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101.
Eider Pascual Corrales Rosa Maria Príncipe Sara Laguna Muro Fernando Martínez Regueira Juan Manuel Alcalde Navarrete Francisco Guillén Grima Juan Carlos Galofré 《Endocrinología y nutrición》2012,59(3):169-173
ObjectiveRisk factors for differentiated thyroid carcinoma (DTC) are poorly understood, but serum TSH levels, thyroid nodularity, and presence of autoimmunity are well-recognized factors that modulate DTC prevalence. TSH stimulates proliferation of both normal and neoplastic follicular cells. Consequently, thyroid-stimulating immunoglobulins (TSI), because of its TSH-like action, should induce DTC progression in patients with Graves’ disease (GD). The study objective was to compare the prevalence of incidental DTC in patients undergoing thyroidectomy for benign thyroid disease.MethodsThe pathology reports of 372 patients with preoperative diagnosis of euthyroid multinodular goiter (EMG) or hyperthyroidism were reviewed. Scintigraphy results and serum TSI levels were used to diagnosed either GD or hyperactive MG (HMG) to hyperthyroid subjects. Prevalence of DTC in each category was calculated using a Chi-square test.ResultsEMG, GD, and HMG were diagnosed in 221, 125, and 26 patients. There were 58 DTCs, distributed as follows [n (%)]: EMG, 49 (22.2%); GD, 8 (6.4%), and HMG, 1 (3.8%). Difference in prevalence of incidental DTC between the groups was statistically significant (p < 0.001). After adjustment for age, patients with EMG had a greater DTC prevalence than GD patients, with an OR of 4.17 (p < 0.001). Tumor size (mm, mean ± SD) was 6.92 ± 11.26, 1.97 ± 1.85, and 9.0 for EMG, GD and HMG respectively (p = 0.017).ConclusionsIncidental DTC was less prevalent in GD as compared to EMG irrespective of age. This finding may suggest a predisposition to develop DTC in patients with thyroid nodular disease and/or a potential effect of autoimmunity to protect against development of neoplastic disease. 相似文献
102.
The genetic network of greater sage‐grouse: Range‐wide identification of keystone hubs of connectivity 下载免费PDF全文
Todd B. Cross Michael K. Schwartz David E. Naugle Brad C. Fedy Jeffrey R. Row Sara J. Oyler‐McCance 《Ecology and evolution》2018,8(11):5394-5412
Genetic networks can characterize complex genetic relationships among groups of individuals, which can be used to rank nodes most important to the overall connectivity of the system. Ranking allows scarce resources to be guided toward nodes integral to connectivity. The greater sage‐grouse (Centrocercus urophasianus) is a species of conservation concern that breeds on spatially discrete leks that must remain connected by genetic exchange for population persistence. We genotyped 5,950 individuals from 1,200 greater sage‐grouse leks distributed across the entire species’ geographic range. We found a small‐world network composed of 458 nodes connected by 14,481 edges. This network was composed of hubs—that is, nodes facilitating gene flow across the network—and spokes—that is, nodes where connectivity is served by hubs. It is within these hubs that the greatest genetic diversity was housed. Using indices of network centrality, we identified hub nodes of greatest conservation importance. We also identified keystone nodes with elevated centrality despite low local population size. Hub and keystone nodes were found across the entire species’ contiguous range, although nodes with elevated importance to network‐wide connectivity were found more central: especially in northeastern, central, and southwestern Wyoming and eastern Idaho. Nodes among which genes are most readily exchanged were mostly located in Montana and northern Wyoming, as well as Utah and eastern Nevada. The loss of hub or keystone nodes could lead to the disintegration of the network into smaller, isolated subnetworks. Protecting both hub nodes and keystone nodes will conserve genetic diversity and should maintain network connections to ensure a resilient and viable population over time. Our analysis shows that network models can be used to model gene flow, offering insights into its pattern and process, with application to prioritizing landscapes for conservation. 相似文献
103.
