bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of cigarette smoke on lipid peroxidation, antioxidant enzymes and NMDA receptor subunits 2A and 2B concentration in rat hippocampus
Authors: Delibas Namik , Ozcankaya Ramazan , Altuntas Irfan , Sutcu Recep 
Published: February 2003

AbstractThe effect of cigarette smoke on lipid peroxidation and antioxidant enzymes such as catalase, superoxide dismutase, glutathione peroxidase and on the concentration of N‐methyl‐d‐aspartate receptor (NMDAR) subunits 2A and 2B in the hippocampus of Sprague‐Dawley rats exposed to cigarette smoke for 2h/day for a period of 4 weeks was determined. It was observed that NMDAR 2A and 2B concentrations in the hippocampus were enhanced in the case of animals exposed to cigarette smoke, whereas lipid peroxidation and antioxidant enzyme activities did not show any change as compared to control animals. The results of our study suggest that cigarette smoke induces NMDAR 2A and 2B expression in the hippocampus, and that this is not due to an increased lipid peroxidation, because cigarette smoke has no effect on lipid peroxidation and antioxidant enzyme activities in the hippocampus. Copyright © 2002 John Wiley & Sons, Ltd.
Enantiomeric discrimination of pyrethroic acid esters on polysaccharide derived chiral stationary phases
Authors: Kim Byoung‐Hyoun , Lee Sang Uck , Kim Kun Tai , Lee Joo‐Young , Choi Nak Hee , Han Young‐Kyu , Ok Jong Hoa 
Published: February 2003

AbstractEnantiomeric separation of pyrethroic acid methyl and ethyl esters was examined on cellulose‐based chiral stationary phases (CSPs): chiralcel OD (cellulose tris(3,5‐dimethylphenyl carbamate)) and chiralcel OF (cellulose tris(4‐chlorophenyl carbamate)). The good resolution of pyrethroic acid esters was achieved on chiralcel OD and OF. Separation factors ranged from 1.19–5.12 for Chiralcel OD and 1.00–1.59 for chiralcel OF. Hexane/2‐propanol (100:0.15, v/v %) was used as the eluent. The resolution capability of CSPs was greater chiralcel OD than chiralcel OF in the case of the pyrethroic acid esters. The flow rate was 0.8 ml/min and detection was set at 230 nm. The results of the chromatographic data and molecular mechanics suggest that steric effect was a major factor in the enantioseparation. Furthermore, the hydrogen bond between analytes and CSP played an important role in the chiral recognition. Chirality 15:276–283, 2003. © 2003 Wiley‐Liss, Inc.
Numerical simulations on fatigue destruction of ultra‐high molecular weight polyethylene using discrete element analyses
Authors: Shibata Nobuyuki , Tomita Naohide , Ikeuchi Ken 
Published: February 2003

AbstractUltra‐high molecular weight polyethylene (UHMWPE) is a heterogeneous material composed of a networked substructure of grain boundary and grain aggregation. A new numerical model based on the discrete element method (DEM) was proposed to examine microscopic defect formation and propagation in UHMWPE. Numerical simulations were carried out using this model under two types of loading condition: unidirectional repetitive compression (simple loading) and bidirectional repetitive compression (switched loading). Subsurface defects were initiated and propagated in the vicinity of grain boundaries under both loading conditions. The defect propagation behavior was especially sensitive to grain boundary allocation under switched loading. An increase in defects was more rapid under switched loading than under simple loading. These numerical results showed qualitatively good agreement with experimental ones. It is suggested that the newly developed numerical method based on the DEM is a promising method to investigate fatigue behavior of a heterogeneous material such as UHMWPE under complicated loading conditions. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 64A: 570–582, 2003
Distribution patterns of the membrane glycoprotein CD44 during the foreign‐body reaction to a degradable biomaterial in rats and mice
Authors: Bonnema Harmke , Popa Eliane R , van Timmeren Mirjan M. , van Wachem Pauline B. , de Leij Lou F. M. H. , van Luyn Marja J. A. 
Published: February 2003

