Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.547
Filtrar
Más filtros

Intervalo de año de publicación
1.
Cell ; 186(5): 957-974.e28, 2023 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-36812912

RESUMEN

Bats are distinctive among mammals due to their ability to fly, use laryngeal echolocation, and tolerate viruses. However, there are currently no reliable cellular models for studying bat biology or their response to viral infections. Here, we created induced pluripotent stem cells (iPSCs) from two species of bats: the wild greater horseshoe bat (Rhinolophus ferrumequinum) and the greater mouse-eared bat (Myotis myotis). The iPSCs from both bat species showed similar characteristics and had a gene expression profile resembling that of cells attacked by viruses. They also had a high number of endogenous viral sequences, particularly retroviruses. These results suggest that bats have evolved mechanisms to tolerate a large load of viral sequences and may have a more intertwined relationship with viruses than previously thought. Further study of bat iPSCs and their differentiated progeny will provide insights into bat biology, virus host relationships, and the molecular basis of bats' special traits.


Asunto(s)
Quirópteros , Células Madre Pluripotentes , Virosis , Virus , Animales , Virus/genética , Transcriptoma , Filogenia
2.
Proc Natl Acad Sci U S A ; 121(9): e2214756121, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38394243

RESUMEN

Sleep, circadian rhythms, and mental health are reciprocally interlinked. Disruption to the quality, continuity, and timing of sleep can precipitate or exacerbate psychiatric symptoms in susceptible individuals, while treatments that target sleep-circadian disturbances can alleviate psychopathology. Conversely, psychiatric symptoms can reciprocally exacerbate poor sleep and disrupt clock-controlled processes. Despite progress in elucidating underlying mechanisms, a cohesive approach that integrates the dynamic interactions between psychiatric disorder with both sleep and circadian processes is lacking. This review synthesizes recent evidence for sleep-circadian dysfunction as a transdiagnostic contributor to a range of psychiatric disorders, with an emphasis on biological mechanisms. We highlight observations from adolescent and young adults, who are at greatest risk of developing mental disorders, and for whom early detection and intervention promise the greatest benefit. In particular, we aim to a) integrate sleep and circadian factors implicated in the pathophysiology and treatment of mood, anxiety, and psychosis spectrum disorders, with a transdiagnostic perspective; b) highlight the need to reframe existing knowledge and adopt an integrated approach which recognizes the interaction between sleep and circadian factors; and c) identify important gaps and opportunities for further research.


Asunto(s)
Trastornos Mentales , Trastornos del Sueño-Vigilia , Adulto Joven , Adolescente , Humanos , Trastornos Mentales/etiología , Trastornos Mentales/terapia , Sueño/fisiología , Ritmo Circadiano/fisiología , Salud Mental , Trastornos del Humor
3.
Nature ; 580(7801): 87-92, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32238927

RESUMEN

Southern Ocean ecosystems are under pressure from resource exploitation and climate change1,2. Mitigation requires the identification and protection of Areas of Ecological Significance (AESs), which have so far not been determined at the ocean-basin scale. Here, using assemblage-level tracking of marine predators, we identify AESs for this globally important region and assess current threats and protection levels. Integration of more than 4,000 tracks from 17 bird and mammal species reveals AESs around sub-Antarctic islands in the Atlantic and Indian Oceans and over the Antarctic continental shelf. Fishing pressure is disproportionately concentrated inside AESs, and climate change over the next century is predicted to impose pressure on these areas, particularly around the Antarctic continent. At present, 7.1% of the ocean south of 40°S is under formal protection, including 29% of the total AESs. The establishment and regular revision of networks of protection that encompass AESs are needed to provide long-term mitigation of growing pressures on Southern Ocean ecosystems.


