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1.
Nature ; 599(7883): 120-124, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34646011

RESUMEN

Antibiotics are used to fight pathogens but also target commensal bacteria, disturbing the composition of gut microbiota and causing dysbiosis and disease1. Despite this well-known collateral damage, the activity spectrum of different antibiotic classes on gut bacteria remains poorly characterized. Here we characterize further 144 antibiotics from a previous screen of more than 1,000 drugs on 38 representative human gut microbiome species2. Antibiotic classes exhibited distinct inhibition spectra, including generation dependence for quinolones and phylogeny independence for ß-lactams. Macrolides and tetracyclines, both prototypic bacteriostatic protein synthesis inhibitors, inhibited nearly all commensals tested but also killed several species. Killed bacteria were more readily eliminated from in vitro communities than those inhibited. This species-specific killing activity challenges the long-standing distinction between bactericidal and bacteriostatic antibiotic classes and provides a possible explanation for the strong effect of macrolides on animal3-5 and human6,7 gut microbiomes. To mitigate this collateral damage of macrolides and tetracyclines, we screened for drugs that specifically antagonized the antibiotic activity against abundant Bacteroides species but not against relevant pathogens. Such antidotes selectively protected Bacteroides species from erythromycin treatment in human-stool-derived communities and gnotobiotic mice. These findings illluminate the activity spectra of antibiotics in commensal bacteria and suggest strategies to circumvent their adverse effects on the gut microbiota.


Asunto(s)
Antibacterianos/efectos adversos , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Microbioma Gastrointestinal/efectos de los fármacos , Animales , Antibacterianos/clasificación , Bacterias/clasificación , Bacterias Anaerobias/efectos de los fármacos , Bacteroides/efectos de los fármacos , Clostridioides difficile/efectos de los fármacos , Dicumarol/farmacología , Eritromicina/farmacología , Heces/microbiología , Femenino , Vida Libre de Gérmenes , Humanos , Macrólidos/farmacología , Masculino , Ratones , Microbiota/efectos de los fármacos , Simbiosis/efectos de los fármacos , Tetraciclinas/farmacología
2.
Nat Methods ; 20(12): 2000-2010, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37996754

RESUMEN

During animal development, embryos undergo complex morphological changes over time. Differences in developmental tempo between species are emerging as principal drivers of evolutionary novelty, but accurate description of these processes is very challenging. To address this challenge, we present here an automated and unbiased deep learning approach to analyze the similarity between embryos of different timepoints. Calculation of similarities across stages resulted in complex phenotypic fingerprints, which carry characteristic information about developmental time and tempo. Using this approach, we were able to accurately stage embryos, quantitatively determine temperature-dependent developmental tempo, detect naturally occurring and induced changes in the developmental progression of individual embryos, and derive staging atlases for several species de novo in an unsupervised manner. Our approach allows us to quantify developmental time and tempo objectively and provides a standardized way to analyze early embryogenesis.


Asunto(s)
Aprendizaje Profundo , Animales , Desarrollo Embrionario , Evolución Biológica , Temperatura
3.
Nat Methods ; 20(6): 815-823, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37156842

RESUMEN

Evolutionarily conserved signaling pathways are essential for early embryogenesis, and reducing or abolishing their activity leads to characteristic developmental defects. Classification of phenotypic defects can identify the underlying signaling mechanisms, but this requires expert knowledge and the classification schemes have not been standardized. Here we use a machine learning approach for automated phenotyping to train a deep convolutional neural network, EmbryoNet, to accurately identify zebrafish signaling mutants in an unbiased manner. Combined with a model of time-dependent developmental trajectories, this approach identifies and classifies with high precision phenotypic defects caused by loss of function of the seven major signaling pathways relevant for vertebrate development. Our classification algorithms have wide applications in developmental biology and robustly identify signaling defects in evolutionarily distant species. Furthermore, using automated phenotyping in high-throughput drug screens, we show that EmbryoNet can resolve the mechanism of action of pharmaceutical substances. As part of this work, we freely provide more than 2 million images that were used to train and test EmbryoNet.


