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Conventional
Terms modified by Conventional Selected AbstractsP-26 CONVENTIONAL V THIN LAYER TECHNIQUES: A COMPARATIVE STUDY OF BRONCHIAL SPECIMENS USING CONVENTIONAL AND TWO LBC METHODS, THINPREP AND SUREPATHCYTOPATHOLOGY, Issue 2006J. L. Conachan The current, conventional method used is quick, easy and reasonably cheap but the nature of bronchial specimens themselves creates the need for a better preparation technique. Bronchial specimens often present with many obscuring features, such as blood and mucus, which can affect definitive diagnosis. In the study, the bronchial specimens underwent routine conventional preparation and that remaining was used to prepare an LBC slide. Both LBC methods were separately evaluated alongside the conventional method where, of the 44 specimens used, half were prepared using the conventional and ThinPrep and half with the conventional and SurePath. Evaluation forms were completed by pathologists who assessed all preparations. The results showed both LBC methods produced superior preparations that were better fixed, more cellular and had improved nuclear detail. They also removed a high percentage of background debris, were more diagnostically accurate and reduced the inadequate rate by a third. The conventional slides prepared from the same specimen as the SurePath had a lower average than those prepared with the ThinPrep. This indicated that the specimens used to evaluate the SurePath method were in fact inferior to those used for ThinPrep, with the SurePath slides showing only a slight improvement in overall quality. Despite LBC preparations reducing pathologist screening and reporting time, both methods are more labour intensive and less cost effective. The majority of laboratories are not in the financial situation to trial new methods that require extra training and more staff hours, and as such this study has highlighted an important question ,Do the benefits of better quality preparation and diagnostic accuracy offset an increase in time and cost'. [source] Predicting survival of grass shrimp (Palaemonetes pugio) exposed to naphthalene, fluorene, and dibenzothiophene,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2008Michael A. Unger Abstract The composition and persistence of dissolved polycyclic aromatic hydrocarbons (PAHs) released to the water column during oil spills are altered by weathering, tidal transport, and addition of dispersants. Conventional toxicity effect metrics, such as the median lethal concentration (LC50), are inaccurate predictors of mortality from all toxicant exposure duration/concentration combinations likely to occur during spills. In contrast, survival models can predict the proportions of animals dying as a consequence of exposures differing in duration and intensity. Extending previous work with ethylnaphthalene, dimethylnaphthalene, and phen-anthrene, survival time models were developed that include exposure duration and concentration to predict time to death for grass shrimp (Palaemonetes pugio). Two additional PAHs (naphthalene and fluorene) and a heterocyclic aromatic hydrocarbon (dibenzothiophene) were evaluated for the present study. Preliminary explorations of these models confirmed that quantitative structure-activity regression models were possible for predicting survival model parameters from compound characteristics. Conventional 48-h LC50s also were calculated for the compounds and combined with published LC50s to predict relative PAH toxicity to P. pugio based on octanol-water partitioning. [source] Diffusion-tensor MR imaging for evaluation of the efficacy of hyperbaric oxygen therapy in patients with delayed neuropsychiatric syndrome caused by carbon monoxide inhalationEUROPEAN JOURNAL OF NEUROLOGY, Issue 7 2007C.-P. Lo The purpose of this study is to assess the efficacy of hyperbaric oxygen therapy (HBOT) in patients with delayed neuropsychiatric syndrome (DNS) caused by carbon monoxide (CO) inhalation using diffusion tensor magnetic resonance (MR) imaging and neuropsychological test. Conventional and diffusion tensor brain MR imaging exams were performed in six patients with DNS immediately before and 3 months after the HBOT to obtain fractional anisotropy (FA) values. Six age- and sex-matched normal control subjects also received MR exams for comparison. Mini-Mental State Examination (MMSE) was also performed in patients immediately before and 3 months after the HBOT. A significantly higher mean FA value was found in control subjects as compared with the patients both before and 3 months after the HBOT (P < 0.001). The mean FA value 3 months after the HBOT was also significantly higher than that before the HBOT in the patient group (P < 0.001). All of the patients regained full scores in the MMSE 3 months after the HBOT. Diffusion tensor MR imaging can be a quantitative method for the assessment of the white matter change and monitor the treatment response