Mucosal fungi promote gut barrier function and social behavior via Type 17 immunity.

Fungal communities (the mycobiota) are an integral part of the gut microbiota, and the disruption of their integrity contributes to local and gut-distal pathologies. Yet, the mechanisms by which intestinal fungi promote homeostasis remain unclear. We characterized the mycobiota biogeography along the gastrointestinal tract and identified a subset of fungi associated with the intestinal mucosa of mice and humans. Mucosa-associated fungi (MAF) reinforced intestinal epithelial function and protected mice against intestinal injury and bacterial infection. Notably, intestinal colonization with a defined consortium of MAF promoted social behavior in mice. The gut-local effects on barrier function were dependent on IL-22 production by CD4+ T helper cells, whereas the effects on social behavior were mediated through IL-17R-dependent signaling in neurons. Thus, the spatial organization of the gut mycobiota is associated with host-protective immunity and epithelial barrier function and might be a driver of the neuroimmune modulation of mouse behavior through complementary Type 17 immune mechanisms.

Astrocytes derived from ASD individuals alter behavior and destabilize neuronal activity through aberrant Ca2+ signaling.

The cellular mechanisms of autism spectrum disorder (ASD) are poorly understood. Cumulative evidence suggests that abnormal synapse function underlies many features of this disease. Astrocytes regulate several key neuronal processes, including the formation of synapses and the modulation of synaptic plasticity. Astrocyte abnormalities have also been identified in the postmortem brain tissue of ASD individuals. However, it remains unclear whether astrocyte pathology plays a mechanistic role in ASD, as opposed to a compensatory response. To address this, we combined stem cell culturing with transplantation techniques to determine disease-specific properties inherent to ASD astrocytes. We demonstrate that ASD astrocytes induce repetitive behavior as well as impair memory and long-term potentiation when transplanted into the healthy mouse brain. These in vivo phenotypes were accompanied by reduced neuronal network activity and spine density caused by ASD astrocytes in hippocampal neurons in vitro. Transplanted ASD astrocytes also exhibit exaggerated Ca2+ fluctuations in chimeric brains. Genetic modulation of evoked Ca2+ responses in ASD astrocytes modulates behavior and neuronal activity deficits. Thus, this study determines that astrocytes derived from ASD iPSCs are sufficient to induce repetitive behavior as well as cognitive deficit, suggesting a previously unrecognized primary role for astrocytes in ASD.

Academic anaesthesiology: a global perspective on training, support, and future development of early career researchers.

As anaesthesiologists face increasing clinical demands and a limited and competitive funding environment for academic work, the sustainability of academic anaesthesiologists has never been more tenuous. Yet, the speciality needs academic anaesthesiologists in many roles, extending beyond routine clinical duties. Anaesthesiologist educators, researchers, and administrators are required not only to train future generations but also to lead innovation and expansion of anaesthesiology and related specialities, all to improve patient care. This group of early career researchers with geographically distinct training and practice backgrounds aim to highlight the diversity in clinical and academic training and career development pathways for anaesthesiologists globally. Although multiple routes to success exist, one common thread is the need for consistent support of strong mentors and sponsors. Moreover, to address inequitable opportunities, we emphasise the need for diversity and inclusivity through global collaboration and exchange that aims to improve access to research training and participation. We are optimistic that by focusing on these fundamental principles, we can help build a more resilient and sustainable future for academic anaesthesiologists around the world.

How and what adverse events are reported and captured in randomized control trials of emollients in the treatment of eczema?

BACKGROUND: Emollients are universally recommended for atopic dermatitis/eczema ('eczema'), to improve the skin barrier and reduce symptoms. However, our knowledge of the frequency and nature of adverse effects associated with their use is limited. OBJECTIVES: We sought to determine how well adverse events are reported in randomized controlled trials (RCTs) of emollients for eczema. METHODS: MEDLINE was searched from inception (1946) to May 2022. Inclusion criteria were RCTs of moisturizers or emollients used as a leave-on treatment (as the intervention or control) in adults or children with eczema. Exclusion criteria were non-RCTs; patients with other diagnoses included; use of emollient as bath additives, soap substitutes or as preventative; and not published in English. References of eligible papers were reviewed for any additional, relevant research. Data were extracted into an Excel spreadsheet and analysed descriptively. An assessment of study quality was carried out using the Joanna Briggs Institute tool for RCTs. RESULTS: From 369 potential papers, 35 papers (reporting on 34 studies) were included. Most research was conducted in research centres or hospitals (unclear in 34%). In total, 89% reported collecting data on adverse events related to emollient treatment use but the methods used were poorly reported (40% unclear). Four papers used patient questionnaires/diaries. However, it was unclear how and what was collected as only two studies showed the questionnaires used. CONCLUSIONS: Reporting of adverse events related to emollient use in trials of patients with eczema is poor and inconsistent. Agreement should be reached on how and what adverse events should be collected, to standardize reporting across studies.

