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1.
Proc Natl Acad Sci U S A ; 119(41): e2206504119, 2022 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-36191202

RESUMEN

The expansive gyres of the subtropical ocean account for a significant fraction of global organic carbon export from the upper ocean. In the gyre interior, vertical mixing and the heaving of nutrient-rich waters into the euphotic layer sustain local productivity, in turn depleting the layers below. However, the nutrient pathways by which these subeuphotic layers are themselves replenished remain unclear. Using a global, eddy-permitting simulation of ocean physics and biogeochemistry, we quantify nutrient resupply mechanisms along and across density surfaces, including the contribution of eddy-scale motions that are challenging to observe. We find that mesoscale eddies (10 to 100 km) flux nutrients from the shallow flanks of the gyre into the recirculating interior, through time-varying motions along density surfaces. The subeuphotic layers are ultimately replenished in approximately equal contributions by this mesoscale eddy transport and the remineralization of sinking particles. The mesoscale eddy resupply is most important in the lower thermocline for the whole subtropical region but is dominant at all depths within the gyre interior. Subtropical gyre productivity may therefore be sustained by a nutrient relay, where the lateral transport resupplies nutrients to the thermocline and allows vertical exchanges to maintain surface biological production and carbon export.


Asunto(s)
Carbono , Agua de Mar , Nutrientes , Océanos y Mares
2.
EMBO Rep ; 23(4): e51932, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35080333

RESUMEN

Expression of the deubiquitinase USP17 is induced by multiple stimuli, including cytokines (IL-4/6), chemokines (IL-8, SDF1), and growth factors (EGF), and several studies indicate it is required for cell proliferation and migration. However, the mechanisms via which USP17 impacts upon these cellular functions are unclear. Here, we demonstrate that USP17 depletion prevents peripheral lysosome positioning, as well as trafficking of lysosomes to the cell periphery in response to EGF stimulation. Overexpression of USP17 also increases secretion of the lysosomal protease cathepsin D. In addition, USP17 depletion impairs plasma membrane repair in cells treated with the pore-forming toxin streptolysin O, further indicating that USP17 is required for lysosome trafficking to the plasma membrane. Finally, we demonstrate that USP17 can deubiquitinate p62, and we propose that USP17 can facilitate peripheral lysosome trafficking by opposing the E3 ligase RNF26 to untether lysosomes from the ER and facilitate lysosome peripheral trafficking, lysosome protease secretion, and plasma membrane repair.


Asunto(s)
Lisosomas , Membrana Celular/metabolismo , Proliferación Celular , Lisosomas/metabolismo
3.
Proc Natl Acad Sci U S A ; 118(19)2021 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-33941676

RESUMEN

Chronic inflammatory diseases like rheumatoid arthritis are characterized by a deficit in fully functional regulatory T cells. DNA-methylation inhibitors have previously been shown to promote regulatory T cell responses and, in the present study, we evaluated their potential to ameliorate chronic and acute animal models of rheumatoid arthritis. Of the drugs tested, decitabine was the most effective, producing a sustained therapeutic effect that was dependent on indoleamine 2,3-dioxygenase (IDO) and was associated with expansion of induced regulatory T cells, particularly at the site of disease activity. Treatment with decitabine also caused apoptosis of Th1 and Th17 cells in active arthritis in a highly selective manner. The molecular basis for this selectivity was shown to be ENT1, a nucleoside transporter, which facilitates intracellular entry of the drug and is up-regulated on effector T cells during active arthritis. It was further shown that short-term treatment with decitabine resulted in the generation of a population of regulatory T cells that were able to suppress arthritis upon adoptive transfer. In summary, a therapeutic approach using an approved drug is described that treats active inflammatory disease effectively and generates robust regulatory T cells with the IDO-dependent capacity to maintain remission.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Artritis Reumatoide/tratamiento farmacológico , Enfermedades Autoinmunes/tratamiento farmacológico , Decitabina/farmacología , Linfocitos T Reguladores/efectos de los fármacos , Células TH1/efectos de los fármacos , Células Th17/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Apoptosis/inmunología , Artritis Experimental/inmunología , Artritis Experimental/metabolismo , Artritis Reumatoide/inmunología , Artritis Reumatoide/metabolismo , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/metabolismo , Desmetilación del ADN/efectos de los fármacos , Tranportador Equilibrativo 1 de Nucleósido/genética , Tranportador Equilibrativo 1 de Nucleósido/inmunología , Tranportador Equilibrativo 1 de Nucleósido/metabolismo , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Indolamina-Pirrol 2,3,-Dioxigenasa/inmunología , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Masculino , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Noqueados , Inducción de Remisión , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/inmunología , Células TH1/citología , Células TH1/inmunología , Células Th17/citología , Células Th17/inmunología
4.
Pediatr Cardiol ; 45(4): 729-739, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38360919

