bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human leucocyte antigen determinants of susceptibility to Barrett's oesophagus in Asians – a preliminary study
Authors: Rajendra S. , Ackroyd R. , Murad S. , Mohan C. , Ho J. J. , Goh K. L. , Azrena A. , Too C. L. 
Published: June 2005

SummaryBackground : Characteristic immune profiles have been demonstrated in gastro‐oesophageal reflux disease. However, the genetic basis of gastro‐oesophageal reflux disease remains unclear.Aim : To investigate whether certain human leucocyte antigen genes are associated with Barrett's oesophagus.Methods : Asian patients of Malay, Chinese and Indian descent with Barrett's oesophagus (n = 59) and those without reflux symptoms and a normal oesophagus (n =60) were recruited prospectively using endoscopic and histopathological criteria. Human leucocyte antigen class I and II typing was performed using a polymerase chain reaction sequence‐specific primers method.Results : The HLA‐B7 allele was present in 17% (10 of 59) of patients with Barrett's oesophagus when compared with 0% (zero of 60) of controls [P = 0.0006, corrected P = 0.0171, OR = 25.67]. Subgroup analysis revealed that the HLA‐B7 allele was confined almost exclusively to Indians with Barrett's oesophagus, 43% (nine of 21) vs. 0% (zero of 19) Indian controls (P = 0.0014, corrected P = 0.0406, OR = 29.64). No class II associations, protective human leucocyte antigens or extended haplotypes for disease susceptibility were identified.Conclusions : Barrett's oesophagus in Asians, particularly Indians, is strongly positively associated with HLA‐B7; reinforcing a genetic component to gastro‐oesophageal reflux disease. A larger sample size and different ethnic populations should be genotyped to further confirm this association and identify possible additional risk factors in the human leucocyte antigen locus.
Changes in different regions of hepatitis B virus gene in hepatitis B ‘e’ antigen‐negative patients with chronic hepatitis B: the effect of long‐term lamivudine therapy
Authors: Buti M. , Jardi R. , Rodriguez‐Frias F. , Valdes A. , Schaper M. , Esteban R. , Guardia J. 
Published: June 2005

SummaryBackground : Lamivudine therapy for chronic hepatitis B has been associated with changes in different regions of the hepatitis B virus nucleotide sequence.Aim : To study changes in the sequences of polymerase and precore/core promoter regions of hepatitis B virus, before and during 5 years of therapy with lamivudine.Methods : Eighty consecutive samples were taken from 10 chronic hepatitis B ‘e’ antigen‐negative patients.Results : Nine patients carried hepatitis B virus precore mutations during the study. Before therapy, wild type was replaced by A1896 in two (20%) cases. During treatment, A1896 reverted transitory to wild type in five cases (50%) and in one case wild type was replaced by A1896. The continuous detection of precore mutations during therapy was associated with a lower response rate.YMDD mutations were observed in nine cases and both, L180M and M204V/I mutations were simultaneously detected in six cases. About 75% of the patients with M204V mutations were responders and none with M204I or mixed pattern sustained response.Conclusion : Hepatitis B ‘e’ antigen‐negative patients exhibit changes in the precore regions both spontaneously and under lamivudine therapy, the transitory reversion to wild type being most frequently witnessed. Patients carrying M204V mutations are more likely to respond to therapy. If, in further studies, these results are confirmed some patients with YMDD mutations could benefit from prolonging the duration of lamivudine therapy.
A study on spot heating induced fatigue crack growth retardation
Authors: RAY P. K. , RAY P. K. , VERMA B. B. 
Published: June 2005

ABSTRACTThe propagation of a growing fatigue crack can be effectively retarded by heating a spot near the crack tip (under zero stress condition). Spot heating to a subcritical temperature and at a precise location modifies the crack growth behaviour in a way, more or less, similar to specimens subjected to an overload spike. It is observed that the magnitude of spot heating induced crack growth retardation increases with increase in spot temperature. It is also observed that the crack growth behaviour is influenced by the position of the heating spot and there exists an optimum position of hot spot that produces maximum retardation in fatigue crack growth rate. The plastic zone length due to spot heating has been estimated using experimental data. It is found that the plastic zone length due to spot heating increases exponentially with increase in spot temperature. The Wheeler model for crack growth retardation has been modified by introducing a plastic zone correction factor λ. The values of λ and the shaping exponent, m, in the Wheeler model have been obtained for different spot heating temperatures.
Fracture of plasma‐sprayed thick thermal barrier coatings under multiaxial stress states
Authors: GAO H. , SOCIE D. F. 
Published: June 2005

