bluuebunny/crossref_metadata_2025_split huggingface dataset:
Upregulation of Adipose 11‐β‐Hydroxysteroid Dehydrogenase Type 1 Expression in Ovariectomized Rats Is due to Obesity Rather Than Lack of Estrogen
Authors: Paulsen Søren K. , Nielsen Maria P. , Richelsen Bjørn , Bruun Jens M. , Flyvbjerg Allan , Pedersen Steen B. 
Published: March 2008

Objective: Increased tissue activity of cortisol induced by the activation of inert cortisone to active cortisol through 11‐β‐hydroxysteroid dehydrogenase type 1 (11β‐HSD1) may play a role in the metabolic syndrome. We recently found that 11β‐HSD1 in subcutaneous adipose tissue (AT) was lower in lean women compared with lean men. Estrogen suppresses hepatic and renal 11β‐HSD1 in rats; hence we investigated the in vitro effect of estrogen on human and rat AT, and the in vivo effects on rat AT 11β‐HSD1 expression.Methods and Procedures: Wistar rats were divided into four groups of eight animals. One group was sham‐operated (controls) and others were ovariectomized (OVX). One OVX group was left untreated (OVX−E), another (OVX+E) received estrogen treatment, and one received a hypo‐caloric diet (OVX−E+D), matching the weight gain of the control group. AT from women undergoing liposuction or surgery and from killed male and female rats were incubated with estrogen alone or in the presence of IL‐1β. Gene expressions were determined by real‐time reverse transcriptase PCR.Results: Ovariectomy resulted in a 280% increase in adipose 11β‐HSD1 expression P < 0.05). 11β‐HSD1 expression in the (OVX+E)‐group was significantly reduced compared with the nonsubstituted group (P < 0.05). 11β‐HSD1 expression in the (OVX−E+D)‐group was reduced significantly (P < 0.05) when compared with the level of the estrogen‐substituted group. No significant differences between the control group, the (OVX+E)‐group, and the (OVX−E+D)–group were found. In the in vitro studies, no direct effect of estrogen on adipose 11β‐HSD1 was found.Discussion: The upregulation of 11β‐HSD1 in ovariectomized rats was most likely due to changes in body composition rather than lack of estrogen.
Negative Peer Perceptions of Obese Children in the Classroom Environment
Authors: Zeller Meg H. , Reiter‐Purtill Jennifer , Ramey Christina 
Published: March 2008

Objective: It is asserted that the more immediate and observable consequences of pediatric obesity are psychosocial in nature. This study examines the peer relations of clinically referred obese youth compared to demographically comparable nonoverweight peers within the classroom environment.Methods and Procedures: Peer‐, teacher‐, and self‐reports of behavioral reputation (Revised Class Play (RCP)), and peer reports of social acceptance, nonsocial attributes (attractiveness, athleticism, academic competence), and health interference (school absence, illness, fatigue) were obtained regarding 90 obese youth (BMI > 95th percentile; 8–16 years, 57% girls, 50% African American) and 76 nonoverweight demographically similar comparison classmates.Results: Relative to comparison peers, obese children were nominated significantly less often as a best friend and rated lower in peer acceptance, although the two groups did not differ in the number of reciprocated friendships. Obese youth were described by peer, teacher, and self‐report as more socially withdrawn and by peers as displaying less leadership and greater aggressive‐disruptive behavior. Peers also described obese youth as less physically attractive, less athletic, more sick, tired, and absent from school. Being seen as less attractive and less athletic by peers helped to explain differences in obese and nonoverweight youth's levels of peer acceptance.Discussion: Clinically referred obese youth are characterized by peer relations that differ from those of nonoverweight youth. The peer environment provides a rich context to understand the social consequences of pediatric obesity as well as factors that could be targeted in intervention to promote more positive health and psychosocial outcomes.
Obesity and C‐reactive Protein Levels Among White, Black, and Hispanic US Adults
Authors: Wee Christina C. , Mukamal Kenneth J. , Huang Annong , Davis Roger B. , McCarthy Ellen P. , Mittleman Murray A. 
Published: March 2008

