bluuebunny/crossref_metadata_2025 huggingface dataset:
Microsurgical Techniques for Lymphedema Treatment: Derivative Lymphatic‐Venous Microsurgery
Authors: Campisi Corradino , Boccardo Francesco
Published: May 2004

We analyzed clinicopathologic and imaging features of chronic peripheral lymphedema to identify imaging findings indicative of its exact etiopathogenesis and to establish the optimal treatment strategy. One of the main problems of microsurgery for lymphedema is the discrepancy between the excellent technical possibilities and the subsequently insufficient reduction of the lymphedematous tissue fibrosis and sclerosis. Appropriate treatment based on pathologic studies and surgical outcome have not been adequately documented. Over the past 25 years, 676 patients with peripheral lymphedema have been treated with microsurgical lymphatic‐venous anastomoses. Of these patients, 447 (66%) were available for long‐term follow‐up study. Objective assessment was undertaken by water volumetry and lymphoscintigraphy. Objectively, volume changes showed a significant improvement in 561 patients (83%), with an average reduction of 67% of the excess volume. Of the 447 patients followed, 380 (85%) have been able to discontinue the use of conservative measures, with an average follow‐up of more than 7 years and average reduction in excess volume of 69%. There was an 87% reduction in the incidence of cellulitis after microsurgery. Microsurgical lymphatic‐venous anastomoses have a place in the treatment of peripheral lymphedema and should be the therapy of choice in patients who are not sufficiently responsive to nonsurgical treatment. Improved results can be expected with operations performed early, during the first stages of lymphedema.
Cost‐effectiveness of Two Follow‐up Strategies for Curative Resection of Colorectal Cancer: Comparative Study Using a Markov Model
Authors: Borie Frédéric , Combescure Christophe , Daurès Jean‐Pierre , Trétarre Brigitte , Millat Bertrand
Published: May 2004

The follow‐up of patients with curative resection of colorectal cancer is still controversial. The means mobilized for postoperative monitoring come at a high cost. However, the modalities are neither formalized nor validated with regard to an improved 5‐year survival rate. To compare the cost‐effectiveness of both strategies for patient follow‐up during the 7 years following curative resection of colorectal cancer, we performed a cost‐effectiveness analysis adjusted for quality of life. Using data from the literature and a population study, a simulation of follow‐up on patients who had undergone curative resection of colorectal cancer was carried out over a 7‐year period using a Markov model. Two Markov processes were modeled to compare the cost‐effectiveness ratio adjusted for quality of life in patients with a follow‐up in accordance with the recommendations of the 1998 French Consensus Conference (standard follow‐up) with the carcinoembryonic antigen (CEA) assay and a simplified follow‐up. The influence of standard follow‐up on the quality‐adjusted life expectancy of patients who had Duke’s stage A and B colorectal cancer appears to be modest, with increases of 2.5 monthsand 1.3 months, respectively; it is more acceptable for patients who had had Duke’s stage C, with an increase of 11 months. The high variability of cost‐effectiveness ratios (> 7 years) of ± 44,830 and 180,195 € per quality‐adjusted life‐years (QALY), respectively) did not favor the standard follow‐up. The cost‐effectiveness ratio (> 7 years) of patients having had Duke’s stage C colorectal cancer was 1,058 (sd: 2746) € per QALY and could favor the standard follow‐up. This study showed that standard follow‐up with CEA assay tended to preferentially improve the survival of Duke’s stage C patients. The type of examination needed and the frequency with which it has to be carried out should take account of the stage, treatment for the initial illness, and the patient’s age.
Improved Prognosis of Resected Esophageal Cancer
Authors: Stein Hubert J. , Siewert Jörg‐Rüdiger
Published: May 2004

Because of the perceived high risk of esophagectomy and the assumed poor long‐term results, the role of surgical resection as the mainstay of treatment for localized esophageal cancer is currently being challenged. Early tumors are increasingly approached by endoscopic mucosectomy or mucosal ablation techniques, whereas combined radiochemotherapy without surgery has become the treatment of choice for locally advanced tumors at many institutions. Several recent reports and our experience, however, indicate that surgical resection of esophageal cancer has become a safe procedure and long‐term survival rates after surgical resection have improved markedly during the past two decades. A number of factors have been associated with the marked reduction in postoperative mortality and improved long‐term survival after surgical resection. They include changes in the epidemiology with an increased rate of adenocarcinoma mostly located distally, patient selection for surgery, improvements in surgical technique and perioperative management, and the use of neoadjuvant treatment protocols. The treatment strategy and extent of the surgical procedure can now be tailored based on histologic tumor type, tumor location, tumor stage, and the general condition of the patient. With an individualized approach, surgical resection of esophageal cancer can predictably offer cure. Surgical resection thus remains the major pillar in the successful treatment of esophageal cancer.
Effect of a landfill on the home range and group size of coyotes (Canis latrans) in a tropical deciduous forest
Authors: Hidalgo‐Mihart Mircea G. , Cantú‐Salazar Lisette , López‐González Carlos A. , Fernandez Erin C. , González‐Romero Alberto
Published: April 2004

