Site-Specific Glycosylation Analysis of Human and Murine Fcγ Receptor II Family Members Reveals Variant-Specific N-Glycosylation.

Fcγ-receptors (FcγRs) including FcγRII (CD32) gene family members are expressed on leukocytes, bind the crystallizable fragment (Fc) region of immunoglobulin G (IgG), and bridge humoral and cellular immunity. FcγRIIA and FcγRIIB have opposing roles, with the former responsible for activation and the latter for inhibition of immune cell signaling and effector functions. The extracellular domains of human and murine FcγRIIs share multiple conserved N-glycosylation sites. Understanding the role(s) of FcγRIIA and FcγRIIB glycosylation in autoimmune diseases is precluded by a lack of effective methods to study disease-associated changes in glycosylation. To address this barrier, we developed a method to assess site-specific glycosylation of human FcγRIIA and FcγRIIB, and the mouse ortholog of human FcγRIIB. Among the receptors, conserved glycosylation sites are compared, with the N144/145 site displaying predominantly complex glycans in recombinant FcγRIIs. Differences in sialylation between recombinant human FcγRIIA H/R134 (H/R131) variants at a nearby N145 N-glycosylation site are reported. Further, a potential human FcγRIIA O-glycosylation site, S179 (S212), is reported in recombinant FcγRIIA. The robust method to assess site-specific glycosylation of FcγRIIs reported here, can be utilized to study the potential role of FcγRII family glycosylation in disease. Data are available via ProteomeXchange with identifier PXD049429.

Site-Specific Glycosylation Analysis of Murine and Human Fcγ Receptors Reveals High Heterogeneity at Conserved N-Glycosylation Site.

Fc γ-receptors (FcγRs) on leukocytes bind immunoglobulin G (IgG) immune complexes to mediate effector functions. Dysregulation of FcγR-mediated processes contributes to multiple inflammatory diseases, including rheumatoid arthritis, lupus, and immune thrombocytopenia. Critically, immunoregulatory N-glycan modifications on both FcγRs and IgGs alter FcγR-IgG binding affinity. Rapid methods for the characterization of N-glycans across multiple Fcγ receptors are needed to propel investigations into disease-specific contributions of FcγR N-glycans. Here, we utilize nanoliquid chromatography tandem mass spectrometry (nLC-MS/MS) to characterize FcγR glycosylation and report quantitative and site-specific N-glycan characterization of recombinant human FcγRI, FcγRIIIA V158, and FcγRIIIA F158 from CHO cells and murine FcγRI, FcγRIII, and FcγRIV from NS0 cells. Data are available via ProteomeXchange with identifier PXD043966. Broad glycoform distribution (≥30) was observed at mouse FcγRIV site N159 and human FcγRIIIA site N162, an evolutionarily conserved site. Further, mouse FcγRIII N-glycopeptides spanning all four predicted N-glycosylation sequons were detected. Glycoform relative abundances for hFcγRIIIA V/F158 polymorphic variants are reported, demonstrating the clinical potential of this workflow to measure differences in glycosylation between common human FcγRIIIA allelic variants with disease-associated outcomes. The multi-Fcγ receptor glycoproteomic workflow reported here will empower studies focused on the role of FcγR N-glycosylation in autoimmune diseases.

Associations among Trauma Exposure, Post-Traumatic Stress Symptoms and Alcohol Use in Black/African American Treatment-Seeking Adults.