ABSTRACTFailure behaviour of free‐standing plasma‐sprayed coatings was investigated under combined axial and shear loading. Thin‐walled tubular specimens were loaded with various combinations of tension/compression and torsion. This allows the failure surface to be established for loading situations where the two principal stresses are of opposite signs. Specimens failed in one of the two modes, a tensile failure perpendicular to the maximum principal stress or a compression shear failure through the thickness. Failure data were adequately described by the maximum principal stress theory. Stress–strain curves fall within a single scatter band depending on the failure mode. In situ deformation tests showed that the mechanism was microcrack closing and sliding in compression and microcrack opening, coalescence and the development of new microcracks in tension.
Population pharmacokinetic analysis of indinavir in HIV‐infected patient treated with a stable antiretroviral therapy
Authors: Brendel Karl , Legrand Mayeule , Taburet Anne‐Marie , Baron Gabriel , Goujard Cécile , Mentré France ,   the Cophar 1‐ANRS 102 Trial Group
Published: June 2005

AbstractThe objectives of this study were to build a population pharmacokinetic model that describe plasma concentrations of indinavir in human immunodeficiency virus (HIV)‐infected patients with sustained virological response under a stable antiretroviral combination, and to characterize the effect of covariates and comedications on indinavir pharmacokinetics. Data were obtained from 45 patients who received different dosages of indinavir: either indinavir alone t.i.d. (mostly 800 mg), either indinavir b.i.d. (mostly 800 mg) with a booster dose of 100 mg of ritonavir. Patients were required to have a baseline plasma HIV RNA <200 copies/mL and to have unchanged antiretroviral treatment for 6 months. Indinavir concentrations were measured at a first visit (one sample before drug administration and five after) and at a second visit 3 months later (before and 1 or 3 h after drug administration). A one‐compartment model with first‐order absorption and first‐order elimination best described indinavir pharmacokinetics. For patients treated with indinavir alone, absorption rate constant was estimated to be 0.43/h, and oral clearance Cl/F was 33 L/h. For patients treated with indinavir plus ritonavir these estimates were 0.25/h and 19 L/h, respectively. Cl/F was found to increase by 1.45‐fold in men and by 1.18‐fold in patients also receiving zidovudine. Oral volume of distribution (V/F) was 24 L. The inter‐individual and intra‐individual variability were 117 and 205% for V/F, 42 and 58% for Cl/F, respectively. This population analysis in patients with sustained virological response, quantified the effect of ritonavir on the absorption rate constant and on the clearance of indinavir, showed an increase of Cl/F in men and can be used to draw reference curve for therapeutic drug monitoring.
Prostaglandin E synthase in the pathophysiology of arthritis
Authors: Kojima Fumiaki , Kato Soichiro , Kawai Shinichi 
Published: June 2005

AbstractProstaglandin E synthase (PGES) is a recently identified terminal enzyme that acts downstream of cyclooxygenase and catalyzes the conversion of prostaglandin (PG) H2 to PGE2. At least three isozymes have been cloned so far, which are called membrane‐associated PGES (mPGES)‐1, mPGES‐2, and cytosolic PGES. Among them, mPGES‐1 is induced by various inflammatory stimuli in some cells and tissues. Induction of mPGES‐1 in the component of articular tissues of patients with rheumatoid arthritis and osteoarthritis has been demonstrated in vitro. Recent studies using adjuvant induced arthritis model have shown the increase of mPGES‐1 expression resulted in the increase of PGE2 production at the sites of inflammation. In addition, reports of mPGES‐1‐deficient mice clearly suggest the role of mPGES‐1 in the process of chronic inflammation such as collagen‐induced arthritis and collagen antibody induced arthritis in vivo. Thus, recent in vitro and in vivo findings suggest that mPGES‐1 may be a novel therapeutic target for arthritis. This paper introduces recent advances in research about the role of PGES in the pathophysiology of arthritis.
Gefitinib (ZD1839, Iressa®) in non‐small‐cell lung cancer: a review of clinical trials from a daily practice perspective
Authors: Barlési Fabrice , Tchouhadjian Cécile , Doddoli Christophe , Villani Patrick , Greillier Laurent , Kleisbauer Jean‐Pierre , Thomas Pascal , Astoul Philippe 
Published: June 2005

