Myocardial Infarction and Pathological Cardiac Remodeling
by Russell G. Rogers
The high prevalence of cardiovascular disease is responsible for approximately thirty-three percent of all-cause mortality in the United States. Additionally, nearly 1.5 million Americans experience a myocardial infarction each year, which directly contributes to mortality or secondary heart failure. Importantly, myocardial infarction has been associated with a series of pathological molecular and cellular changes that result in remodeling of the myocardium. Moreover, several lines of literature implicate oxidative stress as a primary feature of pathological remodeling following clinical and experimental myocardial infarction. However, the underlying mechanisms that drive oxidative-stress dependent cardiac remodeling following myocardial infarction have not been fully elucidated. Two cardinal features of pathological cardiac remodeling are interstitial fibrosis and hypertrophy and these processes appear to be under the strict control of connective tissue growth factor (CTGF), myocyte enhancer factor 2 (Mef2), and GATA4. These transcription factors are robustly up-regulated in response to pathological stimuli. Importantly, the transcriptional repressor Kruppel-like factor 15 (KLF15) negatively regulates the synthesis of CTGF and activity of Mef2 and GATA4. In response to in vivo pressure overload and in vitro oxidative stress, KLF15 is dramatically down-regulated which alleviates its inhibitory effects and thus, permits expression of pro-fibrotic and pro-hypertrophic genes. While anti-oxidant treatment has proven beneficial in preventing some indices of pathological remodeling, the redox-sensitive mechanisms responsible remain to be fully identified. To that end, this study attempts to identify the expression profile of KLF15 and its sensitivity to the redox status in the pathologic myocardium following infarction. Further, this study attempts to establish a novel role for KLF15 in the transcriptional regulation of pathological cardiac remodeling.
A Teacher’s Journey: Making Sense of How Reading Combined Text Genres Influenced Instructional Practices in a Sixth Grade Science Class
by Mesa Bryant Davis
This investigation explored how the experience of literacy integration, defined as using combined text genres (traditional science textbooks, popular science articles, and Adapted Primary Literature), influenced the instructional practices of a middle school science teacher (Phillips & Norris, 2009). The combined texts were put in a hermeneutic circle with in the classroom community and discussed (Eger, 1992). During the discussions the teacher monitored the students’ meaning construction processes and made metacognitive decisions about her instructional practices (Ruddell & Unrau, 2004). The participants were a sixth grade science teacher and ten (n=10) of her students at an academically rigorous, independent school in the southeastern United States. Classroom observations and interviews, both used as primary sources of data collection (DeWalt & DeWalt, 2002; Rubin & Rubin, 2005), were informed by other sources of data such as the collection of teacher and student artifacts and a questionnaire for the purpose of crystallization. The transcript data was transcribed, analyzed , and coded using performance/dialogic analysis. Categories from the codes were used to develop themes (Lichtman, 2013; Riessman, 2008) that were organized into a narrative that chronicled the teacher’s understanding of how the reading of combined text genres influenced her instructional practices. The findings are presented in the form of a case study (Yin, 2009). These assertions emerged from the data: (1) Melissa was able to make text visible (Lemke, 1990) and maintain an active learning environment while using minds-on instructional practices and (2) despite the tendency to compartmentalize each text genre, the teacher became metacognitive about her instructional practices. The implication is that literacy integration need not be a mystery or deterrent to science teachers (Shanahan, 1997). With the right resources, such as access to combined text genres, and through trial and error with a variety of instructional practices, teachers can successfully implement literacy integration into their classrooms.
Dialogic Reading: Language and Preliteracy Outcomes for Young Children with Disabilities
by Jacqueline Towson
Dialogic reading is an evidence based practice for preschool children who are typically developing or at-risk (WWC, 2007). However, there is limited research to evaluate if dialogic reading has similar positive effects on the language and preliteracy skills of preschool children with disabilities (WWC, 2010). This quasi-experimental study examined the effects of dialogic reading, with the incorporation of pause time, on the language and preliteracy skills of 42 preschool children with disabilities within 12 inclusive and self-contained preschool classrooms. Following random assignment of students at the level of the classrooms, participants were equally distributed into an intervention (n=21) and a comparison group (n=21). The intervention consisted of dialogic reading, with the incorporation of pause time, based on the Read Together, Talk Together (RTTT; Pearson Early Learning, 2006) program kit. The targeted outcomes were receptive language skills, expressive language skills, and preliteracy skills. Children received either dialogic reading or typical storybook reading for 10 to 15 minutes per day, three days per week, for six weeks (i.e., 18 sessions in total) in small groups. The Peabody Picture Vocabulary Test-4th Edition (PPVT -4; Dunn & Dunn, 2007), Expressive One-Word Picture Vocabulary Test-4th Edition (EOWPVT -4; Martin & Brownell, 2011), Get Ready to Read!-Revised (GRTR-R; Whitehurst & Lonigan, 2010), and the ‘Which One Doesn’t Belong’ and Picture Naming subtests of the Individual Growth and Development Indicators of Early Literacy (IGDis-EL; McConnell, Bradfield, Wackerle-Hollman, & Rodriquez, 2012) were used as pre- and post-test assessments. A researcher developed near transfer test of receptive and expressive vocabulary words was also administered pre- and post-intervention to determine if words specifically targeted during the intervention were learned. These standardized and researcher developed measures were analyzed with one-way ANCOVAs, using pretest scores and age as covariates to determine within and between group differences. The Johnson-Neyman procedure was utilized as necessary when violations of heterogeneity of slopes occurred. Following the intervention period, children in the intervention group scored significantly higher on the receptive and expressive near transfer vocabulary assessments. This occurred both for words that were specifically targeted during dialogic reading, as well as additional vocabulary words in the storybook.
Negotiating White Science in a Racially and Ethnically Diverse United States
by Patricia S. Dunac-Morgan
Scholars have empirically examined, rigorously developed, and analyzed various strategies to increase teachers’ capacity to reach students of color. These instructional strategies and philosophies include the study of multicultural education, teaching for social justice, and theorizing the connection between school and home life. While these instructional strategies highlight the need for a more inclusive approach, they do not center race enough. Culturally Relevant Pedagogy (CRP) is the pedagogical content and cultural knowledge a teacher exhibits (Ladson-Billings, 1995). CRP does not explicitly problematize race; yet the theory and praxis of CRP should include a critical analysis of race and racism. As an alternative framework that centers on race, researchers have begun to use Critical Race Theory (CRT) to explore aspects of race and racism in the teaching and learning realm. This qualitative case study examined how teachers make sense of their own racial selves in relation to teaching students from different racial backgrounds (Yin, 2008). Data collection included semi-structured interviews as the primary source of data. Classroom observations and researcher memos served as secondary sources of data (Seidman, 2005; Hatch, 2002: Prior, 2003). According to critical race theorists, narratives are essential when gathering vital sources of information, in that they make the social realities of people of color, as influenced by racism, observable to the world (Wallace & Brand, 2012). As such, CRT was used to identify whether there were any influences of the students’ racial identities on the teachers’ development and implementation of culturally responsive practices. The analysis revealed that: (1) teachers’ explicit confrontation with/of “otherness” as White female teachers and their critical awareness of societal influences on students of color presented more opportunities to be race-conscious and directly address institutional racism; and (2) teachers’ critical awareness of explicit and implicit power structures and how these relationships ate embedded in a “hidden curriculum” influenced their beliefs and instructional practices. These findings communicate the significance of White female teachers understanding of issues specific to urban schools, and their efforts to find ways to remedy those issues to make learning meaningful, purposeful, and authentic for students of color.