American indians with substance use disorders: treatment needs and comorbid conditions

Background: American Indians and Alaska Natives (AI/ANs) experience significant disparities in health status and access to care. Furthermore, only limited data are available on substance use, mental health disorders, and treatment needs for this population. Addressing such disparities and developing culturally relevant, effective interventions for AI/AN communities require participatory research. Objectives and Methods: The Western States Node of the National Institute on Drug Abuse Clinical Trials Network partnered with two American Indian substance abuse treatment programs: an urban health center and a reservation-based program to assess client characteristics, drug use patterns, and treatment needs. Data collected by staff members at the respective programs from urban (n = 74) and reservation (n = 121) clients were compared. Additional sub-analysis examined patients reporting regular opioid use and mood disorders. Results: Findings indicate that urban clients were more likely to report employment problems, polysubstance use, and a history of abuse. Reservation-based clients reported having more severe medical problems and a greater prevalence of psychiatric problems. Clients who were regular opioid users were more likely to report having a chronic medical condition, suicidal thoughts, suicide attempts, polysubstance abuse, and IV drug use. Clients who reported a history of depression had twice as many lifetime hospitalizations and more than five times as many days with medical problems. Conclusions: Findings from this project provide information about the patterns of substance abuse and the importance of comprehensive assessments of trauma and comorbid conditions. Results point to the need for integrative coordinated care and auxiliary services for AI/AN clients seeking treatment for substance use disorders.     

Age-related differences in the prevalence and correlates of anxiety in youth with autism spectrum disorders

Age-related differences in the prevalence and correlates of anxiety were cross-sectionally examined in 1316 children and adolescents with autism spectrum disorder (ASD) who presented for initial evaluation at 14 outpatient autism centers around the country and in Canada. The prevalence of clinical and subclinical anxiety as well as the correlates of anxiety were examined in three age groups of children: preschool, school age and adolescents. Findings showed that the prevalence of anxiety in each age group exceeded the prevalence of anxiety in the general population. Adolescents and school age children had the highest prevalence of clinical (40%) and subclinical anxiety (26%), respectively. Higher IQ and less ASD severity were each weakly correlated with more anxiety in preschool and school age children. Affective symptoms were strongly associated with anxiety in each age group. Age specific psychiatric comorbidities were also present. Anxiety was associated with attention deficit hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) symptoms in the preschool group, ODD and somatic symptoms in the school age children, and ADHD symptoms in adolescents. These data underscore the need for prevention and treatment of anxiety as well as research examining the characteristics of anxiety in children with ASD using a developmental framework.     

Collaborative behavioral management among parolees: drug use, crime and re-arrest in the Step'n Out randomized trial

Aims To determine whether collaborative behavioral management (CBM) reduces substance use, crime and re‐arrest among drug‐involved parolees. Design Step'n Out was a randomized behavioral trial of CBM versus standard parole (SP) during 2004–08. CBM adapted evidence‐based role induction, behavioral contracting and contingent reinforcement to provide parole officer/treatment counselor dyads with positive tools in addition to sanctions to manage parolees' behavior over 12 weeks. Setting Six parole offices in five states in the USA. Participants Parolee volunteers with a mandate for addiction treatment and a minimum of 3 months of parole (n = 476). Follow‐up was 94% at 3 months and 86% at 9 months. Measurements Drug use and crime in a given month from calendar interviews 3 and 9 months after parole initiation, and re‐arrests from criminal justice administrative data. Findings The CBM group had fewer months in which they used their primary drug [adjusted risk ratio (ARR) 0.20, 95% confidence interval (CI): 0.05, 0.78, P = 0.02] and alcohol (ARR 0.38, 95% CI: 0.22, 0.66, P = 0.006) over follow‐up. CBM had its greatest effects among parolees who reported marijuana or another ‘non‐hard’ drug as their primary drug; parolees who preferred stimulants or opiates did not benefit. No differences were seen in total crime, re‐arrests or parole revocations. Conclusions Collaborative behavioral management may reduce substance use among primary marijuana or other ‘non‐hard’ drug‐using parolees without increasing revocations. Because the majority of drug violation arrests in the United States are for marijuana, these findings have important implications for the management of a substantial proportion of the US community correctional population.     

Inositol and human reproduction. From cellular metabolism to clinical use

Inositol is an organic compound of high biological importance that is widely distributed in nature. It belongs to the sugar family and is mainly represented by its two dominant stereoisomers: myo-inositol and D-chiro-inositol that are found in the organism in the physiological serum ratio 40:1. Inositol and its derivatives are important components of the structural phospholipids of the cell membranes and are precursors of the second messengers of many metabolic pathways. A high concentration of myoinositol is found in the follicular fluid and in semen. Inositol deficiency and the impairment of the inositol-dependent pathways may play an important role in the pathogenesis of insulin resistance and hypothyroidism. The results of the research also point out the potential beneficial role of inositol supplementation in polycystic ovarian syndrome and in the context of assisted reproduction technologies and in vitro fertilization. The main aim of the article is to overview the major inositol-dependent metabolic pathways and to discuss its importance for reproduction.     

