Substituent-regulated highly X-ray sensitive Os(Ⅵ)nitrido complex for low-toxicity radiotherapy

A high efficiency and low toxicity radiosensitizer,OsN(PhenOH)Cl_3,was designed and synthesized through substituent regulation.To the best of our knowledge,this is the first osmium-based coordination complex radiosensitizer.The experimental results shown that this radiosensitizer induced G2/M cell cycle arrest mainly through induction of intracellular ROS overproduction.     

A generalization of Heffter arrays

In this paper, we define a new class of partially filled arrays, called relative Heffter arrays, that are a generalization of the Heffter arrays introduced by Archdeacon in 2015. Let $v=2nk+t$ be a positive integer, where $t$ divides $2nk$, and let $J$ be the subgroup of ${\mathbb{Z}}_v$ of order $t$. A ${\mathrm{H}}_t\left(m,n;s,k\right)$ Heffter array over ${\mathbb{Z}}_v$ relative to $J$ is an $m\times n$ partially filled array with elements in ${\mathbb{Z}}_v$ such that (a) each row contains $s$ filled cells and each column contains $k$ filled cells; (b) for every $x\in {\mathbb{Z}}_v\backslash J$, either $x$ or $?x$ appears in the array; and (c) the elements in every row and column sum to $0$. Here we study the existence of square integer (i.e., with entries chosen in $\pm \left\{1,\text{…},?\frac{2nk+t}{2}?\right\}$ and where the sums are zero in $\mathbb{Z}$) relative Heffter arrays for $t=k$, denoted by ${\mathrm{H}}_k\left(n;k\right)$. In particular, we prove that for $3\le k\le n$, with $k\ne 5$, there exists an integer ${\mathrm{H}}_k\left(n;k\right)$ if and only if one of the following holds: (a) $k$ is odd and $n\equiv 0,3\left(\text{mod}4\right)$; (b) $k\equiv 2\left(\text{mod}4\right)$ and $n$ is even; (c) $k\equiv 0\left(\text{mod}4\right)$. Also, we show how these arrays give rise to cyclic cycle decompositions of the complete multipartite graph.     

Rhododendron molle G. Don Extract Induces Apoptosis and Inhibits Migration in Human Colorectal Cancer Cells and Potential Anticancer Components Analysis

Rhododendron molle G. Don is one example of traditional Chinese medicine with important medicinal value. In this study, the effects of methanol extract of R. molle leaves (RLE) on colorectal cancer HT-29 cells and its potential molecular mechanism were investigated. MTT analysis showed that RLE could significantly inhibit the cell viability and migration of HT-29 cells in a concentration-dependent manner. Cell cycle analyses via flow cytometer suggested that RLE induced DNA fragmentation, indicative of apoptosis, and arrest at the S phase in HT-29 cells. Quantitative real-time PCR (qRT-PCR) analysis showed that RLE could upregulate the mRNA expression of p53 and p21 in HT-29 cells, which would result in HT-29 cells being blocked in S phase. Meanwhile, RLE could upregulate the expression of Bax, and downregulate the expression of Bcl-2, which would induce cell apoptosis. Further western blot analysis showed that the protein expression changes of Bax and P53 were basically consistent with the results of qRT-PCR. In addition, GC-MS analysis detected 17 potential anticancer components in R. molle. These results indicate that R. molle has significant anticancer activity, which provides some useful information for further study and clinical application for R. molle.     

Synthesis,structure, characterization and biological evaluation of 3‐substituted 1‐pyridin‐2‐ylimidazo[1,5‐a]pyridine‐based copper(I)–phosphine complexes for anticancer drug screening

