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1.
Phys Rev E ; 110(1-1): 014125, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39160916

RÉSUMÉ

Understanding the entropy production of systems strongly coupled to thermal baths is a core problem of both quantum thermodynamics and mesoscopic physics. While many techniques exist to accurately study entropy production in such systems, they typically require a microscopic description of the baths, which can become numerically intractable to study for large systems. Alternatively an open-systems approach can be employed with all the nuances associated with various levels of approximation. Recently, the mesoscopic leads approach has emerged as a powerful method for studying such quantum systems strongly coupled to multiple thermal baths. In this method, a set of discretized lead modes, each locally damped, provide a Markovian embedding. Here we show that this method proves extremely useful to describe entropy production of a strongly coupled open quantum system. We show numerically, for both noninteracting and interacting setups, that a system coupled to a single bath exhibits a thermal fixed point at the level of the embedding. This allows us to use various results from the thermodynamics of quantum dynamical semigroups to infer the nonequilibrium thermodynamics of the strongly coupled, non-Markovian central systems. In particular, we show that the entropy production in the transient regime recovers the well-established microscopic definitions of entropy production with a correction that can be computed explicitly for both the single- and multiple-lead cases.

2.
Nat Commun ; 15(1): 7567, 2024 Aug 31.
Article de Anglais | MEDLINE | ID: mdl-39217176

RÉSUMÉ

Ageing is the accumulation of changes and decline of function of organisms over time. The concept and biomarkers of biological age have been established, notably DNA methylation-based clocks. The emergence of single-cell DNA methylation profiling methods opens the possibility of studying the biological age of individual cells. Here, we generate a large single-cell DNA methylation and transcriptome dataset from mouse peripheral blood samples, spanning a broad range of ages. The number of genes expressed increases with age, but gene-specific changes are small. We next develop scEpiAge, a single-cell DNA methylation age predictor, which can accurately predict age in (very sparse) publicly available datasets, and also in single cells. DNA methylation age distribution is wider than technically expected, indicating epigenetic age heterogeneity and functional differences. Our work provides a foundation for single-cell and sparse data epigenetic age predictors, validates their functionality and highlights epigenetic heterogeneity during ageing.


Sujet(s)
Vieillissement , Méthylation de l'ADN , Épigenèse génétique , Analyse sur cellule unique , Transcriptome , Animaux , Analyse sur cellule unique/méthodes , Vieillissement/sang , Vieillissement/génétique , Souris , Vieillissement de la cellule/génétique , Mâle , Souris de lignée C57BL , Femelle , Analyse de profil d'expression de gènes/méthodes , Épigénomique/méthodes
3.
Eur J Public Health ; 2024 Jun 22.
Article de Anglais | MEDLINE | ID: mdl-38908020

RÉSUMÉ

Over the past decade, access to National Health Service (NHS) dentistry in England has been problematic. There are increasing media reports of patients being unable to find treatment at a local NHS dentist. However, the extent of this issue varies by location and by the characteristics of the neighbourhood. The study uses official data sources on NHS dental provision and population. Travel accessibility is measured using car journey times. An advanced form of Floating Catchment Area accessibility is used, which accounts for supply competition, varying catchments, and distance decay. Spatial availability and accessibility indices are calculated. Ways in which the method can be used to explore various types of 'what-if' scenarios are outlined. Both availability and accessibility vary by the level of neighbourhood deprivation and the urban/rural nature of the neighbourhood. A case study, based on a real-world situation, shows the impact on the local neighbourhood of the closure of a dental practice. For all neighbourhoods, NHS dental provision is generally less than would be needed to provide basic dental care. The interpretation of outputs needs to take account of edge-effects near to Scotland and Wales. Possible improvements include the inclusion of other modes of travel and the exclusion of the population that does not want to access NHS care.