Asunto(s)
Aprendizaje Profundo , Animales , Pez Cebra/genética , Redes Neurales de la Computación , Algoritmos , Fenotipo , Transducción de Señal
4.
Value Health ; 27(6): 692-701, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38871437

RESUMEN

This ISPOR Good Practices report provides a framework for assessing the suitability of electronic health records data for use in health technology assessments (HTAs). Although electronic health record (EHR) data can fill evidence gaps and improve decisions, several important limitations can affect its validity and relevance. The ISPOR framework includes 2 components: data delineation and data fitness for purpose. Data delineation provides a complete understanding of the data and an assessment of its trustworthiness by describing (1) data characteristics; (2) data provenance; and (3) data governance. Fitness for purpose comprises (1) data reliability items, ie, how accurate and complete the estimates are for answering the question at hand and (2) data relevance items, which assess how well the data are suited to answer the particular question from a decision-making perspective. The report includes a checklist specific to EHR data reporting: the ISPOR SUITABILITY Checklist. It also provides recommendations for HTA agencies and policy makers to improve the use of EHR-derived data over time. The report concludes with a discussion of limitations and future directions in the field, including the potential impact from the substantial and rapid advances in the diffusion and capabilities of large language models and generative artificial intelligence. The report's immediate audiences are HTA evidence developers and users. We anticipate that it will also be useful to other stakeholders, particularly regulators and manufacturers, in the future.


Asunto(s)
Lista de Verificación , Registros Electrónicos de Salud , Evaluación de la Tecnología Biomédica , Registros Electrónicos de Salud/normas , Humanos , Reproducibilidad de los Resultados , Comités Consultivos , Toma de Decisiones
5.
Hereditas ; 161(1): 14, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38685093

RESUMEN

BACKGROUND: Nicotinamide phosphoribosyltransferase (Nampt) is required for recycling NAD+ in numerous cellular contexts. Morpholino-based knockdown of zebrafish nampt-a has been shown to cause abnormal development and defective hematopoiesis concomitant with decreased NAD+ levels. However, surprisingly, nampt-a mutant zebrafish were recently found to be viable, suggesting a discrepancy between the phenotypes in knockdown and knockout conditions. Here, we address this discrepancy by directly comparing loss-of-function approaches that result in identical defective transcripts in morphants and mutants. RESULTS: Using CRISPR/Cas9-mediated mutagenesis, we generated nampt-a mutant lines that carry the same mis-spliced mRNA as nampt-a morphants. Despite reduced NAD+ levels and perturbed expression of specific blood markers, nampt-a mutants did not display obvious developmental defects and were found to be viable. In contrast, injection of nampt-a morpholinos into wild-type or mutant nampt-a embryos caused aberrant phenotypes. Moreover, nampt-a morpholinos caused additional reduction of blood-related markers in nampt-a mutants, suggesting that the defects observed in nampt-a morphants can be partially attributed to off-target effects of the morpholinos. CONCLUSIONS: Our findings show that zebrafish nampt-a mutants are viable despite reduced NAD+ levels and a perturbed hematopoietic gene expression program, indicating strong robustness of primitive hematopoiesis during early embryogenesis.


Asunto(s)
Hematopoyesis , Nicotinamida Fosforribosiltransferasa , Pez Cebra , Animales , Pez Cebra/genética , Nicotinamida Fosforribosiltransferasa/genética , Hematopoyesis/genética , Mutación , Proteínas de Pez Cebra/genética , Fenotipo , Sistemas CRISPR-Cas , NAD/metabolismo , Técnicas de Silenciamiento del Gen , Morfolinos/genética
6.
Int J Mol Sci ; 25(3)2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38338655

RESUMEN

Trypsin-like serine proteases are involved in many important physiological processes like blood coagulation and remodeling of the extracellular matrix. On the other hand, they are also associated with pathological conditions. The urokinase-pwlasminogen activator (uPA), which is involved in tissue remodeling, can increase the metastatic behavior of various cancer types when overexpressed and dysregulated. Another member of this protease class that received attention during the SARS-CoV 2 pandemic is TMPRSS2. It is a transmembrane serine protease, which enables cell entry of the coronavirus by processing its spike protein. A variety of different inhibitors have been published against both proteases. However, the selectivity over other trypsin-like serine proteases remains a major challenge. In the current study, we replaced the arginine moiety at the P1 site of peptidomimetic inhibitors with different bioisosteres. Enzyme inhibition studies revealed that the phenylguanidine moiety in the P1 site led to strong affinity for TMPRSS2, whereas the cyclohexylguanidine derivate potently inhibited uPA. Both inhibitors exhibited high selectivity over other structurally similar and physiologically important proteases.


