Micro RNA-518 inhibits gastric cancer cell growth by inducing apoptosis via targeting MDM2.

Gastric cancer is a most common malignancy and the third leading cause of cancer mortality worldwide. So it is important to identify the prognostic markers and effective therapeutic targets against gastric cancer. miRNA plays an important role in tumor cell cycle, differentiation, apoptosis, invasion and metastasis. Many studies devote to the mechanism of miRNA regulates gastric cancer carcinoma and progression. In the present study, we found that the level of miR-518 in gastric cancer and cell lines were lower than the control or the adjacent tissues by qRT-PCR. Transfected with miR-518 mimic trigger apoptosis in MKN45 and HGC27 gastric cancer cell in vitro and in vivo. Moreover, we found that MDM2 was negatively regulated by miR-518 via targeting 26-32 site of 3'UTR using luciferase reporter assay. The western blot assay showed that miR-518 up-regulated the expression of p53, pro-apoptotic protein Bax and active the activity of cleaved caspase-3, down-regulated expression of anti-apoptotic protein Bcl-2 via targeting MDM2. Thus, our study suggested that miR-518 acted as a new tumor suppressor by targeting MDM2 gene and trigger apoptosis in vivo and in vitro. The findings of the study first established the role of miR-518 in gastric cancer and may be a potential therapeutic target against gastric cancer in the further.

[Topological models of retention index of thin-layer chromatogram for chiral organic acids].

On the basis of Kier's molecular connectivity indices and conjugated matrix, novel molecular connectivity indices ((m) G(t)(v)) were defined and calculated for 18 chiral hydroxyl acids and amino acids. The chiral connectivity indices ((m)C(t)(v)) were introduced by extending (m)G(t)(v): (m)C(t)(v) = (m)G(t)(v) x w(j), where w(j) is the chiral index. The quantitative structure-retention index relationship (QSRR) between the retention index (R(M)) of thin-layer chromatogram for the chiral organic acids and (m)C(t)(v) was studied by multivariate statistical regression. By leaps-and-bounds regression analysis, the best four-parameter QSRR model was set up, and the traditional correlation coefficient (R2) and the cross-validation correlation coefficient (Q2) of leave-one-out (LOO) were 0.973 and 0.950, respectively. The results demonstrated that the model was highly reliable and had good predictive ability from the point of view of statistics. From the four parameters (0C(p)(v), 2C(p)(v), C(ch),(v), 5C(p)(v)) of the model, it is known that the dominant influence factors of the retention index were the molecular structure characteristics of two-dimensional and the space factors: the chiral characteristics, the flexibility and the puckered degree of molecules for the chiral organic acids. The results showed that the new parameter mC(t)(v) had good rationality and efficiency for the retention indices of the chiral organic acids. Therefore, an effective method was provided to predict the retention indices of the chiral organic acids.

2-(2-Chloro-phen-yl)-2,3-dihydro-quinazolin-4(1H)-one.

The title compound, C(14)H(11)ClN(2)O, was synthesized by the reaction of 2-chloro-benzaldehyde and 2-amino-benzamide in an ionic liquid. The pyrimidine ring adopts a skew-boat conformation and the two benzene rings make a dihedral angle of 87.1 (1)°. In the crystal, N-H⋯O and C-H⋯N hydrogen bonding links the mol-ecules along b.

Topological research on diamagnetic susceptibilities of organic compounds.

A novel molecular connectivity index, (m)chi('), based on the adjacency matrix of molecular graphs and novel atomic valence connectivities, delta(i)(') for predicting the molar diamagnetic susceptibilities of organic compounds is proposed. The delta(i)(') is defined as: delta(i)(') = delta(i)(nu) x Ei=12:625, where delta(i)(nu) and E(i) are the atomic valence connectivity and the valence orbital energy of atom i, respectively. A good QSPR model for molar diamagnetic susceptibilities can be constructed from (0)chi('), (1)chi('), (2)chi(') and (4)chi(p)(') using multivariate linear regression (MLR). The correlation coefficient r, standard error, and average absolute deviation of the MLR model are 0.9918, 5.56 cgs, and 4.26 cgs, respectively, for the 721 organic compounds tested (training set). Cross-validation using the leave-one-out method demonstrates that the MLR model is highly reliable statistically. Using the MLR model, the average absolute deviations of the predicted values of molar diamagnetic susceptibility of another 360 organic compounds (test set) is 4.34 cgs. The results show that the current method is more effective than literature methods for estimating the molar diamagnetic susceptibility of an organic compound. The MLR method thus provides an acceptable model for the prediction of molar diamagnetic susceptibilities of organic compounds.

[Detecting the haplotype of three Y-STR loci by fluorescent multiplex amplification].

OBJECTIVE: To establish a fluorescent multiplex PCR system for typing Y-STR loci Y-GATA-A7.1, DYS456 and DYS443, and investigate their haplotype frequencies in Chinese Han population. METHODS: 203 unrelated males of Han population living in Zhengzhou were typed by fluorescent multiplex amplification system and ABI 3100 genetic analyzer. RESULTS: In Zhengzhou Han population, 5,6 and 6 different alleles were observed for Y-GATA-A7.1, DYS456 and DYS443 loci, and their gene diversity (GD) were 0.669 2, 0.583 9 and 0.705 3 respectively. A total of 44 different haplotypes formed by these three loci was identified and the haplotype diversity (HD) reached 0.952 3. CONCLUSION: The fluorescent multiplex system for these three Y-STR loci will be very powerful for forensic individual identification and paternity testing in Chinese Han population.

[Correlation analysis of structures and gas chromatographic retention indices of aliphatic alcohols].

A characteristic value of atom i is defined as A(i) = (delta(i)v + sigma n(ij)v)/(1 + sigma n(ij)). Based on the adjacency matrix, an average valence connectivity index is set up by A(i) as (m)L = sigma (A(i), x A(j) x A(k)...)(-0.5). The first topological index (1)L among (m)L is defined as (1)L = sigma (A(i) A(j))(-0.5). Then (1)L of aliphatic alcohols were calculated. (1)L has good structural selectivity. (1)L and orientating group parameter (beta) have high correlativity with the gas chromatographic retention indices of 25 aliphatic alcohols on six different stationary phases (SE-30, OV-3, OV-7, OV-11, OV-17 and OV-25). A general linear regression equation is proposed as follows: I = a + b (1)L + cbeta, where I stands for the gas chromatographic retention index, a, b and c are regression coefficients. All the correlation coefficients were larger than 0.98. These models can better elucidate the change rule of the gas chromatographic retention indices for aliphatic alcohols. Moreover, using this model, the gas chromatographic retention indices of ten aliphatic alcohols have been predicted, and the results are quite satisfactory. It has been demonstrated that the quantitative structure-retention relationship (QSRR) models have good stability and predictability.