Publications by authors named "Siegelman M"

Music-evoked autobiographical memories (MEAMs) are typically elicited by music that listeners have heard before. While studies that have directly manipulated music familiarity show that familiar music evokes more MEAMs than music listeners have not heard before, music that is unfamiliar to the listener can also sporadically cue autobiographical memory. Here we examined whether music that sounds familiar even without previous exposure can produce spontaneous MEAMs.

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Human language is expressive because it is compositional: The meaning of a sentence (semantics) can be inferred from its structure (syntax). It is commonly believed that language syntax and semantics are processed by distinct brain regions. Here, we revisit this claim using precision fMRI methods to capture separation or overlap of function in the brains of individual participants.

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American Samoa is experiencing rapid relative sea level rise due to increases in global sea level and significant post-2009 earthquake land subsidence, endangering homes and critical infrastructure. Wave and water-level observations collected over a fringing reef at Faga'itua Bay, American Samoa, in 2017 reveal depth-limited shoreline sea-swell wave heights over the range of conditions sampled. Using field data to calibrate a one-dimensional, phase-resolving nonhydrostatic wave model (SWASH), we examine the influence of water level on wave heights over the reef for a range of current and future sea levels.

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Making meaningful inferences about the functional architecture of the language system requires the ability to refer to the same neural units across individuals and studies. Traditional brain imaging approaches align and average brains together in a common space. However, lateral frontal and temporal cortex, where the language system resides, is characterized by high structural and functional inter-individual variability.

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Familiar music facilitates memory retrieval in adults with dementia. However, mechanisms behind this effect, and its generality, are unclear because of a lack of parallel work in healthy aging. Exposure to familiar music enhances spontaneous recall of memories directly cued by the music, but it is unknown whether such effects extend to deliberate recall more generally - e.

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Two analytic traditions characterize fMRI language research. One relies on averaging activations across individuals. This approach has limitations: because of inter-individual variability in the locations of language areas, any given voxel/vertex in a common brain space is part of the language network in some individuals but in others, may belong to a distinct network.

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To understand what you are reading now, your mind retrieves the meanings of words and constructions from a linguistic knowledge store (lexico-semantic processing) and identifies the relationships among them to construct a complex meaning (syntactic or combinatorial processing). Do these two sets of processes rely on distinct, specialized mechanisms or, rather, share a common pool of resources? Linguistic theorizing, empirical evidence from language acquisition and processing, and computational modeling have jointly painted a picture whereby lexico-semantic and syntactic processing are deeply inter-connected and perhaps not separable. In contrast, many current proposals of the neural architecture of language continue to endorse a view whereby certain brain regions selectively support syntactic/combinatorial processing, although the locus of such "syntactic hub", and its nature, vary across proposals.

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Aside from the language-selective left-lateralized frontotemporal network, language comprehension sometimes recruits a domain-general bilateral frontoparietal network implicated in executive functions: the multiple demand (MD) network. However, the nature of the MD network's contributions to language comprehension remains debated. To illuminate the role of this network in language processing in humans, we conducted a large-scale fMRI investigation using data from 30 diverse word and sentence comprehension experiments (481 unique participants [female and male], 678 scanning sessions).

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The frontotemporal language network responds robustly and selectively to sentences. But the features of linguistic input that drive this response and the computations that these language areas support remain debated. Two key features of sentences are typically confounded in natural linguistic input: words in sentences (a) are semantically and syntactically combinable into phrase- and clause-level meanings, and (b) occur in an order licensed by the language's grammar.

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Is sentence structure processed by the same neural and cognitive resources that are recruited for processing word meanings, or do structure and meaning rely on distinct resources? Linguistic theorizing and much behavioral evidence suggest tight integration between lexico-semantic and syntactic representations and processing. However, most current proposals of the neural architecture of language continue to postulate a distinction between the two. One of the earlier and most cited pieces of neuroimaging evidence in favor of this dissociation comes from a paper by Dapretto and Bookheimer (1999).

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L-selectin has been suggested to play a role in the pathogenesis of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. Here we demonstrate that L-selectin(-/-) SJL mice are susceptible to proteolipid protein (PLP)-induced EAE because the compromised antigen-specific T cell proliferation in peripheral lymph nodes is fully compensated by the T cell response raised in their spleen. Transfer of PLP-specific T cells into syngeneic recipients induced EAE independent of the presence or absence of L-selectin on PLP-specific T cells or in the recipient.

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Background: The epidermal growth factor receptor (EGFR) gene is the prototype member of the type I receptor tyrosine kinase (TK) family and plays a pivotal role in cell proliferation and differentiation. There are three well described polymorphisms that are associated with increased protein production in experimental systems: a polymorphic dinucleotide repeat (CA simple sequence repeat 1 [CA-SSR1]) in intron one (lower number of repeats) and two single nucleotide polymorphisms (SNPs) in the promoter region, -216 (G/T or T/T) and -191 (C/A or A/A). The objective of this study was to examine distributions of these three polymorphisms and their relationships to each other and to EGFR gene mutations and allelic imbalance (AI) in non-small cell lung cancers.