OBJECTIVE: Black/African American (AA) individuals are a group at risk for co-occurring posttraumatic stress disorder (PTSD) symptoms and alcohol use due to unique cultural and system-level barriers. Although associations between trauma exposure, PTSD symptoms, and alcohol use are well established across various populations, Black/AA individuals are underrepresented in this literature, and related findings in this population are inconclusive. Thus, the goal of this study was to examine the associations among trauma exposure, PTSD symptoms, and alcohol use in a sample of treatment-seeking, Black/AA adults. We hypothesized that trauma exposure and alcohol use would be positively associated and that this relationship would be mediated by PTSD symptoms. METHODS: This study conducted secondary analysis of screening data from a PTSD and alcohol use disorder clinical trial. Participants were 96 Black/AA adults (57.3% male; 2.0% Hispanic; M age = 44.73, SD = 11.83) who were seeking treatment for alcohol use and endorsed trauma exposure. Associations between trauma exposure, PTSD symptom severity, and quantity and frequency of alcohol use were tested using bivariate correlations and linear regressions. Hypothesized indirect effects were tested using IBM SPSS Statistics Version 27 PROCESS model 4 with bootstrapping. RESULTS: Findings illustrated a significant positive association between trauma exposure and PTSD symptoms and between PTSD symptoms and drinks per typical drinking day. PTSD symptoms were not significantly associated with number of drinking days. Tests of indirect effects were significant for trauma exposure on drinks per typical drinking day through PTSD symptoms. CONCLUSIONS: Results from the test of indirect effects suggest that among Black/AA adults with heavy alcohol use and trauma exposure, trauma exposure is associated with PTSD symptoms, which in turn is associated with quantity of alcohol use. These findings are consistent with research conducted with White/mixed groups and align with tenets of the self-medication model of PTSD-AUD comorbidity. These findings support current practices that highlight the importance of screening for and addressing PTSD and alcohol use in individuals exposed to trauma. Findings from this paper provide initial data on understudied relationships in an underserved sample and several suggestions are made to generate future research and improve clinical care for Black/AA adults. CLINICAL TRIALS REGISTRY NAME: Pharmacogenetic Treatment With Anti-Glutaminergic Agents for Comorbid PTSD & AUD; ClinicalTrials.gov Identifier: NCT02884908.

FT-GPI, a highly sensitive and accurate predictor of GPI-anchored proteins, reveals the composition and evolution of the GPI proteome in Plasmodium species.

BACKGROUND: Protozoan parasites are known to attach specific and diverse group of proteins to their plasma membrane via a GPI anchor. In malaria parasites, GPI-anchored proteins (GPI-APs) have been shown to play an important role in host-pathogen interactions and a key function in host cell invasion and immune evasion. Because of their immunogenic properties, some of these proteins have been considered as malaria vaccine candidates. However, identification of all possible GPI-APs encoded by these parasites remains challenging due to their sequence diversity and limitations of the tools used for their characterization. METHODS: The FT-GPI software was developed to detect GPI-APs based on the presence of a hydrophobic helix at both ends of the premature peptide. FT-GPI was implemented in C ++and applied to study the GPI-proteome of 46 isolates of the order Haemosporida. Using the GPI proteome of Plasmodium falciparum strain 3D7 and Plasmodium vivax strain Sal-1, a heuristic method was defined to select the most sensitive and specific FT-GPI software parameters. RESULTS: FT-GPI enabled revision of the GPI-proteome of P. falciparum and P. vivax, including the identification of novel GPI-APs. Orthology- and synteny-based analyses showed that 19 of the 37 GPI-APs found in the order Haemosporida are conserved among Plasmodium species. Our analyses suggest that gene duplication and deletion events may have contributed significantly to the evolution of the GPI proteome, and its composition correlates with speciation. CONCLUSION: FT-GPI-based prediction is a useful tool for mining GPI-APs and gaining further insights into their evolution and sequence diversity. This resource may also help identify new protein candidates for the development of vaccines for malaria and other parasitic diseases.

Multidimensional separation and analysis of alpha-1-acid glycoprotein N-glycopeptides using high-field asymmetric waveform ion mobility spectrometry (FAIMS) and nano-liquid chromatography tandem mass spectrometry.