DNA vaccines consisted of tumor-associated antigen (TAA) are well suited for immunotherapy against tumor. The construct can
contain TAA fused to an appropriate molecule (biologic adjuvant) to improve the efficacy of anti-tumor immune response. Heat
shock protein 70 (HSP70) has been shown to be an excellent candidate, capable of cross-priming TAA by antigen presenting cells
leading to a robust T-cell response. However, the relationship between strong T-cell responses and tumor rejection is not
always mutually exclusive, for which TAA loss or activation of suppressive mechanisms may occur. HSP70 fused to downstream
of Her2/neu as DNA vaccine has been shown to be efficient against Her2-expressing tumors. In this study, we examined if N-terminally
fusion of Her2/neu to HSP70 could also improve efficiency of Her2/neu DNA vaccine. Therefore, mice with an established Her2/neu
expressing tumor were immunized with DNA vaccine consisting of extracellular and trans-membrane domain (EC+TM) of rat Her2/neu
alone or N-terminally fused to HSP70 and immune response was evaluated. Administration of rat Her2/neu led to partial control
of tumor progression. Surprisingly, fusion of HSP70 to N-terminal of rat Her2/neu led to tumor progression. Our result proposes
that fusion direction of biologic adjuvant is an important consideration when Her2/neu is used. 相似文献
104.
Carolina Escobedo-Martínez Sara Cruz-Morales Mabel Fragoso-Serrano M. Mukhlesur Rahman Simon Gibbons Rogelio Pereda-Miranda 《Phytochemistry》2010,71(14-15):1796-1801
Pescaprein XVIII (1), a type of bacterial efflux pump inhibitor, was obtained from the CHCl3-soluble resin glycosides of beach morning glory (Ipomoea pes-caprae). The glycosidation sequence for pescaproside C, the glycosidic acid core of the lipophilic macrolactone 1 containing d-xylose and l-rhamnose, was characterized by means of several NMR techniques and FAB mass spectrometry. Recycling HPLC also yielded eight non-cytotoxic bacterial resistance modifiers, the two pescapreins XIX (2) and XX (3) as well as the known murucoidin VI (4), pecapreins II (6) and III (7), and stoloniferins III (5), IX (8) and X (9), all of which contain simonic acid B as their oligosaccharide core. Compounds 1–9 were tested for in vitro antibacterial and resistance-modifying activity against strains of Staphylococcus aureus possessing multidrug resistance efflux mechanisms. All of the pescapreins potentiated the action of norfloxacin against the NorA over-expressing strain by 4-fold (8 μg/mL from 32 μg/mL) at a concentration of 25 μg/mL. 相似文献
105.
Fleming SD Pope MR Hoffman SM Moses T Bukovnik U Tomich JM Wagner LM Woods KM 《Journal of immunology (Baltimore, Md. : 1950)》2010,185(10):6168-6178
Reperfusion of ischemic tissue induces significant tissue damage in multiple conditions, including myocardial infarctions, stroke, and transplantation. Although not as common, the mortality rate of mesenteric ischemia/reperfusion (IR) remains >70%. Although complement and naturally occurring Abs are known to mediate significant damage during IR, the target Ags are intracellular molecules. We investigated the role of the serum protein, β2-glycoprotein I as an initiating Ag for Ab recognition and β2-glycoprotein I (β2-GPI) peptides as a therapeutic for mesenteric IR. The time course of β2-GPI binding to the tissue indicated binding and complement activation within 15 min postreperfusion. Treatment of wild-type mice with peptides corresponding to the lipid binding domain V of β2-GPI blocked intestinal injury and inflammation, including cellular influx and cytokine and eicosanoid production. The optimal therapeutic peptide (peptide 296) contained the lysine-rich region of domain V. In addition, damage and most inflammation were also blocked by peptide 305, which overlaps with peptide 296 but does not contain the lysine-rich, phospholipid-binding region. Importantly, peptide 296 retained efficacy after replacement of cysteine residues with serine. In addition, infusion of wild-type serum containing reduced levels of anti-β2-GPI Abs into Rag-1(-/-) mice prevented IR-induced intestinal damage and inflammation. Taken together, these data suggest that the serum protein β2-GPI initiates the IR-induced intestinal damage and inflammatory response and as such is a critical therapeutic target for IR-induced damage and inflammation. 相似文献
106.
