bluuebunny/crossref_metadata_2025_split huggingface dataset:
Testicular tumours in children: a single‐institutional experience
Authors: Oottamasathien Siam , Thomas John C. , Adams Mark C. , DeMarco Romano T. , Brock John W. , Pope John C. 
Published: February 2007

Authors from the USA present a retrospective review of children in their institution who were treated for testicular cancer. They found that most of the lesions were benign, the commonest being testicular. They also found several malignant and paratesticular lesions, and make recommendations as to the surgical approach.OBJECTIVETo report our experience of testicular and paratesticular tumours in children, as such tumours are rare, and historically yolk sac tumour has been described as the most common lesion in children, but recent reports suggest that benign testicular lesions might be more common.PATIENTS AND METHODSWe reviewed retrospectively the records of children treated for testicular tumours from 1998 to 2005. The patients’ age, clinical presentation, diagnostic procedures, treatment methods, histopathological findings, and outcome were recorded. Patients aged >144 months and those with non‐primary metastatic lesions were excluded.RESULTSIn all, 11 patients met our criteria, with a mean age of 37 months (range 9 days to 144 months). Pathological analysis revealed teratoma in four patients, yolk sac tumour in two, epidermoid cysts in two, extrarenal nephroblastomatosis in one, and paratesticular rhabdomyosarcomas in two. The most common clinical presentation was a painless testicular mass. Depending on the clinical presentation and pathology, scrotal ultrasonography, tumour markers (α‐fetoprotein and β‐human chorionic gonadotrophin), and/or staging computed tomography (CT) were obtained in eight patients. All patients had a radical orchidectomy. Three patients had elevated tumour markers that normalized after orchidectomy. CT revealed extensive mediastinal adenopathy in one patient with rhabdomyosarcoma. Chemotherapy was administered to both patients with rhabdomyosarcoma.CONCLUSIONAlthough there were few patients, most of the lesions were benign tumours, with the most common histological subtype being teratoma. As both malignant and paratesticular lesions occurred at a significant frequency, we would continue to advocate an initial radical inguinal approach at which time testis‐sparing could be considered if the preoperative evaluation was favourable, and frozen‐section analysis at the time of surgery confirms a benign lesion.
Scale‐related patterns in the spatial and environmental components of stream macroinvertebrate assemblage variation
Authors: Mykrä Heikki , Heino Jani , Muotka Timo 
Published: February 2007

ABSTRACTAim  We examined the relative contributions of spatial gradients and local environmental conditions to macroinvertebrate assemblages of boreal headwater streams at three hierarchical extents: bioregion, ecoregion and drainage system. We also aimed to identify the environmental variables most strongly related to assemblage structure at each study scale, and to assess how the importance of these variables is related to regional context and spatial structuring at different scales.Location  Northern Finland (62–68° N, 25–32° E).Methods  Variation in macroinvertebrate data was partitioned using partial canonical correspondence analysis into components explained by spatial variables (nine terms from the cubic trend surface regression), local environmental variables (15 variables) and spatially structured environmental variation.Results  The strength of the relationship between assemblage structure and local environmental variables increased with decreasing spatial extent, whereas assemblage variation related to spatial variables and spatially structured environmental variation showed the opposite pattern. At the largest extents, spatial variation was related to latitudinal gradients, whereas spatial autocorrelation among neighbouring streams was the likely mechanism creating spatial structure within drainage systems. Only stream size and water acidity were consistently important in explaining assemblage structure at all study scales, while the importance of other environmental variables was more context‐dependent.Main conclusions  The importance of local environmental factors in explaining macroinvertebrate assemblage structure increases with decreasing spatial extent. This scale‐related pattern is not caused solely by changes in study extent, however, but also by variable sample sizes at different regional extents. The importance of environmental gradients is context‐dependent and few factors are likely to be universally important correlates of macroinvertebrate assemblage structure. Finally, our results suggest that bioassessment should give due attention to spatial structuring of stream assemblages, because important assemblage gradients may not only be related to local factors but also to biogeographical constraints and neighbourhood dispersal processes.
The role of transitional areas as avian biodiversity centres
Authors: Kark Salit , Allnutt Thomas F. , Levin Noam , Manne Lisa L. , Williams Paul H. 
Published: February 2007

