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1.
Nature ; 632(8025): 564-569, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39085608

RESUMEN

Active basaltic eruptions enable time-series analysis of geochemical and geophysical properties, providing constraints on mantle composition and eruption processes1-4. The continuing Fagradalsfjall and Sundhnúkur fires on Iceland's Reykjanes Peninsula, beginning in 2021, enable such an approach5,6. Earliest lavas of this volcanic episode have been interpreted to exclusively reflect a change from shallow to deeper mantle source processes7. Here we show using osmium (Os) isotopes that the 2021 Fagradalsfjall lavas are both fractionally crystallized and strongly crustally contaminated, probably by mid-ocean-ridge gabbros and older basalts underlying the Reykjanes Peninsula. Earliest eruptive products (187Os/188Os ≤ 0.188, platinum (Pt)/iridium (Ir) ≤ 76) are highly anomalous for Icelandic lavas or global oceanic basalts and Os isotope ratios remain elevated throughout the 2021 eruption, indicating a continued but diluted presence of contaminants. The 2022 lavas show no evidence for contamination (187Os/188Os = 0.131, Pt/Ir = 30), being typical of Icelandic basalts (0.132 ± 0.007). Initiation of the Fagradalsfjall Fires in 2021 involved pre-eruptive stalling, fractional crystallization and crustal assimilation of earliest lavas. An established magmatic conduit system in 2022 enabled efficient magma transit to the surface without crustal assimilation.

2.
Lancet Respir Med ; 12(8): 619-632, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39004091

RESUMEN

BACKGROUND: A small amount of evidence suggests that nasal sprays, or physical activity and stress management, could shorten the duration of respiratory infections. This study aimed to assess the effect of nasal sprays or a behavioural intervention promoting physical activity and stress management on respiratory illnesses, compared with usual care. METHODS: This randomised, controlled, open-label, parallel-group trial was done at 332 general practitioner practices in the UK. Eligible adults (aged ≥18 years) had at least one comorbidity or risk factor increasing their risk of adverse outcomes due to respiratory illness (eg, immune compromise due to serious illness or medication; heart disease; asthma or lung disease; diabetes; mild hepatic impairment; stroke or severe neurological problem; obesity [BMI ≥30 kg/m2]; or age ≥65 years) or at least three self-reported respiratory tract infections in a normal year (ie, any year before the COVID-19 pandemic). Participants were randomly assigned (1:1:1:1) using a computerised system to: usual care (brief advice about managing illness); gel-based spray (two sprays per nostril at the first sign of an infection or after potential exposure to infection, up to 6 times per day); saline spray (two sprays per nostril at the first sign of an infection or after potential exposure to infection, up to 6 times per day); or a brief behavioural intervention in which participants were given access to a website promoting physical activity and stress management. The study was partially masked: neither investigators nor medical staff were aware of treatment allocation, and investigators who did the statistical analysis were unaware of treatment allocation. The sprays were relabelled to maintain participant masking. Outcomes were assessed using data from participants' completed monthly surveys and a survey at 6 months. The primary outcome was total number of days of illness due to self-reported respiratory tract illnesses (coughs, colds, sore throat, sinus or ear infections, influenza, or COVID-19) in the previous 6 months, assessed in the modified intention-to-treat population, which included all randomly assigned participants who had primary outcome data available. Key secondary outcomes were possible harms, including headache or facial pain, and antibiotic use, assessed in all randomly assigned participants. This trial was registered with ISRCTN, 17936080, and is closed to recruitment. FINDINGS: Between Dec 12, 2020, and April 7, 2023, of 19 475 individuals screened for eligibility, 13 799 participants were randomly assigned to usual care (n=3451), gel-based nasal spray (n=3448), saline nasal spray (n=3450), or the digital intervention promoting physical activity and stress management (n=3450). 11 612 participants had complete data for the primary outcome and were included in the primary outcome analysis (usual care group, n=2983; gel-based spray group, n=2935; saline spray group, n=2967; behavioural website group, n=2727). Compared with participants in the usual care group, who had a mean of 8·2 (SD 16·1) days of illness, the number of days of illness was significantly lower in the gel-based spray group (mean 6·5 days [SD 12·8]; adjusted incidence rate ratio [IRR] 0·82 [99% CI 0·76-0·90]; p<0·0001) and the saline spray group (6·4 days [12·4]; 0·81 [0·74-0·88]; p<0·0001), but not in the group allocated to the behavioural website (7·4 days [14·7]; 0·97 [0·89-1·06]; p=0·46). The most common adverse event was headache or sinus pain in the gel-based group: 123 (4·8%) of 2556 participants in the usual care group; 199 (7·8%) of 2498 participants in the gel-based group (risk ratio 1·61 [95% CI 1·30-1·99]; p<0·0001); 101 (4·5%) of 2377 participants in the saline group (0·81 [0·63-1·05]; p=0·11); and 101 (4·5%) of 2091 participants in the behavioural intervention group (0·95 [0·74-1·22]; p=0·69). Compared with usual care, antibiotic use was lower for all interventions: IRR 0·65 (95% CI 0·50-0·84; p=0·001) for the gel-based spray group; 0·69 (0·45-0·88; p=0·003) for the saline spray group; and 0·74 (0·57-0·94; p=0·02) for the behavioural website group. INTERPRETATION: Advice to use either nasal spray reduced illness duration and both sprays and the behavioural website reduced antibiotic use. Future research should aim to address the impact of the widespread implementation of these simple interventions. FUNDING: National Institute for Health and Care Research.