4.
Br Dent J ; 2024 Jun 20.
Article de Anglais | MEDLINE | ID: mdl-38902438

RÉSUMÉ

Introduction There is a growing concern that the NHS's ability to deliver dental care is not keeping pace with population growth. Also, existing capacity may not be evenly distributed, potentially creating dental deserts in some neighbourhoods.Aims This study aims to explore recent trends in NHS general practice dental capacity in England and analyse if these trends vary depending on neighbourhood context.Design This research employs a descriptive analysis of time trends.Materials and methods The study uses data on NHS-contracted capacity in England, measured in units of dental activity (UDAs). These UDAs are geo-located to neighbourhood types using practice postcodes. Changes in the populations of these neighbourhoods provide context for the capacity trends.Results Some trends remain stable over time, albeit at insufficient levels. Rural areas continue to have the lowest capacity for NHS dental treatments. Additionally, areas with previously generous provision are experiencing significant percentage decreases in capacity.Discussion To prevent the formation of dental deserts, two critical issues require attention: firstly, the accessibility of NHS treatment and how it varies across urban/suburban and rural neighbourhoods; secondly, balancing supply and demand by matching the supply of dental care with the demand, conditioned by socio-economic and socio-demographic factors within different neighbourhoods.

5.
MMWR Morb Mortal Wkly Rep ; 73(22): 514-516, 2024 Jun 06.
Article de Anglais | MEDLINE | ID: mdl-38843099

RÉSUMÉ

Invasive meningococcal disease (IMD), caused by infection with the bacterium Neisseria meningitidis, usually manifests as meningitis or septicemia and can be severe and life-threatening (1). Six serogroups (A, B, C, W, X, and Y) account for most cases (2). N. meningitidis is transmitted person-to-person via respiratory droplets and oropharyngeal secretions. Asymptomatic persons can carry N. meningitidis and transmit the bacteria to others, potentially causing illness among susceptible persons. Outbreaks can occur in conjunction with large gatherings (3,4). Vaccines are available to prevent meningococcal disease. Antibiotic prophylaxis for close contacts of infected persons is critical to preventing secondary cases (2).


Sujet(s)
Infections à méningocoques , Neisseria meningitidis , Humains , Infections à méningocoques/épidémiologie , Infections à méningocoques/prévention et contrôle , États-Unis/épidémiologie , France/épidémiologie , Arabie saoudite/épidémiologie , Jeune adulte , Adulte , Adolescent , Mâle , Femelle , Neisseria meningitidis/isolement et purification , Enfant , Enfant d'âge préscolaire , Royaume-Uni/épidémiologie , Adulte d'âge moyen , Nourrisson , Sujet âgé , Maladie liée aux voyages , Épidémies de maladies/prévention et contrôle , Voyage
6.
Dev Cell ; 2024 Jun 12.
Article de Anglais | MEDLINE | ID: mdl-38889726

RÉSUMÉ

To implant in the uterus, mammalian embryos form blastocysts comprising trophectoderm (TE) surrounding an inner cell mass (ICM), confined to the polar region by the expanding blastocoel. The mode of implantation varies between species. Murine embryos maintain a single layered TE until they implant in the characteristic thick deciduum, whereas human blastocysts attach via polar TE directly to the uterine wall. Using immunofluorescence (IF) of rapidly isolated ICMs, blockade of RNA and protein synthesis in whole embryos, or 3D visualization of immunostained embryos, we provide evidence of multi-layering in human polar TE before implantation. This may be required for rapid uterine invasion to secure the developing human embryo and initiate formation of the placenta. Using sequential fluorescent labeling, we demonstrate that the majority of inner TE in human blastocysts arises from existing outer cells, with no evidence of conversion from the ICM in the context of the intact embryo.

7.
Nat Commun ; 15(1): 3734, 2024 May 03.
Article de Anglais | MEDLINE | ID: mdl-38702312

RÉSUMÉ

Mutations in DNA damage response (DDR) factors are associated with human infertility, which affects up to 15% of the population. The DDR is required during germ cell development and meiosis. One pathway implicated in human fertility is DNA translesion synthesis (TLS), which allows replication impediments to be bypassed. We find that TLS is essential for pre-meiotic germ cell development in the embryo. Loss of the central TLS component, REV1, significantly inhibits the induction of human PGC-like cells (hPGCLCs). This is recapitulated in mice, where deficiencies in TLS initiation (Rev1-/- or PcnaK164R/K164R) or extension (Rev7 -/-) result in a > 150-fold reduction in the number of primordial germ cells (PGCs) and complete sterility. In contrast, the absence of TLS does not impact the growth, function, or homeostasis of somatic tissues. Surprisingly, we find a complete failure in both activation of the germ cell transcriptional program and in DNA demethylation, a critical step in germline epigenetic reprogramming. Our findings show that for normal fertility, DNA repair is required not only for meiotic recombination but for progression through the earliest stages of germ cell development in mammals.


