bluuebunny/crossref_metadata_2025 huggingface dataset:
Tendencias emergentes en el comportamiento de ocio: el ocio serio y su evaluación
Authors: Codina Núria
Published: November 2002

Se considera la expresión personal como una tendencia de comportamiento asociada a los cambios que experimentan las sociedades industriales avanzadas. Se analiza esta tendencia en el ámbito del ocio y, a falta de planteamientos más específicos, se muestra que ésta puede explicarse a partir de una teoría formulada recientemente con otros objetivos, la del ocio serio de Stebbins. Con base en ésta, observamos que numerosas actividades pueden darse como ocios serios y que el actual comportamiento en el ocio globalmente tiende a colorearse de cierto carácter serio, de manera que presenta el aspecto borroso de los sistemas complejos.

También observamos que se valora positivamente el ocio serio a partir de su estudio en el “aquí y ahora” y a través de la percepción subjetiva. Cuestionamos estas valoraciones mostrando que para avanzar en el conocimiento y evaluación psicosocial del ocio, especialmente del ocio serio, debe considerarse el carácter multiforme, ambivalente y transitorio del fenómeno en relación con el contexto sociocultural, así como las variables analíticas del ocio. Finalmente, explicamos que el consumo de un ocio serio puede derivar en un ocio consumidor, con consecuencias negativas para la persona y su entorno.
Cambios en la valoración del trabajo en jóvenes de primer empleo durante el proceso de socialización laboral
Authors: Gracia Francisco Javier , Rodríguez Isabel , Prieto Fernando
Published: November 2002

El trabajo es una de las áreas más importantes en la vida para los seres humanos y un pilar básico en el funcionamiento de cualquier sociedad. El significado que la gente da al trabajo, y qué aspectos son valorados del mismo, ha sido y es un tema de gran interés para los científicos sociales. Dos dimensiones principales del significado del trabajo son «los resultados valorados del trabajo» y la «importancia de metas laborales». «Los resultados valorados del trabajo» son aquellos resultados que el individuo busca del trabjar o qué funciones le son servidas a través del trabajo. «La importancia de metas laborales» se refiere a la importancia que tiene para los individuos determinados aspectos del trabajo. El objetivo de este trabajo es estudiar los cambios que se han producido en los valores laborales de los jóvenes durante sus primeros años de empleo. Nuestras hipótesis son que habrán tenido lugar cambios en los valores laborales de los jóvenes empleados y que una variable relevante para explicar dichos cambios serán los eventos o cambios que los sujetos hayan experimentado en su trabajo (p.e. cambios de puesto, cambios de nivel jerárquico, de empresa, de sector industrial y de situación de empleo/desempleo). Los resultados suponen un apoyo a la tesis interaccionista (Drenth, 1991) sobre el controvertido tema de la estabilidad del significado del trabajo.
A percepção da causalidade subjacente aos resultados desportivos e a idade dos atletas
Authors: Fonseca António Manuel
Published: November 2002

O principal objectivo deste estudo consistiu em analisar o modo como atletas de diferentes idades percepcionavam as competições em que estavam envolvidos, fundamentalmente no que se relacionava com as causas que consideravam ter estado subjacentes aos seus resultados desportivos. Para a sua realização contribuiu não só a escassez de investigações desenvolvidas sobre este assunto, das relações existentes entre a idade dos indivíduos e as atribuições que elaborampara os acontecimentos que protagonizam, mas também a inconsistência verificada entre as suas conclusõses. A amostra foi constituida por 270 atletas masculinos e femininos que competiam nos campeonatos nacionais de diversos desportos (natação, voleibol, ginástica artística e ginástica rítmica desportiva), e as suas idades estavam compreendidas entre os 10 e os 24 anos. Os atletas, para além de responderem a questoes de ordem demográfica (e.g., sexo, idade, tempo de prática desportiva anterior), responderam ainda a diversas questões sobre as competições em que tinham alcançado os resultados mais significativos das suas carreiras desportivas. As questões incidiam não só sobre as provas e os resultados obtidos mas também sobre as causas que eles consideravam mais ter contribuído para a sua obtenção. Para avaliarem as causas que indicaram, os atletas responderam a uma versao traduzida e adaptada (Fonseca, 1992, 1993) da Causal Dimension Scale II ( CDSII: McAuley et al., 1992). Os resultados evidenciaram que os atletas mais novos consideravam as causas dos seus resultados como mais internas, estáveis, e controláveis—por eles e não pelos outros—do que os seus colegas mais velhos. As respostas dos atletas dos diferentes grupos etários pareceram, no entanto, convergir num sentido: o da existência de um mecanismo de protecção ou implementação da sua auto-estima. Esta atitude, porém, pareceu assumir proporções diferenciadas para os atletas dos diferentes grupos etários.
Self epitopes shared between human skeletal myosin and Streptococcus pyogenes M5 protein are targets of immune responses in active juvenile dermatomyositis
Authors: Massa Margherita , Costouros Nick , Mazzoli Federica , De Benedetti Fabrizio , La Cava Antonio , Le Tho , de Kleer Isme , Ravelli Angelo , Liotta Margaret , Roord Sarah , Berry Charles , Pachman Lauren M. , Martini Alberto , Albani Salvatore
Published: November 2002

Objective

To identify self T cell epitopes associated with proinflammatory immune responses and clinically active juvenile dermatomyositis (juvenile DM). The target of our search for relevant epitopes was represented by amino acid sequences shared between human skeletal myosin and Streptococcus pyogenes M5 protein. The long‐term objective of the project is to identify suitable targets for immunotherapy of the disease.