in patients of CO-induced DNS with a good clinical correlation. HBO may be an effective therapy for DNS. [source] Process Cost Comparison for Conventional and Near-Net-Shape Cermet Fabrication,ADVANCED ENGINEERING MATERIALS, Issue 3 2010Yuhong Xiong Tungsten carbide,cobalt (WC,Co) is a widely used cermet that is generally fabricated into bulk parts via conventional powder metallurgy (P/M) methods. Because this material (and other cermets) is very hard and wear resistant, diamond grinding is generally required to fabricate complex parts. As an alternative, studies have shown the Laser Engineering Net Shaping (LENS) process to be a technically feasible method, allowing for fabrication of near-net-shape parts. The economic trade-offs, however, have not been previously characterized. In this work, technical cost modeling (TCM) is applied to compare the costs of fabricating WC,Co parts with the P/M process to those of the LENS process. Cost drivers are identified and sensitivity analysis is conducted. Results reveal that the uncertainty in functional unit has a significant effect on relative process costs, and the cost is sensitive to order size only if less than ten parts are produced. It is concluded that the LENS process is economically preferable if part size is small or part shape is complex. The P/M process is more suitable to produce large parts in simple shapes. [source] PE-UHMW in Hip Implants: Properties of Conventional and Crosslinked Prosthetic ComponentsADVANCED ENGINEERING MATERIALS, Issue 10 2009Ruth Markut-Kohl Hip implants made of crosslinked ultra high molecular weight polyethylene,PE-UHMW,(different as-received conditions) are compared with a retrieval made from non-crosslinked PE-UHMW and a control PE-UHMW. Oxidation leads to recrystallization and the enhanced crystallinity corresponds to higher hardness values. These structure-property relations are discussed for conventional PE-UHMW and also for crosslinked material. [source] Evaluating the physiological and physical consequences of capture on post-release survivorship in large pelagic fishesFISHERIES MANAGEMENT & ECOLOGY, Issue 2 2007G. B. SKOMAL Abstract, Sharks, tunas and billfishes are fished extensively throughout the world. Domestic and international management measures (quotas, minimum sizes, bag limits) mandate release of a large, yet poorly quantified, number of these fishes annually. Post-release survivorship is difficult to evaluate, because standard methods are not applicable to large oceanic fishes. This paper presents information on the current approaches to characterising capture stress and survivorship in sharks, tunas and marlins. To assess mortality associated with capture stress, researchers must examine the cumulative impacts of physical trauma and physiological stress. Physical trauma, manifested as external and internal tissue and organ damage, is caused by fishing gear and handling. Gross examination and histopathological sampling have been used to assess physical trauma and to infer post-release survivorship. Exhaustive anaerobic muscular activity and time out of water cause physiological stress, which has been quantified in these fishes through the analyses of blood chemistry. Conventional, acoustic and archival tagging have been used to assess post-release survivorship in these species. Future studies relating capture stress and post-release survivorship could yield information that helps fishermen increase survivorship when practicing catch and release. [source] Conventional versus complementary treatment of back pain, depression, hypertension and asthma in primary care: patient's view of outcomesFOCUS ON ALTERNATIVE AND COMPLEMENTARY THERAPIES AN EVIDENCE-BASED APPROACH, Issue 2004F Marian [source] Conventional and integrative medicine , evidence based?FOCUS ON ALTERNATIVE AND COMPLEMENTARY THERAPIES AN EVIDENCE-BASED APPROACH, Issue 1 2003Sorting fact from fiction [source] Dynamic versus static models in cost-effectiveness analyses of anti-viral drug therapy to mitigate an influenza pandemicHEALTH ECONOMICS, Issue 5 2010Anna K. Lugnér Abstract Conventional (static) models used in health economics implicitly assume that the probability of disease exposure is constant over time and unaffected by interventions. For transmissible infectious diseases this is not realistic and another class of models is required, so-called dynamic models. This study aims to examine the differences between one dynamic and one static model, estimating the effects of therapeutic treatment with antiviral (AV) drugs during an influenza pandemic in the Netherlands. Specifically, we focus on the sensitivity of the cost-effectiveness ratios to model choice, to the assumed drug coverage, and to the value of several epidemiological factors. Therapeutic use of AV-drugs is cost-effective compared with non-intervention, irrespective of which model approach is chosen. The findings further show that: (1) the cost-effectiveness ratio according