Multivariate analysis of craniodental morphology in mouse-eared bats (Chiroptera, Vespertilionidae, Myotis) from Vietnam.

This study conducted biostatistical multivariate analyses on 23 craniodental morphological measurements from 209 specimens to study interspecific variations amongst 15 bat species of the genus Myotis in Vietnam. Univariate and multivariate analyses demonstrated that the studied species can be divided into four groups as follows: extra-large-sized species (M.chinensis), large-sized species (M.pilosus, M.indochinensis and M.annectans), medium-sized species (M.altarium, M.hasseltii, M.montivagus, M.horsfieldii, M.ater, M.laniger and M.muricola) and small-sized species (M.annamiticus, M.aff.siligorensis, M.rosseti and M.alticraniatus). Our data revealed that the main craniodental features contributing to the variations in distinguishing Myotis species are the width of the anterior palatal, least height of the coronoid process, length of the upper and lower canine-premolar, zygomatic width and width across the upper canines and lower premolar-molar length. Based on patterns of morphological differences, we conducted comparisons between morphometrically closely resembling species pairs and further discussed additional characteristics that are expected to support the taxonomy and systematics of Vietnamese Myotis bats.

Plant Cellulose as a Substrate for 3D Neural Stem Cell Culture.

Neural stem cell (NSC)-based therapies are at the forefront of regenerative medicine strategies for various neural defects and injuries such as stroke, traumatic brain injury, and spinal cord injury. For several clinical applications, NSC therapies require biocompatible scaffolds to support cell survival and to direct differentiation. Here, we investigate decellularized plant tissue as a novel scaffold for three-dimensional (3D), in vitro culture of NSCs. Plant cellulose scaffolds were shown to support the attachment and proliferation of adult rat hippocampal neural stem cells (NSCs). Further, NSCs differentiated on the cellulose scaffold had significant increases in their expression of neuron-specific beta-III tubulin and glial fibrillary acidic protein compared to 2D culture on a polystyrene plate, indicating that the scaffold may enhance the differentiation of NSCs towards astrocytic and neuronal lineages. Our findings suggest that plant-derived cellulose scaffolds have the potential to be used in neural tissue engineering and can be harnessed to direct the differentiation of NSCs.

Proceedings of the Third American Association of Oral and Maxillofacial Surgeons Anesthesia Patient Safety Conference.

The 3rd Anesthesia Patient Safety Conference of the American Association of Oral and Maxillofacial Surgeons was held at the Daniel M Laskin Institute for Oral and Maxillofacial Surgery Education and Innovation at American Association of Oral and Maxillofacial Surgeons headquarters in Rosemont, Illinois on June 6, 2022. The conference provided a platform to scrutinize collective errors, explore optimal practices, comprehend the concepts and principles of human complacency, assessing the system's capacity to handle deviations from the norm, and contemplate ideas and initiatives to enhance our practice model. These safety conferences are designed to foster collaborative, proactive conversations and understand best practices in safe delivery of anesthetic care to our patients.

Changes in synaptic inputs to dI3 INs and MNs after complete transection in adult mice.

