Src dependency of the regulation of LTP by alternative splicing of GRIN1 exon 5.

Alternative splicing of Grin1 exon 5 regulates induction of long-term potentiation (LTP) at Schaffer collateral-CA1 synapses: LTP in mice lacking the GluN1 exon 5-encoded N1 cassette (GluN1a mice) is significantly increased compared with that in mice compulsorily expressing this exon (GluN1b mice). The mechanism underlying this difference is unknown. Here, we report that blocking the non-receptor tyrosine kinase Src prevents induction of LTP in GluN1a mice but not in GluN1b. We find that activating Src enhances pharmacologically isolated synaptic N-methyl-d-aspartate receptor (NMDAR) currents in GluN1a mice but not in GluN1b. Moreover, we observe that Src activation increases the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor component of Schaffer collateral-evoked excitatory post-synaptic potentials in GluN1a mice, but this increase is prevented by blocking NMDARs. We conclude that at these synapses, NMDARs in GluN1a mice are subject to upregulation by Src that mediates induction of LTP, whereas NMDARs in GluN1b mice are not regulated by Src, leading to Src-resistance of LTP. Thus, we have uncovered that a key regulatory mechanism for synaptic potentiation is gated by differential splicing of exon 5 of Grin1. This article is part of a discussion meeting issue 'Long-term potentiation: 50 years on'.

A Cas9-fusion proximity-based approach generates an Irak1-Mecp2 tandem duplication mouse model for the study of MeCP2 duplication syndrome.

MECP2 duplication syndrome (MDS) is a neurodevelopmental disorder caused by tandem duplication of the MECP2 locus and its surrounding genes, including IRAK1. Current MDS mouse models involve transgenic expression of MECP2 only, limiting their applicability to the study of the disease. Herein, we show that an efficient and precise CRISPR/Cas9 fusion proximity-based approach can be utilized to generate an Irak1-Mecp2 tandem duplication mouse model ("Mecp2 Dup"). The Mecp2 Dup mouse model recapitulates the genomic landscape of human MDS by harbouring a 160 kb tandem duplication encompassing Mecp2 and Irak1, representing the minimal disease-causing duplication, and the neighbouring genes Opnmw1 and Tex28. The Mecp2 Dup model exhibits neuro-behavioral abnormalities, and an abnormal immune response to infection not previously observed in other mouse models, possibly owing to Irak1 overexpression. The Mecp2 Dup model thus provides a tool to investigate MDS disease mechanisms and develop potential therapies applicable to patients.

"Holding the badness": Therapists' experiences of treating incestuous abuse continuing into adulthood.

OBJECTIVE: This study aimed to explore the experience of therapists whose clients report incestuous abuse continuing into adulthood. METHOD: Ten Australian therapist-participants were recruited through professional forums. After giving informed consent, they completed a semistructured interview. Therapists were asked about their experiences of providing therapy to people who disclosed incestuous abuse that continued into adulthood and their experiences of training, peer support, and supervision in relation to these cases. The interviews were recorded, transcribed, labeled with a pseudonym, and deidentified. The transcripts were subjected to reflexive thematic analysis (TA) following the guidelines of Braun and Clarke (2006, 2022). RESULTS: The study found that three overarching themes described the therapeutic experience and response to this client group: (1) the therapist's emotional distress, vicarious traumatization, and moral injury at the extent of abuse and suffering disclosed by the client; (2) the need to adjust therapeutic goals and their reactions to this; and (3) feelings of professional isolation and a lack of support within mainstream services. CONCLUSIONS: The study describes therapeutic experience of a sample of practitioners and concludes that this work is distressing and demanding, requiring therapists to find their own coping methods, training, and supervision. The study points to needs for changes in practitioner training, service delivery, and policy to enable more holistic care of clients reporting complex ongoing abuse. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Pain hypersensitivity is dependent on autophagy protein Beclin 1 in males but not females.

