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Elimination
Kinds of Elimination Terms modified by Elimination Selected AbstractsTheoretical and kinetic study of the H + C2H5CN reactionJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 6 2010Jingyu Sun Abstract The reaction of H radical with C2H5CN has been studied using various quantum chemistry methods. The geometries were optimized at the B3LYP/6-311+G(d,p) and B3LYP/6-311++G(2d,2p) levels. The single-point energies were calculated using G3 and BMC-CCSD methods based on B3LYP/6-311++G(2d,2p) geometries. Four mechanisms were investigated, namely, hydrogen abstraction, C-addition/elimination, N-addition/elimination and substitution. The kinetics of this reaction were studied using the transition state theory and multichannel Rice-Ramsperger-Kassel-Marcus methodologies over a wide temperature range of 200,3000 K. The calculated results indicate that C-addition/elimination channel is the most feasible over the whole temperature range. The deactivation of initial adduct C2H5CHN is dominant at lower temperature with bath gas H2 of 760 Torr; whereas C2H5+HCN is the dominant product at higher temperature. Our calculated rate constants are in good agreement with the available experimental data. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010 [source] COMPUTER-CONTROLLED MICROWAVE HEATING TO IN-PACKAGE PASTEURIZE BEEF FRANKFURTERS FOR ELIMINATION OF LISTERIA MONOCYTOGENES,JOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2005LIHAN HUANG ABSTRACT The objective of this study was to develop an in-package pasteurization technology to kill Listeria monocytogenes in ready-to-eat meats using microwave heating. This technology utilized an infrared sensor to monitor the surface temperature of beef frankfurters during microwave heating. The aim was to increase the surface temperature of frankfurters to a set point lethal to L. monocytogenes. A feedback control mechanism was used to control the power to the microwave oven. Results indicated that the simple on-off control mechanism was able to maintain the surface temperature of beef frankfurters near the respective set points of 75, 80 or 85C used in this study. This pasteurization process was able to achieve a 7-log reduction of L. monocytogenes in inoculated beef frankfurters using a 600-W nominally rated microwave oven within 12,15 min. If optimized, this system may provide the food industry with a terminal, postlethality pasteurization technology to kill L. monocytogenes in ready-to-eat meats within the final packages. [source] PAIN REDUCTION WITH OPIOID ELIMINATIONPAIN MEDICINE, Issue 2 2002Article first published online: 4 JUL 200 Edward Covington, MD, Cleveland Clinic Foundation; Margaret Kotz, DO, Cleveland Clinic Foundation The last decade has seen a reversal of the historical belief that chronic opioid therapy (COT) was inadvisable in nonmalignant palm. Numerous studies demonstrate sustained pain reduction with chronic opioid therapy; however, there are clinical reports and animal models that suggest chronic opioids may at times exacerbate pain. Clearly, many patients without apparent structural deficit have persistent pain and dysfunction despite high dose opioid therapy. Thus, while opioids have been shown to be safe in long term use, the question of efficacy remains. Predictors of success in COT are not fully established. Studies of intrathecal opioids suggest that high levels of patient satisfaction and retrospective reports of benefit may occur despite minimal change in pain level and function. This raises the question of whether at times the purported benefits of long-term opioid therapy may be illusory. Consecutive admissions to a chronic pain rehabilitation program (n = 228) were studied. This program represents a biased population in that many referrals have dysfunction that is discordant with pathology, inordinate suffering and dysphoria, poorly explained pain, or substance use problems. Of 228, 56 were taking , 100 mg p.o. morphine equivalents/d on admission (mean 456 mg/d). Data are available on 46 of these receiving ,high dose' opioids. Patients participated in a rehabilitation program that included reconditioning, cognitive behavioral psychotherapy, adjuvant medications, and elimination of opioids and benzodiazepines. 43 (93%) experienced a reduction in pain with opioid elimination (from 7.2 to 4.0/10). Three experienced an increase in pain. Depression and functional impairment also improved. Cases will be presented of patients who believed they were benefiting from chronic opioid therapy, but improved after opioid elimination. They commonly described "getting myself back" after elimination of opioids. Physiological considerations and treatment implications will be described. [source] BORDER BARRIERS IN AGRICULTURAL TRADE AND THE IMPACT OF THEIR ELIMINATION: EVIDENCE FROM EAST ASIATHE DEVELOPING ECONOMIES, Issue 2 2010Kuo-I CHANG F13; F14; Q17 We investigate the impact of the elimination of import tariffs and nontariff policy barriers (NTPBs) on agricultural trade in a notional East Asian Free Trade Agreement using a Global Trade Analysis Project (GTAP)-based computable general equilibrium