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Background and Objective: Quantitative measures extracted from ventricular fibrillation (VF) waveform reflect the metabolic state of the myocardium and are associated with survival outcome. The quality of delivered chest compressions during cardiopulmonary resuscitation are also linked with survival. The aim of this research is to explore the viability and effectiveness of a thoracic impedance (TI) based chest compression (CC) guidance system to control CC depth within individual subjects and influence VF waveform properties., Methods: This porcine investigation includes an analysis of two protocols. CC were delivered in 2 min episodes at a constant rate of 110 CC min -1 . Subject-specific CC depth was controlled using a TI-thresholding system where CC were performed according to the amplitude (Z RMS, 0.125 to 1.250 Ω) of a band-passed TI signal (Z CC ). Protocol A was a retrospective analysis of a 12-porcine study to characterise the response of two VF waveform metrics: amplitude spectrum area (AMSA) and mean slope (MS), to varying CC quality. Protocol B was a prospective 12-porcine study to determine if changes in VF waveform metrics, due to CC quality, were associated with defibrillation outcome., Results: Protocol A: A directly proportional relationship was observed between Z RMS and CC depth applied within each subject (r = 0.90; p <0.001). A positive relationship was observed between Z RMS and both AMSA (p <0.001) and MS (p <0.001), where greater TI thresholds were associated with greater waveform metrics., Protocol B: MS was associated with return of circulation following defibrillation (odds ratio = 2.657; p = 0.043)., Conclusion: TI-thresholding was an effective way to control CC depth within-subjects. Compressions applied according to higher TI thresholds evoked an increase in AMSA and MS. The response in MS due to deeper CC resulted in a greater incidence of ROSC compared to shallow chest compressions., Competing Interests: Declaration of Competing Interest O. McAlister, A. Harvey and B. McCartney are employees of HeartSine Technologies Ltd. D. McEneaney is a medical advisor for HeartSine Technologies Ltd. The presented research was fully funded by HeartSine Technologies Ltd. within the scope of an industrially sponsored PhD program., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Quality of chest compressions (CC) during cardiopulmonary resuscitation (CPR) often do not meet guideline recommendations for rate and depth. This may be due to the fatiguing nature of physically compressing a patient's chest, meaning that CPR quality reduces over time., Objective: This analysis investigates the effect of CPR duration on the performance of continuous CCs delivered by firefighters equipped with CPR feedback devices., Methods: Data were collected from a first responder group which used CPR feedback and automatic external defibrillator devices when attending out-of-hospital cardiac arrest events. Depth and rate of CC were analysed for 134 patients. Mean CC depth and rate were calculated every 5 s during two-minute episodes of CPR. Regression models were created to evaluate the relationship between applied CC depth and rate as a function of time., Results: Mean (SD) CC depth during the investigation was 48 (9) mm. An inverse relationship was observed between CC depth and CPR duration, where CC depth decreased by 3.39 mm, over two-minutes of CPR (p < 0.001). Mean (SD) CC rate was 112.06 (5.87) compressions per minute. No significant relationship was observed between CC rate and CPR duration (p = 0.077). Mean depth was within guideline range for 33.58% of patient events, while guideline rate was observed in 92.54% of cases., Conclusions: A reduction in CC depth was observed during two-minutes of continuous CCs while CC rate was not affected. One third of patients received a mean CC depth within guideline range (50 to 60 mm)., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Many eukaryotes form multinucleated cells during their development. Some cells persist as such during their lifetime, others choose to cleave each nucleus individually using a specialized cytokinetic process known as cellularization. What is cellularization and how is it achieved across the eukaryotic tree of life? Are there common pathways among all species supporting a shared ancestry, or are there key differences, suggesting independent evolutionary paths? In this review, we discuss common strategies and key mechanistic differences in how cellularization is executed across vastly divergent eukaryotic species. We present a number of novel methods and non-model organisms that may provide important insight into the evolutionary origins of cellularization., Competing Interests: Conflict of interest statement Nothing declared, (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Aim: Automated external defibrillators (AEDs) use various shock protocols with different characteristics when deployed in pediatric mode. The aim of this study is to assess and compare the safety and efficacy of different AED pediatric protocols using novel experimental approaches., Methods: Two defibrillation protocols (A and B) were assessed across two studies: Protocol A: escalating (50-75-90 J) defibrillation waveform with higher voltage, shorter duration and equal phase durations. Protocol B; non-escalating (50-50-50 J) defibrillation waveform with lower voltage, longer duration and unequal phase durations.Experiment 1: Isolated shock damage was assessed following shocks to 12 anesthetized pigs. Animals were randomized into two groups, receiving three shocks from Protocol A (50-75-90 J) or B (50-50-50 J). Cardiac function, cardiac troponin I (cTnI), creatine phosphokinase (CPK) and histopathology were analyzed. Experiment 2: Defibrillation safety and efficacy were assessed through shock success, ROSC, ST-segment deviation and contractility following 16 randomized shocks from protocol A or B delivered to 10 anesthetized pigs in VF., Results: Experiment 1: No clinically meaningful difference in cTnI, CPK, ST-segment deviation, ejection fraction or histopathological damage was observed following defibrillation with either protocol. No difference was observed between protocols at any timepoint. Experiment 2: all defibrillation types demonstrated shock success and ROSC ≥ 97.5%. Post-ROSC contractility was similar between protocols., Conclusions: There is no evidence that administration of clinically relevant shock sequences, without experimental confounders, result in significant myocardial damage in this model of pediatric resuscitation. Typical variations in AED pediatric mode settings do not affect defibrillation safety and efficacy., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: BM, AH, AK, SM and OM are employed by HeartSine Technologies Ltd., Stryker Belfast. PC is a consultant paid by HeartSine Technologies Ltd., Stryker Belfast. DM sits on the HeartSine Technologies Ltd., Stryker Belfast Clinical Advisory Board and is provided remuneration (modest)., (© 2022 The Author(s).)

