bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibitory effect of diazepam on muscarinic receptor‐stimulated inositol 1,4,5‐trisphosphate production in rat parotid acinar cells
Authors: Kujirai Masao , Sawaki Kohei , Kawaguchi Mitsuru 
Published: November 2002

This study examined the effect of diazepam (DZP) on phosphoinositide turnover, which plays an important role in the regulation of salivary secretion, in rat parotid acinar cells.
DZP (10−9 M to 10−5 M), a potent agonist of both central‐ and peripheral‐type benzodiazepine receptors, dose‐dependently decreased inositol 1,4,5‐trisphosphate (IP3) production stimulated by carbachol, a muscarinic receptor agonist, in the cells.
DZP produced a maximum inhibitory response at a concentration of 10−5 M, with IP3 production decreased to 63% of maximal levels. The concentration inducing half maximal inhibition of IP3 production was approximately 3.5×10−8 M.
An inhibitory response to DZP was produced by a short‐term pretreatment (<3 min) of the cells and prevented by antagonist and competing ligand for the central‐ and peripheral‐type benzodiazepine receptors, flumazenil and PK 11195, respectively.
DZP showed a non‐competitive inhibition of carbachol‐stimulated IP3 production. It did not directly inhibit the activities of GTP‐binding regulatory proteins and phosphatidylinositol 4,5‐bisphosphate‐specific phospholipase C (PLC) in the parotid gland membranes, though choline chloride inhibited PLC activity.
DZP (10−5 M) attenuated the increase in the intracellular Ca2+ concentration ([Ca2+]i) in the cells following stimulation of the muscarinic and α1‐adrenoceptors.
These results suggest that in the parotid acinar cells, DZP inhibits muscarinic receptor‐stimulated IP3 production through benzodiazepine receptors and that PLC activity which produces IP3 is inhibited by chloride. The decreases in IP3 and [Ca2+]i in the cells may be connected with the suppression of salivary secretion induced by DZP.

British Journal of Pharmacology (2002) 137, 945–952. doi:10.1038/sj.bjp.0704968
Clinical benefit of joint distraction in the treatment of severe osteoarthritis of the ankle: Proof of concept in an open prospective study and in a randomized controlled study
Authors: Marijnissen Anne C. A. , Van Roermund Peter M. , Van Melkebeek Jan , Schenk Willem , Verbout Abraham J. , Bijlsma Johannes W. J. , Lafeber Floris P. J. G. 
Published: November 2002

AbstractObjectiveOsteoarthritis (OA) is a degenerative, disabling joint disease that affects >10% of the adult population. No effective disease‐modifying treatment is available. In the present study, we used joint distraction, a relatively new treatment in which mechanical contact between the articular surfaces is avoided while intraarticular intermittent fluid pressure is maintained, to treat patients with severe OA of the ankle.MethodsPatients with severe ankle OA (n = 57) who were being considered for joint fusion (arthrodesis) were treated with joint distraction in an open prospective study. In addition, a randomized trial was performed in 17 patients to determine whether joint distraction had a better outcome than debridement. A standardized evaluation protocol (physical examination, assessment of pain, mobility, and functional ability) was used, and changes in radiographic joint space width and subchondral sclerosis were measured. Thirty‐eight patients in the open study have been followed up for >1 year, with up to 5 years of followup in 7 of them (mean ± SD followup 2.8 ± 0.3 years). Patients in the randomized study have been followed up for 1 year.ResultsSignificant clinical benefit was found in three‐fourths of the 57 patients in the open prospective study. Most interestingly, the improvement increased over time. Radiographic evaluation showed increased joint space width and decreased subchondral sclerosis. Moreover, joint distraction showed significantly better results than debridement.ConclusionThe clinical benefit of joint distraction in the treatment of severe OA is proof of the concept. Although the followup remains relatively short and effects over time remain unpredictable, our study creates possibilities for the treatment of severe OA in general. Considering the high prevalence of OA and the lack of a cure for it, joint distraction as a treatment of severe OA may have great medical, social, and economic impact.
Transforming growth factor β induces fibroblast fibrillin‐1 matrix formation
Authors: Kissin Eugene Y. , Lemaire Raphael , Korn Joseph H. , Lafyatis Robert 
Published: November 2002