Bottom-up nLC-MS/MS-based glycoprotein mass spectrometry workflows rely on the generation of a mixture of non-glycosylated and glycosylated peptides via proteolysis of glycoproteins. Such methods are challenged by suppression of hydrophilic glycopeptide ions by more abundant, hydrophobic, and readily ionizable non-glycosylated peptides. Commercially available high-field asymmetric waveform ion mobility spectrometry (FAIMS) devices have recently been introduced and present a potential benefit for glycoproteomic workflows by enabling orthogonal separation of non-glycosylated peptides and glycopeptides following chromatographic separation, and prior to MS/MS analysis. However, knowledge is lacking regarding optimal FAIMS conditions for glycopeptide analyses. Here, we document optimal FAIMS compensation voltages for the transmission and analysis of human alpha-1-acid glycoprotein (AGP) tryptic N-glycopeptide ions. Further, we evaluate the effect of FAIMS on AGP glycopeptide assignment confidence by comparing the number of assigned glycopeptides at different confidence levels using a standard nLC-MS/MS method or an otherwise identical method employing FAIMS. Optimized methods will potentiate glycoproteomic analyses by increasing the number of unique glycopeptide identifications and the confidence of glycopeptide assignments. Data are available via ProteomeXchange with identifier PXD036667. Analysis of alpha-1-acid glycoprotein (AGP) tryptic digests via nLC-FAIMS-MS/MS (top) led to the establishment of ideal FAIMS voltages for the analysis of AGP N-glycopeptides (bottom), suggesting that FAIMS can improve the depth of glycoproteome characterization. Pairs of CV magnitudes are shown along the x-axis.

The Effects of Menstrual Cycle Hormones on Responses to Varenicline and Naltrexone Among Female Heavy Drinking Smokers.

AIMS: Women often experience poorer smoking cessation outcomes in comparison to men. Menstrual cycle phase and sex hormones may influence smoking behavior and alter response to opioid antagonist medications. Less is known about the effects of sex hormones in response to pharmacotherapy for female heavy drinking smokers. METHODS: This study is a secondary analysis of premenopausal female heavy drinking smokers who completed a 12-week randomized clinical trial comparing varenicline plus placebo versus varenicline plus naltrexone for smoking cessation and drinking reduction. Participants (n = 26; total observations = 66) provided saliva samples for assays of progesterone (P4) and estradiol (E2) post-randomization at Weeks 4, 8 and 12. We examined the effects of P4/E2 ratio and medication on smoking and drinking outcomes. RESULTS: For drinking outcomes, there was a significant interaction for percent days abstinent (b = 0.017, P = 0.05), suggesting that greater P4/E2 ratio is associated with greater percent days abstinent for women assigned to the varenicline plus naltrexone condition. There were no interaction effects for the remaining drinking outcomes (P's ≥ 0.12). Results found no significant interaction effect of P4/E2 ratio and medication on smoking abstinence (P = 0.19). CONCLUSION: Our results imply that when women show a greater P4/E2 ratio, typically observed during the luteal phase of the menstrual cycle, they experience an added benefit of naltrexone, versus placebo, for drinking outcomes as shown by greater percent days abstinent. Additional studies in larger samples are warranted as sex hormones offer important information above and beyond comparing women versus men.

A Scoping Review of Gender, Sex and Sexuality Differences in Polysubstance Use in Adolescents and Adults.

BACKGROUND: Polysubstance use is a common, problematic behavior that increases risk of harm to self and others. Research suggests that rates may vary based on gender, sex and sexuality. Understanding the current state of this literature may inform prevention and treatment of polysubstance use, leading to reduced public health burden. OBJECTIVES: This review aimed to synthesize research on gender, sex and sexuality differences in polysubstance use in adults and adolescents. METHODS: A scoping review was conducted using all EBSCO databases, PubMed and Google Scholar to identify articles examining the effects of gender, sex and sexuality on polysubstance use. Polysubstance use was defined broadly as the use of any combination of substances over any time period and included licit (alcohol, tobacco) and illicit substances, concurrent and simultaneous use, from lifetime to daily use and use at any frequency. Studies were considered if they were published in peer-reviewed journals between January 1990 and October 2020 and were written in English. Publicly available data sources were also utilized to fully capture prevalence data that has not been published elsewhere. RESULTS: Findings were mostly inconsistent and often conflicting. Only two findings were generally consistent: adult men were overall more likely to report polysubstance use than adult women, and sexual and gender minorities report more frequent polysubstance use than non-minorities. CONCLUSIONS: Research has been unable to clearly elucidate differences in polysubstance use prevalence and patterns according to gender, sex and sexuality. Several recommendations are offered to advance future research and address limitations of current research.