Asunto(s)
Sistemas de Identificación Animal , Organismos Acuáticos/fisiología , Cambio Climático/estadística & datos numéricos , Conservación de los Recursos Naturales/métodos , Ecosistema , Océanos y Mares , Conducta Predatoria , Animales , Regiones Antárticas , Biodiversidad , Aves , Peces , Cadena Alimentaria , Cubierta de Hielo , Mamíferos , Dinámica Poblacional
4.
Nucleic Acids Res ; 52(D1): D1438-D1449, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37897341

RESUMEN

The IUPHAR/BPS Guide to PHARMACOLOGY (GtoPdb; https://www.guidetopharmacology.org) is an open-access, expert-curated, online database that provides succinct overviews and key references for pharmacological targets and their recommended experimental ligands. It includes over 3039 protein targets and 12 163 ligand molecules, including approved drugs, small molecules, peptides and antibodies. Here, we report recent developments to the resource and describe expansion in content over the six database releases made during the last two years. The database update section of this paper focuses on two areas relating to important global health challenges. The first, SARS-CoV-2 COVID-19, remains a major concern and we describe our efforts to expand the database to include a new family of coronavirus proteins. The second area is antimicrobial resistance, for which we have extended our coverage of antibacterials in partnership with AntibioticDB, a collaboration that has continued through support from GARDP. We discuss other areas of curation and also focus on our external links to resources such as PubChem that bring important synergies to the resources.


Asunto(s)
Bases de Datos Farmacéuticas , Descubrimiento de Drogas , Proteínas , Ligandos
5.
Proc Natl Acad Sci U S A ; 120(10): e2214035120, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36848574

RESUMEN

Assessing environmental changes in Southern Ocean ecosystems is difficult due to its remoteness and data sparsity. Monitoring marine predators that respond rapidly to environmental variation may enable us to track anthropogenic effects on ecosystems. Yet, many long-term datasets of marine predators are incomplete because they are spatially constrained and/or track ecosystems already modified by industrial fishing and whaling in the latter half of the 20th century. Here, we assess the contemporary offshore distribution of a wide-ranging marine predator, the southern right whale (SRW, Eubalaena australis), that forages on copepods and krill from ~30°S to the Antarctic ice edge (>60°S). We analyzed carbon and nitrogen isotope values of 1,002 skin samples from six genetically distinct SRW populations using a customized assignment approach that accounts for temporal and spatial variation in the Southern Ocean phytoplankton isoscape. Over the past three decades, SRWs increased their use of mid-latitude foraging grounds in the south Atlantic and southwest (SW) Indian oceans in the late austral summer and autumn and slightly increased their use of high-latitude (>60°S) foraging grounds in the SW Pacific, coincident with observed changes in prey distribution and abundance on a circumpolar scale. Comparing foraging assignments with whaling records since the 18th century showed remarkable stability in use of mid-latitude foraging areas. We attribute this consistency across four centuries to the physical stability of ocean fronts and resulting productivity in mid-latitude ecosystems of the Southern Ocean compared with polar regions that may be more influenced by recent climate change.


Asunto(s)
Cambio Climático , Ecosistema , Animales , Regiones Antárticas , Efectos Antropogénicos , Océano Índico
6.
Lancet ; 404(10448): 134-144, 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-38908392

