Acute Promyelocytic Leukemia in Children: A Model of Precision Medicine and Chemotherapy-Free Therapy

Acute promyelocytic leukemia (APL) represents a paradigm of precision medicine. Indeed, in the last decades, the introduction of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) completely revolutionized the therapeutic approach to this previously highly fatal disorder. This entirely chemotherapy-free treatment, which provided excellent survival rates, has been initially validated in adults and, recently, translated in the pediatric setting. This review summarizes currently available data on the use of ATRA and ATO combination in pediatric APL, providing a particular focus on peculiar issues and challenges, such as the occurrence of pseudotumor cerebri and death during induction (early death), as well as the advantage offered by the ATO/ATRA combination in sparing long-term sequelae.     

Engineering 2D Arsenic-Phosphorus Theranostic Nanosheets

As an anticancer drugs, arsenic trioxide (ATO) has been certified to efficiently treat refractory acute promyelocytic leukemia (APL). Unfortunately it suffers from limited therapeutic potency for solid tumors due to its in vivo restricted administration dose and rapid renal clearance. Herein, distinct 2D arsenic-phosphorus (AsP) nanosheets are engineered by adopting an alloy strategy followed by exfoliation, which can confine toxic arsenic into AsP crystals, thus significantly improving the biosafety and biocompatibility of arsenic-based chemotherapeutic drugs. Of particular note, the high light absorption and strong photothermal-conversion efficiency (37.6%) in the second near infrared biowindow (NIR-II) of AsP nanosheets not only endow them with desirable contrast-enhanced photoacoustic imaging properties, but also achieve efficient local tumor hyperthermia, which further synergistically triggers the in-situ transformation from low toxic/nontoxic AsP crystals into highly toxic arsenic species, exerting a strong arsenic-mediated antineoplastic effect. Both in vitro and in vivo data verify the synergy between photonic therapy in NIR-II and enhanced chemotherapy as enabled by AsP nanosheets, paving the way for efficient nanomedicine-enabled arsenic-based chemotherapeutic tumor treatment.     

有色冶炼二次含砷物料碱法脱砷工艺现状

分析了典型二次含砷物料化学成分特点,概括了当前有色冶炼工业中产生的二次含砷物料碱法脱砷工艺及原理,主要包括湿法脱砷工艺和火法—湿法联合脱砷工艺。其中,碱法脱砷工艺常用NaOH单碱浸出、NaOH-Na_2S混合碱浸出和NaOH+Na_2S混合碱两段浸出三种体系,并采用双氧水、加压、曝气、微波、球磨等氧化手段强化砷的浸出;火法—湿法联合脱砷工艺主要有低温碱性熔炼—水浸、焙烧预氧化—碱性浸出以及低温碱性焙烧—热水浸出工艺,低温碱性焙烧—热水浸出工艺选择性脱砷效果好,物料普适性广。最后,结合现有研究指出了碱法脱砷工艺存在的问题及二次含砷物料无害化、资源化研究方向。     

湿法磷酸净化脱砷的研究现状

随着食品、医药及电子行业的不断发展，磷酸及磷酸盐的市场需求量不断增大，并且对磷酸的品质要求也越来越高，尤其是对湿法磷酸中砷杂质的要求，湿法磷酸中砷的含量将直接影响其在磷精细化工领域的应用，因此湿法磷酸中砷的高效、安全去除是亟待解决的一大难题。本文主要对湿法净化磷酸脱砷技术的研究情况进行综述，比较了几种湿法净化磷酸脱砷工艺的优缺点，介绍了较常见的化学沉淀法、结晶法，以及新兴的电沉积法、垂直区域熔融法和微反应器脱砷工艺的应用前景，并指出这些新兴的脱砷工艺将成为今后湿法磷酸的净化脱砷的发展方向，如能解决将这些脱砷工艺在实际中的问题，将会对磷酸工业的发展提供一个更有力的支持。     

有色金属工业含砷污染物处理研究进展

综述了有色金属工业砷污染物的来源及其无害化处理的方法,分析了包封固砷(水泥固化和玻璃固化)和矿物固砷(钙盐、铝盐、镁盐、硫化沉淀法)的优缺点和局限性,重点对将砷以臭葱石形式进行安全处理的合成方法和浸出稳定性的研究现状进行阐述。分析表明,晶态臭葱石合成是将砷以臭葱石形式进行安全处置的基础,稳定性是关键,进一步降低溶液过饱和度以实现大尺寸、高稳定性臭葱石的合成是发展方向。     

Genetic Carriers and Genomic Distribution of cadA6—A Novel Variant of a Cadmium Resistance Determinant Identified in Listeria spp.