Asunto(s)
Peptidomiméticos , Inhibidores de Serina Proteinasa , Activador de Plasminógeno de Tipo Uroquinasa , Ligandos , Péptido Hidrolasas , Peptidomiméticos/química , Peptidomiméticos/farmacología , Tripsina , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo , Serina Endopeptidasas , Inhibidores de Serina Proteinasa/química , Inhibidores de Serina Proteinasa/farmacología
7.
Molecules ; 29(11)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38893535

RESUMEN

The aim of this study was to investigate the transition from non-covalent reversible over covalent reversible to covalent irreversible inhibition of cysteine proteases by making delicate structural changes to the warhead scaffold. To this end, dipeptidic rhodesain inhibitors with different N-terminal electrophilic arenes as warheads relying on the SNAr mechanism were synthesized and investigated. Strong structure-activity relationships of the inhibition potency, the degree of covalency, and the reversibility of binding on the arene substitution pattern were found. The studies were complemented and substantiated by molecular docking and quantum-mechanical calculations of model systems. Furthermore, the improvement in the membrane permeability of peptide esters in comparison to their corresponding carboxylic acids was exemplified.


Asunto(s)
Proteasas de Cisteína , Inhibidores de Cisteína Proteinasa , Simulación del Acoplamiento Molecular , Inhibidores de Cisteína Proteinasa/química , Inhibidores de Cisteína Proteinasa/farmacología , Inhibidores de Cisteína Proteinasa/metabolismo , Relación Estructura-Actividad , Proteasas de Cisteína/metabolismo , Proteasas de Cisteína/química , Cisteína Endopeptidasas/metabolismo , Cisteína Endopeptidasas/química , Estructura Molecular
8.
PLoS Med ; 20(7): e1004259, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37471395

RESUMEN

BACKGROUND: Ethnic and socioeconomic inequalities in obstetric outcomes are well established. However, the role of induction of labour (IOL) to reduce these inequalities is controversial, in part due to insufficient evidence. This national cohort study aimed to identify adverse perinatal outcomes associated with IOL with birth at 39 weeks of gestation ("IOL group") compared to expectant management ("expectant management group") according to maternal characteristics in women with low-risk pregnancies. METHODS AND FINDINGS: All English National Health Service (NHS) hospital births between January 2018 and March 2021 were examined. Using the Hospital Episode Statistics (HES) dataset, maternal and neonatal data (demographic, diagnoses, procedures, labour, and birth details) were linked, with neonatal mortality data from the Office for National Statistics (ONS). Women with a low-risk pregnancy were identified by excluding pregnancies with preexisting comorbidities, previous cesarean section, breech presentation, placenta previa, gestational diabetes, or a baby with congenital abnormalities. Women with premature rupture of membranes, placental abruption, hypertensive disorders of pregnancy, amniotic fluid abnormalities, or antepartum stillbirth were excluded only from the IOL group. Adverse perinatal outcome was defined as stillbirth, neonatal death, or neonatal morbidity, the latter identified using the English composite neonatal outcome indicator (E-NAOI). Binomial regression models estimated risk differences (with 95% confidence intervals (CIs)) between the IOL group and the expectant management group, adjusting for ethnicity, socioeconomic background, maternal age, parity, year of birth, and birthweight centile. Interaction tests examined risk differences according to ethnicity, socioeconomic background, and parity. Of the 1 567 004 women with singleton pregnancies, 501 072 women with low-risk pregnancies and with sufficient data quality were included in the analysis. Approximately 3.3% of births in the IOL group (1 555/47 352) and 3.6% in the expectant management group (16 525/453 720) had an adverse perinatal outcome. After adjustment, a lower risk of adverse perinatal outcomes was found in the IOL group (risk difference -0.28%; 95% CI -0.43%, -0.12%; p = 0.001). This risk difference varied according to socioeconomic background from 0.38% (-0.08%, 0.83%) in the least deprived to -0.48% (-0.76%, -0.20%) in the most deprived national quintile (p-value for interaction = 0.01) and by parity with risk difference of -0.54% (-0.80%, -0.27%) in nulliparous women and -0.15% (-0.35%, 0.04%) in multiparous women (p-value for interaction = 0.02). There was no statistically significant evidence that risk differences varied according to ethnicity (p = 0.19). Key limitations included absence of additional confounding factors such as smoking, BMI, and the indication for induction in the HES datasets, which may mean some higher risk pregnancies were included. CONCLUSIONS: IOL with birth at 39 weeks was associated with a small reduction in the risk of adverse perinatal outcomes, with 360 inductions in low-risk pregnancies needed to avoid 1 adverse outcome. The risk reduction was mainly present in women from more socioeconomically deprived areas and in nulliparous women. There was no significant risk difference found by ethnicity. Increased uptake of IOL at 39 weeks, especially in women from more socioeconomically deprived areas, may help reduce inequalities in adverse perinatal outcomes.


