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Search Results: 1 - 10 of 201998 matches for " Joseph G. Brand "
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Phylogenetic Analysis and Taste Cell Expression of Calpain 9 in Catfish (Ictalurus punctatus)  [PDF]
Tetsuya Ookura, Eiki Koyama, Anne Hansen, John H. Teeter, Yukio Kawamura, Joseph G. Brand
Natural Science (NS) , 2015, DOI: 10.4236/ns.2015.73016
Abstract: The calpains, calcium-activated neutral proteases, play important roles in calcium-regulated intra-cellular signal transduction cascades. Here we report the isolation and initial characterization of a cDNA encoding a calpain 9, digestive tract specific calpain, from catfish taste epithelium. This calpain 9 (Ip-CAPN9a) shares 61% identity with human calpain 9. Phylogenetic analysis provides evidence that catfish calpain 9 and the related enzymes from Oncorhynchus mykiss, Danio rerio, Xenopus laevis, Mus musculus, Rattus norvegicus and Homo sapiens make up a distinct clade within the tissue-specific calpain family. Northern blot analysis reveals that Ip-CAPN9a is predominantly expressed in barbell and digestive tract, but not expressed in brain. An antibody against the N-terminal segment of Ip-CAPN9a recognizes cells within the taste buds in catfish barbells.
Biochemical enrichment and biophysical characterization of a taste receptor for L-arginine from the catfish, Ictalurus puntatus
William Grosvenor, Yuri Kaulin, Andrew I Spielman, Douglas L Bayley, D Lynn Kalinoski, John H Teeter, Joseph G Brand
BMC Neuroscience , 2004, DOI: 10.1186/1471-2202-5-25
Abstract: Both PHA-E and RCA-I almost exclusively labeled an 82–84 kDa protein band of an SDS-PAGE of solubilized barbel taste epithelial membranes. Further, both rhodamine-conjugated RCA-I and polyclonal antibodies raised to the 82–84 kDa electroeluted peptides labeled the apical region of catfish taste buds. Because of the specificity shown by RCA-I, lectin affinity was chosen as the first of a three-step procedure designed to enrich the presumed LGICR for L-Arg. Purified and CHAPS-solubilized taste epithelial membrane proteins were subjected successively to (1), lectin (RCA-I) affinity; (2), gel filtration (Sephacryl S-300HR); and (3), ion exchange chromatography. All fractions from each chromatography step were evaluated for L-Arg-induced ion channel activity by reconstituting each fraction into a lipid bilayer. Active fractions demonstrated L-Arg-induced channel activity that was inhibited by D-arginine (D-Arg) with kinetics nearly identical to those reported earlier for L-Arg-stimulated ion channels of native barbel membranes reconstituted into lipid bilayers. After the final enrichment step, SDS-PAGE of the active ion channel protein fraction revealed a single band at 82–84 kDa which may be interpreted as a component of a multimeric receptor/channel complex.The data are consistent with the supposition that the L-Arg receptor is a LGICR. This taste receptor remains active during biochemical enrichment procedures. This is the first report of enrichment of an active LGICR from the taste system of vertebrata.The initial event in taste transduction involves recognition of taste stimuli by plasma membrane-associated receptor proteins. These proteins are concentrated at the apical end of specialized neuro-epithelial cells (taste cells) found within multicellular end-organs known as taste buds [1,2]. The recognition binding sites for most taste stimuli face the exterior environment. The interaction of a taste stimulus with this recognition site triggers a chain of metabolic an
Sour Ageusia in Two Individuals Implicates Ion Channels of the ASIC and PKD Families in Human Sour Taste Perception at the Anterior Tongue
Taufiqul Huque, Beverly J. Cowart, Luba Dankulich-Nagrudny, Edmund A. Pribitkin, Douglas L. Bayley, Andrew I. Spielman, Roy S. Feldman, Scott A. Mackler, Joseph G. Brand