model. The investigation is divided into two parts. We first measure the NTPBs by employing a widely used method derived from the literature on border effects. Then, by adding into the GTAP database our estimates on the NTPBs, which the original GTAP database by its nature does incorporate, we compute the impact of the entire elimination of policy barriers (the complete reduction of import tariffs and NTPBs) on GDP. The result shows that there are remarkable differences between the effect of abolition of import tariffs and that of entire elimination of all import barriers. [source] Object combining: a new aggressive optimization for object intensive programsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 5-6 2005Ronald Veldema Abstract Object combining tries to put objects together that have roughly the same life times in order to reduce strain on the memory manager and to reduce the number of pointer indirections during a program's execution. Object combining works by appending the fields of one object to another, allowing allocation and freeing of multiple objects with a single heap (de)allocation. Unlike object inlining, which will only optimize objects where one has a (unique) pointer to another, our optimization also works if there is no such relation. Object inlining also directly replaces the pointer by the inlined object's fields. Object combining leaves the pointer in place to allow more combining. Elimination of the pointer accesses is implemented in a separate compiler optimization pass. Unlike previous object inlining systems, reference field overwrites are allowed and handled, resulting in much more aggressive optimization. Our object combining heuristics also allow unrelated objects to be combined, for example, those allocated inside a loop; recursive data structures (linked lists, trees) can be allocated several at a time and objects that are always used together can be combined. As Java explicitly permits code to be loaded at runtime and allows the new code to contribute to a running computation, we do not require a closed-world assumption to enable these optimizations (but it will increase performance). The main focus of object combining in this paper is on reducing object (de)allocation overhead, by reducing both garbage collection work and the number of object allocations. Reduction of memory management overhead causes execution time to be reduced by up to 35%. Indirection removal further reduces execution time by up to 6%. Copyright © 2005 John Wiley & Sons, Ltd. [source] Patients Spend More Time With the Physician for Excision of a Malignant Skin Lesion Than for Excision of a Benign Skin LesionDERMATOLOGIC SURGERY, Issue 3 2004Steven R. Feldman MD Background. Currently, there is a difference in reimbursement between excision of malignant and benign lesions. There is concern that there is not sufficient rationale for differential reimbursement for these two procedures. Objective. To assess whether there is a difference in physician work involved with excision of benign versus malignant skin tumors. Method. We searched National Ambulatory Medical Care Survey data for visits at which excision of benign and malignant skin lesions was performed. We compared the time spent with the physician at these two types of visits. To exclude confounding issues unrelated to the excision that would affect the time of visit, we excluded visits at which multiple diagnoses were addressed. Results. The mean time spent with the physician at visits for excision of benign lesions was 22.9±1.0 minutes. The mean time spent with the physician at visits for excision of malignant lesions was 30.0±1.7, 30% longer (p < 0.001). The longer time for excision of malignant lesions remained significant after controlling for age, gender, and race. Conclusion. Excision of malignant lesions involves more physician work than does excision of benign lesions. Elimination of differential compensation for benign versus malignant skin lesion procedures would not enhance the accuracy of reimbursement. In the absence of any compelling rationale to change the existing differential reimbursement, the proposals to do so are not warranted. [source] Developmental cell death during Xenopus metamorphosis involves BID cleavage and caspase 2 and 8 activationDEVELOPMENTAL DYNAMICS, Issue 8 2006D. Du Pasquier Abstract Elimination of tadpole organs during Xenopus metamorphosis is largely achieved through apoptosis, and recent evidence suggest involvement of the mitochondrial death route and bax-initiated caspase-3 and -9 deployment. However, events upstream of the activation of Bax are unknown. In other models, proteins of the BH3-only group such as BID are known to assure this function. We show that Xenopus bid transcript levels increase at metamorphosis in larval cells destined to disappear. This increase correlates with an abrupt rise in Caspase-2 and -8 mRNA levels and an enhanced activity of Caspase-2 and -8. In BIDGFP transgenic animal's tail regression is accelerated. The cleavage of BIDGFP fusion protein during natural or T3 -induced metamorphosis was specifically inhibited by caspase-8 inhibitors. Our results show that tail regression at