bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structural characterization and mass transfer properties of polyurethane block copolymer: influence of mixed soft segment block and crystal melting temperature
Authors: Mondal Subrata , Hu JinLian 
Published: June 2006

AbstractAn attempt has been made to investigate the influence of mixed soft segment on structure and mass transfer properties of segmented polyurethane (SPU). For this purpose polyurethane block copolymer containing soft segment such as polycaprolactone glycol (number‐average molecular weight 3000, PCL 3000), PCL 3000–polypropylene glycol (number‐average molecular weight 3000, PPG 3000), PCL 3000–polytetramethylene glycol (number‐average molecular weight 2900, PTMG 2900), PPG 3000–PTMG 2900, were synthesized using a two‐step or three‐step synthesis process. All the SPUs were modified with the hydrophilic segment, i.e. diol‐terminated poly(ethylene oxide) (number‐average molecular weight 3400, PEG 3400). Fourier‐transform infrared, wide‐angle X‐ray diffraction, differential scanning calorimetry, and dynamic mechanical thermal analysis were used to characterize the polyurethanes. The mass transfer properties were measured by equilibrium sorption and water vapor permeability measurements. Mixed blocks loosen the inter‐chain interaction due to phase mixing which decreases the crystallization of the soft segment in the resulting SPU. The crystallinity of mixed polyol block SPU increases when both polyols are crystallizable in the pure state. Highest loss tan δ value was observed for the sample containing PTMG 2900–PPG 3000 mixed soft segment due to their flexible and phase mixed structure which increases the chain mobility; this sample performed best among all four SPUs in equilibrium water sorption as well as water vapor permeability owing to their loose and nearly amorphous structure. Soft segment crystal melting further enhances the water vapor permeability significantly, which would make the membrane suitable for breathable textiles, packaging and medical applications. Copyright © 2006 Society of Chemical Industry
Update and challenges on proteomics in rice
Authors: Komatsu Setsuko , Yano Hiroyuki 
Published: June 2006

AbstractRice is not only an important agricultural resource but also a model plant for biological research. Our previous review highlighted different aspects of the construction of rice proteome database, cataloguing rice proteins of different tissues and organelle, differential proteomics using 2‐DE and functional characterization of some of the proteins identified (Komatsu, S., Tanaka, N., Proteomics 2005, 5, 938–949). In this review, the powerfulness and weaknesses of proteomic technologies as a whole and limitations of the currently used techniques in rice proteomics are discussed. The information obtained from these techniques regarding proteins modification, protein‐protein interaction and the development of new methods for differential proteomics will aid in deciphering more precisely the functions of known and/or unknown proteins in rice.
Analytical method for assessing potential dermal exposure to captan, using whole body dosimetry, in small vegetable production units in Argentina
Authors: Hughes Enrique A , Zalts Anita , Ojeda Javier J , Flores Andrea P , Glass Richard C , Montserrat Javier M 
Published: June 2006

AbstractAn analytical method has been developed that can be used to determine the potential dermal exposure (PDE) of workers to the pesticide captan in small‐scale horticultural production units. The methodology is based on the whole body dosimetry technique, using a cotton coverall and cotton gloves as sampling media, with protective clothing worn beneath the cotton media to protect the operator. The quantitative determination of captan was done by gas chromatography‐electron capture detector (GC‐ECD), with the analytical method validated by measuring limits of detection and quantification, linear ranges, sample recovery and precision. Special emphasis is placed on factors that affected the stability of captan during chromatographic determination. The data generated for potential dermal exposure are presented separately for mixing/loading and application activities. These data are compared with values obtained with visible tracers using a similar field technique. Margin of safety (MOS) values are also calculated for the agricultural procedures studied. Copyright © 2006 Society of Chemical Industry
Hazards and uptake of chitin synthesis inhibitors in bumblebees Bombus terrestris
Authors: Mommaerts Veerle , Sterk Guido , Smagghe Guy 
Published: June 2006

