributed to modulation of BBB permeability by differential TJ protein expression. Therefore, selection of anesthetics may influence the barrier function and introduce a strong bias in experimental research on pathophysiology of BBB dysfunction. Future research is required to investigate

  16. Comparison of pneumotachography and anemometery for flow measurement during mechanical ventilation with volatile anesthetics.

    Science.gov (United States)

    Mondoñedo, Jarred R; Herrmann, Jacob; McNeil, John S; Kaczka, David W

    2016-11-14

    Volatile anesthetics alter the physical properties of inhaled gases, such as density and viscosity. We hypothesized that the use of these agents during mechanical ventilation would yield systematic biases in estimates of flow ([Formula: see text]) and tidal volume (V T) for two commonly used flowmeters: the pneumotachograph (PNT), which measures a differential pressure across a calibrated resistive element, and the hot-wire anemometer (HWA), which operates based on convective heat transfer from a current-carrying wire to a flowing gas. We measured [Formula: see text] during ventilation of a spring-loaded mechanical test lung, using both the PNT and HWA placed in series at the airway opening. Delivered V T was estimated from the numerically-integrated [Formula: see text]. Measurements were acquired under baseline conditions with room air, and during ventilation with increasing concentrations of isoflurane, sevoflurane, and desflurane. We also evaluated a simple compensation technique for HWA flow, which accounted for changes in gas mixture density. We found that discrepancies in estimated V T between the PNT and HWA occurred during ventilation with isoflurane (6.3 ± 3.0%), sevoflurane (10.0 ± 7.3%), and desflurane (25.8 ± 17.2%) compared to baseline conditions. The magnitude of these discrepancies increased with anesthetic concentration. A simple compensation factor based on density reduced observed differences between the flowmeters, regardless of the anesthetic or concentration. These data indicate that the choice and concentration of anesthetic agents are primary factors for differences in estimated V T between the PNT and HWA. Such discrepancies may be compensated by accounting for alterations in gas density.

  17. Recognition of anesthetic barbiturates by a protein binding site: a high resolution structural analysis.

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    Simon Oakley

    Full Text Available Barbiturates potentiate GABA actions at the GABA(A receptor and act as central nervous system depressants that can induce effects ranging from sedation to general anesthesia. No structural information has been available about how barbiturates are recognized by their protein targets. For this reason, we tested whether these drugs were able to bind specifically to horse spleen apoferritin, a model protein that has previously been shown to bind many anesthetic agents with affinities that are closely correlated with anesthetic potency. Thiopental, pentobarbital, and phenobarbital were all found to bind to apoferritin with affinities ranging from 10-500 µM, approximately matching the concentrations required to produce anesthetic and GABAergic responses. X-ray crystal structures were determined for the complexes of apoferritin with thiopental and pentobarbital at resolutions of 1.9 and 2.0 Å, respectively. These structures reveal that the barbiturates bind to a cavity in the apoferritin shell that also binds haloalkanes, halogenated ethers, and propofol. Unlike these other general anesthetics, however, which rely entirely upon van der Waals interactions and the hydrophobic effect for recognition, the barbiturates are recognized in the apoferritin site using a mixture of both polar and nonpolar interactions. These results suggest that any protein binding site that is able to recognize and respond to the chemically and structurally diverse set of compounds used as general anesthetics is likely to include a versatile mixture of both polar and hydrophobic elements.

  18. Paired assessment of volatile anesthetic concentrations with synaptic actions recorded in vitro.

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    Stuart J McDougall

    Full Text Available The volatile anesthetic isoflurane poses a number of experimental challenges in the laboratory. Due to its rapid evaporation, the open conditions of most in vitro electrophysiological recording systems make the determination of actual isoflurane concentrations a challenge. Since the absolute anesthetic concentration in solution is directly related to efficacy, concentration measurements are important to allow comparisons between laboratory and clinical studies. In this study we quantify the sources of isoflurane loss during experimentation and describe a method for the measurement of isoflurane concentrations using gas chromatography and mass spectrometry simultaneous to in vitro electrophysiological measurements. Serial samples of perfused bath solution allowed correlation of isoflurane concentrations with ongoing biological effects. Saturated physiological solutions contained 13.4 +/- 0.2 mM isoflurane and were diluted to desired "nominal" concentrations for experiments. The perfusion system established stable isoflurane concentrations within the bath by 2 minutes. However, bath isoflurane concentrations varied substantially and unpredictably between experiments. The magnitudes of such discrepancies in isoflurane concentrations spanned clinically important levels. Our studies suggest that, despite countermeasures, solution handling significantly impacted the isoflurane content in the tissue bath. The magnitude of these discrepancies appears to necessitate systematic direct measurement of bath isoflurane concentrations during most in vitro conditions.

  19. Bisphenol A binds to the local anesthetic receptor site to block the human cardiac sodium channel.

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    Andrias O O'Reilly

    Full Text Available Bisphenol A (BPA has attracted considerable public attention as it leaches from plastic used in food containers, is detectable in human fluids and recent epidemiologic studies link BPA exposure with diseases including cardiovascular disorders. As heart-toxicity may derive from modified cardiac electrophysiology, we investigated the interaction between BPA and hNav1.5, the predominant voltage-gated sodium channel subtype expressed in the human heart. Electrophysiology studies of heterologously-expressed hNav1.5 determined that BPA blocks the channel with a K(d of 25.4±1.3 µM. By comparing the effects of BPA and the local anesthetic mexiletine on wild type hNav1.5 and the F1760A mutant, we demonstrate that both compounds share an overlapping binding site. With a key binding determinant thus identified, an homology model of hNav1.5 was generated based on the recently-reported crystal structure of the bacterial voltage-gated sodium channel NavAb. Docking predictions position both ligands in a cavity delimited by F1760 and contiguous with the DIII-IV pore fenestration. Steered molecular dynamics simulations used to assess routes of ligand ingress indicate that the DIII-IV pore fenestration is a viable access pathway. Therefore BPA block of the human heart sodium channel involves the local anesthetic receptor and both BPA and mexiletine may enter the closed-state pore via membrane-located side fenestrations.

  20. [Binding of Volatile Organic Compounds to Edible Biopolymers].

    Science.gov (United States)

    Misharina, T A; Terenina, M B; Krikunova, N I; Medvedeva, I B

    2016-01-01

    Capillary gas chromatography was used to study the influence of the composition and structure of different edible polymers (polysaccharides, vegetable fibers, and animal protein gelatin) on the binding of essential oil components. The retention of volatile organic compounds on biopolymers was shown to depend on their molecule structure and the presence, type, and position of a functional group. The maximum extent of the binding was observed for nonpolar terpene and sesquiterpene hydrocarbons, and the minimum extent was observed for alcohols. The components of essential oils were adsorbed due mostly to hydrophobic interactions. It was shown that the composition and structure of a compound, its physico-chemical state, and the presence of functional groups influence the binding. Gum arabic and guar gum were found to bind nonpolar compounds to a maximum and minimum extent, respectively. It was demonstrated the minimum adsorption ability of locust bean gum with respect to all studied compounds.

  1. Shaker-Related Potassium Channels in the Central Medial Nucleus of the Thalamus Are Important Molecular Targets for Arousal Suppression by Volatile General Anesthetics

    Science.gov (United States)

    Birch, Alexandra M.; Tanaka, Brian S.; Sokolov, Yuri; Goldin, Alan L.; Chandy, K. George; Hall, James E.; Alkire, Michael T.

    2013-01-01

    The molecular targets and neural circuits that underlie general anesthesia are not fully elucidated. Here, we directly demonstrate that Kv1-family (Shaker-related) delayed rectifier K+ channels in the central medial thalamic nucleus (CMT) are important targets for volatile anesthetics. The modulation of Kv1 channels by volatiles is network specific as microinfusion of ShK, a potent inhibitor of Kv1.1, Kv1.3, and Kv1.6 channels, into the CMT awakened sevoflurane-anesthetized rodents. In heterologous expression systems, sevoflurane, isoflurane, and desflurane at subsurgical concentrations potentiated delayed rectifier Kv1 channels at low depolarizing potentials. In mouse thalamic brain slices, sevoflurane inhibited firing frequency and delayed the onset of action potentials in CMT neurons, and ShK-186, a Kv1.3-selective inhibitor, prevented these effects. Our findings demonstrate the exquisite sensitivity of delayed rectifier Kv1 channels to modulation by volatile anesthetics and highlight an arousal suppressing role of Kv1 channels in CMT neurons during the process of anesthesia. PMID:24107962

  2. The use of a volatile anesthetic regimen protects against acute normovolemic hemodilution induced myocardial depression in patients with coronary artery disease

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    Lorsomradee Sratwadee

    2009-01-01

    Full Text Available Background: Previous studies indicated that acute normovolemic hemodilution (ANH was associated with a depression of myocardial function in coronary surgery patients with baseline heart rate faster than 90 bpm. It was suggested that this phenomenon could be explained by the occurrence of myocardial ischemia. In the present study, we hypothesized that the cardioprotective properties of a volatile anesthetic regimen might protect against the ANH related myocardial functional impairment. Materials and Methods: Forty elective coronary surgery patients with baseline heart rate faster than 90 bpm were randomly allocated to receive different anesthetic regimens. Group A (n = 20 received midazolam-based anesthesia. Group B (n = 20 received a sevoflurane-based anesthesia. Five-lead electrocardiogram, pulse oximetry, capnography, radial arterial pressure, and Swan Ganz continuous thermodilution cardiac output via right internal jugular vein were monitored. Measurements were obtained before and after ANH. Data were compared using paired t test. All data were expressed as mean ± SD. Data were considered significant if P < 0.05. Results: After ANH, systemic vascular resistance was slightly decreased in group A while there was a significant decrease in group B. In group A, cardiac output was slightly decreased from 5.07±1.17 l/min to 5.02±1.28 l/min after ANH, whereas in group B, cardiac output was significantly increased from 4.84±1.21 l/min to 6.02±1.28 l/min after ANH. Conclusion: In coronary surgery patients, with baseline heart rate faster than 90 bpm, anesthesia with sevoflurane during ANH was associated with an improvement in myocardial function after ANH, which was not present in patients anesthetized with midazolam.

  3. Anesthetic management of comprehensive dental restoration in a child with glutaric aciduria type 1 using volatile sevoflurane.

    Science.gov (United States)

    Teng, Wei-Nung; Lin, Su-Man; Niu, Dau-Ming; Kuo, Yi-Min; Chan, Kwok-Hon; Sung, Chun-Sung

    2014-10-01

    Glutaric aciduria type 1 (GA1) is a rare, inherited mitochondrial disorder that results from deficiency of mitochondrial glutaryl-CoA dehydrogenase. Most patients develop neurological dysfunction early in life, which leads to severe disabilities. We present a 37-month-old girl with GA1 manifested as macrocephaly and hypotonia who received comprehensive dental restoration surgery under general anesthesia with sevoflurane. She was placed on specialized fluid management during a preoperative fasting period and anesthesia was administered without complications. All the physiological parameters, including glucose and lactate blood levels and arterial blood gas were carefully monitored and maintained within normal range perioperatively. Strategies for anesthetic management should include prevention of pulmonary aspiration, dehydration, hyperthermia and catabolic state, adequate analgesia to minimize surgical stress, and avoidance of prolonged neuromuscular blockade. We administered general anesthesia with sevoflurane uneventfully, which was well tolerated by our patient with GA1. Additionally, communication with a pediatric geneticist and surgeons should be undertaken to formulate a comprehensive anesthetic strategy in these patients.

  4. Day-surgery patients anesthetized with propofol have less postoperative pain than those anesthetized with sevoflurane.

    LENUS (Irish Health Repository)

    Tan, Terry

    2012-02-01

    BACKGROUND: There have been recent studies suggesting that patients anesthetized with propofol have less postoperative pain compared with patients anesthetized with volatile anesthetics. METHODS: In this randomized, double-blind study, 80 patients undergoing day-case diagnostic laparoscopic gynecological surgery were either anesthetized with IV propofol or sevoflurane. The primary outcome measured was pain on a visual analog scale. RESULTS: Patients anesthetized with propofol had less pain compared with patients anesthetized with sevoflurane (P = 0.01). There was no difference in any of the other measured clinical outcomes. CONCLUSIONS: The patients anesthetized with propofol appeared to have less pain than patients anesthetized with sevoflurane.

  5. Interference of diabetes on volatile anesthetic-induced myocardial protection%糖尿病与吸入性麻醉药心肌保护作用研究新进展

    Institute of Scientific and Technical Information of China (English)

    李毅; 江晓菁; 师恩祎

    2009-01-01

    Volatile anesthetic pre-or post-conditioning presents protective effects against iscbemic damage of myocardium,by activating endogeneous protection mechanisms.Recent studies show that hyperglycemia may block anesthetic conditioning-induced protective effect,and that volatile anesthetics inhibit insulin release,producing hyperglycemia.Volatile anesthetic-produced myocardial protective effects may have a promising future in clinical application,and more attention should be paid on the relationship between diabetes and myocardial protection of volatile anesthetic.%目前研究表明,对于心肌缺血/再灌注(isehemic/reperfusion,I/R)损伤,适当的刺激可以激活机体的内源性保护机制,即缺血预处理(ischemic preconditioning,IPC)和缺血后处理(ischemic postconditioning,I-post),最终达到心肌保护效果.同时现有的研究发现,吸人性麻醉药同样可以诱导产生内源性的心肌保护作用,其作用机制及临床应用前景成为目前广泛关注的焦点,现就以七氟醚为代表的吸入性麻醉药的心肌保护作用及糖尿病与吸人性麻醉药心肌保护作用的关系作一简要综述.

  6. Infiltration anesthetic lidocaine inhibits cancer cell invasion by modulating ectodomain shedding of heparin-binding epidermal growth factor-like growth factor (HB-EGF).

    Science.gov (United States)

    Mammoto, Tadanori; Higashiyama, Shigeki; Mukai, Mutsuko; Mammoto, Akiko; Ayaki, Masako; Mashimo, Takashi; Hayashi, Yukio; Kishi, Yoshihiko; Nakamura, Hiroyuki; Akedo, Hitoshi

    2002-09-01

    Although the mechanism is unknown, infiltration anesthetics are believed to have membrane-stabilizing action. We report here that such a most commonly used anesthetic, lidocaine, effectively inhibited the invasive ability of human cancer (HT1080, HOS, and RPMI-7951) cells at concentrations used in surgical operations (5-20 mM). Ectodomain shedding of heparin-binding epidermal growth factor-like growth factor (HB-EGF) from the cell surface plays an important role in invasion by HT1080 cells. Lidocaine reduced the invasion ability of these cells by partly inhibiting the shedding of HB-EGF from the cell surface and modulation of intracellular Ca2+ concentration contributed to this action. The anesthetic action of lidocaine (sodium channel blocking ability) did not contribute to this anti-invasive action. In addition, lidocaine (5-30 mM), infiltrated around the inoculation site, inhibited pulmonary metastases of murine osteosarcoma (LM 8) cells in vivo. These data point to previously unrecognized beneficial actions of lidocaine and suggest that lidocaine might be an ideal infiltration anesthetic for surgical cancer operations.

  7. [New anesthetics].

    Science.gov (United States)

    Malamed, S F

    2000-01-01

    Since the introduction of cocaine local analgesia in 1886, and the subsequent development of procaine (1904) and other closely related ester-type compounds, dentistry has prided itself on being as close to 'painless' as possible. In the late 1940s the newest group of the local anesthetic compounds, the amides, was introduced. The initial amide local analgesic, lignocaine (Xylocaine), revolutionised pain control in dentistry worldwide. In succeeding years other amide-type local anesthetics, mepivacaine, prilocaine, bupivacaine and etidocaine, were introduced. They gave the dental practitioner a local anesthetic armamentarium which provided pulpal analgesia for periods of from 20 minutes (mepivacaine) to as long as three hours (bupivacaine and etidocaine with adrenaline). In addition these popular drugs proved to be more rapid-acting than the older ester-type drug and, at least from the perspective of allergenicity, more safe. In 1976, in Germany, the newest amide local analgesic, carticaine HCl was introduced into dentistry. Articaine (the generic name was changed) possesses properties similar to lignocaine but has additional properties which made the drug quite attractive to the general dental practitioner. In 1986 articaine was introduced in North America (Canada) where it has become the most used local anesthetic, supplanting lignocaine. Articaine has been approved for use in the United Kingdom. In this introductory discussion we review the development of articaine and discuss its place in the dental local analgesic armamentarium.

  8. Potent Inhalational Anesthetics for Dentistry.

    Science.gov (United States)

    Satuito, Mary; Tom, James

    2016-01-01

    Nitrous oxide and the volatile inhalational anesthetics have defined anxiety and pain control in both dentistry and medicine for over a century. From curious experimentation to spectacular public demonstrations, the initial work of 2 dentists, Horace Wells and William T. G. Morton, persists to this day in modern surgery and anesthesia. This article reviews the history, similarities, differences, and clinical applications of the most popular inhalational agents used in contemporary dental surgical settings.

  9. Functional characterization of a pheromone-binding protein from rice leaffolder Cnaphalocrocis medinalis in detecting pheromones and host plant volatiles.

    Science.gov (United States)

    Sun, X; Zhao, Z-F; Zeng, F-F; Zhang, A; Lu, Z-X; Wang, M-Q

    2016-12-01

    Pheromone-binding proteins (PBPs) are believed to be involved in the recognition of semiochemicals. In the present study, western blot analysis, fluorescence-binding characteristics and immunolocalization of CmedPBP4 from the rice leaffolder, Cnaphalocrocis medinalis, were investigated. Western blot analysis revealed that CmedPBP4 showed obvious antenna-specific expression patterns in female and male antenna, and made a clearly different sex-biased expression. Immunocytochemical labeling revealed that CmedPBP4 showed specific expression in the trichoid sensilla. Competitive fluorescence binding assays indicated that CmedPBP4 could selectively recognize three sex pheromone components (Z13-18:Ac, Z11-16:Al and Z13-18:OH) and eleven rice plant volatiles, including cyclohexanol, nerolidol, cedrol, dodecanal, ionone, (-)-α-cedrene, (Z)-farnesene, β-myrcene, R-(+)-limonene, (-)-limonene, and (+)-3-carene. Meanwhile the CmedPBP4 detection of sex pheromones and host odorants was pH-dependent. Our results, for the first time, provide further evidence that trichoid sensilla might be play an important role in detecting sex pheromones and host plant volatiles in the C. medinalis moth. Our systematic studies provided further detailed evidence for the function of trichoid sensilla in insect semiochemical perception.

  10. Effect of buprenorphine on total intravenous anesthetic requirements during spine surgery.

    Science.gov (United States)

    Khelemsky, Yury; Schauer, Jacob; Loo, Nathaniel

    2015-01-01

    Buprenorphine is a partial mu receptor agonist and kappa/delta antagonist commonly used for the treatment of opioid dependence or as an analgesic. It has a long plasma half-life and a high binding affinity for opioid receptors. This affinity is so high, that the effects are not easily antagonized by competitive antagonists, such as naloxone. The high affinity also prevents binding of other opioids, at commonly used clinical doses, to receptor sites - preventing their analgesic and likely minimum alveolar concentration (MAC) reducing benefits. This case report contrasts the anesthetic requirements of a patient undergoing emergency cervical spine surgery while taking buprenorphine with anesthetic requirements of the same patient undergoing a similar procedure after weaning of buprenorphine. Use of intraoperative neurophysiological monitoring prevented use of paralytics and inhalational anesthetics during both cases, therefore total intravenous anesthesia (TIVA) was maintained with propofol and remifentanil infusions. During the initial surgery, intraoperative patient movement could not be controlled with very high doses of propofol and remifentanil. The patient stopped moving in response to surgical stimulation only after the addition of a ketamine. Buprenorphine-naloxone was discontinued postoperatively. Five days later the patient underwent a similar cervical spine surgery. She had drastically reduced anesthetic requirements during this case, suggesting buprenorphine's profound effect on anesthetic dosing. This case report elegantly illustrates that discontinuation of buprenorphine is likely warranted for patients who present for major spine surgery, which necessitates the avoidance of volatile anesthetic and paralytic agents. The addition of ketamine may be necessary in patients maintained on buprenorphine in order to ensure a motionless surgical field.

  11. Anesthetic Management of a Child with Mitochondrial Neurogastrointestinal Encephalopathy

    Science.gov (United States)

    Casarez, Vianey Q.; Zavala, Acsa M.; Owusu-Agyemang, Pascal; Hagan, Katherine

    2015-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disorder associated with deficiency of thymidine phosphorylase (TP). Associated manifestations include visual and hearing impairments, peripheral neuropathies, leukoencephalopathy, and malnutrition from concomitant gastrointestinal dysmotility and pseudoobstruction. Given the altered metabolic state in these patients, specific consideration of medication selection is advised. This case report will describe the anesthetic management used in a 10-year-old girl with MNGIE. She had multiple anesthetics while undergoing allogeneic hematopoietic stem cell transplantation. This case report will discuss the successful repeated use of the same anesthetic in this pediatric patient, with the avoidance of volatile anesthetic agents, propofol, and muscle relaxant. PMID:26124966

  12. Anesthetic Management of a Child with Mitochondrial Neurogastrointestinal Encephalopathy

    Directory of Open Access Journals (Sweden)

    Vianey Q. Casarez

    2015-01-01

    Full Text Available Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE is an autosomal recessive disorder associated with deficiency of thymidine phosphorylase (TP. Associated manifestations include visual and hearing impairments, peripheral neuropathies, leukoencephalopathy, and malnutrition from concomitant gastrointestinal dysmotility and pseudoobstruction. Given the altered metabolic state in these patients, specific consideration of medication selection is advised. This case report will describe the anesthetic management used in a 10-year-old girl with MNGIE. She had multiple anesthetics while undergoing allogeneic hematopoietic stem cell transplantation. This case report will discuss the successful repeated use of the same anesthetic in this pediatric patient, with the avoidance of volatile anesthetic agents, propofol, and muscle relaxant.

  13. Anesthetic Related Advances with Cyclodextrins

    OpenAIRE

    Mark Welliver; John P. McDonough

    2007-01-01

    Cyclodextrins encapsulate and electrostatically bind to lipophilic molecules. The exterior of cyclodextrins are water-soluble and maintain aqueous solubility despite encapsulation of non-aqueous soluble molecules. This unique ability to encapsulate lipophilic molecules and maintain water solubility confers numerous pharmacologic advantages for both drug delivery and removal. Cyclodextrins, a component part of supramolecular chemistry, may be in its infancy of anesthetic application but recent...

  14. Sevoflurane: a new inhalational anesthetic agent.

    Science.gov (United States)

    Wallin, R F; Regan, B M; Napoli, M D; Stern, I J

    1975-01-01

    Laboratory screening of a series of halogenated methyl isopropyl ethers revealed sevoflurane (fluoromethyl-1,1,1,3,3,3,-hexafluroro-2-propyl ether) as a potent nonexplosive inhalational anesthetic agent. Sevoflurance, a pleasant-smelling liquid, boils at 58.5 degrees C at 760 torr and has a vapor pressure of 200 torr at 25 degrees C. It is nonflammable in air and has lower flammability limits of 11 vols percent in O2 and 10 vols percent in N2O. Sevoflurane exhibits limited chemical reactivity in vitro; it is subject to slight but measurable hydrolysis, and reacts with soda lime to form traces of related ethers. It provides rapid anesthetic induction and recovery consistent with its low distribution coefficients (blood:gas, 0.6; corn oil:gas, 41.6; olive oil:gas, 53.4). In dogs, anesthetic concentrations of sevoflurane did not produce spontaneous cardiac arrhythmias and did not sensitize the heart to epinephrine. Electroencephalographic patterns were similar to those observed during anesthesia with halothane. In rats, small increases in the urinary excretion of inorganic fluoride ion occurred during the first 24 hours after anesthesia. Subacute studies in dogs and rats, using closed-circle absorption with soda lime, revealed no toxicologically significant changes in animals anesthetized frequently for 2 weeks. Sevoflurane appears to be a unique volatile anesthetic agent worthy of further study.

  15. Anesthetic related advances with cyclodextrins.

    Science.gov (United States)

    Welliver, Mark; McDonough, John

    2007-03-02

    Cyclodextrins encapsulate and electrostatically bind to lipophilic molecules. The exterior of cyclodextrins are water-soluble and maintain aqueous solubility despite encapsulation of non-aqueous soluble molecules. This unique ability to encapsulate lipophilic molecules and maintain water solubility confers numerous pharmacologic advantages for both drug delivery and removal. Cyclodextrins, a component part of supramolecular chemistry, may be in its infancy of anesthetic application but recent advances have been described as novel and revolutionary. A review of current research coupled with an understanding of cyclodextrin properties is necessary to fully appreciate the current uses and future potentials of these unique molecules.

  16. Anesthetic Related Advances with Cyclodextrins

    Directory of Open Access Journals (Sweden)

    Mark Welliver

    2007-01-01

    Full Text Available Cyclodextrins encapsulate and electrostatically bind to lipophilic molecules. The exterior of cyclodextrins are water-soluble and maintain aqueous solubility despite encapsulation of non-aqueous soluble molecules. This unique ability to encapsulate lipophilic molecules and maintain water solubility confers numerous pharmacologic advantages for both drug delivery and removal. Cyclodextrins, a component part of supramolecular chemistry, may be in its infancy of anesthetic application but recent advances have been described as novel and revolutionary. A review of current research coupled with an understanding of cyclodextrin properties is necessary to fully appreciate the current uses and future potentials of these unique molecules.

  17. Anesthetizing the obese child

    DEFF Research Database (Denmark)

    Mortensen, Anette; Lenz, Katja; Abildstrøm, Hanne

    2011-01-01

    The prevalence of childhood obesity is increasing. The focus of this review is the special anesthetic considerations regarding the perioperative management of obese children. With obesity the risk of comorbidity such as asthma, obstructive sleep apnea, hypertension, and diabetes increases....... The obese child has an increased risk of perioperative complications especially related to airway management and ventilation. There is a significantly increased risk of difficult mask ventilation and perioperative desaturation. Furthermore, obesity has an impact on the pharmacokinetics of most anesthetic...

  18. Identification of Host-Plant Volatiles and Characterization of Two Novel General Odorant-Binding Proteins from the Legume Pod Borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae).

    Science.gov (United States)

    Zhou, Jing; Zhang, Na; Wang, Pan; Zhang, Shichang; Li, Daiqin; Liu, Kaiyu; Wang, Guoxiu; Wang, Xiaoping; Ai, Hui

    2015-01-01

    Chemoreception is a key feature in selection of host plant by phytophagous insects, and odorant-binding proteins (OBPs) are involved in chemical communication of both insects and vertebrates. The legume pod borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae) is one of the key pest species of cowpea and widely distributed throughout tropical and subtropical regions, causing up to 80% of yield loss. In this study, we investigated the electrophysiological responses of female M. vitrata to floral volatiles from V. unguiculata. Seventeen electroantennogram-active compounds were identified from floral volatiles of V. unguiculata by coupled gas chromatography-electroantennography (GC-EAD) and gas chromatography-mass spectrometry (GC-MS). Then, we cloned two novel full-length GOBP genes (MvitGOBP1 and MvitGOBP2) from the antennae of M. vitrata using reverse transcription PCR. Protein sequence analysis indicated that they shared high sequence similarity with other Pyralididae insect GOBPs and had the typical six-cysteine signature. Real-time PCR analysis indicated that MvitGOBP1-2 mRNA was highly expressed in the antennae of female adult with several thousands-fold difference compare to other tissue. Next, the recombinant MvitGOBP1-2 was expressed in Escherichia coli and purified using Ni ion affinity chromatography. Fluorescence binding assays demonstrated that MvitGOBP1-2 had different binding affinities with 17 volatile odorant molecules including butanoic acid butyl ester, limonene, 4-ethylpropiophenone, 1H-indol-4-ol, butanoic acid octyl ester and 2-methyl-3-phenylpropanal. In the field trapping experiment, these six floral volatiles could effectively attract female moths and showed significant difference compared with the blank lure. These results suggested that MvitGOBPs and the seventeen floral volatiles are likely to function in the olfactory behavior response of female moths, which may have played crucial roles in the selection of oviposition sites. The six

  19. Identification of Host-Plant Volatiles and Characterization of Two Novel General Odorant-Binding Proteins from the Legume Pod Borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae.

    Directory of Open Access Journals (Sweden)

    Jing Zhou

    Full Text Available Chemoreception is a key feature in selection of host plant by phytophagous insects, and odorant-binding proteins (OBPs are involved in chemical communication of both insects and vertebrates. The legume pod borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae is one of the key pest species of cowpea and widely distributed throughout tropical and subtropical regions, causing up to 80% of yield loss. In this study, we investigated the electrophysiological responses of female M. vitrata to floral volatiles from V. unguiculata. Seventeen electroantennogram-active compounds were identified from floral volatiles of V. unguiculata by coupled gas chromatography-electroantennography (GC-EAD and gas chromatography-mass spectrometry (GC-MS. Then, we cloned two novel full-length GOBP genes (MvitGOBP1 and MvitGOBP2 from the antennae of M. vitrata using reverse transcription PCR. Protein sequence analysis indicated that they shared high sequence similarity with other Pyralididae insect GOBPs and had the typical six-cysteine signature. Real-time PCR analysis indicated that MvitGOBP1-2 mRNA was highly expressed in the antennae of female adult with several thousands-fold difference compare to other tissue. Next, the recombinant MvitGOBP1-2 was expressed in Escherichia coli and purified using Ni ion affinity chromatography. Fluorescence binding assays demonstrated that MvitGOBP1-2 had different binding affinities with 17 volatile odorant molecules including butanoic acid butyl ester, limonene, 4-ethylpropiophenone, 1H-indol-4-ol, butanoic acid octyl ester and 2-methyl-3-phenylpropanal. In the field trapping experiment, these six floral volatiles could effectively attract female moths and showed significant difference compared with the blank lure. These results suggested that MvitGOBPs and the seventeen floral volatiles are likely to function in the olfactory behavior response of female moths, which may have played crucial roles in the selection of oviposition

  20. Fluorescence competition assay for the assessment of green leaf volatiles and trans-β-farnesene bound to three odorant-binding proteins in the wheat aphid Sitobion avenae (Fabricius).

    Science.gov (United States)

    Zhong, Tao; Yin, Jiao; Deng, Sisi; Li, Kebin; Cao, Yazhong

    2012-06-01

    Odorant-binding proteins (OBPs) are important parts of insect olfactory systems, and sensitive olfaction is vital for phytophagous insects in host foraging. Electrophysiological studies are helpful in understanding olfactory sensing in Sitobion avenae (Hemiptera: Aphididae), but the functions of odorant-binding proteins in this insect are poorly understood. In this study, we used fluorescence competition assays to measure the binding specificities of SaveOBPs. The results showed that both SaveOBP2 and SaveOBP3 were superior to SaveOBP7 in binding green leaf volatiles. It was unexpected that SaveOBP7 bound trans-β-farnesene strongly, which was known as alarm pheromone of this species. Host volatiles were recognized much more easily by SaveOBP2, and the observed binding activity of SaveOBP2 equaled for tested green leaf volatiles. Our results imply that SaveOBP7 might play a more important role in aphid alarm pheromone discrimination.

  1. In vivo binding, pharmacokinetics and metabolism of the selective M{sub 2} muscarinic antagonists [{sup 3}H]AF-DX 116 and [{sup 3}H]AF-DX 384 in the anesthetized rat

    Energy Technology Data Exchange (ETDEWEB)

    Mickala, Patrick; Boutin, Herve; Bellanger, Cecile; Chevalier, Cyril; MacKenzie, Eric T.; Dauphin, Francois

    1996-02-01

    The pharmacokinetics, in vivo binding and metabolism of two M{sub 2} muscarinic receptor antagonists, [{sup 3}H]AF-DX 116 and [{sup 3}H]AF-DX 384, were studied in anesthetized rats, which received either the tracer alone or following a saturating injection of atropine. Both radioligands were cleared from the circulation with distribution half-lives of 17 and 14 sec and elimination half-lives of 17 and 40 min for [{sup 3}H]AF-DX 116 and [{sup 3}H]AF-DX 384, respectively. A radioactive distribution, predominant in peripheral organs when compared to brain, was found at each time studied after tracer injection. Atropine-displaceable tracer uptake was evidenced at 20-40 min in brain (31%), submandibular glands (26%), spleen (37%) and notably heart (55%) for [{sup 3}H]AF-DX 116 but only in heart (50%) for [{sup 3}H]AF-DX 384 at 10-20 min. Regional brain sampling revealed a relatively uniform distribution of [{sup 3}H]AF-DX 384 and a -45% atropine saturation effect (i.e., specific binding) in the thalamus 20 min after injection. Sequential thin-layer chromatographic studies performed on tissue extracts demonstrated the rapid appearance of labeled metabolites of both radiotracers in brain (but less so in liver) and especially in cardiac tissues, where almost 70% of total radioactivity still corresponded to authentic tracer 40 min after injection. Thus, based on their low blood-brain barrier permeability and the high presence of labeled metabolites in the central nervous system, AF-DX 116 and AF-DX 384 might be more helpful in the study of M{sub 2} muscarinic receptors present in heart rather than brain. Labeled with positron emittors, these M{sub 2} antagonists might be applicable to the pathophysiological study of disease states, such as cardiomyopathies.

  2. Anesthetic Considerations in a Patient with Myotonic Dystrophy for Hip Labral Repair

    Science.gov (United States)

    Wang, David; Ludwin, Danielle

    2017-01-01

    Myotonic Dystrophy (DM) affects multiple organ systems. Disorders such as hyperthyroidism, progressive musculoskeletal weakness, cardiac dysrhythmias, hypoventilation, and cognitive-behavioral disorders may be present in these patients. Thorough preoperative assessment and anesthetic planning are required to minimize the risk of anesthetic complications. Patients with DM can exhibit exquisite sensitivity to sedatives, neuromuscular blocking agents, and volatile anesthetics, resulting in potential postoperative complications. There is limited literature available on successful anesthetic techniques for the DM patient. We present this case report to add to our current fund of knowledge. PMID:28316843

  3. Virtual Screening of Plant Volatile Compounds Reveals a High Affinity of Hylamorpha elegans (Coleoptera: Scarabaeidae) Odorant-Binding Proteins for Sesquiterpenes From Its Native Host

    Science.gov (United States)

    Palma-Millanao, Rubén; Yáñez, Osvaldo; Rojas, Maximiliano; Mutis, Ana; Venthur, Herbert; Quiroz, Andrés; Ramírez, Claudio C.

    2016-01-01

    Hylamorpha elegans (Burmeister) is a native Chilean scarab beetle considered to be a relevant agricultural pest to pasture and cereal and small fruit crops. Because of their cryptic habits, control with conventional methods is difficult; therefore, alternative and environmentally friendly control strategies are highly desirable. The study of proteins that participate in the recognition of odorants, such as odorant-binding proteins (OBPs), offers interesting opportunities to identify new compounds with the potential to modify pest behavior and computational screening of compounds, which is commonly used in drug discovery, may help to accelerate the discovery of new semiochemicals. Here, we report the discovery of four OBPs in H. elegans as well as six new volatiles released by its native host Nothofagus obliqua (Mirbel). Molecular docking performed between OBPs and new and previously reported volatiles from N. obliqua revealed the best binding energy values for sesquiterpenic compounds. Despite remarkable divergence at the amino acid level, three of the four OBPs evaluated exhibited the best interaction energy for the same ligands. Molecular dynamics investigation reinforced the importance of sesquiterpenes, showing that hydrophobic residues of the OBPs interacted most frequently with the tested ligands, and binding free energy calculations demonstrated van der Waals and hydrophobic interactions to be the most important. Altogether, the results suggest that sesquiterpenes are interesting candidates for in vitro and in vivo assays to assess their potential application in pest management strategies. PMID:27012867

  4. Virtual Screening of Plant Volatile Compounds Reveals a High Affinity of Hylamorpha elegans (Coleoptera: Scarabaeidae) Odorant-Binding Proteins for Sesquiterpenes From Its Native Host.

    Science.gov (United States)

    González-González, Angélica; Palma-Millanao, Rubén; Yáñez, Osvaldo; Rojas, Maximiliano; Mutis, Ana; Venthur, Herbert; Quiroz, Andrés; Ramírez, Claudio C

    2016-01-01

    Hylamorpha elegans(Burmeister) is a native Chilean scarab beetle considered to be a relevant agricultural pest to pasture and cereal and small fruit crops. Because of their cryptic habits, control with conventional methods is difficult; therefore, alternative and environmentally friendly control strategies are highly desirable. The study of proteins that participate in the recognition of odorants, such as odorant-binding proteins (OBPs), offers interesting opportunities to identify new compounds with the potential to modify pest behavior and computational screening of compounds, which is commonly used in drug discovery, may help to accelerate the discovery of new semiochemicals. Here, we report the discovery of four OBPs inH. elegans as well as six new volatiles released by its native host Nothofagus obliqua(Mirbel). Molecular docking performed between OBPs and new and previously reported volatiles from N. oblique revealed the best binding energy values for sesquiterpenic compounds. Despite remarkable divergence at the amino acid level, three of the four OBPs evaluated exhibited the best interaction energy for the same ligands. Molecular dynamics investigation reinforced the importance of sesquiterpenes, showing that hydrophobic residues of the OBPs interacted most frequently with the tested ligands, and binding free energy calculations demonstrated van der Waals and hydrophobic interactions to be the most important. Altogether, the results suggest that sesquiterpenes are interesting candidates for in vitro and in vivo assays to assess their potential application in pest management strategies.

  5. Anesthetic management of ostriches.

    Science.gov (United States)

    Cornick, J L; Jensen, J

    1992-06-01

    We evaluated and characterized several anesthetic induction protocols used to facilitate intubation and anesthetic maintenance with isoflurane in 7 adult ostriches and 1 juvenile ostrich. Induction protocols included IV administration of zolazepam/tiletamine, IV administration of diazepam/ketamine with and without xylazine, IV administration of xylazine/ketamine, IM administration of carfentanil or xylazine/carfentanil, and mask induction with isoflurane. General anesthesia was maintained with isoflurane in 100% oxygen for various procedures, including proventriculotomy (6 birds), tibial (1 bird) or mandibular (1 bird) fracture repair, and drainage of an iatrogenic hematoma (1 bird). Heart rate and respiratory rate varied greatly among birds. The arterial blood pressure values recorded from 6 of the birds during maintenance of general anesthesia were higher than values recorded for most mammalian species, but were comparable to values reported for awake chickens and turkeys.

  6. Effect of local anesthetics on serotonin1A receptor function.

    Science.gov (United States)

    Rao, Bhagyashree D; Shrivastava, Sandeep; Chattopadhyay, Amitabha

    2016-12-01

    The fundamental mechanism behind the action of local anesthetics is still not clearly understood. Phenylethanol (PEtOH) is a constituent of essential oils with a pleasant odor and can act as a local anesthetic. In this work, we have explored the effect of PEtOH on the function of the hippocampal serotonin1A receptor, a representative neurotransmitter receptor belonging to the G protein-coupled receptor (GPCR) family. Our results show that PEtOH induces reduction in ligand binding to the serotonin1A receptor due to lowering of binding affinity, along with a concomitant decrease in the degree of G-protein coupling. Analysis of membrane order using the environment-sensitive fluorescent probe DPH revealed decrease in membrane order with increasing PEtOH concentration, as evident from reduction in rotational correlation time of the probe. Analysis of results obtained shows that the action of local anesthetics could be attributed to the combined effects of specific interaction of the receptor with anesthetics and alteration of membrane properties (such as membrane order). These results assume relevance in the perspective of anesthetic action and could be helpful to achieve a better understanding of the possible role of anesthetics in the function of membrane receptors.

  7. Anesthetics drug pharmacodynamics.

    Science.gov (United States)

    Bischoff, P; Schneider, G; Kochs, E

    2008-01-01

    Anesthesia cannot be defined in an unambiguous manner. The essential components of general anesthesia are absence of consciousness and pain. This translates into two particular qualities: (1) sedation and hypnosis, i.e., mental blockade and (2) analgesia/antinociception, i.e., sensory blockade. Anesthetic actions on these two subcomponents are difficult to separate. On the one hand, very few anesthetics act exclusively on one of these components. On the other hand, these components are closely related to each other. Unconsciousness prevents (conscious) perception of pain, and nociception may serve as an arousal stimulus and change the level of sedation and hypnosis. The art of anesthesia lies in adequate dosing of drugs to reach both mental and sensory blockade. Drug administration can be based on pharmacokinetic considerations. Pharmacokinetic models allow an estimation of what happens to the administered drug in the body. Models with an effect site compartment may facilitate a tailored administration of anesthetic drugs. Finally, the quantification of pharmacodynamic effects allows a precise titration of drugs. Clinical assessment of mental blockade is often dichotomous, and therefore not very helpful to guide drug administration. Several scoring systems exist, but once consciousness is lost they become less reliable, in particular because reaction to stimuli is assessed, which mixes assessment of mental blockade with assessment of sensory blockade. Clinical assessment of analgesia requires a conscious patient, so antinociception is difficult to measure. Several methods of objective quantification on the basis of electrical brain activity are discussed including EEG and evoked potentials. Despite numerous indexes of the hypnotic component of anesthesia, there is no parameter that unambiguously quantifies the level of mental or sensory blockade.

  8. Anesthetic-Induced Developmental Neurotoxicity

    Institute of Scientific and Technical Information of China (English)

    Jia-RenLiu; Qian Liu; Jing Li; Sulpicio G. Soriano

    2011-01-01

    1 IntroductionMillions of newborn and infants receive anesthetic,sedative and analgesic drugs for surgery and painful procedures on a daily basis.Recent laboratory reports clearly demonstrate that anesthetic and sedative drugs induced both neuroapoptosis and neurocognitive deficits in laboratory models.This issue is of paramount interest to pediatric anesthesiologists and intensivists because it questions the safety of anesthetics used for fetal and neonatal anesthesia[1-2].In an attempt to summarize the rapidly expanding laboratorybased literature on anesthetic-induced developmental neurotoxicity (AIDN),this review will examine published reports on the characterization,mechanisms and alleviation of this phenomenon.

  9. Llama anesthetic programs.

    Science.gov (United States)

    Heath, R B

    1989-03-01

    Llamas are anesthetized conveniently with guaifenesin thiamylal mixes, or, for short periods of time, with xylazine/ketamine. Small individuals must be accurately weighed. Estimating weight without experience is dangerous in this species. The greatest levels of safety and control, especially for critical patients, is afforded by inhalation anesthesia techniques using small animal equipment. All neonates and juveniles can be masked readily but in adults intravenous induction is most satisfactory. Intubation is aided by a long blade laryngoscope. Blood pressure monitoring is best accomplished with an arterial line in the ear artery. However, doppler equipment on the tail or distal leg usually works well.

  10. Dexmedetomidine as the primary anesthetic agent during cardiac surgery in an infant with a family history of malignant hyperthermia

    Directory of Open Access Journals (Sweden)

    Aymen Naguib

    2011-01-01

    Full Text Available Malignant hyperthermia (MH is an acute hypermetabolic crisis triggered in susceptible patients by the administration of succinylcholine or a volatile anesthetic agent. When providing anesthetic care for MH-susceptible agents, a total intravenous anesthetic (TIVA technique is frequently chosen. When choosing the components for TIVA, several options exist including the combination of propofol or dexmedetomidine with an opioid. We present our experience with the use of dexmedetomidine as a key component of the anesthetic regimen in a 5-month-old infant with a family history of MH. Previous reports of the use of dexmedetomidine in MH-susceptible patients are reviewed and its benefits in such patients discussed.

  11. Plant phenolic volatiles inhibit quorum sensing in pectobacteria and reduce their virulence by potential binding to ExpI and ExpR proteins

    Science.gov (United States)

    Joshi, Janak Raj; Khazanov, Netaly; Senderowitz, Hanoch; Burdman, Saul; Lipsky, Alexander; Yedidia, Iris

    2016-12-01

    Quorum sensing (QS) is a population density-dependent regulatory system in bacteria that couples gene expression to cell density through accumulation of diffusible signaling molecules. Pectobacteria are causal agents of soft rot disease in a range of economically important crops. They rely on QS to coordinate their main virulence factor, production of plant cell wall degrading enzymes (PCWDEs). Plants have evolved an array of antimicrobial compounds to anticipate and cope with pathogens, of which essential oils (EOs) are widely recognized. Here, volatile EOs, carvacrol and eugenol, were shown to specifically interfere with QS, the master regulator of virulence in pectobacteria, resulting in strong inhibition of QS genes, biofilm formation and PCWDEs, thereby leading to impaired infection. Accumulation of the signal molecule N-acylhomoserine lactone declined upon treatment with EOs, suggesting direct interaction of EOs with either homoserine lactone synthase (ExpI) or with the regulatory protein (ExpR). Homology models of both proteins were constructed and docking simulations were performed to test the above hypotheses. The resulting binding modes and docking scores of carvacrol and eugenol support potential binding to ExpI/ExpR, with stronger interactions than previously known inhibitors of both proteins. The results demonstrate the potential involvement of phytochemicals in the control of Pectobacterium.

  12. Local anesthetics: New insights into risks and benefits

    NARCIS (Netherlands)

    Lirk, P.

    2014-01-01

    Conventional local anesthetics in contemporary use block the voltage-gated sodium channel by binding to a specific site on the inner facet of the channel pore. Only little fractions of local anaesthetic are thought to participate in nerve blockade, the rest is absorbed into surrounding tissues or th

  13. Anesthetics interacting with lipid rafts.

    Science.gov (United States)

    Bandeiras, Cátia; Serro, Ana Paula; Luzyanin, Konstantin; Fernandes, Anabela; Saramago, Benilde

    2013-01-23

    The exact mechanism by which anesthetics induce cell membrane-mediated modifications is still an open question. Although the fluidization effect of the anesthetic molecules on the cellular membrane is widely recognized, it is not known if anesthetics show any preference for specific membrane domains, namely the lipid rafts. The importance of these membrane micro-domains derives from the fact that they have been associated with cell signaling pathways, as well as with specific drug interactions. The objective of this work is to contribute for the elucidation of this question through the comparison of the anesthetic interactions with membranes of various lipid compositions. Liposomes prepared with an equimolar mixture of POPC, sphingomyelin and cholesterol, were chosen as models for lipid rafts. The interactions of these liposomes with two local anesthetics, tetracaine and lidocaine, and one general anesthetic, propofol, were studied. The effect of cholesterol was investigated by comparing anesthetic interactions with POPC/SM liposomes and POPC/SM/CHOL liposomes. The following experimental techniques were used: quartz crystal microbalance with dissipation, differential scanning calorimetry and phosphorus nuclear magnetic resonance. Although the liposomes investigated by the different techniques are not in the same conditions, it is possible to assemble the information obtained from all experimental techniques employed to reach a general conclusion. Tetracaine interacts more with raftlike domains, lidocaine induces stronger modifications on POPC/SM liposomes and the results for propofol are not fully conclusive but it seems to be the least prone to lipid interactions. The results were compared with those obtained with DMPC-containing liposomes, reported in a previous work.

  14. Nitrogen narcosis and pressure reversal of anesthetic effects in node of Ranvier.

    Science.gov (United States)

    Kendig, J J

    1984-01-01

    To compare sodium channel block by hyperbaric nitrogen with that induced by other anesthetics and to examine the basis for pressure antagonism to anesthetic condition block, voltage clamped nodes of Ranvier were exposed to nitrogen at pressures at 1-14 atm alone and in combination with helium to a total pressure of up to 100 atm. At 7 and 14 atm nitrogen, sodium currents were reversibly depressed without accompanying changes in the current-voltage relation. The curve relating steady-state inactivation (h infinity) to voltage was shifted in the hyperpolarizing direction, as is the case with other general anesthetic agents. The time constant of inactivation (tau h) was slightly decreased at depolarized potentials. The preceding companion paper demonstrated an opposite effect of hyperbaric helium on the properties of sodium inactivation. Addition of helium pressure in the presence of nitrogen at 14 atm did not increase peak sodium current with inactivation maximally removed, but it did shift the h infinity curve back toward control levels, thus increasing sodium current at points on the slope of the curve. It is proposed that these opposing shifts in steady-state inactivation levels are the basis for pressure antagonism to anesthetic conduction block. In the case of inert gases and volatile anesthetic agents, the antagonism may be direct but has not been shown to be so. In the case of the local anesthetic benzocaine, differences in the voltage dependence of anesthetic and pressure-induced changes in tau h indicate the antagonism is indirect.

  15. Volatility Discovery

    DEFF Research Database (Denmark)

    Dias, Gustavo Fruet; Scherrer, Cristina; Papailias, Fotis

    The price discovery literature investigates how homogenous securities traded on different markets incorporate information into prices. We take this literature one step further and investigate how these markets contribute to stochastic volatility (volatility discovery). We formally show...... that the realized measures from homogenous securities share a fractional stochastic trend, which is a combination of the price and volatility discovery measures. Furthermore, we show that volatility discovery is associated with the way that market participants process information arrival (market sensitivity...

  16. Volatile Metabolites

    Directory of Open Access Journals (Sweden)

    Daryl D. Rowan

    2011-11-01

    Full Text Available Volatile organic compounds (volatiles comprise a chemically diverse class of low molecular weight organic compounds having an appreciable vapor pressure under ambient conditions. Volatiles produced by plants attract pollinators and seed dispersers, and provide defense against pests and pathogens. For insects, volatiles may act as pheromones directing social behavior or as cues for finding hosts or prey. For humans, volatiles are important as flavorants and as possible disease biomarkers. The marine environment is also a major source of halogenated and sulfur-containing volatiles which participate in the global cycling of these elements. While volatile analysis commonly measures a rather restricted set of analytes, the diverse and extreme physical properties of volatiles provide unique analytical challenges. Volatiles constitute only a small proportion of the total number of metabolites produced by living organisms, however, because of their roles as signaling molecules (semiochemicals both within and between organisms, accurately measuring and determining the roles of these compounds is crucial to an integrated understanding of living systems. This review summarizes recent developments in volatile research from a metabolomics perspective with a focus on the role of recent technical innovation in developing new areas of volatile research and expanding the range of ecological interactions which may be mediated by volatile organic metabolites.

  17. Multiple anesthetics for a patient with stiff-person syndrome.

    Science.gov (United States)

    Cassavaugh, Jessica M; Oravitz, Todd M

    2016-06-01

    Stiff-person syndrome is a progressive disease of muscle rigidity and spasticity due to a deficiency in the production of γ-aminobutyric acid. Because of the rarity of the condition, little is known about effects of anesthesia on patients with stiff-person syndrome. This report describes the clinical course for a single patient with stiff-person syndrome who received general anesthesia on 3 separate occasions. Her anesthetics included use of both neuromuscular blockade and volatile agents. Unlike several previous reports regarding anesthesia and stiff-person syndrome, the postoperative period for this patient did not require prolonged intubation or result in any residual weakness.

  18. Genotoxicity of Anesthetics Evaluated In Vivo (Animals)

    Science.gov (United States)

    Braz, Mariana G.; Karahalil, Bensu

    2015-01-01

    The anesthesia has been improved all over the years. However, it can have impact on health, in both patients and animals anesthetized, as well as professionals exposed to inhaled anesthetics. There is continuing effort to understand the possible effects of anesthetics at molecular levels. Knowing the effects of anesthetic agents on genetic material could be a valuable basic support to better understand the possible mechanisms of these agents. Thus, the purpose of this review is to provide an overview on the genotoxic potential, evaluated in animal models, of many anesthetics that have already been used and those currently used in anesthesia. PMID:26199936

  19. Plant volatiles.

    Science.gov (United States)

    Baldwin, Ian T

    2010-05-11

    Plant volatiles are the metabolites that plants release into the air. The quantities released are not trivial. Almost one-fifth of the atmospheric CO2 fixed by land plants is released back into the air each day as volatiles. Plants are champion synthetic chemists; they take advantage of their anabolic prowess to produce volatiles, which they use to protect themselves against biotic and abiotic stresses and to provide information - and potentially disinformation - to mutualists and competitors alike. As transferors of information, volatiles have provided plants with solutions to the challenges associated with being rooted in the ground and immobile.

  20. Unstable volatility

    DEFF Research Database (Denmark)

    Casas, Isabel; Gijbels, Irène

    2012-01-01

    The objective of this paper is to introduce the break-preserving local linear (BPLL) estimator for the estimation of unstable volatility functions for independent and asymptotically independent processes. Breaks in the structure of the conditional mean and/or the volatility functions are common i...

  1. Anesthetic gases and global warming: Potentials, prevention and future of anesthesia.

    Science.gov (United States)

    Gadani, Hina; Vyas, Arun

    2011-01-01

    Global warming refers to an average increase in the earth's temperature, which in turn causes changes in climate. A warmer earth may lead to changes in rainfall patterns, a rise in sea level, and a wide range of impacts on plants, wildlife, and humans. Greenhouse gases make the earth warmer by trapping energy inside the atmosphere. Greenhouse gases are any gas that absorbs infrared radiation in the atmosphere and include: water vapor, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), halogenated fluorocarbons (HCFCs), ozone (O3), perfluorinated carbons (PFCs), and hydrofluorocarbons (HFCs). Hazardous chemicals enter the air we breathe as a result of dozens of activities carried out during a typical day at a healthcare facility like processing lab samples, burning fossil fuels etc. We sometimes forget that anesthetic agents are also greenhouse gases (GHGs). Anesthetic agents used today are volatile halogenated ethers and the common carrier gas nitrous oxide known to be aggressive GHGs. With less than 5% of the total delivered halogenated anesthetic being metabolized by the patient, the vast majority of the anesthetic is routinely vented to the atmosphere through the operating room scavenging system. The global warming potential (GWP) of a halogenated anesthetic is up to 2,000 times greater than CO2. Global warming potentials are used to compare the strength of different GHGs to trap heat in the atmosphere relative to that of CO2. Here we discuss about the GWP of anesthetic gases, preventive measures to decrease the global warming effects of anesthetic gases and Xenon, a newer anesthetic gas for the future of anesthesia.

  2. Strabismus complications from local anesthetics.

    Science.gov (United States)

    Guyton, David L

    2008-01-01

    Strabismus developing after retrobulbar or peribulbar anesthesia for both anterior and posterior segment eye surgery may be due to myotoxicity to an extraocular muscle from the local anesthetic agent. Initial paresis often causes diplopia immediately after surgery, but later progressive segmental fibrosis occurs, and/or hypertrophy of the muscle, producing diplopia in the opposite direction from the direction of the initial diplopia. The inferior rectus muscle is most commonly affected. Usually a large recession on an adjustable suture of the involved muscle(s) yields good alignment. Using topical anesthesia or sub-Tenon's anesthesia can avoid this complication.

  3. Chasing volatility

    DEFF Research Database (Denmark)

    Caporin, Massimiliano; Rossi, Eduardo; Santucci de Magistris, Paolo

    The realized volatility of financial returns is characterized by persistence and occurrence of unpreditable large increments. To capture those features, we introduce the Multiplicative Error Model with jumps (MEM-J). When a jump component is included in the multiplicative specification, the condi...... models, the introduction of the jump component provides a sensible improvement in the fit, as well as for in-sample and out-of-sample volatility tail forecasts....

  4. Prophylactic Antiarrhythmic Effect of Anesthetics at Subanesthetic Concentration on Epinephrine-Induced Arrhythmias in Rats after Brain Death

    Directory of Open Access Journals (Sweden)

    Yuka Miyata

    2015-01-01

    Full Text Available The present study using brain death model of rats was designed to examine whether prophylactic administration of volatile anesthetics and propofol prevent the epinephrine-induced arrhythmias. A Fogarty catheter was placed intracranially for induction of brain death. After brain death, the rats were randomly assigned to five groups: the control group (no anesthetics, the sevoflurane group (0.8%, the isoflurane group (0.5%, the halothane group (0.3%, and the propofol group (195 μg·kg−1·min−1. These anesthetics were about 30% of ED50 of each anesthetic. The arrhythmogenic dose of epinephrine was determined in each anesthetic group. In addition, we examined left ventricular levels of connexin 43 phosphorylation 30 min after administration of each anesthetic with Western blot analysis. The arrhythmogenic dose of epinephrine in the sevoflurane group was significantly higher than that in the control group, while the arrhythmogenic dose of epinephrine in any other anesthetic group was not different. On the other hand, the ratio of phosphorylated-connexin 43/total connexin 43 was also similar among the study groups. Thus, prophylactic administration of subanesthetic dose of sevoflurane is effective in preventing epinephrine-induced arrhythmias after brain death, but phosphorylation of connexin is not involved in the antiarrhythmic property of sevoflurane.

  5. Prophylactic antiarrhythmic effect of anesthetics at subanesthetic concentration on epinephrine-induced arrhythmias in rats after brain death.

    Science.gov (United States)

    Miyata, Yuka; Iwasaki, Mitsuo; Yamanaka, Hiroo; Sato, Masanori; Kamibayashi, Takahiko; Fujino, Yuji; Hayashi, Yukio

    2015-01-01

    The present study using brain death model of rats was designed to examine whether prophylactic administration of volatile anesthetics and propofol prevent the epinephrine-induced arrhythmias. A Fogarty catheter was placed intracranially for induction of brain death. After brain death, the rats were randomly assigned to five groups: the control group (no anesthetics), the sevoflurane group (0.8%), the isoflurane group (0.5%), the halothane group (0.3%), and the propofol group (195 μg·kg(-1) ·min(-1)). These anesthetics were about 30% of ED50 of each anesthetic. The arrhythmogenic dose of epinephrine was determined in each anesthetic group. In addition, we examined left ventricular levels of connexin 43 phosphorylation 30 min after administration of each anesthetic with Western blot analysis. The arrhythmogenic dose of epinephrine in the sevoflurane group was significantly higher than that in the control group, while the arrhythmogenic dose of epinephrine in any other anesthetic group was not different. On the other hand, the ratio of phosphorylated-connexin 43/total connexin 43 was also similar among the study groups. Thus, prophylactic administration of subanesthetic dose of sevoflurane is effective in preventing epinephrine-induced arrhythmias after brain death, but phosphorylation of connexin is not involved in the antiarrhythmic property of sevoflurane.

  6. Mechanism of Anesthetic Toxicity: Metabolism, Reactive Oxygen Species, Oxidative Stress, and Electron Transfer

    OpenAIRE

    2011-01-01

    There is much literature on the toxic effects of anesthetics. This paper deals with both the volatiles and locals. Adverse effects appear to be multifaceted, with the focus on radicals, oxidative stress (OS), and electron transfer (ET). ET functionalities involved are quinone, iminoquinone, conjugated iminium, and nitrone. The non-ET routes involving radicals and OS apparently pertain to haloalkanes and ethers. Beneficial effects of antioxidants, evidently countering OS, are reported. Knowled...

  7. Functional characterization of a pheromone binding protein from rice leaf-folder cnaphalocrocis medinalis in detecting pheromones and host plant volatiles

    Science.gov (United States)

    Pheromone-binding proteins (PBPs) are believed to be involved in the recognition of semiochemicals. In the present study, western blot analysis, fluorescence binding characteristics, and immunolocalization of the CmedPBP4 from rice leaf-folder, Cnaphalocrocis medinalis, were investigated. The wester...

  8. Anesthetizing animals: Similar to humans yet, peculiar?

    Science.gov (United States)

    Kurdi, Madhuri S; Ramaswamy, Ashwini H

    2015-01-01

    From time immemorial, animals have served as models for humans. Like humans, animals too have to undergo several types of elective and emergency surgeries. Several anesthetic techniques and drugs used in humans are also used in animals. However, unlike humans, the animal kingdom includes a wide variety of species, breeds, and sizes. Different species have variable pharmacological responses, anatomy, temperament, behavior, and lifestyles. The anesthetic techniques and drugs have to suit different species and breeds. Nevertheless, there are several drugs and many peculiar anesthetic techniques used in animals but not in human beings. Keeping this in mind, literature was hand searched and electronically searched using the words "veterinary anesthesia," "anesthetic drugs and techniques in animals" using Google search engine. The interesting information so collected is presented in this article which highlights some challenging and amazing aspects of anesthetizing animals including the preanesthetic assessment, preparation, premedication, monitoring, induction of general anesthesia, intubation, equipment, regional blocks, neuraxial block, and perioperative complications.

  9. Child with aplastic anemia: Anesthetic management

    Directory of Open Access Journals (Sweden)

    Manpreet Kaur

    2012-01-01

    Full Text Available Aplastic anemia is a rare heterogeneous disorder of hematopoietic stem cells causing pancytopenia and marrow hypoplasia with the depletion of all types of blood cells. This results in anemia, neutropenia and thrombocytopenia, which pose a challenge to both surgical and anesthetic management of such cases. We report a child with aplastic anemia who sustained traumatic ulcer on the arm and underwent split-thickness skin grafting under general anesthesia. There are only two case reports on anesthetic considerations in aplastic anemia patients in the literature. The anesthetic management is challenging because of the rarity of the disease, associated pancytopenia and immunosuppression.

  10. LOCAL ANESTHETICS IN PATIENTS WITH CARDIOVASCULAR DISEASES.

    Directory of Open Access Journals (Sweden)

    risto Daskalov

    2015-03-01

    Full Text Available A significant problem in the dental medicine is pain alleviation. Many studies in the dental anesthesiology result in the production of new agents for locoregional anesthesia. Objective: This article aim to present the results of the last studies on the effect of the local anesthetics used in the oral surgery on patients with cardiovascular diseases. Material: A general review of the existing literature on the effect of the adrenaline, included as vasoconstrictor in the local anesthetics, used in patients with cardiovascular diseases is made. The benefits of vasoconstrictors for the quality of the anesthetic effect are proven. Conclusion: A small amount of adrenaline in the anesthetic solution does not result in complications development in patients with controlled cardiovascular diseases. Articaine is recommended agent of first choice for local anesthesia in the oral surgery.

  11. SYSTEMIC TOXIC REACTIONS TO LOCAL ANESTHETICS

    Science.gov (United States)

    Moore, Daniel C.; Green, John

    1956-01-01

    The topical use of anesthetic agents involves an element of risk. Systemic toxic reactions are rare, but they do occur and may result in death. When a reaction occurs from a topical application, it usually progresses rapidly to respiratory and cardiovascular collapse, and thus therapy must be instituted with more haste to avoid deaths. Fatal systemic toxic reactions from topically administered anesthetic drugs are, in effect, usually not due to well informed use of the drug but to misuse owing to less than complete understanding of absorption. Emphasis is placed on the causes, prophylaxis and treatment of severe systemic toxic reactions which follow the topical application of local anesthetic drugs. If systemic toxic reactions resulting from a safe dose of a local anesthetic agent are correctly treated, there will usually follow an uneventful recovery rather than a catastrophe. PMID:13343009

  12. [Facial locoregional anesthetics: principles and precautions].

    Science.gov (United States)

    Lefort, H; Lacroix, G; Cordier, A; Bey, E; Duhamel, P

    2009-12-01

    Facial locoregional anesthetics (ALR) with nervous blocks are simple and reliable to perform, need little technical resources with a very low iatrogenic risk. These blocks allow anesthesia without deforming wound banks using the same materials as usual local anesthetic procedures. Three principal nervous blocks, in a straight line along the vertical pupil axis, allow managing - even extensive - facial wounds. Few side effects may occur which can be easily prevented. It is a good alternative to local anesthetic for the treatment of extensive and deep areas which is performed with a lower number of injections and a high rate of success. These techniques are easy to learn and practise. These anesthetic techniques allow a nice treatment of different kinds of facial wounds from simple suture to flaps.

  13. Local anesthetics: dentistry's most important drugs.

    Science.gov (United States)

    Malamed, S F

    1994-12-01

    One hundred and fifty years ago, Horace Wells opened the door to local anesthetics. Since then, many advances have been made in pain control. The development of dentistry's most important drugs is highlighted here.

  14. Anesthetizing animals: Similar to humans yet, peculiar?

    OpenAIRE

    Madhuri S Kurdi; Ramaswamy, Ashwini H

    2015-01-01

    From time immemorial, animals have served as models for humans. Like humans, animals too have to undergo several types of elective and emergency surgeries. Several anesthetic techniques and drugs used in humans are also used in animals. However, unlike humans, the animal kingdom includes a wide variety of species, breeds, and sizes. Different species have variable pharmacological responses, anatomy, temperament, behavior, and lifestyles. The anesthetic techniques and drugs have to suit differ...

  15. [Evoked potentials and inhalation anesthetics].

