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OBJECTIVE The aim of this study was to identify gene variants of DAT1 (SLC6A3) that modulate subjective responses to acute cocaine exposure. METHODS Non-treatment-seeking volunteers (n=66) with cocaine use disorders received a single bolus infusion of saline and cocaine (40 mg, intravenous) in a randomized order. Subjective effects were assessed with visual analog scales administered before (-15 min) and up to 20 min after infusion. Ratings of subjective effects were normalized to baseline, and saline infusion values were subtracted. Data were analyzed using repeated measures analysis of variance. DNA from the participants was genotyped for the DAT1 intron 8 (rs3836790) and 3'-untranslated region (rs28363170) variable number of tandem repeats. RESULTS Participants were mostly male (∼80%) and African American (∼70%). No differences were found among drug use variables between groups for either polymorphism. Carriers of the 9-allele of the DAT1 3'-untranslated region (9,9 and 9,10) exhibited greater responses to cocaine for 'high', 'any drug effect', 'anxious', and 'stimulated' (all P-values

Dynorphins, the endogenous ligands for the κ opioid receptor, are implicated in neuropsychiatric disorders through modulation of basal and stimuli-induced dopaminergic, glutamatergic, and serotonergic tones. Expression of the prodynorphin gene (PDYN) is critical for rewarding properties of drugs of abuse and stress-induced responses. Epigenetic factors, such as DNA methylation, play an important role in modulation of gene expression.We analyzed DNA methylation patterns of three CpG-rich regions of PDYN, a CpG island, and cluster A in the proximal promoter, and cluster B in coding exon 4, by bisulfite sequencing of DNA from the caudate and anterior cingulate cortex from post-mortem brain of 35 individuals (22 HIV seropositive), and in peripheral blood mononuclear cells from 21 of these individuals.We found remarkably similar patterns of methylation across CpG sites in these tissues. However, there were tissue-specific differences in methylation levels (P=0.000001) of the CpG island: higher levels in peripheral blood mononuclear cells (82%) than in the brain tissues, the caudate (62%), and the anterior cingulate cortex (44%). But there was higher PDYN expression in the caudate than in the anterior cingulate cortex. In contrast, cluster A near the transcription start site is hypomethylated.This DNA methylation profile of the PDYN gene is typical for primary responsive genes with regulatory elements for both basal and tissue-specific transcription. Our findings provide a rationale for further studies of the role of other epigenetic factors in the regulation of PDYN expression in individuals with psychiatric and neurological disorders.

OBJECTIVES We have used genome-wide association studies to identify variants that are associated with vulnerability to develop heroin addiction. METHODS DNA from 325 methadone stabilized, former severe heroin addicts and 250 control individuals were pooled by ethnicity (Caucasian and African-American) and analyzed using the Affymetrix GeneChip Mapping 100 K Set. Genome-wide association tests were conducted. RESULTS The strongest association with vulnerability to develop heroin addiction, with experiment-wise significance (P=0.035), was found in Caucasians with the variant rs10494334, a variant in an unannotated region of the genome (1q23.3). In African Americans, the variant most significantly associated with the heroin addiction vulnerability was rs950302, found in the cytosolic dual specificity phosphatase 27 gene DUSP27 (point-wise P=0.0079). Furthermore, analysis of the top 500 variants with the most significant associations (point-wise P< or =0.0036) in Caucasians showed that three of these variants are clustered in the regulating synaptic membrane exocytosis protein 2 gene RIMS2. Of the top 500 variants in African-Americans (point-wise P< or =0.0238), three variants are in the cardiomyopathy associated 3 gene CMYA3. CONCLUSION This study identifies new genes and variants that may increase an individual's vulnerability to develop heroin addiction.

The OPRL1 gene encodes the nociceptin/orphanin FQ receptor, which plays a role in regulating tolerance and behavioral responses to morphine. However, there is limited information on whether variants of OPRL1 are associated with vulnerability to develop opiate addiction. In this study, we examined five variants of OPRL1 and their role in determining vulnerability to develop opiate addiction.We recruited 447 individuals: 271 former severe heroin addicts and 176 healthy controls. Using a 5'-fluorogenic exonuclease assay, we genotyped individuals at five variants in OPRL1. It was then determined whether there was a significant association of allele, genotype, or haplotype frequency with vulnerability to develop opiate addiction.When the cohort was stratified by ethnicity, we found that, in Caucasians but not in African-Americans or Hispanics, the allele frequency of rs6090041 and rs6090043 were significantly associated point-wise with opiate addiction (P=0.03 and 0.04, respectively). Of the haplotypes formed by these two variants, one haplotype was found to be associated with protection from developing opiate addiction in both African-Americans (point-wise P=0.04) and Caucasians (point-wise P=0.04), and another haplotype with vulnerability to develop opiate addiction in Caucasians only (P=0.020).This study provides evidence for an association of two variants of the OPRL1 gene, rs6090041 and rs6090043, with vulnerability to develop opiate addiction, suggesting a role for nociceptin/orphanin FQ receptor in the development of opiate addiction.

