bluuebunny/crossref_metadata_2025_split huggingface dataset:
How do Regulatory T Cells Work?
Authors: Corthay A. 
Published: July 2009

AbstractCD4+ T cells are commonly divided into regulatory T (Treg) cells and conventional T helper (Th) cells. Th cells control adaptive immunity against pathogens and cancer by activating other effector immune cells. Treg cells are defined as CD4+ T cells in charge of suppressing potentially deleterious activities of Th cells. This review briefly summarizes the current knowledge in the Treg field and defines some key questions that remain to be answered. Suggested functions for Treg cells include: prevention of autoimmune diseases by maintaining self‐tolerance; suppression of allergy, asthma and pathogen‐induced immunopathology; feto‐maternal tolerance; and oral tolerance. Identification of Treg cells remains problematic, because accumulating evidence suggests that all the presently‐used Treg markers (CD25, CTLA‐4, GITR, LAG‐3, CD127 and Foxp3) represent general T‐cell activation markers, rather than being truly Treg‐specific. Treg‐cell activation is antigen‐specific, which implies that suppressive activities of Treg cells are antigen‐dependent. It has been proposed that Treg cells would be self‐reactive, but extensive TCR repertoire analysis suggests that self‐reactivity may be the exception rather than the rule. The classification of Treg cells as a separate lineage remains controversial because the ability to suppress is not an exclusive Treg property. Suppressive activities attributed to Treg cells may in reality, at least in some experimental settings, be exerted by conventional Th cell subsets, such as Th1, Th2, Th17 and T follicular (Tfh) cells. Recent reports have also demonstrated that Foxp3+ Treg cells may differentiate in vivo into conventional effector Th cells, with or without concomitant downregulation of Foxp3.
Functional characterization of CCA1/LHY homolog genes, PpCCA1a and PpCCA1b, in the moss Physcomitrella patens
Authors: Okada Ryo , Kondo Sayo , Satbhai Santosh B. , Yamaguchi Nobutoshi , Tsukuda Masashi , Aoki Setsuyuki 
Published: July 2009

SummaryThe evolution of circadian clocks in land plants is not understood, because circadian rhythms have received little attention in plants other than angiosperms. We have characterized two genes, PpCCA1a and PpCCA1b, homologs of the Arabidopsis thaliana clock genes CCA1/LHY, from the moss Physcomitrella patens. PpCCA1a and PpCCA1b, together with angiosperm CCA1/LHY homologs, belong to the clock‐associated single‐myb gene family of green plants (including green algae and land plants). The accumulation of PpCCA1a and PpCCA1b mRNA showed rhythms with a period of approximately 1 day, phased as are those of angiosperm homologs, under 24 h light/dark cycles or in continuous dark. However, in marked contrast to angiosperm homologs, both genes showed arrhythmic profiles in continuous light. The timing of the PpCCA1b peak is determined by the time of the last light to dark transition, suggesting that the arrhythmicity in continuous light is due to dysfunction of the core clock. We generated single and double disruptants for PpCCA1a and PpCCA1b, and found that the double disruptants showed: (i) short periodicity and damped amplitude in the PpCCA1b rhythm, (ii) similar changes in the rhythmically expressed genes PpSIG5 and PpPRRa, and (iii) de‐repression of PpCCA1b transcription levels, indicating negative feedback regulation. These observations indicate that the two genes are not merely structural homologs but also functional counterparts of CCA1/LHY. Together, our results illustrate similarities as well as divergence of the clock machineries between P. patens and A. thaliana, two distantly placed species in land plant phylogeny.
Targeted metabolite and transcript profiling for elucidating enzyme function: isolation of novel N‐methyltransferases from three benzylisoquinoline alkaloid‐producing species
Authors: Liscombe David K. , Ziegler Jörg , Schmidt Jürgen , Ammer Christian , Facchini Peter J. 
Published: July 2009

