Solid-phase microextraction for flavor analysis in Harari Khat （Catha edulis） stimulant

This research examined the typical flavor compounds in the commonest type of Khat called Harari Khat grown in the region of Ethiopia.Twenty-eight compounds, which includes 1,2-Propanedione,1-Phenyl,Hexanol,Hexanal compounds,Limonene, Benzaldehyde with other flavors, were extracted by polydimethylsiloxane at room temperature for 30min from Khat samples,and identified by solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS).This method needs no organic solvents and required minimal sample.

Khat(Catha Edulis) as a possible cause of autoimmune hepatitis

AIM:To investigate the potential role of khat in triggering auto immune hepatitis.METHODS:Patients with a history of khat use and acute hepatitis were identified using the computer database in the hepatology department at the Royal Hallamshire Hospital.They were then assessed for probability of having autoimmune hepatitis using the revised autoimmune hepatitis scoring criteria.RESULTS:Six patients were identified.All of them had presented with acute hepatitis on a background of khat.All were male and five of these patients were of Somali origin,while one patient was from Yemen.The patients were given points on the modified autoimmune hepatitis score which is based on their liver enzymes,autoimmune screen,exclusion of viral hepatitis alcohol and drugs,immunoglobulin levels and liver histology.The patients were given a score of-4 for khat use due to its potential to cause drug induced liver injury.Five of these patients scored between 10 and 15 points,placing them in the probable group for having autoimmune hepatitis.All of these patients were treated with prednisolone and demonstrated a good response to immunosuppression.CONCLUSION:One possibile cause of hepatotoxicity with khat could be via triggering of autoimmune hepatitis in a genetically susceptible individual.Further studies are needed for confirmation.

Cryptogenic liver cirrhosis diagnosed in pregnancy and khat consumption

We report a case of cryptogenic liver cirrhosis likely due to khat consumption diagnosed in the setting of chronic hypertension and giving the appearance of atypical superimposed preeclampsia.

The Coffee-Khat Interface in Eastern Ethiopia： A Controversial Land Use and Livelihood Change Scenario

The aim of the study was to assess the current trend of coffee and khat production as well as the subsequent land use and livelihood change scenario in the area. By so doing, the study tried to identify the impact of both commodities on the socio-economic well being of both the rural and urban communities. These areas, with regard to this particular study, cover all parts of the East and West Harerghe zones of the Oromiya National Regional State, the coffee and khat growing parts of the Somalia and Harari National Regional States as well as the Dire-Dawa Administration Council in Ethiopia. In so doing, the article is partly based on the first hand information gathered especially by the first author during his assigned mission in March 2002 by the institution he was then working for, i.e., Institute of Biodiversity Conservation （IBC）, Ethiopia. The study indicates that on top of other biotic and abiotic stress, ever since the first official appearance of coffee berry disease （CBD） in around 1973, there has been a huge shift in land use from coffee to khat with over 63% of the total coffee land being uprooted and converted into the later. As such, the study points out the fact that if the trend continues to keep unabated, it is very likely that the genetic base of the unique coffee type in the area will be similarly further endangered. On the other hand, the study states that the existing reality on the ground is entirely different from what appears to be true in the development or policy theories. Because of the absence of basic and sustainable options for CBD and other biotic and abiotic hazards prevailing in the area, including on other crops, as well as the absence of a fair trade price for their unique quality coffee at international level, farmers have been obliged to switch and increasingly rely on khat as an alternative God blessed commodity given to their locality. Thus, even though there are growing controversies and/or hasty health and social connotations against khat, it is very unlikely to recover the situation back to the origin so easily, as farmers have already gone far away changes in their way of farming and socio-economic set up, or as stated above in their land use and livelihood circumstances. Before a long-term solution is obtained to solve the multifaceted environmental, social and economic problems and explore other sustainable and socially inclusive alternatives, reckless and hasty restrictions and/or impositions can only be unjustifiable, as they will cause overall socio-economic difficulties to all the communities therein.

