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Introduction: Determining fluid status prior to resuscitation provides a more accurate guide for appropriate fluid administration in the setting of undifferentiated hypotension. Emergency Department (ED) point of care ultrasound (PoCUS) has been proposed as a potential non-invasive, rapid, repeatable investigation to ascertain inferior vena cava (IVC) characteristics. Our goal was to determine the feasibility of using PoCUS to measure IVC size and collapsibility. Methods: This was a planned secondary analysis of data from a prospective multicentre international study investigating PoCUS in ED patients with undifferentiated hypotension. We prospectively collected data on IVC size and collapsibility using a standard data collection form in 6 centres. The primary outcome was the proportion of patients with a clinically useful (determinate) scan defined as a clearly visible intrahepatic IVC, measurable for size and collapse. Descriptive statistics are provided. Results: A total of 138 scans were attempted on 138 patients; 45.7% were women and the median age was 58 years old. Overall, one hundred twenty-nine scans (93.5%; 95% CI 87.9 to 96.7%) were determinate. 131 (94.9%; 89.7 to 97.7%) were determinate for IVC size, and 131 (94.9%; 89.7 to 97.7%) were determinate for collapsibility. Conclusion: In this analysis of 138 ED patients with undifferentiated hypotension, the vast majority of PoCUS scans to investigate IVC characteristics were determinate. Future work should include analysis of the value of IVC size and collapsibility in determining fluid status in this group.
High-security hospital patients are often complex in presentation characterised by treatment resistance, medication non-concordance and history of violence. Paliperidone is licensed as both an oral and depot antipsychotic for the treatment of schizophrenia. Whilst there is data for the effectiveness of paliperidone palmitate (PP), there are no studies involving patients in forensic settings or those with comorbid personality disorder.
To determine the effects of PP on violence, aggression and personality pathology.
To evaluate the clinical effectiveness of PP.
This was a retrospective service evaluation involving 11 patients. Medical records and interviews with the treating psychiatrist were used to formulate clinical global impression (CGI) and to identify incidents of violence. The effect on personality symptom domains; cognitive-perceptual, impulsive-behavioural dyscontrol and affective dysregulation was ascertained, as well as engagement with occupational and psychological therapies.
Six patients were being prescribed PP. All 6 showed improvement in the CGI score with benefits in the symptom domains. Two patients demonstrated a reduction in violence risk and 2 remained incident-free. There was improvement in engagement with therapies. Benefits were also seen in aspects of personality for those who had discontinued PP.
This pragmatic study of a small but complex patient group demonstrated that PP was effective in reducing symptoms of schizophrenia. Additionally and for the first time, it was shown that PP was also effective in reducing violence as well as improving personality pathology dimensions in a comorbid patient. This could have significant implications for management of high-security patients.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Introduction: Les patients ayant un retour de circulation spontanée (RCS) durant la phase préhospitalière de leur réanimation suite à un arrêt cardiaque extrahospitalier (ACEH) ont un meilleur taux de survie que ceux n'en ayant pas. La durée des efforts de réanimation avant l'initiation d'un transport ne varie généralement pas en fonction du rythme initial observé. Cette étude vise à comparer la durée des manœuvres de réanimation nécessaire afin de générer la majorité des RCS préhospitaliers et des RCS préhospitaliers menant à une survie en fonction du rythme initial. Methods: La présente étude de cohorte a été réalisée à partir des bases de données collectées de la Corporation d'Urgences-santé dans la région de Montréal entre 2010 et 2015. Les patients