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Function Parameters (function + parameter)
Kinds of Function Parameters Selected AbstractsDo Muscle Mass, Muscle Density, Strength, and Physical Function Similarly Influence Risk of Hospitalization in Older Adults?JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2009Peggy Mannen Cawthon PhD OBJECTIVES: To examine the association between strength, function, lean mass, muscle density, and risk of hospitalization. DESIGN: Prospective cohort study. SETTING: Two U.S. clinical centers. PARTICIPANTS: Adults aged 70 to 80 (N=3,011) from the Health, Aging and Body Composition Study. MEASUREMENTS: Measurements were of grip strength, knee extension strength, lean mass, walking speed, and chair stand pace. Thigh computed tomography scans assessed muscle area and density (a proxy for muscle fat infiltration). Hospitalizations were confirmed by local review of medical records. Negative binomial regression models estimated incident rate ratios (IRRs) of hospitalization for race- and sex-specific quartiles of each muscle and function parameter separately. Multivariate models adjusted for age, body mass index, health status, and coexisting medical conditions. RESULTS: During an average 4.7 years of follow-up, 1,678 (55.7%) participants experienced one or more hospitalizations. Participants in the lowest quartile of muscle density were more likely to be subsequently hospitalized (multivariate IRR=1.47, 95% confidence interval (CI)=1.24,1.73) than those in the highest quartile. Similarly, participants with the weakest grip strength were at greater risk of hospitalization (multivariate IRR=1.52, 95% CI=1.30,1.78, Q1 vs. Q4). Comparable results were seen for knee strength, walking pace, and chair stands pace. Lean mass and muscle area were not associated with risk of hospitalization. CONCLUSION: Weak strength, poor function, and low muscle density, but not muscle size or lean mass, were associated with greater risk of hospitalization. Interventions to reduce the disease burden associated with sarcopenia should focus on increasing muscle strength and improving physical function rather than simply increasing lean mass. [source] Indocyanine green elimination but not bilirubin indicates improvement of graft function during MARS therapyCLINICAL TRANSPLANTATION, Issue 6 2007Stefan Scheingraber Abstract:, Measurement of indocyanine green plasma disappearance rate (PDRICG) has been suggested as a meaningful liver function parameter. However, there are only very limited data concerning its value in the monitoring of graft dysfunction (GDF) and primary non-function (PNF) especially during molecular absorbent recirculating system (MARS) therapy. This study was therefore performed to evaluate the diagnostic accuracy to detect and monitor GDF with the measurement of the PDRICG in direct comparison with conventional markers like bilirubin and prothrombin time (PT). Of the 19 liver recipients, four patients with GDF and two patients with PNF were treated with 38 MARS cycles. Only PDRICG did reliably indicate liver function between patients with GDF/PNF and patients with sufficient graft function who served as controls. Moreover, receiver operating characteristic analysis showed the highest areas under the curve (AUC) for PDRICG (AUCPDRICG max: 0.840, AUCPDRICG max: 0.822), followed by bilirubin (AUCbilirubin: 0.528) and PT (AUCPT: 0.546). In contrast to the decrease of the serum bilirubin concentration due to MARS, a noticeable improvement of PDRICG was evident only in patients with GDF. Patients with acute fulminant failure and PNF had significantly lower PDRICG values, which did not improve even during continuous MARS treatments. Conclusively, monitoring of PDRICG is superior to bilirubin and PT measurements to determine the graft function especially in patients with PNF and GDF undergoing MARS therapy. [source] Population dynamics and stock status of cobia, Rachycentron canadum, caught in Australian recreational and commercial coastal fisheriesFISHERIES MANAGEMENT & ECOLOGY, Issue 3 2010G. C. FRY Abstract, Age and growth of Rachycentron canadum (L.) was studied in northern and eastern Australia to provide data for a preliminary assessment of the stock and to explore possible fisheries management strategies using minimum legal lengths. Fish collected from commercial and recreational fisheries ranged in size and weight from 125 to 1633 mm fork length (FL) and 0.031 to 55 kg respectively. Annual growth increments in sectioned otoliths formed by November,December. Estimated ages ranged from 0 to 7 yr for both genders. Longevity was estimated to be at least 13 yr. Von Bertalanffy growth function parameters were L = 1160 mm FL, K = 0.63 yr,1 and t0 = ,0.21 yr,1. Rachycentron canadum reach 600 mm FL in their first year and over 1000 mm FL in 3 years. Natural and total mortalities were estimated at 0.35 yr,1 and 0.85 yr,1, respectively. Populations of R. canadum may be vulnerable to growth overfishing under the current minimum legal length of 750 mm total length (TL) in Queensland waters. An increase in minimum legal length to 850 mm TL is recommended. [source] Interpretation of Spring Recession CurvesGROUND WATER, Issue 5 2002H. Amit Recession curves contain information on storage properties and different types of media such as porous, fractured, cracked lithologies and karst. Recession curve analysis provides a function that quantitatively describes the temporal discharge decay and expresses the drained volume between specific time limits (Hall 1968). This analysis also allows estimating the hydrological significance of the discharge function parameters and the hydrological properties of the aquifer. In this study, we analyze data from perennial springs in the Judean Mountains and from others in the Galilee Mountains, northern Israel. All the springs drain perched carbonate aquifers. Eight of the studied springs discharge from a karst dolomite sequence, whereas one flows out from a fractured, slumped block of chalk. We show that all the recession curves can be well fitted by a function that consists of two exponential terms with exponential coefficients ,1 and ,2. These coefficients are approximately constant for each spring, reflecting the hydraulic conductivity of different media through which the ground water flows to the spring. The highest coefficient