to the static model is insensitive to the size of a pandemic, whereas the ratio according to the dynamic model increases with the size of a pandemic; (2) according to the dynamic model, the cost per infection and the life-years gained per treatment are not constant but depend on the proportion of cases that are treated; and (3) the age-specific clinical attack rates affect the sensitivity of cost-effectiveness ratio to model choice. Copyright © 2009 John Wiley & Sons, Ltd. [source] Conventional and unconventional approaches to exchange rate modelling and assessmentINTERNATIONAL JOURNAL OF FINANCE & ECONOMICS, Issue 1 2008Ron Alquist Abstract We examine the relative predictive power of the sticky price monetary model, uncovered interest parity, and a transformation of net exports and net foreign assets. In addition to bringing Gourinchas and Rey's new approach and more recent data to bear, we implement the Clark,West procedure for testing the significance of out-of-sample forecasts. The interest rate parity relation holds better at long horizons and the net exports variable does well in predicting exchange rates at short horizons in sample. In out-of-sample forecasts, we find evidence that our proxy for Gourinchas and Rey's measure of external imbalances outperforms a random walk at short horizons as do some of the other models, although no single model uniformly beats the random walk forecast. Copyright © 2007 John Wiley & Sons, Ltd. [source] Conventional versus resin-modified glass-ionomer cement for Class II restorations in primary molars.INTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 1 2003A 3-year clinical study Summary. Objective. To compare the clinical performance of two glass-ionomer cements (GICs)for Class II restorations in primary molars: a conventional cement (Fuji II®) and a resin-modified cement (Vitremer®). Design. Split mouth and random assignment to the two materials were used for the majority of the molars. Sample and methods. Forty consecutive 4,7-year-old children were included. One operator made 115 restorations: 53 with Vitremer and 62 with Fuji II. The restorations were evaluated clinically, radiographically and from colour photographs. Results. The cumulative success rate of the Vitremer restorations was 94% and that of the Fuji II restorations 81%. The difference is statistically significant. The risk of a failed restoration was more than five times higher with Fuji II than with Vitremer as the restorative material. Of the 13 unsuccessful restorations, seven had lost their retention, four had secondary caries, and two were fractured. Conclusions. The resin-modified GIC offered advantages over the conventional GIC for restoring approximal caries in primary molars. [source] On the Segregation of Genetically Modified, Conventional and Organic Products in European Agriculture: A Multi-market Equilibrium AnalysisJOURNAL OF AGRICULTURAL ECONOMICS, Issue 3 2005GianCarlo Moschini Q1; O3 Abstract Evaluating the possible benefits of the introduction of genetically modified (GM) crops must address the issue of consumer resistance as well as the complex regulation that has ensued. In the European Union (EU), this regulation envisions the co-existence of GM food with conventional and quality-enhanced products, mandates the labelling and traceability of GM products and allows only a stringent adventitious presence of GM content in other products. All these elements are brought together within a partial equilibrium model of the EU agricultural food sector. The model comprises conventional, GM and organic food. Demand is modelled in a novel fashion, whereby organic and conventional products are treated as horizontally differentiated but GM products are vertically differentiated (weakly inferior) relative to conventional ones. Supply accounts explicitly for the land constraint at the sector level and for the need for additional resources to produce organic food. Model calibration and simulation allow insights into the qualitative and quantitative effects of the large-scale introduction of GM products in the EU market. We find that the introduction of GM food reduces overall EU welfare, mostly because of the associated need for costly segregation of non-GM products, but the producers of quality-enhanced products actually benefit. [source] Comparison of 16S rRNA sequencing with conventional and commercial phenotypic techniques for identification of enterococci from the marine environmentJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2006D.F. Moore Abstract Aims:, To compare accuracy of genus and species level identification of presumptive enterococci isolates from the marine environment using conventional biochemical testing, four commercial identification systems and 16S rRNA sequence analysis. Methods and Results:, Ninety-seven environmental bacterial isolates identified as presumptive enterococci on mEI media were tested using conventional and Enterococcus genus screen