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1.
medRxiv ; 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38746260

RESUMO

Background: The prevalence of co-occurring heavy alcohol consumption and obesity is increasing in the United States. Despite neurobiological overlap in the regulation of alcohol consumption and eating behavior, alcohol- and body mass index (BMI)-related phenotypes show no or minimal genetic correlation. We hypothesized that the lack of genetic correlation is due to mixed effect directions of variants shared by AUD and BMI. Methods: We applied MiXeR, to investigate shared genetic architecture between AUD and BMI in individuals of European ancestry. We used conjunctional false discovery rate (conjFDR) analysis to detect loci associated with both phenotypes and their directional effect, Functional Mapping and Annotation (FUMA) to identify lead single nucleotide polymorphisms (SNPs), Genotype-Tissue Expression (GTEx) samples to examine gene expression enrichment across tissue types, and BrainXcan to evaluate the shared associations of AUD and BMI with brain image-derived phenotypes. Results: MiXeR analysis indicated polygenic overlap of 80.9% between AUD and BMI, despite a genetic correlation (r g ) of -.03. ConjFDR analysis yielded 56 lead SNPs with the same effect direction and 76 with the opposite direction. Of the 132 shared lead SNPs, 53 were novel for both AUD and BMI. GTEx analyses identified significant overexpression in the frontal cortex (BA9), hypothalamus, cortex, anterior cingulate cortex (BA24), hippocampus, and amygdala. Amygdala and caudate nucleus gray matter volumes were significantly associated with both AUD and BMI in BrainXcan analyses. Conclusions: More than half of variants significantly associated with AUD and BMI had opposite directions of effect for the traits, supporting our hypothesis that this is the basis for their lack of genetic correlation. Follow-up analyses identified brain regions implicated in executive functioning, reward, homeostasis, and food intake regulation. Together, these findings clarify the extensive polygenic overlap between AUD and BMI and elucidate several overlapping neurobiological mechanisms.

2.
medRxiv ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38645045

RESUMO

There is considerable comorbidity across externalizing and internalizing behavior dimensions of psychopathology. We applied genomic structural equation modeling (gSEM) to genome-wide association study (GWAS) summary statistics to evaluate the factor structure of externalizing and internalizing psychopathology across 16 traits and disorders among European-ancestry individuals (n's = 16,400 to 1,074,629). We conducted GWAS on factors derived from well-fitting models. Downstream analyses served to identify biological mechanisms, explore drug repurposing targets, estimate genetic overlap between the externalizing and internalizing spectra, and evaluate causal effects of psychopathology liability on physical health. Both a correlated factors model, comprising two factors of externalizing and internalizing risk, and a higher-order single-factor model of genetic effects contributing to both spectra demonstrated acceptable fit. GWAS identified 409 lead single nucleotide polymorphisms (SNPs) associated with externalizing and 85 lead SNPs associated with internalizing, while the second-order GWAS identified 256 lead SNPs contributing to broad psychopathology risk. In bivariate causal mixture models, nearly all externalizing and internalizing causal variants overlapped, despite a genetic correlation of only 0.37 (SE = 0.02) between them. Externalizing genes showed cell-type specific expression in GABAergic, cortical, and hippocampal neurons, and internalizing genes were associated with reduced subcallosal cortical volume, providing insight into the neurobiological underpinnings of psychopathology. Genetic liability for externalizing, internalizing, and broad psychopathology exerted causal effects on pain, general health, cardiovascular diseases, and chronic illnesses. These findings underscore the complex genetic architecture of psychopathology, identify potential biological pathways for the externalizing and internalizing spectra, and highlight the physical health burden of psychiatric comorbidity.

