中药污染黄曲霉毒素B1检测分析

目的:了解中药污染黄曲霉毒素B₁(AFB₁)情况。方法:采用间接竞争酶联免疫吸附法(ELISA)对3 7种中药材和22批中成药污染AFB₁进行检测。结果:有34种中药材污染AFB₁,占92 % ;有19批中成药污染AFB1,占86%。结论:中药材和中成药都不同程度地污染AFB₁。     

中药中重金属元素检测方法的研究进展

中药材的重金属污染已成为影响中药质量、制约中药走向世界的一个瓶颈问题,因此准确检测中药重金属含量、合理制定中药中重金属限量标准已经刻不容缓,本文对目前国内外中药材中重金属的检测技术进行了综述。     

部分中药材及中药成方制剂中5种重金属及有害元素的测定

目的了解中药材及中药成方制剂中重金属污染情况,为相关标准制定提供数据支持。方法参照《中国药典》2015年版(四部),采用石墨消解,ICP-MS法测定43批中药材及18批中药成分制剂中铜、砷、镉、汞、铅的含量。结果与《药用植物及制剂外经贸绿色行业标准》相比,结果表明中药材及中药成方制剂均存在部分品种不同程度重金属超标现象,中药材中汞和铅超标现象较多,部分中药成分制剂存在汞严重超标的情况。结论中药材及中药成方制剂重金属污染问题仍然存在,需得到重视,建立合理的限度标准。     

白芍中的一种新的单萜苷

目的研究中药白芍的化学成分。方法用现代色谱分离方法进行化学成分分离,并通过理化性质和各种色谱学分析鉴定化合物的结构。结果从中药白芍中分离得到一种苷元与葡萄糖2位相连成苷的单萜苷类化合物白芍苷R₁。 结论白芍苷R₁是一新化合物。     

中药材规范化种植中重金属污染的防治

针对中药重金属污染这个中药生产过程中的难题,通过分析中药重金属污染的原因,结合中药GAP生产的实际,从生产基地的选择、土壤的修复及中药材生产管理等方面阐述了中药材规范化种植中重金属污染的防治方法.     

降低桑叶提取物中灰分的方法探讨

1前言中药提取物中的灰分及重金属是影响成品质量的重要指标之一。中药提取物中的灰分及重金属来源有两类,一类是中药材中生理性存在的无机离子.包括钠、钾、钙、镁、铁、氯化物和磷酸盐;另一类是中药材前处理过程中未除净的部分杂质(如:泥沙)。     

中药中重金属元素测定的研究进展

<正>我国中药以其丰富的资源、独特的疗效越来越受到世界各国的青睐和重视。与此同时,中药材中金属尤其是有毒重金属的含量超标问题也是当前国内外的热门的话题,是影响     

有机氯农药残留对中药污染问题探讨

通过对有机氯农药在中药中残留现状的分析探讨,阐述了中药材中残留农药的脱除方法,分析了有机氯农药的特点及残留原因。提示要生产出合格的中药材,建立绿色中药材生产基地才是根本的解决措施。     

UFLC法测定复方丹参片中三七皂苷R1、人参皂苷Rg1及Rb1

目的 探索建立超快速液相色谱（UFLC）法测定复方丹参片中三七皂苷R₁、人参皂苷Rg₁及Rb₁。方法 采用SHIMADZU Shim-pack XR-ODS Ⅲ（2.0 mm×75 mm, 1.6 μm）色谱柱;以乙腈-水作为流动相进行梯度洗脱;体积流量为0.4 mL/min;检测波长为203 nm;进样体积为3 μL。结果 三七皂苷R₁、人参皂苷Rg₁及Rb₁分别在0.025 7～0.257 0、0.101 2～1.012 0、0.104 4～1.044 0 μg与峰面积呈良好的线性关系,平均加样回收率分别为96.7%、98.1%、98.8%。结论 本方法在15min内可以将三七皂苷R₁、人参皂苷Rg₁及Rb₁有效分离,节省了大量人力和流动相的消耗,为中药的质量控制技术提供参考方法。     