RESUMEN

BACKGROUND: Recurrence of low back pain is common and a substantial contributor to the disease and economic burden of low back pain. Exercise is recommended to prevent recurrence, but the effectiveness and cost-effectiveness of an accessible and low-cost intervention, such as walking, is yet to be established. We aimed to investigate the clinical effectiveness and cost-effectiveness of an individualised, progressive walking and education intervention to prevent the recurrence of low back pain. METHODS: WalkBack was a two-armed, randomised controlled trial, which recruited adults (aged 18 years or older) from across Australia who had recently recovered from an episode of non-specific low back pain that was not attributed to a specific diagnosis, and which lasted for at least 24 h. Participants were randomly assigned to an individualised, progressive walking and education intervention facilitated by six sessions with a physiotherapist across 6 months or to a no treatment control group (1:1). The randomisation schedule comprised randomly permuted blocks of 4, 6, and 8 and was stratified by history of more than two previous episodes of low back pain and referral method. Physiotherapists and participants were not masked to allocation. Participants were followed for a minimum of 12 months and a maximum of 36 months, depending on the date of enrolment. The primary outcome was days to the first recurrence of an activity-limiting episode of low back pain, collected in the intention-to-treat population via monthly self-report. Cost-effectiveness was evaluated from the societal perspective and expressed as incremental cost per quality-adjusted life-year (QALY) gained. The trial was prospectively registered (ACTRN12619001134112). FINDINGS: Between Sept 23, 2019, and June 10, 2022, 3206 potential participants were screened for eligibility, 2505 (78%) were excluded, and 701 were randomly assigned (351 to the intervention group and 350 to the no treatment control group). Most participants were female (565 [81%] of 701) and the mean age of participants was 54 years (SD 12). The intervention was effective in preventing an episode of activity-limiting low back pain (hazard ratio 0·72 [95% CI 0·60-0·85], p=0·0002). The median days to a recurrence was 208 days (95% CI 149-295) in the intervention group and 112 days (89-140) in the control group. The incremental cost per QALY gained was AU$7802, giving a 94% probability that the intervention was cost-effective at a willingness-to-pay threshold of $28 000. Although the total number of participants experiencing at least one adverse event over 12 months was similar between the intervention and control groups (183 [52%] of 351 and 190 [54%] of 350, respectively, p=0·60), there was a greater number of adverse events related to the lower extremities in the intervention group than in the control group (100 in the intervention group and 54 in the control group). INTERPRETATION: An individualised, progressive walking and education intervention significantly reduced low back pain recurrence. This accessible, scalable, and safe intervention could affect how low back pain is managed. FUNDING: National Health and Medical Research Council, Australia.


Asunto(s)
Análisis Costo-Beneficio , Dolor de la Región Lumbar , Prevención Secundaria , Caminata , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Australia , Terapia por Ejercicio/economía , Terapia por Ejercicio/métodos , Dolor de la Región Lumbar/prevención & control , Dolor de la Región Lumbar/economía , Educación del Paciente como Asunto/métodos , Educación del Paciente como Asunto/economía , Años de Vida Ajustados por Calidad de Vida , Prevención Secundaria/economía , Prevención Secundaria/métodos , Resultado del Tratamiento , Anciano
7.
J Infect Dis ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916431

RESUMEN

BACKGROUND: Post-COVID conditions (PCC) are difficult to characterize, diagnose, predict, and treat due to overlapping symptoms and poorly understood pathology. Identifying inflammatory profiles may improve clinical prognostication and trial endpoints. METHODS: 1,988 SARS-CoV-2 positive U.S. Military Health System beneficiaries with quantitative post-COVID symptom scores were included in this analysis. Among participants who reported moderate-to-severe symptoms on surveys collected 6-months post-SARS-CoV-2 infection, principal component analysis (PCA) followed by K-means clustering identified distinct clusters of symptoms. RESULTS: Three symptom-based clusters were identified: a sensory cluster (loss of smell and/or taste), a fatigue/difficulty thinking cluster, and a difficulty breathing/exercise intolerance cluster. Individuals within the sensory cluster were all outpatients during their initial COVID-19 presentation. The difficulty breathing cluster had a higher likelihood of obesity and COVID-19 hospitalization compared to those with no/mild symptoms at 6-months post-infection. Multinomial regression linked early post-infection D-dimer and IL-1RA elevation to fatigue/difficulty thinking, and elevated ICAM-1 concentrations to sensory symptoms. CONCLUSIONS: We identified three distinct symptom-based PCC phenotypes with specific clinical risk factors and early post-infection inflammatory predictors. With further validation and characterization, this framework may allow more precise classification of PCC cases and potentially improve the diagnosis, prognostication, and treatment of PCC.