avec un ACEH d'origine médicale ont été inclus. Les patients dont l'ACEH était témoigné par les paramédics ont été exclus, tout comme ceux dont le rythme initial était inconnu. Nous avons comparé entre les groupes (rythme défibrillable [RD], activité électrique sans pouls [AESP] et asystolie) les taux de RCS préhospitalier et le temps nécessaires pour obtenir une majorité des RCS préhospitaliers et des RCS préhospitaliers menant à une survie. Results: Un total de 6002 patients (3851 hommes et 2151 femmes) d'un âge moyen de 52 ans ( ±10) ont été inclus dans l’étude, parmi lesquels 563 (9%) ont survécu jusqu’à leur congé hospitalier et 1310 (22%) ont obtenu un RCS préhospitalier. Un total de 1545 (26%) patients avaient un RD, 1654 (28%) une AESP et 2803 (47%) une asystolie. Les patients avec un RD ont obtenu plus fréquemment un RCS préhospitalier et un RCS préhospitalier menant à une survie que les patients avec une AESP qui eux même avaient un meilleur pronostic que ceux avec une asystolie initial (777 patients [55%] vs 385 [23%] vs 148 [5%], p < 0,001; 431 [28%] vs 85 [5%] vs 7 [0,2%], p < 0,001, respectivement). Les RCS survenaient également plus rapidement lorsque le rythme initial était un RD (13 minutes [ ±12] vs 18 [ ±13] vs 25 [ ±12], p < 0,001). Cependant, une période de réanimation plus longue était nécessaire afin d'obtenir 95% des RCS préhospitaliers menant à une survie pour les patients avec un RD (26 minutes vs 21 minutes vs 21 minutes). Conclusion: Les patients avec un rythme initial défibrillable suite à leur ACEH sont à meilleur pronostic. Il serait envisageable de transporter plus rapidement vers l'hôpital les patients avec une AESP ou une asystolie que ceux avec un rythme défibrillable si l'arrêt des manœuvres n'est pas envisagé.
Introduction: Les patients dont l'arrêt cardiaque extrahospitalier (ACEH) n'a pas été témoigné sont généralement exclus des protocoles de réanimation par circulation extracorporelle puisque le délai avant l'initiation de leur réanimation est inconnu. Il a été proposé que la présence d'un rythme initial défibrillable (RD) est fortement suggestif une très courte période avant l'initiation des manœuvres de réanimation. La présente étude vise à décrire l'association entre la durée avant l'initiation de la réanimation et la présence d'un RD chez des patients souffrant d'un ACEH. Methods: Cette étude de cohorte a été réalisée à partir des bases de données collectées de la Corporation d'Urgences-santé dans la région de Montréal entre 2010 et 2015. Les patients dont l'arrêt était témoigné, mais dont les témoins n'ont pas entamé de manœuvres de réanimation, ont été inclus. Nous avons également inclus les patients dont l'arrêt était témoigné par les paramédics comme groupe contrôle (durée avant l'initiation de la réanimation = 0 minute). Les patients avec un retour de circulation spontanée avant l'arrivée des services préhospitaliers ont été exclus, tout comme ceux dont le rythme initial était inconnu. Nous avons décrit l’évolution de la proportion de chacun des rythmes et construit une régression logistique multivariée ajustant pour les variables sociodémographiques et cliniques pertinentes. Results: Un total de 1751 patients (1173 hommes et 578 femmes) d'un âge moyen de 69 ans (±16) ont été inclus dans l'analyse principale, parmi lesquels 603 (34%) avaient un RD. Un total de 663 autres patients ont vu leur ACEH témoigné directement par les paramédics. Un plus court délai avant l'initiation des manœuvres est associé à la présence d'un RD (rapport de cotes ajusté = 0,97 [intervalle de confiance à 95% 0,94-0,99], p = 0,016). Cependant, cette relation n'est pas linéaire et la proportion de RD ne diminue pas avant notablement jusqu’à ce que 15 minutes s’écoulent avant le début de la réanimation (0 min = 35%, 1-5 min = 37%, 5-10 min = 35%, 10-15 min = 34%, +de 15 min = 16%). Conclusion: Bien que la proportion de patients avec un RD diminue lorsque le délai augmente avant l'initiation des manœuvres, cette relation ne semble pas linéaire. La baisse principale de la proportion de patients avec RD semble se produire suite à la quinzième minute de délai avant le début de la réanimation.