Chronic pain is associated with alterations in fundamental cellular processes. Here, we investigate whether Beclin 1, a protein essential for initiating the cellular process of autophagy, is involved in pain processing and is targetable for pain relief. We find that monoallelic deletion of Becn1 increases inflammation-induced mechanical hypersensitivity in male mice. However, in females, loss of Becn1 does not affect inflammation-induced mechanical hypersensitivity. In males, intrathecal delivery of a Beclin 1 activator, tat-beclin 1, reverses inflammation- and nerve injury-induced mechanical hypersensitivity and prevents mechanical hypersensitivity induced by brain-derived neurotrophic factor (BDNF), a mediator of inflammatory and neuropathic pain. Pain signaling pathways converge on the enhancement of N-methyl-D-aspartate receptors (NMDARs) in spinal dorsal horn neurons. The loss of Becn1 upregulates synaptic NMDAR-mediated currents in dorsal horn neurons from males but not females. We conclude that inhibition of Beclin 1 in the dorsal horn is critical in mediating inflammatory and neuropathic pain signaling pathways in males.

Incestuous Abuse Continuing into Adulthood: Clinical Features and Therapists' Conceptualisations.

Prolonged incest, where children are sexually abused by familial perpetrators into adulthood, has been documented in clinical and criminological scholarship, however it is often overlooked in research, policy and practice approaches to familial sexual abuse. This article draws on interviews with ten Australian therapists about their clinical work with clients subject to incestuous abuse continuing into adulthood. It outlines their descriptions of these cases, the nature of the reported abuse and factors that facilitated prolonged and ongoing incest, including at the time of therapy. The therapists and their clients were female. The clients were highly dissociative and experienced significant psychiatric and medical comorbidity, and extensive socio-economic disadvantage. Reported abuse was sadistic, ongoing, often involved multiple perpetrators, and sometimes had links to organized abuse. Therapists' conceptualizations of the factors related to the abuse included: enmeshed and disorganized attachment to the perpetrator; symptoms of severe dissociation; having absent, abusive or non-protective mothers; and social isolation which limited help-seeking. The study concludes that attachment, trauma and dissociation-informed therapy is essential, while further research is needed to further explore effective interventions and responses to this clinical cohort.

Blocking Src-PSD-95 interaction rescues glutamatergic signaling dysregulation in schizophrenia.

The complex and heterogeneous genetic architecture of schizophrenia inspires us to look beyond individual risk genes for therapeutic strategies and target their interactive dynamics and convergence. Postsynaptic NMDA receptor (NMDAR) complexes are a site of such convergence. Src kinase is a molecular hub of NMDAR function, and its protein interaction subnetwork is enriched for risk-genes and altered protein associations in schizophrenia. Previously, Src activity was found to be decreased in post-mortem studies of schizophrenia, contributing to NMDAR hypofunction. PSD-95 suppresses Src via interacting with its SH2 domain. Here, we devised a strategy to suppress the inhibition of Src by PSD-95 via employing a cell penetrating and Src activating PSD-95 inhibitory peptide (TAT-SAPIP). TAT-SAPIP selectively increased post-synaptic Src activity in humans and mice, and enhanced synaptic NMDAR currents in mice. Chronic ICV injection of TAT-SAPIP rescued deficits in trace fear conditioning in Src hypomorphic mice. We propose blockade of the Src-PSD-95 interaction as a proof of concept for the use of interfering peptides as a therapeutic strategy to reverse NMDAR hypofunction in schizophrenia and other illnesses.

Broad host range phages target global Clostridium perfringens bacterial strains and clear infection in five-strain model systems.

