Emergent Bilinguals With Specific Reading Comprehension Deficits: A Comparative and Longitudinal Analysis.

This study centered on emergent bilingual (EB) students with specific reading comprehension deficits (S-RCD), that is, with poor reading comprehension despite solid word identification skills. The participants were 209 students in Grades 2 to 4, including both EBs and English monolinguals (EMs) with and without S-RCD. Mean comparisons indicated that EBs and EMs with S-RCD showed weaknesses relative to typically developing (TD) readers in oral language, word identification, inference making, and reading engagement, but not in executive functioning. Longitudinal analyses indicated that across two academic years S-RCD persisted for 41% of EBs and EMs alike. Altogether, the study extends research on EBs with S-RCD by identifying variables beyond oral language that may account for their reading comprehension difficulties and providing insight into the extent to which their reading comprehension and word identification performance levels evolve during elementary school. Furthermore, the findings point to the importance of early identification and intervention for weaknesses in reading comprehension and its component elements in both EBs and EMS.

The relationship between cognitive skills and reading comprehension of narrative and expository texts: A longitudinal study from Grade 1 to Grade 4.

Following the increased emphasis on expository text in early grades, this study examined narrative and expository reading comprehension growth in a sample of children who were followed longitudinally from grades 1 to 4, with the goals of explaining potential differences in children's overall performance and growth of narrative and expository text comprehension and identifying the cognitive factors that distinctly contribute to comprehension for each text type. We hypothesized that differences in reading comprehension growth of narrative and expository texts would be explained by various cognitive factors, specifically those related to executive functions (EF; e.g., working memory, planning/organization, shifting, and inhibition). At four annual time points, children (n= 94) read, retold (Recall), and answered questions (CompQ) about expository and narrative passages. Growth curve modeling was used to explore reading comprehension development across the two types of text. On average, results showed that children scored better on reading comprehension of narrative passages than they did on expository passages across all time points. After controlling for socioeconomic status (SES), vocabulary in 1st grade predicted 4th grade comprehension scores (Recall) for both narrative and expository passages, while word reading efficiency (WRE) in 1st grade predicted 4th grade comprehension scores (CompQ) for expository passages only. Additionally, WRE was associated with the growth of expository reading comprehension: children with higher WRE showed a faster growth rate for expository CompQ. The contribution of EF to text comprehension was largely confined to expository text, although planning and organization (measured using a direct cognitive assessment) in 1st grade also predicted 4th grade comprehension scores for narrative text Recall. For expository text comprehens ion, working memory, planning and organization, shifting, and inhibition (measured using a parent rating scale), predicted reading comprehension outcomes. Critically, 1st grade shifting and inhibition not only predicted 4th grade expository text comprehension (CompQ), but also modulated its growth rate: children with stronger shifting and inhibition had faster rates of growth. Together, these findings suggest that expository reading comprehension is (1) more difficult than narrative reading comprehension and (2) is associated with unique cognitive skills.

Modeling influenza transmission dynamics with media coverage data of the 2009 H1N1 outbreak in Korea.

Recurrent outbreaks of the influenza virus continue to pose a serious health threat all over the world. The role of mass media becomes increasingly important in modeling infectious disease transmission dynamics since it can provide public health information that influences risk perception and health behaviors. Motivated by the recent 2009 H1N1 influenza pandemic outbreak in South Korea, a mathematical model has been developed. In this work, a previous influenza transmission model is modified by incorporating two distinct media effect terms in the transmission rate function; (1) a theory-based media effect term is defined as a function of the number of infected people and its rage of change and (2) a data-based media effect term employs the real-world media coverage data during the same period of the 2009 influenza outbreak. The transmission rate and the media parameters are estimated through the least-squares fitting of the influenza model with two media effect terms to the 2009 H1N1 cumulative number of confirmed cases. The impacts of media effect terms are investigated in terms of incidence and cumulative incidence. Our results highlight that the theory-based and data-based media effect terms have almost the same influence on the influenza dynamics under the parameters obtained in this study. Numerical simulations suggest that the media can have a positive influence on influenza dynamics; more media coverage leads to a reduced peak size and final epidemic size of influenza.

TNFα regulates sugar transporters in the human intestinal epithelial cell line Caco-2.

PURPOSE: During intestinal inflammation TNFα levels are increased and as a consequence malabsorption of nutrients may occur. We have previously demonstrated that TNFα inhibits galactose, fructose and leucine intestinal absorption in animal models. In continuation with our work, the purpose of the present study was to investigate in the human intestinal epithelial cell line Caco-2, the effect of TNFα on sugar transport and to identify the intracellular mechanisms involved. METHODS: Caco-2 cells were grown on culture plates and pre-incubated during different periods with various TNFα concentrations before measuring the apical uptake of galactose, α-methyl-glucoside (MG) or fructose for 15 min. To elucidate the signaling pathway implicated, cells were pre-incubated for 30min with the PKA inhibitor H-89 or the PKC inhibitor chelerythrine, before measuring the sugar uptake. The expression in the apical membrane of the transporters implicated in the sugars uptake process (SGLT1 and GLUT5) was determined by Western blot. RESULTS: TNFα inhibited 0.1mM MG uptake after pre-incubation of the cells for 6-48h with the cytokine and in the absence of cytokine pre-incubation. In contrast, 5mM fructose uptake was stimulated by TNFα only after long pre-incubation times (24 and 48 h). These effects were mediated by the binding of the cytokine to its specific receptor TNFR1, present in the apical membrane of the Caco-2 cells. Analysis of the expression of the MG and fructose transporters at the brush border membrane of the cells, after 24h pre-incubation with the cytokine, revealed decrease on the amount of SGLT1 and increase on the amount of GLUT5 proteins. Short-term inhibition of MG transport by TNFα was not modified by H-89 but was blocked by chelerythrine. CONCLUSIONS: SGLT1 and GLUT5 expression in the plasma membrane is regulated by TNFα in the human epithelial cell line Caco-2 cells, leading to alteration on sugars transport, suggesting that TNFα could be considered as a physiological local regulator of nutrients absorption in response to an intestinal inflammatory status.

Luminal leptin inhibits L-glutamine transport in rat small intestine: involvement of ASCT2 and B0AT1.

L-glutamine is the primary metabolic fuel for enterocytes. Glutamine from the diet is transported into the absorptive cells by two sodium-dependent neutral amino acid transporters present at the apical membrane: ASCT2/SLC1A5 and B(0)AT1/SLC6A19. We have demonstrated that leptin is secreted into the stomach lumen after a meal and modulates the transport of sugars after binding to its receptors located at the brush border of the enterocytes. The present study was designed to address the effect of luminal leptin on Na(+)-dependent glutamine (Gln) transport in rat intestine and identify the transporters involved. We found that 0.2 nM leptin inhibited uptake of Gln and phenylalanine (Phe) (substrate of B(0)AT1) using everted intestinal rings. In Ussing chambers, 10 mM Gln absorption followed as Na(+)-induced short-circuit current was inhibited by leptin in a dose-dependent manner (maximum inhibition at 10 nM; I(C50) = approximately 0.1 nM). Phe absorption was also decreased by leptin. Western blot analysis after 3-min incubation of the intestinal loops with 10 mM Gln, showed marked increase of ASCT2 and B(0)AT1 protein in the brush-border membrane that was reduced by rapid preincubation of the intestinal lumen with 1 nM leptin. Similarly, the increase in ASCT2 and B(0)AT1 gene expression induced by 60-min incubation of the intestine with 10 mM Gln was strongly reduced after a short preincubation period with leptin. Altogether these data demonstrate that, in rat, leptin controls the active Gln entry through reduction of both B(0)AT1 and ASCT2 proteins traffic to the apical plasma membrane and modulation of their gene expression.

[Thyroglobulin levels in needle lymph node cytology for the detection of papillary thyroid cancer recurrence]. / Utilidad de la detección de tiroglobulina en el aspirado de punción ganglionar cervical en el seguimiento de pacientes con cancer papilar de tiroides.

