Earticle

Marine ecosystems are often characterized by a high biological diversity, and it corresponds to a high chemical diversity. Up to present, more than 20,000 new bioactive substances have been isolated from marine organisms, where considerable numbers of these naturally occurring derivatives are developed as potential candidates for pharmaceutical application. In this process, screening of natural products from marine organisms that could potentially inhibit the expression of metalloproteinases has gained a huge popularity. Cancer is considered as one of the deadliest diseases in the medical field. Matrix metalloproteinase (MMPs) can degrade extracellular matrix (ECM) components and play important roles in a variety of biological and pathological processes. Matrix metalloproteinase inhibitors (MMPIs) have been identified as potential therapeutic candidates for metastasis, arthritis, chronic inflammation and wrinkle formation.

Focal adhesion kinase (FAK) is a potential target for the treatment of primary cancers as well as prevention of tumor metastasis. To understand the structural and chemical features of FAK inhibitors, we report comparative molecular field analysis (CoMFA) for the series of 7H-pyrrolo(2,3-d)pyrimidines. The CoMFA models showed good correlation between the actual and predicted values for training set molecules. Our results indicated the ligand-based alignment has produced better statistical results for CoMFA (q2 = 0.505, r2 = 0.950). Both models were validated using test set compounds, and gave good predictive values of 0.537. The statistical parameters from the generated 3D-QSAR models were indicated that the data are well fitted and have high predictive ability. The contour map from 3D-QSAR models explains nicely the structure–activity relationships of FAK inhibitors and our results would give proper guidelines to further enhance the activity of novel inhibitors.

It’s a threat for the public health that H1N1 (Influenza virus A) causes disease and transmits among humans. WHO (world health organization) declared that the infections caused by the new strain had reached pandemic proportions. The approved neuraminidase inhibitors (Zanamivir and Oseltamivir) and related investigative drug (BCX-1812) are potent, specific inhibitors of influenza A and B viruses. These drugs are highly effective to prevent influenza A and B infections. Early therapeutic use reduces illness duration and respiratory complications. Recently, we found one of the potent inhibitor of erystagallin A (IC50 of 2.04 μM) for neuraminidase target, this inhibitor shows most similar structure to its natural substrate, sialic acid. Therefore, we chose 1l7f to get the receptor structure for docking study among many crystal structures. A docking study has been performed in Surflex-Dock module in SYBYL 8.1. In the present study, we attempt to compare the docking studies of pterocarpin and erystagallin A with neuraminidase receptor structure. In the previous report, the methoxy group of pterocarpin had H-bonding with Arg residues. The present docking results for erystagallin A showed the backbone of hydroxyl group shows significant H-bonding interactions with Arg152 and Arg292. The results showed that erystagallin A interacts more favorably with distinctive binding site rather than original active site. Therefore, we tried to reveal plausible binding mode and important amino acid for this inhibitor using docking and site id search calculations of Sybyl. The results obtained from this work may be utilized to design novel inhibitors for neuraminidase.

We discuss an application of ‘restrictions on the entries of the maps in the minimal free resolution‘ and ‘SCr-condition of modules’, and give an alternative proof of the following result of Foxby: Let M be a finitely generated module of dimension over a Noetherian local ring (A,m). Suppose that has no embedded primes. If A is not Gorenstein, then μi(m,A) ≥ 2 for all i ≥ dimA.

We describe the synthesis and characterization of silicon nanoparticles prepared by the solution reduction of silicon tetrachloride by lithium naphthalenide and subsequently with n-butyllithium at room temperature. These reactions produce silicon nanoparticles with surfaces that are covalently terminated with butyl group. Reaction with lithium aluminium hydride instead of n-butyllithium produces hydride-terminated silicon nanoparticles. The butyl or hydride terminated silicon nanoparticles can be suspended in hexane and their optical behavior have been characterized by photoluminescence spectroscopy. Stabilization of silicon nanoparticles were investigated upon illumination, indicating that as-prepared silicon nanoparticles are very stable at room temperature for several days.

In this paper we obtain some Sobolev estimates for the integral operator over singular curves (t, tm) on R2 for m ≥ 2.