Asunto(s)
Cesárea , Mortinato , Recién Nacido , Embarazo , Femenino , Humanos , Paridad , Estudios de Cohortes , Etnicidad , Medicina Estatal , Placenta , Trabajo de Parto Inducido/efectos adversos , Inglaterra/epidemiología , Factores Socioeconómicos
9.
Chemistry ; 29(54): e202301978, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37404217

RESUMEN

Given the prevalence of molecules containing nitro groups in organic synthesis, innovative methods to expand the reactivity of this functional group are of interest in both industrial and academic settings. In this report, a metal-free intramolecular benzylic sp3 C-H amination is disclosed using aryl nitro compounds as aryl nitrene precursors. Organosilicon reagent N,N'-bis(trimethylsilyl)-4,4'-bipyridinylidene (Si-DHBP) served as an efficient reductant in the transformation, enabling the in situ generation of aryl nitrene species for the direct, metal-free synthesis of unprotected 2-arylindolines from the corresponding nitroarene compounds.

10.
Chemistry ; 29(50): e202301855, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37313627

RESUMEN

Fluorometric assays are one of the most frequently used methods in medicinal chemistry. Over the last 50 years, the reporter molecules for the detection of protease activity have evolved from first-generation colorimetric p-nitroanilides, through FRET substrates, and 7-amino-4-methyl coumarin (AMC)-based substrates. The aim of further substrate development is to increase sensitivity and reduce vulnerability to assay interferences. Herein, we describe a new generation of substrates for protease assays based on 7-nitrobenz-2-oxa-1,3-diazol-4-yl-amides (NBD-amides). In this study, we synthesized and tested substrates for 10 different proteases from the serine-, cysteine-, and metalloprotease classes. Enzyme- and substrate-specific parameters as well as the inhibitory activity of literature-known inhibitors confirmed their suitability for application in fluorometric assays. Hence, we were able to present NBD-based alternatives for common protease substrates. In conclusion, these NBD substrates are not only less susceptible to common assay interference, but they are also able to replace FRET-based substrates with the requirement of a prime site amino acid residue.


Asunto(s)
Amidas , Péptido Hidrolasas , Colorantes Fluorescentes/metabolismo , Fluorometría , Endopeptidasas
11.
PLoS Biol ; 18(12): e3000919, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33351791

RESUMEN

Computational protein design is rapidly becoming more powerful, and improving the accuracy of computational methods would greatly streamline protein engineering by eliminating the need for empirical optimization in the laboratory. In this work, we set out to design novel granulopoietic agents using a rescaffolding strategy with the goal of achieving simpler and more stable proteins. All of the 4 experimentally tested designs were folded, monomeric, and stable, while the 2 determined structures agreed with the design models within less than 2.5 Å. Despite the lack of significant topological or sequence similarity to their natural granulopoietic counterpart, 2 designs bound to the granulocyte colony-stimulating factor (G-CSF) receptor and exhibited potent, but delayed, in vitro proliferative activity in a G-CSF-dependent cell line. Interestingly, the designs also induced proliferation and differentiation of primary human hematopoietic stem cells into mature granulocytes, highlighting the utility of our approach to develop highly active therapeutic leads purely based on computational design.