SummaryAn integrated approach using targeted metabolite profiles and modest EST libraries each containing approximately 3500 unigenes was developed in order to discover and functionally characterize novel genes involved in plant‐specialized metabolism. EST databases have been established for benzylisoquinoline alkaloid‐producing cell cultures of Eschscholzia californica, Papaver bracteatum and Thalictrum flavum, and are a rich repository of alkaloid biosynthetic genes. ESI‐FTICR‐MS and ESI‐MS/MS analyses facilitated unambiguous identification and relative quantification of the alkaloids in each system. Manual integration of known and candidate biosynthetic genes in each EST library with benzylisoquinoline alkaloid biosynthetic networks assembled from empirical metabolite profiles allowed identification and functional characterization of four N‐methyltransferases (NMTs). One cDNA from T. flavum encoded pavine N‐methyltransferase (TfPavNMT), which showed a unique preference for (±)‐pavine and represents the first isolated enzyme involved in the pavine alkaloid branch pathway. Correlation of the occurrence of specific alkaloids, the complement of ESTs encoding known benzylisoquinoline alkaloid biosynthetic genes and the differential substrate range of characterized NMTs demonstrated the feasibility of bilaterally predicting enzyme function and species‐dependent specialized metabolite profiles.
Field evaluation of Crystal VC® Rapid Dipstick test for cholera during a cholera outbreak in Guinea‐Bissau
Authors: Harris Julie R. , Cavallaro Elizabeth C. , De Nóbrega Aglaêr A. , Dos S. Barrado Jean C. B. , Bopp Cheryl , Parsons Michele B. , Djalo Djulde , Fonseca Fatima G. da S. , Ba Umaro , Semedo Agostinho , Sobel Jeremy , Mintz Eric D. 
Published: July 2009

SummaryObjectives  To evaluate performance characteristics and ease of use of the new commercially available Crystal VC® Rapid Dipstick (VC) test (Span Diagnostics, India) for Vibrio cholerae O1 and O139.Methods  Whole stool was collected from patients presenting to a hospital cholera ward during a 2008 epidemic in Guinea‐Bissau. The VC test on stool samples was conducted on‐site; samples were subsequently stored in Cary‐Blair transport media and sent to the Centers for Disease Control and Prevention for diagnostic testing by culture and polymerase chain reaction (PCR). In addition, four local laboratory technicians who were unfamiliar with the test were provided with stool samples, the VC test kit, and simple written instructions and asked to perform the test and interpret results.Results  A total of 101 stool specimens were collected and tested. Compared with PCR, the test was 97% sensitive and 71–76% specific. Laboratory technicians in Bissau performed the test and interpreted results correctly using only simple written instructions.Conclusions  The VC test may be useful for cholera diagnosis in outbreak situations where laboratory capacity is limited.
Yield performances of japonica introgression lines selected for drought tolerance in a BC breeding programme
Authors: He Y. X. , Zheng T. Q. , Hao X. B. , Wang L. F. , Gao Y. M. , Hua Z. T. , Zhai H. Q. , Xu J. L. , Xu Z. J. , Zhu L. H. , Li Z. K. 
Published: July 2009

With 5 tables AbstractDeveloping drought tolerant cultivars is a preferred strategy to solve water‐shortage facing rice farmers. A backcross (BC) breeding was initiated to improve drought tolerance (DT) of japonica hybrids in North China using an elite japonica restorer, C418, as recipient and five indica cultivars as donors. A two‐round‐selection for yield under severe drought together with a two‐round‐selection for yield under irrigation resulted in 113 BC2F8 introgression lines (ILs). Progeny testing allowed the identification of 46 (40.7%) superior‐C418‐ILs that had significantly improved yield potential under water stress and/or normal irrigation, demonstrating the power of BC breeding in exploiting favourable variation hidden in the indica gene pool for improving complex traits of japonica rice. Increased height and accelerated‐heading were major phenotypic changes correlated with improved‐yield under stress in these ILs, suggesting the possible involvement of gibberellin (GA) pathway and drought escaping. Considerable variations in yield components among these ILs indicate the presence of different underlying mechanisms. The C418‐ILs developed in this study provide useful materials for dissecting DT and yield, and for further target‐trait‐improvement by pyramiding.
Northern Barbados accretionary prism: Structure, deformation, and fluid flow interpreted from 3D seismic and well‐log data
Authors: Cukur Deniz , Lee Gwang H. , Um Jeong G. , Kim Dae C. , Kim Jin H. 
Published: July 2009