represents the fast flow, probably through cracks, or quickflow, whereas the lower one reflects the slow flow through the porous medium, or baseflow. The comparison of recession curves from different springs and different years leads to the conclusion that the main factors that affect the recession curve exponential coefficients are the aquifer lithology and the geometry of the water conduits therein. In normal years of rainy winter and dry summer, ,1 is constant in time. However, when the dry period is longer than usual because of a dry winter, ,1 slightly decreases with time. [source] Subclinical Left Ventricular Dysfunction in Migraine AttacksHEADACHE, Issue 1 2006Manuel Vidalón MD Objective.,The aim of the present study was to evaluate cardiac performance of patients with migraine attacks during the overload produced by phenylephrine infusion. Background.,It is known that circulatory changes occur during migraine. However, the relationship between this finding and transient cardiac dysfunction is still unknown. Methods.,By means of two-dimensional direct M-mode echocardiography, we measured fractional shortening, ejection fraction, and mean velocity of circumferential fibers shortening in 18 patients with migraine and in 10 normal subjects as a control group. These measures were performed in two different periods: during attack-free intervals and during attacks. Pain intensity of typical migraine attack was evaluated on a 0 to 10 scale. Results.,Cardiac size and function were normal at rest in both groups. However, during migraine attacks, phenylephrine infusion provoked significant decrease in fractional shortening, EF, and mean velocity of circumferential fibers shortening, followed by concomitant increase of headache severity. On the other hand, during the attack-free interval and in the control group phenylephrine infusion did not show significant changes in cardiac function parameters. Conclusions.,Our data suggest that left ventricular dysfunction during the phenylephrine test could participate in the complex pathophysiological mechanism of migraine attacks. [source] The effects of N-acetylcysteine on the expression of matrix metalloproteinase-2 and tissue inhibitor of matrix metalloproteinase-2 in hepatic fibrosis in bile duct ligated ratsHEPATOLOGY RESEARCH, Issue 12 2008Arezou Rezaei Aim:, N-acetylcysteine can inhibit the formation of intracellular reactive oxygen intermediates. Cellular redox state plays a role in regulating the secretion of matrix metalloproteinase-2. We investigated the effects of N-acetylcysteine on the expression of matrix metalloproteinase-2 and tissue inhibitor of matrix metalloproteinase-2. Methods:, Bile duct ligated rats were used as a model of hepatic fibrosis. We compared the level of gene expression (using real-time reverse transcription polymerase chain reaction [RT,PCR]), liver function parameters, hepatic reactive oxygen production, lipid peroxidation and glutathione state in experimental groups. Results:, N-acetylcysteine treatment significantly improved liver function parameters including the plasma levels of aspartate aminotransferase, alkaline phosphatase, gamma-glutamyl transpeptidase and bilirubin. In addition, significant improvement of glutathione state and reactive oxygen production were observed. Hepatic lipid peroxidation was reversed by N-acetylcysteine treatment. Although N-acetylcysteine treatment did not completely normalize the increased matrix metalloproteinase-2 expression, it significantly decreased its level by 65%. N-acetylcysteine treatment also significantly decreased matrix metalloproteinase-2 activity and normalized tissue inhibitor of matrix metalloproteinase-2 expression. Conclusion:, Collectively, N-acetylcysteine showed inhibition of matrix metalloproteinase-2 expression and activity. In addition, administration of N-acetylcysteine was associated with downregulation of the expression of tissue inhibitor of matrix metalloproteinase-2 and amelioration of oxidative stress in the liver of bile duct ligated rats. [source] Assessing the effects of measurement errors on the estimation of production functionsJOURNAL OF APPLIED ECONOMETRICS, Issue 6 2006Carmine Ornaghi This article explores to what extent the poor results that are often found when estimating parameters of production functions can be attributed to measurement errors, due to the use of common price deflators across firms. Because of the lack of detailed micro-economic data, econometricians have to rely on industry-wide deflators when computing outputs and intermediate inputs. A unique feature of the longitudinal data used in this paper is that it reports firm-level prices. This allows for a comparative assessment of production function parameters where the outputs and intermediate inputs are computed using both firm-specific prices and industry-wide deflators. The empirical results presented in this paper show that the use of common deflators across firms leads to lower scale estimates, mainly because of a large downward bias in the estimated coefficients for labour. Copyright © 2006 John Wiley & Sons, Ltd. [source] The renal effects of alginates isolated from brown seaweed Sargassum vulgareJOURNAL OF APPLIED TOXICOLOGY, Issue 3 2008Alessandra de Paula Alves Sousa Abstract Alginates isolated from Sargassum vulgare, present a strong antitumor activity, associated with kidney reversible damage, as analysed by histopathology of treated animals. In the present study, the renal alteration mechanisms of S. vulgare alginates were investigated using the isolated perfused rat kidney and the isolated perfused rat mesenteric blood vessel methods. The results showed that the effects of Sargassum vulgare low viscosity (SVLV) alginate were more potent than those of Sargassum vulgare high viscosity (SVHV) alginate in the isolated rat kidney. The SVLV alginate caused considerable changes in renal physiology, as shown by an increase in parameters such as perfusion pressure, renal vascular resistance, glomerular filtration rate, urinary flow and sodium, potassium and chloride excretion and by reduction of chloride tubular transport. The effects of SVHV were weaker than those of SVLV. The effects of SVLV on kidney could be related to direct vascular action as demonstrated with SVLV alginate on mesenteric blood vessels. In conclusion, the Sargassum vulgare