Introduction: Spinal cord injury (SCI) is a debilitating condition that disrupts the communication between the brain and the spinal cord. Several studies have sought to determine how to revive dormant spinal circuits caudal to the lesion to restore movements in paralyzed patients. So far, recovery levels in human patients have been modest at best. In contrast, animal models of SCI exhibit more recovery of lost function. Previous work from our lab has identified dI3 interneurons as a spinal neuron population central to the recovery of locomotor function in spinalized mice. We seek to determine the changes in the circuitry of dI3 interneurons and motoneurons following SCI in adult mice. Methods: After a complete transection of the spinal cord at T9-T11 level in transgenic Isl1:YFP mice and subsequent treadmill training at various time points of recovery following surgery, we examined changes in three key circuits involving dI3 interneurons and motoneurons: (1) Sensory inputs from proprioceptive and cutaneous afferents, (2) Presynaptic inhibition of sensory inputs, and (3) Central excitatory glutamatergic synapses from spinal neurons onto dI3 INs and motoneurons. Furthermore, we examined the possible role of treadmill training on changes in synaptic connectivity to dI3 interneurons and motoneurons. Results: Our data suggests that VGLUT1+ inputs to dI3 interneurons decrease transiently or only at later stages after injury, whereas levels of VGLUT1+ remain the same for motoneurons after injury. Levels of VGLUT2+ inputs to dI3 INs and MNs may show transient increases but fall below levels seen in sham-operated mice after a period of time. Levels of presynaptic inhibition to VGLUT1+ inputs to dI3 INs and MNs can rise shortly after SCI, but those increases do not persist. However, levels of presynaptic inhibition to VGLUT1+ inputs never fell below levels observed in sham-operated mice. For some synaptic inputs studied, levels were higher in spinal cord-injured animals that received treadmill training, but these increases were observed only at some time points. Discussion: These results suggest remodeling of spinal circuits involving spinal interneurons that have previously been implicated in the recovery of locomotor function after spinal cord injury in mice.

SiliFish: A desktop application to model swimming behavior in developing zebrafish (Danio rerio).

SiliFish is an open-source desktop application to model and study zebrafish swimming. Here, we explain how to define the general parameters of the model, define cell populations, place them within the spinal cord, and define their projections. We explain how to run a simulation and how to visualize the network output and single-cell activity. The choice of C# as the programming language allows higher speed performance, simulating models with larger spinal circuits in less time. For complete details on the use and execution of this protocol, please refer to Roussel et al. (2021).1.

Comparison of the characteristics of patients treated with sublingual vs. long-acting injectable buprenorphine formulations for treatment of opioid use disorder: A retrospective cohort study.

OBJECTIVE: Long-acting injectable buprenorphine (LAI-BPN) was introduced in recent years as a novel treatment for opioid use disorder. Despite growing evidence-base of its effectiveness, there is limited research on the relationship between this treatment and patient characteristics. METHODS: This descriptive, retrospective cohort study compared sociodemographic and clinical variables between patients treated with SL-BPN and those treated with LAI-BPN at a large metropolitan health service in Queensland, Australia. RESULTS: Patients that transitioned to LAI-BPN were more likely to be single, have a comorbid mental illness, untreated hepatitis C infection and longer duration of unsanctioned opioid use. Patients continuing treatment with SL-BPN were more likely to fail to attend appointments and have urine drug screen results positive for gabapentinoids. CONCLUSIONS: The results of this study contribute to currently limited literature on this novel treatment option in an Australian context, highlighting factors which may influence patient and prescriber treatment choices. Clinicians may be more inclined to prescribe LAI-BPN to patients with higher psychosocial comorbidity to facilitate engagement in treatment.

The pathophysiology of major depressive disorder through the lens of systems biology: Network analysis of the psycho-immune-neuroendocrine physiome.

BACKGROUND/AIMS: The psycho-immune-neuroendocrine (PINE) network is a predominantly physiological (metabolomic) model constructed from the literature, inter-linking multiple biological processes associated with major depressive disorder (MDD), thereby integrating putative mechanistic pathways for MDD into a single network. MATERIAL AND METHODS: Previously published metabolomic pathways for the PINE network based on literature searches conducted in 1991-2021 were used to construct an edge table summarizing all physiological pathways in pairs of origin nodes and target nodes. The Gephi software program was used to calculate network metrics from the edge table, including total degree and centrality measures, to ascertain key network nodes and construct a directed network graph. RESULTS: An edge table and directional network graph of physiological relationships in the PINE network is presented. The network has properties consistent with complex biological systems, with analysis yielding key network nodes comprising pro-inflammatory cytokines (TNF- α, IL6 and IL1), glucocorticoids and corticotropin releasing hormone (CRH). These may represent central structural and regulatory elements in the context of MDD. CONCLUSION: The identified hubs have a high degree of connection and are known to play roles in the progression from health to MDD. These nodes represent strategic targets for therapeutic intervention or prevention. Future work is required to build a weighted and dynamic simulation of the network PINE.