Copper(I) complexes of the types [Cu(N–N)(PPh₃)₂]NO₃ (LC41–LC44) and [Cu(N–N)(PPh₃)(NO₃)] (LC45) carrying 3‐substituted 1‐pyridine‐2‐ylimidazo[1,5‐a]pyridine (N–N) derivatives and triphenylphosphine (PPh₃) ligands have been prepared. The synthesized copper(I)–phosphine complexes were fully characterized by NMR, IR, ESI‐MS and UV–visible spectroscopy as well as by cyclic voltammetry. Selected structures such as LC42, LC43 and LC45 were additionally analysed by single‐crystal X‐ray method, which show that copper(I) centre adopts a highly distorted tetrahedral geometry. The ¹H and ¹³C NMR spectral data of the complexes throw light on the nature of metal–ligand bonding. They display dπ–π* metal‐to‐ligand charge transfer (MLCT) transition and show quasireversible Cu^I/Cu^II metal oxidation. Among the copper(I)–phosphine complexes, LC41–LC44 exhibit moderate cytotoxicity (IC₅₀: 24 h, 67–74 μM; 48 h, 58–70 μM) against human lung epithelial adenocarcinoma A549 cells, whereas LC45 displays the best activity (IC₅₀: 24 h, 42 μM; 48 h, 34 μM) for A549 cancer cell line, which is better than that of the commercial antitumor drug cisplatin. All the complexes also displayed excellent selectivity by being relatively inactive against the human lung epithelial L132 normal cell line with selectivity index (SI) values ranging from 3.4 to 7.4. The complexes block cell cycle progression of A549 cells in G₀/G₁ phase. FACSVerse analyses are suggestive of reactive oxygen species (ROS) generation and apoptotic cell death induced by the LC41, LC43 and LC45. The induction of apoptosis in A549 cells was shown by Annexin V with propidium iodide (PI) and 4′,6‐diamidino‐2‐phenylindole (DAPI) staining methods and established the ability of LC41, LC43 and LC45 to accumulate in the cell nuclei.     

The Significant Influence of a Second Metal on the Antiproliferative Properties of the Complex [Ru(η6−C10H14)(Cl2)(dmoPTA)]

Complexes [Ru(η⁶−C₁₀H₁₄)(Cl₂)(HdmoPTA)](OSO₂CF₃) ( 1 ), [Ru(η⁶−C₁₀H₁₄)(Cl₂)(dmoPTA)] ( 2 ) and [Ru(η⁶−C₁₀H₁₄)(Cl₂)-μ-dmoPTA-1κP:2κ²N,N’-MCl₂] (M=Zn ( 3 ), Co ( 4 ), Ni ( 5 ), dmoPTA=3,7-dimethyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane) have been synthesized and characterized by elemental analysis and spectroscopic techniques. The crystal structures of 1 , 3 and 5 were obtained by single-crystal X-ray diffraction. The antiproliferative activity of the complexes was evaluated against colon cancer cell line Caco-2/TC7 by using the MTT protocol. The monometallic ruthenium complexes 1 and 2 were found to be inactive, but the bimetallic complexes 3 , 4 and 5 display an increased activity (IC₅₀ 3 : 9.07±0.27, 4 : 5.40±0.19, 5 : 7.15±0.30 μM) compared to cisplatin (IC₅₀=45.6±8.08 μM). Importantly, no reduction in normal cell viability was observed in the presence of the complexes. Experiments targeted to obtain information on the possible action mechanism of the complexes, such as cell cycle, ROS and gene expression studies, were performed. The results showed that the complexes display different properties and action mechanism depending on the nature of metal, M, bonded to the CH₃N_dmoPTA atoms.     

Convergence theorems for adapted sequences of random sets

We consider random sets with values in a separable Banach space. We study set-valued amarts, L¹-amarts, uniform amarts and submartingales. For all these classes of random sets, we prove convergence theorems in all main modes of set convergence (weak, Wijsman, Mosco, and Hausdorff). We also prove new convergence theorems for vector-valued subpramarts and pramarts.     

交叉口信号灯实时动态时间分配模型

从合理有效利用信号灯来减小滞留车辆数的角度出发提出了对信号灯时间实时动态分配模型，并以作者所在的武汉市街道口为试点，通过与传统最好的固定分配模型进行比较，结果发现，采用该模型对减少路口滞留车辆有了明显改观。     

On estimation in multivariate linear calibration with elliptical errors

The estimation problem in multivariate linear calibration with elliptical errors is considered under a loss function which can be derived from the Kullback-Leibler distance. First, we discuss the problem under normal errors and give unbiased estimate of risk of an alternative estimator by means of the Stein and Stein-Haff identities for multivariate normal distribution. From the unbiased estimate of risk, it is shown that a shrinkage estimator improves on the classical estimator under the loss function. Furthermore, from the extended Stein and Stein-Haff identities for our elliptically contoured distribution, the above result under normal errors is extended to the estimation problem under elliptical errors. We show that the shrinkage estimator obtained under normal models is better than the classical estimator under elliptical errors with the above loss function and hence we establish the robustness of the above shrinkage estimator.