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Relative Increase (relative + increase)
Selected AbstractsRelative increase in choline in the occipital cortex in chronic fatigue syndromeACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2002B. K. Puri Puri BK, Counsell SJ, Zaman R, Main J, Collins AG, Hajnal JV, Davey NJ. Relative increase in choline in the occipital cortex in chronic fatigue syndrome. Acta Psychiatr Scand 2002: 106: 224,226. © Blackwell Munksgaard 2002. Objective:,To test the hypothesis that chronic fatigue syndrome (CFS) is associated with altered cerebral metabolites in the frontal and occipital cortices. Method:,Cerebral proton magnetic resonance spectroscopy (1H MRS) was carried out in eight CFS patients and eight age- and sex-matched healthy control subjects. Spectra were obtained from 20 × 20 × 20 mm3 voxels in the dominant motor and occipital cortices using a point-resolved spectroscopy pulse sequence. Results:,The mean ratio of choline (Cho) to creatine (Cr) in the occipital cortex in CFS (0.97) was significantly higher than in the controls (0.76; P=0.008). No other metabolite ratios were significantly different between the two groups in either the frontal or occipital cortex. In addition, there was a loss of the normal spatial variation of Cho in CFS. Conclusion:,Our results suggest that there may be an abnormality of phospholipid metabolism in the brain in CFS. [source] Measurement of barbed ends, actin polymerization, and motility in live carcinoma cells after growth factor stimulation,CYTOSKELETON, Issue 4 2004Mike Lorenz Abstract Motility is associated with the ability to extend F-actin-rich protrusions and depends on free barbed ends as new actin polymerization sites. To understand the function and regulation of different proteins involved in the process of generating barbed ends, e.g., cofilin and Arp2/3, fixed cell approaches have been used to determine the relative barbed end concentration in cells. The major disadvantages of these approaches are permeabilization and fixation of cells. In this work, we describe a new live-cell time-lapse microscopy assay to determine the increase of barbed ends after cell stimulation that does not use permeabilization and provides a better time resolution. We established a metastatic carcinoma cell line (MTLn3) stably expressing GFP-,-actin at physiological levels. Stimulation of MTLn3 cells with epidermal growth factor (EGF) causes rapid and transient lamellipod protrusion along with an increase in actin polymerization at the leading edge, which can be followed in live cell experiments. By measuring the increase of F-actin at the leading edge vs. time, we were able to determine the relative increase of barbed ends after stimulation with a high temporal resolution. The F-actin as well as the barbed end concentration agrees well with published data for this cell line. Using this newly developed assay, a decrease in lamellipod extension and a large reduction of barbed ends was documented after microinjecting an anti-cofilin function blocking antibody. This assay has a high potential for applications where rapid changes in the dynamic filament population are to be measured. Cell Motil. Cytoskeleton 57:207,217, 2004. © 2004 Wiley-Liss, Inc. [source] Cardiac natriuretic peptides and continuously monitored atrial pressures during chronic rapid pacing in pigsACTA PHYSIOLOGICA, Issue 2 2000Changes in atrial natriuretic peptide (ANP), N-terminal proatrial natriuretic peptide and brain natriuretic peptide (BNP) were evaluated in relation to continuously monitored atrial pressures in a pacing model of heart failure. Pigs were subjected to rapid atrial pacing (225 beats min,1) for 3 weeks with adjustments of pacing frequencies if the pigs showed overt signs of cardiac decompensation. Atrial pressures were monitored by a telemetry system with the animals unsedated and freely moving. Left atrial pressure responded stronger and more rapidly to the initiation of pacing and to alterations in the rate of pacing than right atrial pressure. Plasma natriuretic peptide levels were measured by radioimmunoassay and all increased during pacing with BNP exhibiting the largest relative increase (2.9-fold increase relative to sham pigs). Multiple regression analysis with dummy variables was used to evaluate the relative changes in natriuretic peptides and atrial pressures and the strongest correlation was found between BNP and left atrial pressure with R,2=0.81. Termination of pacing resulted in rapid normalization of ANP values in spite of persistent elevations in atrial pressures. This may reflect an increased metabolism or an attenuated secretory response of ANP to atrial stretch with established heart failure. In conclusion, 3 weeks of rapid pacing induced significant increases in atrial pressures and natriuretic peptide levels. All the natriuretic peptides correlated with atrial pressures with BNP appearing as a more sensitive marker of cardiac filling pressures than ANP and N-terminal proatrial natriuretic peptide. [source] Direct and indirect time spent on care of dental trauma: a 2-year prospective study of children and adolescentsDENTAL TRAUMATOLOGY, Issue 1 2000U. Glendor Abstract , The aim was to account for the total time spent by professional care-givers (direct time) and by patients and companions engaged as support and help (indirect time) to treat and otherwise attend to children and adolescents with dental trauma to primary and permanent teeth. The study was based on a random sample of 192 children and adolescents with dental traumas reported to an insurance company and prospectively followed up by telephone interviews over a period of 2 years after the trauma episode. On average, direct time represented 16% of total time for all visits for dental trauma to permanent teeth and 11% for trauma to primary teeth. The most extensive type of indirect time was transport time, which took up 30% of the total time spent on injuries to permanent teeth and 36% for injuries to primary teeth. Multiple regression analysis of the impact of dental and demographic injury variables on the time variables showed that complicated trauma was associated with extended time, direct as well as indirect, for permanent and primary teeth injuries. Our estimate of the average relative increase in total time spent by patients and companions in cases of complicated injury to permanent teeth was 117% (95% confidence interval [CI], 52,211) for patients and 112% (95% CI, 42,217) for companions. For transport time a strong predictor was access to a dental clinic near the place of residence. Lack of access could extend the average transport time by 180% (95% CI, 80,335) for patients and 163% (95% CI, 67,317) for their companions in cases of injuries to primary teeth. [source] Linear and nonlinear measures of blood