The effect of an open landfill and the seasonality of a tropical deciduous forest in Jalisco, Mexico, was tested on the home range and group size of coyotesCanis latransunder the Resource Dispersion Hypothesis (RDH), which proposes that in social carnivores dispersion of patches of limited resources determines home‐range size, whereas independently, abundance of resources affects group size. The predictions in this study were that coyotes using the landfill, where food is available all year due to the continuous arrival of food wastes that are concentrated in a single patch, would have smaller, seasonally constant home ranges than coyotes living outside, where food is distributed in several patches. In this area, coyotes would increase their home ranges during the dry season due to seasonal changes in resource availability. Also, a larger coyote group size should exist in the landfill, where food abundance is greater. Home‐range size and group size of coyotes living in and outside the landfill were estimated by radio‐tracking. Home ranges of coyotes in the landfill varied from 0.9 to 9.5 km2, whereas home‐range sizes of coyotes outside the landfill varied from 10.9 to 43.7 km2. Seasonality had no effect on the home‐range sizes. We identified a group of four adult coyotes in the landfill and no group formation in coyotes outside. These results support the predictions about home‐range and group size of coyotes in relation to landfill presence, and indicate that under the circumstances of our study, coyotes follow the postulates proposed by the RDH.
Effects of antimicrobial agents on oral biofilms in a saliva-conditioned flowcell
Authors: Foster J. S. , Pan P. C. , Kolenbrander P. E.
Published: May 2004

Oral bacteria form mixed-species biofilms known as dental plaque. Growth of these complex microbial communities is often controlled with the use of antimicrobial mouthrinses. Novel laboratory methods for testing the efficacy of antimicrobials in situ are necessary to complement current clinical testing protocols. In this study, we examined the effects of antimicrobial agents on a streptococcal biofilm grown in a saliva-conditioned flowcell. The flowcell coupled with confocal laser scanning microscopy enabled examination of growing oral biofilms in situ without disruption of the microbial community. Biofilms composed of Streptococcus gordonii DL1 were grown in an in vitro flowcell and treated with several commercially available antimicrobial mouthrinses containing essential oils, triclosan, cetylpyridinium chloride/domiphen or chlorhexidine. The results of this study revealed varying abilities of the antimicrobial agents to cause cellular damage on the growing biofilm in situ. This study therefore demonstrated the usefulness of the flowcell in the rapid assessment of antimicrobial efficacy.
Growth limitation of Staphylococcus epidermidis in biofilms contributes to rifampin tolerance
Authors: Zheng Z. , Stewart P. S.
Published: May 2004

Tolerance of Staphylococcus epidermidis in biofilms to killing by rifampin was correlated with limitation of bacterial growth in the biofilm state. Intact biofilm experienced a 0.62 log reduction when treated with 0.1 μg rifampin/ml for 4 h whereas the same treatment of exponential-phase planktonic cells produced a log reduction of 4.48. Stationary-phase planktonic cells were nearly as tolerant as intact biofilm cells, experiencing a 1.11 log reduction. Biofilm bacteria grew at only 10% of the maximum rate at which they grew on the same medium in planktonic culture. Killing was localized near the surface of the biofilm adjacent to the nutrient source, as revealed by staining with a respiratory dye. Increased nutrient concentration during antibiotic treatment enhanced killing of biofilm cells. Changing the oxygen tension in the gas phase above the biofilm during antibiotic treatment barely affected killing. It was hypothesized that the biofilm harbors significant numbers of stationary-phase-like cells in the nutrient-limited depths of the biofilm, and that these inactive cells are the ones that survive antibiotic challenge.
Rheology of biofilms formed from the dental plaque pathogen Streptococcus mutans
Authors: Vinogradov A. M. , Winston M. , Rupp C. J. , Stoodley P.
Published: May 2004

Here we describe an experimental study of the mechanical properties of bacterial biofilms formed from the early dental plaque colonizer Streptococcus mutans. The S. mutans biofilms demonstrated the behavior of rheological fluids, with properties similar to those of organic polymers and other biological fluids. The time-dependent response of the biofilms was modeled on the basis of principles of viscoelasticity theory. The static and dynamic responses were defined in terms of the creep compliance, storage and loss moduli, and viscosity. The creep compliance and stress relaxation functions of S. mutans biofilms were characterized using the Burger model. Implications for developing more effective mechanical removal strategies of dental plaque biofilms are discussed.
Removal of lead and cadmium by derivatized polysaccharides from Klebsiella oxytoca
Authors: Bamberg K. M. , Winter W. T. , Nakas J. P.
Published: May 2004

Extracellular polysaccharide (EPS) from Klebsiella oxytoca was chemically modified to increase net negative charge in order to expand the efficiency of metal binding. Chlorosulfonic acid (CSA) or a complex of dimethylformamide and sulfur trioxide (DMF–SO3) was used to introduce sulfate substituents onto the native polymer. Additionally, sequential treatment with divinylsulfone (DVS) and glycine or DVS and iminodiacetic acid (IDA) was used to introduce carboxyl residues. Native EPS exhibited a molecular mass distribution of 1500–1700 kDa and removed 38% and 19%, respectively, of lead and cadmium ions. Modification with CSA resulted in a reduction of molecular mass to 450–600 kDa and a removal from solution of lead and cadmium of 75% and 66%, respectively. Modification of EPS with the DMF–SO3 complex, while it did not affect the molecular mass of the polymer, resulted in decreased levels of lead and cadmium removal. Covalent substitution of EPS with DVS–glycine resulted in an increase of molecular mass to 3000 kDa and lead and cadmium removals of 46% and 47%, respectively. Modification of EPS with DVS–IDA increased molecular mass to 2200 kDa and demonstrated lead and cadmium removals of 57% each. Immobilization of native EPS and of the CSA and DVS–IDA modifications to oxirane–acrylic beads resulted in significant increases in metal binding per gram of bound polymer. This suggests a method for metal ion recovery using chelate desorption.
Modeling the nitrogen cycling and plankton productivity in the Black Sea using a three‐dimensional interdisciplinary model
Authors: Grégoire M. , Soetaert K. , Nezlin N. , Kostianoy A.
Published: May 2004