Jeemeng Lao Ai Oikawa Jennifer R. Bromley Peter McInerney Anongpat Suttangkakul Andreia M. Smith‐Moritz Hector Plahar Tsan‐Yu Chiu Susana M. González Fernández‐Niño Berit Ebert Fan Yang Katy M. Christiansen Sara F. Hansen Solomon Stonebloom Paul D. Adams Pamela C. Ronald Nathan J. Hillson Masood Z. Hadi Miguel E. Vega‐Sánchez Dominique Loqué Henrik V. Scheller Joshua L. Heazlewood 《The Plant journal : for cell and molecular biology》2014,79(3):517-529
The glycosyltransferases (GTs) are an important and functionally diverse family of enzymes involved in glycan and glycoside biosynthesis. Plants have evolved large families of GTs which undertake the array of glycosylation reactions that occur during plant development and growth. Based on the Carbohydrate‐Active enZymes (CAZy) database, the genome of the reference plant Arabidopsis thaliana codes for over 450 GTs, while the rice genome (Oryza sativa) contains over 600 members. Collectively, GTs from these reference plants can be classified into over 40 distinct GT families. Although these enzymes are involved in many important plant specific processes such as cell‐wall and secondary metabolite biosynthesis, few have been functionally characterized. We have sought to develop a plant GTs clone resource that will enable functional genomic approaches to be undertaken by the plant research community. In total, 403 (88%) of CAZy defined Arabidopsis GTs have been cloned, while 96 (15%) of the GTs coded by rice have been cloned. The collection resulted in the update of a number of Arabidopsis GT gene models. The clones represent full‐length coding sequences without termination codons and are Gateway® compatible. To demonstrate the utility of this JBEI GT Collection, a set of efficient particle bombardment plasmids (pBullet) was also constructed with markers for the endomembrane. The utility of the pBullet collection was demonstrated by localizing all members of the Arabidopsis GT14 family to the Golgi apparatus or the endoplasmic reticulum (ER). Updates to these resources are available at the JBEI GT Collection website http://www.addgene.org/ . 相似文献
107.
Haytham O. Tawfik Moataz A. Shaldam Alessio Nocentini Rofaida Salem Hadia Almahli Sara T. Al-Rashood Claudiu T. Supuran Wagdy M. Eldehna 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1043
Carbonic anhydrases (CAs) are one of the promising targets for the development of anticancer agents. CA isoforms are implicated in various physiological processes and are expressed in both normal and cancerous cells. Thus, non-isoform selective inhibitors are associated with several side effects. Consequently, designing selective inhibitors towards cancer-related hCA IX/XII rather than the ubiquitous cytosolic isozymes hCA I and II is the main research objective in the field. Herein, a new series of 3-(6-methylpyridin-2-yl)coumarin derivatives 3 and 5a–o was designed and synthesised. The CA inhibition activities for the synthesised coumarins were analysed on isoforms hCA I, II, IX, and XII. Interestingly, both cancer-linked isoforms hCA IX/XII were inhibited by the prepared coumarins with inhibition constants ranging from sub- to low-micromolar range, whereas hCA I and II isoforms haven’t been inhibited up to 100 µM. Furthermore, the target coumarins were assessed for their antitumor activity on NCI-59 human cancer types. 相似文献
108.
