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1.
Nat Immunol ; 24(12): 2091-2107, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37945820

RESUMO

Regulatory T (Treg) cell modulation of adaptive immunity and tissue homeostasis is well described; however, less is known about Treg cell-mediated regulation of the innate immune response. Here we show that deletion of ST2, the receptor for interleukin (IL)-33, on Treg cells increased granulocyte influx into the lung and increased cytokine production by innate lymphoid and γδ T cells without alteration of adaptive immunity to influenza. IL-33 induced high levels of the interleukin-1 receptor antagonist (IL-1Ra) in ST2+ Treg cells and deletion of IL-1Ra in Treg cells increased granulocyte influx into the lung. Treg cell-specific deletion of ST2 or IL-1Ra improved survival to influenza, which was dependent on IL-1. Adventitial fibroblasts in the lung expressed high levels of the IL-1 receptor and their chemokine production was suppressed by Treg cell-produced IL-1Ra. Thus, we define a new pathway where IL-33-induced IL-1Ra production by tissue Treg cells suppresses IL-1-mediated innate immune responses to respiratory viral infection.


Assuntos
Influenza Humana , Linfócitos T Reguladores , Humanos , Imunidade Inata , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1/genética , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Interleucina-33/metabolismo , Linfócitos/metabolismo , Animais , Camundongos
2.
Nat Immunol ; 21(11): 1371-1383, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32989331

RESUMO

Foxp3+ regulatory T (Treg) cells expressing the interleukin (IL)-33 receptor ST2 mediate tissue repair in response to IL-33. Whether Treg cells also respond to the alarmin IL-33 to regulate specific aspects of the immune response is not known. Here we describe an unexpected function of ST2+ Treg cells in suppressing the innate immune response in the lung to environmental allergens without altering the adaptive immune response. Following allergen exposure, ST2+ Treg cells were activated by IL-33 to suppress IL-17-producing γδ T cells. ST2 signaling in Treg cells induced Ebi3, a component of the heterodimeric cytokine IL-35 that was required for Treg cell-mediated suppression of γδ T cells. This response resulted in fewer eosinophil-attracting chemokines and reduced eosinophil recruitment into the lung, which was beneficial to the host in reducing allergen-induced inflammation. Thus, we define a fundamental role for ST2+ Treg cells in the lung as a negative regulator of the early innate γδ T cell response to mucosal injury.


Assuntos
Imunomodulação , Interleucina-33/metabolismo , Linfócitos Intraepiteliais/imunologia , Linfócitos Intraepiteliais/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Alérgenos/imunologia , Animais , Biomarcadores , Imunofenotipagem , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Leucócitos/imunologia , Leucócitos/metabolismo , Camundongos
3.
Genes Dev ; 38(1-2): 46-69, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38286657

RESUMO

Approximately 20% of head and neck squamous cell carcinomas (HNSCCs) exhibit reduced methylation on lysine 36 of histone H3 (H3K36me) due to mutations in histone methylase NSD1 or a lysine-to-methionine mutation in histone H3 (H3K36M). Whether such alterations of H3K36me can be exploited for therapeutic interventions is still unknown. Here, we show that HNSCC models expressing H3K36M can be divided into two groups: those that display aberrant accumulation of H3K27me3 and those that maintain steady levels of H3K27me3. The former group exhibits reduced proliferation, genome instability, and heightened sensitivity to genotoxic agents like PARP1/2 inhibitors. Conversely, H3K36M HNSCC models with constant H3K27me3 levels lack these characteristics unless H3K27me3 is elevated by DNA hypomethylating agents or inhibiting H3K27me3 demethylases KDM6A/B. Mechanistically, H3K36M reduces H3K36me by directly impeding the activities of the histone methyltransferase NSD3 and the histone demethylase LSD2. Notably, aberrant H3K27me3 levels induced by H3K36M expression are not a bona fide epigenetic mark because they require continuous expression of H3K36M to be inherited. Moreover, increased sensitivity to PARP1/2 inhibitors in H3K36M HNSCC models depends solely on elevated H3K27me3 levels and diminishing BRCA1- and FANCD2-dependent DNA repair. Finally, a PARP1/2 inhibitor alone reduces tumor burden in a H3K36M HNSCC xenograft model with elevated H3K27me3, whereas in a model with consistent H3K27me3, a combination of PARP1/2 inhibitors and agents that up-regulate H3K27me3 proves to be successful. These findings underscore the crucial balance between H3K36 and H3K27 methylation in maintaining genome instability, offering new therapeutic options for patients with H3K36me-deficient tumors.


