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Important Observation (important + observation)
Selected AbstractsChronic lung disease: oxygen dogma revisitedACTA PAEDIATRICA, Issue 2 2001O D Saugstad Since the discovery of retrolental fibroplasia, and the role of oxygen in its development, oxygen has been considered a double-edged sword in neonatal medicine, the utmost care being exercised in order not to give too much oxygen (1). However, the important observation that hypoxaemia might induce pulmonary vasoconstriction (2) and airway constriction (3) in infants at risk for bronchopulmonary dysplasia has resulted in only a minor upward adjustment of oxygen supplementation in many neonatal units. Since oxygen toxicity has long been linked not only to retinopathy of prematurity but also to bronchopulmonary dysplasia (4), it is relevant to ask whether an increased FiO2 might have any detrimental effects on babies. [source] Effect of Cathode and Anode Voltage on an Ion Sheath Thickness in a Magnetically Confined Diffusion PlasmaCONTRIBUTIONS TO PLASMA PHYSICS, Issue 10 2007M. Kr. Abstract This article reports about the ion sheath thickness variation occurring in front of a negatively biased plate immersed in the target plasma region of a double plasma device. The target plasma is produced due to the local ionization of neutral gas by the high energetic electrons coming from the source region (main discharge region). It is observed that for an increase in cathode voltage (filament bias voltage) in the source region, the ion flux into the plate increases. As a result, the sheath at the plate contracts. Again, for an increase in source anode voltage (magnetic cage bias), the ion flux to the plate decreases. As a result, the sheath expands at the plate. The ion sheath formed at the separation grid of the device is found to expand for an increase in cathode voltage and it contracts for an increase in the anode voltage of the main discharge region. One important observation is that the applied anode bias can control the Bohm speed of the ions towards the separation grid. Furthermore, it is observed that the ion current collected by the separation grid is independent of changes in plasma density in the diffusion region but is highly dependent on the source plasma parameters. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Detection of activity among uncultured Actinobacteria in a drinking water reservoirFEMS MICROBIOLOGY ECOLOGY, Issue 3 2006Jeppe L. Nielsen Abstract The abundance, identity and activity of uncultured Bacteria and Actinobacteria present in a drinking water reservoir (North Pine Dam, Brisbane, Australia) were determined using a combination of fluorescence in situ hybridization (FISH) alone or with catalysed reporter deposition (CARD-FISH) with microautoradiography. The CARD-FISH technique was modified relative to previous described procedures and performed directly on gelatine cover slips in order to allow simultaneous combination with microautoradiography. Almost twofold higher numbers of microorganisms could be identified as either Bacteria or Actinobacteria using the CARD-FISH technique as compared with the traditional FISH technique. A combination of FISH or CARD-FISH with microautoradiography showed generally higher activity among the Actinobacteria than among all Bacteria. Another important observation was that many cells within the FISH-negative populations of both Actinobacteria and Bacteria were actively assimilating thymidine. Thus, great care should be taken when extrapolating the active fraction of a prokaryotic community to be equivalent to the FISH-detectable population in such environments. Bacterial groups within Actinobacteria produce the odours geosmin and 2-methylisoborneol, which lower the quality of surface water when used for drinking. The results indicate that combined microautoradiography and CARD-FISH may serve as an effective tool when studying identity and activity of microorganisms within freshwater environments. [source] Plasma lipoprotein concentrations in the dog: the effects of gender, age, breed and dietJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 6 2008A. Pasquini Summary Earlier studies of canine lipoprotein metabolism have frequently not taken into account such variables as age, gender, lifestyle or feeding status. In the last years, many changes to lifestyle and feeding of dogs have occurred. In this study, C-tot, C-HDL, C-LDL, triglycerides and lipoprotein fractions were determined in 251 healthy dogs by means of enzymatic methods and through the electrophoretic technique. All data were analysed by multifactor anova test to determine which factors (age, gender, breed and diet) have a statistically significant effect (p < 0.05) on the determined parameter and subsequently Bonferroni's test was applied where necessary. Gender, age, breed and diet can significantly affect lipid metabolism, in particular lipoproteins involved in cholesterol plasma transport; on the contrary, triglycerides are not influenced by the same factors. The most important observation about age is the high level of C-LDL in puppies under 1 