bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Respiratory
Mycoplasma pneumoniae
Infection on Allergen-Induced Bronchial Hyperresponsiveness and Lung Inflammation in Mice
Authors: Chu Hong Wei , Honour Joyce M. , Rawlinson Catherine A. , Harbeck Ronald J. , Martin Richard J. 
Published: February 2003

ABSTRACT

Airway mycoplasma infection may be associated with asthma pathophysiology. However, the direct effects of mycoplasma infection on asthma remain unknown. Using a murine allergic-asthma model, we evaluated the effects of different timing of airway
Mycoplasma pneumoniae
infection on bronchial hyperresponsiveness (BHR), lung inflammation, and the protein levels of Th1 (gamma interferon [IFN-γ]) and Th2 (interleukin 4 [IL-4]) cytokines in bronchoalveolar lavage fluid. When mycoplasma infection occurred 3 days before allergen (ovalbumin) sensitization and challenge, the infection reduced the BHR and inflammatory-cell influx into the lung. This was accompanied by a significant induction of Th1 responses (increased IFN-γ and decreased IL-4 production). Conversely, when mycoplasma infection occurred 2 days after allergen sensitization and challenge, the infection initially caused a temporary reduction of BHR and then increased BHR, lung inflammation, and IL-4 levels. Our data suggest that mycoplasma infection could modulate both physiological and immunological responses in the murine asthma model. Our animal models may also provide a new means to understand the role of infection in asthma pathogenesis and give evidence for the asthma hygiene hypothesis.
Role ofPLB1in Pulmonary Inflammation and Cryptococcal Eicosanoid Production
Authors: Noverr Mairi C. , Cox Gary M. , Perfect John R. , Huffnagle Gary B. 
Published: February 2003

ABSTRACTCryptococcal phospholipase (PLB1) is a secreted enzyme with lysophospholipase hydrolase and lysophospholipase transacylase activities. To investigate the role ofPLB1in the evasion of host immune responses, we characterized pulmonary immune responses to the parental (H99), theplb1mutant, and theplb1recreconstituted mutant strains ofCryptococcus neoformansin mice.PLB1was required for virulence during infection acquired via the respiratory tract. Mice infected with either H99 or theplb1recstrain generated a nonprotective inflammatory response with subsequent eosinophilia, while mice infected with theplb1mutant generated a protective immune response that controlled the infection. BecausePLB1is believed to facilitate virulence through host cell lysis, we examined the interaction of these strains with macrophages. Theplb1recmutant exhibited decreased survival during coculture with macrophages. One factor which may be involved in the survival of yeast in the presence of macrophages is fungal eicosanoid production. Host eicosanoids have been shown to down-modulate macrophage functions.plb1exhibited a defect in eicosanoid production derived from exogenous arachidonoyl-phosphatidylcholine, suggesting thatPLB1is required for the release of arachidonic acid from phospholipids. These data suggest that cryptococcalPLB1may act as a virulence factor by enhancing the ability to survive macrophage antifungal defenses, possibly by facilitating fungal eicosanoid production.
The Zinc-Dependent Major Histocompatibility Complex Class II Binding Site of Streptococcal Pyrogenic Exotoxin C Is Critical for Maximal Superantigen Function and Toxic Activity
Authors: Tripp Timothy J. , McCormick John K. , Webb Jennifer M. , Schlievert Patrick M. 
Published: February 2003

ABSTRACT
The cocrystal structure of streptococcal pyrogenic exotoxin C (SPE C) with HLA-DR2a (DRA*0101,DRB5*0101) revealed a zinc-dependent interaction site through residues 167, 201, and 203 on SPE C and residue 81 on the β-chain of HLA-DR2a (DRA*0101,DRB5*0101). Mutation of these SPE C residues resulted in dramatically reduced biological activities. Thus, the zinc-dependent major histocompatibility complex II binding site is critical for maximal biological function of SPE C.
Role of Interleukin-6 in the Control of Acute and Chronic
Giardia lamblia
Infections in Mice
Authors: Zhou Ping , Li Erqiu , Zhu Nannan , Robertson Jason , Nash Theodore , Singer Steven M. 
Published: February 2003