A six‐compartment ecosystem model defined by a simple nitrogen cycle is coupled with a general circulation model in the Black Sea so as to examine the seasonal variability of the ecohydrodynamics. Model results show that the annual cycle of the biological productivity of the whole basin is characterized by the presence of a winter–early spring bloom. In all the regions this bloom precedes the onset of the seasonal thermocline and occurs as soon as the vertical winter mixing decreases. Phytoplankton development starts in winter in the central basin, while in coastal areas (except in the river discharge area) it begins in early spring. In the Danube's discharge area and along the western coast, where surface waters are almost continuously enriched in nutrient by river inputs, the phytoplankton development is sustained during the whole year at the surface. The seasonal variability of the northwestern shelf circulation induced by the seasonal variations in the Danube discharge and the wind stress intensity has been found to have a major impact on the primary production repartition of the area. In the central basin the primary production in the surface layer relies essentially on nutrients being entrained in the upper layer from below. Simulated phytoplankton concentrations are compared with satellite and field data. It has been found that the model is able to reproduce the main characteristics of the space‐time evolution of the Black Sea's biological productivity but underestimates the phytoplankton biomass especially in regions extremely rich in nutrients such as the Danube discharge area.
First observations of increased ultrafine particle number concentrations near the inversion of a continental planetary boundary layer and its relation to ground‐based measurements
Authors: Siebert Holger , Stratmann Frank , Wehner Birgit
Published: May 2004

Results of the first balloon‐borne profile measurements of particle number concentrations, together with fine‐scale measurements of temperature and water vapor density under cloudless conditions are reported. The profiles showed regions near the inversion of a continental planetary boundary layer with high particle number concentrations of up to 600 cm−3 in the size range from 5 to 10 nm. These high concentrations of ultrafine particles correlated well with high fluctuations of the temperature and humidity caused by plumes penetrating the inversion. Such penetration caused intensive mixing, which in turn apparently significantly increased the nucleation rate. The observed particle number concentrations near the inversion layer were significantly higher than that in the mixed layer and at ground level. This corroborates the hypothesis that particles are formed near this inversion.
Earthquakes and relative sealevel changes
Authors: Melini D. , Piersanti A. , Spada G. , Soldati G. , Casarotti E. , Boschi E.
Published: May 2004

Using a spherical model of postseismic deformation, for the first time we have computed the global contribution of large earthquakes to the relative sealevel variations in the twentieth century. We have found that great earthquakes have the overall tendency to produce a sealevel rise, and that they affect the measurements taken at those tide‐gauge sites that are commonly employed to obtain global estimates of sealevel rise. Though on a global scale most of the signal is associated with thrust events, on a regional scale the effects of great transcurrent earthquakes cannot be neglected. Depending on the viscosity of the asthenosphere, the contribution of earthquakes to the long‐term sealevel changes amounts to at least 0.1 mm/yr. Thus, the climate‐driven long‐term sealevel changes deduced by tide‐gauge observations may be slightly, but not negligibly, overestimated.
Flow shear near the boundary of the plasma sheet observed by Cluster and Geotail
Authors: Nakamura R. , Baumjohann W. , Nagai T. , Fujimoto M. , Mukai T. , Klecker B. , Treumann R. , Balogh A. , Rème H. , Sauvaud J. A. , Kistler L. , Mouikis C. , Owen C. J. , Fazakerley A. N. , Dewhurst J. P. , Bogdanova Y.
Published: May 2004

We report on the transient strong flow shear (large northward/southward electric field) events accompanied by energetic ion beams and localized field‐aligned currents observed at the boundary of the premidnight plasma sheet by Cluster in the Northern Hemisphere and Geotail in the Southern Hemisphere. The events took place associated with plasma sheet expansion during a substorm interval, with the main positive bay onset at 1155 UT on 10 October 2001. Typical timescales of these events were 1–5 minutes. Cluster multipoint analysis showed that the field‐aligned currents consist of upward and downward current layers, the latter located at the outermost edge of the plasma sheet and concentrated in a region with a thickness of 1600 km. Low‐energy proton flow suggested that the electric field was southward at the outer part and northward at the inner part, with a magnitude exceeding 10 mV/m. The electric field reversal region also corresponds to the boundary between beam‐like electrons and more isotropic electron distributions. Geotail observed corresponding plasma and field disturbances simultaneously inside the plasma sheet. We suggest that the strong bipolar electric fields could be related to the Hall effect of the transient reconnection process tailward of Cluster and Geotail and to the leading edge of the plasma flow jetting Earthward from the reconnection region.
Compaction, dilatancy, and failure in porous carbonate rocks
Authors: Vajdova Veronika , Baud Patrick , Wong Teng‐fong
Published: May 2004