ABSTRACTAim  With the ever‐increasing threats to biodiversity, efforts are being directed towards identifying hotspots of special importance for conservation. In particular, there has been an effort to identify irreplaceable regions that are especially rich in rare species. Areas of transition between ecological systems in which multiple species coincide are expected, almost by definition, to be species‐rich. Here, we examine whether this is simply a result of an overlap between two communities in boundary regions, or whether boundary areas also hold concentrations of rare (e.g. range‐limited) species. We ask whether an analysis that includes areas of transition may be a useful contribution to the identification of biodiversity centres.Location and methods  To address these questions, we examined the relationship between passeriform richness and range size rarity of approximately 2300 bird species in 4889 1° New World grid cells, and the distance of the cells to boundaries between adjacent plant‐based ecoregions.Results  Areas nearer to boundary regions between ecoregions not only had more bird species, but also scored more highly in terms of species rarity. The range centres of the rarest 10% of species were distributed significantly closer to boundaries between ecoregions than were species in general. This pattern persisted for rarity when we divided the New World into three latitudinal belts and analysed each separately, and when we excluded the Andes. It also persisted when compared with randomly generated ecoregion polygons.Main conclusions  The findings of this work suggest that transitional environments harbour many rare species, in addition to high richness. Consequently areas of biotic transition should be highly valued as biodiversity centres and need to be included in future global conservation analyses and decisions.
One‐dimensional analyses of Rapoport's rule reviewed through meta‐analysis
Authors: Ruggiero Adriana , Werenkraut Victoria 
Published: February 2007

ABSTRACTAim To analyse quantitatively the extent to which several methodological, geographical and taxonomic variables affect the magnitude of the tendency for the latitudinal ranges of species to increase with latitude (the Rapoport effect).Location Global.Methods A meta‐analysis of 49 published studies was used to evaluate the effect of several methodological and biological moderator variables on the magnitude of the pattern.Results The method used to depict the latitudinal variation in range sizes is a strong moderator variable that accounts for differences in the magnitude of the pattern. In contrast, the extent of the study or the use of areal or linear estimations of range sizes does not affect the magnitude of the pattern. The effect of geography is more consistent than the effect of taxonomy in accounting for differences in the magnitude of the pattern. The Rapoport effect is indeed strong in Eurasia and North America. Weaker or non‐significant latitudinal trends are found at the global scale, and in Australia, South America and the New World. There are no significant differences in the magnitude of the pattern between different habitats, however, the overall pattern is weaker in oceans than in terrestrial regions of the world.Main conclusions The Rapoport effect is indeed strong in continental landmasses of the Northern Hemisphere. The magnitude of the effect is primarily affected by methodological and biogeographical factors. Ecological and spatial scale effects seem to be less important. We suggest that not all methodological approaches may be equally useful for analysing the pattern.
Functional analysis of rice NPR1‐like genes reveals that OsNPR1/NH1 is the rice orthologue conferring disease resistance with enhanced herbivore susceptibility†
Authors: Yuan Yuexing , Zhong Sihui , Li Qun , Zhu Zengrong , Lou Yonggen , Wang Linyou , Wang Jianjun , Wang Muyang , Li Qiaoli , Yang Donglei , He Zuhua 
Published: February 2007

SummaryThe key regulator of salicylic acid (SA)‐mediated resistance, NPR1, is functionally conserved in diverse plant species, including rice (Oryza sativa L.). Investigation in depth is needed to provide an understanding of NPR1‐mediated resistance and a practical strategy for the improvement of disease resistance in the model crop rice. The rice genome contains five NPR1‐like genes. In our study, three rice homologous genes, OsNPR1/NH1, OsNPR2/NH2 and OsNPR3, were found to be induced by rice bacterial blight Xanthomonas oryzae pv. oryzae and rice blast Magnaporthe grisea, and the defence molecules benzothiadiazole, methyl jasmonate and ethylene. We confirmed that OsNPR1 is the rice orthologue by complementing the Arabidopsis npr1 mutant. Over‐expression of OsNPR1 conferred disease resistance to bacterial blight, but also enhanced herbivore susceptibility in transgenic plants. The OsNPR1‐green fluorescent protein (GFP) fusion protein was localized in the cytoplasm and moved into the nucleus after redox change. Mutations in its conserved cysteine residues led to the constitutive localization of OsNPR1(2CA)‐GFP in the nucleus and also abolished herbivore hypersensitivity in transgenic rice. Different subcellular localizations of OsNPR1 antagonistically regulated SA‐ and jasmonic acid (JA)‐responsive genes, but not SA and JA levels, indicating that OsNPR1 might mediate antagonistic cross‐talk between the SA‐ and JA‐dependent pathways in rice. This study demonstrates that rice has evolved an SA‐mediated systemic acquired resistance similar to that in Arabidopsis, and also provides a practical approach for the improvement of disease resistance without the penalty of decreased herbivore resistance in rice.
Wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) multiple inositol polyphosphate phosphatases (MINPPs) are phytases expressed during grain filling and germination†
Authors: Dionisio Giuseppe , Holm Preben B. , Brinch‐Pedersen Henrik 
Published: February 2007