pressure variability: Increased chaos of blood pressure time series in patients with panic disorderDEPRESSION AND ANXIETY, Issue 2 2004Vikram K. Yeragani M.B.B.S. Abstract Arterial blood pressure (BP) variability increases progressively with the development of hypertension and an increase in BP variability is associated with end organ damage and cardiovascular morbidity. On the other hand, a decrease in heart rate (HR) variability is associated with significant cardiovascular mortality. There is a strong association between cardiovascular mortality and anxiety. Several previous studies have shown decreased HR variability in patients with anxiety. In this study, we investigated beat-to-beat variability of systolic and diastolic BP (SBP and DBP) in normal controls and patients with panic disorder during normal breathing and controlled breathing at 12, and 20 breaths per minute using linear as well as nonlinear techniques. Finger BP signal was obtained noninvasively using Finapres. Standing SBPvi and DBP BPvi (log value of BP variance corrected for mean BP divided by HR variance corrected for mean HR) were significantly higher in patients compared to controls. Largest Lyapunov exponent (LLE) of SBP and DBP, a measure of chaos, was significantly higher in patients in supine as well as standing postures. The ratios of LLE (SBP/HR) and LLE (DBP/HR) were also significantly higher (P < .001) in patients compared to controls. These findings further suggest dissociation between HR and BP variability and a possible relative increase in sympathetic function in anxiety. This increase in BP variability may partly explain the increase in cardiovascular mortality in this group of patients. Depression and Anxiety 19:85-95, 2004. © 2004 Wiley-Liss, Inc. [source] Heart rate and QT variability in children with anxiety disorders: A preliminary reportDEPRESSION AND ANXIETY, Issue 2 2001Vikram K. Yeragani M.B.B.S. Abstract This study compared beat-to-beat heart rate and QT variability in children with anxiety disorders (n=7) and normal controls (n=15) by using an automated algorithm to compute QT intervals. An increase in QT variability appears to be associated with a higher risk for sudden cardiac death. A decrease in heart rate variability is also linked to significant cardiovascular events. Supine detrended QT variability, QT variability corrected for mean QT interval, and QTvi (a log ratio of QT variance normalized for mean QT over heart rate variability normalized for mean heart rate) were significantly higher in children with anxiety compared to controls (P<0.05). The largest Lyapunov Exponent (LLE) of heart rate time series was significantly lower (P<0.05) in children with anxiety compared to controls. These findings suggest a relative increase in sympathetic activity and a relative decrease in cardiac vagal activity in children with anxiety disorders, and are discussed in the context of the effects of tricyclics on cardiac autonomic function in children, and the rare occurrence of sudden death during tricyclic antidepressant treatment. Depression and Anxiety 13:72,77, 2001. © 2001 Wiley-Liss, Inc. [source] Orthopaedic issues in the musculoskeletal care of adults with cerebral palsyDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2009HELEN M HORSTMANN MD Aims, Orthopaedic care of adults with cerebral palsy (CP) has not been well documented in orthopaedic literature. This paper focuses on some of the common problems which present themselves when adults with CP seek orthopaedic intervention. In particular, we review the most common orthopaedic issues which present to the Penn Neuro-Orthopaedics Program. Method, A formal review of consecutive surgeries performed by the senior author on adults with CP was previously conducted. This paper focuses on the health delivery care for the adult with orthopaedic problems related to cerebral palsy. Ninety-two percent of these patients required lower extremity surgery. Forty percent had procedures performed on the upper extremities. Results, The majority of problems seen in the Penn Neuro-Orthopaedics Program are associated with the residuals of childhood issues, particularly deformities associated with contractures. Patients are also referred for treatment of acquired musculoskeletal problems such as degenerative arthritis of the hip or knee. A combination of problems contribute most frequently to foot deformities and pain with weight-bearing, shoewear or both, most often due to equinovarus. The surgical correction of this is most often facilitated through a split anterior tibial tendon transfer. Posterior tibial transfers are rarely indicated. Residual equinus deformities contribute to a pes planus deformity. The split anterior tibial tendon transfer is usually combined with gastrocnemius-soleus recession and plantar release. Transfer of the flexor digitorum longus to the os calcis is done to augment the plantar flexor power. Rigid pes planus deformity is treated with a triple arthrodesis. Resolution of deformity allows for a good base for standing, improved ability to tolerate shoewear, and/or braces. Other recurrent or unresolved issues involve hip and knee contractures. Issues of lever arm dysfunction create problems with mechanical inefficiency. Upper extremity intervention is principally to correct contractures. Internal rotation and adductor tightness at the shoulder makes for difficult underarm hygiene and predispose a patient to a spiral fracture of the humerus. A tight flexor, pronation pattern is frequently noted through the elbow and forearm with further flexion contractures through the wrist and fingers. Lengthenings are more frequently performed than tendon transfers in the upper extremity. Arthrodesis of the wrist or on rare occasions of the metacarpal-phalangeal joints supplement the lengthenings when needed. Conclusions, The Penn Neuro-Orthopaedics Program has successfully treated adults with both residual and acquired musculoskeletal deformities. These deformities become more critical when combined with degenerative changes, a relative increase in body mass, fatigue, and weakness associated with the aging process. [source] Effect of residual vanadyl ions on the spectroscopic analysis of humic acids: a multivariate approachEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 3 2008E. H. Novotny Summary In a study of the vanadyl (VO2+)-humic acids system, the residual vanadyl ion suppressed fluorescence and specific electron paramagnetic resonance (EPR) and NMR signals. In the case of NMR, the proton rotating frame relaxation times (T1,H) indicate that this suppression is due to an inefficient H-C cross polarization, which is a consequence of a shortening of T1,H. Principal components analysis (PCA) facilitated the isolation of the effect of the VO2+ ion and indicated that the organic free radical