8.
Gut ; 73(7): 1052-1075, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38609165

RESUMEN

The first British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS)-endorsed faecal microbiota transplant (FMT) guidelines were published in 2018. Over the past 5 years, there has been considerable growth in the evidence base (including publication of outcomes from large national FMT registries), necessitating an updated critical review of the literature and a second edition of the BSG/HIS FMT guidelines. These have been produced in accordance with National Institute for Health and Care Excellence-accredited methodology, thus have particular relevance for UK-based clinicians, but are intended to be of pertinence internationally. This second edition of the guidelines have been divided into recommendations, good practice points and recommendations against certain practices. With respect to FMT for Clostridioides difficile infection (CDI), key focus areas centred around timing of administration, increasing clinical experience of encapsulated FMT preparations and optimising donor screening. The latter topic is of particular relevance given the COVID-19 pandemic, and cases of patient morbidity and mortality resulting from FMT-related pathogen transmission. The guidelines also considered emergent literature on the use of FMT in non-CDI settings (including both gastrointestinal and non-gastrointestinal indications), reviewing relevant randomised controlled trials. Recommendations are provided regarding special areas (including compassionate FMT use), and considerations regarding the evolving landscape of FMT and microbiome therapeutics.


Asunto(s)
Infecciones por Clostridium , Trasplante de Microbiota Fecal , Gastroenterología , Trasplante de Microbiota Fecal/métodos , Humanos , Infecciones por Clostridium/terapia , Gastroenterología/normas , COVID-19/terapia , SARS-CoV-2 , Recurrencia , Clostridioides difficile , Reino Unido , Sociedades Médicas
9.
J Am Chem Soc ; 146(18): 12836-12849, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38683943

RESUMEN

The biological properties of two water-soluble organic cations based on polypyridyl structures commonly used as ligands for photoactive transition metal complexes designed to interact with biomolecules are investigated. A cytotoxicity screen employing a small panel of cell lines reveals that both cations show cytotoxicity toward cancer cells but show reduced cytotoxicity to noncancerous HEK293 cells with the more extended system being notably more active. Although it is not a singlet oxygen sensitizer, the more active cation also displayed enhanced potency on irradiation with visible light, making it active at nanomolar concentrations. Using the intrinsic luminescence of the cations, their cellular uptake was investigated in more detail, revealing that the active compound is more readily internalized than its less lipophilic analogue. Colocalization studies with established cell probes reveal that the active cation predominantly localizes within lysosomes and that irradiation leads to the disruption of mitochondrial structure and function. Stimulated emission depletion (STED) nanoscopy and transmission electron microscopy (TEM) imaging reveal that treatment results in distinct lysosomal swelling and extensive cellular vacuolization. Further imaging-based studies confirm that treatment with the active cation induces lysosomal membrane permeabilization, which triggers lysosome-dependent cell-death due to both necrosis and caspase-dependent apoptosis. A preliminary toxicity screen in the Galleria melonella animal model was carried out on both cations and revealed no detectable toxicity up to concentrations of 80 mg/kg. Taken together, these studies indicate that this class of synthetically easy-to-access photoactive compounds offers potential as novel therapeutic leads.


Asunto(s)
Antineoplásicos , Cationes , Fenazinas , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Cationes/química , Cationes/farmacología , Fenazinas/química , Fenazinas/farmacología , Lisosomas/metabolismo , Lisosomas/efectos de los fármacos , Células HEK293 , Apoptosis/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Línea Celular Tumoral , Animales , Nanomedicina Teranóstica , Estructura Molecular
10.
Artículo en Inglés | MEDLINE | ID: mdl-38915286

