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Multiple Bands (multiple + bands)
Selected AbstractsLow-density caveolae-like membrane from Xenopus laevis oocytes is enriched in RasJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2001Susan E. SadlerArticle first published online: 10 JUL 200 Abstract Detergent-free discontinuous sucrose density gradient centrifugation was used to resolve low- and high-density membrane fractions from Xenopus laevis oocytes. Compared to high-density membrane, low-density oocyte membrane is enriched two-fold in cholesterol and highly enriched in ganglioside GM1. Protein immunoblotting of membrane fractions from whole cells with polyclonal anti-human caveolin antibody detected multiple bands, including a distinctive triad with apparent molecular weights of 21, 33, and 48 kDa. To more clearly determine which of these caveolin-like protein(s) is associated with the oocyte plasma membrane, microdissection was used to separate external membrane (cortical preparations containing plasma membrane) from intracellular membrane. Cortical membrane preparations displayed a single 21-kDa caveolin-like protein in low-density membrane. Internal oocyte membrane displayed the higher molecular weight bands of 33 and 48 kDa and a lesser amount of the 21-kDa protein in low-density membrane fractions. Monoclonal anti-human Ras antibody detected a single 23-kDa immunoblot band that is enriched an average of eight-fold in low-density membrane fractions prepared from whole cells. This is the first report of caveolin-associated, low-density membrane in amphibian oocytes, and is consistent with a role for caveolin and caveolae-like microdomains in oocyte signal transduction. © 2001 Wiley-Liss, Inc. [source] Immunoglobulin-E Reactivity to a Glycosylated Food Allergen (Peanuts) Due to Interference With Cross-Reactive Carbohydrate Determinants in Heavy DrinkersALCOHOLISM, Issue 8 2009C. Vidal Background:, N-glycans in plant and invertebrate glycoproteins can induce extensive IgE cross-reactivity therefore limiting the specificity of in vitro allergy tests. IgE sensitization to N-glycans (cross-reactive carbohydrate determinants, CCDs) may be increased in heavy drinkers, who therefore show IgE reactivity to aeroallergens, latex, and Hymenoptera venoms. The peanut, a CCD-bearing allergen, is the leading cause of severe food allergic reactions in many populations. Aim of the study:, To investigate the potential interference of CCDs with determinations of IgE to peanuts in heavy drinkers. Methods:, We determined IgE to peanuts and IgE to a CCD marker (MUXF3, the N-glycan from bromelain) in 41 heavy drinkers admitted to the hospital and 54 healthy controls. None of the participants reported symptoms of peanut allergy. In cases with positive (,0.35 kU/l) IgE to peanuts, we performed inhibition assays with a neoglycoprotein consisting of MUXF3 molecules coupled to bovine serum albumin (MUXF3 -BSA) and a similar neoglycoprotein lacking xylose and fucose (MM-BSA). In the same cases, we screened for IgE to a panel of recombinant nonglycosylated peanut allergens. SDS-PAGE immunoblotting and inhibition assays were performed in selected cases. Results:, The prevalence of positive IgE to peanuts was 22 and 3.7% in heavy drinkers and healthy controls, respectively (p < 0.001). Peanut-IgE positivity was closely related to the presence of IgE to CCDs. In most (8/9) heavy drinkers with positive IgE to peanuts, reactivity was inhibited by preincubation with MUXF3 -BSA, but not with MM-BSA. IgE binding to multiple bands on immunoblotting studies was also inhibited by MUXF3 -BSA preincubation. IgE to nonglycosylated recombinant peanut allergens was uniformly negative. Conclusion:, Heavy drinking is associated with clinically asymptomatic IgE reactivity to peanuts, a relevant food allergen, in relation to CCD interference. [source] A Raman spectroscopic study of the uranyl carbonate rutherfordineJOURNAL OF RAMAN SPECTROSCOPY, Issue 11 2007Ray L. Frost Abstract The molecular structure of the uranyl mineral rutherfordine has been investigated by the measurement of its Raman spectra at 298 and 77 K and complemented with infrared spectra. The infrared spectra of the (CO3)2, units in the anti-symmetric stretching region show complexity