Assuntos
Neoplasias de Cabeça e Pescoço , Histonas , Humanos , Histonas/metabolismo , Lisina/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Metilação , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Instabilidade Genômica/genética
4.
Nature ; 622(7982): 329-338, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37794186

RESUMO

The Pharma Proteomics Project is a precompetitive biopharmaceutical consortium characterizing the plasma proteomic profiles of 54,219 UK Biobank participants. Here we provide a detailed summary of this initiative, including technical and biological validations, insights into proteomic disease signatures, and prediction modelling for various demographic and health indicators. We present comprehensive protein quantitative trait locus (pQTL) mapping of 2,923 proteins that identifies 14,287 primary genetic associations, of which 81% are previously undescribed, alongside ancestry-specific pQTL mapping in non-European individuals. The study provides an updated characterization of the genetic architecture of the plasma proteome, contextualized with projected pQTL discovery rates as sample sizes and proteomic assay coverages increase over time. We offer extensive insights into trans pQTLs across multiple biological domains, highlight genetic influences on ligand-receptor interactions and pathway perturbations across a diverse collection of cytokines and complement networks, and illustrate long-range epistatic effects of ABO blood group and FUT2 secretor status on proteins with gastrointestinal tissue-enriched expression. We demonstrate the utility of these data for drug discovery by extending the genetic proxied effects of protein targets, such as PCSK9, on additional endpoints, and disentangle specific genes and proteins perturbed at loci associated with COVID-19 susceptibility. This public-private partnership provides the scientific community with an open-access proteomics resource of considerable breadth and depth to help to elucidate the biological mechanisms underlying proteo-genomic discoveries and accelerate the development of biomarkers, predictive models and therapeutics1.


Assuntos
Bancos de Espécimes Biológicos , Proteínas Sanguíneas , Bases de Dados Factuais , Genômica , Saúde , Proteoma , Proteômica , Humanos , Sistema ABO de Grupos Sanguíneos/genética , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/genética , COVID-19/genética , Descoberta de Drogas , Epistasia Genética , Fucosiltransferases/metabolismo , Predisposição Genética para Doença , Plasma/química , Pró-Proteína Convertase 9/metabolismo , Proteoma/análise , Proteoma/genética , Parcerias Público-Privadas , Locos de Características Quantitativas , Reino Unido , Galactosídeo 2-alfa-L-Fucosiltransferase
5.
Nature ; 609(7928): 689-694, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36071166

RESUMO

Optical atomic clocks are our most precise tools to measure time and frequency1-3. Precision frequency comparisons between clocks in separate locations enable one to probe the space-time variation of fundamental constants4,5 and the properties of dark matter6,7, to perform geodesy8-10 and to evaluate systematic clock shifts. Measurements on independent systems are limited by the standard quantum limit; measurements on entangled systems can surpass the standard quantum limit to reach the ultimate precision allowed by quantum theory-the Heisenberg limit. Although local entangling operations have demonstrated this enhancement at microscopic distances11-16, comparisons between remote atomic clocks require the rapid generation of high-fidelity entanglement between systems that have no intrinsic interactions. Here we report the use of a photonic link17,18 to entangle two 88Sr+ ions separated by a macroscopic distance19 (approximately 2 m) to demonstrate an elementary quantum network of entangled optical clocks. For frequency comparisons between the ions, we find that entanglement reduces the measurement uncertainty by nearly [Formula: see text], the value predicted for the Heisenberg limit. Today's optical clocks are typically limited by dephasing of the probe laser20; in this regime, we find that entanglement yields a factor of 2 reduction in the measurement uncertainty compared with conventional correlation spectroscopy techniques20-22. We demonstrate this enhancement for the measurement of a frequency shift applied to one of the clocks. This two-node network could be extended to additional nodes23, to other species of trapped particles or-through local operations-to larger entangled systems.