Methods

We used computerized algorithms to identify putative agretopes on both the human myosin and Streptococcus M5 proteins. Direct binding assays for homolog peptides were used to confirm such predictions. Antigenicity and functional cross‐reactivity were evaluated by cytotoxicity assays and by measurement of cytokine levels. Specific T cells were isolated by T cell capture, and T cell receptor (TCR) Vβ gene usage was identified by reverse transcriptase–polymerase chain reaction.

Results

We identified peptides that are targets of disease‐specific cytotoxic T cell responses. T cell reactivity against the self peptides correlates with clinical signs of early, active myositis. Such reactivity is accompanied by production of proinflammatory cytokines, which may contribute to the damage. T cell cross‐recognition of bacterial and human homologs was shown functionally as well as by sorting peptide‐specific T cells and identifying oligoclonal and largely overlapping TCR Vβ gene usage.

Conclusion

These findings represent the first identification of a self epitope in juvenile DM, providing a potential candidate for antigen‐specific immune therapy.
Risk factors for progressive cartilage loss in the knee
Authors: Biswal Sandip , Hastie Trevor , Andriacchi Thomas P. , Bergman Gabrielle A. , Dillingham Michael F. , Lang Philipp
Published: November 2002

Objective

To evaluate the rate of progression of cartilage loss in the knee joint using magnetic resonance imaging (MRI) and to evaluate potential risk factors for more rapid cartilage loss.

Methods

We evaluated baseline and followup MRIs of the knees in 43 patients (minimum time interval of 1 year, mean 1.8 years, range 52–285 weeks). Cartilage loss was graded in the anterior, central, and posterior regions of the medial and lateral knee compartments. Knee joints were also evaluated for other pathology. Data were analyzed using analysis of variance models.

Results

Patients who had sustained meniscal tears showed a higher average rate of progression of cartilage loss (22%) than that seen in those who had intact menisci (14.9%) (P ≤ 0.018). Anterior cruciate ligament (ACL) tears had a borderline significant influence (P ≤ 0.06) on the progression of cartilage pathology. Lesions located in the central region of the medial compartment were more likely to progress to more advanced cartilage pathology (progression rate 28%; P ≤ 0.003) than lesions in the anterior (19%; P ≤ 0.564) and posterior (17%; P ≤ 0.957) regions or lesions located in the lateral compartment (average progression rate 15%; P ≤ 0.707). Lesions located in the anterior region of the lateral compartment showed less progression of cartilage degradation (6%; P ≤ 0.001). No specific grade of lesion identified at baseline had a predilection for more rapid cartilage loss (P ≤ 0.93).

Conclusion

MRI can detect interval cartilage loss in patients over a short period (<2 years). The presence of meniscal and ACL tears was associated with more rapid cartilage loss. Cartilage lesions located in the central region of the medial compartment showed more rapid progression of cartilage loss than cartilage lesions in the anterior and posterior portions of the medial compartment. The findings in this study suggest that patients entering clinical trials investigating antiarthritis regimens may need to be randomized based on location of the lesion.
Migration of CX3CR1‐positive T cells producing type 1 cytokines and cytotoxic molecules into the synovium of patients with rheumatoid arthritis
Authors: Nanki Toshihiro , Imai Toshio , Nagasaka Kenji , Urasaki Yasuyo , Nonomura Yoshinori , Taniguchi Ken , Hayashida Kenji , Hasegawa Jun , Yoshie Osamu , Miyasaka Nobuyuki
Published: November 2002

Objective

Rheumatoid arthritis (RA) is characterized by chronic inflammation of multiple joints. Large numbers of T cells, which produce type 1 cytokines, infiltrate into RA synovium. Chemokines and chemokine receptors are considered to contribute to the T cell infiltration. In this study, we examined the role of CX3CL1/fractalkine and its receptor CX3C chemokine receptor 1 (CX3CR1) in the T cell migration into RA synovium.

Methods

Using flow cytometry, immunohistochemistry, and reverse transcription–polymerase chain reaction, we analyzed CX3CR1 expression by peripheral blood and synovial T cells, and CX3CL1 expression in synovium from patients with RA. Cytokine and cytotoxic molecule expression by CX3CR1‐positive T cells was analyzed by flow cytometry.

Results

CX3CR1 expression by peripheral CD4+ and CD8+ T cells was up‐regulated in RA patients. The peripheral CD4+ and CD8+ T cells expressing CX3CR1 predominantly produced interferon‐γ and tumor necrosis factor α, and expressed cytotoxic molecules such as granzyme A and perforin. Furthermore, CX3CR1+,CD3+ T cells infiltrated into RA synovium. CX3CL1, the unique ligand of CX3CR1, was expressed by endothelial cells and synoviocytes in RA synovium, but not in osteoarthritis synovium.

Conclusion

Our findings suggest that the interactions of CX3CL1 and CX3CR1 might contribute to the accumulation of CX3CR1+ T cells expressing type 1 cytokines and possessing cytotoxic granules in RA synovium.
Artefacts and pitfalls in diffusion measurements by NMR
Authors: Sørland Geir Humborstad , Aksnes Dagfinn
Published: November 2002

When applying pulsed field gradient (PFG) NMR experiments to determine the molecular mobility characterized by the diffusion coefficient, it is crucial to have control over all experimental parameters that may affect the performance of the diffusion experiment. This could be diffusion measurement in the presence of magnetic field transients, internal magnetic field gradients, either constant or spatially varying, convection, mechanical vibrations, or in the presence of physical restrictions affecting the diffusion propagator. The effect of these parameters on the diffusion experiment is discussed and visualized. It is also outlined how to minimize their influence on the measured diffusivity that is extracted from the PFG‐NMR experiment. For an expanded and more general treatment we refer to the excellent reviews by Dr William S. Price (Concepts Magn. Reson. 1997; 9: 299; 1998; 10: 197) and the references therein. Copyright © 2002 John Wiley & Sons, Ltd.
Scope of droplet size measurements in food emulsions by pulsed field gradient NMR at low field
Authors: van Duynhoven J. P. M. , Goudappel G. J. W. , van Dalen G. , van Bruggen P. C. , Blonk J. C. G. , Eijkelenboom A. P. A. M.
Published: November 2002

