In this review article, emphasis is placed on the critical survey of available data concerning modified nucleobase and 2-deoxyribose products that have been identified in cellular DNA following ...exposure to a wide variety of oxidizing species and agents including, hydroxyl radical, one-electron oxidants, singlet oxygen, hypochlorous acid and ten-eleven translocation enzymes. In addition, information is provided about the generation of secondary oxidation products of 8-oxo-7,8-dihydroguanine and nucleobase addition products with reactive aldehydes arising from the decomposition of lipid peroxides. It is worth noting that the different classes of oxidatively generated DNA damage that consist of single lesions, intra- and interstrand cross-links were unambiguously assigned and quantitatively detected on the basis of accurate measurements involving in most cases high performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry. The reported data clearly show that the frequency of DNA lesions generated upon severe oxidizing conditions, including exposure to ionizing radiation is low, at best a few modifications per 106 normal bases. Application of accurate analytical measurement methods has also allowed the determination of repair kinetics of several well-defined lesions in cellular DNA that however concerns so far only a restricted number of cases.
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•HPLC based methods are appropriate for monitoring oxidatively damage to DNA.•Single base lesions, intra- and interstrand cross-links were identified in cellular DNA.•Other modifications included halogenated bases and adducts with reactive aldehydes.•Paucity of reliable data on the base excision repair of oxidized bases in cells.
Specific learning disabilities (SLDs) are highly relevant to the science and practice of psychology, both historically and currently, exemplifying the integration of interdisciplinary approaches to ...human conditions. They can be manifested as primary conditions-as difficulties in acquiring specific academic skills-or as secondary conditions, comorbid to other developmental disorders such as attention-deficit hyperactivity disorder. In this synthesis of historical and contemporary trends in research and practice, we mark the 50th anniversary of the recognition of SLDs as a disability in the United States. Specifically, we address the manifestations, occurrence, identification, comorbidity, etiology, and treatment of SLDs, emphasizing the integration of information from the interdisciplinary fields of psychology, education, psychiatry, genetics, and cognitive neuroscience. SLDs, exemplified here by specific word reading, reading comprehension, mathematics, and written expression disabilities, represent spectrum disorders, each occurring in approximately 5% to 15% of the school-aged population. In addition to risk for academic deficiencies and related functional social, emotional, and behavioral difficulties, those with SLDs often have poorer long-term social and vocational outcomes. Given the high rate of occurrence of SLDs and their lifelong negative impact on functioning if not treated, it is important to establish and maintain effective prevention, surveillance, and treatment systems involving professionals from various disciplines trained to minimize the risk and maximize the protective factors for SLDs.
Relations between reading and writing have been studied extensively, but the less is known about the developmental nature of their interrelations. This study applied latent change score modeling to ...investigate longitudinal relations between reading and writing skills at the word, sentence, and text levels. Latent change score models were used to compare unidirectional pathways (reading-to-writing and writing-to-reading) and bidirectional pathways in a test of nested models. Participants included 316 boys and girls who were assessed annually in Grades 1 through 4. Measures of reading included pseudoword decoding, sentence reading efficiency, oral reading fluency and passage comprehension. Measures of writing included spelling, a sentence-combining task, and writing prompts. Findings suggest that a reading-to-writing model better described the data for the word and text levels of language, but a bidirectional model best fit the data at the sentence level.
The purpose of this meta-analysis was to examine the comprehension problems of children who have a specific reading comprehension deficit (SCD), which is characterized by poor reading comprehension ...despite adequate decoding. The meta-analysis included 86 studies of children with SCD who were assessed in reading comprehension and oral language (vocabulary, listening comprehension, storytelling ability, and semantic and syntactic knowledge). Results indicated that children with SCD had deficits in oral language (d = -0.78, 95% confidence interval, CI -0.89, -0.68, but these deficits were not as severe as their deficit in reading comprehension (d = -2.78, 95% CI -3.01, -2.54). When compared with reading comprehension agematched normal readers, the oral language skills of the two groups were comparable (d = 0.32, 95% CI -0.49, 1.14), which suggests that the oral language weaknesses of children with SCD represent a developmental delay rather than developmental deviance. Theoretical and practical implications of these findings are discussed.
The present study followed a sample of first-grade (N = 316, Mage = 7.05 at first test) through fourth-grade students to evaluate dynamic developmental relations between vocabulary knowledge and ...reading comprehension. Using latent change score modeling, competing models were fit to the repeated measurements of vocabulary knowledge and reading comprehension to test for the presence of leading and lagging influences. Univariate models indicated growth in vocabulary knowledge, and reading comprehension was determined by two parts: constant yearly change and change proportional to the previous level of the variable. Bivariate models indicated previous levels of vocabulary knowledge acted as leading indicators of reading comprehension growth, but the reverse relation was not found. Implications for theories of developmental relations between vocabulary and reading comprehension are discussed.
Traditional approaches for evaluating aesthetic value rely on surveys or interviews. Social media provides a new type of crowdsourcing data to examine the relationships between aesthetic value and ...citizens' activities. The main goal of this paper was to evaluate aesthetic value in Nebraska by using citizen-reported geo-tagged photographs posted on two social media sites - Panoramio and Flickr. The study used the application programming interface from Panoramio and Flickr to obtain the latitude and longitude of the geo-tagged photographs, and then used ArcGIS spatial statistical tools to examine spatial patterns with areas of aesthetic value in Nebraska. The outcomes identified the clusters of pictures with the locations of ecosystem service provisioning areas of aesthetic value in Nebraska, identified new areas with aesthetic value, and drew comparisons with local and regional population distribution. This study provided an innovative approach to using crowdsourcing data to verify the value of ecosystem services.