Asunto(s)
Granulocitos/citología , Ingeniería de Proteínas/métodos , Diferenciación Celular , Células Cultivadas , Biología Computacional/métodos , Factor Estimulante de Colonias de Granulocitos/farmacología , Granulocitos/efectos de los fármacos , Hematopoyesis/efectos de los fármacos , Hematopoyesis/fisiología , Células Madre Hematopoyéticas/citología , Humanos , Neutrófilos , Relación Estructura-Actividad
12.
Inorg Chem ; 62(41): 16661-16668, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37782818

RESUMEN

Phosphine-stabilized monovalent nickel complexes play an important role in catalysis, either as catalytically active species or as decomposition products. Most routes to access these complexes are highly ligand specific or rely on strong reducing agents. Our group recently disclosed a path to access nickel(I)-phenolate complexes from bis(1,5-cyclooctadiene)nickel(0) (Ni(cod)2). Herein, we demonstrate this protocol's broad applicability by ligating a wide range of mono- and bidentate phosphine ligands. We further show the versatility of the phenolate fragment as a precursor to nickel(I)-alkyl or aryl species, which are relevant to Ni catalysis or synthetically useful nickel(I)-chloride and hydride complexes. We also demonstrate that the chloride complex can be synthesized in a one-pot procedure starting from Ni(cod)2 in good yield, making this protocol a valuable alternative to current procedures. Single-crystal X-ray diffraction, IR, and EPR (or NMR) spectroscopy were employed to characterize all of the synthesized nickel complexes.

13.
Gerontology ; 69(1): 73-81, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35605581

RESUMEN

AIM: We planned a cross-sectional investigation (study 1) and a longitudinal training intervention (study 2) to investigate whether recreational dancing affords greater neuroprotective effects against age-related neuromuscular junction (NMJ) degeneration compared to general fitness exercise training. METHODS: In study 1, we recruited 19 older volunteers regularly practising dancing (older dancers [OD]) and 15 recreationally physically active older individuals (OA) and physical performance, muscle morphology, muscle function, and NMJ stability (from serum C-terminal agrin fragment [CAF] concentration) were assessed. In study 2, employing a longitudinal study design in a different cohort (composed of 37 older adults), we aimed to study whether a 6-month dancing intervention decreased CAF concentration compared to general fitness exercise training in older adults. RESULTS: Our findings show that OD had a lower CAF concentration (suggesting an increased NMJ stability) compared to OA. This result was accompanied by superior functional performance despite no differences in muscle size. In study 2, we observed a reduction in CAF concentration only in the dancing group. CONCLUSION: Overall, these findings suggest that dancing is an effective training modality to promote neuroprotection and increase muscle function in healthy older individuals.


Asunto(s)
Baile , Fármacos Neuroprotectores , Humanos , Anciano , Baile/fisiología , Estudios Longitudinales , Estudios Transversales , Envejecimiento
14.
Nucleic Acids Res ; 49(20): 11666-11689, 2021 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-34718742

RESUMEN

The inhibitor of DNA-binding 3 (ID3) is a transcriptional regulator that limits interaction of basic helix-loop-helix transcription factors with their target DNA sequences. We previously reported that ID3 loss is associated with mutational signatures linked to DNA repair defects. Here we demonstrate that ID3 exhibits a dual role to promote DNA double-strand break (DSB) repair, particularly homologous recombination (HR). ID3 interacts with the MRN complex and RECQL helicase to activate DSB repair and it facilitates RAD51 loading and downstream steps of HR. In addition, ID3 promotes the expression of HR genes in response to ionizing radiation by regulating both chromatin accessibility and activity of the transcription factor E2F1. Consistently, analyses of TCGA cancer patient data demonstrate that low ID3 expression is associated with impaired HR. The loss of ID3 leads to sensitivity of tumor cells to PARP inhibition, offering new therapeutic opportunities in ID3-deficient tumors.


Asunto(s)
Recombinación Homóloga , Proteínas Inhibidoras de la Diferenciación/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias de la Próstata/genética , Línea Celular Tumoral , Roturas del ADN de Doble Cadena , Resistencia a Antineoplásicos , Factor de Transcripción E2F1/metabolismo , Células HEK293 , Humanos , Proteínas Inhibidoras de la Diferenciación/química , Masculino , Proteínas de Neoplasias/química , Inhibidores de Poli(ADP-Ribosa) Polimerasas/toxicidad , Poli(ADP-Ribosa) Polimerasas/metabolismo , Recombinasa Rad51/metabolismo , RecQ Helicasas/metabolismo
15.
Adv Exp Med Biol ; 1412: 97-115, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37378763

RESUMEN

Approximately 30% of COVID-19 cases may experience chronic symptoms, known as post-COVID-19 syndrome (PCS). Common PCS symptoms can include fatigue, cognitive impairment, and persistent physical, neurological, and neuropsychiatric complaints. To improve healthcare and management of the current and future pandemics, we highlight the need for establishing interdisciplinary post-viral outpatient clinics comprised of specialists in fields such as psychiatry, psychotherapy, neurology, cardiology, pneumology, and immunology. In this way, PCS patients with a high health burden can receive modern diagnostics and targeted therapeutic recommendations. A key objective is to distinguish the "sick recovered" from the "healthy recovered." Our hypothesis is that there is a PCS subgroup with autoimmune-mediated systemic and brain-vascular dysregulation, which may lead to circulatory disorders, fatigue, cognitive impairment, depression, and anxiety. This can be clarified using a combination of specific antibody diagnostics and precise clinical, psychological, and apparative testing.


