bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluoxetine alters mu opiod receptor expression in obese Zucker rat hypothalamus
Authors: Churruca I. , Casis L. , Portillo M.P. , Macarulla M.T. , Záate J. , Pascual J. , Echevarría E. 
Published: August 2004

AbstractThe aim of the present work was to study the potential involvement of hypothalamic opiod system in the anorectic machanism of fluoxetine in obese Zucker rats, assessing the effects of chronic fluoxetine treatment on mu opiod receptor immunostaining in several hypothalamic regions. Male obese Zucker (fa/fa) rats were administered with fluoxetine (10 mg/kg; i.p.) daily for two weeks. The control group was given 0.9% NaCl solution. Regional hypothalamic immunostaining for mu opiod receptor was carried out. Fluoxetine administration increased the numbers of neural cells positively immunostained for mu opiod receptor in the hypothalamic, paraventricular, arcuate, ventromedial and suprachiasmatic nuclei, as well as the medial preoptic and lateral hypothalamic areas, without changed in dorsomedial, supraoptic and periventricular nuclei, and the lateral preoptic area. These results suggest the involvement of hypothalamic opiod system in fluoxetine‐induced anorexia in obese Zucker rats. Increased regional hypothalamic density of neural cells expressing mu opiod receptors after fluoxetine treatment could be a compensatory mechanism against a possible reduction in opiodergic tone.
Initiation of functional synapses is associated with AMPA receptor expression
Authors: Chono Koji , Shiga Hatsuki , Tojima Takuro , Ito Etsuro 
Published: August 2004

AbstractIn the present study, we identified the key protein that modulates the initiation of functional glutamatergic synapses in developing cortical neurons. First, we found a day in vitro that marked a critical increase in the number of functional synapses by the application of cyclic AMP, as demonstrated with Ca2+ imaging. We then examined the changes in the expression levels of proteins, which were expected to play a role in glutamatergic synapses, by the application of cyclic AMP. Our findings suggest that the expression of the α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole proprionic acid (AMPA) receptors modulates the initiation of functional synapses in developing neurons, and that immature neurons already contain N‐methyl d‐aspartate (NMDA) receptors and presynaptic proteins such as synaptophysin.
The influence of age on the treadmill exercise‐induced c‐Fos expression in the hippocampus of rats
Authors: Kim Sang‐Ho , Kim Hong , Kim Sung‐Soo , Shin Mal‐Soon , Chang Hyun‐Kyung , Lee Taeck‐Hyun , Jang Mi‐Hyeon , Shin Min‐Chul , Lee Hee‐Hyuk , Kim Young‐Pyo , Kim Chang‐Ju 
Published: August 2004

Abstractc‐Fos has been used as a neuronal activity marker. Here, we examined the influence of age on the treadmill running‐induced c‐Fos expression in rat hippocampus. Rats of exercise groups were forces to run on treadmill for 30 min. once a day for 5 consecutive days. Without exercise, c‐Fos expression was highest in 8‐week old rats. Treadmill exercise significantly enhanced the c‐Fos expression in the hippocampus of rats in all ages. In the CA region, the increase of the c‐Fos expression by treadmill exercise was highest in 4‐week old rats. In the dentate gyrus, the increase of the c‐Fos expression by treadmill exercise was highest in 62‐week old rats. The data show that age is an important factor for the regulation of the c‐Fos expression in the hippocampus and that the ability of the treadmill exercise enhancing the c‐Fos expression is dependent on age status.
Long‐term angiotensin converting enzyme inhibition dose‐dependently improves nerve conduction velocity and evoked potential latencies in streptozotocin‐diabetic rats
Authors: Manschot Sanne M. , Kappelle L.J. , Gispen W.H. , Biessels G.J. 
Published: August 2004

