1,536 research outputs found
Molecular Analysis of N6-Methyladenine Patterns in \u3cem\u3eTetrahymena thermophila\u3c/em\u3e Nuclear DNA
We have cloned two DNA fragments containing 5\u27-GATC-3\u27 sites at which the adenine is methylated in the macronucleus of the ciliate Tetrahymena thermophila. Using these cloned fragments as molecular probes, we analyzed the maintenance of methylation patterns at two partially and two uniformly methylated sites. Our results suggest that a semiconservative copying model for maintenance of methylation is not sufficient to account for the methylation patterns we found during somatic growth of Tetrahymena. Although we detected hemimethylated molecules in macronuclear DNA, they were present in both replicating and nonreplicating DNA. In addition, we observed that a complex methylation pattern including partially methylated sites was maintained during vegetative growth. This required the activity of a methylase capable of recognizing and modifying sites specified by something other than hemimethylation. We suggest that a eucaryotic maintenance methylase may be capable of discriminating between potential methylation sites to ensure the inheritance of methylation patterns
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Design of a randomized superiority trial of a brief couple treatment for PTSD.
Interpersonal difficulties are common among veterans with posttraumatic stress disorder (PTSD) and are associated with poorer treatment response. Treatment outcomes for PTSD, including relationship functioning, improve when partners are included and engaged in the therapy process. Cognitive-behavioral conjoint therapy for PTSD (CBCT) is a manualized 15-session intervention designed for couples in which one partner has PTSD. CBCT was developed specifically to treat PTSD, engage a partner in treatment, and improve interpersonal functioning. However, recent research suggests that an abbreviated CBCT protocol may lead to sufficient gains in PTSD and relationship functioning, and yield lower dropout rates. Likewise, many veterans report a preference for receiving psychological treatments through clinical videoteleconferencing (CVT) rather than traditional face-to-face modalities that require travel to VA clinics. This manuscript describes the development and implementation of a novel randomized controlled trial (RCT) that examines the efficacy of an abbreviated 8-session version of CBCT ("brief CBCT," or B-CBCT), and compares the efficacy of this intervention delivered via CVT to traditional in-person platforms. Veterans and their partners were randomized to receive B-CBCT in a traditional Veterans Affairs office-based setting (B-CBCT-Office), CBCT through CVT with the veteran and partner at home (B-CBCT-Home), or an in office-delivered, couple-based psychoeducation control condition (PTSD Family Education). This study is the first RCT designed to investigate the delivery of B-CBCT specifically to veterans with PTSD and their partners, as well as to examine the delivery of B-CBCT over a CVT modality; findings could increase access to care to veterans with PTSD and their partners
‘Channel Shift’:technologically-mediated policing and procedural justice
In recent years, police forces in the United Kingdom have introduced various technologies that alter the methods by which they interact with the public. In a parallel development, many forces have also begun to embrace the concept of procedural justice as a method through which to secure legitimacy and (in turn) public compliance and cooperation. What has not received sufficient attention, within policing or academia, is the extent to which these two trends are compatible, with the procedural justice literature still predicated on an assumption that police–public ‘contacts’ or ‘encounters’ are in-person. The effect of technologically mediating police–public contacts on ‘policing by consent’, is therefore unknown. In this article, we focus specifically on the possible implications of the Single Online Home (SOH) (a portal through which the public can report crime, get updates on cases, give feedback and pay fines, among other things, which is currently being rolled out across forces), considering ‘interactions’ between police and public where there is no physical co-presence. Noting the unique context that is policing, we draw on the limited existing research on procedural justice encounters in technologically mediated contexts to explore whether procedural justice theory is ‘future-proof’ for a policing context increasingly reliant on such encounters. We conclude that, through empirical research, we must update our conceptual understanding of what ‘contact’ can mean, and accept that current developments may in fact be transforming relationships rather than simply facilitating existing ones