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CD4CD25(+) regulatory T cells are fundamental to the maintenance of peripheral tolerance and have great therapeutic potential. However, efforts in this regard have been hampered by limiting cell numbers in vivo, an anergic phenotype in vitro, and a rudimentary understanding of the molecular basis for the functional state of CD4CD25(+) regulatory T cells (Treg cells). Here we show heterogeneity of suppressor activity among activated CD4CD25(+) Treg cells and that, within this population, the functionally active, hyaluronan-binding form of CD44 (CD44(act)) is strikingly correlated with superior suppressor activity.

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CD44 on activated T cells can initiate contact and mediate rolling on hyaluronan on endothelial cells. We have shown that the integrin VLA-4 is used preferentially over LFA-1 in conjunction with this rolling interaction for firm adhesion. Here, we show by coimmunoprecipitation and transfection studies that CD44 associates with VLA-4 but not LFA-1 on the plasma membrane of immune cells.

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Nicolosi and Byrd in 2002 summarized empirical research on birth order and sexual orientation in men, which research has documented that homosexual men have a later birth order than heterosexual men. They did not, however, note a more refined analysis of an earlier null finding by Siegelman. This 1998 reanalysis by Blanchard, Zucker, Siegelman, Dickey, and Klassen also confirmed the later birth order of homosexual men.

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CD44 on lymphocytes binding to its carbohydrate ligand hyaluronan can mediate primary adhesion (rolling interactions) of lymphocytes on vascular endothelial cells. This adhesion pathway is utilized in the extravasation of activated T cells from the blood into sites of inflammation and therefore influences patterns of lymphocyte homing and inflammation. Hyaluronan is a glycosaminoglycan found in the extracellular matrix and is involved in a number of biological processes.

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Leukocytes extravasate from the blood in response to physiologic or pathologic demands by means of complementary ligand interactions between leukocytes and endothelial cells. The multistep model of leukocyte extravasation involves an initial transient interaction ("rolling" adhesion), followed by secondary (firm) adhesion. We recently showed that binding of CD44 on activated T lymphocytes to endothelial hyaluronan (HA) mediates a primary adhesive interaction under shear stress, permitting extravasation at sites of inflammation.

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Galpha15 activates phospholipase Cbeta in response to the greatest variety of agonist-stimulated heptahelical receptors among the four Gq class G-protein alpha subunits expressed in mammals. Galpha15 is primarily expressed in hematopoietic cells in fetal and adult mice. We disrupted the Galpha15 gene by homologous recombination in embryonic stem cells to identify its biological functions.

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Adhesive interactions between receptors on vascular endothelial cells (EC) and circulating leukocytes are pivotal in regulating leukocyte extravasation. Although primary adhesion of lymphocytes to EC has been primarily attributed to the selectin family of receptors, CD44 can also mediate this function when activated to bind its ligand hyaluronan (HA). Triggering through the T cell receptor induces activated CD44 and CD44-dependent primary adhesion in both human and mouse lymphocytes, and the interaction can mediate the extravasation of activated T cells into an inflamed site.

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T cell recruitment to extralymphoid tissues is fundamental to the initiation and perpetuation of the inflammatory state during immune and autoimmune responses. Interleukin (IL)-15 is a proinflammatory cytokine whose described functions largely overlap with those of IL-2. The latter is attributable in large part to its binding of the heterotrimeric receptor that contains the beta and gamma chains of the IL-2R in combination with an unique IL-15R alpha chain.

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Adhesion molecules borne by both endothelial cells and circulating leukocytes are in large measure responsible for guiding the process of extravasation. The selectin family has been primarily associated with the early stages of adhesion involving initial contact and rolling. A significant body of evidence has accumulated indicating a fundamental role for the endothelial members of this family, E- and P-selectin, in a variety of inflammatory states and models.

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Homosexual men have a higher mean birth order than do heterosexual men, primarily because they have a greater number of older brothers. The purpose of this study was to determine whether the same difference occurs in homosexual vs heterosexual women. The probands were 964 homosexual and heterosexual, male and female volunteers, from whom birth order data were collected with self-administered questionnaires.

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Interactions between complementary receptors on leukocytes and endothelial cells play a central role in regulating extravasation from the blood and thereby affect both normal and pathologic inflammatory responses. CD44 on lymphocytes that has been "activated" to bind its principal ligand hyaluronate (HA) on endothelium can mediate the primary adhesion (rolling) of lymphocytes to vascular endothelial cells under conditions of physiologic shear stress, and this interaction is used for activated T cell extravasation into an inflamed site in vivo in mice (DeGrendele, H.C.

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