    Science.gov (United States)

    Thiel, A; Russ, W; Hempelmann, G

    1988-01-01

    Intraoperative monitoring of evoked potentials can be affected by various factors including volatile anaesthetics. These effects have to be considered in order to give correct interpretations of the obtained data. Visual evoked potentials (VEP) and auditory evoked potentials (AEP) will show strong alterations under general anaesthesia whereas brainstem auditory evoked potentials (BAEP) are slightly affected. The effects of nitrous oxide, halothane, enflurane, and isoflurane on somatosensory evoked potentials (SEP) after median nerve stimulation were studied in 35 healthy adult patients. pCO2 and tympanic membrane temperature were held constant. Simultaneous cervical and cortical SEP recording was performed using surface electrodes. After induction of anaesthesia SEP were recorded during normoventilation with 100% oxygen and after inhalation of 66.6% nitrous oxide. 10 patients received halothane at inspired concentrations of 0.5, 1.0, 1.5, and 2.0%. After nitrous oxide had been replaced by oxygen, halothane was reduced in steps of 0.5%. SEP were recorded at the end of each period (15 min). Equipotent doses of enflurane or isoflurane were administered to 15 and 10 patients, respectively. Nitrous oxide depressed early cortical SEP amplitude. Halothane, enflurane, and isoflurane caused dose dependent increases of latencies. Reduction of amplitude was most pronounced with isoflurane. Using high doses of enflurane in oxygen cortical SEP showed unusual high amplitudes associated with marked increases of latencies. Even under high concentrations of volatile anaesthetics cervical SEP were minimally affected. The effects of anaesthetic gases have to be considered when SEP are recorded intraoperatively.

  16. A high-throughput approach for identification of novel general anesthetics.

    Science.gov (United States)

    Lea, Wendy A; Xi, Jin; Jadhav, Ajit; Lu, Louis; Austin, Christopher P; Simeonov, Anton; Eckenhoff, Roderic G

    2009-09-24

    Anesthetic development has been a largely empirical process. Recently, we described a GABAergic mimetic model system for anesthetic binding, based on apoferritin and an environment-sensitive fluorescent probe. Here, a competition assay based on 1-aminoanthracene and apoferritin has been taken to a high throughput screening level, and validated using the LOPAC(1280) library of drug-like compounds. A raw hit rate of approximately 15% was reduced through the use of computational filters to yield an overall hit rate of approximately 1%. These hits were validated using isothermal titration calorimetry. The success of this initial screen and computational triage provides feasibility to undergo a large scale campaign to discover novel general anesthetics.

  17. A high-throughput approach for identification of novel general anesthetics.

    Directory of Open Access Journals (Sweden)

    Wendy A Lea

    Full Text Available Anesthetic development has been a largely empirical process. Recently, we described a GABAergic mimetic model system for anesthetic binding, based on apoferritin and an environment-sensitive fluorescent probe. Here, a competition assay based on 1-aminoanthracene and apoferritin has been taken to a high throughput screening level, and validated using the LOPAC(1280 library of drug-like compounds. A raw hit rate of approximately 15% was reduced through the use of computational filters to yield an overall hit rate of approximately 1%. These hits were validated using isothermal titration calorimetry. The success of this initial screen and computational triage provides feasibility to undergo a large scale campaign to discover novel general anesthetics.

  18. Articaine - the best choice of local anesthetic in contemporary dentistry.

    Science.gov (United States)

    Nizharadze, N; Mamaladze, M; Chipashvili, N; Vadachkoria, D

    2011-01-01

    Local anesthesia forms the foundation of pain control techniques in clinical dentistry. Within the rich local anesthetic drugs available in dentistry for the prevention and management of pain 4% articaine solutions achieve highest level of anesthetic potency and lowest systemic toxicity in all clinical situations, prior to its superlative physicochemical characteristics and the pharmacological profile. These are - low lipid solubility, high plasma protein binding rate, fast metabolization, fast elimination half time; low blood level. Articaine inactivates in both ways: in the liver and the blood serum. It has good spreading through tissues. Thus, articaine seems to be the local anesthetic of first choice in tissues with suppurative inflammation, for adults, children (over 4), elderly, pregnant women, breastfeeding women, patients suffering from hepatic disorders and renal function impairment. In Articaine solutions (1: 200,000) epinephrine is in low concentration, thus in patients at high risk adverse responses are maximally decreased. In these patients articaine should be used with careful consideration of risk/benefit ratio. Articaine solutions must not be used in persons who are allergic or hypersensitive to sulphite, due to content of Sodium metabisulfite as vasoconstrictor's antioxidant in it. Incidence of serious adverse effects related to dental anesthesia with articaine is very low. Toxic reactions are usually due to an inadvertent intravascular injection or use of excessive dose. To avoid overdoses maximum recommendation dose (MRD) must not be exceeded and aspiration test always performed prior all LA injections. In these article we introduce new graphs providing a quick and effect way to determine maximum LA dose. If the overdose reactions develop, adherence to the basic step of emergency management with end to a successful outcome in virtually all cases.

  19. [Anesthetic management of a pediatric patient with non-Fukuyama type congenital muscular dystrophy].

    Science.gov (United States)

    O'Higashi, T; Kato, S; Shirakami, G; Hirota, K; Suzuki, S; Sasai, S

    1997-01-01

    Non-Fukuyama type congenital muscular dystrophy (n-FCMD), a subtype of progressive muscular dystrophy (PMD), is a very rare autosomal recessive disorder. N-FCMD is characterized by severe and progressive motor weakness and atrophies of proximal muscles during the infant period. A 9-year-old boy with n-FCMD underwent elective surgery for muscle release around the hip joints bilaterally. As many perioperative complications related with volatile anesthetics and muscle relaxants had been reported in the anesthetic management of PMD, these drugs were thought to be contraindicated in patients with n-FCMD. Because n-FCMD seemed to have very similar pathogenesis with PMD, caudal epidural block was chosen, supplemented with the administration of diazepam, pentazocine and nitrous oxide. The operation and anesthesia were conducted uneventfully. No complications occurred postoperatively.

  20. Pricing Volatility Referenced Assets

    Directory of Open Access Journals (Sweden)

    Alan De Genaro Dario

    2006-12-01

    Full Text Available Volatility swaps are contingent claims on future realized volatility. Variance swaps are similar instruments on future realized variance, the square of future realized volatility. Unlike a plain vanilla option, whose volatility exposure is contaminated by its asset price dependence, volatility and variance swaps provide a pure exposure to volatility alone. This article discusses the risk-neutral valuation of volatility and variance swaps based on the framework outlined in the Heston (1993 stochastic volatility model. Additionally, the Heston (1993 model is calibrated for foreign currency options traded at BMF and its parameters are used to price swaps on volatility and variance of the BRL / USD exchange rate.

  1. Knowledge about local anesthetics in odontology students.

    Science.gov (United States)

    Guzmán Alvarez, Rodrigo; Campos Sepúlveda, Alfonso Efraín; Martínez González, Adrian Alejandro

    2009-01-01

    The purpose of the study was to identify the level of knowledge of local anesthetics frequently used in the surgical clinic by third and fourth year dental students in daily practice. The importance of pharmacology in dental practice in underscored by potential drug toxicity. The study was performed with 244 third and fourth grade career dental students (CDS). Eleven items regarding the knowledge over local anesthetics at the clinic; i.e., the appropriate doses, possible toxic effects and side effects were examined. The reference questionnaire which is in a validation process, is a way to evaluate student knowledge about most drugs used in odontology practice such as: NSAIDs, antibiotics and local anesthetics. The results were found to be unsatisfactory with a high percentage of students failing (less than six of eleven items correct). We conclude that determination of practice knowledge is an essential step in informing the institution about cognitive deficiencies identified in order to plan learning solutions.

  2. The sodium channel as a target for local anesthetic drugs

    Directory of Open Access Journals (Sweden)

    Harry A Fozzard

    2011-11-01

    Full Text Available Na channels are the source of excitatory currents for the nervous system and muscle. They are the target for a class of drugs called local anesthetics (LA, which have been used for local and regional anesthesia and for excitatory dysfunction problems such as epilepsy and cardiac arrhythmia. LA drugs are prototypes for new analgesic drugs. The LA drug binding site has been localized to the inner pore of the channel, where drugs interact mainly with a phenylalanine in domain IV S6. Drug affinity is both voltage- and use-dependent. Voltage-dependency is the result of changes in the conformation of the inner pore during channel activation and opening, allowing high energy interaction of drugs with the phenylalanine. LA drugs also reduce the gating current of Na channels, which represents the movement of charged residues in the voltage sensors. Specifically, drug binding to phenylalanine locks the domain III S4 in its outward (activated position, and slows recovery of the domain IV S4. Although strongly affecting gating, LA drugs almost certainly also block by steric occlusion of the pore. Molecular definition of the binding and blocking interactions may help in new drug development.

  3. Participation of the GABAergic system in the anesthetic effect of Lippia alba (Mill.) N.E. Brown essential oil

    Energy Technology Data Exchange (ETDEWEB)

    Heldwein, C.G.; Silva, L.L. [Departamento de Farmácia Industrial, Universidade Federal de Santa Maria, Santa Maria, RS (Brazil); Reckziegel, P. [Departamento de Fisiologia e Farmacologia, Universidade Federal de Santa Maria, Santa Maria, RS (Brazil); Barros, F.M.C. [Departamento de Farmácia Industrial, Universidade Federal de Santa Maria, Santa Maria, RS (Brazil); Bürger, M.E.; Baldisserotto, B. [Departamento de Fisiologia e Farmacologia, Universidade Federal de Santa Maria, Santa Maria, RS (Brazil); Mallmann, C.A. [Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, Santa Maria, RS (Brazil); Schmidt, D.; Caron, B.O. [Departamento de Ciências Agronômicas e Ambientais, Universidade Federal de Santa Maria, Campus de Frederico Westphalen, Frederico Westphalen, RS (Brazil); Heinzmann, B.M. [Departamento de Farmácia Industrial, Universidade Federal de Santa Maria, Santa Maria, RS (Brazil)

    2012-04-05

    The objective of this study was to identify the possible involvement of the GABAergic system in the anesthetic effect of Lippia alba essential oil (EO). We propose a new animal model using silver catfish (Rhamdia quelen) exposed to an anesthetic bath to study the mechanism of action of EO. To observe the induction and potentiation of the anesthetic effect of EO, juvenile silver catfish (9.30 ± 1.85 g; 10.15 ± 0.95 cm; N = 6) were exposed to various concentrations of L. alba EO in the presence or absence of diazepam [an agonist of high-affinity binding sites for benzodiazepinic (BDZ) sites coupled to the GABA{sub A} receptor complex]. In another experiment, fish (N = 6) were initially anesthetized with the EO and then transferred to an anesthetic-free aquarium containing flumazenil (a selective antagonist of binding sites for BDZ coupled to the GABA{sub A} receptor complex) or water to assess recovery time from the anesthesia. In this case, flumazenil was used to observe the involvement of the GABA-BDZ receptor in the EO mechanism of action. The results showed that diazepam potentiates the anesthetic effect of EO at all concentrations tested. Fish exposed to diazepam and EO showed faster recovery from anesthesia when flumazenil was added to the recovery bath (12.0 ± 0.3 and 7.2 ± 0.7, respectively) than those exposed to water (9.2 ± 0.2 and 3.5 ± 0.3, respectively). In conclusion, the results demonstrated the involvement of the GABAergic system in the anesthetic effect of L. alba EO on silver catfish.

  4. Participation of the GABAergic system in the anesthetic effect of Lippia alba (Mill. N.E. Brown essential oil

    Directory of Open Access Journals (Sweden)

    C.G. Heldwein

    2012-05-01

    Full Text Available The objective of this study was to identify the possible involvement of the GABAergic system in the anesthetic effect of Lippia alba essential oil (EO. We propose a new animal model using silver catfish (Rhamdia quelen exposed to an anesthetic bath to study the mechanism of action of EO. To observe the induction and potentiation of the anesthetic effect of EO, juvenile silver catfish (9.30 ± 1.85 g; 10.15 ± 0.95 cm; N = 6 were exposed to various concentrations of L. alba EO in the presence or absence of diazepam [an agonist of high-affinity binding sites for benzodiazepinic (BDZ sites coupled to the GABA A receptor complex]. In another experiment, fish (N = 6 were initially anesthetized with the EO and then transferred to an anesthetic-free aquarium containing flumazenil (a selective antagonist of binding sites for BDZ coupled to the GABA A receptor complex or water to assess recovery time from the anesthesia. In this case, flumazenil was used to observe the involvement of the GABA-BDZ receptor in the EO mechanism of action. The results showed that diazepam potentiates the anesthetic effect of EO at all concentrations tested. Fish exposed to diazepam and EO showed faster recovery from anesthesia when flumazenil was added to the recovery bath (12.0 ± 0.3 and 7.2 ± 0.7, respectively than those exposed to water (9.2 ± 0.2 and 3.5 ± 0.3, respectively. In conclusion, the results demonstrated the involvement of the GABAergic system in the anesthetic effect of L. alba EO on silver catfish.

  5. Participation of the GABAergic system in the anesthetic effect of Lippia alba (Mill.) N.E. Brown essential oil.

    Science.gov (United States)

    Heldwein, C G; Silva, L L; Reckziegel, P; Barros, F M C; Bürger, M E; Baldisserotto, B; Mallmann, C A; Schmidt, D; Caron, B O; Heinzmann, B M

    2012-05-01

    The objective of this study was to identify the possible involvement of the GABAergic system in the anesthetic effect of Lippia alba essential oil (EO). We propose a new animal model using silver catfish (Rhamdia quelen) exposed to an anesthetic bath to study the mechanism of action of EO. To observe the induction and potentiation of the anesthetic effect of EO, juvenile silver catfish (9.30 ± 1.85 g; 10.15 ± 0.95 cm; N = 6) were exposed to various concentrations of L. alba EO in the presence or absence of diazepam [an agonist of high-affinity binding sites for benzodiazepinic (BDZ) sites coupled to the GABA A receptor complex]. In another experiment, fish (N = 6) were initially anesthetized with the EO and then transferred to an anesthetic-free aquarium containing flumazenil (a selective antagonist of binding sites for BDZ coupled to the GABA A receptor complex) or water to assess recovery time from the anesthesia. In this case, flumazenil was used to observe the involvement of the GABA-BDZ receptor in the EO mechanism of action. The results showed that diazepam potentiates the anesthetic effect of EO at all concentrations tested. Fish exposed to diazepam and EO showed faster recovery from anesthesia when flumazenil was added to the recovery bath (12.0 ± 0.3 and 7.2 ± 0.7, respectively) than those exposed to water (9.2 ± 0.2 and 3.5 ± 0.3, respectively). In conclusion, the results demonstrated the involvement of the GABAergic system in the anesthetic effect of L. alba EO on silver catfish.

  6. Antimicrobial effects of liquid anesthetic isoflurane on Candida albicans

    Science.gov (United States)

    Barodka, Viachaslau M; Acheampong, Edward; Powell, Garry; Lobach, Ludmila; Logan, David A; Parveen, Zahida; Armstead, Valerie; Mukhtar, Muhammad

    2006-01-01

    Candida albicans is a dimorphic fungus that can grow in yeast morphology or hyphal form depending on the surrounding environment. This ubiquitous fungus is present in skin and mucus membranes as a potential pathogen that under opportunistic conditions causes a series of systemic and superficial infections known as candidiasis, moniliasis or simply candidiasis. There has been a steady increase in the prevalence of candidiasis that is expressed in more virulent forms of infection. Although candidiasis is commonly manifested as mucocutaneous disease, life-threatening systemic invasion by this fungus can occur in every part of the body. The severity of candidal infections is associated with its morphological shift such that the hyphal morphology of the fungus is most invasive. Of importance, aberrant multiplication of Candida yeast is also associated with the pathogenesis of certain mucosal diseases. In this study, we assessed the anti-candidal activity of the volatile anesthetic isoflurane in liquid form in comparison with the anti-fungal agent amphotericin B in an in vitro culture system. Exposure of C. albicans to isoflurane (0.3% volume/volume and above) inhibited multiplication of yeast as well as formation of hyphae. These data suggest development of potential topical application of isoflurane for controlling a series of cutaneous and genital infections associated with this fungus. Elucidiation of the mechanism by which isoflurane effects fungal growth could offer therapeutic potential for certain systemic fungal infections. PMID:17094810

  7. Antimicrobial effects of liquid anesthetic isoflurane on Candida albicans

    Directory of Open Access Journals (Sweden)

    Armstead Valerie

    2006-11-01

    Full Text Available Abstract Candida albicans is a dimorphic fungus that can grow in yeast morphology or hyphal form depending on the surrounding environment. This ubiquitous fungus is present in skin and mucus membranes as a potential pathogen that under opportunistic conditions causes a series of systemic and superficial infections known as candidiasis, moniliasis or simply candidiasis. There has been a steady increase in the prevalence of candidiasis that is expressed in more virulent forms of infection. Although candidiasis is commonly manifested as mucocutaneous disease, life-threatening systemic invasion by this fungus can occur in every part of the body. The severity of candidal infections is associated with its morphological shift such that the hyphal morphology of the fungus is most invasive. Of importance, aberrant multiplication of Candida yeast is also associated with the pathogenesis of certain mucosal diseases. In this study, we assessed the anti-candidal activity of the volatile anesthetic isoflurane in liquid form in comparison with the anti-fungal agent amphotericin B in an in vitro culture system. Exposure of C. albicans to isoflurane (0.3% volume/volume and above inhibited multiplication of yeast as well as formation of hyphae. These data suggest development of potential topical application of isoflurane for controlling a series of cutaneous and genital infections associated with this fungus. Elucidiation of the mechanism by which isoflurane effects fungal growth could offer therapeutic potential for certain systemic fungal infections.

  8. Allyl m-Trifluoromethyldiazirine Mephobarbital: An Unusually Potent Enantioselective and Photoreactive Barbiturate General Anesthetic

    Energy Technology Data Exchange (ETDEWEB)

    Savechenkov, Pavel Y.; Zhang, Xi; Chiara, David C.; Stewart, Deirdre S.; Ge, Rile; Zhou, Xiaojuan; Raines, Douglas E.; Cohen, Jonathan B.; Forman, Stuart A.; Miller, Keith W.; Bruzik, Karol S. (Harvard-Med); (Mass. Gen. Hosp.); (UIC)

    2012-12-10

    We synthesized 5-allyl-1-methyl-5-(m-trifluoromethyl-diazirynylphenyl)barbituric acid (14), a trifluoromethyldiazirine-containing derivative of general anesthetic mephobarbital, separated the racemic mixture into enantiomers by chiral chromatography, and determined the configuration of the (+)-enantiomer as S by X-ray crystallography. Additionally, we obtained the {sup 3}H-labeled ligand with high specific radioactivity. R-(-)-14 is an order of magnitude more potent than the most potent clinically used barbiturate, thiopental, and its general anesthetic EC{sub 50} approaches those for propofol and etomidate, whereas S-(+)-14 is 10-fold less potent. Furthermore, at concentrations close to its anesthetic potency, R-(-)-14 both potentiated GABA-induced currents and increased the affinity for the agonist muscimol in human {alpha}1{beta}2/3{gamma}2L GABA{sub A} receptors. Finally, R-(-)-14 was found to be an exceptionally efficient photolabeling reagent, incorporating into both {alpha}1 and {beta}3 subunits of human {alpha}1{beta}3 GABAA receptors. These results indicate R-(-)-14 is a functional general anesthetic that is well-suited for identifying barbiturate binding sites on Cys-loop receptors.

  9. Ketamine-Based Anesthetic Protocols and Evoked Potential Monitoring: A Risk/Benefit Overview

    Science.gov (United States)

    Stoicea, Nicoleta; Versteeg, Gregory; Florescu, Diana; Joseph, Nicholas; Fiorda-Diaz, Juan; Navarrete, Víctor; Bergese, Sergio D.

    2016-01-01

    Since its discovery, ketamine, a non-competitive N-methyl D-aspartate (NMDA) receptor antagonist related to phencyclidine, has been linked to multiple adverse reactions sometimes described as “out of body” and “near death experiences,” including emergence phenomena, delusions, hallucinations, delirium, and confusion. Due to these effects, ketamine has been withdrawn from mainstream anesthetic use in adult patients. Evoked potentials (EPs) are utilized to monitor neural pathways during surgery, detect intraoperative stress or damage, detect and define the level of neural lesions, and define abnormalities. Unfortunately, many of the volatile anesthetics commonly used during spinal and neurologic procedures suppress EP amplitude and monitoring. Ketamine has been found in several preclinical and clinical studies to actually increase EP amplitude and thus has been used as an analgesic adjunct in procedures where EP monitoring is critical. Once the gap in our knowledge of ketamine's risks has been sufficiently addressed in animal models, informed clinical trials should be conducted in order to properly incorporate ketamine-based anesthetic regimens during EP-monitored neurosurgeries. PMID:26909017

  10. Hypoxic pulmonary vasoconstriction: physiology and anesthetic implications.

    Science.gov (United States)

    Lumb, Andrew B; Slinger, Peter

    2015-04-01

    Hypoxic pulmonary vasoconstriction (HPV) represents a fundamental difference between the pulmonary and systemic circulations. HPV is active in utero, reducing pulmonary blood flow, and in adults helps to match regional ventilation and perfusion although it has little effect in healthy lungs. Many factors affect HPV including pH or PCO2, cardiac output, and several drugs, including antihypertensives. In patients with lung pathology and any patient having one-lung ventilation, HPV contributes to maintaining oxygenation, so anesthesiologists should be aware of the effects of anesthesia on this protective reflex. Intravenous anesthetic drugs have little effect on HPV, but it is attenuated by inhaled anesthetics, although less so with newer agents. The reflex is biphasic, and once the second phase becomes active after about an hour of hypoxia, this pulmonary vasoconstriction takes hours to reverse when normoxia returns. This has significant clinical implications for repeated periods of one-lung ventilation.

  11. Opioid induced hyperalgesia in anesthetic settings.

    Science.gov (United States)

    Lee, Hyeon Jeong; Yeomans, David C

    2014-11-01

    Pain is difficult to investigate and difficult to treat, in part, because of problems in quantification and assessment. The use of opioids, combined with classic anesthetics to maintain hemodynamic stability by controlling responses to intraoperative painful events has gained significant popularity in the anesthetic field. However, several side effects profiles concerning perioperative use of opioid have been published. Over the past two decades, many concerns have arisen with respect to opioid-induced hyperalgesia (OIH), which is the paradoxical effect wherein opioid usage may decrease pain thresholds and increase atypical pain unrelated to the original, preexisting pain. This brief review focuses on the evidence, mechanisms, and modulatory and pharmacologic management of OIH in order to elaborate on the clinical implication of OIH.

  12. Child with aplastic anemia: Anesthetic management

    OpenAIRE

    Manpreet Kaur; Babita Gupta; Aanchal Sharma; Sanjeev Sharma

    2012-01-01

    Aplastic anemia is a rare heterogeneous disorder of hematopoietic stem cells causing pancytopenia and marrow hypoplasia with the depletion of all types of blood cells. This results in anemia, neutropenia and thrombocytopenia, which pose a challenge to both surgical and anesthetic management of such cases. We report a child with aplastic anemia who sustained traumatic ulcer on the arm and underwent split-thickness skin grafting under general anesthesia. There are only two case reports on anest...

  13. From micro- to nanostructured implantable device for local anesthetic delivery.

    Science.gov (United States)

    Zorzetto, Laura; Brambilla, Paola; Marcello, Elena; Bloise, Nora; De Gregori, Manuela; Cobianchi, Lorenzo; Peloso, Andrea; Allegri, Massimo; Visai, Livia; Petrini, Paola

    2016-01-01

    Local anesthetics block the transmission of painful stimuli to the brain by acting on ion channels of nociceptor fibers, and find application in the management of acute and chronic pain. Despite the key role they play in modern medicine, their cardio and neurotoxicity (together with their short half-life) stress the need for developing implantable devices for tailored local drug release, with the aim of counterbalancing their side effects and prolonging their pharmacological activity. This review discusses the evolution of the physical forms of local anesthetic delivery systems during the past decades. Depending on the use of different biocompatible materials (degradable polyesters, thermosensitive hydrogels, and liposomes and hydrogels from natural polymers) and manufacturing processes, these systems can be classified as films or micro- or nanostructured devices. We analyze and summarize the production techniques according to this classification, focusing on their relative advantages and disadvantages. The most relevant trend reported in this work highlights the effort of moving from microstructured to nanostructured systems, with the aim of reaching a scale comparable to the biological environment. Improved intracellular penetration compared to microstructured systems, indeed, provides specific drug absorption into the targeted tissue and can lead to an enhancement of its bioavailability and retention time. Nanostructured systems are realized by the modification of existing manufacturing processes (interfacial deposition and nanoprecipitation for degradable polyester particles and high- or low-temperature homogenization for liposomes) or development of novel strategies (electrospun matrices and nanogels). The high surface-to-volume ratio that characterizes nanostructured devices often leads to a burst drug release. This drawback needs to be addressed to fully exploit the advantage of the interaction between the target tissues and the drug: possible strategies

  14. A cyclodextrin formulation to improve use of the anesthetic tribromoethanol (Avertin ®

    Directory of Open Access Journals (Sweden)

    Arlene McDowell

    2014-01-01

    Full Text Available Objective: Efficacy and safety concerns have been raised in the literature with the use of tribromoethanol (TBE (Avertin ® for anesthesia in rats and mice when administered by intraperitoneal (IP injection. Despite the controversy, it remains in common usage as an anesthetic agent in laboratory rodents for short-term surgical procedures. Cyclodextrins have been shown to improve drug solubility and were investigated here as an improved anesthetic formulation for mice. Materials and Methods: The phase solubility of TBE with hydroxypropyl-β-cyclodextrin (HP-β-CD was estimated. The efficacy of two anesthetic regimens was compared in this study; the conventional TBE formulation solubilized in tert-amyl alcohol and a HP-β-CD formulation containing TBE. Mice (n = 6 were administered the formulations by IP injection and the pharmacodynamic parameters of time to induction of anesthesia, duration of anesthesia and recovery time were measured using a combined reflex score (CRS. Results and Discussion: Phase solubility studies showed a linear increase in the solubility of TBE with increasing HP-β-CD concentration and suggested >1:1 binding of the drug in the cyclodextrin complex. At a dose of 260 mg/kg the standard TBE formulation appeared to produce deeper anesthesia than the cyclodextrin formulation, with a minimum average CRS of 1.8 compared with 5.2. No post-mortem pathology was observed in mice that received either the conventional or cyclodextrin formulation. Conclusion: The cyclodextrin TBE formulation did not conclusively provide an improved anesthetic response at a dose of 260 mg/kg compared with the conventional formulation. The improved solubility of TBE with HP-β-CD and the reduced variability in anesthetic response warrants the further investigation of this formulation. This study has also identified the value of using the anticholinergic atropine in association with TBE for anesthesia.

  15. Volatile Organic Compounds (VOCs)

    Science.gov (United States)

    ... Share Facebook Twitter Google+ Pinterest Contact Us Volatile Organic Compounds' Impact on Indoor Air Quality On this ... Exposure Standards or Guidelines Additional Resources Introduction Volatile organic compounds (VOCs) are emitted as gases from certain ...

  16. Upper airway collapsibility in anesthetized children.

    Science.gov (United States)

    Litman, Ronald S; McDonough, Joseph M; Marcus, Carole L; Schwartz, Alan R; Ward, Denham S

    2006-03-01

    We sought to establish the feasibility of measuring upper airway narrowing in spontaneously breathing, anesthetized children using dynamic application of negative airway pressure. A secondary aim was to compare differences in upper airway collapsibility after the administration of sevoflurane or halothane. Subjects were randomized to either drug for inhaled anesthetic induction. Each was adjusted to their 1 MAC value (0.9% for halothane and 2.5% for sevoflurane) and a blinded anesthesia provider held the facemask without performing manual airway opening maneuvers but with inclusion of an oral airway device. Inspiratory flows were measured during partial upper airway obstruction created by an adjustable negative pressure-generating vacuum motor inserted into the anesthesia circuit. Critical closing pressure of the pharynx (Pcrit) was obtained by plotting the peak inspiratory flow of the obstructed breaths against the corresponding negative pressure in the facemask and extrapolating to zero airflow using linear correlation. Fourteen children were enrolled, seven in each anesthetic group. Two children in the halothane group did not develop flow-limited airway obstruction despite negative pressures as low as -9 cm H2O. Pcrit for sevoflurane ranged from -6.7 to -11.6 (mean +/- sd, -9.8 +/- 1.9) cm H2O. Pcrit for halothane ranged from -8.1 to -33 (mean +/- sd, -19.4 +/- 9.3) cm H2O (sevoflurane versus halothane, P = 0.048). We conclude that when using dynamic application of negative airway pressure, halothane appears to cause less upper airway obstruction than sevoflurane at equipotent concentrations.

  17. Interaction of anesthetics with neurotransmitter release machinery proteins.

    Science.gov (United States)

    Xie, Zheng; McMillan, Kyle; Pike, Carolyn M; Cahill, Anne L; Herring, Bruce E; Wang, Qiang; Fox, Aaron P

    2013-02-01

    General anesthetics produce anesthesia by depressing central nervous system activity. Activation of inhibitory GABA(A) receptors plays a central role in the action of many clinically relevant general anesthetics. Even so, there is growing evidence that anesthetics can act at a presynaptic locus to inhibit neurotransmitter release. Our own data identified the neurotransmitter release machinery as a target for anesthetic action. In the present study, we sought to examine the site of anesthetic action more closely. Exocytosis was stimulated by directly elevating the intracellular Ca(2+) concentration at neurotransmitter release sites, thereby bypassing anesthetic effects on channels and receptors, allowing anesthetic effects on the neurotransmitter release machinery to be examined in isolation. Three different PC12 cell lines, which had the expression of different release machinery proteins stably suppressed by RNA interference, were used in these studies. Interestingly, there was still significant neurotransmitter release when these knockdown PC12 cells were stimulated. We have previously shown that etomidate, isoflurane, and propofol all inhibited the neurotransmitter release machinery in wild-type PC12 cells. In the present study, we show that knocking down synaptotagmin I completely prevented etomidate from inhibiting neurotransmitter release. Synaptotagmin I knockdown also diminished the inhibition produced by propofol and isoflurane, but the magnitude of the effect was not as large. Knockdown of SNAP-25 and SNAP-23 expression also changed the ability of these three anesthetics to inhibit neurotransmitter release. Our results suggest that general anesthetics inhibit the neurotransmitter release machinery by interacting with multiple SNARE and SNARE-associated proteins.

  18. Anesthetic considerations in Sheldon-Hall syndrome.

    Science.gov (United States)

    Anderson, Thomas Anthony; Kasser, James R; Holzman, Robert S

    2014-05-01

    Arthrogryposis is characterized by multiple, nonprogressive joint contractures which may be caused by maternal disorders such as oligohydramnios as well as fetal akinesia resulting from primary disorders of muscle, connective tissue, or neurologic tissue. Its prevalence is about 1 : 3000. Distal arthrogryposis (DA) is a heterogenous group of genetic disorders with a characteristic flexion of the joints of the hands and feet divided into different types with additional features. Sheldon-Hall Syndrome (SHS), also known as distal arthrogryposis type 2A (DA2A), has some nonorthopedic features of specific importance to anesthetic care.

  19. Local anesthetics as pain therapy in horses.

    Science.gov (United States)

    Doherty, Thomas J; Seddighi, M Reza

    2010-12-01

    This article describes the rationale behind the use of systemically administered lidocaine as an analgesic. The analgesic efficacy of intravenously administered lidocaine is well documented by studies in human patients and laboratory animals. The mechanism by which systemically administered lidocaine produces analgesia is uncertain but is thought to include action at sodium, calcium, and potassium channels and the N-methyl-D-aspartate acid receptor. In addition, the anti-inflammatory actions of lidocaine are important in producing analgesia because inflammatory mediators augment neuronal excitability. The available studies of systemically administered lidocaine in horses provide evidence for the analgesic and anesthetic effects of intravenous lidocaine in this species.

  20. Gestational trophoblastic disease with hyperthyroidism: Anesthetic management

    Directory of Open Access Journals (Sweden)

    Puneet Khanna

    2012-01-01

    Full Text Available The coexistence of hyperthyroidism with gestational trophoblastic disease is a known albeit rare clinical condition. We herein report the successful anesthetic management of such a case in our institute. There are only few case reports in literature of this association. Often, the diagnosis of hyperthyroid state is retrospective one, as it can be missed in the emergency scenario of patient requiring molar evacuation. This case report highlights the perioperative management and optimization of hyperthyroid state prior to surgical evacuation of the invasive hydatidiform mole.

  1. Relationship between pre-anesthetic and intra-anesthetic airway resistance in patients undergoing general anesthesia: A prospective observational study

    Science.gov (United States)

    Ikeda, Takamitsu; Uchida, Kanji; Yamauchi, Yasuhiro; Nagase, Takahide; Oba, Koji; Yamada, Yoshitsugu

    2017-01-01

    Surgery patients in Japan undergo routine spirometry testing prior to general anesthesia. The use of a flow sensor during general anesthesia has recently become common. However, it is not certain whether the information derived from flow-volume curves is being adequately used for mechanical ventilation management during general anesthesia. So far, there have been no attempts to calculate airway resistance using flow-volume curves. Therefore, we performed a prospective, observational study to investigate the relationship between pre-anesthetic and intra-anesthetic airway resistance in patients scheduled for surgery under general anesthesia. We calculated pre-anesthetic and intra-anesthetic airway resistance in each patient, based on the slopes of flow-volume curves obtained prior to and during general anesthesia. We also calculated endotracheal tube resistance to correct the intra-anesthetic airway resistance values calculated. A total of 526 patients were included in the study, and 98 patients had a forced expiratory volume in the first second/forced vital capacity ratio of mechanical ventilation (p = 0.48). Pre-anesthetic and intra-anesthetic airway resistance values were closer to each other in patients without airflow obstruction, with a mean difference < 1.0 cmH2O L-1s-1, than in those with airflow obstruction, although these respiratory parameters were significantly different (p < 0.001). Intra-anesthetic airway resistance was not related to the FEV1/FVC ratio, regardless of the degree to which the FEV1/FVC ratio reflected pre-anesthetic airway resistance. As compared with patients with airflow obstruction, the mean difference between pre-anesthetic and intra-anesthetic airway resistance was small in patients without airflow obstruction. PMID:28212451

  2. Huntington's disease: review and anesthetic case management.

    Science.gov (United States)

    Cangemi, C F; Miller, R J

    1998-01-01

    Huntington's disease is a dominantly inherited progressive autosomal disease that affects the basal ganglia. Symptoms appear later in life and manifest as progressive mental deterioration and involuntary choreiform movements. Patients with Huntington's disease develop a progressive but variable dementia. Dysphagia, the most significant related motor symptom, hinders nutrition intake and places the patient at risk for aspiration. The combination of involuntary choreoathetoid movements, depression, and apathy leads to cachexia. Factors of considerable concern to the anesthesiologist who treats patients with Huntington's disease may include how to treat frail elderly people incapable of cooperation, how to treat patients suffering from malnourishment, and how to treat patients with an increased risk for aspiration or exaggerated responses to sodium thiopental and succinylcholine. The successful anesthetic management of a 65-yr-old woman with Huntington's disease who presented for full-mouth extractions is described.

  3. Renal effects of methoxyverapamil in anesthetized rats.

    Science.gov (United States)

    Brown, B; Churchill, P

    1983-05-01

    The purpose of these experiments was to determine the renal effects of methoxyverapamil (D-600). Three groups of rats were anesthetized with sodium pentobarbital and given 0, 0.85 or 1.69 nmol/min of methoxyverapamil i.v. Increases in urine flow and Na, K and Ca excretory rates occurred, in an apparently dose-dependent manner. Plasma Na and arterial renin concentration decreased at both doses and, at the higher dose, mean arterial blood pressure and effective renal plasma flow decreased while plasma K increased. Plasma Ca, glomerular filtration rate, filtration fraction and total renal plasma flow were not affected. The findings that methoxyverapamil increased urine flow and electrolyte excretion without changing glomerular filtration rate are consistent with the hypothesis that methoxyverapamil acts directly on tubular reabsorptive mechanisms. These effects, and the effect on plasma renin concentration, could contribute to the beneficial effects of this and other Ca entry antagonists in the treatment of hypertension.

  4. Obstetric use of nitroglycerin: Anesthetic implications

    Science.gov (United States)

    Saroa, Richa; Sachan, Shikha; Palta, Sanjeev; Gombar, Satinder; Sahai, Nitika

    2013-01-01

    Nitroglycerin has been used in anesthetic practice for induced hypotension and managing perioperative hypertension and myocardial ischemia. Contrary to the continuous low dose infusions (5-20 mcg/min) used for the same, intravenous bolus dosages are sometimes administered at the behest of obstetricians for removal of retained placenta. Use of nitroglycerine in managing retained placenta is undertaken as a last resort when other measures fail to relax the uterine smooth muscles. Intravenous nitroglycerine relaxes smooth muscle cells by releasing nitric oxide thus causing prompt cervico-uterine relaxation. However, administration of nitroglycerine in this manner is not without risks which should be kept in mind while using it for obstetric purposes. We hereby report a case of 22-year-old female scheduled for manual removal of placenta where unpredictable and unexpected hypoxemia was observed following nitroglycerine administration. PMID:24015145

  5. Obstetric use of nitroglycerin: Anesthetic implications

    Directory of Open Access Journals (Sweden)

    Richa Saroa

    2013-01-01

    Full Text Available Nitroglycerin has been used in anesthetic practice for induced hypotension and managing perioperative hypertension and myocardial ischemia. Contrary to the continuous low dose infusions (5-20 mcg/min used for the same, intravenous bolus dosages are sometimes administered at the behest of obstetricians for removal of retained placenta. Use of nitroglycerine in managing retained placenta is undertaken as a last resort when other measures fail to relax the uterine smooth muscles. Intravenous nitroglycerine relaxes smooth muscle cells by releasing nitric oxide thus causing prompt cervico-uterine relaxation. However, administration of nitroglycerine in this manner is not without risks which should be kept in mind while using it for obstetric purposes. We hereby report a case of 22-year-old female scheduled for manual removal of placenta where unpredictable and unexpected hypoxemia was observed following nitroglycerine administration.

  6. Anesthetic management of transcatheter aortic valve implantation

    Directory of Open Access Journals (Sweden)

    Annalisa Franco

    2012-01-01

    Full Text Available Transcatheter aortic valve implantation (TAVI is an emergent technique for high-risk patients with aortic stenosis. TAVI poses significant challenges about its management because of the procedure itself and the population who undergo the implantation. Two devices are currently available and marketed in Europe and several other technologies are being developed. The retrograde transfemoral approach is the most popular procedure; nevertheless, it may not be feasible in patients with significant aortic or ileo-femoral arterial disease. Alternatives include a transaxillary approach, transapical approach, open surgical access to the retroperitoneal iliac artery and the ascending aorta. A complementary approach using both devices and alternative routes tailored to the anatomy and the comorbidities of the single patient is a main component for the successful implementation of a TAVI program. Anesthetic strategies vary in different centers. Local anesthesia or general anesthesia are both valid alternatives and can be applied according to the patient′s characteristics and procedural instances. General anesthesia offers many advantages, mainly regarding the possibility of an early diagnosis and treatment of possible complications through the use of transesophageal echocardiography. However, after the initial experiences, many groups began to employ, routinely, sedation plus local anesthesia for TAVI, and their procedural and periprocedural success demonstrates that it is feasible. TAVI is burdened with potential important complications: vascular injuries, arrhythmias, renal impairment, neurological complications, cardiac tamponade, prosthesis malpositioning and embolization and left main coronary artery occlusion. The aim of this work is to review the anesthetic management of TAVI based on the available literature.

  7. Effect of Lidocaine–Ketamine Infusions Combined with Morphine or Fentanyl in Sevoflurane-Anesthetized Pigs

    Science.gov (United States)

    Re, Michela; Canfrán, Susana; Largo, Carlota; de Segura, Ignacio A Gómez

    2016-01-01

    Providing lidocaine, ketamine, and an opioid greatly decreases the minimum alveolar concentration (MAC) of volatile anesthetics in dogs. However, the efficacy of this combination shows marked interspecies variation, and opioids are likely to be less effective in pigs than in other species. The aim of the study was to determine the effects of constant-rate infusion of lidocaine and ketamine combined with either morphine or fentanyl on the MAC of sevoflurane in pigs. In a prospective, randomized, crossover design, 8 healthy crossbred pigs were premedicated with ketamine and midazolam, and anesthesia was induced and maintained with sevoflurane. Pigs then received ketamine (0.6 mg/kg/h) and lidocaine (3 mg/kg/h) combined with either morphine (0.24 mg/kg/h; MLK) or fentanyl (0.0045 mg/kg/h; FLK) after a loading dose; the control group received Ringers lactate solution. The anesthetic-sparing action of the 2 infusion protocols was calculated according to the MAC, by using dewclaw clamping as the standard noxious stimulus. The sevoflurane MAC (mean ± 1 SD) was 2.0% ± 0.2%, 1.9% ± 0.4%, and 1.8% ± 0.2% in the control, MLK, and FLK groups, respectively. No differences among groups or treatments were found. In conclusion, the administration of MLK or FLK at the studied doses did not reduce the MAC of sevoflurane in pigs. PMID:27177566

  8. Effect of Lidocaine-Ketamine Infusions Combined with Morphine or Fentanyl in Sevoflurane-Anesthetized Pigs.

    Science.gov (United States)

    Re, Michela; Canfrán, Susana; Largo, Carlota; Gómez de Segura, Ignacioa A

    2016-01-01

    Providing lidocaine, ketamine, and an opioid greatly decreases the minimum alveolar concentration (MAC) of volatile anesthetics in dogs. However, the efficacy of this combination shows marked interspecies variation, and opioids are likely to be less effective in pigs than in other species. The aim of the study was to determine the effects of constant-rate infusion of lidocaine and ketamine combined with either morphine or fentanyl on the MAC of sevoflurane in pigs. In a prospective, randomized, crossover design, 8 healthy crossbred pigs were premedicated with ketamine and midazolam, and anesthesia was induced and maintained with sevoflurane. Pigs then received ketamine (0.6 mg/kg/h) and lidocaine (3 mg/kg/h) combined with either morphine (0.24 mg/kg/h; MLK) or fentanyl (0.0045 mg/kg/h; FLK) after a loading dose; the control group received Ringers lactate solution. The anesthetic-sparing action of the 2 infusion protocols was calculated according to the MAC, by using dewclaw clamping as the standard noxious stimulus. The sevoflurane MAC (mean ± 1 SD) was 2.0% ± 0.2%, 1.9% ± 0.4%, and 1.8% ± 0.2% in the control, MLK, and FLK groups, respectively. No differences among groups or treatments were found. In conclusion, the administration of MLK or FLK at the studied doses did not reduce the MAC of sevoflurane in pigs.

  9. The anesthetic effect of alcohols and alkanes in caenorhabditis elegans (C. E. )

    Energy Technology Data Exchange (ETDEWEB)

    Anton, A.H.; Berk, A.I.; Nicholls, C.H. (Case Western Reserve Univ., Cleveland, OH (United States))

    1991-03-11

    The authors colleagues reported that the non-parasitic roundworm, C.E., was reversibly immobilized by volatile anesthetics, whose potencies were directly related to their lipid solubilities as in other animals. In further studies on this phenomenon, they tested a homologous series of organic solvents, to determine whether they also had a reversible anesthetic effect in C.E. as in other animals. Synchronized 3-1/2 day-old cultures of about 100 worms each were exposed to increasing concentrations of the alcohols (C{sub 1} - C{sub 14}) and alkanes (C{sub 5} -C{sub 10}) in 15 ml sealed bottles in a volume of 0.5 ml. The dose that reversibly immobilized 50% of the worms was determined and a straight line was plotted against the octanol/water partition coefficient (K) of each series. As with other animals, potency was directly related to the lipid solubility of these agents so that, for example, the ID{sub 50} for methanol was 1,000 mmol (K=0.12) whereas it was 0.17 mmol for heptanol (K=3,000). The alcohols were about 20 times more potent than the alkanes even though the latter were about 10 times more lipid soluble than the alcohols. In spite of these differences, the cut-off point was at C{sub 9} in the two series.

  10. Pain fiber anesthetic reduces brainstem Fos after tooth extraction.

    Science.gov (United States)

    Badral, B; Davies, A J; Kim, Y H; Ahn, J S; Hong, S D; Chung, G; Kim, J S; Oh, S B

    2013-11-01

    We recently demonstrated that pain-sensing neurons in the trigeminal system can be selectively anesthetized by co-application of QX-314 with the TRPV1 receptor agonist, capsaicin (QX cocktail). Here we examined whether this new anesthetic strategy can block the neuronal changes in the brainstem following molar tooth extraction in the rat. Adult male Sprague-Dawley rats received infiltration injection of anesthetic 10 min prior to lower molar tooth extraction. Neuronal activation was determined by immunohistochemistry for the proto-oncogene protein c-Fos in transverse sections of the trigeminal subnucleus caudalis (Sp5C). After tooth extraction, c-Fos-like immunoreactivity (Fos-LI) detected in the dorsomedial region of bilateral Sp5C was highest at 2 hrs (p tooth extraction; reduced Fos-LI was also observed with the conventional local anesthetic lidocaine. Pulpal anesthesia by infiltration injection was confirmed by inhibition of the jaw-opening reflex in response to electrical tooth pulp stimulation. Our results suggest that the QX cocktail anesthetic is effective in reducing neuronal activation following tooth extraction. Thus, a selective pain fiber 'nociceptive anesthetic' strategy may provide an effective local anesthetic option for dental patients in the clinic.

  11. Blood profiles in unanesthetized and anesthetized guinea pigs (Cavia porcellus).

    Science.gov (United States)

    Williams, Wendy R; Johnston, Matthew S; Higgins, Sarah; Izzo, Angelo A; Kendall, Lon V

    2016-01-01

    The guinea pig is a common animal model that is used in biomedical research to study a variety of systems, including hormonal and immunological responses, pulmonary physiology, corticosteroid response and others. However, because guinea pigs are evolutionarily a prey species, they do not readily show behavioral signs of disease, which can make it difficult to detect illness in a laboratory setting. Minimally invasive blood tests, such as complete blood counts and plasma biochemistry assays, are useful in both human and veterinary medicine as an initial diagnostic technique to rule in or rule out systemic illness. In guinea pigs, phlebotomy for such tests often requires that the animals be anesthetized first. The authors evaluated hematological and plasma biochemical effects of two anesthetic agents that are commonly used with guinea pigs in a research setting: isoflurane and a combination of ketamine and xylazine. Hematological and plasma biochemical parameters were significantly different when guinea pigs were under either anesthetic, compared to when they were unanesthetized. Plasma proteins, liver enzymes, white blood cells and red blood cells appeared to be significantly altered by both anesthetics, and hematological and plasma biochemical differences were greater when guinea pigs were anesthetized with the combination of ketamine and xylazine than when they were anesthetized with isoflurane. Overall these results indicate that both anesthetics can significantly influence hematological and plasma biochemical parameters in guinea pigs.

  12. Can anesthetic treatment worsen outcome in status epilepticus?

    Science.gov (United States)

    Sutter, Raoul; Kaplan, Peter W

    2015-08-01

    Status epilepticus refractory to first-line and second-line antiepileptic treatments challenges neurologists and intensivists as mortality increases with treatment refractoriness and seizure duration. International guidelines advocate anesthetic drugs, such as continuously administered high-dose midazolam, propofol, and barbiturates, for the induction of therapeutic coma in patients with treatment-refractory status epilepticus. The seizure-suppressing effect of anesthetic drugs is believed to be so strong that some experts recommend using them after benzodiazepines have failed. Although the rationale for the use of anesthetic drugs in patients with treatment-refractory status epilepticus seems clear, the recommendation of their use in treating status epilepticus is based on expert opinions rather than on strong evidence. Randomized trials in this context are lacking, and recent studies provide disturbing results, as the administration of anesthetics was associated with poor outcome independent of possible confounders. This calls for caution in the straightforward use of anesthetics in treating status epilepticus. However, there are still more questions than answers, and current evidence for the adverse effects of anesthetic drugs in patients with status epilepticus remains too limited to advocate a change of treatment algorithms. In this overview, the rationale and the conflicting clinical implications of anesthetic drugs in patients with treatment-refractory status epilepticus are discussed, and remaining questions are elaborated. This article is part of a Special Issue entitled "Status Epilepticus".

  13. Comparison of anesthetic agents in the sea otter

    Energy Technology Data Exchange (ETDEWEB)

    Williams, T.D.; Kocher, F.H.

    1978-01-01

    Five anesthetic agents (CI744, etorphine, fentanyl, ketamine hydrochloride, and halothane) were tested to establish the dosage of a safe, effective, short-acting anesthetic for use in the sea otter. Etorphine, at a dosage of 0.75 mg per adult otter and used in conjunction with diazepam, at a dosage of 1.25 mg per adult otter, met most of the requirements for use under field conditions. Halothane, administered through an anesthetic machine, proved to be effective for use in a veterinary hospital.

  14. Challenges Encountered Using Ophthalmic Anesthetics in Space Medicine

    Science.gov (United States)

    Bayuse, T.; Law, J.; Alexander, D.; Moynihan, S.; LeBlanc, C.; Langford, K.; Magalhaes, L.

    2015-01-01

    On orbit, ophthalmic anesthetics are used for tonometry and off-nominal corneal examinations. Proparacaine has been flown traditionally. However, the manufacturers recently changed its storage requirements from room temperature storage to refrigerated storage to preserve stability and prolong the shelf-life. Since refrigeration on orbit is not readily available and there were stability concerns about flying proparacaine unrefrigerated, tetracaine was selected as an alternative ophthalmic anesthetic in 2013. We will discuss the challenges encountered flying and using these anesthetics on the International Space Station.

  15. Local anesthetics: dentistry's most important drugs, clinical update 2006.

    Science.gov (United States)

    Malamed, Stanley F

    2006-12-01

    Local anesthetics are the safest most effective drugs in medicine for the control and management of pain. They also represent the most important drugs in dentistry. Today, dentistry has a spectrum of local anesthetics that permit pain control to be tailored to the specific needs of the patient: short-, intermediate-, and long-acting drugs. Bupivacaine has become a standard part of the armamentarium for postsurgical pain control while articaine has become the second-most used local anesthetic in the United States since its introduction in 2000. Despite an increase in anecdotal reports of paresthesia since articaine's introduction there is yet, no supporting scientific evidence.

  16. Understanding Financial Market Volatility

    NARCIS (Netherlands)

    A. Opschoor (Anne)

    2014-01-01

    markdownabstract__Abstract__ Volatility has been one of the most active and successful areas of research in time series econometrics and economic forecasting in recent decades. Loosely speaking, volatility is defined as the average magnitude of fluctuations observed in some phenomenon over time. Wi

  17. Benzocaine-loaded polymeric nanocapsules: study of the anesthetic activities.

    Science.gov (United States)

    De Melo, Nathalie Ferreira Silva; De Araújo, Daniele Ribeiro; Grillo, Renato; Moraes, Carolina Morales; De Matos, Angélica Prado; de Paula, Eneida; Rosa, André Henrique; Fraceto, Leonardo Fernandes

    2012-03-01

    This paper describes a comparison of different polymeric nanocapsules (NCs) prepared with the polymers poly(D,L-lactide-co-glycolide), poly(L-lactide) (PLA), and poly(ε-caprolactone) and used as carrier systems for the local anesthetic (LA) benzocaine (BZC). The systems were characterized and their anesthetic activities investigated. The results showed particle size distributions with polydispersity indices below 0.135, average diameters up to 120 nm, zeta potentials up to -30 mV, and entrapment efficiencies around 70%. Formulations of BZC using the polymeric NCs presented slower release profiles, compared with that of free BZC. Slowest release (release constant, k = 0.0016 min(-1)) was obtained using the PLA NC system. Pharmacological evaluation showed that encapsulation of BZC in PLA NCs prolonged its anesthetic action. This new formulation could potentially be used in future applications involving the gradual release of local anesthetics (LAs).

  18. Trigeminal nerve injury associated with injection of local anesthetics

    DEFF Research Database (Denmark)

    Hillerup, Søren; Jensen, Rigmor H.; Ersbøll, Bjarne Kjær

    2011-01-01

    , prilocaine 3 percent, and articaine 4 percent sold in cartridges. Results. The study results showed a highly significant overrepresentation of NSDs associated with articaine 4 percent, in particular with mandibular blocks. Conclusions. The distribution of NSDs was disproportionate to the market share......Background. The authors used comprehensive national registry and clinical data to conduct a study of adverse drug reactions (ADRs), in particular neurosensory disturbance (NSD), associated with local anesthetics used in dentistry. Methods. The study included data sets of annual sales of local...... anesthetics (from 1995 through 2007), 292 reports to the Danish Medicines Agency, Copenhagen, Denmark, of adverse reactions to local anesthetic drugs, and a clinical sample of 115 patients with NSD associated with local anesthetics. The authors assessed lidocaine 2 percent, mepivacaine 2 percent and 3 percent...

  19. Cardiovascular effects of tramadol in dogs anesthetized with sevoflurane.

    Science.gov (United States)

    Itami, Takaharu; Tamaru, Naomichi; Kawase, Kodai; Ishizuka, Tomohito; Tamura, Jun; Miyoshi, Kenjirou; Umar, Mohammed A; Inoue, Hiroki; Yamashita, Kazuto

    2011-12-01

    Cardiovascular effects of tramadol were evaluated in dogs anesthetized with sevoflurane. Six beagle dogs were anesthetized twice at 7 days interval. The minimum alveolar concentration (MAC) of sevoflurane was earlier determined in each dog. The dogs were then anesthetized with sevoflurane at 1.3 times of predetermined individual MAC and cardiovascular parameters were evaluated before (baseline) and after an intravenous injection of tramadol (4 mg/kg). The administration of tramadol produced a transient and mild increase in arterial blood pressure (ABP) (P=0.004) with prolonged increase in systemic vascular resistance (SVR) (Ppressure, right atrial pressure and pulmonary capillary wedge pressure. In conclusion, the administration of tramadol produces a prolonged peripheral vascular constriction in dogs anesthetized with sevoflurane, which is accompanied with a transient and mild increase in arterial blood pressure. It also indicated that the degree of vasoconstriction might depend on the plasma concentration of tramadol.

  20. Anesthetic issues for robotic cardiac surgery

    Directory of Open Access Journals (Sweden)

    Wendy K Bernstein

    2015-01-01

    Full Text Available As innovative technology continues to be developed and is implemented into the realm of cardiac surgery, surgical teams, cardiothoracic anesthesiologists, and health centers are constantly looking for methods to improve patient outcomes and satisfaction. One of the more recent developments in cardiac surgical practice is minimally invasive robotic surgery. Its use has been documented in numerous publications, and its use has proliferated significantly over the past 15 years. The anesthesiology team must continue to develop and perfect special techniques to manage these patients perioperatively including lung isolation techniques and transesophageal echocardiography (TEE. This review article of recent scientific data and personal experience serves to explain some of the challenges, which the anesthetic team must manage, including patient and procedural factors, complications from one-lung ventilation (OLV including hypoxia and hypercapnia, capnothorax, percutaneous cannulation for cardiopulmonary bypass, TEE guidance, as well as methods of intraoperative monitoring and analgesia. As existing minimally invasive techniques are perfected, and newer innovations are demonstrated, it is imperative that the cardiothoracic anesthesiologist must improve and maintain skills to guide these patients safely through the robotic procedure.

  1. Anesthetic Management of a Patient With Jarcho-Levin Syndrome

    Directory of Open Access Journals (Sweden)

    Gamze Küçükosman

    2016-06-01

    Full Text Available Jarcho-Levin syndrome (JLS is a rare disease involving costovertebral anomalies and is accompanied by hydrocephalus, neural tube defect, and cardiac, renal and gastrointestinal problems. Due to respiratory system pathologies, there is a high mortality rate at young ages. Due to its rarity and little information in the literature related to anesthetic practice for this syndrome, we present our anesthetic experience of inguinal hernia surgery in a patient with JLS.

  2. Anesthetic Management of a Patient with Cornelia De Lange Syndrome

    OpenAIRE

    Takeshita, Takahisa; Akita, Susumu; Kawahara, Michio

    1987-01-01

    Cornelia de Lange syndrome presents various problems for anesthetic management, which include anatomical anomalies of face and extremities, cardiopulmonary and endocrine disorders, renal dysfunction, epileptic EEG waves, and mental retardation. The choice of anesthetic procedure must be carefully considered in view of these abnormalities. We administered halothane anesthesia to an 11-year-old child with this syndrome who needed dental treatment. Anesthesia and postoperative course were uneven...

  3. Activation of TRPA1 by membrane permeable local anesthetics

    Directory of Open Access Journals (Sweden)

    Kronewald Sergej

    2011-08-01

    Full Text Available Abstract Background Low concentrations of local anesthetics (LAs suppress cellular excitability by inhibiting voltage-gated Na+ channels. In contrast, LAs at high concentrations can be excitatory and neurotoxic. We recently demonstrated that LA-evoked activation of sensory neurons is mediated by the capsaicin receptor TRPV1, and, to a lesser extent by the irritant receptor TRPA1. LA-induced activation and sensitization of TRPV1 involves a domain that is similar, but not identical to the vanilloid-binding domain. Additionally, activation of TRPV1 by LAs involves PLC and PI(4,5P2-signalling. In the present study we aimed to characterize essential structural determinants for LA-evoked activation of TRPA1. Results Recombinant rodent and human TRPA1 were expressed in HEK293t cells and investigated by means of whole-cell patch clamp recordings. The LA lidocaine activates TRPA1 in a concentration-dependent manner. The membrane impermeable lidocaine-derivative QX-314 is inactive when applied extracellularly. Lidocaine-activated TRPA1-currents are blocked by the TRPA1-antagonist HC-030031. Lidocaine is also an inhibitor of TRPA1, an effect that is more obvious in rodent than in human TRPA1. This species-specific difference is linked to the pore region (transmembrane domain 5 and 6 as described for activation of TRPA1 by menthol. Unlike menthol-sensitivity however, lidocaine-sensitivity is not similarly determined by serine- and threonine-residues within TM5. Instead, intracellular cysteine residues known to be covalently bound by reactive TRPA1-agonists seem to mediate activation of TRPA1 by LAs. Conclusions The structural determinants involved in activation of TRPA1 by LAs are disparate from those involved in activation by menthol or those involved in activation of TRPV1 by LAs.

  4. Water solvent and local anesthetics: A computational study

    Science.gov (United States)

    Bernardi, R. C.; Gomes, D. E. B.; Pascutti, P. G.; Ito, A. S.; Taft, C. A.; Ota, A. T.

    There are various experimental studies regarding the toxicity and the time of action of local anesthetics, which contain general insights about their pharmacological and physicochemical properties. Although a detailed microscopic analysis of the local anesthetics would contribute to understanding these properties, there are relatively few theoretical studies about these molecules. In this article, we present the results from calculations performed for three local anesthetics: tetracaine, procaine, and lidocaine, both in their charged and uncharged forms, in aqueous environment. We have used the density functional theory and molecular dynamics simulations to study the structural characteristics of these compounds. The radial distribution function g(r) was used to examine the structure of water molecules surrounding different regions of the local anesthetics. We demonstrated the nonhomogeneous character of the anesthetics with respect to their affinity to water solvent molecules as well as the modifications in their affinity to water caused by changes in their charge state. We also observed that the biological potency of the anesthetics is more related to the behavior of specific groups within the molecule, which are responsible for the interaction with the lipid phase of membranes, rather than the general properties of the molecule as a whole.

  5. Effects of anesthetic compounds on responses of earthworms to electrostimulation.

    Science.gov (United States)

    Podolak-Machowska, Agnieszka; Kostecka, Joanna; Librowski, Tadeusz; Santocki, Michal; Bigaj, Janusz; Plytycz, Barbara

    2014-01-01

    Earthworms play an important role in biomedical research, and some surgical procedures require anesthesia. Anesthetic treatments used so far usually induce convulsive body movements connected with extrusion of coelomocyte-containing coelomic fluid that may affect experimental results. Extensive movements connected with the expulsion of coelomic fluid are exploited by immunologists as a method of harvesting immunocompetent coelomocytes from worms subjected to mild electrostimulation (4.5V). The aim of the investigations was to find anesthetic drugs without unintentional coelomocyte depletion. Experiments were performed on adult specimens of Dendrobaena veneta, the coelomocytes of which consist of amoebocytes and riboflavin-storing eleocytes. Earthworm mobility was filmed and extrusion of coelomocytes was quantified by detection of eleocyte-derived riboflavin in immersion fluid. Treatments included earthworms (1) immersed either in physiological saline (controls) or in a solution of one of the tested anesthetic drugs; (2) electrostimulated immediately after anesthesia, and (3) electrostimulated a second time after a 1-hour recovery period. The well-established fish and amphibian anesthetic agent MS-222 induced coelomocyte expulsion. In contrast, solutions of the mammalian local anesthetic drug, prilocaine hydrochloride (0.25-0.5%, 5-10 min) caused temporal earthworm immobilization followed by recovery, thus showing utility as an efficient earthworm anesthetic.

  6. Atomic determinants of state-dependent block of sodium channels by charged local anesthetics and benzocaine.

    Science.gov (United States)

    Tikhonov, Denis B; Bruhova, Iva; Zhorov, Boris S

    2006-11-13

    Molecular modeling predicts that a local anesthetic (LA) lidocaine binds to the resting and open Na(v)1.5 in different modes, interacting with LA-sensing residues known from experiments. Besides the major pathway via the open activation gate, LAs can reach the inner pore via a "sidewalk" between D3S6, D4S6, and D3P. The ammonium group of a cationic LA binds in the focus of the pore-helices macrodipoles, which also stabilize a Na(+) ion chelated by two benzocaine molecules. The LA's cationic group and a Na(+) ion in the selectivity filter repel each other suggesting that the Na(+) depletion upon slow inactivation would stabilize a LA, while a LA would stabilize slow-inactivated states.

  7. Idiosyncratic Volatility Puzzle

    DEFF Research Database (Denmark)

    Aslanidis, Nektarios; Christiansen, Charlotte; Lambertides, Neophytos;

    from a large pool of macroeconomic and Önancial variables. Cleaning for macro-Önance e§ects reverses the puzzling negative relation between returns and idiosyncratic volatility documented previously. Portfolio analysis shows that the e§ects from macro-Önance factors are economically strong......In this paper, we scrutinize the cross-sectional relation between idiosyncratic volatility and stock returns. As a novelty, the idiosyncratic volatility is obtained by conditioning upon macro-Önance factors as well as upon traditional asset pricing factors. The macro-Önance factors are constructed...

  8. Pattern recognition analysis of proton nuclear magnetic resonance spectra of brain tissue extracts from rats anesthetized with propofol or isoflurane.

    Directory of Open Access Journals (Sweden)

    Hiroshi Kawaguchi

    Full Text Available BACKGROUND: General anesthesia is routinely used as a surgical procedure and its safety has been endorsed by clinical outcomes; however, its effects at the molecular level have not been elucidated. General anesthetics influence glucose metabolism in the brain. However, the effects of anesthetics on brain metabolites other than those related to glucose have not been well characterized. We used a pattern recognition analysis of proton nuclear magnetic resonance spectra to visualize the changes in holistic brain metabolic phenotypes in response to the widely used intravenous anesthetic propofol and the volatile anesthetic isoflurane. METHODOLOGY/PRINCIPAL FINDINGS: Rats were randomized into five groups (n = 7 each group. Propofol and isoflurane were administered to two groups each, for 2 or 6 h. The control group received no anesthesia. Brains were removed directly after anesthesia. Hydrophilic compounds were extracted from excised whole brains and measured by proton nuclear magnetic resonance spectroscopy. All spectral data were processed and analyzed by principal component analysis for comparison of the metabolite profiles. Data were visualized by plotting principal component (PC scores. In the plots, each point represents an individual sample. The propofol and isoflurane groups were clustered separately on the plots, and this separation was especially pronounced when comparing the 6-h groups. The PC scores of the propofol group were clearly distinct from those of the control group, particularly in the 6-h group, whereas the difference in PC scores was more subtle in the isoflurane group and control groups. CONCLUSIONS/SIGNIFICANCE: The results of the present study showed that propofol and isoflurane exerted differential effects on holistic brain metabolism under anesthesia.

  9. A hypothesis on the origin and evolution of the response to inhaled anesthetics

    OpenAIRE

    Sonner, James M.

    2008-01-01

    An evolutionary narrative explaining why organisms respond to inhaled anesthetics is proposed. It is conjectured that organisms today respond to inhaled anesthetics because their ion channels are sensitive to inhaled anesthetics by virtue of common descent from ancestral, anesthetic-sensitive ion channels in one-celled organisms (i.e., that the response to anesthetics did not arise as an adaptation of the nervous system, but rather of ion channels that preceded the origin of multicellularity)...