AbstractAlthough biomaterials have been used in the clinical setting for a long time, little is known of the molecular mechanisms underlying the foreign‐body reaction (FBR). A good understanding of these mechanisms is requisite for the controlled regulation of the FBR needed to prevent adverse tissue reactions and thus to improve the function of the biomaterial. Macrophages are essential in the inflammatory reaction in, as well as around, the implants, and they also are believed to initiate most of the adverse responses. Typically, during the FBR macrophages become activated and fuse into multinucleated giant cells (MnGCs). CD44, an integral membrane glycoprotein expressed on a broad spectrum of cell types, is involved in MnGC formation in vitro and in inflammation processes in general. In vivo it is not known whether CD44 is part of a specific protein machinery that enables macrophage fusion or whether it has additional functions in the FBR. In the present in vivo study, CD44 expression patterns were followed in rats and mice during the FBR to a degradable collagen type I biomaterial. We found that CD44 is upregulated on all migrating cells and on newly formed blood vessels at the onset of the FBR and that MnGCs, up to week 15 postimplantation, expressed CD44. Although no evidence was found that CD44 participates in macrophage fusion leading to multinucleation, it nevertheless may be an interesting target molecule for modulating the FBR in vivo, possibly by affecting cell activation, cell migration towards the biomaterial, vascularization, and MnGC formation. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 64A: 502–508, 2003
Does digital rectal examination affect uroflowmetry measurements?
Authors: Aybek Zafer , Sinik Zafer , Oguzulgen İbrahim , Turan Tahir , Güler Gökhan , Tuncay Levent 
Published: February 2003

AbstractAimsTo determine whether digital rectal examination (DRE) would affect uroflowmetry parameters and whether these findings were not due to the circaidan changes.MethodsA total of 79 male patients (59 in study and 20 in control group) were included in this study. First uroflowmetry was done at 10:00 am just before the genitourinary physical examination in the study group. Second and third uroflowmetry was performed at the 6th and 24th hour after the first uroflowmetry. The same uroflowmetry tests were done in a control group without DRE. Voided volume and maximum and average flow rate parameters of uroflowmetry were interpreted in our study. The relationship among first, second, and third uroflowmetry parameters were determined in the study and control groups.ResultsThere were statistically no difference between the mean first, or 6th‐ or 24th‐hour uroflowmetry parameters of the study and control groups (P > 0.05).ConclusionsWe could not find any effect of DRE on uroflowmetry parameters. Studies in a larger patient series would be appropriate for recommending DRE before or after uroflowmetry test. Neurourol. Urodynam. 22:138–141, 2003. © 2003 Wiley‐Liss, Inc.
Population analyses of sustained‐release verapamil in patients: Effects of sex, race, and smoking
Authors: Kang Dongwoo , Verotta Davide , Krecic‐Shepard Mary Ellen , Modi Nishit B. , Gupta Suneel K. , Schwartz Janice B. 
Published: February 2003

ObjectiveOur objective was to determine the effects of age, sex, and sustained‐release formulation on apparent oral clearance of sustained‐release racemic verapamil in patient populations.MethodsPopulation pharmacokinetic analyses were performed on data from 186 patients with hypertension, coronary artery disease, or supraventricular arrhythmias who were receiving long‐term sustained‐release oral racemic verapamil (Covera SR in 105 patients, Calan SR in 67 patients, and other formulations in 14 patients; mean ± SD dose, 280 ± 139 mg) for clinical care or as a part of phase III efficacy studies. Of those 186 patients, 135 were men (age, 63 ± 12 years; ideal body weight, 70.7 ± 6.6 kg) and 51 were women (age, 60 ± 17 years; ideal body weight, 53.7 ± 7.2 kg) . Verapamil was measured by HPLC, and population analyses were performed by use of NONMEM software. Sex, age, and formulation were the covariates considered in the population model building. Subgroup analyses of race, smoking, and alcohol consumption were also performed. Significance of covariates was determined by likelihood ratio tests.ResultsSex significantly affected steady‐state clearance of oral sustained‐release racemic verapamil. Apparent oral clearance of sustained‐release verapamil was 23.8 ± 2.3 mL/min per kilogram in women compared with 18.6 ± 3.4 mL/min per kilogram in men. Clearance estimates were faster in black subjects compared with white subjects, as well as in smokers compared with nonsmokers. Effects of age, formulation, and alcohol consumption were not detected.ConclusionsIn middle‐aged and older patients, apparent oral clearance of sustained‐release racemic verapamil was affected by sex (faster in women compared with men), race (faster in black subjects compared with white subjects), and smoking (faster in smokers compared with nonsmokers) but not by age, alcohol, or formulation.Clinical Pharmacology & Therapeutics (2003) 73, 31–40; doi: 10.1067/mcp.2003.21
Electroreception inG. carapo: detection of changes in waveform of the electrosensory signals
Authors: Aguilera Pedro A. , Caputi Angel A. 
Published: February 2003