Asunto(s)
COVID-19 , Triaje , Humanos , Síndrome Post Agudo de COVID-19 , COVID-19/complicaciones , Biomarcadores , Fatiga
16.
Int J Mol Sci ; 24(8)2023 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-37108388

RESUMEN

Covalent peptidomimetic protease inhibitors have gained a lot of attention in drug development in recent years. They are designed to covalently bind the catalytically active amino acids through electrophilic groups called warheads. Covalent inhibition has an advantage in terms of pharmacodynamic properties but can also bear toxicity risks due to non-selective off-target protein binding. Therefore, the right combination of a reactive warhead with a well-suited peptidomimetic sequence is of great importance. Herein, the selectivities of well-known warheads combined with peptidomimetic sequences suited for five different proteases were investigated, highlighting the impact of both structure parts (warhead and peptidomimetic sequence) for affinity and selectivity. Molecular docking gave insights into the predicted binding modes of the inhibitors inside the binding pockets of the different enzymes. Moreover, the warheads were investigated by NMR and LC-MS reactivity assays against serine/threonine and cysteine nucleophile models, as well as by quantum mechanics simulations.


Asunto(s)
Peptidomiméticos , Inhibidores de Proteasas , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/química , Peptidomiméticos/farmacología , Simulación del Acoplamiento Molecular , Aminoácidos/química , Cisteína/metabolismo
17.
J Environ Manage ; 326(Pt B): 116755, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36413955

RESUMEN

This study, based on 2019 data, investigates the cost-effectiveness of Shore Side Electricity (SSE) adoption utilising the existing and future (2030) Irish energy mix, while considering different levels of adoption across six scenarios, incorporating both "port-side" and "ship-side" private costs alongside the benefits from reduced external costs and avoided Auxiliary Engine (AE) fuel costs. Passenger ships calling to the two most populated Irish port cities of Dublin and Belfast were selected as the case study, owing to the significance of such ports and ship types in the Irish maritime economy. For the existing Irish energy mix, the most optimal solution among the discussed scenarios was that of switching the top 10 most frequent passenger ship callers in Dublin and Belfast to SSE, as it reflected the highest Net Present Values (NPV) of €34.06 million and €15.44 million, respectively. The future (year 2030) SSE supply is expected to be "cleaner" due to an increase in the uptake of renewable energy sources, which will further boost the obtained NPVs by 50%. A combination of public funding (by 50%), increment in supplied electricity price by 8.62% (for Dublin) and 10.01% (for Belfast) and an annual ticket price supplement (per passenger seat) by €0.03 (for Dublin) and €0.04 (for Belfast), can create a business case for the identified optimal scenario.


Asunto(s)
Electricidad , Navíos , Análisis Costo-Beneficio
18.
J Am Chem Soc ; 144(29): 13096-13108, 2022 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-35834613

RESUMEN

Functional group metathesis is an emerging field in organic chemistry with promising synthetic applications. However, no complete mechanistic studies of these reactions have been reported to date, particularly regarding the nature of the key functional group transfer mechanism. Unraveling the mechanism of these transformations would not only allow for their further improvement but would also lead to the design of novel reactions. Herein, we describe our detailed mechanistic studies of the nickel-catalyzed functional group metathesis reaction between aryl methyl sulfides and aryl nitriles, combining experimental and computational results. These studies did not support a mechanism proceeding through reversible migratory insertion of the nitrile into a Ni-Ar bond and provided strong support for an alternative mechanism involving a key transmetalation step between two independently generated oxidative addition complexes. Extensive kinetic analysis, including rate law determination and Eyring analysis, indicated the oxidative addition complex of aryl nitrile as the resting state of the catalytic reaction. Depending on the concentration of aryl methyl sulfide, either the reductive elimination of aryl nitrile or the oxidative addition into the C(sp2)-S bond of aryl methyl sulfide is the turnover-limiting step of the reaction. NMR studies, including an unusual 31P-2H HMBC experiment using deuterium-labeled complexes, unambiguously demonstrated that the sulfide and cyanide groups exchange during the transmetalation step, rather than the two aryl moieties. In addition, Eyring and Hammett analyses of the transmetalation between two Ni(II) complexes revealed that this central step proceeds via an associative mechanism. Organometallic studies involving the synthesis, isolation, and characterization of all putative intermediates and possible deactivation complexes have further shed light on the reaction mechanism, including the identification of a key deactivation pathway, which has led to an improved catalytic protocol.