AbstractObjectiveFibrillin, an extracellular matrix protein implicated in dermal fibrosis, is increased in the reticular dermis of systemic sclerosis (SSc) skin. We undertook this study to investigate the hypothesis that transforming growth factor β (TGFβ) or other cytokines regulate fibrillin matrix formation by normal and SSc fibroblasts. We further investigated the mechanism of TGFβ‐induced fibrillin fibrillogenesis and its relationship to myofibroblasts.MethodsFibrillin and fibronectin matrix deposition and α‐smooth muscle actin expression by fibroblast cultures from normal and SSc skin treated with TGFβ or other cytokines were analyzed by immunofluorescence. Supernatant and extracellular matrix from normal and SSc fibroblasts treated with or without TGFβ were evaluated by Western blot and Northern blot for fibrillin protein and messenger RNA (mRNA) expression, respectively.ResultsImmunofluorescence demonstrated increased fibrillin matrix formation by normal and scleroderma fibroblasts after TGFβ treatment. Other cytokines, including tumor necrosis factor α, interleukin‐1β (IL‐1β), IL‐4, granulocyte–macrophage colony‐stimulating factor, and platelet‐derived growth factor, did not affect fibrillin fibrillogenesis. Fibrillin matrix formed in proximity to myofibroblasts and independently of up‐regulation of fibronectin matrix or cell number. Western blot analysis of extracellular matrix confirmed increased fibrillin after TGFβ stimulation of normal or scleroderma fibroblasts. However, TGFβ did not alter the expression of either soluble fibrillin protein or fibrillin mRNA.ConclusionOur data show that TGFβ induces fibrillin protein incorporation into the extracellular matrix without affecting fibrillin gene expression or protein synthesis, suggesting that fibrillin matrix assembly is regulated extracellularly. TGFβ might increase fibrillin matrix by activating myofibroblasts. Such TGFβ‐mediated effects could account for the increased fibrillin matrix observed in SSc skin.
Determining the molecular weight, aggregation, structures and interactions of natural organic matter using diffusion ordered spectroscopy
Authors: Simpson André J. 
Published: November 2002

AbstractDiffusion ordered spectroscopy (DOSY) was applied to examine the chemical and physical properties of soil organic matter, a complex natural mixture. Soil organic matter extracts are often termed humic substances (HS), which traditionally have been thought to be high molecular weight, cross‐linked macromolecules with undetermined structures. Separation of the components in the studied humic acid (HA) clearly indicates that the HS studied here are pseudo‐high molecular weight materials only, and associations or aggregates of molecules of smaller molecular sizes, which can be disrupted with organic acids. At high concentration, these aggregates display diffusivities that are consistent with those observed in large proteins (>66 kDa). After disaggregation and at low concentration, DOSY NMR reveals components that have chemical shifts that are consistent with lignins, polysaccharides and peptides, and have diffusivities consistent with molecular weights of ∼2500, ∼1000 and 200–600 Da, respectively. Diffusion studies of fulvic acids (FA) indicate that little if any aggregation occurs in solution and that, on average, the components display diffusivities that are consistent with molecules that have relatively low molecular weights of ∼1000 Da. However, in addition to a range of small molecular components, DOSY NMR reveals for the first time direct evidence that larger molecular weight components also exist within the mixtures. In an FA isolated from the surface soil of an oak forest, large polysaccharides with average diffusivities similar to 6000 Da maltodextrins can be identified. In an FA from an agricultural soil, components consistent with peptides/proteins are identified that have aggregate/molecular sizes in the region of 12 000 Da. It is logical that an operationally defined extract of soils will result in a mixture of plant components at various stages of humification with a range of molecular sizes and structures rather than macromolecules with undetermined structures. In addition to advancing our structural understanding of natural organic matter (NOM), DOSY provides potential to study the interactions of these mixtures with contaminants. This paper explorers the interaction of a HA with two organic contaminants (MTBE and chlorsulfuron) and an FA with cadmium. Diffusion measurements show that MTBE has a weaker interaction with the organic materials than chlorsulfuron. Studies with cadmium suggest that the metal exhibits dynamic exchange which is fast on the NMR time‐scale. Such findings have strong implications for understanding the behavior and toxicity of cadmium in the environment. Although cadmium has an affinity for NOM, it is clear that it is not irreversibly bound and may be bioavailable under many conditions. Copyright © 2002 John Wiley & Sons, Ltd.
Monitoring the non‐specific interactions of catechin through diffusion measurements based on pulsed‐field gradients
Authors: Monteiro C. , Maechling C. , Hervé du Penhoat C. 
Published: November 2002