AbstractWe reanalyzed 3D seismic reflection and logging‐while‐drilling data from the toe of the northern Barbados accretionary prism to interpret structure, deformation, and fluid flow related to subduction processes. The seafloor amplitude and coherence reveal an abrupt change in the thrust orientation from NNE at the thrust front and north and NNW about 5 km west of the thrust front. These thrust sets are separated by a triangular‐shaped quiet area, which may represent a zone of low strength. The northeast‐trending band of strong negative amplitude and high coherence in the décollement, known to be an interval of arrested consolidation, overlaps the quiet area, suggesting that the arrested consolidation may be related to the lack of thrust imbrication, and thus, vertical drainage for fluid in the accretionary prism. Fractal analysis of the décollement and top of the subducting oceanic basement indicates that the relief of the décollement correlates with the topography of the oceanic basement. Differential compaction of the underthrust sediment overlying the rugged oceanic basement, together with the basement faults that penetrate into the décollement probably caused relief or even faulting in the décollement.
Spermiogenesis and spermatozoal ultrastructure in Trichomycteridae (Teleostei: Ostariophysi: Siluriformes)
Authors: Spadella Maria Angélica , Oliveira Claudio , Quagio‐Grassiotto Irani 
Published: July 2009

AbstractSpadella, M.A., Oliveira, C. and Quagio‐Grassiotto, I. 2009. Spermiogenesis and spermatozoal ultrastructure in Trichomycteridae (Teleostei: Ostariophysi: Siluriformes). —Acta Zoologica (Stockholm) 91: 373–389.Siluriformes comprises the most diverse and widely distributed ostariophysan group, a fish assemblage that includes about three quarters of the freshwater fish of the world. In this study, the ultrastructural characterization of spermiogenesis and spermatozoa in specimens of Copionodontinae (the sister group to all other trichomycterids), Trichomycterinae (a derived trichomycterid group), and Ituglanis (a genus not assigned to any trichomycterid subfamily) is presented. The comparative analyses of the data show that trichomycterid species share six of seven analyzed spermiogenesis characters, reinforcing the monophyly of the group. Analyses of trichomycterid sperm ultrastructure showed that the species studied share the same character states for nine of seventeen characters analyzed. Copionodon orthiocarinatus and Ituglanis amazonicus each share more ultrastructural characters with species of Trichomycterus than with one another. Regarding the families of Loricarioidea, the species of Trichomycteridae share more characters of spermatogenesis, spermiogenesis, and sperm with representatives of the families Callichthyidae, Loricariidae, and Scoloplacidae than with Nematogenyidae, its hypothesized sister group. With the exception of the family Nematogenyidae, the character similarities observed reinforce the monophyly of the superfamily Loricarioidea.
The Role of Situational Interviews in Fostering Positive Reactions to Selection Decisions
Authors: Seijts Gerard H. , Kyei‐Poku Ivy 
Published: July 2009

We investigated the effect of interview format and employment equity program strength on perceptions of fairness. We used job seekers and vignettes to test the hypotheses. The participants reported lukewarm support for employment equity programs. The use of a situational interview in the selection process of an organisation that had adopted an employment equity program contributed to higher perceptions of fairness vis‐à‐vis the use of an unstructured interview. The results also showed that the inclusion of a situational interview in the selection process mitigated negative reactions to the selection decision when a strong employment equity program was in place as well as when a female visible minority was hired.Nous avons évalué l'impact sur la perception de justice du style d'entretien et de la rigueur d'une charte d'équité relative à l'emploi. On a fait appel à des demandeurs d'emploi et utilisé un test de jugement situationnel pour éprouver les hypothèses. Les répondants se sont montrés peu enthousiastes en ce qui concerne les chartes d'équité relatives à l'emploi. Le choix d'un entretien structuré dans le processus de sélection d'une organisation qui avait adopté une charte d'équité relative à l'emploi a amélioré la perception de justice portant sur un entretien ordinaire. Il apparaît aussi que la présence d'un entretien structuré dans le processus de sélection atténuait les réactions négatives consécutives au résultat de la sélection quand existait une sérieuse charte d'équité relative à l'emploi et quand était embauchée une minorité féminine non négligeable.
Differences in the free Ca2+ in undiluted urine from stone formers and normal subjects using a new generation of ion‐selective electrodes
Authors: Langley S.E.M. , Fry C.H. 
Published: July 2009