Quality of PEDOT electrode thin film vapor phase-polymerized on 3- aminopropyltriethoxysilane (APS) self-assembled monolayer (SAM) is very crucial for making an ohmic contact between electrode and semiconductor layer of an organic transistor. In order to improve the quality of PEDOT film, the quality of APS- SAM laying underneath the film must be in the best condition. In this study, in order to improve the quality of APS-SAM, the monolayer was self-assembled on SiO2 surface by a dip-coating method under strictly controlled relative humidity (< 18%RH). The quality of APS-SAM and PEDOT thin film were investigated with a contact angle analyzer, AFM, FE-SEM, and four-point probe. The investigation showed that a PEDOT film grown on the humidity-controlled SAM is very smooth and compact (sheet resistivity = 20.2 Ohm/sq) while a film grown under the uncontrolled condition is nearly amorphous and contains quite many pores (sheet resistivity = 200 Ohm/sq). Therefore, this study clearly proves that a highly improved quality of APSSAM can offer a highly conductive PEDOT electrode thin film on it.

Application of self-assembled monolayers (SAMs) to the fabrication of organic thin film transistor has been recently reported very often since it can help to provide ohmic contact between films as well as to form simple and effective electrode pattern. Accordingly, quality of these ultra-thin films is becoming more imperative. In this study, in order to manufacture a high quality SAM pattern, a hydrophobic alkylsilane monolayer and a hydrophilic aminosilane monolayer were selectively coated on SiO2 surface through the consecutive procedures of a micro-contact printing (μCP) and dipcoating methods under extremely dry condition. On a SAM pattern cleaned with SC1 solution immediately after μCP, poly(3,4-ethylenedioxythiophene) (PEDOT) source and drain electrode array were very selectively and nicely vapour phase polymerized. On the other side, on a SC1-untreated SAM pattern, PEDOT array was very poorly polymerized. It strongly suggests that the SC1 cleaning process effectively removes unwanted contaminants on SAM pattern, thereby resulting in very selective growth of PEDOT electrode pattern.

This study was performed to investigate the current regulatory guidances of safety and efficacy evaluation for the approval of stereoisomeric drugs in Korea and US. According to the regulatory guidelines in major countries (EU, Canada, US), the important categories for the development of stereoisomeric drugs are classified as 1) development of a single enantiomer as a new active substances 2) development of a racemate as a new active substance 3) development of a new single enantiomer from an approved racemate. For this study, domestic regulatory documents for current guidelines of stereoisomeric drugs were investigated. Also four typical stereoisomeric drugs for three categories were chosen to investigate the new drug submission documents of KFDA and FDA for the safety and efficacy evaluation of stereoisomeric drugs. It is expected that these comparative results between KFDA and FDA will be useful for the safety and efficacy for the regulatory approval of stereoisomeric drugs in Korea.

In this study, α-chlorosuccinic acid was synthesized through the reaction of maleic anhydride with HCl(g), (UV)250 nm~300 nm wavelength in presence of CCl4. For the second reaction of N-(monochloro)succinic acid contained glucosamine derivatives(I) was accomplished by a modification of the general acylation using excess α-chlorosuccinic anhydride in the presence of 2% acetic acid with methanol condition as a solvent at elevated temperature(70oC). We considered organic acid derivatives were useful especially for treatment for the cultivating porphyra.

This study was conducted to find associations of stress with obesity in female college students in Gwangju. 343 subjects were divided into two groups based on BMI(body mass index). BMI of normal group was 19.3±1.5 while that of obese group was 26.4±3.6. The measured stress level in obese subjects was higher and they were less capable of controlling obese oriented attitude compared to normal subject. Twenty four hour dietary recall revealed that nutrient intakes of obese subjects were higher in energy, lipid, P and cholesterol. However, they were more deficient in Ca, Fe and vitamin A, compared to those of normal ones. This study suggested severe stress might trigger undesirable dietary behavior leading to increase in food consumption which contribute to obesity. Effective nutrition education program targeting obese female students should be developed and implemented to relieve stress and practice desirable dietary behavior and eating pattern.