AbstractThe self‐association of aqueous catechin as a function of concentration was monitored through variations in 1H chemical shifts, proton T1 and T2 data and translational diffusion coefficients obtained with the pulsed‐field gradient spin‐echo method. The latter approach is very efficient and it is not restricted to aromatic compounds. Equilibrium constants were estimated for various models of self‐association and the apparent enthalpy of dissociation was measured with isothermal titration calorimetry. Comparison of the latter parameter with thermodynamic data reported for various types of non‐specific interactions suggests that such phenomena could be studied using this approach. Copyright © 2002 John Wiley & Sons, Ltd.
PGSE NMR diffusion study of the self‐association of N‐methylacetamide in carbon tetrachloride
Authors: Regan David G. , Chapman Bogdan E. , Kuchel Philip W. 
Published: November 2002

AbstractN‐Methylacetamide (NMA) is known to self‐associate in solution through the formation of hydrogen bonds. This behavior, and the presence in the molecule of an amide bond, make this an interesting model for study since the oligomer can be considered to be a protein analogue. The aims of the present study were to estimate the thermodynamic parameters of the self‐association process, through the measurement of the diffusion coefficient of NMA in carbon tetrachloride (CCl4), and to predict the population distribution of oligomers as a function of the concentration of NMA. Diffusion coefficients were measured using pulsed field gradient spin‐echo (PGSE) NMR spectroscopy. A computer model based on the Kirkwood–Riseman theory of macromolecular diffusion and an attenuative model of self‐association were used to fit the experimental data and to derive estimates of the thermodynamic association constants and bond length, and these values were, in turn, used to estimate the oligomer distribution. In addition, the temperature dependence of the diffusion coefficient was measured at three different concentrations in order to calculate the apparent Arrhenius activation energies so as to provide additional insight into the self‐association process. Finally, the concentration dependence of the viscosity of NMA in CCl4 was measured to characterize further the hydrodynamic behavior of the polydisperse system. Copyright © 2002 John Wiley & Sons, Ltd.
The steady propagation of a semi-infinite bubble
into a tube of elliptical or rectangular
cross-section
Authors: HAZEL ANDREW L. , HEIL MATTHIAS 
Published: November 2002

This paper investigates the propagation of an air finger into a fluid-filled, axially
uniform tube of elliptical or rectangular cross-section with transverse length scale a
and aspect ratio α. Gravity is assumed to act parallel to the tube's axis. The problem
is studied numerically by a finite-element-based direct solution of the free-surface
Stokes equations.In rectangular tubes, our results for the pressure drop across the bubble tip, Δp,
are in good agreement with the asymptotic predictions of Wong et al. (1995b) at
low values of the capillary number, Ca (ratio of viscous to surface-tension forces).
At larger Ca, Wong et al.'s (1995b) predictions are found to underestimate Δp. In
both elliptical and rectangular tubes, the ratio Δp(α)/Δp(α = 1) is approximately
independent of Ca and thus equal to the ratio of the static meniscus curvatures.In non-axisymmetric tubes, the air-liquid interface develops a noticeable asymmetry
near the bubble tip at all values of the capillary number. The tip asymmetry decays
with increasing distance from the bubble tip, but the decay rate becomes very small
as Ca increases. For example, in a rectangular tube with α = 1.5, when Ca = 10, the
maximum and minimum finger radii still differ by more than 10% at a distance 100a
behind the finger tip. At large Ca the air finger ultimately becomes axisymmetric with
radius r∞. In this regime, we find that r∞ in elliptical and rectangular tubes is related
to r∞ in circular and square tubes, respectively, by a simple, empirical scaling law. The scaling has the physical interpretation that for rectangular and elliptical tubes of
a given cross-sectional area, the propagation speed of an air finger, which is driven by
the injection of air at a constant volumetric rate, is independent of the tube's aspect
ratio.For smaller Ca (Ca <
Ca), the air finger is always non-axisymmetric and the
persisting draining flows in the thin film regions far behind the bubble tip ultimately
lead to dry regions on the tube wall.
Ca increases with increasing α and for α > αˆ
dry spots will develop on the tube walls at all values of Ca.
Effects of non‐steroidal anti‐inflammatory drugs on cyclo‐oxygenase and lipoxygenase activity in whole blood from aspirin‐sensitive asthmatics vs healthy donors
Authors: Gray P A , Warner T D , Vojnovic I , Del Soldato P , Parikh A , Scadding G K , Mitchell J A 
Published: November 2002