RESUMEN

Extracellular matrix (ECM) remodeling has been implicated in the irreversible obstruction of airways and destruction of alveolar tissue in chronic obstructive pulmonary disease (COPD). Studies investigating differences in the lung ECM in COPD have mainly focused on some collagens and elastin, leaving an array of ECM components unexplored. We investigated the differences in the ECM landscape comparing severe-early onset (SEO-) COPD and moderate COPD to control lung tissue for collagen type I α chain 1 (COL1A1), COL6A1, COL6A2, COL14A1, fibulin 2 and 5 (FBLN2, FBLN5), latent transforming growth factor-beta binding protein 4 (LTBP4), lumican (LUM), versican (VCAN), decorin (DCN), and elastin (ELN) using image analysis and statistical modelling. Percentage area and/or mean intensity of expression of LUM in the parenchyma, and COL1A1, FBLN2, LTBP4, DCN, and VCAN in the airway walls, was proportionally lower in COPD compared to controls. Lowered levels of most ECM proteins were associated with decreasing FEV1 measurements, indicating a relationship with disease severity. Furthermore, we identified six unique ECM signatures where LUM and COL6A1 in parenchyma and COL1A1, FBLN5, DCN, and VCAN in airway walls appear essential in reflecting the presence and severity of COPD. These signatures emphasize the need to examine groups of proteins to represent an overall difference in the ECM landscape in COPD, that are more likely to be related to functional effects, than individual proteins. Our study revealed differences in the lung ECM landscape between control and COPD and between SEO and moderate COPD signifying distinct pathological processes in the different subgroups.

11.
J Neurochem ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898705

RESUMEN

3,4-Methylenedioxymethamphetamine (MDMA, 'ecstasy') is re-emerging in clinical settings as a candidate for the treatment of specific neuropsychiatric disorders (e.g. post-traumatic stress disorder) in combination with psychotherapy. MDMA is a psychoactive drug, typically regarded as an empathogen or entactogen, which leads to transporter-mediated monoamine release. Despite its therapeutic potential, MDMA can induce dose-, individual-, and context-dependent untoward effects outside safe settings. In this study, we investigated whether three new methylenedioxy bioisosteres of MDMA improve its off-target profile. In vitro methods included radiotracer assays, transporter electrophysiology, bioluminescence resonance energy transfer and fluorescence-based assays, pooled human liver microsome/S9 fraction incubations, metabolic stability studies, isozyme mapping, and liquid chromatography coupled to high-resolution mass spectrometry. In silico methods included molecular docking. Compared with MDMA, all three MDMA bioisosteres (ODMA, TDMA, and SeDMA) showed similar pharmacological activity at human serotonin, dopamine, and norepinephrine transporters (hSERT, hDAT, and hNET, respectively) but decreased agonist activity at 5-HT2A/2B/2C receptors. Regarding their hepatic metabolism, they differed from MDMA, with N-demethylation being the only metabolic route shared, and without forming phase II metabolites. In addition, TDMA showed an enhanced intrinsic clearance in comparison to its congeners. Additional screening for their interaction with human organic cation transporters (hOCTs) and plasma membrane monoamine transporter (hPMAT) revealed a weaker interaction of the MDMA analogs with hOCT1, hOCT2, and hPMAT. Our findings suggest that these new MDMA bioisosteres might constitute appealing therapeutic alternatives to MDMA, sparing the primary pharmacological activity at hSERT, hDAT, and hNET, but displaying a reduced activity at 5-HT2A/2B/2C receptors and alternative hepatic metabolism. Whether these MDMA bioisosteres may pose lower risk alternatives to the clinically re-emerging MDMA warrants further studies.

12.
Hum Mol Genet ; 31(24): 4217-4227, 2022 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-35899771

RESUMEN

Ets1 deletion in some mouse strains causes septal defects and has been implicated in human congenital heart defects in Jacobsen syndrome, in which one copy of the Ets1 gene is missing. Here, we demonstrate that loss of Ets1 in mice results in a decrease in neural crest (NC) cells migrating into the proximal outflow tract cushions during early heart development, with subsequent malalignment of the cushions relative to the muscular ventricular septum, resembling double outlet right ventricle (DORV) defects in humans. Consistent with this, we find that cultured cardiac NC cells from Ets1 mutant mice or derived from iPS cells from Jacobsen patients exhibit decreased migration speed and impaired cell-to-cell interactions. Together, our studies demonstrate a critical role for ETS1 for cell migration in cardiac NC cells that are required for proper formation of the proximal outflow tracts. These data provide further insights into the molecular and cellular basis for development of the outflow tracts, and how perturbation of NC cells can lead to DORV.


