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1.
Immunity ; 57(7): 1514-1532.e15, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38788712

RESUMO

Receptor-interacting serine/threonine-protein kinase 1 (RIPK1) functions as a critical stress sentinel that coordinates cell survival, inflammation, and immunogenic cell death (ICD). Although the catalytic function of RIPK1 is required to trigger cell death, its non-catalytic scaffold function mediates strong pro-survival signaling. Accordingly, cancer cells can hijack RIPK1 to block necroptosis and evade immune detection. We generated a small-molecule proteolysis-targeting chimera (PROTAC) that selectively degraded human and murine RIPK1. PROTAC-mediated depletion of RIPK1 deregulated TNFR1 and TLR3/4 signaling hubs, accentuating the output of NF-κB, MAPK, and IFN signaling. Additionally, RIPK1 degradation simultaneously promoted RIPK3 activation and necroptosis induction. We further demonstrated that RIPK1 degradation enhanced the immunostimulatory effects of radio- and immunotherapy by sensitizing cancer cells to treatment-induced TNF and interferons. This promoted ICD, antitumor immunity, and durable treatment responses. Consequently, targeting RIPK1 by PROTACs emerges as a promising approach to overcome radio- or immunotherapy resistance and enhance anticancer therapies.


Assuntos
Morte Celular Imunogênica , Proteólise , Proteína Serina-Treonina Quinases de Interação com Receptores , Transdução de Sinais , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Humanos , Animais , Camundongos , Proteólise/efeitos dos fármacos , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Morte Celular Imunogênica/efeitos dos fármacos , Necroptose/efeitos dos fármacos , Necroptose/imunologia , Neoplasias/imunologia , Neoplasias/tratamento farmacológico , Camundongos Endogâmicos C57BL , Antineoplásicos/farmacologia , Imunoterapia/métodos
2.
Proc Natl Acad Sci U S A ; 121(7): e2316569121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38330016

RESUMO

Clay minerals are implicated in the retention of biomolecules within organic matter in many soil environments. Spectroscopic studies have proposed several mechanisms for biomolecule adsorption on clays. Here, we employ molecular dynamics simulations to investigate these mechanisms in hydrated adsorbate conformations of montmorillonite, a smectite-type clay, with ten biomolecules of varying chemistry and structure, including sugars related to cellulose and hemicellulose, lignin-related phenolic acid, and amino acids with different functional groups. Our molecular modeling captures biomolecule-clay and biomolecule-biomolecule interactions that dictate selectivity and competition in adsorption retention and interlayer nanopore trapping, which we determine experimentally by NMR and X-ray diffraction, respectively. Specific adsorbate structures are important in facilitating the electrostatic attraction and Van der Waals energies underlying the hierarchy in biomolecule adsorption. Stabilized by a network of direct and water-bridged hydrogen bonds, favorable electrostatic interactions drive this hierarchy whereby amino acids with positively charged side chains are preferentially adsorbed on the negatively charged clay surface compared to the sugars and carboxylate-rich aromatics and amino acids. With divalent metal cations, our model adsorbate conformations illustrate hydrated metal cation bridging of carboxylate-containing biomolecules to the clay surface, thus explaining divalent cation-promoted adsorption from our experimental data. Adsorption experiments with a mixture of biomolecules reveal selective inhibition in biomolecule adsorption, which our molecular modeling attributes to electrostatic biomolecule-biomolecule pairing that is more energetically favorable than the biomolecule-clay complex. In sum, our findings highlight chemical and structural features that can inform hypotheses for predicting biomolecule adsorption at water-clay interfaces.


Assuntos
Simulação de Dinâmica Molecular , Água , Argila , Adsorção , Água/química , Eletricidade Estática , Aminoácidos , Açúcares
3.
Mol Cell ; 66(5): 698-710.e5, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28506461

RESUMO

TNF is an inflammatory cytokine that upon binding to its receptor, TNFR1, can drive cytokine production, cell survival, or cell death. TNFR1 stimulation causes activation of NF-κB, p38α, and its downstream effector kinase MK2, thereby promoting transcription, mRNA stabilization, and translation of target genes. Here we show that TNF-induced activation of MK2 results in global RIPK1 phosphorylation. MK2 directly phosphorylates RIPK1 at residue S321, which inhibits its ability to bind FADD/caspase-8 and induce RIPK1-kinase-dependent apoptosis and necroptosis. Consistently, a phospho-mimetic S321D RIPK1 mutation limits TNF-induced death. Mechanistically, we find that phosphorylation of S321 inhibits RIPK1 kinase activation. We further show that cytosolic RIPK1 contributes to complex-II-mediated cell death, independent of its recruitment to complex-I, suggesting that complex-II originates from both RIPK1 in complex-I and cytosolic RIPK1. Thus, MK2-mediated phosphorylation of RIPK1 serves as a checkpoint within the TNF signaling pathway that integrates cell survival and cytokine production.