A Pilot Randomized Clinical Trial of Base-in Relieving Prism Spectacle Treatment of Intermittent Exotropia.

SIGNIFICANCE: This pilot randomized trial, the first to evaluate a specific base-in relieving prism treatment strategy for childhood intermittent exotropia, did not support proceeding to a full-scale clinical trial. Defining and measuring prism adaptation in children with intermittent exotropia are challenging and need further study. PURPOSE: This study aimed to determine whether to proceed to a full-scale trial of relieving base-in prism spectacles versus refractive correction alone for children with intermittent exotropia. METHODS: Children 3 years old to those younger than 13 years with distance intermittent exotropia control score of ≥2 points on the Intermittent Exotropia Office Control Scale (Strabismus 2006;14:147-150; 0 [phoria] to 5 [constant]), ≥1 episode of spontaneous exotropia, and 16 to 35∆ by prism-and-alternate-cover test, who did not fully prism adapt on a 30-minute in-office prism-adaptation test were randomized to base-in relieving prism (40% of the larger of distance and near exodeviations) or nonprism spectacles for 8 weeks. A priori criteria to conduct a full-scale trial were defined for the adjusted treatment group difference in mean distance control: "proceed" (≥0.75 points favoring prism), "uncertain" (>0 to <0.75 points favoring prism), or "do not proceed" (≥0 points favoring nonprism). RESULTS: Fifty-seven children (mean age, 6.6 ± 2.2 years; mean baseline distance control, 3.5 points) received prism (n = 28) or nonprism (n = 29) spectacles. At 8 weeks, mean control values were 3.6 and 3.3 points in prism (n = 25) and nonprism (n = 25) groups, respectively, with an adjusted difference of 0.3 points (95% confidence interval, -0.5 to 1.1 points) favoring nonprism (meeting our a priori "do not proceed" criterion). CONCLUSIONS: Base-in prism spectacles, equal to 40% of the larger of the exodeviations at distance or near, worn for 8 weeks by 3- to 12-year-old children with intermittent exotropia did not yield better distance control than refractive correction alone, with the confidence interval indicating that a favorable effect of 0.75 points or larger is unlikely. There was insufficient evidence to warrant a full-scale randomized trial.

Improper Restraint Use in Pediatric Patients Involved in Motor Vehicle Collisions.

BACKGROUND: Motor vehicle collisions (MVCs) are the leading cause of unintentional death among children and adolescents; however, public awareness and use of appropriate restraint recommendations are perceived as deficient. We aimed to investigate the use of child safety restraints and examine outcomes in our community. METHODS: We retrospectively queried a level 1 trauma registry for pediatric (0-18 y) MVC patients from October 2013 to December 2018. Demographic and clinical variables were recorded. Data regarding appropriate restraint use by age group were examined. RESULTS: Four hundred thirty-four cases of pediatric MVC were identified. Overall, 53% were improperly restrained or unrestrained. Sixty-two percent of car seat age and 51% of booster age children were improperly restrained or unrestrained altogether. Fifty-nine percent of back seat riding, seatbelt age were improperly restrained/unrestrained, with 26% riding in the front. Fifty-one percent of seatbelt-only adolescents were not belted. Black, non-Hispanic children were more often improperly restrained/unrestrained compared to Hispanics (63% versus 48%, P = 0.001). Improperly restrained/unrestrained children had higher injury severity (10% versus 4% Injury Severity Score > 25, P = 0.021), require operative/interventional radiology (33% versus 19%, P = 0.001), and be discharged to rehabilitation or skilled nursing facility (5.2% versus 1.5%, P = 0.033). Mortality in adolescents was higher among those unrestrained (5.2% versus 0.8%, P = 0.034). CONCLUSIONS: Although efforts to improve adherence to restraint regulations have greatly increased in the last decade, more than half of children in MVC are still improperly restrained. Injury prevention services and community outreach is essential to educate the most vulnerable populations, especially those with infants and toddlers, on adequate motor vehicle safety measures in our community.