Introduction: La réanimation par circulation extracorporelle (R-CEC) permet potentiellement d'améliorer la survie de patients souffrant d'un arrêt cardiaque extrahospitalier (ACEH) réfractaire aux traitements habituels. Cette technique, se pratiquant généralement en centre hospitalier (CH), doit être réalisée le plus précocement possible. Un transport vers le CH en temps opportun est donc nécessaire. Cette étude vise à décrire la durée nécessaire des manœuvres de réanimation préhospitalières afin d'optimiser le moment du départ vers le CH dans le but d'obtenir un maximum de retour de circulation spontanée (RCS) préhospitalier. Methods: La présente étude de cohorte a été réalisée à partir des bases de données collectées de la Corporation d'Urgences-santé dans la région de Montréal entre 2010 et 2015. Les patients éligibles à une R-CEC selon les critères locaux ont été inclus (<65 ans, rythme initial défibrillable, arrêt témoigné avec réanimation par un témoin). Les patients ayant eu un arrêt devant les paramédics ont été exclus, tout comme ceux avec un RCS avant l'arrivée des services préhospitaliers. Nous avons calculé la sensibilité et la spécificité à différents seuils afin de prédire un RCS préhospitalier et une survie au congé hospitalier. Une courbe ROC a également été construite. Results: Un total de 236 patients (207 hommes et 29 femmes) d'un âge moyen de 52 ans (±10) ont été inclus dans l’étude, parmi lesquels 93 (39%) ont survécu jusqu’à leur congé hospitalier et 136 (58%) ont obtenu un RCS préhospitalier. Le délai moyen avant leur RCS était de 13 minutes (±10). Plus de 50% des survivants avaient eu un RCS moins de 8 minutes après l'initiation des manœuvres de réanimation par les intervenants préhospitaliers, et plus de 90% avant 24 minutes. Plus de 50% de tous les RCS survenaient dans les 10 premières minutes de réanimation et plus de 90% dans les 31 premières minutes. La courbe ROC montrait visuellement que le délai avant le RCS maximisant la sensibilité et la spécificité pour prédire la survie chez ces patients était à 22 minutes (Sensibilité = 90%, spécificité = 78%; aire sous la courbe = 0,89 [intervalle de confiance à 95% 0,84-0,93]). Conclusion: Le départ vers le CH pourrait être considéré pour ces patients entre 8 et 24 minutes après l'initiation des manœuvres. Une période de réanimation de 22 minutes semble être le meilleur compromis à cet égard.
Expert-consensus guidelines have been developed for how members of the public should assist a person with a mental health problem or in a mental health crisis.
This review aimed to examine the range of guidelines that have been developed and how these have been implemented in practice.
A narrative review was carried out based on a systematic search for literature on the development or implementation of the guidelines.
The Delphi method has been used to develop a wide range of guidelines for English-speaking countries, Asian countries and a number of other cultural groups. The primary implementation has been through informing the content of training courses.
Further work is needed on guidelines for low- and middle-income countries.
Declaration of interest
A.F.J. is an unpaid member of the Board of Mental Health First Aid International (trading as Mental Health First Aid Australia), which is a not-for-profit organisation.
To examine neonatal risk factors associated with recurrent Staphylococcus aureus colonization and to determine the genetic relatedness of S. aureus strains cultured from neonates before and after decolonization.
Single-center retrospective cohort study of neonates admitted to the neonatal intensive care unit (NICU) from April 2013 to December 2015, during which weekly nasal cultures from hospitalized NICU patients were routinely obtained for S. aureus surveillance.
Johns Hopkins Hospital’s 45-bed level IV NICU in Baltimore, Maryland.
Demographics and clinical data were collected on all neonates admitted to the NICU with S. aureus nasal colonization who underwent mupirocin-based decolonization during the study period. A decolonized neonate was defined as a neonate with ≥1 negative culture after intranasal mupirocin treatment. Pulsed-field gel electrophoresis was used for strain typing.
Of 2,060 infants screened for S. aureus, 271 (13%) were colonized, and 203 of these 271 (75%) received intranasal mupirocin. Of those treated, 162 (80%) had follow-up surveillance cultures, and 63 of these 162 infants (39%) developed recurrent colonization after treatment. The S. aureus strains were often genetically similar before and after decolonization. The presence of an endotracheal tube or nasal cannula/mask was associated with an increased risk of recurrent S. aureus colonization (hazard ratio [HR], 2.65; 95% confidence interval [CI], 1.19–5.90; and HR, 2.21; 95% CI, 1.02–4.75, respectively).