Objectives To measure the ionized Ca2+ in urine from normal subjects and patients with urinary tract stones. Patients and methods Urine samples were obtained from 37 normal subjects and 52 stone‐formers. Ca2+ was measured using plastic dip‐cast ion‐selective electrodes; total Ca and other variables were measured by standard analytical techniques. Results The ionized Ca2+ and the total Ca were greater in stone‐formers' urine although the difference was more significant with the Ca2+ data, especially at a standardized pH. Absolute values of the Ca2+ were dependent on the type of reference electrode used. The Ca2+ was a function of urine pH; lower values were recorded as pH increased. Measured values of the Ca2+ did not correlate well with calculated values using a standard computer program. Conclusions Measurement of the Ca2+ in spot urine samples at a standard pH provides a more discriminative test than total Ca for the presence of urinary tract stones. The pH dependence of the Ca2+ may have important consequences in the formation of urinary tract stones. The poor correlation between measured and computed values of Ca2+ emphasizes the importance of accurate measurement of this variable.
pEAQ: versatile expression vectors for easy and quick transient expression of heterologous proteins in plants
Authors: Sainsbury Frank , Thuenemann Eva C. , Lomonossoff George P. 
Published: July 2009

SummaryAgro‐infiltration of leaf tissue with binary vectors harbouring a sequence of interest is a rapid method of expressing proteins in plants. It has recently been shown that flanking the sequence to be expressed with a modified 5′‐untranslated region (UTR) and the 3′‐UTR from Cowpea mosaic virus (CPMV) RNA‐2 (CPMV‐HT) within the binary vector pBINPLUS greatly enhances the level of expression that can be achieved [Sainsbury, F. and Lomonossoff, G.P. (2008)Plant Physiol. 148, 1212–1218]. To exploit this finding, a series of small binary vectors tailored for transient expression (termed the pEAQ vectors) has been created. In these, more than 7 kb of non‐essential sequence was removed from the pBINPLUS backbone and T‐DNA region, and unique restriction sites were introduced to allow for accommodation of multiple expression cassettes, including that for a suppressor of silencing, on the same plasmid. These vectors allow the high‐level simultaneous expression of multiple polypeptides from a single plasmid within a few days. Furthermore, vectors have been developed which allow the direct cloning of genes into the binary plasmid by both restriction enzyme‐based cloning and GATEWAY recombination. In both cases, N‐ or C‐terminal histidine tags may be fused to the target sequence as required. These vectors provide an easy and quick tool for the production of milligram quantities of recombinant proteins from plants with standard plant research techniques at a bench‐top scale.
On Wittgenstein's Notion of Meaning‐Blindness: Its Subjective, Objective and Aesthetic Aspects
Authors: Wenzel Christian Helmut 
Published: July 2009

Abstract
Das Aussprechen eines Wortes ist gleichsam ein Anschlagen einer Taste auf dem Vorstellungsklavier. (Uttering a word is like striking a note on the keyboard of the imagination.) (PU §6)Polonius: What do you read, my lord?Hamlet: Words, words, words!(Hamlet, act 2, scene 2)
Wittgenstein in his later years thought about experiences of meaning and aspect change. Do such experiences matter? Or would a meaning‐ or aspect‐blind person not lose much? Moreover, is this a matter of aesthetics or epistemology? To get a better perspective on these matters, I will introduce distinctions between certain subjective and objective aspects, namely feelings of our inner psychological states versus fine‐tuned objective experiences of the outer world. It seems to me that in his discussion of meaning‐blindness, Wittgenstein unhappily floats between these two extremes, the subjective and the objective. I will also introduce some notions from Kant's aesthetics, to get a better understanding of the interplay between feeling and meaning. This will shed some new light on Wittgenstein's enquiry into meaning‐ and aspect‐blindness.
Importance of sunscreen products spreading protocol and substrate roughness for in vitro sun protection factor assessment
Authors: Fageon L. , Moyal D. , Coutet J. , Candau D. 
Published: July 2009

SynopsisThe purpose of this study was to evaluate the impact of substrate roughness and of product spreading method on in vitro sun protection factor (SPF) measurement and to define the experimental conditions most appropriate to reach the best level of correlation to in vivo SPF. In vitro SPF assessment was carried out on 13 products (including different formulation types with SPF from 20 to 75) using various in vitro SPF protocols and comparing related predictive potential regarding in vivo SPF. In the first part, two spreading methods were compared on two types of PMMA (Polymethyl methacrylate plate with different roughness. The impact of a second spreading step after product drying was also evaluated. From the various investigated parameters, it was shown that (i) a higher roughness (Ra = 4, 5 μm) was preferred for O/W formulations (ii) using a defined sequence of light linear and circular strokes was more adequate than monitoring product spreading in terms of time and pressure (iii) both correlation to in vivo SPF and results variability were improved when a second spreading step was added. The altered protocol showed a good predictive potential regarding in vivo SPF values for O/W formulations (correlation coefficient 0.92, correlation curve slope 0.98) and coefficient of variation of in vitro results (14% of the mean SPF value) close to what is usually obtained in vivo. The repeatability of the protocol was also demonstrated. In the second part, we evaluated the impact of PMMA plate pre‐treatment with paraffinum liquidum before spreading the product to get a better correlation between in vivo and in vitro SPF values for W/O formulations. This allowed us to define a protocol suitable for both O/W and W/O formulations.
Scaling of plantar pressures in mammals
Authors: Michilsens F. , Aerts P. , Van Damme R. , D'Août K. 
Published: July 2009