RESUMEN

Multisystem inflammatory syndrome in children (MIS-C) commonly involves cardiac injury with both systolic and diastolic dysfunction. Left atrial strain (LAS) detects subclinical diastolic dysfunction in adults but is infrequently used in children. We evaluated LAS in MIS-C and the associations with systemic inflammation and cardiac injury. In this retrospective cohort study, LAS parameters [reservoir (LAS-r), conduit (LAS-cd), and contractile (LAS-ct)] obtained from admission echocardiograms of MIS-C patients were compared to healthy controls and between MIS-C patients with and without cardiac injury (BNP > 500 pg/ml or troponin-I > 0.04 ng/ml). Correlation and logistic regression analyses were performed to assess LAS associations with admission inflammatory and cardiac biomarkers. Reliability testing was performed. We identified 118 patients with MIS-C and 20 healthy controls. Median LAS parameters were reduced in MIS-C patients compared to controls (LAS-r: 31.8 vs. 43.1%, p < 0.001; LAS-cd: - 28.8 vs. - 34.5%, p = 0.006; LAS-ct: - 5.2 vs. - 9.3%, p < 0.001) and reduced in MIS-C patients with cardiac injury (n = 59) compared to no injury (n = 59) (LAS-r: 29.6 vs. 35.8%, p = 0.001; LAS-cd: - 26.5 vs. - 30.4%, p = 0.036; LAS-ct: - 4.6 vs. - 9.3%, p = 0.008). A discrete LAS-ct peak was absent in 65 (55%) MIS-C patients but present in all controls (p < 0.001). Procalcitonin correlated strongly with averaged E/e' (r = 0.55, p = 0.001). Moderate correlations were found for ESR and LAS-ct (r = - 0.41, p = 0.007) as well as BNP and LAS-r (r = - 0.39, p < 0.001) and LAS-ct (r = 0.31, p = 0.023). Troponin-I had only weak correlations. Intra-rater reliability was good for all LAS parameters, and inter-rater reliability was good to excellent for LAS-r, and fair for LAS-cd and LAS-ct. LAS analysis, particularly the absence of a LAS-ct peak, was reproducible and may be superior to conventional echocardiographic parameters for detecting diastolic dysfunction in MIS-C. No strain parameters on admission were independently associated with cardiac injury.


Asunto(s)
COVID-19/complicaciones , Síndrome de Respuesta Inflamatoria Sistémica , Troponina I , Disfunción Ventricular Izquierda , Adulto , Niño , Humanos , Estudios Retrospectivos , Reproducibilidad de los Resultados , Inflamación
5.
Pediatr Cardiol ; 45(3): 560-569, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38281215

RESUMEN

Children with COVID-associated multisystem inflammatory syndrome (MIS-C) may develop severe disease. We explored the association of admission echocardiographic and laboratory parameters with MIS-C disease severity. This retrospective, single center study of consecutive MIS-C patients (4/2020-12/2021) excluded those with preexisting cardiomyopathy, congenital heart disease, or prior cardiotoxic therapy. Our hypothesis was that worse admission echocardiographic and laboratory parameters were associated with more severe disease based on vasoactive medication use. Univariable and multivariable logistic regression models assessed the association between vasoactive medication use and baseline variables. Of 118 MIS-C patients, median age was 7.8 years (IQR 4.6, 11.8), 48% received vasoactive medication. Higher admission brain natriuretic peptide [OR 1.07 (95% CI 1.02,1.14), p = 0.019], C-reactive protein [OR 1.08 (1.03,1.14), p = 0.002], troponin [OR 1.05 (1.02,1.1), p = 0.015]; lower left ventricular ejection fraction [LVEF, OR 0.96 (0.92,1), p = 0.042], and worse left atrial reservoir strain [OR 0.96 (0.92,1), p = 0.04] were associated with vasoactive medication use. Only higher CRP [OR 1.07 (1.01, 1.11), p = 0.034] and lower LVEF [0.91 (0.84,0.98), p = 0.015] remained independently significant. Among those with normal admission LVEF (78%, 92/118), 43% received vasoactive medication and only higher BNP [OR 1.09 (1.02,1.19), p = 0.021 per 100 pg/mL] and higher CRP [OR 1.07 (1.02,1.14), p = 0.013] were associated with use of vasoactive medication. Nearly half of all children admitted for MIS-C subsequently received vasoactive medication, including those admitted with a normal LVEF. Similarly, admission strain parameters were not discriminatory. Laboratory markers of systemic inflammation and cardiac injury may better predict early MIS-C disease severity.