  10. 麻醉药的心脑保护作用:最新临床研究证据及展望%Cardio-neuroprotection of anesthetic agents: recent clinical evidence and perspectives

    Institute of Scientific and Technical Information of China (English)

    李新; 熊利泽

    2015-01-01

    Background The cardio-neuroprotective effect of anesthetics has been widely concerned but still controversial.Although strong preclinical data support that anesthetics could attenuate ischemic/hypoxic myocardial and cerebral injury,confirmative conclusions have not been demonstrated from clinical studies.We reviewed clinical trials in recent years(especially randomized controlled trials) on cardio-neuroprotection of commonly used anesthetic agents (volatile anesthetics:isoflurane,sevoflurane,intravenous anesthetics:propofol,dexmedetomidine).Among the mostly studied anesthetics that reveal the property of cardio-neuroprotection,ether-derived volatile anesthetics have shown more promising potentials than intravenous anesthetics,especially in cardiac surgeries.The cardio-neuroprotection of intravenous anesthetic dexmedetomidine was validated in heart surgery by randomized controlled trial with large sample.However,the neuroprotection of anesthetic agents is controversial,and there's lack of simple and objective evaluation indicators for it.Thus,large-scale,multicenter clinical trials are necessary in the future.%麻醉药的心脑保护作用一直广受关注,但仍存在一些争议.尽管多数临床前研究发现常用麻醉药能减轻缺血/缺氧性心脑损伤,但临床研究却未得到确定性结论.综述近年来关于麻醉药心脑保护作用的临床研究,尤其是随机对照研究,结果表明,多数常用的麻醉药(吸入性麻醉药异氟醚、七氟醚,静脉麻醉药丙泊酚、右美托咪定等)均表现出一定的心脏保护作用,其中氟烷类吸入性麻醉药较静脉麻醉药效果更明显,可显著减轻心脏手术患者的心肌损伤.静脉麻醉药中,右美托咪定对心脏手术患者的心肌保护作用在大样本临床研究中得到验证.麻醉药的脑保护作用存在较大争议,也缺少简单、客观的疗效评价指标,还应开展大规模、多中心的临床研究.

  11. Interference of anesthetics in blood alcohol analysis by HS-GC-FID: A case report.

    Science.gov (United States)

    Monteiro, C; Proença, P; Tavares, C; Castañera, A; Corte Real, F

    2016-08-01

    One of the techniques most widely used in ethanol analysis in forensic laboratories is undoubtedly the headspace gas chromatography with flame-ionization detection (HS-GC-FID) since the determination of this substance is carried out directly, without the need for additional purification procedures, which leads to increased productivity. This is a very important factor due to the high number of alcohol analysis requested to these laboratories. The presence of other volatile substances can cause a problem given the fact that they can be interferents in ethanol analysis by HS-GC-FID, which can have legal consequences related with driving under the influence of alcohol. The authors report a case of a routine analysis by HS-GC-FID for the determination of ethanol of a driver who has suffered an accident in which the use of two chromatographic columns with different polarities was essential to obtain an unequivocally identification of this substance in presence of an interfering volatile anesthetic administered in the hospital. The method was validated according to international recommendations before being introduced into routine laboratory in terms of selectivity, limits of detection (LOD), limits of quantification (LOQ), linearity, repeatability, intermediate precision, accuracy, robustness and carryover.

  12. The effect of sub-anesthetic and anesthetic ketamine on water maze memory acquisition, consolidation and retrieval.

    Science.gov (United States)

    Moosavi, Maryam; Yadollahi Khales, Golnaz; Rastegar, Karim; Zarifkar, Asadollah

    2012-02-29

    Ketamine, a non-selective inhibitor of NMDA (N-methyl-D-aspartate) channels is used in anesthetic or sub-anesthetic doses to induce analgesia, amnesia, to suppress fear, anxiety and depression. Although the ketamine's effect on memory acquisition is known, its effects on other aspects of memory are controversial. Morris water maze is a task which assesses spatial learning and memory. This study was aimed to assess the ketamine's differential effect on water maze memory acquisition, consolidation and retrieval. Male Sprague-Dawley rats (250-350 g) were trained in water maze single training session. 24h later a probe trial which was consisted of a single trial without platform was done. To assess the effect of ketamine on water maze memory acquisition it was administered before training; to assess its effect on memory consolidation it was administered immediately after training and to assess its effect on memory retrieval it was injected before probe trial. Ketamine both in sub-anesthetic and anesthetic doses impaired water maze memory acquisition, its anesthetic dose but not sub-anesthetic dose impaired memory consolidation and on retrieval stage, both doses deteriorated memory retrieval. It seems that NMDA receptor activity is not just necessary during water maze memory acquisition but also their post-learning reactivation is required to maintain memory consolidation and retrieval.

  13. On guidance and volatility

    NARCIS (Netherlands)

    Billings, M.B.; Jennings, R.; Lev, B.

    2013-01-01

    Survey evidence suggests that managers voluntarily disclose information, particularly earnings guidance, with an aim toward dampening share price volatility. Yet, consultants and influential institutions advise against providing guidance — citing fears of litigation and market penalties associated w

  14. It’s all about volatility of volatility

    DEFF Research Database (Denmark)

    Grassi, Stefano; Santucci de Magistris, Paolo

    2015-01-01

    for the realized volatility series. It emerges that during the recent financial crisis the relative weight of the daily component dominates over the monthly term. The estimates of the two factor stochastic volatility model suggest that the change in the dynamic structure of the realized volatility during...... the financial crisis is due to the increase in the volatility of the persistent volatility term. A set of Monte Carlo simulations highlights the robustness of the methodology adopted in tracking the dynamics of the parameters....

  15. Non-volatile memories

    CERN Document Server

    Lacaze, Pierre-Camille

    2014-01-01

    Written for scientists, researchers, and engineers, Non-volatile Memories describes the recent research and implementations in relation to the design of a new generation of non-volatile electronic memories. The objective is to replace existing memories (DRAM, SRAM, EEPROM, Flash, etc.) with a universal memory model likely to reach better performances than the current types of memory: extremely high commutation speeds, high implantation densities and retention time of information of about ten years.

  16. Recognition of local anesthetics by alphabeta+ T cells.

    Science.gov (United States)

    Zanni, M P; von Greyerz, S; Hari, Y; Schnyder, B; Pichler, W J

    1999-02-01

    Patients with drug allergy show a specific immune response to drugs. Chemically nonreactive drugs like, for example, local anesthetics are directly recognized by alphabeta+ T cells in an HLA-DR restricted way, as neither drug metabolism nor protein processing is required for T cell stimulation. In this study we identified some of the structural requirements that determine cross-reactivity of T cells to local anesthetics, with the aim to improve the molecular basis for the selection of alternatives in individuals sensitized to a certain local anesthetic and to better understand presentation and T cell recognition of these drugs. Fifty-five clones (52 lidocaine specific, three mepivacaine specific from two allergic donors) were analyzed. Stimulatory compounds induced a down-regulation of the T cell receptor, demonstrating that these non-peptide antigens are recognized by the T cell receptor itself. A consistent cross-reactivity between lidocaine and mepivacaine was found, as all except one lidocaine specific clone proliferated to both drugs tested. Sixteen chemically related local anesthetics (including ester local anesthetics, OH- and desalkylated metabolites) were used to identify structural requirements for T cell recognition. Each of the four clones examined in detail was uniquely sensitive to changes in the structures of the local anesthetic: clone SFT24, i.e., did not recognize any of the tested OH- or desalkylated metabolites, while the clone OFB2 proliferated to all OH-metabolites and other differently modified molecules. The broadly reactive clone OFB2 allowed us to propose a model, suggesting that the structure of the amine side chain of local anesthetics is essential for recognition by the T cell receptor.

  17. From micro- to nanostructured implantable device for local anesthetic delivery

    Directory of Open Access Journals (Sweden)

    Zorzetto L

    2016-06-01

    Full Text Available Laura Zorzetto,1 Paola Brambilla,1 Elena Marcello,1 Nora Bloise,2 Manuela De Gregori,3 Lorenzo Cobianchi,4,5 Andrea Peloso,4,5 Massimo Allegri,6 Livia Visai,2,7 Paola Petrini1 1Department of Chemistry, Materials and Chemical Engineering ‘G. Natta’, Politecnico di Milano, Milan, 2Department of Molecular Medicine, Centre for Health Technologies (CHT, INSTM UdR of Pavia, University of Pavia, 3Pain Therapy Service, IRCCS Foundation Policlinico San Matteo Pavia, Pavia, 4General Surgery Department, IRCCS Foundation Policlinico San Matteo, Pavia, 5Departments of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, Pavia, 6Department of Surgical Sciences, University of Parma, Parma, 7Department of Occupational Medicine, Toxicology and Environmental Risks, S. Maugeri Foundation, IRCCS, Lab of Nanotechnology, Pavia, Italy Abstract: Local anesthetics block the transmission of painful stimuli to the brain by acting on ion channels of nociceptor fibers, and find application in the management of acute and chronic pain. Despite the key role they play in modern medicine, their cardio and neurotoxicity (together with their short half-life stress the need for developing implantable devices for tailored local drug release, with the aim of counterbalancing their side effects and prolonging their pharmacological activity. This review discusses the evolution of the physical forms of local anesthetic delivery systems during the past decades. Depending on the use of different biocompatible materials (degradable polyesters, thermosensitive hydrogels, and liposomes and hydrogels from natural polymers and manufacturing processes, these systems can be classified as films or micro- or nanostructured devices. We analyze and summarize the production techniques according to this classification, focusing on their relative advantages and disadvantages. The most relevant trend reported in this work highlights the effort of moving from microstructured

  18. Oil and stock market volatility: A multivariate stochastic volatility perspective

    Energy Technology Data Exchange (ETDEWEB)

    Vo, Minh, E-mail: minh.vo@metrostate.edu

    2011-09-15

    This paper models the volatility of stock and oil futures markets using the multivariate stochastic volatility structure in an attempt to extract information intertwined in both markets for risk prediction. It offers four major findings. First, the stock and oil futures prices are inter-related. Their correlation follows a time-varying dynamic process and tends to increase when the markets are more volatile. Second, conditioned on the past information, the volatility in each market is very persistent, i.e., it varies in a predictable manner. Third, there is inter-market dependence in volatility. Innovations that hit either market can affect the volatility in the other market. In other words, conditioned on the persistence and the past volatility in their respective markets, the past volatility of the stock (oil futures) market also has predictive power over the future volatility of the oil futures (stock) market. Finally, the model produces more accurate Value-at-Risk estimates than other benchmarks commonly used in the financial industry. - Research Highlights: > This paper models the volatility of stock and oil futures markets using the multivariate stochastic volatility model. > The correlation between the two markets follows a time-varying dynamic process which tends to increase when the markets are more volatile. > The volatility in each market is very persistent. > Innovations that hit either market can affect the volatility in the other market. > The model produces more accurate Value-at-Risk estimates than other benchmarks commonly used in the financial industry.

  19. Liquid general anesthetics lower critical temperatures in plasma membrane vesicles

    CERN Document Server

    Gray, Ellyn; Machta, Benjamin B; Veatch, Sarah L

    2013-01-01

    A large and diverse array of small hydrophobic molecules induce general anesthesia. Their efficacy as anesthetics has been shown to correlate both with their affinity for a hydrophobic environment and with their potency in inhibiting certain ligand gated ion channels. Here we explore the effects that n-alcohols and other liquid anesthetics have on the two-dimensional miscibility critical point observed in cell derived giant plasma membrane vesicles (GPMVs). We show that anesthetics depress the critical temperature (Tc) of these GPMVs without strongly altering the ratio of the two liquid phases found below Tc. The magnitude of this affect is consistent across n-alcohols when their concentration is rescaled by the median anesthetic concentration (AC50) for tadpole anesthesia, but not when plotted against the overall concentration in solution. At AC50 we see a 4{\\deg}C downward shift in Tc, much larger than is typically seen in the main chain transition at these anesthetic concentrations. GPMV miscibility critic...

  20. Effect of general anesthetics on the developing brain

    Directory of Open Access Journals (Sweden)

    S Velayudha Reddy

    2012-01-01

    Full Text Available Studies on rodents and subhuman primates suggest that prolonged exposure to general anesthetics may induce widespread neuronal cell death and neurological sequelae; seriously questioning the safety of pediatric anesthesia. This review presents recent developments in this rapidly emerging field. There is mounting and convincing preclinical evidence in rodents and nonhuman primates that anesthetics in common clinical use are neurotoxic to the developing brain in vitro and cause long-term neurobehavioral abnormalities in vivo. Prior to the publication of animal data and after the publication of animal data, there are several human cohort studies that demonstrate the association of poor neurodevelopmental outcome in neonates, who underwent major surgery during their neonatal period. This review summarizes our present understanding of some of the key components responsible for anesthesia-induced neuroapoptosis and offers some of neuroprotective strategies that could be beneficial as adjunct therapy in preventing anesthesia-induced death of developing neurons in the neonates. A randomized literature search was carried out using search words apoptosis, general anesthetics, and developing brain from 1979 to 2011 for effects of general anesthetics on developing brain in PUBMED and relevant published literature reviewed. General anesthetics may produce neurotoxicity and enduring cognitive impairment in young and aged animals, but the issue has not been adequately studied in humans. It is premature to recommend a change clinical practice based on the present data.

  1. Intravenous sub-anesthetic ketamine for perioperative analgesia.

    Science.gov (United States)

    Gorlin, Andrew W; Rosenfeld, David M; Ramakrishna, Harish

    2016-01-01

    Ketamine, an N-methyl-d-aspartate antagonist, blunts central pain sensitization at sub-anesthetic doses (0.3 mg/kg or less) and has been studied extensively as an adjunct for perioperative analgesia. At sub-anesthetic doses, ketamine has a minimal physiologic impact though it is associated with a low incidence of mild psychomimetic symptoms as well as nystagmus and double vision. Contraindications to its use do exist and due to ketamine's metabolism, caution should be exercised in patients with renal or hepatic dysfunction. Sub-anesthetic ketamine improves pain scores and reduces perioperative opioid consumption in a broad range of surgical procedures. In addition, there is evidence that ketamine may be useful in patients with opioid tolerance and for preventing chronic postsurgical pain.

  2. Intravenous sub-anesthetic ketamine for perioperative analgesia

    Directory of Open Access Journals (Sweden)

    Andrew W Gorlin

    2016-01-01

    Full Text Available Ketamine, an N-methyl-d-aspartate antagonist, blunts central pain sensitization at sub-anesthetic doses (0.3 mg/kg or less and has been studied extensively as an adjunct for perioperative analgesia. At sub-anesthetic doses, ketamine has a minimal physiologic impact though it is associated with a low incidence of mild psychomimetic symptoms as well as nystagmus and double vision. Contraindications to its use do exist and due to ketamine′s metabolism, caution should be exercised in patients with renal or hepatic dysfunction. Sub-anesthetic ketamine improves pain scores and reduces perioperative opioid consumption in a broad range of surgical procedures. In addition, there is evidence that ketamine may be useful in patients with opioid tolerance and for preventing chronic postsurgical pain.

  3. Costs of anesthetics and other drugs in anesthesia

    Directory of Open Access Journals (Sweden)

    Majstorović Branislava M.

    2012-01-01

    Full Text Available Introduction. Drugs are real and transparent costs of treatment, which are subject to constant monitoring and changes. The study was aimed at measuring and analyzing consumption of anesthetics and other drugs in anesthesia in the Clinical Centre of Serbia. Material and Methods. This paper is part of a five-year (2005-2009, academic, pharmacoeconomic retrospective-prospective study (the 4th phase. We calculated the costs of anesthetics and other drugs in all anesthetized patients at the Institute of Anesthesia and Reanimation, Clinical Center of Serbia in 2006. The data, obtained from the Clinical Centre of Serbia Database, were analyzed by descriptive statistical methods using computer program Microsoft Office Excel 2003 and the Statistical Package for the Social Sciences (SPSS for Windows. Results. The amount of money spent for the application of 33,187 general and 16,394 local anesthesia and 20,614 anesthesiology procedures was 83,322,046.36 RSD (Euros 1,054,705.4, which was 5.93% of the funds allocated for all drugs used at the Clinical Center of Serbia. Of the total fund for drugs, 57.8% was spent for anesthetics (local anesthetics 1.2% and muscle relaxants, whereas 42.2% was spent for other drugs in anesthesia. The highest amount was spent at the Emergency Center (35.8%, then at the Cardio-surgery (11.9% and the Neurosurgery (10.9% because of the large number and length of surgical interventions. Conclusion. There is no space for rationalizing the costs of anesthetics and other drugs in anesthesia.

  4. Volatiles in protoplanetary disks

    CERN Document Server

    Pontoppidan, Klaus M; Bergin, Edwin A; Brittain, Sean; Marty, Bernard; Mousis, Olvier; Oberg, Karin L

    2014-01-01

    Volatiles are compounds with low sublimation temperatures, and they make up most of the condensible mass in typical planet-forming environments. They consist of relatively small, often hydrogenated, molecules based on the abundant elements carbon, nitrogen and oxygen. Volatiles are central to the process of planet formation, forming the backbone of a rich chemistry that sets the initial conditions for the formation of planetary atmospheres, and act as a solid mass reservoir catalyzing the formation of planets and planetesimals. This growth has been driven by rapid advances in observations and models of protoplanetary disks, and by a deepening understanding of the cosmochemistry of the solar system. Indeed, it is only in the past few years that representative samples of molecules have been discovered in great abundance throughout protoplanetary disks - enough to begin building a complete budget for the most abundant elements after hydrogen and helium. The spatial distributions of key volatiles are being mapped...

  5. Stochastic volatility selected readings

    CERN Document Server

    Shephard, Neil

    2005-01-01

    Neil Shephard has brought together a set of classic and central papers that have contributed to our understanding of financial volatility. They cover stocks, bonds and currencies and range from 1973 up to 2001. Shephard, a leading researcher in the field, provides a substantial introduction in which he discusses all major issues involved. General Introduction N. Shephard. Part I: Model Building. 1. A Subordinated Stochastic Process Model with Finite Variance for Speculative Prices, (P. K. Clark). 2. Financial Returns Modelled by the Product of Two Stochastic Processes: A Study of Daily Sugar Prices, 1961-7, S. J. Taylor. 3. The Behavior of Random Variables with Nonstationary Variance and the Distribution of Security Prices, B. Rosenberg. 4. The Pricing of Options on Assets with Stochastic Volatilities, J. Hull and A. White. 5. The Dynamics of Exchange Rate Volatility: A Multivariate Latent Factor ARCH Model, F. X. Diebold and M. Nerlove. 6. Multivariate Stochastic Variance Models. 7. Stochastic Autoregressive...

  6. ANESTHETIC CHALLENGES FACED IN A CHILD WITH TREACHER - COLLINS SYNDROME

    Directory of Open Access Journals (Sweden)

    Sahajananda

    2014-01-01

    Full Text Available Anesthesiologists come across pediatric patients with rare diseases and syndromes scheduled for various operative interventions. Treacher Collins syndrome is a rare genetic disorder characterized by craniofacial deformities , the incidence being 1 in 40 , 000 - 70 , 000 births 1 - 3 . Treacher Collins syndrome (TCS poses serious problem in securing and maintaining airway due to facial deformity. Difficulty in intubation increases as the patient’s age increases. It requires meticulous planning and assessment of the airway prior to each anesthetic technique. Here we describe and discuss successful anesthet ic management of an 8 year old boy posted for cana loplasty of the right ear

  7. Effect of some anesthetics on memory and exploration.

    Science.gov (United States)

    Valzelli, L; Kozak, W; Skorupska, M

    1988-04-01

    A light ether anesthesia in laboratory mice resulted in the complete drop of their memory retrieval to zero for more than three days after the administration. On the contrary, mice that underwent the exploration test after the light ether anesthesia performed as expected, confirming that impairment of memory does not necessarily reflect on exploratory performance. The effect of some anesthetic drugs was then studied on memory retrieval and exploratory behavior. Within this general framework, the anesthetics here studied all worsen memory retrieval, however without inducing clear and long-lasting amnesic effect comparable to that exerted by ether anesthesia. Contrarily, the classically amnesic drug scopolamine, orally administered, enhances memory retrieval and improves exploration.

  8. Pricing Volatility of Stock Returns with Volatile and Persistent Components

    DEFF Research Database (Denmark)

    Zhu, Jie

    2009-01-01

    This paper introduces a two-component volatility model based on first moments of both components to describe the dynamics of speculative return volatility. The two components capture the volatile and the persistent part of volatility, respectively. The model is applied to 10 Asia-Pacific stock...... markets. Their in-mean effects on returns are tested. The empirical results show that the persistent component is much more important for the volatility dynamic process than is the volatile component. However, the volatile component is found to be a significant pricing factor of asset returns for most...... markets. A positive or risk-premium effect exists between the return and the volatile component, yet the persistent component is not significantly priced for the return dynamic process....

  9. Fentanyl, dexmedetomidine, dexamethasone as adjuvant to local anesthetics in caudal analgesia in pediatrics: A comparative study

    Directory of Open Access Journals (Sweden)

    Elham M. El-Feky

    2015-04-01

    Conclusion: Both caudal dexmedetomidine and caudal dexamethasone added to local anesthetics are good alternatives in prolongation of postoperative analgesia compared to caudal local anesthetic alone or added to caudal fentanyl. Also they showed less side effects compared to caudal fentanyl.

  10. Electronic dental anesthesia in a patient with suspected allergy to local anesthetics: report of case.

    Science.gov (United States)

    Malamed, S F; Quinn, C L

    1988-01-01

    A 56-year-old patient with alleged allergy to local anesthetics required restorative dental treatment. Electronic dental anesthesia was used successfully, in lieu of injectable local anesthetics, to manage intraoperative pain associated with the restoration of vital mandibular teeth.

  11. Dynamic Volatility Arbitrage

    DEFF Research Database (Denmark)

    Dorn, Jochen

    concepts, next to nothing is known about position reverting strategies and how, and -even more important- in which context they are applied in practice. In the recent market downturn only one sector generated signicant profits for the leading investment banks: Volatility trading activities, namely on Forex...

  12. Conformation and kinetic characteristics of interactions between local anesthetics and aqueous solutions of hydroxypropylmethylcellulose.

    Science.gov (United States)

    Galenko-Yaroshevskii, A P; Varlashkina, I A; Takhchidi, Kh P; Malyugin, B E; Dukhanin, A S

    2007-05-01

    Conformation and kinetic characteristics of the interactions of local anesthetics lidocaine (xycaine), tetracaine (dicaine), bupivacaine, and new RU-1117 compound with proven anesthetic activity with Visiton (1% hydroxypropylmethylcellulose in phosphate buffer) were studied. It was found that complex formation between the local anesthetics and hydroxypropylmethylcellulose is a time-dependent reversible process. The equilibrium is attained within 2.5-8.0 h and depends on the chemical nature of local anesthetic.

  13. Concentrations of anesthetics across the water-membrane interface; the Meyer-Overton hypothesis revisited

    Science.gov (United States)

    Pohorille, A.; Wilson, M. A.; New, M. H.; Chipot, C.

    1998-01-01

    The free energies of transferring a variety of anesthetic and nonanesthetic compounds across water-oil and water-membrane interfaces were obtained using computer simulations. Anesthetics exhibit greatly enhanced concentrations at these interfaces, compared to nonanesthetics. The substitution of the interfacial solubilites of the anesthetics for their bulk lipid solubilities in the Meyer-Overton relation, was found to give a better correlation, indicating that the potency of an anesthetic is directly proportional to its solubility at the interface.

  14. Assessing the impact on global climate from general anesthetic gases

    DEFF Research Database (Denmark)

    Andersen, Mads P. Sulbæk; Nielsen, Ole John; Wallington, Timothy J.

    2012-01-01

    anthropogenic radiative forcing of climate, as measured relative to the start of the industrial era (approximately 1750). The family of anesthetic gases includes several halogenated organic compounds that are strong greenhouse gases. In this short report, we provide an overview of the state of knowledge...

  15. Differential regional metabolism of glucagon in anesthetized pigs

    DEFF Research Database (Denmark)

    Deacon, Carolyn F; Kelstrup, Mette; Trebbien, Ramona;

    2003-01-01

    Glucagon metabolism under basal (endogenous) conditions and during intravenous glucagon infusion was studied in anesthetized pigs by use of midregion (M), COOH-terminal (C), and NH2-terminal (N)-RIAs. Arteriovenous concentration differences revealed a negative extraction of endogenous glucagon...

  16. Comparison of Two Anesthetic Methods for Intravitreal Ozurdex Injection

    Directory of Open Access Journals (Sweden)

    V. Levent Karabaş

    2015-01-01

    Full Text Available Purpose. To determine whether subconjunctival lidocaine injection maintains additional anesthetic effect during intravitreal Ozurdex injection. Methods. 63 patients who were diagnosed as central or branch retinal vein occlusion and planned to receive Ozurdex injection for macular edema were prospectively included in the study. The patients were randomized into one of the two anesthetic groups. The first group received topical proparacaine drop and lidocaine applied pledget. The second group received subconjunctival lidocaine injection in addition to the anesthetics in group 1. Results. Mean pain score was 1.90±2.39 in group 1 and 1.71 ± 2.09 in group 2 (p=0.746. Mean subconjunctival hemorrhage grade was 1.67±0.17 in group 1 and 0.90±0.14 in group 2 (p=0.001. There was no relationship between the amount of subconjunctival hemorrhage and pain score of the patients. Conclusions. There was no difference in pain scores between the two anesthetic methods. The addition of subconjunctival lidocaine injection offered no advantage in pain relief compared to lidocaine-applied pledgets.

  17. The Anesthetic Effect of Anterior Middle Superior Alveolar Technique (AMSA)

    Science.gov (United States)

    de Souza Tolentino, Lívia; Barbisan Souza, André; Girardi, Ana Alice; Romito, Giuseppe Alexandre; Araújo, Maurício Guimarães

    2015-01-01

    Anesthesia of the soft and hard tissues of the maxilla may require up to 5 injections. Thus, the aim of this study was to evaluate the anesthetic efficacy of the anterior middle superior alveolar (AMSA) and supraperiosteal injection techniques during subgingival scaling and root planing (SRP). Thirty individuals with periodontitis were scheduled for SRP on the buccal aspect of teeth in the anterior maxilla. Before SRP, on a randomly chosen side of the maxilla, the supraperiosteal injection was performed in 1 session, while the AMSA injection was conducted in the contralateral side of the same patient in another session. Immediately after each SRP session, patients rated their pain perception during the procedure with a visual analog scale. No statistically significant differences in mean pain ratings during SRP were found after both anesthetic techniques (P > .05). This preliminary study demonstrated that the AMSA and supraperiosteal injection techniques provided similar anesthetic comfort during SRP. The AMSA injection could be an alternative to anesthetize the buccal aspect of maxilla, without the undesirable effects on facial structures such as the upper lip, nostrils, and lower eyelids. However, further randomized clinical trials with larger samples are necessary to confirm such results. PMID:26650493

  18. Anesthetic keratopathy presenting as bilateral Mooren-like ulcers

    Directory of Open Access Journals (Sweden)

    Khakshoor H

    2012-10-01

    Full Text Available Hamid Khakshoor,1 Majid Moshirfar,2 Rachel G Simpson,3 Hamid Gharaee,1 Amir H Vejdani,1 Steven M Christiansen,2 Jason N Edmonds,2 Nicholas L Behunin21Mashhad University of Medical Sciences, Department of Ophthalmology, Mashad, Iran; 2John A Moran Eye Center, University of Utah, Salt Lake City, UT, 3The University of Arizona College of Medicine, Phoenix, AZ, USAAbstract: This observational case report describes the development of bilateral Mooren-like ulcers in a patient with anesthetic keratopathy. A 42-year-old man with a recent history of minor eye trauma and pain self-treated with tetracaine eye drops presented with complaints of acutely worsening vision and severe pain bilaterally. His visual acuity at presentation was limited to hand motion. Slit-lamp examination revealed bilateral epithelial defects at the center of the cornea, and an area of stromal infiltration and thinning with an undermining leading edge resembling a Mooren's ulcer in both eyes. Corneal haze and hypopyon were visible. Anesthetic use was halted immediately and the patient was started on prednisolone and mycophenolate mofetil (Cellcept®, after which visual acuity gradually improved and pain decreased. Despite improvement of symptoms, residual epithelial defects remained, and the patient was ultimately treated with keratoplasty for recovery of vision. We suggest that anesthetic keratopathy should be included in the differential diagnosis for any patient presenting with ring-shaped stromal infiltrates or nonhealing epithelial defects.Keywords: anesthetic abuse, corneal damage, corneal ulceration

  19. Anesthetic management of a horse with traumatic pneumothorax

    OpenAIRE

    Chesnel, Maud-Aline; Aprea, Francesco; Clutton, R. Eddie

    2012-01-01

    A traumatic pneumothorax and severe hemorrhage were present in a mare with a large thoracic wall defect, lung perforation, and multiple rib fractures. General anesthesia was induced to allow surgical exploration. We describe the anesthetic technique, and discuss the management of the ventilatory, hemodynamic, and metabolic disturbances encountered.

  20. Plant volatiles and the environment

    NARCIS (Netherlands)

    Loreto, F.; Dicke, M.; Schnitzler, J.P.; Turlings, T.C.J.

    2014-01-01

    Volatile organic compounds emitted by plants represent the largest part of biogenic volatile organic compounds (BVOCs) released into our atmosphere. Plant volatiles are formed through many biochemical pathways, constitutively and after stress induction. In recent years, our understanding of the func

  1. The exploitation of volatile oil

    Institute of Scientific and Technical Information of China (English)

    MENG Teng; ZHANG Da; TENG Xiangjin; LINing; HAO Zaibin

    2007-01-01

    Rose is a kind of favorite ornamental plant. This article briefly introduced the cultivation and the use of rose around the world both in ancient time and nowadays. Today, volatile oil becomes the mainstream of the rose industry. People pay attention to the effect of volatile oil; meanwhile, they speed up their research on extracting volatile oil and the ingredients.

  2. Latent Integrated Stochastic Volatility, Realized Volatility, and Implied Volatility: A State Space Approach

    DEFF Research Database (Denmark)

    Bach, Christian; Christensen, Bent Jesper

    We include simultaneously both realized volatility measures based on high-frequency asset returns and implied volatilities backed out of individual traded at the money option prices in a state space approach to the analysis of true underlying volatility. We model integrated volatility as a latent...... fi…rst order Markov process and show that our model is closely related to the CEV and Barndorff-Nielsen & Shephard (2001) models for local volatility. We show that if measurement noise in the observable volatility proxies is not accounted for, then the estimated autoregressive parameter in the latent...... process is downward biased. Implied volatility performs better than any of the alternative realized measures when forecasting future integrated volatility. The results are largely similar across the stock market (S&P 500), bond market (30-year U.S. T-bond), and foreign currency exchange market ($/£ )....

  3. Scaling Foreign Exchange Volatility

    OpenAIRE

    Jonathan Batten; Craig Ellis

    2001-01-01

    When asset returns are normally distributed the risk of an asset over a long return interval may be estimated by scaling the risk from shorter return intervals. While it is well known that asset returns are not normally distributed a key empirical question concerns the effect that scaling the volatility of dependent processes will have on the pricing of related financial assets. This study provides an insight into this issue by investigating the return properties of the most important currenc...

  4. High throughput modular chambers for rapid evaluation of anesthetic sensitivity

    Directory of Open Access Journals (Sweden)

    Eckmann David M

    2006-11-01

    Full Text Available Abstract Background Anesthetic sensitivity is determined by the interaction of multiple genes. Hence, a dissection of genetic contributors would be aided by precise and high throughput behavioral screens. Traditionally, anesthetic phenotyping has addressed only induction of anesthesia, evaluated with dose-response curves, while ignoring potentially important data on emergence from anesthesia. Methods We designed and built a controlled environment apparatus to permit rapid phenotyping of twenty-four mice simultaneously. We used the loss of righting reflex to indicate anesthetic-induced unconsciousness. After fitting the data to a sigmoidal dose-response curve with variable slope, we calculated the MACLORR (EC50, the Hill coefficient, and the 95% confidence intervals bracketing these values. Upon termination of the anesthetic, Emergence timeRR was determined and expressed as the mean ± standard error for each inhaled anesthetic. Results In agreement with several previously published reports we find that the MACLORR of halothane, isoflurane, and sevoflurane in 8–12 week old C57BL/6J mice is 0.79% (95% confidence interval = 0.78 – 0.79%, 0.91% (95% confidence interval = 0.90 – 0.93%, and 1.96% (95% confidence interval = 1.94 – 1.97%, respectively. Hill coefficients for halothane, isoflurane, and sevoflurane are 24.7 (95% confidence interval = 19.8 – 29.7%, 19.2 (95% confidence interval = 14.0 – 24.3%, and 33.1 (95% confidence interval = 27.3 – 38.8%, respectively. After roughly 2.5 MACLORR • hr exposures, mice take 16.00 ± 1.07, 6.19 ± 0.32, and 2.15 ± 0.12 minutes to emerge from halothane, isoflurane, and sevoflurane, respectively. Conclusion This system enabled assessment of inhaled anesthetic responsiveness with a higher precision than that previously reported. It is broadly adaptable for delivering an inhaled therapeutic (or toxin to a population while monitoring its vital signs, motor reflexes, and providing precise control

  5. Is conformation a fundamental descriptor in QSAR? A case for halogenated anesthetics

    Science.gov (United States)

    Guimarães, Maria C; Duarte, Mariene H; Silla, Josué M

    2016-01-01

    Summary An intriguing question in 3D-QSAR lies on which conformation(s) to use when generating molecular descriptors (MD) for correlation with bioactivity values. This is not a simple task because the bioactive conformation in molecule data sets is usually unknown and, therefore, optimized structures in a receptor-free environment are often used to generate the MD´s. In this case, a wrong conformational choice can cause misinterpretation of the QSAR model. The present computational work reports the conformational analysis of the volatile anesthetic isoflurane (2-chloro-2-(difluoromethoxy)-1,1,1-trifluoroethane) in the gas phase and also in polar and nonpolar implicit and explicit solvents to show that stable minima (ruled by intramolecular interactions) do not necessarily coincide with the bioconformation (ruled by enzyme induced fit). Consequently, a QSAR model based on two-dimensional chemical structures was built and exhibited satisfactory modeling/prediction capability and interpretability, then suggesting that these 2D MD´s can be advantageous over some three-dimensional descriptors. PMID:27340468

  6. Vibrational Infrared Lifetime of the Anesthetic nitrous oxide gas in solution

    CERN Document Server

    Chieffo, Logan; Shattuck, Jeffrey; Hong, Mi K; Ziegler, Lawrence; Erramilli, Shyamsunder

    2006-01-01

    The lifetime of the asymmetric fundamental stretching 2218 cm$^{-1}$ vibration of the anesthetic gas nitrous oxide (N$_2$O) dissolved in octanol and olive oil is reported. These solvents are model systems commonly used to assess anesthetic potency. Picosecond time-scale molecular dynamics simulations have suggested that protein dynamics or membrane dynamics play a role in the molecular mechanism of anesthetic action. Ultrafast infrared spectroscopy with 100 fs time resolution is an ideal tool to probe dynamics of anesthetic molecules on such timescales. Pump-probe studies at the peak of the vibrational band yield a lifetime of $55 \\pm 1$ ps in olive oil and $52 \\pm 1 ps$ in octanol. The similarity of lifetimes suggests that energy relaxation of the anesthetic is determined primarily by the hydrophobic nature of the environment, consistent with models of anesthetic action. The results show that nitrous oxide is a good model system for probing anesthetic-solvent interactions using nonlinear infrared spectroscop...

  7. [Anesthetic Management of Three Patients with Chronic Inflammatory Demyelinating Polyradiculoneuropathy].

    Science.gov (United States)

    Maruyama, Naoko; Wakimoto, Mayuko; Inamori, Noriko; Nishimura, Shinya; Mori, Takahiko

    2015-08-01

    Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a chronically progressing or relapsing disease caused by immune-mediated peripheral neuropathy. We report the anesthetic management of three CIDP patients who underwent elective orthopedic surgeries. Owing to the risk of neuraxial anesthetics triggering demyelination, general anesthesia was selected to avoid epidural or spinal anesthesia or other neuraxial blockade. It was also judged prudent to avoid prolonged perioperative immobilization, which might compress vulnerable peripheral nerves. For Patient 1, general anesthesia was induced with propofol, remifentanil, and sevoflurane, and was maintained with sevoflurane and remifentanil. For Patients 2 and 3, general anesthesia was induced and maintained with propofol and remifentanil. For tracheal intubation, under careful monitoring with peripheral nerve stimulators, minimal doses of rocuronium (0.6-0.7 mg x kg(-1)) were administered. When sugammadex was administered to reverse the effect of rocuronium, all patients rapidly regained muscular strength. Postoperative courses were satisfactory without sequelae.

  8. Dissociative anesthetic combination reduces intraocular pressure (IOP in rabbits

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    Ewaldo de Mattos-Junior

    2014-02-01

    Full Text Available The aim of this study was evaluate the effects of three anesthetic combinations, ketamine-midazolam, ketamine-xylazine and tiletamine-zolazepam, on IOP in rabbits. In a experimental, blind, randomized, crossover study, six rabbits were anesthetized with each of 3 treatments in random order. Groups KM (ketamine, 30 mg/kg + midazolam, 1 mg/kg; KX (ketamine, 30 mg/kg + xylazine, 3 mg/kg; and TZ (tiletamine + zolazepam, 20 mg/kg. The drugs were mixed in the same syringe injected intramuscularly (IM into the quadriceps muscle. IOP was measured before drug administration (baseline and at 5-minute intervals for 30 minutes. The data were analyzed by a 2-way repeated measures ANOVA followed by Bonferroni test. All groups had significant decreases in IOP compared to baseline (p 0.05. Administration of either ketamine-midazolam, ketamine-xylazine, or tiletamine-zolazepam similarly decrease IOP in rabbits within 30 minutes of injection.

  9. Efficacy of benzocaine as an anesthetic for salmonid fishes

    Science.gov (United States)

    Gilderhus, P.A.

    1989-01-01

    Benzocaine was tested in the laboratory to determine the effective concentrations for anesthetizing juvenile chinook salmon Oncorhynchus tshawytscha an rainbow trout O. mykiss (formerly Salmo gairdneri ). Tests were conducted at three water temperatures, in waters ranging from very soft to very hard, and with groups of rainbow trout from 5 to 47 cm long and chinook salmon 20 cm long. Effective concentrations were defined as those that rendered the fish fully handleable in 3 min or less, allowed recovery of most fish within 10 min, and caused no mortality after 15-min exposures. Concentrations of 25-45 mg/L anesthetized both species over the entire range of conditions tested. Although efficacy was essentially unrelated to species or water quality, it was related to water temperature and size of fish; the concentrations of benzocaine required were highest at the lowest water temperature and for the largest fish.

  10. Refractometry for quality control of anesthetic drug mixtures.

    Science.gov (United States)

    Stabenow, Jennifer M; Maske, Mindy L; Vogler, George A

    2006-07-01

    Injectable anesthetic drugs used in rodents are often mixed and further diluted to increase the convenience and accuracy of dosing. We evaluated clinical refractometry as a simple and rapid method of quality control and mixing error detection of rodent anesthetic or analgesic mixtures. Dilutions of ketamine, xylazine, acepromazine, and buprenorphine were prepared with reagent-grade water to produce at least 4 concentration levels. The refraction of each concentration then was measured with a clinical refractometer and plotted against the percentage of stock concentration. The resulting graphs were linear and could be used to determine the concentration of single-drug dilutions or to predict the refraction of drug mixtures. We conclude that refractometry can be used to assess the concentration of dilutions of single drugs and can verify the mixing accuracy of drug combinations when the components of the mixture are known and fall within the detection range of the instrument.

  11. Antidepressants and local anesthetics: drug interactions of interest to dentistry

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    Lea Rosa Chioca

    2010-10-01

    Full Text Available Introduction: Since there is a vast variety of pharmacological treatments for mental conditions, it has been increasingly more common that patients seeking dentistry treatment are continually using psychoactive drugs as antidepressants. The number of people taking antidepressants is increasing; consequently, dentists should update their knowledge on the interaction between this drug class and those used in dental daily practice, such as local anesthetics and vasoconstrictors. Objective: To conduct a literature review on this subject. Literature review and conclusion: Literature data suggest that sympathomimetic vasoconstrictors (epinephrine, norepinephrine, and phenylephrine associated with local anesthetics may potentiate the side effects of antidepressants, particularly tricyclics and MAO inhibitors, on the cardiovascular system. There are few clinical trials and preclinical studies on this subject, and most of them were carried out between the 60s and 80s. Current studies are needed, since many new antidepressant drugs with different mechanisms of action are currently marketed and being used.

  12. Mechanics and Morphology of Silk Drawn from Anesthetized Spiders

    Science.gov (United States)

    Madsen, B.; Vollrath, F.

    CO2 and N2 anesthetized Nephila spiders produced dragline silk with mechanical properties that differed from control silk as a function of time under anesthesia. Silk from CO2 spiders had a significantly lower breaking strain and breaking energy, significantly higher initial modulus, and marginally lower breaking stress. At the onset of anesthesia the silk diameter became highly variable. During deep anesthesia silk either became thinner or retained cross-section but fibrillated.

  13. ANESTHETIC CONSIDERATION S IN CHRONIC OBSTRUCTIVE PULMON ARY DISEASE

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    Awati

    2015-03-01

    Full Text Available Chronic obstructive pulmonary disease (COPD is a spectrum of diseases that includes emphysema, chronic bronchitis, and small airway disease. It i s characterized by progressive increased resistance to breathing. Patients with marked obstructive pulmonary disease are at increased risk for both intraoperative and Postoperative pulmonary complications. These patients require thorough preoperative prepa ration, meticulous intraoperative management & postoperative care. This article describes anesthetic considerations in a patient with COPD.

  14. Assessment of patient satisfaction with the preoperative anesthetic evaluation

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    Gebremedhn EG

    2014-09-01

    Full Text Available Endale Gebreegziabher Gebremedhn, Vidhya Nagaratnam Department of Anesthesia, School of Medicine, Gondar College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia Background: The evaluation of patient satisfaction is a core aspect of the continuous quality improvement in anesthesia service that can be affected by the preoperative anesthetist visit. This visit enables the anesthetist to know about the patient's general health status and the nature of surgery, to choose the type of anesthesia, and to discuss perioperative complications and their management with the patient. Patients have sometimes complained about the information given during the preoperative anesthetic evaluation in the University of Gondar teaching and referral hospital. The aim of this study was to determine the level of patient satisfaction with the preoperative anesthetist visit. Methods: A cross-sectional study was conducted from February 15 to April 15, 2013. All consecutive elective patients who were operated upon under anesthesia during the study period were interviewed 24 hours after operation. A pretested questionnaire and checklists, which were developed based on the hospital's anesthetic evaluation sheet, were used for data collection. Results: A total of 116 elective patients were operated upon under anesthesia during the study period. Of these, 102 patients were included in our study, with a response rate of 87.9%. Anesthetists introduced themselves to ~24% patients; provided information about anesthesia to ~32%, postoperative complications to ~21%, postoperative analgesia to ~18, and postoperative nausea and vomiting to ~21%; and spent adequate time with ~74%. Patients' questions were answered by the anesthetist in ~65% of cases, and ~65% of patients had reduced anxiety after the anesthetist visit. The patients' overall satisfaction with the preoperative anesthetist visit was ~65%. Conclusion and recommendation: Patient satisfaction with the

  15. Anesthetic Management in a Gravida with Type IV Osteogenesis Imperfecta

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    Elizabeth Vue

    2016-01-01

    Full Text Available Osteogenesis imperfecta (OI is an inherited disorder of the connective tissues caused by abnormalities in collagen formation. OI may present many challenges to the anesthesiologist. A literature review reveals a wide range of implications, from basic positioning to management of the difficult airway. We present the anesthetic management of a 25-year-old gravid woman with OI, fetal demise, and possible uterine rupture, admitted for an exploratory laparotomy.

  16. Intraperitoneal Local Anesthetic in Pediatric Surgery: A Systematic Review.

    Science.gov (United States)

    Hamill, James K; Rahiri, Jamie-Lee; Liley, Andrew; Hill, Andrew G

    2016-12-01

    Introduction Systematic reviews report intraperitoneal local anesthetic (IPLA) effective in adults but until now no review has addressed IPLA in children. The objective of this review was to answer the question, does IPLA compared with control reduce pain after pediatric abdominal surgery. Materials and Methods Data sources: MEDLINE, EMBASE, Cochrane databases, trials registries, ProQuest, Web of Science, Google Scholar, and Open Gray.

  17. Neuropathological sequelae of developmental exposure to antiepileptic and anesthetic drugs

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    Chrysanthy eIkonomidou

    2012-08-01

    Full Text Available Glutamate (Glu and aminobutyric acid (GABA are major neurotransmitters in the mammalian brain which regulate brain development at molecular, cellular and systems level. Sedative, anesthetic and antiepileptic drugs interact with glutamate and GABA receptors to produce their desired effects. The question is posed whether such interference with glutamatergic and GABAergic neurotransmission may exert undesired, and perhaps even detrimental effects on human brain development. Preclinical research in rodents and non-human primates has provided extensive evidence that sedative, anesthetic and antiepileptic drugs can trigger suicide of neurons and oligodendroglia, suppress neurogenesis, and inhibit normal synapse development and sculpting. Behavioral correlates in rodents and non-human primates consist of long-lasting cognitive impairment. Retrospective clinical studies in humans exposed to anesthetics or antiepileptic drugs in utero, during infancy or early childhood have delivered conflicting but concerning results in terms of a correlation between drug exposure and impaired neurodevelopmental outcomes. Prospective studies are currently ongoing. This review provides a short overview of the current state of knowledge on this topic.

  18. Effect of anesthetics on bending elasticity of lipid membranes

    Science.gov (United States)

    Yi, Zheng; Michihiro, Nagao; Bossev, Dobrin

    2008-03-01

    Change in physical and chemical properties of bio-membranes is of great interest for understanding the mechanism of anesthetic action on membranes. Hypothetically the anesthetic alters the lipid membrane structure (promoting pore formation across membranes or at least switching transmembrane channels) and therefore the biophysical properties of the membrane. We have used neutron spin echo (NSE) spectroscopy to study the effect of anesthetic molecule, lidocaine, on the bending elasticity (BE) of lipid membranes. BE of lipid bilayers made of (1,2-Dimyristoyl-sn-Glycero-3-Phosphocholine) DMPC and 1,2-Dipalmitoyl-sn-Glycero-3-Phosphocholine (DPPC) have been measured at different temperatures and different in the fluid (Lα) phase. Using Zilman-Granek theory the BE were obtained from the decay of the NSE intermediate scattering function. We have found that in the presence of lidocaine the BE of DMPC and DPPC bilayers increases. The results were correlated with those from differential scanning calorimetry. Increase in the lidocaine concentration leads to decrease in the liquid/crystalline transition temperature.

  19. Near-Infrared Spectroscopy for the Evaluation of Anesthetic Depth

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    Gabriela Hernandez-Meza

    2015-01-01

    Full Text Available The standard-of-care guidelines published by the American Society of Anesthesiologists (ASA recommend monitoring of pulse oximetry, blood pressure, heart rate, and end tidal CO2 during the use of anesthesia and sedation. This information can help to identify adverse events that may occur during procedures. However, these parameters are not specific to the effects of anesthetics or sedatives, and therefore they offer little, to no, real time information regarding the effects of those agents and do not give the clinician the lead-time necessary to prevent patient “awareness.” Since no “gold-standard” method is available to continuously, reliably, and effectively monitor the effects of sedatives and anesthetics, such a method is greatly needed. Investigation of the use of functional near-infrared spectroscopy (fNIRS as a method for anesthesia or sedation monitoring and for the assessment of the effects of various anesthetic drugs on cerebral oxygenation has started to be conducted. The objective of this paper is to provide a thorough review of the currently available published scientific studies regarding the use of fNIRS in the fields of anesthesia and sedation monitoring, comment on their findings, and discuss the future work required for the translation of this technology to the clinical setting.

  20. The bonding of anesthetics and antibiotics on the carboxymethylcellulose

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    Rodić-Grabovac Branka B.

    2007-01-01

    Full Text Available The preparation of biologically active material is one of the most interesting trends in the chemical modification of cellulose. The possibility of obtaining biologically active cellulosic material by sorption of procaine hydrochloride and gentamicin sulphate on CMC was investigated in this paper. The sorption of therapeutics on CMC samples with different degree of substitution was carried out in water solutions of anesthetic and antibiotic, while the desorption was done in 0.95% NaCl solution. The amount of bonded and released therapeutics was determined by UV spe-ctrophotometry. It was found that degree of substitution of car-boxymethylcellulose and concentration of chemotherapeutic water solution have significant influence on the amount of bonded anesthetic and antibiotic. The maximum amount of bonded chemotherapeutic was 72.15 mg of procaine hydrochloride and 165.49 mg of gentamicin sulphate per gram CMC. In both cases the amounts of bonded chemotherape-utics correspond to the concentration of local anesthetic and antibiotic preparation that are used in therapeutic purposes.

  1. Interactions of some local anesthetics and alcohols with membranes.

    Science.gov (United States)

    Frangopol, P T.; Mihăilescu, D

    2001-09-01

    A review of the results obtained by our group in the last decade regarding the interactions of procaine, lidocaine, dibucaine and tetracaine with membranes is presented in the context of the literature data. The action upon membranes, in first approximation monomolecular film of stearic acid spread at the air/water interface used as a membrane model, the modification of biomembrane structure and function using diffraction methods, lipid phase transition, fluidity of lipids and proteins, membrane expansion and platelet aggregation were studied. The thermodynamic knowledge of membrane-alcohol interactions improved by using highly sensitive calorimetric techniques are briefly reported. One of the main conclusions is that the physical state of a monolayer model membrane was the result of competitive interactions between film-film and film-substrate interactions. It was taken into account that local anesthetics, such as lidocaine, carbisocaine, mesocaine, showed changes in the bilayer structure, reflected in macroscopic mechanical properties. This restructuring of the lipid bilayer has a significant influence on the operation of functional subunits, e.g. ionic channels formed by gramicidin. The results support the concept of non-specific interactions of local anesthetics with lipid bilayers. The theoretical modeling of the interactions of local anesthetics is closely compared with experimental data. Our new theory of relaxation for these interactions is using a non-archimedean formalism based on a process resulting from superpositions of different component processes which take place at different scales of time.

  2. Anesthetic Efficacy in Irreversible Pulpitis: A Randomized Clinical Trial.

    Science.gov (United States)

    Allegretti, Carlos E; Sampaio, Roberta M; Horliana, Anna C R T; Armonia, Paschoal L; Rocha, Rodney G; Tortamano, Isabel Peixoto

    2016-01-01

    Inferior alveolar nerve block has a high failure rate in the treatment of mandibular posterior teeth with irreversible pulpitis. The aim of this study was to compare the anesthetic efficacy of 4% articaine, 2% lidocaine and 2% mepivacaine, all in combination with 1:100,000 epinephrine, in patients with irreversible pulpitis of permanent mandibular molars during a pulpectomy procedure. Sixty-six volunteers from the Emergency Center of the School of Dentistry, University of São Paulo, randomly received 3.6 mL of local anesthetic as a conventional inferior alveolar nerve block (IANB). The subjective signal of lip numbness, pulpal anesthesia and absence of pain during the pulpectomy procedure were evaluated respectively, by questioning the patient, stimulation using an electric pulp tester and a verbal analogue scale. All patients reported the subjective signal of lip numbness. Regarding pulpal anesthesia success as measured with the pulp tester, the success rate was respectively 68.2% for mepivacaine, 63.6% for articaine and 63.6% for lidocaine. Regarding patients who reported no pain or mild pain during the pulpectomy, the success rate was, respectively 72.7% for mepivacaine, 63.6% for articaine and 54.5% for lidocaine. These differences were not statistically significant. Neither of the solutions resulted in 100% anesthetic success in patients with irreversible pulpitis of mandibular molars.

  3. Post-anesthetic cortical blindness in cats: twenty cases.

    Science.gov (United States)

    Stiles, J; Weil, A B; Packer, R A; Lantz, G C

    2012-08-01

    The medical records of 20 cats with post-anesthetic cortical blindness were reviewed. Information collected included signalment and health status, reason for anesthesia, anesthetic protocols and adverse events, post-anesthetic visual and neurological abnormalities, clinical outcome, and risk factors. The vascular anatomy of the cat brain was reviewed by cadaver dissections. Thirteen cats were anaesthetised for dentistry, four for endoscopy, two for neutering procedures and one for urethral obstruction. A mouth gag was used in 16/20 cats. Three cats had had cardiac arrest, whereas in the remaining 17 cases, no specific cause of blindness was identified. Seventeen cats (85%) had neurological deficits in addition to blindness. Fourteen of 20 cats (70%) had documented recovery of vision, whereas four (20%) remained blind. Two cats (10%) were lost to follow up while still blind. Ten of 17 cats (59%) with neurological deficits had full recovery from neurological disease, two (12%) had mild persistent deficits and one (6%) was euthanased as it failed to recover. Four cats (23%) without documented resolution of neurological signs were lost to follow up. Mouth gags were identified as a potential risk factor for cerebral ischemia and blindness in cats.

  4. Option Pricing using Realized Volatility

    DEFF Research Database (Denmark)

    Stentoft, Lars Peter

    In the present paper we suggest to model Realized Volatility, an estimate of daily volatility based on high frequency data, as an Inverse Gaussian distributed variable with time varying mean, and we examine the joint properties of Realized Volatility and asset returns. We derive the appropriate...... benchmark model estimated on return data alone. Hence the paper provides evidence on the value of using high frequency data for option pricing purposes....

  5. Anesthetic neuroprotection: antecedents and an appraisal of preclinical and clinical data quality.

    Science.gov (United States)

    Ishida, Kazuyoshi; Berger, Miles; Nadler, Jacob; Warner, David S

    2014-01-01

    Anesthetics have been studied for nearly fifty years as potential neuroprotective compounds in both perioperative and resuscitation medicine. Although anesthetics present pharmacologic properties consistent with preservation of brain viability in the context of an ischemic insult, no anesthetic has been proven efficacious for neuroprotection in humans. After such effort, it could be concluded that anesthetics are simply not neuroprotective in humans. Moreover, pharmacologic neuroprotection with non-anesthetic drugs has also repeatedly failed to be demonstrated in human acute brain injury. Recent focus has been on rectification of promising preclinical neuroprotection data and subsequent failed clinical trials. This has led to consensus guidelines for the process of transferring purported therapeutics from bench to bedside. In this review we first examined the history of anesthetic neuroprotection research. Then, a systematic review was performed to identify major clinical trials of anesthetic neuroprotection. Both the preclinical neuroprotection portfolio cited to justify a clinical trial and the design and conduct of that clinical trial were evaluated using modern standards that include the Stroke Therapy Academic Industry Roundtable (STAIR) and Consolidated Standards of Reporting Trials (CONSORT) guidelines. In publications intended to define anesthetic neuroprotection, we found overall poor quality of both preclinical efficacy analysis portfolios and clinical trial designs and conduct. Hence, using current translational research standards, it was not possible to conclude from existing data whether anesthetics ameliorate perioperative ischemic brain injury. Incorporation of advances in translational neuroprotection research conduct may provide a basis for more definitive and potentially successful clinical trials of anesthetics as neuroprotectants.

  6. Vasoconstriction Potency Induced by Aminoamide Local Anesthetics Correlates with Lipid Solubility

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    Hui-Jin Sung

    2012-01-01

    Full Text Available Aminoamide local anesthetics induce vasoconstriction in vivo and in vitro. The goals of this in vitro study were to investigate the potency of local anesthetic-induced vasoconstriction and to identify the physicochemical property (octanol/buffer partition coefficient, pKa, molecular weight, or potency of local anesthetics that determines their potency in inducing isolated rat aortic ring contraction. Cumulative concentration-response curves to local anesthetics (levobupivacaine, ropivacaine, lidocaine, and mepivacaine were obtained from isolated rat aorta. Regression analyses were performed to determine the relationship between the reported physicochemical properties of local anesthetics and the local anesthetic concentration that produced 50% (ED50 of the local anesthetic-induced maximum vasoconstriction. We determined the order of potency (ED50 of vasoconstriction among local anesthetics to be levobupivacaine > ropivacaine > lidocaine > mepivacaine. The relative importance of the independent variables that affect the vasoconstriction potency is octanol/buffer partition coefficient > potency > pKa > molecular weight. The ED50 in endothelium-denuded aorta negatively correlated with the octanol/buffer partition coefficient of local anesthetics (r2=0.9563; P<0.001. The potency of the vasoconstriction in the endothelium-denuded aorta induced by local anesthetics is determined primarily by lipid solubility and, in part, by other physicochemical properties including potency and pKa.

  7. Molecular plant volatile communication.

    Science.gov (United States)

    Holopainen, Jarmo K; Blande, James D

    2012-01-01

    Plants produce a wide array of volatile organic compounds (VOCs) which have multiple functions as internal plant hormones (e.g., ethylene, methyl jasmonate and methyl salicylate), in communication with conspecific and heterospecific plants and in communication with organisms of second (herbivores and pollinators) and third (enemies of herbivores) trophic levels. Species specific VOCs normally repel polyphagous herbivores and those specialised on other plant species, but may attract specialist herbivores and their natural enemies, which use VOCs as host location cues. Attraction of predators and parasitoids by VOCs is considered an evolved indirect defence, whereby plants are able to indirectly reduce biotic stress caused by damaging herbivores. In this chapter we review these interactions where VOCs are known to play a crucial role. We then discuss the importance of volatile communication in self and nonself detection. VOCs are suggested to appear in soil ecosystems where distinction of own roots from neighbours roots is essential to optimise root growth, but limited evidence of above-ground plant self-recognition is available.

  8. Volatile signals during pregnancy.

    Science.gov (United States)

    Vaglio, Stefano

    2010-01-01

    Scents play a key role in mediating reproductive interactions in many vertebrates including mammals. Nowadays, several studies indicate that humans seem to use remarkably olfactory communication and are even able to produce and perceive pheromones. Furthermore, over the past several years, it became increasingly clear that pheromone-like chemical signals probably play a role in offspring identification and mother recognition. Recently developed technical procedures (solid-phase microextraction and dynamic headspace extraction) now allow investigators to characterize volatile compounds with high reliability. We analyzed the volatile compounds in sweat patch samples collected from the para-axillary and nipple-areola regions of women during pregnancy and after childbirth. We hypothesized that, at the time of birth and during the first weeks of life, the distinctive olfactory pattern of the para-axillary area is probably useful to newborn babies for recognizing and distinguishing their own mother, whereas the characteristic pattern of the nipple-areola region is probably useful as a guide to nourishment.

  9. Q型烟粉虱化学感受蛋白CSP1与植物挥发物的结合特征%Binding Characterization of Chemosensory Protein CSP1 in the Bemisia tabaci Biotype Q with Plant Volatiles

    Institute of Scientific and Technical Information of China (English)

    吴帆; 张晓曼; 赵磊; 崔旭红; 李红亮; 罗晨

    2015-01-01

    α-蒎烯(KD值分别为26.47、39.43、54.01和83.46µmol∙L-1),且3-蒈烯具有较强的竞争结合能力,能在200µmol∙L-1时将1-NPN报告子相对荧光值竞争至约40%。【结论】Q型烟粉虱CSP1蛋白能与测试的多种寄主植物挥发物产生较为广谱的结合能力,尤其与对烟粉虱有趋避性的挥发物的结合更强,表明CSP1很有可能参与Q型烟粉虱对非寄主植物的趋避行为,这对揭示其入侵寄主选择行为生理机制具有重要意义。%[Objective]The objective of this study is to clone the ORF (open reading frame) of chemosensory protein 1 (CSP1) from Bemisia tabaci biotype Q, and characterize the binding profiles of CSP1 with some candidate plants volatiles.[Method] By means of full-length ORF primer, reverse transcription-polymerase chain reaction (RT-PCR) was used to amplify the full-length ORF BtCSP1, which was then cloned into the pET-30a (+)/BL21 (DE3) prokaryotic expression vector after double enzyme digestion. The recombinant BtCSP1 protein was expressed and purified by the method of Ni2+-agroase affinity chromatograph. The protein concentration was measured with Bradford method. The competitive fluorescence assay was used to analyze the binding properties of BtCSP1 with general plant volatiles with different chemical structures. As a suitable fluorescence reporter in studies of insect GOBPs’ function in vivo, N-phenyl-1-naphthylamine (1-NPN) was used to titrate the BtCSP1 solution until the fluorescence emission peak at maximum wavelength of BtCSP1 completely quenched. Then all plant volatiles were added into BtCSP1-1-NPN complex, respectively. The dissociation constants K D data represented the affinity of BtCSP1 with ligands were calculated by the Scatchard equation. [Result] BtCSP1 protein was successfully expressed after induction of 1 mmol·L-1 of IPTG, then purified by Ni2+affinity column with gradient imidazole as washing solutions, finally dialyzed sufficiently using PBS buffer. The working

  10. Consistent ranking of volatility models

    DEFF Research Database (Denmark)

    Hansen, Peter Reinhard; Lunde, Asger

    2006-01-01

    We show that the empirical ranking of volatility models can be inconsistent for the true ranking if the evaluation is based on a proxy for the population measure of volatility. For example, the substitution of a squared return for the conditional variance in the evaluation of ARCH-type models can...

  11. Political institutions and economic volatility

    NARCIS (Netherlands)

    Klomp, Jeroen; de Haan, Jakob

    2009-01-01

    We examine the effect of political 'institutions' on economic growth volatility, using data from more than 100 countries over the period 1960 to 2005, taking into account various control variables as suggested in previous studies. Our indicator of volatility is the relative standard deviation of the

  12. Anesthetic management of a case with hereditary spherocytosis for splenectomy and open cholecystectomy

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    Sonal S Khatavkar

    2016-01-01

    Full Text Available Hereditary spherocytosis (HS is a familial hemolytic disorder with marked heterogeneity of clinical features ranging from asymptomatic condition to a fulminant hemolytic anemia. HS is characterized by the strong family history of anemia, jaundice, splenomegaly and cholelithiasis. Anesthetic Management of HS with liver dysfunction is very challenging since most of the anesthetic drugs are metabolized by the liver. Hereby, we report anesthetic management in a case of HS with splenomegaly and gall stones for elective splenectomy and cholecystectomy.

  13. Governmentally amplified output volatility

    Science.gov (United States)

    Funashima, Yoshito

    2016-11-01

    Predominant government behavior is decomposed by frequency into several periodic components: updating cycles of infrastructure, Kuznets cycles, fiscal policy over business cycles, and election cycles. Little is known, however, about the theoretical impact of such cyclical behavior in public finance on output fluctuations. Based on a standard neoclassical growth model, this study intends to examine the frequency at which public investment cycles are relevant to output fluctuations. We find an inverted U-shaped relationship between output volatility and length of cycle in public investment. This implies that periodic behavior in public investment at a certain frequency range can cause aggravated output resonance. Moreover, we present an empirical analysis to test the theoretical implication, using the U.S. data in the period from 1968 to 2015. The empirical results suggest that such resonance phenomena change from low to high frequency.

  14. Reduced Heart Rate Volatility

    Science.gov (United States)

    Grogan, Eric L.; Morris, John A.; Norris, Patrick R.; France, Daniel J.; Ozdas, Asli; Stiles, Renée A.; Harris, Paul A.; Dawant, Benoit M.; Speroff, Theodore

    2004-01-01

    Objective: To determine if using dense data capture to measure heart rate volatility (standard deviation) measured in 5-minute intervals predicts death. Background: Fundamental approaches to assessing vital signs in the critically ill have changed little since the early 1900s. Our prior work in this area has demonstrated the utility of densely sampled data and, in particular, heart rate volatility over the entire patient stay, for predicting death and prolonged ventilation. Methods: Approximately 120 million heart rate data points were prospectively collected and archived from 1316 trauma ICU patients over 30 months. Data were sampled every 1 to 4 seconds, stored in a relational database, linked to outcome data, and de-identified. HR standard deviation was continuously computed over 5-minute intervals (CVRD, cardiac volatility–related dysfunction). Logistic regression models incorporating age and injury severity score were developed on a test set of patients (N = 923), and prospectively analyzed in a distinct validation set (N = 393) for the first 24 hours of ICU data. Results: Distribution of CVRD varied by survival in the test set. Prospective evaluation of the model in the validation set gave an area in the receiver operating curve of 0.81 with a sensitivity and specificity of 70.1 and 80.0, respectively. CVRD predict death as early as 24 hours in the validation set. Conclusions: CVRD identifies a subgroup of patients with a high probability of dying. Death is predicted within first 24 hours of stay. We hypothesize CVRD is a surrogate for autonomic nervous system dysfunction. PMID:15319726

  15. COMPARISON OF COMMON CLINICALLY USED LOCAL ANESTHETICS ON ANIMAL MODELS

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    Anthireddy Srinivas

    2012-08-01

    Full Text Available The animal models used in this study were Plexus anesthesia in frogs, Infiltration anesthesia in guinea pigs, Surface anesthesia in rabbits. The drugs were diluted with normal saline. Lignocaine2%: xylocaine hydrochloride injection IP, Bupivacaine 0.5%: Bupivacaine hydrochloride injections IP were prepared. Plexus anesthesia: Frog was pithed and spinal cord was destroyed up to the 3 vertebra. The abdominal pouch was filled with local anesthetic solution. Reflex activity was tested by immersing both feet of the frog every two minutes for not longer than 10 seconds into N/10 Hydrochloric acid. The time was noted. Surface anesthesia: Albino rabbits of either sex weighing 2.5 – 3.0kg ware selected. The conjunctival sac of one eye was held open, thus formed a pouch. 0.5ml of solution of the anesthetic was applied into the conjunctival sac for 30 sec. Infiltration anesthesia: Preparation of guinea pig: Guinea pigs (either sex weighing 250-300grams were used. Lignocaine produced rapid onset of plexus anesthesia in Frogs in comparison to the bupivacaine at concentration of 0.1% & 0.2% which is statistically significant. Bupivacaine is more potent than the lignocaine as a surface anesthetic agent in the Rabbit, where as lignocaine could produce surface anesthesia at concentration of 0.5% or 0.1% or both. Both bupivacaine and lignocaine produced infiltration anesthesia on intradermal injection in guinea pigs but the duration of infiltration anesthesia produced by bupivacaine is more prolonged which is statistically significant in comparison to the lignocaine at all the three concentrations tested i.e. 0.05%, 0.1% & 0.2%.