Low‐field NMR instrumentation offers a user‐friendly and cost‐effective means for assessment of water and oil droplet size measurements in food emulsions. Examples are given of major food application areas, and these are supported with validation data in terms of precision and equivalence to other methods. The NMR method gives the same results as other techniques, such as microscopy, laser diffraction and electric sensing, but with similar or better precision. NMR distinguishes itself by a simple and non‐perturbing sample preparation procedure (in addition to the aforementioned advantages). For reliable results, the NMR parameters should be properly chosen and adjusted. A survey is given of experimental NMR parameters than can have an impact on the performance of water and oil droplet size determination. Copyright © 2002 John Wiley & Sons, Ltd.
NMR methods applied to anisotropic diffusion
Authors: Furó István , Dvinskikh Sergey V.
Published: November 2002

The methodology of NMR experiments intended to measure anisotropic diffusion is reviewed. Experiments of this kind preferably require oriented samples and/or orientation‐dependent spin coupling and/or magnetic field gradients in different directions. One strategy of diffusion experiments in anisotropic systems with broad NMR lines employs line narrowing techniques, thereby allowing for efficient gradient encoding/decoding. Depending on the nuclei, spin couplings and samples, the preferred methods vary from decoupling through echo techniques to magic angle sample orientation and spinning. Another avenue to efficient gradient encoding/decoding is through very strong magnetic field gradients. Either way, anisotropic diffusion reveals new structural features as illustrated by a few selected examples in liquid crystals and in biological tissues. Copyright © 2002 John Wiley & Sons, Ltd.
Performance of timber buildings under seismic load. Part 1: experimental studies
Authors: Lam Frank , Filiatrault Andre , Kawai Naohito , Nakajima Shiro , Yamaguchi Nobuyoshi
Published: November 2002

Several comprehensive research programmes were initiated recently in North America and Japan to improve our understanding of the seismic performance of timber buildings. A large database of experimental results and innovative modelling approaches were developed in these programmes. This paper is Part 1 of a two‐part series. It provides brief summaries of the performance of timber structures in the Northridge and Kobe earthquakes, and reports highlights from the state‐of‐art North American and Japanese experimental research activities. Part 2 of the paper will focus on the modelling aspect of this interesting and important problem.
The interactive dynamics of flow and
directional solidification in a Hele-Shaw cell
Part 1. Experimental investigation of parallel
shear flow
Authors: ZHANG M. , MAXWORTHY T.
Published: November 2002

It is recognized that flow in the melt can have a profound influence on the dynamics
of a solidifying interface and hence on the quality of the solidified material. To better
understand the effect of fluid flow on the interface morphological stability and on the
cellular and dendritic growth, directional solidification experiments were carried out
in a horizontally placed Hele-Shaw cell with and without externally imposed parallel
shear flow. The specimen material used was SCN–1.0 Wt% acetone. The experiment
shows that the transient parallel flow has a stabilizing effect on the planar interface by
damping the existing initial perturbations. The left–right symmetry of crystal cells was
broken by the parallel flow, with cells tilting toward the incoming flow direction. The
tilting angle increased with the velocity ratio. The secondary dendrites were found
to either not appear or appear much later on the downstream side of the crystal
cells. The wavelengths of the initial perturbations and of the cellular interface were
insensitive to the imposed flow.
Asymptotic modal approximation of nonlinear
resonant sloshing in a rectangular tank with
small fluid depth
Authors: FALTINSEN ODD M. , TIMOKHA ALEXANDER N.
Published: November 2002

The modal system describing nonlinear sloshing with inviscid flows in a rectangular
rigid tank is revised to match both shallow fluid and secondary (internal) resonance
asymptotics. The main goal is to examine nonlinear resonant waves for intermediate
depth/breadth ratio 0.1 [lsim ] h/l [lsim ] 0.24 forced by surge/pitch excitation with frequency
in the vicinity of the lowest natural frequency. The revised modal equations take
full account of nonlinearities up to fourth-order polynomial terms in generalized
coordinates and h/l and may be treated as a modal Boussinesq-type theory. The
system is truncated with a high number of modes and shows good agreement with
experimental data by Rognebakke (1998) for transient motions, where previous finite
depth modal theories failed. However, difficulties may occur when experiments show
significant energy dissipation associated with run-up at the walls and wave breaking.
After reviewing published results on damping rates for lower and higher modes,
the linear damping terms due to the linear laminar boundary layer near the tank's
surface and viscosity in the fluid bulk are incorporated. This improves the simulation
of transient motions. The steady-state response agrees well with experiments by
Chester & Bones (1968) for shallow water, and Abramson et al. (1974), Olsen &
Johnsen (1975) for intermediate fluid depths. When h/l [lsim ] 0.05, convergence problems
associated with increasing the dimension of the modal system are reported.
‘A Hundred Loves’, ‘A Thousand Lovers’: Portrayals of Sexuality in the Work of Thidaa Bunnaak
Authors: Harrison Rachel
Published: November 2002

