bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surfactant Protein A Integrates Activation Signal Strength To Differentially Modulate T Cell Proliferation
Authors: Mukherjee Sambuddho , Giamberardino Charles , Thomas Joseph , Evans Kathy , Goto Hisatsugu , Ledford Julie G. , Hsia Bethany , Pastva Amy M. , Wright Jo Rae 
Published: January 2012

AbstractPulmonary surfactant lipoproteins lower the surface tension at the alveolar–airway interface of the lung and participate in host defense. Previous studies reported that surfactant protein A (SP-A) inhibits lymphocyte proliferation. We hypothesized that SP-A–mediated modulation of T cell activation depends upon the strength, duration, and type of lymphocyte activating signals. Modulation of T cell signal strength imparted by different activating agents ex vivo and in vivo in different mouse models and in vitro with human T cells shows a strong correlation between strength of signal (SoS) and functional effects of SP-A interactions. T cell proliferation is enhanced in the presence of SP-A at low SoS imparted by exogenous mitogens, specific Abs, APCs, or in homeostatic proliferation. Proliferation is inhibited at higher SoS imparted by different doses of the same T cell mitogens or indirect stimuli such as LPS. Importantly, reconstitution with exogenous SP-A into the lungs of SP-A−/− mice stimulated with a strong signal also resulted in suppression of T cell proliferation while elevating baseline proliferation in unstimulated T cells. These signal strength and SP-A–dependent effects are mediated by changes in intracellular Ca2+ levels over time, involving extrinsic Ca2+-activated channels late during activation. These effects are intrinsic to the global T cell population and are manifested in vivo in naive as well as memory phenotype T cells. Thus, SP-A appears to integrate signal thresholds to control T cell proliferation.
Development and Function of Murine B Cells Lacking RANK
Authors: Perlot Thomas , Penninger Josef M. 
Published: January 2012

Abstract
RANKL–RANK signaling regulates numerous physiologic processes such as bone remodeling, lymph node organogenesis, central thermoregulation, and formation of a lactating mammary gland in pregnancy. Recently, a receptor activator of NF-κB ligand (RANKL)-blocking Ab has been approved for human use in potentially millions of osteoporosis and cancer patients. However, germline deficiencies in RANKL or receptor activator of NF-κB (RANK) also lead to strong B cell defects in mice and human patients, suggesting that RANKL–RANK inhibition could interfere with B cell physiology and thereby trigger immunologic side-effects. To address this key question—that is, whether RANKL–RANK signaling affects B cell physiology directly or the observed defects are secondary because of the severe osteopetrosis—we generated B cell-specific RANK knockout mice. We show that B cells deficient for RANK undergo normal development and do not show any obvious defects in Ab secretion, class switch recombination, or somatic hypermutation. Our data indicate that ablation of the RANKL–RANK pathway has no direct adverse effect on B cell physiology.
Afirmação originária e sabedoria prática na reflexão ética de Paul Ricœur
Authors: Portocarrero Maria Luísa 
Published: January 2012

This paper´s aim is to outline the foundation of Paul Ricœur´s ethics, which we believe to be a hermeneutical experience of recognition of existence´s original claim, a thesis that he takes from his master Jean Nabert. Although the question of recognition appears only in the last work of Ricœur, we hold that it is already present since the earliest works, particularly in The Symbolism of Evil, insofar as, through symbolic language, the contrasting experience of evil leads to the whole hermeneutical process of recognition and interpretation of an original affirmation, despite evil. The very theme of man´s capability, including the issue of self-esteem, shall be understood on the basis of this original affirmation, which reveals his plural condition in the plan of responsibility in the context of applied ethics.
GSTM1 and GSTP1 gene variants and the effect of air pollutants on lung function measures in South African children
Authors: Reddy Poovendhree , Naidoo Rajen N. , Robins Thomas G. , Mentz Graciela , Li Huiling , London Stephanie J. , Batterman Stuart 
Published: January 2012