signal was due to at least two paramagnetic centres and that the VO2+ ion preferentially suppressed the species whose electronic density is delocalized over O atoms (greater g -factor). Additionally, the newly obtained variables (principal components , PC) indicated that, as the result of the more intense tillage a relative increase occurred in the accumulation of: (i) recalcitrant structures; (ii) lignin and long-chain alkyl structures; and (iii) organic free radicals with smaller g -factors. [source] Supernatants of Pseudomonas aeruginosa induce the Pseudomonas -specific antibiotic elafin in human keratinocytesEXPERIMENTAL DERMATOLOGY, Issue 4 2003Ulf Meyer-Hoffert Abstract: Elafin is a skin-derived serine-protease inhibitor. It is thought to be important to prevent human leukocyte elastase-mediated tissue damage and might play an important role in maintaining the integrity of the human epidermis. Recent studies have provided evidence for an antimicrobial activity of elafin against P. aeruginosa. As gram-negative infections typically occur in barrier-disrupted skin we were interested to determine whether supernatants of the gram-negative bacteria P. aeruginosa and Escherichia coli were capable of inducing elafin expression. Supernatants of various P. aeruginosa strains stimulated elafin mRNA-expression and protein release, whereas supernatants of E. coli did not induce elafin expression. In non-differentiated cells the relative increase of elafin mRNA was much higher (100-fold) than in differentiated cells (sixfold), although the latter exhibited higher constitutive mRNA-expression (150-fold). However, concentrations of secreted elafin were similar in differentiated and non-differentiated cells after stimulation. We could not confirm a bactericidal effect against P. aeruginosa as described previously but observed that its growth was inhibited as demonstrated for different strains in liquid cultures. Growth of E. coli was not affected by elafin. In conclusion, the data presented in this paper suggest that elafin represents an innate immune response factor induced by secreted products of P. aeruginosa. Besides its elastase inhibitory potency elafin is an antimicrobial agent against P. aeruginosa. [source] DNA vaccines against chronic lung infections by Pseudomonas aeruginosaFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2-3 2003J Staczek Abstract Vaccines containing outer membrane protein F (OprF) of Pseudomonas aeruginosa are effective in reducing lesion severity in a mouse pulmonary chronic infection model. One OprF-based vaccine, called F/I, contains carboxy oprF sequences fused to oprI in an expression vector. When delivered three times biolistically by gene gun, the F/I vaccine induces protection that is antibody-mediated in outbred mice. To demonstrate the role of F/I -induced antibody-mediated immunity, B-cell-deficient [B(,)] and B-cell-intact [B(+)] mice were immunized with F/I, challenged with Pseudomonas, and examined for lesion severity. As expected, F/I -immunized B(+) mice had fewer and less severe lesions than vector-immunized B(+) mice. However, surprisingly, F/I - and vector-immunized B(,) mice were equally protected to levels similar to F/I -immunized B(+) mice. Examination of immune cell populations and cytokine levels indicated a relative increase in the quantity of CD3+ T-lymphocytes in vector- or F/I -immunized and challenged B(,) mice compared to B(+) mice. These data indicate the protective role played by cell-mediated immunity in B(,) mice, which supports our hypothesis that cell-mediated immunity can play an important role in protection against P. aeruginosa. [source] Above- and below-ground responses of C3,C4 species mixtures to elevated CO2 and soil water availabilityGLOBAL CHANGE BIOLOGY, Issue 3 2003JUSTIN D. DERNER Abstract We evaluated the influences of CO2[Control, , 370 µmol mol,1; 200 µmol mol,1 above ambient applied by free-air CO2 enrichment (FACE)] and soil water (Wet, Dry) on above- and below-ground responses of C3 (cotton, Gossypium hirsutum) and C4 (sorghum, Sorghum bicolor) plants in monocultures and two density mixtures. In monocultures, CO2 enrichment increased height, leaf area, above-ground biomass and reproductive output of cotton, but not sorghum, and was independent of soil water treatment. In mixtures, cotton, but not sorghum, above-ground biomass and height were generally reduced compared to monocultures, across both CO2 and soil water treatments. Density did not affect individual plant responses of either cotton or sorghum across the other treatments. Total (cotton + sorghum) leaf area and above-ground biomass in low-density mixtures were similar between CO2 treatments, but increased by 17,21% with FACE in high-density mixtures, due to a 121% enhancement of cotton leaf area and a 276% increase in biomass under the FACE treatment. Total root biomass in the upper 1.2 m of the soil was not influenced by CO2 or by soil water in monoculture or mixtures; however, under dry conditions we observed significantly more roots at lower soil depths (> 45 cm). Sorghum roots comprised 81,85% of the total roots in the low-density mixture and 58,73% in the high-density mixture. CO2 -enrichment partly offset negative effects of interspecific competition on cotton in both low- and high-density mixtures by increasing above-ground biomass, with a greater relative increase in the high-density mixture. As a consequence, CO2 -enrichment increased total above-ground yield of the mixture at high density. Individual plant responses to CO2 enrichment in global change models that evaluate mixed plant communities should be adjusted to incorporate feedbacks for interspecific competition. Future field studies in natural ecosystems should address the role that a CO2 -mediated increase in C3 growth may have on subsequent vegetation change. [source] An inhibitor of cyclin-dependent kinase, stress-induced p21Waf-1/Cip-1, mediates hepatocyte mito-inhibition during the evolution of cirrhosis,HEPATOLOGY, Issue 6 2005John G. Lunz III During the evolution of cirrhosis, there is a relative decrease in volume percentage of hepatocytes and a relative increase in biliary epithelial cells and myofibroblasts. This is recognized histopathologically as a ductular reaction and leads to gradual distortion of the normal hepatic architecture. The final or decompensated stage of cirrhosis is characterized by a further decline in hepatocyte proliferation and loss of functional liver mass that manifests clinically as ascites, encephalopathy, and other signs of liver failure. In this report, we tested the hypothesis that p21-mediated hepatocyte mito-inhibition accelerates the evolution of cirrhosis using an established mouse model of decompensated biliary cirrhosis, p21-deficient mice, and liver tissue from humans awaiting liver replacement. Despite the same insult of long-term (12-week) bile duct ligation, mice prone to decompensation showed significantly more oxidative stress and hepatocyte nuclear p21 expression, which resulted in less hepatocyte proliferation, an exaggerated ductular reaction, and more advanced disease compared with compensation-prone controls. Mice deficient in p21 were better able than wild-type controls to compensate for long-term bile duct ligation because of significantly greater hepatocyte proliferation, which led to a larger liver mass and less architectural distortion. Mito-inhibitory hepatocyte nuclear p21 expression in humans awaiting liver replacement directly correlated with pathological disease stage and model of end-stage liver disease scoring. In conclusion, stress-induced upregulation of hepatocyte p21 inhibits hepatocyte proliferation during the evolution of cirrhosis. These findings have implications for understanding the evolution of cirrhosis and associated carcinogenesis. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html). (HEPATOLOGY 2005.) [source] Rising hospitalization rates for inflammatory bowel disease in the United States between 1998 and 2004,INFLAMMATORY BOWEL DISEASES, Issue 12 2007Geoffrey C. Nguyen MD Abstract Background: Recent epidemiological studies suggest that the prevalences of Crohn's disease (CD) and ulcerative colitis (UC) are increasing in the United States. We sought to determine whether nationwide rates of inflammatory bowel disease (IBD) hospitalizations have increased in response to temporal trends in prevalence. Methods: We identified all admissions with a primary diagnosis of CD or UC, or 1 of their complications in the Nationwide Inpatient Sample between 1998 and 2004. National estimates of hospitalization rates and rates of surgery were determined using the U.S. Census population as the denominator. Results: There were an estimated 359,124 and 214,498 admissions for CD and UC, respectively. The overall hospitalization rate for CD was 18.0 per 100,000 and that for UC was 10.8 per 100,000. There was a 4.3% annual relative increase in hospitalization rate for CD (P < 0.0001) and a 3.0% annual increase for UC (P < 0.0001). Surgery rates were 3.4 bowel resections per 100,000 for CD and 1.2 colectomies per 100,000 for UC and remained stable. There were no temporal patterns for average length of stay for CD (5.8 days) or for UC (6.8 days). The national estimate of total inpatient charges attributable to CD increased from $762 million to $1,330 million between 1998 and 2004, and that for UC increased from $592 million to $945 million. Conclusions: Hospitalization rates for IBD, particularly CD, have increased within a 7-year period, incurring a substantial rise in inflation-adjusted economic burden. The findings reinforce the need for effective treatment strategies to reduce IBD complications. (Inflamm Bowel Dis 2007) [source] Time-of-flight secondary ion mass spectrometry analysis of the application of a cationic conditioner to ,clean' hairINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 5 2004A. Harvey In this study the applicability of the surface-sensitive Time-of-flight secondary ion mass spectrometry (ToF-SIMS) technique to hair analysis and associated aqueous processing is evaluated. ToF-SIMS analysis of ,as received' human hair indicates the presence of silicones, anionic surfactants, and cationic conditioners, from previous treatments, on the fiber surface. Cleaning of the hair with SLS or SLES results in adsorption of the surfactants onto the fiber surface. In particular, the more non-polar surfactant components have greater substantivity for the fiber surface, as indicated by the relative increase in their ToF-SIMS intensity. Application of the Incroquat Behenyl 18-MEA conditioner to both ,virgin' and bleached hair results in the adsorption of the cationic C18, C20, C22, and C21 surfactant components onto the hair surface. The ToF-SIMS data indicate higher levels of conditioner on the bleached hair relative to the undamaged hair. [source] Closed-loop identification of the time-varying dynamics of variable-speed wind turbinesINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 1 2009J. W. van Wingerden Abstract The trend with offshore wind turbines is to increase the rotor diameter as much as possible to decrease the costs per kWh. The increasing dimensions have led to the relative increase in the loads on the wind turbine structure. Because of the increasing rotor size and the spatial load variations along the blade, it is necessary to react to turbulence in a more detailed way: each blade separately and at several separate radial distances. This combined with the strong nonlinear behavior of wind turbines motivates the need for accurate linear parameter-varying (LPV) models for which advanced control synthesis techniques exist within the robust control framework. In this paper we present a closed-loop LPV identification algorithm that uses dedicated scheduling sequences to identify the rotational dynamics of a wind turbine. We assume that the system undergoes the same time variation several times, which makes it possible to use time-invariant identification methods as the input and the output data are chosen from the same point in the variation of the system. We use time-invariant techniques to identify a number of extended observability matrices and state sequences that are inherent to subspace identification identified in a different state basis. We show that by formulating an intersection problem all states can be reconstructed in a general state basis from which the system matrices can be estimated. The novel algorithm is applied on a wind turbine model operating in closed loop. Copyright © 2008 John Wiley & Sons, Ltd. [source] Gill morphometrics in relation to gas transfer and ram ventilation in high-energy demand teleosts: Scombrids and billfishesJOURNAL OF MORPHOLOGY, Issue 1 2010Nicholas C. Wegner Abstract This comparative study of the gill morphometrics in scombrids (tunas, bonitos, and mackerels) and billfishes (marlins, swordfish) examines features of gill design related to high rates of gas transfer and the high-pressure branchial flow associated with fast, continuous swimming. Tunas have the largest relative gill surface areas of any fish group, and although the gill areas of non-tuna scombrids and billfishes are smaller than those of tunas, they are also disproportionally larger than those of most other teleosts. The morphometric features contributing to the large gill surface areas of these high-energy demand teleosts include: 1) a relative increase in the number and length of gill filaments that have, 2) a high lamellar frequency (i.e., the number of lamellae per length of filament), and 3) lamellae that are long and low in profile (height), which allows a greater number of filaments to be tightly packed into the branchial cavity. Augmentation of gill area through these morphometric changes represents a departure from the general mechanism of area enhancement utilized by most teleosts, which lengthen filaments and increase the size of the lamellae. The gill design of scombrids and billfishes reflects the combined requirements for ram ventilation and elevated energetic demands. The high lamellar frequencies and long lamellae increase branchial resistance to water flow which slows and streamlines the ram ventilatory stream. In general, scombrid and billfish gill surface areas correlate with metabolic requirements and this character may serve to predict the energetic demands of fish species for which direct measurement is not possible. The branching of the gill filaments documented for the swordfish in this study appears to increase its gill surface area above that of other billfishes and may allow it to penetrate oxygen-poor waters at depth. J. Morphol. 