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0007347
Abstract: Background The perception of sour taste in humans is incompletely understood at the receptor cell level. We report here on two patients with an acquired sour ageusia. Each patient was unresponsive to sour stimuli, but both showed normal responses to bitter, sweet, and salty stimuli. Methods and Findings Lingual fungiform papillae, containing taste cells, were obtained by biopsy from the two patients, and from three sour-normal individuals, and analyzed by RT-PCR. The following transcripts were undetectable in the patients, even after 50 cycles of amplification, but readily detectable in the sour-normal subjects: acid sensing ion channels (ASICs) 1a, 1β, 2a, 2b, and 3; and polycystic kidney disease (PKD) channels PKD1L3 and PKD2L1. Patients and sour-normals expressed the taste-related phospholipase C-β2, the δ-subunit of epithelial sodium channel (ENaC) and the bitter receptor T2R14, as well as β-actin. Genomic analysis of one patient, using buccal tissue, did not show absence of the genes for ASIC1a and PKD2L1. Immunohistochemistry of fungiform papillae from sour-normal subjects revealed labeling of taste bud cells by antibodies to ASICs 1a and 1β, PKD2L1, phospholipase C-β2, and δ-ENaC. An antibody to PKD1L3 labeled tissue outside taste bud cells. Conclusions These data suggest a role for ASICs and PKDs in human sour perception. This is the first report of sour ageusia in humans, and the very existence of such individuals (“natural knockouts”) suggests a cell lineage for sour that is independent of the other taste modalities.
The S100A10 Subunit of the Annexin A2 Heterotetramer Facilitates L2-Mediated Human Papillomavirus Infection
Andrew W. Woodham, Diane M. Da Silva, Joseph G. Skeate, Adam B. Raff, Mark R. Ambroso, Heike E. Brand, J. Mario Isas, Ralf Langen, W. Martin Kast
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0043519
Abstract: Mucosotropic, high-risk human papillomaviruses (HPV) are sexually transmitted viruses that are causally associated with the development of cervical cancer. The most common high-risk genotype, HPV16, is an obligatory intracellular virus that must gain entry into host epithelial cells and deliver its double stranded DNA to the nucleus. HPV capsid proteins play a vital role in these steps. Despite the critical nature of these capsid protein-host cell interactions, the precise cellular components necessary for HPV16 infection of epithelial cells remains unknown. Several neutralizing epitopes have been identified for the HPV16 L2 minor capsid protein that can inhibit infection after initial attachment of the virus to the cell surface, which suggests an L2-specific secondary receptor or cofactor is required for infection, but so far no specific L2-receptor has been identified. Here, we demonstrate that the annexin A2 heterotetramer (A2t) contributes to HPV16 infection and co-immunoprecipitates with HPV16 particles on the surface of epithelial cells in an L2-dependent manner. Inhibiting A2t with an endogenous annexin A2 ligand, secretory leukocyte protease inhibitor (SLPI), or with an annexin A2 antibody significantly reduces HPV16 infection. With electron paramagnetic resonance, we demonstrate that a previously identified neutralizing epitope of L2 (aa 108–120) specifically interacts with the S100A10 subunit of A2t. Additionally, mutation of this L2 region significantly reduces binding to A2t and HPV16 pseudovirus infection. Furthermore, downregulation of A2t with shRNA significantly decreases capsid internalization and infection by HPV16. Taken together, these findings indicate that A2t contributes to HPV16 internalization and infection of epithelial cells and this interaction is dependent on the presence of the L2 minor capsid protein.
