ADDITIVE OPERATORS PRESERVING RANK-ADDITIVITY ON SYMMETRY MATRIX SPACES

Tang, Xiao-Min,Cao, Chong-Guang 한국전산응용수학회 2004 Journal of applied mathematics & informatics Vol.14 No.1

We characterize the additive operators preserving rank-additivity on symmetry matrix spaces. Let $S_{n}(F)$ be the space of all $n\;\times\;n$ symmetry matrices over a field F with 2, $3\;\in\;F^{*}$, then T is an additive injective operator preserving rank-additivity on $S_{n}(F)$ if and only if there exists an invertible matrix $U\;\in\;M_n(F)$ and an injective field homomorphism $\phi$ of F to itself such that $T(X)\;=\;cUX{\phi}U^{T},\;\forallX\;=\;(x_{ij)\;\in\;S_n(F)$ where $c\;\in;F^{*},\;X^{\phi}\;=\;(\phi(x_{ij}))$. As applications, we determine the additive operators preserving minus-order on $S_{n}(F)$ over the field F.

Grain Boundary-Mediated Reduction of Radiation Defects in Different W-Based Alloys

Xiao‑Tong Li,Xiao‑Zhi Tang,Ya‑Fang Guo 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.9

Grain boundaries (GBs) are believed as potent defect sinks that contribute to the radiation damage reduction of materials. The defect-GB interaction has been extensively studied in pure metals, but only a few works shed light on the influence ofmaterial component such as alloying elements. In this study, the GB-mediated reduction of radiation defects in four W-basedalloys (W–Re, W–Ta, W–Mo and W–V) is systematically investigated by atomistic simulations. Quantitative results showthat the defect reduction in W-based alloys is significantly decreased comparing with elementary W. The principal reasonfor this decrease is the presence of various micro configurations where the solute-defect binding interactions are strong. Solutes with high local stress for each atom have a positive effect on the absorption of interstitials by GB. The ability ofGB to absorb interstitials is enhanced with the increasing temperature, and also the accumulation of vacancies is increasedwhen the temperature is as high as 1200 K. The findings in this work provide useful information on the design of radiationtolerance materials.

Monosaccharide as a Central Scaffold Toward the Construction of Salicylate-Based Bidentate PTP1B Inhibitors via Click Chemistry

Tang, Yan-Hui,Hu, Min,He, Xiao-Peng,Fahnbulleh, Sando,Li, Cui,Gao, Li-Xin,Sheng, Li,Tang, Yun,Li, Jia,Chen, Guo-Rong Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.3

The discovery of carbohydrate-based bioactive compounds has recently received considerable interest in the drug development. This paper stresses on the application of 1-methoxy-O-glucoside as the central scaffold, whereas salicylic pharmacophores were introduced with diverse spatial orientations probing into the structural preference of an enzymatic target, i.e. protein tyrosine phosphatase 1B (PTP1B). By employing regioselective protection and deprotection strategy, 2,6-, 3,4-, 4,6- and 2,3-di-O-propynyl 1-methoxy-O-glucosides were previously synthesized and then coupled with azido salicylate via click chemistry in forming the desired bidentate salicylic glucosides with high yields. The inhibitory assay of the obtained triazolyl derivatives leads to the identification of the 2,3-disubstituted salicylic 1-methoxy-O-glucoside as the structurally privileged PTP1B inhibitor among this bidentate compound series with micromole-ranged $IC_{50}$ value and reasonable selectivity over other homologous PTPs tested. In addition, docking simulation was conducted to propose a plausible binding mode of this authorized inhibitor with PTP1B. This research might furnish new insight toward the construction of structurally different bioactive compounds based on the monosaccharide scaffold.

Additive operators preserving rank-additivity on symmetry matrix spaces

Xiao-Min Tang,Chong-Guang Cao 한국전산응용수학회 2004 Journal of applied mathematics & informatics Vol.14 No.-

We characterize the additive operators preserving rank-additivity on symmetry matrix spaces. Let Sn(F) be the space of all n × n symmetry matrices over a field F with 2, 3 2 F, then T is an additive injective operator preserving rank-additivity on Sn(F) if and only if there exists an invertible matrix U 2 Mn(F) and an injective field homomorphism of F to itself such that T(X) = cUXUT , 8X = (xij ) 2 Sn(F) where c 2 F,X = ((xij )). As applications, we determine the additive operators preserving minus-order on Sn(F) over the field F.

