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1.
Hallucinogenic fungi synthesize two controlled substances, psilocin and psilocybin. Possession of the fungal species that contain these compounds is a criminal offence in North America. Some related species that are morphologically similar, do not contain the controlled substances. Therefore, unambiguous identification of fungi to the species level is critical in determining if a mushroom is illegal. We investigate a phylogenetic approach for the identification of species that contain the psychoactive compounds. We analyzed 35 North American specimens representing seven different genera of hallucinogenic and non-hallucinogenic mushrooms. We amplified and sequenced the internal transcribed spacer region of the rDNA (ITS-1) and a 5' portion of the nuclear large ribosomal subunit of rRNA (nLSU rRNA or 28S). ITS-1 locus sequence data was highly variable and produced a phylogenetic resolution that was not consistent with morphological identifications. In contrast, the nLSU rRNA data clustered isolates from the same species and separated hallucinogen containing and non-hallucinogen containing isolates into distinct clades. With this information, we propose an approach that combines the specificity of PCR detection and the resolving power of phylogenetic analysis to efficiently and unambiguously identify hallucinogenic fungal specimens for legal purposes.  相似文献   

2.
"Magic mushroom (MM)" is the name most commonly given to psychoactive fungi containing the hallucinogenic components: psilocin (1) and psilocybin (2). We investigated the rRNA gene (internal transcribed spacer (ITS) and large subunit (LSU)) of two Panaeolus species and four Psilocybe species fungi (of these, two are non-psilocybin species). On the basis of sequence alignment, we improved the identification system developed in our previous study. In this paper, we describe the new system capable of distinguishing MMs from non-psilocybin Psilocybe species, its application data and the phylogeny of MM species.  相似文献   

3.
In nature, there are >200 species of fungi with hallucinogenic properties. These fungi are classified as Psilocybe, Gymnopilus, and Panaeolus which contain active principles with hallucinogenic properties such as ibotenic acid, psilocybin, psilocin, or baeocystin. In Chile, fungi seizures are mainly of mature specimens or spores. However, clandestine laboratories have been found that process fungus samples at the mycelium stage. In this transient stage of growth (mycelium), traditional taxonomic identification is not feasible, making it necessary to develop a new method of study.Currently, DNA analysis is the only reliable method that can be used as an identification tool for the purposes of supporting evidence, due to the high variability of DNA between species. One way to identify the species of a distinctive DNA fragment is to study PCR products analyzed by real time PCR and sequencing. One of the most popular sequencing methods of forensic interest at the generic and intra-generic levels in plants is internal transcribed spacer (ITS). With real time PCR it is possible to distinguish PCR products by differential analysis of their melting temperature (Tm) curves.This paper describes morphological, chemical, and genetic analysis of mycelia of psychedelic fungi collected from a clandestine laboratory. The fungus species were identified using scanning electron microscopy (SEM), mass spectrometry, HRM analysis, and ITS sequencing. The sporological studies showed a generally smooth surface and oval shape, with maximum length 10.1?μm and width 6.4?μm. The alkaloid Psilocyn was identified by mass spectrometry, while HRM analysis and ITS sequencing identified the species as Psilocybe cubensis. A genetic match was confirmed between the HRM curves obtained from the mycelia (evidence) and biological tissue extracted from the fruiting bodies. Mycelia recovered from the evidence and fruiting bodies (control) were genetically indistinguishable.  相似文献   

4.
致幻剂是一类低剂量就使人意识、知觉和视觉异常,引起幻觉和情绪障碍的精神活性物质。赛洛新和赛洛西宾是一类具有致幻作用的色胺类化合物,存在于裸盖伞属和斑褶菇属的致幻蘑菇中。当前滥用及娱乐性使用含此类物质的致幻蘑菇的现象日趋严重,由此引起的危害公共安全案(事)件不断增多。因此,对于致幻蘑菇滥用的鉴定是当前司法鉴定领域的重要需求和国际热点研究问题之一。通过对赛洛新和赛洛西宾的药理毒理、体内过程、检材处理方法和分析检测方法进行了综述,以期为司法鉴定实践提供参考。  相似文献   

5.
目的通过检测嗜尸性蝇类28S r RNA基因中715 bp序列,鉴定常见嗜尸性蝇类种属,解决其形态学鉴定难题,为死亡时间推断提供技术支持。方法收集洛阳地区常见嗜尸性蝇类标本29只,经形态学鉴定后,用Chelex-100法提取腿部DNA,并对28S r RNA基因片段进行扩增和测序,与Gen Bank和EMBL数据库中的28条相应蝇种序列进行比对,用MEGA7.0软件进行序列整理,通过BLAST搜索进行序列比对,并分析所得序列碱基组成,建立种内及种间进化分歧率,构建系统发育树。结果形态学鉴定29只嗜尸性蝇类归属于3科5属6种。获得28S r RNA基因中715 bp的序列,在线BLAST比对结果显示相似度100%。系统发育树显示5种蝇类可以较好聚类。不同蝇种种间差异0.007~0.045,种内差异0~0.001,种间差异和种内差异没有交叉。结论 28S r RNA靶基因序列片段对嗜尸性蝇类有良好的鉴别能力,可以作为新的嗜尸性蝇类种属鉴定遗传标记。  相似文献   