Estimating Risk from Ambient Concentrations of Acrolein across the United States
BACKGROUND: Estimated ambient concentrations of acrolein, a hazardous air pollutant, are greater than the U.S. Environmental Protection Agency (EPA) reference concentration throughout the United States, making it a concern for human health. However, there is no method for assessing the extent of risk under the U.S. EPA noncancer risk assessment framework. OBJECTIVES: We estimated excess risks from ambient concentrations of acrolein based on dose–response modeling of a study in rats with a relationship between acrolein and residual volume/total lung capacity ratio (RV/TLC) and specific compliance (sC(L)), markers for altered lung function. METHODS: Based on existing literature, we defined values above the 90th percentile for controls as “adverse.” We estimated the increase over baseline response that would occur in the human population from estimated ambient concentrations of acrolein, taken from the U.S. EPA’s National-Scale Air Toxics Assessment for 1999, after standard animal-to-human conversions and extrapolating to doses below the experimental data. RESULTS: The estimated median additional number of adverse sC(L) outcomes across the United States was approximately 2.5 cases per 1,000 people. The estimated range of additional outcomes from the 5th to the 95th percentile of acrolein concentration levels across census tracts was 0.28–14 cases per 1,000. For RV/TLC, the median additional outcome was 0.002 per 1,000, and the additional outcome at the 95th percentile was 0.13 per 1,000. CONCLUSIONS: Although there are uncertainties in estimating human risks from animal data, this analysis demonstrates a method for estimating health risks for noncancer effects and suggests that acrolein could be associated with decreased respiratory function in the United States
Social Services for Sexual Minority Youth: Preferences for What, Where, and How Services are Delivered
As part of an internet-based study to investigate experiences of sexual minority youth in the U.S., 544 youth, ages 14-19, were surveyed about their need for services, where they preferred to receive these services, and their preferred method of service delivery. The survey was anonymous and youth were recruited from LGBTQ-specific listservs and venues as well as through social networking sites as a way of reaching youth often not represented in LGBTQ surveys. Youth highly endorsed many types of services, settings, and modes of delivery. Some subgroup differences emerged. Transgender youth and those uncertain about their gender identity expressed stronger interest than others in services to address stress, family issues, and self-defense, and in receiving support and guidance from LGBTQ adults. Few differences in service preferences along demographic lines such as race/ethnicity emerged; however, African American youth were more likely than others to prefer services offered in a place of worship. Contrary to predictions, geographic and community variables were not related to service type, delivery format, or location preferences
A Latent Class Analysis of Heterosexual Young Men\u27s Masculinities
Parallel bodies of research have described the diverse and complex ways that men understand and construct their masculine identities (often termed masculinities ) and, separately, how adherence to traditional notions of masculinity places men at risk for negative sexual and health outcomes. The goal of this analysis was to bring together these two streams of inquiry. Using data from a national, online sample of 555 heterosexually active young men, we employed latent class analysis (LCA) to detect patterns of masculine identities based on men\u27s endorsement of behavioral and attitudinal indicators of dominant masculinity, including sexual attitudes and behaviors. LCA identified four conceptually distinct masculine identity profiles. Two groups, termed the Normative and Normative/Male Activities groups, respectively, constituted 88Ã¥ % of the sample and were characterized by low levels of adherence to attitudes, sexual scripts, and behaviors consistent with dominant masculinity, but differed in their levels of engagement in male-oriented activities (e.g., sports teams). Only eight percent of the sample comprised a masculinity profile consistent with traditional ideas about masculinity; this group was labeled Misogynistic because of high levels of sexual assault and violence toward female partners. The remaining four percent constituted a Sex-Focused group, characterized by high numbers of sexual partners, but relatively low endorsement of other indicators of traditional masculinity. Follow-up analyses showed a small number of differences across groups on sexual and substance use health indicators. Findings have implications for sexual and behavioral health interventions and suggest that very few young men embody or endorse rigidly traditional forms of masculinity