Background: Public access defibrillators (PADs) represent unique life-saving medical devices as they may be used by untrained lay rescuers. Collecting representative clinical data on these devices can be challenging. Here, we present results from a retrospective observational cohort study, describing real-world PAD utilisation over a 5-year period., Methods: Data were collected between October 2012 and October 2017. Responders voluntarily submitted electronic data downloaded from HeartSine PADs, and patient demographics and other details using a case report form in exchange for a replacement battery and electrode pack., Results: Data were collected for 977 patients (692 males, 70.8%; 255 females, 26.1%; 30 unknown, 3.1%). The mean age (SD) was 59 (18) years (range <1 year to 101 years). PAD usage occurred most commonly in homes (n=328, 33.6%), followed by public places (n=307, 31.4%) and medical facilities (n=128, 13.1%). Location was unknown in 40 (4.09%) events. Shocks were delivered to 354 patients. First shock success was 312 of 350 patients where it could be determined (89.1%, 95% CI 85.4% to 92.2%). Patients with reported response times ≤5 min were more likely to survive to hospital admission (89/296 (30.1%) vs 40/250 (16.0%), p<0.001). Response time was unknown for 431 events., Conclusion: This is the first study to report global PAD usage in voluntarily submitted, unselected real-world cases and demonstrates the real-world effectiveness of PADs, as confirmed by first shock success., Competing Interests: Competing interests: HT and OMA are employed by HeartSine Technologies Ltd and are PhD students at Ulster University. RB is employed by Ulster University. AH, AK, RF and BMC are employed by HeartSine Technologies Ltd. LD was employed by HeartSine Technologies Ltd at the time of data collection. JA is employed by the Belfast Health and Social Care Trust and is an unpaid member of the HeartSine Clinical Advisory Board. DME is employed by the Southern Health and Social Care Trust and is an unpaid member of the HeartSine Clinical Advisory Board., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Drosophila oogenesis is an excellent in vivo model for investigating cytoskeletal dynamics because of the rapid cytoskeletal remodeling that occurs at the end of stage 10; however, there are few robust tools for detecting microtubules in live complex tissues. The recent development of membrane permeable taxol-based fluorescent probes to label microtubules is significant technical progress, but the effectiveness of these probes and the potential stabilizing effects of the taxol derivative have not been well characterized in vivo. Here, we compared three commercially available taxol-derived microtubule labels to determine their efficacy and potential artifacts. We found that all three probes labeled microtubules with differences in permeability, brightness, and signal to noise ratio. Like taxol, however, all of the probes disrupted the F-actin cytoskeleton at higher concentrations. We also found that the efflux pump inhibitor, verapamil, increased the intensity of the label and modestly increased the severity of the F-actin defects. Of the three probes, Tubulin Tracker (ThermoScientific) was the most permeable and was brightest, with the highest signal to noise ratio. Furthermore, washing out the probe after a 30-min incubation significantly reduced the F-actin artifacts without compromising signal brightness., (© 2020 Wiley Periodicals, Inc.)