6.
Nature ; 607(7920): 682-686, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35896644

RESUMO

Cryptographic key exchange protocols traditionally rely on computational conjectures such as the hardness of prime factorization1 to provide security against eavesdropping attacks. Remarkably, quantum key distribution protocols such as the Bennett-Brassard scheme2 provide information-theoretic security against such attacks, a much stronger form of security unreachable by classical means. However, quantum protocols realized so far are subject to a new class of attacks exploiting a mismatch between the quantum states or measurements implemented and their theoretical modelling, as demonstrated in numerous experiments3-6. Here we present the experimental realization of a complete quantum key distribution protocol immune to these vulnerabilities, following Ekert's pioneering proposal7 to use entanglement to bound an adversary's information from Bell's theorem8. By combining theoretical developments with an improved optical fibre link generating entanglement between two trapped-ion qubits, we obtain 95,628 key bits with device-independent security9-12 from 1.5 million Bell pairs created during eight hours of run time. We take steps to ensure that information on the measurement results is inaccessible to an eavesdropper. These measurements are performed without space-like separation. Our result shows that provably secure cryptography under general assumptions is possible with real-world devices, and paves the way for further quantum information applications based on the device-independence principle.

7.
Nature ; 612(7938): 116-122, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36289333

RESUMO

Most animals have compound eyes, with tens to thousands of lenses attached rigidly to the exoskeleton. A natural assumption is that all of these species must resort to moving either their head or their body to actively change their visual input. However, classic anatomy has revealed that flies have muscles poised to move their retinas under the stable lenses of each compound eye1-3. Here we show that Drosophila use their retinal muscles to smoothly track visual motion, which helps to stabilize the retinal image, and also to perform small saccades when viewing a stationary scene. We show that when the retina moves, visual receptive fields shift accordingly, and that even the smallest retinal saccades activate visual neurons. Using a head-fixed behavioural paradigm, we find that Drosophila perform binocular, vergence movements of their retinas-which could enhance depth perception-when crossing gaps, and impairing the physiology of retinal motor neurons alters gap-crossing trajectories during free behaviour. That flies evolved an ability to actuate their retinas suggests that moving the eye independently of the head is broadly paramount for animals. The similarities of smooth and saccadic movements of the Drosophila retina and the vertebrate eye highlight a notable example of convergent evolution.


Assuntos
Drosophila , Movimentos Oculares , Músculos , Retina , Visão Ocular , Animais , Drosophila/fisiologia , Movimentos Oculares/fisiologia , Músculos/fisiologia , Retina/fisiologia , Movimentos Sacádicos/fisiologia , Visão Ocular/fisiologia , Visão Binocular , Percepção de Profundidade , Neurônios Motores , Cabeça/fisiologia , Drosophila melanogaster/fisiologia , Evolução Biológica
8.
Semin Cell Dev Biol ; 144: 11-19, 2023 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-36202693

RESUMO

The world population's life expectancy is growing, and neurodegenerative disorders common in old age require more efficient therapies. In this context, neural stem cells (NSCs) are imperative for the development and maintenance of the functioning of the nervous system and have broad therapeutic applicability for neurodegenerative diseases. Therefore, knowing all the mechanisms that govern the self-renewal, differentiation, and cell signaling of NSC is necessary. This review will address some of these aspects, including the role of growth and transcription factors, epigenetic modulators, microRNAs, and extracellular matrix components. Furthermore, differentiation and transdifferentiation processes will be addressed as therapeutic strategies showing their significance for stem cell-based therapy.


