bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and properties of PVA/PVP hydrogels containing chitosan by radiation
Authors: Nho Y. C. , Park K. R. 
Published: October 2002

AbstractRadiation can induce chemical reactions to modify polymers even when they are in the solid state or at a low temperature. Radiation crosslinking can be easily adjusted by controlling the radiation dose and is reproducible. The finished product contains no residuals of substances required to initiate the chemical crosslinking, which can restrict its application possibilities. In these studies, hydrogels for wound dressing were made from a mixture of chitosan and polyvinyl alcohol (PVA)/poly‐N‐vinylpyrrolidone (PVP) by freezing and thawing, gamma‐ray irradiation, or combined freezing and thawing and gamma‐ray irradiation. The physical properties of the hydrogel, such as gelation, water absorptivity, and gel strength, were examined to evaluate the usefulness of the hydrogels for wound dressing. The PVA/PVP composition was 60:40, PVA/PVP–chitosan ratio was in the range 9:1–7:3, and the concentration of, PVA/PVP–chitosan as a solid was 15 wt %. A mixture of PVA/PVP–chitosan was exposed to gamma irradiation doses of 25, 35, 50, 60 and 70 kGy to evaluate the effect of irradiation dose on the physical properties of hydrogels. Water‐soluble chitosan was used in these experiment. The physical properties of the hydrogels, such as gelation and gel strength, were higher when the combination of freezing and thawing and irradiation were used rather than just freezing and thawing. The PVA/PVP–chitosan composition and irradiation dose had a greater influence on swelling than gel content. Swelling percent increased as the composition of chitosan in PVA/PVP–chitosan increased. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1787–1794, 2002
Influence of water on the viscoelastic behavior of recycled nylon 6,6
Authors: Vallés‐Lluch A. , Camacho W. , Ribes‐Greus A. , Karlsson S. 
Published: October 2002

AbstractNylons are highly sensitive to moisture, as water molecules are able to form hydrogen‐bonded complexes with nitrogen and oxygen from the amide functional groups. In recycled nylon 6,6, a higher absorbed moisture content can be detected in comparison to virgin material. Moisture uptake is manifested in chemical and physical properties, and has important technological consequences, so the relationship between them must be assessed. Differential scanning calorimetry (DSC) has been used to measure the water content of different samples and physical changes have been analyzed by means of dynamic mechanical thermal analysis (DMTA). The relaxation zones of the dynamic‐mechanical relaxation spectra of the samples have been characterized according to the Fuoss‐Kirkwood equation and with help of the deconvolution method. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2211–2218, 2002
Effect of hydrothermal environment on moisture absorption and mechanical properties of wood flour–filled polypropylene composites
Authors: Lin Qunfang , Zhou Xiaodong , Dai Gance 
Published: October 2002

AbstractThe moisture absorption and mechanical properties of wood flour–filled polypropylene composites in a hydrothermal environment have been studied by immersing the composites in water at 23, 60, and 100°C. The degree of moisture absorption was found to be dependent on the modification of matrix, the weight percentage, mesh size, and surface treatment of wood flours. It increased with increasing the immersion temperature. The tensile strength of all composites with wood flours of different contents, mesh sizes, and surface treatments increased after immersion in water baths of various temperatures, to either greater or lesser extents. The flexural strength and modulus followed a similar trend when immersed in water at ambient temperature. However, the contrary was true for composites when immersed in 60 and 100°C water baths. The impact strength increased after immersion in water at each immersion temperature, and the extent of such increment decreased with increasing the immersion temperature. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2824–2832, 2002
Ganglionic eminence of the human fetal brain—new vistas
Authors: Ulfig Norbert 
Published: October 2002

AbstractThis review deals with recent findings concerning the complex functions of the ganglionic eminence (GE), which represents a conspicuous domain of the telencephalic proliferative zone and persists nearly throughout fetal life. The GE not only contains precursor neurons of the basal ganglia, it also contributes significantly to the population of interneurons in the cerebral cortex and to a population of thalamic neurons. The latter migrate through a distinct transient structure, the gangliothalamic body (GTB). The GE also represents an intermediate target for growing thalamic axons (on their way to the cerebral cortex) and cortical axons (on their way to the thalamus). In developmental neuropathology the GE plays an important role in prematurely born infants. The pathogenesis of GE bleedings is discussed with regard to the abundant expression of interleukin‐6 (IL‐6) receptors on GE cells. The consequences of such bleedings are discussed in view of cellular responses, such as the induction of leukemia inhibitory factor (LIF) expression in GE cells after hemorrhage. Anat Rec 267:191–195, 2002. © 2002 Wiley‐Liss, Inc.
Species‐specific differences of myosin content in the developing cardiac chambers of fish, birds, and mammals
Authors: Franco Diego , Gallego Alejandro , Habets Petra E.M.H. , Sans‐Coma V. , Moorman Antoon F.M. 
Published: October 2002

