Home About us Contact
|
Home About us Contact | ||
|
|
||
Rapid Emergence (rapid + emergence)
Selected AbstractsRapid emergence does not explain agitation following sevoflurane anaesthesia in infants and children: a comparison with propofolPEDIATRIC ANESTHESIA, Issue 1 2003Ira Todd Cohen MD Summary Background: Emergence agitation in children is frequently associated with the use of the new highly insoluble volatile anaesthetics. Rapid emergence has been cited as one of the possible causes. Propofol also permits rapid emergence from general anaesthesia but is not associated with agitation. Methods: The emergence characteristics of children receiving sevoflurane and propofol anaesthesia were examined. After induction with sevoflurane, 53 children, aged 2,36 months, who were undergoing ambulatory surgery, were randomized to receive maintenance anaesthesia with either sevoflurane or propofol. Introperative analgesia with either 2 µg·kg,1 of intravenous fentanyl or a caudal block with 0.25% bupivacaine was supplied according to surgical procedure. An observer blinded to anaesthetic technique recorded the time to achieve extubation and recovery and assessed emergence behaviour. Data were analysed using Wilcoxon scores, Kruskal,Wallis test, chi-square and multiple regression analysis. Results: The results showed that the time to extubation and recovery were similar between the two study groups, but that emergence agitation was significantly higher in the sevoflurane group compared with the propofol group. No relationship between analgesic technique and agitation scores was found. Conclusions: Although both sevoflurane and propofol allow for rapid emergence from general anaesthesia, only sevoflurane is associated with a high incidence of emergence agitation in infants and young children. Rapid emergence does not fully explain this phenomena. [source] Rapid emergence of hybrids between the two subspecies of Ophiostoma novo-ulmi with a high level of pathogenic fitnessPLANT PATHOLOGY, Issue 1 2010C. M. Brasier During the 1970s Europe was invaded by two subspecies of the Dutch elm disease pathogen Ophiostoma novo-ulmi: subsp. americana from the west and subsp. novo-ulmi from the east. As a result their geographic ranges began to overlap in several areas. Only a weak prezygotic barrier to hybridization exists between the subspecies and in 1980 two hybrids were detected in the Netherlands. A subset of 107 O. novo-ulmi isolates collected in a subspecies overlap zone in Limburg, Netherlands in 1983 was characterized for three phenotypic markers and seven RAPD PCR markers. By phenotype, 33% were shown to be hybrid whereas by RAPD markers 69% were shown to be hybrid. Some isolates shown to be hybrid by phenotype were not revealed to be hybrid by PCR and vice versa. Combining the phenotype and RAPD data the estimated hybrid frequency was ,78%. The mean growth rate of Limburg hybrid isolates was significantly faster than that of the Limburg subsp. novo-ulmi isolates but not significantly different from Limburg subsp. americana isolates. The Limburg hybrid isolates were just as pathogenic as the parent subspecies on both clonal Ulmus procera and on U. × Commelin. A subset of 100 isolates collected in another subspecies overlap zone at Orvieto, Italy in 1986 was also assessed with RAPD markers and ,72% were shown to be hybrids. When 20 isolates of a ,pure' subsp. novo-ulmi population in the Baltic Ports area of Poland collected in 1980 were assessed by RAPD markers three isolates exhibited early introgression of subsp. americana DNA. This study therefore demonstrates very rapid emergence of O. novo-ulmi subspecies hybrids and introgressants in Europe in the early 1980s. In terms of two major fitness characters, growth rate and pathogenicity, these early hybrids were as fit as their parent subspecies. It is likely that complex hybrid swarms are now expanding across the continent. [source] Rapid crystal growth without inherent supersaturation induced by nanoscale fluid flows?CRYSTAL RESEARCH AND TECHNOLOGY, Issue 1 2006M. J. Jones Abstract Crystal growth is a process that only takes place under non-equilibrium conditions and a necessary prerequisite is that the crystal is exposed to a phase that is supersaturated in the material the crystal is composed of, be it a solution, a vapour or a supercooled melt. In industrial mass crystallization the growth rate for a population of crystals (in suspension growth