Sex versus sweet: Opposite effects of opioid drugs on the reward of sucrose and sexual pheromones.

Endogenous opioids mediate some reward processes involving both natural (food, sweet taste) and artificial (morphine, heroin) rewards. In contrast, sexual behavior (which is also reinforcing) is generally inhibited by opioids. To establish the role of endogenous opioids for a newly described natural reinforcer, namely male sexual pheromones for female mice, we checked the effects of systemic injections of the general opioid antagonist naloxone (1-10 mg/kg) and the agonist fentanyl (0.1- 0.5 mg/kg) in a number of behavioral tests. Naloxone affected neither the innate preference for male-soiled bedding (vs. female-soiled bedding) in 2-choice tests nor the induction of place conditioning using male pheromones as rewarding stimuli, although it effectively blocked the preference for consuming a sucrose solution. In contrast, fentanyl inhibited the preference for male chemosignals without altering sucrose preference. These results suggest that, in macrosmatic animals such as rodents, opioidergic inhibition of sexual behavior might be due, at least partially, to an impaired processing of pheromonal cues and that the hedonic value of sweet-tasting solutions and sexual pheromones are under different opioid modulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

60 Coγ射线辐照五种常见渔药在水溶液中降解作用的研究

本文采用0—10kGy的60Coγ射线对水溶液中的磺胺二甲基嘧啶、噁喹酸、氯霉素、呋喃唑酮、土霉素进行处理,并测定了环境的酸碱性、空气、温度对辐照降解率的影响。结果表明,60Coγ射线辐照处理能显著降解五种常见渔药在水中的残留,吸收剂量越大,渔药的降解率越高;初始浓度越低,越有利于渔药的去除。当吸收剂量为8kGy时,五种渔药(初始浓度100mg/L)的降解率均达到90%以上,酸碱性和空气环境对不同种类的渔药降解率影响有一定的差异,降低温度对渔药降解有明显抑制作用。     

Decomposition of diclofenac by solar driven photocatalysis at pilot plant scale

Pilot plant experiments applying solar titanium dioxide photocatalysis and solar photo-Fenton treatment at different pH and iron concentrations with an initial diclofenac concentration of 50 mg L⁻¹ are described.

In preliminary experiments absence of hydrolysis and slow photolysis under solar irradiation of diclofenac solutions were observed. Solar photo-Fenton treatment with freshly precipitated iron at pH around 7 showed first order kinetics, the reaction taking place on the surface of the iron precipitate. Simultaneous oxidation, precipitation and re-dissolution processes of diclofenac governed photo-Fenton decomposition kinetics at pH 2.8. The use of different iron concentrations (0.03–0.75 mM) showed no influence on the reaction rate in a neutral medium due to reactor geometry. Similar behaviour (no influence of iron concentration) was observed at pH 2.8, due to precipitation problems. A pH of around 4, close to the pK_a of diclofenac, showed promising results, partly overcoming both iron and diclofenac precipitation. Solar titanium dioxide photocatalysis with Degussa P-25 followed first order kinetics and no precipitation or adsorption occurred.

Decomposition of diclofenac took around 100 min under all photo-Fenton treatment conditions employed. Decomposition by titanium dioxide photocatalysis took about 200 min. In photo-Fenton treatment, hydrogen peroxide consumption to diclofenac decomposition was about 80–110 mM at pH 2.8 and 40 mM in the other two treatments (neutral pH and pH = 4).     

The Role of Low-Energy Electron Interactions in cis-Pt(CO)2Br2 Fragmentation

Platinum coordination complexes have found wide applications as chemotherapeutic anticancer drugs in synchronous combination with radiation (chemoradiation) as well as precursors in focused electron beam induced deposition (FEBID) for nano-scale fabrication. In both applications, low-energy electrons (LEE) play an important role with regard to the fragmentation pathways. In the former case, the high-energy radiation applied creates an abundance of reactive photo- and secondary electrons that determine the reaction paths of the respective radiation sensitizers. In the latter case, low-energy secondary electrons determine the deposition chemistry. In this contribution, we present a combined experimental and theoretical study on the role of LEE interactions in the fragmentation of the Pt(II) coordination compound cis-PtBr₂(CO)₂. We discuss our results in conjunction with the widely used cancer therapeutic Pt(II) coordination compound cis-Pt(NH₃)₂Cl₂ (cisplatin) and the carbonyl analog Pt(CO)₂Cl₂, and we show that efficient CO loss through dissociative electron attachment dominates the reactivity of these carbonyl complexes with low-energy electrons, while halogen loss through DEA dominates the reactivity of cis-Pt(NH₃)₂Cl₂.     

Applications of Catalytic Asymmetric Sulfide Oxidations to the Syntheses of Biologically Active Sulfoxides

Optically active sulfoxides are important compounds for medicinal and pharmaceutical chemistry. Driven by the increasing demand for efficient, selective and environmentally friendly industrial processes, several catalytic methodologies have been developed in recent years for the stereoselective oxidation of sulfides for the preparation of biologically active sulfoxides. Both small‐scale approaches to the problem as well as some large‐scale applications that are already in industrial use are described in this review.     