The analysis of dilatant and compactant failure in many sedimentary and geotechnical settings hinges upon a fundamental understanding of inelastic behavior and failure mode of porous carbonate rocks. In this study we acquire new mechanical data on the Indiana and Tavel limestones, which show that the phenomenology of dilatant and compactant failure in these carbonate rocks is similar to that of the more compact Solnhofen limestone as well as sandstones. Compressibility and porosity are positively correlated. Brittle strength decreases with increasing porosity and the critical stresses for the onset of pore collapse under hydrostatic and nonhydrostatic loadings also decrease with increasing porosity. Previously, two micromechanical models were used to interpret mechanical behavior of Solnhofen limestone: viewing cataclasis and crystal plasticity as two end‐members of inelastic deformation mechanisms, the wing crack and plastic pore collapse models were applied to brittle and ductile failure, respectively. Synthesizing published data for carbonate rocks with porosities between 3% and 45%, we investigate to what extent the same micromechanisms may be active at higher porosity. Application of the plastic pore collapse model indicated that crystal plasticity cannot be the only deformation mechanism. To arrive at a more realistic interpretation of shear‐enhanced compaction in porous carbonate rocks cataclastic processes must be taken into account. We infer that mechanical twinning dominates in the more porous limestones and chalk, while dislocation slip is activated in the more compact limestones.
Nonlinear resonant coupling between two adjacent bays
Authors: Marcos Marta , Liu Philip L.‐F. , Monserrat Sebastià
Published: May 2004

Field evidences of the nonlinear resonant coupling between two adjacent basins are found in two elongated inlets in the region of Ciutadella, Menorca Island, in the western Mediterranean. Sea level measurements reveal different amplification responses during calm periods (when a linear approach is justified) and during “rissaga” events (when sea level oscillations inside the bays reach amplitudes comparable to water depth and nonlinear effects are expected to play a significant role). These differences are then interpreted as the observational manifestation of the nonlinear coupling between two adjacent inlets. This phenomenon is studied using a simplified analytical model consisting of two parallel and rectangular adjacent inlets with constant depth. Weakly nonlinear and weakly dispersive waves are considered. Therefore Boussinesq equations may be employed for the analysis. The problem is further simplified by assuming that the waves outside the bays are linear so that the wave fields inside the bays can be described by a system of coupled nonlinear two‐point boundary value problems with complex coefficients for each harmonic. The nonlinear system is solved numerically, and the solutions are used to investigate the coupling under linear and nonlinear wave conditions.
Solibore‐induced sediment resuspension in the Faeroe‐Shetland Channel
Authors: Hosegood Phil , Bonnin Jérôme , van Haren Hans
Published: April 2004

High resolution measurements of temperature and current velocity over the seabed in the Faeroe‐Shetland Channel (FSC) reveal an intense internal wave train, referred to as a solibore, propagating up the continental slope. In addition to enhancing turbulent mixing, a rotor formed at the leading edge of the solibore generates sediment fluxes O(102) greater than background levels. The interaction of solibores, which appear to evolve from baroclinic bores, with the seabed and the resulting rotor provides a dominant mechanism for the upward transport of sediment over continental slopes that may counteract downward avalanching of material by gravity.
The effect of velocity structure errors on double‐difference earthquake location
Authors: Michelini A. , Lomax A.
Published: May 2004

We show that relative earthquake location using double‐difference methods requires an accurate knowledge of the velocity structure throughout the study region to prevent artifacts in the relative position of hypocenters. The velocity structure determines the ray paths between hypocenters and receivers. These ray paths, and the corresponding ray take‐off angles at the hypocenters, determine the partial derivatives of travel time with respect to the hypocentral coordinates which form the inversion kernel that maps double‐differences into hypocentral perturbations. Thus the large‐scale velocity structure enters into the core of the double‐difference technique. By employing a 1D layered model with sharp interfaces to perform double‐difference inversion of synthetic data generated using a simple, 1D gradient model; we show that inappropriate choice of the velocity model, combined with unbalanced source‐receiver distributions, can lead to significant distortion and bias in the relative hypocenter positions of closely spaced events.
Prevalence and correlates of stunting among children in rural Pakistan
Authors: SHAH SYED M , SELWYN BEATRICE J , LUBY STEPHEN , MERCHANT ANWAR , BANO RASHIDA
Published: May 2004

Abstract

Background
: Protein‐energy malnutrition remains an important underlying cause of death among preschool children in Pakistan. The present study aimed to estimate the prevalence of stunting and its correlates and to explore the role of sex bias in remote rural villages of south Pakistan.

Methods
: We selected 1878 children less than 3 years of age through stratified random sampling from 64 villages having the number of children enrolled proportionate to the size of each village, in rural Sindh, Pakistan. Trained investigators completed child physical measurements and a maternal interview. The Z‐scores for the distribution of height‐for‐age (stunting) and weight‐for‐height (wasting) were estimated relative to those of the National Center for Health Statistics/Center for Disease Control (NCHS/CDC) reference population.

Results
: A total of 483 (26%) of the 1878 children were wasted, 977 (55%) were stunted and 259 (15%) were both wasted and stunted. Mothers who were illiterate were more likely to have children who were stunted (odds ratio (OR) = 1.27, 95% confidence interval (CI) 1.11–1.61). Fathers who earn less than Rs. 1000 (US $20) per month (OR = 1.35, 95% CI 1.12–1.66) were more likely to have children who were stunted. Children living in an overcrowded house were more likely to be stunted (OR = 1.44, 95% CI 1.18–1.75). Male children compared to females were equally likely to be stunted (57 vs 55%, OR 1.03, 95% CI 0.86–1.25).