Management of Posttraumatic Avascular Necrosis of the Proximal Humerus.

The etiology of avascular necrosis (AVN) of the proximal humerus can be classified as idiopathic or posttraumatic, the latter being mainly due to proximal humerus fractures. Evidence suggests that posttraumatic AVN may require surgical intervention more often than idiopathic AVN of the proximal humerus. This article provides a comprehensive review of the management of posttraumatic AVN of the proximal humerus. Early stage AVN (stages 1 to 3) is commonly treated with nonoperative intervention or core decompression of the humeral head, whereas later stage disease (stages 4 and 5) may require hemiarthroplasty or total shoulder arthroplasty to restore function. [Orthopedics. 2021;44(6):367-375.].

Stocktake of Australasian Psychiatry's training resources.

OBJECTIVE: To identify all past publications from Australasian Psychiatry with subject matter particularly relevant for trainees. The results of such a search could then be collated into an easily accessible resource available to trainees and their supervisors. METHOD: An electronic search of the journal's back catalogue was conducted. RESULTS: Eighty-seven articles published on subjects particularly relevant for trainees were discovered from within Australasian Psychiatry. In particular, multiple useful resources were identified on the topics of the scholarly project and formulation skills. CONCLUSIONS: Australasian Psychiatry has published a wealth of literature that is likely to be of significant benefit for trainees as they work their way through the Royal Australian and New Zealand College of Psychiatrists training programme.

Modeling spinal locomotor circuits for movements in developing zebrafish.

Many spinal circuits dedicated to locomotor control have been identified in the developing zebrafish. How these circuits operate together to generate the various swimming movements during development remains to be clarified. In this study, we iteratively built models of developing zebrafish spinal circuits coupled to simplified musculoskeletal models that reproduce coiling and swimming movements. The neurons of the models were based upon morphologically or genetically identified populations in the developing zebrafish spinal cord. We simulated intact spinal circuits as well as circuits with silenced neurons or altered synaptic transmission to better understand the role of specific spinal neurons. Analysis of firing patterns and phase relationships helped to identify possible mechanisms underlying the locomotor movements of developing zebrafish. Notably, our simulations demonstrated how the site and the operation of rhythm generation could transition between coiling and swimming. The simulations also underlined the importance of contralateral excitation to multiple tail beats. They allowed us to estimate the sensitivity of spinal locomotor networks to motor command amplitude, synaptic weights, length of ascending and descending axons, and firing behavior. These models will serve as valuable tools to test and further understand the operation of spinal circuits for locomotion.

The spinal cord is a column of nerve tissue that connects the brain to the rest of the body in vertebrate animals. Nerve cells in the spinal cord, called neurons, help to control and coordinate the body's movements. As the spinal cord develops, new neurons are born and new connections are made between neurons and muscles, resulting in more coordinated and skillful movements as time goes on. Zebrafish, for example, display body-bending maneuvers called coils within 24 hours of the egg being fertilized. Next, bursts of swimming movements emerge, which are driven by sporadic tail beats. These tail maneuvers become more consistent as the fish develops, and eventually result in smooth movements called beat-and-glide swimming. The groups of spinal cord neurons that appear at each stage of zebrafish development have been characterized, but it remains unclear how newly formed circuits (groups of neurons recently connected to each other) work together to produce swimming maneuvers. To answer this question, Roussel et al. simulated changes in the spinal cord that help zebrafish acquire new swimming movements as they grow. The computer models encoded neural circuits based on cell populations identified in experimental studies, and replicated swimming behaviors that emerge during the first few days of zebrafish development. Simulations tested how specific neural circuits generate the characteristic swimming movements that represent key developmental milestones in zebrafish. The results showed that adding new neurons and more cell-to-cell connections led to increasingly sophisticated swimming maneuvers. As the zebrafish spinal cord matured, the fish were better able to control the pace and duration of their swimming movements. Roussel et al. also identified specific patterns of neural activity linked to particular maneuvers. For example, tail beats switch direction when neurons on one side of the spinal cord excite neurons on the opposite side. This activity, which becomes more rhythmic, also needs to be exquisitely timed to produce and coordinate the right motion. Roussel et al.'s modelling of developmental milestones in growing zebrafish provides insights into how neural networks control movement. The computer models are among the first to accurately reproduce swimming behaviors in developing zebrafish. More experimental data could be added to the models to capture the full range of early zebrafish movements, and to further investigate how maturing spinal cord circuits control swimming. Since zebrafish and mammals have many spinal neurons in common, further research may aid our understanding of movement disorders in humans.