AbstractBackgroundSeveral genes are associated with an increased susceptibility to asthma, which may be exacerbated by ambient air pollution. These genes include GSTM1 (glutathione‐S‐transferase M1 gene) and GSTP1 (glutathione‐S‐transferase P1 gene), which may modulate the response to epithelial oxidative changes caused by air pollutant exposure. This study evaluated fluctuations in the forced expiratory volume in one second (FEV1) in relation to lagged daily averages of ambient air pollutants (SO2, NO2, NO, and PM10) while considering genotype as an effect modifier.MethodsA longitudinal cohort of 129 schoolchildren of African descent from Durban, South Africa was assessed. GSTM1 (null vs. present genotype) and GSTP1 (Ile105Val; AA → AG/GG) genotypes were determined using standard techniques. SO2, NO2, NO, and PM10 were measured continuously over a year using validated methods. The outcome was intraday variability in FEV1. Data were collected daily over a 3‐week period in each of four seasons (2004–2005).ResultsAmong the children tested, 27% had the GSTM1 null genotype and 81% carried the GSTP1 G allele. Approximately 26 out 104 children (25%) showed evidence of bronchial hyperreactivity, 13% reported having symptoms in keeping with persistent asthma, and a further 25% reported symptoms of mild intermittent asthma. PM10 and SO2 levels were moderately high relative to international guidelines. Neither GSTM1 nor GSTP1 genotypes alone were significantly associated with FEV1 intraday variability. In models not including genotype, FEV1 variability was statistically significantly associated only with NO2 for 5‐day lags (% change in intraday variability in FEV1 per interquartile range = 1.59, CI 0.58, 2.61). The GSTP1 genotype modified the effect of 3 days prior 24‐hr average PM10 and increased FEV1 variability. A similar pattern was observed for lagged 3 day SO2 exposure (P interaction < 0.05). Adverse effects of these pollutants were limited to individuals carrying the G allele for this polymorphism.ConclusionAmong this indigenous South African children cohort, the GSTP1 genotype modified the effects of ambient exposures to PM10 and SO2 and lung function. A plausible mechanism for these observed effects is decreased capacity to mount an effective response to oxidative stress associated with the GSTP1 AG + GG genotype. Am. J. Ind. Med. 55:1078–1086, 2012. © 2012 Wiley Periodicals, Inc.
Influence of the surface hydrolysis on the functionality of poly(ethylene terephthalate) fabric treated with nanotitanium dioxide
Authors: Hashemizad Shiva , Montazer Majid , Rashidi Abosaied 
Published: January 2012

AbstractIn this study, the polyester (PET) fabric was hydrolyzed with alkali to increase the surface activity and enhance the nano titanium dioxide (nano‐TiO2) adsorption to produce higher functionality. The PET fabric was first treated with sodium hydroxide along with cetyl trimethyl ammonium bromide as a cationic surfactant and then dipped into an ultrasound bath containing nano‐TiO2followed by curing at high temperature. The weight loss, vertical wicking, and water droplet adsorption time were evaluated and are reported. The photocatalytic activity of TiO2nanoparticles deposited on the PET fabric was examined by the degradation of methylene blue as a model stain under daylight irradiation. The residual TiO2on the fabric surface after 1 and 10 successive washings was determined to indicate the washing durability of the finished fabric. Also, the UV protection was assessed by UV reflectance spectroscopy. The scanning electron microscopy pictures and energy‐dispersive X‐ray spectra of some fabrics are also reported. The surface hydrolysis of the PET fabric with sodium hydroxide created some voids and hydrophilic groups on the fabric surface; this led to the higher adsorption of nano‐TiO2particles and enhanced the wettability, vertical wicking, and higher durability against repeated washings of the nano‐TiO2treated fabric. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
The Shrinking World of Innocent Ligands: Conventionaland Non‐Conventional Redox‐Active Ligands
Authors: Kaim Wolfgang 
Published: January 2012