Assuntos
Apoptose/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Animais , Caspase 8/metabolismo , Relação Dose-Resposta a Droga , Proteína de Domínio de Morte Associada a Fas/metabolismo , Células HT29 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , MAP Quinase Quinase Quinases/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Complexos Multiproteicos , NF-kappa B/metabolismo , Necrose , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Interferência de RNA , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Transdução de Sinais/efeitos dos fármacos , Transfecção
4.
Lancet ; 401(10393): 2051-2059, 2023 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-37209706

RESUMO

BACKGROUND: Tonsillectomy is regularly performed in adults with acute tonsillitis, but with scarce evidence. A reduction in tonsillectomies has coincided with an increase in acute adult hospitalisation for tonsillitis complications. We aimed to assess the clinical effectiveness and cost-effectiveness of conservative management versus tonsillectomy in patients with recurrent acute tonsillitis. METHODS: This pragmatic multicentre, open-label, randomised controlled trial was conducted in 27 hospitals in the UK. Participants were adults aged 16 years or older who were newly referred to secondary care otolaryngology clinics with recurrent acute tonsillitis. Patients were randomly assigned (1:1) to receive tonsillectomy or conservative management using random permuted blocks of variable length. Stratification by recruiting centre and baseline symptom severity was assessed using the Tonsil Outcome Inventory-14 score (categories defined as mild 0-35, moderate 36-48, or severe 49-70). Participants in the tonsillectomy group received elective surgery to dissect the palatine tonsils within 8 weeks after random assignment and those in the conservative management group received standard non-surgical care during 24 months. The primary outcome was the number of sore throat days collected during 24 months after random assignment, reported once per week with a text message. The primary analysis was done in the intention-to-treat (ITT) population. This study is registered with the ISRCTN registry, 55284102. FINDINGS: Between May 11, 2015, and April 30, 2018, 4165 participants with recurrent acute tonsillitis were assessed for eligibility and 3712 were excluded. 453 eligible participants were randomly assigned (233 in the immediate tonsillectomy group vs 220 in the conservative management group). 429 (95%) patients were included in the primary ITT analysis (224 vs 205). The median age of participants was 23 years (IQR 19-30), with 355 (78%) females and 97 (21%) males. Most participants were White (407 [90%]). Participants in the immediate tonsillectomy group had fewer days of sore throat during 24 months than those in the conservative management group (median 23 days [IQR 11-46] vs 30 days [14-65]). After adjustment for site and baseline severity, the incident rate ratio of total sore throat days in the immediate tonsillectomy group (n=224) compared with the conservative management group (n=205) was 0·53 (95% CI 0·43 to 0·65; <0·0001). 191 adverse events in 90 (39%) of 231 participants were deemed related to tonsillectomy. The most common adverse event was bleeding (54 events in 44 [19%] participants). No deaths occurred during the study. INTERPRETATION: Compared with conservative management, immediate tonsillectomy is clinically effective and cost-effective in adults with recurrent acute tonsillitis. FUNDING: National Institute for Health Research.


Assuntos
Faringite , Transtornos Respiratórios , Tonsilectomia , Tonsilite , Masculino , Feminino , Humanos , Adulto , Adulto Jovem , Tonsilectomia/efeitos adversos , Tratamento Conservador , Tonsilite/cirurgia , Tonsilite/complicações , Faringite/etiologia , Dor/etiologia , Reino Unido/epidemiologia
5.
Acta Anaesthesiol Scand ; 68(2): 146-166, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37881881

RESUMO

BACKGROUND: The optimal dose of dexamethasone for severe/critical COVID-19 is uncertain. We compared higher versus standard doses of dexamethasone in adults with COVID-19 and hypoxia. METHODS: We searched PubMed and trial registers until 23 June 2023 for randomised clinical trials comparing higher (>6 mg) versus standard doses (6 mg) of dexamethasone in adults with COVID-19 and hypoxia. The primary outcome was mortality at 1 month. Secondary outcomes were mortality closest to 90 days; days alive without life support; and the occurrence of serious adverse events/reactions (SAEs/SARs) closest to 1 month. We assessed the risk of bias using the Cochrane RoB2 tool, risk of random errors using trial sequential analysis, and certainty of evidence using Grading of Recommendations Assessment, Development and Evaluation (GRADE). RESULTS: We included eight trials (2478 participants), of which four (1293 participants) had low risk of bias. Higher doses of dexamethasone probably resulted in little to no difference in mortality at 1 month (relative risk [RR] 0.97, 95% CI: 0.79-1.19), mortality closest to Day 90 (RR 1.01, 95% CI: 0.86-1.20), and SAEs/SARs (RR 1.00, 95% CI: 0.97-1.02). Higher doses of dexamethasone probably increased the number of days alive without invasive mechanical ventilation and circulatory support but had no effect on days alive without renal replacement therapy. CONCLUSIONS: Based on low to moderate certainty evidence, higher versus standard doses of dexamethasone probably result in little to no difference in mortality, SAEs/SARs, and days alive without renal replacement therapy, but probably increase the number of days alive without invasive mechanical ventilation and circulatory support.