The Bamboo-Eating Giant Panda (Ailuropoda melanoleuca) Has a Sweet Tooth: Behavioral and Molecular Responses to Compounds That Taste Sweet to Humans
Peihua Jiang, Jesusa Josue-Almqvist, Xuelin Jin, Xia Li, Joseph G. Brand, Robert F. Margolskee, Danielle R. Reed, Gary K. Beauchamp
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0093043
Abstract: A growing body of behavioral and genetic information indicates that taste perception and food sources are highly coordinated across many animal species. For example, sweet taste perception is thought to serve to detect and motivate consumption of simple sugars in plants that provide calories. Supporting this is the observation that most plant-eating mammals examined exhibit functional sweet perception, whereas many obligate carnivores have independently lost function of their sweet taste receptors and exhibit no avidity for simple sugars that humans describe as tasting sweet. As part of a larger effort to compare taste structure/function among species, we examined both the behavioral and the molecular nature of sweet taste in a plant-eating animal that does not consume plants with abundant simple sugars, the giant panda (Ailuropoda melanoleuca). We evaluated two competing hypotheses: as plant-eating mammals, they should have a well-developed sweet taste system; however, as animals that do not normally consume plants with simple sugars, they may have lost sweet taste function, as has occurred in strict carnivores. In behavioral tests, giant pandas avidly consumed most natural sugars and some but not all artificial sweeteners. Cell-based assays revealed similar patterns of sweet receptor responses toward many of the sweeteners. Using mixed pairs of human and giant panda sweet taste receptor units (hT1R2+gpT1R3 and gpT1R2+hT1R3) we identified regions of the sweet receptor that may account for behavioral differences in giant pandas versus humans toward various sugars and artificial sweeteners. Thus, despite the fact that the giant panda's main food, bamboo, is very low in simple sugars, the species has a marked preference for several compounds that taste sweet to humans. We consider possible explanations for retained sweet perception in this species, including the potential extra-oral functions of sweet taste receptors that may be required for animals that consume plants.
Deconstructing the Breakthrough Leadership Thinking of Visionary Social Change Agents
—Insights and Strategies for Leading Transformative Change from Four Case Studies
 [PDF]

Joseph G. Claudet
Advances in Applied Sociology (AASoci) , 2016, DOI: 10.4236/aasoci.2016.69023
Abstract: This article reports results of a multiple case investigation of the breakthrough leadership thinking processes of visionary social change agent leaders. Case study profiles of four selected social change leaders who have made lasting career contributions as innovative change agents in their chosen professional domains are presented. In-depth analyses of the four change leader cases revealed new conceptual understandings regarding fundamental connections among each individual leader’s core values and beliefs, breakthrough leadership thinking processes, and the ways in which each leader was able to leverage innovative insights generated from this breakthrough thinking to inspire and guide positive transformative change in the leader’s chosen domain and socio-organizational setting. Seven key change leadership insights and strategies derived from the study’s collective individual and comparative case analyses are highlighted that may be of practical use to change leaders working today in a variety of professional domains and socio-organizational settings.
Surveying the Expanding Cyberscape of New and Evolving Digital Learning Technologies
—A Review of Recent Advances in Three Creative Focus Areas of Digital Learning Design and Development Impacting the Field of Education
 [PDF]

Joseph G. Claudet
Creative Education (CE) , 2017, DOI: 10.4236/ce.2017.810110
Abstract: This article presents an overview and review of recent advances in digital teaching and learning technologies—advances that collectively represent an emergent period of breakthrough “digital innovation” leadership in the field of education. These digital education technologies are creating new career learning and advancement opportunities for people around the world through expanding and enhancing their access to globally connected learning. Three specific “creative focus areas” of digital learning design and development are identified for review. The article includes a discussion of salient features and design thrusts of major research, development, and practical application activities currently being conducted within each creative focus area. Some of the most innovative learning programs being developed by researchers, designers, and education leaders engaged within each of these creative focus areas are highlighted, along with an assessment of the impact of these programs on educational practice.
The effect of technology on learner attention and achievement in the classroom
G Bester,L Brand
South African Journal of Education , 2013,
Abstract: The objective of this investigation was to determine the effect of technology on attention and achievement within a classroom context, taking motivation and concentration into account as well. Lessons in Geography, English and Mathematics were presented to an experimental and a control group consisting of 23 and 22 Grade 8 learners, respectively. Technology was implemented for the experimental group but not for the control group. Significant differences were found between the average achievements of a group of learners, exposed to technology during a lesson, compared to a group not exposed to technology. Significant differences were also found between the average attention of a group of learners, exposed to technology during a lesson, compared to a group not exposed to technology. A high positive relationship was obtained between motivation and concentration and moderate to high positive correlations were obtained between attention, concentration and motivation, taken jointly as independent variables and achievement as the dependent variable.