Updates in Management of Craniomaxillofacial Gunshot Wounds and Reconstruction of the Mandible.

This article includes updates in the management of mandibular trauma and reconstruction as they relate to maxillomandibular fixation screws, custom hardware, virtual surgical planning, and protocols for use of computer-aided surgery and navigation when managing composite defects from gunshot injuries to the face.

Spinal V1 neurons inhibit motor targets locally and sensory targets distally.

Rostro-caudal coordination of spinal motor output is essential for locomotion. Most spinal interneurons project axons longitudinally to govern locomotor output, yet their connectivity along this axis remains unclear. In this study, we use larval zebrafish to map synaptic outputs of a major inhibitory population, V1 (Eng1+) neurons, which are implicated in dual sensory and motor functions. We find that V1 neurons exhibit long axons extending rostrally and exclusively ipsilaterally for an average of 6 spinal segments; however, they do not connect uniformly with their post-synaptic targets along the entire length of their axon. Locally, V1 neurons inhibit motor neurons (both fast and slow) and other premotor targets, including V2a, V2b, and commissural premotor neurons. In contrast, V1 neurons make robust long-range inhibitory contacts onto a dorsal horn sensory population, the commissural primary ascending neurons (CoPAs). In a computational model of the ipsilateral spinal network, we show that this pattern of short-range V1 inhibition to motor and premotor neurons underlies burst termination, which is critical for coordinated rostro-caudal propagation of the locomotor wave. We conclude that spinal network architecture in the longitudinal axis can vary dramatically, with differentially targeted local and distal connections, yielding important consequences for function.

Changes in Sensorimotor Connectivity to dI3 Interneurons in Relation to the Postnatal Maturation of Grasping.

Primitive reflexes are evident shortly after birth. Many of these reflexes disappear during postnatal development as part of the maturation of motor control. This study investigates the changes of connectivity related to sensory integration by spinal dI3 interneurons during the time in which the palmar grasp reflex gradually disappears in postnatal mice pups. Our results reveal an increase in GAD65/67-labeled terminals to perisomatic Vglut1-labeled sensory inputs contacting cervical and lumbar dI3 interneurons between postnatal day 3 and day 25. In contrast, there were no changes in the number of perisomatic Vglut1-labeled sensory inputs to lumbar and cervical dI3 interneurons other than a decrease between postnatal day 15 and day 25. Changes in postsynaptic GAD65/67-labeled inputs to dI3 interneurons were inconsistent with a role in the sustained loss of the grasp reflex. These results suggest a possible link between the maturation of hand grasp during postnatal development and increased presynaptic inhibition of sensory inputs to dI3 interneurons.

Effects of Acute Experimental Stress on Pain Sensitivity and Cortisol Levels in Healthy Participants: A Randomized Crossover Pilot Study.

AIMS: To investigate pain sensitivity in the masseter muscle and index finger in response to acute psychologic stress in healthy participants. METHODS: Fifteen healthy women (23.7 ± 2.3 years) participated in two randomized sessions: in the experimental stress session, the Paced Auditory Serial Addition Task (PASAT) was used to induce acute stress, and in the control session, a control task was performed. Salivary cortisol, perceived stress levels, electrical and pressure pain thresholds (PTs), and pain tolerance levels (PTLs) were measured at baseline and after each task. Mixed-model analysis was used to test for significant interaction effects between time and session. RESULTS: An interaction effect between time and session occurred for perceived stress levels (P < .001); perceived stress was significantly higher after the experimental task than after the control task (P < .01). No interaction effects occurred for salivary cortisol levels, electrical PTs, or pressure PTLs. Although significant interactions did occur for electrical PTL (P < .05) and pressure PT (P < .001), the simple effects test could not identify significant differences between sessions at any time point. CONCLUSION: The PASAT evoked significant levels of perceived stress; however, pain sensitivity to mechanical or electrical stimuli was not significantly altered in response to the stress task, and the salivary cortisol levels were not altered in response to the PASAT. These results must be interpreted with caution, and more studies with larger study samples are needed to increase the clinical relevant understanding of the pain mechanisms and psychologic stress.