Assuntos
COVID-19 , Adulto , Humanos , Tratamento Farmacológico da COVID-19 , Pacientes , Dexametasona/efeitos adversos , Hipóxia
6.
Am J Emerg Med ; 81: 23-34, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38631148

RESUMO

OBJECTIVES: The aim of this review was to identify factors associated with multiple visits to emergency department (ED) services for mental health care in adolescents. METHODS: Electronic databases (MEDLINE, PsycINFO, Embase, CINAHL, Web of Science and ProQuest Dissertations & Thesis Global) were searched for evidence that presented an association between risk factors or correlates of multiple visits to the emergency departmental for mental health care by 10-24 year olds. High impact use was defined as at least one return ED visit for mental health care. Primary studies of any quantitative design were included, with no exclusions based on language or country and all possible risk factors were considered. Data were extracted and synthesised using quantitative methods; frequencies of positive, negative and null associations were summarised for categories of potential risk factors. RESULTS: Sixty-five studies were included in the review. Most studies were from North America and reported a wide range of measures of high impact ED use, the most common being a binary indicator of multiple ED visits. Sex/gender and age were the most frequently reported risk factors. Measure of previous or concurrent access to mental health care was consistently positively associated with high impact use. Having private health insurance, compared with public or no insurance, was generally negatively associated with high impact use. Proxy measures of socioeconomic position (SEP) showed associations between lower SEP and more high impact use in a small number of studies. No other factors were consistently or uniformly associated with high impact use. CONCLUSIONS: The review identified a substantial evidence base but due to the variability in study design and measurement of both risk factors and outcomes, no consistent risk factors emerged. More research is needed, particularly outside North America, using robust methods and high quality routinely collected data.


Assuntos
Serviço Hospitalar de Emergência , Humanos , Adolescente , Serviço Hospitalar de Emergência/estatística & dados numéricos , Fatores de Risco , Serviços de Saúde Mental/estatística & dados numéricos , Transtornos Mentais/terapia , Transtornos Mentais/epidemiologia , Masculino , Criança , Feminino , Adulto Jovem , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Visitas ao Pronto Socorro
7.
Proc Natl Acad Sci U S A ; 118(37)2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34493662

RESUMO

Mitochondria form a complex, interconnected reticulum that is maintained through coordination among biogenesis, dynamic fission, and fusion and mitophagy, which are initiated in response to various cues to maintain energetic homeostasis. These cellular events, which make up mitochondrial quality control, act with remarkable spatial precision, but what governs such spatial specificity is poorly understood. Herein, we demonstrate that specific isoforms of the cellular bioenergetic sensor, 5' AMP-activated protein kinase (AMPKα1/α2/ß2/γ1), are localized on the outer mitochondrial membrane, referred to as mitoAMPK, in various tissues in mice and humans. Activation of mitoAMPK varies across the reticulum in response to energetic stress, and inhibition of mitoAMPK activity attenuates exercise-induced mitophagy in skeletal muscle in vivo. Discovery of a mitochondrial pool of AMPK and its local importance for mitochondrial quality control underscores the complexity of sensing cellular energetics in vivo that has implications for targeting mitochondrial energetics for disease treatment.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Metabolismo Energético , Mitocôndrias/patologia , Mitofagia , Condicionamento Físico Animal , Proteínas Quinases Ativadas por AMP/genética , Animais , Humanos , Masculino , Camundongos , Mitocôndrias/metabolismo
8.
PLoS Med ; 20(1): e1004036, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36701266