Khat chewing practice and its perceived health effects among communities of Dera Woreda, Amhara region, Ethiopia

Introduction: Khat chewing is believed to be rapidly increasing worldwide. Worldwide, it is estimated that 10 million people consume khat daily. Khat chewing practice renders certain influence on physical and psychological well being of the community and it can cause more serious adverse psychiatric, cardiovascular, dental and gastrointestinal effects. The recent sharp increase in khat consumption may not only affect the health of individuals but could also have serious socio-economic consequences. This study was conducted to assess prevalence of khat chewing practice, its associated factors and perceived health effects among communities in Dera woreda, Amhara region, Ethiopia 2013. Methods: Community-based cross-sectional study was conducted by using both quantitative and qualitative method of data. The sample size for quantitative was determined by using single population proportion formula and the households were selected by systematic sampling method and in the selected household, one respondent was selected by lottery among members of household aged 15 years and above. Data were collected by means of a pretested questionnaire;analysis was carried out using SPSS version 16. For the qualitative part ten in-depth interviews were conducted on purposely selected individuals and sample size for this method was determined through continuing to interview participants until no new information was obtained. Results: The response rate was 98.3%. Current prevalence of khat chewing practice was 17%. Males were more likely to chew khat (AOR, 18.53;95%CI, 7.20-47.66) compared to females. Muslims were more likely to chew khat (AOR, 4.34;95%CI, 2.07-9.11) compared to Orthodox Christians. Respondents who had family member chewing khat were more likely to chew khat (AOR, 2.67;95%CI, 1.15-6.21) compared to family member without a chewer. Among all the respondents, 92.8% perceived the health effects of khat chewing practice. Respondents who did not perceive health effect of khat were 5 times more likely to chew khat (AOR = 5.10, 95%CI;1.64-15.5) compared to those who perceived health effect of khat. Conclusions: The prevalence of khat chewing practice was 17% with high proportion of the khat chewers found in the urban setting. Sex, religion, residence, family chewing habit and perceived health effect were significantly associated factors with khat chewing practice. In this study 92.8% of the respondents perceived that khat chewing practice had harmful effects on health and the perceived health effects reported were sleeping disorder, hallucination, tooth staining, anxiety, and loss of appetite, depression, constipation, gastritis, hypertension and psychosis.

The Reproductive and Thyroid Hormonal Profile of Khat (Catha Edulis) Chewers

The effects of khat on the hormonal levels have been established;however, the effects on human beings are controversial. The aim of our study was to investigate the possible effects of khat on the levels of serum thyroid hormones, testosterone, estradiol (E2), prolactin and cortisol in men. A total of 50 blood samples were collected from healthy males who referred to chew khat for more than 10 years and analyzed for the above hormones. The results were compared to the hormonal levels of 35 non khat chewers. Chewing khat causes significant increases in the testosterone (P < 0.03), prolactin (P < 0.05), E2 (P < 0.00005), FT3 (P < 0.04), and TSH (P < 0.05) levels. No significant differences were found in the serum level of FT4 between the two groups. The level of cortisol were significantly lower (P < 0.001) in the khat chewers group compared to the control group. This study suggests that khat chewing can cause reduction in the cortisol level, which may cause increases of testosterone, prolactin and E2. In addition, chewing khat increases the level of TSH and FT3 serum levels. Therefore, khat may contribute to the relevant disorders caused by abnormal levels of the studied hormones in the people who are chewing

Impact of Khat Production and Marketing on the Livelihood of Smallholder Households in Ethiopia