Asunto(s)
Ecocardiografía , Función Ventricular Izquierda , Niño , Humanos , Volumen Sistólico , Estudios Retrospectivos , Péptido Natriurético Encefálico , Gravedad del Paciente
6.
Ann Gen Psychiatry ; 23(1): 1, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172807

RESUMEN

INTRODUCTION: Weight gain in the months/years after diagnosis/treatment of severe enduring mental illness (SMI) is a major predictor of future diabetes, dysmetabolic profile and increased risk of cardiometabolic diseases. There is limited data on the longer-term profile of weight change in people with a history of SMI and how this may differ between individuals. We here report a retrospective study on weight change over the 5 years following an SMI diagnosis in Greater Manchester UK, an ethnically and culturally diverse community, with particular focus on comparing non-affective psychosis (NAP) vs affective psychosis (AP) diagnoses. METHODS: We undertook an anonymised search in the Greater Manchester Care Record (GMCR). We reviewed the health records of anyone who had been diagnosed for the first time with first episode psychosis, schizophrenia, schizoaffective disorder, delusional disorder (non-affective psychosis = NAP) or affective psychosis (AP). We analysed body mass index (BMI) change in the 5-year period following the first prescription of antipsychotic medication. All individuals had taken an antipsychotic agent for at least 3 months. The 5-year follow-up point was anywhere between 2003 and 2023. RESULTS: We identified 9125 people with the diagnoses above. NAP (n = 5618; 37.3% female) mean age 49.9 years; AP (n = 4131; 60.5% female) mean age 48.7 years. 27.0% of NAP were of non-White ethnicity vs 17.8% of AP individuals. A higher proportion of people diagnosed with NAP were in the highest quintile of social disadvantage 52.4% vs 39.5% for AP. There were no significant differences in baseline BMI profile. In a subsample with HbA1c data (n = 2103), mean HbA1c was higher in NAP at baseline (40.4 mmol/mol in NAP vs 36.7 mmol/mol for AP). At 5-year follow-up, there was similarity in both the overall % of individuals in the obese ≥ 30 kg/m2 category (39.8% NAP vs 39.7% AP), and % progressing from a normal healthy BMI transitioned to obese/overweight BMI (53.6% of NAP vs 55.6% with AP). 43.7% of those NAP with normal BMI remained at a healthy BMI vs 42.7% with AP. At 5-year follow-up for NAP, 83.1% of those with BMI ≥ 30 kg/m2 stayed in this category vs 81.5% of AP. CONCLUSION: The results of this real-world longitudinal cohort study suggest that the changes in BMI with treatment of non-affective psychosis vs bipolar disorder are not significantly different, while 43% maintain a healthy weight in the first 5 years following antipsychotic prescription.

7.
J Biol Chem ; 298(8): 102151, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35718063

RESUMEN

cAMP and antimicrobial susceptibility in mycobacteriaAntimicrobial tolerance, the ability to survive exposure to antimicrobials via transient nonspecific means, promotes the development of antimicrobial resistance (AMR). The study of the molecular mechanisms that result in antimicrobial tolerance is therefore essential for the understanding of AMR. In gram-negative bacteria, the second messenger molecule 3'',5''-cAMP has been previously shown to be involved in AMR. In mycobacteria, however, the role of cAMP in antimicrobial tolerance has been difficult to probe due to its particular complexity. In order to address this difficulty, here, through unbiased biochemical approaches consisting in the fractionation of clear protein lysate from a mycobacterial strain deleted for the known cAMP phosphodiesterase (Rv0805c) combined with mass spectrometry techniques, we identified a novel cyclic nucleotide-degrading phosphodiesterase enzyme (Rv1339) and developed a system to significantly decrease intracellular cAMP levels through plasmid expression of Rv1339 using the constitutive expression system, pVV16. In Mycobacterium smegmatis mc2155, we demonstrate that recombinant expression of Rv1339 reduced cAMP levels threefold and resulted in altered gene expression, impaired bioenergetics, and a disruption in peptidoglycan biosynthesis leading to decreased tolerance to antimicrobials that target cell wall synthesis such as ethambutol, D-cycloserine, and vancomycin. This work increases our understanding of the role of cAMP in mycobacterial antimicrobial tolerance, and our observations suggest that nucleotide signaling may represent a new target for the development of antimicrobial therapies.


Asunto(s)
Antiinfecciosos , Farmacorresistencia Bacteriana , Mycobacterium smegmatis , Hidrolasas Diéster Fosfóricas , Antiinfecciosos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Pared Celular/efectos de los fármacos , AMP Cíclico , Mycobacterium smegmatis/enzimología , Mycobacterium smegmatis/genética , Hidrolasas Diéster Fosfóricas/genética , Hidrolasas Diéster Fosfóricas/metabolismo
8.
J Neurochem ; 2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38102897