UPF2 leads to degradation of dendritically targeted mRNAs to regulate synaptic plasticity and cognitive function.

Synaptic plasticity requires a tight control of mRNA levels in dendrites. RNA translation and degradation pathways have been recently linked to neurodevelopmental and neuropsychiatric diseases, suggesting a role for RNA regulation in synaptic plasticity and cognition. While the local translation of specific mRNAs has been implicated in synaptic plasticity, the tightly controlled mechanisms that regulate local quantity of specific mRNAs remain poorly understood. Despite being the only RNA regulatory pathway that is associated with multiple mental illnesses, the nonsense-mediated mRNA decay (NMD) pathway presents an unexplored regulatory mechanism for synaptic function and plasticity. Here, we show that neuron-specific disruption of UPF2, an NMD component, in adulthood attenuates learning, memory, spine density, synaptic plasticity (L-LTP), and potentiates perseverative/repetitive behavior in mice. We report that the NMD pathway operates within dendrites to regulate Glutamate Receptor 1 (GLUR1) surface levels. Specifically, UPF2 modulates the internalization of GLUR1 and promotes its local synthesis in dendrites. We identified neuronal Prkag3 mRNA as a mechanistic substrate for NMD that contributes to the UPF2-mediated regulation of GLUR1 by limiting total GLUR1 levels. These data establish that UPF2 regulates synaptic plasticity, cognition, and local protein synthesis in dendrites, providing fundamental insight into the neuron-specific function of NMD within the brain.

Disruption of perineuronal nets increases the frequency of sharp wave ripple events.

Hippocampal sharp wave ripples (SWRs) represent irregularly occurring synchronous neuronal population events that are observed during phases of rest and slow wave sleep. SWR activity that follows learning involves sequential replay of training-associated neuronal assemblies and is critical for systems level memory consolidation. SWRs are initiated by CA2 or CA3 pyramidal cells (PCs) and require initial excitation of CA1 PCs as well as participation of parvalbumin (PV) expressing fast spiking (FS) inhibitory interneurons. These interneurons are relatively unique in that they represent the major neuronal cell type known to be surrounded by perineuronal nets (PNNs), lattice like structures composed of a hyaluronin backbone that surround the cell soma and proximal dendrites. Though the function of the PNN is not completely understood, previous studies suggest it may serve to localize glutamatergic input to synaptic contacts and thus influence the activity of ensheathed cells. Noting that FS PV interneurons impact the activity of PCs thought to initiate SWRs, and that their activity is critical to ripple expression, we examine the effects of PNN integrity on SWR activity in the hippocampus. Extracellular recordings from the stratum radiatum of horizontal murine hippocampal hemisections demonstrate SWRs that occur spontaneously in CA1. As compared with vehicle, pre-treatment (120 min) of paired hemislices with hyaluronidase, which cleaves the hyaluronin backbone of the PNN, decreases PNN integrity and increases SWR frequency. Pre-treatment with chondroitinase, which cleaves PNN side chains, also increases SWR frequency. Together, these data contribute to an emerging appreciation of extracellular matrix as a regulator of neuronal plasticity and suggest that one function of mature perineuronal nets could be to modulate the frequency of SWR events.

p39 Is Responsible for Increasing Cdk5 Activity during Postnatal Neuron Differentiation and Governs Neuronal Network Formation and Epileptic Responses.