Clostridium perfringens is a prevalent bacterial pathogen in poultry, and due to the spread of antimicrobial resistance, alternative treatments are needed to prevent and treat infection. Bacteriophages (phages), viruses that kill bacteria, offer a viable option and can be used therapeutically to treat C. perfringens infections. The aim of this study was to isolate phages against C. perfringens strains currently circulating on farms across the world and establish their virulence and development potential using host range screening, virulence assays, and larva infection studies. We isolated 32 phages of which 19 lysed 80%-92% of our global C. perfringens poultry strain collection (n = 97). The virulence of these individual phages and 32 different phage combinations was quantified in liquid culture at multiple doses. We then developed a multi-strain C. perfringens larva infection model, to mimic an effective poultry model used by the industry. We tested the efficacy of 16/32 phage cocktails in the larva model. From this, we identified that our phage cocktail consisting of phages CPLM2, CPLM15, and CPLS41 was the most effective at reducing C. perfringens colonization in infected larvae when administered before bacterial challenge. These data suggest that phages do have significant potential to prevent and treat C. perfringens infection in poultry. IMPORTANCE: Clostridium perfringens causes foodborne illness worldwide, and 95% of human infections are linked to the consumption of contaminated meat, including chicken products. In poultry, C. perfringens infection causes necrotic enteritis, and associated mortality rates can be up to 50%. However, treating infections is difficult as the bacterium is becoming antibiotic-resistant. Furthermore, the poultry industry is striving toward reduced antibiotic usage. Bacteriophages (phages) offer a promising alternative, and to progress this approach, robust suitable phages and laboratory models that mimic C. perfringens infections in poultry are required. In our study, we isolated phages targeting C. perfringens and found that many lyse C. perfringens strains isolated from chickens worldwide. Consistent with other published studies, in the model systems we assayed here, when some phages were combined as cocktails, the infection was cleared most effectively compared to individual phage use.

Calcium-Dependent Hyperexcitability in Human Stem Cell-Derived Rett Syndrome Neuronal Networks.

Background: Mutations in MECP2 predominantly cause Rett syndrome and can be modeled in vitro using human stem cell-derived neurons. Patients with Rett syndrome have signs of cortical hyperexcitability, such as seizures. Human stem cell-derived MECP2 null excitatory neurons have smaller soma size and reduced synaptic connectivity but are also hyperexcitable due to higher input resistance. Paradoxically, networks of MECP2 null neurons show a decrease in the frequency of network bursts consistent with a hypoconnectivity phenotype. Here, we examine this issue. Methods: We reanalyzed multielectrode array data from 3 isogenic MECP2 cell line pairs recorded over 6 weeks (n = 144). We used a custom burst detection algorithm to analyze network events and isolated a phenomenon that we termed reverberating super bursts (RSBs). To probe potential mechanisms of RSBs, we conducted pharmacological manipulations using bicuculline, EGTA-AM, and DMSO on 1 cell line (n = 34). Results: RSBs, often misidentified as single long-duration bursts, consisted of a large-amplitude initial burst followed by several high-frequency, low-amplitude minibursts. Our analysis revealed that MECP2 null networks exhibited increased frequency of RSBs, which produced increased bursts compared with isogenic controls. Bicuculline or DMSO treatment did not affect RSBs. EGTA-AM selectively eliminated RSBs and rescued network burst dynamics. Conclusions: During early development, MECP2 null neurons are hyperexcitable and produce hyperexcitable networks. This may predispose them to the emergence of hypersynchronic states that potentially translate into seizures. Network hyperexcitability depends on asynchronous neurotransmitter release that is likely driven by presynaptic Ca2+ and can be rescued by EGTA-AM to restore typical network dynamics.

"You Feel Like You Did Something So Wrong": Women's Experiences of a Loved One's Child Sexual Abuse Material Offending.

This article examines the experiences of female partners and relatives of child sexual abuse material offenders and the (il)legibility of their experiences within prevailing theoretical frameworks and policy responses to violence against women. Drawing on survey and interview data with clients of a specialist support agency, we situate the lack of understanding and support available to these women within the systematic depoliticization of child sexual abuse. The article traces how women developed their own social critique of child sexual exploitation as a form of gendered violence and called for a feminist reengagement with the politics of child sexual abuse.

The sexual politics of technology industry responses to online child sexual exploitation during COVID-19: "This pernicious elitism".