Objective: Studies suggest that obesity's adverse impact on cardiovascular mortality may be reduced in African Americans relative to white Americans. We examined whether obesity's association with novel cardiovascular risk factors such as C‐reactive protein (CRP) also varies by race and ethnicity.Methods and Procedures: We analyzed data from 10,492 white, African‐American, and Hispanic‐American participants of the 1999–2004 National Health and Nutrition Examination Survey, who were aged 20 years and older, with a BMI ≥18.5 kg/m2 and CRP ≤10 mg/l. We fit sex‐specific multivariable models of the association of BMI or waist circumference with log CRP levels and tested for interactions of BMI or waist circumference with race/ethnicity.Results: Higher BMI was significantly associated with higher CRP in all racial/ethnic groups for both men and women (P > 0.05 for BMI–race/ethnicity interaction) before and after adjustment for age, education, and health behaviors. Larger waist circumference was also associated with higher CRP levels in all racial/ethnic groups before and after adjustment; among women, the relationship was strongest for Mexican Hispanics (P < 0.01 for waist circumference–race/ethnicity interaction). Results were similar after additional adjustment for medications that might affect CRP levels.Discussion: The association between obesity and CRP is at least as strong in African Americans and Hispanic Americans as in white Americans. Racial differences in the relationship between obesity and cardiovascular mortality are unlikely to be due to racial differences in obesity's impact on CRP.
The effects of conformational heterogeneity on the binding of the Notch intracellular domain to effector proteins: a case of biologically tuned disorder
Authors: Bertagna Angela , Toptygin Dima , Brand Ludwig , Barrick Doug 
Published: March 2008

Cell-fate decisions in metazoans are frequently guided by the Notch signalling pathway. Notch signalling is orchestrated by a type-1 transmembrane protein, which, upon interacting with extracellular ligands, is proteolytically cleaved to liberate a large intracellular domain [NICD (Notch intracellular domain)]. NICD enters the nucleus where it binds the transcription factor CSL (CBF1/suppressor of Hairless/Lag-1) and activates transcription of Notch-responsive genes. In the present paper, the interaction between the Drosophila NICD and CSL will be examined. This interaction involves two separate binding regions on NICD: the N-terminal tip of NICD {the RAM [RBP-Jκ (recombination signal-binding protein 1 for Jκ)-associated molecule] region} and an ankyrin domain ∼100 residues away. CD studies show that the RAM region of NICD lacks α-helical and β-sheet secondary structure, and also lacks rigid tertiary structure. Fluorescence studies show that the tryptophan residues in RAM are highly solvated and are quenched by solvent. To assess the impact of this apparent disorder on the bivalent binding of NICD to CSL, we modelled the region between the RAM and ANK (ankyrin repeat)-binding regions using polymer statistics. A WLC (wormlike chain) model shows that the most probable sequence separation between the two binding regions is ∼50 Å (1 Å=0.1 nm), matching the separation between these two sites in the complex. The WLC model predicts a substantial enhancement of ANK occupancy via effective concentration, and suggests that the linker length between the two binding regions is optimal for bivalent interaction.
Receptor protein tyrosine phosphatase μ: measuring where to stick
Authors: Aricescu A. Radu , Siebold Christian , Jones E. Yvonne 
Published: March 2008

We review here recent results on the structure and function of a receptor protein tyrosine phosphatase, RPTPμ. In addition to their intercellular catalytic domains which bear the phosphatase activity, the RPTPs are cell-surface-receptor-type molecules and in many cases have large extracellular regions. What role can these extracellular regions play in function? For RPTPμ, the extracellular region is known to mediate homophilic adhesion. Sequence analysis indicates that it comprises six domains: an N-terminal MAM (meprin/A5/μ), one immunoglobulin-like domain and four fibronectin type III (FN) repeats. We have determined the crystal structure of the entire extracellular region for RPTPμ in the form of a functional adhesion dimer. The physical characteristics and dimensions of the adhesion dimer suggest a mechanism by which the location of this phosphatase can be influenced by cell–cell spacings.
Differences in the expression of the ASIP gene are involved in the recessive black coat colour pattern in sheep: evidence from the rare Xalda sheep breed
Authors: Royo L. J. , Álvarez I. , Arranz J. J. , Fernández I. , Rodríguez A. , Pérez‐Pardal L. , Goyache F. 
Published: March 2008