Khat, Ethiopia’s largest export cash crop, is the backbone of the Ethiopian economy. However, Ethiopia has not yet fully promoted its position as the utmost producer and exporter of khat in a global market because of its different policy discourses and illegal trade issues on khat production. The life of many smallholder households relies on khat production and its marketing in a country. Hence for thus, some information has been gathered on different aspects of khat with the objectives of reviewing khat’s impacts on the livelihood of smallholder farmers, its production status, and marketing constraints in Ethiopia. To review these objectives, data from CSA, and different published materials on khat were used. According to the review, khat production has a positive impact on securing household food insecurity and improving the livelihood status of smallholder farmers, and the largest foreign exchange-earning cash crops. However, it is exploited almost in all parts of a country’s government policy discourse on khat production and its trade legal issues, lack of infrastructure, zero access to extension services, zero tangible value addition, inadequate technology transfer, and research, and price volatility because of product perishability behavior are among major constraints threatened in khat production in Ethiopia. Its vulnerable and corrupted marketing system, zero market promotion and political dichotomy, long market chain, chronic market information, and unfair price were reported by different scholars as major problems of khat marketing in Ethiopia. From these probs: The government should analyze why and its impact on khat production discourse policy on the livelihood of smallholder households and overlook positive policy proclamation. Encouraging research and technology transfer to transform products into manufacturing industries, enhancing infrastructural and institutional facilities, and improving khat production product technologies through development, and khat production agribusiness industry transformation, institutionalizing its marketing arrangement and other related agronomic practices are among the major recommendations to forward so.

Studies on the Effects of Extracts of Fresh Khat/Catha edulis Leaves on the Oxidation of Niger Seed Oil

The methanolic extract of the fresh leaves of khat/Catha edulis was investigated using established procedures for its phytochemical constituents and effect on lipid oxidation.The phytochemical analysis revealed the presence of alkaloids,tannins,phenols,and flavonoids.The effects of the extract on oxidation of locally produced edible NSO(niger seed oil)was assessed through the measurement of peroxide value,iodine value and conjugated diene concentration for a period of sixteen days.Control setup involving NSO without the extract was also kept for the same period of time under similar conditions.It was observed that the peroxide value and conjugated diene value of the oil containing varying concentrations of the extracts of khat leaves increased significantly,relative to the control,showing that the extract of the khat leaves promoted deterioration of the oil.In a similar manner,the iodine value of NSO with and without added khat leaves extract was assessed.It was observed that the iodine value of the oil containing the khat leaves extract decreased more rapidly than the control,suggesting that the double bonds in the fat constituting the oil were diminished by the extract of the khat leaves.It is thus inferred from the present study that methanolic extract of fresh khat leaves leads to deterioration of NSO.It can also be suggested from the results of the present investigation that the health problems khat chewers face may be related to the oxidative damaging effects of these leaves exert on biomolecules found in the body.

Molecular docking of amphetamine,cathine and cathinone with dihydrofolate reductase:a computational analysis of inhibition of dihydrofolate reductase by khat alkaloids

Interaction of amphetamine,cathine and cathinone with the enzyme dihydrofolate reductase was studied by molecular docking using AutoDock 4.2 as the docking software application.AutoDock 4.2 software serves as a valid and acceptable docking application to study the interactions of small compounds with proteins.Interactions of amphetamine,cathine and cathinone with dihydrofolate reductase were compared to those of methotrexate,a known inhibitor of the enzyme.The calculated free energy of binding(ΔG binding)shows that the three ligands(ΔG=-6.87 to-7.21 kcal/mol;Ki=9.15 to 5.18μM)bind with affinity slightly lower than methotrexate(ΔG=-8.78 kcal/mol;Ki=363 nM).Binding interactions of the three ligands with active site residues of the enzyme are also predicted.All the ligands appear to bind in a similar conformation making extensive VDW contacts in the active site of the enzyme.Hydrogen bonding and pi-pi interaction with key active site residues is also observed.Thus,a probable inhibition of dihydrofolate reductase by khat alkaloids can be explained on the basis of this in silico binding and khat alkaloids can be considered as potential lead compounds in the development of new inhibitors of dihydrofolate reductase which is a potential target of anti-cancer drugs.The results of these studies can serve as a starting point for further computational and experimental studies.