AbstractVascular disease probably plays an important role in the pathogenesis of cerebral complications that are associated with diabetes mellitus. Previous studies showed that treatment with the angiotensin converting enzyme‐inhibitor enalapril (24 mg/kg) prevented neurophysiological and cognitive deficits in streptozotocin diabetic rats, and improved cerebral blood flow, despite a reduction in systemic mean arterial blood pressure. The present study examined if these effects could be sustained with long‐term treatment, and if treatment with a lower dose (12 mg/kg) could prevent peripheral and central neurophysiological deficits without causing hypotension. Sciatic nerve conduction velocities were measured every three weeks after diabetes induction, until 24 weeks. Brain stem auditory (BAEP) and visual evoked potentials (VEP) were measured every three weeks from 10 weeks after diabetes induction, until 25 weeks. Nerve conduction velocity was decreased, and BAEP and VEP latencies increased in untreated diabetic rats. At the end of follow‐up 12 mg/kg enalapril partially prevented evoked potential abnormalities, but not nerve conduction deficits, whereas 24 mg/kg enalapril largely prevented deficits in nerve conduction velocity (p<0.001), as well as BAEP (p<01) and VEP latencies (p<0.05). Mean arterial blood pressure was 122 mmHg in the untreated diabetic group, 75 mmHg in the 24 mg/kg group and 112 mmHg in the 12 mg/kg group. Sustained treatment with enalapril at 24 mg/kg was associated with increased mortality, which may be related to the marked hypotension at this dosage. We conclude that long‐term treatment with enalapril at a dose of 24 mg/kg can prevent peripheral and central neurophysiological deficits in streptozotocin diabetic rats, but that adverse effects preclude sustained treatment.
Eigenvalue approximation of the biharmonic eigenvalue problem by Ciarlet‐Raviart scheme
Authors: Chen Wei 
Published: August 2004

AbstractUsing the technique of eigenvalue error expansion and the technique of integral identities, we derive higher order convergence rate of the eigenvalue approximation for the biharmonic eigenvalue problem based on the Ciarlet‐Raviart discretization. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2005
A posteriori error estimates with the finite element method of lines for a Sobolev equation
Authors: Tran Thanh , Duong Thanh‐Binh 
Published: August 2004

AbstractA posteriori error estimates for semidiscrete finite element methods for a nonlinear Sobolev equation are considered. The error estimates are obtained by solving local nonlinear or linear pseudo‐parabolic equations for corrections to the solution on each element. The ratios of these estimates and the true errors are proved to converge to 1, implying that the estimates can be used as indicators in adaptive schemes for the problem. Numerical results underline our theoretical results. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2005
Reliable, goal‐oriented postprocessing for FE‐discretizations
Authors: Suttmeier F. T. 
Published: August 2004

AbstractIn this article we present strategies to improve the quality of adaptive FE‐approximations measured in terms of linear functionals. The ideas are based on the so called dual‐weighted‐residual (DWR) approach to a posteriori error control for FE‐schemes. In more details, we exploit those parts of an underlying error representation, which are completely computable, to improve the FE‐solution. Furthermore, the remaining parts of the error identity can be estimated by well‐established a posteriori energy estimates yielding reliable error bounds for the postprocessed values. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2005
Late relapse of osteosarcoma: Implications for follow‐up and screening
Authors: Strauss Sandra J. , McTiernan Anne , Whelan Jeremy S. 
Published: August 2004

AbstractLong‐term disease‐free survival in patients with localised osteosarcoma treated in large multicentre randomised trials is over 50%. Most relapses occur early, usually within 2–3 years. Relapse after 5 years is uncommon and has been infrequently described. Eight patients with osteosarcoma treated at The London Bone and Soft Tissue Tumour Service since 1986 developed recurrence of disease after 5 years, the latest 14 years after the initial diagnosis. Five patients developed pulmonary metastases, two patients isolated bone metastases and one patient intra‐abdominal metastases. Although a second complete remission was achieved in six patients, four patients relapsed again, all with pulmonary metastases. Two patients had co‐existent brain metastases. One of those with a second recurrence has achieved a further complete remission and remains well 50 months after the most recent treatment. A second patient is disease‐free 24 months after complete excision of an isolated pulmonary metastasis and one further patient is disease‐free 6 months after chemotherapy and pneumonectomy for pleural and pulmonary metastases. Five patients have died of disease with a median survival from the date of relapse of 17 months (2–68 months). Current data looking at long‐term outcome of patients with osteosarcoma is limited. Reports of late relapse are rare as numbers are small, thus long‐term surveillance of patients is essential. It is possible that sites of relapse are more unusual, and more extensive staging may be necessary when late relapse occurs. © 2004 Wiley‐Liss, Inc.
Effectiveness of fixed 50% nitrous oxide oxygen mixture and EMLA cream for insertion of central venous catheters in children
Authors: Abdelkefi Abderrahman , Abdennebi Yosr Ben , Mellouli Fethi , Othman Tarek Ben , Torjman Lamia , Ladeb Saloua , Aouf Sami , Béjaoui Mohamed , Abdeladhim Abdeladhim Ben 
Published: August 2004