Asunto(s)
COVID-19 , Rociadores Nasales , Atención Primaria de Salud , Humanos , Masculino , Femenino , Persona de Mediana Edad , COVID-19/complicaciones , Adulto , Anciano , Infecciones del Sistema Respiratorio/terapia , SARS-CoV-2 , Reino Unido , Terapia Conductista/métodos , Ejercicio Físico , Estrés Psicológico/terapia
3.
Front Aging Neurosci ; 16: 1350239, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38915346

RESUMEN

The glucagon-like peptide-1 receptor (GLP-1R) agonists reduce glycated hemoglobin in patients with type 2 diabetes. Mounting evidence indicates that the potential of GLP-1R agonists, mimicking a 30 amino acid ligand, GLP-1, extends to the treatment of neurodegenerative conditions, with a particular focus on Alzheimer's disease (AD). However, the mechanism that underlies regulation of GLP-1R availability in the brain with AD remains poorly understood. Here, using whole transcriptome RNA-Seq of the human postmortem caudate nucleus with AD and chronic hydrocephalus (CH) in the elderly, we found that GLP-1R and select mRNAs expressed in glucose dysmetabolism and dyslipidemia were significantly altered. Furthermore, we detected human RNA indicating a deficiency in doublecortin (DCX) levels and the presence of ferroptosis in the caudate nucleus impacted by AD. Using the genome data viewer, we assessed mutability of GLP-1R and 39 other genes by two factors associated with high mutation rates in chromosomes of four species. Surprisingly, we identified that nucleotide sizes of GLP-1R transcript exceptionally differed in all four species of humans, chimpanzees, rats, and mice by up to 6-fold. Taken together, the protein network database analysis suggests that reduced GLP-1R in the aged human brain is associated with glucose dysmetabolism, ferroptosis, and reduced DCX+ neurons, that may contribute to AD.

4.
Sci Adv ; 10(22): eadn9830, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38820147

RESUMEN

Highly siderophile element abundances and Os isotopes of nakhlite and chassignite meteorites demonstrate that they represent a comagmatic suite from Mars. Nakhlites experienced variable assimilation of >2-billion-year-old altered high Re/Os basaltic crust. This basaltic crust is distinct from the ancient crust represented by meteorites Allan Hills 84001 or impact-contaminated Northwest Africa 7034/7533. Nakhlites and chassignites that did not experience crustal assimilation reveal that they were extracted from a depleted lithospheric mantle distinct from the deep plume source of depleted shergottites. The comagmatic origin for nakhlites and chassignites demonstrates a layered martian interior comprising ancient enriched basaltic crust derived from trace element-rich shallow magma ocean cumulates, a variably metasomatized mantle lithosphere, and a trace element-depleted deep mantle sampled by plume magmatism.

5.
J Med Chem ; 67(6): 4655-4675, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38462716

RESUMEN

The ubiquitously expressed protein tyrosine phosphatase SHP2 is required for signaling downstream of receptor tyrosine kinases (RTKs) and plays a role in regulating many cellular processes. Genetic knockdown and pharmacological inhibition of SHP2 suppresses RAS/MAPK signaling and inhibit the proliferation of RTK-driven cancer cell lines. Here, we describe the first reported fragment-to-lead campaign against SHP2, where X-ray crystallography and biophysical techniques were used to identify fragments binding to multiple sites on SHP2. Structure-guided optimization, including several computational methods, led to the discovery of two structurally distinct series of SHP2 inhibitors binding to the previously reported allosteric tunnel binding site (Tunnel Site). One of these series was advanced to a low-nanomolar lead that inhibited tumor growth when dosed orally to mice bearing HCC827 xenografts. Furthermore, a third series of SHP2 inhibitors was discovered binding to a previously unreported site, lying at the interface of the C-terminal SH2 and catalytic domains.