biochemical tests, four commercial testing systems and 16S rRNA sequencing. Conventional and Enterococcus genus screen biochemical testing, 16S rRNA sequencing and two commercial test systems achieved an accuracy of ,94% for Enterococcus genus confirmation. Conventional biochemical testing and 16S rRNA sequencing achieved an accuracy of ,90% for species level identification. Conclusions:, For confirmation of Enterococcus genus from mEI media, conventional or genus screen biochemical testing, 16S rRNA sequencing and the four commercial systems were correct 79,100% of the time. For speciation to an accuracy of 90% or better, either conventional biochemical testing or 16S rRNA sequencing is required. Significance and Impact of the Study:, Accurate identification of presumptive environmental Enterococcus isolates to genus and species level is an integral part of laboratory quality assurance and further characterization of Enterococcus species from pollution incidents. This investigation determines the ability of six different methods to correctly identify environmental isolates. [source] Nanostructure and micromechanical properties of reversibly crosslinked isotactic polypropylene/clay compositesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2010S. Bouhelal Abstract Recent developments concerning the methodology used to prepare composites of iPP and nanoclays are reported. Conventional (reactive melt mixing) and in situ preparations were performed, and the structural properties exhibited by the composites are discussed. Results suggest that the nanoclay could exhibit partial and, maybe, total exfoliation within the composites. Adhesion between the polymeric matrix and the nanoclay layers is similar to that obtained after grafting. The experimental procedure used and the analysis performed by means of the wide-angle X-ray scattering and differential scanning calorimetry techniques permit to describe, at nanoscale level, the contribution of the nanoclay to the polymer composite system. The microhardness values of the iPP,clay composites depend on the clay content and on the preparation method, and linearly correlate, according to the additivity law, with the degree of crystallinity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Esthetic Correction of Anterior Dental Malalignment: Conventional versus Instant (Restorative) OrthodonticsJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 3 2004FRANK M. SPEAR DDS ABSTRACT Over the past 20 years since its introduction, adhesive dentistry has suffered, at times, from overuse, particularly in patients with problems of malalignment for which conventional orthodontics would once have been used. The purpose of this article is to create a "flow sheet" to aid decision making regarding whether conventional orthodontics should be used, and what the limitations of treating a patient are if treatment is performed without any orthodontics. [source] Seasonal foraging movements and migratory patterns of female Lamna ditropis tagged in Prince William Sound, AlaskaJOURNAL OF FISH BIOLOGY, Issue 2 2005L. B. Hulbert Conventional and electronic tags were used to investigate social segregation, distribution, movements and migrations of salmon sharks Lamna ditropis in Prince William Sound, Alaska. Sixteen salmon sharks were tagged with satellite transmitters and 246 with conventional tags following capture, and were then released in Prince William Sound during summer 1999 to 2001. Most salmon sharks sexed during the study were female (95%), suggesting a high degree of sexual segregation in the region. Salmon sharks congregated at adult Pacific salmon Oncorhynchus spp. migration routes and in bays near Pacific salmon spawning grounds in Prince William Sound during July and August. Adult Pacific salmon were the principal prey in 51 salmon shark stomachs collected during summer months in Prince William Sound, but the fish appeared to be opportunistic predators and consumed sablefish Anoplopoma fimbria, gadids, Pacific herring Clupea pallasi, rockfish Sebastes spp. and squid (Teuthoidea) even when adult Pacific salmon were locally abundant. As Pacific salmon migrations declined in late summer, the salmon sharks dispersed; some continued to forage in Prince William Sound and the Gulf of Alaska into autumn and winter months, while others rapidly moved south-east thousands of kilometres toward the west coasts of Canada and the U.S. Three movement modes are proposed to explain the movement patterns observed in the Gulf of Alaska and eastern North Pacific Ocean: ,focal foraging' movements, ,foraging dispersals' and ,direct migrations'. Patterns of salmon shark movement are possibly explained by spatio-temporal changes in prey quality and density, an energetic trade-off between prey availability and water temperature, intra-specific competition for food and reproductive success. Transmissions from the electronic tags also provided data on depth and water temperatures experienced by the