Synthesis of (Imido)vanadium(V) Complexes Containing 8-(2,6-Dimethylanilide)-5,6,7-trihydroquinoline Ligands: Highly Active Catalyst Precursors for Ethylene Dimerization

Tang, Xiao-Yan,Igarashi, Atsushi,Sun, Wen-Hua,Inagaki, Akiko,Liu, Jingyu,Zhang, Wenjuan,Li, Yue-Sheng,Nomura, Kotohiro American Chemical Society 2014 Organometallics Vol.33 No.4

<P>A series of (imido)vanadium(V) dichloride complexes containing 8-(2,6-dimethylanilide)-5,6,7-trihydroquinoline ligands of the type V(NR)Cl<SUB>2</SUB>[8-(2,6-Me<SUB>2</SUB>C<SUB>6</SUB>H<SUB>3</SUB>)N(C<SUB>9</SUB>H<SUB>10</SUB>N)] (R = Ad (<B>3</B>), 2-MeC<SUB>6</SUB>H<SUB>4</SUB> (<B>4</B>), 2,6-Me<SUB>2</SUB>C<SUB>6</SUB>H<SUB>3</SUB> (Ar, <B>5</B>)) have been prepared and identified, and their structures have been determined by X-ray crystallographic analysis. The ethylene dimerization catalyst generated from complex <B>3</B> upon treatment with an excess amount of MAO exhibited remarkable catalytic activities (e.g. TOF = 9600000 h<SUP>–1</SUP> (2670 s<SUP>–1</SUP>), Al/V = 4000 (molar ratio)), affording 1-butene as the major product (95.0–99.4%). The activities of <B>3</B> and <B>4</B> were higher than those exhibited by the corresponding 2-(anilide)methylpyridine analogues; <B>3</B> showed higher 1-butene selectivity than the others and the activity did not decrease remarkably at 50 °C. Complex <B>5</B> afforded a mixture of polymer and oligomers with low activities, suggesting that a fine tuning of both the imido and the anionic donor ligands plays an essential role in this catalysis.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/orgnd7/2014/orgnd7.2014.33.issue-4/om401119y/production/images/medium/om-2013-01119y_0004.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/om401119y'>ACS Electronic Supporting Info</A></P>

Prognosis of Eight Chinese Cases of Primary Vaginal Yolk Sac Tumor with a Review of the Literature

Tang, Qiong-Lan,Jiang, Xue-Feng,Yuan, Xiao-Ping,Liu, Yong,Zhang, Lin,Tang, Xiao-Feng,Zhou, Jia-Jia,Li, Hai-Gang,Fang, Jian-Pei,Xue, Lin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

Background: Primary vaginal yolk sac tumor is a rare malignancy in the pediatric population, and a diagnostic challenge and appropriate initial treatment remains unsolved. The aim of this study was to investigate the clinicopathologic features, treatment and prognosis of this tumor. Materials and Methods: Eight cases of primary vaginal yolk sac tumor were reported with a literature review. Results: There were 4 pure yolk sac tumor cases and four mixed germ cell tumors containing yolk sac tumor element, including two cases with embryonal carcinoma and two cases with embryonal carcinoma and dysgerminoma. Partial vaginectomy was performed in four cases and all patients received chemotherapy. 85 cases in literatures were reviewed and 9 cases were misdiagnosed. Follow-up data was available in 77 cases and 5-year overall survival rate was 87.6%. 5-year survival rate of biopsy with chemotherapy, conservative surgery with chemotherapy and radical surgery with chemotherapy was 91.1%, 100% and 28.6%, respectively (p<0.001). Compared to cases without relapse or metastasis after initial treatment, patients with relapse or metastasis had a shorter overall survival (35.6% vs 96.6%, p<0.001). Conclusions: Mixed germ cell tumor containing yolk sac tumor element was not uncommon and partial vaginectomy may be a good choice for primary vaginal mixed yolk sac tumor type to eradicate local tumor cells and provide complete information for pathological diagnosis and postoperative adjuvant therapy.

Effects of Ubiquitin-conjugating Enzyme 2C on Invasion, Proliferation and Cell Cycling of Lung Cancer Cells

Tang, Xiao-Kui,Wang, Ke-Jian,Tang, Yu-Kui,Chen, Li Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.7

The aims of this study were to investigate the influence of ubiquitin- conjugating enzyme E2C (UBE2C) on biological behavior of lung cancer cells. Using MTT, flow cytometry and invasion assays, we detected UBE2C expression and evaluated its biological properties in these cells, including effects on proliferation, the cell cycle profile and invasive capability. Compared with control cells, the UBE2C transfected cells demonstrated increased cellular proliferation (p<0.05). UBE2C transfected cells also had a lower percentage in G1 phase and a higher percentage in S phase (p<0.05). Importantly, the UBE2C transfected cells had a notable enhancement of cell numbers penetrating the basement membrane compared with the control group (p<0.05). Ectopic up-regulation UBE2C promoted the growth of lung cancer cells in vivo. Furthermore, we found UBE2C increased the expression of cyclin D1 and MMP-2. These results show UBE2C may represent a potential therapeutic target for lung cancer.