100种常用药材重金属残留状况探析

目的：检测100味常用中药中重金属的含量,评价分析其重金属残留状况。方法：委托国土资源部武汉矿产资源监督检测中心（武汉综合岩矿测试中心）检测铅（ Pb）、镉（ Cd）、砷（ As）、汞（ Hg）四种重金属含量。结果：中药材中存在不同程度的重金属污染,总超标率为22%,镉（ Cd）、铅（ Pb）、砷（ As）、汞（ Hg）的超标率分别为19%、5%、2%、1%;单样本同一批次药材中存在2种重金属同时超标的现象;从药用部位看,根、根茎类药材占所有超标药物的50%;从地区分布看,华东和中南地区的超标数最多。结论：本次检测的药物经过重金属检测发现存在一定问题,需加强对中药材中有害元素的检测和控制,提高中药（材）的质量,保证临床用药安全。     

Fullerene derivatives induce premature senescence: A new toxicity paradigm or novel biomedical applications

Engineered fullerenes (C₆₀) are extensively used for commercial and clinical applications based on their unique physicochemical properties. Such materials have also been recognized as byproducts of many industrial activities. Functionalization of C₆₀ may significantly influence the nature of its interactions with biological systems, impacting its applications and raising uncertainties about its health effects. In the present study, we compared the bioimpact of two chemically modified fullerene derivatives, hexa carboxyl fullerene adduct (Hexa-C₆₀) and tris carboxyl fullerene adduct (tris-C₆₀) to pristine fullerene C₆₀ encapsulated with gamma (γ)-cyclodextrin C₆₀ (CD-C₆₀), using human cutaneous epithelial cells (HEK) to simulate possible applications and occupational dermal exposure route. We report, for the first time, the discovery of premature senescence as a potential endpoint of nanomaterial elicited biological effects, providing a new paradigm for nanoparticle-induced toxicity in human cells. Moreover, this response appeared to be functionalization specific, in that, only tris-C₆₀ induced senescence. We investigated key biological responses, such as cellular viability, intracellular ROS generation, cell proliferation and cell cycle responses. Our results indicate that the often observed ‘anti-apoptotic’ function of fullerene derivatives may be independent of their ‘ROS scavenging’ role as previously reported. We discovered that the tris-C₆₀-induced responses were associated with G₀/G₁ cell cycle arrest and cellular senescence. On further evaluation of the molecular mechanisms underlying the senescent response, a significant decrease in the expression levels of HERC5 was noted. HERC5 is a ubiquitin ligase of the HERC family and is implicated to be involved in innate immune responses to viral and bacterial infections.     

A longitudinal assessment of aflatoxin M1 excretion in breast milk of selected Egyptian mothers.

Aflatoxins are potent toxins and carcinogens which can be excreted in the milk of exposed lactating mothers mainly in the form of aflatoxin M(1) (AFM(1)). We previously evaluated the level and frequency of AFM(1) in breast milk in a group of Egyptian mothers attending the New El-Qalyub Hospital, Qalyubiyah governorate, Egypt. In this study, fifty of those women who were AFM(1) positive were revisited monthly for 12 months to assess the temporal variation in breast milk AFM(1). AFM(1) was detected in 248 of 443 (56%) samples. In a multilevel model of the data there was a highly significant (p<0.001) effect of month of sampling on the frequency of AFM(1) detection with summer months having the highest frequency (>80%) and winter months the lowest frequency (<20%) of detection. AFM(1) was observed most frequently in June [OR 63, 95% CI (7.6, 522)]. The level of AFM(1) detection also followed this seasonal pattern with highest mean level in July (64 pg/ml milk, range 6.3-497 pg/ml milk) and the lowest mean level in January (8 pg/ml milk, range 4.2-108 pg/ml milk). The duration of lactation [p=0.0035, OR=1.08, 95% CI (1.02, 1.13)], and peanut consumption [p=0.06, OR=1.69, 95% CI (0.9, 2.9)] also contributed to the model. The identification and understanding of factors determining the presence of toxicants in human milk is important and may provide a knowledge driven basis for controlling the transfer of chemicals to infants.     