Asunto(s)
Neoplasias , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Humanos , Ratones , Animales , Transducción de Señal , Proteínas Tirosina Quinasas Receptoras/metabolismo , Sitio Alostérico
6.
Br J Gen Pract ; 74(743): e379-e386, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38316467

RESUMEN

BACKGROUND: Two online behavioural interventions (one website for parents/carers of children with eczema; and one for young people with eczema) have been shown in randomised controlled trials to facilitate a sustained improvement in eczema severity. AIM: To describe intervention use and examine potential mediators of intervention outcomes and contextual factors that may influence intervention delivery and outcomes. DESIGN AND SETTING: Quantitative process evaluation in UK primary care. METHOD: Parents/carers and young people were recruited through primary care. Intervention use was recorded and summarised descriptively. Logistic regression explored sociodemographic and other factors associated with intervention engagement. Mediation analysis investigated whether patient enablement (ability to understand and cope with health issues), treatment use, and barriers to adherence were mediators of intervention effect. Subgroup analysis compared intervention effects among pre-specified participant subsets. RESULTS: A total of 340 parents/carers and 337 young people were recruited. Most parents/carers (87%, n = 148/171) and young people (91%, n = 153/168) in the intervention group viewed the core introduction by 24 weeks. At 24 weeks, users had spent approximately 20 minutes on average on the interventions. Among parents/carers, greater intervention engagement was associated with higher education levels, uncertainty about carrying out treatments, and doubts about treatment efficacy at baseline. Among young people, higher intervention use was associated with higher baseline eczema severity. Patient enablement (the ability to understand and cope with health issues) accounted for approximately 30% of the intervention effect among parents/carers and 50% among young people. CONCLUSION: This study demonstrated that positive intervention outcomes depended on a modest time commitment from users. This provides further support that the wider implementation of Eczema Care Online is justified.


Asunto(s)
Eccema , Padres , Humanos , Eccema/terapia , Masculino , Femenino , Niño , Adolescente , Padres/psicología , Cuidadores/psicología , Cuidadores/educación , Reino Unido , Terapia Conductista , Preescolar , Internet , Atención Primaria de Salud , Intervención basada en la Internet , Adaptación Psicológica , Adulto , Resultado del Tratamiento
8.
Med Phys ; 51(4): 2479-2498, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37967277

RESUMEN

BACKGROUND: Contrast-enhanced spectral mammography (CESM) with photon-counting x-ray detectors (PCDs) can be used to improve the classification of breast cancers as benign or malignant. Commercially-available PCD-based mammography systems use silicon-based PCDs. Cadmium-telluride (CdTe) PCDs may provide a practical advantage over silicon-based PCDs because they can be implemented as large-area detectors that are more easily adaptable to existing mammography systems. PURPOSE: The purpose of this work is to optimize CESM implemented with CdTe PCDs and to investigate the influence of the number of energy bins, electronic noise level, pixel size, and anode material on image quality. METHODS: We developed a Monte Carlo model of the energy-bin-dependent modulation transfer functions (MTFs) and noise power spectra, including spatioenergetic noise correlations. We validated model predictions using a CdTe PCD with analog charge summing for charge-sharing suppression. Using the ideal-observer detectability, we optimized CESM for the task of detecting a 7-mm-diameter iodine nodule embedded in a breast with 50% glandularity. We optimized the tube voltage, beam filtration, and the location of energy thresholds for 50 and 100- µ $\mu$ m pixels, tungsten and molybdenum anodes, and two electronic noise levels. One of the electronic noise levels was that of the experimental system; the other was half that of the experimental system. Optimization was performed for CdTe PCDs with two or three energy bins. We also estimated the impact of anatomic noise due to background parenchymal enhancement and computed the minimum detectable iodine area density in the presence of quantum and anatomic noise. RESULTS: Model predictions of the MTFs and noise power spectra agreed well with experiment. For optimized systems, adding a third energy bin increased quantum noise levels and reduced detectability by ∼55% compared to two-bin approaches that simply suppress contrast between fibroglandular and adipose tissue. Decreasing the electronic noise standard deviation from 3.4 to 1.7 keV increased iodine detectability by ∼5% and ∼30% for two-bin imaging and three-bin imaging, respectively. After optimizing for tube voltage, beam filtration, and the location of energy thresholds, there was ∼a 3% difference in iodine detectability between molybdenum and tungsten anodes for two-bin imaging, but for three-bin imaging, molybdenum anodes provided up to 14% increase in detectability relative to tungsten anodes. Anatomic noise decreased iodine detectability by 15% to 40%, with greater impact for lower electronic noise settings and larger pixel sizes. CONCLUSIONS: For CESM implemented with CdTe PCDs, (1) quantitatively-accurate three-material decompositions using three energy bins are associated with substantial increases in quantum noise relative to two-energy-bin approaches that simply suppress contrast between fibroglandular and adipose tissues; (2) tungsten and molybdenum anodes can provide nearly equal iodine detectability for two-bin imaging, but molybdenum provides a modest detectability advantage for three-bin imaging provided that all other technique parameters are optimized; (3) reducing pixel sizes from 100 to 50  µ $\mu$ m can reduce detectability by up to 20% due to charge sharing; (4) anatomic noise due to background parenchymal enhancement is estimated to have a substantial impact on lesion visibility, reducing detectability by approximately 30%.