Two distinct protein cofactors, p35 and p39, independently activate Cyclin-dependent kinase 5 (Cdk5), which plays diverse roles in normal brain function and the pathogenesis of many neurological diseases. The initial discovery that loss of p35 impairs neuronal migration in the embryonic brain prompted intensive research exploring the function of p35-dependent Cdk5 activity. In contrast, p39 expression is restricted to the postnatal brain and its function remains poorly understood. Despite the robustly increased Cdk5 activity during neuronal differentiation, which activator is responsible for enhancing Cdk5 activation and how the two distinct activators direct Cdk5 signaling to govern neuronal network formation and function still remains elusive. Here we report that p39, but not p35, is selectively upregulated by histone acetylation-mediated transcription, which underlies the robust increase of Cdk5 activity during rat and mouse neuronal differentiation. The loss of p39 attenuates overall Cdk5 activity in neurons and preferentially affects phosphorylation of specific Cdk5 targets, leading to aberrant axonal growth and impaired dendritic spine and synapse formation. In adult mouse brains, p39 deficiency results in dysregulation of p35 and Cdk5 targets in synapses. Moreover, in contrast to the proepileptic phenotype caused by the lack of p35, p39 loss leads to deficits in maintaining seizure activity and induction of immediate early genes that control hippocampal excitability. Together, our studies demonstrate essential roles of p39 in neuronal network development and function. Furthermore, our data support a model in which Cdk5 activators play nonoverlapping and even opposing roles to govern balanced Cdk5 signaling in the postnatal brain. SIGNIFICANCE STATEMENT: Neuronal network development requires tightly regulated activation of Cyclin-dependent kinase 5 (Cdk5) by two distinct cofactors, p35 and p39. Despite the well-known p35-dependent Cdk5 function, why postnatal neurons express abundant p39 in addition to p35 remained unknown for decades. In this study, we discovered that selective upregulation of p39 is the underlying mechanism that accommodates the increased functional requirement of Cdk5 activation during neuronal differentiation. In addition, we demonstrated that p39 selectively directs Cdk5 to phosphorylate protein substrates essential for axonal development, dendritic spine formation, and synaptogenesis. Moreover, our studies suggest opposing roles of p39 and p35 in synaptic Cdk5 function and epileptic responses, arguing that cooperation between Cdk5 activators maintains balanced Cdk5 signing, which is crucial for postnatal brain function.

Safety of deep sedation in the endoscopy suite.

PURPOSE OF REVIEW: As the complexity of endoscopic procedures increases, the use of propofol and the desire for deep sedation are becoming more common in the endoscopy suite. This review explores sedation depth, agents used for sedation, recommended monitoring, and adverse event risks that occur during sedation for endoscopy. RECENT FINDINGS: The sedation provider for endoscopy varies by practice location and with regulatory requirements. As increasingly deep levels of sedation are used in this setting, the need for all providers to have training in the ability to rescue patients from sedation-related side effects is paramount. Propofol has an important role for prolonged and uncomfortable endoscopic interventions and has a strong safety record in the endoscopy suite. Vital signs monitoring is recommended during all endoscopy sedation, and there is emerging interest in advanced monitoring (e.g., capnography, processed electroencephalogram, respiratory monitoring) in this setting. The reported rate of adverse events during endoscopy sedation varies widely; however, advanced age and increasing American Society of Anesthesiologists physical status score are consistently associated with increased risk. Whether anesthesiologist-administered sedation is safer than non-anesthesiologist-administered sedation remains controversial. SUMMARY: This review provides some guidance to providers who administer sedation in the endoscopy suite and is intended to improve the safety of patients. The recommendations are based on best available evidence and expert opinion.

A randomized-controlled trial of high- or low-volume intravenous Plasma-Lyte(®) to prevent hypotension during sedation for colonoscopy.

PURPOSE: The purpose of this study was to compare the incidence of hypotension during sedation in adults presenting for elective colonoscopy and randomized to intravenous Plasma-Lyte 148(®) at either 2 mL·kg(-1) (low volume) or 20 mL·kg(-1) (high volume). METHODS: Patients aged ≥ 18 yr presenting for elective colonoscopy, with or without gastroscopy, after oral bowel preparation were randomized to receive the intervention immediately before the start of the procedure. Hypotension was defined as a ≥ 25% decrease in systolic blood pressure (SBP) from baseline during the procedure. Secondary outcomes included SBP < 90 mmHg, lowest SBP during sedation, duration of hypotension, use of vasopressors, postoperative outcomes, and cost. RESULTS: Seventy-five patients were randomly allocated to either the low-volume or high-volume group, respectively (total n = 150). The incidence of hypotension was similar in the two groups (59% vs 56%, respectively; odds ratio, 0.90; 95% confidence interval, 0.47 to 1.71; P = 0.74). The incidence of SBP < 90 mmHg, the lowest SBP during sedation, the duration of hypotension, the use of vasopressors, and postoperative outcomes were also similar in the two groups. CONCLUSIONS: This study does not support the routine use of 20 mL·kg(-1) of intravenous Plasma-Lyte 148 to prevent hypotension and other complications during sedation for elective colonoscopy in adult patients. Clinical Trials Registry (ANZCTR 12615001288516).