SummaryAt present, little is known about the phytases of plant seeds in spite of the fact that this group of enzymes is the primary determinant for the utilization of the major phosphate storage compound in seeds, phytic acid. We report the cloning and characterization of complementary DNAs (cDNAs) encoding one of the groups of enzymes with phytase activity, the multiple inositol phosphate phosphatases (MINPPs). Four wheat cDNAs (TaPhyIIa1, TaPhyIIa2, TaPhyIIb and TaPhyIIc) and three barley cDNAs (HvPhyIIa1, HvPhyIIa2 and HvPhyIIb) were isolated. The open reading frames ranged from 1548 to 1554 bp and the level of homology between the barley and wheat proteins ranged from 90.5% to 91.9%. All cDNAs contained an N‐terminal signal peptide encoding sequence, and a KDEL‐like sequence, KTEL, was present at the C‐terminal, indicating that the enzyme was targeted to and retained within the endoplasmic reticulum. Expression of TaPhyIIa2 and HvPhyIIb in Escherichia coli revealed that the MINPPs possessed a significant phytase activity with narrow substrate specificity for phytate. The pH and temperature optima for both enzymes were pH 4.5 and 65 °C, respectively, and the Km values for phytate were 246 and 334 µm for the wheat and barley recombinant enzymes, respectively. The enzymes were inhibited by several metal ions, in particular copper and zinc. The cDNAs showed significantly different temporal and tissue‐specific expression patterns during seed development and germination. With the exception of TaPhyIIb, the cDNAs were present during late seed development and germination. We conclude that MINPPs constitute a significant part of the endogenous phytase potential of the developing and germinating barley and wheat seeds.
Identification of a carboxylesterase expressed in protoplasts using fluorescence‐activated cell sorting
Authors: Cummins Ian , Steel Patrick G. , Edwards Robert 
Published: February 2007

SummaryA method was developed to identify plant carboxylesterases using a homologous expression system with the capacity for high‐throughput screening based on fluorescence‐activated cell sorting (FACS). Protoplasts of Arabidopsis thaliana were prepared and transfected with a mutated (Cys59Ser) Arabidopsis S‐formylglutathione hydrolase (atsfghm), which encoded a carboxylesterase highly active in the hydrolysis of the vital marker methylumbelliferyl acetate (MUA) to the fluorophore methylumbelliferone (MU). Unlike all other Arabidopsis carboxylesterases studied to date, AtSFGH and its more stable mutant variant AtSFGHm are insensitive to inhibition by organophosphate insecticides, such as paraoxon. By making use of the combined traits of a high carboxylesterase activity towards MUA and a lack of sensitivity to paraoxon, FACS was employed to selectively collect catalytically active atsfghm‐transformed protoplasts. A population of 400 000 protoplasts containing 8000 sfghm transformants was treated with paraoxon to inhibit endogenous esterase activity and then fed with MUA. Fluorescent cells expressing the AtSFGHm enzyme were then collected by FACS, and the presence of the respective transgene was confirmed by polymerase chain reaction, with 9.6% of the transformants recovered. We suggest that the use of FACS to identify other carboxylesterases which can be catalytically determined using plant cell fluorescence‐based assays could be a powerful method for the high‐throughput screening of new enzymes, especially those which do not express well in microbial hosts.
International Patterns of Union Membership
Authors: Blanchflower David G. 
Published: February 2007