AbstractBackgroundAlthough the equimolecular mixture of oxygen and nitrous oxide (EMONO) seems a good choice to relieve procedure‐related pain in children, it has not been evaluated for insertion of central venous catheters in children. To assess the safety and the effectiveness of this gas mixture for insertion of central venous catheters, we conducted a prospective observational study.ProcedureThis study was performed by the “Centre National de Greffe de Moelle Osseuse.” Procedure and inhalation characteristics, as well as pain evaluations and side effects, were reported.ResultsFifty central venous catheters were inserted in 50 consecutive children. Median age was 7 (range, 4–13) years. An anesthesiologist was responsible for delivering EMONO, and provided constant surveillance throughout the procedure. EMLA cream was applied 2 hr before EMONO inhalation. No associated drugs were used. All catheters were inserted by the same experienced physician in the operating theater. Median inhalation length was 5 min (range, 3–6) before starting catheter's insertion and 12 min (range, 9–25) for the total inhalation. Median procedural pain evaluations were 10 (range, 0–30) for children on a 0–100 visual analog scale (VAS). Minor side effects were observed during eight (16%) inhalations. These side effects were euphoria (14%), deep sedation (4%), nausea and vomiting (2%), hallucinations (2%). All side effects were transient and resolved within 5 min after removing the inhalation device.ConclusionsThis study which shows that EMONO is effective for insertion of central venous catheters in children and represents a simple and safe alternative to general anesthesia. Pediatr Blood Cancer 2004;43:777–779. © 2004 Wiley‐Liss, Inc.
Drug‐induced upper gastrointestinal disorders requiring hospitalization: a five‐year study in a South Indian hospital
Authors: Devi D. Padmini , Sushma M. , Guido S. 
Published: August 2004

AbstractPurposeTo study the clinical spectrum of drug induced upper gastrointestinal tract (GIT) disorders requiring hospitalization and establish the causal relation between drug and disorder using WHO causality definitions.MethodsCase‐records of patients in the Department of Gastroenterology (from January 1998 to December 2002) hospitalized with diagnoses of drug induced upper GIT disorders were analyzed retrospectively. The causality assessment of each disorder was done based on WHO causality definitions.ResultsOut of 101 cases identified over the study period, 8 were categorized as certain, 87 as probable and 6 cases as possible. The certain and probable cases (95) were analyzed. Of these, 13 were in 1998, 14 in 1999, 18 in 2000, 20 in 2001 and 30 in 2002. The drug class most commonly implicated with adverse drug reactions was non‐steroidal anti‐inflammatory drugs (NSAIDs) (76.8%). Among individual drugs, aspirin was most commonly involved (32.6%). Results of endoscopy revealed gastric erosions (40.2%), combination of gastric ulcer and gastric erosions (16.1%), gastric ulcer (15.0%), duodenal ulcer (13.8%), normal (13.8%) and duodenal erosions (1.1%). Risk factors noticed were chronic smoking (16.8%), alcohol consumption (13.7%), smoking and alcohol use (21.1%), history of peptic ulcer (10.5%) and chronic steroid use (1.1%).ConclusionNSAIDs especially aspirin were implicated in maximum number of patients. An increase in occurrence over 5 years, a wide spectrum of disorders and various risk factors were noticed. Copyright © 2004 John Wiley & Sons, Ltd.
Structure and mechanical properties of polyamide‐6,6/poly(ethylene terephthalate) blends
Authors: Retolaza A. , Eguiazábal J. I. , Nazábal J. 
Published: August 2004