AbstractKey morphogenetic events during heart ontogenesis are similar in different vertebrate species. We report that in primitive vertebrates, i.e., cartilaginous fishes, both the embryonic and the adult heart show a segmental subdivision similar to that of the embryonic mammalian heart. Early morphogenetic events during cardiac development in the dogfish are long‐lasting, providing a suitable model to study changes in pattern of gene expression during these stages. We performed a comparative study among dogfish, chicken, rat, and mouse to assess whether species‐specific qualitative and/or quantitative differences in myosin heavy chain (MyHC) distribution arise during development, indicative of functional differences between species. MyHC RNA content was investigated by means of in situ hybridisation using an MyHC probe specific for a highly conserved domain, and MyHC protein content was assessed by immunohistochemistry. MyHC transcripts were found to be homogeneously distributed in the myocardium of the tubular and embryonic heart of dogfish and rodents. A difference between atrial and ventricular MyHC content (mRNA and protein) was observed in the adult stage. Interestingly, differences in the MyHC content were observed at the tubular heart stage in chicken. These differences in MyHC content illustrate the distinct developmental profiles of avian and mammalian species, which might be ascribed to distinct functional requirements of the myocardial segments during ontogenesis. The atrial myocardium showed the highest MyHC content in the adult heart of all species analysed (dogfish (S. canicula), mouse (M. musculus), rat (R. norvegicus), and chicken (G. gallus)). These observations indicate that in the adult heart of vertebrates the atrial myocardium contains more myosin than the ventricular myocardium. Anat Rec 268:27–37, 2002. © 2002 Wiley‐Liss, Inc.
Activation of the Sarcophaga lectin gene promoter in transgenic Drosophila
Authors: Tanji Takahiro , Kobayashi Ayako , Natori Shunji 
Published: October 2002

AbstractWe established transgenic Drosophila strains in which the lacZ gene was expressed under the control of the 5′‐upstream regulatory region of the Sarcophaga lectin gene promoter (3.1 kbp). The reporter gene was expressed in the fat bodies of the transgenic larvae when they were immunized by body pricking or treatment with Escherichia coli, which was the same as the Sarcophaga lectin gene expression in Sarcophaga larvae. However, the same reporter gene was found to be expressed constitutively in the digestive tracts of the transgenic larvae even without immunization. Arch. Insect Biochem. Physiol. 50:131–138, 2002. © 2002 Wiley‐Liss, Inc.
Inhibition of insulin‐like growth factor binding protein 5 proteolysis in articular cartilage and joint fluid results in enhanced concentrations of insulin‐like growth factor 1 and is associated with improved osteoarthritis
Authors: Clemmons David R. , Busby Walker H. , Garmong Aaron , Schultz Duane R. , Howell David S. , Altman Roy D. , Karr Robert 
Published: October 2002

AbstractObjectiveThe complement component C1s is present in dog joint fluid in an activated state. Since C1s degrades insulin‐like growth factor binding protein 5 (IGFBP‐5), we undertook to determine whether inhibiting C1s in joint fluid would result in an increase in the amount of intact IGFBP‐5 and IGF‐1 in cartilage and joint fluid, and whether C1s inhibition would be associated with a reduction in cartilage destruction during the development of osteoarthritis (OA).MethodsTwenty‐two dogs were randomized to 3 treatment groups. All dogs underwent anterior cruciate ligament transection and were exercised. Dogs received 1 of 3 treatments: buffer alone (controls; n = 6); PB‐145, a peptide derived from the sequence of antithrombin III (n = 9); and pentosan polysulfate (PPS; n = 7). PB‐145 or saline was injected into the joint space 3 times per week for 3 weeks. PPS was injected intramuscularly weekly for 3 weeks.ResultsJoint histology showed preservation of chondrocytes and a smooth joint surface in the animals treated with PB‐145 and PPS. Mankin scoring showed statistically significant reductions in joint destruction with PB‐145 and PPS treatments (P < 0.01) compared with buffer control. Mean active collagenase concentrations were decreased by these two treatments. Immunoblotting of joint fluid showed that both treatments increased concentrations of intact IGFBP‐5. Direct analysis of IGFBP‐3 and IGFBP‐5 protease activity showed that IGFBP‐5 was degraded more rapidly and that PB‐145 and PPS inhibited the degradation of both proteins. Total IGF‐1 concentrations in joint fluid were increased 5.6–5.8‐fold by these two treatments. Analysis showed that C1s was being activated in joint fluid and that its activation was inhibited by the addition of PB‐145 or PPS.ConclusionThe findings suggest that direct inhibition of the serine protease C1s results in increased concentrations of intact IGFBP‐5 and that proteolysis of IGFBP‐3 is also inhibited, probably by the inhibition of some other protease. This increase in concentrations of intact IGFBP‐3 and IGFBP‐5 leads to an increase in IGF‐1 which is associated with an improvement in joint architecture during the development of OA.
A serologic marker for fetal risk of congenital heart block
Authors: Salomonsson Stina , Dörner Thomas , Theander Elke , Bremme Katarina , Larsson Per , Wahren‐Herlenius Marie 
Published: October 2002