A randomized controlled trial of light versus deep propofol sedation for elective outpatient colonoscopy: recall, procedural conditions, and recovery.

PURPOSE: This study aimed to determine if the incidence of recall was equivalent between light and deep sedation for colonoscopy. Secondary analysis included complications, patient clinical recovery, and post-procedure cognitive impairment. METHODS: Two hundred patients undergoing elective outpatient colonoscopy were randomized to light (bispectral index [BIS] 70-80) or deep (BIS < 60) sedation with propofol and fentanyl. Recall was assessed by the modified Brice questionnaire, and cognition at baseline and discharge was assessed using a Cogstate test battery. RESULTS: The median (interquartile range [IQR]) BIS values were different in the two groups (69 [65-74] light sedation vs 53 [46-59] deep sedation; P < 0.0001). The incidence of recall was 12% in the light sedation group and 1% in the deep sedation group. The risk difference for recall was 0.11 (90% confidence interval, 0.05 to 0.17) in the intention-to-treat analysis, thus refuting equivalence in recall between light and deep sedation (0.05 significance level; 10% equivalence margin). Overall sedation-related complications were more frequent with deep sedation than with light sedation (66% vs 47%, respectively; P = 0.008). Recovery was more rapid with light sedation than with deep sedation as determined by the mean (SD) time to reach a score of 5 on the Modified Observer's Assessment of Alertness/Sedation Scale [3 (4) min vs 7 (4) min, respectively; P < 0.001] and by the median [IQR] time to readiness for hospital discharge (65 [57-80] min vs 74 [63-86] min, respectively; P = 0.001). The incidence of post-procedural cognitive impairment was similar in those randomized to light (19%) vs deep (16%) sedation (P = 0.554). CONCLUSION: Light sedation was not equivalent to deep sedation for procedural recall, the spectrum of complications, or recovery times. This study provides evidence to inform discussions with patients about sedation for colonoscopy. This trial was registered at the Australian and New Zealand Clinical Trials Registry, number 12611000320954.

Loss of CDKL5 disrupts kinome profile and event-related potentials leading to autistic-like phenotypes in mice.

Mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene have been identified in neurodevelopmental disorders including atypical Rett syndrome (RTT), autism spectrum disorders (ASDs), and early infantile epileptic encephalopathy. The biological function of CDKL5 and its role in the etiology of these disorders, however, remain unclear. Here we report the development of a unique knockout mouse model of CDKL5-related disorders and demonstrate that mice lacking CDKL5 show autistic-like deficits in social interaction, as well as impairments in motor control and fear memory. Neurophysiological recordings reveal alterations in event-related potentials (ERPs) similar to those observed in RTT and ASDs. Moreover, kinome profiling uncovers disruption of multiple signal transduction pathways, including the AKT-mammalian target of rapamycin (mTOR) cascade, upon Cdkl5 loss-of-function. These data demonstrate that CDKL5 regulates signal transduction pathways and mediates autistic-like phenotypes and together establish a causal role for Cdkl5 loss-of-function in neurodevelopmental disorders.

The MMP-1/PAR-1 Axis Enhances Proliferation and Neuronal Differentiation of Adult Hippocampal Neural Progenitor Cells.

