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1.
Biosci Rep ; 44(6)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38808772

RESUMEN

Liver fibrosis is the excessive accumulation of extracellular matrix proteins that occurs in most types of chronic liver disease. At the cellular level, liver fibrosis is associated with the activation of hepatic stellate cells (HSCs) which transdifferentiate into a myofibroblast-like phenotype that is contractile, proliferative and profibrogenic. HSC transdifferentiation induces genome-wide changes in gene expression that enable the cell to adopt its profibrogenic functions. We have previously identified that the deubiquitinase ubiquitin C-terminal hydrolase 1 (UCHL1) is highly induced following HSC activation; however, the cellular targets of its deubiquitinating activity are poorly defined. Here, we describe a role for UCHL1 in regulating the levels and activity of hypoxia-inducible factor 1 (HIF1), an oxygen-sensitive transcription factor, during HSC activation and liver fibrosis. HIF1 is elevated during HSC activation and promotes the expression of profibrotic mediator HIF target genes. Increased HIF1α expression correlated with induction of UCHL1 mRNA and protein with HSC activation. Genetic deletion or chemical inhibition of UCHL1 impaired HIF activity through reduction of HIF1α levels. Furthermore, our mechanistic studies have shown that UCHL1 elevates HIF activity through specific cleavage of degradative ubiquitin chains, elevates levels of pro-fibrotic gene expression and increases proliferation rates. As we also show that UCHL1 inhibition blunts fibrogenesis in a pre-clinical 3D human liver slice model of fibrosis, these results demonstrate how small molecule inhibitors of DUBs can exert therapeutic effects through modulation of HIF transcription factors in liver disease. Furthermore, inhibition of HIF activity using UCHL1 inhibitors may represent a therapeutic opportunity with other HIF-related pathologies.


Asunto(s)
Células Estrelladas Hepáticas , Subunidad alfa del Factor 1 Inducible por Hipoxia , Cirrosis Hepática , Ubiquitina Tiolesterasa , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/patología , Cirrosis Hepática/metabolismo , Animales , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Ratones , Humanos , Regulación de la Expresión Génica , Transdiferenciación Celular/genética
2.
Health Expect ; 27(3): e14053, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38698629

RESUMEN

INTRODUCTION: This exploratory literature review seeks to examine the literature around commissioning processes in the co-production of health and care services, focusing on two questions: How do health and care commissioning processes facilitate and/or pose barriers to co-production in service design and delivery? What are the contextual factors that influence these processes? METHOD: A systematic search of three databases (Medline, Public Health and Social Policy and Practice) and a search platform (Web of Science) was conducted for the period 2008-2023. A total of 2675 records were retrieved. After deduplication, 1925 were screened at title and abstract level. Forty-seven reports from 42 United Kingdom and Ireland studies were included in the review. A thematic synthesis of included studies was conducted in relation to the research questions. RESULTS: The review identified one overarching theme across the synthesised literature: the complexity of the commissioning landscape. Three interconnected subthemes illuminate the contextual factors that influence this landscape: commissioners as leaders of co-production; navigating relationships and the collective voice. CONCLUSION: Commissioning processes were commonly a barrier to the co-production of health and care services. Though co-production was an aspiration for many commissioners, the political and economic environment and service pressures meant that it was often not fully realised. More flexible funding models, longer-term pilot projects, an increased emphasis in social value across the health and care system and building capacity for strong leadership in commissioning is needed. PATIENT AND PUBLIC CONTRIBUTION: Patients and the public did not contribute to this review as it was a small piece of work following on from a completed project, with no budget for public involvement.