As issues of gender and sexuality become an increasingly important focus in cultural studies, the work of the once popular woman writer of the 1950s and 1960s, Thidaa Bunnaak, draws Thai literature into the debate. This paper investigates the sexually explicit nature of Thidaa's fiction and the multiple meanings that erotic references might hold.
Morphological features of lipid droplet transition during porcine oocyte fertilisation and early embryonic development to blastocyst in vivo and in vitro
Authors: Kikuchi Kazuhiro , Ekwall Hans , Tienthai Paisan , Kawai Yasuhiro , Noguchi Junko , Kaneko Hiroyuki , Rodriguez-Martinez Heriberto
Published: November 2002

Lipid content in mammalian oocytes or embryos differs among species, with bovine and porcine oocytes and embryos showing large cytoplasmic droplets. These droplets are considered to play important roles in energy metabolism during oocyte maturation, fertilisation and early embryonic development, and also in the freezing ability of oocytes or embryos; however, their detailed distribution or function is not well understood. In the present study, changes in the distribution and morphology of porcine lipid droplets during in vivo and in vitro fertilisation, in contrast to parthenogenetic oocyte activation, as well as during their development to blastocyst stage, were evaluated by transmission electron microscopy (TEM). The analysis of semi-thin and ultra-thin sections by TEM showed conspicuous, large, electron-dense lipid droplets, sometimes associated with mitochondrial aggregates in the oocytes, irrespective of whether the oocytes had been matured in vivo or in vitro. Immediately after sperm penetration, the electron density of the lipid droplets was lost in both the in vivo and in vitro oocytes, the reduction being most evident in the oocytes developed in vitro. Density was restored in the pronculear oocytes, fully in the in vivo specimens but only partially in the in vitro ones. The number and size of the droplets seemed, however, to have decreased. At 2- to 4-cell and blastocyst stages, the features of the lipid droplets were almost the same as those of pronuclear oocytes, showing a homogeneous or saturated density in the in vivo embryos but a marbled or partially saturated appearance in the in vitro embryos. In vitro matured oocytes undergoing parthenogenesis had lipid droplets that resembled those of fertilised oocytes until the pronuclear stage. Overall, results indicate variations in both the morphology and amount of cytoplasmic lipid droplets during porcine oocyte maturation, fertilisation and early embryo development as well as differences between in vivo and in vitro development, suggesting both different energy status during preimplantation development in pigs and substantial differences between in vitro and in vivo development.
Down‐regulation of hepatic cytochrome P450 in chronic renal failure: role of uremic mediators
Authors: Guévin Carl , Michaud Josée , Naud Judith , Leblond Francois A , Pichette Vincent
Published: November 2002

Chronic renal failure (CRF) is associated with a decrease in liver cytochrome P450 (P450). The mechanism remains poorly understood. The present study aimed to investigate the effects of the serum of rats with CRF on liver P450.

Normal rat hepatocytes were incubated for 24 h with serum (concentration of 10%) from rats with CRF and from control animals in order to measure (1) total P450 level, (2) protein expression and mRNA levels of major P450 isoforms, and (3) some of their specific metabolic activities (N‐demethylation of erythromycin). Time‐course experiments (incubation time from 12 to 48 h) and dose‐response curves (concentration of serum ranging from 1 to 30%) have been conducted.

In normal hepatocytes incubated for 24 h with serum (concentration of 10%) from rats with CRF, total P450 level, protein expression and mRNA levels of several P450 isoforms (CYP2C6, 2C11, 3A1 and 3A2) were decreased by more than 35% (P<0.001) compared to serum from control animals. The protein expression as well as the mRNA levels of CYP2D were similar in hepatocytes incubated with serum from either control or CRF rats. The N‐demethylation of erythromycin was decreased by more than 35% (P<0.001) in hepatocytes incubated with serum from rats with CRF. The inhibitory effect of serum from rats with CRF tended to peak at 48 h of incubation and was maximum at a concentration of 20%.

In conclusion, uremic serum contains mediator(s) that down‐regulate the cytochrome P450 of normal hepatocytes secondary to reduced gene expression.

British Journal of Pharmacology (2002) 137, 1039–1046. doi:10.1038/sj.bjp.0704951
Control of photoperiod-regulated tuberization in potato by theArabidopsisflowering-time geneCONSTANS
Authors: Martínez-García Jaime F. , Virgós-Soler Ariadna , Prat Salomé
Published: November 2002

Photoperiod controls several responses throughout the plant life cycle, like germination, flowering, tuber formation, onset of bud dormancy, leaf abscission, and cambium activity. From these processes, flowering has been most extensively studied, especially inArabidopsis thaliana. Photoperiod sensing by the function of photoreceptors and the circadian clock appears to regulate flowering time viaArabidopsisCONSTANS (AtCO), a putative transcription factor that accelerates flowering in response to long days. The genetic factors controlling plant photoperiodic responses other than flowering are little known. However, interspecific grafting experiments demonstrated that the flower-inducing (florigen) and tuber- inducing (tuberigen) signals are functionally exchangeable. Here we show that constitutive overexpression in potato of theArabidopsisflowering-time geneAtCOimpairs tuberization under short-day inductive conditions;AtCOoverexpressing lines require prolonged exposure to short days to form tubers. Grafting experiments using these lines indicated that AtCO exerts its inhibitory effect on tuber formation by acting in the leaves. We propose that a conserved photoperiodic functional module may be involved in controlling distinct photoperiod-regulated evocation responses in different species. This module would involve the action of CONSTANS in the production of the elusive and long-distance acting florigen-tuberigen signal(s) in the leaves.
Coordination of the two heads of myosin during muscle contraction
Authors: Lidke Diane S. , Thomas David D.
Published: November 2002