Assuntos
MicroRNAs , Células-Tronco Neurais , Diferenciação Celular , Neurogênese/fisiologia , Neurônios , MicroRNAs/genética
9.
J Biol Chem ; 300(3): 105732, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336290

RESUMO

The manganese (Mn) export protein SLC30A10 is essential for Mn excretion via the liver and intestines. Patients with SLC30A10 deficiency develop Mn excess, dystonia, liver disease, and polycythemia. Recent genome-wide association studies revealed a link between the SLC30A10 variant T95I and markers of liver disease. The in vivo relevance of this variant has yet to be investigated. Using in vitro and in vivo models, we explore the impact of the T95I variant on SLC30A10 function. While SLC30A10 I95 expressed at lower levels than T95 in transfected cell lines, both T95 and I95 variants protected cells similarly from Mn-induced toxicity. Adeno-associated virus 8-mediated expression of T95 or I95 SLC30A10 using the liver-specific thyroxine binding globulin promoter normalized liver Mn levels in mice with hepatocyte Slc30a10 deficiency. Furthermore, Adeno-associated virus-mediated expression of T95 or I95 SLC30A10 normalized red blood cell parameters and body weights and attenuated Mn levels and differential gene expression in livers and brains of mice with whole body Slc30a10 deficiency. While our in vivo data do not indicate that the T95I variant significantly compromises SLC30A10 function, it does reinforce the notion that the liver is a key site of SLC30A10 function. It also supports the idea that restoration of hepatic SLC30A10 expression is sufficient to attenuate phenotypes in SLC30A10 deficiency.


Assuntos
Substituição de Aminoácidos , Proteínas de Transporte de Cátions , Dependovirus , Fígado , Manganês , Mutação , Animais , Camundongos , Peso Corporal , Encéfalo/metabolismo , Proteínas de Transporte de Cátions/deficiência , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Linhagem Celular , Dependovirus/genética , Eritrócitos , Estudo de Associação Genômica Ampla , Hepatócitos/metabolismo , Fígado/citologia , Fígado/metabolismo , Hepatopatias/genética , Hepatopatias/metabolismo , Manganês/metabolismo , Intoxicação por Manganês/metabolismo , Fenótipo , Regiões Promotoras Genéticas , Globulina de Ligação a Tiroxina/genética
10.
Cell ; 143(2): 212-24, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20888037

RESUMO

Chromatin is important for the regulation of transcription and other functions, yet the diversity of chromatin composition and the distribution along chromosomes are still poorly characterized. By integrative analysis of genome-wide binding maps of 53 broadly selected chromatin components in Drosophila cells, we show that the genome is segmented into five principal chromatin types that are defined by unique yet overlapping combinations of proteins and form domains that can extend over > 100 kb. We identify a repressive chromatin type that covers about half of the genome and lacks classic heterochromatin markers. Furthermore, transcriptionally active euchromatin consists of two types that differ in molecular organization and H3K36 methylation and regulate distinct classes of genes. Finally, we provide evidence that the different chromatin types help to target DNA-binding factors to specific genomic regions. These results provide a global view of chromatin diversity and domain organization in a metazoan cell.