processes [1]) rarely exceeds mean linear velocities of 10 -7 ms -1. Here we present a mass crystallization process which is accompanied by rapid crystal growth several orders of magnitude faster and into a region of solution that is without inherent supersaturation. The material investigated is a solid hydrate that exhibits a solution mediated phase transition to its anhydrous form in the presence of methanol [2]. The phase transition is initiated simply by placing an amount of hydrate crystals into the solvent and is characterized by the rapid emergence of needle-shaped crystals. The needles emanate from the crystal faces of the hydrate crystals and grow into the solution, which is nominally free of the substance to be crystallized. The high growth rate of the crystals, which of the order of up to 10 -4 ms -1 is surprising. Although rapid needle growth has been observed before [3-9], to date a satisfactory explanation for needles growing under the abovementioned conditions is still outstanding. Based upon the topology of the crystals we propose a tentative mechanism for this phenomenon capable of explaining the unusually rapid growth and highlight those questions that need addressing in order to verify this mechanism. X-ray powder diffraction is used to characterize the crystal phase of the needles; confocal fluorescence microscopy reveals that the needles are hollow. The width of these needles is between 0.5 and 5 ,m, their length appears to be limited only by the amount of hydrate available for their formation. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Enhancement of the efficacy of erythromycin in multiple antibiotic-resistant gram-negative bacterial pathogensJOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2008S. Saha Abstract Aims:, To improve the efficacy of erythromycin, a hydrophobic antibiotic, against multiple antibiotic-resistant gram-negative bacterial pathogens by enhancing their outer membrane permeability. Methods and Results:, Fifty-one nonrepeat gram-negative bacterial pathogens of various genera, resistant to multiple antibiotics, including erythromycin, were selected by disc agar diffusion tests. The amphiphilic cationic steroid antibiotic, Ceragenin CSA-13, a potent permeabilizer of bacterial outer membranes, reduced the minimum inhibitory concentration of erythromycin in 92% of the bacterial pathogens selected for the test, when supplemented with erythromycin. A synergistic effect of Ceragenin CSA-13 and erythromycin in combination was also observed. Spectrofluorimetric study confirmed that Ceragenin CSA-13 acts by depolarizing the bacterial outer membrane. The toxicity of Ceragenin CSA-13 was evaluated to be insignificant by measuring ,median lethal dose' (LD50) on mouse model. Conclusions:, Ceragenin CSA-13 may be useful as an agent to make erythromycin effective against infections caused by multiple antibiotic resistant gram-negative bacteria. Significance and Impact of the Study:, The outcome of the study suggests erythromycin,Ceragenin combination as a new approach to overcome the problem associated with the rapid emergence of multi-drug-resistant pathogens. The insignificant toxicity of Ceragenin CSA-13, as found, supports the possibility of the application of this compound for human therapeutics. [source] Suppression of hepatitis C virus replication by protein kinase C-related kinase 2 inhibitors that block phosphorylation of viral RNA polymeraseJOURNAL OF VIRAL HEPATITIS, Issue 10 2009S.-J. Kim Summary., Hepatitis C virus (HCV) infection is a serious threat to human health worldwide. In spite of the continued search for specific and effective anti-HCV therapies, the rapid emergence of drug-resistance variants has been hampering the development of anti-HCV drugs designed to target viral enzymes. Targeting host factors has therefore emerged as an alternative strategy offering the potential to circumvent the ever-present complication of drug resistance. We previously identified protein kinase C-related kinase 2 (PRK2) as a cellular kinase that phosphorylates the HCV RNA-dependent RNA polymerase (RdRp). Here, we report the anti-HCV activity of HA1077, also known as fasudil, and Y27632, which blocks HCV RdRp phosphorylation by suppressing PRK2 activation. Treatment of a Huh7 cell line, stably expressing a genotype 1b HCV subgenomic replicon RNA, with 20 ,m each of HA1077 and Y27632 reduced the HCV RNA level by 55% and 30%, respectively. A combination