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Measurement of some Benzylisoquinoline Alkaloids in Different Organs of Persian Poppy during Ontogenetical Stages
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Mahdi Rezaei Mohammad Reza Naghavi Abdol Hadi Hosseinzadeh Alireza Abbasi 《化学与生物多样性》2016,13(5):539-543
Papaver bracteatum, a perennial species, has been known as a rich source of thebaine and a potential alternative to Papaver somniferum for the production of codeine and some semisynthetic antagonist drugs. In this study, ion mobility spectrum (IMS) of the root, leaf, bottom part of stem, upper part of stem, capsule wall, petal, and capsule content during developmental stages of P. bracteatum including annual rosette, perennial rosette, bud initiation, pendulous bud, preflowering, and lancing were investigated. The IMS revealed thebaine, papaverine, and noscapine as the major components of the extracted alkaloids. Based on the results of the study it appears that, at least in part, there is a competition among the biosynthesis pathways of papaverine, noscapine, and morphinan alkaloids from a common source . Root and capsule wall were the most potent organs for extraction of thebaine, while lancing stage was the best developmental stage for thebaine exploitation. However, it seems that total biomass of root and capsule wall plays a key role in the final selection of favorite organ. Although papaverine and noscapine in the stem at preflowering stage had the most quantity, significant amounts were found in the capsule wall. In general, total alkaloid content of leaf was lower than the other plant parts. 相似文献
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Dustin T. Duncan Farzana Kapadia Seann D. Regan William C. Goedel Michael D. Levy Staci C. Barton Samuel R. Friedman Perry N. Halkitis 《PloS one》2016,11(2)
Background
No global positioning system (GPS) technology study has been conducted among a sample of young gay, bisexual, and other men who have sex with men (YMSM). As such, the purpose of this study was to evaluate the feasibility and acceptability of using GPS methods to understand the spatial context of substance use and sexual risk behaviors among a sample of YMSM in New York City, a high-risk population.Methods
Data came from a subsample of the ongoing P18 Cohort Study (n = 75). GPS feasibility and acceptability among participants was measured with: 1) a pre- and post-survey and 2) adherence to the GPS protocol which included returning the GPS device, self-report of charging and carrying the GPS device as well as objective data analyzed from the GPS devices. Analyses of the feasibility surveys were treated as repeated measures as each participant had a pre- and post-feasibility survey. When comparing the similar GPS survey items asked at baseline and at follow-up, we present percentages and associated p-values based on chi-square statistics.Results
Participants reported high ratings of pre-GPS acceptability, ease of use, and low levels of wear-related concerns in addition to few concerns related to safety, loss, or appearance, which were maintained after baseline GPS feasibility data collection. The GPS return rate was 100%. Most participants charged and carried the GPS device on most days. Of the total of 75 participants with GPS data, 75 (100%) have at least one hour of GPS data for one day and 63 (84%) had at least one hour on all 7 days.Conclusions
Results from this pilot study demonstrate that utilizing GPS methods among YMSM is feasible and acceptable. GPS devices may be used in spatial epidemiology research in YMSM populations to understand place-based determinants of health such as substance use and sexual risk behaviors. 相似文献35.
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Shima Tavakol Reza Saber Elham Hoveizi Hadi Aligholi Jafar Ai Seyed Mahdi Rezayat 《Molecular neurobiology》2016,53(5):3298-3308
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Mahdi Arzanlou Saeid Ghasemi Maryam Baradaran Bagheri 《Journal of Phytopathology》2016,164(10):833-839
Trunk diseases are potential threats for almond productivity and longevity worldwide, including Iran. In a recent survey on fungal species associated with trunk diseases of almonds in north‐western Iran, Collophora isolates (tentatively identified as Collophora hispanica) were recovered with high frequency from wood samples with internal necrosis and brown to black vascular streaking of almond trees showing symptoms of decline. However, the pathogenic potential of Collophora isolates on almond trees in Iran remains unproven. In this study, the identity of the isolates was further confirmed as C. hispanica based on a combination of morphological data and sequence data of ITS‐rDNA region, and pathogenicity of C. hispanica isolates on almond was evaluated using excised shoot method and in greenhouse experiments. Collophora hispanica isolates induced lesions statistically different from the control, in both excised shoot method and greenhouse assays. Significant differences were observed among the isolates in the length of the lesion induced on wood. Collophora hispanica should be considered as the main trunk pathogens of almond trees in north‐western region of Iran. The distribution and host range of this new pathogen on almond remains to be studied. 相似文献
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Uneven Distribution of Mating‐Type Alleles Among Togninia minima Isolates,One of the Causal Agents of Leaf Stripe Disease on Grapevines in Northwest Iran
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Abolfazl Narmani Mahdi Arzanlou Asadollah Babai‐Ahari 《Journal of Phytopathology》2016,164(7-8):441-447
Togninia minima is the main fungal species associated with grapevine leaf stripe disease worldwide. This species is mainly known from its asexual state in nature; nevertheless, a biallelic heterothallic mating strategy has been confirmed for this species based on in vitro crossing studies. There are no data available on the incidence of an active sexual cycle within the populations of this species in many grapevine‐producing countries as well as Iran. The possibility of a clandestine sexual cycle within the Iranian isolates of T. minima was evaluated by analysing the distribution and frequency of the mating‐type alleles on a microspatial and a macrogeographical scales. Towards this aim, a total of 90 T. minima isolates were recovered from grapevines with esca disease from the vineyards in north and north‐western Iran. A multiplex PCR method previously designed by authors was applied for simultaneous identification and determination of the mating‐type alleles in T. minima populations. The results on the screening of mating‐type alleles using multiplex PCR method revealed the mating‐type identity of 77 isolates as Mat1‐2 and 23 isolates as Mat1‐1. Our results showed that both Mat1‐1 and Mat1‐2 isolates are present in a single vineyard and even on single vines. The distribution of mating‐type alleles in the sampled area skewed from the 1 : 1 ratio (77 : 23); however, co‐occurrence of both mating types in a single vineyard and even on single vines is suggestive for the presence of an active sexual cycle for T. minima in north‐western Iran. 相似文献
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