SUMMARYElectric fish evaluate the near environment by detecting changes in their self-generated electric organ discharge. To investigate impedance modulation of the self-generated electric field, this field was measured at the electrosensory fovea of Gymnotus carapo in the presence and absence of objects. Changes in local fields provoked by resistive objects were predicted by the change in total energy. Objects with capacitive impedance generated large variations in the relative importance of the different waveform components of the electric organ discharge. We tested the hypothesis that fish discriminate changes in waveform as well as increases in total energy using the novelty response, which is a behavioural response consisting of a transient acceleration of EOD frequency that can follow a change in object impedance. For resistive loads, the amplitude of novelty responses was well predicted by the increase in total energy. For complex loads, the amplitude of novelty responses was correlated not only with increases in total energy but also with waveform changes, consisting of reductions in the early slow negative wave and increases in the late sharp negative wave. The total energy and waveform effects appeared to be additive. These results indicate that G. carapo discriminates complex impedance based on an evaluation of different waveform parameters.
Melatonin effect on renal oxidative stress under constant light exposure
Authors: Túnez Isaac , del Carmen Muñoz María , Feijoo Montserrat , Valdelvira Manuel E. , Rafael Muñoz‐Castañeda Juan , Montilla Pedro 
Published: February 2003

AbstractRecently, numerous studies have shown antioxidant actions of melatonin. Melatonin at both physiological and pharmacological levels stimulates glutathione peroxidase, glutathione reductase and superoxide dismutase activities in the brains of rats and chickens. This study was designed to evaluate the effect of melatonin on nephropathy and oxidative stress under constant light exposure. Nephropathy was induced by adriamycin administered in a single dose (25 mg kg−1 b.w., i.p.). Melatonin was injected i.p. (1000 μg kg−1 b.w./day). Malondialdehyde, reduced glutathione, glutathione peroxidase, glutathione reductase, glutathione transferase, catalase and superoxide dismutase were determined in kidney. Urea, creatinine and total proteins in plasma and proteinuria were evaluated and melatonin was determined. Results show a decrease in melatonin levels. Similar effects occurred with the antioxidant enzyme activities and reduced glutathione. Likewise, adriamycin and constant light induced significant enhancement of malondialdehyde. All changes induced both by adriamycin and constant light were reverted to normal by melatonin administration. Constant light exposure was associated with an increase in oxidative stress and nephropathy induced by adriamycin. Treatment with melatonin decreased lipid peroxides, and permitted a recovery of reduced glutathione, scavenger enzyme activity and parameters of renal function. Copyright © 2002 John Wiley & Sons, Ltd.
Bone formation in CaP‐coated and noncoated titanium fiber mesh
Authors: Vehof J. W. M. , van den Dolder J. , de Ruijter J. E. , Spauwen P. H. M. , Jansen J. A. 
Published: February 2003

AbstractThe osteogenic activity of calcium phosphate (CaP)‐coated and noncoated porous titanium (Ti) fiber mesh loaded with cultured syngeneic osteogenic cells after prolonged in situ culturing was compared in a syngeneic rat ectopic assay model. Rat bone marrow (RBM) cells were loaded onto the CaP‐coated and noncoated Ti scaffolds using either a droplet or a suspension loading method. After loading, the RBM cells were cultured for 8 days in vitro. Thereafter, implants were subcutaneously placed in 39 syngeneic rats. The rats were euthanized and the implants retrieved at 2, 4, and 8 weeks postoperatively. Further, in the 8 week group fluorochrome bone markers were injected at 2, 4, and 6 weeks. Histological analysis demonstrated that only the CaP‐coated meshes supported bone formation. The amount of newly formed bone varied between single and multiple spheres to filling a significant part of the mesh porosity. In the newly formed bone, osteocytes embedded in a mineralized matrix could be observed clearly. On the other hand, in the noncoated titanium implants, abundant deposition of calcium‐containing material was seen. This deposit lacked a bonelike tissue organization. Further analysis revealed that the cell‐loading method did not influence the final amount of bone formation. In CaP‐coated implants the accumulation sequence of the fluorochrome markers showed that bone formation started on the mesh fibers. In conclusion, our results prove that the combination of a thin CaP coating, Ti‐mesh, and RBM cells can indeed generate ectopic bone formation after prolonged in vitro culturing. No effect of the loading method was observed on the final amount of bone. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 64A: 417–426, 2003
Proinflammatory phenotype of endothelial cells after coculture with biomaterial‐treated blood cells
Authors: Lester Elizabeth A. , Babensee Julia E. 
Published: February 2003