Brain decoding-the process of inferring a person's momentary cognitive state from their brain activity-has enormous potential in the field of human-computer interaction. In this study we propose a zero-shot EEG-to-image brain decoding approach which makes use of state-of-the-art EEG preprocessing and feature selection methods, and which maps EEG activity to biologically inspired computer vision and linguistic models. We apply this approach to solve the problem of identifying viewed images from recorded brain activity in a reliable and scalable way. We demonstrate competitive decoding accuracies across two EEG datasets, using a zero-shot learning framework more applicable to real-world image retrieval than traditional classification techniques., Competing Interests: During the course of this study one of the authors (Brian Murphy) has been under the employ of BrainWaveBank Ltd. as CSO. Although Brian is serving as the point of contact for access to one of the EEG datasets we analyse in this study, this dataset was created prior to the founding of BrainWaveBank and as such the funder has no association with the dataset. At this time Brian was under the employ of the University of Trento. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

The purpose of this study was to report both the radiographic and functional outcomes of patients undergoing knee arthrodesis with the Wichita Fusion Nail (WFN) within the Republic of Ireland and compare the results to existing literature. Patient charts and radiographs were reviewed on all patients who had a WFN implanted in Ireland to date. Patients were invited to complete a Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score as a functional assessment. Twenty-three patients were identified. Patients had an average of 8 (range: 0-26) knee surgeries prior to arthrodesis. The most common indication was failed arthroplasty due to recalcitrant infection (69.5%). Successful fusion occurred in 60.8% of patients. The mean time to fusion was 9.21 months. The mean WOMAC score was 58.55 with a range of 31 to 96. We found a rate of arthrodesis lower than that reported in other published series. However, the rate of major complications was comparable to those published previously, reflecting the often-challenging patient cohort. Our study shows that the WFN should not be viewed as a near-universally successful option to salvage an unreconstructable knee., Competing Interests: None., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Introduction: Diathermy is an integral part of many modern surgical procedures. While diathermy is generally accepted as 'safe', electrosurgery-induced injuries are among the more common causes for malpractice litigation. The purpose of this study was to evaluate the awareness among surgeons of the principles, risks, precautions and appropriate use of diathermy., Methods: All surgeons employed from Senior House Officer (SHO) to Consultant grade in two teaching hospitals were surveyed. Sixty-three surgeons were asked to complete an anonymous questionnaire, which recorded level of training and addressed competence in principles, hazards, and precautions to be taken with diathermy., Results: Eight Consultants, 5 Specialist Registrars, 19 Registrars and 13 SHO's responded (71% response). All but three subspecialties were represented. Eighty-two percent (37/45) had no formal diathermy training. Despite 89% (40/45) of surgeons regarding diathermy as a safe instrument, 56% felt they had inadequate understanding of the principles and failed to demonstrate an appropriate awareness of the potential risks. Fifty seven percent exhibited a dangerous lack of awareness in managing equipment not yielding the desired effect and 22% were unaware of any patient groups requiring special caution. Only 42% wanted formal training., Conclusion: Our results show a dearth of awareness among surgeons regarding diathermy. Given our findings, we urge a shift in attitude towards diathermy, with surgeons adopting a more cautious and safe approach to diathermy use. We recommend that formal training be introduced as a hospital based initiative.