2010. © 2009 Wiley-Liss, Inc. [source] Comparison of Smoking, Drinking, and Marijuana Use Between Students Present or Absent on the Day of a School-Based SurveyJOURNAL OF SCHOOL HEALTH, Issue 4 2006Pascal Bovet The study population was a representative sample of all students of secondary schools in the Seychelles (Indian Ocean). Students absent on the day of the survey were traced and requested to complete the same self-administered questionnaire as did present students. Self-reported consumption of cigarettes, alcohol, and marijuana were measured. Of the sample of 1453 eligible students aged 11 to 17 years, 1321 "present students" completed the survey (90.9% participation), 11 refused to answer all questions, and 121 were not present at school. We could trace 105 of the 121 students not present at school on the survey day ("absent students"), and all of them completed the questionnaire over the next 4 weeks. The prevalence of risk behaviors was significantly higher in absent than present students for current smoking and drinking. Inclusion of data from the absent students resulted in a relative increase in the prevalence of the considered behaviors by 3% to 8% as compared to data based on present students only. In conclusion, the prevalence of risk behaviors was higher in absent than present students. Adjusting for data of absent students increased the prevalence estimates in the base population. (J Sch Health. 2006;76(4):133-137) [source] MYELINATION DEFICIT IN NERVE OF SUCKLING RATS DUE TO CYCLOLEUCINE -INDUCED DEFICIENCY OF METHYL DONORSJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2000R. Bianchi We used cycloleucine (CL) , which prevents methionine conversion to S-adenosyl-methionine (SAMe) by inhibiting ATP-L-methionine-adenosyl-transferase (MAT) , to characterize the lipid and protein changes induced by methyl donors deficit in peripheral nerve and brain myelin in rats during development. We have previously shown that CL (400 mg/kg ip) given to suckling rats at days 7, 8, 12, and 13 after birth reduced brain and sciatic nerve weight gain, brain myelin content, protein, phospholipid (PL), and galactolipid concentration in comparison to control. Among PLs, only sphingomyelin (SPH) significantly increased by 35,50%. SAMe p-toluensulphonate (SAMe-SD4) (100 mg/kg, ip) given daily from day 7, as with exogenous SAMe, partially prevented some lipid alterations induced by CL, particularly galactolipid and SPH. To test the ability of CL to affect PL metabolism we have measured de novo PL biosynthesis, ex vivo in nerve homogenates (in comparison with brain homogenates) from control and CL-treated animals killed at day 18 after birth, starting from labelled substrates ([3H]-choline, specific activity 20 mCi/mmol) in a Tris/HCl buffer, containing 5 mM MgCl2, 0.2 mM EDTA, 0.1 mM ATP, and 0.5 mM of the labelled substrates. After 60 min incubation, lipids were extracted, PL separated by TLC, and corresponding silica gel fractions scraped and counted in a liquid scintillator. Phosphatidylcholine enrichment in labelled choline resulted in slight increases in brain and sciatic nerve of CL-treated rats, suggesting an increased synthesis rate via the Kennedy pathway, possibly due to the reduced availability of methyl donors. Interestingly, choline incorporation into SPH in brain and nerve myelin resulted in significant increases of 30,40%. In agreement with the observed decrease of galactolipid content and the relative increase in SPH, these data suggest an alteration in sphingolipid metabolism after CL. Among proteins, in sciatic nerves of CL-treated pups the relative content of a number of polypeptides, namely the 116, 90, 66, 58, and 56 kDa bands, decreased, whereas others increased; the most abundant PNS protein, protein zero, remained unchanged. The analyses of myelin basic protein isoforms revealed a dramatic increase in the 14.0 and 18.5 forms, indicating early active myelination. SAMe-SD4 treatment counteracted, and in some cases normalized, these changes. In summary, methyl donor deficiency induced by MAT inhibition produces myelin lipid and protein alterations, partly counteracted by SAMe-SD4 administration. The financial support of Telethon-Italy (grant No. D 51) is gratefully acknowledged. [source] Influence of Starvation on Flesh Quality of Farmed Dentex, Dentex dentexJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2010María Dolores Suárez Dentex (mean initial weight 324 ± 5 g) from a fish farm were divided into two groups (control and fasted). At the end of experimental period (5 wk), dentex were sampled for gross muscle composition and quality analysis. For post mortem muscle analysis, after death, fish were kept in a cold chamber at 4 C, and muscle samples were taken at 4 (prerigor state), 24 (rigor state), and 82 (postrigor state) h after slaughtering. In each fish, textural and biochemical parameters were determined. During starvation, there was a drastic reduction in muscle lipid content and a relative increase of the proteolysis. There were little qualitative changes in the fatty-acid profile of muscle lipids, although a significant increase in n3/n6 ratio in the starved dentex was detected. Starved fish also showed higher muscle firmness, but no differences in pH and water holding capacity were observed. Total and myofibrillar protein and collagen content increased significantly in starved dentex. Firmness during post mortem storage was significantly higher in starved fish, compared with control group. Preslaughtering feeding status showed decisive influence on the evolution dentex muscle quality parameters during cold storage. [source] Contribution of indirect computed tomographic venography to the diagnosis of postpartum venous thromboembolismJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 9 2008M. P. REVEL Summary.,Background:,The diagnostic