Sunflower (Helianthus annuus L) production has increased in the central Great Plains, but little is known regarding how this crop will affect surface biomass production, various soil quality indicators, and subsequent winter wheat (Triticum aestivum L.) yields. We hypothesized that sunflower production was reducing soil quality relative to other summer crops because of the need for tillage to incorporate herbicide, thus reducing surface residue. Our objectives were to quantify on a Weld silt loam (fine, smectitic, mesic, Aridic Argiustolls) surface crop residue levels immediately after seeding wheat, subsequent wheat grain yield, soil organic carbon (SOC), particulate organic matter-carbon (POM-C), aggregate stability, and texture in 3- or 4-year rotation. A randomized complete block design with three replications was used to compare rotations both with and without sunflower. Our data showed 13% lower SOC content and 26% lower POM-C content at the 0- to 5-cm depth in rotations with sunflower versus those without. At the 5- to 15- cm depths, differences were not significant (P < 0.05). Crop residue by mass was 5 times lower and wheat yields 33% lower in rotations with sunflower, but no differences were measured for wind erodible aggregates or texture. Tillage to incorporate herbicides for sunflower and low amounts of residue after sunflower in the 3-year rotation contributed to reduced SOC and POM-C, decreased residue at wheat planting, and reduced wheat yield. If sunflower is to be included in the central Great Plains, efforts should be made to use no-till production practices and 4-year rotations with corn.

One of the major clinical problems faced in treating posttraumatic stress disorder (PTSD) is that no single treatment is effective for every individual. With the efficacy of medications being questioned (Ipser and Stein, 2012) and the suggestion that evidence-based psychotherapies reduce rather than remit PTSD symptoms (Steenkamp and Litz, 2013), finding ways to predict who may positively respond to a particular treatment is imperative to mitigate PTSD’s negative consequences. The dopamine β-hydroxylase (DBH) gene has a functional polymorphism, rs1611115 (known as -1021C->T or C-970T), with higher plasma activity being associated with the CC genotype in Veterans without versus those with PTSD, while the DβH activity was similar among T allele genotype Veterans, with the CC genotype having overall greater activity than the T carrier genotypes (Mustapic et al., 2007). This suggests PTSD attenuates DβH activity in the higher functioning CC genotype but not in the lower functioning T carrier genotypes; possibly representing a compensatory response to prolonged PTSD hyperarousal. Nepicastat is a potent, competitive, and selective DβH inhibitor selected for study because it decreases norepinephrine (NE) more potently and specifically than disulfiram (Stanley et al., 1997). Nepicastat, like disulfiram, should reduce the abnormally high NE activity generally found in PTSD and result in reduced PTSD hyper-arousal symptoms. The purpose of this study was to compare the utility of using genetics versus functional NE biology to predict who may respond to nepicastat. This was a 6-week randomized, double-blind, multi-site, placebo-controlled study involving 22 OEF/OIF Veterans with PTSD, approved by each site’s IRB and R&D Committees. Measures included the Clinician Administered PTSD Scale – D (hyperarousal) subscale (CAPS-D), DBH genotype, and 24-hour urinary 3-methoxy-4-hydroxyphenylglycol (MHPG) sulfate form representing intra-neuronal noradrenergic metabolism (Filser et al., 1988). All participants who returned for at least one post-randomization visit (12 nepicastat and 10 placebo) were included in the intent-to-treat analysis. The primary efficacy measurement was the change in CAPS-D scores from pre- to post-treatment with the last observation carried forward. Sample consisted of 14 CC and 8 T carriers, was 45.5% White, 54.5% African-American. Alpha was retained at .05. The two treatment groups did not differ for any demographic or psychiatric co-morbid condition, or genotype (all P ≥ .080). Using a pre-post treatment repeated measure ANCOVA, controlling for ethnicity, we identified no direct treatment effect (P = .567) but did find a significant DBH genotype effect (P = .020) with the CC genotype showing greater change than the T carrier genotypes. There was no treatment by genotype interaction (P = .584). In comparison, there were no correlations between the MHPG-sulfate values and CAPS-D scores, whether examined pre-treatment, post-treatment, or for pre-post treatment changes (P > .05). Our findings suggest that a functional genetic marker for DBH may be more useful than using state-dependent measures of noradrenergic activity for predicting an individual's change in PSTD symptomatology. More generally, our results suggest further investigation is warranted to determine if using specific genetic polymorphisms are more useful than functional biologic measures in predicting an individual’s response to other targeted interventions.