AbstractThis paper examines changes in unionization that have occurred over the last decade or so using individual level micro data on many countries, with particular emphasis on the United Kingdom, the United States and Canada. I document an empirical regularity not hitherto identified, namely the probability of being unionized follows an inverted U‐shaped pattern in age, maximizing in the mid‐ to late 40s in 34 of the 38 countries I study. I consider the question of why union membership seems to follow a similar inverted U‐shape pattern in age across countries with such diverse industrial relations systems. I find evidence that this arises in part because of cohort effects, but even when cohort effects are removed a U‐shape remains.
Vertical Disintegration and the Disorganization of German Industrial Relations1
Authors: Doellgast Virginia , Greer Ian 
Published: February 2007

AbstractDrawing on case studies from the telecommunications and auto industries, the authors argue that the vertical disintegration of major German employers is contributing to the disorganization of Germany’s dual system of in‐plant and sectoral negotiations. Subcontractors, subsidiaries and temporary agencies often have no collective bargaining institutions or are covered by different firm‐level and sectoral agreements. As core employers move jobs to these firms, they introduce new organizational boundaries across the production chain and disrupt traditional bargaining structures. Worker representatives are developing new campaign approaches and using residual power at large firms to establish representation in new firms and sectors, but these have not been successful at rebuilding co‐ordinated bargaining.
Polymorphic microsatellite markers for Mexican salamanders of the genus Ambystoma
Authors: PARRA‐OLEA G. , RECUERO E. , ZAMUDIO K. R. 
Published: February 2007

AbstractWe screened a partial genomic library enriched for microsatellites and characterized nine loci for the Mexican species of Ambystoma for studies of population structure. We tested marker variability in two metamorphic (A. granulosum, A. altamirani) and two paedomorphic (A. andersoni, A. mexicanum) species of the A. tigrinum complex. Our microsatellites were developed from pooled genomic DNA from three species, and may work on all species in the A. tigrinum complex in Mexico. These markers will be important for studies of conservation genetics in this radiation.
A simple procedure for joint estimation of the long‐term rates of sexuality and mutation in predominantly clonal populations, for use with dominant molecular markers
Authors: THOMPSON STACEY LEE 
Published: February 2007

AbstractIn highly clonal populations, mutation can contribute to the rate of apparent sexuality. To remove this bias, a method is presented that jointly estimates the rates of sexuality (Ns) and mutation (Nµ) for populations, based upon levels of single‐locus vs. multilocus clonal identity. This effectively haploid model assumes equilibrium, and can be used with dominant molecular data and in conjunction with organisms of various ploidies. Simulations indicate that while equilibrium can take thousands of generations to attain, and afterwards have a large evolutionary variance, the method gives approximate estimates of Ns.
Isolation and characterization of polymorphic microsatellite loci from an EST library of turbot (Scophthalmus maximus) and cross‐species amplification
Authors: CHEN S. L. , MA H. Y. , JIANG Y. , LIAO X. L. , MENG L. 
Published: February 2007

AbstractIn the present study, we report 12 polymorphic microsatellite loci developed from a cDNA library from the turbot, Scophthalmus maximus. Observed and expected heterozygosities varied from 0.20 to 1.00 and from 0.18 to 0.78, respectively. No significant linkage disequilibrium between pairs of loci was found, but two loci significantly deviated from Hardy–Weinberg equilibrium after Bonferroni correction. Cross‐species amplifications of these microsatellites in five additional fish species revealed between five and 11 positive amplifications and between zero and four polymorphic loci per species.
Practical approach for estimation of subcutaneous and visceral adipose tissue
Authors: Kullberg Joel , Von Below Catrin , Lönn Lars , Lind Lars , Ahlström Håkan , Johansson Lars 
Published: February 2007