RESUMEN

Although the central nervous system (CNS) and immune system were regarded as independent entities, it is now clear that immune system cells can influence the CNS, and neuroglial activity influences the immune system. Despite the many clinical implications for this 'neuroimmune interface', its detailed operation at the molecular level remains unclear. This narrative review focuses on the metabolism of tryptophan along the kynurenine pathway, since its products have critical actions in both the nervous and immune systems, placing it in a unique position to influence neuroimmune communication. In particular, since the kynurenine pathway is activated by pro-inflammatory mediators, it is proposed that physical and psychological stressors are the stimuli of an organismal protective reflex, with kynurenine metabolites as the effector arm co-ordinating protective neural and immune system responses. After a brief review of the neuroimmune interface, the general perception of tryptophan metabolism along the kynurenine pathway is expanded to emphasize this environmentally driven perspective. The initial enzymes in the kynurenine pathway include indoleamine-2,3-dioxygenase (IDO1), which is induced by tissue damage, inflammatory mediators or microbial products, and tryptophan-2,3-dioxygenase (TDO), which is induced by stress-induced glucocorticoids. In the immune system, kynurenic acid modulates leucocyte differentiation, inflammatory balance and immune tolerance by activating aryl hydrocarbon receptors and modulates pain via the GPR35 protein. In the CNS, quinolinic acid activates N-methyl-D-aspartate (NMDA)-sensitive glutamate receptors, whereas kynurenic acid is an antagonist: the balance between glutamate, quinolinic acid and kynurenic acid is a significant regulator of CNS function and plasticity. The concept of kynurenine and its metabolites as mediators of a reflex coordinated protection against stress helps to understand the variety and breadth of their activity. It should also help to understand the pathological origin of some psychiatric and neurodegenerative diseases involving the immune system and CNS, facilitating the development of new pharmacological strategies for treatment.

9.
PLoS Med ; 20(9): e1004289, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37751419

RESUMEN

BACKGROUND: There are known socioeconomic inequalities in annual seasonal influenza (flu) vaccine uptake. The Coronavirus Disease 2019 (COVID-19) pandemic was associated with multiple factors that may have affected flu vaccine uptake, including widespread disruption to healthcare services, changes to flu vaccination eligibility and delivery, and increased public awareness and debate about vaccination due to high-profile COVID-19 vaccination campaigns. However, to the best of our knowledge, no existing studies have investigated the consequences for inequalities in flu vaccine uptake, so we aimed to investigate whether socioeconomic inequalities in flu vaccine uptake have widened since the onset of the COVID-19 pandemic. METHODS AND FINDINGS: We used deidentified data from electronic health records for a large city region (Greater Manchester, population 2.8 million), focusing on 3 age groups eligible for National Health Service (NHS) flu vaccination: preschool children (age 2 to 3 years), primary school children (age 4 to 9 years), and older adults (age 65 years plus). The sample population varied between 418,790 (2015/16) and 758,483 (2021/22) across each vaccination season. We estimated age-adjusted neighbourhood-level income deprivation-related inequalities in flu vaccine uptake using Cox proportional hazards models and the slope index of inequality (SII), comparing 7 flu vaccination seasons (2015/16 to 2021/22). Among older adults, the SII (i.e., the gap in uptake between the least and most income-deprived areas) doubled over the 7 seasons from 8.48 (95% CI [7.91,9.04]) percentage points to 16.91 (95% CI [16.46,17.36]) percentage points, with approximately 80% of this increase occurring during the pandemic. Before the pandemic, income-related uptake gaps were wider among children, ranging from 15.59 (95% CI [14.52,16.67]) percentage points to 20.07 (95% CI [18.94,21.20]) percentage points across age groups and vaccination seasons. Among preschool children, the uptake gap increased in 2020/21 to 25.25 (95% CI [24.04,26.45]) percentage points, before decreasing to 20.86 (95% CI [19.65,22.05]) percentage points in 2021/22. Among primary school children, inequalities increased in both pandemic years to reach 30.27 (95% CI [29.58,30.95]) percentage points in 2021/22. Although vaccine uptake increased during the pandemic, disproportionately larger increases in uptake in less deprived areas created wider inequalities in all age groups. The main limitation of our approach is the use of a local dataset, which may limit generalisability to other geographical settings. CONCLUSIONS: The COVID-19 pandemic led to increased inequalities in flu vaccine uptake, likely due to changes in demand for vaccination, new delivery models, and disruptions to healthcare and schooling. It will be important to investigate the causes of these increased inequalities and to examine whether these increased inequalities also occurred in the uptake of other routine vaccinations. These new wider inequalities in flu vaccine uptake may exacerbate inequalities in flu-related morbidity and mortality.


Asunto(s)
COVID-19 , Vacunas contra la Influenza , Gripe Humana , Preescolar , Humanos , Niño , Anciano , Vacunas contra la Influenza/uso terapéutico , Pandemias/prevención & control , Estudios de Cohortes , Vacunas contra la COVID-19 , Medicina Estatal , COVID-19/epidemiología , COVID-19/prevención & control , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Inglaterra/epidemiología , Escolaridad
10.
HIV Med ; 24(9): 979-989, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37088964