Asunto(s)
Atención a la Salud , Reino Unido , Irlanda , Humanos , Atención a la Salud/organización & administración , Medicina Estatal/organización & administración , Política de Salud
3.
Int J Hyg Environ Health ; 259: 114376, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38569415

RESUMEN

While substantial progress has been made in improving water and sanitation services in low- and middle-income countries, aligned basic services such as greywater, stormwater, and solid waste management have progressed little in recent decades. Data was collected in Khulna city, Bangladesh via a household survey (n = 192) of low-income areas exploring domestic water use and greywater volumes, characteristics, and disposal practices. Most households (71%) use a piped water supply for domestic purposes, supplemented by seasonal rainwater harvesting (26%) and greywater use (13%). Of the total water used by households (mean: 594 L/household/day and equivalent to 116 L/person/day), approximately 58% becomes greywater through bathing, dishwashing, religious practices, handwashing, laundry, and mopping. Greywater produced ranges from 61-1274 L/household/day, with a mean of 345 L/household/day and equivalent to 78.4 L/person/day. Greywater characteristics vary depending on the activity, individual behaviours and any products used during cooking, bathing, or cleaning. After generation, households dispose greywater to open drains (67%), nearby waterbodies (17%) directly to the ground (9%), or decentralised wastewater treatment system (7%). Without services for greywater management, greywater disposal may have considerable public and environmental health implications, necessitating careful attention and oversight from service-providers and stakeholders beyond the household-level.


Asunto(s)
Conservación de los Recursos Hídricos , Composición Familiar , Aguas Residuales , Abastecimiento de Agua , Humanos , Bangladesh , Ciudades , Conservación de los Recursos Hídricos/métodos
4.
Nurse Educ Pract ; 71: 103699, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37441918

RESUMEN

AIM: This scoping review aims to explore the effect of FSS and mental simulation on the decision-making skills of nursing students. BACKGROUND: Full-scale simulation (FSS) has been the most used simulation modality in nursing education due to its applicability to enhance both technical and non-technical skills. However, FSS can be excessively costly and other factors such as technophobia and lack of trained staff and support make FSS less accessible, especially for nursing education. Therefore, a novel mental simulation that is interactive and supported by visual elements can be a substitute for FSS, at least for some of the skills, such as clinical decision-making. Reviews comparing the effectiveness of FSS and mental simulation on decision-making skills in nursing students are lacking. Further knowledge on the effectiveness of these two modalities on decision-making skills for nursing students is needed to inform the nursing education curriculum and to decide between the two modalities. DESIGN: This protocol adheres to the guidelines outlined in the PRISMA extension for scoping reviews (PRISMA-scr) checklist. METHOD: The methodological framework for scoping reviews will be followed for this scoping review. Scopus, EBSCOhost the Cumulative Index to Nursing and Allied Health Literature (CINAHL), MEDLINE and for the grey literature ERIC and BASE will be searched for related studies. The search will be limited to January 2008 and April 2023 (up-to-date) and English. A detailed search strategy was developed with an experienced research information manager and this strategy will be adapted to each database. A single screening will be performed by an author who will screen all abstracts and titles and full-text publications. After the study selection step of the framework, the data from the included studies will be charted using a data extraction form. The data will be synthesised by comparing the effect of FSS and mental simulation on decision-making skills. CONCLUSION: A synopsis of the publication on FSS and mental simulation on nurse students' decision-making skills will be useful for stakeholders when choosing between two modalities to deliver decision-making skills to nursing students and also help to inform the nursing education and simulation practice. SCOPING REVIEW REGISTRATION: Protocols.io (doi: 10.17504/protocols.io.e6nvw57y7vmk/v1).


Asunto(s)
Bachillerato en Enfermería , Educación en Enfermería , Estudiantes de Enfermería , Humanos , Educación en Enfermería/métodos , Curriculum , Atención a la Salud , Revisiones Sistemáticas como Asunto
5.
Dermatol Pract Concept ; 13(2)2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37196289

RESUMEN

INTRODUCTION: Seborrheic keratosis (SK), lichen planus-like keratosis (LPLK), and solar lentigo (SL) are common benign skin lesions. These lesions are frequently seen adjacent to each other or can arise from one another. They can sometimes be difficult to differentiate despite having distinct histopathological features. OBJECTIVES: We evaluated dermoscopic images of 80 skin lesions to confirm the term 'benign keratosis' is useful for an undifferentiated SK/LPLK/SL where there are overlapping clinical and dermoscopic characteristics. METHODS: Clinical and dermoscopic images were sourced from a teledermoscopy service database of 13,000 lesions in 7,000 patients. The database was queried for SK, SL or LPLK in sun-exposed sites. Each lesion was evaluated based on specific dermoscopic criteria and the results analyzed. RESULTS: Lesions were identified with mixed clinical and dermoscopic criteria of SK and SL, and in some, dermoscopic criteria for LPLK were also present. CONCLUSIONS: This study highlights the relationship between these lesions. We confirm the term 'benign keratosis' is useful for mixed lesions or for those that are difficult to classify.