3.
Res Sq ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38659902

RESUMO

There is considerable comorbidity across externalizing and internalizing behavior dimensions of psychopathology. We applied genomic structural equation modeling (gSEM) to genome-wide association study (GWAS) summary statistics to evaluate the factor structure of externalizing and internalizing psychopathology across 16 traits and disorders among European-ancestry individuals (n's = 16,400 to 1,074,629). We conducted GWAS on factors derived from well-fitting models. Downstream analyses served to identify biological mechanisms, explore drug repurposing targets, estimate genetic overlap between the externalizing and internalizing spectra, and evaluate causal effects of psychopathology liability on physical health. Both a correlated factors model, comprising two factors of externalizing and internalizing risk, and a higher-order single-factor model of genetic effects contributing to both spectra demonstrated acceptable t. GWAS identified 409 lead single nucleotide polymorphisms (SNPs) associated with externalizing and 85 lead SNPs associated with internalizing, while the second-order GWAS identified 256 lead SNPs contributing to broad psychopathology risk. In bivariate causal mixture models, nearly all externalizing and internalizing causal variants overlapped, despite a genetic correlation of only 0.37 (SE = 0.02) between them. Externalizing genes showed cell-type specific expression in GABAergic, cortical, and hippocampal neurons, and internalizing genes were associated with reduced subcallosal cortical volume, providing insight into the neurobiological underpinnings of psychopathology. Genetic liability for externalizing, internalizing, and broad psychopathology exerted causal effects on pain, general health, cardiovascular diseases, and chronic illnesses. These findings underscore the complex genetic architecture of psychopathology, identify potential biological pathways for the externalizing and internalizing spectra, and highlight the physical health burden of psychiatric comorbidity.

4.
Assessment ; : 10731911241237055, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515003

RESUMO

Given the popularity and ease of single-item craving assessments, we developed a multi-item measure and compared it to common single-item assessments in an ecological momentary assessment (EMA) context. Two weeks of EMA data were collected from 48 emerging adults (56.25% female, 85.42% White) who frequently used cannabis. Eight craving items were administered, and multilevel factor analyses were used to identify the best fitting model. The resulting scale's factors represented purposefulness/general desire and emotionality/negative affect craving. Convergent validity was examined using measures of craving, cannabis use disorder symptoms, frequency of use, cannabis cue reactivity, cannabis use, negative affect, and impulsivity. The scale factors were associated with cue-reactivity craving, negative affect, impulsivity, and subfactors of existing craving measures. For researchers interested in using a single item to capture craving, one item performed particularly well. However, the new scale may provide a more nuanced assessment of mechanisms underlying craving.

5.
Addict Behav ; 153: 107996, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38394959

RESUMO

Early positive subjective effects of cannabis predict the development of cannabis use disorder (CUD). Genetic factors, such as the presence of cytochrome P450 genetic variants that are associated with reduced Δ9-tetrahydrocannabinol (THC) metabolism, may contribute to individual differences in subjective effects of cannabis. Young adults (N = 54) with CUD or a non-CUD substance use disorder (control) provided a blood sample for DNA analysis and self-reported their early (i.e., effects upon initial uses) and past-year positive and negative subjective cannabis effects. Participants were classified as slow metabolizers if they had at least one CYP2C9 or CYP3A4 allele associated with reduced activity. Though the CUD group and control group did not differ in terms of metabolizer status, slow metabolizer status was more prevalent among females in the CUD group than females in the control group. Slow metabolizers reported greater past year negative THC effects compared to normal metabolizers; however, slow metabolizer status did not predict early subjective cannabis effects (positive or negative) or past year positive effects. Post-hoc analyses suggested males who were slow metabolizers reported more negative early subjective effects of cannabis than female slow metabolizers. Other sex-by-genotype interactions were not significant. These initial findings suggest that genetic variation in CYP2C9 and CYP3A4 may have sex-specific associations with cannabis-related outcomes. Slow metabolizer genes may serve as a risk factor for CUD for females independent of subjective effects. Male slow metabolizers may instead be particularly susceptible to the negative subjective effects of cannabis.