  16. Clinical features of pheochromocytoma and perioperative anesthetic management

    Institute of Scientific and Technical Information of China (English)

    罗爱伦; 郭向阳; 易杰; 任洪智; 黄宇光; 叶铁虎

    2003-01-01

    Objective To investigate clinical features of pheochromocytoma and summarize experiences of anesthetic management during the perioperative period. Methods Two hundred and fifty eight patients who were diagnosed with pheochromocytoma in our hospital were reviewed retrospectively for clinical features. According to different preoperative pharmalogical preparations, perioperative mortalities were analyzed in three periods (Period 1: January 1955-December 1975; Period 2: January 1976-December 1994; Period 3: January 1995-July 2001). In Period 3, hemodynamic changes in the patients undergoing different anesthetic methods were analyzed. Results About 5.8% (15/258) of pheochromocytoma was an integral part of multiple endocrine neoplasia (MEN) type Ⅱ or mixed type. Sixty percent (149/249) of the patients who had undergone surgery possessed evidence of catecholamine cardiac toxicity preoperatively. Impaired glucose tolerance was found in 59% (147/249) of the patients before surgery. Perioperative mortality was significantly decreased from 8% (5/60) in Period 1 to 1.2% (1/75) in Period 2 (P<0.01). No perioperative deaths occurred in Period 3. The volume infused during the operation was significantly higher both in the epidural anesthesia group (3474 ml±624 ml, P<0.01) and in the epidural plus general anesthesia group (3654 ml±475 ml, P<0.01) than in the general anesthesia group (2534 ml±512 ml). There were favorable hemodynamic characteristics in patients before removal of the tumor in the epidural anesthesia group and in the epidural plus general anesthesia group, as compared with the general anesthesia group. Conclusions A positive surgical outcome of the excision of pheochromocytoma depends on multiple factors, including careful assessment of potential vital organ damage before surgery and restoration of blood volume by establishing α-blockade preoperatively, meticulous anesthetic management of patients during surgery, and appropriate circulatory support after

  17. Loss of anatomical landmarks with eutectic mixture of local anesthetic cream for neonatal male circumcision.

    Science.gov (United States)

    Plank, Rebeca M; Kubiak, David W; Abdullahi, Rasak Bamidele; Ndubuka, Nnamdi; Nkgau, Maggie M; Dapaah-Siakwan, Fredrick; Powis, Kathleen M; Lockman, Shahin

    2013-02-01

    We report two cases of newborns who developed marked local edema after application of a eutectic mixture of local anesthetic (EMLA) topical anesthetic cream for neonatal male circumcision (NMC). Although local edema and erythema are known potential side effects of EMLA cream, a common anesthetic used for NMC, the loss of landmarks precluding safe NMC has not previously been reported, and is described here. Although we cannot recommend an alternate local anesthetic for neonates with this reaction to EMLA, based on a review of the published data we think that serious systemic adverse events related to EMLA are extremely rare.

  18. Update on administration of anesthetics and psychoactive drugs for pain management in China.

    Science.gov (United States)

    Gu, Weiping

    2015-06-01

    Anesthetics and psychoactive drugs could relieve diseases, if used properly. However, they can cause dependency, and their misuse or abuse could adversely affect people's health and social stability. For a long time, the Chinese government has been reinforcing the regulation on anesthetics and psychoactive drugs to ensure their legal and proper usage, and to prevent abuse. The state council issued 'the regulations on the administration of anesthetic drugs and psychotropic drugs' in 2005, based on which a legal system was established for administration of anesthetics and psychoactive drugs with the objectives of ensuring their legitimate medical utilization, and preventing illegal abuse.

  19. Cimetidine as pre-anesthetic agent for cesarean section

    DEFF Research Database (Denmark)

    Qvist, N; Storm, K; Holmskov, A

    1985-01-01

    In a prospective randomized study of 39 consecutive cesarean sections, 20 patients received cimetidine 400 mg intramuscularly as a pre-anesthetic, an 19 control patients were given NaCl. No perinatal effects on the infants were observed by cardiotocography before delivery, and K, Na, pH, PCO2, HCO......-3 and glucose values in capillary blood were nearly identical in the two groups 2 hours after birth, the difference being non-significant (p greater than 0.05). No respiratory effects or arrhythmias were observed. In another study comprising 8 elective cesarean sections in patients...

  20. Anesthetic management of a pediatric patient with neuroleptic malignant syndrome.

    Science.gov (United States)

    Bhalla, Tarun; Maxey, Douglas; Sawardekar, Amod; Tobias, Joseph D

    2012-04-01

    Neuroleptic malignant syndrome (NMS) is a rare disorder which is clinically similar to malignant hyperthermia (MH). It is characterized by hyperthermia, autonomic instability, muscle rigidity, coma, rhabdomyolysis, and acidosis. Without immediate and appropriate therapy, mortality may result. NMS is associated with administration of antipsychotic medications, anti-emetic medications, and changes in the dosage of anti-parkinsonian drugs. As several similarities exist between NMS and MH, differentiating between them can be a challenge for the clinician. We report anesthetic care during magnetic resonance imaging of the brain of a 14-year-old female with bipolar and schizoaffective disorders and the recent onset of NMS.

  1. Anesthetic management of a child with Hunter′s syndrome

    Directory of Open Access Journals (Sweden)

    Jasmeet Kaur

    2012-01-01

    Full Text Available Hunter′s syndrome is a member of a group of recessively inherited metabolic disorders termed mucopolysaccharidoses, caused by deficiency of lysosomal enzymes required for degradation of mucopolysaccharides or glycosaminoglycans, leading to accumulation of partially degraded glycosaminoglycans in various tissues. This leads to various anatomical abnormalities and systemic involvement, posing a challenge to an anesthetist. We present the anesthetic management of a 4-year old child with Hunter′s disease with anticipated difficult airway, who presented for adenotonsillectomy and repair of umbilical and inguinal hernia.

  2. Central bronchial carcinoid: Management of a case and anesthetic perspectives

    Science.gov (United States)

    Goswami, D; Kashyap, L; Batra, RK; Bhagat, C

    2016-01-01

    Obstructing lesions of the central airways present with a variety of symptoms and are often associated with pneumonia or asthma-like states. Anesthesia to these patients often presents challenges right from the preoperative stabilization of underlying lung condition, mask ventilation in the supine position to maintaining oxygenation and ventilation in the intraoperative and postoperative period. We present here a case of a young woman with a central bronchial tumor with significant airway obstruction with potential for major bleeding and subsequent anesthetic management without lung sacrificing measures and cardiopulmonary bypass assistance. PMID:26955320

  3. Central bronchial carcinoid: Management of a case and anesthetic perspectives

    Directory of Open Access Journals (Sweden)

    D Goswami

    2016-01-01

    Full Text Available Obstructing lesions of the central airways present with a variety of symptoms and are often associated with pneumonia or asthma-like states. Anesthesia to these patients often presents challenges right from the preoperative stabilization of underlying lung condition, mask ventilation in the supine position to maintaining oxygenation and ventilation in the intraoperative and postoperative period. We present here a case of a young woman with a central bronchial tumor with significant airway obstruction with potential for major bleeding and subsequent anesthetic management without lung sacrificing measures and cardiopulmonary bypass assistance.

  4. The anesthetic management in the patient with Kabuki makeup syndrome

    Directory of Open Access Journals (Sweden)

    İsmail Aydın Erden

    2013-03-01

    Full Text Available Kabuki makeup syndrome is characterized by mentalretardation, characteristic facial appearance (ektropion,skeletal abnormalities, joint laxity, short stature. The syndromeis thought to be a consequence of otosomal dominantmutation. Important factors in anesthetical managementof these patients include; difficult airway, cardiologicproblems, obstructive sleeps apne, hypotoni and malignshyperthermia risks. In this case report we aimed to discussanesthesic management of a patient with Kabukisyndrome -a rare clinical entity in our country- . J Clin ExpInvest 2013; 4 (1: 116-118Key words: kabuki makeup, tympanoplasty, general anesthesia

  5. Precise determination of refractometric parameters for anesthetic agent vapors.

    Science.gov (United States)

    Allison, J M; Birch, K P; Crowder, J G

    1994-05-01

    The absolute refractive indices of the anesthetic agent vapors isoflurane, sevoflurane, enflurane, halothane, and desflurane are determined to a typical uncertainty of 1 part in 10(7) over the respective temperature and pressure ranges of 15-40 °C and 5-45% of their saturated vapor pressures at wavelengths of 632.99, 594.10, and 543.52 nm. The specific refraction, second virial coefficients, and dispersion constants are also derived for each agent, from which an equation for the calculation of agent refractivity is established that is in agreement with the measured data to within 2 × 10(-8).

  6. [Anesthetic management of a patient with suspected pseudothrombocytopenia].

    Science.gov (United States)

    Hashimoto, Manabu; Kouchi, Akira; Inaba, Shin; Motomura, Yuji; Takahashi, Minoru

    2003-10-01

    A 74-year-old male was operated for sigmoid colon cancer. Because of an agglutination of the patient's platelet, it was difficult to measure his platelet count under ethylene diamine tetra acetate (EDTA), heparin or citrate as anticoagulants with an automated cell counter. Even though there was a strong possibility of pseudothrombocytopenia, anesthetic management for the patient was safely conducted. His condition was stable throughout the perioperative course and no bleeding tendency was observed. Nitrous oxide, oxygen, sevoflurane, propofol and pancuronium were useful in this case.

  7. Anesthetic considerations in Leigh disease: Case report and literature review

    Directory of Open Access Journals (Sweden)

    Abdullah Sulieman Terkawi

    2012-01-01

    Full Text Available Leigh disease is an extremely rare disorder, characterized by a progressive neurodegenerative course, with subacute necrotizing encephalomyelopathy. It usually presents in infancy with developmental delay, seizures, dysarthria, and ataxia. These patients may also develop episodes of lactic acidosis that usually lead to respiratory failure and death. Due to the rarity of the condition, the most appropriate anesthetic plan remains unclear. We present a patient with Leigh disease, who required general anesthesia. The pathogenesis of the disease is discussed and previous reports of perioperative care from the literature are reviewed.

  8. The environmental impact of the Glostavent® anesthetic machine.

    Science.gov (United States)

    Eltringham, Roger J; Neighbour, Robert C

    2015-06-01

    Because anesthetic machines have become more complex and more expensive, they have become less suitable for use in the many isolated hospitals in the poorest countries in the world. In these situations, they are frequently unable to function at all because of interruptions in the supply of oxygen or electricity and the absence of skilled technicians for maintenance and servicing. Despite these disadvantages, these machines are still delivered in large numbers, thereby expending precious resources without any benefit to patients. The Glostavent was introduced primarily to enable an anesthetic service to be delivered in these difficult circumstances. It is smaller and less complex than standard anesthetic machines and much less expensive to produce. It combines a drawover anesthetic system with an oxygen concentrator and a gas-driven ventilator. It greatly reduces the need for the purchase and transport of cylinders of compressed gases, reduces the impact on the environment, and enables considerable savings. Cylinder oxygen is expensive to produce and difficult to transport over long distances on poor roads. Consequently, the supply may run out. However, when using the Glostavent, oxygen is normally produced at a fraction of the cost of cylinders by the oxygen concentrator, which is an integral part of the Glostavent. This enables great savings in the purchase and transport cost of oxygen cylinders. If the electricity fails and the oxygen concentrator ceases to function, oxygen from a reserve cylinder automatically provides the pressure to drive the ventilator and oxygen for the breathing circuit. Consequently, economy is achieved because the ventilator has been designed to minimize the amount of driving gas required to one-seventh of the patient's tidal volume. Additional economies are achieved by completely eliminating spillage of oxygen from the breathing system and by recycling the driving gas into the breathing system to increase the Fraction of Inspired Oxygen

  9. Anesthetic management of schwannoma of the base of the tongue

    Directory of Open Access Journals (Sweden)

    Upma B Batra

    2011-01-01

    Full Text Available Schwannoma arising from the base of the tongue are very rare and only a few cases have been reported so far. Definitive diagnosis is always made after a histological examination. Apart from an anticipated difficult airway with a risk of airway obstruction upon induction of general anesthesia, anesthetic concerns also include possibility of trauma to the growth and bleeding with attendant risks. We discuss the awake fiberoptic technique used for endotracheal intubation in such a case. This case report highlights the importance of detailed history taking and clinical examination, with emphasis on airway assessment and preoperative planning.

  10. Anesthetic management of schwannoma of the base of the tongue.

    Science.gov (United States)

    Batra, Upma B; Usha, G; Gogia, Anoop R

    2011-04-01

    Schwannoma arising from the base of the tongue are very rare and only a few cases have been reported so far. Definitive diagnosis is always made after a histological examination. Apart from an anticipated difficult airway with a risk of airway obstruction upon induction of general anesthesia, anesthetic concerns also include possibility of trauma to the growth and bleeding with attendant risks. We discuss the awake fiberoptic technique used for endotracheal intubation in such a case. This case report highlights the importance of detailed history taking and clinical examination, with emphasis on airway assessment and preoperative planning.

  11. Positive Allosteric Modulation of Kv Channels by Sevoflurane: Insights into the Structural Basis of Inhaled Anesthetic Action.

    Directory of Open Access Journals (Sweden)

    Qiansheng Liang

    Full Text Available Inhalational general anesthesia results from the poorly understood interactions of haloethers with multiple protein targets, which prominently includes ion channels in the nervous system. Previously, we reported that the commonly used inhaled anesthetic sevoflurane potentiates the activity of voltage-gated K+ (Kv channels, specifically, several mammalian Kv1 channels and the Drosophila K-Shaw2 channel. Also, previous work suggested that the S4-S5 linker of K-Shaw2 plays a role in the inhibition of this Kv channel by n-alcohols and inhaled anesthetics. Here, we hypothesized that the S4-S5 linker is also a determinant of the potentiation of Kv1.2 and K-Shaw2 by sevoflurane. Following functional expression of these Kv channels in Xenopus oocytes, we found that converse mutations in Kv1.2 (G329T and K-Shaw2 (T330G dramatically enhance and inhibit the potentiation of the corresponding conductances by sevoflurane, respectively. Additionally, Kv1.2-G329T impairs voltage-dependent gating, which suggests that Kv1.2 modulation by sevoflurane is tied to gating in a state-dependent manner. Toward creating a minimal Kv1.2 structural model displaying the putative sevoflurane binding sites, we also found that the positive modulations of Kv1.2 and Kv1.2-G329T by sevoflurane and other general anesthetics are T1-independent. In contrast, the positive sevoflurane modulation of K-Shaw2 is T1-dependent. In silico docking and molecular dynamics-based free-energy calculations suggest that sevoflurane occupies distinct sites near the S4-S5 linker, the pore domain and around the external selectivity filter. We conclude that the positive allosteric modulation of the Kv channels by sevoflurane involves separable processes and multiple sites within regions intimately involved in channel gating.

  12. Effect of anesthetics on the radiosensitivity of a murine tumor

    Energy Technology Data Exchange (ETDEWEB)

    Sheldon, P.W.; Chu, A.M.

    1979-09-01

    The effect of four anesthetics on the single dose of x rays required to locally control 50% of implanted MT tumors was investigated. Compared with unanesthetized animals, no change in radiosensitivity was observed if mice were irradiated under either tribromoethanol or fentanyl-fluanisone-diazepam anesthesia. However, a small but significant degree of radioprotection was observed under chloral hydrate or pentobarbital anesthesia. Hypothermia or increased hypoxia are considered unlikely mechanisms for the protection, a direct chemical action being most probable. The preferred method for immobilizing the mice in order to locally irradiate the tumors was by simple physical restraint (with care taken to minimize physiological stress). However, if anesthesia was a necessity, the present work suggests that for the MT tumor at least the nonprotecting tribromoethanol and fentanyl-fluanisone-diazepam are preferable to the protecting chloral hydrate and pentobarbital. Tribromoethanol is preferable to fetanyl-fluanisone-diazepam in that it produces a smaller drop in temperature. However, it is only a short-acting anesthetic, and prolongation of the state of anesthesia by repeated doses simply prolongs the temperature decline so that there may be no real benefit over fentanyl-fluanisone-diazepam.

  13. [Anesthetic consideration in patients undergoing catheter ablation for atrial fibrillation].

    Science.gov (United States)

    Oda, Toshiyuki; Takahama, Yutaka

    2012-11-01

    This chapter describes anesthetic consideration in patients undergoing catheter ablation for atrial fibrillation (AF) based on electrophysiologic or pharmacological aspects. In the 2011 guidelines of the Japanese Circulation Society for non-pharmacotherapy of cardiac arrhythmias, catheter ablation is recommended as Class I therapeutic modality for the patients with drug-refractory paroxysmal AF. Catheter ablation of AF is an invasive and long-lasting procedure necessitating sedation during treatment. However, in the most of the patients, sedation or anesthesia is possibly performed by cardiologists using propofol, midazolam or dexmedetomidine. Deep sedation accompanies a high risk of ventilatory or circulatory derangement. Furthermore, life-threatening complications, such as cerebral infarction or cardiac tamponade, can occur during ablation. Patients with AF are increasing in number as a trend in the aging society, resulting in an increase in catheter ablation in high risk patients. To accomplish safe anesthetic management of the patients for catheter ablations, anesthesiologists are required to have fundamental knowledge and skill in the performance of the catheter ablation.

  14. Achieving pulpal anesthesia with a topical anesthetic paste

    Directory of Open Access Journals (Sweden)

    Bradley Carn

    2015-01-01

    Full Text Available Aim: The efficacy of a topically applied formulation of tetracaine base (6% was investigated against benzocaine in achieving pulpal anesthesia in a randomized, placebo-controlled, double-blind study. Materials and Methods: Subjects′ baseline pulpal responses to an electric pulp tester were measured, followed by a 10 min application of either tetracaine anesthetic paste (TAP, benzocaine (20%, or placebo. Treatments were removed and pulp testing was performed at 10 min, 15 min, and 20 min postapplication. Results: TAP produced significant pulpal anesthesia at 184% ± 7.2% above baseline versus 14% ± 1.7% above baseline for benzocaine at 15 min (P < 0.03. Differences between treatments were tested with the Wilcoxon test and the Steel-Dwass test, which is the nonparametric version of the all-pairs Tukey′s honestly significant difference test. Conclusion: Achieving profound anesthesia with a topical anesthetic paste could lead to injection less procedure, improved postsurgical incisional pain management, and ameliorate pain associated with a variety of lesions.

  15. Use of eutectic mixture of local anesthetics in children.

    Science.gov (United States)

    Dutta, S

    1999-01-01

    The Eutectic Mixture of Local Anesthetics (EMLA) is a topical application, which has proved to be a useful medication for providing pain relief among children. It is an emulsion containing a 1:1 mixture of lidocaine and prilocaine. The high concentration of the uncharged anesthetic base in the microdroplets of the emulsion ensure effective skin penetration. In the pediatric population EMLA has been shown to be efficacious when it is used prior to venipuncture, cannulation, lumbar puncture, laser treatment of port wine stains, curettage of molluscum contagiosum or vaccination. For several of these indications, the efficacy has been documented by double blind controlled trials, that have used objective and quasi-objective scales for assessing pain relief. The dose of EMLA is between 0.5 to 1 gram, and the cream should be applied half to one hour prior to the procedure. Local side effects are very mild, and the only systemic side effect of importance is the risk of methemoglobinemia in young infants. The literature has conflicting reports about the safety of EMLA in neonates.

  16. Electrocardiographic effects of toluene in the anesthetized rat.

    Science.gov (United States)

    Vidrio, H; Magos, G A; Lorenzana-Jimenez, M

    1986-01-01

    The influence of inhalation of near lethal quantities of toluene on some ECG parameters, as well as the possible cardiac sensitizing effect of the solvent, were determined in chloralose-anesthetized rats. These actions were compared with those of its close analogue benzene. Both solvents produced tachycardia; toluene increased the duration of QRS and specially PR, while benzene decreased P wave duration. No other systematic changes in ECG morphology or evidence of arrhythmia were observed. Toluene appeared to decrease the number of ectopic beats induced by epinephrine, in contrast to benzene, which increased it markedly. These results suggest that toluene administered by inhalation up to near lethal doses is devoid of untoward ECG effect in the chloralose-anesthetized rat, its only action being a decrease in intraventricular and particularly AV conduction. It does not share the myocardial sensitizing properties of benzene and in fact appears to elicit some protection from the arrhythmogenic effects of epinephrine, although no definite conclusions as to this action can be derived due to limitations in the experimental model used.

  17. Clinical application of thoracic paravertebral anesthetic block in breast surgeries

    Directory of Open Access Journals (Sweden)

    Sara Socorro Faria

    2015-04-01

    Full Text Available INTRODUCTION: Optimum treatment for postoperative pain has been of fundamental importance in surgical patient care. Among the analgesic techniques aimed at this group of patients, thoracic paravertebral block combined with general anesthesia stands out for the good results and favorable risk-benefit ratio. Many local anesthetics and other adjuvant drugs are being investigated for use in this technique, in order to improve the quality of analgesia and reduce adverse effects. OBJECTIVE: Evaluate the effectiveness and safety of paravertebral block compared to other analgesic and anesthetic regimens in women undergoing breast cancer surgeries. METHODS: Integrative literature review from 1966 to 2012, using specific terms in computerized databases of articles investigating the clinical characteristics, adverse effects, and beneficial effects of thoracic paravertebral block. RESULTS: On the selected date, 16 randomized studies that met the selection criteria established for this literature review were identified. Thoracic paravertebral block showed a significant reduction of postoperative pain, as well as decreased pain during arm movement after surgery. CONCLUSION: Thoracic paravertebral block reduced postoperative analgesic requirement compared to placebo group, markedly within the first 24 h. The use of this technique could ensure postoperative analgesia of clinical relevance. Further studies with larger populations are necessary, as paravertebral block seems to be promising for preemptive analgesia in breast cancer surgery.

  18. Scientometrics of anesthetic drugs and their techniques of administration, 1984–2013

    Directory of Open Access Journals (Sweden)

    Vlassakov KV

    2014-12-01

    Full Text Available Kamen V Vlassakov, Igor Kissin Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA Abstract: The aim of this study was to assess progress in the field of anesthetic drugs over the past 30 years using scientometric indices: popularity indices (general and specific, representing the proportion of articles on a drug relative to all articles in the field of anesthetics (general index or the subfield of a specific class of anesthetics (specific index; index of change, representing the degree of growth in publications on a topic from one period to the next; index of expectations, representing the ratio of the number of articles on a topic in the top 20 journals relative to the number of articles in all (>5,000 biomedical journals covered by PubMed; and index of ultimate success, representing a publication outcome when a new drug takes the place of a common drug previously used for the same purpose. Publications on 58 topics were assessed during six 5-year periods from 1984 to 2013. Our analysis showed that during 2009–2013, out of seven anesthetics with a high general popularity index (≥2.0, only two were introduced after 1980, ie, the inhaled anesthetic sevoflurane and the local anesthetic ropivacaine; however, only sevoflurane had a high index of expectations (12.1. Among anesthetic adjuncts, in 2009–2013, only one agent, sugammadex, had both an extremely high index of change (>100 and a high index of expectations (25.0, reflecting the novelty of its mechanism of action. The index of ultimate success was positive with three anesthetics, ie, lidocaine, isoflurane, and propofol, all of which were introduced much longer than 30 years ago. For the past 30 years, there were no new anesthetics that have produced changes in scientometric indices indicating real progress. Keywords: anesthetics, anesthetic adjuvants, mortality, safety margins, therapeutic indices

  19. Dual effect of local anesthetics on the function of excitable rod outer segment disk membrane

    Energy Technology Data Exchange (ETDEWEB)

    Mashimo, T.; Abe, K.; Yoshiya, I.

    1986-04-01

    The effects of local anesthetics and a divalent cation, Ca2+, on the function of rhodopsin were estimated from the measurements of light-induced proton uptake. The light-induced proton uptake by rhodopsin in the rod outer segment disk membrane was enhanced at lower pH (4) but depressed at higher pHs (6 to 8) by the tertiary amine local anesthetics lidocaine, bupivacaine, tetracaine, and dibucaine. The order of local anesthetic-induced depression of the proton uptake followed that of their clinical anesthetic potencies. The depression of the proton uptake versus the concentration of the uncharged form of local anesthetic nearly describes the same curve for small and large dose of added anesthetic. Furthermore, a neutral local anesthetic, benzocaine, depressed the proton uptake at all pHs between 4 and 7. These results indicate that the depression of the proton uptake is due to the effect of only the uncharged form. It is hypothesized that the uncharged form of local anesthetics interacts hydrophobically with the rhodopsin in the disk membrane. The dual effect of local anesthetics on the proton uptake, on the other hand, suggests that the activation of the function of rhodopsin may be caused by the charged form. There was no significant change in the light-induced proton uptake by rhodopsin when 1 mM of Ca2+ was introduced into the disk membrane at varying pHs in the absence or presence of local anesthetics. This fact indicates that Ca2+ ion does not influence the diprotonating process of metarhodopsin; neither does it interfere with the local anesthetic-induced changes in the rhodopsin molecule.

  20. Stochastic volatility and stochastic leverage

    DEFF Research Database (Denmark)

    Veraart, Almut; Veraart, Luitgard A. M.

    This paper proposes the new concept of stochastic leverage in stochastic volatility models. Stochastic leverage refers to a stochastic process which replaces the classical constant correlation parameter between the asset return and the stochastic volatility process. We provide a systematic...... treatment of stochastic leverage and propose to model the stochastic leverage effect explicitly, e.g. by means of a linear transformation of a Jacobi process. Such models are both analytically tractable and allow for a direct economic interpretation. In particular, we propose two new stochastic volatility...... models which allow for a stochastic leverage effect: the generalised Heston model and the generalised Barndorff-Nielsen & Shephard model. We investigate the impact of a stochastic leverage effect in the risk neutral world by focusing on implied volatilities generated by option prices derived from our new...

  1. Anesthetic success of 1.8ml lidocaine 2% for mandibular tooth extraction. A pilot study

    Directory of Open Access Journals (Sweden)

    Pedro Aravena

    2013-04-01

    Full Text Available Aim: To determine the anesthetic effect of a 1.8ml cartridge of anesthetic lidocaine 2% with epinephrine 1:100,000 in inferior alveolar nerve block (NAI for the extraction in mandibular teeth. Material and methods: A pilot study with analitic design. Participating patients of Dental Emergency Service volunteers from Valdivia-Chile for mandibular teeth extractions attending between May and July of 2010. The anesthetic technique was performed by a dentist using only one cartridge of anesthetic to the NAI. After 15 minutes, the effect was considered effective when anesthetic not require reinforcement with additional anesthesia during extraction of teeth. We analyzed the relationship between success anesthetic effect with sex, age, diagnosis of tooth and type and level of pain observed (chi-square and logistic regression, p<0.05. Results: 62 patients were selected, of which only 47(75.8% was achieved anesthetic success. There was no statistical association with sex, age, type or dental diagnosis and perceived pain. Conclusion: Using a 1.8ml cartridge of anesthesia was effective in three of four patients treated by extraction of mandibular teeth. It suggests further research in relation to the clinical effectiveness of other anesthetics with the same dose in NAI.

  2. [Anesthetic machine leakage from vaporizer by external force derived from keyboard of electronic medical records].

    Science.gov (United States)

    Ikegami, Hiromi; Goto, Ryokichi; Sakamoto, Syotarou; Kohama, Hanako

    2012-11-01

    We experienced the leakage from the vaporizer of the anesthetic machine despite the normalities on performing the initial leak test. The vaporizer of the anesthetic machine was compressed by computer keyboard of EMR which caused a leak from vaporizer. After computer keyboard and the vaporizer were set at normal position, the leak stopped.

  3. Bupivacaine Lozenge Compared with Lidocaine Spray as Topical Pharyngeal Anesthetic before Unsedated Upper Gastrointestinal Endoscopy

    DEFF Research Database (Denmark)

    Salale, Nesrin; Treldal, Charlotte; Mogensen, Stine;

    2014-01-01

    Unsedated upper gastrointestinal endoscopy (UGE) can induce patient discomfort, mainly due to a strong gag reflex. The aim was to assess the effect of a bupivacaine lozenge as topical pharyngeal anesthetic compared with standard treatment with a lidocaine spray before UGE. Ninety-nine adult...... with a lidocaine spray proved to be a superior option as topical pharyngeal anesthetic before an UGE....

  4. A Comparison of Hamster Anesthetics and Their Effect on Mosquito Blood Feeding

    Science.gov (United States)

    Hamsters or mice are often anesthetized when they are used as the hosts for insect feeding experiments. An experiment was done to determine if there was a difference in mosquito blood feeding success when fed on hamsters anesthetized using two commonly used protocols. The number of blood-fed females...

  5. On forecasting Exchange Rate Volatility.

    OpenAIRE

    Hafner, Christian

    2003-01-01

    In an efficient market, foreign exchange rates have to guarantee absence of triangular arbitrage. This note shows that the no-arbitrage condition can be exploited for forecasting the volatility of a single rate by using the information contained in the other rates. Linearly transforming the volatility forecasts of a bivariate model is shown to be more efficient than using a univariate model for the cross-rate.

  6. Mimicking anesthetic-receptor interactions in jets: the propofol-isopropanol cluster.

    Science.gov (United States)

    León, Iker; Usabiaga, Imanol; Millán, Judith; Cocinero, Emilio J; Lesarri, Alberto; Fernández, José A

    2014-08-28

    The interaction of the general anesthetic propofol with an individual residue of threonine in the membrane receptors has been modeled in the gas phase by examining the adduct of propofol with the isopropanol side-chain. We determined the structural preferences of the cluster using a combination of mass-resolved laser spectroscopy and quantum mechanical calculations. The first electronic transition of propofol-isopropanol was recorded with vibrational resolution using resonant two-photon ionization (R2PI) and ion dip IR spectroscopy. The spectra obtained were compared with density-functional calculations (DFT) using the M06-2X functional in order to obtain the cluster's structure. Three isomers have been detected. The results suggest that propofol acts as a Brønsted acid, donating a proton to the isopropanol molecule in a conformation that resembles that of propofol-water, but displaced towards the aromatic ring, due to the interaction with the aliphatic side of isopropanol. The higher affinity of propofol for isopropanol compared to water may correlate with the biological role of propofol at the protein binding site. On the other hand, propofol shows a similar affinity for isopropanol and phenol, which could explain the mobility that propofol experiences inside the GABAA cavity.

  7. Nonpreserved amniotic membrane transplantation for bilateral toxic keratopathy caused by topical anesthetic abuse: a case report

    Directory of Open Access Journals (Sweden)

    Altinok Ayse

    2010-08-01

    Full Text Available Abstract Introduction Corneal damage associated with abuse of topical anesthetics is a rare clinic entity. Topical anesthetic abuse is one of the causes of ring keratitis. Ring keratitis is easily overlooked because it can mimic acanthamoeba keratitis or other infectious keratitis. The outcome is often poor, leading to persistent epithelial defects, corneal scarring, and perforations. Case presentation We report the clinical presentation, diagnosis, and treatment of a 65-year-old Caucasian man, who worked as a health care worker, with bilateral toxic keratopathy caused by topical anesthetic abuse. Nonpreserved amniotic membrane transplantation was performed for both eyes of the patient. Conclusion It is important to identify and treat patients who abuse topical anesthetics before permanent vision loss ensues. Nonpreserved amniotic membrane transplantation may be useful in relieving pain and improving corneal surface in anesthetic agent abusers.

  8. Opposing effects of the anesthetic propofol at pentameric ligand-gated ion channels mediated by a common site

    DEFF Research Database (Denmark)

    Lynagh, Timothy Peter; Laube, Bodo

    2014-01-01

    Propofol is an intravenous general anesthetic that alters neuronal excitability by modulating agonist responses of pentameric ligand-gated ion channels (pLGICs). Evidence suggests that propofol enhancement of anion-selective pLGICs is mediated by a binding site between adjacent subunits, whereas...... in Xenopus laevis oocytes with electrophysiology. The Haemonchus contortus AVR-14B GluCl was inhibited by propofol with an IC50 value of 252 ± 48 μM, providing the first example of propofol inhibition of an anion-selective pLGIC. Remarkably, inhibition was converted to enhancement by a single I18'S...... substitution in the channel-forming M2 helix (EC50 = 979 ± 88 μM). When a previously identified site between adjacent subunits was disrupted by the M3 G329I substitution, both propofol inhibition and enhancement of GluCls were severely impaired (IC50 and EC50 values could not be calculated). Similarly, when...

  9. Recent Advances in Volatiles of Teas

    Directory of Open Access Journals (Sweden)

    Xin-Qiang Zheng

    2016-03-01

    Full Text Available Volatile compounds are important components of tea aroma, a key attribute of sensory quality. The present review examines the formation of aromatic volatiles of various kinds of teas and factors influencing the formation of tea volatiles, including tea cultivar, growing environment and agronomic practices, processing method and storage of tea. The determination of tea volatiles and the relationship of active-aroma volatiles with the sensory qualities of tea are also discussed in the present paper.

  10. Anesthetic management of Morgagni hernia repair in an elderly woman.

    Science.gov (United States)

    Nama, Rajnish K; Butala, Bina P; Shah, Veena R; Patel, Hiren R

    2015-01-01

    Adult onset congenital diaphragmatic hernia (CDH) is uncommon but not rare. Morgagni hernia is a rare variant of CDH. The defect tends to be small and patients may remain asymptomatic and diagnosed incidentally. When these patients become symptomatic, they usually present with gastrointestinal and cardiorespiratory symptoms or sometimes as an emergency due to obstruction or strangulation of herniated viscera. Chest radiograph, computed tomography scan, and magnetic resonance imaging are the imaging modalities used for diagnosis of CDH. Cardiopulmonary compromise due to mass effect of hernial contents on lungs, heart and great vessels, and obstruction or strangulation of herniated viscera poses the special challenge before anesthesiologists. Our patient was diagnosed to have Morgagni hernia, at the age of 72 years and underwent laparotomy for the same. This case highlights the key feature of the successful anesthetic management of adult onset CDH.

  11. Dental anesthetic management of a patient with ventricular arrhythmias.

    Science.gov (United States)

    Miller, R A; Siegelman, L I

    1998-01-01

    During routine deep sedation for endodontic therapy, a dentist-anesthesiologist observed premature ventricular contractions (PVCs) on a 62-yr-old woman's electrocardiogram (EKG) tracing. The dentist was able to complete the root canal procedure under intravenous (i.v.) sedation without any problems. The dentist-anesthesiologist referred the patient for medical evaluation. She was found to be free from ischemic cardiac disease with normal ventricular function. The patient was cleared to continue her dental treatment with deep sedation. She subsequently continued to undergo dental treatment with deep intravenous sedation without incident, although her EKG exhibited frequent PVCs, up to 20 per minute, including couplets and episodes of trigeminy. This article will review indications for medical intervention, antiarrhythmic medications, and anesthetic interventions for perioperative PVCs.

  12. Neurotoxicity of general anesthetics: A modern view of the problem

    Directory of Open Access Journals (Sweden)

    A. M. Ovezov

    2015-01-01

    Full Text Available All general anesthetics routinely used in clinical practice are noted to have a neurotoxic effect on the brain in different animal species including primates. The negative effects observed both in young and sexually mature animals include apoptotic neuronal cell death, suppression of neurogenesis and gliogenesis, neuroinflammation, as well as learning and memory impairments. A number of epidemiologic surveys have established an association between anesthesia in patients younger than 3 to 4 years and subsequent learning disabilities and language disorders whereas others have not found this link. In middle-aged and elderly patients, anesthesia is frequently associated with the development of postoperative cognitive dysfunction. The key component of its pathogenesis (general anesthesia itself or other factors, such as operative injury, an inflammatory response, pain syndrome, intraoperative complications, underlying disease in a patient remains unelucidated. It is concluded that there is a need for additional experimental and clinical studies of the pathogenesis of these undesirable phenomena to be prevented and corrected.

  13. Eugenol as an anesthetic for juvenile common snook

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    Jurandir Joaquim Bernardes Júnior

    2013-08-01

    Full Text Available The objective of this work was to evaluate the efficacy of eugenol as an anesthetic for juvenile common snook, and to determine the minimum effective concentration for use in handling procedures. In the first trial, juvenile common snook were subjected to immersion baths at 25, 50, 75, 100, 125, and 150 mg L-1 eugenol concentrations, after which induction and recovery times were evaluated. In the second experiment, the lethal exposure time (LT50 at 75 mg L-1 was estimated. Minimum effective eugenol concentration was 50 mg L-1, andthe stage of deep anesthesia and recovery were, respectively, reached at 126.3 and 208.8 s. At 75 mg L-1, LT50 was 1,314 s, and induction time and recovery were also satisfactory; however, fish cannot tolerate over 229 s exposure.

  14. Electrocardiographic evaluation of two anesthetic combinations in dogs

    Directory of Open Access Journals (Sweden)

    Tárraga K.M.

    2000-01-01

    Full Text Available This study aimed to investigate electrocardiographic changes in dogs aged 5 years or more submitted to two anesthetic combinations: atropine, levomeprazine, thiopental and halothane (ALTH, and atropine, tiletamine and zolazepam (ATZ. Forty dogs (24 males/16 females weighing 5-24kg, were used. Dogs had no cardiac problems and were submitted to tartarectomy. All animals were submitted to two electrocardiograms (ECG, one before anesthesia and other immediately before surgery. The dogs were divided into two groups: group 1 received ALTH and group 2 received ATZ. Alterations in the ST segment, T wave, cardiac rhythm and a significant reduction of vagal tonus index were observed in both groups, but in group 2 a significant reduction of the PR and QT intervals and an increase in heart rate were also observed. These data suggest that the ALTH combination caused fewer changes in the ECG than the ATZ combination.

  15. Carcinoid tumors: Challenges and considerations during anesthetic management

    Directory of Open Access Journals (Sweden)

    Sukhminder Jit Singh Bajwa

    2015-01-01

    Full Text Available Carcinoid tumors are rare, slow-growing neoplasms of neuroendocrine tissues from enterochromaffin or kulchitsky cells, which have the potential to metastasize. The mediators released from these tumors when bypass the hepatic metabolism, can lead to the possible development of carcinoid syndrome. This is a life-threatening complication, which can lead to profound hemodynamic instability, especially in a peri-operative period, when the patient is exposed to various types of noxious stimuli. Off late, use of octreotide, a synthetic analog of somatostatin, has significantly reduced the peri-operative morbidity and mortality. The current review discusses the various anesthetic challenges and considerations during peri-operative management of carcinoid tumors.

  16. Anesthetic management of robot-assisted thoracoscopic thymectomy

    Directory of Open Access Journals (Sweden)

    Anil Karlekar

    2016-01-01

    Full Text Available Myasthenia gravis (MG is a rare disorder involving neuromuscular junction. In conjunction with medical therapy, thymectomy is a known modality of treatment of MG and has shown to increase the probability of remission and overall symptomatic improvement. For minimally invasive thymectomy, video-.assisted thoracoscopic surgery has been the preferred surgical approach till recently. The robotic surgical procedure must necessarily bring new challenges to the anesthesiologists to effectively meet the specific requirements of the technique. At present, there is a paucity of literature regarding the anesthetic concerns of robotic assisted thymectomy, patient in question specifically posed a challenge since different maneuvers and techniques had to be tried to obtain optimum surgical conditions with stable ventilatory and hemodynamic parameters. Concerns of patient positioning and hemodynamic monitoring have also been discussed.

  17. Use of pethidine as an intravenous regional anesthetic.

    Science.gov (United States)

    el-Bakry, M S; el-Shafei, S B; Seyam, E M; el-Kobbia, N M; Ebrahim, U H

    1989-06-01

    Pethidine 100 mg in 30-40 ml saline was given in a group of patients by the conventional technique of intravenous regional anesthesia. Fourty percent of the patients did not feel any form of pain or discomfort, 26.7% experienced only vague sensations which did not call for additional drugs but 13.3% felt some form of pain or discomfort for which diazepam was given and was enough for surgery to be completed. In the rest of the patients (20%) there was intolerable pain for which patients were given general anesthesia. This last category was operated upon for recent fractures or digital conditions and it is known that intravenous regional anesthesia using conventional local anesthetics for such patients usually fails. In a control group in which 30-40 ml saline without pethidine were injected, there was complete failure of the technique.

  18. Epidermolysis Bullosa, Dental and Anesthetic Management: A Case Report

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    Katayoun Esfahanizadeh

    2014-09-01

    Full Text Available Epidermolysis bullosa (EB is a group of rare inherited skin and mucous membrane disorders in which blister formation may arise spontaneously or following a minor friction. Various patterns of inheritance are explicated for the disease. The disease has a profound effect on oral mucosa and may result in high prevalence of dental caries. General anesthesia is sometimes the only choice for dental treatments in patients with EB. The following case report describes the dental and anesthetic management of an 12.5 -year-old girl with dystrophic type of EB. The patient was followed up every 6 months. New carious lesions were detected one year after the treatment, on the last visit. Presenting a perfect dental care to children with this disorder can be challenging for the in charge specialist, both pediatric dentist and anesthesiologist.

  19. Epidermolysis bullosa, dental and anesthetic management: a case report.

    Science.gov (United States)

    Esfahanizade, Katayoun; Mahdavi, Ali Reza; Ansari, Ghassem; Fallahinejad Ghajari, Masoud; Esfahanizadeh, Abdolreza

    2014-09-01

    Epidermolysis bullosa (EB) is a group of rare inherited skin and mucous membrane disorders in which blister formation may arise spontaneously or following a minor friction. Various patterns of inheritance are explicated for the disease. The disease has a profound effect on oral mucosa and may result in high prevalence of dental caries. General anesthesia is sometimes the only choice for dental treatments in patients with EB. The following case report describes the dental and anesthetic management of an 12.5 -year-old girl with dystrophic type of EB. The patient was followed up every 6 months. New carious lesions were detected one year after the treatment, on the last visit. Presenting a perfect dental care to children with this disorder can be challenging for the in charge specialist, both pediatric dentist and anesthesiologist.

  20. Anticholeretic effect of substance P in anesthetized dogs.

    Science.gov (United States)

    Holm, I; Thulin, L; Hellgren, M

    1978-03-01

    Nine anesthetized dogs were provided with acute common duct fistulas after exclusion of the gallbladder. Synthetic Substance P was administered as caval infusions in a dosage of 0.5-20 ng x kg-1 x min-1, duration 10 min. The output of hepatic bile, sodium and amylase decreased during infusion by 40-52 per cent at the highest doses. After termination of infusion all 3 parameters increased by 19-60 per cent above the basal level. The biliary concentration of sodium was constant, while that of amylase increased during infusion. The responses were dose-related. The anticholeresis induced by substance P might be due to inhibition of the canalicular bile fraction, which presumably is mediated by active sodium transport and independent of bile salt excretion.

  1. The effects of anesthetic agents on oxidative stress

    Science.gov (United States)

    Yakan, Selvinaz; Düzgüner, Vesile

    2016-04-01

    Oxidative stress can be defined as the instability between antioxidant defense of the body and the production of free radical that causes peroxydation on the lipid layer. Free radicals are reactive oxygen species that are produced in the course of normal metabolisms of aerobe organisms and they may cause disorders in cell structure and organelles by interacting macromolecules, like lipid, protein, nucleic acids. Therefore, they may cause cardiovascular, immune system, liver, kidney illnesses and many other illnesses like cancer, aging, cataract, diabetes. It is known that many drugs used for the purpose of anesthetizing may cause lipid peroxidation in organism. For these reasons, determining the Oxidative stress index of anaesthetic stress chosen in the ones that are exposed to long term anaesthetic agents and anaesthesia appliccations, is so substantial.

  2. Anesthetic management of laparoscopic pheochromocytoma surgery: A case report

    Directory of Open Access Journals (Sweden)

    Hakan Akelma

    2014-06-01

    Full Text Available Pheochromocytoma is a neuroendocrine tumor of the adrenal medulla chromaffin cells. It has a variable clinic indicating symptoms such as hypertension, headache, sweating, palpitations, and anxiety. Determination of vanillylmandelic acid in urine and metanephrines are accepted as the most sensitive tests for diagnosis. Computerized tomography and magnetic resonance imaging cad be used for tumor localization. Anesthetic induction and surgical manipulations usually lead to the catastrophic release of catecholamines. Thus, accurate preoperative pharmacological preparation is vital in these patients. Treatment is a complete surgical resection of the primary tumor and, if possible, metastases after banning dangerous fluctuations in hemodynamic through α-blockers. Today, laparoscopic adrenalectomy has begun to replace open surgery as a standard treatment method in many adrenal diseases. J Clin Exp Invest 2014; 5 (2: 443-446

  3. Under Utilization of Local Anesthetics in Infant Lumbar Punctures

    Directory of Open Access Journals (Sweden)

    Gorchynski, Julie

    2008-01-01

    Full Text Available Background: Lumbar Puncture (LP is an invasive procedure frequently used to diagnose meningitis among the pediatric population. Neonates and infants have not routinely received local anesthesia prior to LP. Study Objective: To determine whether emergency medicine physicians and pediatricians use local analgesics on neonates and infants prior to performing an LP and to identify which local anesthetics, if any, were used. Methods: Prospective, cohort study of all infants, six months of age or less, that received an LP in the emergency department (ED or inpatient pediatric units for suspected meningitis during a period of year at a university tertiary care hospital. Results: A total sample population of 111 infants that received an LP within the study period. A control population of 42 adults received an LP. Only 40.4% (45/111 of the infants received local analgesia prior to LP: either 1% lidocaine, EMLA or a combination of the two. Infants were less likely to receive lidocaine or EMLA prior to LP compared to adult subjects (OR= 0.27; 95% CI0.12 to 0.62. No neonates that were less than one month of age received local procedural anesthesia by emergency medicine or pediatric physicians. ED physicians’ use of local anesthesia prior to LP increased with increasing age of the infant. The pediatricians in this study used local anesthesia prior to LP when the infant was at least five months of age. Discussion: The data objectively support recent literature regarding the under use or lack of use of analgesia prior to LP among neonates and infants. Local anesthetics should be used routinely without exception prior to performing an LP in the pediatric population.

  4. Binding Procurement

    Science.gov (United States)

    Rao, Gopalakrishna M.; Vaidyanathan, Hari

    2007-01-01

    This viewgraph presentation reviews the use of the binding procurement process in purchasing Aerospace Flight Battery Systems. NASA Engineering and Safety Center (NESC) requested NASA Aerospace Flight Battery Systems Working Group to develop a set of guideline requirements document for Binding Procurement Contracts.

  5. Spiral mining for lunar volatiles

    Science.gov (United States)

    Schmitt, H. H.; Kulcinski, G. L.; Sviatoslavsky, I. N.; Carrier, W. D., III

    Lunar spiral mining, extending outward from a periodically mobile central power and processing station represents an alternative for comparison with more traditional mining schemes. In this concept, a mining machine would separate regolith fines and extract the contained volatiles. Volatiles then would be pumped along the miner's support arm to the central station for refining and for export or storage. The basic architecture of the central processing station would be cylindrical. A central core area could house the power subsystem of hydrogen-oxygen engines or fuel cells. Habitat sections and other crew occupied areas could be arranged around the power generation core. The outer cylinder could include all volatile refining subsystems. Solar thermal power collectors and reflectors would be positioned on top of the central station. Long term exploitation of a volatile resource region would begin with establishment of a support base at the center of a long boundary of the region. The mining tract for each spiral mining system would extend orthogonal to this boundary. New spiral mining systems would be activated along parallel tracts as demand for lunar He-3 and other solar wind volatiles increased.

  6. The price of fixed income market volatility

    CERN Document Server

    Mele, Antonio

    2015-01-01

    Fixed income volatility and equity volatility evolve heterogeneously over time, co-moving disproportionately during periods of global imbalances and each reacting to events of different nature. While the methodology for options-based "model-free" pricing of equity volatility has been known for some time, little is known about analogous methodologies for pricing various fixed income volatilities. This book fills this gap and provides a unified evaluation framework of fixed income volatility while dealing with disparate markets such as interest-rate swaps, government bonds, time-deposits and credit. It develops model-free, forward looking indexes of fixed-income volatility that match different quoting conventions across various markets, and uncovers subtle yet important pitfalls arising from naïve superimpositions of the standard equity volatility methodology when pricing various fixed income volatilities. The ultimate goal of the authors´ efforts is to make interest rate volatility standardization a valuable...

  7. Occupational disease in dentistry and chronic exposure to trace anesthetic gases.

    Science.gov (United States)

    Cohen, E N; Gift, H C; Brown, B W; Greenfield, W; Wu, M L; Jones, T W; Whitcher, C E; Driscoll, E J; Brodsky, J B

    1980-07-01

    A mail survey of 30,650 dentists and 30,547 chairside assistants grouped according to occupational exposure to inhalation anesthetic and sedatives in the dental operatory indicated increased general health problems and reproductive difficulties among respondents exposed to anesthetics. For male dentists who were heavily exposed to anesthetics, the increase in liver disease was 1.7-fold, kidney disease was 1.2-fold, and neurological disease was 1.9-fold. For wives of male dentists who were heavily exposed to anesthetics, the increase in spontaneous abortion rate was 1.5-fold. Among female chairside assistants who were heavily exposed to anesthetics, the increase in liver disease was 1.6-fold, kidney disease was 1.7-fold, and neurological disease was 2.8-fold. The increase in spontaneous abortion rate among assistants who were heavily exposed was 2.3-fold. Cancer rates in women heavily exposed to inhalation anesthetics were increased 1.5-fold but this finding was not statistically significant (P = .06). Separate analysis of the data for disease rates and birth difficulties by type of inhalation anesthetic indicates that in both dentists and chairside assistants chronic exposure to nitrous oxide alone is associated with an increase rate of adverse response.

  8. Anesthetic effects of a three-drugs mixture--comparison of administrative routes and antagonistic effects of atipamezole in mice.

    Science.gov (United States)

    Kirihara, Yumiko; Takechi, Mayumi; Kurosaki, Kaoru; Kobayashi, Yuta; Saito, Yoji; Takeuchi, Takashi

    2015-01-01

    The anesthetic mixture of medetomidine (MED), midazolam (MID) and butorphanol (BUT) produced anesthetic duration of around 40 minutes (min) in ICR mice. We reported that this anesthetic mixture produced almost the same anesthetic effects in both male and female BALB/c and C57BL/6J strains. Intraperitoneal (IP) administration of drugs has been widely used in mice. However, various injectable routes of the anesthetic mixture may cause different anesthetic effects. First, we examined effects of the anesthetic mixture by subcutaneous (SC) and intravenous (IV) injection compared to IP injection. After injection of the anesthetic mixture, administration of atipamezole (ATI) induced mice recovery from anesthesia. Secondly, we examined how different dosage and optimum injection timing of ATI affected mice recovery from anesthesia. We used an anesthetic score to measure anesthetic duration and a pulse oximeter to monitor vital signs under anesthesia. Usually, drugs from SC injection work more weakly than IP or IV injection. However, we found no significant differences of anesthetic duration among the three different injection routes. Antagonistic effects of ATI (0.3 mg/kg and 1.5 mg/kg) worked equally when administered at 30 min after injection of the anesthetic mixture. Antagonistic effects of ATI (1.5 mg/kg) were stronger than ATI (0.3 mg/kg) at 10 min after injection of the anesthetic mixture. The anesthetic mixture is a useful drug to induce nearly the same anesthetic effects by different injection routes and has an antagonist of ATI which helps mice quickly recover from anesthesia. These results may contribute to the welfare of laboratory animals.

  9. Observability of market daily volatility

    Science.gov (United States)

    Petroni, Filippo; Serva, Maurizio

    2016-02-01

    We study the price dynamics of 65 stocks from the Dow Jones Composite Average from 1973 to 2014. We show that it is possible to define a Daily Market Volatility σ(t) which is directly observable from data. This quantity is usually indirectly defined by r(t) = σ(t) ω(t) where the r(t) are the daily returns of the market index and the ω(t) are i.i.d. random variables with vanishing average and unitary variance. The relation r(t) = σ(t) ω(t) alone is unable to give an operative definition of the index volatility, which remains unobservable. On the contrary, we show that using the whole information available in the market, the index volatility can be operatively defined and detected.

  10. Rhenium volatilization in waste glasses

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Kai; Pierce, David A. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Hrma, Pavel, E-mail: pavel.hrma@pnnl.gov [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Schweiger, Michael J. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Kruger, Albert A. [U.S. Department of Energy, Office of River Protection, Richland, WA 99352 (United States)

    2015-09-15

    Highlights: • Re did not volatilize from a HLW feed until 1000 °C. • Re began to volatilize from LAW feeds at ∼600 °C. • The vigorous foaming and generation of gases from salts enhanced Re evaporation in LAW feeds. • The HLW glass with less foaming and salts is a promising medium for Tc immobilization. - Abstract: We investigated volatilization of rhenium (Re), sulfur, cesium, and iodine during the course of conversion of high-level waste melter feed to glass and compared the results for Re volatilization with those in low-activity waste borosilicate glasses. Whereas Re did not volatilize from high-level waste feed heated at 5 K min{sup −1} until 1000 °C, it began to volatilize from low-activity waste borosilicate glass feeds at ∼600 °C, a temperature ∼200 °C below the onset temperature of evaporation from pure KReO{sub 4}. Below 800 °C, perrhenate evaporation in low-activity waste melter feeds was enhanced by vigorous foaming and generation of gases from molten salts as they reacted with the glass-forming constituents. At high temperatures, when the glass-forming phase was consolidated, perrhenates were transported to the top surface of glass melt in bubbles, typically together with sulfates and halides. Based on the results of this study (to be considered preliminary at this stage), the high-level waste glass with less foaming and salts appears a promising medium for technetium immobilization.

  11. Oil Volatility Risk and Expected Stock Returns

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Pan, Xuhui (Nick)

    After the financialization of commodity futures markets in 2004-05 oil volatility has become a strong predictor of returns and volatility of the overall stock market. Furthermore, stocks' exposure to oil volatility risk now drives the cross-section of expected returns. The difference in average...... return between the quintile of stocks with low exposure and high exposure to oil volatility is significant at 0.66% per month, and oil volatility risk carries a significant risk premium of -0.60% per month. In the post-financialization period, oil volatility risk is strongly related with various measures...

  12. Anesthetic management of a parturient with Guillain-Barre syndrome posted for emergency caesarian section

    Directory of Open Access Journals (Sweden)

    Abhijit Paul

    2012-01-01

    Full Text Available We report the anesthetic management of a case of Guillain-Barre syndrome in the 34 th week of gestation coming for an emergency Cesarean section. The perioperative anesthetic challenges have been discussed with emphasis on the medical and anesthetic management which includes the use of plasma-pheresis, intravenous gamma-globulin, and the safety of preservative free 0.75% isobaric ropivacaine, which was administered intrathecally in this difficult medical condition with excellent hemodynamic, maternal, and fetal outcome. The sensory and motor blocks achieved were well suited to the clinical risks and conditions.

  13. Anesthetic management of a large mediastinal mass for tracheal stent placement

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    Suman Rajagopalan

    2016-04-01

    Full Text Available ABSTRACT The anesthetic management of patients with large mediastinal masses can be complicated due to the pressure effects of the mass on the airway or major vessels. We present the successful anesthetic management of a 64-year-old female with a large mediastinal mass that encroached on the great vessels and compressed the trachea. A tracheal stent was placed to relieve the tracheal compression under general anesthesia. Spontaneous ventilation was maintained during the perioperative period with the use of a classic laryngeal mask airway. We discuss the utility of laryngeal mask airway for anesthetic management of tracheal stenting in patients with mediastinal masses.

  14. Synthesis and antispasmodic activity of lidocaine derivatives endowed with reduced local anesthetic action.

    Science.gov (United States)

    Costa, Jorge C S; Neves, Josiane S; de Souza, Marcus V N; Siqueira, Rodrigo A; Romeiro, Nelilma C; Boechat, Nubia; e Silva, Patrícia M R; Martins, Marco A

    2008-02-01

    The present structure-activity relationship (SAR) study focused on chemical modifications of the structure of the local anesthetic lidocaine, and indicated analogues having reduced anesthetic potency, but with superior potency relative to the prototype in preventing anaphylactic or histamine-evoked ileum contraction. From the SAR analysis, 2-(diethylamino)-N-(trifluoromethyl-phenyl) and 2-(diethylamino)-N-(dimethyl-phenyl) acetamides were selected as the most promising compounds. New insights into the applicability of non-anesthetic lidocaine derivatives as templates in drug discovery for allergic syndromes are provided.

  15. An improved method for lifting and transporting anesthetized pigs within an animal facility

    DEFF Research Database (Denmark)

    Schumacher-Petersen, Camilla; Hammelev, Karsten Pharao; Flescher, Jens Erik

    2014-01-01

    Transporting anesthetized pigs in a laboratory setting often requires strenuous manual lifting, posing a hazard to the safety of animal care personnel and to the welfare of the pigs. The authors developed an improved approach to lifting and transporting anesthetized pigs weighing up to 350 kg using...... mechanical lifts. Different equipment was used to accommodate pigs of different sizes as well as the building designs of three animal facilities. Using the lifts, anesthetized pigs are carried on sheets to maintain their comfort while being transported. The approach refines previous methods for handling...

  16. Interaction of local anesthetics with a peptide encompassing the IV/S4-S5 linker of the Na+ channel.

    Science.gov (United States)

    Fraceto, Leonardo F; Oyama, Sérgio; Nakaie, Clóvis R; Spisni, Alberto; de Paula, Eneida; Pertinhez, Thelma A

    2006-08-20

    The peptide pIV/S4-S5 encompasses the cytoplasmic linker between helices S4-S5 in domain IV of the voltage-gated Na+ channel, residues 1644-1664. The interaction of two local anesthetics (LA), lidocaine and benzocaine, with pIV/S4-S5 has been studied by DOSY, heteronuclear NMR 1H-15N-HSQC spectroscopy and computational methods. DOSY indicates that benzocaine, a neutral ester, exhibits stronger interaction with pIV/S4-S5 than lidocaine, a charged amine-amide. Weighted average chemical shifts, Deltadelta(1H-15N), show that benzocaine affects residues L1653, M1655 and S1656 while lidocaine slightly perturbs residues I1646, L1649 and A1659, L1660, near the N- and C-terminus, respectively. Computational methods confirmed the stability of the benzocaine binding and the existence of two binding sites for lidocaine. Even considering that the approach of studying the peptide in the presence of a co-solvent (TFE/H2O, 30%/70% v/v) has an inherently limited implication, our data strongly support the existence of multiple LA binding sites in the IV/S4-S5 linker, as suggested in the literature. In addition, we consider that LA can bind to the S4-S5 linker with diverse binding modes and strength since this linker is part of the receptor for the "inactivation gate particle". Conditions for devising new functional studies, aiming to better understand Na+ channel functionality as well as the various facets of LA pharmacological activity are proposed in this work.

  17. Sorption of volatile phenols by yeast cell walls

    Directory of Open Access Journals (Sweden)

    Nerea Jiménez-Moreno

    2009-01-01

    Full Text Available Nerea Jiménez-Moreno, Carmen Ancín-AzpilicuetaDepartment of Applied Chemistry, Universidad Pública de Navarra, Pamplona, SpainAbstract: Yeast walls can retain different wine compounds and so its use is interesting in order to eliminate harmful substances from the must which affect alcoholic fermentation (medium chain fatty acids or which affect wine quality in a negative way (ethyl phenols, ochratoxin A. The aim of this study was to examine the capacity of commercial yeast cell walls in eliminating volatile phenols (4-ethylphenol and 4-ethylguaiacol from a synthetic wine that contained 1 mg/L of each one of these compounds. The binding of these compounds to the wall was quite fast which would seem to indicate that the yeast wall-volatile compound union is produced in the outer surface layers of this enological additive. The cell walls used reduced the concentration of 4-ethylphenol and 4-ethylguaiacol, although it would seem that on modifying the matrix of the wine the number of free binding sites on the walls is also modified.Keywords: volatile phenols, yeast cell walls, wine, sorption

  18. DOES ENERGY CONSUMPTION VOLATILITY AFFECT REAL GDP VOLATILITY? AN EMPIRICAL ANALYSIS FOR THE UK

    Directory of Open Access Journals (Sweden)

    Abdul Rashid

    2013-10-01

    Full Text Available This paper empirically examines the relation between energy consumption volatility and unpredictable variations in real gross domestic product (GDP in the UK. Estimating the Markov switching ARCH model we find a significant regime switching in the behavior of both energy consumption and GDP volatility. The results from the Markov regime-switching model show that the variability of energy consumption has a significant role to play in determining the behavior of GDP volatilities. Moreover, the results suggest that the impacts of unpredictable variations in energy consumption on GDP volatility are asymmetric, depending on the intensity of volatility. In particular, we find that while there is no significant contemporaneous relationship between energy consumption volatility and GDP volatility in the first (low-volatility regime, GDP volatility is significantly positively related to the volatility of energy utilization in the second (high-volatility regime.

  19. [Pediatric anesthetic during brain immaturity and neurodevelopment disorders].

    Science.gov (United States)

    Catré, Dora; Lopes, Maria Francelina; Cabrita, António Silvério; Silva Viana, Joaquim

    2014-01-01

    Introdução: Diversos estudos experimentais e clínicos sugerem que fármacos usados em anestesia pediátrica podem exercer efeitos indesejáveis sobre o sistema nervoso central imaturo. O objetivo desta revisão consistiu em avaliar os resultados e conclusões de estudos publicados na literatura sobre perturbações persistentes do neurodesenvolvimento após exposição a anestésicos de crianças em fase de imaturidade cerebral. Material e Métodos: Realizámos uma pesquisa bibliográfica em diversas bases de dados (PubMed, SciELO e Cochrane Library), utilizando os termos ‘Pediatric anesthesia OR Pediatric anesthetic OR Developing brain anesthetic OR Developing brain anesthesia AND behavior disorders’ e foram incluídos os estudos em humanos, referentes a efeitos persistentes no neurodesenvolvimento após exposição a anestésicos nos primeiros quatro anos de idade. Resultados: Dez estudos retrospetivos cumpriram os critérios de inclusão. Destes, sete sugerem alteração do neurodesenvolvimento por exposição de criança pequena à anestesia, por oposição aos resultados obtidos pelos restantes três. Discussão: Embora maioritariamente utilizem bases de dados amplas, os estudos encontrados são retrospetivos, variam nos grupos teste, incluem variáveis de confusão por vezes contornáveis e alguns apresentam incorreções na escolha da população teste e controlo que podem comprometer a fiabilidade dos resultados. Conclusão: As numerosas limitações dos poucos estudos clínicos disponíveis fazem com que a informação reportada ainda se considere insuficiente para mudar a prática clínica atual. No entanto, sendo indiscutível que se mantêm as recomendações para providenciar anestesia quando necessária, independentemente da idade, os alertas encontrados na literatura são preocupantes, existindo indicação para que sempre que possível sejam ponderadas alternativas que possam contribuir para diminuir os riscos da exposição anestésica.