value of indirect computed tomographic venography (CTV), following thoracic computed tomographic angiography (CTA), has not been specifically evaluated in postpartum patients with suspected pulmonary embolism. Objectives: To assess the diagnostic value of CTV in postpartum venous thromboembolism. Methods: We reviewed all CTA and CTV procedures performed during the last 7 years in our institution for suspected pulmonary embolism during the postpartum period. We focused on the quality of CTA, the rates of positive CTA and isolated positive CTV findings, and alternative diagnoses provided by CTV. Results: Fifty-five CTA and 33 CTV procedures were performed for suspected pulmonary embolism in 47 patients referred between 24 h and 2 months after Cesarean (34 patients) or vaginal (13 patients) delivery. Of the 33 patients who had both CTA and CTV, seven had positive CTA findings and four had isolated positive CTV findings. Thus, the absolute increase in the venous thromboembolism detection rate following CTV was 12.1% [95% confidence interval (CI) 4.0,29.1]. Subcapsular hematoma of the liver or spleen was found on CTV in another two patients without venous thromboembolism. Consequently, CTV had a direct impact on clinical management in six of 33 patients (18%). Conclusion: Our results suggest that postpartum patients with suspected pulmonary embolism have a significant rate of pelvic vein thrombosis and that the use of CTV leads to a 31% relative increase in the detection rate of venous thromboembolism as compared to CTA alone in these patients. [source] Increasing sales by introducing non-salable itemsMANAGERIAL AND DECISION ECONOMICS, Issue 8 2006Kobi Kriesler Rationality implies that adding ,irrelevant' and, in particular, inferior alternatives to the opportunity set cannot increase the choice probability of some other alternative. In this study, we propose a novel approach that can rationalize an intended addition of such alternatives because it strictly increases the choice probability of some existing alternative. The driving force behind the existence and extent of such an increase is the random nature of individual preferences, that implies intransitivity, and the random nature of the applied choice procedures. We study the case of a firm interested in increasing the sales of some of its existing products by introducing a new and inferior (non-salable) product. Our main results focus on the feasibility and potential advantage of a successful such strategy. We first establish necessary and sufficient conditions for an increase in the sale probability and then derive the maximal possible absolute and relative increase in this probability, when the firm has extremely limited information on the characteristics of the consumers. We then derive analogous results, assuming that the existing line of products consists of just two items and that the firm has accurate information on the consumers' stochastic preferences over the existing products. These later results are illustrated using some experimental evidence. The applicability of the approach is finally briefly discussed in the context of branding policy. Copyright © 2006 John Wiley & Sons, Ltd. [source] THE REAL EXCHANGE RATE AND THE BALASSA,SAMUELSON EFFECT: THE ROLE OF THE DISTRIBUTION SECTORPACIFIC ECONOMIC REVIEW, Issue 1 2005Ronald MacDonald The main result is that an increase in the productivity and product market competition of the distribution sector with respect to foreign countries leads to an appreciation of the real exchange rate, similar to what a relative increase in the domestic productivity of tradables does. This contrasts with the result that one would expect by considering the distribution sector as belonging to the non-tradable sector. One explanation may lie in the use of the services from the distribution sector in the tradable sector. [source] Seasonal variation of the lipoidal matters and hypolipidaemic activity of the red alga Corallina officinalis L.PHYTOTHERAPY RESEARCH, Issue 1 2003N. E. Awad Abstract The lipoidal matters of Corallina officinalis L. showed a seasonal nonsignificant quantitative variation. However, the fatty acids revealed a relative increase in the summer and winter, while unsaponifiable matter exhibited a slight increase in the spring. The GC/MS analysis of saponifiable and unsaponifiable matter of the algal samples collected in different seasons revealed that samples collected in the spring contained a low cholesterol content and high steroidal compounds as well as high polyunsaturated fatty acids. The alcohol extract, hexane extract and fatty acid fraction of this algal sample exhibited a significant hypolipidaemic activity. Also, two biologically active fractions of hydrocarbons were isolated by CC technique from the hexane fraction of C. officinalis L. and identified by GC/MS. Copyright © 2003 John Wiley & Sons, Ltd. [source] Antioxidant and Pigment Composition during Autumnal Leaf Senescence in Woody Deciduous Species Differing in their Ecological TraitsPLANT BIOLOGY, Issue 5 2003J. I. García-Plazaola Abstract: Photoprotection mechanisms have been studied during autumnal senescence in sun and shade leaves of woody plants with different ecological characteristics and senescence patterns. Three of them belonging to the same family, Betulaceae: the shade-intolerant and early successional species (Betula alba L.), the shade-tolerant and late successional species (Corylus avellana L.), and an N-fixing tree with low N resorption efficiency (Alnus glutinosa L.). The other two species: a shade-intolerant (Populus tremula L.) and a shade-tolerant (Cornus sanguinea L.), were chosen because of their ability to accumulate anthocyanins during autumnal leaf senescence. The study of plants with different ecological strategies allowed us to establish general trends in photoprotection mechanisms during autumnal senescence, when nutrient remobilisation occurs, but also during whole leaf ontogeny. We have not found a clear relationship between shade tolerance and the level of photoprotection; the main difference between both groups of species being the presence of ,-carotene in shade leaves of shade-tolerant species. Preceding autumn, nitrogen resorption started in mid-summer and occurred in parallel with a slight and continuous ascorbate, chlorophyll and carotenoid degradation. However, the ascorbate pool remained highly reduced and lipid oxidation did not increase at this time. Contrasting with ascorbate, ,-tocopherol accumulated progressively in all species. Only during the last stages of senescence was chlorophyll preferentially degraded with respect to carotenoids, leading to the yellowing of leaves, except in A. glutinosa in which a large retention of chlorophyll and N took place. Senescing leaves were characterised, except in C. sanguinea, by a relative