AbstractThis essay for EurJIC's cluster issue on cooperative and redox non‐innocent ligands introduces the reader to redox‐active ligands, which range from the small archetypical NO+/•/– and O20/•–/2–systems via the classical 1,4‐dihetero‐1,3‐diene chelates (e.g. α‐diimine, dithiolene, or o‐quinone redox series) to π‐conjugated macrocycles. The increased attention paid recently to the redox activity of ligands in coordination chemistry has now prompted wider successful searches, resulting in the establishing of less‐conventional examples such as cyanide, carbon monoxide, thioethers, or acetylacetonate derivatives as non‐innocently behaving ligands. By considering situations with significantly covalent metal–ligand bonding, the cases of metal–oxo, metal–hydrido, and organometallic compounds will also be addressed, with a perspective on how pervasive non‐innocent ligand behavior is. The materials and reactivity potential of redox‐active ligands will be pointed out.
Time‐selective chemoprevention of vitamin E and selenium on esophageal carcinogenesis in rats: The possible role of nuclear factor kappaB signaling pathway
Authors: Yang Hui , Jia Xudong , Chen Xiaoxin , Yang Chung S. , Li Ning 
Published: January 2012

AbstractPrevious human intervention trial demonstrated that vitamin E (Ve) and selenium (Se) supplementation decreased esophageal cancer deaths among younger participants, but may have no effect or produce an opposite effect among older ones. In our study, we intended to mimic this human nutritional trial to determine the chemopreventive effects of Ve/Se supplementation at the early or late stage of esophageal carcinogenesis in rats. Esophageal squamous cell carcinoma (ESCC) was induced in Fischer 344 rats with N‐nitrosomethylbenzylamine (NMBzA, 0.35 mg/kg BW, s.c., three times per week for 5 weeks). The rats were maintained on a modified AIN‐93M diet with low levels of Ve/Se or supplemented with high levels of Ve/Se at different stages. At Week 25, the number and volume of visible tumors, the numbers of dysplasia and ESCC were significantly lower in rats of supplementation during the early stage (Group C) or during the entire experimental period (Group E), but not during the late stage (Group D). Ve/Se supplementation at the early stage also significantly decreased cell proliferation, nuclear factor kappaB (NFκB) activation, protein and mRNA expression of cyclooxygenase 2 and 5‐lipoxygenase and biosynthesis of prostaglandin E2 and leukotriene B4 during the carcinogenesis of rat esophagus. Our results demonstrated that the chemopreventive efficacy of Ve/Se supplementation on NMBzA‐induced esophageal cancer is time selective and that supplementation during the early stage is clearly effective but probably ineffective during the late stage of carcinogenesis. NFκB signaling pathway activation and aberrant arachidonic acid metabolism might be the underlying mechanism.
MED12 mutations in uterine fibroids—their relationship to cytogenetic subgroups
Authors: Markowski Dominique Nadine , Bartnitzke Sabine , Löning Thomas , Drieschner Norbert , Helmke Burkhard Maria , Bullerdiek Jörn 
Published: January 2012

AbstractRecurrent chromosomal alterations are found in roughly 20% of all uterine fibroids but in the majority cytogenetic changes are lacking. Recently, mutations of the gene mediator subcomplex 12 (MED12) have been detected in a majority of fibroids but no information is available whether or not they co‐occur with cytogenetic subtypes as, e.g., rearrangements of the genes encoding high mobility group AT‐hook (HMGA) proteins. In a total of 80 cytogenetically characterized fibroids from 50 patients, we were not only able to confirm the frequent occurrence of MED12 mutations but also to stratify two mutually exclusive pathways of leiomyomagenesis with either rearrangements of HMGA2 reflected by clonal chromosome abnormalities affecting 12q14∼15 or by mutations affecting exon 2 of MED12. On average the latter mutations were associated with a significantly smaller tumor size. However, G>A transitions of nucleotides c.130 or c.131 correlate with a significantly larger size of the fibroids compared to other MED12 mutations thus explaining the high prevalence of the former mutations among clinically detectable fibroids. Interestingly, fibroids with MED12 mutations expressed significantly higher levels of the gene encoding wingless‐type MMTV integration site family, member 4 (WNT4). Based on these findings and data from the literature, we hypothesize that estrogen and the mutated MED12 cooperate in activating the Wnt pathway which in turn activates β‐catenin known to cause leiomyoma‐like lesions in a mouse model. The occurrence of a “fibroid‐type mutation” in a rare histologic subtype of endometrial polyps suggests that this mechanism is not confined to uterine leiomyomas.
A discriminative Ramachandran potential of mean force aimed at minimizing secondary structure bias
Authors: Koppole Sampath , Schaefer Michael 
Published: January 2012