AbstractGefitinib (ZD1839) is the most widely studied targeting agent in the area of non‐small‐cell lung cancer (NSCLC). Gefitinib is an orally active epidermal growth factor receptor (EGFR) tyrosine kinase (TK) inhibitor. In order to assess the role of gefitinib in the management of NSCLC patients, we systematically reviewed published clinical trials from a daily practice perspective. A systematic research was made in the international medical literature. Gefitinib demonstrated a good tolerance and an encouraging efficacy in pretreated NSCLC patients in preclinical studies. These results were then confirmed in two phase II trials (IDEAL 1 and 2) involving more than 400 patients mostly pretreated with a platinum‐containing regimen and docetaxel. All these results were reinforced by those of retrospective studies on patients enrolled in a compassionate use programme. Thus, two phase III trials in chemo‐naive patients were initiated (INTACT 1 and 2). Unfortunately, the use of gefitinib with standard combination chemotherapy provided no survival benefit nor response rate or progression‐free survival improvement over placebo. Furthermore, we also reviewed the results of studies interested in the characterization of predictive clinical or biological markers for response to gefitinib and discussed the results obtained with other EGFR inhibitors. The efficacy of gefitinib in the first‐line setting of each stage of NSCLC has to be further studied through clinical trials. Furthermore, translational studies characterizing the molecular features involved in the response to anti‐EGFR‐targeted therapies are needed.
The implications of P‐glycoprotein in HIV: friend or foe?
Authors: Owen Andrew , Chandler Becky , Back David J. 
Published: June 2005

AbstractP‐glycoprotein (P‐gp), coded by the ABCB1 gene, has a wide tissue distribution. The drug transporter is known to limit the bioavailability of a plethora of drugs and xenobiotics including the human immunodeficiency virus (HIV) protease inhibitors. There remains a considerable degree of debate in the literature with respect to the role of ABCB1 polymorphisms in HIV‐treatment outcome and some studies have also implicated antiretroviral drugs as inducers of P‐gp. Recent evidence indicates a role for P‐gp in the inhibition of viral infectivity and/or release and cellular relationships with other infection‐related proteins (and cholesterol). It is becoming increasingly clear that future studies on P‐gp in HIV should consider both pharmacological and virological issues.
Allergy‐like reactions to iodinated contrast agents. A critical analysis
Authors: Jean‐Marc Idée , Emmanuelle Pinès , Philippe Prigent , Claire Corot 
Published: June 2005

AbstractAllergy‐like reactions may occur following administration of iodinated contrast media (CM), mostly in at‐risk patients (patients with history of previous reaction, history of allergy, co‐treated with interleukin‐2 or beta‐blockers, etc.) but remain generally unpredictable. Severe and fatal reactions are very rare events. All categories of CM may induce such reactions, although first generation (high osmolar CM) have been found to induce a higher rate of adverse events than low osmolar CM. However, no differences were found between the two categories of CM with respect to mortality. Delayed reactions can also occur. There are no differences between the various categories of CM except for non‐ionic dimers, which are more likely to induce such effect. Numerous clinical studies have evaluated the prophylactic value of drugs (mostly antihistamines and corticosteroids). Results are unclear and highly variable. Any prevention depends upon the mechanism involved. However, the mechanism of CM‐induced allergy‐like reaction remains disputed. Relatively recent data revived the hypothesis of a type‐I hypersensitivity mechanism. Positive skin tests to CM have been reported. However, the affinity of IgE towards CM has been found to be very low in the only study which actually evaluated it. Other pathophysiological mechanisms (involving direct secretory effects on mast cells or basophils, or activation of the complement system associated or not with the plasma contact system) are also much debated. Anaphylaxis and anaphylactoid reactions are, in the end, clinically undistinguishable.
Effects of melatonin and caffeic acid phenethyl ester on testicular injury induced by myocardial ischemia/reperfusion in rats
Authors: Eşrefoğlu Mukaddes , Gül Mehmet , Parlakpinar Hakan , Acet Ahmet 
Published: June 2005