Asunto(s)
Cardiopatías Congénitas , Cresta Neural , Proteína Proto-Oncogénica c-ets-1 , Animales , Humanos , Ratones , Movimiento Celular/genética , Corazón , Organogénesis , Proteína Proto-Oncogénica c-ets-1/genética
13.
Lancet ; 402(10406): 975-987, 2023 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-37573859

RESUMEN

BACKGROUND: Insomnia is prevalent and distressing but access to the first-line treatment, cognitive behavioural therapy (CBT), is extremely limited. We aimed to assess the clinical and cost-effectiveness of sleep restriction therapy, a key component of CBT, which has the potential to be widely implemented. METHODS: We did a pragmatic, superiority, open-label, randomised controlled trial of sleep restriction therapy versus sleep hygiene. Adults with insomnia disorder were recruited from 35 general practices across England and randomly assigned (1:1) using a web-based randomisation programme to either four sessions of nurse-delivered sleep restriction therapy plus a sleep hygiene booklet or a sleep hygiene booklet only. There was no restriction on usual care for either group. Outcomes were assessed at 3 months, 6 months, and 12 months. The primary endpoint was self-reported insomnia severity at 6 months measured with the insomnia severity index (ISI). The primary analysis included participants according to their allocated group and who contributed at least one outcome measurement. Cost-effectiveness was evaluated from the UK National Health Service and personal social services perspective and expressed in terms of incremental cost per quality-adjusted life year (QALY) gained. The trial was prospectively registered (ISRCTN42499563). FINDINGS: Between Aug 29, 2018, and March 23, 2020 we randomly assigned 642 participants to sleep restriction therapy (n=321) or sleep hygiene (n=321). Mean age was 55·4 years (range 19-88), with 489 (76·2%) participants being female and 153 (23·8%) being male. 580 (90·3%) participants provided data for at least one outcome measurement. At 6 months, mean ISI score was 10·9 (SD 5·5) for sleep restriction therapy and 13·9 (5·2) for sleep hygiene (adjusted mean difference -3·05, 95% CI -3·83 to -2·28; p<0·0001; Cohen's d -0·74), indicating that participants in the sleep restriction therapy group reported lower insomnia severity than the sleep hygiene group. The incremental cost per QALY gained was £2076, giving a 95·3% probability that treatment was cost-effective at a cost-effectiveness threshold of £20 000. Eight participants in each group had serious adverse events, none of which were judged to be related to intervention. INTERPRETATION: Brief nurse-delivered sleep restriction therapy in primary care reduces insomnia symptoms, is likely to be cost-effective, and has the potential to be widely implemented as a first-line treatment for insomnia disorder. FUNDING: The National Institute for Health and Care Research Health Technology Assessment Programme.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Adulto , Humanos , Masculino , Femenino , Adulto Joven , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Análisis Costo-Beneficio , Trastornos del Inicio y del Mantenimiento del Sueño/terapia , Resultado del Tratamiento , Medicina Estatal , Hábitos , Atención Primaria de Salud , Sueño , Calidad de Vida
14.
Small ; 20(12): e2304881, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37946631

RESUMEN

InP/ZnS quantum dots (QDs) have received a large focus in recent years as a safer alternative to heavy metal-based QDs. Given their intrinsic fluorescent imaging capabilities, these QDs can be potentially relevant for in vivo platelet imaging. The InP/ZnS QDs are synthesized and their biocompatibility investigated through the use of different phase transfer agents. Analysis of platelet function indicates that platelet-QD interaction can occur at all concentrations and for all QD permutations tested. However, as the QD concentration increases, platelet aggregation is induced by QDs alone independent of natural platelet agonists. This study helps to define a range of concentrations and coatings (thioglycolic acid and penicillamine) that are biocompatible with platelet function. With this information, the platelet-QD interaction can be identified using multiple methods. Fluorescent lifetime imaging microscopy (FLIM) and confocal studies have shown QDs localize on the surface of the platelet toward the center while showing evidence of energy transfer within the QD population. It is believed that these findings are an important stepping point for the development of fluorescent probes for platelet imaging.


