International research teams analyzed several hundred thousand samples from 17 whole-exome sequencing studies to identify rare gene variants associated with smoking and alcohol use. They identified rare variants in 117 DNA regions as being associated with specific aspects of nicotine and alcohol use, including some in genes already known to influence these traits.
Rats with a disrupted transcription factor 7-like 2 (Tcf7l2) gene in the medial habenula showed markedly greater nicotine intake than control rats. Reduced Tcf7l2 expression in the medial habenula reduced the normally observed increase in blood sugar in response to nicotine.
Mice genetically engineered to lack mu opioid receptors in the medial habenula were less sensitive to the unpleasant effects of the opioid antagonist naloxone and showed fewer naloxone-induced withdrawal symptoms.
About 1 in 20 patients treated for a nonfatal opioid overdose in an emergency department died within 1 year of their visit, many within 2 days. Two-thirds of these deaths were directly attributed to subsequent opioid-related overdoses.
The degree of connectivity of a neuronal network in the rat brain before nicotine exposure can help predict nicotine dependence severity after nicotine exposure as well as reversal of dependence after a period of abstinence.
People’s decisions to use e-cigarettes, as well as perceptions about associated risks, are influenced by the e-cigarettes’ nicotine levels and available flavors. The influence of these characteristics on decision-making and perceived risk differs between people who smoke cigarettes and people who do not smoke.
This study found that HIV-1 could be eliminated in mice using a combination of two antiviral technologies—long-acting viral reservoir–targeted antiretroviral therapy and CRISPR/Cas-9 gene editing. HIV was undetectable in 9 out of 23 mice that received the combination treatment. HIV was not eliminated in any of the mice that were given either treatment alone.