AbstractExperimental studies indicate that ischemia/reperfusion (I/R) causes remote organ injury although the molecular mechanism has not been clearly defined. In this report, the role of oxidative injury on testicular damage following myocardial I/R injury and the effects of antioxidant agents, melatonin and caffeic acid phenethyl ester (CAPE), on testicular injury were investigated. As far as we know, this is the first report demonstrating that myocardial I/R induces damage to the testes. Thirty‐two male Wistar rats were randomly divided into four groups: sham operation (SO), I/R + vehicle, I/R + melatonin, and I/R + caffeic acid phenethyl ester. To produce cardiac damage, the left main coronary artery was occluded for 30 min, followed by 120 min reperfusion, in anesthetized rats. Serum nitric oxide (NO) and malondialdehyde (MDA) levels and morphological changes were examined. I/R was accompanied by a significant increase in serum MDA and NO levels, whereas, melatonin and CAPE administration significantly reduced these values. Melatonin was more efficient in reducing MDA levels than CAPE (P < 0.05). I/R induced myocardial damage, manifested as the histopathological evidence of intracellular vacuolization, interstitial edema, neutrophil infiltration and coagulative necrosis. I/R + vehicle group showed many histological alterations such as focal tubular atrophy, and degeneration and disorganization of the seminiferous epithelium in testes. The number of atrophic tubules and degenerating cells was significantly higher in I/R + vehicle group than that of SO group. Melatonin and CAPE significantly reduced the number of degenerating cells; additionally, melatonin reduced the number of atrophic tubules (P < 0.05). Our results indicate that myocardial I/R induces severe testicular damage and antioxidant agents, especially melatonin, have protective effects on testicular injury after myocardial I/R. Our data emphasize that oxygen‐based reactants may play a central role in remote organ injury.
Impaired α1‐adrenergic responses in aged rat hearts
Authors: Montagne Olivier , Corvoisier Philippe Le , Guenoun Thierry , Laplace Monique , Crozatier Bertrand 
Published: June 2005

AbstractTo determine age‐related changes in the cardiac effect of α1‐adrenergic stimulation, both cardiomyocyte Ca2+‐transient and cardiac protein kinase C (PKC) activity were measured in 3‐month‐ (3MO) and 24‐month‐ (24MO) old Wistar rats. Ca2+ transients obtained under 1 Hz pacing by microfluorimetry of cardiomyocyte loaded with indo‐1 (405/480 nm fluorescence ratio) were compared in control conditions (Kreb's solution alone) and after α1‐adrenergic stimulation (phenylephrine or cirazoline, an α1‐specific agonist). PKC activity and PKC translocation index (particulate/total activity) were also assayed before and after α1‐adrenergic stimulation. In 3MO, cirazoline induced a significant increase in Ca2+ transient for a 10−9 m concentration which returned to control values for larger concentrations. In contrast, in 24MO, we observed a constant negative effect of cirazoline on the Ca2+ transient with a significant decrease at 10−6 m compared with both baseline and Kreb's solution. Preliminary experiments showed that, in a dose–response curve to phenylephrine, the response of Ca2+ transient was maximal at 10−7 m. This concentration induced a significant increase in Ca2+ transient in 3MO and a significant decrease in 24MO. The same concentration was chosen to perform PKC activity measurements under α1‐adrenergic stimulation. In the basal state, PKC particulate activity was higher in 24MO than that in 3MO but was not different in cytosolic fractions; so that the translocation index was higher in 24MO (P < 0.01). After phenylephrine, a translocation of PKC toward the particulate fraction was observed in 3MO but not in 24MO. In conclusion, cardiac α1‐adrenoceptor response was found to be impaired in aged hearts. The negative effect of α1‐adrenergic stimulation on Ca2+ transient in cardiomyocytes obtained from old rats can be related to an absence of α1‐adrenergic‐induced PKC translocation.
Effects of ouabain on contractions induced by manganese ions in Ca2+‐free, isotonic solutions with varying concentrations of K+ in guinea‐pig taenia coli
Authors: Nasu Tetsuyuki , Takahashi Katsunori 
Published: June 2005