AbstractPolyamide‐6,6 (PA)/poly(ethylene terephthalate) (PET) blends were obtained by direct injection molding over the whole composition range. Besides the two crystalline phases, the blends were composed of a pure amorphous PET phase, and a probably pure PA amorphous phase. The crystallinity of PA and PET did not change in the blends, although PA nucleated the crystallization of PET. The morphological heterogeneity was low because, although large particles were seen, they mostly contained many small (typically 0.3 μm) occlusions. This fairly homogeneous structure is attributed to the reactions observed during melt blending. The Young's modulus and yield stress of the blends followed the rule of mixtures, in good agreement with the lack of change of the crystallinity content, specific volume and orientation of the two components of the blends when they are mixed. The ductility values were also very close to those predicted by the rule of mixtures, with an absolute synergism in the 10/90 blend indicating compatibility. This positive mechanical behavior contrasts with that observed in previous works, and is attributed to the way PET crystallizes, to the highly dispersed morphology, and to the highly amorphous character of the blends obtained in this study. The ductile nature of the blends after annealing at either 80°C for one day or 100°C for 30 min indicated the considerable temperature resistance of these highly dispersed and partially reacted blends. Polym. Eng. Sci. 44:1405–1413, 2004. © 2004 Society of Plastics Engineers.
Numerical investigation of the influence of material properties and adhesive layer thickness on the heating efficiency of microwave curing of an adhesive‐bonded joint
Authors: So H. W. , Taube A. 
Published: August 2004

AbstractIn the process of microwave curing of an adhesive‐bonded joint, both the adhesive layer and the adherends affected the heating efficiency of the joint. As an extension of previous studies, the influences of changing the properties of the components of the joint on the heating efficiency were predicted by simulations that were based on the numerical model developed previously. The influence of adhesive thickness was also studied. The properties that directly affected power dissipation and heat loss of the adhesive layer were found to be important to the heating efficiency of the process. The heating rate was also sensitive to the thickness of the adhesive layer. Polym. Eng. Sci. 44:1414–1418, 2004. © 2004 Society of Plastics Engineers.
Thermal properties of biaxially deformed in situ composites
Authors: Seo Youngwook P. , Seo Yongsok 
Published: August 2004

AbstractThe thermal properties of biaxially blown poly(etherimide) (PEI) films containing a thermotropic liquid crystalline polymer (TLCP) were studied using differential scanning calorimetry, thermogravimetric analysis, wide‐angle X‐ray diffraction and dynamic mechanical thermal analysis. The effects of the compatibilizer and thermal annealing on the thermal properties of biaxially oriented TLCP films were investigated. Though the compatibilizer (poly(ester imide)) improved deformation of the TLCP phase (poly ester amide) and adhesion between the matrix and the TLCP phase, which improved mechanical properties, it did not significantly affect the thermal properties of the in situ composite films. The film degradation behavior corroborated the role of the compatibilizer. Since a relatively small amount of TLCP (10 wt%) was added to the matrix and the matrix PEI was amorphous, the effect of annealing on the TLCP structure was not obvious. By the same token, while the effect of the deformation in the circumferential direction (a change in the blow‐up ratio) was manifest in mechanical property improvements, its effect on the thermal properties was not obvious. All films showed similar thermal expansion behaviors, regardless of the thermal history and of the compatibilizer addition. Thus, there is an optimum amount of the compatibilizer required to obtain optimal mechanical properties for in situ composite films without causing a deterioration of their thermal properties. Polym. Eng. Sci. 44:1419–1428, 2004. © 2004 Society of Plastics Engineers.
Rheological, mechanical and biodegradation studies on blends of thermoplastic starch and polycaprolactone
Authors: Shin Boo‐Young , Lee Sang‐II , Shin Young‐Sub , Balakrishnan Sunder , Narayan Ramani 
Published: August 2004

AbstractPolycaprolactone (PCL) has been blended with thermoplastic starch (TPS), prepared from regular corn starch and glycerol, in a twin‐screw extruder. The rheological, mechanical, thermal and morphological properties of the blends were examined. Differential Scanning Calorimetry (DSC) and Scanning Electron Microscopy (SEM) studies revealed that PCL/TPS blends are thermodynamically immiscible. However, they form compatible blends as a result of the hydrogen bonding interaction between the ester carbonyl of PCL and the OH groups on starch. Biodegradability of the blends increased with increasing TPS content. Dynamic viscoelastic measurements concluded that blends containing above 60‐wt% TPS had higher storage and loss moduli than those of pure TPS and PCL. In addition, these blends had higher complex viscosities. Polym. Eng. Sci. 44:1429–1438, 2004. © 2004 Society of Plastics Engineers.
Modeling and simulation of stretch blow molding of polyethylene terephthalate
Authors: Pham X.‐T. , Thibault F. , Lim L‐T. 
Published: August 2004