Asunto(s)
Puntos Cuánticos , Ligandos
15.
Chembiochem ; 25(1): e202300625, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-37830893

RESUMEN

As the world moves towards net-zero carbon emissions, the development of sustainable chemical manufacturing processes is essential. Within manufacturing, purification by distillation is often used, however this process is energy intensive and methods that could obviate or reduce its use are desirable. Developed herein is an alternative, oxidative biocatalytic approach that enables purification of alkyl monoglucosides (essential bio-based surfactant components). Implementing an immobilised engineered alcohol oxidase, a long-chain alcohol by-product derived from alkyl monoglucoside synthesis (normally removed by distillation) is selectively oxidised to an aldehyde, conjugated to an amine resin and then removed by simple filtration. This affords recovery of the purified alkyl monoglucoside. The approach lays a blueprint for further development of sustainable alkylglycoside purification using biocatalysis and, importantly, for refining other important chemical feedstocks that currently rely on distillation.


Asunto(s)
Alcoholes , Aldehídos , Oxidación-Reducción , Biocatálisis
16.
J Anat ; 244(6): 1040-1053, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38284175

RESUMEN

That the highly trabeculated ventricular walls of the developing embryos transform to the arrangement during the fetal stages, when the mural architecture is dominated by the thickness of the compact myocardium, has been explained by the coalescence of trabeculations, often erroneously described as 'compaction'. Recent data, however, support differential rates of growth of the trabecular and compact layers as the major driver of change. Here, these processes were assessed quantitatively and visualized in standardized views. We used a larger dataset than has previously been available of mouse hearts, covering the period from embryonic day 10.5 to postnatal day 3, supported by images from human hearts. The volume of the trabecular layer increased throughout development, in contrast to what would be expected had there been 'compaction'. During the transition from embryonic to fetal life, the rapid growth of the compact layer diminished the proportion of trabeculations. Similarly, great expansion of the central cavity reduced the proportion of the total cavity made up of intertrabecular recesses. Illustrations of the hearts with the median value of left ventricular trabeculation confirm a pronounced growth of the compact wall, with prominence of the central cavity. This corresponds, in morphological terms, to a reduction in the extent of the trabecular layer. Similar observations were made in the human hearts. We conclude that it is a period of comparatively slow growth of the trabecular layer, rather than so-called compaction, that is the major determinant of the changing morphology of the ventricular walls of both mouse and human hearts.


Asunto(s)
Ventrículos Cardíacos , Animales , Humanos , Ratones , Ventrículos Cardíacos/anatomía & histología , Ventrículos Cardíacos/embriología , Edad Gestacional
17.
J Anat ; 244(3): 497-513, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37957890

RESUMEN

The separation of the outflow tract of the developing heart into the systemic and pulmonary arterial channels remains controversial and poorly understood. The definitive outflow tracts have three components. The developing outflow tract, in contrast, has usually been described in two parts. When the tract has exclusively myocardial walls, such bipartite description is justified, with an obvious dogleg bend separating proximal and distal components. With the addition of non-myocardial walls distally, it becomes possible to recognise three parts. The middle part, which initially still has myocardial walls, contains within its lumen a pair of intercalated valvar swellings. The swellings interdigitate with the distal ends of major outflow cushions, formed by the remodelling of cardiac jelly, to form the primordiums of the arterial roots. The proximal parts of the major cushions, occupying the proximal part of the outflow tract, which also has myocardial walls, themselves fuse and muscularise. The myocardial shelf thus formed remodels to become the free-standing subpulmonary infundibulum. Details of all these processes are currently lacking. In this account, we describe the anatomical changes seen during the overall remodelling. Our interpretations are based on the interrogation of serially sectioned histological and high-resolution episcopic microscopy datasets prepared from developing human and mouse embryos, with some of the datasets processed and reconstructed to reveal the specific nature of the tissues contributing to the separation of the outflow channels. Our findings confirm that the tripartite postnatal arrangement can be correlated with the changes occurring during development.