SummaryHere we have tested the hypothesis of association between different levels of agouti signalling peptide (ASIP) mRNA and the recessive black coat colour in the rare Xalda breed of sheep. To deal with this task, we first tested the possible action of both the dominant black extension allele (ED) and a 5‐bp deletion (X99692:c.100_104del; Adel) in the ovine ASIP coding sequence on the black coat colour pattern in 188 Xalda individuals. The ED allele was not present in the sample and only 11 individuals were homozygous for the AdelASIP allele. All Xalda individuals carrying the Adel/Adel genotype were phenotypically black. However, most black‐coated individuals (109 out of 120) were not homozygous for the 5‐bp deletion, thus rejecting the Adel/Adel genotype as the sole cause of recessive black coat colour in sheep. Differences in expression of ASIP mRNA were assessed via RT‐PCR in 14 black‐coated and 10 white‐coated Xalda individuals showing different ASIP genotypes (Awt/Awt, Awt/Adel and Adel/Adel). Levels of expression in black animals were significantly (P < 0.0001) lower than those assessed for white‐coated individuals. However, the ASIP genotype did not influence the ASIP mRNA level of expression. The consistency of these findings with those recently reported in humans is discussed, and the need to isolate the promoter region of ovine ASIP to obtain further evidence for a role of ASIP in recessive black ovine pigmentation is pointed out.
An experimental study of crust development on chalk downland soils and their impact on runoff and erosion
Authors: Robinson D. A. , Woodun J. K. 
Published: March 2008

SummaryThe sealing of soil surfaces by rainfall, the development of soil crusts and their impact on runoff and erosion was investigated in the laboratory by means of simulated rainfall. The soils investigated were stone‐free samples of chalk soils from southeast England, and soils with a 25% cover of stones. Vertical change to the surface and immediate subsurface of the soils was assessed through the examination of thin sections scanned into a computer and analysed with image processing software. Changes in roughness and microtopography of the soil surface were measured by use of a laser micromapper. Crusting occurred both in the presence and absence of stones and was inversely related to the organic matter content and aggregate stability of the soils. Crusting of stone‐free soils was accompanied by a reduction in roughness of the soil surface, but roughness of the stone‐covered surfaces increased as crusting developed. Increases in the particle density of the crust were related to silt content. Organic‐rich soil from under permanent grass and from a soil recently brought into arable cultivation crusted less than soils used for arable cultivation for longer periods with lower organic content. The inwashing of silt into the pores of the soil during crusting reduces infiltration, and increases runoff and erosion. In the presence of a 25% cover of surface stones, the reduction in infiltration was 25% less than for stone‐free soils and erosion ∼50% less.
Effect of boundary layer on drying mechanisms of beach and desert sand
Authors: Almubarak A. A. , Al‐Saeedi J. N. , Shoukry M. 
Published: March 2008

SummaryA boundary layer developed over a flat‐plate surface plays a great role in the mechanisms of convective drying. Beds of desert sand, beach sand and glass beads were subjected to forced convective drying in a scaled‐up wind tunnel. The resulting temperature distribution profiles demonstrated clearly the stages of the drying process. A mathematical model is proposed to predict the temperature profile along the surface at various intervals. Good agreement was obtained between predicted and measured temperature profiles throughout the bed. The results showed a significant difference in the temperature along the bed. Surface temperature decreased gradually with increase in the distance from the leading edge. In a bed of 1 m long, the difference in the surface temperature was 11°C for the case of desert sand, and was 8°C for the case of beach sand. The results also revealed that the part of the bed closest to the leading edge dried faster. The reported results give a clear picture for the great role of the boundary layer in the drying mechanisms of the beach and desert sand.
Wetting of agricultural soil measured by a simplified capillary rise technique
Authors: Matthews G. P. , Watts C. W. , Powlson D. S. , Price J. C. , Whalley W. R. 
Published: March 2008

