The acute effects of nonstructural-1 protein dengue virus type 2 on wet liver weight, zonulin expression and serum zonulin.

Background and Objectives: Intestinal leakage commonly occurs in severe dengue infection with zonulin as a biomarker. The aim of this study was to determine the effects of NS1 on liver weight, zonulin expression and serum zonulin levels. Materials and Methods: This laboratory experiment used 18 ddY mice, which were randomly divided into control (C), PBS (T1), and PBS + NS1 (T2) groups. Mice in the T1 and T2 groups were intravenously injected with 500 µl PBS only and 50 µg NS1 respectively. Mice blood samples were collected before and after three-day treatment for measurement of zonulin level. The fresh liver was weighted directly and were then used for immunostaining. Results: The C group had lower wet liver weight compared to the T groups (p=0.001). Increased expression of liver zonulin was found in the T2 group, significant different from the C (p=0.014) and T1 groups (p=0.020). After treatment, serum zonulin levels in the T1 group was higher than that of the T1 group before treatment (p=0.035) but not in control (p=0.753) and T2 groups (p=0.869). Conclusion: Administration of 50 µg NS 1 increases wet liver weight and zonulin expression in hepatocytes, but did not increase serum zonulin levels in ddY mice.

Electroencephalography (EEG) Frontal Alpha Asymmetry Index as an Indicator of Children's Emotions in the Three Quran Learning Methods: Visual, Auditory, and Memory.

Objective: Quran memorization is familiar in Indonesia since early childhood (EC) education level and it is reported to have a positive effect on children's emotional state. This study investigates how Quran memorization influences children's emotions in a certain condition using Frontal Alpha Asymmetry (FAA) index. Method : The participants were 4 children aged 5-7 years, studying at Islamic-based schools in Surakarta. The tasks included three methods of Quran learning: visual, by watching videos; auditory, by listening to murattal recitations of the Quran; and memory, by repeating rote. The FAA index measurement used absolute power data obtained from Electroencephalography (EEG) by calculating the natural logarithm (ln [right alpha power] - ln [left alpha power]) from channel F8 and channel F7 respectively. Results: The majority of participants showed a positive FAA index in almost all tasks. The FAA index of various tasks were not significantly different from each other, with P = 0.592 based on Kruskal-Wallis nonparametric test. The post hoc Mann-Whitney U test does not find any intervention that stands out among the others. Conclusion: Learning the Quran with methods that involve visual, auditory, and memory activities results in positive, happy, motivated and excited feelings in children's emotional state based on the FAA index assessment.

The Implementation of Peer-Reflection to Improve Retakers' Achievement in National Medical Students Examination.

INTRODUCTION: Faculty of medicine plays a role to support the students' success in passing national exit exam through mentorship. Peer-reflection evaluates the students' learning process. We aimed to analyze the impact of peer-reflection to change the students' learning attitude and improve national exam score. METHODS: Nine test-retaker students participated in mentorship program for three months. They took two parts of faculty-level examination. After the 1st and the 2nd part of faculty exam, there were peer-reflections I and II that argued about the characters, strengths and weaknesses, suggestions. Then, they did self-reflection to conduct responses about the mentorship including the impact of peers' input and finally took national exam. The examination score before and after peer-reflection were compared. We analyzed the statement of reflection by documents and content analysis. The progress of examination score was analyzed descriptively. RESULTS: The students objectively understood the strengths and weaknesses of their way of learning, and then implemented the peers' advices. Peer-reflection method provided a feeling of same purpose, then developed ways of learning that promoted them to be higher motivated. Finally, 6 of 9 students passed the exam. DISCUSSION: Suggestions given by peers would be memorable and powerfully changed motivation. Peer-reflection explored non-academic problems that determined the pattern and the way of how students learned.

Down-regulation of cobalt-induced HIF-1alpha expression correlates with cell proliferation and apoptosis in human gastric carcinoma cells.

Previously we reported that the hypoxia-inducible factor-1alpha (HIF-1alpha) expression correlated with cell proliferation and apoptosis under 500 mM of CoCl2 treatment in a human gastric carcinoma cell line, MKN-1. Herein we report a similar correlation in other cell lines, MKN-45 and TMK-1. The dual-phase expression of HIF-1alpha was highest at 6 and 8 h of treatment in MKN-45 and TMK-1, respectively, while the peak in MKN-1 occurred at 4 h. The cell viability indices showed a similar dual phase to the HIF-1alpha expression, while the apoptotic indices started to increase as the level of the HIF-1alpha expression decreased. In our previous study, the FACS analysis showed a marked G2/M arrest and an increase of the pre-G1 area in MKN-1 after 36 h of treatment, whereas the G2/M arrest was not observed in MKN-45 and TMK-1. The expression of cell cycle and apoptosis-related proteins showed a correlation with the HIF-1alpha expression and the FACS results, which suggested that the level of HIF-1alpha correlated with proliferation and apoptosis in human gastric carcinoma cell lines with a possible cell-type specific pattern.