We have used luminescence resonance energy transfer between regulatory light chains (RLC) to detect structural changes within the dimeric myosin molecule in contracting muscle fibers. Fully functional scallop muscle fibers were prepared such that each myosin molecule contained a terbium-labeled (luminescent donor) RLC on one head and a rhodamine-labeled (acceptor) RLC on the other. Time-resolved luminescence energy transfer between the two heads increased upon the transition from relaxation (ATP) to contraction (ATP plus Ca) and increased further in rigor (no ATP). Combined with experiments on mutant RLCs labeled specifically at other sites, these results support a model in which the force-generating weak-to-strong transition causes one myosin LC domain to tilt through a 30° angle toward the other, thus acting as a coordinated lever arm.
Glycoprotein gp110 of Epstein–Barr virus determines viral tropism and efficiency of infection
Authors: Neuhierl B. , Feederle R. , Hammerschmidt W. , Delecluse H. J.
Published: November 2002

The Epstein–Barr virus (EBV) genome has been detected in lymphomas and in tumors of epithelial or mesenchymal origin such as nasopharyngeal carcinoma or leiomyosarcoma. Thus, there is little doubt that EBV can infect cells of numerous lineagesin vivo, in contrast to itsin vitroinfectious spectrum, which appears restricted predominantly to B lymphocytes. We show here that the EBVBALF4gene product, the glycoprotein gp110, dramatically enhances the ability of EBV to infect human cells. gp110highviruses were up to 100 times more efficient than their gp110lowcounterparts in infecting lymphoid or epithelial cells. In addition, gp110highviruses infected the carcinoma cell line HeLa and the T cell lymphoma cell line Molt-4, both previously thought to be refractory to EBV infection. Analysis of several virus isolates showed that the amount ofBALF4present within mature virions markedly differed among these strains. In some strains, gp110 was found expressed during lytic replication not only at the nuclear but also at the cellular membrane. Heterologous expression of gp110 during the virus lytic phase neither altered virus concentration nor affected virus binding to cells. It appears that gp110 plays a crucial role after the virus has adhered to its cellular target. gp110 constitutes an important virulence factor that determines infection of non-B cells by EBV. Therefore, the use of gp110highviruses will help to determine the range of the target cells of EBV beyond B lymphocytes and provide a usefulin vitromodel to assess the oncogenic potential of EBV in these cells.
Amino acids regulate the intracellular trafficking of the general amino acid permease of
Saccharomyces
cerevisiae
Authors: Chen Esther J. , Kaiser Chris A.
Published: November 2002

The delivery to the plasma membrane of the general amino acid permease, Gap1p, of
Saccharomyces cerevisiae
is regulated by the quality of the nitrogen source in the growth medium. In an effort to define how different nitrogen sources control Gap1p sorting, we find that mutations in
GDH1
and
GLN1
that decrease the flux through the glutamate and glutamine synthesis pathways result in increased Gap1p sorting to the plasma membrane. Conversely, deletion of
MKS1
, which increases glutamate and glutamine synthesis, decreases Gap1p sorting to the plasma membrane. Glutamate and glutamine are not unusual in their ability to regulate Gap1p sorting, because the addition of all natural amino acids and many amino acid analogs to the growth medium results in increased Gap1p sorting to the vacuole. Importantly, amino acids have the capacity to signal Gap1p sorting to the vacuole regardless of whether they can be used as a source of nitrogen. Finally, we show that rapamycin does not affect Gap1p sorting, indicating that Gap1p sorting is not directly influenced by the
TOR
pathway. Together, these data show that amino acids are a signal for sorting Gap1p to the vacuole and imply that the nitrogen-regulated Gap1p sorting machinery responds to amino acid-like compounds rather than to the overall nutritional status associated with growth on a particular nitrogen source.
East Asian genotypes of
Helicobacter pylori
strains in Amerindians provide evidence for its ancient human carriage
Authors: Ghose Chandrabali , Perez-Perez Guillermo I. , Dominguez-Bello Maria-Gloria , Pride David T. , Bravi Claudio M. , Blaser Martin J.
Published: November 2002

Phylogenies of indigenous microbes have been used as surrogates for the origins of the hosts that carry them. Conversely, polymorphisms may be used to date the spread of a microbial species when information about their host populations is available. Therefore, we examined polymorphisms in
Helicobacter pylori
, which persistently colonize the human stomach, to test the hypothesis that they have been ancient inhabitants of humans. Three
H. pylori
loci that previously have been shown to have phylogeographic affinity have been analyzed for two populations with different ethnic origins from Venezuela. In a group of Amerindian subjects from Amazonia, East Asian
H. pylori
genotypes were present for each of the loci examined but were absent in a mestizo population from Caracas. These findings provide evidence that
H. pylori
has been present in humans at least since ancestors of Amerindians migrated from Asia more than 11,000 years ago.
Cofilin, But Not Profilin, Is Required for Myosin-I-Induced Actin Polymerization and the Endocytic Uptake in Yeast
Authors: Idrissi Fatima-Zahra , Wolf Bianka L. , Geli M. Isabel
Published: November 2002

Mutations in the budding yeast myosins-I (MYO3 andMYO5) cause defects in the actin cytoskeleton and in the endocytic uptake. Robust evidence also indicates that these proteins induce Arp2/3-dependent actin polymerization. Consistently, we have recently demonstrated, using fluorescence microscopy, that Myo5p is able to induce cytosol-dependent actin polymerization on the surface of Sepharose beads. Strikingly, we now observed that, at short incubation times, Myo5p induced the formation of actin foci that resembled the yeast cortical actin patches, a plasma membrane-associated structure that might be involved in the endocytic uptake. Analysis of the machinery required for the formation of the Myo5p-induced actin patches in vitro demonstrated that the Arp2/3 complex was necessary but not sufficient in the assay. In addition, we found that cofilin was directly involved in the process. Strikingly though, the cofilin requirement seemed to be independent of its ability to disassemble actin filaments and profilin, a protein that closely cooperates with cofilin to maintain a rapid actin filament turnover, was not needed in the assay. In agreement with these observations, we found that like the Arp2/3 complex and the myosins-I, cofilin was essential for the endocytic uptake in vivo, whereas profilin was dispensable.
Identification of a Novel Type of cGMP Phosphodiesterase That Is Defective in the ChemotacticstmFMutants
Authors: Meima Marcel E. , Biondi Ricardo M. , Schaap Pauline
Published: November 2002