Assuntos
Cannabis , Abuso de Maconha , Adulto Jovem , Humanos , Masculino , Feminino , Abuso de Maconha/complicações , Caracteres Sexuais , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP2C9 , Genótipo
6.
Nucleic Acids Res ; 52(2): 831-843, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38084901

RESUMO

The large dsDNA viruses replicate their DNA as concatemers consisting of multiple covalently linked genomes. Genome packaging is catalyzed by a terminase enzyme that excises individual genomes from concatemers and packages them into preassembled procapsids. These disparate tasks are catalyzed by terminase alternating between two distinct states-a stable nuclease that excises individual genomes and a dynamic motor that translocates DNA into the procapsid. It was proposed that bacteriophage λ terminase assembles as an anti-parallel dimer-of-dimers nuclease complex at the packaging initiation site. In contrast, all characterized packaging motors are composed of five terminase subunits bound to the procapsid in a parallel orientation. Here, we describe biophysical and structural characterization of the λ holoenzyme complex assembled in solution. Analytical ultracentrifugation, small angle X-ray scattering, and native mass spectrometry indicate that 5 subunits assemble a cone-shaped terminase complex. Classification of cryoEM images reveals starfish-like rings with skewed pentameric symmetry and one special subunit. We propose a model wherein nuclease domains of two subunits alternate between a dimeric head-to-head arrangement for genome maturation and a fully parallel arrangement during genome packaging. Given that genome packaging is strongly conserved in both prokaryotic and eukaryotic viruses, the results have broad biological implications.


Assuntos
Empacotamento do Genoma Viral , Montagem de Vírus , Montagem de Vírus/genética , Bacteriófago lambda/genética , Endodesoxirribonucleases/metabolismo , DNA , DNA Viral/metabolismo , Empacotamento do DNA
7.
Psychol Addict Behav ; 38(1): 114-123, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36913302

RESUMO

OBJECTIVE: Examine the nature of the relationship between adolescent polysubstance use and high school noncompletion. METHOD: Among a sample of 9,579 adult Australian twins (58.63% female, Mage = 30.59), we examined the association between the number of substances used in adolescence and high school noncompletion within a discordant twin design and bivariate twin analysis. RESULTS: In individual-level models controlling for parental education, conduct disorder symptoms, childhood major depression, sex, zygosity, and cohort, each additional substance used in adolescence was associated with a 30% increase in the odds of high school noncompletion (OR = 1.30 [1.18, 1.42]). Discordant twin models found that the potentially causal effect of adolescent use on high school noncompletion was nonsignificant (OR = 1.19 [0.96, 1.47]). Follow-up bivariate twin models suggested genetic (35.4%, 95% CI [24.5%, 48.7%]) and shared environmental influences (27.8%, 95% CI [12.7%, 35.1%]) each contributed to the covariation in adolescent polysubstance use and early school dropout. CONCLUSIONS: The association between polysubstance use and early school dropout was largely accounted for by genetic and shared environmental factors, with nonsignificant evidence for a potentially causal association. Future research should examine whether underlying shared risk factors reflect a general propensity for addiction, a broader externalizing liability, or a combination of the two. More evidence using finer measurement of substance use is needed to rule out a causal association between adolescent polysubstance use and high school noncompletion. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Transtorno Depressivo Maior , Gêmeos , Adulto , Humanos , Feminino , Adolescente , Criança , Masculino , Austrália/epidemiologia , Gêmeos/genética , Fatores de Risco , Pais
8.
medRxiv ; 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37961309