ABSTRACT

In this study, we investigated the role of interleukin-6 (IL-6) in
Giardia lamblia
infections in mice. Elevated IL-6 expression was found in wild-type mice 15 days postinfection. Furthermore, IL-6-deficient mice controlled infections only slowly although normal immunoglobulin A production was observed. Thus, IL-6 is necessary for early control of acute
G. lamblia
infections.
N-Terminal E-Cadherin Peptides Act as Decoy Receptors for
Listeria monocytogenes
Authors: da Silva Tatley Fernanda , Aldwell Frank E. , Dunbier Anita K. , Guilford Parry J. 
Published: February 2003

ABSTRACT

The observation that E-cadherin is the principal epithelial receptor for the bacterial pathogen
Listeria monocytogenes
led us to investigate whether N-terminal fragments of E-cadherin containing the
L. monocytogenes
binding domain could inhibit entry of the bacteria into cultured epithelial cells. Here we demonstrate that a conditioned medium from a gastric cancer cell line (Kato III) that carries a truncating
CDH-1
mutation 3′ of the
L. monocytogenes
binding domain can inhibit the uptake of the bacteria into Caco-2 cells. The inhibitory activity of the Kato III conditioned medium could be mimicked by incubation of the bacteria with a recombinant 26-kDa N-terminal E-cadherin peptide prior to infection. Furthermore, these data suggest that cleavage of the 80-kDa extracellular domain of E-cadherin from the cell surface may provide an innate form of pathogen defense by acting as a decoy receptor for
L. monocytogenes
.
Purification of Fully ActivatedClostridium botulinumSerotype B Toxin for Treatment of Patients with Dystonia
Authors: Arimitsu Hideyuki , Inoue Kaoru , Sakaguchi Yoshihiko , Lee Jaechul , Fujinaga Yukako , Watanabe Toshihiro , Ohyama Tohru , Hirst Robert , Oguma Keiji 
Published: February 2003

ABSTRACTClostridium botulinumserotype B toxins 12S and 16S were separated by using a beta-lactose gel column at pH 6.0; toxin 12S passed through the column, whereas toxin 16S bound to the column and eluted with lactose. The fully activated neurotoxin was obtained by applying the trypsin-treated 16S toxin on the same column at pH 8.0; the neurotoxin passed through the column, whereas remaining nontoxic components bound to the column. The toxicity of this purified fully activated neurotoxin was retained for a long period by addition of albumin in the preparation.
Clostridium difficile
Vaccine and Serum Immunoglobulin G Antibody Response to Toxin A
Authors: Aboudola Samer , Kotloff Karen L. , Kyne Lorraine , Warny Michel , Kelly Eoin C. , Sougioultzis Stavros , Giannasca Paul J. , Monath Thomas P. , Kelly Ciarán P. 
Published: February 2003

ABSTRACT

There is a strong association between serum antibody responses to toxin A and protection against
Clostridium difficile
diarrhea. A parenteral
C. difficile
toxoid vaccine induced very-high-level responses to anti-toxin A immunoglobulin G (IgG) in the sera of healthy volunteers. After vaccination, the concentrations of anti-toxin A IgG in the sera of all 30 recipients exceeded the concentrations that were associated with protection in previous clinical studies. Furthermore, the median concentration of serum anti-toxin A IgG in the test group was 50-fold higher than the previous threshold. These findings support the feasibility of using a vaccine to protect high-risk individuals against
C. difficile
-associated diarrhea and colitis.
Ventilatory control in patients with sleep apnoea and left ventricular dysfunction: comparison of obstructive and central sleep apnoea
Authors: Wilcox I. , McNamara S.G. , Dodd M.J. , Sullivan C.E. 
Published: February 2003