Sujet(s)
Déméthylation de l'ADN , Réparation de l'ADN , DNA-directed DNA polymerase , Cellules germinales , Animaux , Femelle , Humains , Mâle , Souris , Altération de l'ADN , DNA-directed DNA polymerase/métabolisme , DNA-directed DNA polymerase/génétique , Épigenèse génétique , Cellules germinales/métabolisme , Méiose/génétique , Souris knockout , Nucleotidyltransferases/métabolisme , Nucleotidyltransferases/génétique , Antigène nucléaire de prolifération cellulaire/métabolisme ,
8.
Emerg Infect Dis ; 30(5): 1009-1012, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38666632

RÉSUMÉ

We report a cluster of serogroup B invasive meningococcal disease identified via genomic surveillance in older adults in England and describe the public health responses. Genomic surveillance is critical for supporting public health investigations and detecting the growing threat of serogroup B Neisseria meningitidis infections in older adults.


Sujet(s)
Infections à méningocoques , Neisseria meningitidis sérogroupe B , Humains , Angleterre/épidémiologie , Sujet âgé , Infections à méningocoques/épidémiologie , Infections à méningocoques/microbiologie , Neisseria meningitidis sérogroupe B/génétique , Neisseria meningitidis sérogroupe B/isolement et purification , Mâle , Sujet âgé de 80 ans ou plus , Génomique/méthodes , Femelle , Histoire du 21ème siècle , Génome bactérien , Adulte d'âge moyen
9.
J Pediatr Intensive Care ; 13(1): 32-36, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38571979

RÉSUMÉ

Percutaneous pericardiocentesis remains a challenging and potentially dangerous procedure, particularly in small, critically ill patients. We present outcomes of the PLANE (pericardiocentesis using long-axis in-plane real-time echocardiography) technique for pediatric pericardiocentesis compared with a standard echocardiography (ECHO) guidance cohort. This was a retrospective chart review of all children undergoing percutaneous pericardiocentesis from March 2013 to February 2021 at a single center. A total of 78 procedures were performed, 52 utilizing PLANE technique and 26 utilizing standard ECHO-guidance technique. There was 100% technical success rate with only one minor complication for the entire cohort. Procedures were evenly split between the bedside intensive care unit and cardiac catheterization laboratory. PLANE technique was utilized in significantly younger (1.4 vs. 8.4 years, p = 0.008) and smaller (11.1 vs. 31.8 kg, p = 0.007) patients, as well as in most patients deemed high risk (postoperative < 7 days, extracorporeal membrane oxygenation (ECMO) support, and/or weight less than 5 kg; 19/22, p = 0.021). Other patient characteristics were similar between the two groups. There was a trend toward PLANE technique utilization by noncardiology trained operators. The PLANE technique for pediatric pericardiocentesis is safe and effective and can be effectively utilized in small and high-risk patient populations. The technical similarity to other long-axis ultrasound-guided procedures may facilitate adoption and mastery by critical care trained operators.

10.
J Cardiothorac Surg ; 19(1): 94, 2024 Feb 14.
Article de Anglais | MEDLINE | ID: mdl-38355499

RÉSUMÉ

When technical requirements are high, and patient outcomes are critical, opportunities for monitoring and improving surgical skills via objective motion analysis feedback may be particularly beneficial. This narrative review synthesises work on technical and non-technical surgical skills, collaborative task performance, and pose estimation to illustrate new opportunities to advance cardiothoracic surgical performance with innovations from computer vision and artificial intelligence. These technological innovations are critically evaluated in terms of the benefits they could offer the cardiothoracic surgical community, and any barriers to the uptake of the technology are elaborated upon. Like some other specialities, cardiothoracic surgery has relatively few opportunities to benefit from tools with data capture technology embedded within them (as is possible with robotic-assisted laparoscopic surgery, for example). In such cases, pose estimation techniques that allow for movement tracking across a conventional operating field without using specialist equipment or markers offer considerable potential. With video data from either simulated or real surgical procedures, these tools can (1) provide insight into the development of expertise and surgical performance over a surgeon's career, (2) provide feedback to trainee surgeons regarding areas for improvement, (3) provide the opportunity to investigate what aspects of skill may be linked to patient outcomes which can (4) inform the aspects of surgical skill which should be focused on within training or mentoring programmes. Classifier or assessment algorithms that use artificial intelligence to 'learn' what expertise is from expert surgical evaluators could further assist educators in determining if trainees meet competency thresholds. With collaborative efforts between surgical teams, medical institutions, computer scientists and researchers to ensure this technology is developed with usability and ethics in mind, the developed feedback tools could improve cardiothoracic surgical practice in a data-driven way.


