1,259 research outputs found

    Inhibitors of neomycin phosphotransferase II enzyme-linked immunosorbent assay in grapevine (Vitis vinifera L.) leaves

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    Grapevine tissue extracts are rich in compounds that may inhibit detection and/or extraction of protein, DNA, and RNA. One such example can be found in the use of enzyme-linked immunosorbent assays (ELISA) to detect neomycin phosphotransferase II (NPTII) in leaf tissue. The objective of this study was to identify grape leaf components that interfere with protein detection via ELISA. A series of compounds were identified, and tartaric and ellagic acids were most inhibitory to NPTII detection. Polyphenolics as well as the low pH of grape leaf extracts also reduced the effectiveness of ELISA detection

    Thomas S. Kuhn's Lowell Lectures

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    For more information about this item, visit https://archivesspace.mit.edu/repositories/2/archival_objects/190184Before he wrote The Structure of Scientific Revolutions, Thomas Kuhn wrote The Quest for Physical Theory--a series of eight lectures that examine the nature of scientific knowledge, how it is created, and how it changes through time. Commissioned as public lectures in 1951 by Boston's Lowell Institute, The Quest for Physical Theory adopts the historical approach Kuhn would later refine in Structure. He surveys the history of physics from Aristotle to Newton, of atomism from antiquity to modern chemistry, and he examines the concepts of fields and subtle fluids as creative metaphors that guide research. In the last four lectures, he turns to logic and philosophy, psychology, and theories of language to explain the workings of "creative science" that are typically ignored by textbooks and many influential philosophers of science

    Inheritance of chloroplast DNA in two full-sib Vitis populations

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    The mode of transmission of chloroplasts in 2 grape populations was determined using restriction fragment length polymorphisms of chloroplast DNA (cpDNA) to trace the origin of plastids in the progeny. The populations examined were formed by crossing 2 complex interspecific hybrids: NY 62.136.2 x Yates and Cayuga White x Aurore. Analysis of the restriction banding patterns of total DNA of the 4 parents probed with cpDNA of grape and petunia revealed a high level of polymorphism (63 %) between parents ot the first cross and a low level of polymorphism (15 %) between the parents of the second cross. The restriction banding patterns of the 4 parents were unique, indicating that there were 4 distinct chloroplast genotypes. Analysis of the restriction banding patterns of total DNA of the progeny probed with cpDNA showed that all progeny from both crosses exhibited the banding pattern of the maternal parent. Thus, the mode of plastid transmission in these populations of grape was strictly maternal

    Insulin gene polymorphisms in type I diabetes, Addison's disease and the polyglandular autoimmune syndrome type II

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    Background: Polymorphisms within the insulin gene can influence insulin expression in the pancreas and especially in the thymus, where self-antigens are processed, shaping the T cell repertoire into selftolerance, a process that protects from ß-cell autoimmunity. Methods: We investigated the role of the -2221Msp(C/T) and -23HphI(A/T) polymorphisms within the insulin gene in patients with a monoglandular autoimmune endocrine disease [patients with isolated type 1 diabetes (T1D, n = 317), Addison´s disease (AD, n = 107) or Hashimoto´s thyroiditis (HT, n = 61)], those with a polyglandular autoimmune syndrome type II (combination of T1D and/or AD with HT or GD, n = 62) as well as in healthy controls (HC, n = 275). Results: T1D patients carried significantly more often the homozygous genotype "CC" -2221Msp(C/T) and "AA" -23HphI(A/T) polymorphisms than the HC (78.5% vs. 66.2%, p = 0.0027 and 75.4% vs. 52.4%, p = 3.7 × 10-8, respectively). The distribution of insulin gene polymorphisms did not show significant differences between patients with AD, HT, or APS-II and HC. Conclusion: We demonstrate that the allele "C" of the -2221Msp(C/T) and "A" -23HphI(A/T) insulin gene polymorphisms confer susceptibility to T1D but not to isolated AD, HT or as a part of the APS-II

    Reactions to uncertainty and the accuracy of diagnostic mammography.