with three sets of carbonate bands observed. This, combined with the observation of multiple bands in the (CO3)2, bending region in both Raman and IR spectra, suggests that both monodentate and bidentate (CO3)2, units are present in the structure in accordance with the X-ray crystallographic studies. Complexity is also observed in the IR spectra of (UO2)2+ anti-symmetric stretching region and is attributed to non-identical UO bonds. Both Raman and infrared spectra of the rutherfordine show the presence of both water and hydroxyl units in the structure, as evidenced by IR bands at 3562 and 3465 cm,1 (OH) and 3343, 3185 and 2980 cm,1 (H2O). Raman spectra show the presence of four sharp bands at 3511, 3460, 3329 and 3151 cm,1. Copyright © 2007 John Wiley & Sons, Ltd. [source] Raman and IR spectral studies of D -phenylglycinium perchlorateJOURNAL OF RAMAN SPECTROSCOPY, Issue 9 2002S. Ramaswamy The Raman and infrared spectra of D -phenylglycinium perchlorate were recorded at room temperature. Tentative vibrational assignments of the observed wavenumbers were made by comparison with the vibrational wavenumbers of glycine, phenylalanine and other similar compounds. Anions were found to coordinate through hydrogen bonding interactions to other ligands in the crystal, affecting the Td symmetry and thereby causing the degeneracies of several modes to be removed. The extensive intermolecular hydrogen bonding in the crystal leads to a shift of bands due to the stretching and bending modes of various functional groups. The broadening and appearance of multiple bands for the carbonyl stretching mode due to the resonance interaction is also discussed. Copyright © 2002 John Wiley & Sons, Ltd. [source] A planar dual-meander-line antenna for multiband mobile handsetsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2006Hai-Ming Hsiao Abstract A planar dual-meander-line antenna consisting of three branch strips for a low-profile GSM/DCS/PCS/WLAN multiband mobile handset is proposed. The branch strips are designed to operate as quarter-wavelength structures at 900 and 2000 MHz, respectively, and the obtained impedance bandwidths are 120 MHz (about 13.2%) and 924 MHz (about 44.4%) for covering the required bandwidths of the GSM (890,960 MHz) and DCS/PCS/UMTS/WLAN (1710,1880/1850,1990/1920,2170/2400,2484 MHz) bands. The proposed antenna can be mounted on top of a mobile phone with a low profile of 20 mm from ground plane. The measured antenna radiation patterns are approximately omnidirectional across the multiresonant bands. Peak antenna gains for operating frequencies across the GSM/DCS/PCS/UMTS/WLAN multiple bands are measured to be 1.8 and 2.9 dBi, respectively, with gain variations within 0.5 dBi. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 883,888, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21507 [source] Secondary initiation of multiple bands of cumulonimbus over southern Britain.THE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 617 2006I: An observational case-study Abstract Special observing facilities have been assembled in southern England as part of the Convective Storm Initiation Project (CSIP) to study the mesoscale and convective-scale processes that determine precisely where warm-season convective showers will break out. This paper reports the results of a case-study during the pilot field campaign of CSIP in July 2004. One purpose of the pilot project was to demonstrate the value of various observational facilities and to evaluate the usefulness of a variety of analysis and synthesis techniques. Amongst other things, the case-study demonstrates the utility of high-resolution imagery from the Meteosat Second Generation satellite for tracking the early stages of the convective clouds, and of a new clear-air scanning radar at Chilbolton for mapping both the top of the boundary layer and the initial growth of the convective cells that penetrate it. The particular event studied involved the triggering of convection that developed into three parallel arcs of showers and thunderstorms. The first arc was triggered along the leading edge of the outflow (density current) from an earlier cluster of showers, but the convection in the second and third arcs was triggered by a different mechanism. The paper