Assuntos
Cromatina/classificação , Proteínas de Ligação a DNA/análise , Proteínas de Drosophila/análise , Drosophila melanogaster/genética , Animais , Linhagem Celular , Cromatina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Eucromatina/metabolismo , Heterocromatina/metabolismo , Histonas/metabolismo , Análise de Componente Principal
11.
PLoS Genet ; 18(9): e1010200, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36074769

RESUMO

SARS-CoV-2 whole genome sequencing has played an important role in documenting the emergence of polymorphisms in the viral genome and its continuing evolution during the COVID-19 pandemic. Here we present data from over 360 patients to characterize the complex sequence diversity of individual infections identified during multiple variant surges (e.g., Alpha and Delta). Across our survey, we observed significantly increasing SARS-CoV-2 sequence diversity during the pandemic and frequent occurrence of multiple biallelic sequence polymorphisms in all infections. This sequence polymorphism shows that SARS-CoV-2 infections are heterogeneous mixtures. Convention for reporting microbial pathogens guides investigators to report a majority consensus sequence. In our study, we found that this approach would under-report sequence variation in all samples tested. As we find that this sequence heterogeneity is efficiently transmitted from donors to recipients, our findings illustrate that infection complexity must be monitored and reported more completely to understand SARS-CoV-2 infection and transmission dynamics. Many of the nucleotide changes that would not be reported in a majority consensus sequence have now been observed as lineage defining SNPs in Omicron BA.1 and/or BA.2 variants. This suggests that minority alleles in earlier SARS-CoV-2 infections may play an important role in the continuing evolution of new variants of concern.


Assuntos
COVID-19 , COVID-19/genética , Genoma Viral/genética , Humanos , Pandemias , SARS-CoV-2/genética
12.
Am J Transplant ; 24(7): 1267-1278, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38431077

RESUMO

Pediatric heart failure and transplantation carry associated risks for kidney failure and potential need for kidney transplant following pediatric heart transplantation (KT/pHT). This retrospective, United Network of Organ Sharing study of 10,030 pediatric heart transplants (pHTs) from 1987 to 2020 aimed to determine the incidence of waitlisting for and completion of KT/pHT, risk factors for KT/pHT, and risk factors for nonreceipt of a KT/pHT. Among pHT recipients, 3.4% were waitlisted for KT/pHT (median time of 14 years after pHT). Among those waitlisted, 70% received a KT/pHT, and 18% died on the waitlist at a median time of 0.8 years from KT/pHT waitlisting (median age of 20 years). Moderate-high sensitization at KT/pHT waitlisting (calculated panel reactive antibody, ≥ 20%) was associated with a lower likelihood of KT/pHT (adjusted hazard ratio, 0.67; 95% confidence interval, 0.47-0.95). Waitlisting for heart transplantation simultaneously with kidney transplant (adjusted hazard ratio, 3.73; 95% confidence interval, 2.01-6.92) was associated with increased risk of death on the KT/pHT waitlist. While the prevalence of KT/pHT is low, there is substantial mortality among those waitlisted for KT/pHT. These findings suggest a need to consider novel risk factors for nonreceipt of KT/pHT and death on the waitlist in prioritizing criteria/guidelines for simultaneous heart-kidney transplantation.


Assuntos
Insuficiência Cardíaca , Transplante de Coração , Transplante de Rim , Listas de Espera , Humanos , Transplante de Coração/efeitos adversos , Transplante de Coração/mortalidade , Masculino , Transplante de Rim/efeitos adversos , Feminino , Fatores de Risco , Estudos Retrospectivos , Criança , Prevalência , Adolescente , Pré-Escolar , Adulto Jovem , Seguimentos , Insuficiência Cardíaca/cirurgia , Insuficiência Cardíaca/epidemiologia , Prognóstico , Adulto , Sobrevivência de Enxerto , Lactente , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Obtenção de Tecidos e Órgãos , Taxa de Filtração Glomerular
13.
Biochem Soc Trans ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248209

RESUMO

Histones are essential for maintaining chromatin structure and function. Histone mutations lead to changes in chromatin compaction, gene expression, and the recruitment of DNA repair proteins to the DNA lesion. These disruptions can impair critical DNA repair pathways, such as homologous recombination and non-homologous end joining, resulting in increased genomic instability, which promotes an environment favorable to tumor development and progression. Understanding these mechanisms underscores the potential of targeting DNA repair pathways in cancers harboring mutated histones, offering novel therapeutic strategies to exploit their inherent genomic instability for better treatment outcomes. Here, we examine how mutations in histone H3 disrupt normal chromatin function and DNA damage repair processes and how these mechanisms can be exploited for therapeutic interventions.