Lipopolysaccharide enhances in vivo interleukin-2 production and proliferation by naive antigen-specific CD4 T cells via a Toll-like receptor 4-dependent mechanism

Microbial adjuvants are essential for the development of T-cell-dependent antibody production, recall T-cell proliferation and interferon-gamma production following immunization with protein antigens. Using an adoptive transfer approach, we showed that the adjuvant lipopolysaccharide enhanced the frequency of cells producing interleukin-2, enhanced clonal expansion by antigen-specific CD4 T cells and increased CD86 and interleukin-1alpha production by antigen-presenting cells. All of these effects were dependent on Toll-like receptor-4 (TLR4) expression by cells other than the antigen-specific CD4 T cells. The ability of lipopolysaccharides to increase the number of antigen-specific CD4 T cells that survive after immunization probably explains the previous finding that antigen-specific proliferation by T cells from normal mice depends on previous exposure to antigen and adjuvant.     

Targeted Disruption of G0/G1 Switch Gene 2 Enhances Adipose Lipolysis,Alters Hepatic Energy Balance,and Alleviates High-Fat Diet–Induced Liver Steatosis

Recent biochemical and cell-based studies identified G₀/G₁ switch gene 2 (G0S2) as an inhibitor of adipose triglyceride lipase (ATGL), a key mediator of intracellular triacylglycerol (TG) mobilization. Here, we show that upon fasting, G0S2 protein expression exhibits an increase in liver and a decrease in adipose tissue. Global knockout of G0S2 in mice enhanced adipose lipolysis and attenuated gain of body weight and adiposity. More strikingly, G0S2 knockout mice displayed a drastic decrease in hepatic TG content and were resistant to high-fat diet (HFD)-induced liver steatosis, both of which were reproduced by liver-specific G0S2 knockdown. Mice with hepatic G0S2 knockdown also showed increased ketogenesis, accelerated gluconeogenesis, and decelerated glycogenolysis. Conversely, overexpression of G0S2 inhibited fatty acid oxidation in mouse primary hepatocytes and caused sustained steatosis in liver accompanied by deficient TG clearance during the fasting-refeeding transition. In response to HFD, there was a profound increase in hepatic G0S2 expression in the fed state. Global and hepatic ablation of G0S2 both led to improved insulin sensitivity in HFD-fed mice. Our findings implicate a physiological role for G0S2 in the control of adaptive energy response to fasting and as a contributor to obesity-associated liver steatosis.     

Molecular mechanisms for the regulation of histone mRNA stem-loop–binding protein by phosphorylation