Asunto(s)
Níquel , Nitrilos , Catálisis , Cinética , Níquel/química , Sulfuros
19.
PLoS Med ; 19(1): e1003884, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35007282

RESUMEN

BACKGROUND: The COVID-19 pandemic has disrupted maternity services worldwide and imposed restrictions on societal behaviours. This national study aimed to compare obstetric intervention and pregnancy outcome rates in England during the pandemic and corresponding pre-pandemic calendar periods, and to assess whether differences in these rates varied according to ethnic and socioeconomic background. METHODS AND FINDINGS: We conducted a national study of singleton births in English National Health Service hospitals. We compared births during the COVID-19 pandemic period (23 March 2020 to 22 February 2021) with births during the corresponding calendar period 1 year earlier. The Hospital Episode Statistics database provided administrative hospital data about maternal characteristics, obstetric inventions (induction of labour, elective or emergency cesarean section, and instrumental birth), and outcomes (stillbirth, preterm birth, small for gestational age [SGA; birthweight < 10th centile], prolonged maternal length of stay (≥3 days), and maternal 42-day readmission). Multi-level logistic regression models were used to compare intervention and outcome rates between the corresponding pre-pandemic and pandemic calendar periods and to test for interactions between pandemic period and ethnic and socioeconomic background. All models were adjusted for maternal characteristics including age, obstetric history, comorbidities, and COVID-19 status at birth. The study included 948,020 singleton births (maternal characteristics: median age 30 years, 41.6% primiparous, 8.3% with gestational diabetes, 2.4% with preeclampsia, and 1.6% with pre-existing diabetes or hypertension); 451,727 births occurred during the defined pandemic period. Maternal characteristics were similar in the pre-pandemic and pandemic periods. Compared to the pre-pandemic period, stillbirth rates remained similar (0.36% pandemic versus 0.37% pre-pandemic, p = 0.16). Preterm birth and SGA birth rates were slightly lower during the pandemic (6.0% versus 6.1% for preterm births, adjusted odds ratio [aOR] 0.96, 95% CI 0.94-0.97; 5.6% versus 5.8% for SGA births, aOR 0.95, 95% CI 0.93-0.96; both p < 0.001). Slightly higher rates of obstetric intervention were observed during the pandemic (40.4% versus 39.1% for induction of labour, aOR 1.04, 95% CI 1.03-1.05; 13.9% versus 12.9% for elective cesarean section, aOR 1.13, 95% CI 1.11-1.14; 18.4% versus 17.0% for emergency cesarean section, aOR 1.07, 95% CI 1.06-1.08; all p < 0.001). Lower rates of prolonged maternal length of stay (16.7% versus 20.2%, aOR 0.77, 95% CI 0.76-0.78, p < 0.001) and maternal readmission (3.0% versus 3.3%, aOR 0.88, 95% CI 0.86-0.90, p < 0.001) were observed during the pandemic period. There was some evidence that differences in the rates of preterm birth, emergency cesarean section, and unassisted vaginal birth varied according to the mother's ethnic background but not according to her socioeconomic background. A key limitation is that multiple comparisons were made, increasing the chance of false-positive results. CONCLUSIONS: In this study, we found very small decreases in preterm birth and SGA birth rates and very small increases in induction of labour and elective and emergency cesarean section during the COVID-19 pandemic, with some evidence of a slightly different pattern of results in women from ethnic minority backgrounds. These changes in obstetric intervention rates and pregnancy outcomes may be linked to women's behaviour, environmental exposure, changes in maternity practice, or reduced staffing levels.