6.
Nature ; 614(7946): 108-117, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36653449

RESUMEN

Spontaneous animal behaviour is built from action modules that are concatenated by the brain into sequences1,2. However, the neural mechanisms that guide the composition of naturalistic, self-motivated behaviour remain unknown. Here we show that dopamine systematically fluctuates in the dorsolateral striatum (DLS) as mice spontaneously express sub-second behavioural modules, despite the absence of task structure, sensory cues or exogenous reward. Photometric recordings and calibrated closed-loop optogenetic manipulations during open field behaviour demonstrate that DLS dopamine fluctuations increase sequence variation over seconds, reinforce the use of associated behavioural modules over minutes, and modulate the vigour with which modules are expressed, without directly influencing movement initiation or moment-to-moment kinematics. Although the reinforcing effects of optogenetic DLS dopamine manipulations vary across behavioural modules and individual mice, these differences are well predicted by observed variation in the relationships between endogenous dopamine and module use. Consistent with the possibility that DLS dopamine fluctuations act as a teaching signal, mice build sequences during exploration as if to maximize dopamine. Together, these findings suggest a model in which the same circuits and computations that govern action choices in structured tasks have a key role in sculpting the content of unconstrained, high-dimensional, spontaneous behaviour.


Asunto(s)
Conducta Animal , Refuerzo en Psicología , Recompensa , Animales , Ratones , Cuerpo Estriado/metabolismo , Dopamina/metabolismo , Señales (Psicología) , Optogenética , Fotometría
7.
Cell Rep Med ; 3(11): 100810, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36384093

RESUMEN

Glucagon analogs show promise as components of next-generation, multi-target, anti-obesity therapeutics. The biology of chronic glucagon treatment, in particular, its ability to induce energy expenditure and weight loss, remains poorly understood. Using a long-acting glucagon analog, G108, we demonstrate that glucagon-mediated body weight loss is intrinsically linked to the hypoaminoacidemia associated with its known amino acid catabolic action. Mechanistic studies reveal an energy-consuming response to low plasma amino acids in G108-treated mice, prevented by dietary amino acid supplementation and mimicked by a rationally designed low amino acid diet. Therefore, low plasma amino acids are a pre-requisite for G108-mediated energy expenditure and weight loss. However, preventing hypoaminoacidemia with additional dietary protein does not affect the ability of G108 to improve glycemia or hepatic steatosis in obese mice. These studies provide a mechanism for glucagon-mediated weight loss and confirm the hepatic glucagon receptor as an attractive molecular target for metabolic disease therapeutics.


Asunto(s)
Glucagón , Pérdida de Peso , Ratones , Animales , Glucagón/metabolismo , Metabolismo Energético/fisiología , Receptores de Glucagón/metabolismo , Ratones Obesos , Aminoácidos/farmacología
9.
Lancet Oncol ; 23(3): 428-438, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35240084

