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Experimental evaluation of cannabis tolerance has to date lacked an associative approximation, focusing primarily on physiological variables. The present study assessed acute effects, chronic tolerance, and contextual specificity, exploring a potential associative component underlying cannabis tolerance. Sixteen adult Sprague-Dawley rats of both sexes were assigned to two groups, one receiving vaporized administrations of cannabis and the other receiving the vehicle substance, in two different (counterbalanced) contexts. An initial measurement was performed to assess acute effects, followed by four measurements to evaluate the development of chronic tolerance, and a final measurement to test the context specificity of tolerance, comparing the responses to the usual administration context and a novel context. Ten behaviors were analyzed in an open field. Acute effects were observed in seven indicators, corresponding to greater locomotor activity in the group that received the drug compared to the control group. In five of these, the data also showed the development of chronic tolerance to the effects of cannabis on locomotion, which was indicated by a progressive decrease in locomotor activity in the drug group. However, no evidence of context specificity was found in any of the variables in which chronic tolerance was observed. We discuss factors that may be related to the lack of contextual specificity of cannabis tolerance. Together, our findings show that a single administration of cannabis induces acute effects, and its consecutive consumption develops chronic tolerance to these effects, reaching a hypolocomotor state.

ObjectiveThe social conditions are changing in the world, which may contribute to the change in lifestyle, including alcohol consumption and dietary intake; however, changes in metabolic complications in patients with alcoholic fatty liver disease (AFLD) have never been reported. Therefore, here we compare the metabolic complications in current AFLD with those of two decades ago.MethodsWe performed this cross-sectional study in a Japanese health check-up centre. Consecutive participants who visited the facilities between June 1994 and December 1997 or between January 2014 and December 2017 were enrolled. A total of 7499 participants (4804 men, 2695 women) in the past cohort and 20 029 participants (11 676 men, 8353 women) in the current cohort were entered to this study.ResultsThe prevalence of drinkers in the current cohort was significantly lower (4.7%) than that in the past cohort in men (5.9%, pConclusionsAFLD currently tends to be accompanied by hyperglycaemia. The prevalence of fatty liver in drinkers increased in men, although alcoholic consumptions did not increase. We should pay attention to fatty liver combined with hyperglycaemia for individuals who consume alcohol today.

Sensory modalities are essential for navigating through an ever-changing environment. From insects to mammals, transient receptor potential (TRP) channels are known mediators for cellular sensing. Chlamydomonas reinhardtii is a motile single-celled freshwater green alga that is guided by photosensory, mechanosensory, and chemosensory cues. In this type of alga, sensory input is first detected by membrane receptors located in the cell body and then transduced to the beating cilia by membrane depolarization. Although TRP channels seem to be absent in plants, C. reinhardtii possesses genomic sequences encoding TRP proteins. Here, we describe the cloning and characterization of a C. reinhardtii version of a TRP channel sharing key features present in mammalian TRP channels associated with sensory transduction. In silico sequence-structure analysis unveiled the modular design of TRP channels, and electrophysiological experiments conducted on Human Embryonic Kidney-293T cells expressing the Cr-TRP1 clone showed that many of the core functional features of metazoan TRP channels are present in Cr-TRP1, suggesting that basic TRP channel gating characteristics evolved early in the history of eukaryotes.

The composition of the vaginal microbiome, including both the presence of pathogens involved in sexually transmitted infections (STI) as well as commensal microbiota, has been shown to have important associations for a woman’s reproductive and general health. Currently, healthcare providers cannot offer comprehensive vaginal microbiome screening, but are limited to the detection of individual pathogens, such as high-risk human papillomavirus (hrHPV), the predominant cause of cervical cancer. There is no single test on the market that combines HPV, STI, and microbiome screening. Here, we describe a novel inclusive women’s health assay that combines self-sampling with sequencing-based HPV detection and genotyping, vaginal microbiome analysis, and STI-associated pathogen detection. The assay includes genotyping and detection of 14 hrHPV types, 5 low-risk HPV types (lrHPV), as well as the relative abundance of 32 bacterial taxa of clinical importance, includingLactobacillus,Sneathia,Gardnerella, and 4 pathogens involved in STI, with high sensitivity, specificity, and reproducibility. For each of these taxa, healthy ranges were determined in a group of 50 self-reported healthy women. The hrHPV portion of the test was evaluated against the Digene High-Risk HPV HC2 DNA test with vaginal samples obtained from 185 women. Results were concordant for 181/185 of the samples (overall agreement of 97.83%, Cohen’s kappa = 0.93), with sensitivity and specificity values of 94.74% and 98.64%, respectively. Two discrepancies were caused by the Digene assay’s known cross-reactivity with low-risk HPV types, while two additional samples were found to contain hrHPV not detected by Digene. This novel assay could be used to complement conventional cervical cancer screening, because its self-sampling format can expand access among women who would otherwise not participate, and because of its additional information about the composition of the vaginal microbiome and the presence of pathogens.

Potassium channels are membrane proteins that allow fast and selective flow of K+ ions across membranes, participating on the regulation of the electrical properties of the cell, generation and propagation of electrical impulses in nervous systems, gene expression regulation, neurotransmitters release. K+ channels have a selectivity filter (SF) composed by a highly conserved sequence TVGYGD, which forms the narrowest part of the channel. Despite the fact that the structure of the SF is conserved among K+ channels, they show different conductance rates e.g. 250 pS for BK channel and 20 pS for Shaker channel. Moreover, a single mutation in Shaker (P475D) can increase its conductance from 20 pS to 180 pS.Molecular dynamics simulations of the aforementioned K+ channels were performed in order to describe the molecular properties that modulate the conductance process. To analyze these properties an external electric fields were applied, allowing a faster permeation of K+ ions and therefore to have a further approximation of the patch clamp experimental conditions.Using this non-equilibrium approach a number of outward K+ transport events were observed in a high and low conductance K+ channels. The properties involved in the K+ ion conductance process were characterized at molecular level through computing the electrostatic potentials profile, PMF (ABF method) profiles, permeation events number, K+ desolvation process and K+ ion density inside the pore. This study provides new perspectives to understand the ion conductance observed in high and low conductance K+ channels, allowing to propose new hypotheses which were validated through site directed mutagenesis and electrophysiological assays.Acknowledgement: This work was supported by FONDECYT 1131003 (FGN), 1120818 (DN) and CINV (Millenium Initiative, 09-022-F), RS thanks to CONICYT for doctoral scholarship.