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RECENT interesting findings

Tonygreen

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Im still going with my theory they all have intersex ability.

I have not seen a plant that won't herm, again my sample size is much smaller than many.
Some have said I have females that wont produce pollen when reversed, but they still produce balls.
Many are more stable than others but if I fuck with em enough they intersex.

Has anyone seen a "pure" female that wont show intersex?
 

Sam_Skunkman

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I have seen them, both that will not show intersex and plants and /or that will make male flowers but no viable pollen. I do not consider the later pure female. As they may yield progeny that makes fertile intersex flowers.
-SamS
 

Illuminate

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I think under high selective pressure with large plant count, it's easier to find true females. Over the years I have deliberately messed with the lights and nutrition schedule during my search for mums, and found at least 10 different plants that did not produce pollen or sacs under those conditions. Probably about 5% or less of all the plants I've ever stressed were those girls, Exodus cheese aka skunk#1 was one.
 

Sam_Skunkman

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One more, and this one is really good:

http://onlinelibrary.wiley.com/doi/10.1111/nph.13562/full



Gene duplication and divergence affecting drug content in Cannabis sativa
New Phytologist 17 July 2015
George D. Weiblen, Jonathan P. Wenger, Kathleen J. Craft, Mahmoud A. ElSohly,
Zlatko Mehmedic, Erin L. Treiber, M. David Marks

Summary

Cannabis sativa is an economically important source of durable fibers, nutritious seeds, and psychoactive drugs but few economic plants are so poorly understood genetically.

Marijuana and hemp were crossed to evaluate competing models of cannabinoid inheritance and to explain the predominance of tetrahydrocannabinolic acid (THCA) in marijuana compared with cannabidiolic acid (CBDA) in hemp. Individuals in the resulting F2 population were assessed for differential expression of cannabinoid synthase genes and were used in linkage mapping. Genetic markers associated with divergent cannabinoid phenotypes were identified.

Although phenotypic segregation and a major quantitative trait locus (QTL) for the THCA/CBDA ratio were consistent with a simple model of codominant alleles at a single locus, the diversity of THCA and CBDA synthase sequences observed in the mapping population, the position of enzyme coding loci on the map, and patterns of expression suggest multiple linked loci. Phylogenetic analysis further suggests a history of duplication and divergence affecting drug content.

Marijuana is distinguished from hemp by a nonfunctional CBDA synthase that appears to have been positively selected to enhance psychoactivity. An unlinked QTL for cannabinoid quantity may also have played a role in the recent escalation of drug potency.
 
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Sam_Skunkman

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A new review and an older review but great.
Old:
http://www.researchgate.net/publica...overview_of_chemical_research_on_cannabinoids

A historical overview of chemical research on cannabinoids
Chemistry and Physics of Lipids
108 (2000) 1–13
Raphael Mechoulam , Lumı´r Hanusˇ
Department of Medicinal Chemistry and Natural Products, Hebrew Uni6ersity of Jerusalem, Medical Faculty, Ein Kerem Campus,
91120 Jerusalem, Israel

Abstract
The chemical research on the plant cannabinoids and their derivatives over two centuries is concisely reviewed. The tortuous path leading to the discovery of the endogenous cannabinoids is described. Future directions, which will probably be followed are delineated.

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NEW:

http://www.researchgate.net/publica...noid_chemistry_to_endocannabinoids_and_beyond

Early phytocannabinoid chemistry to endocannabinoids and beyond
Nature Reviews / Neuroscience Vol 15 Nov 1014 Pg 757-764 Perspectives
Raphael Mechoulam, Lumír O. Hanuš, Roger Pertwee and
Allyn C. Howlett
Abstract
Isolation and structure elucidation of most of the major cannabinoid constituents — including Δ9-tetrahydrocannabinol (Δ9-THC), which is the principal psychoactive molecule in Cannabis sativa — was achieved in the 1960s and 1970s. It was followed by the identification of two cannabinoid receptors in the 1980s and the early 1990s and by the identification of the endocannabinoids shortly thereafter. There have since been considerable advances in our understanding of the endocannabinoid system and its function in the brain, which reveal potential therapeutic targets for a wide range of brain disorders.
 