Khat的滥用及其管理

本文回顾了国际社会近年来就Khat(恰特草)的药理作用及药代动力学、滥用形势和特点、药物依赖性、对Khat的管制等问题开展的研究及发表的文献。文献指出Khat使用主要在非洲和阿拉伯半岛部分国家和地区较为流行,在欧洲等地区也有一定使用人群;Khat使用可造成一系列的躯体和精神健康问题,但其与部分身心危害的因果关系需要进一步的研究加以验证;Khat具有一定的药物依赖潜力,需开展深入研究对其依赖性和成瘾特征加以探讨,为Khat管制决策提供科学依据。

恰特草中精神活性成分及其提取检测研究进展

恰特草是常见的毒品原植物之一,国内常出现在走私案件中。其主要精神活性成分为卡西酮和去甲伪麻黄碱,由于实验材料的特殊性,国内对于恰特草中化学成分及其代谢途径、检测方式研究不足,且存在干燥恰特草中只含痕量或不含卡西酮的论断。国外研究则较为充分,提出恰特草中的苯烷胺类生物碱的含量在不同产地、不同品种以及植株的不同部位均存在差异,指出精神活性成分在恰特草植株和人体中的主要代谢途径;通过植株干燥实验证明,无论以何种方式干燥的恰特草均能利用气相色谱及其他色谱联用技术检测出卡西酮、去甲麻黄碱和去甲伪麻黄碱成分。本文通过总结国内外对恰特草中精神活性成分的相关研究,为恰特草的检材送检和理化检验提供参考,并提出以下推论:案件中获得的恰特草中卡西酮的分解更多发生在新鲜恰特草的保存阶段而不是干燥阶段;干燥恰特草中的卡西酮应以非游离的状态稳定存在;可能存在其他成分直接或间接增强了恰特草的精神活性作用。

Petrography, Geochemistry and U-Pb Detrital Zircon Dating of the Clastic Phu Khat Formation in the Nakhon Thai Region, Thailand: Implications for Provenance and Geotectonic Setting

The purpose of this paper is to determine the provenance and tectonic setting of the Phu Khat Formation and get a better understanding of the tectonic evolution of the Nakhon Thai region using the petrography and whole-rock geochemistry integrated with the U-Pb detrital zircon dating. The sandstone of the Late Cretaceous to Early Tertiary Phu Khat Formation is chiefly characterized by unsorted texture and highly unstable volcanic lithic fragments. The formation overlies unconformably on a high textural and mineral maturity of clastic sandstone of the Late Cretaceous Khao Ya Puk Formation. Geochemically, the tectonic setting discrimination（K2O/Na2O-SiO2, Al2O3/SiO2-Fe2O3＋Mg O, and Th-Sc-Zr/10） and the petrography indicate that the Phu Khat Formation was accumulated in a passive margin tectonic setting which is the same as the Khao Ya Puk Formation but with a different depositional environment. The plots of geochemical provenance discrimination（La/Th-Hf, Th/Sc-Zr/Sc, Eu anomaly Eu/Eu＊ 0.42 to 0.74） and the petrography reveal that the provenance of the Khao Ya Puk Formation is mainly recycled sedimentary rocks while the Phu Khat Formation consists primarily of recycled sedimentary rocks associated with minor felsic volcanic rocks from the old continental island arc of the uplifted either western or eastern continental terranes or both. However, the U-Pb detrital zircon dating indicates a unique provenance of the Phu Khat Formation from the terrane west of the Nakhon Thai region where the volcanic continental arc is active predominantly in the Middle to Late Triassic. The results indicate that while the Phu Khat Formation was accumulated in Nakhon Thai region, the western terrane was uplifted by reactivation of the preexisting structure probably since the Maastrichtian time to be the source area of sediments. Meanwhile, the eastern terrane（mainly Loei-Phetchabun fold belt） had not been uplifted probably until, the accumulation of the Phu Khat Formation terminated. Subsequently, the whole region began to uplift forming a high mountainous area since the Ypresian time when the Greater India collided with the Eurasia.

