A novel oxiranylchromenone derivative, MHY336, induces apoptosis and cell cycle arrest via a p53- and p21-dependent pathway in HCT116 human colon cancer cells.

In this study, we compared cytotoxicity, cell cycle distribution, and apoptosis on MHY336 treatment in three human colorectal carcinoma HCT116 cells: p53+/+ (p53‑wt), p53-/- (p53-null), and p21-/- (p21-null), as well as investigated the roles of p53 and p21 in cell death. Using these three isogenic variants, the roles of p53 and p21 in the cellular response to treatment with MHY336, a novel topoisomerase IIα inhibitor, were investigated. Our results showed that MHY336 treatment increased the expression of p53 over time in cells with wild-type p53 status.

Adaptive redundant speech transmission over wireless multimedia sensor networks based on estimation of perceived speech quality.

An adaptive redundant speech transmission (ARST) approach to improve the perceived speech quality (PSQ) of speech streaming applications over wireless multimedia sensor networks (WMSNs) is proposed in this paper. The proposed approach estimates the PSQ as well as the packet loss rate (PLR) from the received speech data. Subsequently, it decides whether the transmission of redundant speech data (RSD) is required in order to assist a speech decoder to reconstruct lost speech signals for high PLRs.

Design, synthesis and anticancer activity of novel dihydrobenzofuro[4,5-b][1,8]naphthyridin-6-one derivatives.

On the basis of the chemical structures of psorospermin with a xanthone template and acronycine derivatives with an acridone template, rac-1 and rac-2 constructed on an 1,2-dihydrobenzofuro[4,5-b][1,8]naphthyridin-6(11H)-one scaffold were designed and synthesized as potential anticancer agents. Their anticancer activities were evaluated against five human cancer cell lines. Rac-2 showed similar anticancer activity to doxorubicin and rac-1 exhibited even higher anticancer activity against LNCaP (IC(50)=0.

Synthesis of enantiomerically pure D- and L-bicyclo[3.1.0]hexenyl carbanucleosides and their antiviral evaluation.

Based upon the fact that L-nucleosides have been generally known to be less cytotoxic than D-counterparts, L-bicyclo[3.1.0]hexenyl carbanucleoside derivatives with a fixed north conformation were designed and synthesized by employing a novel synthetic strategy starting from (R)-epichlorohydrin in order to search for new anti-HIV agents with high potency and less cytotoxicity.

A novel epoxypropoxy flavonoid derivative and topoisomerase II inhibitor, MHY336, induces apoptosis in prostate cancer cells.

Here, we reported the synthesis of a novel topoisomerase II inhibitor, MHY336, which that has strong topoisomerase-mediated anticancer activity but fewer side effects than other topoisomerase II inhibitors. The catalytic activity of MHY336 on the topoisomerase II enzyme was the same as that of the etoposide. In a cell-free system, MHY336 exhibited a potent activity on scavenging of reactive oxygen species against 3-morpholinosydnonimine hydrochloride (SIN-1)-induced oxidative stress.

Isolated cerebrospinal fluid leakage due to a spinal stab wound in a child.

Spinal stab wounds are relatively rare, especially in children. Moreover, as the pediatric spine anatomy differs from that of an adult, physicians managing stab wounds in this area should keep some special considerations in mind. This study reports an interesting case of spinal cerebrospinal fluid leakage without significant spinal injury in a 32-month-old child.

Efficient and practical synthesis of L-hamamelose.

An efficient synthetic route of L-hamamelose was successfully accomplished starting from D-ribose. L-Hamamelose was synthesized in 42% overall yield with six reaction steps via a stereoselective Grignard reaction, a stereoselective crossed aldol reaction and a controlled oxidative cleavage of the double bond of a vinyl diol compound. During the oxidative cleavage of the double bond of the vinyl diol compound with osmium tetroxide and NaIO(4), an over-oxidative cleavage of alpha-hydroxyl aldehyde generated from ring opening of the first cleaved product, formyl lactol, did not occur, probably due to the stability of the lactol form.

Synthesis and biological evaluation of 5''-iodoneplanocin A and its analogues.

5''-Iodoneplanocin A was enantiopurely synthesized as potential antiviral and antitumor agents starting from D-ribose using an addition-iodination-elimination reaction, a RCM reaction and an oxidative rearrangement.

Synthesis and antiviral evaluation of conformationally fixed bicyclohexanyl nucleosides with ethenyl group at C3'-position.

Conformationally fixed bicyclo[3.1.0]hexanyl nucleosides 1 and 2 with C3'-ethenyl group were successfully synthesized and evaluated against various viruses.

Synthesis of novel cyclopropyl nucleoside analogues as potential antiherpetic agent.

Synthesis of novel cyclopropyl pyrimidine and purine nucleoside derivatives was successfully achieved using one pot reactions including an alkylation, an oxirane-ring opening reaction and a lactonization and a hydroboration-oxidation as the key steps in order to find new antiherpetic agent.

Synthesis of pyrimidine analog of fluoroneplanocin A as potential anti-HCV agent.

N-hydroxycytosine nucleoside 3 was synthesized as potential anti-HCV agent, starting from D-ribose using an iodine-fluorine exchange reaction by a help of BuLi, a RCM reaction, a stereoselective reduction and a Mitsunobu reaction as the key steps.

Asymmetric synthesis of apio fluoroneplanocin A analogs as potential AdoHcy hydrolase inhibitor.

Apio fluoroneplanocin A (apio F-NPA, 3) and its uracil analogue 4 have been designed and asymmetrically synthesized starting from D-ribose. Introduction of fluoro group into vinylic position of 5 was accomplished successfully over 5 steps employing key reactions such as iodination according to an addition-elimination reaction mechanism, stereo- and regioselective reduction of alpha,beta-unsaturated ketone, and electrophilic fluorination. This methodology can be adapted to the synthesis of fluoro compounds extensively.