RESUMO

Background: Adverse childhood events (ACEs) contribute to the development of mood and anxiety disorders and substance dependence. However, the extent to which these effects are direct or indirect and whether genetic risk moderates them is unclear. Methods: We examined associations among ACEs, mood/anxiety disorders, and substance dependence in 12,668 individuals (44.9% female, 42.5% African American/Black, 42.1% European American/White). We generated latent variables for each phenotype and modeled direct and indirect effects of ACEs on substance dependence, mediated by mood/anxiety disorders (forward or "self-medication" model) and of ACEs on mood/anxiety disorders, mediated by substance dependence (reverse or "substance-induced" model). In a sub-sample, we also generated polygenic scores for substance dependence and mood/anxiety disorder factors, which we tested as moderators in the mediation models. Results: Although there were significant indirect effects in both directions, mediation by mood/anxiety disorders (forward model) was greater than by substance dependence (reverse model). Greater genetic risk for substance dependence was associated with a weaker direct effect of ACEs on substance dependence in both the African- and European-ancestry groups (i.e., gene-environment interaction) and a weaker indirect effect in European-ancestry individuals (i.e., moderated mediation). Conclusion: We found greater evidence that substance dependence results from self-medication of mood/anxiety disorders than that mood/anxiety disorders are substance induced. Among individuals at higher genetic risk for substance dependence who are more likely to develop a dependence diagnosis, ACEs exert less of an effect in promoting that outcome. Following exposure to ACEs, multiple pathways lead to mood/anxiety disorders and substance dependence. Specification of these pathways could inform individually targeted prevention and treatment approaches.

9.
Res Sq ; 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37961429

RESUMO

Background: Adverse childhood events (ACEs) contribute to the development of mood and anxiety disorders and substance dependence. However, the extent to which these effects are direct or indirect and whether genetic risk moderates them is unclear. Methods: We examined associations among ACEs, mood/anxiety disorders, and substance dependence in 12,668 individuals (44.9% female, 42.5% African American/Black, 42.1% European American/White). We generated latent variables for each phenotype and modeled direct and indirect effects of ACEs on substance dependence, mediated by mood/anxiety disorders (forward or "self-medication" model) and of ACEs on mood/anxiety disorders, mediated by substance dependence (reverse or "substance-induced" model). In a sub-sample, we also generated polygenic scores for substance dependence and mood/anxiety disorder factors, which we tested as moderators in the mediation models. Results: Although there were significant indirect effects in both directions, mediation by mood/anxiety disorders (forward model) was greater than by substance dependence (reverse model). Greater genetic risk for substance dependence was associated with a weaker direct effect of ACEs on substance dependence in both the African- and European-ancestry groups (i.e., gene-environment interaction) and a weaker indirect effect in European-ancestry individuals (i.e., moderated mediation). Conclusion: We found greater evidence that substance dependence results from self-medication of mood/anxiety disorders than that mood/anxiety disorders are substance induced. Among individuals at higher genetic risk for substance dependence who are more likely to develop a dependence diagnosis, ACEs exert less of an effect in promoting that outcome. Following exposure to ACEs, multiple pathways lead to mood/anxiety disorders and substance dependence. Specification of these pathways could inform individually targeted prevention and treatment approaches.

10.
Psychol Addict Behav ; 37(6): 809-822, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37471012

RESUMO

OBJECTIVE: Cannabis use motives and craving are associated with increased risk for cannabis-related problems and are ideal targets for prevention and early intervention. Patterns of motives and craving reactivity to cannabis cues differ by sex; however, few studies closely examine the relationship between motives and craving and how it may differ by valence (±) across men and women. METHOD: The present study used Cue Reactivity Ecological Momentary Assessment to assess reward (+) and relief (-) craving four semirandom times per day for 2 weeks in a sample of 63 emerging adults (age 18-21; 54% cisgender women; 85.7% White) who frequently use cannabis (≥ 3 times per week). We assessed craving before and after exposure to brief neutral or cannabis image cues and examined within- and between-participant effects of cue type, motives, sex/gender, and their interactions, on postcue cannabis craving. RESULTS: Regardless of cue type, women with high coping motives (-) reported less postcue relief (-) craving, and men with high enhancement motives (+) reported more postcue reward (+) craving. High enhancement motives (+), regardless of sex/gender, were associated with elevated relief (-) craving reactivity to cannabis cues, and women with high coping motives (-) reported elevated reward (+) craving reactivity to cannabis cues. CONCLUSIONS: Sex/gender differences in the relationships between cannabis motives and craving reactivity indicate the value of a more targeted examination of valence (±) of craving experiences in addition to motives for use. Higher levels of precision may better inform interventions for emerging adults at risk for experiencing cannabis-related problems. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Cannabis , Fissura , Humanos , Adulto , Masculino , Feminino , Adolescente , Adulto Jovem , Fatores Sexuais , Caracteres Sexuais , Motivação , Sinais (Psicologia)
11.
Addiction ; 118(1): 167-176, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35815374