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that play a role in varied forms of developmental and postnatal neuroplasticity. MMP substrates include protease-activated receptor-1 (PAR-1), a G-protein coupled receptor expressed in hippocampus. We examined proliferation and differentiation of adult neural progenitor cells (aNPCs) from hippocampi of mice that overexpress the potent PAR-1 agonist MMP-1. We found that, as compared to aNPCs from littermate controls, MMP-1 tg aNPCs display enhanced proliferation. Under differentiating conditions, these cells give rise to a higher percentage of MAP-2(+) neurons and a reduced number of oligodendrocyte precursors, and no change in the number of astrocytes. The fact that these results are MMP and PAR-1 dependent is supported by studies with distinct antagonists. Moreover, JSH-23, an inhibitor of NF-κB p65 nuclear translocation, counteracted both the proliferation and differentiation changes seen in MMP-1 tg-derived NPCs. In complementary studies, we found that the percentage of Sox2(+) undifferentiated progenitor cells is increased in hippocampi of MMP-1 tg animals, compared to wt mice. Together, these results add to a growing body of data suggesting that MMPs are effectors of hippocampal neuroplasticity in the adult CNS and that the MMP-1/PAR-1 axis may play a role in neurogenesis following physiological and/or pathological stimuli.

Pelvic Floor Disorders Among U.S. Military Active-Duty Females.

IMPORTANCE: Women are a growing cohort within the U.S. military. Pelvic floor health is a component of health maintenance for which support needs vary by sex. The American Journal of Obstetrics & Gynecology reports that 1 in 4 women is affected by moderate to severe pelvic floor dysfunction (PFD). Understanding the specific experience of female service members is warranted for health care optimization and preservation of force readiness. OBJECTIVE: We aimed to identify the prevalence, incidence, and risk factors associated with incident PFD in active-duty females during an 11-year window. STUDY DESIGN: We used the Medical Assessment and Readiness System at Womack Army Medical Center, which includes medical record and personnel data from 2011 to 2022. Pelvic floor dysfunction diagnoses were identified using diagnosis codes and analyzed with respect to demographic parameters. RESULTS: Between 2011 and 2022, 32,996 of 550,303 active-duty females were diagnosed with PFD (period prevalence: 6.00%). Using 2011-2012 as a washout period, 27,046 of 486,558 participants were diagnosed during 1,879,990.90 person-years of follow-up (incidence rate: 14.39 cases per 1,000 person-years). The incidence rate of PFD increased in both new and established active-duty females. Increasing time since service entry was the strongest, statistically significant independent predictor of PFD. Three or more deployments and specific physical fitness scoring were also predictors of PFD. CONCLUSIONS: The incidence rate of PFD among female service members is increasing, and multiple military-specific factors predict PFD. As the percentage of women in active-duty service continues to grow, additional investigation is needed to confirm PFD trends, illuminate other predictors, and prevent adverse outcomes.

Difluorinated thromboxane A2 reveals crosstalk between platelet activatory and inhibitory pathways by targeting both the TP and IP receptors.

BACKGROUND AND PURPOSE: Thromboxane A2 (TXA2) is a prostanoid produced during platelet activaton, important in enhancing platelet reactivity by activation of TP receptors. However, due to the short half-life, studying TXA2 signalling is challenging. To enhance our understanding of TP receptor-mediated platelet biology, we therefore synthesised mono and difluorinated TXA2 analogues and explored their pharmacology on heterologous and endogenously expressed TP receptor function. EXPERIMENTAL APPROACH: Platelet functional and signalling responses were studied using aggregometry, Ca2+ mobilisation experiments and immunoblotting and compared with an analogue of the TXA2 precursor prostaglandin H2, U46619. Gαq/Gαs receptor signalling was determined using a bioluminescence resonance energy transfer (BRET) assay in a cell line overexpression system. KEY RESULTS: BRET studies revealed that F-TXA2 and F2-TXA2 promoted receptor-stimulated TP receptor G-protein activation similarly to U46619. Unexpectedly, F2-TXA2 caused reversible aggregation in platelets, whereas F-TXA2 and U46619 induced sustained aggregation. Blocking the IP receptor switched F2-TXA2-mediated reversible aggregation into sustained aggregation. Further BRET studies confirmed F2-TXA2-mediated IP receptor activation. F2-TXA2 rapidly and potently stimulated platelet TP receptor-mediated protein kinase C/P-pleckstrin, whereas IP-mediated protein kinase A/P-vasodilator-stimulated phosphoprotein was more delayed. CONCLUSION AND IMPLICATIONS: F-TXA2 is a close analogue to TXA2 used as a selective tool for TP receptor platelet activation. In contrast, F2-TXA2 acts on both TP and IP receptors differently over time, resulting in an initial wave of TP receptor-mediated platelet aggregation followed by IP receptor-induced reversibility of aggregation. This study reveals the potential difference in the temporal aspects of stimulatory and inhibitory pathways involved in platelet activation.