metamorphosis implicates an apoptotic pathway inducible by T3 hormone in an organ autonomous manner and involving the cell death executioners BID and Caspases-2 and -8. Developmental Dynamics 235:2083,2094, 2006. © 2006 Wiley-Liss, Inc. [source] A methodology for inferring the causes of observed impairments in aquatic ecosystems,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2002Glenn W. Suter II Abstract Biological surveys have become a common technique for determining whether aquatic communities have been injured. However, their results are not useful for identifying management options until the causes of apparent injuries have been identified. Techniques for determining causation have been largely informal and ad hoc. This paper presents a logical system for causal inference. It begins by analyzing the available information to generate causal evidence; available information may include spatial or temporal associations of potential cause and effect, field or laboratory experimental results, and diagnostic evidence from the affected organisms. It then uses a series of three alternative methods to infer the cause: Elimination of causes, diagnostic protocols, and analysis of the strength of evidence. If the cause cannot be identified with sufficient confidence, the reality of the effects is examined, and if the effects are determined to be real, more information is obtained to reiterate the process. [source] Reduced plasticity of cortical whisker representation in adult tenascin-C-deficient mice after vibrissectomyEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2004Anita Cybulska-Klosowicz Abstract The effect of the extracellular matrix recognition molecule tenascin-C on cerebral plasticity induced by vibrissectomy was investigated with 2-deoxyglucose (2DG) brain mapping in tenascin-C-deficient mice. Unilateral vibrissectomy sparing row C of vibrissae was performed in young adult mice. Two months later, cortical representations of spared row C vibrissae and control row C on the other side of the snout were visualized by [14C]2DG autoradiography. In both wild-type and tenascin-C-deficient mice, cortical representation of the spared row was expanded in all layers of the barrel cortex. However, the effect was significantly more extensive in wild-type animals than in the mutant. Elimination of tenascin-C by genetic manipulation thus reduces the effect of vibrissectomy observed in the somatosensory cortex. No increase in number of fibres in the vibrissal nerve of spared vibrissae was seen, and occurrence of additional nerve to the spared follicle was very rare. Thus, in tenascin-C-deficient mice functional plasticity seems to be impaired within the CNS. [source] Cyclization of Trichloroacetimidates by Olefin Aminopalladation ,-Heteroatom EliminationEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 36 2009Ansis Maleckis Abstract The cyclization of ,-acetoxy- O -allyl- and ,-acetoxy- O -homoallyl-trichloroacetimidates to 4-vinyloxazolines and a 4-vinyldihydrooxazine has been efficiently achieved by olefin aminopalladation,,-heteroatom elimination. (Z)-Allylic imidates bearing a secondary ,-acetoxy group underwent PdII -catalysed cyclization to give the E isomers of 4-vinyloxazolines selectively and gave no Overman rearrangement products. Using a chiral substrate, it has been demonstrated that cyclization to 4-vinyloxazolines occurs with high chirality transfer. Stereoselective E isomer formation and chirality transfer provided a basis from which to discuss the possible reaction mechanism. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] A Versatile Synthesis of 5,-Functionalized Nucleosides Through Regioselective Enzymatic Hydrolysis of Their Peracetylated PrecursorsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 12 2009Teodora Bavaro Abstract We describe a chemo-enzymatic synthesis of modified nucleosides through lipase-catalyzed hydrolysis of their peracetylated precursors. It was found from screening of a large number of substrates that these enzymes' regioselectivities were affected by the sugar and the nucleobase structures. By selecting the best enzyme for each substrate in terms of activity and regioselectivity, we prepared a small library of differently monodeprotected purine and pyrimidine nucleosides useful as intermediates for the synthesis of high-value nucleosides and mononucleotides. By this approach, the chemo-enzymatic preparation of doxifluridine (14) anduridine 5,-monophosphate (5,-UMP, 15) from peracetylated uridine 1 was carried out. Elimination of many of the processing stages associated with existing methods was achieved, and higher yields and products of increased purity were generated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Regiospecific Synthesis of 4-Deoxy- D - threo -hex-3-enopyranosides by Simultaneous Activation,Elimination of the Talopyranoside Axial 4-OH with the NaH/Im2SO2 System: Manifestation of the Stereoelectronic EffectEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 23 2006Emanuele Attolino Abstract A new and high-yielding method for the regioselective preparation of 4-deoxy- and 2,4-dideoxy-2-acetamido-,- D - threo -hex-3-enopyranosides has been