14.
Phys Rev Lett ; 132(15): 150604, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682960

RESUMO

We report the first hybrid matter-photon implementation of verifiable blind quantum computing. We use a trapped-ion quantum server and a client-side photonic detection system networked via a fiber-optic quantum link. The availability of memory qubits and deterministic entangling gates enables interactive protocols without postselection-key requirements for any scalable blind server, which previous realizations could not provide. We quantify the privacy at ≲0.03 leaked classical bits per qubit. This experiment demonstrates a path to fully verified quantum computing in the cloud.

15.
Pediatr Transplant ; 28(4): e14765, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38778713

RESUMO

BACKGROUND: Tuberous sclerosis complex (TSC) is a disorder of the mammalian target of the rapamycin (mTOR) pathway associated with the development of multisystem tumors, including renal angiomyolipoma (AML). These renal tumors are benign by nature but locally invasive and carry a risk for the progression of chronic kidney disease (CKD) to end stage kidney disease (ESKD). The frequency of subsequent renal transplantation in this population is largely uncharacterized, although single-center data suggests that 5%-15% of adult TSC patients are kidney transplant recipients. METHODS: This retrospective cohort study utilized United Network for Organ Sharing (UNOS) data. We included candidates waitlisted between 1987 and 2020 for a first kidney transplant with TSC-associated kidney failure. We utilized descriptive statistics to characterize the frequency of first-time kidney transplant waitlisting and transplantation among persons with TSC and the Fine-Gray subdistribution hazard model to evaluate characteristics associated with progression from waitlist. RESULTS: We identified 200 TSC-associated kidney failure patients within the waitlist cohort. Of these, 12 were pediatric patients. Two-thirds (N = 134) of waitlisted persons were female. One hundred forty patients received a transplant with a median waitlist time of 2 years. Younger age at waitlisting was associated with a greater probability of progressing to transplant (HR 0.98 [95% CI: 0.96-0.99]). 91.8% of kidney transplant recipients survived 1-year post-transplant with a functioning allograft. CONCLUSIONS: The majority of patients with TSC who are waitlisted for a kidney transplant progress onto transplantation with excellent 1-year post transplant patient and allograft survival.


Assuntos
Transplante de Rim , Esclerose Tuberosa , Listas de Espera , Humanos , Esclerose Tuberosa/complicações , Esclerose Tuberosa/cirurgia , Feminino , Masculino , Estudos Retrospectivos , Adolescente , Criança , Adulto , Adulto Jovem , Pré-Escolar , Falência Renal Crônica/cirurgia , Lactente , Progressão da Doença
16.
Nature ; 555(7694): 75-78, 2018 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-29493595

RESUMO

Quantum bits (qubits) based on individual trapped atomic ions are a promising technology for building a quantum computer. The elementary operations necessary to do so have been achieved with the required precision for some error-correction schemes. However, the essential two-qubit logic gate that is used to generate quantum entanglement has hitherto always been performed in an adiabatic regime (in which the gate is slow compared with the characteristic motional frequencies of the ions in the trap), resulting in logic speeds of the order of 10 kilohertz. There have been numerous proposals of methods for performing gates faster than this natural 'speed limit' of the trap. Here we implement one such method, which uses amplitude-shaped laser pulses to drive the motion of the ions along trajectories designed so that the gate operation is insensitive to the optical phase of the pulses. This enables fast (megahertz-rate) quantum logic that is robust to fluctuations in the optical phase, which would otherwise be an important source of experimental error. We demonstrate entanglement generation for gate times as short as 480 nanoseconds-less than a single oscillation period of an ion in the trap and eight orders of magnitude shorter than the memory coherence time measured in similar calcium-43 hyperfine qubits. The power of the method is most evident at intermediate timescales, at which it yields a gate error more than ten times lower than can be attained using conventional techniques; for example, we achieve a 1.6-microsecond-duration gate with a fidelity of 99.8 per cent. Faster and higher-fidelity gates are possible at the cost of greater laser intensity. The method requires only a single amplitude-shaped pulse and one pair of beams derived from a continuous-wave laser. It offers the prospect of combining the unrivalled coherence properties, operation fidelities and optical connectivity of trapped-ion qubits with the submicrosecond logic speeds that are usually associated with solid-state devices.