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Sativied

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One more:

http://onlinelibrary.wiley.com/doi/10.1111/nph.13562/full

Gene duplication and divergence affecting drug content in Cannabis sativa

That should be mandatory reading for any cannabis breeder, especially for those underestimating or even denying the importance of mendel's work. Read at least the Quality vs Quantity and Cannabinoid synthase evolution sections.

The former shows nicely how important it is to distinguish between qualitative traits and quantitative traits, which directly affects a breeding program and required plant count. Only need a few plants and generations to breed a trait into another variety, getting it in the highest amounts and uniform is much harder and requires more plants and more generations.
 

Sam_Skunkman

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Not new, not Cannabis specific, but maybe interesting?

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3474957/

Effect of Soil Nutrient on Production and Diversity of Volatile Terpenoids from Plants
E Ormeño* and C Fernandez

Curr Bioact Compd. 2012 Jan; 8(1): 71–79.

Abstract
Terpenoid production (emission and storage) within foliage plays direct and indirect defensive and protective functions for the plant, mediates complex trophic relationships and controls the oxidation capacity of the atmosphere. Both biotic and abiotic conditions alter terpenoid production, with herbivory, light and temperature effects being reasonably well understood. In this manuscript, the state of the science about nutrient effect on terpenoid production is reviewed. The focus is on isoprene emissions and mono- and sesquiterpenoid emissions and concentrations according to fertilizing treatments and their potential interaction with other environmental factors. Ecological, physiological, biochemical and biophysical hypothesis formulated over research investigations are exposed and several points are highlighted as future research perspectives which could help to elucidate the apparent contrasting results.
 

Sam_Skunkman

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http://www.ncbi.nlm.nih.gov/pubmed/26577065


J Psychopharmacol. 2015 Nov 17. pii: 0269881115615104. [Epub ahead of print]
The effect of five day dosing with THCV on THC-induced cognitive, psychological and physiological effects in healthy male human volunteers: A placebo-controlled, double-blind, crossover pilot trial.
Englund A1, Atakan Z2, Kralj A2, Tunstall N2, Murray R2, Morrison P2.

Abstract
RATIONALE:
Cannabis is mostly grown under illegal and unregulated circumstances, which seems to favour a product increasingly high in its main cannabinoid ∆-9-tetrahydrocannabinol (THC). ∆-9-tetrahydrocannabivarin (THCV) is a relatively untested cannabinoid which is said to be a cannabinoid receptor neutral antagonist, and may inhibit the effects of THC.
OBJECTIVES:
To explore the safety and tolerability of repeated THCV administration and its effects on symptoms normally induced by THC in a sample of healthy volunteers.
METHODS:
Ten male cannabis users (<25 use occasions) were recruited for this within-subjects, placebo-controlled, double-blind, cross-over pilot study. 10mg oral pure THCV or placebo were administered daily for five days, followed by 1mg intravenous THC on the fifth day.
RESULTS:
THCV was well tolerated and subjectively indistinguishable from placebo. THC did not significantly increase psychotic symptoms, paranoia or impair short-term memory, while still producing significant intoxicating effects. Delayed verbal recall was impaired by THC and only occurred under placebo condition (Z=-2.201, p=0.028), suggesting a protective effect of THCV. THCV also inhibited THC-induced increased heart rate (Z=-2.193, p=0.028). Nine out of ten participants reported THC under THCV condition (compared to placebo) to be subjectively weaker or less intense (χ2=6.4, p=0.011). THCV in combination with THC significantly increased memory intrusions (Z=-2.155, p=0.031).
CONCLUSION:
In this first study of THC and THCV, THCV inhibited some of the well-known effects of THC, while potentiating others. These findings need to be interpreted with caution due to a small sample size and lack of THC-induced psychotomimetic and memory-impairing effect, probably owing to the choice of dose.