alginate altered the renal function parameters evaluated. S. vulgare low viscosity alginate renal effects were more potent than S. vulgare high viscosity alginate. It is suggested that physicochemical differences between SVHV and SVLV could explain the differences found in the results. Copyright © 2007 John Wiley & Sons, Ltd. [source] A force-field description of short-range repulsions for high density alkane molecular dynamics simulationsJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 16 2004Joseph M. Hayes Abstract The use of Buckingham (exp-6) van der Waals potentials in molecular dynamics (MD) simulations can quite successfully reproduce experimental thermodynamic data at low densities. However, they are less successful in producing a description of the repulsive regions of the potential energy surface (PES) that is in accord with the results of high-level ab initio computations. We show that Morse potentials can be parameterized to give excellent fits to both the attractive and repulsive regions of the PES. The best set of alkane van der Waals Morse function parameters reported to date for the description of nonbond repulsive interactions is presented, as determined by comparison with both ab initio and experimental results. C,C, H,H and C,H atom-pair potentials employing parameter sets based on the use of the geometric mean in the fitting procedure are found to be portable from methane to n- butane. Fitting to a combination of methane dimer interaction energies and forces from ab initio calculations yields parameter sets whose performance is superior to those determined from the interaction energies alone. Used in MD simulations, our newly developed parameter sets predict thermodynamic functions that show better agreement with experiment than those based on parameter sets in common use. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1953,1966, 2004 [source] Platelet concentrates transfusion in cardiac surgery and platelet function assessment by multiple electrode aggregometryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2009N. RAHE-MEYER Background: Platelet dysfunction contributes to the pathophysiology of bleeding complications during and after cardiac surgery. In most surgical institutions, no peri-operative point-of-care monitoring of platelet function is used. We evaluated the usefulness of the Multiplate® platelet function analyser based on impedance aggregometry for identifying groups of patients at a high risk of transfusion of platelet concentrates (PC). Methods: Platelet function parameters were determined in 60 patients before and after routine cardiac surgery. Impedance aggregometry measurements were performed on Multiplate® using ADP (ADPtest), collagen (COLtest) and thrombin receptor activating peptide (TRAPtest) as platelet activators. The correlations between the aggregometry results and the transfusion of PC were calculated. The results of the aggregation tests were also divided into tertiles and the differences in PC transfusion between the low and the high tertile were assessed. Results: Low aggregometry delimited groups of patients with significantly higher PC transfusion. In the receiver operating characteristic curve, low pre-operative aggregation in the ADPtest identified patients with high total transfusion of PC (area under the curve 0.74, P=0.001), while the ADPtest performed at the end of the operation identified patients with high PC transfusion on the intensive care unit (ICU) (area under the curve 0.76, P=0.002). Conclusions: Near-patient platelet aggregation may allow the identification of patients with enhanced risk of PC transfusion, both pre-operatively and upon arrival on the ICU. [source] Fixed rank kriging for very large spatial data setsJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES B (STATISTICAL METHODOLOGY), Issue 1 2008Noel Cressie Summary., Spatial statistics for very large spatial data sets is challenging. The size of the data set, n, causes problems in computing optimal spatial predictors such as kriging, since its computational cost is of order . In addition, a large data set is often defined on a large spatial domain, so the spatial process of interest typically exhibits non-stationary behaviour over that domain. A flexible family of non-stationary covariance functions is defined by using a set of basis functions that is fixed in number, which leads to a spatial prediction method that we call fixed rank kriging. Specifically, fixed rank kriging is kriging within this class of non-stationary covariance functions. It relies on computational simplifications when n is very large, for obtaining the spatial best linear unbiased predictor and its mean-squared prediction error for a hidden spatial process. A method based on minimizing a weighted Frobenius norm yields best estimators of the covariance function parameters, which are then substituted into the fixed rank kriging equations. The new methodology is applied to a very large data set of total column ozone data, observed over the entire globe, where n is of the order of hundreds of thousands. [source] Use of the ,-function to estimate the skewness of species responsesJOURNAL OF VEGETATION SCIENCE, Issue 6 2003Branko Karad Abstract. Response of a species to an environmental variable may be modeled and predicted using a wide spectrum of different functions. Contrary to other functions (Gaussian, polynomial etc), all parameters of the ,-function are interpretable in ecological terms. However, computational difficulties in the determination of the ,-function parameters initiated controversial debates on the applicability and usefulness of this function in vegetation modelling and gradient analysis. We propose a simple algorithm for fitting the ,-function to observed data. Analytic properties of the algorithm (its ability to recover the known species responses along gradients) are tested using a series of simulated data. In most cases the algorithm correctly estimated parameters of the simulated responses. [source] Preliminary evaluation of hemostasis in neonatal foals using a viscoelastic coagulation and platelet function analyzerJOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue 1 2009Barbara L. Dallap Schaer VMD, DACVECC, DACVS Abstract Objectives , To compare coagulation and platelet function parameters measured using a viscoelastic analyzer