  20. Factors affecting the volatilization of volatile organic compounds from wastewater

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    Junya Intamanee

    2006-09-01

    Full Text Available This study aimed to understand the influence of the wind speed (U10cm, water depth (h and suspended solids (SS on mass transfer coefficient (KOLa of volatile organic compounds (VOCs volatilized from wastewater. The novelty of this work is not the method used to determine KOLa but rather the use of actual wastewater instead of pure water as previously reported. The influence of U10cm, h, and SS on KOLa was performed using a volatilization tank with the volume of 100-350 L. Methyl Ethyl Ketone (MEK was selected as a representative of VOCs investigated here in. The results revealed that the relationship between KOLa and the wind speeds falls into two regimes with a break at the wind speed of 2.4 m/s. At U10cm 2.4 m/s, KOLa increased more rapidly. The relationship between KOLa and U10cm was also linear but has a distinctly higher slope. For the KOLa dependency on water depth, the KOLa decreased significantly with increasing water depth up to a certain water depth after that the increase in water depth had small effect on KOLa. The suspended solids in wastewater also played an important role on KOLa. Increased SS resulted in a significant reduction of KOLa over the investigated range of SS. Finally, the comparison between KOLa obtained from wastewater and that of pure water revealed that KOLa from wastewater were much lower than that of pure water which was pronounced at high wind speed and at small water depth. This was due the presence of organic mass in wastewater which provided a barrier to mass transfer and reduced the degree of turbulence in the water body resulting in low volatilization rate and thus KOLa. From these results, the mass transfer model for predicting VOCs emission from wastewater should be developed based on the volatilization of VOCs from wastewater rather than that from pure water.

  1. Fluctuation behaviors of financial return volatility duration

    Science.gov (United States)

    Niu, Hongli; Wang, Jun; Lu, Yunfan

    2016-04-01

    It is of significantly crucial to understand the return volatility of financial markets because it helps to quantify the investment risk, optimize the portfolio, and provide a key input of option pricing models. The characteristics of isolated high volatility events above certain threshold in price fluctuations and the distributions of return intervals between these events arouse great interest in financial research. In the present work, we introduce a new concept of daily return volatility duration, which is defined as the shortest passage time when the future volatility intensity is above or below the current volatility intensity (without predefining a threshold). The statistical properties of the daily return volatility durations for seven representative stock indices from the world financial markets are investigated. Some useful and interesting empirical results of these volatility duration series about the probability distributions, memory effects and multifractal properties are obtained. These results also show that the proposed stock volatility series analysis is a meaningful and beneficial trial.

  2. Modeling the Volatility in Global Fertilizer Prices

    NARCIS (Netherlands)

    P-Y. Chen (Ping-Yu); C-L. Chang (Chia-Lin); C-C. Chen (Chi-Chung); M.J. McAleer (Michael)

    2010-01-01

    textabstractThe main purpose of this paper is to estimate the volatility in global fertilizer prices. The endogenous structural breakpoint unit root test and alternative volatility models, including the generalized autoregressive conditional heteroskedasticity (GARCH) model, Exponential GARCH (EGARC

  3. Stochastic Volatility and DSGE Models

    DEFF Research Database (Denmark)

    Andreasen, Martin Møller

    This paper argues that a specification of stochastic volatility commonly used to analyze the Great Moderation in DSGE models may not be appropriate, because the level of a process with this specification does not have conditional or unconditional moments. This is unfortunate because agents may...

  4. The Effects of Anesthetic Technique on Postoperative Opioid Consumption in Ankle Fracture Surgery

    DEFF Research Database (Denmark)

    Christensen, Kristian P; Møller, Ann M; Nielsen, Jesper Kjær;

    2015-01-01

    OBJECTIVES: To investigate the impact of common anesthetic techniques on postoperative opioid consumption in ankle fracture surgery. MATERIALS AND METHODS: We performed a retrospective cohort study on 622 patients with isolated ankle fractures undergoing primary reconstructive surgery. Patients...

  5. Trigeminal nerve injury associated with injection of local anesthetics: needle lesion or neurotoxicity?

    DEFF Research Database (Denmark)

    Hillerup, Søren; Jensen, Rigmor H; Ersbøll, Bjarne Kjær

    2011-01-01

    The authors used comprehensive national registry and clinical data to conduct a study of adverse drug reactions (ADRs), in particular neurosensory disturbance (NSD), associated with local anesthetics used in dentistry...

  6. Anesthetic implications for video assisted thoracoscopic thymectomy in myasthenia gravis.

    Science.gov (United States)

    El-Dawlatly, Abdelazeem A; Al Kattan, Khaled; Hajjar, Waseem; Essa, Mohamed; Delvi, Bilal; Khoja, Abdulaziz

    2005-06-01

    Thymectomy is an established therapy in the management of generalized myasthenia gravis (MG). However, the optimal surgical approach to thymectomy has remained controversial. There are advocates for transternal, transcervical approaches for "maximal" thymectomy. Video-assisted thoracoscopic thymectomy (VATT) presents new approach to thymectomy. By minimizing chest wall trauma, VATT not only causes less postoperative pain, shortens hospital stay, gives better cosmetic results but also leads to wider acceptance by patients for earlier surgery. Anesthesia for thymectomy in MG is challenging. Currently we are using non-muscle relaxant technique (NMRT) which we adopted in 1994, for maximal thymectomy. In this paper, we present our limited experience with two cases of VATT using two different NMRTs. Two cases of MG underwent VATT under general anesthesia (GA) and one lung ventilation (OLV) using double lumen tube (DLT). In both cases NMRT was used which encompass, light GA plus thoracic epidural analgesia (TEA) in one case and without TEA in the other case. We believe that the use of NMRT provides good operative and postoperative conditions. In this report we have described two different NMRTs, one with TEA and the other without. Further studies are needed on large number of cases to establish an anesthetic protocol for VATT.

  7. Urotensin Ⅱ inhibits carotid sinus baroreflex in anesthetized male rats

    Institute of Scientific and Technical Information of China (English)

    Yu-ming WU; Hong-mei XUE; Lin XIAO; Rui-rong HE

    2007-01-01

    Aim: To study the effects of urotensin Ⅱ (UV) on the carotid sinus baroreflex (CSB). Methods: The functional curve of carotid sinus baroreflex was measured by recording changes in arterial pressure in anesthetized male rats with perfused isolated carotid sinus. Results: UⅡ at the concentration of 3 nmol/L had no effect on the CSB, while at the concentration of 30, 300 and 3000 nmol/L inhibited the CSB, shifting the functional curve of the baroreflex upward and to the right. There was a marked decrease in peak slope and reflex decrease in blood pressure. These effects of UⅡ were concentration-dependent. Pretreatment with verapamil (an antagonist of the L-type calcium channel, 10 μmol/L) partially eliminated the above effects of UⅡ (300 nmol/L) on the CSB. Pretreatment with BIM-23127 (3 μmol/L),an antagonist of human and rat UⅡ receptors, abolished the actions of UⅡ on the CSB. Pretreatment with, NG-nitro-L-arginine methyl ester (L-NAME) 100 μmol/L did not affect the inhibitory effects of UⅡ (300 nmol/L) on the CSB. Conclusion: These data suggest that UⅡ exerts an inhibitory action on the isolated CSB. Such an action of UV is predominantly mediated by the UⅡ receptors in vascular smooth muscles, resulting in the opening of L-type calcium channels.

  8. Congenital lobar emphysema: A modified approach to anesthetic management

    Directory of Open Access Journals (Sweden)

    Malathi C Nandihalli

    2015-01-01

    Full Text Available Congenital lobar emphysema (CLE is a potentially reversible, though life-threatening cause of respiratory distress in neonates. It is a rare developmental anomaly of the lower respiratory tract. A 10-month-old child presented with fever, cough and difficulty in breathing. Respiratory system examination revealed tachypnea with intercostal retraction, decreased breath sounds over the left upper lobe and room air saturation of 95%. Chest radiograph and computed tomography showed hyperinflated left upper zones with mediastinal shift. Left thoracotomy, followed by left upper lobectomy was performed under general anesthesia with one lung ventilation. Oxygen saturation, blood pressure, electrocardiogram and capnogram were continuously monitored. During anesthesia, conventionally positive pressure ventilation is avoided until the diseased lobe is isolated, however we adopted gentle manual ventilation maintaining the airway pressure before thoracotomy as described by Cotι and Payne et al. Successful anesthetic management of CLE can be achieved by proper understanding of pathophysiology, good perioperative monitoring, and adopting novel management strategies.

  9. A Comparison of Intramuscular Anesthetic Techniques in Chickens

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    Shahin Hajighahramani

    2017-02-01

    Full Text Available Background & Objective: Administration of anesthetic substances to chickens requires careful consideration for the safe delivery of the agent to the bird. The research objective was to evaluate several drug combinations for intramuscular anesthesia in chickens for physiologic, nutritional, pharmacological and other investigations. Meterial & Methods: Sixty healthy chickens were randomly assigned in six treatment groups and received Ketamine in combination with Xylazine, Midazolam or Acepromazine. Heart and respiratory rate, induction time, duration of surgical anesthesia and light anesthesia were measured. Results: Induction of anesthesia was significantly longer following Acepromazine- Ketamine and Midazolam- Ketamine compared to other groups (P<0.05. Duration of surgical anesthesia was longest with Xylazine- Midazolam- Ketamine and shortest with Midazolam-Ketamine and Acepromazine- Ketamine (P<0.05. Conclusion: In conclusion, the most effective drug combinations resulting in longer duration of surgical anesthesia, were Xylazine- Acepromazine- Ketamine and Xylazine- Midazolam- Ketamine. Other combinations did not produce appropriate surgical anesthesia, but they make slight changes in physiological data.

  10. Anesthetic and surgical complications in 219 cases of myotonic dystrophy.

    Science.gov (United States)

    Mathieu, J; Allard, P; Gobeil, G; Girard, M; De Braekeleer, M; Bégin, P

    1997-12-01

    The objective of this study was to assess the frequency, type, and severity of perioperative complications after a first surgery under general anesthesia in patients with myotonic dystrophy (DM) and to measure the association with suspected risk factors. Numerous cases of perioperative complications in DM patients have been reported. Hazards have been associated with the use of thiopentone, suxamethonium, neostigmine, and halothane. A retrospective study of perioperative complications was conducted for 219 DM patients who had their first surgery under general anesthesia at the Chicoutimi Hospital. The overall frequency of complications was 8.2% (18 of 219). Most complications (16 of 18) were pulmonary, including five patients with acute ventilatory failure necessitating ventilatory support, four patients with atelectasis, and three patients with pneumonia. Using multivariate analysis, we found that the risk of perioperative pulmonary complications (PPC) was significantly higher after an upper abdominal surgery (odds ratio (OR), 24.4; 95% CI, 4.0 to 149.3) and for patients with a severe muscular disability, as assessed by the presence of proximal limb weakness (OR, 14.1; 95% CI, 1.5 to 134.4). The likelihood of PPC was not related to any specific anesthetic drug. Because of the increased risk of PPC, careful monitoring during the early postoperative period, protection of upper airways, chest physiotherapy, and incentive spirometry are mandatory in all symptomatic DM patients, particularly those with a severe muscular disability or those who have undergone an upper abdominal surgery.

  11. Anesthetic Management of a Pediatric Patient With Wilsons Disease

    Science.gov (United States)

    Baykal, Mehmet; Karapolat, Sami

    2010-01-01

    Wilsons disease, characterized by cirrhosis, extrapyramidal symptoms and Kayser-Fleischer corneal rings, is a rare hereditary disease of human copper metabolism. Clinical findings in Wilsons disease are complex and neurological symptoms such as tremor, dysarthria, rigid dystonia, seizures, psychiatric disorders, acute liver failure, chronic hepatitis or cirrhosis may develop. A 4-year-old male patient was operated for traumatic depressed skull fracture and intracerebral hematoma. He was diagnosed with Wilsons disease at the age of 2.5 years and treated with zinc sulphate and D-penicillamine. General anesthesia was induced with propofol, fentanyl, atracurium, and maintained with isoflurane, and oxygen. No complications were encountered during the operation or in the postoperative period. We concluded that general anesthesia can successfully be given to Wilsons disease patients using an anesthetic agent, the metabolism of which is least affected by the liver disease, one that induces least hepatic toxicity. By close follow-up of patients clinically and biochemically, it is possible to reduce the complication rates to a minimum. Keywords Wilson's Disease; Craniocerebral trauma; Thoracic injuries; General anesthesia; Surgery PMID:21811529

  12. Anesthetic Management of a Pediatric Patient with Arginase Deficiency

    Directory of Open Access Journals (Sweden)

    Abdulkadir Atım

    2011-09-01

    Full Text Available Arginase deficiency is an autosomal recessive disorder of the urea cycle in which a defect in conversion of arginine to urea and ornithine leads to hyperammonemia. Patients with urea cycle disorders may show increased protein catabolism due to inadequate intake of energy, protein and essential amino acids; infections, fever and surgery. A 12-year-old girl with arginase deficiency, ASA II who weighed 40 kg was scheduled for bilateral adductor, quadriceps and gastrocnemius tenotomies. She had mental retardation, spasticity and flexion posture of thelower limbs. Metabolic homeostasis was restored with appropriate diet. Successful anesthetic management allowed the patient to be discharged 48 hours after surgery. Increased levels of arginine and ammonia during or after surgery may lead to serious complications such as hypotension, cerebral edema, convulsions, hypothermia and spasticity. Thus special attention must be given to metabolic homeostasis and nutrition of the patients with arginase deficiency in the perioperative period. Primary goals should be to minimize stress levels by effective anxiolysis, provide an adequate amount of protein-free energy with proper fluid management and to obtain an effective preemptive and postoperative analgesia. In addition to a high level of knowledge, successful anesthesia requires professional communication among nursing staff, dietitians, pediatric metabolism specialist, surgeon and anesthesiologist.

  13. Extended duration local anesthetic agent in a rat paw model.

    Science.gov (United States)

    Ickowicz, D E; Golovanevski, L; Domb, A J; Weiniger, C F

    2014-07-01

    Encapsulated local anesthetics extend postoperative analgesic effect following site-directed nerve injection; potentially reducing postoperative complications. Our study aim was to investigate efficacy of our improved extended duration formulation - 15% bupivacaine in poly(DL-lactic acid co castor oil) 3:7 synthesized by ring opening polymerization. In vitro, around 70% of bupivacaine was released from the p(DLLA-CO) 3:7 after 10 days. A single injection of the optimal formulation of 15% bupivacaine-polymer or plain (0.5%) bupivacaine (control), was injected via a 22G needle beside the sciatic nerve of Sprague-Dawley rats under anesthesia; followed (in some animals) by a 1cm longitudinal incision through the skin and fascia of the paw area. Behavioral tests for sensory and motor block assessment were done using Hargreave's hot plate score, von Frey filaments and rearing count. The 15% bupivacaine formulation significantly prolonged sensory block duration up to at least 48 h. Following surgery, motor block was observed for 48 h following administration of bupivacaine-polymer formulation and rearing was reduced (returning to baseline after 48 h). No significant differences in mechanical nociceptive response were observed. The optimized bupivacaine-polymer formulation prolonged duration of local anesthesia effect in our animal model up to at least 48 h.

  14. Severe preeclampsia: anesthetic implications of the disease and its management.

    Science.gov (United States)

    Turner, Judi A

    2009-01-01

    Preeclampsia is a significant, multifactorial, multiorgan disease affecting 6%-8% of all pregnancies in the United States and is the third leading cause of maternal mortality. As such, it is incumbent upon any anesthesia provider involved in obstetric cases to be familiar with the varied manifestations of the disease, management goals from an obstetric standpoint, and the implications for provision of anesthesia in this patient group. Despite improvements in the diagnosis and management of preeclampsia, severe complications can occur in both the mother and the fetus. A systematic approach to the anesthetic evaluation is therefore necessary to reduce morbidity and mortality and to improve outcomes. The potential pitfalls of general anesthesia, including failed intubation, in these complicated patients make regional anesthesia the preferred choice in many cases. Recent studies have shown that spinal anesthesia is often appropriate for preeclamptic patients, even in severe cases. Nevertheless, it is important to be aware of the potential contraindications to neuraxial anesthesia and to prepare for the possibility of encountering a difficult airway.

  15. The articulo-cardiac sympathetic reflex in spinalized, anesthetized rats.

    Science.gov (United States)

    Nakayama, Tomohiro; Suzuki, Atsuko; Ito, Ryuzo

    2006-04-01

    Somatic afferent regulation of heart rate by noxious knee joint stimulation has been proven in anesthetized cats to be a reflex response whose reflex center is in the brain and whose efferent arc is a cardiac sympathetic nerve. In the present study we examined whether articular stimulation could influence heart rate by this efferent sympathetic pathway in spinalized rats. In central nervous system (CNS)-intact rats, noxious articular movement of either the knee or elbow joint resulted in an increase in cardiac sympathetic nerve activity and heart rate. However, although in acutely spinalized rats a noxious movement of the elbow joint resulted in a significant increase in cardiac sympathetic nerve activity and heart rate, a noxious movement of the knee joint had no such effect and resulted in only a marginal increase in heart rate. Because this marginal increase was abolished by adrenalectomy suggests that it was due to the release of adrenal catecholamines. In conclusion, the spinal cord appears to be capable of mediating, by way of cardiac sympathetic nerves, the propriospinally induced reflex increase in heart rate that follows noxious stimulation of the elbow joint, but not the knee joint.

  16. “Robo-Tripping”: Dextromethorphan Abuse and its Anesthetic Implications

    Science.gov (United States)

    Linn, Kelly A; Long, Micah T; Pagel, Paul S

    2014-01-01

    Introduction: We describe a patient scheduled for elective surgery who regularly consumed approximately 12 to 15 times the maximum recommended daily dose of dextromethorphan. We describe the clinical pharmacology of dextromethorphan and discuss its anesthetic implications. Case Presentation: A 30-year-old man with a history of a nasal fracture was scheduled to undergo an elective septorhinoplasty. He reported daily consumption of large quantities (1440 to 1800 mg) of dextromethorphan for six years. He was previously treated for dextromethorphan dependency on several occasions with urine dextromethorphan levels exceeding 2000 ng/mL. He described marked dissociative effects when abusing the drug, but had abstained from use for 48 hours before his elective surgery. Considering that dextromethorphan has a relatively short half-life and that the patient did not suffer major withdrawal symptoms after voluntarily discontinuing the drug, the authors proceeded with the case while recognizing that the drug has significant neuropsychiatric and sympathetic nervous system stimulant effects resulting from its actions as a N-methyl-D-aspartate receptor antagonist. Conclusions: Anesthesiologists need to be aware of dextromethorphan’s clinical pharmacology because recreational abuse of the drug has become increasingly common in adolescents and young adults. PMID:25793175

  17. Anesthetic management of a patient with multiple sclerosis - case report

    Directory of Open Access Journals (Sweden)

    Eduardo Barbin Zuccolotto

    Full Text Available Abstract Background and objectives: Multiple sclerosis is a demyelinating disease of the brain and spinal cord, characterized by muscle weakness, cognitive dysfunction, memory loss, and personality disorders. Factors that promote disease exacerbation are stress, physical trauma, infection, surgery, and hyperthermia. The objective is to describe the anesthetic management of a case referred to urological surgery. Case report: A female patient, 44 years of age, with multiple sclerosis, diagnosed with nephrolithiasis, referred for endoscopic ureterolythotripsy. Balanced general anesthesia was chosen, with midazolam, propofol and remifentanil target-controlled infusion; sevoflurane via laryngeal mask airway; and spontaneous ventilation. Because the patient had respiratory difficulty presenting with chest wall rigidity, it was decided to discontinue the infusion of remifentanil. There was no other complication or exacerbation of disease postoperatively. Conclusion: The use of neuromuscular blockers (depolarizing and non-depolarizing is a problem in these patients. As there was no need for muscle relaxation in this case, muscle relaxants were omitted. We conclude that the combination of propofol and sevoflurane was satisfactory, not resulting in hemodynamic instability or disease exacerbation.

  18. Hydrogen sulfide facilitates carotid sinus baroreflex in anesthetized rats

    Institute of Scientific and Technical Information of China (English)

    Lin XIAO; Yu-ming WU; Hao ZHANG; Yi-xian LIU; Rui-rong HE

    2006-01-01

    Aim:To study effects of hydrogen sulfide (H2S)on the carotid sinus baroreflex (CSB).Methods:The functional curve of the carotid sinus baroreflex was measured by recording changes in arterial pressure in anesthetized male rats with perfused carotid sinus.Results:H2S(derived from sodium hydrosulfide)at concentrations of 25,50,and 100 μmol/L facilitated the CSB,shifting the functional curve of the baroreflex downward and to the left.There was a marked increase in peak slope(PS)and reflex decrease in blood pressure(RD).Effects were concentration-dependent.Pretreatment with glibenclamide(20 μmol/L),a KATP channel blocker,abolished the above effects of H2S on CSB.Pretreatment with Bay K8644 (an agonist of calcium channels;500 nmol/L)eliminated the effect of H2S on CSB.An inhibitor of cystathionine γ-lyase(CSE),DL-propargylglycine(PPG;200 μmol/L),inhibited CSB in male rats and shifted the functional curve of the baroreflex upward and to the right.Conclusion:These data suggest that exogenous H2S exerts a facilitatory role on isolated CSB through opening KATP channels and further closing the calcium channels in vascular smooth muscle.Endogenous H2S may activate the activity of the CSB in vivo.

  19. Anterior and posterior tibial anesthetic block in diabetic foot surgery.

    Directory of Open Access Journals (Sweden)

    José Julio Ojeda González

    2004-12-01

    Full Text Available Fundament: Diabetes Mellitus is a disease of high and increasing prevalence and its complications follow a parallel course. Its morbidity is derived from its own complications which are produced at a long or short term and peripheral vascular disease hihglights among them.Objective: to check the usefulness of the anterior and posterior blockade of the tibia for the surgery of the diabetic foot. Method: Prospective study carried out from January to December 2003 at the University Hospital ¨Dr. Gustavo Aldereguía Lima¨ to patients who are carriers of a diabetic foot and who were initially assisted at the service of Angiology and later at the service of Anesthesiology when the surgical procedures were decided. All the patients were applied an anterior and posterior blockade of the tibial nerve . The variables measured were: age, weight, height, surgical time, type of surgery, cardiac frequency medium arterial pressure, and classification of patients according to the American Association of Anesthesiology All the patients were applied a scale for assessing pain in three different moments.Result: There was a predominance of females . The blockade of the posterior tibial nerve with lidocaine 1 % in different points permitted the performance of the surgical techniques proposed. The anesthetic procedure was favorable, and economic since the patients did not requiere of the use of analgesic in the post operatory stage.

  20. Anesthesia methods used by anesthetic specialists for circumcision cases

    Science.gov (United States)

    Altaş, Cafer; Küçükosman, Gamze; Yurtlu, Bülent S.; Okyay, Rahşan D.; Aydın, Bengü G.; Pişkin, Özcan; Çimencan, Murat; Ayoğlu, Hilal; Hancı, Volkan; Özkoçak-Turan, Işıl

    2017-01-01

    Objectives: To examine the anesthesiologist’s choice for anesthesia techniques and drugs in circumcision and determine the preoperative examination, intraoperative monitoring techniques, postoperative analgesia methods, and common complications among anesthesiologists working in Turkey. Methods: This cross-sectional study was conducted at Bulent Ecevit University Hospital, Zonguldak, Turkey, between May and July 2012. Survey data were obtained via survey forms through electronic data over the web. The questionnaire consists of 20 questions. These questions included demographic data, methods of anesthesia for circumcision, postoperative analgesia methods, and monitoring methods. Results: The data were obtained from 206 anesthesiologists who agreed to participate in the survey. Circumcision was performed most frequently in the age group of 3-6 years old. It was found that 47% of routine preoperative laboratory tests were coagulation parameters and complete blood count tests. The most common method of anesthesia was laryngeal mask. The frequency of administration of regional anesthesia was 37.4%, and caudal block was more preferable. Bupivacaine as a local anesthetic in regional anesthesia and midazolam and ketamine were the most preferred agents in sedoanalgesia. During regional anesthesia, ultrasound was most often used by anesthesiologists (31.6%). Conclusion: Ambulatory anesthesia protocols, which are also needed in circumcision, can be improved with international recommendation, and these protocols could be conformed as sociocultural structure in societies. This study should be regarded as a preliminary study to attract attention on anesthesia techniques in circumcision. PMID:28042634

  1. Abdominal expiratory muscle activity in anesthetized vagotomized neonatal rats.

    Science.gov (United States)

    Iizuka, Makito

    2009-05-01

    The pattern of respiratory activity in abdominal muscles was studied in anesthetized, spontaneously breathing, vagotomized neonatal rats at postnatal days 0-3. Anesthesia (2.0% isoflurane, 50% O(2)) depressed breathing and resulted in hypercapnia. Under this condition, abdominal muscles showed discharge late in the expiratory phase (E2 activity) in most rats. As the depth of anesthesia decreased, the amplitude of discharges in the diaphragm and abdominal muscles increased. A small additional burst frequently occurred in abdominal muscles just after the termination of diaphragmatic inspiratory activity (E1 or postinspiratory activity). Since this E1 activity is not often observed in adult rats, the abdominal respiratory pattern likely changes during postnatal development. Anoxia-induced gasping after periodic expiratory activity without inspiratory activity, and in most rats, abdominal expiratory activity disappeared before terminal apnea. These results suggest that a biphasic abdominal motor pattern (a combination of E2 and E1 activity) is a characteristic of vagotomized neonatal rats during normal respiration.

  2. Neonatal inhalatory anesthetic exposure: reproductive changes in male rats.

    Science.gov (United States)

    Arena, A C; Pereira, O C M

    2002-12-01

    We investigated the effects of an inhalatory anesthetic (ethyl ether) during the neonatal period of brain sexual differentiation on the later fertility and sexual behavior of male rats. Animals were exposed to ethyl ether immediately after birth. At adulthood, body weight, testes wet weight, and plasma testosterone levels were not affected; however, neonatal exposure to ether showed alterations on male fertility: a decrease in the number of spermatids and spermatozoa, an increase in the transit time of cauda epididymal spermatozoa and a decrease in daily sperm production. An alteration of sexual behavior was also observed: decreased male sexual behavior and appearance of homosexual behavior when the male rats were castrated and pretreated with exogenous estrogen. Probably, the ether delayed or reduced the testosterone peak of the sexual differentiation period, altering the processes of masculinization and defeminization of the hypothalamus. Our results indicate that perinatal exposure to ethyl ether during the critical period of male brain sexual differentiation, acting as endocrine disruptors, has a long-term effect on the fertility and sexual behavior of male rats, suggesting endocrine disruption through incomplete masculinization and defeminization of the central nervous system.

  3. Possible Sources of Polar Volatiles

    Science.gov (United States)

    Schultz, P. H.

    2011-12-01

    Extensive analyses of returned Apollo samples demonstrated that the Moon is extremely volatile poor. While this conclusion remains true, various measurements since the late 90's implicated the presence of water: e.g., enhanced reflection of circularly polarized radar signals and suppression of epithermal neutrons near the poles. More recently, traces of H2O have been discovered inside volcanic glass, along with more significant amounts residing in hydrous minerals (apatite) returned from both highland and mare landing sites. Three recent lunar missions (DIXI, M3, Cassini) identified hydrous phases on/near the lunar surface, whereas the LCROSS probe detected significant quantities of volatiles (OH, H2O and other volatiles) excavated by the Centaur impact. These new mission results and sample studies, however, now allow testing different hypotheses for the generation, trapping, and replenishment of these volatiles. Solar-proton implantation must contribute to the hydrous phases in the lunar regolith in order to account for the observed time-varying abundances and occurrence near the lunar equator. This also cannot be the entire story. The relatively low speed LCROSS-Centaur impact (2.5km/s) could not vaporize such hydrous minerals, yet emissions lines of OH (from the thermal disassociation of H2O), along with other compounds (CO2, NH2) were detected within the first second, before ejecta could reach sunlight. Telescopic observations by Potter and Morgan (1985) discovered a tenuous lunar atmosphere of Na, but the LCROSS UV/Vis spectrometer did not detect the Na-D line until after the ejecta reached sunlight (along with a line pair attributed to Ag). With time, other volatile species emerged (OH, CO). The LAMP instrument on the Lunar Reconnaissance Orbiter had a different viewpoint from the side (rather than from above) and detected many other atomic species release by the LCROSS-Centaur impact. Consequently, it appears that there is a stratigraphy for trapped species

  4. Cimethidine pre-anesthetic. A prophylactic method against Mendelson's syndrome in cesarean section

    DEFF Research Database (Denmark)

    Qvist, N; Storm, K

    1983-01-01

    Twenty patients undergoing cesarean section received cimethidine 400 mg intramuscularly as pre-anesthetic approximately 70 minutes prior to gastric aspiration. The average pH was 5.05, as against 2.97 in the control group (p less than 0.01). No significant reduction in the aspirated volumes...... in the infants. Hence, cimethidine is a safe and useful pre-anesthetic for patients undergoing cesarean section, irrespective of indication and, consequently, much to be preferred to oral antacids....

  5. Precautionary practices for administering anesthetic gases: A survey of physician anesthesiologists, nurse anesthetists and anesthesiologist assistants.

    Science.gov (United States)

    Boiano, James M; Steege, Andrea L

    2016-10-02

    Scavenging systems and administrative and work practice controls for minimizing occupational exposure to waste anesthetic gases have been recommended for many years. Anesthetic gases and vapors that are released or leak out during medical procedures are considered waste anesthetic gases. To better understand the extent recommended practices are used, the NIOSH Health and Safety Practices Survey of Healthcare Workers was conducted in 2011 among members of professional practice organizations representing anesthesia care providers including physician anesthesiologists, nurse anesthetists, and anesthesiologist assistants. This national survey is the first to examine self-reported use of controls to minimize exposure to waste anesthetic gases among anesthesia care providers. The survey was completed by 1,783 nurse anesthetists, 1,104 physician anesthesiologists, and 100 anesthesiologist assistants who administered inhaled anesthetics in the seven days prior to the survey. Working in hospitals and outpatient surgical centers, respondents most often administered sevoflurane and, to a lesser extent desflurane and isoflurane, in combination with nitrous oxide. Use of scavenging systems was nearly universal, reported by 97% of respondents. However, adherence to other recommended practices was lacking to varying degrees and differed among those administering anesthetics to pediatric (P) or adult (A) patients. Examples of practices which increase exposure risk, expressed as percent of respondents, included: using high (fresh gas) flow anesthesia only (17% P, 6% A), starting anesthetic gas flow before delivery mask or airway mask was applied to patient (35% P; 14% A); not routinely checking anesthesia equipment for leaks (4% P, 5% A), and using a funnel-fill system to fill vaporizers (16%). Respondents also reported that facilities lacked safe handling procedures (19%) and hazard awareness training (18%). Adherence to precautionary work practices was generally highest among

  6. Latency of auditory evoked potential monitoring the effects of general anesthetics on nerve fibers and synapses

    OpenAIRE

    Bowan Huang; Feixue Liang; Lei Zhong; Minlin Lin; Juan Yang; Linqing Yan; Jinfan Xiao; Zhongju Xiao

    2015-01-01

    Auditory evoked potential (AEP) is an effective index for the effects of general anesthetics. However, it’s unknown if AEP can differentiate the effects of general anesthetics on nerve fibers and synapses. Presently, we investigated AEP latency and amplitude changes to different acoustic intensities during pentobarbital anesthesia. Latency more regularly changed than amplitude during anesthesia. AEP Latency monotonically decreased with acoustic intensity increase (i.e., latency-intensity curv...

  7. Wound infiltration with local anesthetics for post-operative pain relief in lumbar spine surgery

    DEFF Research Database (Denmark)

    Kjærgaard, M; Møiniche, S; Olsen, K S

    2012-01-01

    In this systematic review, we evaluated double-blind, randomized and controlled trials on the effect of wound infiltration with local anesthetics compared with the effect of placebo on post-operative pain after lumbar spine surgery.......In this systematic review, we evaluated double-blind, randomized and controlled trials on the effect of wound infiltration with local anesthetics compared with the effect of placebo on post-operative pain after lumbar spine surgery....

  8. Anesthetic Sevoflurane Causes Rho-Dependent Filopodial Shortening in Mouse Neurons.

    Directory of Open Access Journals (Sweden)

    Jeffrey H Zimering

    Full Text Available Early postnatal anesthesia causes long-lasting learning and memory impairment in rodents, however, evidence for a specific neurotoxic effect on early synaptogenesis has not been demonstrated. Drebrin A is an actin binding protein whose localization in dendritic protrusions serves an important role in dendritic spine morphogenesis, and is a marker for early synaptogenesis. We therefore set out to investigate whether clinically-relevant concentrations of anesthetic sevoflurane, widely- used in infants and children, alters dendritic morphology in cultured fetal day 16 mouse hippocampal neurons. After 7 days in vitro, mouse hippocampal neurons were exposed to four hours of 3% sevoflurane in 95% air/5% CO2 or control condition (95% air/5% CO2. Neurons were fixed in 4% paraformaldehyde and stained with Alexa Fluor555-Phalloidin, and/or rabbit anti-mouse drebrin A/E antibodies which permitted subcellular localization of filamentous (F-actin and/or drebrin immunoreactivity, respectively. Sevoflurane caused acute significant length-shortening in filopodia and thin dendritic spines in days-in-vitro 7 neurons, an effect which was completely rescued by co-incubating neurons with ten micromolar concentrations of the selective Rho kinase inhibitor Y27632. Filopodia and thin spine recovered in length two days after sevoflurane exposure. Yet cluster-type filopodia (a precursor to synaptic filopodia were persistently significantly decreased in number on day-in-vitro 9, in part owing to preferential localization of drebrin immunoreactivity to dendritic shafts versus filopodial stalks. These data suggest that sevoflurane induces F-actin depolymerization leading to acute, reversible length-shortening in dendritic protrusions through a mechanism involving (in part activation of RhoA/Rho kinase signaling and impairs localization of drebrin A to filopodia required for early excitatory synapse formation.

  9. Ammonia volatilization from intensively managed dairy pastures.

    NARCIS (Netherlands)

    Bussink, D.W.

    1996-01-01

    The objectives of this thesis are (i) to quantify NH 3 volatilization from grassland, (ii) to gain understanding of the NH3 volatilization processes on grassland and (iii) to study measures how to reduce NH 3 volatilization from gra

  10. Oil Volatility Risk and Expected Stock Returns

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Pan, Xuhui (Nick)

    After the financialization of commodity futures markets in 2004-05 oil volatility has become a strong predictor of returns and volatility of the overall stock market. Furthermore, stocks' exposure to oil volatility risk now drives the cross-section of expected returns. The difference in average r...

  11. Volatiles in inter-specific bacterial interactions

    NARCIS (Netherlands)

    Tyc, O.; Zweers, H.; De Boer, W.; Garbeva, P.V.

    2015-01-01

    The importance of volatile organic compounds for functioning of microbes is receiving increased research attention. However, to date very little is known on how inter-specific bacterial interactions effect volatiles production as most studies have been focused on volatiles produced by monocultures o

  12. Cost Linkages Transmit Volatility Across Markets

    DEFF Research Database (Denmark)

    Nguyen, Daniel Xuyen; Schaur, Georg

    to link the domestic and export supply costs. This theoretical contribution has two new implications for the exporting firm. First, the demand volatility in the foreign market now directly affects the firm's domestic sales volatility. Second, firms hedge domestic demand volatility with exports. The model...

  13. Evaluation of Waste Anesthetic Gas in the Postanesthesia Care Unit within the Patient Breathing Zone

    Science.gov (United States)

    Hiller, Kenneth N.; Altamirano, Alfonso V.; Cai, Chunyan; Tran, Stephanie F.; Williams, George W.

    2015-01-01

    Potential health hazards from waste anesthetic gases (WAGs) have been a concern since the introduction of inhalational anesthetics into clinical practice. The potential to exceed recommended exposure levels (RELs) in the postanesthesia care unit (PACU) exists. The aim of this pilot study was to assess sevoflurane WAG levels while accounting for factors that affect inhalational anesthetic elimination. In this pilot study, 20 adult day surgery patients were enrolled with anesthesia maintained with sevoflurane. Following extubation, exhaled WAG from the patient breathing zone was measured 8 inches from the patient's mouth in the PACU. Maximum sevoflurane WAG levels in the patient breathing zone exceeded National Institute for Occupational Safety and Health (NIOSH) RELs for every 5-minute time interval measured during PACU Phase I. Observed WAGs in our study were explained by inhalational anesthetic pharmacokinetics. Further analysis suggests that the rate of washout of sevoflurane was dependent on the duration of anesthetic exposure. This study demonstrated that clinically relevant inhalational anesthetic concentrations result in sevoflurane WAG levels that exceed current RELs. Evaluating peak and cumulative sevoflurane WAG levels in the breathing zone of PACU Phase I and Phase II providers is warranted to quantify the extent and duration of exposure. PMID:26693222

  14. Evaluation of the effect of locally administered amitriptyline gel as adjunct to local anesthetics in irreversible pulpitis pain

    Directory of Open Access Journals (Sweden)

    Moghadamnia A

    2009-01-01

    Full Text Available Background: Amitriptyline is one of the most common tricyclic antidepressants, which binds to pain sensory nerve fibers close to the sodium channel; hence, it could interact to some degree with receptors of local anesthetics. This study was designed to assess the additional analgesic effects of 2% Amitriptyline local gel administration in irreversible pulpitis pain of the molars. Materials and Methods: This study was a randomized, double-blind clinical trial that was performed on 56 consented adult patients who did not receive enough analgesia after a lidocaine nerve block for their tooth pulpitis pain. Patients were treated with 0.2 ml of either 2% amitriptyline or placebo, which was directly injected into their mandibular molar pulp chamber after they had received two routine lidocaine injections. Patients were asked to score their pain as a mark on a 10-cm Visual Analogue Scale (VAS at different timepoints: 0 (just before gel administration, 1, 3, 5, 7, and 9 minutes after the treatments. Results: There was a 92.5% decrease in VAS scores of patients 9 minutes after amitriptyline administration compared to Time 0, while in the placebo group this difference was only 13.5%. Further, in the amitriptyline group, the VAS score at all timepoints was statistically different from Time 0 ( P < 0.01. The overall pain reduction and its trend was significantly higher in the amitriptyline group compared with the placebo group ( P < 0.001. Conclusion: Inter-pulp space administration of amitriptyline 2% gel for completing analgesia in irreversible pulpitis pain could be effective and useful as a conjunctive therapy to injections of local anesthetics.

  15. Anesthetic drug midazolam inhibits cardiac human ether-à-go-go-related gene channels: mode of action.

    Science.gov (United States)

    Vonderlin, Nadine; Fischer, Fathima; Zitron, Edgar; Seyler, Claudia; Scherer, Daniel; Thomas, Dierk; Katus, Hugo A; Scholz, Eberhard P

    2015-01-01

    Midazolam is a short-acting benzodiazepine that is in wide clinical use as an anxiolytic, sedative, hypnotic, and anticonvulsant. Midazolam has been shown to inhibit ion channels, including calcium and potassium channels. So far, the effects of midazolam on cardiac human ether-à-go-go-related gene (hERG) channels have not been analyzed. The inhibitory effects of midazolam on heterologously expressed hERG channels were analyzed in Xenopus oocytes using the double-electrode voltage clamp technique. We found that midazolam inhibits hERG channels in a concentration-dependent manner, yielding an IC50 of 170 μM in Xenopus oocytes. When analyzed in a HEK 293 cell line using the patch-clamp technique, the IC50 was 13.6 μM. Midazolam resulted in a small negative shift of the activation curve of hERG channels. However, steady-state inactivation was not significantly affected. We further show that inhibition is state-dependent, occurring within the open and inactivated but not in the closed state. There was no frequency dependence of block. Using the hERG pore mutants F656A and Y652A we provide evidence that midazolam uses a classical binding site within the channel pore. Analyzing the subacute effects of midazolam on hERG channel trafficking, we further found that midazolam does not affect channel surface expression. Taken together, we show that the anesthetic midazolam is a low-affinity inhibitor of cardiac hERG channels without additional effects on channel surface expression. These data add to the current understanding of the pharmacological profile of the anesthetic midazolam.

  16. Level Shifts in Volatility and the Implied-Realized Volatility Relation

    DEFF Research Database (Denmark)

    Christensen, Bent Jesper; de Magistris, Paolo Santucci

    to the multivariate case of the univariate level shift technique by Lu and Perron (2008). An application to the S&P500 index and a simulation experiment show that the recently documented empirical properties of strong persistence in volatility and forecastability of future realized volatility from current implied...... volatility, which have been interpreted as long memory (or fractional integration) in volatility and fractional cointegration between implied and realized volatility, are accounted for by occasional common level shifts....

  17. The economic value of realized volatility

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Feunou, Bruno; Jacobs, Kris

    2014-01-01

    Many studies have documented that daily realized volatility estimates based on intraday returns provide volatility forecasts that are superior to forecasts constructed from daily returns only. We investigate whether these forecasting improvements translate into economic value added. To do so, we...... develop a new class of affine discrete-time option valuation models that use daily returns as well as realized volatility. We derive convenient closed-form option valuation formulas, and we assess the option valuation properties using Standard & Poor’s (S&P) 500 return and option data. We find...... that realized volatility reduces the pricing errors of the benchmark model significantly across moneyness, maturity, and volatility levels....

  18. Pain and efficacy of local anesthetics for central venous access

    Directory of Open Access Journals (Sweden)

    William C Culp Jr

    2008-11-01

    Full Text Available William C Culp Jr1, Mohammed Yousaf2, Benjamin Lowry1, Timothy C McCowan3, William C Culp21Division of Cardiothoracic Anesthesiology, Scott and White Hospital, The Texas A&M University College of Medicine, Temple, TX, USA; 2Division of Interventional Radiology, University of Arkansas for Medical Sciences, Little Rock, AR, USA; 3Department of Radiology, University of Mississippi Medical Center, Jackson, MS, USAPurpose: To compare pain during injection and efficacy of analgesia of local anesthetics during central venous line placement.Methods: Sixty-two patients were studied in a randomized, double-blinded prospective fashion. Patients received 1% lidocaine (L, buffered 1% lidocaine (LB, or 2% chloroprocaine (CP injected around the internal jugular vein for procedural analgesia for central venous access. Patients reported pain via a standard linear visual analog scale, with 0 representing no pain and 10 being the worst pain imaginable.Results: Overall patient perception of pain was better with CP and L than LB with mean scores of CP 2.4, L 2.6, LB 4.2. Pain with injection mean scores were CP 2.1, L 2.5, LB 3.2. Pain with catheter placement scores were CP 2.5, L 1.7, LB 3.4. Operator assessment of overall pain values were CP 1.9, L 2.2, LB 3.4. LB consistently scored the worst, though compared with CP, this only reached statistical significance in overall patient pain and pain at catheter insertion compared with L.Conclusion: Though chloroprocaine scored better than lidocaine in 3 of 4 parameters, this trend did not achieve statistical significance. Adding sodium bicarbonate to lidocaine isn’t justified in routine practice, nor is routine replacement of lidocaine with chloroprocaine.Keywords: local anesthesia, analgesia, central venous access, lidocaine, chloroprocaine

  19. Anesthetic management in a patient with Kindler′s syndrome

    Directory of Open Access Journals (Sweden)

    Sohan Lal Solanki

    2011-01-01

    Full Text Available A 35-year-old male with pan-anterior urethral stricture was scheduled to undergo perineal urethrostomy. He was a known case of Kindler′s syndrome since infancy. He was having a history of blister formation, extensive poikiloderma and progressive cutaneous atrophy since childhood. He had a tendency of trauma-induced blisters with clear or hemorrhagic contents that healed with scarring. The fingers were sclerodermiform with dystrophic nails and inability to completely clench the fist. Airway examination revealed thyromental distance of 7 cm with limited neck extension, limited mouth opening and mallampatti class III with a fixed large tongue. He was reported as grade IV Cormack and Lehane laryngoscopic on previous anesthesia exposure. We described the anesthetic management of such case on guidelines for epidermolysis bullosa. In the operating room, an 18-G cannula was secured in the right upper limb using Coban TM Wrap. The T-piece of the cannula was than inserted into the slit and the tape was wrapped around the extremity. The ECG electrodes were placed on the limbs and fixed with Coban TM . Noninvasive blood pressure cuff was applied over the wrap after wrapping the arm with Webril® cotton. Oral fiberoptic tracheal intubation was done after lubricating the laryngoscope generously with a water-based lubricant with 7-mm endotracheal tube. Surgery proceeded without any complication. After reversing the residual neuromuscular block, trachea was extubated once the patient became awake. He was kept in the postanesthesia care unit for 2 hours and then shifted to urology ward.

  20. Cardiovascular responses to intrathecal administration of endomorphins in anesthetized rats.

    Science.gov (United States)

    Wang, Chang-Lin; Yu, Ye; Lai, Lu-Hao; Cui, Yun; Wang, Xiang; Wang, Rui

    2007-04-01

    Endomorphins (EMs), the endogenous, potent and selective mu-opioid receptor agonists, have been shown to decrease systemic arterial pressure (SAP) in rats after intravenous (i.v.) administration. In the present study, cardiovascular responses to intrathecal (i.t.) injection of EMs were investigated in urethane-anesthetized rats. It is noteworthy that EMs elicited decreases in SAP and heart rate (HR) in a dose-dependent manner; 10-300nmol/kg were injected intrathecally. Furthermore, these vasodepressor and bradycardic effects were significantly antagonized by naloxone (0.5mg/kg, i.t.). Interestingly, i.t. (5mg/kg) or i.v. (50mg/kg) administrations of N(omega)-nitro-l-arginine methylester (l-NAME) attenuated the vasodepressor and bradycardic effects. Moreover, pretreatment of the rats with muscarinic receptor antagonist atropine (2mg/kg, i.v.) and alpha-adrenoceptor antagonist phentolamine (1mg/kg, i.v.) significantly reduced the vasodepressor effects of EMs. Nevertheless, pretreatment with beta-adrenoceptor antagonist propranolol (2mg/kg, i.v.) could only block the bradycardia effects induced by EMs, but had no significant effects on the hypotension. In summary, all the results suggested that i.t. administration of EMs decreased SAP and HR which were possibly mediated by the activation of opioid receptors in the rat spinal cord. In addition, nitric oxide (NO) release in both the spinal cord and in peripheral tissues might regulate the cardiovascular activities of EMs, and the muscarinic receptor and adrenoceptor played an important role in the regulation of the cardiovascular responses to i.t. administration of EMs.

  1. Capsaicin facilitates carotid sinus baroreceptor activity in anesthetized rats

    Institute of Scientific and Technical Information of China (English)

    HaoZHANG; Yi-xianLIU; Yu-mingWU; Ze-minWANG; Rui-rongHE

    2004-01-01

    AIM: To study the effect of capsaicin on carotid sinus baroreceptor activity (CBA). METHODS: The functional curve of carotid baroreceptor (FCCB) was constructed and the functional parameters of carotid sinus baroreceptor were measured by recording sinus nerve afferent discharge in anesthetized rats with perfused isolated carotid sinus. RESULTS: Low-concentration of capsaicin (0.2μmol/L) had no significant effect on CBA, while perfusion of the isolated carotid sinus with middle-concentration of capsaicin (1μmol/L) could shift FCCB to the left and upward,with peak slope (PS) increased from (2.47%±0.14%)/mmHg to (2.88%±0.10%)/mmHg (P<0.05) and peak integral value of carotid sinus nerve discharge (PIV) enhanced from 211%±5% to 238%±6% (P<0.01). The threshold pressure (TP) and saturation pressure (SP) were significantly decreased from 68.0±1.1 to 62.7±1.0mmHg (P<0.01) and from 171.0±1.6 to 165.0±0.6 mmHg (P<0.01). By perfusing with high-concentration of capsaicin (5μmol/L), FCCB was shifted to the left and upward further and the changes of the functional parameters such as PS, TP, and SP were concentration-dependent. Pretreatment with ruthenium red (100μmol/L), an antagonist of vanilloid receptor subtype 1 (VR1), blocked the effect of capsaicin on CBA. Preperfusion with glibenclamide(20μmol/L), a KATP channel blocker, could eliminate the effect of capsaicin on CBA. CONCLUSION: Capsaicin exerts a facilitatory role on the isolated carotid baroreceptor in a concentration-dependent manner. The facilitatory action of capsaicin may be attributed to the opening of KATP channels mediated by VR1.

  2. Capsaicin facilitates carotid sinus baroreceptor activity in anesthetized rats

    Institute of Scientific and Technical Information of China (English)

    Hao ZHANG; Yi-xian LIU; Yu-ming WU; Ze-min WANG; Rui-rong HE

    2004-01-01

    AIM: To study the effect of capsaicin on carotid sinus baroreceptor activity (CBA). METHODS: The functional curve of carotid baroreceptor (FCCB) was constructed and the functional parameters of carotid sinus baroreceptor were measured by recording sinus nerve afferent discharge in anesthetized rats with perfused isolated carotid sinus.RESULTS: Low-concentration of capsaicin (0.2 μmol/L) had no significant effect on CBA, while perfusion of the isolated carotid sinus with middle-concentration of capsaicin (1 μmol/L) could shift FCCB to the left and upward,with peak slope (PS) increased from (2.47 %±0.14 %)/mmHg to (2.88 %±0.10 %)/mmHg (P<0.05) and peak integral value of carotid sinus nerve discharge (PIV) enhanced from 211%±5 % to 238 %±6 % (P<0.01). The threshold pressure (TP) and saturation pressure (SP) were significantly decreased from 68.0±1.1 to 62.7±1.0mmHg (P<0.01) and from 171.0±1.6 to 165.0±0.6 mmHg (P<0.01). By perfusing with high-concentration of capsaicin (5 μmol/L), FCCB was shifted to the left and upward further and the changes of the functional parameters such as PS, TP, and SP were concentration-dependent. Pretreatment with ruthenium red (100 μmol/L), an antagonist of vanilloid receptor subtype 1 (VR1), blocked the effect of capsaicin on CBA. Preperfusion with glibenclamide(20 μmol/L), a KATp channel blocker, could eliminate the effect of capsaicin on CBA. CONCLUSION: Capsaicin exerts a facilitatory role on the isolated carotid baroreceptor in a concentration-dependent manner. The facilitatory action of capsaicin may be attributed to the opening of KATP channels mediated by VR1.

  3. Perioperative anesthetic documentation: Adherence to current Australian guidelines

    Directory of Open Access Journals (Sweden)

    Islam Elhalawani

    2013-01-01

    Full Text Available Purpose: The lack of adequate perioperative documentation has legal implications and can potentially affect the quality and safety of patient care. Despite the presence of guidelines, the adequacy of perioperative documentation in Australasia has not been adequately assessed. The aim of this study is to assess the adequacy of anesthetic documentation on the pre and intraoperative encounters and to test the hypotheses that documentation is incomplete in the settings of emergency vs. elective procedures, regional vs. general anesthesia, and manual vs. electronic documentation. Materials and Methods: The study was an observational retrospective study in the setting of a 250-bed teaching hospital in metropolitan Adelaide, Australia. The perioperative records of 850 patients were analyzed. A scoring system was designed, based on a policy statement from the Australian and New Zealand College of Anesthetists and a survey of the hospital anesthetists. Scored and categorical data was analyzed using Chi-square test. Numerical data was analyzed using student t-test. The null hypothesis was accepted or rejected at 0.05 significance. Results: There were significant deficiencies in the adequacy of preanesthetic and intraoperative records. This has been shown to be true in all cases. Documentation was found to be poorer in the emergency setting when compared to elective cases (median scores 15 vs. 21 P = 0.03 as well as documentation of airway assessment for cases done solely under regional anesthesia (42 vs. 85%, P = 0.05. There were no significant differences in the adequacy of electronic vs. manual records ( P = 0.92. Conclusion: There are significant deficiencies in the adequacy of perioperative records. This has been shown to be true in all cases, but is especially so in emergency cases and for patients having only regional anesthesia.

  4. Forecasting volatility of crude oil markets

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sang Hoon [Department of Business Administration, Gyeongsang National University, Jinju, 660-701 (Korea); Kang, Sang-Mok; Yoon, Seong-Min [Department of Economics, Pusan National University, Busan, 609-735 (Korea)

    2009-01-15

    This article investigates the efficacy of a volatility model for three crude oil markets - Brent, Dubai, and West Texas Intermediate (WTI) - with regard to its ability to forecast and identify volatility stylized facts, in particular volatility persistence or long memory. In this context, we assess persistence in the volatility of the three crude oil prices using conditional volatility models. The CGARCH and FIGARCH models are better equipped to capture persistence than are the GARCH and IGARCH models. The CGARCH and FIGARCH models also provide superior performance in out-of-sample volatility forecasts. We conclude that the CGARCH and FIGARCH models are useful for modeling and forecasting persistence in the volatility of crude oil prices. (author)

  5. Chirospecific analysis of plant volatiles

    Energy Technology Data Exchange (ETDEWEB)

    Tkachev, A V [N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2007-10-31

    Characteristic features of the analysis of plant volatiles by enantioselective gas (gas-liquid) chromatography and gas chromatography/mass spectrometry are discussed. The most recent advances in the design of enantioselective stationary phases are surveyed. Examples of the preparation of the most efficient phases based on modified cyclodextrins are given. Current knowledge on the successful analytical resolution of different types of plant volatiles (aliphatic and aromatic compounds and mono-, sesqui- and diterpene derivatives) into optical antipodes is systematically described. Chiral stationary phases used for these purposes, temperature conditions and enantiomer separation factors are summarised. Examples of the enantiomeric resolution of fragrance compounds and components of plant extracts, wines and essential oils are given.

  6. Chirospecific analysis of plant volatiles

    Science.gov (United States)

    Tkachev, A. V.

    2007-10-01

    Characteristic features of the analysis of plant volatiles by enantioselective gas (gas-liquid) chromatography and gas chromatography/mass spectrometry are discussed. The most recent advances in the design of enantioselective stationary phases are surveyed. Examples of the preparation of the most efficient phases based on modified cyclodextrins are given. Current knowledge on the successful analytical resolution of different types of plant volatiles (aliphatic and aromatic compounds and mono-, sesqui- and diterpene derivatives) into optical antipodes is systematically described. Chiral stationary phases used for these purposes, temperature conditions and enantiomer separation factors are summarised. Examples of the enantiomeric resolution of fragrance compounds and components of plant extracts, wines and essential oils are given.

  7. Money, banks and endogenous volatility

    OpenAIRE

    Pere Gomis-Porqueras

    2000-01-01

    In this paper I consider a monetary growth model in which banks provide liquidity, and the government fixes a constant rate of money creation. There are two underlying assets in the economy, money and capital. Money is dominated in rate of return. In contrast to other papers with a larger set of government liabilities, I find a unique equilibrium when agents' risk aversion is moderate. However, indeterminacies and endogenous volatility can be observed when agents are relatively risk averse.

  8. Volatiles in Inter-Specific Bacterial Interactions.

    Science.gov (United States)

    Tyc, Olaf; Zweers, Hans; de Boer, Wietse; Garbeva, Paolina

    2015-01-01

    The importance of volatile organic compounds for functioning of microbes is receiving increased research attention. However, to date very little is known on how inter-specific bacterial interactions effect volatiles production as most studies have been focused on volatiles produced by monocultures of well-described bacterial genera. In this study we aimed to understand how inter-specific bacterial interactions affect the composition, production and activity of volatiles. Four phylogenetically different bacterial species namely: Chryseobacterium, Dyella, Janthinobacterium, and Tsukamurella were selected. Earlier results had shown that pairwise combinations of these bacteria induced antimicrobial activity in agar media whereas this was not the case for monocultures. In the current study, we examined if these observations were also reflected by the production of antimicrobial volatiles. Thus, the identity and antimicrobial activity of volatiles produced by the bacteria were determined in monoculture as well in pairwise combinations. Antimicrobial activity of the volatiles was assessed against fungal, oomycetal, and bacterial model organisms. Our results revealed that inter-specific bacterial interactions affected volatiles blend composition. Fungi and oomycetes showed high sensitivity to bacterial volatiles whereas the effect of volatiles on bacteria varied between no effects, growth inhibition to growth promotion depending on the volatile blend composition. In total 35 volatile compounds were detected most of which were sulfur-containing compounds. Two commonly produced sulfur-containing volatile compounds (dimethyl disulfide and dimethyl trisulfide) were tested for their effect on three target bacteria. Here, we display the importance of inter-specific interactions on bacterial volatiles production and their antimicrobial activities.

  9. Human skin volatiles: a review.

    Science.gov (United States)

    Dormont, Laurent; Bessière, Jean-Marie; Cohuet, Anna

    2013-05-01

    Odors emitted by human skin are of great interest to biologists in many fields; applications range from forensic studies to diagnostic tools, the design of perfumes and deodorants, and the ecology of blood-sucking insect vectors of human disease. Numerous studies have investigated the chemical composition of skin odors, and various sampling methods have been used for this purpose. The literature shows that the chemical profile of skin volatiles varies greatly among studies, and the use of different sampling procedures is probably responsible for some of these variations. To our knowledge, this is the first review focused on human skin volatile compounds. We detail the different sampling techniques, each with its own set of advantages and disadvantages, which have been used for the collection of skin odors from different parts of the human body. We present the main skin volatile compounds found in these studies, with particular emphasis on the most frequently studied body regions, axillae, hands, and feet. We propose future directions for promising experimental studies on odors from human skin, particularly in relation to the chemical ecology of blood-sucking insects.

  10. An estimation of the minimum effective anesthetic volume of 2% lidocaine in ultrasound-guided axillary brachial plexus block.

    LENUS (Irish Health Repository)

    O'Donnell, Brian D

    2009-07-01

    Ultrasound guidance facilitates precise needle and injectate placement, increasing axillary block success rates, reducing onset times, and permitting local anesthetic dose reduction. The minimum effective volume of local anesthetic in ultrasound-guided axillary brachial plexus block is unknown. The authors performed a study to estimate the minimum effective anesthetic volume of 2% lidocaine with 1:200,000 epinephrine (2% LidoEpi) in ultrasound-guided axillary brachial plexus block.

  11. Efficacy of Topical Anesthetics in the Treatment of Ingrown Nail

    Directory of Open Access Journals (Sweden)

    Fatma Gülru Erdoğan

    2011-06-01

    Full Text Available Background and Design: One of the reasons for preferring conservative methods for ingrown nails is lack of local anesthesia for the painful step. Moreover, ingrown nail is a painful condition per se. It may be very difficult to intervene patients with high basal pain levels. Here, we aimed to assess the efficacy of topical anesthetics (2.5% lidocaine, 2.5% prilocaine mixture and 20% benzocaine gel by determining basal pain level and pain during and after manipulation in patients with severe pain who applied with ingrown nail complaint.Material and Method: In this study, we included a total of 29 patients (12 male, 17 female who had complaint of ingrown nail and for whom nail brace treatment was planned. The patients were divided randomly into two groups regardless of the stage of ingrown nail: with lidocain-prilocain mixture application and with benzocaine gel application. Benzocaine gel was applied 10 minutes before the procedure and lidocaine-prilocaine mixture was applied under occlusion, 2 hours prior to the procedure. Pain levels were evaluated on a numerical pain rating scale before and after topical anesthesia as well as during and half an hour after the procedure in both groups.Results: Statistical difference was not detected between the pain levels of the two groups before and after topical anesthesia and during and half an hour after the procedure. Regardless of the stage of ingrown nail, the pain levels after topical anesthesia and half an hour after procedure were found to decrease significantly compared to the levels before topical anesthesia in both groups. Pain levels of both groups increased during the procedure and were similar to the basal levels. Considering the stage of ingrown nail, while lidocaine-prilocaine mixture did not decrease pain significantly in the cases with stage 2-3, benzocaine did. Conclusion: Due to ease of application and especially to efficacy in stage 2-3 ingrown nails, 20% benzocaine gel may help in

  12. Hypnosis control based on the minimum concentration of anesthetic drug for maintaining appropriate hypnosis.

    Science.gov (United States)

    Furutani, Eiko; Nishigaki, Yuki; Kanda, Chiaki; Takeda, Toshihiro; Shirakami, Gotaro

    2013-01-01

    This paper proposes a novel hypnosis control method using Auditory Evoked Potential Index (aepEX) as a hypnosis index. In order to avoid side effects of an anesthetic drug, it is desirable to reduce the amount of an anesthetic drug during surgery. For this purpose many studies of hypnosis control systems have been done. Most of them use Bispectral Index (BIS), another hypnosis index, but it has problems of dependence on anesthetic drugs and nonsmooth change near some particular values. On the other hand, aepEX has an ability of clear distinction between patient consciousness and unconsciousness and independence of anesthetic drugs. The control method proposed in this paper consists of two elements: estimating the minimum effect-site concentration for maintaining appropriate hypnosis and adjusting infusion rate of an anesthetic drug, propofol, using model predictive control. The minimum effect-site concentration is estimated utilizing the property of aepEX pharmacodynamics. The infusion rate of propofol is adjusted so that effect-site concentration of propofol may be kept near and always above the minimum effect-site concentration. Simulation results of hypnosis control using the proposed method show that the minimum concentration can be estimated appropriately and that the proposed control method can maintain hypnosis adequately and reduce the total infusion amount of propofol.

  13. History of T-cain: a local anesthetic developed and manufactured in Japan.

    Science.gov (United States)

    Tobe, Masaru; Saito, Shigeru

    2015-10-01

    In many anesthesia textbooks written in English, lidocaine, tetracaine, bupivacaine, ropivacaine, and chloroprocaine are listed as useful local anesthetics for spinal anesthesia. In contrast, T-cain is not included in these lists, even though it has been reported to be suitable for spinal anesthesia in Japan. T-cain was developed as a local anesthetic in the early 1940s by Teikoku Kagaku Sangyo Inc. in Itami, Japan, by replacing a methyl group on tetracaine (Pantocaine(®)) with an ethyl group. T-cain was clinically approved for topical use in Japan in November 1949, and a mixture of dibucaine and T-cain (Neo-Percamin S(®)) was approved for spinal use in May 1950. Simply because of a lack of foreign marketing strategy, T-cain has never attracted global attention as a local anesthetic. However, in Japan, T-cain has been used topically or intrathecally (as Neo-Percamin S(®)) for more than 60 years. Other than the side effects generally known for all local anesthetics, serious side effects have not been reported for T-cain. In fact, several articles have reported that T-cain decreases the neurotoxicity of dibucaine. In this historical review, the characteristics of T-cain and its rise to become a major spinal anesthetic in Japan are discussed.

  14. Advanced Pre-clinical Research Approaches and Models to Studying Pediatric Anesthetic Neurotoxicity

    Directory of Open Access Journals (Sweden)

    Cheng eWang

    2012-10-01

    Full Text Available Advances in pediatric and obstetric surgery have resulted in an increase in the duration and complexity of anesthetic procedures. A great deal of concern has recently arisen regarding the safety of anesthesia in infants and children. Because of obvious limitations, it is not possible to thoroughly explore the effects of anesthetic agents on neurons in vivo in human infants or children. However, the availability of some advanced pre-clinical research approaches and models, such as imaging technology both in vitro and in vivo, stem cell and nonhuman primate experimental models, have provided potentially invaluable tools for examining the developmental effects of anesthetic agents. This review discusses the potential application of some sophisticaled research approaches, e.g., calcium imaging, in stem cell-derived in vitro models, especially human embryonic neural stem cells, along with their capacity for proliferation and their potential for differentiation, to dissect relevant mechanisms underlying the etiology of the neurotoxicity associated with developmental exposures to anesthetic agents. Also, this review attempts to discuss several advantages for using the developing rhesus monkey models (in vivo, when combined with dynamic molecular imaging approaches, in addressing critical issues related to the topic of pediatric sedation/anesthesia. These include the relationships between anesthetic-induced neurotoxicity, dose response, time-course and developmental stage at time of exposure (in vivo studies, serving to provide the most expeditious platform toward decreasing the uncertainty in extrapolating pre-clinical data to the human condition.

  15. Impact of Anesthetics on Immune Functions in a Rat Model of Vagus Nerve Stimulation.

    Directory of Open Access Journals (Sweden)

    Chloé A Picq

    Full Text Available Vagus nerve stimulation (VNS has been successfully performed in animals for the treatment of different experimental models of inflammation. The anti-inflammatory effect of VNS involves the release of acetylcholine by vagus nerve efferent fibers inhibiting pro-inflammatory cytokines (e.g. TNF-α produced by macrophages. Moreover, it has recently been demonstrated that splenic lymphocytic populations may also be involved. As anesthetics can modulate the inflammatory response, the current study evaluated the effect of two different anesthetics, isoflurane and pentobarbital, on splenic cellular and molecular parameters in a VNS rat model. Spleens were collected for the characterization of lymphocytes sub-populations by flow cytometry and quantification of cytokines secretion after in vitro activation. Different results were observed depending on the anesthetic used. The use of isoflurane displayed a non-specific effect of VNS characterized by a decrease of most splenic lymphocytes sub-populations studied, and also led to a significantly lower TNF-α secretion by splenocytes. However, the use of pentobarbital brought to light immune modifications in non-stimulated animals that were not observed with isoflurane, and also revealed a specific effect of VNS, notably at the level of T lymphocytes' activation. These differences between the two anesthetics could be related to the anti-inflammatory properties of isoflurane. In conclusion, pentobarbital is more adapted than isoflurane in the study of the anti-inflammatory effect of VNS on an anesthetized rat model in that it allows more accurate monitoring of subtle immunomodulatory processes.

