多孔胃管洗胃的数学方程

提出了多孔胃管洗胃的方程及其拟合方程.把多孔胃管的终端划分为连续的含孔微元,用离散分析研究了各微元流体在洗胃冲吸中的方程,从模拟洗胃实验得出各孔流速的约束条件,为胃管的工程估算与合理开孔提供数学依据.     

超声双重造影及MRI对胃癌诊断及术前T分期的对比研究

选取2017年8月~2019年2月我院收治的胃癌患者130例作为研究对象,依据患者病理诊断结果作为金标准,分析磁共振成像(magnetic resonance imaging,MRI)与超声双重造影对胃癌的诊断价值及术前T分期的价值。结果显示,超声双重造影共检出120例胃癌患者,出现10例漏诊,MRI共检出109例胃癌患者,出现21例漏诊。金标准共检出52例T1期、32例T2期、26例T3期、20例T4期患者,超声双重造影诊断出T1期48例,符合率92.31%;T2期30例,符合率93.75%;T3期24例,符合率92.31%;T4期18例,符合率90.00%,进一步分析显示,超声双重造影对不同胃癌T分期的诊断价值均高于MRI。因此,超声双重造影对胃癌的诊断价值及对术前T分期诊断价值均高于MRI。     

Total Synthesis of Mycolactones A and B

First and second generation total syntheses of mycolactones A and B are reported. The first generation total synthesis unambiguously confirmed our earlier assignment of the relative and absolute stereochemistry of mycolactones A and B. Knowledge of the chemical properties of the mycolactones accumulated through the first generation total synthesis allowed us to implement several major improvements to the original synthesis, including: (1) optimizing the choice of protecting groups, (2) eliminating the unnecessary adjustment of protecting groups, and (3) improving the overall stereoselectivity and synthetic efficiency. The second generation total synthesis consists of 21 longest linear steps, with 6.3% overall yield.     

Separation and identification of steroidal compounds with cytotoxic activity against human gastric cancer cell lines <Emphasis Type="Italic">in vitro</Emphasis> from the rhizomes of <Emphasis Type="Italic">Paris polyphylla</Emphasis> var. <Emphasis Type="Italic">chinensis</Emphasis>

A novel steroidal saponin, along with 12 known steroidal compounds, was isolated from the rhizomes of Paris polyphylla var. chinensis. Spectral data, including two-dimensional NMR, showed that the structure of the novel saponin was 3β,21-dihydroxypregnane-5-en-20S-(22,16)-lactone-1-O-α-L-rhamnopyranosyl(1→2)-[β-D-xylopyranosyl(1→3)]-β-D-glucopyranoside. The isolated steroidal compounds were evaluated for their cytotoxic activity on human gastric cancer cell line HepG₂, SGC7901, BxPC3. Diosgenin-3-O-α-L-rhamnopyranosyl(1→2)[α-L-rabinofuranosyl(1→4)]-β-D-glucopyranoside exhibited the most potent cytotoxic activity among the isolated steroids. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 556–560, November–December, 2007.     

Copper nanoparticles supported on polyethylene glycol-modified magnetic Fe3O4 nanoparticles: Its anti-human gastric cancer investigation

In that work, we have described the synthesis of novel Cu NPs decorated polyethylene glycol (PEG₂₀₀₀) coated magnetic nanoparticles (Fe₃O₄/PEG2000/Cu NPs) in an eco-friendly pathway applying Green Tea extract as reducing/stabilizing agent. The morphological and physicochemical features of the prepared nanocomposite were determined using several advanced techniques like ICP-OES, FE-SEM, EDX, atomic mapping, TEM, VSM, and XRD studies. In the antioxidant test, the IC50 of Fe₃O₄/PEG₂₀₀₀/Cu nanocomposite and BHT against DPPH free radicals were 198 and 85 µg/mL, respectively. In the cellular and molecular part of the recent study, the treated cells with Fe₃O₄/PEG₂₀₀₀/Cu nanocomposite were assessed by MTT assay for 48 h about the cytotoxicity and anti-human gastric cancer properties on normal (HUVEC) and gastric cancer cell lines i.e. NCI-N87 and MKN45. The IC50 of Fe₃O₄/PEG₂₀₀₀/Cu nanocomposite were 316 and 131 µg/mL against NCI-N87 and MKN45 cell lines, respectively. The viability of malignant gastric cell line reduced dose-dependently in the presence of Fe₃O₄/PEG₂₀₀₀/Cu nanocomposite. It seems that the anti-human gastric cancer effect of recent nanoparticles is due to their antioxidant effects.     