in 3 groups: foals presenting to a neonatal intensive care unit with presumed sepsis, normal foals, and adult horses. Design , Preliminary prospective trial. Setting , Veterinary teaching hospital. Animals , Ten clinically healthy foals, 13 clinically healthy adult horses, and 17 foals sequentially admitted for suspected sepsis. Intervention , A single citrated (3.8%) blood sample collected at admission was submitted for coagulation evaluation using a viscoelastic analyzer. Measurements and Main Results , Time to initial clot formation (ACT), clot rate (CR), platelet function, and time to peak parameters were collected from the signature generated with the associated software. Peak clot strength was collected manually from signature tracings. Signalment, presenting complaint, blood culture results, clinical progression, and outcome were collected from the medical record. Kruskal-Wallis testing was used to determine differences in coagulation parameters between groups, as well as to identify any associations between coagulation variables, foal variables, and outcome. Normal foals were more likely to have increased platelet function (P=0.04) compared with normal adult horses. Prolonged ACT (P=0.004) and decreased CR (P=0.03) were associated with foals with positive blood culture. There was a trend toward prolonged ACT and increased likelihood of death (P=0.06). Conclusions , Healthy foals differ in values measured by the viscoelastic coagulation and platelet function analyzer compared with healthy adult horses. ACT and CR abnormalities were more likely to be observed in foals with positive blood cultures. The viscoelastic coagulation and platelet function analyzer may be useful in identifying early hemostasic and platelet dysfunction in critically ill foals, particularly those that are septic. [source] Improved rat steatotic and nonsteatotic liver preservation by the addition of epidermal growth factor and insulin-like growth factor-I to University of Wisconsin solutionLIVER TRANSPLANTATION, Issue 9 2010M. Amine Zaouali This study examined the effects of epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I) supplementation to University of Wisconsin solution (UW) in steatotic and nonsteatotic livers during cold storage. Hepatic injury and function were evaluated in livers preserved for 24 hours at 4°C in UW and in UW with EGF and IGF-I (separately or in combination) and then perfused ex vivo for 2 hours at 37°C. AKT was inhibited pharmacologically. In addition, hepatic injury and survival were evaluated in recipients who underwent transplantation with steatotic and nonsteatotic livers preserved for 6 hours in UW and UW with EGF and IGF-I (separately or in combination). The results, based on isolated perfused liver, indicated that the addition of EGF and IGF-I (separately or in combination) to UW reduced hepatic injury and improved function in both liver types. A combination of EGF and IGF-I resulted in hepatic injury and function parameters in both liver types similar to those obtained by EGF and IGF-I separately. EGF increased IGF-I, and both additives up-regulated AKT in both liver types. This was associated with glycogen synthase kinase-3, (GSK3,) inhibition in nonsteatotic livers and PPAR, overexpression in steatotic livers. When AKT was inhibited, the effects of EGF and IGF-I on GSK3,, PPAR,, hepatic injury and function disappeared. The benefits of EGF and IGF-I as additives in UW solution were also clearly seen in the liver transplantation model, because the presence of EGF and IGF-I (separately or in combination) in UW solution reduced hepatic injury and improved survival in recipients who underwent transplantation with steatotic and nonsteatotic liver grafts. In conclusion, EGF and IGF-I may constitute new additives to UW solution in steatotic and nonsteatotic liver preservation, whereas a combination of both seems unnecessary. Liver Transpl 16:1098,1111, 2010. © 2010 AASLD. [source] Preclinical experiment of auxiliary partial orthotopic liver transplantation as a curative treatment for hemophiliaLIVER TRANSPLANTATION, Issue 5 2005Saiho Ko The cause of hemophilia is deficiency of coagulation factor VIII production in the liver, which can be cured by liver transplantation. Because the hepatic function of hemophilia patients is quite normal except for production of factor VIII, auxiliary partial orthotopic liver transplantation (APOLT) is beneficial in that patient survival is secured by preserving native liver even in the event of graft loss. However, it is not known whether the graft of APOLT would be enough to cure hemophilia. We evaluated the efficacy and feasibility of APOLT for hemophilia in a canine hemophilia A model that we established. Partial left liver graft was taken from the normal donor (blood factor VIII activity > 60%). The graft was transplanted to the hemophilia beagle dog (blood factor VIII activity < 5%) after resection of the left lobe preserving native right lobe. Changes in time of blood factor VIII activity and liver function parameters were observed after APOLT. APOLT and perioperative hemostatic management were successfully performed. The blood factor VIII activity increased to 30% after APOLT, and was sustained at least 6 weeks throughout the observation period without symptoms of bleeding. The result demonstrated sustained production of factor VIII in the hemophilia recipient after APOLT. Transplantation of approximately one third of whole liver resulted in cure of hemophilia. In conclusion, it is suggested that APOLT would be feasible as a curative treatment of hemophilia A to improve quality of life of the patients. (Liver Transpl 2005;11:579,584.) [source] Bandpass filter modeling employing Lorentzian distributionMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2009Mahmoud Al Ahmad Abstract This letter takes a close outlook of modeling a bandpass filter performance with the Lorentzian distribution function. Lorentzian function parameters are correlated with the filter parameters, namely, its bandwidth and center frequency. The zeros and poles of the filter are extracted from the closed form expression of the Lorentzian function, which is used to construct the rational model of the filter. This procedure is expected to optimize the overall filter performance and to construct a consistent equivalent circuit from its computed poles and zeros. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1167,1169, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24288 [source] Safety, efficacy, and long-term results of a modified version of rapid opiate detoxification under general anaesthesia: A prospective study in methadone, heroin, codeine and morphine addictsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2000M. Hensel Background: In the present study a method of rapid opiate detoxification under general anaesthesia has been evaluated regarding the safety, the efficacy in preventing withdrawal symptoms, and the long-term results. In addition, it was investigated whether the profile and severity of withdrawal symptoms depend on the type of opiate abused (methadone, heroin, codeine, morphine). Methods: Seventy-two opiate addicts were detoxified in an intensive care unit (ICU). Anaesthesia was induced and maintained using propofol infusion. Patients were endotracheally intubated. The opiate receptor antagonist naltrexon was administered into the stomach via a nasogastric tube. Withdrawal symptoms before and after the detoxification treatment were assessed using an objective and a subjective opiate withdrawal scale (OOWS, SOWS). After detoxification patients entered a long-term naltrexone maintenance programme as well as a supportive psychotherapy programme. Vital organ function was monitored using haemodynamic and respiratory parameters as well as body temperature. Results: Organ function parameters were stable during the whole treatment in all patients and no anaesthetic complications were registered. Minor side effects such as bradycardia or hypotension were observed in 20 patients. Compared to patients with pre-existing heroin, codeine, or morphine abuse respectively, patients from the methadone maintenance programme had significantly higher (P<0.01) OOWS as well as SOWS values after the treatment. Twelve months after the detoxification 49 patients (68%) were abstinent from opiates whereas 17 patients had relapsed during the period of follow-up. Six patients were lost during follow-up. Conclusions: Rapid opiate detoxification under general anaesthesia is a safe and efficient method to suppress withdrawal symptoms. This treatment may be of benefit in patients who particularly suffer from severe withdrawal symptoms during detoxification and who have failed repeatedly to complete conventional withdrawal. Methadone patients have more withdrawal symptoms than other opiate addicts. [source] Echocardiographic evaluation of patients cured of childhood cancer: A single center study of 117 subjects who received anthracyclinesPEDIATRIC BLOOD & CANCER, Issue 6 2001Grazia Bossi MD Abstract Background The risk of cardiomyopathy following exposure to anthracycline in asymptomatic long-term survivors of childhood cancer is still hard to predict and precisely quantify. To identify the impact of different cumulative doses, even within a non-high dose range, and the echocardiographic parameters suitable for evaluating cardiac function, we studied diastolic and systolic echocardiographic parameters in a cohort of patients followed in a single center. Procedure A total of 117 subjects were studied at a median time of 7 years after treatment completion. A complete M-mode, two-dimensional and Doppler echocardiographic study was obtained at rest in all patients according to the standard recommendations of the American Society of Echocardiography. Results Ninety-nine patients (85%) had completely normal cardiac function, while 18 had abnormal echocardiographic findings: 12 had one abnormal value, 5 had two, and 1 had three abnormal values. All the changes were in left ventricular dimensions, wall thickness or indices of systolic function; no alterations in left ventricular diastolic function parameters were found. None of the echocardiographic parameters correlated significantly with the cumulative dose of anthracyclines administered either at univariate analysis or after adjusting for sex, body surface area or considered risk factors. Conclusions Subjects exposed to a median cumulative dose of 214,mg/m2 had no echographic abnormalities a median of 7 years later. We did not find any correlation between cumulative anthracycline dose and the echocardiographic parameters tested. We now offer echocardiographic follow-up to patients with mildly reduced fractional shortening and/or ejection fraction to rule out late onset dysfunction. Med. Pediatr. Oncol. 36:593,600, 2001. © 2001 Wiley-Liss, Inc. [source] Association of lower airway inflammation with physiologic findings in young children with cystic fibrosis,PEDIATRIC PULMONOLOGY, Issue 5 2009Stacey L. Peterson-Carmichael MD Abstract Background The relationship between lower airway markers of inflammation and infection with physiologic findings is poorly understood in young children with cystic fibrosis (CF). The goal of this study was to evaluate the association of bronchoalveolar lavage fluid (BALF) markers of infection and inflammation, including mediators linked to airway remodeling, to infant lung function values in young children with CF undergoing clinically indicated bronchoscopy. Methods Plethysmography and the raised volume rapid thoracoabdominal compression (RVRTC) technique were performed in 16 sedated infants and young children with CF prior to bronchoscopy. BALF was collected and analyzed for pathogen density, cell count, % neutrophils, transforming growth factor beta 1 (TGF-,1), matrix metalloproteinases (MMP), and interleukin-8 (IL-8). Results There was a significant direct correlation between functional residual capacity (FRC), the ratio of residual volume to total lung capacity (RV/TLC) and FRC/TLC with % neutrophils (P,<,0.05). Forced expiratory flows were inversely correlated to % neutrophils (P,<,0.01). Lung function parameters did not differentiate those with and without lower airway infection; however, pathogen density directly correlated with FRC and inversely correlated with flows (P,<,0.05). In a subset of the population, MMP-2 directly correlated with RV/TLC and inversely correlated with flows (P,<,0.05) and TGF-,1 directly correlated with FRC (P,<,0.05). Conclusions Results from this study suggest that lower airway inflammation as well as mediators linked to airway remodeling play an active role in pulmonary deterioration in CF infants and young children undergoing clinically indicated bronchoscopy. Pediatr Pulmonol. 