salmon sharks. The fish ranged from the surface to a depth of 668 m, encountered water temperatures from 4·0 to 16·8° C and generally spent the most time above 40 m depth and between 6 and 14° C (60 and 73%, respectively). [source] The Effect of Electric Field on Important Food-processing Enzymes: Comparison of Inactivation Kinetics under Conventional and Ohmic HeatingJOURNAL OF FOOD SCIENCE, Issue 9 2004I. Castro ABSTRACT: This work deals with the determination of the inactivation kinetics of several enzymes, most of them used as time-temperature integrators in the food industry. The tested enzymes were polyphenoloxidase, lipoxygenase, pectinase, alkaline phosphatase, and p-galactosidase, and the inactivation assays were performed under conventional and ohmic heating conditions. The thermal history of the samples (conventional and ohmically processed) was made equal to determine if there was an additional inactivation caused by the presence of an electric field, thus eliminating temperature as a variable. All the enzymes followed 1st-order inactivation kinetics for both conventional and ohmic heating treatments. The presence of an electric field does not cause an enhanced inactivation to alkaline phosphatase, pectinase, and ,- galactosidase. However, lipoxygenase and polyphenoloxidase kinetics were significantly affected by the electric field, reducing the time needed for inactivation. The results of the present work can be used industrially to determine processing effectiveness when ohmic heating technology is applied. [source] Crime scene actions and offender characteristics in a sample of Finnish stranger rapesJOURNAL OF INVESTIGATIVE PSYCHOLOGY AND OFFENDER PROFILING, Issue 1 2004Helinä Häkkänen Abstract The crime scene actions employed by offenders in stranger rapes were analysed in relation to offender characteristics. Data were drawn from an official police database and consisted of stranger rapes occurring in Finland between 1992 and 2001 (n,=,100). The structure of dichotomous variables derived through a content analysis of crime scene actions and offender characteristics were analysed with non-metric multidimensional scaling (MDS). The first analysis revealed three separate action themes, with thematic emphases on Hostility, Involvement or Theft. The MDS-solution for offender characteristics suggested four themes: Conventional; Psychiatric/Elderly; Criminal/Violent; and Criminal/Property. Each case was assigned to one of the themes or as a hybrid in order to analyse the associations between action themes and characteristics. The only significant association was found between the action theme, Theft and characteristics theme Criminal/Property. The results are discussed in relation to previous research. Copyright © 2004 John Wiley & Sons, Ltd. [source] Tooth Preparation: A Study on the Effect of Different Variables and a Comparison Between Conventional and Channeled Diamond BursJOURNAL OF PROSTHODONTICS, Issue 1 2004Daniel F. Galindo DDS Purpose: The purpose of this study was to evaluate the different variables involved in tooth cutting to characterize intrapulpal temperature generation, cutting efficiency, and bur durability when using conventional and channeled diamond burs. Materials and Methods: Forty premolars and 60 molars were selected for the study. Four diamond burs were paired according to grit size: 125- ,m grit: Brasseler Coarse (Control 1) and TDA System (Test 1) burs; and 180- ,m grit: Brasseler CRF (Control 2) and NTI Turbo Diamond (Test 2) burs. Each bur was used twice when cutting the premolar teeth, whereas it was used for 60 cuts when cutting the molar teeth. The data were analyzed to compare the correlation of bur design, grit and wear, amount of pressure, advancement rate, revolutions per minute, cutting time and rate, and proximity to the pulp chamber with intrapulpal temperature generation, cutting efficiency, and bur longevity. The mean values of test and control burs in each group were compared using an ANOVA (p < 0.05 for significant differences) for temperature generation and an ANOVA and the Tukey multiple range test (p, 0.05) for cutting efficiency and bur longevity. Results: No significant difference was found in intrapulpal temperature generation while cutting premolar and molar teeth with conventional and channeled diamond burs. In both groups, the mean temperature recorded during and after the cutting procedure was lower than the baseline temperature. For premolar teeth, no significant difference was established for control and test burs for the load required to cut into the tooth and the cutting rate. However, both test burs showed significantly fewer revolutions per minute when compared to their control counterparts. For the molar teeth, the Brasseler CRF bur required a significantly lower cutting load when compared to the NTI bur, whereas no difference was noted between the other pair of burs. The cutting rate was significantly higher for both control