RESUMEN

BACKGROUND: Multiparametric MRI of the prostate followed by targeted biopsy is recommended for patients at risk of prostate cancer. However, multiparametric ultrasound is more readily available than multiparametric MRI. Data from paired-cohort validation studies and randomised, controlled trials support the use of multiparametric MRI, whereas the evidence for individual ultrasound methods and multiparametric ultrasound is only derived from case series. We aimed to establish the overall agreement between multiparametric ultrasound and multiparametric MRI to diagnose clinically significant prostate cancer. METHODS: We conducted a prospective, multicentre, paired-cohort, confirmatory study in seven hospitals in the UK. Patients at risk of prostate cancer, aged 18 years or older, with an elevated prostate-specific antigen concentration or abnormal findings on digital rectal examination underwent both multiparametric ultrasound and multiparametric MRI. Multiparametric ultrasound consisted of B-mode, colour Doppler, real-time elastography, and contrast-enhanced ultrasound. Multiparametric MRI included high-resolution T2-weighted images, diffusion-weighted imaging (dedicated high B 1400 s/mm2 or 2000 s/mm2 and apparent diffusion coefficient map), and dynamic contrast-enhanced axial T1-weighted images. Patients with positive findings on multiparametric ultrasound or multiparametric MRI underwent targeted biopsies but were masked to their test results. If both tests yielded positive findings, the order of targeting at biopsy was randomly assigned (1:1) using stratified (according to centre only) block randomisation with randomly varying block sizes. The co-primary endpoints were the proportion of positive lesions on, and agreement between, multiparametric MRI and multiparametric ultrasound in identifying suspicious lesions (Likert score of ≥3), and detection of clinically significant cancer (defined as a Gleason score of ≥4 + 3 in any area or a maximum cancer core length of ≥6 mm of any grade [PROMIS definition 1]) in those patients who underwent a biopsy. Adverse events were defined according to Good Clinical Practice and trial regulatory guidelines. The trial is registered on ISRCTN, 38541912, and ClinicalTrials.gov, NCT02712684, with recruitment and follow-up completed. FINDINGS: Between March 15, 2016, and Nov 7, 2019, 370 eligible patients were enrolled; 306 patients completed both multiparametric ultrasound and multiparametric MRI and 257 underwent a prostate biopsy. Multiparametric ultrasound was positive in 272 (89% [95% CI 85-92]) of 306 patients and multiparametric MRI was positive in 238 patients (78% [73-82]; difference 11·1% [95% CI 5·1-17·1]). Positive test agreement was 73·2% (95% CI 67·9-78·1; κ=0·06 [95% CI -0·56 to 0·17]). Any cancer was detected in 133 (52% [95% CI 45·5-58]) of 257 patients, with 83 (32% [26-38]) of 257 being clinically significant by PROMIS definition 1. Each test alone would result in multiparametric ultrasound detecting PROMIS definition 1 cancer in 66 (26% [95% CI 21-32]) of 257 patients who had biopsies and multiparametric MRI detecting it in 77 (30% [24-36]; difference -4·3% [95% CI -8·3% to -0·3]). Combining both tests detected 83 (32% [95% CI 27-38]) of 257 clinically significant cancers as per PROMIS definition 1; of these 83 cancers, six (7% [95% CI 3-15]) were detected exclusively with multiparametric ultrasound, and 17 (20% [12-31]) were exclusively detected by multiparametric MRI (agreement 91·1% [95% CI 86·9-94·2]; κ=0·78 [95% CI 0·69-0·86]). No serious adverse events were related to trial activity. INTERPRETATION: Multiparametric ultrasound detected 4·3% fewer clinically significant prostate cancers than multiparametric MRI, but it would lead to 11·1% more patients being referred for a biopsy. Multiparametric ultrasound could be an alternative to multiparametric MRI as a first test for patients at risk of prostate cancer, particularly if multiparametric MRI cannot be carried out. Both imaging tests missed clinically significant cancers detected by the other, so the use of both would increase the detection of clinically significant prostate cancers compared with using each test alone. FUNDING: The Jon Moulton Charity Trust, Prostate Cancer UK, and UCLH Charity and Barts Charity.


Asunto(s)
Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias de la Próstata , Humanos , Biopsia Guiada por Imagen/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Clasificación del Tumor , Estudios Prospectivos , Próstata/patología , Antígeno Prostático Específico , Neoplasias de la Próstata/patología
12.
J Med Libr Assoc ; 109(3): 483-489, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34629979

