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971.
Carlson CS Heagerty PJ Nord AS Pritchard DK Ranchalis J Boguch JM Duan H Hatsukami TS Schwartz SM Rieder MJ Nickerson DA Jarvik GP 《Human genetics》2007,121(1):65-75
Inflammatory markers have consistently been associated with vascular disease. Evidence of genetic polymorphisms in inflammatory
loci that predict severe carotid artery disease (CAAD) would suggest that this relationship is not secondary to other correlated
factors, but related to inflammation itself. We examined the full common genetic variation in 42 inflammatory loci for prediction
of severe CAAD versus ultrasound proven controls using a tagSNP approach. For selected loci, monocyte RNA levels were contrasted
in subjects with and without CAAD. We confirm the association of IL6−174, FGB
−455, and ALOX5 with CAAD and show that multiple ALOX5 SNPs independently predict CAAD. We provide evidence for previously unreported associations of SNPs in IL4R, NFKBIA, and PLG with CAAD, and weaker evidence for associations with CSF3, IL10RA, and VCAM1. The NFKBIA and IL10RA expression levels significantly differed between subjects with CAAD and controls. These results support a role for genetic
variation related to inflammation in CAAD and a causal role for specific gene products.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
972.
Colgan OC Ferguson G Collins NT Murphy RP Meade G Cahill PA Cummins PM 《American journal of physiology. Heart and circulatory physiology》2007,292(6):H3190-H3197
Blood-brain barrier (BBB) controls paracellular solute diffusion into the brain microenvironment and is maintained primarily by tight junctions between adjacent microvascular endothelial cells. Studies implicate blood flow-associated shear stress as a pathophysiological mediator of BBB function, although detailed biochemical data are scarce. We hypothesize that shear stress upregulates BBB function via direct modulation of expression and properties of pivotal tight-junction proteins occludin and zonula occludens-1 (ZO-1). Bovine brain microvascular endothelial cells (BBMvECs) were exposed to either steady or pulsatile shear stress (10 and 14 dyn/cm(2), respectively) for 24 h. Sheared BBMvECs were monitored for occludin-ZO-1 expression, association, and subcellular localization, and transendothelial permeability of BBMvECs to FITC-dextran and (14)[C]sucrose was assessed. Actin reorganization and BBMvEC realignment were observed following steady shear stress for 24 h. Substantial increases in occludin mRNA and protein expression (2.73 +/- 0.26- and 1.83 +/- 0.03-fold) and in occludin-ZO-1 association (2.12 +/- 0.15-fold) were also observed. Steady shear stress also induced clear relocalization of both proteins to the cell-cell border in parallel with reduced transendothelial permeability to FITC-dextran (but not sucrose). Following pulsatile shear stress, increased protein levels for both occludin and ZO-1 (2.15 +/- 0.02- and 1.67 +/- 0.21-fold) and increased occludin-ZO-1 association (2.91 +/- 0.14-fold) were observed in parallel with a reduction in transendothelial permeability to (14)[C]sucrose. Shear stress upregulates BBMvEC barrier function at the molecular level via modulation of expression, association, and localization of occludin and ZO-1. The pulsatile shear model appeared to give the most profound biochemical responses. 相似文献
973.
Bahassi el M Penner CG Robbins SB Tichy E Feliciano E Yin M Liang L Deng L Tischfield JA Stambrook PJ 《Mutation research》2007,616(1-2):201-209
Allelic variants of CHEK2 contribute to an elevated risk for human breast cancer and possibly other cancer types. In particular, the CHEK2*1100delC polymorphic variant has been identified as a low-penetrance breast cancer susceptibility allele in breast cancer families with wild type BRCA1 and BRCA2. To better understand the molecular basis by which this allele increases risk for disease, we have generated a mouse in which the wild type CHEK2 (Chk2 in mouse) allele has been replaced with the 1100delC variant. Mouse embryo fibroblasts (MEFs) derived from these mice have an altered cell cycle profile in which a far greater proportion of cells are in S-phase and in G2 (4N) compared with wild type cells. The mutant cells show signs of spontaneous genomic instability as indicated by polyploidy and an increase in DNA double strand breaks. 相似文献
974.
Does human proximity affect antibody prevalence in marine-foraging river otters (Lontra canadensis)?