SummaryObjectives:  The first objective was to investigate the correlations between anthropometrical measurements and visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in two cohorts differing in age using magnetic resonance imaging (MRI) as reference. A second objective was to investigate the potential usage of abdominal diameters in practical estimation of adipose tissue compartments using these cohorts.Methods:  Measurements of body mass index, waist circumference, sagittal abdominal diameter (sagittal AD) and transverse abdominal diameter (transverse AD) were obtained from 336 volunteers of age 14–70 years. Manual measurements of VAT and SAT from single slice MRI at the L4‐L5 level were used as reference. The abdominal diameters were measured from the MR images. Linear correlations between the anthropometrical measurements and the reference were studied.Results:  Sagittal AD showed the strongest correlation to VAT (r ≥ 0·780, P<0·0001) and transverse AD was found to give information about the amount of SAT (r ≥ 0·866, P<0·0001). The ellipse spanned by the sagittal AD and the transverse AD was strongly correlated to the total amount of adipose tissue (r ≥ 0·962, P<0·0001).Conclusion:  Strong correlations were found between sagittal and transverse abdominal diameters, assessed using MRI, and VAT and SAT, respectively. These results suggest the use of abdominal diameters in practical estimations of VAT and SAT depots.
Yo Jyo Hen Shi Ko, a novel Chinese herbal, prevents nonalcoholic steatohepatitis in ob/ob mice fed a high fat or methionine–choline‐deficient diet
Authors: Lima Vicência Mara Rodrigues de , Oliveira Claudia Pinto Marques Souza de , Sawada Letícia Yumi , Barbeiro Hermes Vieira , Mello Evandro Sobroza de , Soriano Francisco Garcia , Alves Venâncio Avancini Ferreira , Caldwell Stephen H. , Carrilho Flair José 
Published: February 2007

AbstractBackground: Oxidative stress plays a role in the pathogenesis of nonalcoholic steatohepatitis (NASH). Yo Jyo Hen Shi Ko (YHK) is a complex compound purported to reduce reactive oxygen species (ROS) by blocking the propagation of radical‐induced reactions. The aim of this study was to evaluate the role of the effect of YHK in experimental NASH.Methods: NASH was induced in male ob/ob mice by a high‐fat (HF) diet or methionine/choline‐deficient (MCD) diet for 4 weeks. YHK‐treated animals received YHK solution orally (20 mg/kg/day) in both experimental diets (n=6; each group) while control animals received only vehicle.Results: The MCD and HF groups developed moderate diffuse macrosteatosis, hepatocellular ballooning, and a diffuse inflammatory infiltrate. With the addition of YHK, there was a marked reduction in macrosteatosis in both groups. This was associated with decreased lipoperoxide and reduced glutathione–GSH concentrations as well as reduced serum aminotransferases and improved histological markers of inflammation. These changes were also associated with weight loss in the MCD+YHK group and diminished weight gain in the HF+YHK group.Conclusion: YHK therapy blunts the development of macrosteatosis in these models of NASH and significantly reduces markers of oxidative stress. YHK also diminishes weight gain in this obesity prone model. Our findings warrant further study on the mechanisms involved with these effects.
Adenovirus‐mediated hepatic syndecan‐1 overexpression induces hepatocyte proliferation and hyperlipidaemia in mice
Authors: Cortés Víctor , Amigo Ludwig , Donoso Katherine , Valencia Ilse , Quiñones Verónica , Zanlungo Silvana , Brandan Enrique , Rigotti Attilio 
Published: February 2007

AbstractBackground: Heparan sulfate proteoglycans (HSPGs) have been involved in the regulation of cell growth, apoptosis and lipid metabolism in vitro; however, their functional role in vivo remains unknown.Aim: Here, we describe hepatic tissue and lipid metabolism changes after liver overexpression of syndecan‐1 (SDC‐1), the main hepatic HSPG, in mice induced by adenoviral gene transfer.Results: SDC‐1 overexpression was associated with marked hepatocyte proliferation, cell‐isolated apoptosis and increased plasma alanine aminotransferase (ALT) levels. Additionally, SDC‐1 liver overexpression significantly raised plasma cholesterol and triglyceride concentrations due to an increase in all lipoprotein particles, including the appearance of large and apolipoprotein (apo) E‐enriched high‐density lipoprotein (HDL) particles. Hepatic very low‐density lipoprotein (VLDL) production was not affected by SDC‐1 overexpression, suggesting a delayed plasma clearance of apo B lipoproteins as the underlying hyperlipidaemic mechanism. These pleotropic effects were qualitatively equivalent, even though less intense, in mice overexpressing a cytoplasmic C‐terminal domain‐deleted SDC‐1.Conclusions: This is the first report in vivo of the biological effects induced by a specific HSPG in the liver, with potential implications in both regenerative biology and molecular lipidology.