Synthesis of Cytotoxic Iron-Containing Macrocycles Through Unexpected C(sp2)−C(sp2) Bonds Formation

In previous reports, it has been demonstrated that cyclometalated iron(II/III) complexes can be prepared by reacting iron(0) precursors and mercurated or brominated derivatives. However, in this report, the reaction between [Fe₃(CO)₁₂] and mercurated 6-phenyl-2,2′-bipyridine or brominated 2,6-diphenyl-pyridine pincer derivatives led to compounds in which C(sp²)−C(sp²) bonds have been formed between two ligands. A 16-electron iron(II) complex ( 1Cl ) bearing a tetradentate ligand originating from the dimerization of 6-phenyl-2,2′-bipyridine was isolated, while a protonated 14-membered macrocycle with [FeBr₄]⁻ as counterion ( 2 ) was obtained from 2,6-diphenyl-pyridine. Studies by X-ray diffraction crystallography, NMR, UV-vis and cyclic voltammetry confirmed the structures. Additionally, the cytotoxicity of the new compounds toward gastric cancer cell lines was evaluated, and it was established that the presence of the iron(II) center was crucial for an elevated activity.     

膜结合型TNF－α基因对人胃癌细胞生长的影响

探讨突变的膜结合型ＴＮＦ－α基因对人胃癌细胞生长的影响,方法：用突变的膜结合型ＴＮＦ－α基因作为目的基因,以逆转录病毒为载体将目的基因导入人胃癌细胞ＭＧＣ８０３,经Ｇ４１８筛选得到抗性克隆ＭＧＣ＾Ｔ８０３,结果：Ｓｏｕｔｈｅｒｎ杂交证实目的基因已整合在ＭＧＣ＾Ｔ８０３细胞中,用ＥＬＩＳＡ方法检测ＭＧＣ＾Ｔ８０３细胞表面ＴＮＦ－α表达量明显增高,ＭＧＣ＾Ｔ８０３细胞形态,体外增殖能力无显著改变,裸鼠     

纳米TiO2对胃癌细胞的光催化氧化杀伤效应

纳米TiO2对胃癌细胞的光催化氧化杀伤效应;胃癌细胞(BGC-823);抗癌剂     

Targeting Cytotoxin-Associated Antigen A,a Virulent Factor of Helicobacter pylori-Associated Gastric Cancer: Structure-Based In Silico Screening of Natural Compounds

Gastric cancer is the fifth most frequent cancer and the third major cause of mortality worldwide. Helicobacter pylori, a bacterial infection linked with GC, injects the cytotoxin-associated antigen A (CagA; an oncoprotein) into host cells. When the phosphorylated CagA protein enters the cell, it attaches to other cellular components, interfering with normal cellular signaling pathways. CagA plays an important role in the progression of GC by interacting with phosphatidylserine of the host cell membrane. Therefore, disrupting the CagA–phosphatidylserine connection using small molecules appears to be a promising therapeutic approach. In this report, we screened the natural compounds from ZINC database against the CagA protein using the bioinformatics tools. Hits were initially chosen based on their physicochemical, absorption, distribution, metabolism, excretion, and toxicity (ADMET) characteristics, as well as other drug-like characteristics. To locate safe and effective hits, the PAINS filter, binding affinities estimation, and interaction analysis were used. Three compounds with high binding affinity and specificity for the CagA binding pocket were discovered. The final hits, ZINC153731, ZINC69482055, and ZINC164387, were found to bind strongly with CagA protein, with binding energies of −11.53, −10.67, and −9.21 kcal/mol, respectively, which were higher than that of the control compound (−7.25 kcal/mol). Further, based on binding affinity and interaction pattern, two leads (ZINC153731, ZINC69482055) were chosen for molecular dynamics (MD) simulation analysis. MD results showed that they displayed stability in their vicinity at 100 ns. This study suggested that these compounds could be used as possible inhibitors of CagA protein in the fight against GC. However, additional benchwork tests are required to validate them as CagA protein inhibitors.