Asunto(s)
Compuestos de Cadmio , Yodo , Puntos Cuánticos , Rayos X , Telurio , Tomografía Computarizada por Rayos X/métodos , Molibdeno , Silicio , Tungsteno , Mamografía , Fotones
9.
Implement Sci ; 18(1): 67, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38049846

RESUMEN

BACKGROUND: Germ Defence ( www.germdefence.org ) is an evidence-based interactive website that promotes behaviour change for infection control within households. To maximise the potential of Germ Defence to effectively reduce the spread of COVID-19, the intervention needed to be implemented at scale rapidly. METHODS: With NHS England approval, we conducted an efficient two-arm (1:1 ratio) cluster randomised controlled trial (RCT) to examine the effectiveness of randomising implementation of Germ Defence via general practitioner (GP) practices across England, UK, compared with usual care to disseminate Germ Defence to patients. GP practices randomised to the intervention arm (n = 3292) were emailed and asked to disseminate Germ Defence to all adult patients via mobile phone text, email or social media. Usual care arm GP practices (n = 3287) maintained standard management for the 4-month trial period and then asked to share Germ Defence with their adult patients. The primary outcome was the rate of GP presentations for respiratory tract infections (RTI) per patient. Secondary outcomes comprised rates of acute RTIs, confirmed COVID-19 diagnoses and suspected COVID-19 diagnoses, COVID-19 symptoms, gastrointestinal infection diagnoses, antibiotic usage and hospital admissions. The impact of the intervention on outcome rates was assessed using negative binomial regression modelling within the OpenSAFELY platform. The uptake of the intervention by GP practice and by patients was measured via website analytics. RESULTS: Germ Defence was used 310,731 times. The average website satisfaction score was 7.52 (0-10 not at all to very satisfied, N = 9933). There was no evidence of a difference in the rate of RTIs between intervention and control practices (rate ratio (RR) 1.01, 95% CI 0.96, 1.06, p = 0.70). This was similar to all other eight health outcomes. Patient engagement within intervention arm practices ranged from 0 to 48% of a practice list. CONCLUSIONS: While the RCT did not demonstrate a difference in health outcomes, we demonstrated that rapid large-scale implementation of a digital behavioural intervention is possible and can be evaluated with a novel efficient prospective RCT methodology analysing routinely collected patient data entirely within a trusted research environment. TRIAL REGISTRATION: This trial was registered in the ISRCTN registry (14602359) on 12 August 2020.


Asunto(s)
COVID-19 , Medicina General , Infecciones del Sistema Respiratorio , Adulto , Humanos , Inglaterra , Atención Primaria de Salud
11.
PLoS One ; 18(7): e0285693, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37450460