AbstractObjectiveTo analyze the humoral immune response to Ro/SSA and La/SSB antigens in detail, in order to identify markers in mothers at high risk of having children with congenital heart block (CHB).MethodsSerum samples were obtained from 9 Ro/La‐positive mothers who gave birth to affected children, from their 8 newborns with CHB, and from 26 Ro/La‐positive mothers whose children were healthy. Antibodies against Ro 52‐kd, Ro 60‐kd, and La were analyzed by enzyme‐linked immunosorbent assay and immunoblotting, using recombinant proteins and synthetic peptides.ResultsIgG anti‐Ro 52‐kd antibodies were detected in all mothers who gave birth to children with CHB, as well as in their affected children, but were less frequent and at lower levels in control mothers. Fine mapping revealed a striking difference in which the response in mothers with affected children was dominated by antibodies to amino acids 200–239 of the Ro 52‐kd protein (P = 0.0002), whereas the primary activity in control mothers was against amino acids 176–196 (P = 0.001). Furthermore, 8 of 9 mothers of children with CHB had antibody reactivity against amino acids 1–135 of the Ro 52‐kd protein, containing 2 putative zinc fingers reconstituted under reducing conditions.ConclusionThe results suggest that development of CHB is strongly dependent on a specific antibody profile to Ro 52‐kd, which may be a useful tool to identify pregnant Ro/La‐positive women at risk of delivering a baby with CHB. Close monitoring of mothers at high risk would enable early detection of a block that is still developing and allow early treatment to combat more serious complications.
Heterogeneity between men and women in the influence of the HLA–DRB1 shared epitope on the clinical expression of rheumatoid arthritis
Authors: del Rincón Inmaculada , Battafarano Daniel F. , Arroyo Ramón A. , Murphy Frederick T. , Escalante Agustín 
Published: October 2002

AbstractObjectiveTo test the hypothesis that the influence of the HLA–DRB1 shared epitope (SE) on the clinical manifestations of rheumatoid arthritis (RA) differs between men and women.MethodsWe assessed 777 consecutive RA patients for age at disease onset, articular manifestations, subcutaneous nodules, laboratory and radiographic findings, and treatment received. We typed HLA–DRB1 alleles by polymerase chain reaction–sequence‐specific primer amplification and categorized the number of SE‐containing alleles. We used regression models to adjust comparisons between the sexes for age and clustering by recruitment center, and included SE × sex interaction terms to look for heterogeneity between men and women in the effect of the SE.ResultsAmong the 777 RA patients, 548 (71%) were women. Men and women differed significantly in the adjusted frequency of SE positivity (women 71.4% versus men 78.4%;P≤ 0.001). The SE was associated with a younger age at symptom onset and RA diagnosis among men, but not among women. The SE likewise had a significant adverse effect on joint tenderness, swelling, and deformity among men only. The SE was associated with a higher erythrocyte sedimentation rate in women and more frequent positivity for rheumatoid factor among both men and women.ConclusionThere is heterogeneity between men and women in the effect of the SE on RA susceptibility and clinical expression. Further research is needed to understand the mechanism of this heterogeneity.
Pathologic indicators of degradation and inflammation in human osteoarthritic cartilage are abrogated by exposure to n‐3 fatty acids
Authors: Curtis Clare L. , Rees Sarah G. , Little Chris B. , Flannery Carl R. , Hughes Clare E. , Wilson Chris , Dent Colin M. , Otterness Ivan G. , Harwood John L. , Caterson Bruce 
Published: October 2002