  16. Anesthetic activity of Brazilian native plants in silver catfish (Rhamdia quelen

    Directory of Open Access Journals (Sweden)

    Lenise de Lima Silva

    Full Text Available There is an increasing demand for inexpensive and safe anesthetics that can reduce fish stress caused by some procedures such as capture and handling. In this context, the present study evaluated the potential of essential oils (EO of three Brazilian native plants (Hesperozygis ringens, Lippia sidoides and Ocotea acutifolia as anesthetics for the silver catfish - Rhamdia quelen. Moreover, an analysis was made of the chemical composition of these oils and their influence on stress parameter. EO of H. ringens and O. acutifolia were effective as anesthetics, without behavioral side effects. EO of O. acutifolia (150 µL L-1 promoted an increase in blood glucose level. Regarding to the composition, pulegone accounts for 96.63% of the EO of H. ringens, and caryophyllene oxide amounts to 56.90% of the EO of O. acutifolia. Two chemotypes, thymol and carvacrol (68.40% and 67.89%, respectively were verified for EO of L. sidoides. Both samples of EO of L. sidoides showed anesthetic activity in silver catfish, but exposure also caused loss of mucus and mortality. Thus, only the EO of H. ringens and O. acutifolia are advised for anesthetic use

  17. Origin of Volatiles in Earth: Indigenous Versus Exogenous Sources Based on Highly Siderophile, Volatile Siderophile, and Light Volatile Elements

    Science.gov (United States)

    Righter, K.; Danielson, L.; Pando, K. M.; Marin, N.; Nickodem, K.

    2015-01-01

    Origin of Earth's volatiles has traditionally been ascribed to late accretion of material after major differentiation events - chondrites, comets, ice or other exogenous sources. A competing theory is that the Earth accreted its volatiles as it was built, thus water and other building blocks were present early and during differentiation and core formation (indigenous). Here we discuss geochemical evidence from three groups of elements that suggests Earth's volatiles were acquired during accretion and did not require additional sources after differentiation.

  18. Inhibition of human two-pore domain K+ channel TREK1 by local anesthetic lidocaine: negative cooperativity and half-of-sites saturation kinetics.

    Science.gov (United States)

    Nayak, Tapan K; Harinath, S; Nama, S; Somasundaram, K; Sikdar, S K

    2009-10-01

    TWIK-related K+ channel TREK1, a background leak K+ channel, has been strongly implicated as the target of several general and local anesthetics. Here, using the whole-cell and single-channel patch-clamp technique, we investigated the effect of lidocaine, a local anesthetic, on the human (h)TREK1 channel heterologously expressed in human embryonic kidney 293 cells by an adenoviral-mediated expression system. Lidocaine, at clinical concentrations, produced reversible, concentration-dependent inhibition of hTREK1 current, with IC(50) value of 180 muM, by reducing the single-channel open probability and stabilizing the closed state. We have identified a strategically placed unique aromatic couplet (Tyr352 and Phe355) in the vicinity of the protein kinase A phosphorylation site, Ser348, in the C-terminal domain (CTD) of hTREK1, that is critical for the action of lidocaine. Furthermore, the phosphorylation state of Ser348 was found to have a regulatory role in lidocaine-mediated inhibition of hTREK1. It is interesting that we observed strong intersubunit negative cooperativity (Hill coefficient = 0.49) and half-of-sites saturation binding stoichiometry (half-reaction order) for the binding of lidocaine to hTREK1. Studies with the heterodimer of wild-type (wt)-hTREK1 and Delta119 C-terminal deletion mutant (hTREK1(wt)-Delta119) revealed that single CTD of hTREK1 was capable of mediating partial inhibition by lidocaine, but complete inhibition necessitates the cooperative interaction between both the CTDs upon binding of lidocaine. Based on our observations, we propose a model that explains the unique kinetics and provides a plausible paradigm for the inhibitory action of lidocaine on hTREK1.

  19. Volatile accretion history of the Earth.

    Science.gov (United States)

    Wood, B J; Halliday, A N; Rehkämper, M

    2010-10-28

    It has long been thought that the Earth had a protracted and complex history of volatile accretion and loss. Albarède paints a different picture, proposing that the Earth first formed as a dry planet which, like the Moon, was devoid of volatile constituents. He suggests that the Earth's complement of volatile elements was only established later, by the addition of a small veneer of volatile-rich material at ∼100 Myr (here and elsewhere, ages are relative to the origin of the Solar System). Here we argue that the Earth's mass balance of moderately volatile elements is inconsistent with Albarède's hypothesis but is well explained by the standard model of accretion from partially volatile-depleted material, accompanied by core formation.

  20. Volatile communication in plant-aphid interactions.

    Science.gov (United States)

    de Vos, Martin; Jander, Georg

    2010-08-01

    Volatile communication plays an important role in mediating the interactions between plants, aphids, and other organisms in the environment. In response to aphid infestation, many plants initiate indirect defenses through the release of volatiles that attract ladybugs, parasitoid wasps, and other aphid-consuming predators. Aphid-induced volatile release in the model plant Arabidopsis thaliana requires the jasmonate signaling pathway. Volatile release is also induced by infection with aphid-transmitted viruses. Consistent with mathematical models of optimal transmission, viruses that are acquired rapidly by aphids induce volatile release to attract migratory aphids, but discourage long-term aphid feeding. Although the ecology of these interactions is well-studied, further research is needed to identify the molecular basis of aphid-induced and virus-induced changes in plant volatile release.

  1. Effects of hyperthermia on binding, internalization, and degradation of epidermal growth factor. [/sup 125/I

    Energy Technology Data Exchange (ETDEWEB)

    Magun, B.E.; Fennie, C.W.

    1981-04-01

    /sup 125/I-epidermal growth factor was used as a molecular probe to study the effects of hyperthermia and local anesthetics on cultured Rat-1 cells. Heating cells at 45/sup 0/C for times up to 1 h caused a continuous decrease in EGF binding. Scatchard analysis showed that the decreased binding resulted from a decrease in the affinity of the EGF receptors rather than from a decrease in receptor number. Exposure to 42/sup 0/C had no effect on degradation. We compared the effects of heat to those caused by the local anesthetics procaine the lidocaine, which have been shown to prevent EGF degradation. Because procaine and lidocaine have been shown by others to potentiate the killing effects of hyperthermia on tumors and in cultured cells, we suggest that hyperthermia and the local anesthetics may act at the same cellular site. By inhibiting the action of lysosomes, hyperthermia and local anesthetics may permit potentially toxic materials to enter the cell by endocytosis, where they would accumulate and induce lethal damage.

  2. Volatile Constituents of Zhumaria Majdae

    Directory of Open Access Journals (Sweden)

    Yazdanparst

    1993-07-01

    Full Text Available Capillary gas chromatography mass spectrometry (GC- MS analyses of a sample of essential oil of zhumaria Linalool ned by simple water distillation of the pulverized air - dired leaves and flowers of the plant indicated that Linalool and comphor are the two major constituents of the volatile oil. Sylvestrene , y -terpinene, a- Pinene, b - carene, camphene, and Epiborneol constitute the other main components of the essential oil. The GC - MS chromatogram indicated the presence of more than fifty - components in the oil, most of them were present in trace amounts. In this study, the chemical structures of twenty of these consti tuents were elucidated using GC - MS analysis.

  3. Volatiles Which Increase Magma Viscosity

    Science.gov (United States)

    Webb, S.

    2015-12-01

    The standard model of an erupting volcano is one in which the viscosity of a decompressing magma increases as the volatiles leave the melt structure to form bubbles. It has now been observed that the addition of the "volatiles" P, Cl and F result in an increase in silicate melt viscosity. This observation would mean that the viscosity of selected degassing magmas would decrease rather than increase. Here we look at P, Cl and F as three volatiles which increase viscosity through different structural mechanisms. In all three cases the volatiles increase the viscosity of peralkaline composition melts, but appear to always decrease the viscosity of peraluminous melts. Phosphorus causes the melt to unmix into a Na-P rich phase and a Na-poor silicate phase. Thus as the network modifying Na (or Ca) are removed to the phosphorus-rich melt, the matrix melt viscosity increases. With increasing amounts of added phosphorus (at network modifying Na ~ P) the addition of further phosphorus causes a decrease in viscosity. The addition of chlorine to Fe-free aluminosilicate melts results in an increase in viscosity. NMR data on these glass indicates that the chlorine sits in salt-like structures surrounded by Na and/or Ca. Such structures would remove network-modifying atoms from the melt structure and thus result in an increase in viscosity. The NMR spectra of fluorine-bearing glasses shows that F takes up at least 5 different structural positions in peralkaline composition melts. Three of these positions should result in a decrease in viscosity due to the removal of bridging oxygens. Two of the structural positons of F, however, should result in an increase in viscosity as they require the removal of network-modifying atoms from the melt structure (with one of the structures being that observed for Cl). This would imply that increasing amounts of F might result in an increase in viscosity. This proposed increase in viscosity with increasing F has now been experimentally confirmed.

  4. The Determinants of Public Deficit Volatility

    OpenAIRE

    2009-01-01

    This paper empirically analyzes the political, institutional and economic sources of public deficit volatility. Using the system-GMM estimator for linear dynamic panel data models and a sample of 125 countries analyzed from 1980 to 2006, we show that higher public deficit volatility is typically associated with higher levels of political instability and less democracy. In addition, public deficit volatility tends to be magnified for small countries, in the outcome of hyper-inflation episodes ...

  5. DOES VOLATILITY RESPOND ASYMMETRIC TO PAST SHOCKS?

    OpenAIRE

    Claudiu Botoc

    2014-01-01

    The main aim of the paper is to examine if the stock market volatility exhibits asymmetric or an asymmetric response to past shocks, for certain CEE countries (Romania,Hungary, Bulgaria, Poland) over the period May 2004 - September 2014. For the stock marketsfrom East Europe the results are in line with the symmetric volatility, i.e. volatility is similaraffected by both positive and negative returns with the same magnitude. For the stock marketsfrom Central Europe the results are consistent ...

  6. Exchange Rate Volatility in BRICS Countries

    OpenAIRE

    2012-01-01

    This paper measures the impact of bilateral exchange rates, the world agricultural GDP and third-country exchange rate volatilities (Yen/USD and Euro/USD) on the BRICS agricultural exports using a vector autoregressive (VAR) model. Two measures of volatility are used: the standard deviation and the coefficient of variation of the rates of change of the real exchange rates. We found that most variables are integrated of order two except the third-country exchange rate volatilities which are st...

  7. Milk Price Volatility and its Determinants

    OpenAIRE

    Dong, Fengxia; Du, Xiaodong; Gould, Brian W.

    2011-01-01

    The classified pricing of fluid milk under the Federal Milk Marketing Orders (FMMO) system combined with the cash settlement feature of Class IIII milk futures contracts generate a unique volatility pattern of these futures markets in the sense that the volatility gradually decreases as the USDA price announcement dates approaching in the month. Focusing on the evolution of volatility in Class III milk futures market, this study quantifies the relative importance of a set of factors driving m...

  8. The relation between the duty cycle and anesthetic effect in lidocaine iontophoresis using alternating current.

    Science.gov (United States)

    Wakita, Ryo; Nakajima, Atsushi; Haida, Yu; Umino, Masahiro; Fukayama, Haruhisa

    2011-01-01

    We assessed the effect of the duty cycle on the anesthetic effect during lidocaine alternating current (AC) iontophoresis. A solution of 2% lidocaine was delivered to the medial antecubital skin for 20 minutes using AC iontophoresis with a duty cycle of 60%, 70%, or 80%. The von Frey test was then performed to evaluate the anesthetic effect. In the groups treated with a duty cycle of 80% or 70% the touch thresholds (TT) were significantly elevated from 0 minutes to 30 minutes and from 0 minutes to 20 minutes. TT were significantly elevated at 0 minutes in the group treated with a 60% duty cycle. The anesthetic effect was significantly enhanced in a duty cycle-dependent manner.

  9. The modifying effect of anesthetic technique on the metabolic and endocrine responses to anesthesia and surgery

    DEFF Research Database (Denmark)

    Kehlet, H

    1988-01-01

    and the widespread use of the term "stress free anesthesia" in surgery is therefore not valid. However, continuous administration of local anesthetic agents in the epidural space is the most effective technique in so far as reduction of the stress response is concerned. The clinical implication of a variable...... reduction in the stress response to surgery by different anesthetic techniques remains largely unsettled, since only few controlled studies have been published on the clinical effects of pain relief and general anesthesia. However, a vast amount of data exist from controlled studies comparing regional...... anesthesia with local anesthetics and general anesthesia. The cumulative experience from these studies have demonstrated an advantageous effect on postoperative morbidity parameters such as blood loss, postoperative thromboembolic complications, pulmonary infective complications, gastrointestinal motility...

  10. Laparoscopic colectomy in an adult with single ventricle physiology: Anesthetic implications and management

    Directory of Open Access Journals (Sweden)

    Kelly J Zach

    2015-01-01

    Full Text Available Increasing numbers of adult patients with complex congenital heart conditions are presenting for noncardiac surgery later in life. These disorders can present challenges for surgical and anesthesia providers. Specifically, single ventricle lesions offer anatomic and physiologic concerns during the perioperative period. Single ventricle physiology represents a delicate balance between systemic and pulmonary blood flow. Any alterations in blood flow through these systems can produce undesirable hemodynamic changes, especially during the perioperative period. We present a case of an adult patient with a single left ventricle who presented for laparoscopic total colectomy due to inflammatory bowel disease. His abnormal anatomy coupled with the hemodynamic disruptions caused by laparoscopy presented significant anesthetic challenges. We highlight the anesthetic concerns of single ventricle physiology, specifically pertaining to laparoscopic surgery. We provide recommendations for safely managing these patients perioperatively. With detailed preoperative evaluation and close hemodynamic monitoring during the perioperative period, these patients can experience successful surgical and anesthetic outcomes.

  11. Anesthetic Management of a Patient With Charcot-Marie-Tooth Disease.

    Science.gov (United States)

    Ohshita, Naohiro; Oka, Saeko; Tsuji, Kaname; Yoshida, Hiroaki; Morita, Shosuke; Momota, Yoshihiro; Tsutsumi, Yasuo M

    2016-01-01

    Charcot-Marie-Tooth disease (CMTD) is a hereditary peripheral neuropathy and is characterized by progressive muscle atrophy and motor-sensory disorders in all 4 limbs. Most reports have indicated that major challenges with general anesthetic administration in CMTD patients are the appropriate use of nondepolarizing muscle relaxants and preparation for malignant hyperthermia in neuromuscular disease. Moderate sedation may be associated with the same complications as those of general anesthesia, as well as dysfunction of the autonomic nervous system, reduced perioperative respiratory function, difficulty in positioning, and sensitivity to intravenous anesthetic agents. We decided to use intravenous sedation in a CMTD patient and administered midazolam initially and propofol continuously, with total doses of 1.5 mg and 300 mg, respectively. Anesthesia was completed in 3 hours and 30 minutes without adverse events. We suggest that dental anesthetic treatment with propofol and midazolam may be effective for patients with CMTD.

  12. [Perioperative risk factors and anesthetic management of patients for carotid endarterectomy].

    Science.gov (United States)

    Niinai, H; Nakagawa, I; Shima, T; Kubota, M; Yamada, K; Kamiya, T; Yoshida, A; Yasuda, T

    1997-05-01

    Data from the records of 142 patients for carotid endarterectomy at Chugoku Rosai General Hospital between 1983 and 1995, were evaluated concerning perioperative risk factors and anesthetic management. As a preoperative anesthetic risk, the incidence of hypertension was the commonest (76%), and there was a significant incidence of ischemic heart disease (18%). Fentanyl and isoflurane have been used for anesthesia recently and the patients were closely observed and cared in the intensive care unit postoperatively. In order to prevent cerebral ischemia during the occlusion of the internal carotid artery, we measured somatosensory evoked potential as well as jugular venous oxygen saturation, and used near infrared spectophotometry. As a result, postoperative mortality and morbidity were 0% and 2%, respectively. The candidates for CEA have potentially high perioperative risks, and it is important to evaluate the coexisting diseases and to select proper anesthetic technic and monitors.

  13. Combined use of intravenous anesthetics and hypothermia in treating refractory status epilepticus

    Directory of Open Access Journals (Sweden)

    Guo-ping REN

    2015-11-01

    Full Text Available The primary choice of treating refractory status epilepticus (RSE is intravenous anesthetics, but the seizures of some patients can not get a good control. Thus, other therapies must be combined. Hypothermia not only can terminate seizures, but also play a part in brain protection. Though combined use of intravenous anesthetics and hypothermia is not a regular clinical scheme, the favorable effect has been proved by a lot of clinical research. This paper mainly focuses on the dose of intravenous anesthetics, the time, temperature and procedure of hypothermia, the indications and contraindications of combined therapy, and so on. DOI: 10.3969/j.issn.1672-6731.2015.11.006

  14. Mars Accreted a Volatile Element-Depleted Late Veneer Indicating Early Delivery of Martian Volatiles

    Science.gov (United States)

    Becker, H.; Wang, Z.

    2016-08-01

    Chalcophile elements in SNC meteorites are used to constrain abundances in the Martian mantle. Strong depletion of Te relative to highly siderophile elements suggests a volatile element-depleted late veneer, requiring that volatiles arrived earlier.

  15. [Solidification of volatile oil with graphene oxide].

    Science.gov (United States)

    Yan, Hong-Mei; Jia, Xiao-Bin; Zhang, Zhen-Hai; Sun, E; Xu, Yi-Hao

    2015-02-01

    To evaluate the properties of solidifying volatile oil with graphene oxide, clove oil and zedoary turmeric oil were solidified by graphene oxide. The amount of graphene oxide was optimized with the eugenol yield and curcumol yield as criteria. Curing powder was characterized by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The effects of graphene oxide on dissolution in vitro and thermal stability of active components were studied. The optimum solidification ratio of graphene oxide to volatile oil was 1:1. Dissolution rate of active components had rare influence while their thermal stability improved after volatile oil was solidified. Solidifying herbal volatile oil with graphene oxide deserves further study.

  16. CAM Stochastic Volatility Model for Option Pricing

    Directory of Open Access Journals (Sweden)

    Wanwan Huang

    2016-01-01

    Full Text Available The coupled additive and multiplicative (CAM noises model is a stochastic volatility model for derivative pricing. Unlike the other stochastic volatility models in the literature, the CAM model uses two Brownian motions, one multiplicative and one additive, to model the volatility process. We provide empirical evidence that suggests a nontrivial relationship between the kurtosis and skewness of asset prices and that the CAM model is able to capture this relationship, whereas the traditional stochastic volatility models cannot. We introduce a control variate method and Monte Carlo estimators for some of the sensitivities (Greeks of the model. We also derive an approximation for the characteristic function of the model.

  17. Assessing Relative Volatility/Intermittency/Energy Dissipation

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole E.; Pakkanen, Mikko; Schmiegel, Jürgen

    We introduce the notion of relative volatility/intermittency and demonstrate how relative volatility statistics can be used to estimate consistently the temporal variation of volatility/intermittency even when the data of interest are generated by a non-semimartingale, or a Brownian semistationary...... process in particular. While this estimation method is motivated by the assessment of relative energy dissipation in empirical data of turbulence, we apply it also to energy price data. Moreover, we develop a probabilistic asymptotic theory for relative power variations of Brownian semistationary...... processes and Ito semimartingales and discuss how it can be used for inference on relative volatility/intermittency....

  18. Evaluation of Surface anesthetic action of Aqueous Extract of Piper Betel leaf On Rabbit Cornea

    Directory of Open Access Journals (Sweden)

    Dr.T.Jayasree

    2014-07-01

    Full Text Available Aim: Piper betel Linn. (Piperaceae commonly known as betel leaf and the habit of betel chewing is widely prevalent in most parts of India. It is claimed to have aphrodisiac, laxative, antimicrobial, mucolytic, antiinflammatory and euphoric properties and proven antimutagenic and anti-carcinogenic effect. It is commonly observed that chewing of betel leaf produces numbness in the mouth, suggesting a possible local anesthetic effect. This observation prompted us to take this study . The aim of the study was to evaluate the local anesthetic activity of betel leaf extract after autoclaving the extract of betel leaf. Materials and methods: Extract of plain betel leaf, was tested for surface anesthetic activity using rabbits. Aqueous extraction of Piper betel leaf (AEPBL done by Soxhelts apparatus .Twenty male Rabbit’s were taken and divided in to four groups each group contain 5 animals, Group I - Standard (2% xylocaine, Group II - Test 0.3% (AEPBL, Group III - Test 0.6 % (AEPBL,Group IV - Test 12 % (AEPBL was instilled in conjunctival sac of right eyes. Standard protocol was followed to elicit light reflex, corneal reflex and to measure pupillary size after instilling the test drugs in the eye. There was dose dependent increase in onset and duration of local anesthetic activity with 6% and 12% doses of alcoholic extract of Piper betel leaf. Results: Betel leaf showed significant surface anesthetic activity comparable to that of Xylocaine. Conclusion: As a surface anesthetic, the onset was as quick as xylocaine and the duration was shorter than xylocaine

  19. General anesthetics have differential inhibitory effects on gap junction channels and hemichannels in astrocytes and neurons.

    Science.gov (United States)

    Liu, Xinhe; Gangoso, Ester; Yi, Chenju; Jeanson, Tiffany; Kandelman, Stanislas; Mantz, Jean; Giaume, Christian

    2016-04-01

    Astrocytes represent a major non-neuronal cell population actively involved in brain functions and pathologies. They express a large amount of gap junction proteins that allow communication between adjacent glial cells and the formation of glial networks. In addition, these membrane proteins can also operate as hemichannels, through which "gliotransmitters" are released, and thus contribute to neuroglial interaction. There are now reports demonstrating that alterations of astroglial gap junction communication and/or hemichannel activity impact neuronal and synaptic activity. Two decades ago we reported that several general anesthetics inhibited gap junctions in primary cultures of astrocytes (Mantz et al., (1993) Anesthesiology 78(5):892-901). As there are increasing studies investigating neuroglial interactions in anesthetized mice, we here updated this previous study by employing acute cortical slices and by characterizing the effects of general anesthetics on both astroglial gap junctions and hemichannels. As hemichannel activity is not detected in cortical astrocytes under basal conditions, we treated acute slices with the endotoxin LPS or proinflammatory cytokines to induce hemichannel activity in astrocytes, which in turn activated neuronal hemichannels. We studied two extensively used anesthetics, propofol and ketamine, and the more recently developed dexmedetomidine. We report that these drugs have differential inhibitory effects on gap junctional communication and hemichannel activity in astrocytes when used in their respective, clinically relevant concentrations, and that dexmedetomidine appears to be the least effective on both channel functions. In addition, the three anesthetics have similar effects on neuronal hemichannels. Altogether, our observations may contribute to optimizing the selection of anesthetics for in vivo animal studies.

  20. New procedure to synthesize silver nanoparticles and their interaction with local anesthetics

    Directory of Open Access Journals (Sweden)

    Mocanu A

    2013-10-01

    Full Text Available Aurora Mocanu,1 Roxana Diana Pasca,1 Gheorghe Tomoaia,2 Corina Garbo,1 Petre T Frangopol,1 Ossi Horovitz,1 Maria Tomoaia-Cotisel11Chemical Engineering Department, Babes-Bolyai University, 2Orthopedic Department, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, RomaniaAbstract: Silver nanoparticles (AgNPs were prepared in aqueous colloid dispersions by the reduction of Ag+ with glucose in alkaline medium. Tetraethyl orthosilicate and l-asparagine were added as stabilizers of NPs. The AgNPs were characterized, and their interaction with three local anesthetics (procaine, dibucaine, or tetracaine was investigated. Optical spectra show the characteristic absorption band of AgNPs, due to surface plasmon resonance. Modifications in the position and shape of this band reflect the self-assembly of metal NPs mediated by anesthetic molecules and the progress in time of the aggregation process. Zeta-potential measuring was applied in order to characterize the electrostatic stability of the NPs. The size and shape of the AgNPs, as well as the features of the assemblies formed by their association in the presence of anesthetics, were evidenced by transmission electron microscopy images. Atomic force microscopy images showed the characteristics of the films of AgNPs deposited on glass support. The effect of the anesthetics could be described in terms of electrostatic forces between the negatively charged AgNPs and the anesthetic molecules, existing also in their cationic form at the working pH. But also hydrophobic and hydrogen bonding interactions between the coated nanoparticles and anesthetics molecular species should be considered.Keywords: self-assembled nanostructures, UV-vis spectra, TEM, AFM, zeta potential

  1. Myocardial perfusion of infarcted and normal myocardium in propofol-anesthetized minipigs using 82Rubidium PET

    DEFF Research Database (Denmark)

    Rasmussen, Thomas; Larsen, Bjarke Follin; Kastrup, Jens;

    2016-01-01

    challenges. Animals, which have been anesthetized during PET acquisition, might react differently to used stress medications, and therefore difficulties might exist while evaluating the resulting PET images using standard software packages from commercial vendors optimized for human hearts. Furthermore...... propofol, used for anesthesia, can influence myocardial perfusion and coronary flow reserve due to its vasorelaxant effect, and interactions might exist between propofol and used stress agents, potentially affecting the result of the examination. We present cardiac 82Rb-PET studies performed in propofol-anesthetized...

  2. Anesthetic management of a patient with Kimura′s disease for superficial parotidectomy

    Directory of Open Access Journals (Sweden)

    Dalim Kumar Baidya

    2011-01-01

    Full Text Available Kimura′s disease is a rare form of chronic eosinophilic inflammatory disease with vascular proliferation involving salivary gland, skin, lymph node, and kidney. Important anesthetic concerns include increased surgical bleeding due to its vascular nature, airway involvement by the mass leading to a possible difficult airway, allergic symptoms associated with high eosinophil count and elevated IgE level and nephrotic syndrome due to involvement of kidney by the inflammatory process. There is paucity of information in the literature on the anesthetic management of Kimura′s disease. We describe the anesthesia technique and review the literature of such a case posted for superficial parotidectomy.

  3. Algorithmic complexity as an index of cortical function in awake and pentobarbital-anesthetized rats.

    Science.gov (United States)

    Shaw, F Z; Chen, R F; Tsao, H W; Yen, C T

    1999-11-15

    This study introduces algorithmic complexity to measure characteristics of brain functions. The EEG of the rat was recorded with implanted electrodes. The normalized complexity value was relatively independent of data length, and it showed a simpler and easier calculation characteristic than other non-linear indexes. The complexity index revealed significant differences among awake, asleep, and anesthetized states. It may be useful in tracking short-term and long-term changes in brain functions, such as anesthetized depth, drug effects, or sleep-wakefulness.

  4. Comparison of Intravenous Anesthetic Agents for the Treatment of Refractory Status Epilepticus

    Directory of Open Access Journals (Sweden)

    Michael E. Reznik

    2016-05-01

    Full Text Available Status epilepticus that cannot be controlled with first- and second-line agents is called refractory status epilepticus (RSE, a condition that is associated with significant morbidity and mortality. Most experts agree that treatment of RSE necessitates the use of continuous infusion intravenous anesthetic drugs such as midazolam, propofol, pentobarbital, thiopental, and ketamine, each of which has its own unique characteristics. This review compares the various anesthetic agents while providing an approach to their use in adult patients, along with possible associated complications.

  5. Anesthetic management of a neonate with arthrogryposis multiplex congenita for emergency laparotomy

    Directory of Open Access Journals (Sweden)

    Rajat Chowdhuri

    2011-01-01

    Full Text Available Arthrogryposis multiplex congenita is a rare disease, characterized by non-progressive, multiple joint contractures since birth. Anesthetic issues include difficult intravenous access, difficult airway management and regional anesthesia. We report the anesthetic management of a six-day-old neonate presenting to the emergency with features of intestinal obstruction, who was detected for the first time to have arthrogryposis multiplex congenita. General anesthesia along with caudal analgesia for peroperative and postoperative pain relief was used. There was an episode of intraoperative hyperthermia, which was tackled successfully. The child had an uneventful post-anesthesia recovery.

  6. The application of a non-linear analysis technique to the monitoring of anesthetic effects in the rat

    NARCIS (Netherlands)

    Broek, P.L.C. van den; Egmond, J. van; Rijn, C.M. van; Dirksen, R.; Coenen, A.M.L.; Booij, L.H.D.J.

    2000-01-01

    To find a new measure from the EEG that quantifies the effects of anesthetics during surgery, the correlation dimension (CD) of the EEG of eight rats was estimated. To get informed about the anesthetic state, the noxious induced withdrawal reflex (NIWR) was measured, i.e. the force elicited by trans

  7. Isoflurane anesthetic hypersensitivity and progressive respiratory depression in a mouse model with isolated mitochondrial complex I deficiency

    NARCIS (Netherlands)

    Roelofs, S.; Manjeri, G.R.; Willems, P.H.G.M.; Scheffer, G.J.; Smeitink, J.A.M.; Driessen, J.J.

    2014-01-01

    BACKGROUND: Children with mitochondrial disorders are frequently anesthetized for a wide range of operations. These disorders may interfere with the response to surgery and anesthesia. We examined anesthetic sensitivity to and respiratory effects of isoflurane in the Ndufs4 knockout (KO) mouse model

  8. Sympathoexcitation of moxonidine in the caudal ventrolateral medulla is dependent on I1-imidazoline receptors in anesthetized rats.

    Science.gov (United States)

    Wang, Li-Gang; Gao, Lie; Wang, Wei; Yuan, Wen-Jun; Wang, Wei-Zhong

    2007-10-16

    Moxonidine is a second-generation centrally acting antihypertensive drug that has a high affinity for I(1)-imidazoline receptors (I(1)R). The caudal ventrolateral medulla (CVLM), an important region involved in cardiovascular activity, contains binding sites for centrally acting drugs. Our study aimed to determine the effects of moxonidine injected into the CVLM on cardiovascular activity in anesthetized rats. Unilateral microinjection of moxonidine (0.4 and 4 nmol) into the CVLM dose-dependently increased blood pressure (BP) by 8+/-2 and 18+/-2 mmHg and renal sympathetic nerve activity (RSNA) by 19+/-3 and 48+/-5% without modifying heart rate. Microinjection of the I(1)R/alpha(2)-adrenoceptor antagonist efaroxan (4 nmol) into the CVLM produced significant decreases in baseline BP and RSNA, but also completely abolished the increases in BP (2+/-1 versus 18+/-2 mmHg, P0.05) effect on the moxonidine-induced increase in BP (18+/-2 versus 17+/-3 mmHg) and RSNA (45+/-10 versus 42+/-7%). The current data suggest that moxonidine injection into the CVLM has an excitatory effect on cardiovascular activity, which is mediated by an I(1)R dependent mechanism.

  9. Local anesthetics after total knee arthroplasty: intraarticular or extraarticular administration? A randomized, double-blind, placebo-controlled study

    DEFF Research Database (Denmark)

    Andersen, L.O.; Kristensen, B.B.; Husted, H.;

    2008-01-01

    BACKGROUND: High-volume local infiltration analgesia with additional intraarticular and wound administration of local anesthetic has been shown to be effective after knee replacement, but the optimum site of administration of the local anesthetic (i.e. intraarticular or extraarticular) has not been...... or to receive 20 mL ropivacaine (0.2%) intraarticularly plus 30 mL ropivacaine (0.2%) in the extraarticular wound space 24 hours postoperatively. Pain intensity at rest and with mobilization was recorded for 4 hours after administration of additional local anesthetics. RESULTS: Intensity of pain at rest, during...... flexion, or straight leg lift was not statistically significantly different between the two groups, but there was a tendency of improved analgesia with administration of additional local anesthetic in the extraarticular wound space. INTERPRETATION: The optimal site of administration of local anesthetic...

  10. Analyzing volatile compounds in dairy products

    Science.gov (United States)

    Volatile compounds give the first indication of the flavor in a dairy product. Volatiles are isolated from the sample matrix and then analyzed by chromatography, sensory methods, or an electronic nose. Isolation may be performed by solvent extraction or headspace analysis, and gas chromatography i...

  11. Volatility Determination in an Ambit Process Setting

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole; Graversen, Svend-Erik

    The probability limit behaviour of normalised quadratic variation is studied for a simple tempo-spatial ambit process, with particular regard to the question of volatility memorylessness.......The probability limit behaviour of normalised quadratic variation is studied for a simple tempo-spatial ambit process, with particular regard to the question of volatility memorylessness....

  12. Some recent developments in stochastic volatility modelling

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler; Nicolato, Elisa; Shephard, N.

    2002-01-01

    This paper reviews and puts in context some of our recent work on stochastic volatility (SV) modelling for financial economics. Here our main focus is on: (i) the relationship between subordination and SV, (ii) OU based volatility models, (iii) exact option pricing, (iv) realized power variation...

  13. Current status of fluoride volatility method development

    Energy Technology Data Exchange (ETDEWEB)

    Uhlir, J.; Marecek, M.; Skarohlid, J. [UJV - Nuclear Research Institute, Research Centre Rez, CZ-250 68 Husinec - Rez 130 (Czech Republic)

    2013-07-01

    The Fluoride Volatility Method is based on a separation process, which comes out from the specific property of uranium, neptunium and plutonium to form volatile hexafluorides whereas most of fission products (mainly lanthanides) and higher transplutonium elements (americium, curium) present in irradiated fuel form nonvolatile tri-fluorides. Fluoride Volatility Method itself is based on direct fluorination of the spent fuel, but before the fluorination step, the removal of cladding material and subsequent transformation of the fuel into a powdered form with a suitable grain size have to be done. The fluorination is made with fluorine gas in a flame fluorination reactor, where the volatile fluorides (mostly UF{sub 6}) are separated from the non-volatile ones (trivalent minor actinides and majority of fission products). The subsequent operations necessary for partitioning of volatile fluorides are the condensation and evaporation of volatile fluorides, the thermal decomposition of PuF{sub 6} and the finally distillation and sorption used for the purification of uranium product. The Fluoride Volatility Method is considered to be a promising advanced pyrochemical reprocessing technology, which can mainly be used for the reprocessing of oxide spent fuels coming from future GEN IV fast reactors.

  14. Stock market volatility and macroeconomic uncertainty

    NARCIS (Netherlands)

    Arnold, I.J.M.; Vrugt, E.B.

    2006-01-01

    This paper provides empirical evidence on the link between stock market volatility and macroeconomic uncertainty. We show that US stock market volatility is significantly related to the dispersion in economic forecasts from SPF survey participants over the period from 1969 to 1996. This link is much

  15. Fundamental uncertainty and stock market volatility

    NARCIS (Netherlands)

    Arnold, I.J.M.; Vrugt, E.B.

    2008-01-01

    We provide empirical evidence on the link between stock market volatility and macroeconomic uncertainty. We show that US stock market volatility is significantly related to the dispersion in economic forecasts from participants in the Survey of Professional Forecasters over the period 1969 to 1996.

  16. Price volatility in wind dominant electricity markets

    DEFF Research Database (Denmark)

    Farashbashi-Astaneh, Seyed-Mostafa; Chen, Zhe

    2013-01-01

    High penetration of intermittent renewable energy sources causes price volatility in future electricity markets. This is specially the case in European countries that plan high penetration levels. This highlights the necessity for revising market regulations and mechanisms in accordance to genera......High penetration of intermittent renewable energy sources causes price volatility in future electricity markets. This is specially the case in European countries that plan high penetration levels. This highlights the necessity for revising market regulations and mechanisms in accordance...... electricity markets. High price volatility is unappreciated because it imposes high financial risk levels to both electricity consumers and producers. Additionally high price variations impede tracking price signals by consumers in future smart grid and jeopardize implementation of demand response concepts....... The main contribution of this paper is to quantify volatility patterns of electricity price, as penetration level of wind power increases. Results explain a direct relationship between wind penetration and electricity price volatility in a quantitative manner....

  17. Decomposing European bond and equity volatility

    DEFF Research Database (Denmark)

    Christiansen, Charlotte

    The paper investigates volatility spillover from US and aggregate European asset markets into European national asset markets. A main contribution is that bond and equity volatilities are analyzed simultaneously. A new model belonging to the "volatilityspillover" family is suggested......: The conditional variance of e.g. the unexpected German stock return is divided into separate effects from the contemporaneous idiosyncratic variance of US bonds, US stocks, European bonds, European stocks, German bonds, and German stocks. Significant volatility-spillover effects are found. The national bond...... (stock) volatilities are mainly influenced by bond (stock) effects. Global, regional, and local volatility effects are all important. The introduction of the euro is associated with a structural break....

  18. Molecular insights into the local anesthetic receptor within voltage-gated sodium channels using hydroxylated analogues of mexiletine

    Directory of Open Access Journals (Sweden)

    Jean-François eDesaphy

    2012-02-01

    Full Text Available We previously showed that the β-adrenoceptor modulators, clenbuterol and propranolol, directly blocked voltage-gated sodium channels, whereas salbutamol and nadolol did not (Desaphy et al., 2003, suggesting the presence of two hydroxyl groups on the aromatic moiety of the drugs as a molecular requisite for impeding sodium channel block. To verify such an hypothesis, we synthesized five new mexiletine analogues by adding one or two hydroxyl groups to the aryl moiety of the sodium channel blocker and tested these compounds on hNav1.4 channels expressed in HEK293 cells. Concentration-response relationships were constructed using an holding potential of -120 mV at 0.1 Hz (tonic block and 10 Hz (use-dependent block stimulation frequencies. The half-maximum inhibitory concentrations (IC50 were linearly correlated to drug lipophilicity: the less lipophilic the drug, minor was the block. The same compounds were also tested on F1586C and Y1593C hNav1.4 channel mutants, to gain further information on the molecular interactions of mexiletine with its receptor within the sodium channel pore. Alteration of tonic block suggests that the aryl moiety of mexiletine may interact either directly or indirectly with Phe1586 in the closed sodium channel to produce low-affinity binding block, and that this interaction depends on the electrostatic potential of the drug aromatic tail. Alteration of use-dependent block suggests that addition of hydroxyl groups to the aryl moiety may modify high-affinity binding of the drug ammine terminal to Phe1586 through cooperativity between the two pharmacophores, this effect being mainly related to drug lipophilicity. Mutation of Tyr1593 further impaired such cooperativity. In conclusion, these results confirm our former hypothesis showing that the presence of hydroxyl groups to the aryl moiety of mexiletine greatly reduced sodium channel block, and provide molecular insights into the intimate interaction of local anesthetics with

  19. Anesthetic management of a patient with stiff-person syndrome and thymoma: a case report

    Institute of Scientific and Technical Information of China (English)

    QIN Xiang; WANG Dong-xin; WU Xin-min

    2006-01-01

    @@ Stiff-person syndrome (SPS, also called stiff-man syndrome) is a rare neurological disease with autoimmune features. It is characterized by fluctuating and progressive muscle rigidity, and episodic spasm that prominently involve axial and limb musculature.1,2 Herein we report a case of anesthetic management of a patient with SPS for thymectomy and review several other cases.

  20. Evaluation of transpulmonary thermodilution as a method to measure cardiac output in anesthetized cats.

    Science.gov (United States)

    Beaulieu, Kim E; Kerr, Carolyn L; McDonell, Wayne N

    2009-01-01

    The objectives of this study were to evaluate the use of a transpulmonary thermodilution (Trans) technique for the measurement of cardiac output, and to determine the agreement between Trans and conventional thermodilution (TD) in anesthetized cats. Using each technique, cardiac output was measured in 5 mature cats (weights 2.4 to 5.6 kg) anesthetized with isoflurane. To induce different levels of cardiac output in each cat, anesthesia was maintained at > 1.5x end-tidal minimum alveolar concentration (MAC) of isoflurane, and at 1.3x end-tidal isoflurane MAC with and without administration of dobutamine. At least 2 comparisons between TD and Trans values were made at each cardiac output rate. Thirty-two of the 42 recorded comparisons were analyzed. Linear regression analysis (TD vs Trans) yielded an r(2) value of 0.83. The mean bias (TD-Trans) was -3.7 mL/kg/min with limits of agreement of -35.9 to 28.5 mL/kg/min. The concordance coefficient was 0.91. The Trans method showed good relationship and good agreement with TD in anesthetized cats. The Trans method is a relatively noninvasive, practical, and safe method to measure cardiac output in anesthetized cats.

  1. Heart rate effects of intraosseous injections using slow and fast rates of anesthetic solution deposition.

    Science.gov (United States)

    Susi, Louis; Reader, Al; Nusstein, John; Beck, Mike; Weaver, Joel; Drum, Melissa

    2008-01-01

    The authors, using a crossover design, randomly administered, in a single-blind manner, 3 primary intraosseous injections to 61 subjects using: the Wand local anesthetic system at a deposition rate of 45 seconds (fast injection); the Wand local anesthetic system at a deposition rate of 4 minutes and 45 seconds (slow injection); a conventional syringe injection at a deposition rate of 4 minutes and 45 seconds (slow injection), in 3 separate appointments spaced at least 3 weeks apart. A pulse oximeter measured heart rate (pulse). The results demonstrated the mean maximum heart rate was statistically higher with the fast intraosseous injection (average 21 to 28 beats/min increase) than either of the 2 slow intraosseous injections (average 10 to 12 beats/min increase). There was no statistically significant difference between the 2 slow injections. We concluded that an intraosseous injection of 1.4 mL of 2% lidocaine with 1 : 100,000 epinephrine with the Wand at a 45-second rate of anesthetic deposition resulted in a significantly higher heart rate when compared with a 4-minute and 45-second anesthetic solution deposition using either the Wand or traditional syringe.

  2. 静脉麻醉药的研究进展%Research progress of intravenous anesthetics

    Institute of Scientific and Technical Information of China (English)

    浦鹏飞

    2012-01-01

    Intravenous anesthetics is classified into the barbiturates and non-barbiturates. Although great progress has been made in the intravenous anesthetic pharmacokinetic-pharmacodynamic knowledge and intravenous anesthesia, no intravenous anesthetics at the present is considered to be ideal in all respects. Therefore, it is still urgent to find approaches to create an ideal anesthetic state, which is secure, smooth and easy to control.%静脉麻醉药主要分为巴比妥类药物和非巴比妥类药物,虽然静脉麻醉药药代动力学-药效学知识和静脉麻醉技术均取得了长足进步,但目前还无一种在各方面都十分理想的静脉麻醉药,所以实现安全、易控、平稳和苏醒迅速的理想麻醉状态仍是摆在我们面前最严峻的问题.

  3. Trigeminal nerve injury associated with injection of local anesthetics: needle lesion or neurotoxicity?

    DEFF Research Database (Denmark)

    Hillerup, Søren; Jensen, Rigmor H; Ersbøll, Bjarne Kjær

    2011-01-01

    BACKGROUND: The authors used comprehensive national registry and clinical data to conduct a study of adverse drug reactions (ADRs), in particular neurosensory disturbance (NSD), associated with local anesthetics used in dentistry METHODS: The study included data sets of annual sales of local anes...

  4. Memory-impairing effects of local anesthetics in an elevated plus-maze test in mice

    Directory of Open Access Journals (Sweden)

    S.L. Blatt

    1998-04-01

    Full Text Available Post-training intracerebroventricular administration of procaine (20 µg/µl and dimethocaine (10 or 20 µg/µl, local anesthetics of the ester class, prolonged the latency (s in the retention test of male and female 3-month-old Swiss albino mice (25-35 g body weight; N = 140 in the elevated plus-maze (mean ± SEM for 10 male mice: control = 41.2 ± 8.1; procaine = 78.5 ± 10.3; 10 µg/µl dimethocaine = 58.7 ± 12.3; 20 µg/µl dimethocaine = 109.6 ± 5.73; for 10 female mice: control = 34.8 ± 5.8; procaine = 55.3 ± 13.4; 10 µg/µl dimethocaine = 59.9 ± 12.3 and 20 µg/µl dimethocaine = 61.3 ± 11.1. However, lidocaine (10 or 20 µg/µl, an amide class type of local anesthetic, failed to influence this parameter. Local anesthetics at the dose range used did not affect the motor coordination of mice exposed to the rota-rod test. These results suggest that procaine and dimethocaine impair some memory process(es in the plus-maze test. These findings are interpreted in terms of non-anesthetic mechanisms of action of these drugs on memory impairment and also confirm the validity of the elevated plus-maze for the evaluation of drugs affecting learning and memory in mice

  5. Dexmedetomidine as an adjuvant to local anesthetics in brachial plexus blocks

    Science.gov (United States)

    Ping, Yongmei; Ye, Qigang; Wang, Wenwei; Ye, Pingke; You, Zhibin

    2017-01-01

    Abstract Background: Brachial plexus block (BPB) for upper extremity surgery provides superior analgesia, but this advantage is limited by the pharmacological duration of local anesthetics. Dexmedetomidine (DEX) as a local anesthetics adjuvant for BPB has been utilized to prolong the duration of the nerve block in some randomized controlled trials (RCTs) but is far from unanimous in the efficacy and safety of the perineural route. Hence, an updated meta-analysis was conducted to assess the efficacy and safety of DEX as local anesthetic adjuvants on BPB. Methods: A search in electronic databases was conducted to collect the RCTs that investigated the impact of adding DEX to local anesthetics for BPB. Sensory block duration, motor block duration, onset time of sensory and motor block, time to first analgesic request, the common adverse effects were analyzed. Results: Eighteen trails (1014 patients) were included with 515 patients receiving perineural DEX. The addition of DEX prolonged the duration of sensory block (WMD 257 minutes, 95%CI 191.79–322.24, P administration of DEX. PMID:28121930

  6. Child with Saethre-Chotzen syndrome: anesthetic management and literature review.

    Science.gov (United States)

    Sharma, A; Patel, N; Arora, S; Ramachandran, R

    2014-01-01

    Saethre-Chotzen syndrome (SCS) is a type of acro-cephalo-syndactyly (ACS) syndrome, characterized by premature fusion of the coronal sutures, facial dysmorphism, syndactyly, skeletal deformity, and congenital heart malformations. We here describe a child with diagnosed SCS, who underwent squint surgery under general anesthesia, and review the anesthetic concerns thereof.

  7. Evaluation of the aesthetics of physical methods of euthanasia of anesthetized rats.

    Science.gov (United States)

    Hickman, Debra L; Johnson, Steven W

    2011-09-01

    Dissection of living brain tissue for in vitro experiments requires the use of a rapid euthanasia method. However, the method must not subject animals to unnecessary pain and must be aesthetically acceptable to experimenters. The purposes of the current study were to assess the aesthetics of 6 euthanasia methods, measure the procedure duration, and evaluate brain for pathology after each procedure. We digitally recorded euthanasia of isoflurane-anesthetized rats by 6 physical methods: anesthetic overdose, cardiac exsanguination, decapitation, closed intrathoracic transection of the great vessels and heart, thoracic percussion, and thoracotomy with rupture of great vessels. Volunteer researchers and animal caretakers watched the video and completed an associated questionnaire. Anesthetic overdose and cardiac exsanguinations were rated most aesthetically pleasing, although these procedures took the longest to complete. In contrast, decapitation and thoracic percussion were the least aesthetically pleasing, but these methods were the quickest. No demographic factor was identified that could predict whether a given euthanasia procedure would be favored for aesthetic reasons, and participants provided a wide variety of rationales for the aesthetic ratings they assigned. Although all of these euthanasia methods meet the criteria of approved methods of euthanasia of anesthetized rats as defined by the AVMA, aesthetic features and the scientific need for rapid euthanasia are both considerations in selecting a method.

  8. Popliteal pterygium syndrome (PPS) with intra-alveolar syngnathia: a discussion of anesthetic and surgical considerations.

    Science.gov (United States)

    Gahm, Caroline; Kuylenstierna, Richard; Papatziamos, Georgios

    2007-10-01

    Popliteal pterygium syndrome (PPS) is a rare genetic disorder that involves the association of a popliteal web with a combination of craniofacial, genitourinary and extremity malformations. In this article, we describe a patient with PPS complicated with multiple intra-alveolar syngnathia. We discuss the anesthetic and the surgical management of this case and review the literature regarding PPS and intra-alveolar syngnathia.

  9. What is the optimal anesthetic protocol for measurements of cerebral autoregulation in spontaneously breathing mice?

    Science.gov (United States)

    Wang, Zhenghui; Schuler, Beat; Vogel, Olga; Arras, Margarete; Vogel, Johannes

    2010-12-01

    Autoregulation, an important feature of the cerebral circulation, is affected in many diseases. Since genetically modified mice are a fundamental tool in biomedical research, including neuro(bio)logy also in this specie measurements of cerebral autoregulation (CA) are mandatory. However, this requires anesthesia that unfortunately significantly impacts cerebral perfusion and consequently might distort CA measurements directly or by altering arterial pCO(2). The latter can be avoided by artificial ventilation but requires several control measurements of blood gases, each consuming at least 100 μl of blood or 5% of a mouse's blood volume. To avoid such diagnostic hemorrhage, we systematically analyzed the effect of different common anesthetic protocols used for rodents in spontaneously breathing mice on CA measured with Laser speckle perfusion imaging. Halothane, Isoflurane and Pentobarbital abrogated CA and Ketamin/Xylazine as well as Chloralose had a moderate reproducibility. In contrast, the rather rarely used anesthetic Ethomidate applied in low doses combined with local anesthetics had the best reproducibility. Although with this anesthesia the lower CA limit was lower than with Ketamin/Xylazine and Chloralose as reported in the handful of papers so far dealing with CA in mice, we suggest Ethomidate as the anesthetic of choice for CA measurements in spontaneously breathing mice.

  10. An Anesthetic Drug Demonstration and an Introductory Antioxidant Activity Experiment with "Eugene, the Sleepy Fish"

    Science.gov (United States)

    Barcena, Homar; Chen, Peishan

    2016-01-01

    Students are introduced to spectrophotometry in comparing the antioxidant activity of pure eugenol and oil of cloves from a commercial source using a modified ferric reducing antioxidant power (FRAP) assay. The extraction of the essential oil from dried cloves is demonstrated to facilitate discussions on green chemistry. The anesthetic properties…

  11. Noxious Stimulation Response Index A Novel Anesthetic State Index Based on Hypnotic-Opioid Interaction

    NARCIS (Netherlands)

    Luginbuehl, Martin; Schumacher, Peter M.; Vuilleumier, Pascal; Vereecke, Hugo; Heyse, Bjoern; Bouillon, Thomas W.; Struys, Michel M. R. F.

    2010-01-01

    Background: The noxious stimulation response index (NSRI) is a novel anesthetic depth index ranging between 100 and 0, computed from hypnotic and opioid effect-site concentrations using a hierarchical interaction model. The authors validated the NSRI on previously published data. Methods: The data e

  12. Comparative analysis of assessment methods for operational and anesthetic risks in ulcerative gastroduodenal bleeding

    Directory of Open Access Journals (Sweden)

    Potakhin S.N.

    2015-09-01

    Full Text Available Aim of the investigation: to conduct a comparative analysis of methods of evaluation of surgical and anesthetic risks in ulcerative gastroduodenal bleeding. Materials and methods. A retrospective analysis ofthe extent of the surgical and anesthetic risks and results of treatment of 71 patients with peptic ulcer bleeding has been conducted in the study. To evaluate the surgical and anesthetic risks classification trees are used, scale ТА. Rockall and prognosis System of rebleeding (SPRK, proposed by N. V. Lebedev et al. in 2009, enabling to evaluate the probability of a fatal outcome. To compare the efficacy ofthe methods the following indicators are used: sensitivity, specificity and prediction of positive result. Results. The study compared the results ofthe risk assessment emergency operation by using these methods with the outcome ofthe operation. The comparison ofthe prognosis results in sensitivity leads to the conclusion that the scales ТА. Rockall and SPRK are worse than the developed method of classification trees in recognizing patients with poor outcome of surgery. Conclusion. The method of classification trees can be considered as the most accurate method of evaluation of surgical and anesthetic risks in ulcerative gastroduodenal bleeding.

  13. Anesthetic exposure and health of dental personnel, 1 June 1978-30 November 1980

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, E.N.

    1980-01-01

    An epidemiologic survey was conducted to determine possible health hazards in the dental profession, with particular attention being given to the results of exposure to anesthetic gases. The survey contacted 30,650 dentists and 30,547 chairside assistants who were subsequently grouped according to exposure to inhalation anesthetics in the dental operatory during the course of their employment experience. An increase in liver disease 1.7 above that expected was noted in male dentists heavily exposed to anesthetics, combined with a 1.2 fold increase for kidney disease and 1.9-fold increase for neurological disease. The spontaneous abortion rate in wives of male dentists was 1.5-fold higher than expected. Occupational exposure to anesthetics, either direct or indirect, was associated with significant increases in spontaneous abortion over control levels during the first and second trimester of pregnancy. Women who smoked during pregnancy showed increased risk of spontaneous abortion, with a 27% increase occurring in dental assistants and a 21% increase in wives of dentists. A 34% increased risk of babies having congenital abnormalities was noted among smoking dental assistants.

  14. Left atrial ball thrombus with acute mesenteric ischemia: Anesthetic management and role of transesophageal echocardiography

    Directory of Open Access Journals (Sweden)

    Neeti Makhija

    2014-01-01

    Full Text Available A 62 year old female with severe mitral stenosis, large left atrial ball thrombus and acute mesenteric ischemia emergently underwent mitral valve replacement, left atrial clot removal and emergency laparotomy for mesenteric ischemia. Peri-operative management issues, particularly, the anesthetic challenges and the role of transesophageal echocardiography are discussed.

  15. Risk of acquired methemoglobinemia with different topical anesthetics during endoscopic procedures

    Directory of Open Access Journals (Sweden)

    Vallurupalli S

    2011-07-01

    Full Text Available Srikanth Vallurupalli1, Shalini Manchanda21Division of General Internal Medicine, Department of Medicine, Southern Illinois University School of Medicine, Springfield, IL, USA; 2Division of Pulmonary, Allergy, Critical Care, and Occupational Medicine, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USAIntroduction: Methemoglobinemia is a recognized complication of the use of topical anesthetic sprays. The true scope of the problem or the risk with different topical anesthetic sprays and endoscopic procedures is unknown.Methods: We retrospectively identified all cases of methemoglobinemia that occurred in a university affiliated community hospital from 2001 to 2007.Results: Eleven cases of methemoglobinemia were identified over the 6-year period. Nine (82% occurred with use of benzocaine spray during transesophageal echocardiography (TEE. Patients who developed methemoglobinemia secondary to the topical anesthetic spray compared to other causes were more likely to be older, have lower mean hemoglobin levels (10.5 ± 0.5 g/dL vs 11.3 ± 0.0 g/dL, and a higher mean methemoglobin concentration at diagnosis (40.8% ± 5.2% vs 24% ± 10%. However, only age reached statistical significance (P = 0.004.Conclusion: In a university-affiliated community hospital, topical anesthetic sprays account for most of the burden of methemoglobinemia. Benzocaine use in the context of TEE caused more methemoglobinemia compared to lidocaine and other endoscopic procedures. This observation supports previous data and findings deserve further study.Keywords: methemoglobinemia, benzocaine, lidocaine, transesophageal echocardiography, endoscopy

  16. Evaluation of prilocaine for the reduction of pain associated with transmucosal anesthetic administration.

    Science.gov (United States)

    Kramp, L. F.; Eleazer, P. D.; Scheetz, J. P.

    1999-01-01

    This investigation evaluated the use and efficacy of prilocaine HCl (4% plain Citanest) for minimizing pain associated with the intraoral administration of local anesthesia. Clinical anecdotes support the hypothesis that prilocaine without a vasoconstrictor reduces pain during injection. To determine relative injection discomfort, use of 4% plain prilocaine was compared with use of 2% lidocaine with 1:100,000 epinephrine and 2% mepivacaine with 1:20,000 levonordefrin. Prior to routine endodontic procedures, 150 adult patients received 0.3 to 1.8 mL of local anesthetic via the same gauge needle without the use of a topical local anesthetic. Injection methods included buccal infiltration, labial infiltration, palatal infiltration, and inferior alveolar nerve block. Following each injection, patients were asked to describe the level of discomfort by scoring on a visual analog scale of 1 to 10, where 1 = painless and 10 = severe pain. Analyses via 2-way analysis of variance revealed no interaction between anesthetic and site of injection. However, there were statistically significant differences among the injection sites. Post hoc analysis revealed that prilocaine was associated with significantly less pain perception when compared to mepivacaine and lidocaine. These results suggest that differences in initial pain perception during transmucosal injection may be a function of the local anesthetic use, and prilocaine can produce less discomfort than the others tested. Images Figure 1 PMID:10853565

  17. Are one or two dangerous? Lidocaine and topical anesthetic exposures in children.

    Science.gov (United States)

    Curtis, Liesl A; Dolan, Teresa Sullivan; Seibert, H Edward

    2009-07-01

    Topical anesthetics are found in a variety of prescription and non-prescription preparations, from teething gels to hemorrhoid creams. In 2003, there were 8576 exposures to local/topical anesthetics reported to the American Association of Poison Control Centers, with 67% of cases in the age group younger than 6 years old. This report reviews the available literature involving topical anesthetic exposures in children younger than 6 years old, including the National Library of Medicine's Pub Med database (limited to English language) and data from POISINDEX. Additionally, we reviewed the American Association of Poison Control Centers' annual reports from 1983 to 2003. There were 7 deaths in this age range from topical anesthetics. Although the number of deaths is low, the fact that there have been deaths reveals the serious nature of the toxicity that can result from these readily available non-prescription analgesics. Toxicity may result from topical absorption, ingestion, or aspiration. Additionally, toxicity can result from unintentional as well as therapeutic mishaps. Although the number of cases is limited, these medications can be toxic at low doses-which, in children younger than 6 years of age, may amount to as little as a teaspoon.

  18. Implications of Climate Volatility for Agricultural Commodity Markets in the Presence of Biofuel Mandates

    Science.gov (United States)

    Verma, M.; Diffenbaugh, N. S.; Hertel, T. W.; Beckman, J.

    2011-12-01

    In presence of bio-fuels, link between energy and agricultural commodity markets has become more complex. An increase in ethanol production to minimum 15bn gallons a year - Renewable Fuel Standard (RFS) and current technically permissible maximum 10% blending limit - Blend Wall (BW); make the link even stronger. If oil prices in future do not rise significantly from their current levels, this minimum production requirement would likely be binding. In such a scenario any fluctuation in crop production will have to be absorbed by the non-ethanol usage of the crop and would translate into crop prices adjusting to clear the markets and therefore the commodity prices will be more volatile. At high oil prices it is possible that the BW may become binding, severing the link between oil prices and commodity prices as well, potentially leading to higher price volatility. Hertel and Beckman (2010) find that, with both RFS and BW simultaneously binding, corn price volatility due to supply side shocks (which could arise from extreme climate events) could be more than 50% as large as in the absence of bio-fuel policies. So energy markets are important determinants of agricultural commodity price volatility. This proposal intends to introduce the increased supply side volatility on account of climate change and volatility, in the framework. Global warming on account of increased GHG concentrations is expected to increase the intensity and frequency of hot extremes in US (Diffenbaugh et al. 2008) and therefore affect corn yields. With supply shocks expected to increase, binding RFS and BW will exacerbate the volatility, while if they are non-binding then the price changes could be cushioned. We propose to model the impacts of climate changes and volatility on commodity prices by linking three main components - a. Projections for change in temperature and precipitation using climate model b. A statistical model to predict impacts of change in climate variable on corn yields in US

  19. Gas-liquid partitioning of halogenated volatile organic compounds in aqueous cyclodextrin solutions

    Energy Technology Data Exchange (ETDEWEB)

    Ondo, Daniel; Barankova, Eva [Department of Physical Chemistry, Institute of Chemical Technology, Technicka 5, 166 28 Prague 6 (Czech Republic); Dohnal, Vladimir, E-mail: dohnalv@vscht.cz [Department of Physical Chemistry, Institute of Chemical Technology, Technicka 5, 166 28 Prague 6 (Czech Republic)

    2011-08-15

    Highlights: > Binding of halogenated VOCs with cyclodextrins examined through g-l partitioning. > Complex stabilities reflect host-guest size matching and hydrophobic interaction. > Presence of halogens in the guest molecule stabilizes the binding. > Thermodynamic origin of the binding varies greatly among the systems studied. > Results obey the guest-CD global enthalpy-entropy compensation relationship. - Abstract: Gas-liquid partitioning coefficients (K{sub GL}) were measured for halogenated volatile organic compounds (VOCs), namely 1-chlorobutane, methoxyflurane, pentafluoropropan-1-ol, heptafluorobutan-1-ol, {alpha},{alpha},{alpha}-trifluorotoluene, and toluene in aqueous solutions of natural {alpha}-, {beta}-, and {gamma}-cyclodextrins (CDs) at temperatures from (273.35 to 326.35) K employing the techniques of headspace gas chromatography and inert gas stripping. The binding constants of the 1:1 inclusion complex formation between the VOCs and CDs were evaluated from the depression of the VOCs volatility as a function of CD concentration. The host-guest size matching and the hydrophobic interaction concept were used to rationalize the observed widely different affinity of the VOC-CD pairs to form the inclusion complex. The enthalpic and entropic component of the standard Gibbs free energy of complex formation as derived from the temperature dependence of the binding constant indicate the thermodynamic origin of the binding to vary greatly among the systems studied, but follow the global enthalpy-entropy compensation relationships reported previously in the literature.

  20. Impact of hyaluronidase on anesthetic distribution in retrobulbar region following sub-Tenon anesthesia

    Directory of Open Access Journals (Sweden)

    Šurbatović Maja

    2008-01-01

    Full Text Available Background/Aim. Sub-Tenon's block is nowadays commonly used in ophthalmic surgery because of its safety and efficacy. The aim of this study was to investigate the distribution of the anesthetic solution with different amounts of hyaluronidase in the retrobulbar space, following an injection into the Sub-Tenon's space. Methods. In this experimental study, 40 pig cadaver heads were used (80 eyeballs. The material was divided into four groups (of 20 eyeballs each. Each group was administered 4.5 ml of a mixture of 2% lignocaine, 0.5% bupivacaine, and 0.5 ml of Indian ink, with different amounts of hyaluronidase - 15 IU/ml, 75 IU/ml, 150 IU/ml, except the control one. Samples of retrobulbar tissue were analyzed using the standard histopathological procedure. After that, they were also analyzed using the Adobe Photoshop program® (Windows, USA. The retrobulbar space was divided into eight zones by four perpendicular lines, which crossed in the centre of the optic nerve. The presence of ink in fat and muscle tissues and in the sheath of the optic nerve was observed. Results. The presence of the local anesthetic solution was significantly higher in inferonasal and superonasal quadrants of the fat and muscle tissues (p < 0.01. The distribution in optic nerve sheath is similar in each quadrant. Distribution of local anesthetic in each zone of the muscle tissue (I-VIII was strongly influenced by the amount of hyaluronidase added. In the fat tissue, the distribution of local anesthetic under the influence of hyaluronidase was significantly higher (p < 0.05 in the areas which were distant from the place of injection (I-IV. The distribution in the optic nerve sheath is significantly higher (p < 0.01 in the group with 150 IU/ml of hyaluronidase. Conclusions. Following a sub-Tenon block local anesthetic was present in the retrobulbar space in a high percentage of the cases. The presence of local anesthetic solution in retrobulbar space depends on the amount of

  1. General anesthetics inhibit LPS-induced IL-1β expression in glial cells.

    Directory of Open Access Journals (Sweden)

    Tomoharu Tanaka

    Full Text Available BACKGROUND: Glial cells, including microglia and astrocytes, are considered the primary source of proinflammatory cytokines in the brain. Immune insults stimulate glial cells to secrete proinflammatory cytokines that modulate the acute systemic response, which includes fever, behavioral changes, and hypothalamic-pituitary-adrenal (HPA axis activation. We investigated the effect of general anesthetics on proinflammatory cytokine expression in the primary cultured glial cells, the microglial cell line BV-2, the astrocytic cell line A-1 and mouse brain. METHODOLOGY/PRINCIPAL FINDINGS: Primary cultured glial cells were exposed to lipopolysaccharide (LPS in combination with general anesthetics including isoflurane, pentobarbital, midazolam, ketamine, and propofol. Following this treatment, we examined glial cell expression of the proinflammatory cytokines interleukin (IL-1β, IL-6, and tumor necrosis factor-alpha (TNF-α. LPS-induced expression of IL-1β mRNA and protein were significantly reduced by all the anesthetics tested, whereas IL-6 and TNF-α mRNA expression was unaffected. The anesthetics suppressed LPS-induced extracellular signal-regulated kinase 1/2 (ERK 1/2 phosphorylation, but did not affect nuclear factor-kappaB and activator protein-1 activation. The same effect was observed with BV-2, but not with A-1 cells. In the mouse experiments, LPS was injected intraperitoneally, and isoflurane suppressed IL-1β in the brain and adrenocorticotropic hormone in plasma, but not IL-1β in plasma. CONCLUSIONS/SIGNIFICANCE: Taken together, our results indicate that general anesthetics inhibit LPS-induced IL-1β upregulation in glial cells, particularly microglia, and affects HPA axis participation in the stress response.