高效液相色谱-四极杆/飞行时间质谱的源内裂解-多级质谱法解析干燥恰特草中卡西酮类生物碱成分

本研究基于高效液相色谱-四极杆/飞行时间质谱(HPLC-Q-TOF MS)的源内裂解-多级质谱法,发现并解析了恰特草中未知卡西酮类生物碱成分。将恰特草粉碎后,采用0.05 mol/L HCl水溶液提取,二氯甲烷、NaOH水溶液净化,ZORBAX Eclipse Plus Phenyl-Hexyl色谱柱(3.0 mm×100 mm×1.8μm)以0.1%甲酸水(A)-乙腈(B)为流动相进行梯度洗脱。在一级质谱全扫描模式下,通过卡西酮类生物碱的源内裂解特征实现未知卡西酮类生物碱成分的筛查;在目标离子采集模式下,基于未知卡西酮类生物碱成分的多级质谱裂解规律推测其分子结构。结果表明,该方法可实现恰特草中未知生物碱成分的筛查和解析,共识别出甲卡西酮、乙卡西酮和2-氨基-1-苯基-1-丁酮等3种卡西酮类生物碱成分,并采用标准物质对甲卡西酮和乙卡西酮进行确证,但由于缺乏相应的标准物质,2-氨基-1-苯基-1-丁酮有待进一步确证。本工作为恰特草中精神活性成分的进一步研究提供指引,为其他领域未知化合物的解析提供参考。

溶剂萃取-高效液相色谱-四极杆飞行时间质谱法快速提取检测干燥恰特草中5种生物碱成分

恰特草是一种常见的毒品原植物,卡西酮、去甲伪麻黄碱、去甲麻黄碱是其主要的精神活性成分。筛查发现恰特草中还存在具有较强精神活性作用的甲卡西酮和乙卡西酮成分。国内关于恰特草中生物碱成分的提取检测研究较少,国外也未见恰特草中甲卡西酮和乙卡西酮成分的研究。本研究通过优选提取溶剂种类、优化净化条件和色谱-质谱条件,利用0.05 mol/L的盐酸水溶液提取,二氯甲烷和1 mol/L的NaOH水溶液净化,再利用乙腈萃取,采用ZORBAX Eclipse Plus Phenyl-Hexyl色谱柱(100 mm×3.0 mm,1.8μm)分离,以0.1%甲酸水溶液-乙腈为流动相梯度洗脱,电喷雾双喷离子源(Dual AJS ESI)正离子模式下电离,四极杆飞行时间质谱仪目标离子采集模式(Target MS/MS)检测,外标法定量,建立了溶剂萃取-高效液相色谱-四极杆飞行时间质谱法提取检测干燥恰特草中5种生物碱成分的方法。结果表明,5种生物碱成分在各自的线性范围内线性关系良好,相关系数(r^(2))≥0.9976,检出限为0.08~0.75μg/L,定量限为0.25~2.50μg/L。2份生物碱含量差异较大的恰特草中5种生物碱成分的加标回收率为90.7%~105.2%,实验仪器精密度为0.5%~2.3%,日内方法精密度为1.0%~2.5%,日间方法精密度为1.3%~3.3%。该方法净化效果好,定量准确,灵敏度高,重复性好。利用该方法对国家林业局森林公安司法鉴定中心受理的15份恰特草相关案件中的检材进行检验,均检出5种生物碱成分,能够满足恰特草的理化检验鉴定要求,为恰特草中未知精神活性成分的发现和研究提供参考和指引。

基于HJ-1B数据的积雪制图NDSI阈值分析——以祁连山积雪为例

环境减灾卫星是我国于2008年发射的用于环境与灾害监测预报的小卫星星座,相对于气象卫星传感器,其空间分辨率有了较大提高.以祁连山积雪为研究对象,利用环境减灾卫星HJ-1B星开展积雪提取监测研究,分别对不同区域、不同高程的积雪区进行积雪提取,以同时期Landsat ETM+影像中提取的积雪面积为标准,对环境减灾卫星NDSI阈值的选取进行研究分析,以确定适合于HJ-1B提取积雪的阈值;同时利用不同季节的HJ-1B积雪数据进行验证,用Kappa检验阈值的精度.研究表明:HJ-1B积雪制图的阈值为NDSI≥0.24,b2>0.13,b4>0.15;其中,在海拔3 000～4 000m区域NDSI阈值大于0.25,海拔4 001～5 000m区域NDSI阈值大于0.45,海拔5 000m以上区域NDSI阈值大于0.5;利用Kappa检验阈值精度,Khat系数均高于90%,说明该研究确立的HJ-1B数据提取积雪的NDSI阈值合理有效.