Nimbolide and isonimbolide

Nimbolide 1, a potent molecule of biological significance, was isolated. Attempts were made to cleave the ether linkage in nimbolide using boron trifluoride etherate in the presence of tetrabutyl ammonium bromide so as to generate a ring-opened structure akin to azadirachtins, which are known to possess excellent antifeedant properties. However, a novel rearranged product was envisaged during the course of the reaction, which was determined as isonimbolide 2—a structural isomer of nimbolide through spectroscopic methods.     

In praise of H2O2, the versatile ROS,and its vanadium complexes

Hydrogen peroxide (H₂O₂) is generated in mitochondria in aerobic cells as a minor product of electron transport, is inhibited selectively by phenolic acids (in animals) or salicylhydroxamate (in plants) and is regulated by hormones and environmental conditions. Failure to detect this activity is due to presence of H₂O₂-consuming reactions or inhibitors present in the reaction mixture. H₂O₂ has a role in metabolic regulation and signal transduction reactions. A number of enzymes and cellular activities are modified, mostly by oxidizing the protein-thiol groups, on adding H₂O₂ in mM concentrations. On complexing with vanadate, also occurring in traces, H₂O₂ forms diperoxovanadate (DPV), stable at physiological pH and resistant to degradation by catalase. DPV was found to substitute for H₂O₂ at concentrations orders of magnitude lower, and in presence of catalase, as a substrate for user reaction, horseradish peroxidase (HRP), and in inactivating glyceraldehyde-3-phosphate dehydrogenase. superoxide dismutase (SOD) -sensitive oxidation of NADH was found to operate as peroxovanadate cycle using traces of DPV and decameric vanadate (V₁₀) and reduces O₂ to peroxide (DPV in presence of free vanadate). This offers a model for respiratory burst. Diperoxovanadate reproduces several actions of H₂O₂ at low concentrations: enhances protein tyrosine phosphorylation, activates phospholipase D, produces smooth muscle contraction, and accelerates stress induced premature senescence (SIPS) and rounding in fibroblasts. Peroxovanadates can be useful tools in the studies on H₂O₂ in cellular activities and regulation.     

Prediction of volume of distribution in preclinical species and humans: application of simplified physiologically based algorithms

1. The present study was aimed at developing simplified physiologically based semi-mechanistic algorithms to predict V_ss and interspecies scaling factors to predict tissue-K_ps which require minimum input parameters, diminish the computing complexity and have better predictability.

2. V_ss of 86 structurally diverse compounds in preclinical species and 27 compounds in humans were predicted using only lung- and muscle-K_p as inputs. Interspecies scaling factor (s) were developed based on fold-differences in individual tissue lipid contents, relative organ blood flow: relative organ weight ratio between two species. Tissue-K_ps were predicted for 34 compounds using the newly developed interspecies scaling factors.

3. The predicted-to-experimental V_ss values for all the 113 compounds was 1.3?±?0.9 with 83% values being within a factor of two. The tissue-K_ps in rat, dog and human were predicted using experimental tissue-K_p data in rodents and interspecies scaling factors and here also, 83% of tissue-K_ps were within two-fold of the experimental values.

4. In conclusion, simplified physiologically based algorithms have been developed to predict both volume of distribution and tissue-K_ps, in which required input parameters as well as computing complexity have been noticeably reduced.