year of age. The highest cholesterol concentrations are found in Rottweiler but high values of plasma cholesterol are found also in Pyrenees Mountain dog and a great level of C-LDL in Labrador. Diet has shown a great influence on lipidic metabolism: dogs fed with different high-quality dry foods had significant differences in plasma cholesterol values (C-tot, C-HDL, C-LDL,), in particular, dogs fed with a diet rich in fish and fish-by-products have shown the lowest levels of C-tot, C-HDL and C-LDL. [source] The neuronal apoptotic death in global cerebral ischemia in gerbil: Important role for sodium channel modulator,JOURNAL OF NEUROSCIENCE RESEARCH, Issue 6 2009Manoja Kumar Brahma Abstract Global ischemia was induced in gerbil by bilateral occlusion of the common carotid arteries for 5 min. Sodium ionophore monensin or sodium channel blocker tetrodotoxin (TTX) was administered at doses of 10 ,g/kg, i.p., 30 min before ischemia induction; the dose was repeated after 22 hr. Subsequently, brain infarct occurred, determined at 24 hr after occlusion. Large, well-demarcated infarcts were observed in both hemispheres, an important observation because it critically influences the interpretation of the data. Because nitric oxide (NO) production is thought to be related to ischemic neuronal damage, we examined increases in Ca2+ influx, which lead to the activation of nitric oxide synthase (NOS). Then we evaluated the contributions of neuronal NOS, endothelial NOS, and inducible NOS to NO production in brain cryosections. The cytosolic release of apoptogenic molecules like cytochrome c and p53 were confirmed after 24 hr of reflow. TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling) labeling detected the apoptotic cells, which were confirmed in neuron-rich cell populations. After 24 hr, all the ischemic changes were amplified by monensin and significantly attenuated by TTX treatment. Additionally, the nesting behavior and histological outcomes were examined after 7 day of reflow. The neuronal damage in the hippocampal area and significant decrease in nesting scores were observed with monensin treatment and reduced by TTX pretreatment after day 7 of reflow. To our knowledge, this report is the first to highlight the involvement of the voltage-sensitive Na+ channel in possibly regulating in part NO system and apoptosis in a cytochrome c,dependent manner in global ischemia in the gerbil, and thus warrants further investigation. © 2008 Wiley-Liss, Inc. [source] Alcohol Up-Regulates TLR2 Through a NO/cGMP Dependent PathwayALCOHOLISM, Issue 1 2010Kristina L Bailey Background:, Heavy alcohol consumption is associated with severe bronchitis. This is likely related to increased inflammation in the airways of alcohol abusers. Toll-like receptor 2 (TLR2) is an important mediator of inflammation in the airway epithelium. TLR2 initiates an inflammatory cascade in response to gram-positive bacteria. We have previously shown that alcohol up-regulates TLR2 in the airway epithelium. However, the mechanism of alcohol-mediated up-regulation of TLR2 has not been identified. Methods:, A human airway epithelial cell line, 16HBE14o,, was exposed to biologically relevant concentrations of alcohol (100 mM) in the presence and absence of N, -Nitro- l -arginine methyl ester hydrochloride, a nitric oxide (NO) synthase inhibitor; and Rp-8-Br-cGMP-S, an antagonist analogue of cGMP. TLR2 was measured using real-time PCR and Western blots. In addition, 16HBE14o, cells were incubated with sodium nitroprusside (SNP), an NO donor, and 8-Br-cGMP, a cGMP analogue. TLR2 was measured using real-time PCR. Results:,N, -Nitro- l -arginine methyl ester hydrochloride blocked the alcohol-mediated up-regulation of TLR2. This indicates that NO plays a key role in alcohol's up-regulation of TLR2. SNP, a NO donor, up-regulated TLR2. Rp-8-Br-CGMP-S attenuated alcohol's up-regulation of TLR2, suggesting that NO was working through cGMP/PKG. 8-Br-cGMP up-regulated TLR2, also demonstrating the importance of cGMP/PKG. Conclusions:, Alcohol up-regulates TLR2 through a NO/cGMP/PKG dependent pathway in the airway epithelium. This is an important observation in the understanding how alcohol modulates airway inflammation. In addition, this is the first time that cyclic nucleotides have been shown to play a role in the regulation of TLR2. [source] Assessing in situ rates of anaerobic hydrocarbon bioremediationMICROBIAL BIOTECHNOLOGY, Issue 2 2009Lisa M. Gieg Summary Identifying metabolites associated with anaerobic hydrocarbon biodegradation is a reliable way to garner evidence for the intrinsic bioremediation of problem contaminants. While such metabolites have been detected at numerous sites, the in situ rates of anaerobic hydrocarbon decay remain largely unknown. Yet, realistic rate information is critical for predicting how long individual contaminants will persist and remain environmental threats. Here, single-well push,pull tests were conducted at two fuel-contaminated aquifers to determine the in situ biotransformation rates of a suite of hydrocarbons added as deuterated surrogates, including toluene- d8, o -xylene- d10, m -xylene- d10, ethylbenzene- d5 (or - d10), 1, 2, 4-trimethylbenzene- d12, 1, 3, 5-trimethylbenzene- d12, methylcyclohexane- d14 and n -hexane- d14. The formation of deuterated fumarate addition and downstream metabolites was quantified and found to be somewhat variable among wells in each aquifer, but generally within an order of magnitude. Deuterated metabolites formed in one aquifer at rates that ranged from 3 to 50 µg l,1 day,1, while the comparable rates at another aquifer were slower and ranged from 0.03 to 15 µg l,1 day,1. An important observation was that the deuterated hydrocarbon surrogates were metabolized in situ within hours or days at both sites, in contrast to many laboratory findings suggesting that long lag periods of weeks to months before the onset of anaerobic biodegradation are typical. It seems clear that highly reduced conditions are not detrimental to the intrinsic bioremediation of fuel-contaminated aquifers. [source] Low incidence of hepatic veno-occlusive disease in pediatric patients undergoing hematopoietic stem cell transplantation attributed to a combination of intravenous heparin, oral glutamine, and ursodiol at a single transplant institutionPEDIATRIC TRANSPLANTATION, Issue 5 2010Sonali Lakshminarayanan Lakshminarayanan S, Sahdev I, Goyal M, Vlachos A, Atlas M, Lipton JM. Low incidence of hepatic veno-occlusive disease in pediatric patients undergoing hematopoietic stem cell transplantation attributed to a combination of intravenous heparin, oral glutamine, and ursodiol at a single transplant institution. Pediatr Transplantation 2010: 14:618,621. © 2009 John Wiley & Sons A/S. Abstract:, We report the low incidence of hepatic VOD in pediatric patients with various diagnoses including hematologic malignancies and non-malignant conditions transplanted at our institution. Retrospective review of 188 patients who underwent HSCT and received a combined prophylactic regimen of intravenous heparin, oral glutamine, and ursodiol was undertaken. Analysis of the outcome of VOD revealed only one clinical case with acute myeloid leukemia; the patient developed hepatic VOD 10 days after receiving myeloablative chemotherapy with busulfan and CTX followed by HLA-matched related peripheral blood stem cell transplantation. The low incidence of hepatic VOD in an otherwise high-risk pediatric transplant population is an important observation, which may be partly attributed to this prophylactic regimen, and warrants further randomized clinical trials for confirmation. [source] Poster 1, Haemorrhagic bullae in a child with Henoch,Schönlein purpuraBRITISH JOURNAL OF DERMATOLOGY, Issue 6 2007S. Abdul-Ghaffar Henoch,Schönlein purpura (HSP) is one of the most common types of vasculitis in children. It usually presents with purpura, abdominal pain, arthralgia/arthritis and nephritis. The purpura seen in HSP is typically petechial or target-like and is the presenting sign in 50% of patients. Haemorrhagic bullae are rarely reported in children. We describe a 10-year-old boy who presented with a 1-week history of a petechial rash on his legs and buttocks, associated with abdominal pain and tender, swollen ankles and knees in May 2006. He had a history of a preceding upper respiratory tract infection. A clinical diagnosis of HSP was made at this stage. However, the rash became more extensive, involving his arms, shoulders and ears. Within 2 weeks, large tense haemorrhagic bullae developed on the lower legs, feet and hands. Urinalysis was positive for blood and protein but his blood pressure and renal function were normal. The rest of his investigations, including a full vasculitis screen, were normal. Because of the atypical bullae, a skin biopsy was performed. This showed leucocytoclastic vasculitis with IgA deposition consistent with HSP. The lesions improved with prednisolone, starting at 2 mg kg,1 daily, gradually reducing the dose over 3 months. Bullous HSP has been seen in up to 60% of adult patients but only in 2% of children. There have been only 11 reported cases of bullous HSP to date and the commonest sites were feet, ankles, legs and buttocks, suggesting that pressure is the most likely factor in its pathogenesis. This is an important observation as the presence of these atypical bullous lesions may pose a diagnostic challenge. [source] Inhibition of TRPM2 function by PARP inhibitors protects cells from oxidative stress-induced deathBRITISH JOURNAL OF PHARMACOLOGY, Issue 5 2004Barbara A Miller TRPM2 is a member of the transient receptor potential (TRP) protein superfamily of calcium-permeable, voltage-independent ion channels expressed in nonexcitable cells. Activation of TRPM2 by oxidative stress results in calcium influx and susceptibility to cell death, whereas inhibition of TRPM2 function enhances cell survival. In the present edition of this journal, Fonfria et al. demonstrate a role for poly(ADP ribose) polymerase (PARP) as a mediator between oxidative stress and TRPM2 activation. They present evidence that inhibition of either PARP or TRPM2 protects cells from plasma membrane damage and cell death. The therapeutic implications of this important observation