RESUMEN

BACKGROUND: People living with HIV have been shown to have an increased risk of invasive meningococcal disease. In some countries, meningococcal vaccines are now routinely recommended to all people living with HIV, but no study has yet assessed the immunogenicity and safety of a meningococcal serogroup B vaccine or the co-administration of a MenB and MenACWY vaccine in people living with HIV. METHODS: This phase IV open-label clinical trial investigated the immunogenicity and safety of two doses of a four-component recombinant protein-based MenB vaccine (4CMenB) and a quadrivalent conjugate polysaccharide MenACWY vaccine (MenACWY-CRM197) given 1 month apart in a population of people living with HIV. Immunogenicity analysis was performed before vaccination and 1 month after the second doses of 4CMenB and MenACWY. Primary outcome measures were serum bactericidal assay geometric mean titres against three MenB reference strains at baseline and 1 month post vaccination, the proportion of participants achieving a putative protective titre of ≥4, and the proportion of participants with a ≥4-fold rise in titre from baseline. Secondary outcome measures were serum bactericidal assay geometric mean titres against MenA, C, W, and Y reference strains at baseline and 1 month post vaccination, the proportion achieving a putative protective titre of ≥8, and the proportion with a ≥4-fold rise in titre from baseline. Safety outcomes were solicited and unsolicited adverse events in the 7 days following vaccination. The trial was registered with clinicaltrials.gov (NCT03682939). FINDINGS: In total, 55 participants aged 20-45 years were enrolled. All participants (100%; 95% confidence interval [CI] 93-100) achieved putative protective titres for two of the three MenB strains and for MenA, W, and Y. A total of 98% (95% CI 89-100) achieved a protective titre for the third MenB strain and 94% (95% CI 83-99) for MenC. No serious adverse events were reported. INTERPRETATION: 4CMenB and MenACWY were immunogenic and well-tolerated in a population of people living with HIV 1 month after two doses.


Asunto(s)
Infecciones por VIH , Infecciones Meningocócicas , Vacunas Meningococicas , Humanos , Vacunas Meningococicas/efectos adversos , Infecciones Meningocócicas/prevención & control , Infecciones Meningocócicas/inducido químicamente , Vacunas Combinadas , Proteínas Recombinantes
11.
J Autoimmun ; 138: 103031, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37229811

RESUMEN

The aim of this study was to assess the L-type amino acid transporter-1 (LAT1) as a possible therapeutic target for rheumatoid arthritis (RA). Synovial LAT1 expression in RA was monitored by immunohistochemistry and transcriptomic datasets. The contribution of LAT1 to gene expression and immune synapse formation was assessed by RNA-sequencing and total internal reflection fluorescent (TIRF) microscopy, respectively. Mouse models of RA were used to assess the impact of therapeutic targeting of LAT1. LAT1 was strongly expressed by CD4+ T cells in the synovial membrane of people with active RA and the level of expression correlated with levels of ESR and CRP as well as DAS-28 scores. Deletion of LAT1 in murine CD4+ T cells inhibited the development of experimental arthritis and prevented the differentiation of CD4+ T cells expressing IFN-γ and TNF-α, without affecting regulatory T cells. LAT1 deficient CD4+ T cells demonstrated reduced transcription of genes associated with TCR/CD28 signalling, including Akt1, Akt2, Nfatc2, Nfkb1 and Nfkb2. Functional studies using TIRF microscopy revealed a significant impairment of immune synapse formation with reduced recruitment of CD3ζ and phospho-tyrosine signalling molecules in LAT1 deficient CD4+ T cells from the inflamed joints but not the draining lymph nodes of arthritic mice. Finally, it was shown that a small molecule LAT1 inhibitor, currently undergoing clinical trials in man, was highly effective in treating experimental arthritis in mice. It was concluded that LAT1 plays a critical role in activation of pathogenic T cell subsets under inflammatory conditions and represents a promising new therapeutic target for RA.


Asunto(s)
Artritis Experimental , Artritis Reumatoide , Ratones , Animales , Membrana Sinovial , Subgrupos de Linfocitos T , Linfocitos T Reguladores/metabolismo , Transducción de Señal , Artritis Experimental/genética , Linfocitos T CD4-Positivos
12.
Circ Res ; 129(2): 280-295, 2021 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-33975450
13.
Philos Trans A Math Phys Eng Sci ; 381(2249): 20220062, 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37150198

RESUMEN

The effect of the Southern Ocean on global climate change is assessed using Earth system model projections following an idealized 1% annual rise in atmospheric CO2. For this scenario, the Southern Ocean plays a significant role in sequestering heat and anthropogenic carbon, accounting for 40% ± 5% of heat uptake and 44% ± 2% of anthropogenic carbon uptake over the global ocean (with the Southern Ocean defined as south of 36°S). This Southern Ocean fraction of global heat uptake is however less than in historical scenarios with marked hemispheric contrasts in radiative forcing. For this idealized scenario, inter-model differences in global and Southern Ocean heat uptake are strongly affected by physical feedbacks, especially cloud feedbacks over the globe and surface albedo feedbacks from sea-ice loss in high latitudes, through the top-of-the-atmosphere energy balance. The ocean carbon response is similar in most models with carbon storage increasing from rising atmospheric CO2, but weakly decreasing from climate change with competing ventilation and biological contributions over the Southern Ocean. The Southern Ocean affects a global climate metric, the transient climate response to emissions, accounting for 28% of its thermal contribution through its physical climate feedbacks and heat uptake, and so affects inter-model differences in meeting warming targets. This article is part of a discussion meeting issue 'Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities'.