AbstractThis research project examined the potential hazards of a major class of insect growth regulators (IGRs) to survival, reproduction and larval growth in bumblebees Bombus terrestris L. Eight chitin synthesis inhibitors (CSIs) were tested: buprofezin, cyromazine, diflubenzuron, flucycloxuron, flufenoxuron, lufenuron, novaluron and teflubenzuron. These different IGRs, which are important in the control of pest insects in greenhouses, were applied via three different routes of exposure under laboratory conditions: dermal contact, and orally via the drinking of sugar/water and via pollen. The compounds were tested at their respective maximum field recommended concentrations (MFRC) and also in dose‐response assays to calculate LC50 values. In general, none of the CSIs showed acute worker toxicity. However, there was a dramatic reduction in brood production, especially after oral treatment with pollen and sugar/water. Conspicuously, egg fertility was reduced in all treatments with diflubenzuron and teflubenzuron. In addition to egg mortality, the worker bumblebees removed larvae from the treated nest, and in most cases these individuals were dead first‐second instars. Under a binocular microscope, such larvae showed an abnormally formed cuticle leading to mechanical weakness and death. In another series of experiments using 14C‐diflubenzuron and 14C‐flufenoxuron, cuticular penetration in workers was studied for a better understanding of the differences in toxicity. With 14C‐diflubenzuron, transovarial transport and accumulation in the deposited eggs supported the strong reproductive effects. Overall, the present results suggest that CSIs should be applied with caution in combination with bumblebees. The compatibility of each compound to be used in combination with B. terrestris is discussed in relation to calculated LC50 values, routes of uptake and effects. Copyright © 2006 Society of Chemical Industry
Seed and seedling characteristics of the Himalayan hornbeam (Carpinus viminea Wall.), India
Authors: Bhatt Jitendra , Ram Jeet 
Published: June 2006

AbstractTo study of seed and seedling characteristics, seeds of the Himalayan Hornbeam (Carpinus viminea Wall.) were collected from low and high‐elevation sites during the peak maturation period. Paired t‐tests indicated that seed weight, percentage of sound seeds, and germination were significantly greater for high‐elevation seeds whereas seed moisture (%) was low. Seedling growth performance was better for high‐elevation seeds than for those from low elevation. This indicates that environmental conditions at high elevation may favour germination and seedling growth of the species.
Pharmacological properties of Chinese hamster ovary cells coexpressing two vasoactive intestinal peptide receptors (hVPAC1 and hVPAC2)
Authors: Langer Ingrid , Gaspard Nathalie , Robberecht Patrick 
Published: June 2006

In the light of recent findings that VPAC1 and VPAC2 receptors form homodimers and heterodimers, we have evaluated the function of these receptors coexpressed in the same cells, using whole‐cell and membrane preparations. Cells expressing each receptor alone were used for comparison.The study was performed on Chinese hamster ovary cells stably transfected with both human recombinant receptors and we compared receptor occupancy and adenylate cyclase activation by VIP, Ro 25‐1553 – a VPAC2 selective agonist – and [K15,R16,L27]VIP(1‐7)/GRF(8‐27) – a VPAC1 selective agonist – on membranes prepared from each cell line and on a mixture of membranes from cells expressing each receptor individually. We also studied receptor internalization induced by the three agonists on intact cells expressing both receptors alone or together by fluorescence‐activated cell sorting using monoclonal antibodies and demonstrated by using co‐immunoprecipitation that the two receptors did interact.The results indicated that coexpression of the receptors did not modify the recognition of ligands, nor the capacity of the agonists to stimulate adenylate cyclase activity and, in intact cells, to induce internalization of the receptors.As a consequence, the properties of the selective ligands that were established on cell lines expressing a single population of VIP receptors were valid on cells expressing both receptors. Furthermore, the recently demonstrated VPAC1/VPAC2 receptor heterodimerization did not affect the function of either receptor.British Journal of Pharmacology(2006)148, 1051–1059. doi:10.1038/sj.bjp.0706816
The role of waterholes as ‘refugia’ in sustaining genetic diversity and variation of two freshwater species in dryland river systems (Western Queensland, Australia)
Authors: CARINI G. , HUGHES J. M. , BUNN S. E. 
Published: June 2006