CoCl2-induced HIF-1alpha expression correlates with proliferation and apoptosis in MKN-1 cells: a possible role for the PI3K/Akt pathway.

The exact mechanism behind the effect of hypoxia-inducible factor-1alpha (HIF-1alpha) on the proliferation and/or apoptosis of carcinoma cells is still a matter of debate. We treated a human gastric carcinoma cell line, MKN-1 (mutant P53), with 500 microM CoCl(2). A dual-phase pattern of HIF-1alpha expression with an increase until 4 h followed by a decrease until 36 h was observed. Immunocytochemistry showed that nuclear translocation was maximal at 4 h of treatment, while trypan blue staining showed a dual-phase pattern. Instead of G1/S arrest, FACS showed an increase in the pre-G1 fraction and G(2)/M arrest that correlated with Cyclin-B1, SKP-2 and P27 expression. Starting at 6 h, the apoptotic index increased in a time-dependent manner, in correlation with the expression of HIF-1alpha, Bcl-2, Bcl-xL, Bax and cleaved-Caspase-9. Phosphorylation of Akt was inhibited by CoCl(2) treatment and LY294002 treatment inhibited HIF-1alpha expression in a dose-dependent manner. These results suggested that the alteration of CoCl(2)-induced HIF-1alpha expression correlated with proliferation and apoptosis in MKN-1 cells. A possible role for the PI3K/Akt pathway was indicated in this model of hypoxia.

COX-2 inhibitor, NS398, enhances Fas-mediated apoptosis via modulation of the PTEN-Akt pathway in human gastric carcinoma cell lines.

A variety of human cancer cells are resistant to Fas ligand and anti-Fas antibody induced apoptosis. Previously, we reported that human gastric carcinoma cell lines were resistant to the anti-Fas antibody, CH-11, without interferon-gamma pretreatment in vitro. Cyclooxygenase (COX)-2 is known to be expressed in many human malignancies, and is correlated with tumor progression and resistance to apoptosis. This study examined whether NS398, a COX-2 inhibitor, inhibited cell proliferation and increased Fas-mediated apoptosis in human gastric carcinoma cell lines. Treatment of NS398 inhibited cell proliferation in MKN-45, which expressed the highest level of COX-2 among seven human gastric carcinoma cell lines, in a dose- and time-dependent manner, in contrast to less prominent effects in KATO-III, which expresses no COX-2. Although the treatment of CH-11 induced apoptosis in both cells, the simultaneous treatment of NS398 and CH-11 remarkably induced apoptosis, as confirmed by Hoechst 33258 staining and the terminal deoxynucleotidyl transferase- mediated dUTP-digoxigenin nick-end labeling (TUNEL) method in MKN-45. Flow cytometric analysis also revealed the increased pre-G1 fraction by the simultaneous treatment. The treatment of NS398 induced upregulation of Bad and PTEN, and downregulation of phosphorylated Akt (Thr308). These findings suggest that COX-2 might inhibit Fas-mediated apoptosis in human gastric carcinoma cell lines, especially MKN-45, by modulating PTEN and Akt.

COX-2 correlates with F-box protein, Skp2 expression and prognosis in human gastric carcinoma.

The expression of cyclooxygenase (COX)-2 is induced by growth factors, tumor promoters and cytokines, and is correlated with carcinogenesis, tumor progression and inhibition of apoptosis. To clarify the pathological significance of COX-2, we examined the effect of a selective COX-2 inhibitor, NS398, on two human gastric carcinoma cell lines, MKN-45 and KATO-III, and the expression of Skp2, P27/Kip1 and COX-2 protein in human gastric carcinomas. NS398 inhibited cell growth in a time- and dose-dependent manner and exerted cell cycle arrest in the G0/G1 phase without induction of apoptosis in MKN-45, but had no effect in KATO-III. In MKN-45, NS398 induced up-regulation of P27/Kip1 and down-regulation of COX-2, cyclin D1 and Skp2. Immunohistochemistry using 63 surgically resected gastric carcinomas disclosed that COX-2 expression was correlated with Skp2 expression and that P27/Kip1 expression was inversely correlated with COX-2 and Skp2 expression. High levels of COX-2 or Skp2 were significantly correlated with poor survival (P=0.02 and P=0.004). Our results suggested that: a) NS398 induced inhibition of cell proliferation through cell cycle arrest and suppressed the expression of Skp2 in COX-2-expressing gastric carcinoma cells, and b) COX-2 contributes to the expression of Skp2 and poor survival in human gastric carcinomas.