AbstractAn understanding of the endothelial cell/blood/biomaterial interactions is central to advancing the success of cardiovascular devices that continue to fail because of the lack of nonthrombogenic biomaterials. A simplified endothelial cell/blood cell/biomaterial static model was used to assess these interactions. Human whole blood or isolated blood cells (mononuclear cells, neutrophils, platelets) were pretreated with biomaterial beads with different surface chemistries: polystyrene (PS), PS beads grafted with 3‐kDa polyethylene glycol (PEG) with either hydroxyl (PS‐PEG‐OH) or amine (PS‐PEG‐NH2) terminal groups at bead concentrations of 5.4 or 54 × 104 beads/mL. Leukocyte and platelet activation and microparticle formation was assessed using flow cytometry. Biomaterial‐activated whole blood or isolated cells or mononuclear cell fractions were applied to human umbilical cord endothelial cells (HUVEC) for static coculture, and the resultant proinflammatory HUVEC phenotype was characterized. ICAM‐1 and E‐selectin expression on HUVEC was increased after 4‐h static coculture with biomaterial‐treated human whole blood or mononuclear cells but not neutrophils or platelets. VCAM‐1 expression on HUVEC was similarly increased after 24‐h static coculture but not after 4 h of coculture. Increased concentrations of cytokines, IL‐6, IL‐8, and MCP‐1, were detected in the supernatant of cocultures of HUVEC with biomaterial‐treated whole blood or mononuclear cells but not neutrophils or platelets, compared with the media control. After 24 h, cytokine release was significantly increased for both IL‐8 and MCP‐1 but not IL‐6 above concentrations after 4 h of coculture. Neither the cell adhesion molecule (CAM) expression nor cytokine release induced by coculture with biomaterial‐treated whole blood or isolated cells was dependent on either material surface chemistry or material surface area. The changes in HUVEC CAM expression and cytokine release induced by biomaterial‐treated mononuclear cells can be attributed predominantly to adherent cells on beads and nonadherent bulk cells with moderate regulation by the soluble supernatant; however, mononuclear cell‐derived microparticles induced no significant changes in CAM expression or cytokine release after static coculture with HUVEC. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 64A: 397–410, 2003
RGTA modulates the healing pattern of a defect in a monolayer of osteoblastic cells by acting on both proliferation and migration
Authors: Blanquaert Frédéric , Carpentier Gilles , Morvan Frédéric , Caruelle Jean‐Pierre , Barritault Denis , Tardieu Michèle 
Published: February 2003

AbstractA family of heparan‐like polymers, RGTAs, was shown to promote repair of various tissues. Like heparin and heparan‐sulfates, RGTAs potentiate in vitro the biological activities of heparin‐binding growth factors (HBGFs) and protect them against proteolytic degradation. It was postulated that RGTAs stimulate bone healing by interacting with HBGFs released in the wound site and, subsequently, by promoting the proliferation of cells implicated in this process. In a previous report, we examined how RGTA can modulate the proliferation of MC3T3‐E1 osteoblastic cells. To further complete this study and to support this hypothesis, we developed an in vitro model of bone repair and examined the effects of RGTA alone or in association with FGF2, BMP‐2, and TGF‐β1 which are representative of HBGFs known to stimulate bone repair. The model consisted of a 6‐mm reproducible defect created on a MC3T3‐E1 cell monolayer. In the presence of the different products added to the medium, the process of wound repair was measured through the filling of the acellular defect. We show that in 8 days, RGTA slightly inhibits repair alone compared to the control (2% FBS), that it inhibits the mitogenic effect of FGF2, and that it amplifies the inhibitory effect of BMP‐2 and TGF‐β1. Repair was realized by an association of cell migration and cell proliferation mechanisms. To determine the part played by each process, DNA synthesis was evaluated for cell proliferation using an immunodetection technique [to measure incorporation of 5‐bromo‐2‐deoxyuridine (BrdU)], coupled with a computer‐assisted image analysis. The results show that the presence of RGTA (1) amplified the number of labeled nuclei compared to the control, (2) added to FGF2 or TGF‐β1, it reduced the number of labeled nuclei compared to FGF2 or TGF‐β1 alone, and (3) in the presence of BMP‐2, it amplified the number of labeled nuclei compared to BMP‐2 alone. Proper interpretation of these data requires a better understanding of the mechanism of action of RGTA on bone healing. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 64A: 525–532, 2003
Who plays the client? Collaborating with theater departments to enhance clinical psychology role‐play training exercises
Authors: Pomerantz Andrew M. 
Published: February 2003