describes in detail the way in which this convection broke through the stable layer, or lid, at the top of a boundary layer of variable depth. The strength of the lid decreased and the depth of the boundary layer increased with time as a result of diurnal heating, but the precise locations where convection finally broke through were determined by the spatial variability in boundary-layer depth. The analysis suggests that a wave-like modulation of the boundary-layer depth of amplitude 150 m, perhaps due to a gravity-wave disturbance from the earlier cluster of showers, had a greater influence on where the convection was triggered than the modest hills (typically 200 m high) in southern England. © Royal Meteorological Society, 2006. Contributions by P. A. Clark and M. E. B. Gray are Crown Copyright. [source] Cloud-resolving model simulations of multiply-banded frontal cloudsTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 611 2005M. Pizzamei Abstract An idealized two-dimensional cloud-resolving model is used to investigate the formation and temporal evolution of multiply-banded clouds in frontal zones. Radar observations often show both upright and slantwise convection in the circulations associated with such bands. The aim is to examine the interaction between upright and slantwise convection and to determine the mechanisms leading to multiple banding. A warm bubble is used to initiate convection in the frontal zone, which has an initial thermodynamic profile based on observations. Further triggering occurs and banded clouds evolve. The initially upright plumes become tilted due to the so-called ,M adjustment process (upscale development). Observed multiple bands in frontal zones are frequently attributed to the release of conditional symmetric instability (CSI). However, in these simulations, there is no evidence of the release of CSI despite the fragmentation of slantwise bands into multiple layers in the mid-troposphere. Successive triggering of upright convection is instead associated with a spreading cold pool driven by evaporative cooling in the slanted downdraughts. Triggering can occur on both the warm- and cold-air sides of the frontal zone, and is sensitive to the microphysical parametrization used. Copyright © 2005 Royal Meteorological Society. [source] Neutrophil gelatinase,associated lipocalin is expressed in osteoarthritis and forms a complex with matrix metalloproteinase 9ARTHRITIS & RHEUMATISM, Issue 10 2007Kalpana Gupta Objective Expression of matrix metalloproteinase 9 (MMP-9) is up-regulated in osteoarthritis (OA) and usually presents as multiple bands when synovial fluid (SF) from OA patients is analyzed by zymography. Among these bands is an ,125,130,kd band for high molecular weight (HMW) gelatinase, which has not been characterized. This study was undertaken to characterize the HMW MMP activity in OA SF. Methods MMP activity in OA SF was determined by gelatin zymography. Recombinant MMPs were used to identify MMP activity on the zymogram. Western immunoblotting, immunoprecipitation, and immunodepletion analyses were performed using antibodies specific for human MMP-9 and human neutrophil gelatinase,associated lipocalin (NGAL). Human cartilage matrix degradation was determined by dimethylmethylene blue assay. Results Zymographic analysis showed that the HMW gelatinase in OA SF comigrated with a purified NGAL,MMP-9 complex. Results of Western immunoblotting showed that the HMW gelatinase was also recognized by antibodies specific for human NGAL or human MMP-9. These same antibodies also immunoprecipitated the HMW gelatinase activity from OA SF. The NGAL,MMP-9 complex was reconstituted in vitro in gelatinase buffer. In the presence of NGAL, MMP-9 activity was stabilized; in the absence of NGAL, rapid loss of MMP-9 activity occurred. MMP-9,mediated release of cartilage matrix proteoglycans was significantly higher in the presence of NGAL (P < 0.05). Conclusion Our findings demonstrate that the HMW gelatinase activity in OA SF represents a complex of NGAL and MMP-9. The ability of NGAL to protect MMP-9 activity is relevant to cartilage matrix degradation in OA and may represent an important mechanism by which NGAL may contribute to the loss of cartilage matrix proteins in OA. [source] Collar-induced