The purpose of this study was to evaluate the validity and reliability of the Futrex 5000A near infrared (NIR) spectrophotometer for the assessment of body composition in children and adolescents. Forty-eight subjects (24 boys and 24 girls) with a mean age of 12.7 +/- 2.7 yr underwent three methods of body composition testing: NIR, densitometry by hydrostatic weighing (HYDRO), and skinfold anthropometry (SKF). Percent body fat (%BF) and fat free mass (FFM) derived from the Lohman's age-adjusted Siri equation served as the criterion. Within session test-retest reliability was determined for the NIR device for all subjects and between-week reliability was evaluated for all test methods in 14 subjects. Based on the excellent within- and between-session reliability (ICC ranged from 0.907-0.999), the system offers the potential of obtaining longitudinal data in growth and development studies. However, the significant mean differences, moderate correlations with the criterion (r = 0.62-0.71) and inflated standard errors of estimate (SEE = 4.9-5.5% BF, 2.2-2.9 kg FFM) and total prediction errors (TE = 5.5-8.0% BF, 2.7-3.7 kg FFM) indicate that refinement of prediction equations is needed to establish the measurement validity. Continued research with expanded populations is needed to further demonstrate and evaluate the utility of this device.

Prior to sexual maturation, children and adolescents have more water and less bone mineral content than adults, resulting in less dense fat-free body mass (FFM). This suggests that previously established adult skinfold/density equations are inappropriate for use with children and adolescents for the prediction of body fatness (%BF) and FFM. To overcome this problem, Slaughter and colleagues have introduced new skinfold (SKF) equations that take into account the changing density of FFM in children and adolescents as they mature. The purpose of our study was to cross-validate a select set of the Slaughter SKF equations by comparing them with a criterion measurement (Lohman's Siri age-adjusted body density equation) in 122 subjects ranging in sexual maturation from pre- to post-pubescent and ranging in age from 8-17. Our cross-validation found very high intraclass (reliability) correlations (ICCs = 0.98-0.99) and high validity correlations (rs = 0.79-0.99). The standard errors of the estimate for %BF ranged from 3.5-4.6% and total errors for %BF ranged from 3.6-4.6%. The Slaughter equation using tricep and calf SKF for females was significantly different (P < 0.05) from the criterion measure in its prediction of %BF. In males, there was an interaction between the SKF equation and subject maturation level. The data indicate that the Slaughter SKF equations hold promise for estimating body composition in children and adolescents but are still in need of refinement.

The need for accurate assessment of minimal wrestling weight among interscholastic wrestlers has been well documented. Previous research has demonstrated the validity of anthropometric methods for this purpose, but little research has examined the validity of bioelectrical impedance (BIA) measurements. Comparisons between BIA systems has received limited attention. With these two objectives, we compared the prediction of minimal weight (MW) among 57 interscholastic wrestlers using three anthropometric methods (skinfolds (SF) and two skeletal dimensions equations) and three BIA systems (Berkeley Medical Research (BMR), RJL, and Valhalla (VAL]. All methods showed high correlations (r values greater than 0.92) with hydrostatic weighting (HW) and between methods (r values greater than 0.90). The standard errors of estimate (SEE) were relatively small for all methods, especially for SF and the three BIA systems (SEE less than 0.70 kg). The total errors of prediction (E) for RJL and VAL (E = 4.4 and 3.9 kg) were significantly larger than observed nonsignificant BMR and SF values (E = 2.3 and 1.8 kg, respectively). Significant mean differences were observed between HW, RJL, VAL, and the two skeletal dimensions equations, but nonsignificant differences were observed between HW, BMR, and SF. BMR differed significantly from the RJL and VAL systems. The results suggest that RJL and VAL have potential application for this subpopulation. Prediction equation refinement with the addition of selected anthropometric measurement or moderating variables may enhance their utility. However, within the scope of our study, SF and BMR BIA appear to be the most valid methods for determining MW in interscholastic wrestlers.