Spatiotemporal Transition in the Role of Synaptic Inhibition to the Tail Beat Rhythm of Developing Larval Zebrafish.

Significant maturation of swimming in zebrafish (Danio rerio) occurs within the first few days of life when fish transition from coiling movements to burst swimming and then to beat-and-glide swimming. This maturation occurs against a backdrop of numerous developmental changes - neurogenesis, a transition from predominantly electrical to chemical-based neurotransmission, and refinement of intrinsic properties. There is evidence that spinal locomotor circuits undergo fundamental changes as the zebrafish transitions from burst to beat-and-glide swimming. Our electrophysiological recordings confirm that the operation of spinal locomotor circuits becomes increasingly reliant on glycinergic neurotransmission for rhythmogenesis governing the rhythm of tail beats. This transition occurred at the same time that we observed a change in rhythmicity of synaptic inhibition to spinal motoneurons (MNs). When we examined whether the transition from weakly to strongly glycinergic dependent rhythmogenesis occurred at a uniform pace across the length of the spinal cord, we found that this transition occurred earlier at caudal segments than at rostral segments of the spinal cord. Furthermore, while this rhythmogenic transition occurred when fish transition from burst swimming to beat-and-glide swimming, these two transitions were not interdependent. These results suggest that there is a developmental transition in the operation of spinal locomotor circuits that is gradually set in place in the spinal cord in a caudo-rostral temporal sequence.

Propriospinal Neurons: Essential Elements of Locomotor Control in the Intact and Possibly the Injured Spinal Cord.

Propriospinal interneurons (INs) communicate information over short and long distances within the spinal cord. They act to coordinate different parts of the body by linking motor circuits that control muscles across the forelimbs, trunk, and hindlimbs. Their role in coordinating locomotor circuits near and far may be invaluable to the recovery of locomotor function lost due to injury to the spinal cord where the flow of motor commands from the brain and brainstem to spinal motor circuits is disrupted. The formation and activation of circuits established by spared propriospinal INs may promote the re-emergence of locomotion. In light of progress made in animal models of spinal cord injury (SCI) and in human patients, we discuss the role of propriospinal INs in the intact spinal cord and describe recent studies investigating the assembly and/or activation of propriospinal circuits to promote recovery of locomotion following SCI.

Unemployment and the rate of psychoactive-substance-related psychiatric hospital admission in regional Queensland: An observational, longitudinal study.

OBJECTIVES: To examine the relationship between a regional economic downturn (indicated by the rise of population unemployment rate) and the rate of psychoactive-substance-induced psychiatric hospital admissions in the population in a rural/regional setting. METHODS: Hospital admission records from January 2013 to December 2016 were reviewed retrospectively. All patients with admissions to the Mackay inpatient psychiatric unit with diagnosis of mental and behavioural disorders due to psychoactive substance use were recorded using (ICD-10) F10-F19 codes. The relationship between the regional unemployment rate and the hospital admission rate was analysed using linear regression analysis. RESULTS: A statistically significant regression was found (F(1,46) = 39.46, p < 0.0001), R2 = 0.46). The predicted number of admissions per 100,000 population in a month was observed to increase on average by 3.13 per month (95% CI = 2.12-4.13, p < 0.0001) for each percentage increase in the regional unemployment rate. CONCLUSIONS: There was a statistically significant association between the population unemployment rate and the rate of substance induced psychiatric hospital admissions. Implications for regional Australian service provision and unmet needs were discussed. Further research is required to confirm this observation.