Summary1. Episodic floods and extended low or no flow periods characterise dryland river systems in Western Queensland, Australia. During protracted intervals between floods, rivers consist of a series of isolated waterholes, which serve as ‘refugia’ for aquatic species and much of the channel is dry. We categorised these waterholes into ‘main waterholes’, which are located in the main part of the river channel and ‘satellite waterholes’, which are located in distributary river channels.2. We used mitochondrial sequences and allozymes to investigate levels of genetic diversity and patterns of connectivity among waterholes for two obligate freshwater species: Macrobrachium australiense (Decapoda: Palaemonidae) and Notopala sublineata (Gastropoda: Viviparidae).3. We sampled 31 waterholes for M. australiense and 12 for N. sublineata. Based on a 505‐bp fragment of cytochrome oxidase subunit I, we identified 54 haplotypes in a sample of 232 individuals for M. australiense and based on a 457‐bp fragment of the same gene, 36 haplotypes in a sample of 145 individuals for N. sublineata.4. Both nuclear and mitochondrial genetic data sets indicated that estimates of genetic diversity were not different in populations inhabiting main and satellite waterholes for either species. Also, there was generally very limited genetic differentiation among populations at any site.5. We suggest that levels of connectivity among populations inhabiting waterholes at most sites are higher than expected. High levels of connectivity may help to maintain overall high levels of genetic diversity as well as low levels of genetic differentiation among waterholes within sites.
Does nitrogen become limiting under high‐P conditions in detritus‐based tropical streams?
Authors: STALLCUP LINDSAY A. , ARDÓN MARCELO , PRINGLE CATHERINE M. 
Published: June 2006

Summary1. We examined effects of nutrients on leaf breakdown in interior forest streams at La Selva Biological Station, Costa Rica. We tested the hypothesis that dissolved inorganic nitrogen (DIN) becomes limiting when ambient phosphorus (P) concentration is high. We also compared the breakdown of relatively ‘low quality’ leaves (lower C : N, Trema integerrima) with that of ‘higher quality’ leaves (higher C : N, Ficus insipida) in a high‐P stream.2. Litterbags were incubated in two streams: one enriched experimentally with P [target concentration 200 μg soluble reactive phosphorus (SRP) L−1] and one control (naturally low P concentration approximately 10 μg SRP L−1). Ammonium enrichment was achieved by adding fertiliser upstream of half of the litterbags in each stream.3. Phosphorus addition stimulated leaf breakdown, microbial respiration, ergosterol and leaf %P. Leaf breakdown rate was consistent with those in La Selva streams with naturally high P concentration.4. Nitrogen (N) addition had no effect on leaf breakdown, microbial respiration, ergosterol or leaf chemistry in either the P‐enriched or the reference stream, in spite of low N : P ratios. We conclude that N is probably not limiting in streams at La Selva that are naturally high in P. This may be due to moderately high ambient N concentration (>200 μg DIN L−1) prevailing throughout the year.5. The species with a lower C : N decomposed more rapidly and supported higher microbial activity than that with a higher C : N. Subtle differences in leaf N content, as well as dissolved P concentration, may be important in determining microbial colonisation and subsequent leaf breakdown.
Microfibril‐associated Protein 4 Binds to Surfactant Protein A (SP‐A) and Colocalizes with SP‐A in the Extracellular Matrix of the Lung
Authors: Schlosser A. , Thomsen T. , Shipley J. M. , Hein P. W. , Brasch F. , Tornøe I. , Nielsen O. , Skjødt K. , Palaniyar N. , Steinhilber W. , McCormack F. X. , Holmskov U. 
Published: June 2006

AbstractPulmonary surfactant protein A (SP‐A) is an oligomeric collectin that recognizes lipid and carbohydrate moieties present on broad range of micro‐organisms, and mediates microbial lysis and clearance. SP‐A also modulates multiple immune‐related functions including cytokine production and chemotaxis for phagocytes. Here we describe the molecular interaction between the extracellular matrix protein microfibril‐associated protein 4 (MFAP4) and SP‐A. MFAP4 is a collagen‐binding molecule containing a C‐terminal fibrinogen‐like domain and a N‐terminal located integrin‐binding motif. We produced recombinant MFAP4 with a molecular mass of 36 and 66 kDa in the reduced and unreduced states respectively. Gel filtration chromatography and chemical crosslinking showed that MFAP4 forms oligomers of four dimers. We demonstrated calcium‐dependent binding between MFAP4 and human SP‐A1 and SP‐A2. No binding was seen to recombinant SP‐A composed of the neck region and carbohydrate recognition domain of SP‐A indicating that the interaction between MFAP4 and SP‐A is mediated via the collagen domain of SP‐A. Monoclonal antibodies directed against MFAP4 and SP‐A were used for immunohistochemical analysis, which demonstrates that the two molecules colocalize both on the elastic fibres in the interalveolar septum and in elastic lamina of pulmonary arteries of chronically inflamed lung tissue. We conclude, that MFAP4 interacts with SP‐A via the collagen region in vitro, and that MFAP4 and SP‐A colocates in different lung compartments indicating that the interaction may be operative in vivo.
Ex Vivo Responses for Interferon‐gamma and Proinflammatory Cytokine Secretion to Low‐Molecular‐Weight Antigen MTB12 of Mycobacterium tuberculosis during Human Tuberculosis
Authors: Lee J.‐S. , Son J. W. , Jung S.‐B. , Kwon Y.‐M. , Yang C.‐S. , Oh J.‐H. , Song C.‐H. , Kim H.‐J. , Park J.‐K. , Paik T.‐H. , Jo E.‐K. 
Published: June 2006