Sleep apnoea is common in patients with heart failure. While most patients have central sleep apnoea (CSA), a minority have obstructive sleep apnoea (OSA). The pathophysiology of CSA is not well understood. We hypothesized that central chemosensitivity would be an important pathophysiological factor in patients with CSA, and not in OSA. The aim of this study was to compare ventilatory responses between patients with CSA and those with OSA.Acute ventilatory responses to eucapnic hypoxia and hyperoxic hypercapnia were measured during wakefulness in 34 patients (33 males and one female, aged 59±8 yrs (mean±sd)), with stable medically-treated left ventricular dysfunction (LVD) and sleep apnoea (18 OSA and 16 CSA).Patients with CSA had a decreased awake end-tidal carbon dioxide tension (4.1± 0.5 kPa), increased ventilatory response to carbon dioxide (0.65±0.43 L·min-1·kPaPCO2-1), and eucapnic hypoxic responses in the normal range (0.6±0.4 L·min-1/% fall in arterial oxygen saturation (Sa,O2)). In contrast, patients with OSA had normal endtidal carbon dioxide tension (4.9±0.5 kPa), and normal ventilatory responses to hypercapnia (0.29±0.16 L·min-1·kPaPCO2-1) and hypoxia (0.5±0.5 L·min-1/% fall inSa,O2).These findings suggest that augmented chemosensitivity to hypercapnia may be an important factor in the pathophysiology of central sleep apnoea in patients with heart failure.
RE: An alternate characterization of hazard in occupational epidemiology: Years of life lost per years worked. Am J Ind Med 42:1–10, 2002
Authors: Morfeld Peter 
Published: February 2003

AbstractTo the Editor:Park et al. [2002] proposed an alternate characterization of hazard in occupational epidemiology by estimating the excess years of life lost. Roughly speaking, they used an approach based on estimated numbers of excess cases among the exposed multiplied by the potential life expectancy of these cases at their age of death. Although I agree with Park et al. that occupational epidemiology should better report failure time statistics as effect measures rather than risk statistics alone [cmp. Greenland and Robins, 1988], I have to point out, with apologies, that the approach chosen by Park et al. [2002] appears to be potentially biased. A simple example based on counterfactual thinking [Maldonado and Greenland, 2002] may help to demonstrate the problems involved.
Long bone articular and diaphyseal structure in old world monkeys and apes. I: Locomotor effects
Authors: Ruff Christopher B. 
Published: February 2003

AbstractThe relationship between locomotor behavior and long bone structural proportions is examined in 179 individuals and 13 species of hominoids and cercopithecoids. Articular surface areas, estimated from linear caliper measurements, and diaphyseal section moduli (strengths), determined from CT scans, were obtained for the femur, tibia, humerus, radius, and ulna. Both within‐bone (articular to shaft) and between‐bone (forelimb to hindlimb) proportions were calculated and compared between taxa. It was hypothesized that: 1) species emphasizing slow, cautious movement and/or more varied limb positioning (i.e., greater joint excursion) would exhibit larger articular to cross‐sectional shaft proportions, and 2) species with more forelimb suspensory behavior would have relatively stronger/larger forelimbs, while those with more leaping would have relatively stronger/larger hindlimbs. The results of the analysis generally confirm both hypotheses. Several partial exceptions can be explained on the basis of more detailed structural‐functional considerations. Associations between locomotion and structural proportions can be demonstrated both across major groupings (hominoids and cercopithecoids) and between relatively closely related taxa, e.g., mountain and lowland gorillas, siamangs and gibbons, and Trachypithecus and other colobines. Furthermore, structure and function do not always covary with taxonomy. For example, compared to cercopithecoids, mountain gorillas have relatively larger joints, like other hominoids, but do not have relatively stronger forelimbs, unlike other hominoids. This is consistent with a locomotor repertoire emphasizing relatively slow movement but with very little forelimb suspension. Proportions of Proconsul nyanzae, Proconsul heseloni, Morotopithecus bishopi, and Theropithecus oswaldi are compared with modern distributions to illustrate the application of the techniques to fossil taxa. Am J Phys Anthropol 119:305–342, 2002. © 2002 Wiley‐Liss, Inc.
Compatibilization and property characterization of polycarbonate/polyurethane polymeric alloys
Authors: Archondouli P. S. , Kallitsis J. K. , Kalfoglou N. K. 
Published: February 2003