Conclusions
: In this region of lower Sindh, stunting is more common than wasting. Female illiteracy, poor household income and overcrowding are important risk factors for stunting. The prevalent belief that in rural Pakistan, parents pay attention to feeding male children at the cost of female children is not proven by these data.
Endothelin‐1 in children with acute poststreptococcal glomerulonephritis and hypertension
Authors: NICOLAIDOU POLYXENI , GEORGOULI HELEN , MATSINOS YIANNIS , PSYCHOU FOTINI , MESSARITAKI ANNA , GOURGIOTIS DIMITRIS , ZEIS PETROS
Published: May 2004

Abstract

Background
: Endothelin‐1 (ET‐1), the most potent vasoconstrictor peptide, is known to play a role in arterial hypertension. In patients with acute poststreptococcal glomerulonephritis (APSGN) an increase in the production of ET‐1 is suspected due to damaged endothelium, platelet activation and increased thrombin production in the glomeruli. The aim of the present study was to investigate whether the levels of plasma ET‐1 are elevated in children with APSGN. Furthermore, we examined the association between plasma ET‐1 levels and blood pressure levels in the same children.

Methods
: We studied 18 children (14 boys) with APSGN (mean age 7.44~2.82 years). Fourteen healthy children served as controls. The following parameters were evaluated: plasma ET‐1, plasma atrial natriuretic peptide (ANP), plasma renin (Rn), serum aldosterone (Aldo), creatinine clearance (Ccr) and fractional excretion of sodium (FENa).

Results
: The mean plasma ET‐1 concentrations were higher in patients with APSGN (3.39~1.86 pg/mL) compared to controls (1.40~0.15 pg/mL; P=0.0001). Patients with APSGN also had higher plasma ANP concentrations (41.67~27.99 pg/mL) than the controls (22.80~4.24 pg/mL; P=0.011). Plasma Rn concentrations were lower in patients (24.54~16.34 μU/mL) compared to controls (56.76~32.36 μU/mL; P=0.027). A positive correlation was found between ET‐1 plasma concentrations and the height of systolic or diastolic blood pressure (r=0.57, P=0.013 and r=0.53, P=0.023, respectively).

Conclusions
: Our results suggest that increased plasma ET‐1 concentrations may play an important role in the pathogenesis of hypertension in children with acute poststreptococcal glomerulonephritis.
Transcatheter occlusion of patent ductus arteriosus using tornado platinum coils
Authors: SUDA KENJI , MATSUMURA MASAHIKO
Published: May 2004

Abstract

Background
: The purpose of the present study was to develop a method to occlude a patent ductus arteriosus (PDA) using a tornado platinum coil, which is compatible with magnetic fields.

Methods
: Twelve patients with a PDA (5 boys and 7 girls; 0.6 to 7 yrs; 6.5 to 22.1 kg) were enrolled. The minimum size of the PDA ranged from 0.2 mm to 3.6 mm. Either the anterograde or retrograde method was applied using a retrievable system that consisted of a 5‐Fr multipurpose catheter and a 3‐Fr bioptome. Three to 3.5 loops of the larger end of a tornado platinum coil were placed in the aortic ampulla and the remaining 0.5–1.0 loop of the smaller end of the coil was placed in the main pulmonary artery.

Results
: In 11 patients with minimum size of PDA ≤ 2.8 mm, the PDA was successfully occluded using one to five tornado platinum coils and, in 10 of 11 patients, an echocardiogram confirmed complete occlusion up to 6 months after the procedures. In the remaining patient with a relatively large PDA (3.6 mm), the PDA could not be occluded because of instability of the coils.

Conclusions
: It is feasible to occlude a relatively small PDA (≤ 2.8 mm) using tornado platinum coils, but further study is warranted to evaluate the safety and efficacy of this method.
Hypophosphatemia in juvenile patients with systemic lupus erythematosus
Authors: FUJIWARA IKUMA , OGAWA EISHIN , KONDO YOSHIAKI , OHURA TOSHIHIRO , IINUMA KAZUIE
Published: May 2004

Abstract

Background
: Hypophosphatemia is observed in both genetic diseases and acquired disorders, although it has never been described in systemic lupus erythematosus (SLE). The present study reports hypophosphatemia observed in patients with SLE, and investigates whether serum phosphorus (P) concentration is associated with disease activity and some cytokines.

Methods
: Six girls with SLE (age 10 to 16 years) and seven age‐matched controls were studied. Relationships between serum P and parameters that represented disease activity were evaluated. Interleukin (IL) 6 and tumor necrosis factor α (TNF‐α) levels were measured by enzyme‐linked immunosorbent assay (ELISA).

Results
: Two of the patients with SLE developed marked hypophosphatemia during active disease. Their serum P significantly correlated positively with serum complements, red blood cell (RBC) and platelet counts, and negatively with anti‐double‐stranded DNA antibody (dsDNAab). Three of the remaining four patients showed the same trend, in which their serum P significantly correlated with RBC, platelets, dsDNAab and/or serum complement concentrations. Serum and urinary IL‐6 and serum TNF‐α were higher in active SLE patients than those with inactive disease or in the control group. In addition, the concentrations of these cytokines significantly correlated inversely with serum P. Renal tubular reabsorption of P was significantly lower in patients with active disease both with and without lupus nephritis.