RESUMEN

BACKGROUND: Over a decade ago, the Hill report argued that a shift in vision was required to change the perception of National Health Service (NHS) Library and Knowledge Services (LKS) in England from "book repositories" to essential services that underpin clinical decision-making by patients, carers, and health care professionals. Health Education England's Knowledge for Healthcare: A Development Framework for Library and Knowledge Services in England 2015-2020 advocates embedding librarians within clinical and management teams in order to provide access to high-quality evidence at the point of need. CASE PRESENTATION: In April 2019, Royal Papworth Hospital relocated twelve miles from its historic village location in Papworth Everard to its new state-of-the-art hospital on the Cambridge Biomedical Campus. The design for this new hospital did not accommodate a traditional library space and therefore necessitated a transformation of the LKS. The organization opted to embed the LKS staff into the clinical setting and relegate 80% of the print collection to off-site storage. This project and its associated steps are presented as an example of health care library transformation. CONCLUSION: Embedding the LKS team in the clinical setting, engaging in proactive outreach activity, and improving our marketing led to a 44% increase in literature searches requested compared to the same eleven-month period in the previous year. A 40% decrease in our print book loans indicates additional barriers to using a click-and-collect service and the need for greater investment in our e-book provision. However, early outcomes for our best-fit service transformation are positive. Having an open, dual mindset has enabled the service to embrace change and maximize emerging opportunities to collaborate with clinical staff on new projects.


Asunto(s)
Bibliotecólogos , Bibliotecas Médicas , Inglaterra , Hospitales , Humanos , Medicina Estatal
13.
Hepatology ; 74(6): 3441-3459, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34233024

RESUMEN

BACKGROUND AND AIMS: NAFLD is the most common hepatic pathology in western countries and no treatment is currently available. NAFLD is characterized by the aberrant hepatocellular accumulation of fatty acids in the form of lipid droplets (LDs). Recently, it was shown that liver LD degradation occurs through a process termed lipophagy, a form of autophagy. However, the molecular mechanisms governing liver lipophagy are elusive. Here, we aimed to ascertain the key molecular players that regulate hepatic lipophagy and their importance in NAFLD. APPROACH AND RESULTS: We analyzed the formation and degradation of LD in vitro (fibroblasts and primary mouse hepatocytes), in vivo and ex vivo (mouse and human liver slices) and focused on the role of the autophagy master regulator mammalian target of rapamycin complex (mTORC) 1 and the LD coating protein perilipin (Plin) 3 in these processes. We show that the autophagy machinery is recruited to the LD on hepatic overload of oleic acid in all experimental settings. This led to activation of lipophagy, a process that was abolished by Plin3 knockdown using RNA interference. Furthermore, Plin3 directly interacted with the autophagy proteins focal adhesion interaction protein 200 KDa and autophagy-related 16L, suggesting that Plin3 functions as a docking protein or is involved in autophagosome formation to activate lipophagy. Finally, we show that mTORC1 phosphorylated Plin3 to promote LD degradation. CONCLUSIONS: These results reveal that mTORC1 regulates liver lipophagy through a mechanism dependent on Plin3 phosphorylation. We propose that stimulating this pathway can enhance lipophagy in hepatocytes to help protect the liver from lipid-mediated toxicity, thus offering a therapeutic strategy in NAFLD.


Asunto(s)
Autofagia , Hígado Graso/metabolismo , Hepatocitos/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Perilipina-3/metabolismo , Transducción de Señal , Animales , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL
14.
JVS Vasc Sci ; 2: 2-12, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33842897