Listeria monocytogenes is a pathogen responsible for severe cases of food poisoning. Listeria spp. strains occurring in soil and water environments may serve as a reservoir of resistance determinants for pathogenic L. monocytogenes strains. A large collection of Listeria spp. strains (155) isolated from natural, agricultural, and urban areas was screened for resistance to heavy metals and metalloids, and the presence of resistance determinants and extrachromosomal replicons. Of the tested strains, 35% were resistant to cadmium and 17% to arsenic. Sequence analysis of resistance plasmids isolated from strains of Listeria seeligeri and Listeria ivanovii, and the chromosome of L. seeligeri strain Sr73, identified a novel variant of the cadAC cadmium resistance efflux system, cadA6, that was functional in L. monocytogenes cells. The cadA6 cassette was detected in four Listeria species, including strains of L. monocytogenes, isolated from various countries and sources—environmental, food-associated, and clinical samples. This resistance cassette is harbored by four novel composite or non-composite transposons, which increases its potential for horizontal transmission. Since some cadAC cassettes may influence virulence and biofilm formation, it is important to monitor their presence in Listeria spp. strains inhabiting different environments.     

响应曲面法优化选择性浸出铜阳极泥中砷锑的研究

在硫酸化焙烧脱硒步骤前采用酸性氯化浸出脱除铜阳极泥中砷和锑。采用中心组合设计优化脱除铜阳极泥中砷和锑的实验参数。以硫酸浓度、盐酸浓度和反应温度为变量，砷和锑浸出率为响应值，建立高显著性的二次多项式模型和三维响应曲面。建立高显著性的二次多项式模型和三维响应曲面，以反映变量与响应值之间的关系。得到的较优条件为硫酸2.8mol/L、盐酸1.0mol/L、温度90℃，此条件下砷锑浸出率响应值分别为99.10％和80.00％，实际值分别为99.60％和80.07％。通过实验验证了模型的较优优区域,结果表明这些模型是可靠和准确的。     

酸性废水中As(Ⅲ)、Cu(Ⅱ)与铁粉的反应行为

在Fe-As(Ⅲ)-Cu(Ⅱ)-H₂O体系中, 研究了酸性废水中As(Ⅲ)、Cu(Ⅱ)与金属铁粉的反应行为, 考察了反应过程中As在气、液、固三相中的分配比。结果表明, As(Ⅲ)和Cu(Ⅱ)离子被Fe还原为单质As和Cu后, As、Cu进一步结合成Cu₅As₂等金属间化合物, 从而促进As(Ⅲ)沉淀反应的发生, 且无AsH3生成。在反应时间40min、铁粉过量系数1.2、溶液初始pH=0.0、温度40 ℃、Cu/As摩尔比1.0条件下, As在气、液、固三相中的分配比分别为0、20.7%和79.3%, 沉砷率为79.3%。     

焙烧方式对含砷金精矿中金、银浸出率的影响

某含砷金精矿中金矿物嵌布粒度较细,金主要以硫化物(黄铁矿、毒砂)包裹金形式存在。采用焙烧预处理-氰化浸出工艺,研究了一段焙烧、两段焙烧和添加剂焙烧对氰化浸出的影响。结果表明,采用常规一段、两段焙烧方式,金浸出率均未达到90%,银浸出率低于50%; 添加剂焙烧效果显著,在焙烧温度650 ℃、时间1.0 h、添加剂用量NaXY 100 kg/t+YC-1 20 kg/t的条件下,金浸出率达到93.56%,银浸出率达62.45%。     

沿海地区紫菜中总砷含量及砷形态分析

建立高效液相色谱-氢化物发生-原子荧光光谱(HPLC-HG-AFS)联用法分析紫菜中4种砷的形态。在优化仪器参数的基础上,采用正交试验法分析样品前处理中的酸浓度、萃取温度和超声时间对砷提取量的影响。当硝酸浓度0.15 mol/L、萃取温度80℃、超声时间1 h时,萃取效果最佳。对低、中、高3个水平进行方法验证,砷形态的回收率为84.0%~113.6%,精密度为1.3%~4.6%,结果显示,沿海地区的紫菜产品中总砷含量高,但有毒砷占比小。方法快速高效,可用于测定紫菜中砷形态的含量。