AbstractThe interaction of the limbs with the substrate can teach a lot about an animal's gait mechanics. Unlike ground‐reaction forces, plantar pressure distributions are rarely studied in animals, but they may provide more detailed information about the loading patterns and locomotor function of specific anatomical structures. With this study, we aim to describe pressures for a large and diverse sample of mammalian species, focusing on scaling effects. We collected dynamic plantar pressure distributions during voluntary walking in 28 mammal species. A dynamic classification of foot use was made, which distinguished between plantiportal, digitiportal and unguliportal animals. Analysis focused on scaling effects of peak pressures, peak forces and foot contact areas. Peak pressure for the complete mammal sample was found to scale to (mass)1/2, higher than predicted assuming geometric similarity, and we found no difference between the different types of foot use. Only the scaling of peak force is dependent on the dynamic foot use. We conclude that plantar peak pressure rises faster with mass than expected, regardless of the type of foot use, and scales higher than in limb bones. These results might explain some anatomical and behavioural adaptations in graviportal animals.
Mutations of cytosolic loop residues impair assembly and maturation of α7 nicotinic acetylcholine receptors
Authors: Mukherjee Jayanta , Kuryatov Alexander , Moss Stephen J. , Lindstrom Jon M. , Anand Rene 
Published: July 2009

AbstractMechanisms that regulate early events in the biogenesis of the α7 nicotinic acetylcholine receptor (α7 AChR) are not well understood. Data presented here show that single amino acid mutations in the cytoplasmic loop of the α7 AChR, between position 335 and 343, abolish or attenuate expression of mature pentameric α7 AChRs in both human embryonic kidney tsA201 (HEK) and neuronal SH‐SY5Y cells. Although the number of mature α7 AChRs is increased significantly in the presence of the chaperone protein resistant to inhibitors of cholineesterase‐3 in HEK cells, sucrose gradient sedimentation reveals that the vast majority of α7 subunits are aggregated or improperly assembled. Transfection of α7 AChRs in SH‐SY5Y cells, which endogenously express the α7 AChR, results in a much larger fraction of subunits assembled into mature AChRs. Thus, efficient assembly of α7 AChRs is influenced by several regions of the large cytoplasmic domain, as well perhaps by other parts of its structure, and requires as yet unknown factors not required by other AChR subtypes.
Agonist‐induced internalization of mGluR1α is mediated by caveolin
Authors: Hong Yun Hwa , Kim Ji Young , Lee Jeong Ho , Chae Hong Gu , Jang Sung Soo , Jeon Ju Hong , Kim Chul Hoon , Kim Jun , Kim Sang Jeong 
Published: July 2009

AbstractAgonist‐induced internalization of metabotropic glutamate receptors (mGluRs) plays an important role in neuronal signaling. Although internalization of mGluRs has been reported to be mediated by clathrin‐dependent pathway, studies describing clathrin‐independent pathways are emerging. Here, we report that agonist‐induced internalization of mGluR1α is mediated by caveolin. We show that two caveolin‐binding motifs of mGluR1α interact with caveolin1/2. Using cell surface‐immunoprecipitation and total internal reflection fluorescence imaging, we found that agonist‐induced internalization of mGluR1α is regulated by caveolin‐binding motifs of the receptor in heterologous cells. Moreover, in the cerebellum, group I mGluR agonist dihydroxyphenylglycol increased the interaction of phosphorylated caveolin with mGluR1α. This interaction was blocked by methyl‐β‐cyclodextrin, known to disrupt caveolin/caveolae‐dependent signaling by cholesterol depletion. Methyl‐β‐cyclodextrin also blocked the agonist‐induced internalization of mGluR1α. Thus, these findings represent the evidence for agonist‐induced internalization of mGluR1α via caveolin and suggest that caveolin might play a role in synaptic metaplasticity by regulating internalization of mGluR1α in the cerebellum.