RESUMEN

OBJECTIVE: Intimal hyperplasia (IH) is the expansion of the vascular intimal region after intervention, which can lead to stenosis and eventual failure of vascular grafts or interventional procedures such as angioplasty or stent placement. Our goals were to investigate the development of IH in a rabbit open surgical model and to evaluate the associated pathophysiological processes involving decorin and the platelet derived growth factor-BB / platelet derived growth factor receptor-ß / mitogen activated protein kinase (PDGF/PDGFR-ß/MAPK) pathway. METHODS: We conducted carotid transection and primary anastomosis on five New Zealand White rabbits to induce IH and examined the associated pathophysiological changes. Tissue was obtained for histological and protein analysis on post-operative day 21 using the contralateral vessel as a control. Intimal medial thickness (IMT) was calculated to measure IH and compared with the unoperated side. Western blot analysis was performed on tissue lysates to determine the expression of decorin core protein, PDGF-BB, PDGFR-ß, and phosphorylated-MAPK (ph-MAPK). Immunofluorescence microscopy was used to assess tissue distribution of matrix metalloproteinase-2 (MMP-2) and phosphorylated-PDGFR-ß (ph-PDGFR-ß). RESULTS: Bilateral carotid arteries were harvested on postoperative day 21. We compared the IMT in operated with unoperated specimens. IMT was significantly elevated in operated arteries vs. unoperated arteries in all 5 animals (148.6 µm +/- 9.09 vs. 103.40 µm +/- 7.08; 135.2 µm +/- 8.30 vs. 92.40 µm +/- 2.35; 203.1 µm +/- 30.23 vs.104.00 µm +/- 4.52; 236.2 µm +/- 27.22 vs. 141.50 µm +/- 9.95; 226.9 µm +/- 11.12 vs. 98.8 µm +/- 3.78). Western blot analysis revealed degradation of decorin protein in the operated tissue, including loss of a 50 kDa band and the appearance of a cleaved fragment at 10 kDa. Decorin and MMP-2 were observed, via immunofluorescence microscopy, in the neointima of the operated vessels. Western blot analysis also revealed increased PDGF-BB, PDGFR-ß, and ph-MAPK levels in operated tissue. Immunofluorescent staining for ph-PDGFR-ß primarily localized to the neointima, indicating increased signaling through PDGF in this region. CONCLUSION: Carotid transection and primary reanastomosis in rabbits induced IH that was associated with MMP-2 activation, degradation of decorin, and activation of the PDGF/PDGFR-ß /MAPK pathway. The findings in this study should lead to further mechanistic evaluation of these pathways to better understand the potential to modify the intimal hyperplastic response to surgery.

15.
Lancet Infect Dis ; 21(9): 1246-1256, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33857406

RESUMEN

BACKGROUND: Emergence of variants with specific mutations in key epitopes in the spike protein of SARS-CoV-2 raises concerns pertinent to mass vaccination campaigns and use of monoclonal antibodies. We aimed to describe the emergence of the B.1.1.7 variant of concern (VOC), including virological characteristics and clinical severity in contemporaneous patients with and without the variant. METHODS: In this cohort study, samples positive for SARS-CoV-2 on PCR that were collected from Nov 9, 2020, for patients acutely admitted to one of two hospitals on or before Dec 20, 2020, in London, UK, were sequenced and analysed for the presence of VOC-defining mutations. We fitted Poisson regression models to investigate the association between B.1.1.7 infection and severe disease (defined as point 6 or higher on the WHO ordinal scale within 14 days of symptoms or positive test) and death within 28 days of a positive test and did supplementary genomic analyses in a cohort of chronically shedding patients and in a cohort of remdesivir-treated patients. Viral load was compared by proxy, using PCR cycle threshold values and sequencing read depths. FINDINGS: Of 496 patients with samples positive for SARS-CoV-2 on PCR and who met inclusion criteria, 341 had samples that could be sequenced. 198 (58%) of 341 had B.1.1.7 infection and 143 (42%) had non-B.1.1.7 infection. We found no evidence of an association between severe disease and death and lineage (B.1.1.7 vs non-B.1.1.7) in unadjusted analyses (prevalence ratio [PR] 0·97 [95% CI 0·72-1·31]), or in analyses adjusted for hospital, sex, age, comorbidities, and ethnicity (adjusted PR 1·02 [0·76-1·38]). We detected no B.1.1.7 VOC-defining mutations in 123 chronically shedding immunocompromised patients or in 32 remdesivir-treated patients. Viral load by proxy was higher in B.1.1.7 samples than in non-B.1.1.7 samples, as measured by cycle threshold value (mean 28·8 [SD 4·7] vs 32·0 [4·8]; p=0·0085) and genomic read depth (1280 [1004] vs 831 [682]; p=0·0011). INTERPRETATION: Emerging evidence exists of increased transmissibility of B.1.1.7, and we found increased virus load by proxy for B.1.1.7 in our data. We did not identify an association of the variant with severe disease in this hospitalised cohort. FUNDING: University College London Hospitals NHS Trust, University College London/University College London Hospitals NIHR Biomedical Research Centre, Engineering and Physical Sciences Research Council.