     

维生素D原体浓度对它的光异构反应的影响

目的：研究乙醇溶液中维生素D原体浓度对它的光异构反应产物产率的影响。方法：用两种紫外光激发光源光照不同浓度的维生素D原体乙醇溶液，使用正相HPLC系统定量测定主要光异构物在溶液中的浓度。结果：数据表明，随维生素D原体浓度的增加，速甾醇产率减少，而光甾醇产率明显增加。维生素D前体产率变化，与所用的激发光源有关。结论：维生素D原体浓度对其光异构反应产物产率的影响较大，特别对速甾醇和光甾醇，利用光自吸收效应有助于设计光化学法合成药物及制备高产率的光异构产物。     

Serotonergic approaches in the development of novel antipsychotics

Schizophrenia is a chronic, debilitating neuropsychological disease characterised by positive, negative, and cognitive deficits. In recent years, new pharmacological treatment strategies have been developed to treat the sequalae of schizophrenia based upon more selective receptor activity profiles in the hope that treatment efficacy can be increased without inducing the side-effect profiles seen with current available therapies. One such strategy involves the development of combined (partial) 5-HT_1A agonists and D₂ receptor (partial) antagonists such as bifeprunox, SLV313, F15063 and SSR-181507 in an attempt to increase therapeutic efficacy of all symptom domains whilst alleviating adverse side effects. Other novel drugs including SLV310 and SLV314 combine selective serotonin reuptake inhibition (SSRI) functionality with D₂ receptor antagonism in an attempt to not only improve schizophrenic symptoms, but to also relieve other affective disorders intricately linked with the disorder. The main scope of this review will evaluate the major preclinical and clinical pharmacological findings concerning the aforementioned strategies and pharmacological agents, and compare their therapeutic potential with currently available antipsychotics; however, recent developments at other emerging serotonergic targets such as 5-HT_2C, 5-HT₆ and 5-HT₇ receptors will also be considered.     

Integrin antagonists as therapeutics for inflammatory diseases

Integrins are a family of heterodimeric cell surface receptors that mediate adhesion events crucial to cellular migration, proliferation and activation. Although critical to a normal immune response, integrins can also facilitate the progression of many inflammatory and autoimmune disorders. As such, they have attracted the attention of the pharmaceutical industry. Several humanised monoclonal antibodies directed against integrin targets have proven to be successful in clinical trials and have been approved for use in humans. This has not only resulted in effective therapies for patients, but also has provided important proof-of-concept studies for the development of small-molecule antagonists. This review focuses on those integrin subclasses that are being evaluated for their potential role in pulmonary, dermatological, gastrointestinal or rheumatic diseases. These include the α₄ and β₂ integrins, as well as an emerging group of targets from the collagen-binding family of integrins. Interfering with integrin signalling pathways represents a future area of interest. The rationale for pursuing these targets, as well as the drugs presently under development, are discussed.     

Urinary biomarkers of aflatoxin exposure in young children from Egypt and Guinea.

Aflatoxins are a major risk factor for hepatocellular carcinoma (HCC), and thus understanding the pattern of aflatoxin exposure in different regions is important in order to develop targeted intervention strategies. Given the early onset of HCC in many countries early life exposures may be important. This study investigated aflatoxin exposure in Egyptian children (n=50, aged 1-2.5 years) by assessing urinary aflatoxin metabolite (AFM(1), AFB(1), AFB(2), AFG(1), AFG(2)) levels. Samples from Guinean children (n=50, aged 2-4 years) were analyzed in parallel providing a comparison to a region of established frequent aflatoxin exposure. Aflatoxins were isolated from urine using C18-cartridges followed by immunoaffinity clean-up, and quantified by HPLC with fluorescence detection. Overall aflatoxins were less frequently present in Egyptian (38%) than Guinean urine samples (86%) (p<0.001), which was particularly related to differences in detection rates of AFM(1) (8% compared to 64%, respectively, (p<0.001)). For AFM(1) the geometric mean level in Guinea (16.3 pg/ml; 95% CI: 10.1, 26.6 pg/ml) was 6-fold higher (p<0.001) than in Egypt (2.7 pg/ml; 95% CI: 2.5, 2.8 pg/ml). Urinary aflatoxins from healthy children in these two regions have not previously been reported, and exposure appears modest in Egypt compared to Guinea. These data suggest that measures to reduce aflatoxin exposure in both regions are important, though particularly in Guinea.