RESUMO

BACKGROUND AND AIMS: Previous studies have demonstrated associations between substance use and reduced educational attainment; however, many were unable to account for potential confounding factors like genetics and the rearing environment. In the few studies that controlled for these factors, the substances assessed were limited to alcohol, cannabis, and tobacco. To address these limitations, we examined the relationship between adolescent use of seven kinds of substances, the number of additional substances used, and high school noncompletion within a large sample of Australian twins. DESIGN: A series of two-level generalized mixed effects logistic regressions were conducted to examine associations between adolescent substance use and high school noncompletion. SETTING: Australia. PARTICIPANTS: A total of 9579 adult Australian twins from two cohorts of the Australian Twin Registry. MEASUREMENTS: Assessments of high school completion, childhood major depression, conduct disorder symptoms, substance use initiation, demographics, and parental educational attainment using the Australian version of the Semi-Structured Assessment for the Genetics of Alcoholism. FINDINGS: There were unique within-twin-pair effects of use of sedatives (odds ratio [OR] = 22.39 [95% confidence interval (CI) = 1.18-423.48]) and inhalants/solvents (OR = 10.46 [95% CI = 1.30-84.16]) on high school noncompletion. The number of substances used in adolescence was strongly associated with high school noncompletion across all discordant twin models (ORs from 1.50-2.32, Ps < 0.03). CONCLUSIONS: In Australia, adolescent substance use appears to be associated with early school dropout, with the effects of any given substance largely because of the confounding factors of parental education, childhood conduct disorder symptoms, and use of other substances. Sedatives and inhalants/solvents have effects on high school noncompletion that cannot be explained by polysubstance use or familial factors.


Assuntos
Transtornos Relacionados ao Uso de Substâncias , Adulto , Adolescente , Humanos , Criança , Austrália/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Gêmeos , Hipnóticos e Sedativos , Solventes
12.
J Am Coll Health ; 71(1): 140-146, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-33577429

RESUMO

Objective: The role of simultaneous alcohol and marijuana (SAM) use in the experience of blackouts among college students is unclear. To clarify discrepancies, the current study evaluated whether the association between SAM user status and blackouts was moderated by high-intensity drinking (HID). Participants and Methods: College students (N = 1,224; 63.7% female) reported on their past year experiences of blackout, marijuana use, SAM use, and HID (i.e., drinking at least twice the binge threshold). Results: SAM users had more past year blackouts than non-SAM users, but this effect was only significant among SAM users who had engaged in HID in the past year (nonbinge: F(5,37) = 0.50, p = 0.49; binge: F(5,138) = 0.23, p = 0.63; HID: F(5,328) = 4.52, p = 0.03). Conclusions: Effects of SAM user status on the experience of alcohol-related blackouts may be limited to individuals who engage in HID.