Asunto(s)
COVID-19/virología , Genoma Viral , SARS-CoV-2/genética , Índice de Severidad de la Enfermedad , Secuenciación Completa del Genoma , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Londres , Masculino , Persona de Mediana Edad , Filogenia , Reino Unido , Carga Viral , Esparcimiento de Virus
16.
Acta Biomater ; 122: 220-235, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33359292

RESUMEN

Cord blood (CB) mononuclear cell populations have demonstrated significant promise in biomaterials-based regenerative therapies; however, the contributions of monocyte and macrophage subpopulations towards proper tissue healing and regeneration are not well understood, and the phenotypic responses of macrophage to microenvironmental cues have not been well-studied. In this work, we evaluated the effects of cytokine stimulation and altered substrate stiffness. Macrophage derived from CB CD14+ monocytes adopted distinct inflammatory (M1) and anti-inflammatory (M2a and M2c) phenotypes in response to cytokine stimulation (M1: lipopolysaccharide (LPS) and interferon (IFN-γ); M2a: interleukin (IL)-4 and IL-13; M2c: IL-10) as determined through expression of relevant cell surface markers and growth factors. Cytokine-induced macrophage readily altered their phenotypes upon sequential administration of different cytokine cocktails. The impact of substrate stiffness on macrophage phenotype was evaluated by seeding CB-derived macrophage on 3wt%, 6wt%, and 14wt% poly(ethylene glycol)-based hydrogels, which exhibited swollen shear moduli of 0.1, 3.4, and 10.3 kPa, respectively. Surface marker expression and cytokine production varied depending on modulus, with anti-inflammatory phenotypes increasing with elevated substrate stiffness. Integration of specific hydrogel moduli and cytokine cocktail treatments resulted in the differential regulation of macrophage phenotypic biomarkers. These data suggest that CB-derived macrophages exhibit predictable behaviors that can be directed and finely tuned by combinatorial modulation of substrate physical properties and cytokine profiles.


Asunto(s)
Sangre Fetal , Macrófagos , Diferenciación Celular , Citocinas , Fenotipo
17.
Eur J Obstet Gynecol Reprod Biol ; 256: 471-477, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33218821

RESUMEN

OBJECTIVE: The consumption of caffeinated drinks and soft drinks is widespread in society, including by pregnant women. Data regarding the association of caffeine intake and stillbirth are varied. We aimed to investigate the degree of consumption of caffeinated drinks or soft drinks in the last four weeks of pregnancy in women who experienced a late stillbirth compared to women with ongoing live pregnancies at similar gestation. Influences on maternal caffeine intake and soft drink consumption during pregnancy were also investigated. STUDY DESIGN: A case-control study undertaken in 41 maternity units in the United Kingdom. Cases were women who had a singleton non-anomalous stillbirth ≥28 weeks' gestation (n = 290) and controls were women with an ongoing pregnancy at the time of interview (n = 729). Data were collected using an interviewer-administered questionnaire which included questions regarding consumption of a variety of caffeinated drinks and soft drinks in the last four weeks of pregnancy as well as other behaviours (e.g. cigarette smoking). RESULTS: Multivariable analysis adjusting for co-existing demographic and behavioural factors found the consumption of instant coffee, energy drinks and cola were associated with increased risk of stillbirth. There was an independent association between caffeine intake and late stillbirth (adjusted Odds Ratio 1.27, 95 % Confidence Interval (95 %CI) 1.14, 1.43 for each 100 mg increment/day). 15 % of cases and 8% of controls consumed more than the World Health Organisation (WHO) recommendation (>300 mg of caffeine/day; aOR 2.30, 95 % CI 1.40, 4.24). The population attributable risk for stillbirth associated with >300 mg of caffeine/day was 7.4 %. The majority of respondents reduced caffeine consumption in pregnancy. Midwives and internet resources were the most frequently used sources of information which influenced maternal behaviour with regard to soft drinks and caffeine, and this did not differ between cases and controls. CONCLUSIONS: Women should be informed that consumption of caffeine during pregnancy is associated with increased risk of stillbirth, particularly at levels greater than recommended by the WHO (>300 mg/day). Recommendations from midwives and internet-based resources are likely to be the most effective means to influence maternal behaviour.