increase in the proportion of de-epoxidised xanthophylls: zeaxanthin, antheraxanthin and lutein. The light-induced accumulation of anthocyanins in C. sanguinea could play an additional protective role, compensating for the low retention of de-epoxidised xanthophylls. These different strategies among deciduous species are consistent with a role for photoprotective compounds in enhancing nitrogen remobilization and storage for the next growing season. [source] Overcoming the poor short wavelength spectral response of CdS/CdTe photovoltaic modules via luminescence down-shifting: ray-tracing simulationsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 1 2007B.S. Richards Abstract The short-wavelength response of cadmium sulfide/cadmium telluride (CdS/CdTe) photovoltaic (PV) modules can be improved by the application of a luminescent down-shifting (LDS) layer to the PV module. The LDS layer contains a mixture of fluorescent organic dyes that are able to absorb short-wavelength light of ,,<,540,nm, for which the PV module exhibited low external quantum efficiency (EQE), and re-emit it at a longer wavelength (,,>,540,nm), where the solar cell EQE is high. Ray-tracing simulations indicate that a mixed LDS layer containing three dyes could lead to an increase in the short-circuit current density from Jsc,=,19.8,mA/cm2 to Jsc,=,22.9,mA/cm2 for a CdS/CdTe PV module. This corresponds to an increase in conversion efficiency from 9.6% to 11.2%. This indicates that a relative increase in the performance of a production CdS/CdTe PV module of nearly 17% can be expected via the application of LDS layers, possibly without any making any alterations to the solar cell itself. Copyright © 2006 John Wiley & Sons, Ltd. [source] Cell Subpopulation-related Volumetric Parameters: a Complementary Tool of the Modified Hypo-osmotic Swelling Test on Model of Boar SpermatozoaREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2000A. Petrounkina Content It is a general property of the intact animal cell to swell rapidly in response to hypo-osmotic conditions. The modified hypo-osmotic swelling test (HOS-test) is an indicative test to evaluate the integrity of the plasma membrane by means of an electronic cell counter, based on the relative increase of the cell volume in response to hypo-osmotic conditions. In this study the relationships between the osmotically induced changes of the cell volume of boar spermatozoa as determined by cell counter and the integrity of the membrane as determined by propidium iodide staining (PI) were studied. Boar sperm cell volume distributions were measured under iso-osmotic (300 mosmolar) conditions and after a hypo-osmotic stress (150 mosmolar). The relative volume shift of mean and modal volume were calculated as a proportion coefficient of modal and mean values of the cell volume distributions by transition from iso-osmotic to hypo-osmotic conditions. The volumetric parameters related to the different cell subpopulations were derived from the different peaks of cell volume distributions. PI-staining techniques were used for comparison. The values of the volume shift and of derived percentages of the osmotically inactive cells were correlated negatively and positively, respectively (p < 0.05) with the percentage of the PI-stained cells. This correlation indicates that a relationship exists between membrane functions of the different cell compartments (sperm head and tail) due to the circumstance that the increase of the cell volume in the HOS-test is associated with the morphological changes in the tail and the PI-staining is associated with the membrane integrity and permeability of the head region. The advantage of computer-assisted volume measurement is that a large number of cells (5000,50 000 spermatozoa) can be measured and evaluated during one procedure and in a very short time. The relative volume shift is a quantitative continuous parameter characterizing the osmotic reactivity and membrane functional competence of a cell population and of subpopulations within one ejaculate. This parameter could be useful to evaluate membrane functional competence rapidly and sensitively. Inhalt Es ist eine generelle Eigenschaft membranintakter tierischer Zellen, mit einer Volumenzunahme auf eine hypoosmotische Belastung zu reagieren. Der auf der relativen Vergrößierungdes Zellvolumens basierende modifizierte hypoosmotischeSchwelltest ist ein indikativer Test zur Beurteilung der Membranintegrität mittels eines elektronischen Partikelzählers. In dieser Studie wurden die Zusammenhänge zwischen der mittels der Propidiumjodid-Färbung bestimmten Zellmembranintegrität und den osmotisch induzierten Veränderungen des Zellvolumens von Eberspermien untersucht. Volumenverteilungen von Eberspermien wurden unter isoosmotischen (300 mosmolar) und hypoosmotischen (150 mosmolar) Bedingungen gemessen. Die relative Volumenverschiebung der modalen und mittleren Werte der Volumenverteilung wurde als Quotient aus Modalwerten der Zellvolumenverteilungen und des mittleren Zellvolumens beim Übergang von isotonen zu hypotonen Bedingungen berechnet. Die auf verschiedene Subpopulationen bezogenen volumetrischen Parameter werden aus den originalen Volumenverteilungen berechnet. Der Betrag der Zellvolumenzunahme und die aus den Volumenverteilungen bestimmten Anteile an Zellen mit beschädigter Geißielmembran korrelierten signifikant negativ bzw. positiv (p < 0,05) mit dem Anteil an den Zellen mit beschädigter Kopfmembran, der sich aus der Propidiumjodid-Färbung ergab. Es wird geschlossen, daßi im Verhalten zwischen den Membranen der verschiedenen Zellkompartimente (Spermienkopf und-Geißiel) ein Zusammenhang besteht. Die beschriebene Methode ermöglicht die Analyse großier Zellpopulationen (5.000,50.000 Zellen). Die relative Volumenverschiebung stellt einen quantitativen kontinuierlichen Parameter dar, der den Membranzustand der Eberspermien einer Spermatozoenpopulation und Subpopulationen innerhalb eines Ejakulates charakterisiert. Diese Parameter können zur schnellen und sensitiven Beurteilung der Membranzustandes eingesetzt werden. [source] Functional Correlates of Fiber Architecture of the Lateral Caudal Musculature in Prehensile and Nonprehensile Tails of the Platyrrhini (Primates) and Procyonidae (Carnivora)THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 6 2009Jason M. Organ Abstract Prehensile-tailed platyrrhines (atelines and Cebus) and procyonids (Potos) display bony tail features that have been functionally and adaptively linked to their prehensile behaviors, particularly the need to resist relatively greater bending and torsional stresses associated with supporting their body weight during suspensory postures. We compared fiber architecture of the mm. intertransversarii caudae (ITC), the prime tail lateral flexors/rotators, in 40 individuals distributed