Sujet(s)
Laparoscopie , Interventions chirurgicales robotisées , Humains , Intelligence artificielle , Analyse et exécution des tâches , Ordinateurs , Compétence clinique
11.
mBio ; : e0171223, 2023 Nov 09.
Article de Anglais | MEDLINE | ID: mdl-37943059

RÉSUMÉ

The COVID-19 pandemic demonstrated the poor ability of body temperature to reliably identify SARS-CoV-2-infected individuals, an observation that has been made before in the context of other infectious diseases. While acute infection does not always cause fever, it does reliably drive host transcriptional responses as the body responds at the site of infection. These transcriptional changes can occur both in cells that are directly harboring replicating pathogens and in cells elsewhere that receive a molecular signal that infection is occurring. Here, we identify a core set of approximately 70 human genes that are together upregulated in cultured human cells infected by a broad array of viral, bacterial, and fungal pathogens. We have named these "core response" genes. In theory, transcripts from these genes could serve as biomarkers of infection in the human body, in a way that is agnostic to the specific pathogen causing infection. As such, we perform human studies to show that these infection-induced human transcripts can be measured in the saliva of people harboring different types of infections. The number of these transcripts in saliva can correctly classify infection status (whether a person harbors an infection) 91% of the time. Furthermore, in the case of SARS-CoV-2 specifically, the number of core response transcripts in saliva correctly identifies infectious individuals even when enrollees, themselves, are asymptomatic and do not know they are infected.IMPORTANCEThere are a variety of clinical and laboratory criteria available to clinicians in controlled healthcare settings to help them identify whether an infectious disease is present. However, in situations such as a new epidemic caused by an unknown infectious agent, in health screening contexts performed within communities and outside of healthcare facilities or in battlefield or potential biowarfare situations, this gets more difficult. Pathogen-agnostic methods for rapid screening and triage of large numbers of people for infection status are needed, in particular methods that might work on an easily accessible biospecimen like saliva. Here, we identify a small, core set of approximately 70 human genes whose transcripts serve as saliva-based biomarkers of infection in the human body, in a way that is agnostic to the specific pathogen causing infection.

12.
Ecotoxicol Environ Saf ; 268: 115718, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-38000305

RÉSUMÉ

Chronic toxicity tests on adult and larval honey bees (Apis mellifera) can require the use of dietary additives (solvents, emulsifiers, adjuvants and viscosifier agents) when the active ingredient of plant protection products cannot be dissolved or does not remain stable and homogeneous within the test diets. Acetone is the widely used and accepted solvent allowed within the international regulatory guidelines, but it can be ineffective in keeping certain compounds in solution and can cause toxicity to adults and larvae. In this publication, we present an evaluation of alternative additives in adult and larval diets. Six dietary additives including five solvents (ethanol, isopropanol, n-propanol, propylene glycol and triethylene glycol) and a viscosifier agent (xanthan gum) at five concentrations along with a negative control and a solvent control (acetone) were investigated at seven laboratories. The safe levels for bees were determined for each of the additives used in the 10-day chronic adult and 22-day chronic larval tests. In the 10-day chronic adult study, ethanol and isopropanol were found to be safe at concentrations ≤ 5.0 %, while xanthan gum can be reliably used at concentrations ≤ 0.1 %. Greater variability across laboratories was observed for N-propanol, propylene glycol, and triethylene glycol and these agents may cause mortality when added to diets at concentrations above 0.25-0.5 %. The safe levels of additives to larval diet in the 22-day chronic larval test had a greater variability and were generally lower than what were observed for adult diet. Our results do not recommend the inclusion of ethanol or n-propanol into the larval diet, and isopropanol, propylene glycol, and triethylene glycol may cause mortality at concentrations above 0.25-0.5 %. Safe levels for xanthan gum were more variable than what was observed for adults, but it can be used reliably at concentrations ≤ 0.05 %. Our analyses conclude that several additives can be integrated successfully in honey bee laboratory bioassays at levels that cause low mortality to adults and larvae.