A meta-regression of methodological features that predict the effects of medications on the subjective response to alcohol.

BACKGROUND: Alcohol administration paradigms have been used for early efficacy testing of novel compounds for alcohol use disorder (AUD). There has been an ongoing debate about sample characteristics and methodological features that affect the likelihood of detecting an early efficacy signal for AUD medications. We conducted a meta-regression to test whether the drinking level of the study sample and the peak breath alcohol concentration (BrAC) in the alcohol administration study predict the efficacy of AUD pharmacotherapies on the subjective responses to alcohol. METHODS: We computed the effects of 21 medications on alcohol-induced stimulation, sedation, negative mood, and craving during alcohol administration in 49 studies. RESULTS: Meta-regression analyses indicated a significant and positive effect of pre-study drinks per month on alcohol-induced stimulation (ß = 0.142, p < 0.0001), such that as drinking increases, the benefit of medication over placebo decreases. There was an effect of drinks per month on negative mood (ß = -0.164, p = 0.0248), such that at higher levels of drinks per month, the effects of medications on negative mood are stronger. For sedation, there was an effect of peak BrAC (ß = 0.119, p = 0.0002), such that at low levels of peak BrAC, the effects of medication on sedation were null. For craving, there was a peak BrAC × drinks per month interaction such that at low levels of BrAC, a heavier drinking sample is required to detect the effects of medication on craving. Sensitivity analyses comparing naltrexone studies and non-naltrexone studies suggested that naltrexone was less sensitive to drinks per month across subjective response domains. CONCLUSIONS: These analyses show that design features are critical in studies that test the effects of medications on the subjective responses to alcohol. By specifying the significance and directionality of these effects, as well as the specific points in BrAC or drinks per month at which medication effects are detectable, the study offers recommendations for design features of alcohol administration studies that aim to inform AUD medication development.

Geographic variation of mercury in breeding tidal marsh sparrows of the northeastern United States.

Saltmarsh sparrows (Ammospiza caudacuta) and seaside sparrows (A. maritima) are species of conservation concern primarily due to global sea-level rise and habitat degradation. Environmental mercury (Hg) contamination may present additional threats to their reproductive success and survival. To assess site-specific total mercury (THg) exposure and identify environmental correlates of THg detection, we sampled blood from adult male saltmarsh and seaside sparrows at 27 sites between Maine and Virginia, USA. The mean THg concentration (±1 SD) throughout the entire sampling range was 0.531 ± 0.287 µg/g wet weight (ww) for saltmarsh sparrows and 0.442 ± 0.316 µg/g ww for seaside sparrows. Individual THg concentrations ranged from 0.135-1.420 µg/g ww for saltmarsh sparrows and 0.153-1.530 µg/g ww for seaside sparrows. Model averaging from a suite of linear mixed models showed that saltmarsh sparrows averaged 20.1% higher blood THg concentrations than seaside sparrows, potentially due to differences in diet or foraging behavior. We found no evidence for a relationship between sparrow THg concentrations and land cover surrounding sampled marshes or average precipitation-based Hg deposition. Overall, our results suggest considerable, unexplained variation in tidal marsh sparrow blood THg concentrations over their co-occurring breeding ranges.

A Narrative Literature Review of the Epidemiology, Etiology, and Treatment of Co-Occurring Panic Disorder and Opioid Use Disorder.