StmF mutants are chemotactic mutants that are defective in a cGMP phosphodiesterase (PDE) activity. We identified a novel gene, PdeD, that harbors two cyclic nucleotide–binding domains and a metallo-β-lactamase homology domain. Similar to stmF mutants,pdeD-null mutants displayed extensively streaming aggregates, prolonged elevation of cGMP levels after chemotactic stimulation, and reduced cGMP-PDE activity. PdeDtranscripts were lacking in stmF mutant NP377, indicating that this mutant carries a PdeD lesion. Expression of a PdeD-YFP fusion protein in pdeD-null cells restored the normal cGMP response and showed that PdeD resides in the cytosol. When purified by immunoprecipitation, the PdeD-YFP fusion protein displayed cGMP-PDE activity, which was retained in a truncated construct that contained only the metallo-β-lactamase domain.
RESULTS FROM AMANDA
Authors:   For the AMANDA COLLABORATION., WIEBUSCH CHRISTOPHER , AHRENS J. , BAI X. , BARWICK S. W. , BECKA T. , BECKER K.-H. , BERTRAND D. , BERNADINI E. , BINON F. , BIRON A. , BÖSER S. , BOTNER O. , BOUCHTA A. , BOUHALI O. , BURGESS T. , CARIUS S. , CASTERMANS T. , CHEN A. , CHIRKIN D. , CONRAD J. , COOLEY J. , COWEN D. F. , DAVOUR A. , DE CLERCQ C. , DE YOUNG T. , DESIATI P. , DEWULF J.-P. , DOKSUS P. , EKSTRÖM P. , FESER T. , GAISSER T. K. , GAUG M. , GERHARDT L. , GOLDSCHMIDT A. , HALLGREN A. , HALZEN F. , HANSON K. , HARDTKE R. , HAUSCHILDT T. , HELLWIG M. , HERQUET P. , HILL G. C. , HULTH P. O. , HUNDERTMARK S. , JACOBSEN J. , KARLE A. , KOCI B. , KÖPKE L. , KOWALSKI M. , KUEHN K. , LAMOUREUX J. I. , LEICH H. , LEUTHOLD M. , LINDAHL P. , LIUBARSKY I. , MADSEN J. , MARCINIEWSKI P. , MATIS H. S. , MCPARLAND C. P. , MINAEVA Y. , MIOČINOVIĆ P. , MOCK P. C. , MORSE R. , NAHNHAUER R. , NEUNHÖFFER T. , NIESSEN P. , NYGREN D. R. , OGELMAN H. , OLBRECHTS PH. , PÉREZ DE LOS HEROS C. , POHL A. C. , PRICE P. B. , PRZYBYLSKI G. T. , RAWLINS K. , RESCONI E. , RHODE W. , RIBORDY M. , RICHTER S. , RODRÍGUEZ MARTINO J. , ROSS D. , SANDER H.-G. , SCHMIDT T. , SCHNEIDER D. , SCHWARZ R. , SILVESTRI A. , SOLARZ M. , SPICZAK G. M. , SPIERING C. , STEELE D. , STEFFEN P. , STOKSTAD R. G. , SUDHOFF P. , SULANKE K.-H. , TABOADA I. , THOLLANDER L. , TILAV S. , WALCK C. , WEINHEIMER C. , WIEBUSCH C. H. , WIEDEMANN C. , WISCHNEWSKI R. , WISSING H. , WOSCHNAGG K. , YODH G. , YOUNG S.
Published: November 2002

The Antarctic Muon and Neutrino Detector Array (AMANDA) is a high-energy neutrino telescope operating at the geographic South Pole. It is a lattice of photo-multiplier tubes buried deep in the polar ice. The primary goal of this detector is to discover astrophysical sources of high energy neutrinos. We describe the detector methods of operation and present results from the AMANDA-B10 prototype. We demonstrate the improved sensitivity of the current AMANDA-II detector. We conclude with an outlook to the envisioned sensitivity of the future IceCube detector.
QUANTUM INSTABILITY FOR MIXED STATES
Authors: NOWAKOWSKI MAREK
Published: November 2002

The analysis of the time evolution of unstable states which are linear superposition of other, observable, states can, in principle, be carried out in two distinct, non-equivalent ways. One of the methods, usually employed for the neutral kaon system, combines the mixing and instability into one single step which then results in unconventional properties of the mass-eigenstates. An alternative method is to remain within the framework of a Lagrangian formalism and to perform the mixing prior to the instability analysis. Staying close to the [Formula: see text] system, we compare both methods pointing out some of their shortcomings and advantages.
SECOND ORDER PERTURBATIONS OF FLAT DUST FLRW UNIVERSES WITH A COSMOLOGICAL CONSTANT
Authors: MENA FILIPE C. , TAVAKOL REZA , BRUNI MARCO
Published: November 2002

We summarize recent results concerning the evolution of second order perturbations in flat dust irrotational FLRW models with Λ ≠ 0. We show that asymptotically these perturbations tend to constants in time, in agreement with the cosmic no-hair conjecture. We solve numerically the second order scalar perturbation equation, and very briefly discuss its all time behaviour and some possible implications for the structure formation.
EXPONENTIAL GROWTH OF PARTICLE NUMBER FAR FROM THE PARAMETRIC RESONANCE
Authors: BANDEIRA de MELO FERNANDO da ROCHA VAZ , BRANDENBERGER ROBERT H. , MAIA ADOLFO
Published: November 2002