14.
Cochrane Database Syst Rev ; 12: CD011793, 2023 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-38054555

RESUMEN

BACKGROUND: Aortic valve disease is a common condition easily treatable with cardiac surgery. This is conventionally performed by opening the sternum ('median sternotomy') and replacing the valve under cardiopulmonary bypass. Median sternotomy is well tolerated, but as less invasive options become available, the efficacy of limited incisions has been called into question. In particular, the effects of reducing the visibility and surgical access have raised safety concerns with regard to the placement of cannulae, venting of the heart, epicardial wire placement, and de-airing of the heart at the end of the procedure. These difficulties may increase operating times, affecting outcome. The benefits of smaller incisions are thought to include decreased pain; improved respiratory mechanics; reductions in wound infections, bleeding, and need for transfusion; shorter intensive care stay; better cosmesis; and a quicker return to normal activity. This is an update of a Cochrane review first published in 2017, with seven new studies. OBJECTIVES: To assess the effects of minimally invasive aortic valve replacement via a limited sternotomy versus conventional aortic valve replacement via median sternotomy in people with aortic valve disease requiring surgical replacement. SEARCH METHODS: We performed searches of CENTRAL, MEDLINE and Embase from inception to August 2021, with no language limitations. We also searched two clinical trials registries and manufacturers' websites. We reviewed references of primary studies to identify any further studies of relevance. SELECTION CRITERIA: We included randomised controlled trials comparing aortic valve replacement via a median sternotomy versus aortic valve replacement via a limited sternotomy. We excluded trials that performed other minimally invasive incisions such as mini-thoracotomies, port access, transapical, transfemoral or robotic procedures. Although some well-conducted prospective and retrospective case-control and cohort studies exist, these were not included in this review. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial papers to extract data, assess quality, and identify risk of bias. A third review author provided arbitration where required. We determined the certainty of evidence using the GRADE methodology and summarised results of patient-relevant outcomes in a summary of findings table. MAIN RESULTS: The review included 14 trials with 1395 participants. Most studies had at least two domains at high risk of bias. We analysed 14 outcomes investigating the effects of minimally invasive limited upper hemi-sternotomy on aortic valve replacement as compared to surgery performed via full median sternotomy. Upper hemi-sternotomy may have little to no effect on mortality versus full median sternotomy (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.45 to 1.94; 10 studies, 985 participants; low-certainty evidence). Upper hemi-sternotomy for aortic valve replacement may increase cardiopulmonary bypass time slightly, although the evidence is very uncertain (mean difference (MD) 10.63 minutes, 95% CI 3.39 to 17.88; 10 studies, 1043 participants; very low-certainty evidence) and may increase aortic cross-clamp time slightly (MD 6.07 minutes, 95% CI 0.79 to 11.35; 12 studies, 1235 participants; very low-certainty evidence), although the evidence is very uncertain. Most studies had at least two domains at high risk of bias. Postoperative blood loss was probably lower in the upper hemi-sternotomy group (MD -153 mL, 95% CI -246 to -60; 8 studies, 767 participants; moderate-certainty evidence). Low-certainty evidence suggested that there may be no change in pain scores by upper hemi-sternotomy (standardised mean difference (SMD) -0.19, 95% CI -0.43 to 0.04; 5 studies, 649 participants). Upper hemi-sternotomy may result in little to no difference in quality of life (MD 0.03 higher, 95% CI 0 to 0.06 higher; 4 studies, 624 participants; low-certainty evidence). Two studies reporting index admission costs concluded that limited sternotomy may be more costly at index admission in the UK National Health Service (MD 1190 GBP more, 95% CI 420 GBP to 1970 GBP, 2 studies, 492 participants; low-certainty evidence). AUTHORS' CONCLUSIONS: The evidence was of very low to moderate certainty. Sample sizes were small and underpowered to demonstrate differences in some outcomes. Clinical heterogeneity was also noted. Considering these limitations, there may be little to no effect on mortality. Differences in extracorporeal support times are uncertain, comparing upper hemi-sternotomy to full sternotomy for aortic valve replacement. Before widespread adoption of the minimally invasive approach can be recommended, there is a need for a well-designed and adequately powered prospective randomised controlled trial. Such a study would benefit from also performing a robust cost analysis. Growing patient preference for minimally invasive techniques merits thorough quality of life analyses to be included as end points, as well as quantitative measures of physiological reserve.