are discussed. British Journal of Pharmacology (2004) 143, 515,516. doi:10.1038/sj.bjp.0705923 [source] The Sensitivity of Canadian Corporate Investment to LiquidityCANADIAN JOURNAL OF ADMINISTRATIVE SCIENCES, Issue 3 2000Sean Cleary This study examines the investment behaviour of 201 Canadian firms over the 1987-94 period and confirms that liquidity is a significant determinant of Canadian corporate investment. Contrary to recent US evidence, the investment-liquidity sensitivity of financially constrained firms is not found to be significantly different from that of unconstrained firms. Surprisingly, partially constrained firms exhibit higher investment-liquidity sensitivity than both constrained and unconstrained firms. The difference from the US results is attributed to the industry structure and closely held nature of Canadian firms. Finally, this study highlights the importance of sample size by demonstrating how sensitive the results can be to the behaviour of a small number of firms. This represents an important observation, since the conclusions of several previous studies are based on small sample results. Résumé Cette étude passe en revue la gestion des investissements de 201 sociétés canadiennes durant les années 1987-94 et confirme que, en ce qui concerne le milieu d'affaires canadien, la liquidité est un facteur important dans la mise de fonds. Contrairement aux données récentes provenant des EU, l'importance de la liquidité des placements chez les maisons de commerce sous con-traintes fiscales ne s'avère pas ,tre très différente de celle chez les maisons sans pareilles contraintes. De façon surprenante, les maisons sous contraintes fiscales partielles démontrent une sensibilité plus accrue à la liquidité des placements que les maisons davantage contraintes, ou encore sans aucune contrainte. L'écart entre ces données et celles provenant des EU s'explique en fonction de l'organisation industrielle et de la plus haute concentration des actionnaires dans les maisons de commerce canadiennes. Enfin, cette étude souligne l'importance de l'ampleur de l'échantillonage en démontrant à quel point les données peuvent varier en fonction d'un nombre restraint de maisons de commerce. Etant donné que les conclusions de plusieurs études précédentes étaient tirées d'échantillonages plus restreints, cette observation gagne en portée. [source] Training and public sector reform: an integrated approachPUBLIC ADMINISTRATION & DEVELOPMENT, Issue 4 2001Padraig Healy This article is partly a response to McCourt and Sola (1999), who raised a number of important observations about the role and limitations of training in promoting public sector reform in Tanzania. In particular, their discussion of the relationship between individual and organizational change is referred to. The article outlines a possible alternative to the straight training approach to capacity building, and suggests it as a possible model for the kind of OD intervention mentioned in McCourt and Sola, The author describes a programme of capacity building for rural district councils in Zimbabwe, which tried to avoid the mistakes of earlier public sector training programmes. In discussing ways of integrating human resource development into programmes of capacity building and public sector reform, the article adds to the debate about process and blueprint approaches as discussed in this journal by Cook, (1997), Blunt (1997) and others. The article concludes with an attempt to assess some of the achievements and failures of the training programme after the initial three years. It draws attention to some of the external factors in the programme operating environment which combine with the internal coordination and management aspects, in determining the overall achievement of such a complex programme. Copyright © 2001 John Wiley & Sons, Ltd. [source] An adaptive buddy check for observational quality controlTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 577 2001Dick P. Dee Abstract An adaptive buddy-check algorithm is presented that adjusts tolerances for suspect observations, based on the variability of surrounding data. The algorithm derives from a statistical hypothesis test combined with maximum-likelihood covariance estimation. Its stability is shown to depend on the initial identification of outliers by a simple background check. The adaptive feature ensures that the final quality-control decisions are not very sensitive to prescribed statistics of first-guess and observation errors, nor on other approximations introduced into the algorithm. The implementation of the algorithm in a global atmospheric data assimilation is described. Its performance is contrasted with that of a non-adaptive buddy check, for the surface analysis of an extreme storm that took place over Europe on 27 December 1999. The adaptive algorithm allowed the inclusion of many important observations that differed greatly from the first guess and that would have been excluded on the basis of prescribed statistics. The analysis of the storm development was much improved as a result of these additional observations. [source] | |||||||||||||