burs, whereas revolutions per minute (rpm) were greater for control coarser burs only. Overall, channeled burs showed a significantly lower cutting efficiency when compared to conventionally designed burs. Conclusion: Within the limitations of this study, channeled burs showed no significant advantage over conventional diamond burs when evaluating temperature generation and bur durability. Moreover, the cutting efficiency of conventional burs was greater than that of channeled burs. [source] Stimulating or conventional perineural catheters after hallux valgus repair: a double-blind, pharmaco-economic evaluationACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 10 2006A. Casati Background:, We prospectively evaluated direct analgesia-related costs of continuous sciatic nerve block using either a stimulating or conventional catheter after hallux valgus repair. Methods:, The perineural catheter was inserted through a stimulating introducer either blindly (group Conventional, n= 38) or while stimulating via the catheter (group Stimulating, n= 38). Nerve block was induced with 25 ml of mepivacaine 15 mg/ml, and was followed 3 h later by a patient-controlled infusion of ropivacaine 2 mg/ml (basal infusion: 3 ml/h; incremental dose: 5 ml; lock-out time: 30 min). Rescue tramadol [100 mg intravenous (i.v.)] was given if required. Local anesthetic consumption, need for rescue tramadol and post-operative nausea and vomiting (PONV) treatment, and patient's satisfaction were recorded during first 24-h infusion. Cost calculations were based on the acquisition cost of drugs and devices. Results:, Both techniques were similarly effective, but local anesthetic consumption and need for rescue analgesics were lower in the Stimulating group [respectively, 120 vs. 153 ml (P= 0.004) and 21% vs. 60% (P= 0.001)]. The analgesia-related costs for 24 h were similar when 100-ml bags of ropivacaine 2 mg/ml were used (66 , vs. 67 ,; P= 0.26). When 200-ml bags of ropivacaine were used, the analgesia-related costs were higher in the Stimulating group than the Conventional group (75 , vs. 55 ,; P= 0.0005). Conclusions:, Direct costs of continuous sciatic nerve block ranged from 55 to 75 ,. Stimulating catheters reduced local anesthetic consumption and need for rescue analgesics. This was only cost effective when 100-ml bags of 2 mg/ml ropivacaine were used, while the cheapest combination was the use of conventional catheters and 200-ml bags of ropivacaine. [source] Conversion to Silodosin in Men on Conventional ,1 -Blockers for Symptomatic Benign Prostatic HyperplasiaLUTS, Issue 1 2010Masahiko TANAKA Objectives:,1 -blockers have commonly been used as first-line medical therapy for symptomatic benign prostatic hyperplasia (BPH). Recently, a highly selective ,1A -adrenoceptor antagonist, silodosin, was developed in Japan. We examined the efficacy and safety of conversion from conventional ,1 -blockers to silodosin in men with BPH. Methods: Conversion to silodosin was proposed to consecutive patients on conventional ,1 -blockers for symptomatic BPH for at least 6 months. The effects of conversion were examined by the International Prostate Symptom Score, quality of life index, overactive bladder symptom score, peak flow rate, residual urine volume, and adverse events at 12 weeks. The efficacy of silodosin was also evaluated by patients' impression. Results: Eighty-one men underwent conversion, for the most part because of dissatisfaction with the efficacy of their current treatment in improving nocturia or weak stream. The International Prostate Symptom Score total score significantly improved from 12.7 ± 5.9 at baseline to 10.6 ± 5.4 at 4 weeks (P < 0.001) and 10.9 ± 5.8 at 12 weeks (P < 0.01). The progress was mostly due to improvement in voiding symptoms, although reduction of storage symptoms was also significant. The quality of life index also significantly decreased with conversion to silodosin. Efficacy as judged by patients' impression was 76% (37/49) at 12 weeks of treatment. None of the overactive bladder symptom score, peak flow rate, and residual urine volume exhibited significant change. No serious adverse events were observed during the study period. Conclusion: Conversion to silodosin may be beneficial in men who are dissatisfied with conventional ,1 -blockers for BPH, and be particularly useful in improving voiding symptoms. [source] Overdrive Versus Conventional or Closed-Loop Rate Modulation Pacing in the Prevention of Atrial Tachyarrhythmias in Brady-Tachy Syndrome: On Behalf of the Burden II Study GroupPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 11 2008ANDREA PUGLISI M.D. Background:Optimizing dual-chamber pacing to prevent recurrences of atrial tachyarrhythmias (AT) in sinus node dysfunction is still debated. Despite the large number of studies, efficacy of sophisticated preventive algorithms has never been proven. It is not clear whether this is due to imperfect study designs or to a substantial inefficacy