SummaryWe describe the use of a capillary rise method to measure the wettability of 10 samples of agricultural soil from Rothamsted long‐term experimental sites. The samples have very similar clay contents, but organic carbon (C) contents range from 11.5 to 31.2 g kg−1. Their wetting rates were interpreted by an improved method of data analysis, consistent with the Washburn equation, and showed an increase in the effective contact angle between the water meniscus and the soil with increasing C content. This corresponds to a decrease in wettability with increasing C content, and accords with other results reported in the literature. By contrast with water, we found that capillary rise for n‐hexane into soil did not depend on the soil’s bulk density or C content. A priori calculations of the expected wetting rates from fluid properties and an effective hydraulic radius estimated by other methods gave magnitudes and trends that agreed with our experimental data. The results show that estimates of effective hydraulic radius can provide a useful approximation for characterizing soil wetting, but that further modelling should be carried out.
Modelling hepatitis C virus kinetics during treatment with pegylated interferon α‐2b: errors in the estimation of viral kinetic parameters
Authors: Shudo E. , Ribeiro R. M. , Perelson A. S. 
Published: March 2008

Summary.  Neumann et al. [1] developed a widely used model for the analysis of hepatitis C virus (HCV) dynamics after the initiation of interferon therapy that assumes the effectiveness of therapy in blocking virion production, ε, is constant. However, with pegylated interferon α‐2b (PEG‐IFN) given weekly, there are significant changes in drug concentration between doses, leading to changes in drug effectiveness and viral rebounds. To investigate the appropriateness of the constant effectiveness (CE) model [1] for studies involving PEG‐IFN, we simulated PEG‐IFN treatment, using 294 sets of pharmacokinetic/pharmacodynamic (PK/PD) parameters that span observed ranges and fit the simulated data to the CE model. For most combinations of PK/PD parameters, the fits resulted in an infected cell loss rate, δ, that underestimates the true value used in the simulations and yielded over‐estimates of the average effectiveness of PEG‐IFN. In the setting of PEG‐IFN therapy, the use of the CE model of HCV kinetics has to be reevaluated and the validity of its use depends on the amount of HCV RNA rebound observed between doses.
The massive star binary fraction in young open clusters – I. NGC 6231 revisited
Authors: Sana H. , Gosset E. , Nazé Y. , Rauw G. , Linder N. 
Published: March 2008

Abstract
We present the results of a long-term high-resolution spectroscopy campaign on the O-type stars in NGC 6231. We revise the spectral classification and multiplicity of these objects and we constrain the fundamental properties of the O-star population. Almost three quarters of the O-type stars in the cluster are members of a binary system. The minimum binary fraction is 0.63, with half the O-type binaries having an orbital period of the order of a few days. The eccentricities of all the short-period binaries are revised downward, and henceforth match a normal period–eccentricity distribution. The mass ratio distribution shows a large preference for O + OB binaries, ruling out the possibility that, in NGC 6231, the companion of an O-type star is randomly drawn from a standard initial mass function. Obtained from a complete and homogeneous population of O-type stars, our conclusions provide interesting observational constraints to be confronted with the formation and early evolution theories of O-stars.
The study of the extended haplotypes of rare HLA‐B*2730 allele using microsatellite loci
Authors: Grubić Z. , Štingl K. , Kerhin‐Brkljačić V. , Žunec R. 
Published: March 2008

AbstractThe aim of the present study was to compare haplotypes of the most frequent B*27 alleles among Croatians (B*2702 and *2705) and the rare B*2730 allele. For this purpose, 37 families with members carrying human leukocyte antigen (HLA)‐B27 were selected. All individuals were analysed for eight microsatellites (Msats): D6S2927, short tandem repeat – MHC class I‐related gene (STR_MICA), D6S2793, D6S2811, tumor necrosis factor a (TNFa), tumor necrosis factor d (TNFd), D6S273 and D6S1014, while individuals carrying the HLA‐B27 specificity were subtyped. Of 39 analysed haplotypes, 20 individuals had B*2702, 15 subjects were positive for the B*2705 allele, the B*2730 allele was found in three haplotypes from different families, while one individual carried the B*2703 allele. HLA‐A3 and ‐DRB1*16 were shared by all three B*2730 haplotypes. The DRB1*16 allele was also observed in the majority of B*2702 haplotypes (76.5%), while HLA‐A3 was, after HLA‐A2, the second most frequent HLA‐A specificity in B*2702 haplotypes. No such correlation was found for the B*2705 haplotypes. Msat analysis showed that B*2730 haplotypes also share the same allele at all tested Msats. The D6S2927, D6S2793, MICA and TNFd Msats were not useful in distinguishing B*2702 and B*2705 alleles because D6S2927‐213bp, STR_MICA‐179bp, D6S2793‐206bp, D6S2811‐83bp and TNFd‐130bp were detected in almost all cases. Conversely, for the TNFa, D6S273 and D6S1014 loci, haplotypes carrying B*2702 and B*2730 shared a single Msat allele in the majority of cases (TNFa‐113bp, D6S1014‐134bp and D6S273‐134bp), which was not observed for B*2705 haplotypes. In conclusion, the similarity between B*2702 and B*2730 DNA sequences as well as their sharing of the same haplotypic combinations corroborates the proposed mechanism of B*2730 evolution from B*2702 by interallelic recombination.
Molecular phylogeny and divergence dates for Australasian elapids and sea snakes (hydrophiinae): evidence from seven genes for rapid evolutionary radiations
Authors: SANDERS K. L. , LEE M. S. Y. , LEYS R. , FOSTER R. , SCOTT KEOGH J. 
Published: March 2008

