Modifications of social conflict-induced analgesic and activity responses in male mice receiving chronic opioid agonist and antagonist treatments

Novel RNA N6-methyladenosine regulator related signature for predicting clinical and immunological characteristics in breast cancer

BACKGROUND

Epigenetic mechanismshave been reported to involve in shaping tumor immune microenvironment (TME). However, the role of RNA N6-methyladenosine (m6A) modification in breast cancerhas not been fully explored.

METHODS

Based on m6A modification and TME infiltration characteristics of 2249 breast cancer patients, we comprehensively correlated m6A modification with immune landscapeby screeningcandidate genes, function analysis and constructing m6Asignatures. Principal component analysis was used to establish the m6Ascore. Both LASSO and Cox regression analyses were used to evaluate its prognostic value.Functional assays and immunohistochemistry were used to evaluate the expression of m6A regulators and immune cell infiltration.

RESULTS

Based on the dysregulated expression of m6A, three distinct clusters were identified that displayed diverse types of tumour-associated TME cell infiltration in breast cancer.Gene signatures, stromal activity, and clinical prognosis were assessed by the m6Ascore. m6Ascore could function as a biomarker for predicting the therapeutic response to targeted therapy and immunotherapy.The dysregulated expression of m6Aregulators mediated the immune cell infiltration in the TME.

CONCLUSION

Basedonthestudy,weidentified the signature and potential mechanism of m6AmodificationsthatmodifyTME cell infiltration. Thus, targeting m6A regulators may provide a promisingmethodoftreatingBRCA.

Behavioral and neuronal attributes of short- and long-term habituation in the crab Chasmagnathus

Investigations using invertebrate species have led to a considerable progress in our understanding of the mechanisms underlying learning and memory. In this review we describe the main behavioral and neuronal findings obtained by studying the habituation of the escape response to a visual danger stimulus in the crab Chasmagnathus granulatus. Massed training with brief intertrial intervals lead to a rapid reduction of the escape response that recovers after a short term. Conversely, few trials of spaced training renders a slower escape reduction that endures for many days. As predicted by Wagner's associative theory of habituation, long-term habituation in the crab proved to be determined by an association between the contextual environment of the training and the unconditioned stimulus. By performing intracellular recordings in the brain of the intact animal at the same time it was learning, we identified a group of neurons that remarkably reflects the short- and long-term behavioral changes. Thus, the visual memory abilities of crabs, their relatively simple and accessible nervous system, and the recording stability that can be achieved with their neurons provide an opportunity for uncovering neurophysiological and molecular events that occur in identifiable neurons during learning.

Sex differences in naloxone- and Tyr-MIF-1-induced hypoalgesia

Reproductive adult male and female deer mice that received daily (7 days) injections of either the prototypic exogenous opiate antagonist, naloxone (1.0 mg/kg), or the endogenous putative antiopioid tetrapeptide, Tyr-MIF-1 (Tyr-Pro-Leu-Gly amide; 1.0 and 10 mg/kg), followed by determinations of thermal nociceptive sensitivity (hot-plate response) developed hypoalgesia. There were significant sex differences in this opioid blockade-induced or associated analgesia, with male mice displaying significantly greater hypoalgesia than females. Mice that received daily injections of either naloxone or Tyr-MIF-1 for 7 days without any accompanying determinations of nociceptive sensitivity (days 2-6 of treatment) failed to show any hypoalgesia on day 7 when they received the antagonist followed by a measurement of nociception. These results indicate that there are sex differences in both naloxone- and Tyr-MIF-1-induced hypoalgesia, and suggest that this pattern may be associated with sexually dimorphic opioid modulation of aversive conditioning.

Endogenous opiates: 1991

This paper is the fourteenth installment of our annual review of research concerning the opiate system. It includes papers published during 1991 involving the behavioral, nonanalgesic, effects of the endogenous opiate peptides. The specific topics this year include stress; tolerance and dependence; eating; drinking; gastrointestinal and renal function; mental illness and mood; learning, memory, and reward; cardiovascular responses; respiration and thermoregulation; seizures and other neurological disorders; electrical-related activity; general activity and locomotion; sex, pregnancy, and development; immunological responses; and other behaviors.