AbstractObjectiveTo determine if n‐3 polyunsaturated fatty acid (PUFA) supplementation (versus treatment with n‐6 polyunsaturated or other fatty acid supplements) affects the metabolism of osteoarthritic (OA) cartilage.MethodsThe metabolic profile of human OA cartilage was determined at the time of harvest and after 24‐hour exposure to n‐3 PUFAs or other classes of fatty acids, followed by explant culture for 4 days in the presence or absence of interleukin‐1 (IL‐1). Parameters measured were glycosaminoglycan release, aggrecanase and matrix metalloproteinase (MMP) activity, and the levels of expression of messenger RNA (mRNA) for mediators of inflammation, aggrecanases, MMPs, and their natural tissue inhibitors (tissue inhibitors of metalloproteinases [TIMPs]).ResultsSupplementation with n‐3 PUFA (but not other fatty acids) reduced, in a dose‐dependent manner, the endogenous and IL‐1–induced release of proteoglycan metabolites from articular cartilage explants and specifically abolished endogenous aggrecanase and collagenase proteolytic activity. Similarly, expression of mRNA for ADAMTS‐4, MMP‐13, and MMP‐3 (but not TIMP‐1, ‐2, or ‐3) was also specifically abolished with n‐3 PUFA supplementation. In addition, n‐3 PUFA supplementation abolished the expression of mRNA for mediators of inflammation (cyclooxygenase 2, 5‐lipoxygenase, 5‐lipoxygenase–activating protein, tumor necrosis factor α, IL‐1α, and IL‐1β) without affecting the expression of message for several other proteins involved in normal tissue homeostasis.ConclusionThese studies show that the pathologic indicators manifested in human OA cartilage can be significantly altered by exposure of the cartilage to n‐3 PUFA, but not to other classes of fatty acids.
Fenofibrate inhibits reactive amyloidosis in mice
Authors: Murai Takehiro , Yamada Toshiyuki , Miida Takashi , Arai Katsumitsu , Endo Naoto , Hanyu Tadamasa 
Published: October 2002

AbstractObjectiveTo examine the effects of the lipid‐lowering agent fenofibrate on experimental AA amyloidosis and on serum amyloid A (SAA) levels.MethodsFenofibrate was administered orally in a mouse model of amyloidosis, which is induced by injections of amyloid‐enhancing factor and Freund's complete adjuvant. Fenofibrate was given for 3 weeks, including a 1‐week course before induction of amyloidosis. Splenic amyloid deposits were evaluated histologically, and SAA levels were measured.ResultsFenofibrate inhibited the formation of splenic amyloid deposits and suppressed the elevation of SAA levels.ConclusionFenofibrate inhibits experimental amyloidosis by reducing levels of the precursor SAA.
A gene in the telomeric HLA complex distinct from HLA–A is involved in predisposition to juvenile idiopathic arthritis
Authors: Smerdel Anna , Lie Benedicte A. , Ploski Rafal , Koeleman Bobby P. C. , Førre Øystein , Thorsby Erik , Undlien Dag E. 
Published: October 2002

AbstractObjectiveJuvenile idiopathic arthritis (JIA) is associated with particular alleles at 3 different HLA loci: HLA–A, HLA–DR/DQ, and HLA–DP. These associations are independent of each other (i.e., they cannot be explained by the known linkage disequilibrium between alleles at these loci). The purpose of this study was to look for additional JIA susceptibility genes in the HLA complex.MethodsOne hundred two Norwegian JIA patients and 270 healthy individuals, all carrying the DQ4;DR8 haplotype, were investigated by scanning ∼10 megabases of DNA covering the HLA complex with microsatellite polymorphisms. An expectation‐maximization algorithm was used to estimate haplotype frequencies, and the distribution of microsatellite alleles on the high‐risk DQ4;DR8 haplotype was compared between patients and controls, to exclude effects secondary to linkage disequilibrium with these susceptibility genes.ResultsAllele 5 at the microsatellite locus D6S265 (D6S265* 5), 100 kb centromeric of HLA–A, showed a strong positive association with the disease (odds ratio 4.7, corrected P < 10−6). Haplotype analysis demonstrated that the D6S265*5 association was not caused by linkage disequilibrium to the gene encoding HLA–A*02, which has previously been reported to be associated with JIA. Instead, our data suggested that a gene in linkage disequilibrium with D6S265*5, but distinct from HLA–A*02, is involved in the predisposition to JIA.ConclusionWe found that D6S265*5 could be a marker for an additional susceptibility gene in JIA which is distinct from A*02, adding to the risk conferred by DQ4;DR8.
Autoantibodies to fibroblasts induce a proadhesive and proinflammatory fibroblast phenotype in patients with systemic sclerosis
Authors: Chizzolini Carlo , Raschi Elena , Rezzonico Roger , Testoni Cinzia , Mallone Roberto , Gabrielli Armando , Facchini Andrea , Del Papa Nicoletta , Borghi Maria Orietta , Dayer Jean Michel , Meroni Pier Luigi 
Published: October 2002