Assuntos
Consumo de Álcool na Faculdade , Cannabis , Fumar Maconha , Uso da Maconha , Transtornos Relacionados ao Uso de Substâncias , Humanos , Feminino , Masculino , Uso da Maconha/epidemiologia , Universidades , Estudantes , Fumar Maconha/epidemiologia , Consumo de Bebidas Alcoólicas/epidemiologia , Etanol
13.
Curr Addict Rep ; 10(4): 628-637, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38264339

RESUMO

Purpose of Review: The aim is to review recent literature on sex and gender differences in patterns of use, motives, pharmacological effects, and consequences of simultaneous alcohol and cannabis use (SAC). Recent Findings: Men engage in SAC more frequently than women. Women may have more substance-specific motives for use, while men tend to consistently endorse social/enhancement motives for both alcohol and cannabis. Regarding pharmacological effects, women experience the same subjective effects as men do at lower levels of use, with some evidence that women modulate cannabis use during simultaneous use episodes to avoid greater subjective intoxication. Finally, women appear more vulnerable to experiencing a range of positive and negative consequences from SAC relative to men. Summary: Research has identified several important sex/gender differences in SAC and its correlates and consequences. However, research has primarily focused on white and cisgender populations, with a need for more research among racial/ethnic and gender minorities.

14.
Curr Addict Rep ; 9(4): 432-444, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36467720

RESUMO

Purpose of Review: Individuals living in rural areas face unique challenges when accessing services for alcohol-related problems and are at increased risk of experiencing alcohol-related harms. We outline research on rural-urban treatment gaps in alcohol use treatment, identify common barriers to treatment, and provide recommendations for how to address the difficulties faced by this population. Recent Findings: Globally, individuals living in rural and remote areas are less likely to receive care for alcohol-related concerns compared to those residing in urban areas. Rural areas suffer from insufficient access to specialty providers, and rural residents are likely to experience greater stigma regarding seeking treatment for alcohol-related concerns. Summary: Given rural-urban disparities in access to treatment for alcohol use concerns, treatment efforts should incorporate stakeholders across the medical system. Telehealth options are particularly promising for increasing access to care. Adaptations should emphasize existing strengths among rural populations, such as strong religious beliefs and close community ties.

15.
Twin Res Hum Genet ; 25(4-5): 187-195, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36189823

RESUMO

Genes associated with educational attainment may be related to or interact with adolescent alcohol, tobacco and cannabis use. Potential gene-environment interplay between educational attainment polygenic scores (EA-PGS) and adolescent alcohol, tobacco, and cannabis use was evaluated with a series of regression models fitted to data from a sample of 1871 adult Australian twins. All models controlled for age, age2, cohort, sex and genetic ancestry as fixed effects, and a genetic relatedness matrix was included as a random effect. Although there was no evidence that adolescent alcohol, tobacco or cannabis use interacted with EA-PGS to influence educational attainment, there was a significant, positive gene-environment correlation with adolescent alcohol use at all PGS thresholds (ps <.02). Higher EA-PGS were associated with an increased likelihood of using alcohol as an adolescent (ΔR2 ranged from 0.5% to 1.1%). The positive gene-environment correlation suggests a complex relationship between educational attainment and alcohol use that is due to common genetic factors.


Assuntos
Cannabis , Adulto , Adolescente , Humanos , Nicotiana , Austrália/epidemiologia , Herança Multifatorial/genética , Escolaridade , Etanol
16.
Clin Psychol Sci ; 10(5): 901-919, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36101707

RESUMO

Gambling disorder is associated with suicidal behaviors, but it is not clear whether the association is due to common etiologic factors or to gambling disorder being causally related to suicidality. This question was examined from epidemiologic, longitudinal, and discordant twin study perspectives. The results suggested that the causes of the association with disordered gambling differed for suicidal ideation, plan, and attempt, and differed for men and women. The association of suicidal thoughts with disordered gambling was non-causally explained by common genetic influences among women (but not men). Conversely, there was evidence consistent with a potentially causal influence of disordered gambling on suicide attempt among men (but not women), which might have been related to gambling-related financial problems. The use of monetary data to identify individuals experiencing financial harms associated with their gambling may represent a more practicable target for screening, intervention, and prevention and may reduce gambling-related financial crises, thereby warding off a potential gambling-related suicide attempt.