BACKGROUND: Increasing rates of online child sexual exploitation further spiked during the COVID-19 pandemic at a time of disrupted child protection capacity. While the technology industry is central to coordinated efforts to prevent online abuse and remove harmful content, it is largely exempt from formal child protection obligations. OBJECTIVE: The aim of this study was to examine the response of the technology industry to online child sexual exploitation during COVID-19 from the perspective of anti-exploitation professionals. PARTICIPANTS AND SETTING: An international sample of fifteen anti-exploitation professionals were interviewed as part of a larger study on the impacts of COVID-19 on online child sexual exploitation. METHODS: Interviews were coded based on a template analysis with a focus on interactions with the technology sector during COVID-19. RESULTS: Major themes arising from the analysis were 1) the burden of online safety work on victims and services, 2) the lack of prioritisation of online child protection by technology companies during COVID-19 and 3) the complicity of the technology industry with the online sexploitation of children. CONCLUSIONS: The analysis of the views of anti-exploitation professionals highlights the alignment between the economic interests of the technology sector and the sexual interests of online child abusers in the absence of government oversight. A framework of sexual politics highlights the gendered nature this alignment and emphasises the need for regulatory intervention, harm minimisation and the restructuring of the online environment and technology sector in the interests of child safety.

Parental Production of Child Sexual Abuse Material: A Critical Review.

The aim of this review is to summarize the available empirical research on parental production and to explore the discursive positioning of parental perpetrators within scholarship on child sexual abuse material (CSAM). Academic databases were searched using a combination of relevant terms, and the review was expanded as new terms were identified. The review identified 66 scholarly articles, papers, or books that referred to parental production of CSAM published since 1970. To explore how parental offenders have been positioned within this literature over time, the review is presented according to a chronological summary, drawing out key themes and empirical insights. The review showed that parental CSAM production is common, more likely to involve pre-pubescent victims, more severe abuse, female as well as male perpetrators, and produces high-demand illegal content with serious long-term sequelae. However, the review found that the focus of child trafficking and sexual exploitation scholarship on "commercial" and profit-driven abuse has marginalized and obscured parental CSAM production as a serious policy challenge. These findings warrant a reorientation of research, policy, and practice approaches to technology-facilitated child sexual exploitation, as well as a reflection on the resistance of researchers and policymakers to acknowledging the problem of family-based sexual exploitation.

Synapse-specific diversity of distinct postsynaptic GluN2 subtypes defines transmission strength in spinal lamina I.

The unitary postsynaptic response to presynaptic quantal glutamate release is the fundamental basis of excitatory information transfer between neurons. The view, however, of individual glutamatergic synaptic connections in a population as homogenous, fixed-strength units of neural communication is becoming increasingly scrutinized. Here, we used minimal stimulation of individual glutamatergic afferent axons to evoke single synapse resolution postsynaptic responses from central sensory lamina I neurons in an ex vivo adult rat spinal slice preparation. We detected unitary events exhibiting a NMDA receptor component with distinct kinetic properties across synapses conferred by specific GluN2 subunit composition, indicative of GluN2 subtype-based postsynaptic heterogeneity. GluN2A, 2A and 2B, or 2B and 2D synaptic predominance functioned on distinct lamina I neuron types to narrowly, intermediately, or widely tune, respectively, the duration of evoked unitary depolarization events from resting membrane potential, which enabled individual synapses to grade differentially depolarizing steps during temporally patterned afferent input. Our results lead to a model wherein a core locus of proteomic complexity prevails at this central glutamatergic sensory synapse that involves distinct GluN2 subtype configurations. These findings have major implications for subthreshold integrative capacity and transmission strength in spinal lamina I and other CNS regions.

Conserved transcriptional programming across sex and species after peripheral nerve injury predicts treatments for neuropathic pain.