developed. The process involves a simultaneous activation,elimination of the OH-4 group of ,- D -talopyranosides and 2-acetamido-2-deoxy-,- D -talopyranosides, mediated by the NaH/N,N,-sulfuryldiimidazole system at ,30 °C. The same reaction applied on the analogous ,- D -galactopyranosides takes place without any regioselectivity, affording mixtures of hex-3- and hex-4-enopyranosides. In the case of the methyl 2,3,6-tri- O -benzyl-,- D -talo- and ,- D -galactopyranosides, the corresponding 4- O -imidazylates can be isolated by quenching the reactions at ,30 °C. Upon warming these crude products to room temperature, the ,- talo -4- O -imidazylate gives the corresponding hex-3-eno derivative in very high yield, but its ,- galacto analogue gives the hex-4-enopyranoside enol ether in poor yield. The different regiochemical outcome between the talo and the galacto series has been attributed to the stereoelectronic effect exerted, exclusively in talo -configured compounds, by the axially disposed C-2 electronegative substituent, which selectively accelerates the breaking of the antiperiplanar C(3),H bond. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] How Did the Elimination of the US Earnings Test above the Normal Retirement Age Affect Labour Supply Expectations?,FISCAL STUDIES, Issue 2 2008Pierre-Carl Michaud H55; J22 Abstract We look at the effect of the 2000 repeal of the earnings test above the normal retirement age (NRA) on the self-reported probabilities of working full-time after ages 65 and 62 of male workers in the US Health and Retirement Study (HRS). Using administrative records on social security benefit entitlements linked to the HRS survey data, we can distinguish groups of respondents according to the predicted effect of the earnings test before its repeal on their marginal wage rate after the NRA. We use panel data models with fixed and random effects to investigate the effect of the repeal. We find that male workers whose predicted marginal wage rate increased because the earnings test was repealed had the largest increase in the subjective probability of working full-time after age 65. We find no significant effects of the repeal on the subjective probability of working full-time past age 62. [source] Abnormal social behaviors in mice lacking Fgf17GENES, BRAIN AND BEHAVIOR, Issue 3 2008K. Scearce-Levie The fibroblast growth factor family of secreted signaling molecules is essential for patterning in the central nervous system. Fibroblast growth factor 17 (Fgf17) has been shown to contribute to regionalization of the rodent frontal cortex. To determine how Fgf17 signaling modulates behavior, both during development and in adulthood, we studied mice lacking one or two copies of the Fgf17 gene. Fgf17-deficient mice showed no abnormalities in overall physical growth, activity level, exploration, anxiety-like behaviors, motor co-ordination, motor learning, acoustic startle, prepulse inhibition, feeding, fear conditioning, aggression and olfactory exploration. However, they displayed striking deficits in several behaviors involving specific social interactions. Fgf17-deficient pups vocalized less than wild-type controls when separated from their mother and siblings. Elimination of Fgf17 also decreased the interaction of adult males with a novel ovariectomized female in a social recognition test and reduced the amount of time opposite-sex pairs spent engaged in prolonged, affiliative interactions during exploration of a novel environment. After social exploration of a novel environment, Fgf17-deficient mice showed less activation of the immediate-early gene Fos in the frontal cortex than wild-type controls. Our findings show that Fgf17 is required for several complex social behaviors and suggest that disturbances in Fgf17 signaling may contribute to neuropsychiatric diseases that affect such behaviors. [source] Endodontic considerations in the elderlyGERODONTOLOGY, Issue 4 2004P. Finbarr Allen Tooth retention has increased significantly in older adults, and dentists are now challenged by the need to preserve critical teeth. There will be a need to consider endodontic therapy, and this paper describes how successful endodontics can be provided for elderly patients. Strategic treatment planning is essential, and preservation of key teeth will facilitate satisfactory oral function for elderly patients. These teeth may be important in achieving and maintaining an intact anterior dental arch, for removable partial denture retention or preservation of alveolar bone. In some cases, this can only be achieved if endodontic procedures are undertaken. When infection of a root canal is present, there is no reason why good quality endodontic therapy should not work in a healthy elderly patient. Elimination of infection can be challenging in narrow root canals, and a systematic approach for improving access into and negotiating these canals is outlined. [source] A Study of the Stereochemical Course of , -Oxygen Elimination with a Rhodium(I) ComplexHELVETICA CHIMICA ACTA, Issue 12 2002Masahiro Murakami The stereochemical course of , -oxygen elimination of an organorhodium(I) complex was investigated through the Rh-catalyzed