Cyclo‐oxygenase (COX) and lipoxygenase (LO) share a common substrate, arachidonic acid. Aspirin and related drugs inhibit COX activity. In a subset of patients with asthma aspirin induces clinical symptoms associated with increased levels of certain LO products, a phenomenon known as aspirin‐sensitive asthma. The pharmacological pathways regulating such responses are not known.
Here COX‐1 and LO activity were measured respectively by the formation of thromboxane B2 (TXB2) or leukotrienes (LT) C4, D4 and E4 in whole blood stimulated with A23187. COX‐2 activity was measured by the formation of prostaglandin E2 (PGE2) in blood stimulated with lipopolysaccharide (LPS) for 18 h.
No differences in the levels of COX‐1, COX‐2 or LO products or the potency of drugs were found in blood from aspirin sensitive vs aspirin tolerant patients. Aspirin, indomethacin and nimesulide inhibited COX‐1 activity, without altering LO activity. Indomethacin, nimesulide and the COX‐2 selective inhibitor DFP [5,5‐dimethyl‐3‐(2‐isopropoxy)‐4‐(4‐methanesulfonylphenyl)‐2(5H)‐furanone] inhibited COX‐2 activity. NO‐aspirin, like aspirin inhibited COX‐1 activity in blood from both groups. However, NO‐aspirin also reduced LO activity in the blood from both patient groups. Sodium salicylate was an ineffective inhibitor of COX‐1, COX‐2 or LO activity in blood from both aspirin‐sensitive and tolerant patients.
Thus, when COX activity in the blood of aspirin‐sensitive asthmatics is blocked there is no associated increase in LO products. Moreover, NO‐aspirin, unlike other NSAIDs tested, inhibited LO activity in the blood from both aspirin sensitive and aspirin tolerant individuals. This suggests that NO‐aspirin may be better tolerated than aspirin by aspirin‐sensitive asthmatics.

British Journal of Pharmacology (2002) 137, 1031–1038. doi:10.1038/sj.bjp.0704927
Investigation of thin surface‐wetting films in two‐phase saturated porous media
Authors: Holmes William M. , Packer Ken J. 
Published: November 2002

AbstractStrongly water‐wet porous solids were saturated with two immiscible phases, an aqueous and an hydrocarbon phase, in varying proportions. The porous solids studied were a sample of Fontainebleau sandstone and packs of monodisperse glass beads. The diffusive displacements of the aqueous phase (i.e. the wetting phase) were investigated using pulsed field gradient stimulated echo (PGSTE) NMR to measure the one‐dimensional displacement probability distribution PΔ(X). Measurements of PΔ(X) are presented for the whole accessible water saturation range. At lower water contents the displacement distributions PΔ(X) show a distinctive shape, which is attributed to the distribution of the aqueous phase in thin surface wetting films connecting pendular rings where the beads are in contact. The data are reproduced well by a random walk computer model based on such a geometry, the simulated propagators being very sensitive to the surface film thickness. The longitudinal relaxation times of the water phase were also measured and found to deviate from the fast diffusion model at low water saturations. Copyright © 2002 John Wiley & Sons, Ltd.
After‐hours trading of NYSE stocks on the regional stock exchanges
Authors: McInish Thomas H , Van Ness Bonnie F , Van Ness Robert A 
Published: November 2002

AbstractA large number of New York Stock Exchange (NYSE)‐listed stocks are traded on the Chicago, Philadelphia, and Pacific exchanges, and these exchanges have extended their trading hours to permit trading in NYSE‐listed stocks after the close of trading on the NYSE. Demand for after‐hours trading on the regional exchanges is limited. The Pacific Stock Exchange, which transacts less than 40% of the combined regionals' trading volume during regular trading hours, captures more than 63% of the after‐hours trades. We find that there is very little price discovery during after‐hours trading. Almost all of the trades take place at either the NYSE closing ask, bid, or trade price. The most actively traded stocks intraday also tend to be the most actively traded stocks after hours. The percentage spreads and percentage half‐spreads are significantly higher during the after‐hours sessions on all three regional exchanges. Among the Chicago, Philadelphia, and Pacific exchanges, spreads are significantly lower after‐hours on the Pacific exchange at the .10 level. Depth declines significantly during after‐hours trading on the Chicago and Philadelphia exchanges and increases significantly on the Pacific exchange.
Differential peristaltic motor effects of prostanoid (DP, EP, IP, TP) and leukotriene receptor agonists in the guinea‐pig isolated small intestine
Authors: Shahbazian Anaid , Heinemann Akos , Peskar Bernhard A , Holzer Peter 
Published: November 2002