Conclusions
: Hypophosphatemia may be another sign of juvenile SLE, and serum P may represent disease activity. Both TNF‐α and IL‐6 may be related to hypophosphatemia in patients with SLE. Waste of P from renal tubules may be a possible mechanism of hypophosphatemia in SLE.
Influence of heart surgery on magnesium concentrations in pediatric patients
Authors: HOSHINO KENJI , OGAWA KIYOSHI , HISHITANI TAKASHI , KITAZAWA REIKO
Published: May 2004

Abstract

Background
: There have been only a few investigations into the effects of cardiopulmonary bypass (CPB) on the magnesium (Mg) concentrations in pediatric patients. The purpose of the present study was to compare the postoperative Mg concentrations and their recovery time to pre‐surgical values in pediatric patients undergoing CPB for surgical repair of congenital heart disease. The incidence of dysrhythmia was also determined.

Methods
: Twenty‐seven pediatric patients undergoing open‐heart surgery with CPB were enrolled in this study. Controls were 23 pediatric patients undergoing palliative surgery without CPB. Serum Mg (SMg) concentrations and ionized Mg (iMg) concentrations were measured at four sample points: 24 h before the surgery, immediately after the surgery, 24 h after the surgery and 48 h after the surgery.

Results
: Serum Mg and iMg concentrations were significantly decreased after open‐heart surgery. Immediately after the surgery, the mean SMg concentration was 64.1% and the mean iMg concentration was 68.8% of the pre‐surgical values. The concentration of iMg showed quicker recovery than that of SMg, and returned to normal range 48 h after surgery. However, SMg and iMg concentrations after palliative surgery did not show significant differences from the pre‐surgical values. The incidence of dysrhythmia was almost the same between the two groups; dysrhythmia was observed in two patients in the open‐heart surgery group and in three patients in the palliative surgery group.

Conclusions
: Mg concentrations showed significant decrease after CPB; however, they showed quick recovery and did not increase the incidence of dysrhythmia in pediatric patients.
Biochemical and molecular characterization of mutant hexosaminidase A in a Turkish family
Authors: SİNİCİ İNCİLAY , ÖZKARA H.ASUMAN , TOPÇU MERAL , CİLİV GÖNENÇ
Published: May 2004

Abstract

Background
: Tay‐Sachs disease is a form of monosialoganglioside triaose (GM2) gangliosidosis that results from the mutations in the alpha‐subunit gene of hexosaminidase A. In the B1 variant, the active site of the alpha‐subunit of the enzyme is thought to be affected. In the present study, a patient who had previously been diagnosed as a B1 variant is further analyzed. The patient's parents and brother were also analyzed.

Methods
: Single‐stranded conformational polymorphism (SSCP) and DNA sequencing analysis were conducted in all cases. In addition, hexosaminidase A (Hex A) was isolated from leukocyte homogenates of the patient's parents and brother using DE 52 ion‐exchange chromatography, and thermostability analyses of the isolated enzymes were performed.

Results
: Hexosaminidase A of the parents was found to be more thermostable than normal Hex A. DNA sequencing analysis revealed a 12‐bp deletion mutation in exon 10 of the Hex A gene. The patient was a homozygote and the parents were heterozygotes for the mutation, which could also be observed at the DNA double strands by SSCP analysis. These deleted bases are located within the catalytic domain of the alpha‐subunit.

Conclusion
: The 12‐bp deletion mutation in exon 10 of Hex A is responsible for the increased thermostability of the enzyme. Considering this mutation has previously been found in a Turkish Tay‐Sachs patient, the patient in the present study may have another mutation on the Hex B gene that causes decreased thermostability of the enzyme. Thermal inactivation assay may not be sufficient for a correct diagnosis in such unusual cases.
Comparison of different therapy approaches in children with Down syndrome
Authors: UYANİK MINE , BUMIN GONCA , KAYİHAN HÜLYA
Published: May 2004

AbstractBackground: Children with Down syndrome have sensory integrative dysfunction as a result of limited sensory experience from lack of normal motor control. The aim of the present study was to compare the effects of sensory integrative therapy alone, vestibular stimulation in addition to sensory integrative therapy and neurodevelopmental therapy, on children with Down syndrome.

Methods: The present study was carried out at the Occupational Therapy Unit, School of Physical Therapy and Rehabilitation of Hacettepe University. Forty‐five children who were diagnosed as having Down syndrome by the Departments of Paediatric Neurology and Medical Genetics at Hacettepe University were assessed and randomly divided into three groups. Sensory integrative therapy was given to the first group (n=15), vestibular stimulation in addition sensory integrative therapy was given to the second group (n=15) and neurodevelopmental therapy was given to the third group (n=15). All children were evaluated with Ayres Southern California Sensory Integration Test, Pivot Prone Test, Gravitational Insecurity Test and Pegboard Test. The hypotonicity of extensor muscles, joint stability, automatic movement reactions and locomotor skills were tested. Treatment programs were 1.5 h per session, 3 days per week for 3 months.

Results: When these groups were compared, statistically significant differences were found in subjects’ performance of balance on right foot‐eyes open, pivot prone position–quality score and locomotor skills‐front tests (P<0.05). There were no significant differences in the other tests (P>0.05).