RESUMO

BACKGROUND: Preterm birth is the leading cause of perinatal morbidity and mortality and is associated with adverse developmental and long-term health outcomes, including several cardiometabolic risk factors and outcomes. However, evidence about the association of preterm birth with later body size derives mainly from studies using birth weight as a proxy of prematurity rather than an actual length of gestation. We investigated the association of gestational age (GA) at birth with body size from infancy through adolescence. METHODS AND FINDINGS: We conducted a two-stage individual participant data (IPD) meta-analysis using data from 253,810 mother-child dyads from 16 general population-based cohort studies in Europe (Denmark, Finland, France, Italy, Norway, Portugal, Spain, the Netherlands, United Kingdom), North America (Canada), and Australasia (Australia) to estimate the association of GA with body mass index (BMI) and overweight (including obesity) adjusted for the following maternal characteristics as potential confounders: education, height, prepregnancy BMI, ethnic background, parity, smoking during pregnancy, age at child's birth, gestational diabetes and hypertension, and preeclampsia. Pregnancy and birth cohort studies from the LifeCycle and the EUCAN-Connect projects were invited and were eligible for inclusion if they had information on GA and minimum one measurement of BMI between infancy and adolescence. Using a federated analytical tool (DataSHIELD), we fitted linear and logistic regression models in each cohort separately with a complete-case approach and combined the regression estimates and standard errors through random-effects study-level meta-analysis providing an overall effect estimate at early infancy (>0.0 to 0.5 years), late infancy (>0.5 to 2.0 years), early childhood (>2.0 to 5.0 years), mid-childhood (>5.0 to 9.0 years), late childhood (>9.0 to 14.0 years), and adolescence (>14.0 to 19.0 years). GA was positively associated with BMI in the first decade of life, with the greatest increase in mean BMI z-score during early infancy (0.02, 95% confidence interval (CI): 0.00; 0.05, p < 0.05) per week of increase in GA, while in adolescence, preterm individuals reached similar levels of BMI (0.00, 95% CI: -0.01; 0.01, p 0.9) as term counterparts. The association between GA and overweight revealed a similar pattern of association with an increase in odds ratio (OR) of overweight from late infancy through mid-childhood (OR 1.01 to 1.02) per week increase in GA. By adolescence, however, GA was slightly negatively associated with the risk of overweight (OR 0.98 [95% CI: 0.97; 1.00], p 0.1) per week of increase in GA. Although based on only four cohorts (n = 32,089) that reached the age of adolescence, data suggest that individuals born very preterm may be at increased odds of overweight (OR 1.46 [95% CI: 1.03; 2.08], p < 0.05) compared with term counterparts. Findings were consistent across cohorts and sensitivity analyses despite considerable heterogeneity in cohort characteristics. However, residual confounding may be a limitation in this study, while findings may be less generalisable to settings in low- and middle-income countries. CONCLUSIONS: This study based on data from infancy through adolescence from 16 cohort studies found that GA may be important for body size in infancy, but the strength of association attenuates consistently with age. By adolescence, preterm individuals have on average a similar mean BMI to peers born at term.


Assuntos
Sobrepeso , Nascimento Prematuro , Criança , Gravidez , Feminino , Humanos , Recém-Nascido , Lactente , Pré-Escolar , Adolescente , Sobrepeso/epidemiologia , Sobrepeso/complicações , Idade Gestacional , Fatores de Risco , Nascimento Prematuro/epidemiologia , Estudos de Coortes , Peso ao Nascer , Índice de Massa Corporal
10.
Acc Chem Res ; 55(20): 3057-3069, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36170613

RESUMO

Cyclopropenium ions are the smallest class of aromatic compounds, satisfying Hückel's rules of aromaticity with two π electrons within a three-membered ring. First prepared by Breslow in 1957, cyclopropenium ions have been found to possess extraordinary stability despite being both cationic and highly strained. In the 65 years since their first preparation, cyclopropenium ions have been the subject of innumerable studies concerning their synthesis, physical properties, and reactivity. However, prior to our work, the reactivity of these unique carbocations had not been exploited for reaction promotion or catalysis.Over the past 13 years, we have been exploring aromatic ions as unique and versatile building blocks for the development of catalysts for organic chemistry. A major portion of this work has been focused on leveraging the remarkable properties of the smallest of the aromatic ions─cyclopropeniums─as a design element in the invention of highly reactive catalysts. Indeed, because of its unique profile of hydrolytic stability, compact geometry, and relatively easy oxidizability, the cyclopropenium ring has proven to be a highly advantageous construction module for catalyst invention.In this Account, we describe some of our work using cyclopropenium ions as a key element in the design of novel catalysts. First, we discuss our early work aimed at promoting dehydrative reactions, starting with Appel-type chlorodehydrations of alcohols and carboxylic acids, cyclic ether formations, and Beckmann rearrangements and culminating in the realization of catalytic chlorodehydrations of alcohols and a catalytic Mitsunobu-type reaction. Next, we describe the development of cyclopropenimines as strong, neutral organic Brønsted bases and, in particular, the use of chiral cyclopropenimines for enantioselective Brønsted catalysis. We also describe the development of higher-order cyclopropenimine superbases. The use of tris(amino)cyclopropenium (TAC) ions as a novel class of phase-transfer catalysts is discussed for the reaction of epoxides with carbon dioxide. Next, we describe the formation of a cyclopropenone radical cation that has a portion of its spin density on the oxygen atom, leading to some peculiar metal ligand behavior. Finally, we discuss recent work that employs TAC electrophotocatalysts for oxidation reactions. The key intermediate for this chemistry is a TAC radical dication, which as an open-shell photocatalyst has remarkably strong excited-state oxidizing power. We describe the application of this strategy to transformations ranging from the oxidative functionalization of unactivated arenes to the regioselective derivatization of ethers, C-H aminations, vicinal C-H diaminations, and finally aryl olefin dioxygenations. Collectively, these catalytic platforms demonstrate the utility of charged aromatic rings, and cyclopropenium ions in particular, to enable unique advances in catalysis.