of pacing therapies. Aim:To intraindividually compare AT burden between an atrial overdrive and two heart rate modulation approaches: a conventional accelerometric-sensor-based DDDR mode and a contractility-driven rate responsive closed loop (CLS) algorithm. Methods and Results:Four hundred fifty-one patients with Brady-Tachy syndrome (BTS), severe bradycardia, and a documented episode of atrial fibrillation were enrolled. One month after implant, each pacing therapy was activated for 3 months in random order. A simple log transformation was used to handle large and skew AT burden distributions. Estimates were adjusted for false-positive AT episodes and reported as geometric means (95% confidence interval). A significantly higher AT burden was observed during overdrive, 0.14% (0.09%, 0.23%) (adjusted, 0.12%[0.07%, 0.20%]). Both DDDR and CLS performed better: respectively, 0.11% (0.07%, 0.17%) (adjusted, 0.08%[0.05%, 0.14%]), 0.06% (0.03%, 0.09%) (adjusted, 0.04%[0.03%, 0.07%]). All the comparisons were statistically significant. During overdrive significantly more patients had AT episodes of duration between 1 minute and 1 hour. No significant differences were observed for longer episodes. Conclusions:Atrial overdrive showed the worst performance in terms of AT burden reduction and should not be preferred to heart rate modulation approaches that still have to be considered as a first-choice pacing mode in BTS. [source] Improvement of Congestive Heart Failure by Upgrading of Conventional to Resynchronization PacemakersPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2006IBRAHIM MARAI Aims: To compare the clinical response of patients with right ventricular apical pacing (RVAP) upgraded to cardiac resynchronization therapy (CRT) to that of previously nonpaced heart failure (HF) patients who had de novo CRT implantation. Background: The role of CRT in patients with wide QRS and HF due to RVAP is less well established than in other CRT candidates. Methods: Ninety-eight consecutive patients with CRT were studied (mean age 70, mean ejection fraction 0.23). Group A: patients having RVAP prior to CRT implantation (n = 25), group B: patients without prior RVAP (n = 73). Clinical and echocardiographic parameters were recorded prior to, and 3 months after, CRT implantation. Results: Group A patients had a wider QRS at baseline compared to group B (203 ± 32 ms vs 163 ± 30 ms respectively, P < 0.001), and a shorter 6-minute walking distance (222 ± 118 m vs 362 ± 119 m, respectively, P < 0.005). Otherwise, clinical and echocardiographic parameters were not different. At follow up, group A patients had an average 0.7 ± 0.5 decrease in their NYHA functional class, compared to 0.3 ± 0.7 in group B patients (P < 0.05). Six-minute walking distance increased by 93 ± 113 m in group A, versus 36 ± 120 m in group B (P = 0.22). There was no difference in echocardiographic response to CRT between the groups. Conclusions: HF patients with prior RVAP demonstrate clinical improvement after upgrading to CRT that is comparable, and in some aspects, even better than that observed in HF patients with native conduction delay who undergo de novo CRT implantation. [source] The effect of low-carbohydrate diet on left ventricular diastolic function in obese childrenPEDIATRICS INTERNATIONAL, Issue 2 2010Cenap Zeybek Abstract Background:, This study was conducted to evaluate left ventricle (LV) functions using conventional and tissue Doppler imaging in childhood obesity and to identify the effects of diet on LV diastolic functions. Methods:, Conventional and tissue Doppler echocardiographic measurements were compared in 34 obese children and 24 age- and gender-matched lean controls. Fasting plasma glucose, insulin and homeostatic model assessment of insulin resistance levels were also obtained. Thirty-one of the obese children were subjected to a low-carbohydrate diet and their follow-up measurements were obtained after 6 months. Results:, Left atrial diameter, LV mass and LV mass index were higher in obese children than in lean controls. Lateral mitral myocardial early diastolic (Em) and peak Em/myocardial late diastolic (Am) were lower, and mitral E/Em and lateral mitral myocardial isovolumetric relaxation time were higher in obese subjects than in lean controls. Insulin and homeostatic model assessment of insulin resistance levels were higher in obese patients and decreased significantly after diet. After diet therapy, lateral mitral Em and peak Em/Am, were increased, mitral E/Em and myocardial isovolumetric relaxation time were decreased. Conclusions:, Obesity predisposes children to increased preload reserve, left ventricular subclinical diastolic dysfunction and deterioration in diastolic filling. Weight reduction with a low-carbohydrate diet seems to be associated with significant improvement in LV diastolic function and a decrease in diastolic filling, as well as causing reversal in insulin resistance seen in obese