Cyclooxygenase-2 in human malignant fibrous histiocytoma: correlations with intratumoral microvessel density, expression of vascular endothelial growth factor and thymidine phosphorylase.

Cyclooxygenase-2 (COX-2) has been found to be up-regulated in several types of human malignant tumors and proposed to have a role in the angiogenic process. This study examined the expression of COX-2 in two human malignant fibrous histiocytoma (MFH) cell lines by Western blotting, which showed a specific single band at 72 kDa. Immunohistochemistry was conducted in 35 MFHs and 30 benign fibrohistiocytic tumors (BFHTs), comparing the expression of vascular endothelial growth factor (VEGF) and thymidine phosphorylase (TP), as well as intratumoral microvessel density (IMVD). COX-2 expression was noted in 22 (62.9%) MFHs, but in no BFHT. IMVD values were significantly higher in the MFHs (90.6+/-8.0) than BFHTs (27.9+/-3.1), and also in the COX-2 positive (104.5+/-11.3) than negative (67.2+/-5.8) MFHs. VEGF and TP expression was also associated with a significantly higher level of COX-2, as well as greater IMVD. The highest IMVD values were noted in the 17 MFHs (120.8+/-11.5) expressing all three factors. Clinical analysis demonstrated poorer survival in the 18 COX-2 positive MFHs than in the 10 negative ones, although the small number of cases did not reveal a significant difference. The results overall indicated that COX-2 expression is associated with intratumoral angiogenesis, which might provide favorable conditions for tumor progression in human MFHs.

Cyclooxygenase-2 expression in human gastric tubular adenomas and carcinomas; correlation with intratumoral microvessel density and apoptotic index.

BACKGROUND: Cyclooxygenase (COX)-2 plays an important role in carcinogenesis in various human malignancies. This study examined the relationship among COX-2 expression, angiogenesis and apoptosis in human gastric adenoma and carcinoma. MATERIALS AND METHODS: We examined the expression of COX-2 in 30 tubular adenomas and 11 carcinomas, comparing it with intratumoral microvessel density (IMVD) and apoptotic index (AI) by immunohistochemistry and the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-digoxygenin nick-end labeling (TUNEL) procedure. RESULTS: Immunohistochemistry demonstrated positive expression of COX-2 in 15 (50.0%) adenomas and in 50 (53.1%) carcinomas, respectively. The frequency of COX-2 expression was significantly higher in intestinal-type carcinomas than in diffuse-type, regardless of the tumor stage. The IMVD was significantly higher in the early and advanced carcinomas than in the adenomas and also higher in the COX-2-positive adenomas and carcinomas than in the negative ones. The AI was significantly higher in the adenomas than in the carcinomas and also in the COX-2-negative adenomas and intestinal-type early carcinomas than in their positive counterparts, respectively (p < 0.05). The IMVD and AI showed significant inverse correlation in both the adenomas (p=0.02, r=-0.64) and carcinomas (p=0.04, r=-0.18). CONCLUSION: COX-2 expression might be an early event in gastric tumorigenesis and provide a preferential advantage for tumor cell proliferation because of its vascular-rich microenvironment and escape from tumor cell apoptosis, especially in intestinal-type gastric carcinomas.

Co-expression of Cox-2 and EGFR in stage I human bronchial adenocarcinomas.

Cyclooxygenase (Cox)-2 plays an important role in cell proliferation, carcinogenesis and tumor growth, in part through the synthesis of prostaglandin E2 (PGE2) as well as through other yet unknown routes. Epidermal growth factor receptor (EGFR) signaling regulates Cox-2 expression, which has not been thoroughly examined in bronchial carcinomas. The current study examined the expression of Cox-2, EGFR, P53 and proliferative marker Ki-67 immunoreactivities by immunohistochemistry in 71 surgically removed stage I bronchial adenocarcinomas. Furthermore, we evaluated the prognostic value of these molecules to elucidate the biological significance of Cox-2 expression. Higher Cox-2 expression (more than 10% immunoreactivities in tumor cells) was strongly associated with higher EGFR and P53 expression as well as a Ki-67 LI above 20% (P < 0.01). Cox-2 and EGFR immunoreactive tumor cells showed a similar distribution pattern. Five-year survival rate was 73% in 57 cases showing higher Cox-2 expression and 100% in 14 cases showing lower expression, indicating a significant difference in survival (P = 0.040). Higher Cox-2 expression might be associated with tumor progression and worse prognosis through EGFR signaling interaction in Stage I bronchial adenocarcinomas.