AbstractMTB12 protein, also called CFP‐2, is a major and early secreted component of Mycobacterium tuberculosis. However, its role during mycobacterial infection has been poorly characterized. In this study, we purified the native MTB12 protein and investigated the profile of MTB12‐induced cytokines [interferon (IFN)‐γ, tumour necrosis factor (TNF)‐α and interleukin (IL)‐6], in early tuberculosis (TB) patients (n = 20) and healthy controls (n = 35). The cytokine profiles were compared with those induced by the 30‐kDa antigen (Ag). In healthy controls, MTB12‐induced IFN‐γ production was markedly decreased in peripheral blood mononuclear cells compared with 30‐kDa Ag‐induced IFN‐γ. In TB patients, the mean IFN‐γ level induced by MTB12 was lower than that induced by the 30‐kDa Ag, albeit the difference was not significant. After 2 months of anti‐TB therapy, both the MTB12‐ and 30‐kDa‐induced IFN‐γ levels were significantly increased in TB patients. MTB12‐induced TNF‐α and IL‐6 levels were prominently upregulated in monocyte‐derived macrophages from TB patients, but they were not significantly different from those induced by the 30‐kDa Ag. Further, the activation of p38 mitogen‐activated protein kinase and extracellular signal‐regulated kinase was required for the induction of TNF‐α and IL‐6 by MTB12, as well as by the 30‐kDa Ag. Collectively, these data suggest that the MTB12 protein plays an essential role for proinflammatory responses through the MAPK pathway during the early stages of human TB, even though its T‐cell immunoreactivity is weaker than that of the 30‐kDa Ag.
Dynamic T‐lymphocyte Chemokine Receptor Expression Induced by Interferon‐beta Therapy in Multiple Sclerosis
Authors: Krakauer M. , Sorensen P. S. , Khademi M. , Olsson T. , Sellebjerg F. 
Published: June 2006

AbstractTreatment with interferon (IFN)‐β reduces clinical disease activity in multiple sclerosis (MS). Using flow cytometry, an enzyme‐linked immunosorbent assay and a real‐time polymerase chain reaction, we studied in vivo IFN‐β‐induced effects on CD4+ T‐lymphocyte chemokine receptor expression as these influence central nervous system (CNS) transmigration and inflammation. At ‘steady state’ (≥1 day after the most recent IFN‐β injection), IFN‐β treatment increased CD4+ T‐cell surface expression of CC chemokine receptor (CCR)4, CCR5 and CCR7 after 3 months of treatment, whereas that of CXC chemokine receptor (CXCR)3 was unaltered. Conversely, at 9–12 h after the most recent IFN‐β injection, CCR4, CCR5 and CCR7 expressions were unaltered, while CXCR3 expression was reduced. CD4+ T‐cell surface expression of CCR4 was significantly lower in untreated MS patients compared with healthy volunteers. Of the plasma chemokines, only CXCL10 was increased by IFN‐β treatment; CCL3, CCL4, CCL5 and CXCL9 were unaltered. CCR5 mRNA expression in blood mononuclear cells correlated with the expression of T‐helper type 1 (Th1)‐associated genes whereas CCR4 and CCR7 mRNA expression correlated with Th2 and immunoregulatory genes. In conclusion, IFN‐β treatment caused ‘steady‐state’ increases of several chemokine receptors relevant for CD4+ T‐lymphocyte trafficking and function, possibly facilitating lymphocyte migration into the CNS. An important therapeutic effect of IFN‐β treatment may be the normalization of a decreased Th2‐related CD4+ T‐cell CCR4 expression in MS patients. Surface chemokine receptor expression and CXCL10 varied according to the timing of blood sampling in relation to the most recent IFN‐β injection. Thus, it is imperative to distinguish acute effects of IFN‐β from steady‐state effects.
IgA receptors in health and disease
Authors: Wines Bruce D. , Hogarth P. Mark 
Published: June 2006