2009; 44:503,511. © 2009 Wiley-Liss, Inc. [source] Lung Function Tests in Neonates and Infants with Chronic Lung Disease of Infancy: Functional Residual CapacityPEDIATRIC PULMONOLOGY, Issue 1 2006Georg Hülskamp MD Abstract This is the second paper in a review series that will summarize available data and discuss the potential role of lung function testing in infants and young children with acute neonatal respiratory disorders and chronic lung disease of infancy. The current paper addresses the expansive subject of measurements of lung volume using plethysmography and gas dilution/washout techniques. Following orientation of the reader to the subject area, we focus our comments on areas of inquiry proposed in the introductory paper to this series. The quality of the published literature is reviewed critically, and recommendations are provided to guide future investigation in this field. Measurements of lung volume are important both for assessing growth and development of lungs in health and disease, and for interpreting volume-dependent lung function parameters such as respiratory compliance, resistance, forced expiratory flows, and indices of gas-mixing efficiency. Acute neonatal lung disease is characterized by severely reduced functional residual capacity (FRC), with treatments aimed at securing optimal lung recruitment. While FRC may remain reduced in established chronic lung disease of infancy, more commonly it becomes normalized or even elevated due to hyperinflation, with or without gas-trapping, secondary to airway obstruction. Ideally, accurate and reliable bedside measurements of FRC would be feasible from birth, throughout all phases of postnatal care (including assisted ventilation), and during subsequent long-term follow-up. Although lung volume measurements in extremely preterm infants were described in a research environment, resolution of several issues is required before such investigations can be translated into routine clinical monitoring. Pediatr Pulmonol. © 2005 Wiley-Liss, Inc. [source] Randomized controlled trial of salbutamol aerosol therapy via metered dose inhaler-spacer vs. jet nebulizer in young children with wheezingPEDIATRIC PULMONOLOGY, Issue 5 2005J. Deerojanawong MD Abstract The jet nebulizer is a common device used for administering aerosol medication in young children. However, compared to a metered dose inhaler-spacer (MDI-spacer), it takes more time and personnel. This study aimed to compare the efficacy of salbutamol aerosol therapy given via these two devices in young wheezing children. A prospective randomized, double-blind, placebo-controlled trial was performed in children up to 5 years old who had acute wheezing and were admitted to the Department of Pediatrics, King Chulalongkorn Memorial Hospital. Patients were randomly divided into two groups. The first group received 2 puffs of placebo via MDI-spacer, followed by 0.15 mg/kg salbutamol respiratory solution via jet nebulizer. The second group received 2 puffs (100 ,g/puff) of salbutamol via MDI-spacer, followed by placebo via jet nebulizer. Clinical scores and tidal breathing pulmonary function test were evaluated before and after treatment. Pulmonary function parameters included those derived from flow volume loops (volume to peak tidal expiratory flow over total expiratory volume, VPTEF/VE; time to peak tidal expiratory flow over total expiratory time, TPTEF/TE; and ratio of tidal expiratory flow at 25% remaining expiration to peak expiratory flow, 25/PF), compliance (Crs), and resistance (Rrs) of the respiratory system. The efficacy of both methods was compared by using analysis of covariance. Forty-seven wheezing children were studied (24 received salbutamol via MDI-spacer, and 23 received it via jet nebulizer). There was no statistical difference between the two groups regarding clinical scores and all pulmonary function parameters. However, heart rate was significantly increased after treatment in the jet nebulizer group when compared to those in the MDI-spacer group (P,=,0.004). In conclusion, the efficacy of salbutamol aerosol therapy via MDI-spacer compared to jet nebulizer in young wheezing children was not different in terms of clinical score and postbronchodilator pulmonary function parameters. However, salbutamol aerosol therapy via jet nebulizer significantly increased the heart rate when compared to the MDI-spacer. © 2005 Wiley-Liss, Inc. [source] Childhood asthma: Exhaled markers of airway inflammation, asthma control score, and lung function testsPEDIATRIC PULMONOLOGY, Issue 2 2004Philippe P.R. Rosias MD Abstract Exhaled markers of airway inflammation become increasingly important in the management of childhood asthma. The aims of the present study are: 1) to compare exhaled markers of inflammation (nitric oxide, carbon monoxide, and acidity of breath condensate) with conventional asthma measures (lung function tests and asthma control score) in childhood asthma; and 2) to investigate the detectability of albumin, CRP, IL-6, IL-8, TNF-alpha, sICAM-1, and sTNF-R75 in the exhaled breath condensate (EBC) of asthmatic children. Thirty-two children with mild to moderate persistent asthma and healthy controls aged 6,12 years were studied. We measured exhaled NO and CO, and subsequently EBC was collected. Inflammatory mediators in EBC were measured using an enzyme-linked immunosorbent assay. Respiratory symptoms and asthma control were assessed using the asthma control questionnaire (ACQ) of Juniper et al. (Eur Respir J 1999;14:902,907). Exhaled NO showed a significant correlation with exhaled CO (r,=,0.59, P,<,0.05) and FEV1 (r,=,,0.59, P,<,0.05), but not with ACQ score (r,=,0.48, P,=,0.06). Exhaled CO was correlated with prebronchodilator FEV1 (r,=,,0.45, P,<,0.05), but not with asthma control (r,=,0.18, P,=,0.35). Acidity of EBC was significantly lower in asthmatic children than in healthy controls (P,<,0.05), but did not correlate with any of the conventional asthma measures. We were not able to demonstrate the presence of CRP, IL-6, IL-8, TNF-alpha, sICAM-1, and sTNF-R75 in EBC. Albumin was found in two EBC samples of asthmatic children. We conclude that exhaled NO had a better correlation with lung function parameters and asthma control than exhaled CO and acidity of EBC, in mild to moderate persistent childhood asthma. However, exhaled NO, CO, and deaerated pH of EBC did not differ between asthmatic children and controls, possibly because of a too homogeneous and well-controlled study population. To further evaluate the clinical utility of exhaled markers in monitoring childhood asthma, more studies are required on a wider range of asthma severity, and preferably with repeated measurements of markers and of asthma control. Pediatr Pulmonol. 