addition of phenylboronic acid to a chiral propargyl acetate to produce an allene. The degree of chirality transfer suggests that the , -oxygen elimination takes place in both syn and anti modes. [source] When Parallel Paths Cross: Competition and the Elimination of Sex Segregation in the Education Fraternities, 1969-1974HISTORY OF EDUCATION QUARTERLY, Issue 2 2003Laurie Moses Hines First page of article [source] Use of paroxetine for the treatment of depression and anxiety disorders in the elderly: a reviewHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 3 2003*Article first published online: 11 DEC 200, Michel Bourin Abstract Paroxetine is a potent selective serotonin reuptake inhibitor (SSRI) with indications for the treatment of depression, obsessive, compulsive disorder, panic disorder and social phobia. It is also used in the treatment of generalized anxiety disorder, post-traumatic stress disorder, premenstrual dysphoric disorder and chronic headache. There is wide interindividual variation in the pharmacokinetics of paroxetine in adults as well as in the elderly with higher plasma concentrations and slower elimination noted in the latter. Elimination is also reduced in severe renal and hepatic impairment, however, serious adverse events are extremely rare even in overdose. A Pub Med search was used to collect information on the efficacy and tolerability in elderly patients. There are few studies of depression in the elderly and only one study in the old,old. In anxiety disorders including general anxiety disorder, panic disorder, obsessive,compulsive disorder and social anxiety, there are no studies at all in the elderly. However, the safety of the drug allows its prescription in the elderly. In summary, paroxetine is well tolerated in the treatment of depression in those between the ages of 65 and 75, although few studies have examined its use in those of 75 and older. Copyright © 2002 John Wiley & Sons, Ltd. [source] The International Covenant on Economic, Social and Cultural Rights as a tool for combating discrimination against women: general observations and a case study on Algeria*INTERNATIONAL SOCIAL SCIENCE JOURNAL, Issue 184 2005Karima Bennoune The International Covenant on Economic, Social and Cultural Rights (ICESCR) is vital to protecting the human rights of women. This is reflected in the substantive rights which the treaty guarantees and its procedural emphasis on non-discrimination. The ICESCR now has 151 State Parties, as compared with 180 states that have ratified the Convention on the Elimination of All Forms of Discrimination against Women (CEDAW). While the latter is a lightning rod for opposition to the advancement of women's rights, the former is not. It may, therefore, be a particularly useful tool for combating discrimination against women, especially in the Muslim world where resistance to CEDAW in conservative quarters is strong. Still, some argue that the Committee on Economic, Social and Cultural Rights, which monitors implementation of the ICESCR, needs to further elaborate its jurisprudence on women's issues. Against such a complex backdrop, this study will explore the utility of the ICESCR in combating discrimination against women, looking in particular at the example of Algeria, which became a State Party in 1989. [source] Phosphorylation by COP9 Signalosome-Associated CK2 Promotes Degradation of p27 during the G1 Cell Cycle PhaseISRAEL JOURNAL OF CHEMISTRY, Issue 2 2006Xiaohua Huang The cell cycle regulator p27Kip1 (p27) is controlled by 26S proteasome-mediated proteolysis by two different pathways. From the S till the G2 phase of the cell cycle, degradation of p27 takes place in the nucleus and is initiated by CDK2-dependent phosphorylation of threonine 187 with subsequent ubiquitination by the SCFSkp2 ubiquitin ligase. During the G1 cell cycle phase (G1), p27 breakdown is cytosolic and is initiated by nuclear export with subsequent ubiquitination by a RING finger ligase called kip1 ubiquitination complex. Here we show that the COP9 signalosome (CSN) is a regulator of p27 proteolysis during G1. The CSN interacts with p27 and the CSN-associated kinase CK2 phosphorylates p27 at two regions. One is central to the protein (amino acids 101,113), and the other was mapped near to the C-terminus (amino acids 170,189). Elimination of the putative C-terminal phosphorylation sites stabilizes ectopic p27 towards proteasomal degradation and abolishes CSN,p27 binding. Inhibition of CSN-associated kinase activity by curcumin attenuates loss of p27 upon cell cycle re-entry. Similar but not additive effects of the phosphoinositol-3-kinase blocker LY 290042 may point to a common pathway of CSN-associated CK2 and protein kinase B/Akt (Akt) in regulating p27 abundance. Akt is found in Flag pulldowns of lysates obtained from cells permanently expressing Flag-tagged CSN2, indicating that Akt is a novel kinase associated with the CSN. Thus, the CSN seems to regulate p27 proteolysis at G1 downstream of Ras-mediated signal pathways. [source] Performance Impact of the Elimination of Direct Labor Variance Reporting: A Field StudyJOURNAL OF ACCOUNTING RESEARCH, Issue 4 2002Rajiv D. Banker Using a