Photoreduction of Copper Ions Using Silica–Surfactant Hybrid and Titanium (IV) Oxide under Sulfuric Acid Conditions

Photoreduction of Cu²⁺ ions to Cu metal by titanium(IV) oxide (TiO₂) was conducted in the presence of a silica–surfactant hybrid under sulfuric acid conditions. After irradiation, a dark-red color, reflections due to Cu metal in the X-ray diffraction pattern, and peaks due to Cu 2p_1/2 and 2p_3/2 in the X-ray photoelectron spectrum indicated the precipitation of Cu metal in the product. In addition, an increase in the Brunauer–Emmett–Teller specific surface area from 36 and 45 m²/g for the silica–surfactant and TiO₂, respectively, to 591 m²/g for the product, and a decrease in the intensity of the C-H stretching band in the Fourier–transform infra-red spectra implied the removal of surfactant during the reaction. These characteristics were never observed when TiO₂ was used solely. Therefore, this study indicated that the photoreduction of Cu²⁺ ions to Cu metal by TiO₂ was facilitated under the sulfuric acid medium, where the surfactants extracted from silica–surfactant hybrids by protons in the acidic condition were successfully photo-oxidized by TiO₂. Thus, this study presents a new application of the conversion of a silica–surfactant hybrid into mesoporous silicas.     

重离子治疗恶性肿瘤对机体免疫功能的影响

目的 通过检测患者免疫球蛋白、T细胞亚群及NK细胞的变化.探讨重离子放射治疗恶性肿瘤是否对机体免疫功能产生影响.方法 将26例经病理学证实的恶性肿瘤患者采用重离子束局部外照射,在治疗前后分别取患者外周血,采用化学发光法,用全自动生化分析仪测定血清IgG、IgA、IgM的量,用流式细胞仪检测放疗前后T细胞亚群及NK细胞比例.结果 NK细胞、CD4^＋ T细胞、CD8^＋T细胞及CD4^＋ T/CD8^＋T在治疗前后无明显变化,免疫球蛋白IgG、IgA、IgM在治疗前后无明显变化.结论 重离子治疗对免疫功能无明显影响.     

离子法测定中蒙药材苦杏仁中六种阴离子的含量

目的: 建立一种同时测定中蒙药苦杏仁药材中F^－、Cl^－、Br^－、NO^－₃ 、SO2^－₄ 、PO^3－₄ 阴离子的含量测定方
法。方法:采用离子色谱法、阴离子色谱柱、氢氧化钠梯度淋洗、电导检测苦杏仁6 种无机阴离子。结果: F^－、
Cl^－、Br^－、NO^－₃ 、SO₂^－4 、PO^3－₄ 的加样回收率介于97%～ 102%,苦杏仁中F－、Cl－、Br－、NO－3 、SO2－4 、PO3－
4 重复性良好,含量分别为0．057%0．084%,0．063%,0．070%,0．30%,0．12%。结论: 离子色谱法可以同时检测苦杏仁中6 种阴离
子,灵敏度高,结果准确可行,为苦杏仁的质量控制提供了一种简便快速的方法．     

MPP+对体外培养的中脑多巴胺能神经元活性的影响

目的　探讨 1 甲基 4 苯基吡啶 (MPP+ )对体外培养的中脑多巴胺能神经元的影响。方法　将不同浓度的MPP+ 加入体外培养的中脑多巴胺能神经元培养液中 ,分别测定 [3H]多巴胺和 [3H]胆碱摄取能力及细胞内的多巴胺含量 ,并进行酪氨酸羟化酶(TH)免疫细胞化学染色。结果　MPP+ 对体外培养的中脑多巴胺能神经元的 [3H]多巴胺摄取力有明显的抑制作用 (P <0 0 5 ) ;但对[3H]胆碱摄取力无抑制作用 (P >0 0 5 ) ;这种抑制作用在未抑制胶质细胞组明显强于抑制胶质细胞组 (P <0 0 5 ) ;加用MPP+ 后中脑多巴胺能神经元细胞内的多巴胺含量明显减少 (P <0 0 5 ) ,TH阳性细胞明显减少 (P <0 0 5 )。结论　MPP+ 对体外培养的中脑多巴胺能神经元活性有明显的抑制作用     

Theoretical ionization and capture cross sections for DNA nucleobases impacted by light ions

Abstract

Purpose: Although DNA lesions are considered of prime importance for describing the post-irradiation cellular survival, they still remain rarely studied on both experimental and theoretical sides. Under these conditions, we here propose different theoretical models for predicting the single ionization and single capture total cross sections for DNA bases impacted by protons.

Material and methods: Three theoretical approaches are developed: a first classical one based on a classical trajectory Monte Carlo (CTMC) model and two quantum mechanical ones, namely, a Coulomb Born (CB1) and a continuum-distorted wave eikonal-initial-state (CDW-EIS) model.

