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Substance use and antisocial behavior are complex, interrelated behaviors. The current study identified model trajectory classes defined by concurrent substance use and antisocial behavior and examined trajectory associations with emerging adult outcomes. Participants from a high-risk sample of youth (n=536; 73% male) completed interviews at baseline (mean age= 16.1 years) and followup (mean age= 22.6 years). Latent class growth analyses identified five trajectory classes based on alcohol/drug use (AOD) and antisocial behavior (ASB): Dual Chronic, Increasing AOD/Persistent ASB, Persistent AOD/Adolescent ASB, Decreasing Drugs/Persistent ASB, and Resolved. Many individuals (56%) exhibited elevated/increasing AOD, and most (91%) reported ASB decreases. Those associated with the Dual Chronic class had the highest rates of substance dependence, antisocial personality disorder (ASPD), and negative psychosocial outcomes. There were no differences in adult role attainment across classes. Conjoint examination of these behaviors provides greater detail regarding clinical course and can inform secondary prevention and intervention efforts.

Behavioral disinhibition (BD) is a quantitative measure designed to capture the heritable variation encompassing risky and impulsive behaviors. As a result, BD represents an ideal target for discovering genetic loci that predispose individuals to a wide range of antisocial behaviors and substance misuse that together represent a large cost to society as a whole. Published genome-wide association studies (GWAS) have examined specific phenotypes that fall under the umbrella of BD (e.g. alcohol dependence, conduct disorder); however no GWAS has specifically examined the overall BD construct. We conducted a GWAS of BD using a sample of 1,901 adolescents over-selected for characteristics that define high BD, such as substance and antisocial behavior problems, finding no individual locus that surpassed genome-wide significance. Although no single SNP was significantly associated with BD, restricted maximum likelihood analysis estimated that 49.3 % of the variance in BD within the Caucasian sub-sample was accounted for by the genotyped SNPs (p = 0.06). Gene-based tests identified seven genes associated with BD (p ≤ 2.0 × 10(-6)). Although the current study was unable to identify specific SNPs or pathways with replicable effects on BD, the substantial sample variance that could be explained by all genotyped SNPs suggests that larger studies could successfully identify common variants associated with BD.

Since DSM-IV was published in 1994, its approach to substance use disorders has come under scrutiny. Strengths were identified (notably, reliability and validity of dependence), but concerns have also arisen. The DSM-5 Substance-Related Disorders Work Group considered these issues and recommended revisions for DSM-5. General concerns included whether to retain the division into two main disorders (dependence and abuse), whether substance use disorder criteria should be added or removed, and whether an appropriate substance use disorder severity indicator could be identified. Specific issues included possible addition of withdrawal syndromes for several substances, alignment of nicotine criteria with those for other substances, addition of biomarkers, and inclusion of nonsubstance, behavioral addictions.This article presents the major issues and evidence considered by the work group, which included literature reviews and extensive new data analyses. The work group recommendations for DSM-5 revisions included combining abuse and dependence criteria into a single substance use disorder based on consistent findings from over 200,000 study participants, dropping legal problems and adding craving as criteria, adding cannabis and caffeine withdrawal syndromes, aligning tobacco use disorder criteria with other substance use disorders, and moving gambling disorders to the chapter formerly reserved for substance-related disorders. The proposed changes overcome many problems, while further studies will be needed to address issues for which less data were available.

The genes responsible for luminescence in various species of the marine microorganism "Photobacterium", have been used for many years as a tool by researchers and instructors. In particular, the "lux" operon of "Photobacterium fischeri" has been used by many instructors to teach recombinant DNA techniques. Two methods using an automated plate reader and multiwell plates were applied to a set of previously-published exercises. In these exercises that involve transfer of "lux" genes to "Escherichia coli" to create a luminescent phenotype, this technology was used to screen for Lux[superscript +] colonies. It was found to be more convenient and more sensitive than the previously used method; that is, assaying bacterial plates by direct observation. Eight students synthesized four genomic libraries and isolated six Lux[superscript +]clones. The fluorescent-detection feature of the plate reader was used to verify amplification of target sequence in polymerase chain reaction (PCR) reactions. Lux[superscript +] "E. coli" colony lysates were examined. An exonuclease-activated, fluorescent DNA probe generated a signal on hybridization to an amplified portion of the "lux"A gene in each lysate tested. This method is suggested as a means of demonstrating the concept of real-time PCR without the expense of the specialized device typically used for this technique. (Contains 3 tables, 1 footnote and 4 figures.)