LINEAR MAPS PRESERVING PAIRS OF HERMITIAN MATRICES ON WHICH THE RANK IS ADDITIVE AND APPLICATIONS

TANG, XIAO-MIN,CAO, CHONG-GUANG 한국전산응용수학회 2005 Journal of applied mathematics & informatics Vol.19 No.1

Denote the set of n ${\times}$ n complex Hermitian matrices by Hn. A pair of n ${\times}$ n Hermitian matrices (A, B) is said to be rank-additive if rank (A+B) = rank A+rank B. We characterize the linear maps from Hn into itself that preserve the set of rank-additive pairs. As applications, the linear preservers of adjoint matrix on Hn and the Jordan homomorphisms of Hn are also given. The analogous problems on the skew Hermitian matrix space are considered.

Patterns of Lymph Node Recurrence after Radical Surgery Impacting on Survival of Patients with pT1-3N0M0 Thoracic Esophageal Squamous Cell Carcinoma

Xiao-li Chen,,Tian-wu Chen,Zhi-jia Fang,Xiao-ming Zhang,Zhen-lin Li,Hang Li,Hong-jie Tang,Li Zhou,Dan Wang,Zishu Zhang 대한의학회 2014 Journal of Korean medical science Vol.29 No.2

The aim of this study was to investigate how patterns of lymph nodes recurrence after radical surgery impact on survival of patients with pT1-3N0M0 thoracic esophageal squamous cell carcinoma. One hundred eighty consecutive patients with thoracic esophageal squamous cell carcinoma underwent radical surgery, and the tumors were staged as pT1-3N0M0 by postoperative pathology. Lymph nodes recurrence was detected with computed tomography 3-120 months after the treatment. The patterns of lymph nodes recurrence including stations, fields and locations of recurrent lymph nodes, and impacts on patterns of survival were statistically analyzed. There was a decreasing trend of overall survival with increasing stations or fields of postoperative lymph nodes involved (all P<0.05). Univariate analysis showed that stations or fields of lymph nodes recurrence, and abdominal or cervical lymph nodes involved were prognostic factors for survival(all P<0.05). Cox analyses revealed that the field was an independent factor (P<0.05, odds ratio=2.73). Lymph nodes involved occurred predominantly in cervix and upper mediastinum (P<0.05). In conclusion, patterns of lymph node recurrence especially the fields of lymph nodes involved are significant prognostic factors for survival of patients with pT1-3N0M0 thoracic esophageal squamous cell carcinoma.

IRS-2 Partially Compensates for the Insulin Signal Defects in IRS-1^-/- Mice Mediated by miR-33

Tang, Chen-Yi,Man, Xiao-Fei,Guo, Yue,Tang, Hao-Neng,Tang, Jun,Zhou, Ci-La,Tan, Shu-Wen,Wang, Min,Zhou, Hou-De Korean Society for Molecular and Cellular Biology 2017 Molecules and cells Vol.40 No.2

Insulin signaling is coordinated by insulin receptor substrates (IRSs). Many insulin responses, especially for blood glucose metabolism, are mediated primarily through Irs-1 and Irs-2. Irs-1 knockout mice show growth retardation and insulin signaling defects, which can be compensated by other IRSs in vivo; however, the underlying mechanism is not clear. Here, we presented an Irs-1 truncated mutated mouse ($Irs-1^{-/-}$) with growth retardation and subcutaneous adipocyte atrophy. $Irs-1^{-/-}$ mice exhibited mild insulin resistance, as demonstrated by the insulin tolerance test. Phosphatidylinositol 3-kinase (PI3K) activity and phosphorylated Protein Kinase B (PKB/AKT) expression were elevated in liver, skeletal muscle, and subcutaneous adipocytes in Irs-1 deficiency. In addition, the expression of IRS-2 and its phosphorylated version were clearly elevated in liver and skeletal muscle. With miRNA microarray analysis, we found miR-33 was down-regulated in bone marrow stromal cells (BMSCs) of $Irs-1^{-/-}$ mice, while its target gene Irs-2 was up-regulated in vitro studies. In addition, miR-33 was down-regulated in the presence of Irs-1 and which was up-regulated in fasting status. What's more, miR-33 restored its expression in re-feeding status. Meanwhile, miR-33 levels decreased and Irs-2 levels increased in liver, skeletal muscle, and subcutaneous adipocytes of $Irs-1^{-/-}$ mice. In primary cultured liver cells transfected with an miR-33 inhibitor, the expression of IRS-2, PI3K, and phosphorylated-AKT (p-AKT) increased while the opposite results were observed in the presence of an miR-33 mimic. Therefore, decreased miR-33 levels can up-regulate IRS-2 expression, which appears to compensate for the defects of the insulin signaling pathway in Irs-1 deficient mice.