TASK DEFINITION: Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
PROBLEM: The inducible nitric oxide synthase (iNOS) is associated with inflammatory processes and cancer formation through production of nitric oxide (NO). However, the clinical importance of the expression of iNOS in oral cancer remains unclear. In the present study, we examined whether up-regulation of the iNOS gene can affect growth and metastasis of an oral cancer cell line (B88t cell) in vitro and in vivo.', 'We constructed an expression vector containing sense-oriented murine iNOS cDNA with pcDNA3.1. We transfected B88t cells with the sense expression vector to up-regulate the expression of the iNOS gene in the sense transfectants.', 'The expression of iNOS protein was up-regulated in the sense transfectants and that up-regulation of the iNOS gene exerted a growth inhibitory effect on B88t cells in vitro and in vivo. Moreover, up-regulation of the iNOS gene markedly inhibited the migration of cancer cells in a Boyden chamber. Furthermore, up-regulation of the iNOS gene dramatically inhibited metastases to the cervical lymph node in vivo.

SOLUTION: Does overexpression of iNOS gene suppress the tumorigenicity and metastasis of oral cancer cells?

PROBLEM: The biliary cast syndrome (BCS) is a frequent problem following liver transplantation. The pathogenesis of this complication is not well understood. Previous research has demonstrated that the soluble form of MICA (sMICA) is significantly higher in patients with chronic liver disease and hepatocellular carcinoma (HCC) than in healthy volunteers. The aim of this study is to investigate the possible involvement of sMICA in the formation of BCS after liver transplantation.', 'Serum soluble MICA was retrospectively evaluated in pre- and post-transplant sera from 133 consecutive primary liver transplant patients and in sera from 88 healthy volunteers using sandwich ELISA. Normal distribution of serum sMICA was described by the data obtained from healthy population and sMICA concentration that was greater than the upper bound 95% normal range was considered as high levels of sMICA. Patient records were reviewed to identify patients who developed BCS.', 'The results demonstrated that 37.6% of patients with end-stage liver diseases had significantly higher pre-transplant serum sMICA than in healthy population. 34.4% of recipients with post-transplant high levels of sMICA developed BCS. In contrast, 17.3% of patients with post-transplant normal levels of sMICA developed BCS. The risk of BCS development is significantly associated with the presence of post-transplant high levels of sMICA (P=0.0365). Further analysis disclosed that patients with decreased post-transplant sMICA following liver transplantation had a lower incidence rate of BCS than those with remained high levels of sMICA after transplantation (10.5% vs. 38.7%, P=0.0302). Furthermore, log-rank test showed that BCS occurrence was significantly associated with dynamic changes of sMICA among different groups (P=0.0188).

SOLUTION: Are high levels of soluble Major Histocompatibility Complex class I related chain A ( MICA ) associated with biliary cast syndrome after liver transplantation?

PROBLEM: Our previous studies suggested that brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) axis inhibited cardiomyocyte apoptosis in myocardial infarction (MI). However, the relationship between BDNF and microRNA (miRNA) in cardiomyocytes are unclear. The present study was performed to investigate the role of miR-195 and the interplay between BDNF and miR-195 in ischemic cardiomyocyte apoptosis.', 'Male Wistar rats were subjected to coronary artery ligation, and primary neonatal rat ventricular myocytes were treated with hypoxia or hydrogen peroxide (H2O2). BDNF level in rat ventricles was measured by enzyme linked immunosorbent assay (ELISA). miR-195 mimic, inhibitor or negative control was transfected into the cardiomyocytes. Cell viability and apoptosis were detected by MTT assay and TdT-mediated dUTP nick end labeling (TUNEL) staining, respectively. Cardiac function and apoptosis were detected in MI rats intravenously injected with antagomiR-195. Luciferase assay, Western blot and Real-time RT-PCR were employed to clarify the interplay between miR-195 and BDNF.', 'miR-195 level was dynamically regulated in response to MI and significantly increased in ischemic regions 24 h post-MI as well as in hypoxic or H2O2-treated cardiomyocytes. Meanwhile, BDNF protein level was rapidly increased in MI rats and H2O2-treated cardiomyocytes. Apoptosis in both hypoxic and H2O2-treated cardiomyocytes were markedly reduced and cell viability was increased by miR-195 inhibitor. Moreover, inhibition of miR-195 significantly improved cardiac function of MI rats. Bcl-2 but not BDNF was validated as the direct target of miR-195. Furthermore, BDNF abolished the pro-apoptotic role of miR-195, which was reversed by its scavenger TrkB-Fc.

SOLUTION:
Does bDNF-mediates Down-regulation of MicroRNA-195 inhibit Ischemic Cardiac Apoptosis in Rats?