AbstractOne of the most prolific radiations of venomous snakes, the Australo‐Melanesian Hydrophiinae includes ∼100 species of Australasian terrestrial elapids plus all ∼60 species of viviparous sea snakes. Here, we estimate hydrophiine relationships based on a large data set comprising 5800 bp drawn from seven genes (mitochondrial: ND4, cytb, 12S, 16S; nuclear: rag1, cmos, myh). These data were analysed using parsimony, likelihood and Bayesian methods to better resolve hydrophiine phylogeny and provide a timescale for the terrestrial and marine radiations. Among oviparous forms,Cacophis, FurinaandDemansiaare basal to other Australian elapids (core oxyuranines). The MelanesianToxicocalamusandAspidomorphusgroup withDemansia, indicating multiple dispersal events between New Guinea and Australia.OxyuranusandPseudonajaform a robust clade. The small burrowing taxa form two separate clades, one consisting ofVermicellaandNeelaps calanotus, and the other includingSimoselaps,BrachyurophisandNeelaps bimaculatus. The viviparous terrestrial elapids form three separate groups:Acanthophis, theRhinoplocephalusgroup and theNotechis–Hemiaspisgroup. True sea snakes (Hydrophiini) are robustly united with theNotechis–Hemiaspisgroup. Many of the retrieved groupings are consistent with previous molecular and morphological analyses, but the polyphyly of the viviparous and burrowing groups, and ofNeelaps, are novel results. Bayesian relaxed clock analyses indicate very recent divergences: the ∼160 species of the core Australian radiation (including sea snakes) arose within the last 10 Myr, with most inter‐generic splits dating to between 10 and 6 Ma. TheHydrophissea snake lineage is an exceptionally rapid radiation, with > 40 species evolving within the last 5 Myr.
The effects of warming methods on temperature, cardiac function and cytokines in plateletpheresis donors
Authors: Kim H. J. , Kim N. C. , Park C. W. 
Published: March 2008

Background and Objectives  Plateletpheresis is the most frequent type of apheresis, with demand for these products continuously increasing. Hypothermia is a common side‐effect of apheresis, which may have an effect on the donor's body functions. The aim of this study was to examine the effects of warming methods on plateletpheresis donors’ temperature, cardiac function and cytokines.Materials and Methods  Fifty plateletpheresis donors were randomly assigned to a control group (n = 25) or a warming group (n = 25), with air and blood warmers during plateletpheresis. The effects of the treatment were examined by comparing body temperature, heart rate, blood pressure, Holter EKG pattern, serum interleukin‐1β (IL‐1β), interleukin‐2 (IL‐2), tumour necrosis factor‐α (TNF‐α) concentration, the white blood count, the white blood fraction, and the platelet count at a point in time between the two groups.Results  In the control group, the tympanic temperature decreased more during apheresis compared to the warming group (P = 0·014). The decrease of diastolic blood pressure was significantly greater in the control group compared to the warming group (P = 0·010). As for cardiac function, the frequency of abnormal beats was generally higher in the control group, but the difference was not significant. IL‐2 and TNF‐α decreased significantly after plateletpheresis in the control group only, while there was no change in the warming group.Conclusion  The decrease of temperature during plateletpheresis resulted in changes in haemodynamics and cytokines. The warming methods used in this study can prevent the decrease of temperature in donors, and may be helpful in maintaining the haemodynamic and cytokine balance.