AbstractWe introduce PMF*, a novel potential of mean force (PMF) for the Ramachandran ϕ/Ψ dihedral plot of the 20 standard amino acids and assess its relevance to the conformation of polypeptides by scoring structures in the protein data bank and decoy datasets. The new energy function is a linear combination of the conventional, unreferenced PMF and the ΔPMF relative to the free energy of all amino acids in the parameterization set of structures, effectively removing their respective biases toward α‐helix and β‐strand. It is shown that low‐resolution crystal structures, NMR structures, and theoretical models have on average significantly higher energies than high‐resolution crystal structures; also PMF* is more discriminative for structure quality than the individual PMF and ΔPMF energy functions. PMF* may be well suited for use as a restraint energy term in the refinement of experimental structures and theoretical models. © 2012 Wiley Periodicals, Inc.
Purification of diamine oxidase and its properties in germinated fava bean (Vicia faba L.)
Authors: Yang Runqiang , Chen Hui , Han Yongbin , Gu Zhenxin 
Published: January 2012

AbstractBackground: γ‐Aminobutyric acid (GABA) is a non‐protein amino acid with bioactive functions for human health. Diamine oxidase (DAO, EC 1.4.3.6) is one of the key enzymes for GABA formation. In the present study, this enzyme was purified from 5 day germinated fava bean and its properties were investigated in vitro.Results: The molecular mass of the enzyme estimated by Sephadex G‐100 gel filtration was 121 kDa. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) displayed a single band at a molecular mass of 52 kDa. The enzyme had optimal activity at 40 °C and retained its activity after being incubated at 30 °C for 30 min. It showed higher activity at pH 6.5 than at other pH values. The enzyme was significantly inhibited by Mg2+, Cu2+, Fe3+, aminoguanidine, ethylene glycol tetraacetic acid (EGTA), ethylene diamine tetraacetic acid disodium salt (EDTA‐Na2), L‐cysteine and β‐mercaptoethanol. The Km value of DAO was 0.23 mmol L−1 for putrescine and 0.96 mmol L−1 for spermidine. However, the enzyme did not degrade spermine.Conclusion: DAO from germinated fava bean was purified. The optimal reaction temperature and pH of the enzyme were mild. The enzyme had higher affinity to putrescine than to spermidine and spermine. Copyright © 2011 Society of Chemical Industry
Stopover duration of fall‐migrating dabbling ducks
Authors: O'Neal Benjamin J. , Stafford Joshua D. , Larkin Ronald P. 
Published: January 2012

AbstractThe amount of time migrating birds spend at stopover sites, or stopover duration, partially determines an individual's access to resources, the environmental conditions encountered, and the exposure to predation, which in turn affect survival and fecundity. As such, migratory behaviors such as stopover duration can have a considerable effect on populations of migrants and plans for their conservation. This is especially true for migrant waterfowl, which are explicitly conserved through Joint Venture (JV) partnerships under the North American Waterfowl Management Plan. Although waterfowl are one of the most heavily studied taxa, little is known about their stopover behavior due to the scope of migration. Consequently, conservation plans of many mid‐migration JVs either omit estimates of stopover duration or rely on antiquated data to estimate energetic requirements. We used weather surveillance radar to identify and enumerate ducks emigrating from an important stopover area in central Illinois. By using radar data in combination with data from weekly aerial inventories, we estimated an average stopover duration for fall‐migrating dabbling ducks (tribe Anatini) of 28 days (SD = 12) over 8 years (1996, 1997, 2003, 2005–2009). Our estimate was similar to the historical estimate of 28 days (1940–1966), which serves as the primary reference for the Upper Mississippi River Great Lakes Region JV conservation plan. In addition to a corroborative mean, we also found considerable inter‐annual variation in stopover duration. Estimated annual stopover duration was correlated positively with an index of annual foraging habitat quality (Spearman's rank correlation;rs = 0.83), suggesting ducks may have assessed local conditions and adjusted the spatiotemporal course of fall migration. If the stopover behavior of fall‐migrating ducks is flexible and forage‐dependent, it is possible ducks allocate their time among sites in a somewhat ideal and optimal fashion, which could substantially affect the way resources are allocated within the spatial context of a JV region. © 2012 The Wildlife Society.
Hot moments and hot spots: Identifying factors explaining temporal and spatial variation in turtle road mortality
Authors: Cureton James C. , Deaton Raelynn 
Published: January 2012