In "Photobacterium," the flavin reductase encoded by "lux"G regenerates the reduced form of flavin mononucleotide (FMN). Reduced FMN is one of the substrates of the luciferase enzyme that catalyzes a light-emitting reaction. A set of experiments, that employs a "lux"G-expression plasmid construct (pGhis) and is suitable for an undergraduate laboratory course, is presented. Hexahistidine-tagged protein is expressed in "E. coli" from pGhis, with the T7 RNA polymerase/"lac" repressor induction system. Bacteria are lysed by sonication and the tag allows for purification by immobilized metal ion affinity chromatography. A gel filtration column is used to remove ions and the other small molecules. The Bradford assay, with multiwell plates and an automated plate reader, is used to identify protein concentration peaks from both columns. The concentration of purified enzyme is then calculated from its A[subscript 280] using the predicted extinction coefficient. Yield and purity are further assayed with SDS-PAGE. Activity of purified enzyme is measured with riboflavin or FMN as substrate. Reaction rate is quantified by monitoring decrease in A[subscript 340] as the redox partner, NADH, is oxidized. (Contains 7 figures and 6 tables.)

A study to examine the DSM-IV criteria for cannabis abuse and dependence among adolescents is conducted. Results conclude that abuse and dependence criteria were not found to affect the different levels of severity in cannabis use.

Objective: Adolescent patients' conduct disorder and substance use disorder symptoms are "risky behaviors" with unpredictable rewards and punishments. The authors asked whether such youths also take excessive risks in new situations without prior learning, peer pressure, or intoxication. Method: Subjects were 20 adolescent patients in a program treating conduct disorder and substance use disorder and 20 controls. All were substance free [greater than or equal to] 7 days; underwent substance-related, psychological, and social assessments; and performed the Balloon Analogue Risk Task: mouse presses inflated a computerized "balloon" image, each press earning 1 cent. The 30 balloons "popped" at unpredictable sizes; earnings from popped balloons were lost. A "Collect" response saved current earnings and advanced to the next balloon. Results: Mean number of inflating presses: patients, 1021 and controls, 705 (p = 0.001); group differences were stable from the task's beginning. Mean inflating presses before a "collect" response: patients, 38.6 and controls, 24.0 (p = 0.0005). Mean balloons popped: patients, 9.8 and controls, 6.3 (p = 0.001). Patients (versus controls) reported more aggressiveness and substance use and perceived less risk from substances. Patients' responses were significantly slower than those of controls. Conclusions: From the beginning of this novel task, conduct disorder and substance use disorder patients (compared with controls) took more risks, indicating an initial risk-taking propensity, although patients' slower responses argued against "impulsive, thoughtless" behavior. (Contains 3 figures and 1 table.)

Adolescents with substance use and conduct disorders have high rates of aggression and attention deficit hyperactivity disorder (ADHD), all of which have been characterized in part by impulsivity. Developing measures that capture impulsivity behaviorally and correlate with self-reported impulsivity has been difficult. One promising behavioral measure, however, is a variant of the continuous performance test, the Immediate Memory Test/Delayed Memory Test (IMT/DMT). The authors showed significant group differences between adolescents in treatment for serious substance and conduct problems and community controls on impulsivity measures, both behavioral and self-report, as well as on aggression and problem behavior measures. Furthermore, the IMT/DMT correlated significantly with self-reported impulsivity. In summary, the IMT/DMT may be an effective behavioral measure of impulsivity in adolescents. (Contains 6 tables and 2 figures.)

Responding to recent calls to rethink space, nature, and social difference outside of North American frameworks, this article draws on the anti-caste tradition in India to explore critiques of hierarchical "natures." It focuses on the thought of the towering anti-caste leader Dr. B. R. Ambedkar (1891–1956), who put forward an egalitarian critique of Brahmanical (upper caste) philosophy's emphasis on permanence and spatiotemporal fixity. The article situates Ambedkar's critique in the doubly colonial—British and Brahman—context in which he formulated his thought, and emphasizes Ambedkar's attempts to effect an epistemic break from Brahmanical conceptions of the world, including caste-based conceptions of space and nature. This critique, which is part of a broader tradition of anti-caste thought in western India, has received scant attention in international scholarship on nature and hierarchy. This tradition, the article argues, contains the seeds of an ecologically attuned anti-caste critique and can open new avenues for strengthening anti-caste/anti-racist solidarities. It particularly resonates with the works of Sylvia Wynter and those who have built on her insights about the struggle to define the human, and by extension, the nonhuman. This points toward egalitarian visions of ecology that break away from the fixity (or, more strongly, captivity) that characterizes hierarchical conceptions of nature. [ABSTRACT FROM AUTHOR]