OBJECTIVE: Panic disorder is a debilitating psychiatric disorder that often co-occurs with substance use disorders. Given the current opioid epidemic, the high reported rates of comorbid panic disorder and opioid use disorder are particularly concerning. In this narrative review, we describe the literature on panic disorder and opioid use disorder co-occurrence. METHODS: 86 studies, 26 reviews, 2 commentaries, and 5 guidelines pertaining to opioid use disorder, panic disorder, and their comorbidity were identified using all EBSCO databases, PubMed, and Google Scholar. RESULTS: First, we review epidemiological literature on the prevalence of the comorbid condition above and beyond each disorder on its own. Additionally, we discuss the challenges that complicate the differential diagnosis of panic disorder and opioid use disorder and contribute to difficulties establishing rates of comorbidity. Second, we review three theoretical models that have been proposed to explain high rates of co-occurring panic disorder and opioid use disorder: the precipitation hypothesis, the self-medication hypothesis, and the shared vulnerability hypothesis. Third, we outline how co-occurring panic and opioid use disorder may impact treatment for each condition. CONCLUSION: Based on findings in the field, we provide recommendations for future research as well as treatment considerations for co-occurring panic and opioid use disorders.

Lack of Association between Opioid-Receptor Genotypes and Smoking Cessation Outcomes in a Randomized, Controlled Naltrexone Trial.

AIMS: The present study examined how variation in mu- (OPRM1), kappa- (OPRK), and delta- (OPRD) opioid receptor genes may influence the efficacy of naltrexone in the context of a smoking cessation trial. METHODS: The study's primary objective was to examine the association of the Asn40Asp OPRM1 single nucleotide polymorphism (SNP) with naltrexone's effects on smoking quit rate, weight gain, and heavy drinking behavior during a double-blind, randomized clinical trial in 280 adult DSM-IV nicotine-dependent participants. The secondary goal of the study was to examine the relationship of 20 additional SNPs of OPRM1, OPRK, and OPRD with the aforementioned outcomes. RESULTS: Results indicated a null association between any opioid-receptor gene SNP and naltrexone's effects on smoking quit rate, weight gain, and heavy drinking behavior in this sample of nicotine dependent participants. CONCLUSIONS: In sum, these results do not suggest that genetic variation in opioid-receptors is related to treatment responses to naltrexone in a smoking cessation trial.

Naltrexone effects on subjective responses to alcohol in the human laboratory: A systematic review and meta-analysis.

Naltrexone (NTX) has been widely studied for the treatment of alcohol use disorder with overall support for its efficacy. The mechanisms of action of naltrexone are thought to involve attenuation of the hedonic effects of alcohol and potentiation of its aversive effects. In order to provide a quantitative estimate of the effects of naltrexone on subjective response to alcohol, the aims of this meta-analytic review are to examine the effects of naltrexone across four domains of subjective response. Meta-analyses of naltrexone effects on alcohol craving (k = 16, N = 686), stimulation (k = 15, N = 675), sedation (k = 18, N = 777), and negative mood (k = 9, N = 281) suggested that under laboratory conditions and compared with placebo, naltrexone reduces craving (Hedges g = -0.252; SE = 0.054; 95% CI, -0.375 to -0.130; P < 0.01), reduces stimulation (g = -0.223; SE = 0.067; 95% CI, -0.372 to -0.074; P < 0.01), increases sedation (g = 0.251; SE = 0.064; 95% CI, 0.112-0.389; P < 0.01), and increases negative mood (g = 0.227; SE = 0.047; 95% CI, 0.100-0.354; P < 0.01). Results were robust when drinks per month and alcohol dose were added to the models as covariates. The effects of naltrexone varied by severity of alcohol use with medication effects on craving and stimulation being observed in sample of both heavy drinkers and AUD individuals. These results are consistent with the hypothesized mechanisms of action of NTX, although the effects are of small magnitude. This meta-analysis aggregates across multiple human laboratory studies of NTX's effects on subjective response to alcohol, providing a comprehensive summary of a key mechanism of NTX efficacy, namely, alteration of the subjective experience of alcohol.

DisProt 7.0: a major update of the database of disordered proteins.