Asunto(s)
Estructuras Embrionarias , Matriz Extracelular , Cardiopatías Congénitas , Corazón , Ratones , Animales , Humanos , Ventrículos Cardíacos , Arteria Pulmonar
18.
Chemistry ; 30(3): e202303251, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-37874966

RESUMEN

Alkali nitridophosphates AP4 N7 and A3 P6 N11 (A=Na, K, Rb, Cs) have been known for decades. However, their Li homologues have remained elusive. In this work, the highly condensed lithium (imido)nitridophosphates LiP4 N7 and Li3-x P6 N11-x (NH)x (x=1.66(3)) were synthesized from LiPN2 and P3 N5 in the multianvil press at 10 GPa. They constitute the first lithium nitridophosphates with 3D networks exhibiting a degree of condensation larger than 0.5 and high thermal stability. LiP4 N7 crystallizes in the orthorhombic space group P21 21 21 with a=4.5846(6) Å, b=8.0094(11) Å, and c=13.252(2) Š(Z=4). Li3-x P6 N11-x (NH)x crystallizes in the triclinic space group P 1 - ${\mathrel{\mathop{{\rm { 1}}}\limits^{{\rm -}}}}$ with Z=2, a=4.6911(11) Å, b=7.024(2) Å, c=12.736(3) Å, α=87.726(11), ß=80.279(11), and γ=70.551(12)°. Both compounds are stable against hydrolysis in air.

19.
Chemistry ; 30(7): e202303489, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37942708

RESUMEN

We present a comprehensive account on our efforts behind the recently published synthesis of waixenicin A. Our approach for constructing the dihydropyran ring relied on an Achmatowicz rearrangement. For the assembly of the nine-membered ring, four distinct strategies were investigated. Our initial attempts using radical-based addition/fragmentation reactions targeting the C7-C11 bond proved unsuitable for accessing the 6/9-bicycle. By employing anionic fragmentation conditions at the furfuryl alcohol stage, we successfully reached a 5/9-bicycle. However, subsequent ring-expansion was unsuccessful. Alternative approaches, such as Nozaki-Hiyama-Kishi or Heck reactions to connect the C6-C7 bond, also encountered difficulties, with no nine-membered ring formation observed. Our first breakthrough came from our attempts to install the C5-C6 bond via an intramolecular alkylation. Surprisingly, subsequent functional group modifications proved unexpectedly challenging, necessitating a redesign of our synthetic route. Drawing from all our investigations, we concluded that construction of the C9-C10 bond would enable efficient nine-membered ring alkylation and would facilitate the installation of the desired substitution pattern along the southern periphery. Exploration of this strategy yielded further surprises but ultimately led to the successful synthesis of waixenicin A and 9-deacetoxy-14,15-deepoxyxeniculin. For the latter compound, a bioinspired one-step rearrangement to xeniafauranol A was achieved.

20.
J Sleep Res ; : e14143, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38384163

RESUMEN

The accuracy of actigraphy for sleep staging is assumed to be poor, but examination is limited. This systematic review aimed to assess the performance of actigraphy in sleep stage classification of adults. A systematic search was performed using MEDLINE, Web of Science, Google Scholar, and Embase databases. We identified eight studies that compared sleep architecture estimates between wrist-worn actigraphy and polysomnography. Large heterogeneity was found with respect to how sleep stages were grouped, and the choice of metrics used to evaluate performance. Quantitative synthesis was not possible, so we performed a narrative synthesis of the literature. From the limited number of studies, we found that actigraphy-based sleep staging had some ability to classify different sleep stages compared with polysomnography.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA