Although permissive hypercapnia improves the prognosis of patients with acute respiratory distress syndrome, it has not been conclusively determined whether hypercapnic acidosis (HA) is harmful or beneficial to sustained inflammation of the lung. The present study was designed to explore the molecular mechanism of HA in modifying lipopolysaccharide (LPS)-associated signals in pulmonary endothelial cells. LPS elicited degradation of inhibitory protein kappaB (IkappaB)-alpha, but not IkappaB-beta, resulting in activation of nuclear factor (NF)-kappaB in human pulmonary artery endothelial cells. Exposure to HA significantly attenuated LPS-induced NF-kappaB activation through suppressing IkappaB-alpha degradation. Isocapnic acidosis and buffered hypercapnia showed qualitatively similar but quantitatively smaller effects. HA did not attenuate the LPS-enhanced activation of activator protein-1. Following the reduced NF-kappaB activation, HA suppressed the mRNA and protein levels of intercellular adhesion molecule-1 and interleukin-8, resulting in a decrease in both lactate dehydrogenase release into the medium and neutrophil adherence to LPS-activated human pulmonary artery endothelial cells. In contrast, HA did not inhibit LPS-enhanced neutrophil expression of integrin, Mac-1. Based on these findings, we concluded that hypercapnic acidosis would have anti-inflammatory effects essentially through a mechanism inhibiting NF-kappaB activation, leading to downregulation of intercellular adhesion molecule-1 and interleukin-8, which in turn inhibits neutrophil adherence to pulmonary endothelial cells.
This study examined the effectiveness of explicit instruction of vocabulary learning strategies (VLSs) over a 10-week semester with a group of 146 female EFL learners from two Japanese universities. A vocabulary test and questionnaires on VLSs and motivation were administered at the beginning of the course. The learners were divided into two groups based on the vocabulary test results: an experimental group and a control group. Only the experimental group received explicit instruction on VLSs in combination with their regular language lessons. The same instruments were re-administered at the end of the course to examine the changes in both the questionnaire responses and test scores. Qualitative analyses were also conducted to explore the findings in detail. The results show that the experimental group outperformed the control group in the vocabulary test. It was also found that (1) strategy training was effective for both changing the repertoire of strategies used and improving their frequency of use, (2) the training increased the use of certain strategies more than it did for other strategies, and (3) different types of learners exhibited different responses to the strategy instruction. This study's findings contribute to a better understanding of strategy instruction in general and VLSs in particular.
This article reports on a qualitative study conducted in the Japanese foreign language (FL) context about good foreign language learners, in which the author analyzes the strategy use reported in 67 books on ''how I have learned a foreign language.'' Results suggest that there are strategies especially favored in the Japanese FL context and that the use of some strategies seems to be closely connected to specific stages of learning. Some research implications are also discussed.
The aim of this study is to reveal the differences in the process of learning reading strategies by EFL learners whose English proficiency levels differ. For this purpose, portfolios made by 10 Japanese female college students learning English (five in the higher proficiency group and the other five in the lower) were analyzed. The results found six prominent differences between the two groups. The first difference is the amount of description recorded in each portfolio. The second, third, and fourth differences concern the understanding of the purpose and the merit of each strategy use, of the conditions in which each strategy is used effectively, and of the combined use of strategies. Also, the timing for and the method for evaluating efficacy of strategy use are different between the two groups. After the full descriptions of these six differences with samples from portfolios, some pedagogical and research implications for strategy instruction are made.Keywords: Reading strategies; Portfolios; Learners' English proficiency level IntroductionSince the use of strategies has been considered to be one of the important factors for successful language learning, strategy instruction by various methods has been implemented in many countries (e.g., Ayaduray and Jacbos, 1997;Dreyer and Nel, 2003;Oxford et al., 1990). At the same time, the efficacy of such strategy instruction has been ascertained, to the best of the authors' knowledge, in terms of one or more of three criteria: learners' language proficiency, the frequency of their strategy use, or their reactions to the strategy instruction. As for the first criterion, Kern (1989), for example, trained for one semester 53 American university students learning French to use cognitive strategies for reading comprehension. His results showed that the instruction had some positive effects on the improvement of the learners' (especially, the lower proficiency learners') reading comprehension ability. In Takeuchi and Wakamoto (2001), strategies for writing, speaking, reading, and vocabulary building were taught to 21 Japanese university students learning EFL. They found that the frequency of their participants' strategy use increased and the higher frequency was retained for at least two and a half months after the instruction. Ayaduray and Jacbos (1997) also confirmed the efficacy of strategy instruction in terms of the frequency of strategy use by teaching 32 high school students learning English as a second language to use cognitive strategies for speaking and listening. Dadour and Robbins (1996), among others, investigated the efficacy of the strategy instruction according to learners' reaction. In their study, a total of 46 Japanese college students learning EFL were trained to use cognitive strategies for speaking and listening; the researchers found that they reacted positively to the instruction. Cohen et al. (1996) evaluated the efficacy of strategy instruction based on two criteria out of three mentioned above. They taught strategies for speaking to 55 Ame...
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