The Database of Protein Disorder (DisProt, URL: www.disprot.org) has been significantly updated and upgraded since its last major renewal in 2007. The current release holds information on more than 800 entries of IDPs/IDRs, i.e. intrinsically disordered proteins or regions that exist and function without a well-defined three-dimensional structure. We have re-curated previous entries to purge DisProt from conflicting cases, and also upgraded the functional classification scheme to reflect continuous advance in the field in the past 10 years or so. We define IDPs as proteins that are disordered along their entire sequence, i.e. entirely lack structural elements, and IDRs as regions that are at least five consecutive residues without well-defined structure. We base our assessment of disorder strictly on experimental evidence, such as X-ray crystallography and nuclear magnetic resonance (primary techniques) and a broad range of other experimental approaches (secondary techniques). Confident and ambiguous annotations are highlighted separately. DisProt 7.0 presents classified knowledge regarding the experimental characterization and functional annotations of IDPs/IDRs, and is intended to provide an invaluable resource for the research community for a better understanding structural disorder and for developing better computational tools for studying disordered proteins.

Classification of ß-hairpin repeat proteins.

In recent years, a number of new protein structures that possess tandem repeats have emerged. Many of these proteins are comprised of tandem arrays of ß-hairpins. Today, the amount and variety of the data on these ß-hairpin repeat (BHR) structures have reached a level that requires detailed analysis and further classification. In this paper, we classified the BHR proteins, compared structures, sequences of repeat motifs, functions and distribution across the major taxonomic kingdoms of life and within organisms. As a result, we identified six different BHR folds in tandem repeat proteins of Class III (elongated structures) and one BHR fold (up-and-down ß-barrel) in Class IV ("closed" structures). Our survey reveals the high incidence of the BHR proteins among bacteria and viruses and their possible relationship to the structures of amyloid fibrils. It indicates that BHR folds will be an attractive target for future structural studies, especially in the context of age-related amyloidosis and emerging infectious diseases. This work allowed us to update the RepeatsDB database, which contains annotated tandem repeat protein structures and to construct sequence profiles based on BHR structural alignments.

Accurate template-based modeling in CASP12 using the IntFOLD4-TS, ModFOLD6, and ReFOLD methods.

Our aim in CASP12 was to improve our Template-Based Modeling (TBM) methods through better model selection, accuracy self-estimate (ASE) scores and refinement. To meet this aim, we developed two new automated methods, which we used to score, rank, and improve upon the provided server models. Firstly, the ModFOLD6_rank method, for improved global Quality Assessment (QA), model ranking and the detection of local errors. Secondly, the ReFOLD method for fixing errors through iterative QA guided refinement. For our automated predictions we developed the IntFOLD4-TS protocol, which integrates the ModFOLD6_rank method for scoring the multiple-template models that were generated using a number of alternative sequence-structure alignments. Overall, our selection of top models and ASE scores using ModFOLD6_rank was an improvement on our previous approaches. In addition, it was worthwhile attempting to repair the detected errors in the top selected models using ReFOLD, which gave us an overall gain in performance. According to the assessors' formula, the IntFOLD4 server ranked 3rd/5th (average Z-score > 0.0/-2.0) on the server only targets, and our manual predictions (McGuffin group) ranked 1st/2nd (average Z-score > -2.0/0.0) compared to all other groups.

Overcoming the "Valley of Death" in Medications Development for Alcohol Use Disorder.

As the development of novel pharmacotherapies for alcohol use disorder (AUD) has been slow, the discovery and testing of more efficacious pharmacotherapies for AUD represent a high priority research area. In fact, the transition from preclinical to clinical testing of novel compounds has been termed the "valley of death" in medications development. One key obstacle consists of the lack of an articulated set of goals for each stage of medications development. Specifically, the knowledge outputs required to make the transition from safety testing, to early efficacy detection, to confirming clinical efficacy remain unclear, and this is despite a great deal of interest and substantial financial investment in developing novel therapeutics for AUD. This qualitative critical review seeks to draw parallels and lessons from the well-established stage model for behavioral therapies research with alcohol and other substance use disorders and to apply these insights into AUD pharmacotherapy development. We argue that human laboratory models and/or pilot randomized controlled trials should serve as intermediaries in the transition from preclinical studies to large, and costly, randomized controlled efficacy trials. The relative strengths and weaknesses of pilot clinical trials versus human laboratory studies for bridging the "valley of death" are discussed and explored via a Monte Carlo data simulation study. Multiple permutations of suitable research designs informed by the behavioral therapies development model are discussed with the overall goal of promoting consilience and maximizing efficiency across all phases of clinical testing of novel AUD pharmacotherapies.