Sujet(s)
Propan-2-ol , Acétone , Abeilles , Animaux , Larve , Propan-1-ol , Laboratoires , Régime alimentaire , Solvants , Éthanol , Propylène glycols
13.
J Infect ; 87(6): 479-489, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-37797844

RÉSUMÉ

OBJECTIVE: Few data outside of individual case reports are available on non-meningococcal, non-gonococcal species of Neisseria as causative agents of invasive disease. This review collates disease, organism and patient information from case reports on the topic. METHODS: A literature search was performed examining articles describing diseases caused by non-meningococcal and non-gonococcal Neisseria. FINDINGS: Neisseria present as opportunistic pathogens causing a wide variety of diseases including serious presentations, endocarditis being the most common condition described and N. mucosa the most commonly presenting pathogen overall. Disease may occur in otherwise healthy patients, although risk factors for infection include recent surgery, an immunocompromised state, poor oral health, and intravenous drug use. CONCLUSIONS: Commensal Neisseria infections are rare but can present serious invasive diseases. Further research is required to determine why some species cause disease more than others or why some are inclined towards particular manifestations.


Sujet(s)
Endocardite , Neisseria meningitidis , Humains , Neisseria , Symbiose , Sujet immunodéprimé
14.
J Hand Surg Eur Vol ; : 17531934231196421, 2023 Sep 11.
Article de Anglais | MEDLINE | ID: mdl-37694876

RÉSUMÉ

The present study analyses the relationships between deprivation and obstetric brachial plexus palsy (OBPP). A retrospective observational study was conducted of infants with OBPP seen between 2008 and 2020 (n = 321). The index of multiple deprivation (IMD) was used to assign an IMD rank to patients based on birth postcode and the relationship with OBPP was analysed, including deprivation, gestational diabetes, age at referral and at first assessment. Quintile-based analysis demonstrated over-representation of patients from more deprived neighbourhoods (n = 109, 39%) living in the top 20% most deprived neighbourhoods. A total of 48 (15%) mothers had diabetes and 98 (31%) infants underwent surgical brachial plexus exploration (a marker of disease severity). Neither diabetes, age at referral nor age at first assessment were associated with IMD score. This suggests that neighbourhood deprivation is associated with OBPP, though the mechanisms are unclear. Further studies in this area may enable targeted health intervention for more deprived maternal and infant groups.Level of evidence: III.

15.
J Infect ; 87(5): 385-391, 2023 Nov.
Article de Anglais | MEDLINE | ID: mdl-37689395

RÉSUMÉ

OBJECTIVES: In 2020, COVID-19 pandemic restrictions led to a major suppression of meningococcal disease in England. Here we describe the epidemiology of invasive meningococcal disease in the three years prior to the COVID-19 pandemic, and the three years immediately after the introduction of restrictions. METHODS: The UK Health Security Agency conducts national meningococcal disease surveillance in England consisting of laboratory-based case confirmation with strain characterisation by culture and/or molecular detection, as well as clinical follow-up of all cases. RESULTS: In the pre-pandemic period, 554-742 IMD cases were laboratory-confirmed per year. MenB caused 57.2% of cases, followed by MenW (22.7%), MenY (10.6%) and MenC (7.7%). The introduction of restrictions in late March 2020 led to a 73% reduction in IMD. After the removal of restrictions in 2021, a resurgence in MenB was observed, primarily in teenagers and young adults. During the following winter period (2022/23), MenB disease increased to the highest level since 2012 with cases rising across multiple age groups, however, cases in young children eligible for MenB vaccination remained lower than prior to the pandemic. MenACWY cases remained very low throughout the pandemic period. CONCLUSIONS: Once pandemic restrictions in England were removed, MenB quickly rebounded- initially driven by a resurgence in teenagers/young adults, but later among other age groups. MenACWY cases remain very low due to the protection afforded by the adolescent MenACWY conjugate vaccine programme.