6.
On May 25, 2006, DEA published a Notice of Proposed Rulemaking which proposed the addition of a specific definition for the term "positional isomer" to allow for the systematic determination of which isomers of schedule I substances would be considered to be "positional," and therefore, subject to schedule I control. This rulemaking finalizes that definition. The Controlled Substances Act (CSA) and its implementing regulations specify which hallucinogenic substances are considered schedule I controlled substances. The CSA states that all salts, isomers, and salts of isomers of these substances are also schedule I controlled substances. In non-technical terms, an isomer of a substance is a different compound, but a compound which has the same number and kind of atoms. The terms "optical isomer" and "geometric isomer" are specific scientific terms and it is easy to determine whether one substance is an optical or geometric isomer of another. The term "positional isomer," however, is subject to scientific interpretation. The addition of a definition for the term "positional isomer" will assist legitimate research[ers] and industry in determining the control status of materials that are "positional isomers" of schedule I hallucinogens. While the DEA will remain the authority for ultimately determining the control status of a given material, providing a specific definition for "positional isomer" will ensure consistent criteria are utilized in making these determinations. This rule does not change existing laws, regulations, policies, processes, and procedures regarding the determination of control status for schedule I hallucinogenic substances. This rule merely makes available to the public the longstanding definition of "positional isomer" which DEA has used when making these scheduling determinations. This rule is relevant only to specialized forensic or research chemists. Most of these individuals are existing DEA registrants who are authorized by the DEA to handle schedule I hallucinogenic substances.  相似文献   

7.
Abuse of hallucinogens produced by the fungal genera Psilocybe and Panaeolus are a growing problem. Five species from each of the two genera were examined in this preliminary research and a method that will unambiguously identify fungal samples as being of one of these two genera has been developed. The method uses genus specific DNA sequences within the Internal Transcribed Spacer of the ribosomal gene complex. Amplification of a common DNA product and a genus specific product results in two identifiable products, which facilitates the unambiguous identification of material from these two fungi to generic level.  相似文献   

8.
Abstract: Correct species identification is critical when dipteran larvae are used for inference of the postmortem interval. To facilitate DNA‐based identification of forensically important flies of the genus Lucilia in the continental United States, we develop a vouchered reference collection and DNA sequence database. A total of 122 specimens were collected for nine of the 10 species of Lucilia reported to occur in the continental United States. Using the polymerase chain reaction and DNA sequencing, data were obtained for an 1100‐bp region of the mitochondrial gene encoding cytochrome oxidase I (COI). We consider a species suitable for DNA‐based identification if it is exclusively monophyletic in >95% of bootstrap pseudoreplicate phylogenetic analyses. Seven of the nine species meet that criterion. Two species (Lucilia coeruleiviridis and Lucilia mexicana) share COI sequence and cannot be distinguished using our reference database. We conclude that DNA‐based identification is likely to be successful for the other seven species.  相似文献   

9.
The exhibits obtained in wildlife offence cases quite often present a challenging situation for the forensic expert. The selection of proper approach for analysis is vital for a successful analysis. A generalised forensic analysis approach should proceed from the use of non-destructive techniques (morphological and microscopic examination) to partially destructive and finally destructive techniques (DNA analysis). The findings of non-destructive techniques may sometime be inconclusive but they definitely help in steering further forensic analysis in a proper direction. We describe a recent case where a very small dried skin piece (< 0.05 mg) with just one small trimmed guard hair (0.4 cm) on it was received for species identification. The single guard hair was examined microscopically to get an indication of the type of species. We also describe the extraction procedure with a lower amount of sample, using an automated extraction method (Qiagen Biorobot EZ1®) and PCR amplification of three mitochondrial genes (16s rRNA, 12s rRNA and cytochrome b) for species identification. Microscopic examination of the single hair indicated a viverrid species but the initial DNA analysis with 16s rRNA (through NCBI BLAST) showed the highest homology (93%) with a hyaenid species (Hyaena hyaena). However, further DNA analysis based on 12s rRNA and cytochrome b gene proved that the species was indeed a viverrid i.e. Viverricula indica (small Indian civet). The highest homology shown with a Hyaenid species by the 16s rRNA sequence from the case sample was due to lack of a 16s rRNA sequence for Viverricula indica in the NCBI data base. The case highlights the importance of morphological and microscopic examinations in wildlife offence cases. With respect to DNA extraction technology we found that automatic extraction method of Biorobot EZ1® (Qiagen) is quite useful with less amount of sample (much below recommended amount).  相似文献   