Conclusion: The results of the present study showed that sensory integration, vestibular stimulation and neurodevelopmental therapy were effective in children with Down syndrome. It was concluded that when designing rehabilitation programs for children with Down syndrome, all treatment methods should be applied in combination, and should support each other according to the individual needs of the child.
Intravenous cyclophosphamide is the drug of choice for steroid dependent nephrotic syndrome
Authors: BİRCAN ZELAL , KARA BÜLENT
Published: May 2004

Abstract

Background
: Steroid dependency is a major problem seen after therapy for idiopathic nephrotic syndrome in childhood. Although there is consensus about the usage of cyclophosphamide (CYC) in frequent relapsers, there is still a controversy concerning its usage in steroid‐dependent nephrotic syndrome (SDNS).

Methods
: In the present study, nineteen children with SDNS were treated with CYC: ten via the intravenous (i.v.) route, and nine via the oral route. Remission was then maintained with prednisolone. Oral CYC therapy consisted of CYC at a dose of 2 mg/kg per day for 12 weeks. Intravenous (i.v.) CYC therapy consisted of CYC 500 mg/m2 per month (with intravenous 3500 cc/m2 per 24 h one‐third saline hydration) for 6 months.

Results
: The cumulative dose of CYC was 168 mg/kg in the oral group and 132 mg/kg in the IV group. Daily oral CYC dose was 1.96~0.31 mg/kg, whereas i.v. CYC dose was 0.73~0.03 mg/kg. Long‐term complications and side‐effects such as alopecia, infection and hemorrhagic cystitis were not observed in the i.v. CYC treated group. In the long term, the dosage of prednisolone that held remission after CYC, the annualized relapse rates and the subsequent relapse time were significantly better in the i.v. CYC group, and the number of patients in remission for 2 years was significantly higher in the i.v. treated group (P<0.05).

Conclusion
: In SDNS, i.v. CYC has a long lasting effect with lower annualized relapse rates and longer subsequent relapse time with a lower steroid dosage required to maintain remission than oral CYC. The results of the present study showed the safety of the i.v. route, and it is the preferable treatment in noncompliant patients for its long lasting remission and simple and inexpensive follow up.
Factors associated with practice of procedures in pediatric‐related areas among certified pediatricians
Authors: UEHARA RITEI , OKAYAMA MASANOBU , KAJII EIJI , NAKAMURA YOSIKAZU , ETO YOSHIKATSU
Published: May 2004

Abstract

Background
: Medical care in pediatric‐related areas in which physicians other than pediatricians, such as surgeons, otolaryngologists, ophthalmologists, orthopedists and dermatologists, can also participate is one of the fields of pediatric primary care. Independent factors associated with the practice of specific procedures in pediatric‐related areas by certified pediatricians in Japan were evaluated.

Methods
: Data were collected from a nationwide survey of 1116 pediatricians who were selected by systematic sampling from the list of certificated members of the Japan Pediatric Society. The survey included questions relating to full‐ or part‐time practice, types of practice setting, practice with or without pediatric subspecialty interest, numbers of procedures performed among 15 procedures in pediatric‐related areas, and attitude toward practice of those procedures.

Results
: Of 79% of respondents, 73% were analyzed (n=810). Among 15 procedures in pediatric‐related areas, seven procedures performed by more than 30% of certificated pediatricians were evaluated. In comparison with certified pediatricians who annually performed three or less procedures (n=410), certified pediatricians who annually performed four or more procedures (n=400) were more likely to be young and male, working full‐time and in a general hospital setting, practicing with a pediatric subspecialty interest. In multiple logistic regression analyses, young age (odds ratio [OR]: 0.8 per 10 years of age; 95% CI: 0.6–0.9), positive attitude toward practice (OR: 1.7; 95% CI: 1.6–1.9), male (OR: 1.7; 95% CI: 1.1–2.5), full‐time practice (OR: 3.2; 95% CI: 1.5–6.9), and practice in general hospital setting (OR: 1.7; 95% CI: 1.2–2.4) were independently associated with more extensive practice of procedures in pediatric‐related areas.

Conclusions
: A positive attitude toward medical care in pediatric‐related areas is one of the most important factors associated with practice of procedures in these areas. An educational strategy for pediatricians to keep their motivation high for improved medical care in these areas should be planned in Japan.
Direct numerical simulation of a transitional temporal mixing layer laden with multicomponent-fuel evaporating drops using continuous thermodynamics
Authors: Le Clercq P. C. , Bellan J.
Published: April 2004