Pseudogenization of a Sweet-Receptor Gene Accounts for Cats' Indifference toward Sugar
Xia Li,Weihua Li,Hong Wang,Jie Cao,Kenji Maehashi,Liquan Huang,Alexander A Bachmanov,Danielle R Reed,Véronique Legrand-Defretin,Gary K Beauchamp,Joseph G Brand
PLOS Genetics , 2005, DOI: 10.1371/journal.pgen.0010003
Abstract: Although domestic cats (Felis silvestris catus) possess an otherwise functional sense of taste, they, unlike most mammals, do not prefer and may be unable to detect the sweetness of sugars. One possible explanation for this behavior is that cats lack the sensory system to taste sugars and therefore are indifferent to them. Drawing on work in mice, demonstrating that alleles of sweet-receptor genes predict low sugar intake, we examined the possibility that genes involved in the initial transduction of sweet perception might account for the indifference to sweet-tasting foods by cats. We characterized the sweet-receptor genes of domestic cats as well as those of other members of the Felidae family of obligate carnivores, tiger and cheetah. Because the mammalian sweet-taste receptor is formed by the dimerization of two proteins (T1R2 and T1R3; gene symbols Tas1r2 and Tas1r3), we identified and sequenced both genes in the cat by screening a feline genomic BAC library and by performing PCR with degenerate primers on cat genomic DNA. Gene expression was assessed by RT-PCR of taste tissue, in situ hybridization, and immunohistochemistry. The cat Tas1r3 gene shows high sequence similarity with functional Tas1r3 genes of other species. Message from Tas1r3 was detected by RT-PCR of taste tissue. In situ hybridization and immunohistochemical studies demonstrate that Tas1r3 is expressed, as expected, in taste buds. However, the cat Tas1r2 gene shows a 247-base pair microdeletion in exon 3 and stop codons in exons 4 and 6. There was no evidence of detectable mRNA from cat Tas1r2 by RT-PCR or in situ hybridization, and no evidence of protein expression by immunohistochemistry. Tas1r2 in tiger and cheetah and in six healthy adult domestic cats all show the similar deletion and stop codons. We conclude that cat Tas1r3 is an apparently functional and expressed receptor but that cat Tas1r2 is an unexpressed pseudogene. A functional sweet-taste receptor heteromer cannot form, and thus the cat lacks the receptor likely necessary for detection of sweet stimuli. This molecular change was very likely an important event in the evolution of the cat's carnivorous behavior.
?''Globalización sostenible''? Desarrollo sostenible como pegamento para el montón de cristales trizados del neoliberalismo
Brand, Ulrich;G?rg, Christoph;
Ambiente & Sociedade , 2003, DOI: 10.1590/S1414-753X2003000200004
Abstract: during the world summit on sustainable development, held in johannesburg by mid 2001, it was clearly observed that our understandings and practices concerning sustainable development are on a dead end. this is due to the fact that the much more dynamic processes of neo-liberal globalization and of world restructuring had been ignored, including the new legitimacy of wars in the '90s. after september 11th, 2001, it was evident that we live in a non-hegemonic context with particular consequences. nevertheless, ?sustainable development'' did not emerge as a counter-discourse. on the contrary, its directions and practices were more and more compatible with dominant rebuilding processes. sustainable development lost its critical impact through its focus on cooperation and western modern knowledge, its technocratic concept of politics, the prevailing of environmental issues over the ones of development and nation-state as privileged areas for implementation of policies. in addition, international sustainable development organizations (in the article the biological diversity convention is given as an example) takes part in nature's economic exploitation process. finally, in a recent past, actions aiming at establishing military structure in southern cone countries _ justified by the necessity of sustainable development policies _ gained legitimacy. currently, the ?rio process'' tries to reconcile globalization processes to sustainable development and, eventually, the concept of ?sustainable globalization'' will emerge as a new paradigm for dominant trends and practices. at last, the authors argue that the most dynamic challenges to neo-liberal globalization and militarization arise in a different political background which is, until now, hardly linked to sustainable development policies: the so called movements of globalization criticism. from a theoretical perspective, the article reports on the regulation theory and critical theory of the state, as well as on concepts of
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