CryoET reveals actin filaments within platelet microtubules.

Crosstalk between the actin and microtubule cytoskeletons is important for many cellular processes. Recent studies have shown that microtubules and F-actin can assemble to form a composite structure where F-actin occupies the microtubule lumen. Whether these cytoskeletal hybrids exist in physiological settings and how they are formed is unclear. Here, we show that the short-crossover Class I actin filament previously identified inside microtubules in human HAP1 cells is cofilin-bound F-actin. Lumenal F-actin can be reconstituted in vitro, but cofilin is not essential. Moreover, actin filaments with both cofilin-bound and canonical morphologies reside within human platelet microtubules under physiological conditions. We propose that stress placed upon the microtubule network during motor-driven microtubule looping and sliding may facilitate the incorporation of actin into microtubules.

Post-surgical discharge opioid prescribing, use and handling after introduction of a stewardship program.

SummaryOpioids are often used to provide postsurgical analgesia but may cause harm if used inappropriately. We introduced an opioid stewardship program in three Melbourne hospitals to reduce the inappropriate use of opioids after patient discharge. The program had four pillars: prescriber education, patient education, a standardised quantity of discharge opioids, and general practitioner (GP) communication. Following introduction of the program, we undertook this prospective cohort study. The study aimed to describe post-program discharge opioid prescribing, patient opioid use and handling, and the impact of patient demographics, pain and surgical treatment factors on discharge prescribing. We also evaluated compliance with the program components. We recruited 884 surgical patients from the three hospitals during the ten-week study period. Discharge opioids were dispensed to 604 (74%) patients, with 20% receiving slow-release opioids. Junior medical staff undertook 95% of discharge opioid prescribing, which was guideline-compliant for 78% of patients. Of the patients discharged with opioids, a GP letter was sent for only 17%. Follow-up at two weeks was successful in 423 (70%) patients and in 404 (67%) at three months. At the three-month follow-up, 9.7% of patients reported ongoing opioid use; in preoperatively opioid naïve patients, the incidence was 5.5%. At the two-week follow-up, only 5% reported disposal of excess opioids, increasing to 26% at three months. Ongoing opioid therapy at three months in our study cohort (9.7%; 39/404) was associated with preoperative opioid consumption and higher pain scores at the three-month follow-up. The introduction of the opioid stewardship program resulted in highly guideline-compliant prescribing, but hospital-to-GP communication was uncommon and opioid disposal rates were low. Our findings suggest that opioid stewardship programs can improve postoperative opioid prescribing, use and handling, but the realisation of these gains will require effective program implementation.

Dorsal Spanning Plate for Perilunate Dislocations.

Purpose The purpose of this study was to compare radiographic outcomes in patients treated with the traditional method of open reduction, internal fixation (ORIF) and casting as compared with those treated with ORIF and dorsal spanning plate (DSP) fixation. We hypothesized that the application of a DSP to augment the repair of perilunate dislocations would maintain carpal stability while also allowing early loadbearing through the carpus. Materials and Methods This is a retrospective radiographic review of patients with a perilunate dislocation, who were treated with ORIF and casting or ORIF with a dorsal spanning plate between 2012-2018. Scapholunate (SL) and lunotriquetral (LT) intervals were measured immediately after the index surgery and after scheduled hardware removal. A total of 28 patients met inclusion criteria, including 13 cases with traditional treatment and 15 cases with dorsal spanning plate fixation. Results Comparison of the change in SL interval and LT interval between the 13 patients in the traditional treatment group and the 15 patients in the DSP group did not yield any clinically relevant variation after statistical analysis. Both groups demonstrated minimal change in the radiographic markers of carpal stability from postoperative radiographs obtained immediately after the index repair and after the removal of hardware. Conclusion DSP fixation placed at the index surgery with early loadbearing for the treatment of perilunate dislocation is not inferior to the current mainstay of treatment consisting of cast immobilization without loadbearing and does not confer any increased carpal instability in comparison to ORIF and casting.