Strains identified before and after decolonization were often genetically similar, and the presence of invasive respiratory devices increased the risk of recurrent S. aureus nasal colonization in neonates. To improve decolonization efficacy, alternative strategies may be needed.
Background: Heterozygous loss-of-function mutations in the synaptic scaffolding gene SHANK2 are strongly associated with autism spectrum disorder (ASD). However, their impact on the function of human neurons is unknown. Derivation of induced pluripotent stem cells (iPSC) from affected individuals permits generation of live neurons to answer this question. Methods: We generated iPSCs by reprogramming dermal fibroblasts of neurotypic and ASD-affected donors. To isolate the effect of SHANK2, we used CRISPR/Cas9 to knock out SHANK2 in control iPSCs and correct a heterozygous nonsense mutation in ASD-affected donor iPSCs. We then derived cortical neurons from SOX1+ neural precursor cells differentiated from these iPSCs. Using a novel assay that overcomes line-to-line variability, we compared neuronal morphology, total synapse number, and electrophysiological properties between SHANK2 mutants and controls. Results: Relative to controls, SHANK2 mutant neurons have increased dendrite complexity, dendrite length, total synapse number (1.5-2-fold), and spontaneous excitatory postsynaptic current (sEPSC) frequency (3-7.6-fold). Conclusions: ASD-associated heterozygous loss-of-function mutations in SHANK2 increase synaptic connectivity among human neurons by increasing synapse number and sEPSC frequency. This is partially supported by increased dendrite length and complexity, providing evidence that SHANK2 functions as a suppressor of dendrite branching during neurodevelopment.
n-3 PUFA are lipids that play crucial roles in immune-regulation, cardio-protection and neurodevelopment. However, little is known about the role that these essential dietary fats play in modulating caecal microbiota composition and the subsequent production of functional metabolites. To investigate this, female C57BL/6 mice were assigned to one of three diets (control (CON), n-3 supplemented (n3+) or n-3 deficient (n3−)) during gestation, following which their male offspring were continued on the same diets for 12 weeks. Caecal content of mothers and offspring were collected for 16S sequencing and metabolic phenotyping. n3− male offspring displayed significantly less % fat mass than n3+ and CON. n-3 Status also induced a number of changes to gut microbiota composition such that n3− offspring had greater abundance of Tenericutes, Anaeroplasma and Coriobacteriaceae. Metabolomics analysis revealed an increase in caecal metabolites involved in energy metabolism in n3+ including α-ketoglutaric acid, malic acid and fumaric acid. n3− animals displayed significantly reduced acetate, butyrate and total caecal SCFA production. These results demonstrate that dietary n-3 PUFA regulate gut microbiota homoeostasis whereby n-3 deficiency may induce a state of disturbance. Further studies are warranted to examine whether these microbial and metabolic disturbances are causally related to changes in metabolic health outcomes.
We briefly introduce the VLBI maser astrometric analysis of IRAS 18043–2116 and IRAS 18113–2503, two remarkable and unusual water fountains with spectacular bipolar bow shocks in their high-speed collimated jet-driven outflows. The 22 GHz H2O maser structures and velocities clearly show that the jets are formed in very short-lived, episodic outbursts, which may indicate episodic accretion in an underlying binary system.
Pregnant women, children under 2 and the first thousand days of life have been principal targets for Developmental Origins of Health and Disease interventions. This paradigm has been criticized for laying responsibility for health outcomes on pregnant women and mothers and through the thousand days focus inadvertently deflecting attention from other windows for intervention. Drawing on insights from the South African context, this commentary argues for integrated and inclusive interventions that encompass broader social framings. First, future interventions should include a wider range of actors. Second, broader action frameworks should encompass life-course approaches that identify multiple windows of opportunity for intervention. Using two examples – the inclusion of men, and engagement with adolescents – this commentary offers strategies for producing more inclusive interventions by using a broader social framework.