  2. Flower volatiles, crop varieties and bee responses.

    Directory of Open Access Journals (Sweden)

    Björn K Klatt

    Full Text Available Pollination contributes to an estimated one third of global food production, through both the improvement of the yield and the quality of crops. Volatile compounds emitted by crop flowers mediate plant-pollinator interactions, but differences between crop varieties are still little explored. We investigated whether the visitation of crop flowers is determined by variety-specific flower volatiles using strawberry varieties (Fragaria x ananassa Duchesne and how this affects the pollination services of the wild bee Osmia bicornis L. Flower volatile compounds of three strawberry varieties were measured via headspace collection. Gas chromatography showed that the three strawberry varieties produced the same volatile compounds but with quantitative differences of the total amount of volatiles and between distinct compounds. Electroantennographic recordings showed that inexperienced females of Osmia bicornis had higher antennal responses to all volatile compounds than to controls of air and paraffin oil, however responses differed between compounds. The variety Sonata was found to emit a total higher level of volatiles and also higher levels of most of the compounds that evoked antennal responses compared with the other varieties Honeoye and Darselect. Sonata also received more flower visits from Osmia bicornis females under field conditions, compared with Honeoye. Our results suggest that differences in the emission of flower volatile compounds among strawberry varieties mediate their attractiveness to females of Osmia bicornis. Since quality and quantity of marketable fruits depend on optimal pollination, a better understanding of the role of flower volatiles in crop production is required and should be considered more closely in crop-variety breeding.

  3. Volatility Forecast in Crises and Expansions

    Directory of Open Access Journals (Sweden)

    Sergii Pypko

    2015-08-01

    Full Text Available We build a discrete-time non-linear model for volatility forecasting purposes. This model belongs to the class of threshold-autoregressive models, where changes in regimes are governed by past returns. The ability to capture changes in volatility regimes and using more accurate volatility measures allow outperforming other benchmark models, such as linear heterogeneous autoregressive model and GARCH specifications. Finally, we show how to derive closed-form expression for multiple-step-ahead forecasting by exploiting information about the conditional distribution of returns.

  4. Modelling of volatility in monetary transmission mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Dobešová, Anna; Klepáč, Václav; Kolman, Pavel [Department of Statistics and Operation Analysis, Faculty of Business and Economics, Mendel University in Brno, Zemědělská 1, 61300, Brno (Czech Republic); Bednářová, Petra [Institute of Technology and Business, Okružní 517/10, 370 01, České Budějovice (Czech Republic)

    2015-03-10

    The aim of this paper is to compare different approaches to modeling of volatility in monetary transmission mechanism. For this purpose we built time-varying parameter VAR (TVP-VAR) model with stochastic volatility and VAR-DCC-GARCH model with conditional variance. The data from three European countries are included in the analysis: the Czech Republic, Germany and Slovakia. Results show that VAR-DCC-GARCH system captures higher volatility of observed variables but main trends and detected breaks are generally identical in both approaches.

  5. Does Energy Consumption Volatility Affect Real GDP Volatility? An Empirical Analysis for the UK

    OpenAIRE

    Abdul Rashid; Ozge Kandemir Kocaaslan

    2013-01-01

    This paper empirically examines the relation between energy consumption volatility and unpredictable variations in real gross domestic product (GDP) in the UK. Estimating the Markov switching ARCH model we find a significant regime switching in the behavior of both energy consumption and GDP volatility. The results from the Markov regime-switching model show that the variability of energy consumption has a significant role to play in determining the behavior of GDP volatilities. Moreover, the...

  6. Lunar In-Situ Volatile Extraction Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A method of extracting volatile resources from the Lunar regolith is proposed to reduce the launch mass and cost of bringing such resources from the Earth to enable...

  7. Volatile profile of wine Teran PTP

    Directory of Open Access Journals (Sweden)

    Helena BAŠA ČESNIK

    2015-11-01

    Full Text Available Teran PTP is a protected wine with a recognized traditional denomination produced from a grapevine variety ‘Refošk’ in winegrowing district Kras in Slovenia (European Union, 2009; Pravilnik, 2008. The aromatic profile of 82 Teran PTP wines produced in years 2011, 2012 and 2013 was monitored. Intotal the content of 16 volatile compounds was determined. The volatile compounds from wine were extracted following the liquid-liquid extraction and determined with a GC-MS method. The odour activity values and relative odour contributions were calculated for each volatile compound identified. Among sensorial important volatiles the highest odour activity values were determined for ethyl octanoate, ethyl hexanoate, isoamyl acetate and ethyl butyrate. Other research papers also showed, that all red wines investigated except one contained ethyl octanoate, ethyl hexanoate, isoamyl acetate and ethyl butyrate above sensory thresholds.

  8. Volatility and the natural resource curse

    NARCIS (Netherlands)

    van der Ploeg, F.; Poelhekke, S.

    2009-01-01

    We provide cross-country evidence that rejects the traditional interpretation of the natural resource curse. First, growth depends negatively on volatility of unanticipated output growth independent of initial income, investment, human capital, trade openness, natural resource dependence, and popula

  9. Assessing relative volatility/intermittency/energy dissipation

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole E.; Pakkanen, Mikko S.; Schmiegel, Jürgen

    2014-01-01

    We introduce the notion of relative volatility/intermittency and demonstrate how relative volatility statistics can be used to estimate consistently the temporal variation of volatility/intermittency when the data of interest are generated by a non-semimartingale, or a Brownian semistationary...... process in particular. This estimation method is motivated by the assessment of relative energy dissipation in empirical data of turbulence, but it is also applicable in other areas. We develop a probabilistic asymptotic theory for realised relative power variations of Brownian semistationary processes......, and introduce inference methods based on the theory. We also discuss how to extend the asymptotic theory to other classes of processes exhibiting stochastic volatility/intermittency. As an empirical application, we study relative energy dissipation in data of atmospheric turbulence....

  10. Analyzing binding data.

    Science.gov (United States)

    Motulsky, Harvey J; Neubig, Richard R

    2010-07-01

    Measuring the rate and extent of radioligand binding provides information on the number of binding sites, and their affinity and accessibility of these binding sites for various drugs. This unit explains how to design and analyze such experiments.

  11. Cyclodextrin-based microsensors for volatile organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, B.; Johnson, S.; Shi, J.; Yang, Xiaoguang

    1997-10-01

    Host-guest chemistry and self-assembly techniques are being explored to develop species selective thin-films for real-time sensing of volatile organic compounds (VOCs). Cyclodextrin (CD) and calixarene (CA) molecules are known to form guest-host inclusion complexes with a variety of organic molecules. Through the control of the cavity size and chemical functionality on the rims of these bucket-like molecules, the binding affinities for formation of inclusion complexes can be controlled and optimized for specific agents. Self-assembly techniques are used to covalently bond these reagent molecules to the surface of acoustic transducers to create dense, highly oriented, and stable thin films. Self-assembly techniques have also been used to fabricate multilayer thin film containing molecular recognition reagents through alternating adsorption of charged species in aqueous solutions. Self-assembly of polymeric molecules of the SAW device was also explored for fabricating species selective interfaces.

  12. Effects of Halogenated Inhalation Anesthetics on Learning and Memory Function and Central Neurotransmitter Systems in Developing Brain%卤代吸入麻醉药对发育期大脑学习记忆功能及中枢神经递质受体系统的影响

    Institute of Scientific and Technical Information of China (English)

    唐冬梅

    2012-01-01

    New halogenated inhalation anesthetics such as sevoflurane and isoflurane have significant advantages in pediatric clinical anesthesia due to their features of high-performance,good controllability,and less respiratory tract irritation. Infant nervous system has high plasticity, so alogenated inhalation anesthetics could cause degenerative changes in the immature brain neurons, even the continuous delay in learning and memory impairment. So far,the mechanisms of volatile anesthetics affecting the cognitive function of developing brain is not conclusive.%新型卤代吸入麻醉药(如七氟烷、异氟烷等)因具有麻醉效能高、可控性强、呼吸道刺激小等特点,在小儿临床麻醉中具有显著优势.婴幼儿神经系统具有较高的可塑性,因此吸入麻醉药可能更易造成未成熟大脑神经元退行性改变,甚至延迟的持续性学习记忆功能损害.目前关于吸入麻醉药影响发育期大脑认知功能的具体机制尚未定论.

  13. Ammonia volatilization from sows on grassland

    Science.gov (United States)

    Sommer, S. G.; Søgaard, H. T.; Møller, H. B.; Morsing, S.

    According to regulations, sows with piglets on organic farms must graze on pastures. Volatilization of ammonia (NH 3) from urine patches may represent a significant source of nitrogen (N) loss from these farms. Inputs of N are low on organic farms and losses may reduce crop production. This study examined spatial variations in NH 3 volatilization using a movable dynamic chamber, and the pH and total ammoniacal nitrogen (TAN) content in the topsoil of pastures with grazing sows was measured during five periods between June 1998 and May 1999. Gross NH 3 volatilization from the pastures was also measured with an atmospheric mass balance technique during seven periods from September 1997 until June 1999. The dynamic chamber study showed a high variation in NH 3 volatilization because of the distribution of urine; losses were between 0 and 2.8 g NH 3-N m -2 day -1. Volatilization was highest near the feeding area and the huts, where the sows tended to urinate. Ammonia volatilization rate was linearly related to the product of NH 3 concentration in the boundary layer and wind speed. The NH 3 in the boundary layer was in equilibrium with NH 3 in soil solution. Gross NH 3 volatilization was in the range 0.07-2.1 kg NH 3-N ha -1 day -1 from a pasture with 24 sows ha -1. Ammonia volatilization was related to the amount of feed given to the sows, incident solar radiation and air temperature during measuring periods, and also to temperature, incident solar radiation and rain 1-2 days before measurements. Annual ammonia loss was 4.8 kg NH 3-N sow -1.

  14. Anticipating Long-Term Stock Market Volatility

    OpenAIRE

    Conrad, Christian; Loch, Karin

    2012-01-01

    We investigate the relationship between long-term U.S. stock market risks and the macroeconomic environment using a two component GARCH-MIDAS model. Our results provide strong evidence in favor of counter-cyclical behavior of long-term stock market volatility. Among the various macro variables in our dataset the term spread, housing starts, corporate profits and the unemployment rate have the highest predictive ability for stock market volatility . While the term spread and housing starts are...

  15. Financial Development, Financial Structure, and Macroeconomic Volatility: Evidence from China

    Directory of Open Access Journals (Sweden)

    Feng Wei

    2016-11-01

    Full Text Available Using annual data from 1997–2014 of 30 provinces, municipalities, and autonomous regions, subdividing trended and cyclical volatility of macroeconomics and inflation, considering different indicators of financial development and financial structure, this paper investigated the impact of financial development and financial structure on macroeconomic volatility. The empirical results found that (1 the trended and cyclical volatility of the previous macroeconomic period had a significantly positive impact on that of the current period, and the impact of trended volatility was greater than that of cyclical volatility; (2 financial development had a significantly negative impact on macroeconomic cyclical volatility through inflation cyclical volatility, but inflation trended volatility would amplify macroeconomic volatility; financial markets have no significant effect on macroeconomic volatility; financial structure measured with the ratio of stock market turnover and the efficiency of the financial development had a significant positive impact on macroeconomic cyclical volatility; and (3 inflation trended volatility had a significantly negative impact on macroeconomic cyclical volatility and trended volatility, while inflation cyclical volatility had a significantly positive impact on macroeconomic cyclical volatility.

  16. Long memory and tail dependence in trading volume and volatility

    DEFF Research Database (Denmark)

    Rossi, Eduardo; Santucci de Magistris, Paolo

    2013-01-01

    We investigate the relationship between volatility, measured by realized volatility, and trading volume for 25 NYSE stocks. We show that volume and volatility are long memory but not fractionally cointegrated in most cases. We also find right tail dependence in the volatility and volume innovations...

  17. Market volatility modeling for short time window

    Science.gov (United States)

    de Mattos Neto, Paulo S. G.; Silva, David A.; Ferreira, Tiago A. E.; Cavalcanti, George D. C.

    2011-10-01

    The gain or loss of an investment can be defined by the movement of the market. This movement can be estimated by the difference between the magnitudes of two stock prices in distinct periods and this difference can be used to calculate the volatility of the markets. The volatility characterizes the sensitivity of a market change in the world economy. Traditionally, the probability density function (pdf) of the movement of the markets is analyzed by using power laws. The contributions of this work is two-fold: (i) an analysis of the volatility dynamic of the world market indexes is performed by using a two-year window time data. In this case, the experiments show that the pdf of the volatility is better fitted by exponential function than power laws, in all range of pdf; (ii) after that, we investigate a relationship between the volatility of the markets and the coefficient of the exponential function based on the Maxwell-Boltzmann ideal gas theory. The results show an inverse relationship between the volatility and the coefficient of the exponential function. This information can be used, for example, to predict the future behavior of the markets or to cluster the markets in order to analyze economic patterns.

  18. Volatile flavor compounds in yogurt: a review.

    Science.gov (United States)

    Cheng, Hefa

    2010-11-01

    Considerable knowledge has been accumulated on the volatile compounds contributing to the aroma and flavor of yogurt. This review outlines the production of the major flavor compounds in yogurt fermentation and the analysis techniques, both instrumental and sensory, for quantifying the volatile compounds in yogurt. The volatile compounds that have been identified in plain yogurt are summarized, with the few key aroma compounds described in detail. Most flavor compounds in yogurt are produced from lipolysis of milkfat and microbiological transformations of lactose and citrate. More than 100 volatiles, including carbonyl compounds, alcohols, acids, esters, hydrocarbons, aromatic compounds, sulfur-containing compounds, and heterocyclic compounds, are found in yogurt at low to trace concentrations. Besides lactic acid, acetaldehyde, diacetyl, acetoin, acetone, and 2-butanone contribute most to the typical aroma and flavor of yogurt. Extended storage of yogurt causes off-flavor development, which is mainly attributed to the production of undesired aldehydes and fatty acids during lipid oxidation. Further work on studying the volatile flavor compounds-matrix interactions, flavor release mechanisms, and the synergistic effect of flavor compounds, and on correlating the sensory properties of yogurt with the compositions of volatile flavor compounds are needed to fully elucidate yogurt aroma and flavor.

  19. Topical anesthesia with eutetic mixture of local anesthetics cream in vasectomy: 2 randomized trials

    DEFF Research Database (Denmark)

    Honnens de Lichtenberg, M; Krogh, J; Rye, B

    1992-01-01

    Two paired randomized trials testing topical anesthesia with a eutetic mixture of local anesthetics (EMLA cream*) in vasectomy were performed. In 1 trial EMLA cream was applied on 1 side of the scrotum, while infiltration anesthesia into the skin and subcutaneous tissue with mepivacaine was used...... on the contralateral side. All but 1 of the 13 patients (p less than 0.05) preferred infiltration anesthesia because of pain as the incision reached the subcutaneous tissue. In the other trial 29 patients received EMLA cream on 1 side of the scrotum before bilateral mepivacaine infiltration. There was significantly...... less pain on the sides with the anesthetic cream (p less than 0.001). Many patients would pay the price of the cream. In conclusion, EMLA cream cannot replace but it can supplement infiltration anesthesia during vasectomy....

  20. The cochlear implantation surgery: A review of anesthetic considerations and implications

    Directory of Open Access Journals (Sweden)

    Sukhminder Jit Singh Bajwa

    2013-01-01

    Full Text Available The advancement in the technology of the cochlear implants has resulted in increasing trend of cochlear implantation in both the children and elderly population. The anesthesiologist is faced with the task of smoothly conducting the surgery without any interference in the stimulation techniques used. The preoperative evaluation is mainly focused on the presence of any congenital anomalies in these patients which may affect anesthetic technique. The reduction of anxiety of the patient as well as the parents of small children is an important aspect of the preoperative visit. Intraoperatively the anesthetic technique chosen should not interfere with the stimulation of the cochlear implant electrode assembly. The postoperative management is mainly focused at prevention of agitation and good analgesia. A close cooperation between the surgeon and the anesthesiologist is essential for a positive outcome in this surgery. The current review focuses on the important anesthesia aspects related to cochlear implant surgery.

  1. Heightened motor and sensory (mirror-touch) referral induced by nerve block or topical anesthetic.

    Science.gov (United States)

    Case, Laura K; Gosavi, Radhika; Ramachandran, Vilayanur S

    2013-08-01

    Mirror neurons allow us to covertly simulate the sensation and movement of others. If mirror neurons are sensory and motor neurons, why do we not actually feel this simulation- like "mirror-touch synesthetes"? Might afferent sensation normally inhibit mirror representations from reaching consciousness? We and others have reported heightened sensory referral to phantom limbs and temporarily anesthetized arms. These patients, however, had experienced illness or injury of the deafferented limb. In the current study we observe heightened sensory and motor referral to the face after unilateral nerve block for routine dental procedures. We also obtain double-blind, quantitative evidence of heightened sensory referral in healthy participants completing a mirror-touch confusion task after topical anesthetic cream is applied. We suggest that sensory and motor feedback exist in dynamic equilibrium with mirror representations; as feedback is reduced, the brain draws more upon visual information to determine- perhaps in a Bayesian manner- what to feel.

  2. Rapid automated classification of anesthetic depth levels using GPU based parallelization of neural networks.

    Science.gov (United States)

    Peker, Musa; Şen, Baha; Gürüler, Hüseyin

    2015-02-01

    The effect of anesthesia on the patient is referred to as depth of anesthesia. Rapid classification of appropriate depth level of anesthesia is a matter of great importance in surgical operations. Similarly, accelerating classification algorithms is important for the rapid solution of problems in the field of biomedical signal processing. However numerous, time-consuming mathematical operations are required when training and testing stages of the classification algorithms, especially in neural networks. In this study, to accelerate the process, parallel programming and computing platform (Nvidia CUDA) facilitates dramatic increases in computing performance by harnessing the power of the graphics processing unit (GPU) was utilized. The system was employed to detect anesthetic depth level on related electroencephalogram (EEG) data set. This dataset is rather complex and large. Moreover, the achieving more anesthetic levels with rapid response is critical in anesthesia. The proposed parallelization method yielded high accurate classification results in a faster time.

  3. Anesthetic management of a child with relapsing polychondritis:a case report

    Institute of Scientific and Technical Information of China (English)

    JI Cun-liang; ZHANG Bing-xi; HU Gui-zhi

    2009-01-01

    @@ Relapsing polychondritis (RP) is a rare disorder of unknown cause.It is characterized by recurrent inflammation of cartilage and connective tissue.Airway complications are the most serious manifestations.1,2 The anesthetic management of patients with RP is challenging.Airway management is of primary importance because of the potential for collapse of supporting airway structures with resulting inability to intubate and ventilate the patient) Although it tends to occur in middle age (>40 years),it has been reported in younger individuals.Herein we report a case of anesthetic management of a child with RP for tracheotomy combined with insertion of T tube stent and review several other cases.

  4. Effectiveness of topical anesthetics on reducing tactile sensitivity in the paws of newborn rats.

    Science.gov (United States)

    Strain, Misty M; Vineyard, Mary Ann; Roberto, Megan E; Brumley, Michele R

    2014-01-01

    The aim of this study was to evaluate the effectiveness of three local, topical anesthetics on touch response thresholds of the paws of 1-day-old rats. Touch response thresholds were measured using Semmes Weinstein monofilaments after treatment of the paws with EMLA (2.5% lidocaine and 2.5% prilocaine), alcaine (.5% proparacaine), triocaine (20% benzocaine, 6% lidocaine, and 4% tetracaine), or petroleum jelly (treatment control). Touch thresholds significantly increased after treatment with EMLA 18% of the time, and there was no evidence of a systemic effect. Touch thresholds were not significantly altered after treatment with alcaine, triocaine, or petroleum jelly. Therefore, EMLA appears to be a slightly effective topical anesthetic for reducing tactile sensitivity in newborn rats.

  5. Benzocaine as a fish anesthetic: efficacy and safety for spawning-phase salmon

    Science.gov (United States)

    Gilderhus, P.A.

    1990-01-01

    The anesthetic benzocaine was tested for efficacy and safety for spawning-phase chinook salmon (Oncorhynchus tshawytscha) and Atlantic salmon (Salmo salar) at federal fish hatcheries. Tests were conducted in the existing hatchery water supplies (soft water; temperatures, 10–13 °C. Crystalline benzocaine was dissolved in ethanol (1 g/30 mL), and aliquots of that stock solution were added to the water in test tanks. Benzocaine concentrations of 25–30 mg/L anesthetized most fish in less than 3.5 min, and most fish recovered in less than 10 min after 15 min of exposure. Safety margins were narrow; both species tolerated 30 mg/L for about 20 min, but 25 min of exposure caused deaths. For 15 min exposures, concentrations of 35 mg/L for chinook salmon and 40 mg/L for Atlantic salmon were lethal.

  6. Anesthetic Approach to a Patient with Epidermolysis Bullosa: A Case Report

    Directory of Open Access Journals (Sweden)

    Ersin KOKSAL

    2015-09-01

    Full Text Available Epidermolysis Bullosa (EB is characterized by fragility and formation of blisters in the skin and mucosal membranes. Due to blisters on the airway and occurring new blisters as a result of anesthetic or surgical procedures may complicate anesthesia management. In this case report, we present the anesthetic approach of a 6 years old case with EB who underwent reconstructive surgery. After premedication and optimal monitorization, intravenous (IV anesthesia and analgesia was administered. Associated with the oropharyngeal lesions and limitation to reach an adequate mouth opening, we preferred the facemask to maintain ventilation. Neither new lesions nor complications were detected during or after surgery. [J Contemp Med 2015; 5(3.000: 192-195

  7. [The individual and integral effects of brief simulated descents and anesthetic pharmacological preparations on human metabolism].

    Science.gov (United States)

    Deviatova, N V; Buravkova, L B

    1999-01-01

    In short-term chamber (GVK-250) "descents" by three healthy male volunteers mechanisms of hyperbaric narcosis against high partial pressures of indifferent nitrogen and argon were compared with anesthetic ketamine and sibason. Clinical biochemistry was engaged to determine any possible changes in metabolism due to the "descents" up to 0.4-0.6 MPa. Cubital vein blood was sampled prior to and following decompression. Plasma spectrophotometry was performed using biochemical analyzer EPAC-6140 (Eppendorf, Germany) and standard sets of reagents by Raichem (USA) and Biocon (Germany). On the whole, shifts in albumin, total protein, uric acid, lactate, and the creatine kinase activity were found to be within the physiological norm. However, several cases of excursion outside the boundaries of the clinical norm (A/T, AT, lactate dehydrogenase, triglycerides, lipase) could be associated with changes in the functional state of the liver caused by administration of the anesthetics during the hyperbaric exposure.

  8. [Body temperature, Aldrete-Kroulik index, and patient discharge from the post-anesthetic recovery unit].

    Science.gov (United States)

    de Castro, Fernanda Salim Ferreira; Peniche, Aparecida de Cássia Giani; Mendoza, Isabel Yovana Quispe; Couto, Andréa Tamancoldi

    2012-08-01

    Patient discharge from post-anesthetic recovery (PAR) depends, among other factors, on normothermia and the patient's score on the Aldrete-Kroulik index. The objective of this study was to verify the relationship between the Aldrete-Kroulik index and body temperature in patients. This study was performed at the University of São Paulo University Hospital. Convenience sampling was used, and the sample consisted of 60 patients of ages between 18 and 60 years who underwent general anesthesia. The patients' body temperature was obtained by tympanic measurement, and the Aldrete-Kroulik index was measured on admission and at discharge from post-anesthetic recovery. The data were processed using SPSS, considering a significance level of 5%, and the Spearman and Wilcoxon tests were applied. In conclusion, no significant correlation was found between the two parameters for discharge.

  9. Anesthetic considerations of an emergency decompressive craniotomy complicated with Ebstein's anomaly and atrial septal defect

    Institute of Scientific and Technical Information of China (English)

    XIN Xin; TANG Shuai; WANG Ling; ZHAO Jing; LI Gui-lin; GUO Li-lin; HUANG Yu-guang

    2011-01-01

    Despite considerable published papers regarding Ebstein's anomaly (EA) patients receiving open-heart tricuspid valve replacement, non-cardiac emergency surgeries were rarely reported. We report a case of emergency decormpressive craniotormy in a patient with EA. Anesthesiologists should pay special attention to the complications and anesthetic management during the non-cardiac surgeries performed in EA patients.hile papers regarding Ebstein's anomaly (EA)patients receiving open-heart tricuspid valve replacement are numerous, the reports of non-cardiac emergency surgeries have not been to the same degree.We report a case of emergency decompressive craniotomy in a patient with EA. This case report describes the symptoms and anesthetic management during the surgery.

  10. A Novel and Innovative Way of Nasogastric Tube Insertion in Anesthetized Intubated Patient

    Science.gov (United States)

    Sahu, Sandeep; Kishore, Kamal; Sachan, Vertika; Chatterjee, Arnidam

    2017-01-01

    Nasogastric tube (NGT) placement in anesthetized and intubated is sometimes very challenging with more than 50% failure rate in the first attempt. We describe a newer innovative Sahu's three in one, technique with use of GlideScope and forward placement of intubated trachea by external laryngeal maneuver, these both techniques lead to separation of trachea from esophagus so that endoscopic jejunal feeding tube guide wire strengthen NGT can be guided and manipulated to esophagus under direct vision. After informed consent, we used Sahu's three in one combo technique to insert NGT in adult anesthetized and intubated patients of both the sexes with high success in the first attempt. We found this technique easy, helpful, less time consuming with high success rate.

  11. [Anesthetic management of a Dialysis Patient with Chronic Inflammatory Demyelinating Polyneuropathy].

    Science.gov (United States)

    Takahashi, Yoshihiro; Hara, Koji; Sata, Takeyoshi

    2015-11-01

    We report the successful management of anesthesia in a 46-year-old male dialysis patient with chronic inflammatory demyelinating polyneuropathy (CIDP). He underwent an osteosynthesis of the ankle joint using general anesthesia combined with epidural anesthesia. The anesthetic concerns in patients with CIDP are the possibility of postoperative respiratory dysfunction due to anesthetics or muscle relaxants and that of postoperative neurological deterioration due to spinal or epidural anesthesia. In this case, sevoflurane (1.5-2%) did not cause respiratory dysfunction postoperatively and muscle relaxant effect of rocuronium was effectively reversed by sugammadex. Epidural anesthesia using ropivacaine (0.2-0.375%) and fentanyl did not worsen the neurological symptoms of CIDP post-operatively.

  12. The effects of anesthetics and misonidazole on the development of radiation-induced lung damage in mice

    Energy Technology Data Exchange (ETDEWEB)

    Down, J.D. (Inst. of Cancer Research, Surrey, England); Collis, C.H.; Jeffery, P.K.; Steel, G.G.

    1983-02-01

    The measurement of breathing frequency as a functional end-point of radiation-induced lung injury in mice allowed two phases of damage to be discerned; the first was manifest at 12-20 weeks after irradiation, the second beyond 28 weeks. Anesthesia by pentobarbitone sodium or steroids gave significant radioprotection of the lung during the early pneumonitic phase. Addition of the hypoxic cell sensitizer misonidazole removed the protective influence of the anesthetics but did not sensitize the lungs of unanesthetized mice. No anesthetic protection was detected for the late response, showing evidence for dissociation between early and late lung damage. The degree of epilation was measured on the dorsal thoracic region of the same mice. Protection by anesthetics and its reversal by misonidazole was also demonstrated. These results provide a warning of potential hazards in the laboratory evaluation of chemical radiosensitizers. The use of anesthetics at the time of irradiation could lead to an exaggerated enhancement of normal tissue damage.

  13. Radiofrequency ablation of hepatocellular carcinomas: A new spectrum of anesthetic experience at a tertiary care hospital in Pakistan

    Directory of Open Access Journals (Sweden)

    Faisal Shamim

    2017-01-01

    Conclusions: Percutaneous RFA is a safe treatment of hepatocellular cancer. The procedure required good anesthetic support in the form of sedation-analgesia or complete GA that ensures maximum patient comfort and technical success of the procedure.

  14. Standardization of 2-phenoxyethanol as anesthetic for juvenile Brycon cephalus (Gunther, 1869: the use in field procedures

    Directory of Open Access Journals (Sweden)

    Inoue Luis Antônio Kioshi Aoki

    2004-01-01

    Full Text Available Hyper motility is a negative factor in fish handling procedures due to the risks of damages to the animals. Chemicals are widely used to anesthetize fish during biometry and many other handling procedures. 2-Phenoxyethanol is largely employed, but many studies are necessary about tropical fish responses. The present research evaluated the anesthesia induction time for juvenile matrinxã submitted to eight different levels of 2-phenoxyethanol. The range of 2-phenoxyethanol concentration was 250-600mg liter-1. Induction time of anesthesia decreased as a function of 2-phenoxyethanol concentrations. Fish were safely anesthetized approximately after one minute of exposure to 2-phenoxyethanol batches in concentrations above 400mg/liter, and the recover period was about one minute for all anesthetic concentrations. 2-Phenoxyethanol is a safe anesthetic for juvenile matrinxã even in exposures up to 600mg liter-1 being recommended for many field procedures of fish handling.

  15. Anesthetic drug wastage in the operation room: A cause for concern

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    Kapil Chaudhary

    2012-01-01

    Full Text Available Context: The cost of anesthetic technique has three main components, i.e., disposable supplies, equipments, and anesthetic drugs. Drug budgets are an easily identifiable area for short-term savings. Aim: To assess and estimate the amount of anesthetic drug wastage in the general surgical operation room. Also, to analyze the financial implications to the hospital due to drug wastage and suggest appropriate steps to prevent or minimize this wastage. Settings and Design: A prospective observational study conducted in the general surgical operation room of a tertiary care hospital. Materials and Methods: Drug wastage was considered as the amount of drug left unutilized in the syringes/vials after completion of a case and any ampoule or vial broken while loading. An estimation of the cost of wasted drug was made. Results: Maximal wastage was associated with adrenaline and lignocaine (100% and 93.63%, respectively. The drugs which accounted for maximum wastage due to not being used after loading into a syringe were adrenaline (95.24%, succinylcholine (92.63%, lignocaine (92.51%, mephentermine (83.80%, and atropine (81.82%. The cost of wasted drugs for the study duration was 46.57% (Rs. 16,044.01 of the total cost of drugs issued/loaded (Rs. 34,449.44. Of this, the cost of wastage of propofol was maximum being 56.27% (Rs. 9028.16 of the total wastage cost, followed by rocuronium 17.80% (Rs. 2856, vecuronium 5.23% (Rs. 840, and neostigmine 4.12% (Rs. 661.50. Conclusions: Drug wastage and the ensuing financial loss can be significant during the anesthetic management of surgical cases. Propofol, rocuronium, vecuronium, and neostigmine are the drugs which contribute maximally to the total wastage cost. Judicious use of these and other drugs and appropriate prudent measures as suggested can effectively decrease this cost.

  16. Development of transmucosal patch loaded with anesthetic and analgesic for dental procedures and in vivo evaluation

    OpenAIRE

    Nidhi M; Patro MN; Kusumvalli S; Kusumdevi V

    2016-01-01

    Malviya Nidhi,1 M Nagaraju Patro,1 Somisetty Kusumvalli,2 Vemula Kusumdevi1 1Department of Pharmaceutics, Al-Ameen College of Pharmacy, 2Department of Endodontics and Conservative Dentistry, Sri Rajiv Gandhi College of Dental Sciences, Bengaluru, Karnataka, India Abstract: Most of the dental surgeries require preoperative anesthetic and postoperative analgesic for painless procedures. A multidrug transmucosal drug delivery system loaded with lignocaine (Lig) base for immediate release and s...

  17. Chiral selective effects of doxazosin enantiomers on blood pressure and urinary bladder pressure in anesthetized rats

    Institute of Scientific and Technical Information of China (English)

    Shi-ping MA; Lei-ming REN; Ding ZHAO; Zhong-ning ZHU; Miao WANG; Hai-gang LU; Li-hua DUAN

    2006-01-01

    Aim: To study chiral selective effects of doxazosin enantiomers on blood pressure and urinary bladder pressure in anesthetized rats. Methods: In anesthetized rats, the carotid blood pressure, left ventricular pressure of the heart and the urinary bladder pressure were recorded. Results: Administration of S-doxazosin at 0.25, 2.5, 25, and 250 nmol/kg iv produced a dose-dependent decrease in blood pressure, but its depressor effect was significantly weaker than that induced by R-doxazosin and racemic-doxazosin (rac-doxazosin), and the ED30 values (producing a 30% decrease in mean arterial pressure) of R-doxazosin, rac-doxazosin and S-doxazosin were 15.64,45.93, and 128.81, respectively. Rac-doxazosin and its enantiomers administered cumulatively in anesthetized rats induced a dose-dependent decrease in the left ventricular systolic pressure and ±dp/dtmax, and the potency order of the 3 agents was R-doxazosin >rac-doxazosin >S-doxazosin. Rac-doxazosin and its enantiomers decreased the vesical micturition pressure dose-dependently at 2.5,25, and 250 nmol/kg, and the inhibitory potency among the 3 agents was not significantly different. Conclusion: S-doxazosin decreases the carotid blood pressure and left ventricular pressure of the heart less than R-doxazosin and rac-doxazosin, but its effect on the vesical micturition pressure is similar to R-doxazosin and rac-doxazosin, indicating that S-doxazosin has chiral selectivity between cardiovascular system and urinary system in anesthetized rats.

  18. Evaluation and Management of Hypersensitivity to Local Anesthetics in Pediatric Dentistry

    OpenAIRE

    1987-01-01

    The clinical histories of four children with a history of adverse reactions to local anesthesia and who required dental treatment are reviewed retrospectively. The children described had been referred to the allergy unit for evaluation between 1984 and 1985 and are representative of the dilemma of cases of suspected hypersensitivity to local anesthetics. The first two cases had been previously treated without the use of regional anesthesia because of a family history of atopic reactions as we...

  19. Assessment of occupational exposure of medical personnel to inhalatory anesthetics in Poland

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    Małgorzata Kucharska

    2014-02-01

    Full Text Available Objectives: Despite common use of inhalatory anesthetics, such as nitrous oxide (N2O, halothane, sevoflurane, and the like, occupational exposure to these substances in operating theatres was not monitored in Poland until 2006. The situation changed when maximum admissible concentration (MAC values for anesthetics used in Poland were established in 2005 for N2O, and in 2007 for sevoflurane, desflurane and isoflurane. The aim of this work was to assess occupational exposure in operating rooms on the basis of reliable and uniform analytical procedures. Material and Methods: The method for the determination of all anesthetics used in Poland, i.e. nitrous oxide, sevoflurane, isoflurane, desflurane, and halothane, was developed and validated. The measurements were performed in 2006-2010 in 31 hospitals countrywide. The study covered 117 operating rooms; air samples were collected from the breathing zone of 146 anesthesiologists, and 154 nurses, mostly anaesthetic. The measurements were carried out during various surgical operations, mostly on adult patients but also in hospitals for children. Results: Time weighted average concentrations of the anesthetics varied considerably, and the greatest differences were noted for N2O (0.1-1438.5 mg/m3; 40% of the results exceeded the MAC value. Only 3% of halothane, and 2% of sevoflurane concentrations exceeded the respective MAC values. Conclusions: Working in operating theatres is dangerous to the health of the operating staff. The coefficient of combined exposure to anesthesiologists under study exceeded the admissible value in 130 cases, which makes over 40% of the whole study population. Most of the excessive exposure values were noted for nitrous oxide. Med Pr 2014;65(1:43–54

  20. Methemoglobin levels in generally anesthetized pediatric dental patients receiving prilocaine versus lidocaine.

    Science.gov (United States)

    Gutenberg, Lauren L; Chen, Jung-Wei; Trapp, Larry

    2013-01-01

    The purpose of this study was to measure and compare peak methemoglobin levels and times to peak methemoglobin levels following the use of prilocaine and lidocaine in precooperative children undergoing comprehensive dental rehabilitation under general anesthesia. Ninety children, 3-6 years of age, undergoing dental rehabilitation under general anesthesia were enrolled and randomly assigned into 3 equal groups: group 1, 4% prilocaine plain, 5 mg/kg; group 2, 2% lidocaine with 1:100,000 epinephrine, 2.5 mg/kg; and group 3, no local anesthetic. Subjects in groups 1 and 2 were administered local anesthetic prior to restorative dental treatment. Methemoglobin levels (SpMET) were measured and recorded throughout the procedure using a Masimo Radical-7 Pulse Co-Oximeter (Masimo Corporation, Irvine, Calif, RDS-1 with SET software with methemoglobin interface). Data were analyzed using chi-square, one-way analysis of variance (ANOVA), and Pearson correlation (significance of P < .05). Group 1 had a significantly higher mean peak SpMET level at 3.55% than groups 2 and 3 at 1.63 and 1.60%, respectively. The mean time to peak SpMET was significantly shorter for group 3 at 29.50 minutes than that of group 1 at 62.73 and group 2 at 57.50 minutes. Prilocaine, at 5 mg/kg in pediatric dental patients, resulted in significantly higher peak SpMET levels than lidocaine and no local anesthetic. In comparison to no local anesthetic, the administration of prilocaine and lidocaine caused peak SpMET levels to occur significantly later in the procedure.

  1. Brainstem Stimulation Increases Functional Connectivity of Basal Forebrain-Paralimbic Network in Isoflurane-Anesthetized Rats

    OpenAIRE

    Pillay, Siveshigan; Liu, Xiping; Baracskay, Péter; Hudetz, Anthony G.

    2014-01-01

    Brain states and cognitive-behavioral functions are precisely controlled by subcortical neuromodulatory networks. Manipulating key components of the ascending arousal system (AAS), via deep-brain stimulation, may help facilitate global arousal in anesthetized animals. Here we test the hypothesis that electrical stimulation of the oral part of the pontine reticular nucleus (PnO) under light isoflurane anesthesia, associated with loss of consciousness, leads to cortical desynchronization and sp...

  2. Improvement of Lidocaine Local Anesthetic Action Using Lallemantia royleana Seed Mucilage as an Excipient

    OpenAIRE

    Atabaki, Rabi; Hassanpour-Ezatti, Majid

    2014-01-01

    Lallemantia royleana (Balangu) is a well known Iranian medicinal plant that its seed mucilage has many applications in modern pharmacology. Plant mucilage traditionally was used as a gel supplement, and natural matrix for sustained release of drugs. But it seems that these compounds are not a simple additive and also have many undiscovered pharmacological properties. In this research, the anesthetic action of gel prepared from Balangu mucilage alone and its mixture with lidocaine hydrochlorid...

  3. Analysis on the factors associated with treatment failure of using anesthetics in refractory status epilepticus

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    Ying-ying SU

    2015-11-01

    Full Text Available Objective To analyze the related factors associated with immediate treatment failure of using anesthetics in refractory status epilepticus (RSE.  Methods Thirty patients derived from Neurocritical Care Unit of Xuanwu Hospital from January 2004 to December 2013 were divided into 2 groups (acute treatment failure group and acute treatment success group based on the treatment outcome 6 h after intravenous injection of anesthetics. Univariate and multivariate forward Logistic regression analyses were used to analyze and screen the risk factors associated with immediate treatment failure, and calculate the failure rate of final outcome.  Results According to the results of univariate and multivariate Logistic regression analyses, among influencing factors such as sex, age, etiology, Acute Physiology and Chronic Health EvaluationⅡ (APACHEⅡ, type of status epilepticus (SE, type of antiepileptic drugs (AEDs, total duration of primary treatment, duration of prehospital primary treatment, duration of posthospital primary treatment, type of RSE and primary choice of anesthetics, only total duration of primary treatment was the independent risk factor for immediate treatment failure (OR = 1.007, 95%CI: 1.000-1.014; P = 0.047. The rate of immediate treatment failure of RSE by using anesthetics was 50% (15/30, and the rate of final treatment failure was 43.33% (13/30. The ratio of final treatment failure was much higher in acute treatment failure group than that in acute treatment success group (10/15 vs 3/15, P = 0.025.  Conclusions The acute treatment result of RSE depends on the total duration of primary treatment, and determinates the final result of treatment. On the basis of treating primary disease, the therapy to terminate SE or RSE should be started as early as possible. DOI: 10.3969/j.issn.1672-6731.2015.11.008

  4. Induction of burst suppression or coma using intravenous anesthetics in refractory status epilepticus.

    Science.gov (United States)

    Kang, Bong Su; Jung, Keun-Hwa; Shin, Jeong-Won; Moon, Jang Sup; Byun, Jung-Ick; Lim, Jung-Ah; Moon, Hye Jin; Kim, Young-Soo; Lee, Soon-Tae; Chu, Kon; Lee, Sang Kun

    2015-05-01

    General anesthetic-induced coma therapy has been recommended for the treatment of refractory status epilepticus (RSE). However, the influence of electroencephalographic (EEG) burst suppression (BS) on outcomes still remains unclear. This study investigated the impact of intravenous anesthetic-induced BS on the prognosis of RSE using a retrospective analysis of all consecutive adult patients who received intravenous anesthetic treatment for RSE at the Seoul National University Hospital between January 2006 and June 2011. Twenty-two of the 111 episodes of RSE were enrolled in this study. Of the 22 RSE patients, 12 (54.5%) were women and 18 (81.4%) exhibited generalized convulsive status epilepticus. Sixteen patients (72.7%) were classified as having acute symptomatic etiology, including three patients with anoxic encephalopathy, and others with remote symptomatic etiology. Only two patients (9.1%) had a favorable Status Epilepticus Severity Score (0-2) at admission. All patients received midazolam (MDZ) as a primary intravenous anesthetic drug for RSE treatment; three (13.6%) received MDZ and propofol, and one (4.5%) received MDZ and pentobarbital. The rates of mortality and poor outcome at discharge were 13.6% (n=3) and 54.5% (n=12), respectively. While BS was achieved in six (27.5%) patients, it was not associated with mortality or poor outcome. Induced BS was associated with prolonged hospital stay in subgroup analysis when excluding anoxic encephalopathy. Our results suggest that induction of BS for treating RSE did not affect mortality or outcome at discharge and may lead to an increased length of hospital stay.

  5. Multifractal diffusion entropy analysis on stock volatility in financial markets

    Science.gov (United States)

    Huang, Jingjing; Shang, Pengjian; Zhao, Xiaojun

    2012-11-01

    This paper introduces a generalized diffusion entropy analysis method to analyze long-range correlation then applies this method to stock volatility series. The method uses the techniques of the diffusion process and Rényi entropy to focus on the scaling behaviors of regular volatility and extreme volatility respectively in developed and emerging markets. It successfully distinguishes their differences where regular volatility exhibits long-range persistence while extreme volatility reveals anti-persistence.

  6. Do Local Anesthetics Containing Epinephrine Affect Blood Pressure in the Elderly?

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    Ayse Arpaci

    2014-11-01

    Full Text Available Aim: Dental procedures are often performed under local anesthesia. Vasoconstrictors added to local anesthetics might have unwanted effects in the elderly and in patients with comorbid diseases. The aim of this study was to evaluate the effects of local anesthetics containing epinephrine on blood pressure in elderly patients undergoing dental procedures. Material and Method: The study included 479 patients (age, 67.37±6.62 who underwent tooth extraction. Patient demographics, current health conditions, and blood pressure values were recorded before local anesthesia and at 5 minutes after anesthesia administration. Patients were divided into 4 groups: Group I (n=272 received 40 mg articaine/0.012 mg epinephrine (Ultracain® D-S Forte; Group II (n=196 received 40 mg articaine/0.01 mg epinephrine (Maxicaine FORT; Group III (n=6 received 40 mg articaine/0.006 mg epinephrine (Ultracain® D-S; and Group IV (n=5 received 40 mg articaine/0.005 mg epinephrine (Maxicaine. Statistical analyses were performed using SPSS version 20.0. Results: A total of 479 patients were included in the analysis. Hypertension and diabetes were the most frequently reported comorbidities among these patients. Blood pressure values after administration of anesthesia were higher than those recorded before the procedure in all groups. Discussion: Local anesthetics containing epinephrine are not associated with a significant increase in blood pressure in elderly patients undergoing dental procedures. Obtaining a detailed clinical history may reduce the risk of procedure-related morbidity.

  7. Qualitative evaluation of coronary flow during anesthetic induction using thallium-201 perfusion scans

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    Kleinman, B.; Henkin, R.E.; Glisson, S.N.; el-Etr, A.A.; Bakhos, M.; Sullivan, H.J.; Montoya, A.; Pifarre, R.

    1986-02-01

    Qualitative distribution of coronary flow using thallium-201 perfusion scans immediately postintubation was studied in 22 patients scheduled for elective coronary artery bypass surgery. Ten patients received a thiopental (4 mg/kg) and halothane induction. Twelve patients received a fentanyl (100 micrograms/kg) induction. Baseline thallium-201 perfusion scans were performed 24 h prior to surgery. These scans were compared with the scans performed postintubation. A thallium-positive scan was accepted as evidence of relative hypoperfusion. Baseline hemodynamic and ECG data were obtained prior to induction of anesthesia. These data were compared with the data obtained postintubation. Ten patients developed postintubation thallium-perfusion scan defects (thallium-positive scan), even though there was no statistical difference between their baseline hemodynamics and hemodynamics at the time of intubation. There was no difference in the incidence of thallium-positive scans between those patients anesthetized by fentanyl and those patients anesthetized with thiopental-halothane. The authors conclude that relative hypoperfusion, and possibly ischemia, occurred in 45% of patients studied, despite stable hemodynamics, and that the incidence of these events was the same with two different anesthetic techniques.

  8. Evaluation of common anesthetic and analgesic techniques for tail biopsy in mice.

    Science.gov (United States)

    Jones, Carissa P; Carver, Scott; Kendall, Lon V

    2012-11-01

    Tail biopsy in mice is a common procedure in genetically modified mouse colonies. We evaluated the anesthetic and analgesic effects of various agents commonly used to mitigate pain after tail biopsy. We used a hot-water immersion assay to evaluate the analgesic effects of isoflurane, ice-cold ethanol, ethyl chloride, buprenorphine, and 2-point local nerve blocks before studying their effects on mice receiving tail biopsies. Mice treated with ethyl chloride spray, isoflurane and buprenorphine, and 2-point local nerve blocks demonstrated increased tail-flick latency compared with that of untreated mice. When we evaluated the behavior of adult and preweanling mice after tail biopsy, untreated mice demonstrated behavioral changes immediately after tail biopsy that lasted 30 to 60 min before returning to normal. The use of isoflurane, isoflurane and buprenorphine, buprenorphine, 2-point nerve block, or ethyl chloride spray in adult mice did not significantly improve their behavioral response to tail biopsy. Similarly, the use of buprenorphine and ethyl chloride spray in preweanling mice did not improve their behavioral response to tail biopsy compared with that of the untreated group. However, immersion in bupivacaine for 30 s after tail biopsy decreased tail grooming behavior during the first 30 min after tail biopsy. The anesthetic and analgesic regimens tested provide little benefit in adult and preweanling mice. Given that tail biopsy results in pain that lasts 30 to 60 min, investigators should carefully consider the appropriate anesthetic or analgesic regimen to incorporate into tail-biopsy procedures for mice.

  9. Cardioprotective effects of anesthetic preconditioning in rats with ischemia-reperfusion injury: propofol versus isoflurane

    Institute of Scientific and Technical Information of China (English)

    Xing TAO; Ling-qiao LU; Qing XU; Shu-ren LI; Mao-tsun LIN

    2009-01-01

    Objective: We compare the cardioprotective effects of anesthetic preconditioning by propofol and/or isoflurane in rats with ischemia-reperfusion injury. Methods: Male adult Wistar rats were subjected to 60 min of anterior descending coronary artery occlusion followed by 120 min of reperfusion. Before the long ischemia, anesthetics were administered twice for 10 min followed by 5 min washout. Isoflurane was inhaled at I MAC (0.016) in I group, whereas propofol was inhaled intravenously at 37.5 mg/(kg.h) in P group. A combination ofisoflurane and propofol was administered simultaneously in I+P group. Results: In control (without anesthetic preconditioning, C group), remarkable myocardial infarction and apoptosis accompanied by an increased level of cardiac troponin T were noted 120 rain after ischemia-reperfusion. As compared to those of control group, I and P groups had comparable cardioprotection. In addition, I+P group shares with I and P groups the comparable cardioprotective effects in terms of myocardial infarction and cardiac troponin T elevation. Conclusion: A combination of isoflurane and propofol produced no ad-ditional cardioprotection.

  10. Anesthetic ketamine counteracts repetitive mechanical stress-induced learning and memory impairment in developing mice.

    Science.gov (United States)

    Peng, Sheng; Zhang, Yan; Wang, Hua; Ren, Bingxu; Zhang, Jiannan

    2011-10-01

    The aim of this study is to investigate whether ketamine, a noncompetitive N-methyl-D: -aspartate receptor (NMDAR) antagonist, had an influence on learning and memory in developing mice. Fifty Kunming mice aged 21 days were randomly divided into 5 subgroups (n = 10 for each) to receive intraperitoneal injection of equal volume of saline (S group) or ketamine (25, 50 or 100 mg/kg of body weight/day) for 7 consecutive days, or to be left untreated (C group). A step-down passive avoidance test was performed to evaluate learning and memory in these mice on days 8 and 9. Additionally, the expression of brain-derived neurotrophic factor (BDNF) in the hippocampus was determined. Rats receiving saline or sub-anesthetic dose of ketamine (25 mg/kg) showed significantly decreased abilities of learning and memory and reduced expression of BDNF, compared to the normal controls (P learning and memory and expression of BDNF were found for anesthetic doses of ketamine (50 or 100 mg/kg)-treated rats and controls (P > 0.05). Repetitive mechanical stress impairs learning and memory performance in developing mice, which may be associated with decreased BDNF expression. The stress-induced learning and memory impairment can be prevented by anesthetic doses of ketamine.

  11. Improvement of Lidocaine Local Anesthetic Action Using Lallemantia royleana Seed Mucilage as an Excipient.

    Science.gov (United States)

    Atabaki, Rabi; Hassanpour-Ezatti, Majid

    2014-01-01

    Lallemantia royleana (Balangu) is a well known Iranian medicinal plant that its seed mucilage has many applications in modern pharmacology. Plant mucilage traditionally was used as a gel supplement, and natural matrix for sustained release of drugs. But it seems that these compounds are not a simple additive and also have many undiscovered pharmacological properties. In this research, the anesthetic action of gel prepared from Balangu mucilage alone and its mixture with lidocaine hydrochloride are compared with the effect of commercial 2% lidocaine gel by rat tail flick test. Mucilage of Balangu seed alone showed analgesic effect. Duration and potency of anesthesia induced by gel containing mucilage alone (0.01 g/mL) were identical to commercial 2% lidocaine gel. But, local anesthetic potency and duration of gel made from 2% lidocaine-mucilage gel mixture was significantly higher than commercial 2% lidocaine gel. The gel prepared from mucilage causes a good analgesia with unknown mechanism. Besides, mixture of Balangu mucilage prepared gel with lidocaine improves lidocaine anesthesia. The increase in potency of lidocaine action results from mucilage dermal penetration enhancing effects; and longer anesthetic duration of this mixture are related to the capability of mucilage based gel for sustained drug release.

  12. Preparation and characterization of poly(ε-caprolactone) nanospheres containing the local anesthetic lidocaine.

    Science.gov (United States)

    Ramos Campos, Estefânia Vangelie; Silva de Melo, Nathalie Ferreira; Guilherme, Viviane Aparecida; de Paula, Eneida; Rosa, André Henrique; de Araújo, Daniele Ribeiro; Fraceto, Leonardo Fernandes

    2013-01-01

    The objective of this work was to develop a modified release system for the local anesthetic lidocaine (LDC), using poly(ε-caprolactone) (PCL) nanospheres (NSs), to improve the pharmacological properties of the drug when administered by the infiltration route. In vitro experiments were used to characterize the system and investigate the release mechanism. The NSs presented a polydispersion index of 0.072, an average diameter of 449.6 nm, a zeta potential of -20.1 mV, and an association efficiency of 93.3%. The release profiles showed that the release of associated LDC was slower than that of the free drug. Atomic force microscopy analyses showed that the spherical structure of the particles was preserved as a function of time, as well as after the release experiments. Cytotoxicity and pharmacological tests confirmed that association with the NSs reduced the toxicity of LDC, and prolonged its anesthetic action. This new formulation could potentially be used in applications requiring gradual anesthetic release, especially dental procedures.

  13. Effects of anesthetic agents on brain blood oxygenation level revealed with ultra-high field MRI.

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    Luisa Ciobanu

    Full Text Available During general anesthesia it is crucial to control systemic hemodynamics and oxygenation levels. However, anesthetic agents can affect cerebral hemodynamics and metabolism in a drug-dependent manner, while systemic hemodynamics is stable. Brain-wide monitoring of this effect remains highly challenging. Because T(2*-weighted imaging at ultra-high magnetic field strengths benefits from a dramatic increase in contrast to noise ratio, we hypothesized that it could monitor anesthesia effects on brain blood oxygenation. We scanned rat brains at 7T and 17.2T under general anesthesia using different anesthetics (isoflurane, ketamine-xylazine, medetomidine. We showed that the brain/vessels contrast in T(2*-weighted images at 17.2T varied directly according to the applied pharmacological anesthetic agent, a phenomenon that was visible, but to a much smaller extent at 7T. This variation is in agreement with the mechanism of action of these agents. These data demonstrate that preclinical ultra-high field MRI can monitor the effects of a given drug on brain blood oxygenation level in the absence of systemic blood oxygenation changes and of any neural stimulation.

  14. Physiological and hematological responses of Nile tilapia (Oreochromis Niloticus to different anesthetics during simulated transport conditions

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    Rodrigo Diana Navarro

    2016-06-01

    Full Text Available Minimization of stress during the transportation of live fish is essential in maintaining the welfare and performance of the animals. In order to test the hypothesis that stress during transport of fingerlings of Nile tilapia (Oreochromis niloticus can be reduced with the aid of the anesthetics menthol, eugenol or benzocaine, we have assessed the effects of these agents at various concentrations on the physiological parameters and survival rates of fish subjected to conditions simulating those normally used in transportation. Fingerlings (N = 1200 were fasted for 24 hours and distributed in 20 L polyethylene bags (N = 50 per bag containing 5 L of water and an anesthetic at the appropriate concentration. Fingerlings treated with menthol at 75 mg L-1, or eugenol or benzocaine at 20 mg L-1, maintained levels of plasma cortisol and glucose that were lower than those of the stressed but untreated controls and within the physiological limits of the baseline values for this species. Under these conditions, the survival rate was 100%, suggesting that stress was substantially reduced despite dense consignment. Treatments involving higher doses of the studied agents induced significant anesthetic toxicity.

  15. Temporal changes in ventricular function assessed echocardiographically in conscious and anesthetized mice.

    Science.gov (United States)

    Rottman, Jeffrey N; Ni, Gemin; Khoo, Michelle; Wang, Zhizhang; Zhang, Wei; Anderson, Mark E; Madu, Ernest C

    2003-11-01

    The mouse is an important model system for cardiovascular biology, with echocardiography a critical tool for noninvasive measurement of cardiac morphology and function. The feasibility and short-term temporal consistency of repeated echocardiographic measurements in conscious mice has not been previously evaluated. We performed serial 2-dimensional guided M-mode transthoracic echocardiographic measurements at 5- to 10-minute intervals over 60 minutes in conscious mice and in mice treated with 1 of 3 anesthetic regimens: ketamine and acepromazine (n = 14); pentobarbital (n = 14); and ketamine and xylazine (n = 13). Unanesthetized mice received intraperitoneal saline (n = 6) or no injection (n = 7). In sequentially repeated measurements over 1 hour in conscious mice, none of the measured or derived echocardiographic parameters differed from baseline, whereas all 3 anesthetic regimens produced significant, prolonged, and temporally variable decreases in heart rate and fractional shortening. The relationship between heart rate and fractional shortening was not altered by anesthetic choice. Serial echocardiographic assessments of cardiac function, dimension, and mass can be performed with high reproducibility in conscious mice.

  16. Benzocaine and clove oil as anesthetics for pejerrey (Odontesthes bonariensis fingerlings

    Directory of Open Access Journals (Sweden)

    J. Morato-Fernandes

    2013-10-01

    Full Text Available Pejerrey (Odontesthes bonariensis is a native species from Rio Grande do Sul, Uruguay and Argentina where it is of great economic importance for artisanal fishing. One difficulty in laboratory research with pejerrey is related to its sensitivity, as it presents higher basal cortisol levels than other freshwater species. For this reason, the aim of this work was to evaluate the efficiency of benzocaine and clove oil as anesthetics for pejerrey fingerlings. Two experiments were done where fingerlings (57±7.8mm and 1.1±0.44g were exposed to benzocaine with concentrations between 40mgL-1 and 120mgL-1 and to clove oil with concentrations between 12mgL-1 and 75mgL-1. Survival, anesthesia induction time and recovery time for each pharmaceutics were evaluated. Both benzocaine and clove oil pharmaceutics showed efficiency as anesthetics for pejerrey fingerlings, with negative correlation between the dose of anesthetics and the anesthesia induction time. For benzocaine, the concentrations between 80mgL-1 and 100mgL-1 showed better results, as for clove oil the optimal concentrations were between 25mgL-1 and 50mgL-1. On the other hand, the anesthesia recovery time did not present significant variation on the different concentrations of the tested products. The tested products are highly metabolizable by pejerrey.

  17. Cleft lip and palate: recommendations for dental anesthetic procedure based on anatomic evidences.

    Science.gov (United States)

    Trindade-Suedam, Ivy Kiemle; Gaia, Bruno Felipe; Cheng, Cheong Kuo; Trindade, Paulo Alceu Kiemle; Bastos, José Carlos da Cunha; Mattos, Beatriz Silva Câmara

    2012-02-01

    Patients with cleft lip and palate usually present dental anomalies of number, shape, structure and position in the cleft area and the general dentist is frequently asked to restore or extract those teeth. Considering that several anatomic variations are expected in teeth adjacent to cleft areas and that knowledge of these variations by general dentists is required for optimal treatment, the objectives of this paper are: 1) to describe changes in the innervation pattern of anterior teeth and soft tissue caused by the presence of a cleft, 2) to describe a local anesthetic procedure in unilateral and bilateral clefts, and 3) to provide recommendations to improve anesthetic procedures in patients with cleft lip and palate. The cases of 2 patients are presented: one with complete unilateral cleft lip and palate, and the other with complete bilateral cleft lip and palate. The patients underwent local anesthesia in the cleft area in order to extract teeth with poor bone support. The modified anesthetic procedure, respecting the altered course of nerves in the cleft maxilla and soft tissue alterations at the cleft site, was accomplished successfully and the tooth extraction was performed with no pain to the patients. General dentists should be aware of the anatomic variations in nerve courses in the cleft area to offer high quality treatment to patients with cleft lip and palate.

  18. Usefulness of permutation entropy as an anesthetic depth indicator in children.

    Science.gov (United States)

    Kim, Pil-Jong; Kim, Hong-Gee; Noh, Gyu-Jeong; Koo, Yong-Seo; Shin, Teo Jeon

    2015-04-01

    Permutation entropy (PE) as a complexity measure has been introduced to monitor anesthetic depth for adult. However, PE has not yet been evaluated for its clinical applicability as an indicator of anesthetic depth in children. Therefore, in order to investigate the validity of PE, we compared PE with BIS using pharmacodynamic (PD) modeling in children. Electroencephalogram (EEG) was obtained from BIS monitor during sevoflurane deepening and lightening protocol. End-tidal sevoflurane concentration (Etsevo) and BIS were measured simultaneously. PE was calculated from the processed EEG with the scale ranging from 0 to 100. NONMEM software was used to investigate the PD relationship between Etsevo with BIS and PE. Adjusted PE (APE) values were decreased as anesthesia deepened. APE and BIS showed significant linear correlation (P Emax model which describes the relationship between Etsevo and APE/BIS (E o : 78, E max : 17.6, C e50 : 2.5 vol%; γ: 13.1, k eo : 0.47 min(-1) for APE; E o : 89.4; E max : 15.7; C e50 : 2.2 vol%; γ: 6.6, keo: 0.52 min(-1) for BIS). PE seems to be a useful indicator of anesthetic depth, which is comparable to BIS in children.

  19. Cleft lip and palate: recommendations for dental anesthetic procedure based on anatomic evidences

    Directory of Open Access Journals (Sweden)

    Ivy Kiemle Trindade-Suedam

    2012-02-01

    Full Text Available Patients with cleft lip and palate usually present dental anomalies of number, shape, structure and position in the cleft area and the general dentist is frequently asked to restore or extract those teeth. Considering that several anatomic variations are expected in teeth adjacent to cleft areas and that knowledge of these variations by general dentists is required for optimal treatment, the objectives of this paper are: 1 to describe changes in the innervation pattern of anterior teeth and soft tissue caused by the presence of a cleft, 2 to describe a local anesthetic procedure in unilateral and bilateral clefts, and 3 to provide recommendations to improve anesthetic procedures in patients with cleft lip and palate. The cases of 2 patients are presented: one with complete unilateral cleft lip and palate, and the other with complete bilateral cleft lip and palate. The patients underwent local anesthesia in the cleft area in order to extract teeth with poor bone support. The modified anesthetic procedure, respecting the altered course of nerves in the cleft maxilla and soft tissue alterations at the cleft site, was accomplished successfully and the tooth extraction was performed with no pain to the patients. General dentists should be aware of the anatomic variations in nerve courses in the cleft area to offer high quality treatment to patients with cleft lip and palate.

  20. Efficiency of eugenol as anesthetic for the early life stages of Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Ribeiro, Paula A P; Miranda-Filho, Kleber C; Melo, Daniela C de; Luz, Ronald K

    2015-03-01

    In aquaculture, activities with anesthetic compounds are usually used in order to ensure the welfare of farmed fish, allowing handling out of water with decreased trauma by stress. Presently, there is no information about anesthetic action of eugenol in early life stages of Nile tilapia (Oreochromis niloticus). The objective of this study was to evaluate different concentrations of eugenol for larvae and juveniles of Nile tilapia. Sixty animals were used for each group of weight, group I = 0.02 g; group II = 0.08 g; group III = 0.22 g; group IV = 2.62 g; and group V = 11.64 g. The eugenol concentrations tested were 50, 75, 100, 125, 150 and 175 mg L-1. No mortality was reported during the tests with eugenol. Tilapia larvae with 0.02 g and juveniles around 11.64 g can be anesthetized with eugenol concentrations between 150 and 175 mg L-1, since they determine the shortest sedation time (23 and 72 seconds, for the group of lowest and highest weights, respectively).

  1. General anesthetics inhibit erythropoietin induction under hypoxic conditions in the mouse brain.

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    Tomoharu Tanaka

    Full Text Available BACKGROUND: Erythropoietin (EPO, originally identified as a hematopoietic growth factor produced in the kidney and fetal liver, is also endogenously expressed in the central nervous system (CNS. EPO in the CNS, mainly produced in astrocytes, is induced under hypoxic conditions in a hypoxia-inducible factor (HIF-dependent manner and plays a dominant role in neuroprotection and neurogenesis. We investigated the effect of general anesthetics on EPO expression in the mouse brain and primary cultured astrocytes. METHODOLOGY/PRINCIPAL FINDINGS: BALB/c mice were exposed to 10% oxygen with isoflurane at various concentrations (0.10-1.0%. Expression of EPO mRNA in the brain was studied, and the effects of sevoflurane, halothane, nitrous oxide, pentobarbital, ketamine, and propofol were investigated. In addition, expression of HIF-2α protein was studied by immunoblotting. Hypoxia-induced EPO mRNA expression in the brain was significantly suppressed by isoflurane in a concentration-dependent manner. A similar effect was confirmed for all other general anesthetics. Hypoxia-inducible expression of HIF-2α protein was also significantly suppressed with isoflurane. In the experiments using primary cultured astrocytes, isoflurane, pentobarbital, and ketamine suppressed hypoxia-inducible expression of HIF-2α protein and EPO mRNA. CONCLUSIONS/SIGNIFICANCE: Taken together, our results indicate that general anesthetics suppress activation of HIF-2 and inhibit hypoxia-induced EPO upregulation in the mouse brain through a direct effect on astrocytes.