Uncertainty is an important part of the illness experience. Mishel elaborated a theory of uncertainty in acute illness and later expanded the framework to account for uncertainty in chronic illness. Researchers subsequently have investigated the causes and outcomes associated with the uncertainty in illness experience across a variety of medical conditions. The current study applies and extends Mishel's model within the context of HIV illness-related uncertainty. In this qualitative study, focus group methods were used to examine the nature of illness uncertainty experienced by persons living with HIV or AIDS. Findings confirm Mishel's contention that the causes of uncertainty extend beyond those of medical diagnosis, treatment, and recovery to personal and social aspects of daily life. Identified sources of uncertainty may have important mental health and quality of life implications.

Proper positioning of mitotic spindles ensures equal allocation of chromosomes to daughter cells. This often involves interactions between spindle and astral microtubules and cortical actin. In yeast and Caenorhabditis elegans, some of the protein machinery that connects spindles and cortex has been identified but, in most animal cells, this process remains mysterious. Here, we report that the tumour suppressor homologue APC2 and its binding partner Armadillo both play roles in spindle anchoring during the syncytial mitoses of early Drosophila embryos. Armadillo, alpha-catenin and APC2 all localize to sites of cortical spindle attachment. APC2-Armadillo complexes often localize with interphase microtubules. Zeste-white 3 kinase, which can phosphorylate Armadillo and APC, is also crucial for spindle positioning and regulates the localization of APC2-Armadillo complexes. Together, these data suggest that APC2, Armadillo and alpha-catenin provide an important link between spindles and cortical actin, and that this link is regulated by Zeste-white 3 kinase.

Merlin, the Drosophila homologue of the human tumor suppressor gene Neurofibromatosis 2 (NF2), is required for the regulation of cell proliferation and differentiation. To better understand the cellular functions of the NF2 gene product, Merlin, recent work has concentrated on identifying proteins with which it interacts either physically or functionally. In this article, we describe genetic screens designed to isolate second-site modifiers of Merlin phenotypes from which we have identified five multiallelic complementation groups that modify both loss-of-function and dominant-negative Merlin phenotypes. Three of these groups, Group IIa/scribbler (also known as brakeless), Group IIc/blistered, and Group IId/net, are known genes, while two appear to be novel. In addition, two genes, Group IIa/scribbler and Group IIc/blistered, alter Merlin subcellular localization in epithelial and neuronal tissues, suggesting that they regulate Merlin trafficking or function. Furthermore, we show that mutations in scribbler and blistered display second-site noncomplementation with one another. These results suggest that Merlin, blistered, and scribbler function together in a common pathway to regulate Drosophila wing epithelial development.

Neurofibromatosis-2 is an inherited disorder characterized by the development of benign schwannomas and other Schwann-cell-derived tumors associated with the central nervous system. The Neurofibromatosis-2 tumor suppressor gene encodes Merlin, a member of the Protein 4.1 superfamily most closely related to Ezrin, Radixin and Moesin. This discovery suggested a novel function for Protein 4.1 family members in the regulation of cell proliferation; proteins in this family were previously thought to function primarily to link transmembrane proteins to underlying cortical actin. To understand the basic cellular functions of Merlin, we are investigating a Drosophila Neurofibromatosis-2 homologue, Merlin. Loss of Merlin function in Drosophila results in hyperplasia of the affected tissue without significant disruptions in differentiation. Similar phenotypes have been observed for mutations in another Protein 4.1 superfamily member in Drosophila, expanded. Because of the phenotypic and structural similarities between Merlin and expanded, we asked whether Merlin and Expanded function together to regulate cell proliferation. In this study, we demonstrate that recessive loss of function of either Merlin or expanded can dominantly enhance the phenotypes associated with mutations in the other. Consistent with this genetic interaction, we determined that Merlin and Expanded colocalize in Drosophila tissues and cells, and physically interact through a conserved N-terminal region of Expanded, characteristic of the Protein 4.1 family, and the C-terminal domain of Merlin. Loss of function of both Merlin and expanded in clones revealed that these proteins function to regulate differentiation in addition to proliferation in Drosophila. Further genetic analyses suggest a role for Merlin and Expanded specifically in Decapentaplegic-mediated differentiation events. These results indicate that Merlin and Expanded function together to regulate proliferation and differentiation, and have implications for understanding the functions of other Protein 4.1 superfamily members.

The tumor suppressor adenomatous polyposis coli (APC) negatively regulates Wingless (Wg)/Wnt signal transduction by helping target the Wnt effector beta-catenin or its Drosophila homologue Armadillo (Arm) for destruction. In cultured mammalian cells, APC localizes to the cell cortex near the ends of microtubules. Drosophila APC (dAPC) negatively regulates Arm signaling, but only in a limited set of tissues. We describe a second fly APC, dAPC2, which binds Arm and is expressed in a broad spectrum of tissues. dAPC2's subcellular localization revealed colocalization with actin in many but not all cellular contexts, and also suggested a possible interaction with astral microtubules. For example, dAPC2 has a striking asymmetric distribution in neuroblasts, and dAPC2 colocalizes with assembling actin filaments at the base of developing larval denticles. We identified a dAPC2 mutation, revealing that dAPC2 is a negative regulator of Wg signaling in the embryonic epidermis. This allele acts genetically downstream of wg, and upstream of arm, dTCF, and, surprisingly, dishevelled. We discuss the implications of our results for Wg signaling, and suggest a role for dAPC2 as a mediator of Wg effects on the cytoskeleton. We also speculate on more general roles that APCs may play in cytoskeletal dynamics.

Merlin, the product of the Neurofibromatosis type 2 (NF2) tumor-suppressor gene, is a member of the protein 4.1 superfamily that is most closely related to ezrin, radixin, and moesin (ERM). NF2 is a dominantly inherited disease characterized by the formation of bilateral acoustic schwannomas and other benign tumors associated with the central nervous system. To understand its cellular functions, we are studying a Merlin homologue in Drosophila. As is the case for NF2 tumors, Drosophila cells lacking Merlin function overproliferate relative to their neighbors. Using in vitro mutagenesis, we define functional domains within Merlin required for proper subcellular localization and for genetic rescue of lethal Merlin alleles. Remarkably, the results of these experiments demonstrate that all essential genetic functions reside in the plasma membrane- associated NH2-terminal 350 amino acids of Merlin. Removal of a seven-amino acid conserved sequence within this domain results in a dominant-negative form of Merlin that is stably associated with the plasma membrane and causes overproliferation when expressed ectopically in the wing. In addition, we provide evidence that the COOH-terminal region of Merlin has a negative regulatory role, as has been shown for ERM proteins. These results provide insights into the functions and functional organization of a novel tumor suppressor gene.

For their patients who enter a nursing home, physicians need to know how to perform an efficient and effective visit. With a structured, methodical approach the initial and follow-up visits can be done within 15 minutes per patient. Each visit can include review of diagnoses and medications; input from the patient, nursing staff, and families; vital signs and weights; physical exam; lab results; and review of the interdisciplinary care plan. An assessment that genuinely contributes to the care plan will enhance the physician's effectiveness and satisfaction in long-term care practice.