Asunto(s)
Café , Mortinato , Bebidas Gaseosas , Estudios de Casos y Controles , Café/efectos adversos , Inglaterra/epidemiología , Femenino , Humanos , Masculino , Embarazo , Mortinato/epidemiología , Reino Unido
19.
J Biomater Sci Polym Ed ; 32(5): 635-656, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33231137

RESUMEN

The development of hybrid hydrogels has been of great interest over recent decades, especially in the field of biomaterials. Such hydrogels provide various opportunities in tissue engineering, drug delivery, and regenerative medicine due to their ability to mimic cellular environments, sequester and release therapeutic agents, and respond to stimuli. Herein we report the synthesis and characterization of an injectable poly(ethylene glycol) hydrogel crosslinked via thiol-maleimide reactions and containing both chemically crosslinked temperature-sensitive liposomes (TSLs) and matrix metalloproteinase-sensitive peptide crosslinks. Rheological studies demonstrate that the hydrogel is mechanically stable and can be synthesized to achieve a range of physically applicable moduli. Experiments characterizing the in situ drug delivery and degradation of these materials indicate that the TSL gel responds to both thermal and enzymatic stimuli in a local environment. Doxorubicin, a widely used anticancer drug, was loaded in the TSLs with a high encapsulation efficiency and the subsequent release was temperature dependent. Finally, TSLs did not compromise viability and proliferation of human and murine fibroblasts, supporting the use of these hydrogel-linked liposomes as a thermo-responsive drug carrier for controlled release.


Asunto(s)
Materiales Biocompatibles , Liposomas , Animales , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Humanos , Hidrogeles , Ratones , Polietilenglicoles , Temperatura
20.
PLoS One ; 15(12): e0244243, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33370415

RESUMEN

Adventitial fibroblasts (AFs) are critical mediators of vascular remodeling. However, the contributions of AFs towards development of vasculature and the specific mechanisms by which these cells regulate physiological expansion of the vasa vasorum, the specialized microvasculature that supplies nutrients to the vascular wall, are not well understood. To determine the regulatory role of AFs in microvascular endothelial cell (MVEC) neovasculogenesis and to investigate the regulatory pathways utilized for communication between the two cell types, AFs and MVECs were cultured together in poly(ethylene glycol)-based hydrogels. Following preliminary evaluation of a set of cell adhesion peptides (AG10, AG73, A2G78, YIGSR, RGD), 7.5wt% hydrogels containing 3 mM RGD were selected as these substrates did not initiate primitive tubule structures in 3D MVEC monocultures, thus providing a passive platform to study AF-MVEC interaction. The addition of AFs to hydrogels promoted MVEC viability; however, increasing AF density within hydrogels stimulated MVEC proliferation, increased microvessel density and size, and enhanced deposition of basement membrane proteins, collagen IV and laminin. Importantly, AF-MVEC communication through the transforming growth factor beta (TGF-ß)/activin receptor-like kinase 5 (ALK5) signaling pathway was observed to mediate microvessel formation, as inhibition of ALK5 significantly decreased MVEC proliferation, microvessel formation, mural cell recruitment, and basement membrane production. These data indicate that AFs regulate MVEC neovasculogenesis and suggest that therapeutics targeting the TGF-ß/ALK5 pathway may be useful for regulation of vasculogenic and anti-vasculogenic responses.


Asunto(s)
Aorta/fisiología , Comunicación Celular , Tejido Conectivo/fisiología , Células Endoteliales/fisiología , Fibroblastos/fisiología , Neovascularización Fisiológica , Receptor Tipo I de Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Aorta/citología , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Técnicas de Cocultivo , Células Endoteliales/citología , Fibroblastos/citología , Humanos , Receptor Tipo I de Factor de Crecimiento Transformador beta/genética , Transducción de Señal , Factor de Crecimiento Transformador beta1/genética
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