AbstractPolymeric alloys of bisphenol A polycarbonate and a polyester‐type polyurethane were prepared over a complete composition range through melt mixing. The blends were characterized with optical and scanning electron microscopy, tensile testing, dynamic mechanical analysis, thermal analysis (differential scanning calorimetry and thermogravimetric analysis), and spectroscopic techniques (Fourier transform infrared and 1H‐NMR). A morphology examination revealed good component dispersion with 30 wt % polyurethane or less and strong interface adhesion. Dynamic mechanical analysis indicated partial component miscibility and tensile testing mechanical behavior typical of a polymeric alloy. Overall, the degree of compatibilization obtained with polycarbonate was lower than that observed previously with poly(ethylene terephthalate) or poly(butylene terephthalate). This was attributed to the lower reactivity of the aromatic OH of polycarbonate toward the isocyanate groups of polyurethane and the thermal instability of the copolymer–compatibilizer formed. Experimental evidence for the formation of the latter was provided by 1H‐NMR and dynamic mechanical analysis of selectively leached blends and by quantitative analysis results for the extraction experiments. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 612–626, 2003
Study on kinetic of natural rubber vulcanization by using vulcameter
Authors: Wang Ping‐yue , Qian Hong‐lian , Yu He‐ping , Chen Jin 
Published: February 2003

AbstractThe velocity of vulcameter torque change during the vulcanization of natural rubber consists of two increasing and decreasing stages. The vulcanization process in the stage of velocity increasing is not a simple reaction, and can be expressed in an equation of ln(MH − Mt) = lnA − K1(t − t0)α, which is different from the famous equation of Vut = − (aK3/K4)ln[(K2eK1t − K1eK2t)/(K2 − K1)] deduced by Coran, the value of K11/α in the former can be used as a rate constant to calculate the value of activation energy (E1) according to the Arrhenius equation. The vulcanization process in the stage of velocity decreasing consists of two first‐order reactions, and can be expressed in a kinetic equation of ln(MH − Mt) = lnB − K(t − tdis). The time (tp) at which the torque change reaches to the maximum velocity (Vm) is corresponding to the time (tdis) suggested by Coran. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 680–684, 2003
Mathematical model of charge and density distributions in interfacial polymerization of thin films
Authors: Freger V. , Srebnik S. 
Published: February 2003

AbstractA general model for interfacial polymerization is proposed and solved numerically. The model takes into account diffusion and reaction of monomers, presence of unreacted functional groups on the growing polymer, and solubility effects. The formation of a polyamide film in composite separation membranes is taken as an example. The evolution of the concentrations of the polymer and unreacted moieties are followed explicitly, thus enabling the calculations of the limiting thickness and the asymmetric distribution of density and charge in the resulting film. Such knowledge is important for the prediction of rejection and transport properties of the film. The effects of reaction kinetics, monomer concentrations, and hydrodynamic conditions on the properties of the film are analyzed, and a number of analytical correlations are developed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1162–1169, 2003
Preparation and metal ion adsorption properties of the resin containing sulfonic acid groups
Authors: Rivas Bernabé L. , Ruf Beatriz 
Published: February 2003

AbstractIn this study, we explored a new ion exchange material synthesized by radical polymerization of styrene and 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid by using 2,2′‐azo‐isobutyronitrile (1 mol %) and divinylbenzene (0.5 mol %) as initiator and crosslinking reagents, respectively. The resin was obtained from a large excess (90%) of styrene in the feed. The yield was 72.3%. The resin was completely insoluble in water and characterized by elemental analysis, FTIR spectroscopy, scanning electron microscopy, and thermal analysis. The metal ion retention capability was investigated for Ag(I), Hg(II), Cd(II), Zn(II), Pb(II), and Cr(III). The effect of pH, time, and resin/metal ion mol ratio on the metal ion retention was studied. Selectivity of the resins from a mixture of metal ions and the maximum retention capacity at optimum pH were also determined. The recovery of the resin by using 1 and 4 M HClO4 and HNO3 demonstrated that it is possible to recover the resin above 80%. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1230–1235, 2003
Release of ibuprofen from poly(ε‐caprolactone‐co‐D,L‐lactide) and simulation of the release
Authors: Ahola Niina , Rich Jaana , Karjalainen Teija , Seppälä Jukka 
Published: February 2003