field study approach, we examine two competing perspectives on direct labor variance reporting: some argue that direct labor variance reporting is costly and cumbersome, and should be eliminated; whereas others contend that without direct labor variance information, managers will not be able to monitor workers effectively, causing workers to shirk and worker productivity to decline. Specifically, we investigate the productivity and quality impacts of eliminating direct labor variance reporting with panel data containing 36 months of data from seven experimental plants that eliminated direct labor variance reporting and 11 control plants that did not. The experimental plants experienced a significant decline in labor productivity compared to the control plants. Also, the experimental plants showed an improvement in product quality, indicating that workers reallocate their efforts to other tasks as a result of the change in the information set available to evaluate them. [source] Elimination of minimal FFT grid-size limitationsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2002David A. Langs The fast Fourier transform (FFT) algorithm as normally formulated allows one to compute the Fourier transform of up to N complex structure factors, F(h), N/2 ,h > ,N/2, if the transform ,(r) is computed on an N -point grid. Most crystallographic FFT programs test the ranges of the Miller indices of the input data to ensure that the total number of grid divisions in the x, y and z directions of the cell is sufficiently large enough to perform the FFT. This note calls attention to a simple remedy whereby an FFT can be used to compute the transform on as coarse a grid as one desires without loss of precision. [source] Slowed Progression or Elimination of Atherosclerosis by Low-Frequency Electrical ImpulsesJOURNAL OF CARDIAC SURGERY, Issue 1 2003Ph.D., Valeri Chekanov M.D. In this investigation we demonstrated the slow progression or elimination of atherosclerosis by low-frequency EI in case of moderate atherosclerosis (after eight weeks of HCD). Methods: Series I rabbits (control group) were fed HCD for eight weeks. Series II rabbits were fed HCD for eight weeks and were then switched to normal diet for eight weeks (no EI). Series III rabbits were fed HCD for eight weeks and then switched to a normal diet with simultaneous EI (applied near the abdominal aorta) for eight weeks (3 V, 30 single impulses per minute, 24 hours/day). After euthanization, the level of atherosclerosis, percentage of surface area involved in the atherosclerosis process, and an atherosclerosis score were calculated in the aortic arch, thoracic and abdominal aorta. Results: Statistically significant differences were seen in the level of atherosclerosis in the abdominal aorta between series III animals (0.4 ± 0.2) and the other two groups: 1.5 ± 0.4 in series I (HCD only), 1.2 ± 0.3 in series II (HCD then normal diet). Gross examination of the surface also revealed statistically significant differences (p < 0.05) in the percentage of atherosclerosis between the control series I (30.1 ± 4.1%) and series II (21.3 ± 3.6%), compared with series III (5.5 ± 5.4%). In addition, the atherosclerosis score was also significantly different: 45.8 ± 3.9 in series I, 25.2 ± 6.9 in series II, and 2.2 ± 2.0 in series III (p < 0.05). Conclusion: Our study showed that, when applied near the abdominal aorta, low-frequency electrical impulses decrease atherosclerotic deposition in the abdominal aorta. (J Card Surg 2003; 18:47-58) [source] ATP-Induced Dormant Pulmonary Veins Originating from the Carina Region After Circumferential Pulmonary Vein Isolation of Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2010KOJI KUMAGAI M.D., Ph.D. Dormant Pulmonary Veins from the Carina Region.,Introduction: Elimination of transient pulmonary vein recurrences (dormant PVs) induced by an ATP injection and ablation at the PV carina region is an effective strategy for atrial fibrillation (AF) ablation. The relationship between dormant PVs and the PV carina region has not been evaluated. Methods: A total of 212 consecutive symptomatic AF patients underwent circumferential PV electrical isolation (CPVEI) with a double lasso technique. They were divided into 2 groups in a retrospective review; Group 1: those given an ATP injection during an intravenous isoproterenol infusion after the CPVEI (n = 106), and Group 2: those in which it was not given after the CPVEI (n = 106). Radiofrequency energy was applied at the earliest dormant PV activation site identified using a Lasso catheter on the CPVEI line and then PV carina region if it was ineffective. Results: After a successful PVEI, 54 patients (51%) in Group 1 had PV reconnections during an ATP injection. Acute PVEI sites were observed on the carina region within the CPVEI line in the right PVs (16%) and left PVs (10%). Dormant PVs were reisolated at the carina region in the right PVs (23%) and left PVs (26%). The distribution of the dormant PV sites, except for the RIPV, significantly differed from that of the acute PVEI sites (P < 0.05). Further, AF recurred significantly in the Group 2 patients as compared to those in Group 1 during 16 ± 6.1 months