17.
J Mol Biol ; 434(19): 167719, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35820453

RESUMO

Capsid assembly pathways are strongly conserved in the complex dsDNA viruses, where major capsid proteins (MCP) self-assemble into icosahedral procapsid shells, chaperoned by a scaffolding protein. Without a scaffold, the capsid proteins aggregate and form aberrant structures. This, coupled with the rapid co-polymerization of MCP and scaffolding proteins, has thwarted characterization of the earliest steps in shell assembly. Here we interrogate the structure and biophysical properties of a soluble, assembly-deficient phage lambda major capsid protein, MCP(W308A). The mutant protein is folded, soluble to high concentrations and binds to the scaffolding protein in an apparent SP2:MCP(W308A)1 stoichiometry but does not assemble beyond this initiating complex. The MCP(W308A) crystal structure was solved to 2.7 Å revealing the canonical HK97 fold in a "pre-assembly" conformation featuring the conserved N-arm and E-loops folded into the body of the protein. Structural, biophysical and computational analyses suggest that MCP(W308A) is thermodynamically trapped in this pre-assembly conformation precluding self-association interactions required for shell assembly. A model is described wherein dynamic interactions between MCP proteins play an essential role in high fidelity viral shell assembly. Scaffold-chaperoned MCP polymerization is a strongly conserved process in all the large dsDNA viruses and our results provide insight into this primordial complex in solution and have broad biological significance in our understanding of virus assembly mechanisms.


Assuntos
Bacteriófago lambda , Proteínas do Capsídeo , Capsídeo , Montagem de Vírus , Bacteriófago lambda/fisiologia , Capsídeo/química , Proteínas do Capsídeo/química , Dobramento de Proteína
18.
Addiction ; 117(3): 690-700, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34342067

RESUMO

BACKGROUND AND AIMS: Previous research has demonstrated phenotypical associations between disordered gambling (DG) and Big 5 personality traits, and a twin study suggested that shared genetic influences accounted for a substantial portion of this relation. The present study examined associations between DG and polygenic scores (PSs) for Big 5 traits to measure the shared genetic underpinnings of Big 5 personality traits and DG. DESIGN: Zero-inflated negative binomial regression models estimated associations between Big 5 PSs and past-year and life-time assessments of DG in a longitudinally assessed population-based birth cohort. SETTING: United Kingdom. PARTICIPANTS: A total of 4729 unrelated children of European ancestry from the Avon Longitudinal Study of Parents and Children (ALSPAC) with both phenotypical and genetic data. MEASUREMENTS: Phenotypical outcomes included past-year assessment of DG using the problem gambling severity index (PGSI) and life-time assessment of DSM-IV pathological gambling symptoms (DPG) across the ages of 17, 20 and 24 years. Polygenic scores were derived for the Big 5 personality traits of agreeableness, extraversion, conscientiousness, openness and neuroticism using summary statistics from genome-wide association studies (GWAS). FINDINGS: PSs for agreeableness [ß= - 0.25, standard error (SE) = 0.054, P = 3.031e-6, ΔR2 = 0.008] and neuroticism (ß=0.14, SE = 0.046, P = 0.0017, ΔR2 = 0.002) significantly predicted PGSI scores over and above included covariates (i.e. sex and first five ancestral principal components). PSs for agreeableness (ß= - 0.20, SE = 0.056, P = 0.00036, ΔR2 = 0.003) and neuroticism, when interactions with age were taken into account (ß = 0.29, SE = 0.090, P = 0.002, ΔR2 = 0.004), also predicted DPG scores. CONCLUSIONS: Polygenic contributions to low agreeableness and high neuroticism appear to predict two measures of disordered gambling (problem gambling severity index and life-time assessment of DSM-IV pathological gambling symptoms). Polygenic scores for neuroticism interact with age to suggest that the positive association becomes stronger from adolescence through young adulthood.


