亚慢性硝酸钇暴露对雌性大鼠学习记忆能力的影响

目的：观察稀土化合物硝酸钇[Y（NO₃）₃]亚慢性（90 d）暴露对大鼠学习记忆能力的影响，并探究其可能的机制，为全面评估稀土元素钇的健康风险提供科学依据。方法：选用刚离乳（PND21）SD雌性大鼠，根据质量随机分为4组，分别为对照组（ddH₂O），Y（NO₃）₃低剂量组[10 mg/（kg·d）]、中剂量组[40 mg/（kg·d）]和高剂量组[160 mg/（kg·d）]，每组15只。连续灌胃受试物90 d后进行旷场实验、高架十字迷宫实验、转棒实验、Morris水迷宫实验。水迷宫检测后，每组取5只雌鼠心脏原位灌注，进行脑组织病理学检查。每组剩余10只雌鼠摘取脑组织，紫外分光光度计检测雌鼠大脑皮质和海马中谷氨酸（Glu）的含量；Western blot检测海马组织中N-甲基-D-天冬氨酸（NMDA）受体蛋白表达情况。结果：与对照组相比，硝酸钇90 d暴露后，转棒实验中160 mg/（kg·d）剂量组大鼠在棒时间、在棒圈数、掉落速度明显升高（P<0.05）。在Morris水迷宫定位航向实验第4天时，40、160 mg/（kg·d）剂量组大鼠逃避潜伏期明显降低（P<0.05）；Morris水迷宫空间探索实验中，40 mg/（kg·d）剂量组大鼠穿越平台次数、目标象限游泳时间明显增加（P<0.05）；160 mg/（kg·d）剂量组穿越平台次数、进入目标象限次数、目标象限游泳时间明显增加（P<0.05）；160 mg/（kg·d）剂量组大鼠东北、东南、西南象限的逃避潜伏期明显低于西北象限的逃避潜伏期（P<0.05）。160 mg/（kg·d）剂量组大鼠海马中Glu含量和NMDA受体NR1含量均明显低于对照组（P<0.05）。40和160 mg/（kg·d）剂量组大鼠海马中NMDA受体NR2A含量明显低于对照组（P<0.05）。结论：硝酸钇亚慢性（90 d）暴露可以引起雌性大鼠空间学习记忆能力增强；硝酸钇可能通过降低海马组织神经元细胞外Glu含量，抑制NMDA受体激活，增强雌性大鼠的空间学习记忆能力。     

Hot Corrosion Behavior of Sputtered Nanocrystalline Coating with Yttrium Addition at 900 °C

The high temperature corrosion behavior of sputtered nanocrystalline K38 coating with and without yttrium addition under mixed molten salt film in air was investigated. Accelerated corrosion occurred on the coating without yttrium (Y) addition locally after 60 h exposure at 900°C, which resulted in negative weight gain in kinetics. A uniform and protective alumina scale formed on surface of the coating containing yttrium in comparison. Y enriched particle as corrosion product was observed on the top of alumina scale. The results indicated the beneficial influence of Y on the chemical stability of the protective scale in the presence of chloride. The mechanism was discussed.     

Structural Features of Y2O2SO4 via DFT Calculations of Electronic and Vibrational Properties

The traditional way for determination of molecular groups structure in crystals is the X-Ray diffraction analysis and it is based on an estimation of the interatomic distances. Here, we report the analysis of structural units in Y₂O₂SO₄ using density functional theory calculations of electronic properties, lattice dynamics and experimental vibrational spectroscopy. The Y₂O₂SO₄ powder was successfully synthesized by decomposition of Y₂(SO₄)₃ at high temperature. According to the electronic band structure calculations, yttrium oxysulfate is a dielectric material. The difference between the oxygen–sulfur and oxygen–yttrium bond nature in Y₂O₂OS₄ was shown based on partial density of states calculations. Vibrational modes of sulfur ions and [Y₂O₂²⁺] chains were obtained theoretically and corresponding spectral lines observed in experimental Infrared and Raman spectra.     

Substantial Improvement of High Temperature Strength of New-Generation Nano-Oxide-Strengthened Alloys by Addition of Metallic Yttrium

Oxide-dispersion-strengthened (ODS) Fe-Al-Y₂O₃-based alloys (denoted as FeAlOY) containing 5 vol. % of nano-oxides have a potential to become top oxidation and creep-resistant alloys for applications at temperatures of 1100–1300 °C. Oxide dispersoids cause nearly perfect strengthening of grains; thus, grain boundaries with limited cohesive strength become the weak link in FeAlOY in this temperature range. One of the possibilities for significantly improving the strength of FeAlOY is alloying with appropriate elements and increasing the cohesive strength of grain boundaries. Nearly 20 metallic elements have been tested with the aim to increase cohesive strength in the frame of preliminary tests. A positive influence is revealed for Al, Cr, and Y, whereby the influence of Y is enormous (addition of 1% of metallic Y increases strength by a factor of 2), as it is presented in this paper.     

Dislocation of polyfocal full-optics accommodative intraocular lens after neodymium-doped yttrium aluminum garnet capsulotomy in vitrectomized eye

We report a case of dislocation of WIOL-CF^® polyfocal full-optics intraocular lens (IOL) after neodymium-doped yttrium aluminum garnet (Nd: YAG) laser capsulotomy in the vitrectomized eye. At 22 months before the dislocation of the IOL, a 55-year-old male patient underwent phacoemulsification with WIOL-CF^® IOL implantation in a local clinic and 10 months after the cataract surgery the patient underwent pars plana vitrectomy, endolaser photocoagulation and 14% C₃F₈ gas tamponade for the treatment of rhegmatogenous retinal detachment. At 9 months after the vitrectomy, the patient visited our clinic for a sudden decrease of vision after Nd: YAG capsulotomy in the local clinic. On fundus examination, the dislocated IOL was identified and the Nd: YAG capsulotomy site and the larger break, which is suspected to have been a route of the dislocation were observed in the posterior capsule.     

钇稀土粉尘的生物学作用及其车间卫生标准的研究

本文从钇稀土生产矿的劳动卫生、职业流行病学调查及动物体内、外实验研究了钇稀土粉尘的生物学作用,并对钇稀土生产车间空气粉尘卫生标准进行探讨。作业场所粉尘浓度在1.3—25.9mg/m~3,25名接尘工人中X线O~+检出率为16%,平均接尘工龄为8.8年。接尘组工人的肺功能及化验检查某些指标改变较对照组有显著差异,经动物体内外实验研究,钇组稀土粉尘显示的致肺纤维化作用和细胞毒性大于铈组粉尘但显著低于石英粉尘,根据本研究结果提出了生产车间钇组稀土粉尘卫生标准为3mg/m~3的建议值。     

Imaging characteristics following 90yttrium microsphere treatment for unresectable liver cancer

Selective internal radiation therapy (SIRT) with (90)yttrium microspheres - also known as radioembolisation - is a relatively new interventional radiology technique offering symptomatic and survival advantages for patients with unresectable liver cancer. However, in delivering both beta-particle brachytherapy and embolisation of tumour vasculature, SIRT produces biological sequelae and imaging characteristics distinct from other treatment modalities. Current CT interpretation criteria consistently under-report pathological responses to radioembolisation, diminishing both the prognosis and subsequent treatment choices for responding patients. However, newer criteria incorporating both tumour dimensions and enhancement characteristics improve the correlation with histopathology and provide substantially earlier confirmation of response. CT following radioembolisation may also identify parenchymal features that are often benign but may be mistaken for tumour progression. This review outlines imaging criteria specific to SIRT, including assessment of tumour response and interpretation of both lesion and parenchymal characteristics. The adjunctive role of additional modalities such as positron emission tomography is also addressed.