Asunto(s)
Enfermedad de la Válvula Aórtica , Herida Quirúrgica , Humanos , Válvula Aórtica/cirugía , Esternotomía/efectos adversos , Calidad de Vida , Estudios Prospectivos , Estudios Retrospectivos , Medicina Estatal , Dolor , Ensayos Clínicos Controlados Aleatorios como Asunto
15.
Am J Respir Crit Care Med ; 205(7): 769-782, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35073247

RESUMEN

Rationale: Although the cysteine protease cathepsin S has been implicated in the pathogenesis of several inflammatory lung diseases, its role has not been examined in the context of acute respiratory distress syndrome, a condition that still lacks specific and effective pharmacological treatments. Objectives: To characterize the status of cathepsin S in acute lung inflammation and examine the role of cathepsin S in disease pathogenesis. Methods: Human and mouse model BAL fluid samples were analyzed for the presence and activity of cathepsin S and its endogenous inhibitors. Recombinant cathepsin S was instilled directly into the lungs of mice. The effects of cathepsin S knockout and pharmacological inhibition were examined in two models of acute lung injury. Protease-activated receptor-1 antagonism was used to test a possible mechanism for cathepsin S-mediated inflammation. Measurements and Main Results: Pulmonary cathepsin S concentrations and activity were elevated in acute respiratory distress syndrome, a phenotype possibly exacerbated by the loss of the endogenous antiprotease cystatin SN. Direct cathepsin S instillation into the lungs induced key pathologies of acute respiratory distress syndrome, including neutrophilia and alveolar leakage. Conversely, in murine models of acute lung injury, genetic knockdown and prophylactic or therapeutic inhibition of cathepsin S reduced neutrophil recruitment and protein leakage. Cathepsin S may partly mediate its pathogenic effects via protease-activated receptor-1, because antagonism of this receptor abrogated cathepsin S-induced airway inflammation. Conclusions: Cathepsin S contributes to acute lung injury and may represent a novel therapeutic target for acute respiratory distress syndrome.


Asunto(s)
Neumonía , Síndrome de Dificultad Respiratoria , Animales , Líquido del Lavado Bronquioalveolar , Catepsinas , Modelos Animales de Enfermedad , Humanos , Pulmón/patología , Ratones
16.
Pediatr Cardiol ; 44(3): 618-623, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35902413

RESUMEN

The Pediatric Heart Network (PHN) trial showed similar efficacy of ß-blockers (BB) and angiotensin receptor blockers (ARB) for aortic root dilation in Marfan syndrome, but the impact on prescription practices is unknown. We hypothesized BB and ARB prescriptions would increase after the trial results were published (2014). Prescription data (2007-2016) were obtained from outpatient encounters (IBM Marketscan) for Marfan syndrome patients (6 months-25 years old). Excluding 2014 as a washout period, we analyzed two intervals: 2007-2013 and 2015-2016. Medication categories included BB, ARB, angiotensin converting enzyme inhibitors (ACEI), combination (BB/ARB and/or BB/ACEI), and no drug. Interrupted time-series analysis assessed immediate level change after publication and change in slope for the trend pre- and post-publication. Odds ratios (OR) and 95% confidence intervals from logistic regressions and generalized estimating equation methods accounted for correlation of prescriptions within patients. In 1499 patients (age 14.1 ± 6.1 years, 59% female) seen 2007-2013, BB trended lower [OR 0.91 (0.89, 0.93), p < 0.001] and ARB trended higher [OR 1.12 (1.07, 1.18), p < 0.001], while combination, ACEI, and no drug remained stable. This trend persisted, but was not significant, for BB [OR 0.54 (0.27, 1.08), p = 0.37] and ARB [OR 1.91 (0.55, 6.69), p = 0.31] in 2015-2016. Combination, ACEI, and no drug remained similar. In short term follow-up, changes in prescription practices following publication of the PHN trial were not statistically significant. This may be due to a change seen prior to publication with early adoption of ARBs that was maintained after confirmation of their effectiveness.


Asunto(s)
Losartán , Síndrome de Marfan , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Adulto Joven , Antagonistas Adrenérgicos beta/uso terapéutico , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Antagonistas de Receptores de Angiotensina/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Atenolol/uso terapéutico , Losartán/uso terapéutico , Síndrome de Marfan/tratamiento farmacológico , Prescripciones
17.
Pediatr Cardiol ; 44(8): 1691-1701, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37382636