FYI, I did THCV/THC trials 15 years ago, unpublished, but we found much the same, THCV is not for recreational users unless they like their THC tuned down. THCV delays THC onset, reduces peak experiences, and maybe lengthens the reduced effects.
-SamS
 
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FYI, I did THCV/THC trials 15 years ago, unpublished, but we found much the same, THCV is not for recreational users unless they like their THC tuned down. THCV delays THC onset, reduces peak experiences, and maybe lengthens the reduced effects.
-SamS
Been interested in metabolic trials as regards these two. Or rather if THCV is a green light to amplify metabolites. The drug affect might still be there in its typical role, but anabolism is over-compensating pushing enzymatic process to the fore. Current studies make it sound like one is still just as high, with greater metabolic threshold. One is not hypothetically "less high", but working harder. Question being which wears off quicker the homologue or THC? Maybe compartmentalizing studies to anabolic vs. psychoactive is a means to circumvent scientific preoccupation with attenuates.
 
Sam Skunkman if there is no more road kill skunk could you please tell me where you grew the original. I miss the old funky skunky and now that it is possible to grow my own legally I would like to grow some of that.
 

Sam_Skunkman

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https://drive.google.com/file/d/0BwcyJZbpGU4sNzFLQzBZRHh2R0k/view

Multidimensional analysis of Cannabis volatile constituents: Identification of 5,5-dimethyl-1-vinylbicyclo[2.1.1]hexane as a volatile marker of Hashish, the resin of Cannabis sativa.

Journal of Chromatography A Nov 2014 DOI: 10.1016/j.chroma.2014.10.045

Abstract
Female flowers of Cannabis sativa in wild-growing populations and in hemp plantations are almost always well supplied with pollen. The style-stigma portion of the pistils of such plants was found to average only about 3 mm in length and to invariably be two-branched. By contrast, “buds” (congested female inflorescences), the standard form of marijuana now produced in the illicit and medicinal marijuana sectors, are protected against pollen. This report documents that in the absence of pollen, the style-stigma parts of virgin pistils expand notably, average over 8 mm in length, and tend to develop more than two branches and to increase in girth. From an evolutionary viewpoint, this expansion of pollen-receptive tissue is an apparent adaptation for increasing the probability of fertilizing the females when males are extremely scarce. From a practical viewpoint, the expanded presence of stigma tissues may be both advantageous and disadvantageous. The high-THC secretory gland heads of Cannabis tend to fall away from marijuana buds, significantly decreasing pharmacological potency, but many gland heads become stuck to the receptive papillae of the stigmas, reducing the loss. Although stigmas constitute a small proportion of marijuana, their distinctive chemistry could have health effects.
 
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Sam_Skunkman

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http://onlinelibrary.wiley.com/doi/10.1111/1556-4029.12448/abstract

Journal of Forensic Sciences
Volume 59, Issue 4
July 2014
Pages 919–926

A PCR marker Linked to a THCA synthase Polymorphism is a Reliable Tool to Discriminate Potentially THC-Rich Plants of Cannabis sativa L.
Authors
Christina Staginnus Ph.D.,
Siegfried Zörntlein Ph.D.,
Etienne de Meijer Ph.D.
First published: 3 March 2014Full publication history
DOI: 10.1111/1556-4029.12448View/save citation
Cited by: 3 articlesRefresh citation countCiting literature

†The nucleotide sequences reported in this paper are deposited in the NCBI GenBank under accession numbers JQ935235–JQ935244.
Abstract

Neither absolute THC content nor morphology allows the unequivocal discrimination of fiber cultivars and drug strains of Cannabis sativa L. unequivocally. However, the CBD/THC ratio remains constant throughout the plant's life cycle, is independent of environmental factors, and considered to be controlled by a single locus (B) with two codominant alleles (BT and BD). The homozygous BT/BT genotype underlies the THC-predominant phenotype, BD/BD is CBD predominant, and an intermediate phenotype is induced by the heterozygous state (BT/BD). Using PCR-based markers in two segregating populations, we proved that the THCA synthase gene represents the postulated B locus and that specific sequence polymorphisms are absolutely linked either to the THC-predominant or the THC-intermediate chemotype. The absolute linkage provides an excellent reliability of the marker signal in forensic casework. For validation, the species-specific marker system was applied to a large number of casework samples and fiber hemp cultivars.