elevation of mRNA and functional activity of 5-HT1B receptor in the rabbit carotid arteryBRITISH JOURNAL OF PHARMACOLOGY, Issue 8 2000Inge S Geerts Hypersensitivity to serotonin (5-HT) develops in rabbit collared carotid arteries. Previous data demonstrated the involvement of 5-HT1 -like receptors which are not active in normal carotid arteries. This study investigated the interaction in the rabbit carotid artery between 5-HT and a moderate tone as this can uncover functional 5-HT1 -like receptors. Furthermore, the expression of messenger RNA (mRNA) and protein of 5-HT1B, 5-HT1D and 5-HT2A receptors was addressed. Silicone collars were placed around the carotid arteries of male New Zealand White rabbits for 1 week. Rings from inside (=collar) and outside (=sham) the collar were either mounted in isolated organ baths for isometric force measurements or frozen in liquid nitrogen to isolate total RNA or proteins which were subsequently analysed by respectively reverse transcriptase-polymerase chain reaction and Western blot analysis. In sham and collared rings concentration-response curves (CRC's) to 5-HT were monophasic. Only in collared segments the presence of a 5-HT2A antagonist (spiperone or ketanserin, 0.1 ,M) revealed a biphasic CRC which was even more pronounced when a moderate tone was induced by KCl pointing to functional 5-HT1 -like receptors. The rabbit carotid artery constitutively expressed 5-HT1B and 5-HT2A mRNA, not 5-HT1D mRNA. Manipulation of the carotid artery increased the 5-HT1B mRNA level. Collar placement raised it even further. The 5-HT2A mRNA level remained unchanged. All the anti-5-HT receptor antibodies tested resulted in variable, non specific patterns with multiple bands. In conclusion, collar placement elevates mRNA expression and activity of the 5-HT1B receptor in the rabbit carotid artery. British Journal of Pharmacology (2000) 131, 1723,1731; doi:10.1038/sj.bjp.0703732 [source] Role of Environmental Factors on the Structure and Spectroscopic Response of 5,-DNA,Porphyrin Conjugates Caused by Changes in the Porphyrin,Porphyrin InteractionsCHEMISTRY - A EUROPEAN JOURNAL, Issue 44 2009Angela Mammana Dr. Abstract We have explored the utility, strength, and limitation of through-space exciton-coupled circular dichroism in determination of the secondary structure of optically active chromophoric nanoarrays using the example of end-capped porphyrin, and metalloporphyrin,oligodeoxynucleotide conjugates. We put special emphasis on the explanation of the origin and significance of the distinctive multiple bands in the CD spectra (trisignate and tetrasignate CD bands). Such CD profiles are often observed in chiral aggregates or multichromophoric arrays but have never before been studied in detail. We found that variation of temperature and ionic strength has a profound effect on the geometry of the porphyrin,DNA conjugates and thus the nature of electronic interactions. At lower temperatures and in the absence of NaCl all three 5,-DNA,porphyrin conjugates display negative bisignate CD exciton couplets of variable intensity in the Soret region resulting from through-space interaction between the electric transition dipole moments of the two end-capped porphyrins. As the temperature is raised these exciton couplets are transformed into single positive bands originating from the porphyrin,single-strand DNA interactions. At higher ionic strengths and low temperatures, multisignate CD bands are observed in the porphyrin Soret region. These CD signature bands originate from a combination of intermolecular, end-to-end porphyrin,porphyrin stacking between duplexes and porphyrin,DNA interactions. The intermolecular aggregation was confirmed by fluorescence and absorption spectroscopy and resonance light scattering. DeVoe theoretical CD calculations, in conjunction with molecular dynamics simulations and Monte Carlo conformational searches, were used to mimic the observed bisignate exciton-coupled CD spectra as well as multiple CD bands. Calculations correctly predicted the sign and shape of the experimentally observed CD spectra. These studies reveal that the exciton-coupled circular dichroism is a very useful technique for the determination of the structure of optically active arrays. [source] | |||||||||||||