RESUMEN

The Pediatric Heart Network's Fontan Udenafil Exercise Longitudinal (FUEL) Trial (Mezzion Pharma Co. Ltd., NCT02741115) demonstrated improvements in some measures of exercise capacity and in the myocardial performance index following 6 months of treatment with udenafil (87.5 mg twice daily). In this post hoc analysis, we evaluate whether subgroups within the population experienced a differential effect on exercise performance in response to treatment. The effect of udenafil on exercise was evaluated within subgroups defined by baseline characteristics, including peak oxygen consumption (VO2), serum brain-type natriuretic peptide level, weight, race, gender, and ventricular morphology. Differences among subgroups were evaluated using ANCOVA modeling with fixed factors for treatment arm and subgroup and the interaction between treatment arm and subgroup. Within-subgroup analyses demonstrated trends toward quantitative improvements in peak VO2, work rate at the ventilatory anaerobic threshold (VAT), VO2 at VAT, and ventilatory efficiency (VE/VCO2) for those randomized to udenafil compared to placebo in nearly all subgroups. There was no identified differential response to udenafil based on baseline peak VO2, baseline BNP level, weight, race and ethnicity, gender, or ventricular morphology, although participants in the lowest tertile of baseline peak VO2 trended toward larger improvements. The absence of a differential response across subgroups in response to treatment with udenafil suggests that the treatment benefit may not be restricted to specific sub-populations. Further work is warranted to confirm the potential benefit of udenafil and to evaluate the long-term tolerability and safety of treatment and to determine the impact of udenafil on the development of other morbidities related to the Fontan circulation.Trial Registration NCT0274115.


Asunto(s)
Consumo de Oxígeno , Sulfonamidas , Humanos , Niño , Sulfonamidas/uso terapéutico , Ejercicio Físico , Pirimidinas/uso terapéutico , Prueba de Esfuerzo , Tolerancia al Ejercicio
18.
Cardiol Young ; 33(10): 1813-1818, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36200342

RESUMEN

BACKGROUND: Published guidelines for sports restriction for children with a bicuspid aortic valve remain controversial. We sought to describe practice variation and factors influencing sports restrictions in these children. METHODS: This retrospective single-centre study included children (7-18 years old) with an isolated bicuspid aortic valve at baseline from 1 January, 2005 to 31 December, 2014. Sports restrictions, factors potentially influencing decision-making, and outcomes were collected. Descriptive statistics and multivariable mixed-effects logistic regression models were performed with providers and patients as random effects. Provider variation was estimated using intraclass correlation coefficients. Odds ratios, 95% confidence intervals, and p-values were reported from the models. RESULTS: In 565 encounters (253 children; 34 providers), 41% recommended no sports restrictions, 40% recommended high-static and high-dynamic restrictions, and 19% had no documented recommendations. Based on published guidelines, 22% of children were inappropriately restricted while 30% were not appropriately restricted. The paediatric cardiology provider contributed to 37% of observed practice variation (p < 0.001). Sports restriction was associated with older age, males, greater ascending aorta z-score, and shorter follow-up interval. There were no aortic dissections or deaths and one cardiac intervention. CONCLUSION: Physicians frequently fail to document sports restrictions for children with a bicuspid aortic valve, and documented recommendations often conflict with published guidelines. Despite this, no adverse outcomes occurred. Providers accounted for a significant proportion of the variation in sports restrictions. Further research to provide evidence-based guidelines may improve provider compliance with activity recommendations in this population.


Asunto(s)
Enfermedad de la Válvula Aórtica Bicúspide , Enfermedades de las Válvulas Cardíacas , Masculino , Humanos , Niño , Adolescente , Válvula Aórtica , Enfermedades de las Válvulas Cardíacas/complicaciones , Estudios Retrospectivos , Aorta
19.
Genes Dev ; 29(5): 483-8, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25737277

RESUMEN

We performed a genome-scale shRNA screen for modulators of B-cell leukemia progression in vivo. Results from this work revealed dramatic distinctions between the relative effects of shRNAs on the growth of tumor cells in culture versus in their native microenvironment. Specifically, we identified many "context-specific" regulators of leukemia development. These included the gene encoding the zinc finger protein Phf6. While inactivating mutations in PHF6 are commonly observed in human myeloid and T-cell malignancies, we found that Phf6 suppression in B-cell malignancies impairs tumor progression. Thus, Phf6 is a "lineage-specific" cancer gene that plays opposing roles in developmentally distinct hematopoietic malignancies.


Asunto(s)
Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Leucemia/genética , Linaje de la Célula , Proliferación Celular/genética , Genoma Humano/genética , Humanos , Leucemia/fisiopatología , Mutación/genética , ARN Interferente Pequeño/genética , Proteínas Represoras
20.
Soc Sci Res ; 109: 102802, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36470637

RESUMEN

Social scientists are often interested in seeing how the estimated effects of variables change once other variables are controlled for. For example, a simple analysis may reveal that income differs by race - but why does it differ? To answer such a question, a researcher might estimate a model where race is the only independent variable, and then add variables such as education to subsequent models. If the original estimated effect of race declines, this may be because race affects education, which in turn affects income. What is not universally realized is that the interpretation of such nested models can be problematic when logit or probit techniques are employed with binary dependent variables. Naïve comparisons of coefficients between models can indicate differences where none exist, hide differences that do exist, and even show differences in the opposite direction of what actually exists. We discuss why problems occur and illustrate their potential consequences. Proposed solutions, such as Linear Probability Models, Y-standardization, the Karlson/Holm/Breen method, and marginal effects, are explained and evaluated.


Asunto(s)
Proyectos de Investigación , Humanos , Modelos Logísticos
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