BACKGROUND: During the detection of neck recurrence in patients with Papillary Thyroid Carcinoma (PTC), sometimes it is difficult to distinguish metastatic from inflammatory neck lymph nodes. The measurement of serum thyroglobulin (sTg) under thyroid hormone suppression therapy the presence of serum thyroglobulin antibodies (sAbTg), the diagnostic whole body scan and cytology can give false negative results. Measurement of thyroglobulin in the washout fluid from fine-needle aspiration biopsy (FNAB) of suspicious neck lymph nodes could improve the diagnostic accuracy. AIM: To evaluate the usefulness of detecting Tg in lymph nodes (LTg) suspicious by ultrasonography (US) and compare it to cytology. PATIENTS AND METHODS: Between the years 2004 and 2007 we prospectively studied 30 patients with PTC and cervical US findings of suspicious recurrence. LTg was assayed in US guided FNAB used for cytology. RESULTS: Sixteen out of 30 patients underwent surgery using as selective criteria an LTg higher than sTg or a positive cytology. Surgery confirmed the presence of metastasis in all 15 patients with positive LTg (8 with positive cytology) and in 1 patient with negative LTg and positive cytology (a case with undifferentiated thyroid cancer). The sensitivity was 93.7% for LTg and 56.2% for cytology. We identified by LTg 3 of 6 patients with undetectable sTg and positive sAbTg. CONCLUSIONS: The presence of LTg showed a higher sensitivity than cytology for the detection of cervical lymph node metastasis. This method is useful even in the presence of sAbTg.

Utilidad de la detección de tiroglobulina en el aspirado de punción ganglionar cervical en el seguimiento de pacientes con cancer papilar de tiroides / Thyroglobulin levels in needle lymph node cytology for the detection of papillary thyroid cancer recurrence

Background: During the detection ofneck recurrence in patients with Papillary Thyroid Carcinoma (PTC), sometimes it is difficult to distinguish metastatic from inflammatory neck lymph nodes. The measurement of serum thyroglobulin (sTg) under thyroid hormone suppression therapy the presence of serum thyroglobulin antibodies (sAbTg), the diagnostic whole body sean and cytology can give false negative results. Measurement of thyroglobulin in the washout fluid from fine-needle aspiration biopsy (FNAB) of suspicious neck lymph nodes could improve the diagnostic aecuracy Aim: To evaluate the usefulness of detecting Tg in lymph nodes (LTg) suspicious by ultrasonography (US) and compare it to cytology. Patients and Methods: Between the years 2004 and 2007 we prospectively studied 30 patients with PTC and cervical US findings of suspicious recurrence. LTg was assayed in US guided FNAB used for cytology. Results: Sixteen out of 30 patients underwent surgery using as selective criteria an LTg higher than sTg or a positive cytology. Surgery confirmed the presence of metástasis in all 15 patients with positive LTg (8 with positive cytology) and in 1 patient with negative LTg and positive cytology (a case with undifferentiated thyroid cancer). The sensitivity was 93.7 percent for LTg and 56.2 percent for cytology. We identified byLTg 3 of 6 patients with undetectable sTg and positive sAbTg. Conclusions: The presence of LTg showed a higher sensitivity than cytology for the detection of cervical lymph node metástasis. This method is useful even in the presence ofsAbTg.

Involvement of PKC and PKA in the inhibitory effect of leptin on intestinal galactose absorption.

Studies from our laboratory have demonstrated that leptin inhibits galactose absorption in vitro by acting on the Na(+)/glucose cotransporter SGLT1. Since PKC and PKA are involved in the regulation of SGLT1 and leptin is able to activate these kinases, we have investigated the possible implication of PKC and PKA in the inhibition of sugar absorption by leptin in rat small intestinal rings. Inhibition of 1 mM galactose uptake by 0.2 nM leptin is blocked by 2 microM chelerythrine, a PKC inhibitor, which by itself does not affect galactose uptake. However, 1 microM H-89, a PKA inhibitor, inhibits galactose uptake and does not block leptin inhibition. Biochemical assays show that the inhibitory effect of leptin is accompanied by a approximately 2-fold increase in PKA and PKC activity. These findings indicate that the activation of PKC is more relevant than PKA activation in the inhibition of galactose absorption by leptin.