17.
Gen Comp Endocrinol ; 357: 114595, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39059616

RESUMO

Immunosenescence corresponds to the progressive decline of immune functions with increasing age. Although it is critical to understand what modulates such a decline, the ecological and physiological drivers of immunosenescence remain poorly understood in the wild. Among them, the level of glucocorticoids (GCs) during early life are good candidates to modulate immunosenescence patterns because these hormones can have long-term consequences on individual physiology. Indeed, GCs act as regulators of energy allocation to ensure allostasis, are part of the stress response triggered by unpredictable events and have immunosuppressive effects when chronically elevated. We used longitudinal data collected over two decades in two populations of roe deer (Capreolus capreolus) to test whether higher baseline GC levels measured within the first year of life were associated with a more pronounced immunosenescence and parasite susceptibility. We first assessed immunosenescence trajectories in these populations facing contrasting environmental conditions. Then, we found that juvenile GC levels can modulate lymphocyte trajectory. Lymphocyte depletion was accelerated late in life when GCs were elevated early in life. Although the exact mechanism remains to be elucidated, it could involve a role of GCs on thymic characteristics. In addition, elevated GC levels in juveniles were associated with a higher abundance of lung parasites during adulthood for individuals born during bad years, suggesting short-term negative effects of GCs on juvenile immunity, having in turn long-lasting consequences on adult parasite load, depending on juvenile environmental conditions. These findings offer promising research directions in assessing the carry-over consequences of GCs on life-history traits in the wild.


Assuntos
Cervos , Glucocorticoides , Animais , Cervos/fisiologia , Contagem de Linfócitos , Imunossenescência , Feminino , Envelhecimento , Masculino , Linfócitos/metabolismo , Linfócitos/imunologia
18.
Anaesthesia ; 79(5): 514-523, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38214067

RESUMO

The 7th National Audit Project (NAP7) of the Royal College of Anaesthetists studied peri-operative cardiac arrest. Additional inclusion criteria for obstetric anaesthesia were: cardiac arrest associated with neuraxial block performed by an anaesthetist outside the operating theatre (labour epidural analgesia); and cardiac arrest associated with remifentanil patient-controlled analgesia. There were 28 cases of cardiac arrest in obstetric patients, representing 3% of all cardiac arrests reported to NAP7, giving an incidence of 7.9 per 100,000 (95%CI 5.4-11.4 per 100,000). Obstetric patients were approximately four times less likely to have a cardiac arrest during anaesthesia care than patients having non-obstetric surgery. The single leading cause of peri-operative cardiac arrest in obstetric patients was haemorrhage, with underestimated severity and inadequate early resuscitation being contributory factors. When taken together, anaesthetic causes, high neuraxial block and bradyarrhythmia associated with spinal anaesthesia were the leading causes overall. Two patients had a cardiac arrest related to labour neuraxial analgesia. There were no cardiac arrests related to failed airway management or remifentanil patient-controlled analgesia.