Water-pipe tobacco epidemic in tobacco naive communities: Experience from Ethiopia

Water-pipe tobacco (WPT) is a public health threat of the 21st century. As a fashion, it swiftly spreads to all corners of the world in no more than two decades. It is a new phenomenon for Ethiopiain general and for Amhara National Regional Statein particular. The major objective of this study was to gain in-depth baseline information about water-pipe tobacco smoking practice in Bahir Dar City, 2012. An explorative study was conducted at Bahir Dar City—capital of Amhara National Regional State. It is home for one of the largest universities in the country with more than 40,000 students. Of the total 50 WPT lounges, six were identified based on their customer variety, and loaded by the help of police officers who had ample experience in fighting the expansion of WPT smoking in the city. A total of 115 people participated in this study. In-depth interviews and focus group discussions (FGD) were conducted, and the tape recorded data were thematically analyzed. More than 80% of the study participants were below 40 Years, and more than 30% of the total study participants were students. The profession of the remaining participants ranges from daily laborers to university instructors. Females accounted for 37.39%. The following factors were found to be pertinent for rapid increment of water-pipe tobacco smoking: geographic and economic accessibility, peer pressure, deceiving characteristics of WPT-non-irritant and aromatic, lack of knowledge, and absence of effective policy. The most outstanding findings of this study were the following: almost all of the study participants were tobacco naive and really unaware of the contents WPT;but about 94% of them had been khat chewers before they started with WPT smoking. In this region, khat had until recently been used by the Muslims only. WPT smoking is an even more recent phenomenon. “Khat stimulates, and WPT calms down,” said study participants. That means by using the later as an antidote for the former, people start ruining their health with substances containing chemicals proven to be notorious to human health. This combination of deadly addictions seems to be peculiar to Ethiopia and appears to be a serious public health threat to tobacco naive communities in the region. Therefore, their rapid progression needs to be met with appropriate interventions urgently. It also warrants further investigations.

苗族《开亲歌》中的传统婚俗

苗族《开亲歌》作为一种"活态"的口传艺术,一定程度上反映了苗族传统婚姻的发展脉络,蕴藏着苗家人的婚姻价值与生命意识,且作为苗族传统婚俗与婚姻规制的传承诉求,鲜活地存在于人们的日常生活中,成为苗族传承历史的活的载体。论文结合田野考察实况,分析《开亲歌》中的传统婚俗,从礼物、媒人、"舅喊钱"等方面探究其作为苗族传统"活态"载体的重要作用及存在意义。

恰特草成分及毒理作用研究进展

恰特草是新精神活性物质中的一种,本文在评述其化学成分及检验技术基础上,对其药理作用研究进展进行了综述,以期对物证鉴定、案件侦破与诉讼提供科学理论依据。

FTIR结合化学计量学方法鉴别恰特草及其形近植物

目的 利用FTIR结合化学计量学方法区分恰特草与其形近植物白茶、鱼腥草,为走私犯罪和公安禁毒工作中鉴别恰特草及其伪装品、易混淆品提供依据。方法 利用FTIR采集植物样品的红外光谱数据,结合化学计量学方法分析数据。选用SG卷积平滑、去基线、归一化三种数据处理方式对原始数据进行预处理,处理后的数据通过PCA进行分类和数据降维,最后选取KNN、RF、SVM三种模式识别方法构建数学模型进行分类和预测。结果 建模预测结果利用混淆矩阵表达,其中RF模型准确度96.51%;SVM模型准确度98.84%;KNN模型准确度93.02%。结论 本实验利用FTIR建立一种快速鉴别恰特草的数学模型,其中SVM模型正确识别率最高,各参数良好,是区别干燥恰特草及其形近植物品的最优模型。