10.
'Magic mushrooms' is the name most commonly given to psychoactive fungi containing the hallucinogenic components psilocybin and psilocin. Material confiscated by local authorities was examined using morphologic, microscopic, microchemical, and toxicological methods. Psilocybe cubensis was the most popular mushroom in the sample collective, followed by Psilocybe semilanceata, Panaeolus cyanescens and Psilocybe tampanensis. The alkaloid content was determined with <0.003-1.15% of psilocybin and 0.01-0.90% psilocin. Panaeolus cyanescens was the mushroom with highest levels of psilocybin and psilocin.  相似文献   

11.
Recent studies suggest that sequence analysis technique displays a tempting foreground in identifying unknown specimens of necrophagous flies. In this study, we analyzed 63 complete ITS2 sequences concerning 29 fly species to evaluate the identification potential of the ITS2 region, among of which 41 sequence entries were obtained by sequencing and 22 sequence entries were available on the line. Additionally, phenetic method was recommended to substitute for phylogenetic method because it is very difficult to align the ITS2 sequences. The neighbor-joining tree generated by clustalx1.81 allowed us to differentiate each species. Meanwhile the tree topology also suggested that the ITS2 region showed no resolution for the distinction of geographical populations of some species. The overlapping between intra- and interspecific variation revealed by sequence analyses did not affect species identification. High sequence homology between some congeneric species required further sequencing for forensic practice.  相似文献   

12.
A proliferation of molecular studies of the forensically significant Calliphoridae in the last decade has seen molecule-based identification of immature and damaged specimens become a routine complement to traditional morphological identification as a preliminary to the accurate estimation of post-mortem intervals (PMI), which depends on the use of species-specific developmental data. Published molecular studies have tended to focus on generating data for geographically localised communities of species of importance, which has limited the consideration of intraspecific variation in species of global distribution. This study used phylogenetic analysis to assess the species status of 27 forensically important calliphorid species based on 1167 base pairs of the COI gene of 119 specimens from 22 countries, and confirmed the utility of the COI gene in identifying most species. The species Lucilia cuprina, Chrysomya megacephala, Ch. saffranea, Ch. albifrontalis and Calliphora stygia were unable to be monophyletically resolved based on these data. Identification of phylogenetically young species will require a faster-evolving molecular marker, but most species could be unambiguously characterised by sampling relatively few conspecific individuals if they were from distant localities. Intraspecific geographical variation was observed within Ch. rufifacies and L. cuprina, and is discussed with reference to unrecognised species.  相似文献   

13.
目的以rDNA-ITS序列片段为植物DNA条形码,对涉及一例交通命案的植物检材进行种属鉴定,判断三轮车左侧车体上提取的树皮样物质与农用车所运的树木是否为同一树种。方法采用改良CTAB法提取植物DNA,先将DNA纯化,再进行rDNA-ITS的PCR扩增,然后对PCR产物切胶、回收,克隆、测序,对测序结果进行BLAST分析,并构建系统发育树。结果三轮车上粘附的树皮来源于柑橘(Citrus sunki),农用车所运的树木为界山三角槭(Acer buergerianum),两者非同一种属。结论用rDNA-ITS序列片段用作植物DNA条形码对植物种属进行鉴定,可获得可靠的鉴定意见。  相似文献   

14.
Invasive fungal infections are a leading cause of morbidity and mortality in immunocompromised patients, especially in cases requiring a prolonged stay in the intensive care unit. A total of 99 yeast strains were isolated from 42 postmortem cases. In this study, virulence factors and antifungal susceptibility of these species were evaluated. The isolates were identified as Candida albicans (54), C. tropicalis (15), C. glabrata (12), C. parapsilosis (6), C. lipolytica (3), C. utilis (3), C. krusei (2), C. kefyr (1), and Cryptococcus neoformans (3). The most commonly isolated species was C. albicans, and no resistant species were determined. Despite the equal number of specimens, no secretion of significant virulence factors was associated with the postmortem specimen in the Candida species. Postmortem fungal investigations in forensic autopsies are useful in explaining cause of death in such cases, also may lead to protocols for the treatment of fungal infections and contribute to fungal pathogenesis and epidemiological data.  相似文献   