Assuntos
Alcenos , Dióxido de Carbono , Ácidos Carboxílicos , Catálise , Compostos de Epóxi , Éteres , Íons , Ligantes , Oxigênio
11.
MMWR Morb Mortal Wkly Rep ; 72(50): 1338-1345, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38096119

RESUMO

In the United States, unintentional injury is the fourth leading cause of death among infants (i.e., children aged <1 year) and is the top cause of death among children and adolescents aged 1-17 years; firearms are a leading injury method. Unsecured firearms (e.g., unlocked and loaded) are associated with risk for unintentional childhood firearm injury death. Data recorded during 2003-2021 by the National Violent Death Reporting System (NVDRS) from 49 states, the District of Columbia, and Puerto Rico were used to characterize unintentional firearm injury deaths of U.S. infants, children, and adolescents aged 0-17 years (referred to as children in this report). NVDRS identified 1,262 unintentional firearm injury deaths among children aged 0-17 years: the largest percentage (33%) of these deaths were among children aged 11-15 years, followed by 29% among those aged 0-5 years, 24% among those aged 16-17 years, and 14% among persons aged 6-10 years. Overall, 83% of unintentional firearm injury deaths occurred among boys. The majority (85%) of victims were fatally injured at a house or apartment, including 56% in their own home. Approximately one half (53%) of fatal unintentional firearm injuries to children were inflicted by others; 38% were self-inflicted. In 9% of incidents, it was unknown whether the injury was self- or other-inflicted. Approximately two thirds (67%) of shooters were playing with or showing the firearm to others when it discharged. Overall, firearms used in unintentional injury deaths were often stored loaded (74%) and unlocked (76%) and were most commonly accessed from nightstands and other sleeping areas (30%). Unintentional firearm injury deaths of children are preventable. Secured firearm storage practices (e.g., storing firearms locked, unloaded, and separate from ammunition) have been identified as protective factors against child firearm injuries and deaths, underscoring the importance of policymakers, health care professionals (e.g., pediatricians), and others partnering with parents, caregivers, and firearm owners to promote secure firearm storage.


Assuntos
Armas de Fogo , Suicídio , Ferimentos por Arma de Fogo , Criança , Lactente , Masculino , Humanos , Estados Unidos/epidemiologia , Adolescente , Homicídio , Causas de Morte , Violência , Vigilância da População , District of Columbia
12.
BMC Med Res Methodol ; 23(1): 241, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853353

RESUMO

BACKGROUND: Near-real time surveillance of excess mortality has been an essential tool during the COVID-19 pandemic. It remains critical for monitoring mortality as the pandemic wanes, to detect fluctuations in the death rate associated both with the longer-term impact of the pandemic (e.g. infection, containment measures and reduced service provision by the health and other systems) and the responses that followed (e.g. curtailment of containment measures, vaccination and the response of health and other systems to backlogs). Following the relaxing of social distancing regimes and reduction in the availability of testing, across many countries, it becomes critical to measure the impact of COVID-19 infection. However, prolonged periods of mortality in excess of the expected across entire populations has raised doubts over the validity of using unadjusted historic estimates of mortality to calculate the expected numbers of deaths that form the baseline for computing numbers of excess deaths because many individuals died earlier than they would otherwise have done: i.e. their mortality was displaced earlier in time to occur during the pandemic rather than when historic rates predicted. This is also often termed "harvesting" in the literature. METHODS: We present a novel Cox-regression-based methodology using time-dependent covariates to estimate the profile of the increased risk of death across time in individuals who contracted COVID-19 among a population of hip fracture patients in England (N = 98,365). We use these hazards to simulate a distribution of survival times, in the presence of a COVID-19 positive test, and then calculate survival times based on hazard rates without a positive test and use the difference between the medians of these distributions to estimate the number of days a death has been displaced. This methodology is applied at the individual level, rather than the population level to provide a better understanding of the impact of a positive COVID-19 test on the mortality of groups with different vulnerabilities conferred by sociodemographic and health characteristics. Finally, we apply the mortality displacement estimates to adjust estimates of excess mortality using a "ball and urn" model. RESULTS: Among the exemplar population we present an end-to-end application of our methodology to estimate the extent of mortality displacement. A greater proportion of older, male and frailer individuals were subject to significant displacement while the magnitude of displacement was higher in younger females and in individuals with lower frailty: groups who, in the absence of COVID-19, should have had a substantial life expectancy. CONCLUSION: Our results indicate that calculating the expected number of deaths following the first wave of the pandemic in England based solely on historical trends results in an overestimate, and excess mortality will therefore be underestimated. Our findings, using this exemplar dataset are conditional on having experienced a hip fracture, which is not generalisable to the general population. Fractures that impede mobility in the weeks that follow the accident/surgery considerably shorten life expectancy and are in themselves markers of significant frailty. It is therefore important to apply these novel methods to the general population, among whom we anticipate strong patterns in mortality displacement - both in its length and prevalence - by age, sex, frailty and types of comorbidities. This counterfactual method may also be used to investigate a wider range of disruptive population health events. This has important implications for public health monitoring and the interpretation of public health data in England and globally.