Gaydos JK Conrad PA Gilardi KV Blundell GM Ben-David M 《Journal of wildlife diseases》2007,43(1):116-123
The investigation of diseases of free-ranging river otters (Lontra canadensis) is a primary conservation priority for this species; however, very little is known about diseases of river otters that forage in marine environments. To identify and better understand pathogens that could be important to marine-foraging river otters, other wildlife species, domestic animals, and humans and to determine if proximity to human population could be a factor in disease exposure, serum samples from 55 free-ranging marine-foraging river otters were tested for antibodies to selected pathogens. Thirty-five animals were captured in Prince William Sound, Alaska (USA), an area of low human density, and 20 were captured in the San Juan Islands, Washington State (USA), an area characterized by higher human density. Of 40 river otters tested by indirect immunofluorescent antibody test, 17.5% were seropositive (titer > or =320) for Toxoplasma gondii. All positive animals came from Washington. Of 35 river otters tested for antibodies to Leptospira interrogans using the microscopic agglutination test, 10 of 20 (50%) from Washington were seropositive (titer > or =200). None of the 15 tested animals from Alaska were positive. Antibodies to Neospora caninum (n=40), Sarcocystis neurona (n=40), Brucella abortus (n=55), avian influenza (n=40), canine distemper virus (n=55), phocine distemper virus (n=55), dolphin morbillivirus (n=55), porpoise morbillivirus (n=55), and Aleutian disease parvovirus (n=46) were not detected. Identifying exposure to T. gondii and L. interrogans in otters from Washington State but not in otters from Alaska suggests that living proximal to higher human density and its associated agricultural activities, domestic animals, and rodent populations could enhance river otter exposure to these pathogens. 相似文献
975.
Rising atmospheric CO2 concentration is a key driver of enhanced global greening, thought to account for up to 70% of increased global vegetation in recent decades. CO2 fertilization effects have further profound implications for ecosystems, food security and biosphere‐atmosphere feedbacks. However, it is also possible that current trends will not continue, due to ecosystem level constraints and as plants acclimate to future CO2 concentrations. Future predictions of plant response to rising [CO2] are often validated using single‐generation short‐term FACE (Free Air CO2 Enrichment) experiments but whether this accurately represents vegetation response over decades is unclear. The role of transgenerational plasticity and adaptation in the multigenerational response has yet to be elucidated. Here, we propose that naturally occurring high CO2 springs provide a proxy to quantify the multigenerational and long‐term impacts of rising [CO2] in herbaceous and woody species respectively, such that plasticity, transgenerational effects and genetic adaptation can be quantified together in these systems. In this first meta‐analysis of responses to elevated [CO2] at natural CO2 springs, we show that the magnitude and direction of change in eight of nine functional plant traits are consistent between spring and FACE experiments. We found increased photosynthesis (49.8% in spring experiments, comparable to 32.1% in FACE experiments) and leaf starch (58.6% spring, 84.3% FACE), decreased stomatal conductance (gs, 27.2% spring, 21.1% FACE), leaf nitrogen content (6.3% spring, 13.3% FACE) and Specific Leaf Area (SLA, 9.7% spring, 6.0% FACE). These findings not only validate the use of these sites for studying multigenerational plant response to elevated [CO2], but additionally suggest that long‐term positive photosynthetic response to rising [CO2] are likely to continue as predicted by single‐generation exposure FACE experiments. 相似文献
976.
Hong-Ping Guan Xiaodong Yang Ku Lu Sheng-Ping Wang Jose M. Castro-Perez Stephen Previs Michael Wright Vinit Shah Kithsiri Herath Dan Xie Daphne Szeto Gail Forrest Jing Chen Xiao Oksana Palyha Li-Ping Sun Paula J. Andryuk Samuel S. Engel Yusheng Xiong Songnian Lin David E. Kelley Mark D. Erion Harry R. Davis Liangsu Wang 《Journal of lipid research》2015,56(11):2183-2195
Glucagon and insulin have opposing action in governing glucose homeostasis. In type 2 diabetes mellitus (T2DM), plasma glucagon is characteristically elevated, contributing to increased gluconeogenesis and hyperglycemia. Therefore, glucagon receptor (GCGR) antagonism has been proposed as a pharmacologic approach to treat T2DM. In support of this concept, a potent small-molecule GCGR antagonist (GRA), MK-0893, demonstrated dose-dependent efficacy to reduce hyperglycemia, with an HbA1c reduction of 1.5% at the 80 mg dose for 12 weeks in T2DM. However, GRA treatment was associated with dose-dependent elevation of plasma LDL-cholesterol (LDL-c). The current studies investigated the cause for increased LDL-c. We report findings that link MK-0893 with increased glucagon-like peptide 2 and cholesterol absorption. There was not, however, a GRA-related modulation of cholesterol synthesis. These findings were replicated using structurally diverse GRAs. To examine potential pharmacologic mitigation, coadministration of ezetimibe (a potent inhibitor of cholesterol absorption) in mice abrogated the GRA-associated increase of LDL-c. Although the molecular mechanism is unknown, our results provide a novel finding by which glucagon and, hence, GCGR antagonism govern cholesterol metabolism. 相似文献
977.
Focus: Addiction: Reducing Fatal Opioid Overdose: Prevention,Treatment and Harm Reduction Strategies
Kathryn F. Hawk Federico E. Vaca Gail D’Onofrio 《The Yale journal of biology and medicine》2015,88(3):235-245
The opioid overdose epidemic is a major threat to the public’s health, resulting in the development and implementation of a variety of strategies to reduce fatal overdose [1-3]. Many strategies are focused on primary prevention and increased access to effective treatment, although the past decade has seen an exponential increase in harm reduction initiatives. To maximize identification of opportunities for intervention, initiatives focusing on prevention, access to effective treatment, and harm reduction are examined independently, although considerable overlap exists. Particular attention is given to harm reduction approaches, as increased public and political will have facilitated widespread implementation of several initiatives, including increased distribution of naloxone and policy changes designed to increase bystander assistance during a witnessed overdose [4-7]. 相似文献
978.