AbstractThe action of ouabain, a cell membrane Na+, K+‐ATPase blocker, on contractions induced by manganese ions (Mn2+) in Ca2+‐free, isotonic solutions with varying concentrations of K+ in the external medium were investigated in order to evaluate the underlying role of external Na+ in Mn2+‐induced contractions in isolated taenia coli of the guinea‐pig. Mn2+ at 5 mm induced greater contractions as external isotonic K+ concentrations progressively increased from 10 to 100 mm. Ouabain (2 × 10−4 m) completely inhibited tension development stimulated by 5 mm Mn2+ in isotonic, 30 mm K+ (96 mm Na+) medium. Whereas, the tension inhibitory effects of ouabain became progressively weaker as isotonic, external K+ concentrations increased to 60 mm, which successively decreased external Na+ concentrations. Eventually, ouabain failed to affect contractions stimulated by Mn2+ in isotonic, 126 mm K+, Na+‐deficient medium. Ouabain caused progressively greater increase in cellular Na+ concentrations as the Na+ concentrations increased in the isotonic, K+ medium. While, pyruvate, which penetrates cell independently of external Na+, reversed the inhibition of tension by ouabain in isotonic, 30 mm K+, Na+‐sufficient (96 mm) medium containing 5 mm Mn2+. These results suggested that Mn2+ induced the contraction, which was maintained by glucose transport depending on external Na+, in the case of Na+‐sufficient medium in K+‐depolarized taenia coli. However, it induced the contraction independent of external Na+, in the case of Na+‐deficient, K+ medium. Ouabain might exhibit greater inhibition of the contraction induced by Mn2+ as the decrease in the Na+ gradient across the cell membranes continues.
Combined Influence of Mass and Thermal Stratification on
Double-Diffusion Non-Darcian Natural Convection From a Wavy Vertical Wall to
Porous Media
Authors: Rathish Kumar B. V. , Shalini  
Published: June 2005

Abstract
In this study we analyze the combined influence of mass and thermal stratification on non-Darcian double-diffusive natural convection from a wavy vertical wall to a porous media. A finite difference scheme based on the Keller box approach is derived for the boundary layer equations resulting from the use of nonsimilarity transformation on the coupled nonlinear partial differential equations. Extensive numerical simulations are carried out to analyze the influence of wave amplitude a, Grashof number Gr*, thermal stratification parameter ST, concentration stratification parameter SC, buoyancy ratio B, and Lewis number Le on the double-diffusive natural convection process. Increasing a and Gr* or decreasing B is seen to favor the heat and mass transport in the porous region thereby reducing the heat and mass fluxes along the vertical heated surface. Increasing ST or decreasing Le leads to an enhanced mass transfer process. Presence of surface waviness brings in a wavy pattern in the local heat and mass fluxes with decreasing magnitudes in the streamwise direction in the presence of stratification terms.
Planar Parameterization for Closed Manifold Genus-g Meshes Using Any Type of Positive Weights
Authors: Steiner D. , Fischer A. 
Published: June 2005

AbstractParameterization of 3D meshes is important for many graphic and CAD applications, in particular for texture mapping, remeshing, and morphing. Current parameterization methods for closed manifold genus-g meshes usually involve cutting the mesh according to the object generators, adjusting the resulting boundary and then determining the 2D parameterization coordinates of the mesh vertices, such that the flattened triangles are not too distorted and do not overlap. Unfortunately, adjusting the boundary distorts the resulting parameterization, especially near the boundary. To overcome this problem for genus-g meshes we first address the special case of closed manifold genus-1 meshes by presenting cyclic boundary constraints. Then, we expand the idea of cyclic boundary constraints by presenting a new generalized method developed for planar parameterization of closed manifold genus-g meshes. A planar parameterization is constructed by exploiting the topological structure of the mesh. This planar parameterization can be represented by a surface which is defined over parallel g-planes that represents g-holes. The proposed parameterization method satisfies the nonoverlapping requirement for any type of positive barycentric weights, including asymmetric weights. Moreover, convergence is guaranteed according to the Gauss-Seidel method.