Assuntos
Anestesia Obstétrica , Anestésicos , Parada Cardíaca , Gravidez , Feminino , Humanos , Remifentanil , Anestesia Obstétrica/efeitos adversos , Anestesistas , Parada Cardíaca/epidemiologia , Parada Cardíaca/etiologia
19.
Anaesthesia ; 79(5): 506-513, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38173364

RESUMO

The 7th National Audit Project of the Royal College of Anaesthetists studied peri-operative cardiac arrest in the UK. We report the results of the vascular surgery cohort from the 12-month case registry, from 16 June 2021 to 15 June 2022. Anaesthesia for vascular surgery accounted for 2% of UK anaesthetic caseload and included 69 (8%) reported peri-operative cardiac arrests, giving an estimated incidence of 1 in 670 vascular anaesthetics (95%CI 1 in 520-830). The high-risk nature of the vascular population is reflected by the proportion of patients who were ASA physical status 4 (30, 43%) or 5 (19, 28%); the age of patients (80% aged > 65 y); and that most cardiac arrests (57, 83%) occurred during non-elective surgery. The most common vascular surgical procedures among patients who had a cardiac arrest were: aortic surgery (38, 55%); lower-limb revascularisation (13, 19%); and lower-limb amputation (8, 12%). Among patients having vascular surgery and who had a cardiac arrest, 28 (41%) presented with a ruptured abdominal aortic aneurysm. There were 48 (70%) patients who had died at the time of reporting to NAP7 and 11 (16%) were still in hospital, signifying poorer outcomes compared with the non-vascular surgical cohort. The most common cause of cardiac arrest was major haemorrhage (39, 57%), but multiple other causes reflected the critical illness of the patients and the complexity of surgery. This is the first analysis of the incidence, management and outcomes of peri-operative cardiac arrest during vascular anaesthesia in the UK.


Assuntos
Anestesia , Anestésicos , Parada Cardíaca , Humanos , Anestesia/efeitos adversos , Procedimentos Cirúrgicos Vasculares , Anestesistas , Parada Cardíaca/epidemiologia , Parada Cardíaca/terapia , Parada Cardíaca/etiologia
20.
Anaesthesia ; 79(1): 18-30, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37972476

RESUMO

The 7th National Audit Project of the Royal College of Anaesthetists studied peri-operative cardiac arrest in the UK, a topic of importance to patients, anaesthetists and surgeons. Here we report the results of the 12-month registry, from 16 June 2021 to 15 June 2022, focusing on epidemiology and clinical features. We reviewed 881 cases of peri-operative cardiac arrest, giving an incidence of 3 in 10,000 anaesthetics (95%CI 3.0-3.5 per 10,000). Incidence varied with patient and surgical factors. Compared with denominator survey activity, patients with cardiac arrest: included more males (56% vs. 42%); were older (median (IQR) age 60.5 (40.5-80.5) vs. 50.5 (30.5-70.5) y), although the age distribution was bimodal, with infants and patients aged > 66 y overrepresented; and were notably more comorbid (73% ASA physical status 3-5 vs. 27% ASA physical status 1-2). The surgical case-mix included more weekend (14% vs. 11%), out-of-hours (19% vs. 10%), non-elective (65% vs. 30%) and major/complex cases (60% vs. 28%). Cardiac arrest was most prevalent in orthopaedic trauma (12%), lower gastrointestinal surgery (10%), cardiac surgery (9%), vascular surgery (8%) and interventional cardiology (6%). Specialities with the highest proportion of cases relative to denominator activity were: cardiac surgery (9% vs. 1%); cardiology (8% vs. 1%); and vascular surgery (8% vs. 2%). The most common causes of cardiac arrest were: major haemorrhage (17%); bradyarrhythmia (9%); and cardiac ischaemia (7%). Patient factors were judged a key cause of cardiac arrest in 82% of cases, anaesthesia in 40% and surgery in 35%.


Assuntos
Parada Cardíaca , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anestesia , Anestésicos , Anestesistas , Parada Cardíaca/epidemiologia , Parada Cardíaca/etiologia , Lactente
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