BACKGROUND AND PURPOSE: Chronic pain is a devastating problem affecting one in five individuals around the globe, with neuropathic pain the most debilitating and poorly treated type of chronic pain. Advances in transcriptomics have contributed to cataloguing diverse cellular pathways and transcriptomic alterations in response to peripheral nerve injury but have focused on phenomenology and classifying transcriptomic responses. EXPERIMENTAL APPROACH: To identifying new types of pain-relieving agents, we compared transcriptional reprogramming changes in the dorsal spinal cord after peripheral nerve injury cross-sex and cross-species, and imputed commonalities, as well as differences in cellular pathways and gene regulation. KEY RESULTS: We identified 93 transcripts in the dorsal horn that were increased by peripheral nerve injury in male and female mice and rats. Following gene ontology and transcription factor analyses, we constructed a pain interactome for the proteins encoded by the differentially expressed genes, discovering new, conserved signalling nodes. We investigated the interactome with the Drug-Gene database to predict FDA-approved medications that may modulate key nodes within the network. The top hit from the analysis was fostamatinib, the molecular target of which is the non-receptor spleen associated tyrosine kinase (Syk), which our analysis had identified as a key node in the interactome. We found that intrathecally administrating the active metabolite of fostamatinib, R406 and another Syk inhibitor P505-15, significantly reversed pain hypersensitivity in both sexes. CONCLUSIONS AND IMPLICATIONS: Thus, we have identified and shown the efficacy of an agent that could not have been previously predicted to have analgesic properties.

A bacteriophage cocktail delivered in feed significantly reduced Salmonella colonization in challenged broiler chickens.

Nontyphoidal Salmonella spp. are a leading cause of human gastrointestinal infections and are commonly transmitted via the consumption of contaminated meat. To limit the spread of Salmonella and other food-borne pathogens in the food chain, bacteriophage (phage) therapy could be used during rearing or pre-harvest stages of animal production. This study was conducted to determine if a phage cocktail delivered in feed is capable of reducing Salmonella colonization in experimentally challenged chickens and to determine the optimal phage dose. A total of 672 broilers were divided into six treatment groups T1 (no phage diet and unchallenged); T2 (phage diet 106 PFU/day); T3 (challenged group); T4 (phage diet 105 PFU/day and challenged); T5 (phage diet 106 PFU/day and challenged); and T6 (phage diet 107 PFU/day and challenged). The liquid phage cocktail was added to mash diet with ad libitum access available throughout the study. By day 42 (the concluding day of the study), no Salmonella was detected in faecal samples collected from group T4. Salmonella was isolated from a small number of pens in groups T5 (3/16) and T6 (2/16) at ∼4 × 102 CFU/g. In comparison, Salmonella was isolated from 7/16 pens in T3 at ∼3 × 104 CFU/g. Phage treatment at all three doses had a positive impact on growth performance in challenged birds with increased weight gains in comparison to challenged birds with no phage diet. We showed delivering phages via feed was effective at reducing Salmonella colonization in chickens and our study highlights phages offer a promising tool to target bacterial infections in poultry.

Temperature, species identity and morphological traits predict carbonate excretion and mineralogy in tropical reef fishes.

Anthropogenic pressures are restructuring coral reefs globally. Sound predictions of the expected changes in key reef functions require adequate knowledge of their drivers. Here we investigate the determinants of a poorly-studied yet relevant biogeochemical function sustained by marine bony fishes: the excretion of intestinal carbonates. Compiling carbonate excretion rates and mineralogical composition from 382 individual coral reef fishes (85 species and 35 families), we identify the environmental factors and fish traits that predict them. We find that body mass and relative intestinal length (RIL) are the strongest predictors of carbonate excretion. Larger fishes and those with longer intestines excrete disproportionately less carbonate per unit mass than smaller fishes and those with shorter intestines. The mineralogical composition of excreted carbonates is highly conserved within families, but also controlled by RIL and temperature. These results fundamentally advance our understanding of the role of fishes in inorganic carbon cycling and how this contribution will change as community composition shifts under increasing anthropogenic pressures.

Regulation of neuropathic pain by microglial Orai1 channels.