AbstractThe varied interaction of the Fc region of IgA with receptors confers this antibody class with many of its unique properties. The epithelial polymeric Ig receptor on mucosal epithelial cells transports polymeric immunoglobulin A (pIgA) produced by mucosal B cells to the mucosal surface where, in complex with the secretory component (SC), this secretory immunoglobulin A (SIgA) excludes the multitude of dietary, environmental, and microbial antigens that continuously bombard the mucosae. In health, this IgA‐mediated exclusion not only forms the initial defence against infection, it also spares the systemic immune system from potentially deleterious responses to innocuous antigens which can otherwise culminate in inflammatory bowel disease or asthma. Beyond antigen exclusion, in closer encounters with antigens, IgA receptors play roles in protective immunity and disease. FcaRI is the principal myeloid IgA receptor and is responsible for differing IgA‐mediated effector responses such as respiratory burst, degranulation, and phagocytosis variously by granulyoctes, monocytes, and macrophages. Furthermore an unknown IgA receptor specific for the secretory component (SC) elicits powerful effector responses from eosinophils. On dendritic cells, FcaRI participates in antigen presentation while on microfold cells, key cells in mucosal antigen presentation, another unknown IgA receptor functions in the transport of antigens across the mucosal epithelial barrier. The activity of another uncharacterized IgA1/IgD receptor on T cells may affect autoimmune disorders. The interplay of different IgA receptors affects immune complex deposition in the common renal disease immunoglobulin A nephropathy (IgAN). Finally, the therapeutic application of various IgA receptors has been sought in the areas of infectious disease, vaccines, and cancer.
Characterization of single crystal silicon and electroplated nickel films by uniaxial tensile test with in situ X‐ray diffraction measurement
Authors: NAMAZU T. , INOUE S. 
Published: June 2006

ABSTRACTIn this study, mechanical properties of micron‐thick single crystalline silicon (Si) and electroplated nickel (Ni) films at intermediate temperatures are investigated by means of X‐ray diffraction (XRD) tensile testing. The developed tensile test technique enables us to directly measure lateral (out‐of‐plane) elastic strain of microscale crystalline specimen using XRD during tensile loading, and determines Young's modulus, Poisson's ratio and tensile strength of the Si and Ni specimens. The specimens, measuring 10 μm thick, 300 μm wide and 3 mm long, are prepared through a conventional micro‐machining process, and the ultraviolet lithographie galvanoformung abformung (UV‐LIGA) process including a molding and an electroplating. The Si specimens, showing brittle fracture at room temperature (R.T.), have average Young's modulus and Poisson's ratio of 169 GPa and 0.35, respectively, in very good agreement with analytical values. The Ni specimens, showing ductile fracture, have those of 190 GPa and 0.24, lower than bulk coarse grained Ni. Young's moduli of both the Si and Ni specimens decrease with increasing temperature, but Poisson's ratios are independent of temperature. The influence of specimen size on elastic‐plastic properties of the specimens is discussed.
Audio–vocal interaction in the pontine brainstem during self‐initiated vocalization in the squirrel monkey
Authors: Hage Steffen R. , Jürgens Uwe , Ehret Günter 
Published: June 2006

AbstractThe adjustment of the voice by auditory input happens at several brain levels. The caudal pontine brainstem, though rarely investigated, is one candidate area for such audio–vocal integration. We recorded neuronal activity in this area in awake, behaving squirrel monkeys (Saimiri sciureus) during vocal communication, using telemetric single‐unit recording techniques. We found audio–vocal neurons at locations not described before, namely in the periolivary region of the superior olivary complex and the adjacent pontine reticular formation. They showed various responses to external sounds (noise bursts) and activity increases (excitation) or decreases (inhibition) to self‐produced vocalizations, starting prior to vocal onset and continuing through vocalizations. In most of them, the responses to noise bursts and self‐produced vocalizations were similar, with the only difference that neuronal activity started prior to vocal onset. About one‐third responded phasically to noise bursts, independent of whether they increased or decreased their activity to vocalization. The activity of most audio–vocal neurons correlated with basic acoustic features of the vocalization, such as call duration and/or syllable structure. Auditory neurons near audio–vocal neurons showed significantly more frequent phasic response patterns than those in areas without audio–vocal activity. Based on these findings, we propose that audio–vocal neurons showing similar activity to external acoustical stimuli and vocalization play a role in olivocochlear regulation. Specifically, audio–vocal neurons with a phasic response to external auditory stimuli are candidates for the mediation of basal audio–vocal reflexes such as the Lombard reflex. Thus, our findings suggest that complex audio–vocal integration mechanisms exist in the ventrolateral pontine brainstem.