oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2020 ( 4 )

2019 ( 398 )

2018 ( 521 )

2017 ( 538 )

Custom range...

Search Results: 1 - 10 of 326047 matches for " Carolyn S. S. Hudak "
All listed articles are free for downloading (OA Articles)
Page 1 /326047
Display every page Item
Acute Overactive Endocannabinoid Signaling Induces Glucose Intolerance, Hepatic Steatosis, and Novel Cannabinoid Receptor 1 Responsive Genes
Maxwell A. Ruby, Daniel K. Nomura, Carolyn S. S. Hudak, Anne Barber, John E. Casida, Ronald M. Krauss
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0026415
Abstract: Endocannabinoids regulate energy balance and lipid metabolism by stimulating the cannabinoid receptor type 1 (CB1). Genetic deletion and pharmacological antagonism have shown that CB1 signaling is necessary for the development of obesity and related metabolic disturbances. However, the sufficiency of endogenously produced endocannabinoids to cause hepatic lipid accumulation and insulin resistance, independent of food intake, has not been demonstrated. Here, we show that a single administration of isopropyl dodecylfluorophosphonate (IDFP), perhaps the most potent pharmacological inhibitor of endocannabinoid degradation, increases hepatic triglycerides (TG) and induces insulin resistance in mice. These effects involve increased CB1 signaling, as they are mitigated by pre-administration of a CB1 antagonist (AM251) and in CB1 knockout mice. Despite the strong physiological effects of CB1 on hepatic lipid and glucose metabolism, little is known about the downstream targets responsible for these effects. To elucidate transcriptional targets of CB1 signaling, we performed microarrays on hepatic RNA isolated from DMSO (control), IDFP and AM251/IDFP-treated mice. The gene for the secreted glycoprotein lipocalin 2 (lcn2), which has been implicated in obesity and insulin resistance, was among those most responsive to alterations in CB1 signaling. The expression pattern of IDFP mice segregated from DMSO mice in hierarchal cluster analysis and AM251 pre-administration reduced (>50%) the majority (303 of 533) of the IDFP induced alterations. Pathway analysis revealed that IDFP altered expression of genes involved in lipid, fatty acid and steroid metabolism, the acute phase response, and amino acid metabolism in a CB1-dependent manner. PCR confirmed array results of key target genes in multiple independent experiments. Overall, we show that acute IDFP treatment induces hepatic TG accumulation and insulin resistance, at least in part through the CB1 receptor, and identify novel cannabinoid responsive genes.
Isospectral deformations of metrics on spheres
Carolyn S. Gordon
Mathematics , 2000, DOI: 10.1007/s002220100150
Abstract: We construct non-trivial continuous isospectral deformations of Riemannian metrics on the ball and on the sphere in $\R^n$ for every $n\geq 9$. The metrics on the sphere can be chosen arbitrarily close to the round metric; in particular, they can be chosen to be positively curved. The metrics on the ball are both Dirichlet and Neumann isospectral and can be chosen arbitrarily close to the flat metric.
Isospectral potentials and conformally equivalent isospectral metrics on spheres, balls and Lie groups
Carolyn S. Gordon,Dorothee Schueth
Mathematics , 2002,
Abstract: We construct pairs of conformally equivalent isospectral Riemannian metrics $\phi_1 g$ and $\phi_2 g$ on spheres $S^n$ and balls $B^{n+1}$ for certain dimensions $n$, the smallest of which is $n=7$, and on certain compact simple Lie groups. In the case of Lie groups, the metric $g$ is left-invariant. In the case of spheres and balls, the metric $g$ is not the standard metric but may be chosen arbitrarily close to the standard one. For the same manifolds $(M,g)$ we also show that the functions $\phi_1$ and $\phi_2$ are isospectral potentials for the Schr\"odinger operator $\hbar^2\Delta +\phi$. To our knowledge, these are the first examples of isospectral potentials and of isospectral conformally equivalent metrics on simply connected closed manifolds.
Discrete Return Lidar in Natural Resources: Recommendations for Project Planning, Data Processing, and Deliverables
Jeffrey S. Evans,Andrew T. Hudak,Russ Faux,Alistair M. S. Smith
Remote Sensing , 2009, DOI: 10.3390/rs1040776
Abstract: Recent years have seen the progression of light detection and ranging (lidar) from the realm of research to operational use in natural resource management. Numerous government agencies, private industries, and public/private stakeholder consortiums are planning or have recently acquired large-scale acquisitions, and a national U.S. lidar acquisition is likely before 2020. Before it is feasible for land managers to integrate lidar into decision making, resource assessment, or monitoring across the gambit of natural resource applications, consistent standards in project planning, data processing, and user-driven products are required. This paper introduces principal lidar acquisition parameters, and makes recommendations for project planning, processing, and product standards to better serve natural resource managers across multiple disciplines.
Field Studies Reveal Strong Postmating Isolation between Ecologically Divergent Butterfly Populations
Carolyn S. McBride,Michael C. Singer
PLOS Biology , 2012, DOI: 10.1371/journal.pbio.1000529