children. [source] Conventional and nanometric nucleating agents in poly(,-caprolactone) foaming: Crystals vs. bubbles nucleationPOLYMER ENGINEERING & SCIENCE, Issue 2 2008Carlo Marrazzo The aim of this article was to investigate the nucleating ability of different nucleating agents for the foaming of poly(,-caprolactone), a biodegradable, semicrystalline polymer. In particular, the efficiency of the nucleating agent in inducing the formation of the gaseous phase has been compared to the efficiency in inducing the formation of the crystalline phase. In effect, in foaming of semicrystalline polymers, bubble nucleation and crystal nucleation are concurrent and somehow interacting phenomena. Here, these two aspects have been evidenced and clarified. Foams were prepared by using a batch process with the pressure quench method, with nitrogen and carbon dioxide as the blowing agents. Conventional and novel nucleating agents were used: talc has been compared to several novel nanometric particles of different geometries and dimensions, such as titanium dioxide and alumina powders, exfoliated and intercalated clays, and carbon nanotubes. Foam densities and morphologies, in terms of number of cells per initial unit volume, were measured and found to depend both on crystalline phase nucleation and gaseous phase nucleation. In fact, the different nucleating agents, depending on shape, dimension, and surface functionalization, selectively nucleated the crystallites and/or the bubbles, affecting, respectively, bubble growth (and, hence, final foam density) and bubble nucleation (and, hence, cell number density,morphology). POLYM. ENG. SCI., 2008. © 2007 Society of Plastics Engineers [source] Expression of Notch signalling-related genes in normal and differentiating rat dental pulp cellsAUSTRALIAN ENDODONTIC JOURNAL, Issue 2 2010Hantang Sun dds Abstract Notch signalling is of fundamental importance to various processes during embryonic development and in adults. The possible role of Hey1, an important Notch signalling component, in odontoblast differentiation was evaluated in this study. Primary cultured dental pulp cells, derived from upper incisors of 5-week-old Wistar rats, were placed in ,-modification of Eagle's minimal essential medium supplemented with 10% Fetal Bovine Serum (FBS), and ascorbic acid (AA) and ,-glycerophosphate (,-GP), with or without dexamethasone, and cultured on dishes coated with collagen type IA for 7 days. Conventional and real-time Polymerase Chain Reaction (PCR) was performed to determine the expression of Notch-related genes and dentin sialophosphoprotein as a marker of odontoblast differentiation. Dentin sialophosphoprotein and Hey1 expression was significantly increased and decreased in the presence of AA + ,-GP compared with controls, respectively. These findings suggest that Hey1 may be a negative regulator in odontoblast differentiation. [source] Survival rate of preantral follicles derived from vitrified neonate mouse ovarian tissue by cryotop and conventional methodsBIOFACTORS, Issue 2 2007H. Eimani Abstract The aim of this study was to investigate the growth and survival rate of preantral follicles isolated from vitrified ovarian tissue by Cryotop and conventional methods. The ovaries of 14-day-old mice were separated and divided into four groups as following: Cryotop group, vitrified by Cryotop; CV (Conventional; CV) group, vitrified by conventional straw; toxicity test group and control group. After warming the vitrified ovaries, isolated preantral follicles from four groups were cultured for 4 days to compare survival rate and follicular growth between above-mentioned groups. Survival rate (97.3%) in toxicity test group alike the control group (98.7%) were significantly higher (P < 0.05) than the Cryotop (92.7%) and CV (47.7%) groups. Increase in follicle diameters after 4 days in Cryotop and CV groups was significantly lower (P < 0.05) than the control and toxicity test groups, but growth and survival rate of follicles in Cryotop group was significantly higher (P < 0.05) than the CV group. These results demonstrated that ovarian tissue vitrification by Cryotop highly preserves the viability rate of preantral follicles. [source] Conventional and alternative methods for providing analgesia in renal colicBJU INTERNATIONAL, Issue 3 2005Kim Davenport First page of article [source] ChemInform Abstract: Conventional and Microwave Induced Synthesis of Various Azetidinone (III) and Thiazolidinone Derivatives (V) from 3-[(1E)-1-Aza-2-(2-chloro-7-methoxy-3-quinolyl)-vinyl] -4-(aryldiazenyl)phenol (I) and Their Antimicrobial Screening.CHEMINFORM, Issue 9 2009Jigisha A. Patel Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Oxidation of Alcohols with 1-Decyl-4-aza-1-azoniabicyclo[2.2.2]-octane Chlorochromate under Conventional and Solvent-Free Conditions.CHEMINFORM, Issue 49 2006A. R. Hajipour Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] | ||||||||||||||||||||||||||||||||||||||||||||||