A Rhesus Monkey Model of Non-suicidal Self-Injury

Potential mechanisms of non-suicidal self-injury (NSSI) in major depressive disorder: a systematic review

Background

Non-suicidal self-injury (NSSI) is a frequent and prominent phenomenon in major depressive disorder (MDD). Even though its prevalence and risk factors are relatively well understood, the potential mechanisms of NSSI in MDD remain elusive.

Aims

To review present evidence related to the potential mechanisms of NSSI in MDD.

Methods

According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines, articles for this systematic review were searched on Medline (through PubMed), Embase (through Elsevier), PsycINFO (through OVID) and Web of Science databases for English articles, as well as China National Knowledge Infrastructure (CNKI), SinoMed, Wanfang Data, and the Chongqing VIP Chinese Science and Technology Periodical (VIP) Databases for Chinese articles published from the date of inception to 2 August 2022. Two researchers (BW, HZ) independently screened studies based on inclusion and exclusion criteria and assessed their quality.

Results

A total of 25 157 studies were searched. Only 25 of them were ultimately included, containing 3336 subjects (1535 patients with MDD and NSSI, 1403 patients with MDD without NSSI and 398 HCs). Included studies were divided into 6 categories: psychosocial factors (11 studies), neuroimaging (8 studies), stress and hypothalamic-pituitary-adrenal (HPA) axis (2 studies), pain perception (1 study), electroencephalogram (EEG) (2 studies) and epigenetics (1 study).

Conclusions

This systematic review indicates that patients with MDD and NSSI might have specific psychosocial factors, aberrant brain functions and neurochemical metabolisms, HPA axis dysfunctions, abnormal pain perceptions and epigenetic alterations.

Dermatologic Aspects of Zoo Mammal Medicine

The article deals with the primary aspects of how to maintain healthy integument in zoo mammals and in particular why husbandry-related health problems can occur in general in a zoologic setting. While working with these species we are often faced with diagnostic challenges, which may include a general approach (often requiring anesthesia or medical training), lack of "normal" references, and difficulties, especially if the cutaneous signs are not a primary ailment, but a manifestation of a generalized disease (eg, immune-suppression). The different etiologies of skin problems are discussed with clinical examples.

Key factors selection on adolescents with non-suicidal self-injury: A support vector machine based approach

Comparing a family structure to a company, one can often think of parents as leaders and adolescents as employees. Stressful family environments and anxiety levels, depression levels, personality disorders, emotional regulation difficulties, and childhood trauma may all contribute to non-suicidal self-injury (NSSI) behaviors. We presented a support vector machine (SVM) based method for discovering the key factors among mazy candidates that affected NSSI in adolescents. Using SVM as the base learner, and the binary dragonfly algorithm was used to find the feature combination that minimized the objective function, which took into account both the prediction error and the number of selected variables. Unlike univariate model analysis, we used a multivariate model to explore the risk factors, which better revealed the interactions between factors. Our research showed that adolescent education level, anxiety and depression level, borderline and avoidant personality traits, as well as emotional abuse and physical neglect in childhood, were associated with mood disorders in adolescents. Furthermore, gender, adolescent education level, physical abuse in childhood, non-acceptance of emotional responses, as well as paranoid, borderline, and histrionic personality traits, were associated with an increased risk of NSSI. These findings can help us make better use of artificial intelligence technology to extract potential factors leading to NSSI in adolescents from massive data, and provide theoretical support for the prevention and intervention of NSSI in adolescents.

Nonhuman primate abnormal behavior: Etiology, assessment, and treatment

Across captive settings, nonhuman primates may develop an array of abnormal behaviors including stereotypic and self-injurious behavior. Abnormal behavior can indicate a state of poor welfare, since it is often associated with a suboptimal environment. However, this may not always be the case as some behaviors can develop independently of any psychological distress, be triggered in environments known to promote welfare, and be part of an animal's coping mechanism. Furthermore, not all animals develop abnormal behavior, which has led researchers to assess risk factors that differentiate individuals in the display of these behaviors. Intrinsic risk factors that have been identified include the animal's species and genetics, age, sex, temperament, and clinical condition, while environmental risk factors include variables such as the animal's rearing, housing condition, husbandry procedures, and research experiences. To identify specific triggers and at-risk animals, the expression of abnormal behavior in captive nonhuman primates should be routinely addressed in a consistent manner by appropriately trained staff. Which behaviors to assess, what assessment methods to use, which primates to monitor, and the aims of data collection should all be identified before proceeding to an intervention and/or treatment. This article provides guidance for this process, by presenting an overview of known triggers and risk factors that should be considered, steps to design a comprehensive evaluation plan, and strategies that might be used for prevention or treatment. It also outlines the tools and processes for assessing and evaluating behavior in an appendix. This process will lead to a better understanding of abnormal behavior in captive primate colonies and ultimately to improved welfare.