Abstract: Gene flow between populations that are adapting to distinct environments may be restricted if hybrids inherit maladaptive, intermediate phenotypes. This phenomenon, called extrinsic postzygotic isolation (EPI), is thought to play a critical role in the early stages of speciation. However, despite its intuitive appeal, we know surprisingly little about the strength and prevalence of EPI in nature, and even less about the specific phenotypes that tend to cause problems for hybrids. In this study, we searched for EPI among allopatric populations of the butterfly Euphydryas editha that have specialized on alternative host plants. These populations recall a situation thought typical of the very early stages of speciation. They lack consistent host-associated genetic differentiation at random nuclear loci and show no signs of reproductive incompatibility in the laboratory. However, they do differ consistently in diverse host-related traits. For each of these traits, we first asked whether hybrids between populations that use different hosts (different-host hybrids) were intermediate to parental populations and to hybrids between populations that use the same host (same-host hybrids). We then conducted field experiments to estimate the effects of intermediacy on fitness in nature. Our results revealed strong EPI under field conditions. Different-host hybrids exhibited an array of intermediate traits that were significantly maladaptive, including four behaviors. Intermediate foraging height slowed the growth of larvae, while intermediate oviposition preference, oviposition site height, and clutch size severely reduced the growth and survival of the offspring of adult females. We used our empirical data to construct a fitness surface on which different-host hybrids can be seen to fall in an adaptive valley between two peaks occupied by same-host hybrids. These findings demonstrate how ecological selection against hybrids can create a strong barrier to gene flow at the early stages of adaptive divergence.
Ethnic differential item functioning in the assessment of quality of life in cancer patients
Ian S Pagano, Carolyn C Gotay
Health and Quality of Life Outcomes , 2005, DOI: 10.1186/1477-7525-3-60
Abstract: Item response theory methods were used to assess differential item functioning (DIF) in the quality of life (measured by the EORTC QLQ-C30) of cancer patients across four ethnic groups (Caucasian, Filipino, Hawaiian, and Japanese). The sample consisted of 359 cancer patients.Results showed the presence of DIF on several items, indicating ethnic differences in the assessment of quality of life. Relative to the Caucasian and Japanese groups, items related to physical functioning, cognitive functioning, social functioning, nausea and vomiting, and financial difficulties exhibited DIF for Filipinos. On these items Filipinos exhibited either higher or lower QoL scores, even though their overall QoL was the same.This evidence may explain why Filipinos have previously been found to have lower overall QoL. Although Filipinos score lower on QoL than other groups, this may not reflect lower QoL, but rather differences in how QoL is defined. The presence of DIF did not appear, however, to alter the psychometric properties of the QLQ-C30.In recent years medical researchers have shown increasing interest in the physical, psychological, and social health of individuals suffering from disease and treatment-related toxicity [1-3]. These broad characteristics are generally grouped under the inclusive heading quality of life (QoL), and offer a contrast to the more traditional biomedical markers, such as survival time or disease remission. A general definition of QoL is patients' perspectives on their ability to live useful and fulfilling lives, as influenced by, but not completely dependent on disease and treatment [1]. As an instrument of measurement in the clinical setting, QoL is defined functionally by patients' own perceptions of their performance in physical, occupational, psychological, social, financial, and somatic (i.e., physical symptomatology) areas [4,5].The QoL construct is an important one with respect to measuring disease progress and treatment effectiveness. Because
Assessment of Survivor Concerns (ASC): A newly proposed brief questionnaire
Carolyn C Gotay, Ian S Pagano
Health and Quality of Life Outcomes , 2007, DOI: 10.1186/1477-7525-5-15
Abstract: We developed and tested a six-item instrument, the Assessment of Survivor Concerns (ASC). Construct validity was examined in a multiple group confirmatory factor analysis (CFA) with 592 short-term and 161 long-term cancer survivors. Convergent and discriminant validity was examined through comparisons with the PANAS (Positive and Negative Affect Schedule) and the CES-D (Center for Epidemiologic Studies Depression) measures.CFA models for the ASC with short- and long-term survivors showed good fit, with equivalent structure across both groups of cancer survivors. Convergent and discriminant validity was also supported through analyses of the PANAS and CES-D. One item (children's health worry) did not perform as well as the others, so the models were re-run with the item excluded, and the overall fit was improved.The ASC showed excellent internal consistency and validity. We recommend the revised five-item instrument as an appropriate measure for assessment of cancer survivor worries.As treatments and detection for cancer improve, life expectancy for cancer survivors is longer than it has ever been before. While this is of course a welcome development, there are potential concerns that need to be addressed. One of these is the constant fear experienced by many cancer survivors that their cancer will return. While the risk of recurrence varies considerably depending on the cancer type, tumor characteristics, and stage at diagnosis, many cancers do return, generally in the first few years following diagnosis, but sometimes even after many years of remission. Fear of cancer recurrence is recognized as having significant negative psychological consequences, and researchers have recently taken a greater interest in the construct. Lee-Jones et al. provided an important review of the work that had been done in this area up to 1997 [1].Northouse reported the first work on the development of a scale specific for measuring fear of cancer recurrence, the 22-item Northouse Fear o