2004; 38:107,114. © 2004 Wiley-Liss, Inc. [source] Retrospective review of children presenting with non cystic fibrosis bronchiectasis: HRCT features and clinical relationships,PEDIATRIC PULMONOLOGY, Issue 2 2003E.A. Edwards FRACP Abstract Non cystic fibrosis (CF) bronchiectasis in children presents with a spectrum of disease severity. Our aims were to document the extent and severity of disease in children with non-CF bronchiectasis, to review the inter- and intraobserver agreement for the high-resolution computed tomography (HRCT) features examined, and to assess correlations between HRCT features and clinical measures of severity. We performed a retrospective review of 56 children from the Starship Children's Hospital. HRCT scans were scored by a modified Bhalla system, and the chest X-rays using the Brasfield score. Scores were correlated with demographics, number of hospitalizations, disease duration, pulmonary function, clinical examination, and chronic sputum infection. The bronchiectasis seen was widespread and severe, particularly in Maori and Pacific Island children. The kappa coefficient for intraobserver agreement was better than that for interobserver agreement. Comparisons between HRCT scan and lung function parameters showed that the strongest relationships were between forced expiratory volume in 1 sec (FEV1) and forced expiratory flow between 25,75% of forced vital capacity (FEF25,75) with the extent of bronchiectasis, bronchial wall thickening, and air trapping. Children with digital clubbing and chest deformity showed significantly higher scores for extent of bronchiectasis, bronchial wall dilatation and thickness, and overall computed tomography (CT) score. No relationship was demonstrated between chronic sputum infection and CT score. The HRCT score demonstrated a stronger correlation between the extent and severity of bronchiectasis, and spirometry values, than the chest X-ray score. In conclusion, pediatric non-CF bronchiectasis in Auckland is extensive and severe. The good intraobserver ratings mean that consistency of scoring is possible on repeated scans. This study cannot comment on the relationships of CT and less severe disease. Pediatr Pulmonol. 2003; 36:87,93. © 2003 Wiley-Liss, Inc. [source] Extended-stay hospitalization for childhood asthma in JapanPEDIATRICS INTERNATIONAL, Issue 4 2009Hidekazu Tani Abstract Background:, While recent advances in asthma management have enabled adequate control to be frequently achieved in outpatient settings, children whose asthma remains poorly controlled despite outpatient treatment are often referred to extended-stay hospitals. The aim of the present study was to examine trends concerning extended-stay hospitalization and to evaluate the present status of this approach. Methods:, A retrospective study was conducted to assess changes in the number of admissions among 408 children with extended stays at Kamiamakusa General Hospital between 1989 and 2005. Medical and laboratory data of 236 patients admitted since 1994 were obtained from clinical records. Results:, The number of children with extended-stay hospitalizations since 2000 declined dramatically compared with the early 1990s, while the percentage of patients with complications of childhood asthma, such as severe atopic dermatitis, school absenteeism, and obesity, have increased significantly in the recent past. Practical benefits of extended-stay hospitalization were demonstrated by significant improvement of exercise performance and measurement of pulmonary function parameters and serum IgE concentrations by time of discharge. In addition to improvement in asthmatic symptoms, maintenance drug requirements and frequency of school absenteeism were reduced. Conclusions:, The medical mission of extended-stay hospitalizations is currently limited due to the availability of improved pharmacotherapy. Some patients, however, with exceptionally severe asthma or psychological problems that interact with their medical condition still fare poorly under outpatient care and could benefit from group care. Further study is needed to identify the components of long-term programs essential to produce change. [source] Influence of occupational factors on lung function in french dairy farmers.AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 4 2006A 5-year longitudinal study Abstract Background Dairy farming is associated with a high prevalence of respiratory disorders but the respective influence of occupational exposures, environmental, and individual factors on lung function remain unclear. Methods In 1994 and 1999, dairy farmers were examined in the Doubs province, France. Spirometric measures and allergological tests were performed. Medical and professional data were obtained by questionnaires. A multiple linear regression analysis was performed. Results An accelerated decline in lung function parameters was associated with age, male sex, traditional farm (as opposed to modern farms), and a high rate of total IgE (P,<,10,2). Blood oxygen saturation (SpO2) was significantly positively linked with the modernization of the farm and negatively with age, smoking status, and log IgE (P,<,10,2). Geographical factors (altitude and climatic conditions) had no significant effect. Conclusions The modernization of the farm has an important and beneficial impact on lung functiony. Am. J. Ind. Med. 49:231,237, 2006. © 2006 Wiley-Liss, Inc. [source] Semen quality and sperm functional parameters in fertile Indian menANDROLOGIA, Issue 1 2006P. C. Pal Summary The reports of a decline in the reproductive health of men worldwide prompted the present study to be undertaken so that baseline semen parameters could be established in Indian men. Semen profile and sperm function parameters were evaluated in 368 Indian men of proven fertility, settled in Delhi. The results of the study were compared with available published information