Pharmacogenetic Effects of Naltrexone in Individuals of East Asian Descent: Human Laboratory Findings from a Randomized Trial.

BACKGROUND: Genetic variation in the endogenous opioid system has been identified as 1 potential source of individual variability in naltrexone treatment outcomes. The majority of naltrexone pharmacogenetic studies have focused on a particular single nucleotide polymorphism (SNP) of the mu-opioid receptor gene (OPRM1; rs1799971; commonly known as the Asn40Asp SNP) in Caucasian samples with decidedly mixed results. The goal of this study was to test the pharmacogenetic effects of naltrexone on subjective response to alcohol and self-administration of alcohol in individuals of East Asian descent. We hypothesized that naltrexone, compared with placebo, would potentiate the aversive and sedative effects of alcohol and reduce alcohol self-administration to a greater extent in Asp40 carriers. METHODS: Participants (N = 77; Asn40Asn, n = 29; Asn40Asp, n = 34, and Asp40Asp, n = 14) completed 2 double-blinded and counterbalanced experimental sessions: one after taking naltrexone (50 mg/d) for 5 days and one after taking matched placebo for 5 days. In each experimental session, participants received a priming dose of intravenous alcohol up to the breath alcohol concentration target of 0.06 g/dl which was immediately followed by an alcohol self-administration period (1 hour). RESULTS: There were no pharmacogenetic effects observed for alcohol-induced stimulation, sedation, craving for alcohol, or alcohol self-administration in the laboratory. During the self-administration period, Asp40 carriers consumed fewer drinks and had a longer latency to first drink as compared to Asn40 homozygotes. CONCLUSIONS: These findings in East Asians add to the mixed literature on naltrexone pharmacogenetics from predominantly Caucasian samples and highlight the complexity of these effects and their overall limited replicability. It is plausible that a consistent pharmacogenetic effect in tightly controlled preclinical and experimental medicine models "fades" in more complex and heterogeneous settings and samples.

Functional analysis of Plasmodium falciparum subpopulations associated with artemisinin resistance in Cambodia.

BACKGROUND: Plasmodium falciparum malaria is one of the most widespread parasitic infections in humans and remains a leading global health concern. Malaria elimination efforts are threatened by the emergence and spread of resistance to artemisinin-based combination therapy, the first-line treatment of malaria. Promising molecular markers and pathways associated with artemisinin drug resistance have been identified, but the underlying molecular mechanisms of resistance remains unknown. The genomic data from early period of emergence of artemisinin resistance (2008-2011) was evaluated, with aim to define k13 associated genetic background in Cambodia, the country identified as epicentre of anti-malarial drug resistance, through characterization of 167 parasite isolates using a panel of 21,257 SNPs. RESULTS: Eight subpopulations were identified suggesting a process of acquisition of artemisinin resistance consistent with an emergence-selection-diffusion model, supported by the shifting balance theory. Identification of population specific mutations facilitated the characterization of a core set of 57 background genes associated with artemisinin resistance and associated pathways. The analysis indicates that the background of artemisinin resistance was not acquired after drug pressure, rather is the result of fixation followed by selection on the daughter subpopulations derived from the ancestral population. CONCLUSIONS: Functional analysis of artemisinin resistance subpopulations illustrates the strong interplay between ubiquitination and cell division or differentiation in artemisinin resistant parasites. The relationship of these pathways with the P. falciparum resistant subpopulation and presence of drug resistance markers in addition to k13, highlights the major role of admixed parasite population in the diffusion of artemisinin resistant background. The diffusion of resistant genes in the Cambodian admixed population after selection resulted from mating of gametocytes of sensitive and resistant parasite populations.