The enigmatic eosinophil: investigation of the biological role of eosinophils in parasitic helmint infection
Ovington, Karen S;Behm, Carolyn A;
Memórias do Instituto Oswaldo Cruz , 1997, DOI: 10.1590/S0074-02761997000800013
Abstract: in many helminth infected hosts the number of eosinophils increases dramatically, often without any concurrent increases in the number of other leukocytes, so that eosinophils become the dominant cell type. many experimental investigations have shown that the eosinophilia is induced by interleukin-5 (il-5) but its functional significance remains unclear. mice genetically deficient in il-5 (il-5-/-) have been used to evaluate the functional consequences of the il-5 dependent eosinophilia in helminth infected hosts. host pathology and level of infection were determined in il-5-/- and wild type mice infected with a range of species representative of each major group of helminths. the effects of il-5 deficiency were very heterogeneous. of the six species of helminth examined, il-5 dependent immune responses had no detectable effect in infections with three species, namely the cestodes mesocestoides corti and hymenolepis diminuta and the trematode fasciola hepatica. in contrast, il-5 dependent immune responses were functionally important in mice infected with three species, notably all nematodes. damage to the lungs caused by migrating larvae of toxocara canis was reduced in il-5-/- mice. infections of the intestine by adult stages of either strongyloides ratti or heligmosomoides polygyrus were more severe in il-5-/- mice. adult intestinal nematodes were clearly deleteriously affected by il-5 dependent processes since in its presence there were fewer worms which had reduced fecundity and longevity. the implications of these results for the viability of using inhibitors of il-5 as a therapy for asthma are considered.
The enigmatic eosinophil: investigation of the biological role of eosinophils in parasitic helmint infection
Ovington Karen S,Behm Carolyn A
Memórias do Instituto Oswaldo Cruz , 1997,
Abstract: In many helminth infected hosts the number of eosinophils increases dramatically, often without any concurrent increases in the number of other leukocytes, so that eosinophils become the dominant cell type. Many experimental investigations have shown that the eosinophilia is induced by interleukin-5 (IL-5) but its functional significance remains unclear. Mice genetically deficient in IL-5 (IL-5-/-) have been used to evaluate the functional consequences of the IL-5 dependent eosinophilia in helminth infected hosts. Host pathology and level of infection were determined in IL-5-/- and wild type mice infected with a range of species representative of each major group of helminths. The effects of IL-5 deficiency were very heterogeneous. Of the six species of helminth examined, IL-5 dependent immune responses had no detectable effect in infections with three species, namely the cestodes Mesocestoides corti and Hymenolepis diminuta and the trematode Fasciola hepatica. In contrast, IL-5 dependent immune responses were functionally important in mice infected with three species, notably all nematodes. Damage to the lungs caused by migrating larvae of Toxocara canis was reduced in IL-5-/- mice. Infections of the intestine by adult stages of either Strongyloides ratti or Heligmosomoides polygyrus were more severe in IL-5-/- mice. Adult intestinal nematodes were clearly deleteriously affected by IL-5 dependent processes since in its presence there were fewer worms which had reduced fecundity and longevity. The implications of these results for the viability of using inhibitors of IL-5 as a therapy for asthma are considered.
Determinación y caracterización botánica de hábitats mapuche del sector Zewko-Rüpükura, comuna de Nueva Imperial (IX Región, Chile)
Carolyn Sánchez,Enrique Hauenstein,Luis Peralta
Cultura-Hombre-Sociedad , 2004, DOI: 10.7770/cuhso-v8n1-art202
Abstract: Se determinaron los hábitats mapuche presentes en la comunidad indígena Zewko del sector Rüpükura, comuna de Nueva Imperial, IX Región, Chile, y se caracterizaron botánicamente los más reconocidos. Se les analizó desde el punto de vista mapuche y occidental, aplicando paralelamente metodologías participativas y botánicas. Se identificaron 23 ecosistemas, de los cuales 8 fueron mencionados como los más relevantes; de éstos, el menoko (38%), el malli (19%) y el trayen (13%) son los que presentaron los más altos porcentajes de importancia. Vegetacionalmente se caracterizaron dos comunidades vegetales nativas, la pradera húmeda de junquillo (Juncetum procerii), correspondiente al malli , y el bosque pantanoso de temo y pitra (Blepharocalyo-Myrceugenietum exsuccae), que corresponde al menoko. Con respecto a la flora vascular se identificaron 91 especies en el sector, de las cuales el 72% correspondió a especies nativas. La forma de vida mayormente representada fueron los hemicriptófitos con un 40%. Al analizar los dos ámbitos de la investigación se reconoció la diferente concepción existente entre los sistemas de caracterización mapuche V/S el sistema ecológico occidental convencional, por lo que se hace esencial considerar estas diferencias a la hora de investigar acerca de los recursos naturales.
Page 1 /326047
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.