15.
Cai JF  Ying BW  Tao T 《法医学杂志》2005,21(1):68-72
嗜尸性蝇类种属鉴定是利用昆虫进行检案的重要一步,常常对案件的侦破起到关键作用。传统上,仅依据其形态学特征来判断嗜尸性蝇类的种属。由于其形态结构复杂和种间形态差异微小等特点,尤其在其幼期很难鉴别其种属。利用线粒体DNA(mtDNA)上细胞色素氧化酶辅酶Ⅰ和Ⅱ(COⅠ和COⅡ)的序列对嗜尸性蝇类进行种属鉴定,是近几年来发展起来的新技术,该检测方法能有效地将嗜尸性蝇类鉴定到属种的水平,目前国内尚无这方面的报道,本文对国外这方面工作的进展作一综述。  相似文献   

16.
Salvia divinorum Epling & Jativa is an hallucinogenic mint traditionally used for curing and divination by the Mazatec Indians of Oaxaca, Mexico. Young people from Mexican cities were reported to smoke dried leaves of S. divinorum as a marijuana substitute. Recently, two S. divinorum specimens were seized in a large-scale illicit in-door and out-door hemp plantation. Salvinorin A also called divinorin A, a trans-neoclerodane diterpene, was identified in several organic solvent extracts by gas chromatography-mass spectrometry. The botanical identity of the plant was confirmed by comparing it to an authentic herbarium specimen. More plants were then discovered in Swiss horticulturists greenhouses. All these data taken together suggest that many attempts exist in Switzerland to use S. divinorum as a recreational drug. This phenomenon may be enhanced because neither the magic mint, nor its active compound are banned substances listed in the Swiss narcotic law.  相似文献   

17.
Pulmonary hemosiderosis has been attributed to airborne fungi in water-damaged homes in studies of a cluster of cases in infants and children in Cleveland, Ohio, in 1997. We have searched for such emerging infectious agents in the Coastal Plain of North Carolina, which is subject to intermittent flooding. Pulmonary tissue from 206 infants and young children whose deaths had been investigated from October 1978 to September 1996 was retained at East Carolina University School of Medicine. Ages ranged from premature newborns to 49-months. One hundred and ten deaths were attributed to sudden infant death syndrome (SIDS). New sections were cut and analyzed using hematoxylin and eosin, Prussian blue for iron, and Gomori methenamine silver for fungal organisms. Twenty-three infants and children had iron-containing macrophages. Sixteen of these had underlying illnesses, but 4 were originally diagnosed as SIDS. Only one of these had sufficient hemosiderosis to be considered as having pulmonary hemosiderosis and no fungi were present. One case without iron had fungi and was not originally diagnosed as SIDS. The single case of pulmonary hemosiderosis found in this rural area is not similar to the cluster in Cleveland. The study identifies no fungal organisms as emerging infectious diseases in this area.  相似文献   

18.
Abstract: We illustrate an interdisciplinary approach to identify a victim in a case with complex taphonomic and procedural issues. Burning, fragmentation, species commingling, and examination by multiple experts required anthropological preparation and analysis combined with radiographic adaptations to image and match trabecular patterns in unusually small, burned specimens. A missing person was last seen in the company of a reclusive female on a remote rural property. A warranted search found several burn sites containing human and animal bones. Fragment preparation, analysis, and development of a biological profile by anthropologists enabled examination by the odontologist, molecular biologist, and radiologist, and justified use of antemortem radiographs from one potential victim. Visual and radiological comparison resulted in a positive (later confirmed) identification of the victim by radiological matches of three carpal phalanges. Although some dimensional changes are expected with burning, morphological details were preserved, aided by selection of relatively intact, small bones for comparison.  相似文献   

19.
The biodiversity of India includes three crocodile species, Crocodylus palustris, Crocodylus porosus, and Gavialis gangeticus, whose status is threatened due to bushmeat crisis and illegal hunting. The crocodilian conservation management requires novel techniques to help forensic analysts to reveal species identity. DNA barcoding is a species identification technique, where a partial cytochrome c oxidase subunit 1 gene is used as a marker for species identification. Herein, the DNA barcoding technique is evaluated for three Indian crocodiles by analyzing an approximately 750‐bp barcode region. The alignment result shows interspecific variations between sequences for discrimination of the three Indian crocodiles leading to species identification. The phylogenetic analyses also substantiate the established crocodilian relationships, which add further advantage to use this DNA barcoding approach for Indian crocodiles. This study provides preliminary evidences for the use of DNA barcoding technique in the identification of Indian crocodile species.  相似文献   

20.
目的通过对几种涉案犀牛角制品的12s rRNA条形码序列比对分析,探析12s rRNA在犀牛角制品种属鉴定中的应用可行性。方法以3个案件中的涉案犀牛角制品为材料,采用改良的基因组DNA提取方法,PCR扩增DNA条形码片段12s rRNA。结果通过序列比对与分析,表明12s rRNA可将涉案犀牛角制品鉴定到种的水平。结论 DNA条形码12s rRNA可以作为一个新手段对形态上无法鉴别的犀牛角制品进行准确的种属鉴定,为案件的定性与量刑提供可靠的依据。  相似文献   

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