Elizabeth J Beckman Felipe Martins Taichi A Suzuki Ke Bi Sara Keeble Jeffrey M Good Andreas S Chavez Mallory A Ballinger Kennedy Agwamba Michael W Nachman 《Genetics》2022,220(2)
Understanding the genetic basis of environmental adaptation in natural populations is a central goal in evolutionary biology. The conditions at high elevation, particularly the low oxygen available in the ambient air, impose a significant and chronic environmental challenge to metabolically active animals with lowland ancestry. To understand the process of adaptation to these novel conditions and to assess the repeatability of evolution over short timescales, we examined the signature of selection from complete exome sequences of house mice (Mus musculus domesticus) sampled across two elevational transects in the Andes of South America. Using phylogenetic analysis, we show that house mice colonized high elevations independently in Ecuador and Bolivia. Overall, we found distinct responses to selection in each transect and largely nonoverlapping sets of candidate genes, consistent with the complex nature of traits that underlie adaptation to low oxygen availability (hypoxia) in other species. Nonetheless, we also identified a small subset of the genome that appears to be under parallel selection at the gene and SNP levels. In particular, three genes (Col22a1, Fgf14, and srGAP1) bore strong signatures of selection in both transects. Finally, we observed several patterns that were common to both transects, including an excess of derived alleles at high elevation, and a number of hypoxia-associated genes exhibiting a threshold effect, with a large allele frequency change only at the highest elevations. This threshold effect suggests that selection pressures may increase disproportionately at high elevations in mammals, consistent with observations of some high-elevation diseases in humans. 相似文献
109.
Clinical trials use placebos with the assumption that they are inert, thus all placebos are considered to be equal. Here we show that this assumption is wrong and that different placebo procedures are associated to different therapeutic rituals which, in turn, trigger different mechanisms and produce different therapeutic outcomes. We studied high altitude, or hypobaric hypoxia, headache, in which two different placebos were administered. The first was placebo oxygen inhaled through a mask, whereas the second was placebo aspirin swallowed with a pill. Both placebos were given after a conditioning procedure, whereby either real oxygen or real aspirin was administered for three consecutive sessions to reduce headache pain. We found that after real oxygen conditioning, placebo oxygen induced pain relief along with a reduction in ventilation, blood alkalosis and salivary prostaglandin (PG)E2, yet without any increase in blood oxygen saturation (SO2). By contrast, after real aspirin conditioning, placebo aspirin induced pain relief through the inhibition of all the products of cyclooxygenase, that is, PGD2, PGE2, PGF2, PGI2, thromboxane (TX)A2, without affecting ventilation and blood alkalosis. Therefore, two different placebos, associated to two different therapeutic rituals, used two different pathways to reduce headache pain. The analgesic effect following placebo oxygen was superior to placebo aspirin. These findings show that different placebos may use different mechanisms to reduce high altitude headache, depending on the therapeutic ritual and the route of administration. In clinical trials, placebos and outcome measures should be selected very carefully in order not to incur in wrong interpretations. 相似文献
110.
Todd J Menkhaus Sara U Eriksson Paul B Whitson Charles E Glatz 《Biotechnology and bioengineering》2002,77(2):148-154
Host selection can be a strategy to simplify downstream processing for protein recovery. Advancing capabilities for using plants as hosts offers new host opportunities that have received only limited attention from a downstream processing perspective. Here, we investigated the potential of using a polycationic precipitating agent (polyethylenimine; PEI) to precipitate an acidic model protein (beta-glucuronidase; GUS) from aqueous plant extracts. To assess the potential of host selection to enhance the ease of recovery, the same procedure was applied to oilseed extracts of canola, corn (germ), and soy. For comparison, PEI precipitation of GUS was also evaluated from a crude bacterial fermentation broth. Two versions of the target protein were investigated--the wild-type enzyme (WTGUS) and a genetically engineered version containing 10 additional aspartates on each of the enzyme's four homologous subunits (GUSD10). It was found that canola was the most compatible expression host for use with this purification technique. GUS was completely precipitated from canola with the lowest dosage of PEI (30 mg PEI/g total protein), and over 80% of the initial WTGUS activity was recovered with 18-fold purification. Precipitation from soy gave yields over 90% for WTGUS but only 1.3-fold enrichment. Corn, although requiring the most PEI relative to total protein to precipitate (210 mg PEI/g total protein for 100% precipitation), gave intermediate results, with 81% recovery of WTGUS activity and a purification factor of 2.6. The addition of aspartate residues to the target protein did not enhance the selectivity of PEI precipitation in any of the systems tested. In fact, the additional charge reduced the ability to recover GUSD10 from the precipitate, resulting in lower yields and enrichment ratios compared to WTGUS. Compared to the bacterial host, plant systems provided lower polymer dosage requirements, higher yields of recoverable activity and greater purification factors. 相似文献