16.
Innovations (Phila) ; 18(5): 494-497, 2023.
Article de Anglais | MEDLINE | ID: mdl-37610181

RÉSUMÉ

Trapped prosthetic valve leaflets are a rare but challenging complication. A 68-year-old male patient had previously undergone redo aortic valve replacement. Postoperatively, he decompensated with severe mitral regurgitation, requiring extracorporeal membrane oxygenation and a salvage mitral valve replacement via right thoracotomy with very difficult access. This procedure was complicated by a trapped valve leaflet. He recovered well initially but presented 2 years later with worsening heart failure due to mitral stenosis and rising pulmonary artery pressures. Due to the high risk of sternotomy and right thoracotomy, a transventricular cardioscopic release of the trapped mitral valve leaflet was undertaken by left minithoracotomy. The procedure was successful, and the patient was discharged home on day 12. This novel minimally invasive approach, which does not require myocardial preservation, is ideal for high-risk patients with this rare complication and has not previously been described. We hope that by sharing our experience, others will consider this innovative approach.

17.
Thorax ; 78(12): 1206-1214, 2023 12.
Article de Anglais | MEDLINE | ID: mdl-37487710

RÉSUMÉ

INTRODUCTION: A new UK Lung Allocation Scheme (UKLAS) was introduced in 2017, replacing the previous geographic allocation system. Patients are prioritised according to predefined clinical criteria into a three-tier system: the super-urgent lung allocation scheme (SULAS), the urgent lung allocation scheme (ULAS) and the non-urgent lung allocation scheme (NULAS). This study assessed the early impact of this scheme on waiting-list and post-transplant outcomes. METHODS: A cohort study of adult lung transplant registrations between March 2015 and November 2016 (era-1) and between May 2017 and January 2019 (era-2). Outcomes from registration were compared between eras and stratified by urgency tier and diagnostic group. RESULTS: During era-1, 461 patients were registered. In era-2, 471 patients were registered (19 (4.0%) SULAS, 82 (17.4%) ULAS and 370 (78.6%) NULAS). SULAS patients were younger (median age 35 vs 50 and 55 for urgent and non-urgent, respectively, p=0.0015) and predominantly suffered from cystic fibrosis (53%) or pulmonary fibrosis (37%). Between eras 1 and 2, the odds of transplantation within 6 months of registration were increased (OR=1.41, 95% CI 1.07 to 1.85, p=0.0142) despite only a 5% increase in transplant activity. Median time-to-transplantation during era-1 was 427 days compared with waiting times in era-2 of 8 days for SULAS, 15 days for ULAS and 585 days for NULAS patients. Waiting-list mortality (15% era-1 vs 13% era-2; p=0.5441) and post-transplant survival at 1 year (81.3% era-1 vs 83.3% era-2; p=0.6065) were similar between eras. CONCLUSION: The UKLAS scheme prioritises the critically ill and improves transplantation odds. The true impact on waiting-list mortality and post-transplant survival requires further follow-up.


Sujet(s)
Mucoviscidose , Transplantation pulmonaire , Adulte , Humains , Études de cohortes , Poumon , Royaume-Uni/épidémiologie , Études rétrospectives
18.
J Heart Lung Transplant ; 42(10): 1378-1396, 2023 10.
Article de Anglais | MEDLINE | ID: mdl-37127072

RÉSUMÉ

BACKGROUND: Some degree of ischemia is inevitable in organ transplantation, and for most, if not all organs, there is a relationship between ischemic time and transplant outcome. The contribution of ischemic time to lung injury is unclear, with conflicting recent data. In this study, we investigate the impact of ischemia time on survival after lung transplantation in a large national cohort. METHODS: We studied the outcomes for 1,565 UK adult lung transplants over a 12-year period, for whom donor, transplant, and recipient data were available from the UK Transplant Registry. We examined the effect of ischemia time (defined as donor cross-clamp to recipient reperfusion) and whether standard cardiopulmonary bypass was used using Cox proportional hazards models, adjusting for other risk factors. RESULTS: The total ischemic time increased from a median under 5 hours in 2003 to over 6.2 hours in 2013. Our findings show that, when the cardiopulmonary bypass was used, there was an increase in the hazard of death (of 13% [95% CI: 5%-21%] for 1-year patient survival) for each hour of total ischemic time. However, if the cardiopulmonary bypass was not used for implantation, this link disappeared-there was no statistically significant change in mortality with increasing ischemic time. CONCLUSIONS: We document that avoidance of bypass may remove ischemic time, within the limits of our observed range of ischemic times, as a risk factor for poor outcomes. Our data add to the evidence that bypass may be harmful to the donor lung.