AbstractObjectiveFibroblasts play a major role in the development of systemic sclerosis (SSc), and the occurrence of serum autoantibodies reacting with fibroblast plasma membrane antigens in SSc has been reported. This study was undertaken to investigate whether IgG from SSc sera that react with human fibroblasts modulates the fibroblasts' function.MethodsSera from 69 patients with SSc (28 with limited cutaneous SSc [lcSSc] and 41 with diffuse cutaneous SSc [dcSSc]), 30 patients with sarcoidosis, and 50 matched healthy controls were examined. We evaluated antibody binding to human skin and lung fibroblasts by cell‐based enzyme‐linked immunosorbent assay (ELISA), indirect immunofluorescence, and flow cytometry. We further investigated the ability of purified IgG to modulate 1) intercellular adhesion molecule 1 (ICAM‐1) expression, 2) U937 cell adhesion to fibroblasts, and 3) fibroblast steady‐state messenger RNA (mRNA) levels of interleukin‐1α (IL‐1α), IL‐β, and IL‐6, and IL‐6 protein production.ResultsOf 69 SSc sera tested by cell‐based ELISA, 58% bound to normal skin and lung fibroblasts. The prevalence of binding was significantly higher in dcSSc than in lcSSc (P < 0.05). Only IgG from SSc sera that were positive for antifibroblast antibody (AFA) induced a dose‐dependent up‐regulation of ICAM‐1 expression and IL‐6 production, enhancement of U937 cell adhesion, and increased levels of IL‐1α, IL‐1β, and IL‐6 mRNA in fibroblasts. Up‐regulation of ICAM‐1 mediated by AFA IgG was inhibited by the addition of IL‐1 receptor antagonist, indicating an autocrine activation loop.ConclusionOur findings confirm the presence of AFAs in SSc sera and demonstrate, for the first time, that autoantibodies reacting with fibroblast surface molecules act as an extrinsic stimulus inducing fibroblast activation in vitro.
Polysaccharide–polynucleotide complexes VIII. Cation‐induced complex formation between polyuridylic acid and schizophyllan
Authors: Sakurai Kazuo , Iguchi Ritsuko , Koumoto Kazuya , Kimura Taro , Mizu Masami , Hisaeda Yoshio , Shinkai Seiji 
Published: October 2002

AbstractSchizophyllan belongs to the β‐1,3‐D‐glucan family, and dissolves as a single chain in dimethyl sulfoxide (DMSO) and as a triple helix in water, respectively. It is already known that when we prepare a mixture of poly(C) and schizophyllan in DMSO and subsequently exchange the solvent to water, poly(C) and schizophyllan can form a complex. When we applied this procedure to the poly(U) system, we could not induce the complex formation between poly(U) and schizophyllan at all. However, we found that addition of some alkaline cations is necessary to induce the complexation between poly(U) and schizophyllan. The complex stability strongly depends on both the cation species and the salt concentration. The complexation is sensitively reflected in the CD spectrum. The magnitude of the spectral change is followed by the order; Rb+ ≫ K+ > Na+ ? Cs+. This cation order in the stability is confirmed by the fluorescence polarization measurements. 23Na‐NMR spectroscopy reveals that the product system is stabilized by addition of the cations, suggesting that the OH group in schizophyllan and the phosphate anion in poly(U) synergistically form a specific ligand system for the cations. To the best of our knowledge, such a cation‐induced specific interaction between saccharides and polynucleotides has not been reported, and may provide a new clue to understand the biological role of β‐1,3‐D‐glucans. © 2002 Wiley Periodicals, Inc. Biopolymers 65: 1–9, 2002