Since the role of prostanoid receptors in intestinal peristalsis is largely unknown, the peristaltic motor effects of some prostaglandin (DP, EP, IP), thromboxane (TP) and leukotriene (LT) receptor agonists and antagonists were investigated.
Propulsive peristalsis in fluid‐perfused segments from the guinea‐pig small intestine was triggered by a rise of the intraluminal pressure and recorded via the intraluminal pressure changes associated with the peristaltic waves. Alterations of distension sensitivity were deduced from alterations of the peristaltic pressure threshold and modifications of peristaltic performance were reflected by modifications of the amplitude, maximal acceleration and residual baseline pressure of the peristaltic waves.
Four categories of peristaltic motor effects became apparent: a decrease in distension sensitivity and peristaltic performance as induced by the EP1/EP3 receptor agonist sulprostone and the TP receptor agonist U‐46,619 (1–1000 nM); a decrease in distension sensitivity without a major change in peristaltic performance as induced by PGD2 (3–300 nM) and LTD4 (10–100 nM); a decrease in peristaltic performance without a major change in distension sensitivity as induced by PGE1, PGE2 (1–1000 nM) and the EP1/IP receptor agonist iloprost (1–100 nM); and a decrease in peristaltic performance associated with an increase in distension sensitivity as induced by the EP2 receptor agonist butaprost (1–1000 nM). The DP receptor agonist BW‐245C (1–1000 nM) was without effect.
The peristaltic motor action of sulprostone remained unchanged by the EP1 receptor antagonist SC‐51,089 (1 μM) and the DP/EP1/EP2 receptor antagonist AH‐6809 (30 μM), whereas that of U‐46,619 and LTD4 was prevented by the TP receptor antagonist SQ‐29,548 (10 μM) and the cysteinyl‐leukotriene1 (cysLT1) receptor antagonist tomelukast (10 μM), respectively.
These observations and their pharmacological analysis indicate that activation of EP2, EP3, IP, TP and cysLT1 receptors, but not DP receptors, modulate intestinal peristalsis in a receptor‐selective manner, whereas activation of EP1 seems to be without influence on propulsive peristalsis. In a wider perspective it appears as if the effect of prostanoid receptor agonists to induce diarrhoea is due to their prosecretory but not peristaltic motor action.

British Journal of Pharmacology (2002) 137, 1047–1054. doi:10.1038/sj.bjp.0704958
Relaciones afectivas y satisfaccion sexual en la pareja
Authors: Fuertes Antonio 
Published: November 2002

Con objeto de analizar la asociación entre las relaciones afectivas y la satisfacción sexual, setenta y una parejas completaron tres diferentes formatos adaptados de la Escala de Amor de Rubin (1970, 73), así como el Inventario de Interacción Sexual de LoPiccolo y Steger (1974). Los resultados obtenidos indican que, mientras que en las parejas que no tienen hijos, los sentimientos de intimidad de la mujer (confianza, preocupación percibida en el otro), y la dependencia afectiva que el hombre percibe en su pareja, son las dimensiones que mayor asociación mantienen con la satisfacción sexual, en las parejas que tienen hijos, es la forma en que el hombre percibe y vivencia las relaciones afectivas lo que mantiene una relación más importante con la satisfacción sexual.
Por qué las mujeres se consideran más o menos femeninas y los hombres más o menos masculinos. Explicaciones sobre su autoconcepto de identidad de género
Authors: López-Zafra Esther , López-Sáez Mercedes 
Published: November 2002

El autoconcepto de feminidad en las mujeres y el de masculinidad en los hombres es considerado, por algunos autores, como una medida de identidad de género más idónea que la basada en la autoasignación de rasgos de personalidad expresivo-comunalese instrumental-agentes. El objetivo de este trabajo es analizar qué tipo de explicaciones dan mujeres y hombres sobre su autoevaluación como más o menos femeninas o más o menos masculinos, respectivamente. En el análisis del contenido de las respuestas abiertas de los 516 participantes se han tenido en cuenta el sexo, la edad y la saliencia del género como variables de control. Los resultados sugieren que existe una relación negativa entre el sentimiento de feminidad y el de masculinidad, tanto en hombres como en mujeres. Se comprueba que las personas altas en identidad de género utilizan sobre todo explicaciones basadas en los estereotipos, mientras que las personas bajas en identidad de género aluden más a explicaciones idiosincrásicas. Los hombres utilizan más que las mujeres explicaciones basadas en lo biológico como definitorias de la identidad de género. Se observa mayor proporción de respuestas basadas en los estereotipos entre las personas más jóvenes. No se han encontrado diferencias en función de la saliencia.