of follow-up (P < 0.05). Conclusion: PV carina region origins may partly be responsible for an acute PVEI and potential recurrences. (J Cardiovasc Electrophysiol, Vol. 21, pp. 494-500, May 2010) [source] Catheter Ablation of Chronic Atrial Fibrillation Targeting the Reinitiating TriggersJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 1 2000MICHEL HAÏSSAGUERRE M.D. Trigger Ablation in Chronic AF. Introduction: We assessed the mode of reinitiation of atrial fibrillation (AF) after cardioversion and the efficacy of ablating these foci of reinitiation in patients with chronic AF. Methods and Results: Fifteen patients, 7 with structural heart disease, underwent mapping and catheter ablation of drug-resistant AF documented to he persistent for 5 ± 4 months. In all patients, cardioversion was followed by documentation of P on T atrial ectopy and early recurrence, which allowed mapping of the reinitiating trigger or the source of ectopy. Radiofrequency (RF) ablation was performed at pulmonary vein (PV) ostia using a target temperature of 50°C and a power limit of 30 to 40 W, with the endpoint being interruption of all local muscle conduction. A total of 32 arrhythmogenic PVs and 2 atrial foci (left septum and left appendage) were identified: 1, 2, and 3 or 4 PVs in 5, 3, and 6 patients. RF applications at the ostial perimeter resulted in progressively increasing delay, followed by abolition of PV potentials in 8, but potentials persisted in 6. A single ablation session was performed in 7 patients and 8 underwent two or three sessions because of recurrence of AF; ablation was directed at the same source due to recovery of local PV potential or at a different PV. No PV stenosis was noted either acutely or at repeated follow-up angiograms. Nine patients (60%) were in stable sinus rhythm without antiarrhythmic drugs at follow-up of 11 ± 8 months. Anticoagulants were interrupted in 7 patients. Conclusion: PVs are the dominant triggers reinitiating chronic AF in this patient population. Elimination of PV potentials by ostial RF applications results in stable sinus rhythm in 60%. A larger group and longer follow-up are needed to investigate further the role of trigger ablation in curative therapy for chronic AF. [source] Influence of temperature on silver accumulation and depuration in rainbow troutJOURNAL OF FISH BIOLOGY, Issue 6 2004J. W. Nichols To assess the influence of water temperature on silver uptake, rainbow trout Oncorhynchus mykiss(c. 50 g; held at 13° C) were exposed to 0·1 ,M AgNO3 in ion-poor water for 1 week at 4 and 16° C without previous temperature acclimation. To assess the influence of temperature on elimination of previously accumulated Ag, rainbow trout were exposed to 0·1 ,M AgNO3 in ion-poor water for 1 week at 12° C, then were randomly divided amongst two Ag-free water containers, differing only in temperature (3 and 16° C), for 2 months. In the uptake study greater accumulation of Ag was seen in the gills, plasma and especially the livers and bile of ,warm' rainbow trout (16° C) compared to ,cold' rainbow trout (4° C), which can be explained by the higher metabolic rates of the warmer fish. In the depuration study there was no net elimination of Ag from the livers and bile but there was biphasic elimination of Ag from the gills and plasma of ,warm' and ,cold' fish, but with few differences between them. This indicated that temperature-dependent processes were less important in Ag elimination than in Ag uptake. Toxicokinetic modelling of Ag uptake by livers indicated four-fold greater uptake of Ag by ,warm' rainbow trout compared to ,cold' rainbow trout (one compartment uptake model). Elimination of previously accumulated Ag from the plasma was best fitted by a two compartment rate-constant based model, with approximately half the plasma Ag load eliminated within 24 h, followed by slower elimination of Ag over 2 months. [source] Acidified Sodium Chlorite as an Alternative to Chlorine for Elimination of Salmonella on Alfalfa SeedsJOURNAL OF FOOD SCIENCE, Issue 4 2009C.-H. Liao ABSTRACT:, The health and environmental hazard associated with the use of chlorine for food processing has been documented previously. This study was conducted to determine if acidified sodium chlorite (ASC) could be used to replace calcium hypochlorite (Ca[OCl]2) for disinfection of alfalfa seeds. Contaminated seeds containing approximately 1.5 × 107 CFU/g of Salmonella were treated with ASC or Ca(OCl)2 at different concentrations and for different periods of time. Results showed that the efficacy of ASC and Ca(OCl)2 for elimination of Salmonella on contaminated seeds could be improved greatly by extending the treatment time from the traditional 15 to 45 min. Treatment of seeds with 800 ppm of ASC for 45 min reduced the number of Salmonella by 3.9 log units, approximately 1.2 log units higher than that treated with 20000 ppm of Ca(OCl)2. Treatment of seeds with a lower concentration (100 to 400 ppm) of ASC for 45 min reduced the number of Salmonella by 1.3 to 2.2 log units. Soaking alfalfa seeds in 800 ppm of ASC for 45 min did not affect seed germination. However, soaking seeds in 20000 ppm of Ca(OCl)2 for 45 min reduced seed