Assuntos
COVID-19 , Fragilidade , Fraturas do Quadril , Feminino , Humanos , Masculino , COVID-19/epidemiologia , Pandemias , Expectativa de Vida , Fraturas do Quadril/epidemiologia , Mortalidade
13.
Eur Child Adolesc Psychiatry ; 32(11): 2323-2334, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36107256

RESUMO

The objective of the present study is to investigate the impact of Sex Chromosome Trisomy (SCT; XXX, XXY, XYY) on the early appearance of Autism Spectrum Disorder (ASD) symptoms, and the predictive value of Joint Attention for symptoms of ASD. SCTs are specific genetic conditions that may serve as naturalistic 'at risk' models of neurodevelopment, as they are associated with increased risk for neurobehavioral vulnerabilities. A group of 82 children with SCT (aged 1-8 years) was included at baseline of this longitudinal study. Joint Attention was measured at baseline with structured behavior observations according to the Early Social Communication Scales. ASD symptoms were assessed with the Modified Checklist for Autism in Toddlers questionnaire and Autism Diagnostic Interview-Revised in a 1-year follow-up. Recruitment and assessment took place in the Netherlands and in the United States. The results demonstrate that ASD symptoms were substantially higher in children with SCT compared to the general population, with 22% of our cohort at clinical risk for ASD, especially in the domain of social interaction and communication. Second, a predictive value of Joint Attention was found for ASD symptoms at 1-year follow-up. In this cohort, no differences were found between karyotype-subtypes. In conclusion, from a very early age, SCT can be associated with an increased risk for vulnerabilities in adaptive social functioning. These findings show a neurodevelopmental impact of the extra X or Y chromosome on social adaptive development associated with risk for ASD already from early childhood onward. These findings advocate for close monitoring and early (preventive) support, aimed to optimize social development of young children with SCT.


Assuntos
Transtorno do Espectro Autista , Humanos , Pré-Escolar , Lactente , Criança , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/complicações , Trissomia/diagnóstico , Trissomia/genética , Estudos Longitudinais , Cromossomos Sexuais , Atenção
14.
Mol Reprod Dev ; 89(11): 540-553, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36094907

RESUMO

Fetal growth restriction (FGR) significantly contributes to neonatal and perinatal morbidity and mortality. Currently, there are no effective treatment options for FGR during pregnancy. We have developed a nanoparticle gene therapy targeting the placenta to increase expression of human insulin-like growth factor 1 (hIGF1) to correct fetal growth trajectories. Using the maternal nutrient restriction guinea pig model of FGR, an ultrasound-guided, intraplacental injection of nonviral, polymer-based hIGF1 nanoparticle containing plasmid with the hIGF1 gene and placenta-specific Cyp19a1 promotor was administered at mid-pregnancy. Sustained hIGF1 expression was confirmed in the placenta 5 days after treatment. Whilst increased hIGF1 did not change fetal weight, circulating fetal glucose concentration were 33%-67% higher. This was associated with increased expression of glucose and amino acid transporters in the placenta. Additionally, hIGF1 nanoparticle treatment increased the fetal capillary volume density in the placenta, and reduced interhaemal distance between maternal and fetal circulation. Overall, our findings, that trophoblast-specific increased expression of hIGF1 results in changes to glucose transporter expression and increases fetal glucose concentrations within a short time period, highlights the translational potential this treatment could have in correcting impaired placental nutrient transport in human pregnancies complicated by FGR.


Assuntos
Fator de Crescimento Insulin-Like I , Nanopartículas , Animais , Cobaias , Gravidez , Feminino , Humanos , Fator de Crescimento Insulin-Like I/genética , Placenta/metabolismo , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/metabolismo , Transgenes , Nutrientes , Glucose
15.
Am J Physiol Regul Integr Comp Physiol ; 320(5): R653-R662, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33621475

RESUMO

Currently, there is no effective treatment for placental dysfunction in utero. In a ligated mouse model of fetal growth restriction (FGR), nanoparticle-mediated human insulin-like 1 growth factor (hIGF1) gene delivery (NP-Plac1-hIGF1) increased hIGF1 expression and maintained fetal growth. However, whether it can restore fetal growth remains to be determined. Using the endothelial nitric oxide synthase knockout (eNOS-/-) mouse model, a genetic model of FGR, we found that despite inducing expression of hIGF1 in the placentas treated with NP-Plac1-hIGF1 (P = 0.0425), FGR did not resolve. This was associated with no change to the number of fetal capillaries in the placental labyrinth; an outcome which was increased with NP-Plac1-hIGF1 treatment in the ligated mouse model, despite increased expression of angiopoietin 1 (P = 0.05), and suggested IGF1 signaling in the placenta requires eNOS to modulate placenta angiogenesis. To further assess this hypothesis, BeWo choriocarcinoma cell line and human placental explant cultures were treated with NP-Plac1-hIGF1, oxidative stress was induced with hydrogen peroxide (H2O2), and NOS activity was inhibited using the inhibitor NG-monomethyl-l-arginine (l-NMMA). In both BeWo cells and explants, the protective effect of NP-Plac1-hIGF1 treatment against H2O2-induced cell death/lactate dehydrogenase release was prevented by eNOS inhibition (P = 0.003 and P < 0.0001, respectively). This was associated with an increase in mRNA expression of oxidative stress markers hypoxia inducing factor 1α (HIF1α; P < 0.0001) and ADAM10 (P = 0.0002) in the NP-Plac1-hIGF1 + H2O2 + l-NMMA-treated BeWo cells. These findings show for the first time the requirement of eNOS/NOS in IGF1 signaling in placenta cells that may have implications for placental angiogenesis and fetal growth.