Introduction: Patients suffering from out-of-hospital cardiac arrest (OHCA) are frequently transported to the closest hospital after return of spontaneous circulation (ROSC). Percutaneous coronary intervention (PCI) is often indicated as a diagnostic and therapeutic procedure following OHCA. This study aimed to determine the association between the type of destination hospital (PCI-capable or not) and survival to discharge for patients with OHCA and prehospital ROSC. We hypothesized that being transported to a PCI-capable hospital would be associated with a higher survival to discharge. Methods: The present study used a registry of adult OHCA between 2010 and 2015 in Montréal, Canada. We included adult patients with non-traumatic OHCA and prehospital ROSC. The association of interest was evaluated with a multivariate logistic regression model to control for demographic and clinical variables (age, gender, time of day, initial rhythm, witnessed arrest, bystander CPR, presence of first responders or advanced care paramedics, prehospital supraglottic airway placement, delay before paramedics’ arrival). Assuming a survival rate of 40% and 75% of the variability explained by other factors included in the model, more than 1200 patients needed to be included to detect an absolute difference of 10% in survival between both groups with a power of more than 90%. Results: A total of 1691 patients (1140 men and 551 women) with a mean age of 64 years (standard deviation 17) were included, of which 1071 (63%) were transported to a PCI-capable hospital. Among all patients, 704 patients (42%) survived to hospital discharge. We observed a significant independent association between survival to discharge and being transported to a PCI-capable hospital (adjusted odds ratio [AOR] 1.46 [95% confidence interval 1.09-1.96]) after controlling for confounding variables. Having an initial shockable rhythm and presence of first responders also increased survival to discharge (AORs 3.67 [95% confidence interval 2.75-4.88] and 1.53 [95% confidence interval 1.12-2.09], respectively). Conclusion: Patients experiencing ROSC after OHCA could benefit from a direct transport to a PCI-capable hospital. This benefit might also be related to unmeasured interventions other than PCI these hospitals can provide (e.g. high-level intensive care or cardiovascular surgery).
From its beginning in 1938 through to the 1950s, ECT enjoyed considerable popularity for the treatment of schizophrenia. As one of the very few available treatments, it appeared to offer rapid alleviation of psychotic symptoms, particularly in the acutely ill, and was said to be without significant risks. Nevertheless, the availability of antipsychotic drugs from 1953, together with increasing opposition to the use of ECT, led to its gradual decline through the 1960s and 1970s (Fink, 2001). A resurgence of interest in the 1980s in its use to augment the action of drugs in individuals resistant to antipsychotics was eclipsed with the arrival of atypical antipsychotics, particularly clozapine, for the pharmacotherapy of treatment-resistant schizophrenia. The finding that a proportion of patients have symptoms that fail to respond to clozapine has prompted investigation of combining this drug with ECT. In addition, many psychiatrists see ECT as the treatment of choice for catatonic schizophrenia.
It is remarkable that, despite being available for more than 60 years, there are few good-quality controlled trials of ECT for schizophrenia. This has not been rectified since the publication of the previous edition of The ECT Handbook (Scott, 2005), but a number of excellent reviews of the evidence is available (Johns & Thompson, 1995; Krueger & Sackeim, 1995; Fink & Sackeim, 1996; Lehman et al, 1998). These were supplemented by a systematic review as part of the Cochrane Collaboration (Tharyan & Adams, 2005). This chapter has been updated slightly to incorporate additions to the literature since the last edition of the Handbook.
A comparison of real ECT against ‘sham’ ECT is the most rigorous method of establishing efficacy, comparable to a pharmaceutical placebo-controlled trial. In sham ECT, the control group undergoes the full ECT procedure with the exception of the stimulus, controlling for all extraneous influences on outcome. The design was developed in the 1950s, and it often included a group who received a subconvulsive stimulus. These studies are fraught with ethical and methodological difficulties and few have been published since 1965. Moreover, a lack of operationalised diagnostic criteria, compounded by an overinclusive approach to schizophrenia in the USA, often resulted in the misdiagnosis of affective psychoses.