germination by 20%. Unlike Ca(OCl)2, antimicrobial efficiency of ASC was not affected by pre-exposure to alfalfa seeds. Data presented also showed that Salmonella on newly inoculated seeds that had been stored at 4 °C for less than 7 d were more sensitive to sanitizer treatment than those on seeds that had been stored for 4 wk or longer. [source] Effectiveness of Radiation Processing for Elimination of Salmonella Typhimurium from Minimally Processed Pineapple (Ananas comosus Merr.)JOURNAL OF FOOD SCIENCE, Issue 3 2007Ravindranath Shashidhar ABSTRACT:, The microbiological quality of market samples of minimally processed (MP) pineapple was examined. The effectiveness of radiation treatment in eliminating Salmonella Typhimurium from laboratory inoculated ready-to-eat pineapple slices was also studied. Microbiological quality of minimally processed pineapple samples from Mumbai market was poor; 8.8% of the samples were positive for Salmonella. D10 (the radiation dose required to reduce bacterial population by 90%) value for S. Typhimurium inoculated in pineapple was 0.242 kGy. Inoculated pack studies in minimally processed pineapple showed that the treatment with a 2-kGy dose of gamma radiation could eliminate 5 log CFU/g of S. Typhimurium. The pathogen was not detected from radiation-processed samples up to 12 d during storage at 4 and 10 °C. The processing of market samples with 1 and 2 kGy was effective in improving the microbiological quality of these products. [source] Normal nigrostriatal innervation but dopamine dysfunction in mice carrying hypomorphic tyrosine hydroxylase allelesJOURNAL OF NEUROSCIENCE RESEARCH, Issue 4 2003Susanna Althini Abstract We investigated the use of the mouse tyrosine hydroxylase (TH) gene to drive knock-in constructs in catecholaminergic neurons. Two targeting constructs representing truncated forms of either of the BMP receptors ALK-2 or BMPR-II preceded by an internal ribosome entry site (IRES) were introduced into the 3, untranslated region of TH. An frt-flanked neomycin-resistance (neor) cassette was placed in the 3, end of the targeting constructs. Mice homozygous for the knock-in alleles showed various degrees of hypokinetic behavior, depending mainly on whether the neor cassette was removed. In situ hybridization and immunohistochemistry showed that TH mRNA and protein were variously down-regulated in these mouse strains. Reduced levels of dopamine and noradrenalin were found in several brain areas. However, number and morphology of neurons in substantia nigra and their projections to striatum appeared normal in the neor -positive TH hypomorphic mice as examined by markers for L-aromatic amino acid decarboxylase and the dopamine transporter. Elimination of the neor cassette from the knock-in alleles partially restored TH and dopamine levels. The present neor -positive TH hypomorphic mice show that nigrostriatal innervation develops independently of TH and should find use as a model for conditions of reduced catecholamine synthesis, as seen in, for example, L-dihydroxyphenylalanine-responsive dystonia/infantile parkinsonism. © 2003 Wiley-Liss, Inc. [source] Elimination and exchange of trifluoroacetate counter-ion from cationic peptides: a critical evaluation of different approachesJOURNAL OF PEPTIDE SCIENCE, Issue 3 2008Stéphane Roux Abstract Most synthesized peptides are nowadays produced using solid-phase procedures. Due to cleavage and purification conditions, they are mainly obtained in the presence of trifluoroacetic acid (TFA) and, for cationic peptides, as trifluoroacetate (TF-acetate) salts. However, TF-acetate interferes with physicochemical characterizations using infrared spectroscopy and might significantly affect the in vivo studies. Thus, TF-acetate exchange by another counter-ion is often required. Up to now, the classical procedure has consisted of freeze-drying the peptide several times in the presence of an excess of a stronger acid than TFA (pKa ,0): generally HCl (pKa = , 7). This approach means that working at pH < 1 can induce peptide degradation. We therefore tested three different approaches to exchange the tightly bound TF-acetate counter-ion from the dicationic octapeptide lanreotide: (i) reverse-phase HPLC, (ii) ion-exchange resin, and (iii) deprotonation/reprotonation cycle of the amino groups. The first two approaches allow the partial to almost complete exchange of the TF-acetate counter-ion by another ion from an acid weaker than TFA, such as acetic acid (pKa = 4.5), and the third requires a basic solution that permits the complete removal of TF-acetate counter-ion. The efficiency of these three procedures was tested and compared by using different analytical techniques such as 19F-NMR, 1H-NMR and attenuated total reflectance Fourier transformed infrared spectroscopy (ATR FT-IR). We also show that ATR-IR can be used to monitor the TFA removal. The counter-ion exchange procedures described in this study are easy to carry out, fast, harmless and reproducible. Moreover, two of them offer the very interesting possibility of exchanging the initial TF-acetate by any other counter-ion. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||||||||||||||||||||