Replication-dependent histone mRNAs end with a conserved stem loop that is recognized by stem-loop–binding protein (SLBP). The minimal RNA-processing domain of SLBP is phosphorylated at an internal threonine, and Drosophila SLBP (dSLBP) also is phosphorylated at four serines in its 18-aa C-terminal tail. We show that phosphorylation of dSLBP increases RNA-binding affinity dramatically, and we use structural and biophysical analyses of dSLBP and a crystal structure of human SLBP phosphorylated on the internal threonine to understand the striking improvement in RNA binding. Together these results suggest that, although the C-terminal tail of dSLBP does not contact the RNA, phosphorylation of the tail promotes SLBP conformations competent for RNA binding and thereby appears to reduce the entropic penalty for the association. Increased negative charge in this C-terminal tail balances positively charged residues, allowing a more compact ensemble of structures in the absence of RNA.Histone synthesis increases at the beginning of S-phase to package newly replicated DNA with histone proteins, but synthesis must be shut down rapidly and histone mRNA degraded at the end of DNA replication because of the toxicity of surplus histone proteins (1, 2). This cyclic demand for histones requires strict regulation, which is achieved mainly by controlling the synthesis and degradation of histone mRNA (3). Replication-dependent histone mRNAs are the only known cellular mRNAs that are not polyadenylated and instead end with a conserved stem loop (4). Histone mRNAs are generated from longer histone pre-mRNAs as a result of an endonucleolytic cleavage between the stem loop and a purine-rich downstream sequence termed the “histone downstream element” (HDE) (5).Stem-loop–binding protein (SLBP), also known as “hairpin-binding protein” (6), binds to the histone mRNA stem loop, and U7 small nuclear ribonucleoprotein binds to the HDE (7). Other factors, including the endonuclease CPSF-73, are involved in both polyadenylation and histone mRNA 3′-end processing (8–11). In mammalian nuclear extracts, SLBP is not absolutely required for the biochemical reaction of processing (12). In contrast, cleavage of histone pre-mRNA in Drosophila cells and nuclear extracts requires the binding of SLBP to the stem loop (10, 13).The minimal histone mRNA processing domain of Drosophila SLBP contains a 72-aa RNA-binding domain (RBD) unique to SLBPs and an 18-aa C-terminal region (Fig. 1A) (14). This RNA-processing domain (RPD) is necessary and sufficient for histone mRNA 3′-end processing in vitro (15). The RBDs of human SLBP (hSLBP) and Drosophila SLBP (dSLBP) are phosphorylated at a Thr residue in a conserved TPNK motif (16, 17). The recent crystal structure of hSLBP RBD in complex with histone mRNA stem loop and 3′ hExo, a 3′–5′ exonuclease required for histone mRNA degradation, provided the first molecular insights into the architecture of this complex, and revealed how the hSLBP RBD forms a new RNA-binding motif to interact with the stem-loop RNA (18). On the other hand, how SLBP alone interacts with the RNA or how this interaction might be affected by phosphorylation of the TPNK motif is not known.Open in a separate windowFig. 1.Schematic of the domain architecture of dSLBP (Upper) and amino acid sequence alignment of RPDs of Drosophila and human SLBP (Lower). Domains of SLBP include the N-terminal domain (NTD), RBD, and C-terminal region (C). Amino acid sequences are shown with the RBD sequence in the top two rows and the C-terminal region in the bottom row. T230 in the TPNK motif and phosphorylation sites in the C-terminal region are indicated with boldface and asterisks, respectively; the residues involved in RNA binding are shown in cyan; and acidic residues in the C-terminal region are shown in red.The C-terminal region of dSLBP contains a motif, SNSDSDSD, whose hyperphosphorylation is required for efficient processing of histone pre-mRNA (15). Despite the similarity of hSLBP and dSLBP RBDs (55% identical residues) and their ability to bind identical stem-loop RNA sequences, neither SLBP can substitute for the other to process histone pre-mRNA in nuclear extracts; in fact, hSLBP inhibits processing of Drosophila histone pre-mRNA (15). This incompatibility results from differences in the C-terminal region (Fig. 1). The sequence C-terminal to the RBD in hSLBP is required for processing, but it is longer, has no similarity to the Drosophila sequence, and lacks phosphorylation sites.Here we focused on dSLBP and showed that phosphorylation greatly increases dSLBP binding affinity for the histone mRNA stem loop. Mimicking phosphorylation of the dSLBP RPD by mutation of phosphorylation sites to Glu residues at both the TPNK motif and the C-terminal region also boosted binding affinity relative to the nonphosphorylated dSLBP RPD. Structural studies of both the human and Drosophila SLBP RPD indicated that phosphorylation of the TPNK motif stabilizes the RNA-binding domain, but the C-terminal region is flexible in the protein:RNA complex and does not contact the RNA. Instead, we show that the increased negative charge in the C-terminal region of the dSLBP RPD results in a more compact ensemble of protein conformations in the absence of RNA, thereby increasing RNA-binding affinity by reducing the entropy of the unbound protein.     

Predictors of Major Bleeding Among Working-Age Adults with Atrial Fibrillation: Evaluating the Effects of Potential Drug-drug Interactions and Switching from Warfarin to Non-vitamin K Oral Anticoagulants

Purpose

This study aims to evaluate the associations between switching from warfarin to non-vitamin K oral anticoagulants (NOACs), exposure to potential drug-drug interactions (DDIs), and major bleeding events in working-age adults with atrial fibrillation (AF).

Methods

We conducted a retrospective cohort study using the claims database of commercially insured working-age adults with AF from 2010 to 2015. Switchers were defined as patients who switched from warfarin to NOAC; non-switchers were defined as those who remained on warfarin. We developed novel methods to calculate the number and proportion of days with potential DDIs with NOAC/warfarin. Multivariate logistic regressions were utilized to evaluate the associations between switching to NOACs, exposure to potential DDIs, and major bleeding events.

Results

Among a total of 4126 patients with AF, we found a significantly lower number of potential DDIs and the average proportion of days with potential DDIs in switchers than non-switchers. The number of potential DDIs (AOR 1.14, 95% CI 1.02–1.27) and the HAS-BLED score (AOR 1.64, 95% CI 1.48–1.82) were significantly and positively associated with the likelihood of a major bleeding event. The proportion of days with potential DDIs was also significantly and positively associated with risk for bleeding (AOR 1.42, 95% CI 1.03, 1.96). We did not find significant associations between switching to NOACs and major bleeding events.

Conclusions

The number and duration of potential DDIs and patients’ comorbidity burden are important factors to consider in the management of bleeding risk in working-age AF adults who take oral anticoagulants.