Predicting Sexual Assault Perpetration Among Heterosexually Active Young Men
Data from an online community sample of young men were analyzed to test predictors of sexual assault perpetration. We used structural equation modeling to test the relative contributions of specific sub-types of childhood adversity to subsequent sexual aggression. Mediators included hostile masculinity, impersonal sexual behavior and attitudes, and substance use variables. Findings suggested that childhood sexual abuse had direct and mediated effects on sexual assault perpetration, but hostile masculinity was the only proximal factor significantly related to aggression. Childhood polytrauma was also associated with increased perpetration risk, suggesting that prevention efforts may be aided by increased attention to childhood maltreatment
Food provisioning increases the risk of injury in a long-lived marine top predator
Funding This publication was supported by the US Department of Commerce's National Oceanic and Atmospheric Administration under NOAA Award NA14OAR4170098, the Mississippi-Alabama Sea Grant Consortium (Project R/MG/BR-15B). Long-term data were collected with additional major support from the Batchelor Foundation, Disney's Worldwide Conservation Fund, Dolphin Quest, Earthwatch Institute and the Chicago Zoological Society. The views expressed herein do not necessarily reflect the views of any of those organizations.Peer reviewedPublisher PD
Patterns Of Intimate Partner Violence And Sexual Risk Behavior Among Young Heterosexually Active Men
Intimate partner violence (IPV) victimization is linked to sexual risk exposure among women. However, less is known about the intersection of IPV perpetration and sexual risk behavior among men. This study used data from a diverse, community sample of 334 heterosexually active young men, aged 18 to 25, across the United States to examine whether and how men with distinct IPV-related behavior patterns differed in sexual riskÃrelated behavior and attitudes. Participants were recruited and surveyed online, and grouped conceptually based on the types of IPV perpetration behavior(s) used in a current or recent romantic relationship. Groups were then compared on relevant sexual risk variables. Men reporting both physical abuse and sexual coercion against intimate partners reported significantly higher numbers of lifetime partners, higher rates of nonmonogamy, greater endorsement of nonmonogamy, and less frequent condom use relative to nonabusive men or those reporting controlling behavior only. This group also had higher sexually transmitted infection (STI) exposure compared to men who used controlling behavior only and men who used sexual coercion only. Findings suggest that interventions with men who use physical and sexual violence need to account for not only the physical and psychological harm of this behavior but also the sexual risk to which men may expose their partners
Human TLR1 Deficiency Is Associated with Impaired Mycobacterial Signaling and Protection from Leprosy Reversal Reaction
Toll-like receptors (TLRs) are important regulators of the innate immune response to pathogens, including Mycobacterium leprae, which is recognized by TLR1/2 heterodimers. We previously identified a transmembrane domain polymorphism, TLR1_T1805G, that encodes an isoleucine to serine substitution and is associated with impaired signaling. We hypothesized that this TLR1 SNP regulates the innate immune response and susceptibility to leprosy. In HEK293 cells transfected with the 1805T or 1805G variant and stimulated with extracts of M. leprae, NF-κB activity was impaired in cells with the 1805G polymorphism. We next stimulated PBMCs from individuals with different genotypes for this SNP and found that 1805GG individuals had significantly reduced cytokine responses to both whole irradiated M. leprae and cell wall extracts. To investigate whether TLR1 variation is associated with clinical presentations of leprosy or leprosy immune reactions, we examined 933 Nepalese leprosy patients, including 238 with reversal reaction (RR), an immune reaction characterized by a Th1 T cell cytokine response. We found that the 1805G allele was associated with protection from RR with an odds ratio (OR) of 0.51 (95% CI 0.29–0.87, p = 0.01). Individuals with 1805 genotypes GG or TG also had a reduced risk of RR in comparison to genotype TT with an OR of 0.55 (95% CI 0.31–0.97, p = 0.04). To our knowledge, this is the first association of TLR1 with a Th1-mediated immune response. Our findings suggest that TLR1 deficiency influences adaptive immunity during leprosy infection to affect clinical manifestations such as nerve damage and disability
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