  2. Anesthetic induction and recovery of Hippocampus reidi exposed to the essential oil of Lippia alba

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    Mauro Alves da Cunha

    Full Text Available The aim of this study was to identify the times of anesthetic induction and recovery in slender seahorses (Hippocampus reidi that were exposed to the essential oil of Lippia alba (EO, as well as the efficacy of EO as a stress-reducing agent in the transport of this species. Slender seahorses were placed in 1-L aquaria containing different concentrations of EO (0, 10, 20, 50, 150, 300 and 450 µL L-1, and after induction, fish were transferred to aquaria that were free of anesthetic to evaluate their recovery time. In an additional experiment, slender seahorses were transported in plastic bags with 15 µL L-1 of EO for 4 or 24 h. The increased concentration of EO proportionally decreased the time required for the induction of anesthesia. EO treatment (15 µL L-1 inhibited the increase in blood glucose levels that was provoked by transportation for 4 or 24 h. Transportation for 24 h also decreased the number of lymphocytes and increased the neutrophil count, and these effects were avoided with the addition of EO to the water. These results demonstrate that EO was effective as an anesthetic at concentrations of 10-20 µL L-1 for slight sedation and transport and at 150 µL L-1 for deep anesthesia in the slender seahorse.

  3. Behavioral response and pain perception to computer controlled local anesthetic delivery system and cartridge syringe

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    T D Yogesh Kumar

    2015-01-01

    Full Text Available Aim: The present study evaluated and compared the pain perception, behavioral response, physiological parameters, and the role of topical anesthetic administration during local anesthetic administration with cartridge syringe and computer controlled local anesthetic delivery system (CCLAD. Design: A randomized controlled crossover study was carried out with 120 children aged 7-11 years. They were randomly divided into Group A: Receiving injection with CCLAD during first visit; Group B: Receiving injection with cartridge syringe during first visit. They were further subdivided into three subgroups based on the topical application used: (a 20% benzocaine; (b pressure with cotton applicator; (c no topical application. Pulse rate and blood pressure were recorded before and during injection procedure. Objective evaluation of disruptive behavior and subjective evaluation of pain were done using face legs activity cry consolability scale and modified facial image scale, respectively. The washout period between the two visits was 1-week. Results: Injections with CCLAD produced significantly lesser pain response, disruptive behavior (P < 0.001, and pulse rate (P < 0.05 when compared to cartridge syringe injections. Application of benzocaine produced lesser pain response and disruptive behavior when compared to the other two subgroups, although the result was not significant. Conclusion: Usage of techniques which enhance behavioral response in children like injections with CCLAD can be considered as a possible step toward achieving a pain-free pediatric dental practice.

  4. Effect of needle design on pain from dental local anesthetic injections.

    Science.gov (United States)

    McPherson, Joanna Saenz; Dixon, Sara A; Townsend, Richard; Vandewalle, Kraig S

    2015-01-01

    The purpose of this randomized, double-blind clinical study was to evaluate the effectiveness of a larger-bore compared with a standard-bore dental local anesthetic needle of the same gauge in reducing pain during inferior alveolar (IA) and long buccal (LB) nerve block injections. Twenty active duty military or Department of Defense beneficiaries undergoing dental treatment were anesthetized using a split-mouth design with 4 anesthetic dental injections. Both sides of the mouth received IA nerve block and LB nerve injections, one using the 27-gauge large-bore Septoject XL needle and other using a 27-gauge standard-bore Septoject needle. Patients rated the pain experienced with each method using a visual analogue scale (VAS). The IA injection mean VAS score and standard deviation were 38.9 ± 22.7 mm and 37.1 ± 22.4 mm, respectively, for the larger and standard-bore needles. The LB injection mean VAS score and standard deviation were 33.5 ± 22.8 mm and 35.1 ± 19.6 mm, respectively, for the larger and standard-bore needles. The data were analyzed with a paired t test (α = .05). No significant difference was found between the IA (P = .70) or LB injections (P = .73). The use of a larger-bore 27-gauge needle did not reduce pain on injection compared with the standard-bore 27-gauge needle.

  5. Anesthetics rapidly promote synaptogenesis during a critical period of brain development.

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    Mathias De Roo

    Full Text Available Experience-driven activity plays an essential role in the development of brain circuitry during critical periods of early postnatal life, a process that depends upon a dynamic balance between excitatory and inhibitory signals. Since general anesthetics are powerful pharmacological modulators of neuronal activity, an important question is whether and how these drugs can affect the development of synaptic networks. To address this issue, we examined here the impact of anesthetics on synapse growth and dynamics. We show that exposure of young rodents to anesthetics that either enhance GABAergic inhibition or block NMDA receptors rapidly induce a significant increase in dendritic spine density in the somatosensory cortex and hippocampus. This effect is developmentally regulated; it is transient but lasts for several days and is also reproduced by selective antagonists of excitatory receptors. Analyses of spine dynamics in hippocampal slice cultures reveals that this effect is mediated through an increased rate of protrusions formation, a better stabilization of newly formed spines, and leads to the formation of functional synapses. Altogether, these findings point to anesthesia as an important modulator of spine dynamics in the developing brain and suggest the existence of a homeostatic process regulating spine formation as a function of neural activity. Importantly, they also raise concern about the potential impact of these drugs on human practice, when applied during critical periods of development in infants.

  6. Sevoflurane Induces DNA Damage Whereas Isoflurane Leads to Higher Antioxidative Status in Anesthetized Rats

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    Thalita L. A. Rocha

    2015-01-01

    Full Text Available Taking into account that there are controversial antioxidative effects of inhalational anesthetics isoflurane and sevoflurane and absence of comparison of genotoxicity of both anesthetics in animal model, the aim of this study was to compare DNA damage and antioxidant status in Wistar rats exposed to a single time to isoflurane or sevoflurane. The alkaline single-cell gel electrophoresis assay (comet assay was performed in order to evaluate DNA damage in whole blood cells of control animals (unexposed; n = 6 and those exposed to 2% isoflurane (n = 6 or 4% sevoflurane (n = 6 for 120 min. Plasma antioxidant status was determined by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay. There was no statistically significant difference between isoflurane and sevoflurane groups regarding hemodynamic and temperature variables (P > 0.05. Sevoflurane significantly increased DNA damage compared to unexposed animals (P = 0.02. In addition, Wistar rats anesthetized with isoflurane showed higher antioxidative status (MTT than control group (P = 0.019. There were no significant differences in DNA damage or antioxidant status between isoflurane and sevoflurane groups (P > 0.05. In conclusion, our findings suggest that, in contrast to sevoflurane exposure, isoflurane increases systemic antioxidative status, protecting cells from DNA damage in rats.

  7. Risk Management Status of Waste Anesthetic Gases Using ECRI Institute Standards

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    S Asefzadeh

    2012-11-01

    Full Text Available Background: The aim of this study was assessment the risk management status of waste anesthetic gases in academicals hospitals in Iran to prevent from harmful effects of these gases on employees' health.Methods: A descriptive-analytic study was designed in 2011. Standard structured checklist developed by ECRI institute (Emergency Care Research Institute was applied. Checklists were filled onsite through direct observation and interviews with anesthesia personnel in 46 operating rooms at 4 hospitals from all of the hospitals under affiliation of Isfahan University of Medical Sciences. These hospitals were selected based on the number of surgical beds.Results: Total means score of WAGs risk management status was 1.72 from the scale of 3. In the studied operating rooms, only 28% complied with predetermined standards, 16% needed improvement and 56% had no compliance. Total mean scores of compliance in planning, training and evaluation and monitoring of waste anesthetic gases were weak and equipment and work activity was at medium level.Conclusion: The risk management status of waste anesthetic gases in the hospitals to be weak, therefore operating room personnel are exposed to medium to high level of these gases. The hospital mangers should prepare and apply scavenging equipment, development of control program, quality improvement, risk management and maintenance of anesthesia equipment. Finally, ongoing monitoring and evaluation, education to personnel and modification of policy and procedures and improvement of work activities should be considered.

  8. Effects of Injectable Anesthetic Combinations on Left Ventricular Function and Cardiac Morphology in Sprague–Dawley Rats

    OpenAIRE

    Sabatini, Carla F; O'Sullivan, M. Lynne; Valcour, James E.; Sears, William; Johnson, Ron J

    2013-01-01

    Novel anesthetic agents or combinations may provide superior general anesthesia for echocardiography in rodents with the potential for reduced adverse effects. This study sought to characterize the effects of 3 injectable anesthetics on left ventricular (LV) systolic function and cardiac morphology in healthy male and female rats. Rats underwent echocardiographic assessment after general anesthesia via pentobarbital or combinations of ketamine and medetomidine (KME) and ketamine and midazolam...

  9. Super obese 33-week parturient undergoing an urgent laparoscopic bowel resection: A case report and review of anesthetic implications

    Directory of Open Access Journals (Sweden)

    Yury Khelemsky

    2011-01-01

    Full Text Available Approximately two percent of women undergo non-obstetric surgery during their pregnancies. The following case report describes the anesthetic management of a super obese parturient in her third trimester of pregnancy undergoing urgent laparoscopic (converted to open bowel resection. Such a case, which has not been previously reported, has multiple clinical implications for both mother and fetus and was further complicated by super obesity (BMI>50 and laparoscopy. The anesthetic implications for this patient population are reviewed.

  10. ANESTHETIC MANAGEMENT OF ATONIC POST - PARTUM HEMORRHAGE WITH HEMORRHAGIC SHOCK AND IMPENDING CARDIAC ARREST FOR EMERGENCY PERIPARTUM HYSTERECTOMY

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    Ravishankar

    2015-07-01

    Full Text Available Post - partum hemorrhagic complication is a critical situation for an anesthesiologist, which requires timely and skillful anesthetic management. A massive post - partum bleeding leading to severe hypovolemic shock may result in life threatening cardio - pulmonary arrest. Here is a case report of 25 year old with atonic post - partum hemorrhage resulting in hypovolemic shock & impending cardiac arrest and successful anesthetic management for emergency peripartum hysterectomy to save the life of the patient.

  11. Anesthetic drug midazolam inhibits cardiac human ether-à-go-go-related gene channels: mode of action

    Directory of Open Access Journals (Sweden)

    Vonderlin N

    2015-02-01

    Full Text Available Nadine Vonderlin,1 Fathima Fischer,1 Edgar Zitron,1,2 Claudia Seyler,1 Daniel Scherer,1 Dierk Thomas,1,2 Hugo A Katus,1,2 Eberhard P Scholz1 1Department of Internal Medicine III, University Hospital Heidelberg, 2German Centre for Cardiovascular Research, Partner Site Heidelberg/Mannheim, Heidelberg, Germany Abstract: Midazolam is a short-acting benzodiazepine that is in wide clinical use as an anxiolytic, sedative, hypnotic, and anticonvulsant. Midazolam has been shown to inhibit ion channels, including calcium and potassium channels. So far, the effects of midazolam on cardiac human ether-à-go-go-related gene (hERG channels have not been analyzed. The inhibitory effects of midazolam on heterologously expressed hERG channels were analyzed in Xenopus oocytes using the double-electrode voltage clamp technique. We found that midazolam inhibits hERG channels in a concentration-dependent manner, yielding an IC50 of 170 µM in Xenopus oocytes. When analyzed in a HEK 293 cell line using the patch-clamp technique, the IC50 was 13.6 µM. Midazolam resulted in a small negative shift of the activation curve of hERG channels. However, steady-state inactivation was not significantly affected. We further show that inhibition is state-dependent, occurring within the open and inactivated but not in the closed state. There was no frequency dependence of block. Using the hERG pore mutants F656A and Y652A we provide evidence that midazolam uses a classical binding site within the channel pore. Analyzing the subacute effects of midazolam on hERG channel trafficking, we further found that midazolam does not affect channel surface expression. Taken together, we show that the anesthetic midazolam is a low-affinity inhibitor of cardiac hERG channels without additional effects on channel surface expression. These data add to the current understanding of the pharmacological profile of the anesthetic midazolam. Keywords: midazolam, anesthetics, human ether

  12. Modelling the Volatility-Return Trade-off when Volatility may be Nonstationary

    DEFF Research Database (Denmark)

    Dahl, Christian Møller; Iglesias, Emma M.

    In this paper a new GARCH-M type model, denoted the GARCH-AR, is proposed. In particular, it is shown that it is possible to generate a volatility-return trade-off in a regression model simply by introducing dynamics in the standardized disturbance process. Importantly, the volatility in the GARCH...

  13. Volatility Spillover and Multivariate Volatility Impulse Response Analysis of GFC News Events

    NARCIS (Netherlands)

    D.E. Allen (David); M.J. McAleer (Michael); R.J. Powell (Robert); A.K. Singh (Abhay)

    2016-01-01

    textabstractThis paper applies two measures to assess spillovers across markets: the Diebold Yilmaz (2012) Spillover Index and the Hafner and Herwartz (2006) analysis of multivariate GARCH models using volatility impulse response analysis. We use two sets of data, daily realized volatility estimates

  14. Implicit Volatility versus Statistical Volatility: an Exercise Using Options and Telemar S.A. Stock

    Directory of Open Access Journals (Sweden)

    Marcelo Savino Portugal

    2004-06-01

    Full Text Available The main goal this article was to find the best way of making forecast about future volatility using implicit or statistic forecast. The work is based on Telemar S.A. shares data from 21/09/1998 to 21/10/2002 and Telemar S.A. shares data from 2/10/2000 to 21/10/2002. The implicit volatility was obtained using back-out procedure from the Black-Scholes model. The statistics forecasts were obtained using weighted moving average models, GARCH, EGARCH and FIGARCH models. The Wald statistic shows that EGARCH and FIGARCH models are efficient and are not biased forecasts for Telemar S.A. absolute variation between t and t + 1. The volatility evaluation during the maturity time of an option, rejects the hypothesis that implicit volatility is the best forecast to future volatility and the Wald statistic show that FIGARCH model is an efficient and not biased forecast.

  15. Combination of volatile and non-volatile functions in a single memory cell and its scalability

    Science.gov (United States)

    Kim, Hyungjin; Hwang, Sungmin; Lee, Jong-Ho; Park, Byung-Gook

    2017-04-01

    A single memory cell which combines volatile memory and non-volatile memory functions has been demonstrated with an independent asymmetric dual-gate structure. Owing to the second gate whose dielectric is composed of oxide/nitride/oxide layers, floating body effect was observed even on a fully depleted silicon-on-insulator device and the non-volatile memory function was measured. In addition, read retention characteristics of the volatile memory function depending on the non-volatile memory state were evaluated and analyzed. Further scalability in body thickness was also verified through simulation studies. These results indicate that the proposed device is a promising candidate for high-density embedded memory applications.

  16. Modeling and forecasting petroleum futures volatility

    Energy Technology Data Exchange (ETDEWEB)

    Sadorsky, Perry [York Univ., Schulich School of Business, Toronto, ON (Canada)

    2006-07-15

    Forecasts of oil price volatility are important inputs into macroeconometric models, financial market risk assessment calculations like value at risk, and option pricing formulas for futures contracts. This paper uses several different univariate and multivariate statistical models to estimate forecasts of daily volatility in petroleum futures price returns. The out-of-sample forecasts are evaluated using forecast accuracy tests and market timing tests. The TGARCH model fits well for heating oil and natural gas volatility and the GARCH model fits well for crude oil and unleaded gasoline volatility. Simple moving average models seem to fit well in some cases provided the correct order is chosen. Despite the increased complexity, models like state space, vector autoregression and bivariate GARCH do not perform as well as the single equation GARCH model. Most models out perform a random walk and there is evidence of market timing. Parametric and non-parametric value at risk measures are calculated and compared. Non-parametric models outperform the parametric models in terms of number of exceedences in backtests. These results are useful for anyone needing forecasts of petroleum futures volatility. (author)

  17. A bacterial volatile signal for biofilm formation

    Science.gov (United States)

    Chen, Yun; Gozzi, Kevin; Chai, Yunrong

    2015-01-01

    Bacteria constantly monitor the environment they reside in and respond to potential changes in the environment through a variety of signal sensing and transduction mechanisms in a timely fashion. Those signaling mechanisms often involve application of small, diffusible chemical molecules. Volatiles are a group of small air-transmittable chemicals that are produced universally by all kingdoms of organisms. Past studies have shown that volatiles can function as cell-cell communication signals not only within species, but also cross-species. However, little is known about how the volatile-mediated signaling mechanism works. In our recent study (Chen, et al. mBio (2015), 6: e00392-15), we demonstrated that the soil bacterium Bacillus subtilis uses acetic acid as a volatile signal to coordinate the timing of biofilm formation within physically separated cells in the community. We also showed that the bacterium possesses an intertwined gene network to produce, secrete, sense, and respond to acetic acid, in stimulating biofilm formation. Interestingly, many of those genes are highly conserved in other bacterial species, raising the possibility that acetic acid may act as a volatile signal for cross-species communication.

  18. Optimal directional volatile transport in retronasal olfaction.

    Science.gov (United States)

    Ni, Rui; Michalski, Mark H; Brown, Elliott; Doan, Ngoc; Zinter, Joseph; Ouellette, Nicholas T; Shepherd, Gordon M

    2015-11-24

    The ability of humans to distinguish the delicate differences in food flavors depends mostly on retronasal smell, in which food volatiles entrained into the airway at the back of the oral cavity are transported by exhaled air through the nasal cavity to stimulate the olfactory receptor neurons. Little is known whether food volatiles are preferentially carried by retronasal flow toward the nasal cavity rather than by orthonasal flow into the lung. To study the differences between retronasal and orthonasal flow, we obtained computed tomography (CT) images of the orthonasal airway from a healthy human subject, printed an experimental model using a 3D printer, and analyzed the flow field inside the airway. The results show that, during inhalation, the anatomical structure of the oropharynx creates an air curtain outside a virtual cavity connecting the oropharynx and the back of the mouth, which prevents food volatiles from being transported into the main stream toward the lung. In contrast, during exhalation, the flow preferentially sweeps through this virtual cavity and effectively enhances the entrainment of food volatiles into the main retronasal flow. This asymmetrical transport efficiency is also found to have a nonmonotonic Reynolds number dependence: The asymmetry peaks at a range of an intermediate Reynolds number close to 800, because the air curtain effect during inhalation becomes strongest in this range. This study provides the first experimental evidence, to our knowledge, for adaptations of the geometry of the human oropharynx for efficient transport of food volatiles toward the olfactory receptors in the nasal cavity.

  19. A bacterial volatile signal for biofilm formation

    Directory of Open Access Journals (Sweden)

    Yun Chen

    2015-09-01

    Full Text Available Bacteria constantly monitor the environment they reside in and respond to potential changes in the environment through a variety of signal sensing and transduction mechanisms in a timely fashion. Those signaling mechanisms often involve application of small, diffusible chemical molecules. Volatiles are a group of small air-transmittable chemicals that are produced universally by all kingdoms of organisms. Past studies have shown that volatiles can function as cell-cell communication signals not only within species, but also cross-species. However, little is known about how the volatile-mediated signaling mechanism works. In our recent study (Chen, et al. mBio (2015, 6: e00392-15, we demonstrated that the soil bacterium Bacillus subtilis uses acetic acid as a volatile signal to coordinate the timing of biofilm formation within physically separated cells in the community. We also showed that the bacterium possesses an intertwined gene network to produce, secrete, sense, and respond to acetic acid, in stimulating biofilm formation. Interestingly, many of those genes are highly conserved in other bacterial species, raising the possibility that acetic acid may act as a volatile signal for cross-species communication.

  20. Optimal directional volatile transport in retronasal olfaction

    Science.gov (United States)

    Ni, Rui; Michalski, Mark H.; Brown, Elliott; Doan, Ngoc; Zinter, Joseph; Ouellette, Nicholas T.; Shepherd, Gordon M.

    2015-01-01

    The ability of humans to distinguish the delicate differences in food flavors depends mostly on retronasal smell, in which food volatiles entrained into the airway at the back of the oral cavity are transported by exhaled air through the nasal cavity to stimulate the olfactory receptor neurons. Little is known whether food volatiles are preferentially carried by retronasal flow toward the nasal cavity rather than by orthonasal flow into the lung. To study the differences between retronasal and orthonasal flow, we obtained computed tomography (CT) images of the orthonasal airway from a healthy human subject, printed an experimental model using a 3D printer, and analyzed the flow field inside the airway. The results show that, during inhalation, the anatomical structure of the oropharynx creates an air curtain outside a virtual cavity connecting the oropharynx and the back of the mouth, which prevents food volatiles from being transported into the main stream toward the lung. In contrast, during exhalation, the flow preferentially sweeps through this virtual cavity and effectively enhances the entrainment of food volatiles into the main retronasal flow. This asymmetrical transport efficiency is also found to have a nonmonotonic Reynolds number dependence: The asymmetry peaks at a range of an intermediate Reynolds number close to 800, because the air curtain effect during inhalation becomes strongest in this range. This study provides the first experimental evidence, to our knowledge, for adaptations of the geometry of the human oropharynx for efficient transport of food volatiles toward the olfactory receptors in the nasal cavity. PMID:26553982

  1. Dynamic Factor Models for the Volatility Surface

    DEFF Research Database (Denmark)

    van der Wel, Michel; Ozturk, Sait R.; Dijk, Dick van

    The implied volatility surface is the collection of volatilities implied by option contracts for different strike prices and time-to-maturity. We study factor models to capture the dynamics of this three-dimensional implied volatility surface. Three model types are considered to examine desirable...... features for representing the surface and its dynamics: a general dynamic factor model, restricted factor models designed to capture the key features of the surface along the moneyness and maturity dimensions, and in-between spline-based methods. Key findings are that: (i) the restricted and spline......-based models are both rejected against the general dynamic factor model, (ii) the factors driving the surface are highly persistent, (iii) for the restricted models option Delta is preferred over the more often used strike relative to spot price as measure for moneyness....

  2. Removal Of Volatile Impurities From Copper Concentrates

    Energy Technology Data Exchange (ETDEWEB)

    Winkel, L.; Schuler, A.; Frei, A.; Sturzenegger, M.

    2005-03-01

    To study the removal of volatile impurities from two different copper concentrates they have been heated on a thermo balance to temperatures between 900 and 1500 C. This sample treatment revealed that both concentrates undergo strong weight losses at 500 and 700 C. They were attributed to the removal of sulfur. Elemental analyses of the residues by ICP spectrometry have shown that the thermal treatment efficiently removes the volatile impurities. Already below 900 C most of the arsenic is removed by evaporation, the largest fraction of lead and zinc is removed in the temperature interval of 1300-1500 C. It was observed that quartz in the concentrate leads to the formation of a silicon-enriched phase besides a metal rich sulfide phase. The former is interpreted as an early stage of a silicate slag. Elemental analysis showed that the formation of this distinct slag phase does not hinder the efficient removal of volatile impurities. (author)

  3. Volatility jumps and their economic determinants

    DEFF Research Database (Denmark)

    Caporin, Massimiliano; Rossi, Eduardo; Santucci de Magistris, Paolo

    that there is a positive probability of jumps in volatility. A common factor in the volatility jumps is shown to be related to a set of financial covariates (such as variance risk premium, S&P500 volume, credit-default swap, and federal fund rates). The credit-default swap on US banks and variance risk premium have...... predictive power on expected jump moves, thus confirming the common interpretation that sudden and large increases in equity volatility can be anticipated by credit deterioration of the US bank sector as well as changes in the market expectations of future risks. Finally, the model is extended to incorporate...... the credit-default swap and the variance risk premium in the dynamics of the jump size and intensity....

  4. Local anesthetic failure associated with inflammation: verification of the acidosis mechanism and the hypothetic participation of inflammatory peroxynitrite

    Directory of Open Access Journals (Sweden)

    Takahiro Ueno

    2008-11-01

    Full Text Available Takahiro Ueno1, Hironori Tsuchiya2, Maki Mizogami1, Ko Takakura11Department of Anesthesiology, Asahi University School of Dentistry, Mizuho, Gifu, Japan; 2Department of Dental Basic Education, Asahi University School of Dentistry, Mizuho, Gifu, JapanAbstract: The presence of inflammation decreases local anesthetic efficacy, especially in dental anesthesia. Although inflammatory acidosis is most frequently cited as the cause of such clinical phenomena, this has not been experimentally proved. We verified the acidosis mechanism by studying the drug and membrane lipid interaction under acidic conditions together with proposing an alternative hypothesis. Liposomes and nerve cell model membranes consisting of phospholipids and cholesterol were treated at different pH with lidocaine, prilocaine and bupivacaine (0.05%–0.2%, w/v. Their membrane-interactive potencies were compared by the induced-changes in membrane fluidity. Local anesthetics fluidized phosphatidylcholine membranes with the potency being significantly lower at pH 6.4 than at pH 7.4 (p < 0.01, supporting the acidosis theory. However, they greatly fluidized nerve cell model membranes even at pH 6.4 corresponding to inflamed tissues, challenging the conventional mechanism. Local anesthetics acted on phosphatidylserine liposomes, as well as nerve cell model membranes, at pH 6.4 with almost the same potency as that at pH 7.4, but not on phosphatidylcholine, phosphatidylethanolamine and sphingomyelin liposomes. Since the positively charged anesthetic molecules are able to interact with nerve cell membranes by ion-paring with anionic components like phosphatidylserine, tissue acidosis is not essentially responsible for the local anesthetic failure associated with inflammation. The effects of local anesthetics on nerve cell model membranes were inhibited by treating with peroxynitrite (50 μM, suggesting that inflammatory cells producing peroxynitrite may affect local anesthesia

  5. Local Volatility Calibration Using An Adjoint Proxy

    Directory of Open Access Journals (Sweden)

    Gabriel TURINICI

    2008-11-01

    Full Text Available We document the calibration of the local volatility in a framework similar to Coleman, Li and Verma. The quality of a surface is assessed through a functional to be optimized; the specificity of the approach is to separate the optimization (performed with any suitable optimization algorithm from the computation of the functional where we use an adjoint (as in L. Jiang et. al. to obtain an approximation; moreover our main calibration variable is the implied volatility (the procedure can also accommodate the Greeks. The procedure performs well on benchmarks from the literature and on FOREX data.

  6. Volatile compound formation during argan kernel roasting.

    Science.gov (United States)

    El Monfalouti, Hanae; Charrouf, Zoubida; Giordano, Manuela; Guillaume, Dominique; Kartah, Badreddine; Harhar, Hicham; Gharby, Saïd; Denhez, Clément; Zeppa, Giuseppe

    2013-01-01

    Virgin edible argan oil is prepared by cold-pressing argan kernels previously roasted at 110 degrees C for up to 25 minutes. The concentration of 40 volatile compounds in virgin edible argan oil was determined as a function of argan kernel roasting time. Most of the volatile compounds begin to be formed after 15 to 25 minutes of roasting. This suggests that a strictly controlled roasting time should allow the modulation of argan oil taste and thus satisfy different types of consumers. This could be of major importance considering the present booming use of edible argan oil.

  7. Effects of different general anesthetics on serum hemolysis and hepatic and muscular glycogenolysis in rats

    Directory of Open Access Journals (Sweden)

    E.F.A. Machado

    2009-11-01

    Full Text Available Anesthetics can affect the structure and biological function of tissues and systems differentially. The aim of the present study was to compare three injectable anesthetics generally used in experiments with animals in terms of the degree of hemolysis and glycogenolysis occurring after profound anesthesia. Twenty-four male Wistar rats (330-440 g were divided into three groups (N = 8: chloral hydrate (CH, ketamine + xylazine (KX, Zoletil 50® (zolazepam and tiletamine + xylazine (ZTX. After deep anesthesia, total blood was collected. The liver and white (WG and red gastrocnemius (RG muscles were also immediately removed. The degree of serum hemolysis was quantified on the basis of hemoglobin concentration (g/L. Hepatic and muscular glycogen concentrations (mmol/kg wet tissue were quantified by the phenol-sulfuric method. The CH and KX groups exhibited serum hemolysis (4.0 ± 2.2 and 1.9 ± 0.9 g/L, respectively; P < 0.05 compared to the ZTX group, which presented none. Only KX induced elevated glycogenolysis (mmol/kg wet tissue in the liver (86.9 ± 63.2 and in WG (18.7 ± 9.0 and RG (15.2 ± 7.2; P < 0.05. The CH and ZTX groups exhibited no glycogenolysis in the liver (164.4 ± 41.1 and 176.8 ± 54.4, respectively, WG (28.8 ± 4.4, 32.0 ± 6.5, respectively or RG (29.0 ± 4.9; 25.3 ± 8.6, respectively. Our data indicate that ZTX seems to be an appropriate general anesthetic for studies that seek to simultaneously quantify the concentration of glycogen and serum biochemical markers without interferences. ZTX is reasonably priced, found easily at veterinary markets, quickly induces deep anesthesia, and presents a low mortality rate.

  8. Effects of different general anesthetics on serum hemolysis and hepatic and muscular glycogenolysis in rats.

    Science.gov (United States)

    Machado, E F A; Normand, A C R; Nunes, L A S; Brenzikofer, R; Macedo, D V

    2009-11-01

    Anesthetics can affect the structure and biological function of tissues and systems differentially. The aim of the present study was to compare three injectable anesthetics generally used in experiments with animals in terms of the degree of hemolysis and glycogenolysis occurring after profound anesthesia. Twenty-four male Wistar rats (330-440 g) were divided into three groups (N = 8): chloral hydrate (CH), ketamine + xylazine (KX), Zoletil 50(R) (zolazepam and tiletamine) + xylazine (ZTX). After deep anesthesia, total blood was collected. The liver and white (WG) and red gastrocnemius (RG) muscles were also immediately removed. The degree of serum hemolysis was quantified on the basis of hemoglobin concentration (g/L). Hepatic and muscular glycogen concentrations (mmol/kg wet tissue) were quantified by the phenol-sulfuric method. The CH and KX groups exhibited serum hemolysis (4.0 +/- 2.2 and 1.9 +/- 0.9 g/L, respectively; P glycogenolysis (mmol/kg wet tissue) in the liver (86.9 +/- 63.2) and in WG (18.7 +/- 9.0) and RG (15.2 +/- 7.2; P glycogenolysis in the liver (164.4 +/- 41.1 and 176.8 +/- 54.4, respectively), WG (28.8 +/- 4.4, 32.0 +/- 6.5, respectively) or RG (29.0 +/- 4.9; 25.3 +/- 8.6, respectively). Our data indicate that ZTX seems to be an appropriate general anesthetic for studies that seek to simultaneously quantify the concentration of glycogen and serum biochemical markers without interferences. ZTX is reasonably priced, found easily at veterinary markets, quickly induces deep anesthesia, and presents a low mortality rate.

  9. Development of a behavioral assessment of craniofacial muscle pain in lightly anesthetized rats.

    Science.gov (United States)

    Ro, Jin Y; Capra, Norman; Masri, Radi

    2003-07-01

    In this study, a new behavioral assessment of craniofacial muscle pain in the lightly anesthetized rat is described. Intramuscular injections with algesic agents in lightly anesthetized rats evoked a characteristic ipsilateral hindpaw shaking behavior for several minutes similar to previously described orofacial pain-induced grooming behavior in awake rats (Neurosci Lett 103 (1989) 349, Pain 62 (1995) 295). Eighty-two male Sprague-Dawley rats were used in a series of experiments to study whether this behavior could serve as a valid measure of craniofacial muscle pain. First, we demonstrated that different algesic chemicals, mustard oil (20%), formalin (3%) or hypertonic saline (5%) injected in the mid-region of the masseter muscle effectively elicited the hindpaw shaking behavior. The behavior was only minimally evoked with vehicle injection. Repeated administrations of hypertonic saline, a short duration non-sensitizing algogen, demonstrated reproducibility of the assay. Second, we showed that the peak and overall magnitude of the shaking behavior evoked by injections with different concentrations of mustard oil (1 and 5%) changed in a concentration dependent manner. Finally, we showed that systemic administration of morphine sulfate (3 and 0.3 mg/kg, i.p.) dose dependently attenuated mustard oil induced hindpaw-shaking behavior. Lidocaine injected locally 5 min prior to mustard oil injection also significantly decreased the hindpaw shaking behavior. Based on these results we concluded that ipsilateral hindpaw shaking in lightly anesthetized rats is a stereotypical behavior evoked by noxious muscle stimulation and can be used as a reliable behavioral measure to assess craniofacial muscle pain.

  10. Differential Postoperative Effects of Volatile Anesthesia and Intraoperative Remifentanil Infusion in 7511 Thyroidectomy Patients

    Science.gov (United States)

    Jo, Jun-Young; Choi, Seong-Soo; Yi, Jung Min; Joo, Eun Young; Kim, Ji Hyun; Park, Se Ung; Sim, Ji-Hoon; Karm, Myong-Hwan; Ku, Seungwoo

    2016-01-01

    Abstract Although remifentanil is used widely by many clinicians during general anesthesia, there are recent evidences of opioid-induced hyperalgesia as an adverse effect. This study aimed to determine if intraoperative remifentanil infusion caused increased pain during the postoperative period in patients who underwent a thyroidectomy. A total of 7511 patients aged ≥ 20 years, who underwent thyroidectomy between January 2009 and December 2013 at the Asan Medical Center were retrospectively analyzed. Enrolled patients were divided into 2 groups: group N (no intraoperative remifentanil and only volatile maintenance anesthesia) and group R (intraoperative remifentanil infusion including total intravenous anesthesia and balanced anesthesia). Following propensity score matching analysis, 2582 patients were included in each group. Pain scores based on numeric rating scales (NRS) were compared between the 2 groups at the postoperative anesthetic care unit and at the ward until 3 days postoperation. Incidences of postoperative complications, such as nausea, itching, and shivering were also compared. The estimated NRS pain score on the day of surgery was 5.08 (95% confidence interval [CI] 4.97–5.19) in group N patients and 6.73 (95% CI 6.65–6.80) in group R patients (P < 0.001). There were no statistically significant differences in NRS scores on postoperative days 1, 2, and 3 between the 2 groups. Postoperative nausea was less frequent in group R (31.4%) than in group N (53.5%) (P < 0.001). However, the incidence of itching was higher in group R (4.3%) than in group N (0.7%) (P < 0.001). Continuous infusion of remifentanil during general anesthesia can cause higher intensity of postoperative pain and more frequent itching than general anesthesia without remifentanil infusion immediately after thyroidectomy. Considering the advantages and disadvantages of continuous remifentanil infusion, volatile anesthesia without opioid may be a good choice for minor

  11. Anesthetic Management of Urgent Cesarean Section with Undiagnosed Transposition of Great Arteries.

    Science.gov (United States)

    Yilmaz, Nurullah; Koksal, Ersin; Ozgen, Gokce Ultan; Ozen, Ersan; Dilek, Ahmet; Karakaya, Deniz; Ulger, Fatma

    2016-06-01

    We consider that general anesthesia will be an appropriate and safe method as regional methods could lead to significant time loss in the prevention or minimization of complications. High blockage required for regional anesthetic methods in pregnant women with TGA and the maintenance of hemodynamic stability may become difficult due to neuroaxial sympathectomy even if a successful neuroaxial block has been provided. Agents with minimal effect on cardiovascular functions should be preferred for anesthesia induction and maintenance and close hemodynamic monitoring should be done during intraoperative and postoperative periods.

  12. Anesthetic management of a parturient with Stiff person syndrome for urgent cesarean delivery.

    Science.gov (United States)

    Boettcher, B T; Muravyea, M; Kuo, C; Drexler, C; Pagel, P S

    2016-08-01

    Stiff person syndrome is a rare neurologic disorder with an estimated incidence of 1:1000000. The underlying pathophysiology is truncal and proximal limb muscle stiffness resulting from continuous co-contracture of agonist and antagonist muscle groups concomitant with superimposed episodic muscle spasms. Loss of gamma-aminobutyric acid-mediated inhibition creates chronic excitation manifested by tonic agonist-antagonist muscle contraction. To date, only three case reports referred indirectly to the anesthetic management of parturients with Stiff person syndrome. The authors describe their management of a parturient with Stiff person syndrome who underwent urgent cesarean delivery under epidural anesthesia.

  13. Can children undergoing ophthalmologic examinations under anesthesia be safely anesthetized without using an IV line?

    Directory of Open Access Journals (Sweden)

    Vigoda M

    2011-04-01

    Full Text Available Michael M Vigoda, Azeema Latiff, Timothy G Murray, Jacqueline L Tutiven, Audina M Berrocal, Steven GayerBascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USAPurpose: To document that with proper patient and procedure selection, children undergoing general inhalational anesthesia for ophthalmologic exams (with or without photos, ultrasound, laser treatment, peri-ocular injection of chemotherapy, suture removal, and/or replacement of ocular prosthesis can be safely anesthetized without the use of an intravenous (IV line. Children are rarely anesthetized without IV access placement. We performed a retrospective study to determine our incidence of IV access placement during examinations under anesthesia (EUA and the incidence of adverse events that required intraoperative IV access placement.Methods: Data collected from our operating room (OR information system includes but is not limited to diagnosis, anesthesiologist, surgeon, and location of IV catheter (if applicable, patient’s date of birth, actual procedure, and anesthesia/procedure times. We reviewed the OR and anesthetic records of children (>1 month and <10 years who underwent EUAs between January 1, 2003 and May 31, 2009. We determined the percentage of children who were anesthetized without IV access placement, as well as the incidence of any adverse events that required IV access placement, intraoperatively.Results: We analyzed data from 3196 procedures performed during a 77-month period. Patients’ ages ranged from 1 month to 9 years. Overall, 92% of procedures were performed without IV access placement. Procedure duration ranged from 1–39 minutes. Reasons for IV access placement included parental preference for antinausea medication and/or attending preference for IV access placement. No child who underwent anesthesia without an IV line had an intraoperative adverse event requiring insertion of an IV line.Conclusion: Our data suggest that for

  14. Development of transmucosal patch loaded with anesthetic and analgesic for dental procedures and in vivo evaluation

    Directory of Open Access Journals (Sweden)

    Nidhi M

    2016-06-01

    Full Text Available Malviya Nidhi,1 M Nagaraju Patro,1 Somisetty Kusumvalli,2 Vemula Kusumdevi1 1Department of Pharmaceutics, Al-Ameen College of Pharmacy, 2Department of Endodontics and Conservative Dentistry, Sri Rajiv Gandhi College of Dental Sciences, Bengaluru, Karnataka, India Abstract: Most of the dental surgeries require preoperative anesthetic and postoperative analgesic for painless procedures. A multidrug transmucosal drug delivery system loaded with lignocaine (Lig base for immediate release and solid lipid nanoparticles (SLNs of diclofenac (Dic diethylamine for prolonged release was developed. SLNs were prepared by solvent emulsion–evaporation method with Precirol ATO 5 and Geleol as lipids and Pluronic F 68 as surfactant and optimized with Box–Behnken design for particle size and entrapment efficiency. SLNs were incorporated into the transmucosal patch (TP prepared with hydroxypropyl cellulose-LF (HPC-LF and with a backing layer of ethyl cellulose. Optimized SLNs and TP were characterized for Fourier transform infrared spectrophotometry, differential scanning calorimetry, scanning electron microscopy, X-ray diffraction, in vitro release, ex vivo permeation through porcine buccal mucosa, Caco-2 permeability, and residual solvent analysis by gas chromatography. The TP was also evaluated for swelling index, in vitro residence time, tensile strength, and mucoadhesive strength. Preclinical pharmacokinetic, pharmacodynamic, and histopathological studies by application of TP on the gingiva of New Zealand rabbits were carried out. Particle size and entrapment efficiency of the optimized SLN “S8” were determined as 98.23 nm and 84.36%, respectively. The gingival crevicular fluid and tissue concentrations were greater than plasma concentrations with increase in Cmax and area under the curve (AUC of Lig and Dic when compared to the control group. Pain perception by needle prick showed prolonged combined anesthetic and analgesic effect. The developed TP

  15. Anesthetic implications of total anomalous systemic venous connection to left atrium with left isomerism

    Directory of Open Access Journals (Sweden)

    Parimala Prasanna Simha

    2012-01-01

    Full Text Available Total anomalous systemic venous connection (TASVC to the left atrium (LA is a rare congenital anomaly. An 11-year-old girl presented with complaints of palpitations and cyanosis. TASVC with left isomerism and noncompaction of LV was diagnosed after contrast echocardiogram and computed tomography angiogram. The knowledge of anatomy and pathophysiology is essential for the successful management of these cases. Anesthetic concerns in this case were polycythemia, paradoxical embolism and rhythm abnormalities. The patient was successfully operated by rerouting the systemic venous connection to the right atrium.

  16. Development of transmucosal patch loaded with anesthetic and analgesic for dental procedures and in vivo evaluation

    Science.gov (United States)

    Nidhi, Malviya; Patro, M Nagaraju; Kusumvalli, Somisetty; Kusumdevi, Vemula

    2016-01-01

    Most of the dental surgeries require preoperative anesthetic and postoperative analgesic for painless procedures. A multidrug transmucosal drug delivery system loaded with lignocaine (Lig) base for immediate release and solid lipid nanoparticles (SLNs) of diclofenac (Dic) diethylamine for prolonged release was developed. SLNs were prepared by solvent emulsion–evaporation method with Precirol ATO 5 and Geleol as lipids and Pluronic F 68 as surfactant and optimized with Box–Behnken design for particle size and entrapment efficiency. SLNs were incorporated into the transmucosal patch (TP) prepared with hydroxypropyl cellulose-LF (HPC-LF) and with a backing layer of ethyl cellulose. Optimized SLNs and TP were characterized for Fourier transform infrared spectrophotometry, differential scanning calorimetry, scanning electron microscopy, X-ray diffraction, in vitro release, ex vivo permeation through porcine buccal mucosa, Caco-2 permeability, and residual solvent analysis by gas chromatography. The TP was also evaluated for swelling index, in vitro residence time, tensile strength, and mucoadhesive strength. Preclinical pharmacokinetic, pharmacodynamic, and histopathological studies by application of TP on the gingiva of New Zealand rabbits were carried out. Particle size and entrapment efficiency of the optimized SLN “S8” were determined as 98.23 nm and 84.36%, respectively. The gingival crevicular fluid and tissue concentrations were greater than plasma concentrations with increase in Cmax and area under the curve (AUC) of Lig and Dic when compared to the control group. Pain perception by needle prick showed prolonged combined anesthetic and analgesic effect. The developed TP loaded with Lig base and Dic diethylamine-SLNs exhibited immediate and complete permeation with tissue accumulation of Lig followed by controlled prolonged release and tissue accumulation of Dic at the site of application. Thus, it could be anticipated from the in vivo studies that the

  17. Neonatal pain control and neurologic effects of anesthetics and sedatives in preterm infants.

    Science.gov (United States)

    McPherson, Christopher; Grunau, Ruth E

    2014-03-01

    Preclinical and clinical studies have demonstrated the adverse consequences of untreated pain and stress on brain development in the preterm infant. Sucrose has widely been implemented as standard therapy for minor procedural pain. Anesthetics are commonly utilized in preterm infants during major surgery. Pharmacologic agents (benzodiazepines and opioids) have been examined in clinical trials of preterm infants requiring invasive mechanical ventilation. Controversy exists regarding the safety and long-term impact of these interventions. Ongoing multidisciplinary research will help define the impact of these agents and identify potential alternative therapies.

  18. General anesthetic and the risk of dementia in elderly patients: current insights

    Directory of Open Access Journals (Sweden)

    Hussain M

    2014-09-01

    Full Text Available Maria Hussain,1 Miles Berger,2 Roderic G Eckenhoff,3 Dallas P Seitz1 1Division of Geriatric Psychiatry, Department of Psychiatry, Queen’s University; 2Anesthesiology Department, Duke University Medical Center, Durham, NC, USA; 3Department of Anesthesiology and Critical Care, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA Abstract: In this review, we aim to provide clinical insights into the relationship between surgery, general anesthesia (GA, and dementia, particularly Alzheimer’s disease (AD. The pathogenesis of AD is complex, involving specific disease-linked proteins (amyloid-beta [Aß] and tau, inflammation, and neurotransmitter dysregulation. Many points in this complex pathogenesis can potentially be influenced by both surgery and anesthetics. It has been demonstrated in some in vitro, animal, and human studies that some anesthetics are associated with increased aggregation and oligomerization of Aß peptide and enhanced accumulation and hyperphosphorylation of tau protein. Two neurocognitive syndromes that have been studied in relation to surgery and anesthesia are postoperative delirium and postoperative cognitive dysfunction, both of which occur more commonly in older adults after surgery and anesthesia. Neither the route of anesthesia nor the type of anesthetic appears to be significantly associated with the development of postoperative delirium or postoperative cognitive dysfunction. A meta-analysis of case-control studies found no association between prior exposure to surgery utilizing GA and incident AD (pooled odds ratio =1.05, P=0.43. The few cohort studies on this topic have shown varying associations between surgery, GA, and AD, with one showing an increased risk, and another demonstrating a decreased risk. A recent randomized trial has shown that patients who received sevoflurane during spinal surgery were more likely to have progression of preexisting mild cognitive impairment compared to

  19. Evaluation of the anesthetic effects of MS222 in the adult Mexican axolotl (Ambystoma mexicanum

    Directory of Open Access Journals (Sweden)

    Zullian C

    2016-01-01

    Full Text Available Chiara Zullian,1 Aurore Dodelet-Devillers,1 Stéphane Roy,2 Pascal Vachon1 1Département de Biomédecine Vétérinaire, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, 2Département de Stomatologie, Faculté de Médecine Dentaire, Montréal, Québec, Canada Abstract: The Mexican axolotl (Ambystoma mexicanum is a unique research model in several fields of medicine, where surgical and invasive procedures may be required. As yet, little is known about the efficacy of MS222 (tricaine methanesulfonate, which is the most commonly used anesthetic agent in amphibians. The main objectives of this study were to evaluate the anesthetic effects and physiological changes in adult axolotls following a 20-minute immersion bath, containing progressive MS222 concentrations starting at 0.1%. Depth of anesthesia and physiological changes were evaluated every 15 minutes post-MS222 exposure with the following parameters: righting behavior, withdrawal reflex, acetic acid test response, heart rate, and blood oxygen saturation, as well as cloacal and body surface temperatures. A 20-minute exposure in a 0.1% MS222 immersion bath (n=6 animals had no anesthetic effects on adult axolotls after 20 minutes of exposure. With a 0.2% MS222 solution, all axolotls (n=9 were deeply anesthetized at 15 minutes, and 80% were still unresponsive at 30 minutes postexposure. Blood oxygen saturation and heart rate were slightly, but significantly, increased when compared with the baseline value and remained stable up to recovery. There was no significant increase in surface and cloaca temperatures, compared with baseline. With the 0.4% MS222 solution, the duration of anesthesia lasted for 90 minutes to at least 120 minutes (n=3 animals and this concentration was deemed too high. In conclusion, a 20-minute immersion bath with 0.2% MS222 may be used for short procedures (15–30 minutes requiring anesthesia of adult axolotls. Keywords: Ambystoma mexicanum

  20. Adverse reactions following administration of an ionic iodinated contrast media in anesthetized dogs.

    Science.gov (United States)

    Vance, Amanda; Nelson, Matthew; Hofmeister, Erik H

    2012-01-01

    This retrospective study was conducted to identify hemodynamic alterations associated with the administration of an ionic iodinated contrast media in dogs. Case records of 49 dogs that were anesthetized for computed tomography scanning were reviewed. Values for heart rate (HR) and direct arterial pressure were obtained. Overall, 37% of dogs had a ≥20% change in either HR or systolic arterial pressure from baseline values. Four dogs (8%) became tachycardic and two dogs (4%) became bradycardic. Eight dogs (16%) became hypertensive and two dogs (4%) became hypotensive. A significant proportion of dogs experienced changes in HR and blood pressure following IV administration of an ionic iodinated contrast media under general anesthesia.

  1. Anesthetic management in a pediatric patient with Noonan syndrome, hypopituitarism and hypothyroidism: A case report

    Directory of Open Access Journals (Sweden)

    Abdulkadir Yektaş

    2013-06-01

    Full Text Available Noonan syndrome is a genetically transmitted autosomaldominant disorder characterized by various anatomicanomalies and pathophysiologic derangements. Associatedanomalies include hyperthelorism, ptosis, micrognathia,downward sloping palpebral fissures, low-set ears,abnormal helix of ear, deeply grooved philtrum, short and/or webbed neck, low hairline and cervical vertebral anomalies.Patients with Noonan syndrome are known to presentwith challenging airways. Tracheal intubation can bedifficult because of airway and cervical vertebral anomaliesand bag mask ventilation may be difficult because ofasymmetrical face. We present a case of anesthetic managementfor Noonan syndrome. J Clin Exp Invest 2013;4 (2: 238-241Key words: Anesthesia, general, noonan syndrome, airwaymanagement

  2. Cardiovascular effects of ritodrine are blocked by metoprolol in the anesthetized dog.

    Science.gov (United States)

    Gerritse, R; Reuwer, P J; Pinas, I M; Beijer, H J; Charbon, G A; Haspels, A A

    1985-11-01

    Inhibition of ritodrine-induced cardiac and peripheral vascular effects by the beta 1-adrenergic blocker metoprolol, was studied by electromagnetic flow measurements in anesthetized dogs. As expected, metoprolol inhibited the ritodrine-induced/increased cardiac workload and heart rate. Metoprolol also inhibited ritodrine-induced peripheral vasodilation. This leads to questions about the cardiac beta 1-adrenergic selectivity of metoprolol. Regarding earlier studies showing no interference in labor inhibition, the combination of ritodrine and metoprolol might be useful in treatment of preterm labor, while economizing cardiovascular performance centrally as well as peripherally.

  3. Anesthetic management of a patient with Bartter’s syndrome: A case report

    Directory of Open Access Journals (Sweden)

    Harun Aydoğan

    2012-09-01

    Full Text Available Bartter’s syndrome is a rare disorder characterized bysevere hypochloremic metabolic alkalosis, hypokalemia,hyponatremia, hyperaldosteronism, elevation in plasmarenin activity and insensitivity to angiotensin II. Electrolyteimbalances such as hypomagnesemia, hyponatremiamight make anesthetic management difficult in Barttersyndrome. A 4 years old patient underwent surgery foringuinal hernia with caudal anesthesia using bupivacaine0.25%. In this case report, it was aimed to discuss the anestheticmanagement of a patient with Bartter syndrome.Key words: Regional anesthesia, Bartter syndrome, inguinalhernia surgery, pediatric anesthesia

  4. Point mutations at the local anesthetic receptor site modulate the state-dependent block of rat Na v1.4 sodium channels by pyrazoline-type insecticides.

    Science.gov (United States)

    Silver, Kristopher S; Soderlund, David M

    2007-05-01

    Pyrazoline-type insecticides (PTIs) selectively block sodium channels at membrane potentials that promote slow sodium channel inactivation and are proposed to interact with a site that overlaps the local anesthetic (LA) receptor site. Mutagenesis studies identified two amino acid residues in the S6 segment of homology domain IV (Phe-1579 and Tyr-1586 in the rat Na(v)1.4 sodium channel) as principal elements of the LA receptor. To test the hypothesis that PTIs bind to the LA receptor, we constructed mutated Na(v)1.4/F1579A and Na(v)1.4/Y1586A cDNAs, expressed native and mutated channels in Xenopus oocytes, and examined the effects of these mutations on channel block by three PTIs (indoxacarb, its bioactivation product DCJW, and RH3421) by two-electrode voltage clamp. DCJW and RH3421 had no effect on Na(v)1.4 channels held at -120mV but caused a slowly developing block upon depolarization to -30mV. Estimated IC(50) values following 15min of exposure were 1 and 4muM for DCJW and RH3421, respectively. Indoxacarb failed to block Na(v)1.4 channels under all experimental conditions. Sensitivity to block by DCJW and RH3421 at -30mV was significantly reduced in Na(v)1.4/F1579A channels, a finding that is consistent with the impact of this mutation on drug binding. In contrast to its effect on drug binding, the Y1586A mutation increased the sensitivity of Na(v)1.4 channels held at -30mV to all three compounds, conferring modest sensitivity to indoxacarb and increasing sensitivity to DCJW and RH3421 by 58- and 16-fold, respectively. These results provide direct evidence for the action of PTIs at the LA receptor.

  5. 全身麻醉药在脊髓内的作用机制%Subcortical mechanisms of general anesthetics

    Institute of Scientific and Technical Information of China (English)

    杨静; 张宏

    2008-01-01

    The spinal cord plays an important role in two general anesthetic end-points: analgesia and immobility in response to a noxious stimulus. The spinal components that may contribute to anesthetic actions include the central termination of sensory primary afferent neurons, interneurones and the cell bodies and initial axon segments of motor neurons, which are contained in dorsal horn and ventral horn respectively. Different general anesthetics have both presynaptic and postsynaptic effects to produce analgesia and immobility via multitude of cellular and subcellular sites identified as potential targets of anaesthetic action, such as diverse ligand-gated ion channels etc. This review will focus on anesthetic targets and molecular mechanisms mediated analgesia and immobility of general anesthetics in spinal cord.%脊髓是全身麻醉药抑制伤害性刺激体动反应和抗伤害效应的重要作用部位,含有不同配体门控离子受体等多个可能介导麻醉效应的靶点.不同药物在脊髓内经各自特异靶点通过多种分子机制发挥作用.现就全身麻醉药制动和镇痛效应在脊髓内的作用位点和分子机制作一综述.

  6. Influence of general anesthetics on brain development%全身麻醉药对脑发育的影响

    Institute of Scientific and Technical Information of China (English)

    蒋燕; 陈萍

    2008-01-01

    The mortality of neonatal anesthesia is decreasing with the development of anestheisia. Pharmacological blockade of Nmethyl-D-aspartate (NMDA) type glutamate receptors or over stimulation of γ-aminobutyric acid type A receptors has been reported to induce neuron apoptosis in the period of brain peak development. In view of the mechanisms of general anesthetics on central nervous system, the influence of anesthetic agents on brain development becomes the researching focus. Clarifying the mechanisms of anesthetics affecting brain development is very important for the rational use of anesthetics in neonates, as well as for the exploitation of new anesthetics.%随着麻醉领域的不断发展,新生儿麻醉的死亡率明显下降.一系列的研究表明,在脑发育高峰期,药物性阻断N-甲基-D-天(门)冬氨酸受体或过度激动γ-氨基丁酸A型受体会诱发神经细胞凋亡.鉴于全麻药在中枢神经系统的作用机制,麻醉药物对脑发育的影响成为人们研究的热点,其机制的阐明可能对新生儿麻醉用药的合理选用及新药的开发具有指导意义.

  7. Research Progress in Safety of Fish Anesthetics%鱼用麻醉剂安全性研究进展

    Institute of Scientific and Technical Information of China (English)

    吕书为; 雷红涛; 孙远明

    2012-01-01

    鱼用麻醉剂能有效降低鱼类长途运输过程中的伤亡率,已在某些国家渔业生产中广泛应用,但其残留及安全性问题一直受到关注。目前有关鱼用麻醉剂的综述很少,为此本文对鱼用麻醉剂的类别、毒理学研究结果、麻醉剂在鱼体中积累与净化的影响因素等进行了综述,并对我国鱼用麻醉剂的使用和管理提出了部分建议。%Fish anesthetics can efficiently reduce the casualty rate of fish during long-distance transportation.Therefore,fish anesthetics have been widely used in fishery production in some countries.However,the residues of such anesthetics and the safety of fish have gained public concerns.In the present paper,the toxicology and the factors affecting accumulation and elimination of anesthetic residues are reviewed.Several prospects and suggestions are also provided for the future application and administration of fish anesthetics in China.

  8. Safety, efficacy, and patient acceptability of lidocaine hydrochloride ophthalmic gel as a topical ocular anesthetic for use in ophthalmic procedures

    Directory of Open Access Journals (Sweden)

    Michael A Page

    2009-10-01

    Full Text Available Michael A Page, Frederick W FraunfelderDepartment of Ophthalmology (Casey Eye Institute, Oregon Health and Science University, Portland, OR, USAPurpose: To review the current literature on safety, efficacy, and measures of surgeon and patient satisfaction with lidocaine hydrochloride gel as a tool for ocular anesthesia.Methods: Pubmed search using keywords “lidocaine gel,” “ophthalmic,” and “surgery” and compiling cross-references. Twenty-six total references were reviewed, including 15 prospective randomized controlled trials (RCTs, total N = 933, average N = 62, 6 nonrandomized prospective studies (total N = 234, average N = 39, 2 animal studies, 1 microbiologic study, and 2 letters to the editor.Results: The RCTs and nonrandomized prospective studies evaluated a number of measures including timing of onset of anesthesia, duration of anesthesia, intraoperative and postoperative pain, need for additional anesthetic applications, intracameral lidocaine levels, and adverse effects. Control groups received topical drops, subconjunctival anesthetic, retrobulbar anesthetic, or sham gel. Lidocaine gel was shown to be at least as effective for pain control as alternative therapies in all studies, with longer duration of action than topical drops. Patient and surgeon satisfaction were high, and adverse effects were rare and comparable to those for anesthetic drop formulations. Surgical settings included cataract, pterygium, trabeculectomy, strabismus, intravitreal injection, vitrectomy, and penetrating keratoplasty.Conclusions: Lidocaine gel is a safe, effective, and potentially underutilized tool for ophthalmic surgery.Keywords: lidocaine, gel, topical, ophthalmic, ocular, anesthetic

  9. The forced walking test: a novel test for pinpointing the anesthetic-induced transition in consciousness in mouse.

    Science.gov (United States)

    Hwang, Eunjin; Kim, Seunghwan; Shin, Hee-Sup; Choi, Jee Hyun

    2010-04-30

    In consciousness or anesthesia studies, pinpointing the precise moment of consciousness or anesthetic transition has been challenging because of the variable lag time between a treatment and its induced response. Here, we describe a novel behavioral method, a forced walking test, which pinpoints the moment of the anesthetic-induced loss of motion (LOM) without handling the animals manually. The mouse is forced to walk on a treadmill, and an anesthetic drug is administered into the peritoneum via a previously secured injection route. The physical activity and the angle of head posture are tracked using a motion sensor preinstalled on the animal's head. The moments of LOM and recovery of motion (ROM) are identified from the physical activity parameters obtained by the sensor. Comparison of our method with the conventional loss-of-righting-reflex assay showed that the time point of LOM was not significantly different between the two methods when examined with two different types of anesthetic agents, propofol and ketamine/xylazine cocktail. In addition, the electrophysiological signals simultaneously acquired in the cortex and the thalamus of the mouse during the forced walking test showed that the brain rhythms induced by ketamine/xylazine anesthesia were generated and terminated in a time-locked manner with respect to LOM and ROM, respectively. In conclusion, the forced walking test allows an objective and precise detection of anesthetic-induced LOM, as well as ROM during awakening from anesthesia, in test animals.

  10. Volatility of an Indian stock market A random matrix approach

    CERN Document Server

    Kulkarni, V

    2005-01-01

    We examine volatility of an Indian stock market in terms of aspects like participation, synchronization of stocks and quantification of volatility using the random matrix approach. Volatility pattern of the market is found using the BSE index for the three-year period 2000-2002. Random matrix analysis is carried out using daily returns of 70 stocks for several time windows of 85 days in 2001 to (i) do a brief comparative analysis with statistics of eigenvalues and eigenvectors of the matrix C of correlations between price fluctuations, in time regimes of different volatilities. While a bulk of eigenvalues falls within RMT bounds in all the time periods, we see that the largest (deviating) eigenvalue correlates well with the volatility of the index, the corresponding eigenvector clearly shows a shift in the distribution of its components from volatile to less volatile periods and verifies the qualitative association between participation and volatility (ii) observe that the Inverse participation ratio for the ...

  11. Forecasting Exchange Rate Volatility in the Presence of Jumps

    DEFF Research Database (Denmark)

    Busch, Thomas; Christensen, Bent Jesper; Nielsen, Morten Ørregaard

    of exchange rate futures options, allowingcalculation of option implied volatility. We find that implied volatility is an informationallyefficient but biased forecast of future realized exchange rate volatility. Furthermore,we show that log-normality is an even better distributional approximation...... for impliedvolatility than for realized volatility in this market. Finally, we show that the jump componentof future realized exchange rate volatility is to some extent predictable, and thatoption implied volatility is the dominant forecast of the future jump component.......We study measures of foreign exchange rate volatility based on high-frequency (5-minute) $/DM exchange rate returns using recent nonparametric statistical techniquesto compute realized return volatility and its separate continuous sample path and jumpcomponents, and measures based on prices...

  12. Bayesian Vector Autoregressions with Stochastic Volatility

    NARCIS (Netherlands)

    Uhlig, H.F.H.V.S.

    1996-01-01

    This paper proposes a Bayesian approach to a vector autoregression with stochastic volatility, where the multiplicative evolution of the precision matrix is driven by a multivariate beta variate.Exact updating formulas are given to the nonlinear filtering of the precision matrix.Estimation of the au

  13. Volatile components from Anthriscus sylvestris (L.) Hoffm

    NARCIS (Netherlands)

    Bos, R.; Koulman, A; Woerdenbag, H.J.; Quax, Wim; Pras, N.

    2002-01-01

    The volatile components of fresh leaves and roots from Anthriscus sylvestris (L.) Hoffm., obtained through hydrodistillation, were analysed by GC and GC-MS. This was compared to dichloromethane extracts of both fresh and dried leaf and root material. The monoterpene fraction (69-70%) dominated, whil

  14. Linux Incident Response Volatile Data Analysis Framework

    Science.gov (United States)

    McFadden, Matthew

    2013-01-01

    Cyber incident response is an emphasized subject area in cybersecurity in information technology with increased need for the protection of data. Due to ongoing threats, cybersecurity imposes many challenges and requires new investigative response techniques. In this study a Linux Incident Response Framework is designed for collecting volatile data…

  15. Explaining output volatility: The case of taxation

    DEFF Research Database (Denmark)

    Posch, Olaf

    the second moment of output growth rates without (long-run) effects on the first moment. Taking the model to the data, we exploit observed heterogeneity patterns to estimate effects of tax rates on macro volatility using panel estimation, explicitly modeling the unobserved variance process. We find a strong...

  16. Volume, Volatility and Public News Announcements

    DEFF Research Database (Denmark)

    Bollerslev, Tim; Li, Jia; Xue, Yuan

    We provide new empirical evidence for the way in which financial markets process information. Our results are based on high-frequency intraday data along with new econometric techniques for making inference on the relationship between trading intensity and spot volatility around public news...

  17. There's more to volatility than volume

    CERN Document Server

    Gillemot, L; Lillo, F; Gillemot, Laszlo; Lillo, Fabrizio

    2005-01-01

    It is widely believed that fluctuations in transaction volume, as reflected in the number of transactions and to a lesser extent their size, are the main cause of clustered volatility. Under this view bursts of rapid or slow price diffusion reflect bursts of frequent or less frequent trading, which cause both clustered volatility and heavy tails in price returns. We investigate this hypothesis using tick by tick data from the New York and London Stock Exchanges and show that only a small fraction of volatility fluctuations are explained in this manner. Clustered volatility is still very strong even if price changes are recorded on intervals in which the total transaction volume or number of transactions is held constant. In addition the distribution of price returns conditioned on volume or transaction frequency being held constant is similar to that in real time, making it clear that neither of these are the principal cause of heavy tails in price returns. We analyze recent results of Ane and Geman (2000) an...

  18. Volatile terpenoids from aeciospores of Cronartium fusiforme.

    Science.gov (United States)

    Laseter, J. L.; Weete, J. D.; Walkinshaw, C. H.

    1973-01-01

    Identification of the terpenoids present in the volatile fraction from aeciospores of the gall rust fungus Cronartium fusiforme. The major monoterpenoid hydrocarbons found to be present with only traces of camphene include alpha-pinene, beta-pinene, delta(3)-carene, myrcene, linonene, beta-phellandrene, and delta-terpinene. A number of monoterpenoid alcohols, acyclic sesquiterpenes, and aromatic compounds were also present.

  19. Permeation of volatile compounds through starch films

    NARCIS (Netherlands)

    Yilmaz, G.; Jongboom, R.O.J.; Feil, H.; Dijk, van C.; Hennink, W.E.

    2004-01-01

    The aim of this study was to gain insight into the factors that affect the permeation of volatiles through starch films. These films were obtained by casting gelatinized starch/water/glycerol mixtures. The films were dried and conditioned under different conditions (temperature and relative humidity

  20. Do Macroeconomic Announcements Cause Asymetric Volatility?

    NARCIS (Netherlands)

    P. de Goeij (Peter); W.A. Marquering (Wessel)

    2002-01-01

    textabstractIn this paper we study the impact of macroeconomic news announcements on the conditional volatility of stock and bond returns. Using daily returns on the S&P 500 index, the NASDAQ index, and the 1 and 10 year U.S. Treasury bonds, for January 1982 - August 2001, some interesting results e