Microglia are important mediators of neuroinflammation, which underlies neuropathic pain. However, the molecular checkpoints controlling microglial reactivity are not well-understood. Here, we investigated the role of Orai1 channels for microglia-mediated neuroinflammation following nerve injury and find that deletion of Orai1 in microglia attenuates Ca2+ signaling and the production of inflammatory cytokines by proalgesic agonists. Conditional deletion of Orai1 attenuated microglial proliferation in the dorsal horn, spinal cytokine levels, and potentiation of excitatory neurotransmission following peripheral nerve injury. These cellular effects were accompanied by mitigation of pain hyperalgesia in microglial Orai1 knockout mice. A small-molecule Orai1 inhibitor, CM4620, similarly mitigated allodynia in male mice. Unexpectedly, these protective effects were not seen in female mice, revealing sexual dimorphism in Orai1 regulation of microglial reactivity and hyperalgesia. Together, these findings indicate that Orai1 channels are key regulators of the sexually dimorphic role of microglia for the neuroinflammation that underlies neuropathic pain.

Neuropathic Pain: Mechanisms, Sex Differences, and Potential Therapies for a Global Problem.

The study of chronic pain continues to generate ever-increasing numbers of publications, but safe and efficacious treatments for chronic pain remain elusive. Recognition of sex-specific mechanisms underlying chronic pain has resulted in a surge of studies that include both sexes. A predominant focus has been on identifying sex differences, yet many newly identified cellular mechanisms and alterations in gene expression are conserved between the sexes. Here we review sex differences and similarities in cellular and molecular signals that drive the generation and resolution of neuropathic pain. The mix of differences and similarities reflects degeneracy in peripheral and central signaling processes by which neurons, immune cells, and glia codependently drive pain hypersensitivity. Recent findings identifying critical signaling nodes foreshadow the development of rationally designed, broadly applicable analgesic strategies. However, the paucity of effective, safe pain treatments compels targeted therapies as well to increase therapeutic options that help reduce the global burden of suffering.

"Living in the Darkness": Technology-Facilitated Coercive Control, Disenfranchised Grief, and Institutional Betrayal.

This article draws on interviews with 20 Australian women subjected to technology-facilitated coercive control (TFCC), foregrounding their accounts of grief and institutional betrayal. Findings show that while the harms of TFCC were significant, survivors' experiences were often minimized and dismissed by justice institutions. Women experienced grief due to abuse and separation from partners who had betrayed them. This loss was compounded when seeking help. We propose that disenfranchised grief is an underexplored response to domestic violence and institutional betrayal as well as a potential intervention site, particularly in relation to technology-facilitated abuse.

Wide spectrum of neuronal and network phenotypes in human stem cell-derived excitatory neurons with Rett syndrome-associated MECP2 mutations.

Rett syndrome (RTT) is a severe neurodevelopmental disorder primarily caused by heterozygous loss-of-function mutations in the X-linked gene MECP2 that is a global transcriptional regulator. Mutations in the methyl-CpG binding domain (MBD) of MECP2 disrupt its interaction with methylated DNA. Here, we investigate the effect of a novel MECP2 L124W missense mutation in the MBD of an atypical RTT patient with preserved speech in comparison to severe MECP2 null mutations. L124W protein had a limited ability to disrupt heterochromatic chromocenters due to decreased binding dynamics. We isolated two pairs of isogenic WT and L124W induced pluripotent stem cells. L124W induced excitatory neurons expressed stable protein, exhibited increased input resistance and decreased voltage-gated Na+ and K+ currents, and their neuronal dysmorphology was limited to decreased dendritic complexity. Three isogenic pairs of MECP2 null neurons had the expected more extreme morphological and electrophysiological phenotypes. We examined development and maturation of L124W and MECP2 null excitatory neural network activity using micro-electrode arrays. Relative to isogenic controls, L124W neurons had an increase in synchronous network burst frequency, in contrast to MECP2 null neurons that suffered a significant decrease in synchronous network burst frequency and a transient extension of network burst duration. A biologically motivated computational neural network model shows the observed changes in network dynamics are explained by changes in intrinsic Na+ and K+ currents in individual neurons. Our multilevel results demonstrate that RTT excitatory neurons show a wide spectrum of morphological, electrophysiological and circuitry phenotypes that are dependent on the severity of the MECP2 mutation.