------------------------
http://www.fsigenetics.com/article/S1872-4973(14)00167-7/abstract

FSI Genetics November 2014Volume 13, Pages 185–186

Nomenclature proposal and SNPSTR haplotypes for 7 new Cannabis sativa L. STR loci

-----------------------

http://www.pubfacts.com/detail/2586...annabinolic-acid-synthase-in-Cannabis-sativa-

Sequence heterogeneity of cannabidiolic- and tetrahydrocannabinolic acid-synthase in Cannabis sativa L. and its relationship with chemical phenotype.

Phytochemistry 2015 Aug 9;116:57-68. Epub 2015 Apr 9.
Chiara Onofri, Etienne P M de Meijer, Giuseppe Mandolino


Sequence variants of THCA- and CBDA-synthases were isolated from different Cannabis sativa L. strains expressing various wild-type and mutant chemical phenotypes (chemotypes). Expressed and complete sequences were obtained from mature inflorescences. Each strain was shown to have a different specificity and/or ability to convert the precursor CBGA into CBDA and/or THCA type products. The comparison of the expressed sequences led to the identification of different mutations, all of them due to SNPs. These SNPs were found to relate to the cannabinoid composition of the inflorescence at maturity and are therefore proposed to have a functional significance. The amount of variation was found to be higher within the CBDAS sequence family than in the THCAS family, suggesting a more recent evolution of THCA-forming enzymes from the CBDAS group. We therefore consider CBDAS as the ancestral type of these synthases.
 
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Sam_Skunkman

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http://www.ncbi.nlm.nih.gov/pubmed/26708108

Neuropsychopharmacology. 2015 Dec 28. doi: 10.1038/npp.2015.367. [Epub ahead of print]
Oral Cannabidiol does not Alter the Subjective, Reinforcing or Cardiovascular Effects of Smoked Cannabis.
Haney M1, Malcolm RJ2, Babalonis S3, Nuzzo PA3, Cooper ZD1, Bedi G1, Gray KM2, McRae-Clark A2, Lofwall MR3, Sparenborg S4, Walsh SL3.

Abstract
Cannabidiol (CBD), a constituent of cannabis with few psychoactive effects, has been reported in some studies to attenuate certain aspects of Δ9-tetrahydrocannabinol (THC) intoxication. However, most studies have tested only one dose of CBD in combination with one dose of oral THC making it difficult to assess the nature of this interaction. Further, the effect of oral CBD on smoked cannabis administration is unknown. The objective of this multi-site, randomized, double-blind, within-subject laboratory study was to assess the influence of CBD (0, 200, 400, 800 mg, p.o.) pretreatment on the reinforcing, subjective, cognitive, and physiological effects of smoked cannabis [0.01 (inactive), 5.30-5.80% THC]. Non-treatment-seeking, healthy cannabis smokers (n=31; 17M,14F) completed 8 outpatient sessions. CBD was administered 90 min prior to cannabis administration. The behavioral and cardiovascular effects of cannabis were measured at baseline and repeatedly throughout the session. A subset of participants (n=8) completed an additional session to measure plasma CBD concentrations after administration of the highest CBD dose (800 mg). Under placebo CBD conditions, active cannabis (1) was self-administered by significantly more participants than placebo cannabis, and (2) produced significant, time-dependent increases in ratings of 'High,' 'Good Effect,' ratings of the cannabis cigarette (eg, strength, liking) and heart rate relative to inactive cannabis. CBD, which alone produced no significant psychoactive or cardiovascular effects, did not significantly alter any of these outcomes. Cannabis self-administration, subjective effects, and cannabis ratings did not vary as a function of CBD dose relative to placebo capsules. These findings suggest that oral CBD does not reduce the reinforcing, physiological or positive subjective effects of smoked cannabis.Neuropsychopharmacology accepted article preview online, 28 December 2015. doi:10.1038/npp.2015.367.
 