AbstractThis article offers a description of a student‐active method of teaching clinical psychology applications, such as interviewing and psychotherapy, that involves collaboration between psychology and theater departments. Clinical psychology instructors recruit theater students to play the client roles in live dyads with the instructors or other students. These dyads may take place during or outside of class and may be videotaped for use in other educational settings. Practical and logistical issues are discussed, and empirical data are presented to demonstrate the effectiveness of this method. © 2003 Wiley Periodicals, Inc. J Clin Psychol 59: 363–368, 2003.
Motor evoked potentials from the striated urethral sphincter: A comparison of concentric needle and surface electrodes
Authors: Brostrom Soren , Jennum Poul , Lose Gunnar 
Published: February 2003

AbstractAimsThe aim of this study is to compare two different surface electrodes (intravaginal and intraurethral) with the concentric needle as a criterion standard and concomitant testing of the levator ani as a potential contaminator.MethodsThirty healthy women with a mean age of 52 years. Bland‐Altman plots were used to compare recorded latencies from the various electrodes and muscles.ResultsThere was no significant difference between the latencies recorded with the various electrodes from either muscle, but the limits of agreement were wide. However, the concentric needle electrodes proved more reliable with a higher rate of reproducible responses.ConclusionsWe did not encounter major difficulties in using the concentric needle electrode for recordings in the external urethral sphincter, and this electrode was also more reliable than either surface electrode. Therefore, we advocate the use of concentric needle electrodes in future studies. Neurourol. Urodynam. 22:123–129, 2003. © 2003 Wiley‐Liss, Inc.
Fluorescence lifetime imaging of unstained tissues: early results in human breast cancer
Authors: Tadrous Paul J , Siegel Jan , French Paul MW , Shousha Sami , Lalani El‐Nasir , Stamp Gordon WH 
Published: February 2003

AbstractFluorescence lifetime imaging (FLIM) depends on the fluorescence decay differences between tissues to generate image contrast. In the present study FLIM has been applied to fixed (but unstained) breast cancer tissues to demonstrate the feasibility of this approach for histopathological assessment. As the FLIM method relies on natural autofluorescence, it may be possible to circumvent tissue processing altogether and so FLIM has the potential to be a powerful new method of in vivo tissue imaging via an endoscopic or per‐operative approach in a variety of organs, as well as a research tool for in vivo animal models of disease. Unstained, alcohol‐fixed tissue samples from 13 patients were stimulated by laser pulses at 415 nm. The temporal decay of the autofluorescence was imaged over a period of 2 ns after cessation of the pulse. The decay rate at each image pixel was calculated as the ‘lifetime’ factor τ. A tissue classification scheme was used to define regions in each image. The average lifetimes of different tissue regions were compared. A total of 167 tissue regions were measured. Within individual fields, stroma had a larger τ (slower decay) than epithelium (p < 0.001). Within individual patients (taking the mean τ of a given tissue type across all fields from each patient), there was a statistically significant difference between benign and malignancy‐associated stroma (p < 0.05). Also, benign collagen had a longer τ than benign epithelium (p < 0.05). Multivariate analysis showed a significant difference between benign stroma, malignancy‐associated stroma, blood vessels, and malignant epithelium (p < 0.05). Statistically significant differences between benign and malignancy‐associated stroma were obtained even with small patient numbers, indicating that lifetime‐based instruments can be developed for real‐time diagnostic imaging with microscopic resolution. Copyright © 2003 John Wiley & Sons, Ltd.