Sujet(s)
Pontage cardiopulmonaire , Transplantation pulmonaire , Adulte , Humains , Facteurs temps , Ischémie , Royaume-Uni/épidémiologie , Donneurs de tissus , Études rétrospectives
19.
J Heart Lung Transplant ; 42(8): 1120-1130, 2023 08.
Article de Anglais | MEDLINE | ID: mdl-37032222

RÉSUMÉ

BACKGROUND: The United Kingdom (UK) was one of the first countries to pioneer heart transplantation from donation after circulatory death (DCD) donors. To facilitate equity of access to DCD hearts by all UK heart transplant centers and expand the retrieval zone nationwide, a Joint Innovation Fund (JIF) pilot was provided by NHS Blood and Transplant (NHSBT) and NHS England (NHSE). The activity and outcomes of this national DCD heart pilot program are reported. METHODS: This is a national multi-center, retrospective cohort study examining early outcomes of DCD heart transplants performed across 7 heart transplant centers, adult and pediatric, throughout the UK. Hearts were retrieved using the direct procurement and perfusion (DPP) technique by 3 specialist retrieval teams trained in ex-situ normothermic machine perfusion. Outcomes were compared against DCD heart transplants before the national pilot era and against contemporaneous donation after brain death (DBD) heart transplants, and analyzed using Kaplan-Meier analysis, chi-square test, and Wilcoxon's rank-sum. RESULTS: From September 7, 2020 to February 28, 2022, 215 potential DCD hearts were offered of which 98 (46%) were accepted and attended. There were 77 potential donors (36%) which proceeded to death within 2 hours, with 57 (27%) donor hearts successfully retrieved and perfused ex situ and 50 (23%) DCD hearts going on to be transplanted. During this same period, 179 DBD hearts were transplanted. Overall, there was no difference in the 30-day survival rate between DCD and DBD (94% vs 93%) or 90 day survival (90% vs 90%) respectively. There was a higher rate of ECMO use post-DCD heart transplants compared to DBD (40% vs 16%, p = 0.0006), and DCD hearts in the pre pilot era, (17%, p = 0.002). There was no difference in length of ICU stay (9 DCD vs 8 days DBD, p = 0.13) nor hospital stay (28 DCD vs 27 DBD days, p = 0.46). CONCLUSION: During this pilot study, 3 specialist retrieval teams were able to retrieve DCD hearts nationally for all 7 UK heart transplant centers. DCD donors increased overall heart transplantation in the UK by 28% with equivalent early posttransplant survival compared with DBD donors.


Sujet(s)
Transplantation cardiaque , Acquisition d'organes et de tissus , Adulte , Humains , Enfant , Donneurs de tissus , Études rétrospectives , Projets pilotes , Mort cérébrale , Royaume-Uni/épidémiologie , Survie du greffon , Mort
20.
Elife ; 122023 03 20.
Article de Anglais | MEDLINE | ID: mdl-36940244

RÉSUMÉ

The gill skeleton of cartilaginous fishes (sharks, skates, rays, and holocephalans) exhibits a striking anterior-posterior polarity, with a series of fine appendages called branchial rays projecting from the posterior margin of the gill arch cartilages. We previously demonstrated in the skate (Leucoraja erinacea) that branchial rays derive from a posterior domain of pharyngeal arch mesenchyme that is responsive to Sonic hedgehog (Shh) signaling from a distal gill arch epithelial ridge (GAER) signaling centre. However, how branchial ray progenitors are specified exclusively within posterior gill arch mesenchyme is not known. Here, we show that genes encoding several Wnt ligands are expressed in the ectoderm immediately adjacent to the skate GAER, and that these Wnt signals are transduced largely in the anterior arch environment. Using pharmacological manipulation, we show that inhibition of Wnt signalling results in an anterior expansion of Shh signal transduction in developing skate gill arches, and in the formation of ectopic anterior branchial ray cartilages. Our findings demonstrate that ectodermal Wnt signalling contributes to gill arch skeletal polarity in skate by restricting Shh signal transduction and chondrogenesis to the posterior arch environment and highlights the importance of signalling interactions at embryonic tissue boundaries for cell fate determination in vertebrate pharyngeal arches.


Sujet(s)
Région branchiale , Rajidae , Animaux , Voie de signalisation Wnt , Protéines Hedgehog/génétique , Ectoderme , Branchies , Squelette
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