of the inhibitors with 100 IU/mL interferon , (IFN-,) significantly potentiated the anti-HCV drug activities resulting in approximately a 2-log10 viral RNA reduction. We also found that IFN-, does not activate PRK2 as well as its upstream kinase PDK1 in HCV-replicating cells. Furthermore, treatment of HCV-infected cells with 20 ,m each of HA1077 and Y27632 reduced the levels of intracellular viral RNA by 70% and 92%, respectively. Taken together, the results identify PRK2 inhibitors as potential antiviral drugs that act by suppressing HCV replication via inhibition of viral RNA polymerase phosphorylation. [source] Labyrinthula terrestris: a new pathogen of cool-season turfgrassesMOLECULAR PLANT PATHOLOGY, Issue 6 2007MARY W. OLSEN ABSTRACT A new disease of turfgrass known as rapid blight is caused by Labyrinthula terrestris, a newly described member of the Labyrinthulids. This unusual group of microorganisms previously has been found in marine systems, and L. terrestris is the only member of the genus Labyrinthula known to be a pathogen of terrestrial plants. Members of this genus are defined by the formation of ectoplasmic networks in which the unicellular somatic cells move or ,glide'. Infections of cool-season turfgrasses occur most commonly when they are irrigated with suboptimal irrigation water with elevated salinity. Disease has been observed in 11 states in the United States and in the United Kingdom. A phylogenetic study indicates that isolates from turfgrass in the United States fall firmly within a clade containing other Labyrinthula spp. and that they came from a common lineage. Its rapid emergence as a turfgrass pathogen may coincide with increased use of relatively high-salinity water or reclaimed water for irrigation. L. terrestris is a potential problem in susceptible turfgrass varieties wherever soil salinity is allowed to accumulate as a result of poor soil structure or suboptimal quality irrigation water is used for irrigation. [source] Rapid emergence does not explain agitation following sevoflurane anaesthesia in infants and children: a comparison with propofolPEDIATRIC ANESTHESIA, Issue 1 2003Ira Todd Cohen MD Summary Background: Emergence agitation in children is frequently associated with the use of the new highly insoluble volatile anaesthetics. Rapid emergence has been cited as one of the possible causes. Propofol also permits rapid emergence from general anaesthesia but is not associated with agitation. Methods: The emergence characteristics of children receiving sevoflurane and propofol anaesthesia were examined. After induction with sevoflurane, 53 children, aged 2,36 months, who were undergoing ambulatory surgery, were randomized to receive maintenance anaesthesia with either sevoflurane or propofol. Introperative analgesia with either 2 µg·kg,1 of intravenous fentanyl or a caudal block with 0.25% bupivacaine was supplied according to surgical procedure. An observer blinded to anaesthetic technique recorded the time to achieve extubation and recovery and assessed emergence behaviour. Data were analysed using Wilcoxon scores, Kruskal,Wallis test, chi-square and multiple regression analysis. Results: The results showed that the time to extubation and recovery were similar between the two study groups, but that emergence agitation was significantly higher in the sevoflurane group compared with the propofol group. No relationship between analgesic technique and agitation scores was found. Conclusions: Although both sevoflurane and propofol allow for rapid emergence from general anaesthesia, only sevoflurane is associated with a high incidence of emergence agitation in infants and young children. Rapid emergence does not fully explain this phenomena. [source] Rapid emergence of hybrids between the two subspecies of Ophiostoma novo-ulmi with a high level of pathogenic fitnessPLANT PATHOLOGY, Issue 1 2010C. M. Brasier During the 1970s Europe was invaded by two subspecies of the Dutch elm disease pathogen Ophiostoma novo-ulmi: subsp. americana from the west and subsp. novo-ulmi from the east. As a result their geographic ranges began to overlap in several areas. Only a weak prezygotic barrier to hybridization exists between the subspecies and in 1980 two hybrids were detected in the Netherlands. A subset of 107 O. novo-ulmi isolates collected in a subspecies overlap zone in Limburg, Netherlands in 1983 was characterized for three phenotypic markers and seven RAPD