AbstractA study was made of the effects of the initial ibuprofen load and of the specimen shape on the release of ibuprofen from poly(ε‐caprolactone‐co‐D,L‐lactide). The mol ratio of the comonomers in the copolymer was 96/4 (caprolactone to lactide) and the experiments were conducted at 37°C in vitro. The results showed that release of ibuprofen is fast and that the rate and profile of the release vary with both the initial load of ibuprofen and the shape of the specimen. The rate of ibuprofen release increases with the initial load and with the surface area‐to‐volume ratio of the specimen, obeying Fickian diffusion. The experimental findings were compared with the results of a mathematical simulation model based on the finite‐difference method. Diffusion parameters needed for the simulation were determined from a separately conducted set of experiments using various methods. For the most part, the results of the simulations and the experiments were in good agreement. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1279–1288, 2003
Lesion progression with time and the effect of vascular occlusion following radiofrequency ablation of the liver
Authors: Wiersinga W J , Jansen M C , Straatsburg I H , Davids P H , Klaase J M , Gouma D J , van Gulik T M 
Published: February 2003

Abstract

Background
The effectiveness of radiofrequency ablation (RFA) under selective vascular occlusion and its effects on architecture and viability of normal liver parenchyma was studied in a porcine model.

Methods
RFA was applied in the liver under general anaesthesia in 18 pigs. Six animals were killed immediately after the procedure and 12 at 24 h. RFA was performed sequentially under four conditions: (1) without vascular occlusion, (2) during occlusion of the hepatic artery, (3) during occlusion of the portal vein and (4) during occlusion of the hepatic artery and portal vein. Liver biopsies from the treated area were stained for conventional histological examination, reduced nicotinamide adenine dinucleotide diaphorase and 5′-nucleotidase activity.

Results
Vascular occlusion significantly increased the size of the coagulation centre after RFA. Combined portal venous and arterial occlusion had no additional effect on lesion size compared with venous or arterial occlusion alone. After 24 h, deterioration of viability was observed in the parenchyma up to 3 cm from the coagulated area.

Conclusion
The efficacy of RFA in liver increases with occlusion of the portal vein or hepatic artery. The extent of secondary heat-induced necrosis in liver parenchyma should be considered for determination of the final size of the ablated area.
Prognostic factors influencing surgical management and outcome of gastrointestinal stromal tumours
Authors: Langer C , Gunawan B , Schüler P , Huber W , Füzesi L , Becker H 
Published: February 2003

Abstract

Background
The purpose of this study was to review surgical experience with gastrointestinal stromal tumours (GISTs) at a single tertiary university hospital, and to identify morphological and genetic prognostic markers of tumour progression.

Methods
Forty-eight GISTs from 39 patients were reviewed retrospectively. The prognostic significance of DNA copy number changes, measured by comparative genomic hybridization (CGH), and morphological markers in low-risk and high-risk tumours were investigated.

Results
Significantly more patients died from disease after incomplete tumour resection than after complete primary resection (P = 0·020). Tumour size of 5 cm or greater, mitotic count of 2 or more, and proliferative activity greater than 10 per cent were significantly associated with a shorter recurrence-free survival (P = 0·020, P = 0·001 and P = 0·002 respectively). Patients with low-risk tumours had a significantly better outcome than those with high-risk GISTs, both in terms of overall and recurrence-free survival (P ≤ 0·001). CGH performed on 16 tumours revealed fewer DNA sequence copy number changes in low-risk than in high-risk GISTs. Non-progressive GISTs contained significantly fewer genetic alterations than recurrent or metastatic tumours (P &lt; 0·001). Only tumours with more than five changes showed disease progression.

Conclusion
Complete surgical resection is the most important means of cure for GISTs. DNA copy number changes are related to the behaviour of these tumours and may serve as additional prognostic markers.