Assuntos
Retardo do Crescimento Fetal/terapia , Feto/irrigação sanguínea , Terapia Genética , Fator de Crescimento Insulin-Like I/metabolismo , Neovascularização Fisiológica , Óxido Nítrico Sintase Tipo III/metabolismo , Placenta/irrigação sanguínea , Trofoblastos/enzimologia , Proteína ADAM10/genética , Proteína ADAM10/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Desenvolvimento Fetal , Retardo do Crescimento Fetal/enzimologia , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/fisiopatologia , Técnicas de Transferência de Genes , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fator de Crescimento Insulin-Like I/genética , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nanopartículas , Óxido Nítrico Sintase Tipo III/genética , Estresse Oxidativo , Gravidez , Transdução de Sinais , Técnicas de Cultura de Tecidos , Trofoblastos/patologia
16.
Reproduction ; 161(2): 135-144, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33434162

RESUMO

Animal models are needed to develop interventions to prevent or treat intrauterine growth restriction (IUGR). Foetal growth rates and effects of in utero exposures differ between sexes, but little is known about sex-specific effects of increasing litter size. We established a murine IUGR model using pregnancies generated by multiple embryo transfers, and evaluated sex-specific responses to increasing litter size. CBAF1 embryos were collected at gestation day 0.5 (GD0.5) and 6, 8, 10 or 12 embryos were transferred into each uterine horn of pseudopregnant female CD1 mice (n = 32). Foetal and placental outcomes were measured at GD18.5. In the main experiment, foetuses were genotyped (Sry) for analysis of sex-specific outcomes. The number of implantation sites (P = 0.033) and litter size (number of foetuses, P = 0.008) correlated positively with the number of embryos transferred, while placental weight correlated negatively with litter size (both P < 0.01). The relationship between viable litter size and foetal weight differed between sexes (interaction P = 0.002), such that foetal weights of males (P = 0.002), but not females (P = 0.233), correlated negatively with litter size. Placental weight decreased with increasing litter size (P < 0.001) and was lower in females than males (P = 0.020). Our results suggest that male foetuses grow as fast as permitted by nutrient supply, whereas the female maintains placental reserve capacity. This strategy reflecting sex-specific gene expression is likely to place the male foetus at greater risk of death in the event of a 'second hit'.


Assuntos
Retardo do Crescimento Fetal , Placenta , Animais , Modelos Animais de Doenças , Transferência Embrionária , Feminino , Peso Fetal , Tamanho da Ninhada de Vivíparos , Masculino , Camundongos , Gravidez
17.
FASEB J ; 34(6): 7330-7344, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32304342

RESUMO

Our understanding of the molecular mechanisms underlying adaptations to resistance exercise remains elusive despite the significant biological and clinical relevance. We developed a novel voluntary mouse weightlifting model, which elicits squat-like activities against adjustable load during feeding, to investigate the resistance exercise-induced contractile and metabolic adaptations. RNAseq analysis revealed that a single bout of weightlifting induced significant transcriptome responses of genes that function in posttranslational modification, metabolism, and muscle differentiation in recruited skeletal muscles, which were confirmed by increased expression of fibroblast growth factor-inducible 14 (Fn14), Down syndrome critical region 1 (Dscr1) and Nuclear receptor subfamily 4, group A, member 3 (Nr4a3) genes. Long-term (8 weeks) voluntary weightlifting training resulted in significantly increases of muscle mass, protein synthesis (puromycin incorporation in SUnSET assay) and mTOR pathway protein expression (raptor, 4e-bp-1, and p70S6K proteins) along with enhanced muscle power (specific torque and contraction speed), but not endurance capacity, mitochondrial biogenesis, and fiber type transformation. Importantly, weightlifting training profound improved whole-body glucose clearance and skeletal muscle insulin sensitivity along with enhanced autophagy (increased LC3 and LC3-II/I ratio, and decreased p62/Sqstm1). These data suggest that resistance training in mice promotes muscle adaptation and insulin sensitivity with simultaneous enhancement of autophagy and mTOR pathway.