Reverse genetic analysis in Drosophila has been greatly aided by a growing collection of lethal P transposable element insertions that provide molecular tags for the identification of essential genetic loci. However, because the screens performed to date primarily have generated autosomal P-element insertions, this collection has not been as useful for performing reverse genetic analysis of X-linked genes. We have designed a reverse genetic screen that takes advantage of the hemizygosity of the X chromosome in males together with a cosmid-based transgene that serves as an autosomally linked duplication of a small region of the X chromosome. The efficacy and efficiency of this method is demonstrated by the isolation of mutations in Drosophila homologues of two well-studied genes, the human Neurofibromatosis 2 tumor suppressor and the yeast CDC42 gene. The method we describe should be of general utility for the isolation of mutations in other X-linked genes, and should also provide an efficient method for the isolation of new allcles of existing X-linked or autosomal mutations in Drosophila.

Components of a protein tyrosine phosphorylation/dephosphorylation network were identified in the cyanobacterium Anabaena sp. strain PCC 7120. Three phosphotyrosine (P-Tyr) proteins of 27, 36, and 52 kDa were identified through their conspicuous immunoreactions with RC20H monoclonal antibodies specific for P-Tyr. These immunoreactions were outcompeted completely by free P-Tyr (5 mM) but not by phosphoserine or phosphothreonine. The P-Tyr content of the three major P-Tyr proteins and several minor proteins increased with their time of incubation in the presence of Mg-ATP and the protein phosphatase inhibitors sodium orthovanadate and sodium fluoride. Incubation of the same extracts with [gamma-32P]ATP but not [alpha-32P]ATP led to the phosphorylation of five polypeptides with molecular masses of 20, 27, 52, 85, and 100 kDa. Human placental protein tyrosine phosphatase 1B, with absolute specificity for P-Tyr, liberated significant quantities of 32Pi from four of the polypeptides, confirming that a portion of the protein-bound phosphate was present as 32P-Tyr. Alkaline phosphatase and the dual-specificity protein phosphatase IphP from the cyanobacterium Nostoc commune UTEX 584 also dephosphorylated these proteins and did so with greater apparent efficiency. Two of the polypeptides were partially purified, and phosphoamino analysis identified 32P-Tyr, [32P]phosphoserine, and [32P]phosphothreonine. Anabaena sp. strain PCC 7120 cell extracts contained a protein tyrosine phosphatase activity that was abolished in the presence of sodium orthovanadate and inhibited significantly by the sulfhydryl-modifying agents p-hydroxymercuriphenylsulfonic acid and p-hydroxymercuribenzoate as well as by heparin. In Anabaena sp. strain PCC 7120 the presence and/or phosphorylation status of P-Tyr proteins was influenced by incident photon flux density.

Interest in members of the protein 4.1 super-family, which includes the ezrin-radixin-moesin (ERM) group, has been stimulated recently by the discovery that the human neurofibromatosis 2 (NF2) tumor suppressor gene encodes an ERM-like protein, merlin. Although many proteins in this family are thought to act by linking the actin-based cytoskeleton to transmembrane proteins, the cellular functions of merlin have not been defined. To investigate the cellular and developmental functions of these proteins, we have identified and characterized Drosophila homologues of moesin (Dmoesin) and of the NF2 tumor suppressor merlin (Dmerlin). Using specific antibodies, we show that although these proteins are frequently coexpressed in developing tissues, they display distinct subcellular localizations. While Dmoesin is observed in continuous association with the plasma membrane, as is typical for an ERM family protein, Dmerlin is found in punctuate structures at the membrane and in the cytoplasm. Investigation of Dmerlin cultured cells demonstrates that it is associated with endocytic compartments. As a result of these studies, we propose that the merlin protein has unique functions in the cell which differ from those of other ERM family members.