A model of a temporal three-dimensional mixing layer laden with fuel drops of a liquid containing a large number of species is derived. The fuel model is based on continuous thermodynamics, whereby the composition is statistically described through a distribution function parametrized on the species molar weight. The drop temperature is initially lower than that of the carrier gas, leading to drop heat up and evaporation. The model describing the changes in the multicomponent (MC) fuel drop composition and in the gas phase composition due to evaporation encompasses only two more conservation equations when compared with the equivalent single-component (SC) fuel formulation. Single drop results of a MC fuel having a sharply peaked distribution are shown to compare favorably with a validated SC-fuel drop simulation. Then, single drop comparisons are performed between results from MC fuel and a representative SC fuel used as a surrogate of the MC fuel. Further, two mixing layer simulations are conducted with a MC fuel and they are compared to representative SC-fuel simulations conducted elsewhere. Examination of the results shows that although the global layer characteristics are generally similar in the SC and MC situations, the MC layers display a higher momentum-thickness-based Reynolds number at transition. Vorticity analysis shows that the SC layers exhibit larger vortical activity than their MC counterpart. An examination of the drop organization at transition shows more structure and an increased drop-number density for MC simulations in regions of moderate and high strain. These results are primarily attributed to the slower evaporation of MC-fuel drops than of their SC counterpart. This slower evaporation is due to the lower volatility of the higher molar weight species, and also to condensation of already-evaporated species on drops that are transported in regions of different gas composition. The more volatile species released in the gas phase earlier during the drop lifetime reside in the lower stream while intermediary molar weight species, which egress after the drops are entrained in the mixing layer, reside in the mixing layer and form there a very heterogeneous mixture; the heavier species that evaporate later during the drop lifetime tend to reside in regions of high drop number density. This leads to a segregation of species in the gas phase based on the relative evaporation time from the drops. The ensemble-average drop temperature becomes eventually larger/smaller than the initial drop temperature in MC/SC simulations. Neither this species segregation nor the drop temperature variation with respect to the initial temperature or as a function of the mass loading can be captured by the SC-fuel simulations.
Large eddy simulation and experimental measurements of the near-field of a large turbulent helium plume
Authors: DesJardin Paul E. , O’Hern Timothy J. , Tieszen Sheldon R.
Published: April 2004

Large eddy simulations (LES) are conducted of a large, 1 m in diameter, turbulent helium plume. The plume instability modes and flow dynamics are explored as a function of grid resolution with and without the use of subgrid scale (SGS) models. LES results reproduce well-established varicose puffing mode instabilities as well as secondary “finger-like” azimuthal instabilities leading to the breakdown of periodically shed toroidal vortices. Simulation results of time-averaged velocity and concentration fields show excellent agreement with experimental data collected from Sandia’s FLAME facility using particle image velocimetry and planar laser induced fluorescence measurement techniques. For locations very near the base of the plume, i.e., X/Dp<0.5, the LES overpredicts the measured root-mean squared streamwise velocity and concentration and, in addition, is found to be highly sensitive to grid resolution. The cause of these discrepancies is attributed to unresolved buoyancy-induced vorticity generation on resolved scales of fluid motion that is currently not explicitly treated in the SGS turbulence models used for the LES.
Reflection-mode x-ray powder diffraction cell for in situ studies of electrochemical reactions
Authors: Roberts G. A. , Stewart K. D.
Published: April 2004

The design and operation of an electrochemical cell for reflection-mode powder x-ray diffraction experiments are discussed. The cell is designed for the study of electrodes that are used in rechargeable lithium batteries. It is designed for assembly in a glove box so that air-sensitive materials, such as lithium foil electrodes and carbonate-based electrolytes with lithium salts, can be used. The cell uses a beryllium window for x-ray transmission and electrical contact. A simple mechanism for compressing the electrodes is included in the design. Sample results for the cell are shown with a Cu Kα source and a position-sensitive detector.
Identification of budding yeast using a fiber-optic imaging bundle
Authors: Koschwanez John , Holl Mark , Marquardt Brian , Dragavon Joe , Burgess Lloyd , Meldrum Deirdre
Published: April 2004

A successful imaging system has been designed and built for yeast pedigree analysis. The system uses a fiber-optic imaging bundle to recognize single yeast cells. Image processing software has been developed to accurately classify the cells as either budding or not budding a daughter cell. This system is intended to replace the body of a microscope for the detection of budding in a microfluidic system.
Photoconductive generation of short electrical pulses of variable duration using a coplanar waveguide with capacitively coupled ground termination
Authors: Wu Hsiao-Hua , Liu Jer-Liang , Pan Ci-Ling
Published: April 2004

Short electrical pulses with variable duration are generated by optically exciting a coplanar waveguide that is capacitively connected to a ground termination. The underlying concept is based on the superposition of the original pulse and the reflected one with an opposite sign and a variable round trip delay. By sliding the pump beam along the coplanar waveguide, generation of short electrical pulses with different peak voltages, widths, and signs are demonstrated in a laser-diode-based system.
Impact of thermal dependence of elastic constants on surface stress measurements
Authors: Kury Peter , Horn-von Hoegen Michael
Published: April 2004

The accuracy of surface stress data obtained by means of bending sample methods depends on the precise knowledge of the biaxial Youngs modulus E/1−ν which enters as a prefactor in the stress calculation formula of Stoney and describes the stiffness of the sample’s material against biaxial deformation. Room temperature values are commonly used for E/1−ν. However, E/1−ν is significantly temperature dependent. A second order polynomial fit of this dependence is presented for the benefit of future measurements as well as a correction curve for old data.
Low flicker-noise amplifier for 50 Ω sources
Authors: Rubiola Enrico , Lardet-Vieudrin Franck
Published: April 2004

This article analyzes the design of a low-noise amplifier intended as the input front-end for the measurement of the low-frequency components (below 10 Hz) of a 50 Ω source. Low residual flicker is the main desired performance. This feature can only be appreciated if white noise is sufficiently low, and if an appropriate design ensures dc stability. An optimal solution is proposed, in which the low-noise and dc-stability features are achieved at a reasonable complexity. Gain is accurate to more than 100 kHz, which makes the amplifier an appealing external front-end for fast Fourier transform (FFT) analyzers.