from Indian men. The mean sperm concentration and semen volumes were 68.22 ± 15.14 × 106 ml,1 and 3.20 ± 0.94 ml, respectively. Rapid, linear progressive motility and sluggish linear motility were 40.95 ± 9.15% and 24.95 ± 7.01%, respectively. A comparison of the results of the present study with earlier published data did not support the contention of a decrease in the semen quality in Indian men. [source] Effects of Hormone Replacement Therapy on Heart Rate Variability in Postmenopausal WomenANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 4 2001Aylin Yildirir M.D. Background: Hormone replacement therapy (HRT) is associated with reduced cardiovascular risk, but the underlying mechanism(s) are not fully understood. This study investigated the effects of a 6-month course of HRT on cardiac autonomic function parameters assessed by heart rate variability (HRV) in postmenopausal women. Methods: Forty-six healthy postmenopausal women (age 48 ± 5, range 40,60) with normal baseline electrocardiogram and negative exercise testing were enrolled. HRT, which was either 0.625 mg/day conjugated equine estrogen (CEE) plus 2.5 mg/day medroxyprogesterone acetate or 0.625 mg/day CEE alone were administered depending on hysterectomy status. Power spectral analysis of HRV was performed to calculate the low frequency component in absolute (LF) and normalized units (LF nu), high frequency component in absolute (HF), and normalized units (HF nu), and the LF/HF ratio. The standard deviation of RR intervals (SDNN) was calculated from the time series of RR intervals. Results: A 6-month course of HRT did not significantly alter resting heart rate (P > 0.05). The LF/HF ratio and LF nu significantly decreased after HRT (P = 0.022 and P = 0.032), whereas a significant increase was noted in the HF component of HRV (P = 0.043), indicating an improvement in cardiac autonomic function. The SDNN value, which was 28.8 ± 11.8 ms before HRT significantly increased to 35.4 ± 16.7 ms after 6 months (P = 0.011). Conclusion: Our results indicate that a 6-month course of HRT may significantly improve cardiac autonomic function parameters, a finding that could at least partly explain the potential cardiopro-tective effect(s) of HRT. A.N.E. 2001;6(4):280,284 [source] Biological Activity of Endogenous Atrial Natriuretic Peptide During Cardiopulmonary BypassARTIFICIAL ORGANS, Issue 10 2000Nobuhiko Hayashida Abstract: To evaluate the effect of cardiopulmonary bypass (CPB) on atrial natriuretic peptide (ANP) biological activity in patients undergoing cardiac operations, we conducted a prospective study. Ten patients undergoing mitral valve surgery were enrolled. Plasma levels of ANP and cyclic guanosine monophosphate (cGMP), hemodynamic variables, and renal function parameters were assessed perioperatively. The molar ratio of cGMP to ANP (as a marker for ANP biological activity) decreased significantly (p < 0.05) during CPB despite similar plasma ANP levels. The ratio correlated inversely with the duration of CPB (r = ,0.85, p = 0.002). The ratio also correlated with fractional sodium excretion (r = 0.65, p = 0.04) and correlated inversely with pulmonary vascular resistance (r = ,0.79, p = 0.009) and atrial filling pressure (r = ,0.84, p = 0.003) postoperatively. CPB decreased the molar ratio of cGMP to ANP, which may represent ANP biological activity, such as vasodilation and natriuresis. The phenomenon may contribute to water,sodium retention and pulmonary hypertension after cardiac surgery. [source] Choice experiment adaptive design benefits: a case study,AUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 4 2010Geoffrey N. Kerr Efficient experimental designs offer the potential to reduce required sample sizes, or to reduce confidence intervals for parameters of interest, in choice experiments. Choice experiment designs have typically addressed efficiency of utility function parameter estimates. The recently developed concept of C -efficiency recognises the salience of willingness to pay estimates rather than utility function parameters in studies that seek to put money values on attributes. C -efficiency design benefits have been illustrated in a theoretical context, but have not been tested in applied settings. This study reports a choice experiment field application that used initial responses to update statistical designs to maximise C -efficiency. Consistent with theoretical predictions, the revised design delivered significant reductions in the variance of willingness to pay estimates, illustrating that C -efficient designs can indeed decrease costs of choice experiments by reducing required sample sizes. [source] Prediction of posthepatectomy hepatic functional reserve by serum hyaluronateBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 5 2009S. Yachida Background: Serum hyaluronate can be used as an index of hepatic sinusoidal endothelial cell function and hepatic fibrosis. This study was designed to clarify the clinical significance of the serum hyaluronate level as a parameter of functional reserve. Methods: The study included 283 patients undergoing hepatectomy. Liver function parameters were examined before surgery and compared with outcomes. Patients were retrospectively grouped according to the presence or absence of postoperative hepatic dysfunction. Results: Preoperative serum hyaluronate levels were significantly raised in parallel with the degree of severity of the underlying chronic liver disease. Regression analysis revealed serum hyaluronate level to be an independent predictor of portal hypertension. In 131 patients undergoing major hepatectomy, preoperative hyaluronate levels were significantly higher in patients with poor outcome. Multivariable logistic regression analysis demonstrated serum hyaluronate and total bilirubin levels to be independent variables associated with postoperative hepatic dysfunction. Patients with high indocyanine green retention rate at 15 min (over 15 per cent) showed significantly higher morbidity and mortality rates when their serum hyaluronate levels were over 180 ng/ml. Conclusion: Serum hyaluronate is a simple clinical marker for portal venous pressure and a reliable auxiliary parameter of hepatic functional reserve in combination with other liver function tests. Copyright © 2009 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||||||||||||||