Dichotomous dermatologic depictions of heroes and villains in movies have been used since the silent film age.
To evaluate the hero-villain skin dichotomy in film by (1) identifying dermatologic ...findings of the all-time top 10 American film villains, (2) comparing these dermatologic findings to the all-time top 10 American film heroes quantitatively and qualitatively, and (3) analyzing dermatologic portrayals of film villains in depth.
In this cross-sectional study, dermatologic findings for film heroes and villains in mainstream media were identified and compared quantitatively using a χ2 test with α < .05, as well as qualitatively. The all-time top 10 American film villains and heroes were obtained from the American Film Institute 100 Greatest Heroes and Villains List.
Primary outcomes include identification and frequencies of dermatologic findings of the top 10 film villains and of the top 10 film heroes.
Six (60%) of the all-time top 10 American film villains have dermatologic findings, including cosmetically significant alopecia (30%), periorbital hyperpigmentation (30%), deep rhytides on the face (20%), multiple facial scars (20%), verruca vulgaris on the face (20%), and rhinophyma (10%). The top 10 villains have a higher incidence of significant dermatologic findings than the top 10 heroes (60% vs 0%; P = .03).
Dermatologic findings of the all-time top 10 American villains are used in film to highlight the dichotomy of good and evil, which may foster a tendency toward prejudice in our society directed at those with skin disease.
The present study examined the reading comprehension and receptive vocabulary skills of children with poor reading comprehension despite adequate decoding using a regression-based matching technique. ...Participants included five cohorts of children who were identified as typical readers (N = 70,493 - 75,553) or as children with specific reading comprehension difficulties (N = 480 - 8,717). Across cohorts, children with specific reading comprehension difficulties exhibited oral language difficulties based on a measure of vocabulary; however, the observed weakness in vocabulary was not as severe as their reading comprehension difficulties. Results from the regression-based matching technique suggested that the vocabulary weakness for these children is better characterized as a developmental delay rather than a developmental deficit. This outcome also emerged when more stringent criteria were used to identify subgroups of readers. Although children with poor reading comprehension despite adequate decoding have a weakness in at least one aspect of oral language, their oral language weakness does not account for the severity of their reading comprehension difficulties. Theoretical and practical implications are discussed.
Educational Impact and Implications Statement
The present investigation examined the reading comprehension and receptive vocabulary skills of five cohorts of children who were identified as having poor reading comprehension despite adequate word reading skills. Across cohorts, children with reading comprehension problems had a weakness in receptive vocabulary knowledge; however, this weakness was less severe than their reading comprehension problem. Results also suggested that the observed vocabulary weakness was developmentally delayed, indicating that it is better characterized as a correlate rather than a cause of children's reading comprehension problems. Although children with poor reading comprehension despite adequate word reading skills have a weakness in at least one aspect of oral language, this weakness does not account for the severity of their reading comprehension difficulties.
The reaction of hydroxyl radical (HO•) with thymine in DNA generates 5-(uracilyl)-methyl radicals (T•) and the corresponding methylperoxyl radical (TOO•) in the presence of O2, which in turn ...propagates damage by reacting with a vicinal nucleobase. This leads to so-called double or tandem lesions. Because methyl oxidation products of thymine are major products, we investigated the reactivity of TOO• using a photolabile precursor: 5-(phenylthiomethyl)uracil (TSPh). The precursor was prepared and incorporated into a DNA trinucleotide: 5′-d(GpTSPhpA)-3′ (G-TSPh-A). Upon photolysis, the resulting products were characterized by LC-MS/MS. Thereby, we identified four tandem lesions involving GpT, which include either 2,6-diamino-4-hydroxy-5-formamidopyrimidine (fapyG) or 8-oxo-7,8-dihydroguanine (oxoG) in tandem with either 5-formyluracil (fU) or 5-hydroxymethyluracil (hmU). The formation of these tandem lesions is explained by initial addition of TOO• to the C8 of guanine moiety, giving an N7-guanine cross-linked radical. The latter radical undergoes either reduction to an 7,8-saturated endoperoxide or oxidation to an 7,8-unsaturated endoperoxide, which transform into fapyG-fU-A and oxoG-fU-A, respectively. This is supported by the effect of a reducing (dithiothreitol) and oxidizing agent (Fe3+) on product formation. This study expands the repertoire of tandem lesions that can occur at GpT sequences and underlines the importance of redox environment.
The purpose of this review was to introduce readers of Child Development to the meta-analytic structural equation modeling (MASEM) technique. Provided are a background to the MASEM approach, a ...discussion of its utility in the study of child development, and an application of this technique in the study of reading comprehension (RC) development. MASEM uses a two-stage approach: first, it provides a composite correlation matrix across included variables, and second, it fits hypothesized a priori models. The provided MASEM application used a large sample (N = 1,205,581) of students (ages 3.5-46.225) from 155 studies to investigate the factor structure and relations among components of RC. The practical implications of using this technique to study development are discussed.