Jennie?E. Murray Mirjam van?der?Burg Hanna IJspeert Paula Carroll Qian Wu Takashi Ochi Andrea Leitch Edward?S. Miller Boris Kysela Alireza Jawad Armand Bottani Francesco Brancati Marco Cappa Valerie Cormier-Daire Charu Deshpande Eissa?A. Faqeih Gail?E. Graham Emmanuelle Ranza Tom?L. Blundell Andrew?P. Jackson Grant?S. Stewart Louise?S. Bicknell 《American journal of human genetics》2015,96(3):412-424
Non-homologous end joining (NHEJ) is a key cellular process ensuring genome integrity. Mutations in several components of the NHEJ pathway have been identified, often associated with severe combined immunodeficiency (SCID), consistent with the requirement for NHEJ during V(D)J recombination to ensure diversity of the adaptive immune system. In contrast, we have recently found that biallelic mutations in LIG4 are a common cause of microcephalic primordial dwarfism (MPD), a phenotype characterized by prenatal-onset extreme global growth failure. Here we provide definitive molecular genetic evidence supported by biochemical, cellular, and immunological data for mutations in XRCC4, encoding the obligate binding partner of LIG4, causing MPD. We report the identification of biallelic mutations in XRCC4 in five families. Biochemical and cellular studies demonstrate that these alterations substantially decrease XRCC4 protein levels leading to reduced cellular ligase IV activity. Consequently, NHEJ-dependent repair of ionizing-radiation-induced DNA double-strand breaks is compromised in XRCC4 cells. Similarly, immunoglobulin junctional diversification is impaired in cells. However, immunoglobulin levels are normal, and individuals lack overt signs of immunodeficiency. Additionally, in contrast to individuals with LIG4 mutations, pancytopenia leading to bone marrow failure has not been observed. Hence, alterations that alter different NHEJ proteins give rise to a phenotypic spectrum, from SCID to extreme growth failure, with deficiencies in certain key components of this repair pathway predominantly exhibiting growth deficits, reflecting differential developmental requirements for NHEJ proteins to support growth and immune maturation. 相似文献
979.
Carole Di Poi Shannon Atkinson Anne Hoover‐Miller Gail Blundell 《Marine Mammal Science》2015,31(3):1098-1117
We examined the effects of maternal buffering in free‐ranging Pacific harbor seal pups during capture and handling research procedures. We predicted that pups held with their mother would benefit from social buffering and exhibit lower cortisol concentrations resulting from capture and handling than dependent pups caught without their mothers and weaned pups. We expected that pups captured with their mother that experienced a short separation would exhibit increased stress‐induced vocal behavior and activity level compared to dependent weaned pups caught alone. The results showed that the presence of the mother significantly buffered the stress response, as measured by reduced serum cortisol concentrations, in pups captured with their mothers as compared to dependent pups captured alone. Cortisol concentrations of mothers with pups initially were higher than nonlactating females, then diminished. Pups showed a significantly higher rate of vocalization soon after maternal separation compared to single pups separated for a longer period of time. Newly separated pups, especially males, showed a high level of activity compared to the other pups. The results provide unique quantitative evidence of the physiology underlying the maternal‐pup bond in a marine mammal, and the role that maternal buffering may play on the stress response of the offspring. 相似文献
980.
Xiaowei Yang Jingjing Zhu Chun-Yu Tung Gail Gardiner Qun Wang Hua-Chen Chang Baohua Zhou 《PloS one》2015,10(2)
Lunasin is a naturally occurring peptide isolated from soybeans and has been explored in cancer treatment. Lunasin inhibits NF-κB activation and thus pro-inflammatory cytokine and mediator production in macrophages. In this study we demonstrate that lunasin can effectively suppress allergic airway inflammation in two murine models of asthma. In an OVA+Alum sensitization model, intranasal lunasin treatment at the time of OVA challenges significantly reduced total cells counts in bronchoalveolar lavage (BAL) fluid and eosinophilia, peribronchiolar inflammatory infiltration, goblet cell metaplasia and airway IL-4 production. In an OVA+LPS intranasal sensitization model, lunasin treatment either at the time of sensitization or challenge has similar effects in suppress allergic airway inflammation including significantly reduced total cell and eosinophil counts in BAL fluid, inflammatory gene Fizz1 expression in the lung, and IL-4 production by OVA re-stimulated cells from mediastinal lymph nodes. We further show that intranasal instillation of OVA+lunasin significantly increases OVA-specific regulatory T cell (Treg) accumulation in the lung comparing to OVA only treatment. Taken together, our results suggest lunasin as an anti-inflammatory agent can be potentially used in asthma therapy or as an adjuvant to enhance the induction of antigen-specific Tregs and thus boost the efficacy of allergy immunotherapy. 相似文献