Asunto(s)
COVID-19/epidemiología , Parto Obstétrico/tendencias , Complicaciones del Trabajo de Parto/epidemiología , Resultado del Embarazo/epidemiología , Medicina Estatal/tendencias , Adolescente , Adulto , COVID-19/prevención & control , Estudios de Cohortes , Parto Obstétrico/estadística & datos numéricos , Inglaterra/epidemiología , Femenino , Humanos , Recién Nacido , Complicaciones del Trabajo de Parto/diagnóstico , Embarazo , Medicina Estatal/estadística & datos numéricos , Adulto Joven
20.
Lancet ; 398(10314): 1905-1912, 2021 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-34735797

RESUMEN

BACKGROUND: Socioeconomic deprivation and minority ethnic background are risk factors for adverse pregnancy outcomes. We aimed to quantify the magnitude of these socioeconomic and ethnic inequalities at the population level in England. METHODS: In this cohort study, we used data compiled by the National Maternity and Perinatal Audit, based on birth records from maternity information systems used by 132 National Health Service hospitals in England, linked to administrative hospital data. We included women who gave birth to a singleton baby with a recorded gestation between 24 and 42 completed weeks. Terminations of pregnancy were excluded. We analysed data on stillbirth, preterm birth (<37 weeks of gestation), and fetal growth restriction (FGR; liveborn with birthweight <3rd centile by the UK definition) in England, and compared these outcomes by socioeconomic deprivation quintile and ethnic group. We calculated attributable fractions for the entire population and specific groups compared with least deprived groups or White women, both unadjusted and with adjustment for smoking, body-mass index (BMI), and other maternal risk factors. FINDINGS: We identified 1 233 184 women with a singleton birth between April 1, 2015, and March 31, 2017, of whom 1 155 981 women were eligible and included in the analysis. 4505 (0·4%) of 1 155 981 births were stillbirths. Of 1 151 476 livebirths, 69 175 (6·0%) were preterm births and 22 679 (2·0%) were births with FGR. Risk of stillbirth was 0·3% in the least socioeconomically deprived group and 0·5% in the most deprived group (p<0·0001), risk of a preterm birth was 4·9% in the least deprived group and 7·2% in the most deprived group (p<0·0001), and risk of FGR was 1·2% in the least deprived group and 2·2% in the most deprived group (p<0·0001). Population attributable fractions indicated that 23·6% (95% CI 16·7-29·8) of stillbirths, 18·5% (16·9-20·2) of preterm births, and 31·1% (28·3-33·8) of births with FGR could be attributed to socioeconomic inequality, and these fractions were substantially reduced when adjusted for ethnic group, smoking, and BMI (11·6% for stillbirths, 11·9% for preterm births, and 16·4% for births with FGR). Risk of stillbirth ranged from 0·3% in White women to 0·7% in Black women (p<0·0001); risk of preterm birth was 6·0% in White women, 6·5% in South Asian women, and 6·6% in Black women (p<0·0001); and risk of FGR ranged from 1·4% in White women to 3·5% in South Asian women (p<0·0001). 11·7% of stillbirths (95% CI 9·8-13·5), 1·2% of preterm births (0·8-1·6), and 16·9% of FGR (16·1-17·8) could be attributed to ethnic inequality. Adjustment for socioeconomic deprivation, smoking, and BMI only had a small effect on these ethnic group attributable fractions (13·0% for stillbirths, 2·6% for preterm births, and 19·2% for births with FGR). Group-specific attributable fractions were especially high in the most socioeconomically deprived South Asian women and Black women for stillbirth (53·5% in South Asian women and 63·7% in Black women) and FGR (71·7% in South Asian women and 55·0% in Black women). INTERPRETATION: Our results indicate that socioeconomic and ethnic inequalities were responsible for a substantial proportion of stillbirths, preterm births, and births with FGR in England. The largest inequalities were seen in Black and South Asian women in the most socioeconomically deprived quintile. Prevention should target the entire population as well as specific minority ethnic groups at high risk of adverse pregnancy outcomes, to address risk factors and wider determinants of health. FUNDING: Healthcare Quality Improvement Partnership.


Asunto(s)
Grupos Minoritarios/estadística & datos numéricos , Resultado del Embarazo/epidemiología , Factores Socioeconómicos , Índice de Masa Corporal , Estudios de Cohortes , Inglaterra/epidemiología , Femenino , Retardo del Crecimiento Fetal/epidemiología , Humanos , Embarazo , Nacimiento Prematuro/epidemiología , Fumar , Mortinato/epidemiología
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