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    BackgroundReactions to uncertainty in clinical medicine can affect decision making.ObjectiveTo assess the extent to which radiologists' reactions to uncertainty influence diagnostic mammography interpretation.DesignCross-sectional responses to a mailed survey assessed reactions to uncertainty using a well-validated instrument. Responses were linked to radiologists' diagnostic mammography interpretive performance obtained from three regional mammography registries.ParticipantsOne hundred thirty-two radiologists from New Hampshire, Colorado, and Washington.MeasurementMean scores and either standard errors or confidence intervals were used to assess physicians' reactions to uncertainty. Multivariable logistic regression models were fit via generalized estimating equations to assess the impact of uncertainty on diagnostic mammography interpretive performance while adjusting for potential confounders.ResultsWhen examining radiologists' interpretation of additional diagnostic mammograms (those after screening mammograms that detected abnormalities), a 5-point increase in the reactions to uncertainty score was associated with a 17% higher odds of having a positive mammogram given cancer was diagnosed during follow-up (sensitivity), a 6% lower odds of a negative mammogram given no cancer (specificity), a 4% lower odds (not significant) of a cancer diagnosis given a positive mammogram (positive predictive value [PPV]), and a 5% higher odds of having a positive mammogram (abnormal interpretation).ConclusionMammograms interpreted by radiologists who have more discomfort with uncertainty have higher likelihood of being recalled

    Natural infection of Run1-positive vines by naïve genotypes of Erysiphe necator

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    The Run1 locus for dominant resistance to powdery mildew (Erysiphe necator) has been successfully introgressed into Euvitis from Vitis rotundifolia. In the current study, Run1 vines were hybridized with breeding lines at Cornell University, and the presence of the locus was assayed using the markers GLP1-12 and VMC8g9. Signs of powdery mildew were observed on 14 of 113 Run1-positive seedlings in October 2010 in Geneva, N.Y. Severity of infection was lower for Run1-positive than for Run1-negative seedlings. Presence of mature cleistothecia suggested infection by at least two pathogen genotypes, which since V. rotundifolia is not grown within 800+ km of Geneva, N.Y., evolved from a pathogen population naïve to Run1 resistance. Therefore, caution in the deployment of the Run1 locus in new resistant cultivars is suggested so the effectiveness of Run1 does not diminish over time.

    Functional consequences of seven novel mutations in the CYP11B1 Gene: four mutations associated with nonclassic and three mutations causing classic 11 -Hydroxylase Deficiency

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    Context: Steroid 11β-hydroxylase (CYP11B1) deficiency (11OHD) is the second most common form of congenital adrenal hyperplasia (CAH). Cases of nonclassic 11OHD are rare compared with the incidence of nonclassic 21-hydroxylase deficiency. Objective: The aim of the study was to analyze the functional consequences of seven novel CYP11B1 mutations (p.M88I, p.W116G, p.P159L, p.A165D, p.K254_A259del, p.R366C, p.T401A) found in three patients with classic 11OHD, two patients with nonclassic 11OHD, and three heterozygous carriers for CYP11B1 mutations. Methods: We conducted functional studies employing a COS7 cell in vitro expression system comparing wild-type (WT) and mutant CYP11B1 activity. Mutants were examined in a computational three-dimensional model of the CYP11B1 protein. Results: All mutations (p.W116G, p.A165D, p.K254_A259del) found in patients with classic 11OHD have absent or very little 11β-hydroxylase activity relative to WT. The mutations detected in patients with nonclassic 11OHD showed partial functional impairment, with one patient being homozygous (p.P159L; 25% of WT) and the other patient compound heterozygous for a novel mild p.M88I (40% of WT) and the known severe p.R383Q mutation. The two mutations detected in heterozygous carriers (p.R366C, p.T401A) also reduced CYP11B1 activity by 23 to 37%, respectively. Conclusion: Functional analysis results allow for the classification of novel CYP11B1 mutations as causative for classic and nonclassic 11OHD, respectively. Four partially inactivating mutations are predicted to result in nonclassic 11OHD. These findings double the number of mild CYP11B1 mutations previously described as associated with mild 11OHD. Our data are important to predict phenotypic expression and provide important information for clinical and genetic counseling i

    Suicides in public places: findings from one English county

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    Little is known about where suicides take place. We collected data from coroners’ files on all suicides and undetermined deaths in one large English county from 2000 to 2004. The data show that >30% of suicides occurred in public places. A quarter of these involved jumping from a height and nearly a quarter involved car exhaust poisoning. Several sites were associated with multiple methods of suicide. Identifying and managing high-risk locations should be an important part of an overall suicide prevention strategy and is best tackled at local level

    Optimisation of air cooled, open-cathode fuel cells: Current of lowest resistance and electro-thermal performance mapping

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    Selecting the ideal operating point for a fuel cell depends on the application and consequent trade-off between efficiency, power density and various operating considerations. A systematic methodology for determining the optimal operating point for fuel cells is lacking; there is also the need for a single-value metric to describe and compare fuel cell performance. This work shows how the ‘current of lowest resistance’ can be accurately measured using electrochemical impedance spectroscopy and used as a useful metric of fuel cell performance. This, along with other measures, is then used to generate an ‘electro-thermal performance map’ of fuel cell operation. A commercial air-cooled open-cathode fuel cell is used to demonstrate how the approach can be used; in this case leading to the identification of the optimum operating temperature of ∼45 °C
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