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Sam_Skunkman

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http://online.liebertpub.com/doi/pdfplus/10.1089/can.2015.29003.ebr

Cannabis and Cannabinoid Research
Volume 1.1, 2016
DOI: 10.1089/can.2015.29003.ebr

INTERVIEW Open Access
The Cannabis sativa Versus Cannabis indica Debate:
An Interview with Ethan Russo, MD

Daniele Piomelli and Ethan B. Russo
Dr. Ethan Russo, MD, is a board-certified neurologist, psychopharmacology researcher, and Medical Director of PHYTECS, a biotechnology company researching and developing innovative approaches targeting the human endocannabinoid system. Previously, from 2003 to 2014, he served as Senior Medical Advisor and study physician to GW Pharmaceuticals for three Phase III clinical trials of Sativex for alleviation of cancer pain unresponsive to optimized opioid treatment and studies of Epidiolex for intractable epilepsy. He has held faculty appointments in Pharmaceutical Sciences at the University of Montana, in Medicine at the University of Washington, and as visiting Professor, Chinese Academy of Sciences. He is a past President of the International Cannabinoid Research
Society and former Chairman of the International Association for Cannabinoid Medicines. He serves on the Scientific Advisory Board for the American Botanical Council. He is the author of numerous books, book chapters, and articles on Cannabis, ethnobotany, and herbal medicine. His research interests have included correlations of historical uses of Cannabis with modern pharmacological mechanisms, phytopharmaceutical treatment of migraine and chronic pain, and phytocannabinoid/terpenoid/serotonergic/vanilloid interactions.
 
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Sam_Skunkman

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Here is a paper related to an idea I have been considering a while, that terpenes are allosteric modulators of the CB1 receptor like CBD in this paper.
-SamS

http://online.liebertpub.com/doi/pdfplus/10.1089/can.2015.0005

Cannabis and Cannabinoid Research
Volume 1.1, 2016
DOI: 10.1089/can.2015.0005
Allosteric Modulators of the CB1 Cannabinoid Receptor: A Structural Update Review Paula Morales, Pilar Goya, Nadine Jagerovic, and Laura Hernandez-Folgado
Abstract
In 2005, the first evidence of an allosteric binding site at the CB1R was provided by the identification of three indoles of the company Organon that were allosteric enhancers of agonist binding affinity and, functionally, al- losteric inhibitors of agonist activity. Since then, structure–activity relationships of indoles as CB1R modulators have been reported. Targeting the allosteric site on CB1R, new families structurally based on urea and on 3- phenyltropane analogs of cocaine have been discovered as CB1R-negative allosteric modulators (NAMs), respec- tively, by Prosidion and by the Research Triangle Park. Endogenous allosteric ligands of different nature have been identified more recently. Thus, the therapeutic neuroprotection application of lipoxin A4, an arachidonic acid derivative, as an allosteric enhancer of CB1R activity has been confirmed in vivo. It was also the case of the steroid hormone, pregnenolone, whose negative allosteric effects on D9-tetrahydrocannabinol (D9-THC) were reproduced in vivo in a behavioral tetrad model and in food intake and memory impairment assays. Curi- ously, the peroxisome proliferator-activated receptor-c agonist fenofibrate or polypeptides such as pepcan-12 have been shown to act on the endocannabinoid system through CB1R allosteric modulation. The mechanistic bases of the effects of the phytocannabinoid cannabidiol (CBD) are still not fully explained. However, there is evidence that CBD behaves as an NAM of D9-THC- and 2-AG. Allosteric modulation at CB1R offers new oppor- tunities for therapeutic applications. Therefore, further understanding of the chemical features required for allo- steric modulation as well as their orthosteric probe dependence may broaden novel approaches for fine-tuning the signaling pathways of the CB1R.
 
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