PCR markers. By phenotype, 33% were shown to be hybrid whereas by RAPD markers 69% were shown to be hybrid. Some isolates shown to be hybrid by phenotype were not revealed to be hybrid by PCR and vice versa. Combining the phenotype and RAPD data the estimated hybrid frequency was ,78%. The mean growth rate of Limburg hybrid isolates was significantly faster than that of the Limburg subsp. novo-ulmi isolates but not significantly different from Limburg subsp. americana isolates. The Limburg hybrid isolates were just as pathogenic as the parent subspecies on both clonal Ulmus procera and on U. × Commelin. A subset of 100 isolates collected in another subspecies overlap zone at Orvieto, Italy in 1986 was also assessed with RAPD markers and ,72% were shown to be hybrids. When 20 isolates of a ,pure' subsp. novo-ulmi population in the Baltic Ports area of Poland collected in 1980 were assessed by RAPD markers three isolates exhibited early introgression of subsp. americana DNA. This study therefore demonstrates very rapid emergence of O. novo-ulmi subspecies hybrids and introgressants in Europe in the early 1980s. In terms of two major fitness characters, growth rate and pathogenicity, these early hybrids were as fit as their parent subspecies. It is likely that complex hybrid swarms are now expanding across the continent. [source] Effects of Donor Age and Cell Senescence on Kidney Allograft SurvivalAMERICAN JOURNAL OF TRANSPLANTATION, Issue 1 2009A. Melk The biological processes responsible for somatic cell senescence contribute to organ aging and progression of chronic diseases, and this may contribute to kidney transplant outcomes. We examined the effect of pre-existing donor aging on the performance of kidney transplants, comparing mouse kidney isografts and allografts from old versus young donors. Before transplantation, old kidneys were histologically normal, but displayed an increased expression of senescence marker p16INK4a. Old allografts at day 7 showed a more rapid emergence of epithelial changes and a further increase in the expression of p16INK4a. Similar but much milder changes occurred in old isografts. These changes were absent in young allografts at day 7, but emerged by day 21. The expression of p16INK4a remained low in young kidney allografts at day 7, but increased with severe rejection at day 21. Isografts from young donors showed no epithelial changes and no increase in p16INK4a. The measurements of the alloimmune response,infiltrate, cytology, expression of perforin, granzyme B, IFN-, and MHC,were not increased in old allografts. Thus, old donor kidneys display abnormal parenchymal susceptibility to transplant stresses and enhanced induction of senescence marker p16INK4a, but were not more immunogenic. These data are compatible with a key role of somatic cell senescence mechanisms in kidney transplant outcomes by contributing to donor aging, being accelerated by transplant stresses, and imposing limits on the capacity of the tissue to proliferate. [source] The use of propofol and remifentanil for the anaesthetic management of a super-obese patientANAESTHESIA, Issue 8 2007L. La Colla Summary Morbid obesity is defined as body mass index (BMI) >,35 kg.m,2, and super-obesity as BMI >,55 kg.m,2. We report the case of a 290-kg super-obese patient scheduled for open bariatric surgery. A propofol-remifentanil TCI (target controlled infusion) was chosen as the anaesthetic technique both for sedation during awake fibreoptic nasotracheal intubation and for maintenance of anaesthesia during surgery. Servin's weight correction formula was used for propofol. Arterial blood samples were taken at fixed time points to assess the predictive performance of the TCI system. A significant difference between measured and predicted plasma propofol concentrations was found. After performing a computer simulation, we found that predictive performance would have improved significantly if we had used an unadjusted pharmacokinetic set. However, in conclusion (despite the differences between measured and predicted plasma propofol concentrations), the use of a propofol-remifentanil TCI technique both for sedation during awake fibreoptic intubation and for Bispectral Index-guided propofol-remifentanil anaesthesia resulted in a rapid and effective induction, and operative stability and a rapid emergence, allowing rapid extubation in the operating room and an uneventful recovery. [source] | |||||||||||||