AbstractWhen polyethylene terephthalate (PET) is stretched, it exhibits strain‐hardening properties, which are temperature and strain‐rate dependent. In this paper, two grades of PET are experimentally characterized using biaxial tests. A visco‐hyperelastic model is used to describe the stretching behavior for the polymer. A biaxial characterization method is employed to determine the model parameters using a robust nonlinear curve‐fitting program. This model can represent adequately well the stretching behavior of PET. Based on this model, the membrane finite element formulation is developed to simulate the stretch blow molding process. Two bottles of different designs, produced based on the single‐stage injection blow molding process, are used to validate the model. Good agreement with the bottle thickness profile is observed. Polym. Eng. Sci. 44:1460–1472, 2004. © 2004 Society of Plastics Engineers.
Development and characterization of reactively extruded PVC/polystyrene blends
Authors: Haba Y. , Narkis M. 
Published: August 2004

AbstractPVC/PS blends are obtained through a reactive extrusion–polymerization method by the absorption of a solution of styrene monomer, initiator, and a crosslinking agent in commercial suspension‐type porous polyvinyl chloride (PVC) particles, forming a dry‐blend with a relatively high monomer content. These PVC/styrene dry‐blends are reactively polymerized in a twin‐screw extruder in the melt state. They do not contain monomer residues as detected by GC. The transparency, fracture surface morphology, thermal stability, rheology and static and dynamic mechanical properties of these blends are compared to physical PVC/PS blends at similar compositions. Owing to the high polymerization temperature (180°C), short PS chains are formed in the reactive extrusion process. These short chains are dispersed both as a separate phase of ∼2 μm particles (recognized by SEM) and also as molecularly dispersed chains enhancing plasticization and compatibilization. The molecularly dispersed short PS chains tend to plasticize the PVC phase, reducing its melt viscosity and glass transition temperature. The content of the short PS chains forming the dispersed separate PS particles is too low for DMTA to detect a separate Tg. Thus, reactively extruded PVC/PS blends exhibit single Tg transitions at lower temperatures compared with the neat PVC. Migration of the PVC's low‐molecular‐weight additives (lubricants and thermal stabilizer) to the PS phase is observed in the physical PVC/PS blends, causing antiplasticization of the PS phase. This results in both reduction of the Tg and an increase in the thermal stability of the PS phase in the physical PVC/PS blends. Comparing TGA thermograms of reactively extruded and physical PVC/PS indicates that the PS formed in the extruder is different from the commercial PS. This can stem from various chemical reactions that can take place in the studied reactive polymerization process. Polym. Eng. Sci. 44:1473–1483, 2004. © 2004 Society of Plastics Engineers.
Online measurements of crystallinity using Raman spectroscopy during blown film extrusion of a linear low‐density polyethylene
Authors: Cherukupalli Srinivas S. , Ogale Amod A. 
Published: August 2004

AbstractReal‐time, Raman spectroscopic measurements of crystallinity during the blown film extrusion of a linear low‐density polyethylene (LLDPE) are reported. The take‐up ratio (TUR), inflation air pressure, and cooling conditions were varied, and their effect on the development of crystallinity was studied. The results indicate that the crystallization process starts at the freeze line, increases along the film line, and finally plateaus. It was observed that with changing processing conditions, the differences in the profiles for crystallinity were evident when plotted as a function of time rather than distance along the machine direction. The influence of take‐up ratio and bubble inflation air pressure on the development of crystallinity clearly established the role of flow‐induced crystallization during film extrusion. Polym. Eng. Sci. 44:1484–1490, 2004. © 2004 Society of Plastics Engineers.
Kinetic and thermodynamic considerations in the synthesis of a new three‐arm poly(ε‐caprolactone)
Authors: Balakrishnan Sunder , Krishnan Mohan , Dubois Philippe , Narayan Ramani 
Published: August 2004

AbstractA new high‐molecular‐weight three‐arm poly(ε‐caprolactone) (PCL) polymer was synthesized in bulk (in the absence of any solvent) by using aluminum tri‐sec butoxide as a tri‐functional initiator. The ring‐opening polymerization of ε‐caprolactone occurs via a coordination‐insertion mechanism that links three growing polyester chains to the Al central atom via metal alkoxide bonds. The global kinetics of the bulk polymerization was determined, and a kinetic model based on monomer‐polymer equilibrium was developed to predict the fractional extent of monomer conversion. Monomer conversions in excess of 95% to form high‐molecular‐weight PCL were achieved. Polym. Eng. Sci. 44:1491–1497, 2004. © 2004 Society of Plastics Engineers.