铂类药物神经毒性的药物基因组学研究进展

铂类药物广泛的应用于肺癌、大肠癌、卵巢癌、乳腺癌等多种癌症的治疗。然而,铂类药物的疗效往往由于严重的毒副反应,尤其是神经毒性而受到限制。铂类药物的神经毒性存在较大的个体性差异,其药物代谢相关基因的遗传变异是导致神经毒性个体差异的重要原因之一。本文就铂类药物转运体、药物代谢酶和DNA修复酶等相关基因的遗传多态性与铂类药物神经毒性之间的相关性作一综述。     

Nanoarchitectonics: Complexes and Conjugates of Platinum Drugs with Silicon Containing Nanocarriers. An Overview

The development in the area of novel anticancer prodrugs (conjugates and complexes) has attracted growing attention from many research groups. The dangerous side effects of currently used anticancer drugs, including cisplatin and other platinum based drugs, as well their systemic toxicity is a driving force for intensive search and presents a safer way in delivery platform of active molecules. Silicon based nanocarriers play an important role in achieving the goal of synthesis of the more effective prodrugs. It is worth to underline that silicon based platform including silica and silsesquioxane nanocarriers offers higher stability, biocompatibility of such the materials and pro-longed release of active platinum drugs. Silicon nanomaterials themselves are well-known for improving drug delivery, being themselves non-toxic, and versatile, and tailored surface chemistry. This review summarizes the current state-of-the-art within constructs of silicon-containing nano-carriers conjugated and complexed with platinum based drugs. Contrary to a number of other reviews, it stresses the role of nano-chemistry as a primary tool in the development of novel prodrugs.     

Stability study of veterinary drugs in standard solutions for LC-MS/MS screening in food

A study on stability of veterinary drugs in standard solutions stored at ?80°C and at ?20°C was conducted over 1 year. Data were acquired on 152 individual stock standard solutions and also on 15 family mixes and 2 working standard solutions. All solutions were prepared, stored and compared 1 year later against freshly prepared ones by LC-MS/MS. A statistical analysis was performed to set the acceptability criteria, taking into account the variability of standard preparations. In individual stock standard solutions stored at ?80°C (12 months) and ?20°C (9 months), stability was demonstrated for 141 and 140 out of 152 compounds, i.e. for 92% and 93% of compounds, respectively. Drugs were even more stable when solubilised in either diluted family mixes or working standard solutions, with more than 99% and 94% of compounds found unaltered when stored at ?80°C and at ?20°C, respectively. In mixes, beta-lactams from the cephalosporin (cefadroxil and cephalexin) and penicillin (amoxicillin and ampicillin) families were found to be the least stable compounds when stored at ?20°C (6 months), necessitating storage at ?80°C to achieve a 1-year shelf life. The study also evidenced solubility issues for two sulfonamides (sulfadiazine and sulfamerazine) in methanol-based solutions. An independent stability study conducted by a second laboratory confirmed the 1-year stability of 3 family mixes—quinolones, sulfonamides and tetracyclines.     

Sensitivity enhancement of aminoglycosides in hydrophilic interaction liquid chromatography with tandem mass spectrometry by post-column addition of trace sodium acetate in methanol

The development of a sensitive and accurate analytical method for monitoring aminoglycosides in food, environmental, and clinical samples is needed for many purposes. This study found that the responses of sodiated and protonated aminoglycosides in hydrophilic interaction chromatography with tandem mass spectrometry were enhanced upon addition of sodium acetate in methanol (5 mg L^?1 at a flow rate of 0.2 mL min^?1) as a post-column reagent. The sensitivities of sodiated spectinomycin, kanamycin, gentamicins, neomycin, and amikacin were significantly higher than those of the protonated molecules. Streptomycin and dihydrostreptomycin only formed protonated molecules, suggesting the preferential ionisation of the guanidine moieties in these aminoglycosides. The limits of quantification of these aminoglycosides were 0.19–2.5 ng mL^?1. Notably, this is the first quantification of aminoglycosides that uses the sodiated molecules. The enhancement technique enables us to eliminate a concentration step from the clean-up process from food samples. We also proposed a rapid analytical method for residual aminoglycosides in milk and meat samples; validation showed good accuracy and precision of this method at the Japanese maximum residual limits of aminoglycosides (40–500 µg kg^?1). The application of this method to contaminated bovine tissues revealed remarkably high residual levels of kanamycin. This technique will be useful for the sensitive detection of aminoglycosides not only in food, but also in environmental samples and human plasma.     

基于我国动物性食品中禁限用兽药使用规定的食源性兴奋剂种类浅析

本文通过对GB 31650—2019《食品安全国家标准 食品中兽药最大残留限量》允许使用的兽药、农业农村部第250号等系列公告禁用兽药以及世界反兴奋剂机构（World Anti-Doping Agency,WADA）《WADA禁用清单国际标准（2021年）》中11 个大类315 种禁用物质和监控程序涉及的物质进行对比分析,运用Python的第三方函数库对比算法,发现《WADA禁用清单国际标准（2021年）》中蛋白同化制剂、β2-激动剂、糖皮质激素类、刺激剂、利尿剂和掩蔽剂以及肽类激素6 个大类的33 种物质与我国动物性食品兽药使用规定相应种类重合。同时对大型赛事防控食源性兴奋剂种类进行分析比较,发现有蛋白同化制剂、β2-激动剂、β-阻断剂、利尿剂和掩蔽剂、刺激剂、糖皮质激素类6 个大类39 种药物与WADA禁用药物相同;有蛋白同化制剂、β2-激动剂、利尿剂和掩蔽剂、刺激剂、糖皮质激素类5 个大类25 种药物与农业农村部禁限用兽药种类相同;与WADA禁用药物和农业农村部禁限用兽药种类均相同的有蛋白同化制剂、β2-激动剂、利尿剂和掩蔽剂、刺激剂、糖皮质激素类5 个大类19 种兴奋剂。以上分析结果为进一步明确食源性兴奋剂种类及范围提供工作思路,为加强重大体育赛事动物性食品中食源性兴奋剂的防控工作提供参考。