This study aimed to assess the merit and suitability of individual functional units (FU) in expressing greenhouse gas emissions intensity in different dairy production systems. An FU provides a clearly defined and measurable reference to which input and output data are normalised. This enables the results from life-cycle assessment (LCA) of different systems to be treated as functionally equivalent. Although the methodological framework of LCA has been standardised, selection of an appropriate FU remains ultimately at the discretion of the individual study. The aim of the present analysis was to examine the effect of different FU on the emissions intensities of different dairy production systems. Analysis was based on 7 years of data (2004 to 2010) from four Holstein-Friesian dairy systems at Scotland’s Rural College’s long-term genetic and management systems project, the Langhill herd. Implementation of LCA accounted for the environmental impacts of the whole-farm systems and their production of milk from ‘cradle to farm gate’. Emissions intensity was determined as kilograms of carbon dioxide equivalents referenced to six FU: UK livestock units, energy-corrected milk yield, total combined milk solids yield, on-farm land used for production, total combined on- and off-farm land used for production, and the proposed new FU–energy-corrected milk yield per hectare of total land used. Energy-corrected milk was the FU most effective for reflecting differences between the systems. Functional unit that incorporated a land-related aspect did not find difference between systems which were managed under the same forage regime, despite their comprising different genetic lines. Employing on-farm land as the FU favoured grazing systems. The proposed dual FU combining both productivity and land use did not differentiate between emissions intensity of systems as effectively as the productivity-based units. However, this dual unit displayed potential to quantify in a simple way the positive or negative outcome of trade-offs between land and production efficiencies, in which improvement in emissions intensity using one FU may be accompanied by deterioration using another FU. The perceived environmental efficiencies of different dairy production systems in terms of their emissions intensities were susceptible to change based upon the FU employed, and hence the FU used in any study needs to be taken into account in the interpretation of results.
Accurate models of X-ray absorption and re-emission in partly stripped ions are necessary to calculate the structure of stars, the performance of hohlraums for inertial confinement fusion and many other systems in high-energy-density plasma physics. Despite theoretical progress, a persistent discrepancy exists with recent experiments at the Sandia Z facility studying iron in conditions characteristic of the solar radiative–convective transition region. The increased iron opacity measured at Z could help resolve a longstanding issue with the standard solar model, but requires a radical departure for opacity theory. To replicate the Z measurements, an opacity experiment has been designed for the National Facility (NIF). The design uses established techniques scaled to NIF. A laser-heated hohlraum will produce X-ray-heated uniform iron plasmas in local thermodynamic equilibrium (LTE) at temperatures
eV and electron densities
. The iron will be probed using continuum X-rays emitted in a
diameter source from a 2 mm diameter polystyrene (CH) capsule implosion. In this design,
of the NIF beams deliver 500 kJ to the
mm diameter hohlraum, and the remaining
directly drive the CH capsule with 200 kJ. Calculations indicate this capsule backlighter should outshine the iron sample, delivering a point-projection transmission opacity measurement to a time-integrated X-ray spectrometer viewing down the hohlraum axis. Preliminary experiments to develop the backlighter and hohlraum are underway, informing simulated measurements to guide the final design.
A new organometallic halide perovskite (OHP) synthesis method, whereby a polymer melt is used to thermodynamically drive the reaction that forms OHP crystallites, is demonstrated. The synthesis method allows for the facile encapsulation of moisture-sensitive OHP without the loss of simplicity during fabrication, which makes OHP materials so attractive for the photovoltaic industry. Degradation of OHP crystallites embedded in a polystyrene matrix was studied using UV-Vis absorbance over a period of several days. The OHP crystallites degrade as a result of the reversible nature of the reaction that forms the crystallites. After the reversion to precursors (PbI2 and CH3NH3I) the CH3NH3I irreversibly degrades  allowing the degradation to be tracked via optical interrogation. Additionally, surface morphology and elemental analysis of fabricated samples was carried out using SEM/EDS techniques.