AbstractMany conservation strategies focus on reducing the risk of road mortality. Turtles, which are highly susceptible to road mortality, exhibit life history traits that increase their vulnerability to population declines because of road mortality. Here, we use Akaike's Information Criterion to identify road mortality hot moments and hot spots for 5 turtle species (Chelydra serpentina, Pseudemys concinna, Terrapene carolina, Terrapene ornata, and Trachemys scripta). We tested 2 hypotheses: 1) Hot moments coincide with the breeding season of each species and 2) hot spots are associated with the habitat where each species is most commonly observed. As predicted, breeding season (May–Jun) explained most of the temporal variation in road mortality for all 5 species. Over 98% of all observed road mortality occurred during this 2‐month span. For C. serpentina and T. ornata, spatial variation in road mortality was best explained by the distance to the nearest water body, whereas distance to the nearest forest was the best model for T. scripta. The null model ranked best for P. concinna and T. carolina, suggesting none of our spatial models sufficiently explained mortality patterns of these 2 species. These results, coupled with previous studies, suggest that hot moments may be consistently associated with the breeding season. However, hot spots may be species‐specific, requiring conservation efforts to be targeted at certain species. © 2012 The Wildlife Society.
Disturbance regimes and mountain plover habitat in shortgrass steppe: Large herbivore grazing does not substitute for prairie dog grazing or fire
Authors: Augustine David J. , Derner Justin D. 
Published: January 2012

AbstractRestoring historical disturbance regimes to enhance habitat for grassland birds can conflict with livestock production goals and has been controversial because of uncertainty in the frequency and pattern of different disturbances prior to European settlement. We studied nesting habitat for the mountain plover (Charadrius montanus) in relation to prescribed fire, grazing by large herbivores (cattle), and grazing by black‐tailed prairie dogs (Cynomys ludovicianus) in the shortgrass steppe of northeastern Colorado. Breeding mountain plovers primarily occurred on black‐tailed prairie dog colonies or areas burned during the previous dormant season. Vegetation surrounding mountain plover nests and foraging locations was characterized by a fine‐scale mosaic of prostrate (<4 cm tall) vegetated patches interspersed with >35% bare soil in a given square meter, with this fine‐scale pattern distributed over a broad (>100‐m radius) area. Mountain plovers rarely occupied grassland lacking prairie dogs or recent fire, but those that did selected sites with similar vegetation height and bare soil exposure as sites on burns and prairie dog colonies. Vegetation structure at mountain plover‐occupied sites was also similar to random sites on burns and prairie dog colonies, but differed substantially from sites managed only with cattle. Intensive cattle grazing at twice the recommended stocking rate during spring (Mar–May) or summer (May–Oct) for 6 years produced significantly less bare soil than burns and prairie dog colonies, particularly following years with average or above‐average precipitation. Thus, intensive cattle grazing did not substitute for prairie dog grazing or fire in terms of effects on vegetation structure and mountain plover habitat. Both prescribed burning and increased size and distribution of black‐tailed prairie dog colonies appear to be effective and complementary means to manage for mountain plover breeding habitat in shortgrass steppe. Provision of mountain plover habitat has tradeoffs with traditional management for livestock production. Thus, managers need to clearly define desired outcomes for management to provide multiple ecosystem goods and services. © 2012 The Wildlife Society.
Kinetic studies of reactions of 4‐nitrobenzofuroxan with carbanions derived from benzyltriflones in methanol
Authors: Asghar Basim H. 
Published: January 2012

AbstractThis paper reports the rate measurements for the reactions of carbanions derived from benzyltriflones, 2, with 4‐nitrobenzofuroxan, 4, in methanol, to give anionic σ‐adducts. 1H NMR studies in DMSO‐d6 indicate that the products formed by the reaction of 2 and 4 in the presence of triethylamine are consistent with the products formed by the elimination of trifluoromethylsulfinic acid from σ‐adducts, initially formed by a carbanion attack at the 5 position of 4. The low value of β, which is the slope of the linear plot of log k5 versus pKa, provides evidence for the high steric requirements of the benzyltriflone anions. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 546–554, 2012