It is known that exponential particle creation can occur in situations which do not fall in the parametric resonance regime characterized by oscillations of the inflaton field about its minimum. Here we present a new analytical approach to exponential particle production which can occur when the inflaton is far from the minimum of its potential. Crucial for this effect is a term in the equation of motion which acts like a negative mass term, as occurs for tachyonic preheating and negative coupling particle production. Our techniques can be applied in models with a strong coupling between matter fields χ and the inflaton ϕ, or in some models in which the inflaton has a large amplitude of oscillation. On the other hand our analysis yields results which are quite model dependent. Although our analysis is general, in order to be clear we specialize, in this paper, to the model with interaction Lagrangian -g Mplϕχ2.
Allosteric Cascade of Spliceosome Activation
Authors: Brow David A.
Published: November 2002

▪ Abstract  Introns are removed from precursor messenger RNAs in the cell nucleus by a large ribonucleoprotein complex called the spliceosome. The spliceosome contains five subcomplexes called snRNPs, each with one RNA and several protein components. Interactions of the snRNPs with each other and the intron are highly dynamic, changing in an ordered progression throughout the splicing process. This allosteric cascade of interactions is programmed into the RNA and protein components of the spliceosome, and is driven by a family of DExD/H-box RNA-dependent ATPases. The dependence of cascade progression on multiple intron-recognition events likely serves to enforce the accuracy of splicing. Here, the progression of the allosteric cascade from the first recognition event to the first catalytic step of splicing is reviewed.
Genetics ofCryptococcus neoformans
Authors: Hull Christina M. , Heitman Joseph
Published: November 2002

▪ Abstract  Cryptococcus neoformans is a pathogenic fungus that primarily afflicts immunocompromised patients, infecting the central nervous system to cause meningoencephalitis that is uniformly fatal if untreated. C. neoformans is a basidiomycetous fungus with a defined sexual cycle that has been linked to differentiation and virulence. Recent advances in classical and molecular genetic approaches have allowed molecular descriptions of the pathways that control cell type and virulence. An ongoing genome sequencing project promises to reveal much about the evolution of this human fungal pathogen into three distinct varieties or species. C. neoformans shares features with both model ascomycetous yeasts (Saccharomyces cerevisiae, Schizosaccharomyces pombe) and basidiomycetous pathogens and mushrooms (Ustilago maydis, Coprinus cinereus, Schizophyllum commune), yet ongoing studies reveal unique features associated with virulence and the arrangement of the mating type locus. These advances have catapulted C. neoformans to center stage as a model of both fungal pathogenesis and the interesting approaches to life that the kingdom of fungi has adopted.
Lung Function and Cardiovascular Risk
Authors: Engström G. , Lind P. , Hedblad B. , Wollmer P. , Stavenow L. , Janzon L. , Lindgärde F.
Published: November 2002

Background—

The inverse relationship between pulmonary function and incidence of cardiovascular disease remains largely unexplained. This prospective study explored the hypothesis of a relationship with inflammation-sensitive plasma proteins.

Methods and Results—

Forced vital capacity (FVC) and plasma levels of fibrinogen, α
1
-antitrypsin, haptoglobin, ceruloplasmin, and orosomucoid were determined in 5064 healthy men aged 28 to 61 years. All-cause mortality, cardiovascular mortality, and incidence of myocardial infarction were monitored over a mean follow-up period of 18.4 years. Low FVC (fourth quartile) was associated with higher protein levels and with increased incidences of myocardial infarction and cardiovascular death. Adjustments for protein levels reduced the age-adjusted relative risks (RRs) for myocardial infarction (from 1.99, 95% CI 1.5 to 2.6, to 1.70, 95% CI 1.3 to 2.2) and cardiovascular death (from 2.71, 95% CI 1.9 to 3.9, to 2.28, 95% CI 1.6 to 3.3) among men with low FVC, corresponding to ≈25% of the excess risk. The risk factor–adjusted RRs were reduced from 1.45 (95% CI 1.1 to 1.9) to 1.38 (95% CI 1.1 to 1.8) and from 1.96 (95% CI 1.4 to 2.8) to 1.85 (95% CI 1.3 to 2.7) for myocardial infarction and cardiovascular death, respectively, corresponding to ≈10% to 15% of the excess risk. Among men with low FVC, the risk factor–adjusted RR for myocardial infarction was 2.5 (95% CI 1.7 to 3.6) for those with high protein levels (≥2 proteins in top quartile) and 1.7 (95% CI 1.1 to 2.4) for those with low protein levels (≤1 protein in top quartile; reference, top quartile of FVC and low protein levels).

Conclusions—

FVC is significantly and inversely associated with plasma levels of inflammation-sensitive plasma proteins. This relationship contributes to but cannot fully explain the increased cardiovascular risk among men with low FVC.
Mechanisms of effects of complement inhibition in murine collagen‐induced arthritis
Authors: Banda Nirmal K. , Kraus Damian , Vondracek Andrea , Huynh Long H. , Bendele Alison , Holers V. Michael , Arend William P.
Published: November 2002

Objective

To determine the mechanisms of amelioration of collagen‐induced arthritis (CIA) in DBA/1J mice by inhibition of complement activation.

Methods

Mice received 2 intradermal injections of bovine type II collagen (CII), on days 0 and 21. From day 21 (immediately after the second injection of CII) through day 35, mice received intraperitoneal injections of either phosphate buffered saline (PBS), a monoclonal mouse antibody to murine C5 (anti‐C5 antibody), or the C3 convertase inhibitor Crry‐Ig.