Assuntos
Jogo de Azar , Adolescente , Coorte de Nascimento , Criança , Jogo de Azar/genética , Estudo de Associação Genômica Ampla , Humanos , Estudos Longitudinais , Neuroticismo , Personalidade/genética , Adulto Jovem
19.
Alcohol Clin Exp Res ; 45(5): 1149-1160, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33755998

RESUMO

BACKGROUND: The role of alcohol sensitivity in the experience of blacking out and passing out has not been well established. Here, we examined the relation between individual differences in alcohol sensitivity (i.e., numbers of drinks required to experience various effects of alcohol) and reports of blacking out and passing out in the past year. METHODS: Participants (925 healthy, underage college student drinkers) completed the Alcohol Sensitivity Questionnaire (ASQ) and reported on their past year blacking out and passing out experiences. RESULTS: The fit of the ASQ's 2-factor structure was fair (CFI = 0.90, RMSEA = 0.09) in this sample of underage drinkers. In unadjusted models, higher ASQ scores (i.e., requiring more drinks to experience effects, indicating lower alcohol sensitivity) were associated with experiencing more blackouts (IRR = 1.68 [1.31-2.15]) and passing out (IRR = 2.25 [1.59-3.18]) in the past year. After controlling for typical consumption, however, higher ASQ scores were associated with fewer past-year blackouts (IRR = 0.76 [0.60-0.98]). Total ASQ scores moderated the relationship between typical alcohol consumption and blackout occurrence (interaction IRR = 0.96 [0.93-0.98]), but not passing out occurrence (interaction IRR = 0.95 [0.89-1.01]), with the quantity of alcohol consumed more strongly associated with blackout occurrence among higher-sensitivity than lower-sensitivity drinkers. CONCLUSIONS: These findings are consistent with prior work suggesting that low sensitivity may act as a paradoxical risk factor for certain heavy drinking effects, contributing to higher levels of alcohol consumption and more frequent negative consequences while also conferring protection (relative to high-sensitivity peers) at a given level of alcohol exposure.


Assuntos
Consumo de Álcool na Faculdade , Consumo de Bebidas Alcoólicas/fisiopatologia , Transtornos Relacionados ao Uso de Álcool/fisiopatologia , Transtornos da Memória/fisiopatologia , Consumo de Álcool por Menores , Adolescente , Feminino , Humanos , Masculino , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
20.
AIDS Behav ; 25(1): 49-57, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32856176

RESUMO

To examine HIV service interruptions during the COIVD-19 outbreak in South Carolina (SC) and identify geospatial and socioeconomic correlates of such interruptions, we collected qualitative, geospatial, and quantitative data from 27 Ryan White HIV clinics in SC in March, 2020. HIV service interruptions were categorized (none, minimal, partial, and complete interruption) and analyzed for geospatial heterogeneity. Nearly 56% of the HIV clinics were partially interrupted and 26% were completely closed. Geospatial heterogeneity of service interruption existed but did not exactly overlap with the geospatial pattern of COVID-19 outbreak. The percentage of uninsured in the service catchment areas was significantly correlated with HIV service interruption (F = 3.987, P = .02). This mixed-method study demonstrated the disparity of HIV service interruptions in the COVID-19 in SC and suggested a contribution of existing socioeconomic gaps to this disparity. These findings may inform the resources allocation and future strategies to respond to public health emergencies.


Assuntos
Antirretrovirais/uso terapêutico , COVID-19/psicologia , Continuidade da Assistência ao Paciente/organização & administração , Surtos de Doenças/prevenção & controle , Infecções por HIV/tratamento farmacológico , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Disparidades em Assistência à Saúde , SARS-CoV-2 , Instituições de Assistência Ambulatorial , Antirretrovirais/administração & dosagem , COVID-19/epidemiologia , COVID-19/prevenção & controle , Atenção à Saúde , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Disparidades nos Níveis de Saúde , Humanos , Pandemias , Pesquisa Qualitativa , South Carolina/epidemiologia
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