across 8 platyrrhine and 2 procyonid genera, divided into one of two groups: prehensile or nonprehensile. We tested the hypothesis that prehensile-tailed taxa exhibit relatively greater physiologic cross-sectional areas (PCSAs) to maintain tail suspensory postures for extended periods. As an architectural trade-off of maximizing force, we also predicted prehensile-tailed taxa would exhibit relatively shorter, more pinnate fibers, and a lower mass to tetanic tension ratio (Mass/PO). Prehensile-tailed taxa have relatively higher PCSAs in all tail regions, indicating their capacity to generate relatively greater maximum muscle forces compared to nonprehensile-tailed taxa. Contrary to our predictions, there are no group differences in pinnation angles, fiber lengths or M/PO ratios. Therefore, the relatively greater prehensile PCSAs are driven largely by relative increase in muscle mass. These findings suggest that relatively greater ITC PCSAs can be functionally linked to the need for prehensile-tailed taxa to suspend and support their body weight during arboreal behaviors. Moreover, maximizing ITC force production may not come at the expense of muscle excursion/contraction velocity. One advantage of this architectural configuration is it facilitates suspension of the body while simultaneously maximizing tail contact with the substrate. Anat Rec, 292:827,841, 2009. © 2009 Wiley-Liss, Inc. [source] Trends during a half century in relative squamous cell carcinoma distribution by body site in the Swedish population: Support for accumulated sun exposure as the main risk factorTHE JOURNAL OF DERMATOLOGY, Issue 2 2008Henrik DAL ABSTRACT There is a strong relationship between squamous cell carcinoma (SCC) and exposure to ultraviolet radiation in terms of accumulated exposure. In this study, data from the Swedish Cancer Registry are surveyed to discern a reflection of behavioral and societal changes in relative distribution of SCC by body site. Data for the time period 1960,2004, including a total of 66 221 cases (56 669 people) were analyzed by body site for age and gender cohorts. The age-standardized (European population) incidence per 100 000 of SCC in the year 2004 was 30.4 in males and 15.4 in females. In the year 1960, the corresponding incidences were 7.7 and 3.8; that is, SCC has become four times more frequent in Sweden for both sexes during this period. The standardized incidence of SCC increased on all body sites except eyelids (men and women) and ears (women). Head tumors dominated among patients aged 70 years or more and diagnosed 1960,1964. Among patients less than 70 years old at diagnosis in 2000,2004, tumors of the trunk and limbs dominated. A relative increase of tumors of the scalp and neck was observed in all age groups (men), and of tumors of the trunk and upper limbs in all age groups and both sexes except among patients aged more than 90 years of age. In contrast, a relative decrease of tumors on the face (including the ears) was seen in all age groups. The relative increase of SCC of the trunk and upper limbs is a plausible reflection of intentional tanning. [source] Sodium imaging intensity increases with time after human ischemic stroke,ANNALS OF NEUROLOGY, Issue 1 2009Muhammad S. Hussain MD Objective Establishing time of onset is important in acute stroke management. Current imaging modalities do not allow determination of stroke onset time. Although correlations between sodium magnetic resonance imaging signal intensity within ischemic lesions and time of onset have been shown in animal models, the relation to onset time has not been established in human stroke. Utilizing high-quality sodium images, we tested the hypothesis that sodium signal intensity increases with time from symptom onset in human ischemic stroke. Methods Twenty-one stroke patients (63 ± 15 years old) were scanned 4 to 104 hours after symptom onset. Follow-up images were obtained in 10 patients at 23 to 161 hours after onset, yielding a total of 32 time points. A standard stroke imaging protocol was acquired at 1.5 Tesla, followed by sodium magnetic resonance imaging at 4.7 Tesla. Relative sodium signal intensity within each lesion was measured with respect to the contralateral side. Results The sodium image quality was sufficient to visualize each acute lesion (lesion volume range, 1.7,217cm3). Relative sodium signal intensity increased nonlinearly over time after stroke onset. Sodium images acquired within 7 hours (n = 5) demonstrated a relative increase in lesion intensity of 10% or less, whereas the majority beyond 9 hours demonstrated increases of 23% or more, with an eventual leveling at 69 ± 18%. Interpretation Increases of sodium signal intensity within the ischemic lesion are related to time after stroke onset. Thus, noninvasive imaging of sodium may be a novel metabolic biomarker related to stroke progression. Ann Neurol 2009;66:55,62 [source] Correlation of Electrical and Mechanical Reverse Remodeling after Cardiac Resynchronization TherapyANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2009Swapna Kamireddy M.D. Background: Cardiac resynchronization therapy (CRT) improves clinical outcome in many patients with refractory heart failure (HF). This study examined whether CRT is associated with reverse electrical remodeling by surface electrocardiogram (ECG). Methods: Consecutive CRT recipients at the University of Pittsburgh Medical Center with >90 days of follow-up were included in this analysis. ECG data were abstracted from medical records. Subjects with a relative increase of ,15% in left ventricular ejection fraction (LVEF) after CRT were considered responders. Results: A total of 113 patients (age 69 ± 11 years, men 70%, white 92%) were followed for a mean duration of 407 ± 290 (92,1439) days. Overall, LVEF increased after CRT (29 ± 13% vs 24 ± 9%; P < 0.01) and 50% of patients were responders. The mean native QRS interval among responders was higher than in nonresponders (163 ± 32 ms vs 148 ± 29 ms; P < 0.01). More than 3 months after CRT, there was no change in the paced QRS duration compared to baseline. Paced QRS duration, however, decreased among responders and increased among nonresponders and was significantly different by response status (P < 0.001). There was a significant correlation between increase in LVEF and decrease in paced QRS width in the overall population (r =,0.3; P < 0.01). Conclusions: Among responders to CRT, the paced QRS width decreases significantly, whereas it increases among nonresponders. Given the paced nature of the QRS, the improved conduction probably reflects enhanced cell-to-cell coupling after CRT as opposed to improved conduction within the His-Purkinje system. These findings have significant implications as to the mechanisms of benefit from CRT. [source] | |||||||||||||||||||||||||||||||||||||||||||