Results

On days 30 and 32, the clinical disease activity score was lower in mice treated with anti‐C5 antibody than in those treated with Crry‐Ig. Histopathologic evidence of joint damage was 75% lower in the mice treated with anti‐C5 antibody than in those treated with either PBS or Crry‐Ig. Spleen cells from mice receiving either form of complement inhibition exhibited decreased CII‐stimulated proliferation, whereas increased proliferative responses were exhibited by lymph node cells from mice treated with Crry‐Ig. Treatment with anti‐C5 antibody decreased production of IgG1 anticollagen antibody, while production of IgG2a antibody was inhibited by both complement inhibitory treatments. CII‐stimulated spleen cells from anti‐C5–treated mice produced lower levels of tumor necrosis factor α (TNFα) and interleukin‐10 (IL‐10) compared with those from mice treated with Crry‐Ig. Lower steady‐state messenger RNA (mRNA) levels for TNFα, interferon‐γ (IFNγ), IL‐18, and IL‐6 were observed in the joints of anti‐C5–treated mice, and for IFNγ and IL‐6 in mice receiving Crry‐Ig, all in comparison with PBS‐treated mice. However, mRNA levels for IL‐1β and TNFα were lower in the joints after treatment with anti‐C5 compared with Crry‐Ig.

Conclusion

These results indicate that inhibition of complement in CIA leads to decreased production of IgG2a antibody and suppressed CII‐induced spleen cell proliferation. The greater inhibitory effects on CIA of anti‐C5 antibody in comparison with Crry‐Ig may be attributable primarily to decreased levels of IL‐1β and TNFα mRNA in the joints.
Quantitative 1H NMR spectroscopic determination of the E/Z isomer ratio of the antidepressant drug fluvoxamine for use in pharmaceutical analysis
Authors: Deubner Ralph , Holzgrabe Ulrike
Published: November 2002

High‐resolution NMR spectroscopy is a powerful tool in the elucidation of a structure with respect to constitution, configuration and conformation. In recent years, NMR has been increasingly used in quantitative analysis. In this study, we show the ability of 1H NMR to determine the isomeric composition of the antidepressant drug fluvoxamine. The activity of fluvoxamine resides on the E‐isomer, and the current British Pharmacopoeia limits the content of the Z‐isomer to 0.5%. The NMR method described here is able to determine the content of the Z‐isomer down to the 0.2% level on a total amount of 15 mg of the substance. Copyright © 2002 John Wiley & Sons, Ltd.
Behaviour and analysis of masonry‐infilled frames
Authors: Shing P Benson , Mehrabi Armin B
Published: November 2002

Masonry infills are frequently used as interior partitions and exterior walls in buildings. They are usually treated as non‐structural elements, and their interaction with the bounding frame is often ignored in design. The performance of such structures during an earthquake has attracted major attention. Even though frame–infill interaction has sometimes led to undesired structural performance, recent studies have shown that a properly designed infilled frame can be superior to a bare frame in terms of stiffness, strength, and energy dissipation. A number of different analytical models have been developed to evaluate infilled structures. Nevertheless, most of the models proposed today have been validated with limited experimental data, and they have often yielded different performances when compared with recent test data. Limit analysis methods that can account for a variety of possible failure modes seem to be the most promising approach. However, these methods need to be further refined and validated in a systematic manner before they could be used in engineering practice. Sophisticated finite element models have also been developed to analyse infilled structures. While these models are general and widely applicable to different types of infilled frames, they should be used with caution because they could be easily misused and lead to unconservative results. This paper summarizes some of the recent findings and developments on the behaviour and modelling of infilled structures, and provides thoughts for future research.
The performance persistence of foreign closed‐end funds
Authors: Madura Jeff , Bers Martina K.
Published: November 2002

A sample of 26 foreign bond and 95 foreign equity closed‐end funds is used to determine whether foreign closed‐end funds exhibit performance persistence (PP). Persistence is measured using two different performance measures, net asset value (NAV) returns and market price (MP) returns. The results show that foreign closed‐end equity funds exhibit persistence of MP performance. These results are generally robust with respect to the holding period. In general, the PP results are mainly attributed to winning funds. A comparison of foreign to domestic closed‐end funds finds that foreign closed‐end equity funds exhibit less PP than domestic equity funds.
Phosphorylation of MAP kinase and p90rsk and its regulation during in vitro maturation of cumulus-enclosed rabbit oocytes
Authors: Yu Hai-Quan , Bou Shorgan , Chen Da-Yuen , Sun Qing-Yuan
Published: November 2002

Numerous studies have demonstrated that activation of the mitogen-activated protein (MAP) kinase is involved in the maturation of oocytes. In this study, the expression and phosphorylation of MAP kinase and p90rsk, one of the substrates of MAP kinase, during rabbit oocyte maturation were studied. The results showed that MAP kinase phosphorylation began to occur after germinal vesicle breakdown (GVBD) and the active form was maintained until metaphase II. p90rsk was also activated after GVBD following MAP kinase activation. Immunofluorescent analysis showed that p90rsk was enriched in the nuclear area after GVBD and was gradually localised to the spindle. When GVBD was inhibited by increased cAMP or decreased protein kinase C activity, the phosphorylation of both MAP kinase and p90rsk was blocked. Our data suggest that (1) MAP kinase/p90rsk activation is not necessary for GVBD, but plays an important role in the post-GVBD events including spindle assembly in rabbit oocytes; and (2) MAP kinase/p90rsk activation is down-regulated by cAMP and up-regulated by protein kinase C in cumulus-enclosed rabbit oocytes.