Assuntos
Adaptação Fisiológica/fisiologia , Autofagia/fisiologia , Resistência à Insulina/fisiologia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Condicionamento Físico Animal/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Contração Muscular/fisiologia , Biogênese de Organelas , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo
18.
Pediatr Res ; 89(7): 1673-1680, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33531677

RESUMO

BACKGROUND: Fetal responses to adverse pregnancy environments are sex-specific. In fetal guinea pigs (GPs), we assessed morphology and messenger RNA (mRNA) expression in fetal growth-restricted (FGR) tissues at midpregnancy. METHODS: Female GPs were assigned either an ad libitum diet (C) or 30% restricted diet (R) prior to pregnancy to midpregnancy. At midpregnancy, a subset of R females underwent ultrasound-guided nanoparticle (NP) injection to enhance placental function. Five days later, fetuses were sampled. Fetal brain, heart, and liver were assessed for morphology (hematoxylin and eosin), proliferation (Ki67), and vascularization (CD31), as well as expression of inflammatory markers. RESULTS: R fetuses were 19% lighter with reduced organ weights and evidence of brain sparing compared to controls. No increased necrosis, proliferation, or vascularization was found between C and R nor male or female fetal organs. Sexual dimorphism in mRNA expression of Tgfß and Ctgf was observed in R but not C fetal brains: increased expression in females. NP treatment increased fetal brain mRNA expression of Tgfß and Ctgf in R males, abolishing the significant difference observed in untreated R fetuses. CONCLUSIONS: Sex-specific differences in mRNA expression in the fetal brain with FGR could impart a potential survival bias and may be useful for the development of treatments for obstetric diseases. IMPACT: Male and female fetuses respond differently to adverse pregnancy environments. Under fetal growth restriction conditions, inflammatory marker mRNA expression in the fetal brain was higher in females compared to males. Differences in gene expression between males and females may confer a selective advantage/disadvantage under adverse conditions. Better characterization of sexual dimorphism in fetal development will aid better development of treatments for obstetric diseases.


Assuntos
Encéfalo/metabolismo , Retardo do Crescimento Fetal/terapia , Expressão Gênica , Caracteres Sexuais , Animais , Feminino , Retardo do Crescimento Fetal/genética , Cobaias , Masculino , Gravidez , RNA Mensageiro/genética
19.
Prev Med ; 153: 106826, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34599921

RESUMO

Worldwide, cancer screening faced significant disruption in 2020 due to the COVID-19 pandemic. If this has led to changes in public attitudes towards screening and reduced intention to participate, there is a risk of long-term adverse impact on cancer outcomes. In this study, we examined previous participation and future intentions to take part in cervical and colorectal cancer (CRC) screening following the first national lockdown in the UK. Overall, 7543 adults were recruited to a cross-sectional online survey in August-September 2020. Logistic regression analyses were used to identify correlates of strong screening intentions among 2319 participants eligible for cervical screening and 2502 eligible for home-based CRC screening. Qualitative interviews were conducted with a sub-sample of 30 participants. Verbatim transcripts were analysed thematically. Of those eligible, 74% of survey participants intended to attend cervical screening and 84% intended to complete home-based CRC screening when next invited. Thirty percent and 19% of the cervical and CRC samples respectively said they were less likely to attend a cancer screening appointment now than before the pandemic. Previous non-participation was the strongest predictor of low intentions for cervical (aOR 26.31, 95% CI: 17.61-39.30) and CRC (aOR 67.68, 95% CI: 33.91-135.06) screening. Interview participants expressed concerns about visiting healthcare settings but were keen to participate when screening programmes resumed. Intentions to participate in future screening were high and strongly associated with previous engagement in both programmes. As screening services recover, it will be important to monitor participation and to ensure people feel safe to attend.


Assuntos
COVID-19 , Neoplasias Colorretais , Neoplasias do Colo do Útero , Adulto , Neoplasias Colorretais/diagnóstico , Controle de Doenças Transmissíveis , Estudos Transversais , Detecção Precoce de Câncer , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Intenção , Programas de Rastreamento , Pandemias , SARS-CoV-2 , Neoplasias do Colo do Útero/diagnóstico
20.
Med Teach ; 43(11): 1278-1285, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34126840

RESUMO

BACKGROUND: Single-best answer questions (SBAQs) are common but are susceptible to cueing. Very short answer questions (VSAQs) could be an alternative, and we sought to determine if students' cognitive processes varied across question types and whether students with different performance levels used different methods for answering questions. METHODS: We undertook a 'think aloud' study, interviewing 21 final year medical students at five UK medical schools. Each student described their thought processes and methods used for eight questions of each type. Responses were coded and quantified to determine the relative frequency with which each method was used, denominated on the number of times a method could have been used. RESULTS: Students were more likely to use analytical reasoning methods (specifically identifying key features) when answering VSAQs. The use of test-taking behaviours was more common for SBAQs; students frequently used the answer options to help them reach an answer. Students acknowledged uncertainty more frequently when answering VSAQs. Analytical reasoning was more commonly used by high-performing students compared with low-performing students. CONCLUSIONS: Our results suggest that VSAQs encourage more authentic clinical reasoning strategies. Differences in cognitive approaches used highlight the need for focused approaches to teaching clinical reasoning and dealing with uncertainty.


Assuntos
Avaliação Educacional , Estudantes de Medicina , Cognição , Humanos , Resolução de Problemas , Faculdades de Medicina
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