Results: Ionization and capture processes induced by protons on DNA bases (adenine, cytosine, thymine and guanine) are here studied in terms of total cross sections.

Conclusions: A very good agreement is obtained between the different models at high enough impact velocities but discrepancies are observed between them at low impact energies (E_i ≤ 100 keV). Furthermore, it is shown that the theoretical cross sections underestimate the rare existing experimental data in particular for adenine and thymine whereas a reasonable agreement is found for cytosine.     

单细胞电泳观察重离子辐照人肝癌细胞所致DNA损伤

目的 研究重离子对肿瘤细胞DNA的损伤程度，为重离子治癌的临床应用积累必要的基础数据。方法 用80MeV／u氖离子射线诱发SMMC-7721细胞DNA辐射损伤，利用单细胞凝胶电泳(single cell gelelectrophoresis，SCGE)实验方法处理细胞，并对结果进行统计分析。结果 氖离子辐照以剂量依赖的方式引起SMMC-7721细胞DNA迁移长度的增加，且拖尾长度与剂量呈线性正相关；同时，拖尾的细胞数(即损伤的细胞数)在剂量大于2Gy时100％细胞损伤。结论 重离子射线对DNA有强致损效应。     

Comparative study of dose distribution between carbon ion radiotherapy and photon radiotherapy for head and neck tumor

PURPOSE: A comparative treatment planning study has been performed between carbon ion radiotherapy (CIRT) and photon radiotherapy [three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT)] to assess the potential improvements and limitations that could result for locally advanced, nonresectable head and neck tumors. MATERIALS AND METHODS: Seven patients, originally treated with CIRT, were randomly selected for the comparative study. The evaluations analyzed using dose-volume histogram parameters, conformity index, inhomogeneity coefficient, and dose to the organs at risk (OARs). RESULTS: The mean conformity index was 1.46, 1.43, and 1.22 for 3D-CRT, IMRT, and CIRT, respectively. The mean inhomogeneity coefficient was 0.05, 0.07, and 0.02 for 3D-CRT, IMRT, and CIRT respectively. Photon plans resulted in greater volumes of normal tissues at 10% to 95% isodose levels compared with the corresponding carbon ion plans where the volumes increased by a factor of 1.2 to 2.7 for 3D-CRT and 1.2 to 2.0 for IMRT. CONCLUSION: CIRT has the potential to improve the target dose conformity, inhomogeneity coefficient, and OAR sparing when compared with 3D-CRT and IMRT. Compared with 3D-CRT, normal tissue exposure was reduced mainly in the mid-to low-isodose levels using IMRT. Additional improvement was obtained using CIRT.     

低分子量有机酸含量测定方法探讨

目的: 用色谱法构建一种简洁、快速、准确度高的检测低分子量有机酸的方法。方法: 气相色谱法和
离子色谱法同时测定甲酸、乙酸、丙酸、丁酸和乳酸。结果: 由于甲酸和乳酸的沸点问题,用气相色谱法不能同时
测定,而离子色谱法前处理简单,操作方便,可以同时测定。结论: 离子色谱法是同时测定低分子量有机酸含量
的有效方法。     

野生型PTEN 过表达对体外活化肝星状细胞内钙离子浓度的影响

目的 探讨野生型第10 号染色体缺失的磷酸酶张力蛋白同源物基因（PTEN）过表达对体外活化肝星状细胞（HSC）内钙离子浓度的影响。方法 体外培养活化大鼠肝星状细胞系（HSC-T6）,利用腺病毒载体,将野生型PTEN 基因转染活化HSC ;Western blot 及实时荧光定量聚合酶链反应（qrt-PCR）检测HSC 的PTEN 蛋白及mRNA 表达;采用钙离子荧光探针Rhod-2/AM,于激光扫描共聚焦显微镜下检测HSC 内钙离子浓度变化。实验分组：① Control 组：腺病毒转染时以DMEM 代替病毒液;② Ad-GFP 组：转染表达绿色荧光蛋白（GFP）的对照空病毒Ad-GFP ;③ Ad-PTEN 组：转染携带野生型PTEN 基因并表达GFP 的重组腺病毒Ad-PTEN。结果 野生型PTEN 在活化大鼠HSC 大量表达,3 组HSC 内钙离子浓度比较,差异有统计学意义（P <0.05）,Ad-PTEN 组HSC 内钙离子浓度（251.60±90.88）低于Control 组（1 953.95±132.99）及Ad-GFP 组（1 937.57±115.17）,而Control 组与Ad-GFP 组之间HSC 内钙离子浓度比较,差异无统计学意义（P >0.05）。结论 野生型PTEN 过表达可降低体外活化大鼠HSC 内钙离子浓度。