RESUMEN

BACKGROUND: Most adults in the UK experience at least one viral respiratory tract infection (RTI) per year. Individuals with comorbidities and those with recurrent RTIs are at higher risk of infections. This can lead to more severe illness, worse quality of life and more days off work. There is promising evidence that using common nasal sprays or improving immune function through increasing physical activity and managing stress, may reduce the incidence and severity of RTIs. METHODS AND DESIGN: Immune Defence is an open, parallel group, randomised controlled trial. Up to 15000 adults from UK general practices, with a comorbidity or risk factor for infection and/or recurrent infections (3 or more infections per year) will be randomly allocated to i) a gel-based nasal spray designed to inhibit viral respiratory infections; ii) a saline nasal spray, iii) a digital intervention promoting physical activity and stress management, or iv) usual care with brief advice for managing infections, for 12 months. Participants will complete monthly questionnaires online. The primary outcome is the total number of days of illness due to RTIs over 6 months. Key secondary outcomes include: days with symptoms moderately bad or worse; days where work/normal activities were impaired; incidence of RTI; incidence of COVID-19; health service contacts; antibiotic usage; beliefs about antibiotics; intention to consult; number of days of illness in total due to respiratory tract infections over 12 months. Economic evaluation from an NHS perspective will compare the interventions, expressed as incremental cost effectiveness ratios. A nested mixed methods process evaluation will examine uptake and engagement with the interventions and trial procedures. TRIAL STATUS: Recruitment commenced in December 2020 and the last participant is expected to complete the trial in April 2024. DISCUSSION: Common nasal sprays and digital interventions to promote physical activity and stress management are low cost, accessible interventions applicable to primary care. If effective, they have the potential to reduce the individual and societal impact of RTIs. TRIAL REGISTRATION: Prospectively registered with ISRCTN registry (17936080) on 30/10/2020. SPONSOR: This RCT is sponsored by University of Southampton. The sponsors had no role in the study design, decision to publish, or preparation of the manuscript.


Asunto(s)
COVID-19 , Infecciones del Sistema Respiratorio , Adulto , Humanos , Rociadores Nasales , Análisis Costo-Beneficio , Calidad de Vida , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/prevención & control , Atención Primaria de Salud , Ejercicio Físico , Ensayos Clínicos Controlados Aleatorios como Asunto
12.
PLOS Digit Health ; 2(6): e0000274, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37347727

RESUMEN

Digital interventions are increasingly recognised as cost-effective treatment solutions for a number of health concerns, but adoption and use of these interventions can be low, affecting outcomes. This research sought to identify how individual aesthetic facets and perceived trust may influence perceptions toward and intentions to use an online health intervention by building on the Technology Acceptance Model, where perceived attractiveness, perceived usefulness, perceived ease of use and perceived enjoyment are thought to predict behavioural intentions towards a website. An online questionnaire study assessed perceptions of nine stimuli varying in four aesthetic facets (simplicity, diversity, colour & craftsmanship), utilising a quasi-experimental within-subjects design with a repetition among three different groups: individuals from the general population who were shown stimuli referring to general health (GP-H) (N = 257); individuals experiencing an eating disorder and shown stimuli referring to eating disorders (ED-ED) (N = 109); and individuals from the general population who were shown stimuli referring to eating disorders (GP-ED) (N = 235). Linear mixed models demonstrated that perceptions of simplicity and craftsmanship significantly influenced perceptions of usefulness, ease of use, enjoyment and trust, which in turn influenced behavioural intentions. This study demonstrates that developing the TAM model to add a further construct of perceived trust could be beneficial for digital health intervention developers. In this study, simplicity and craftsmanship were identified as the aesthetic facets with the greatest impact on user perceptions of digital health interventions.

13.
Bioengineering (Basel) ; 10(5)2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37237620

RESUMEN

Transplantation of allogeneic donor ovarian tissue holds great potential for female cancer survivors who often experience premature ovarian insufficiency. To avoid complications associated with immune suppression and to protect transplanted ovarian allografts from immune-mediated injury, we have developed an immunoisolating hydrogel-based capsule that supports the function of ovarian allografts without triggering an immune response. Encapsulated ovarian allografts implanted in naïve ovariectomized BALB/c mice responded to the circulating gonadotropins and maintained function for 4 months, as evident by regular estrous cycles and the presence of antral follicles in the retrieved grafts. In contrast to non-encapsulated controls, repeated implantations of encapsulated mouse ovarian allografts did not sensitize naïve BALB/c mice, which was confirmed with undetectable levels of alloantibodies. Further, encapsulated allografts implanted in hosts previously sensitized by the implantation of non-encapsulated allografts restored estrous cycles similarly to our results in naïve recipients. Next, we tested the translational potential and efficiency of the immune-isolating capsule in a rhesus monkey model by implanting encapsulated ovarian auto- and allografts in young ovariectomized animals. The encapsulated ovarian grafts survived and restored basal levels of urinary estrone conjugate and pregnanediol 3-glucuronide during the 4- and 5-month observation periods. We demonstrate, for the first time, that encapsulated ovarian allografts functioned for months in young rhesus monkeys and sensitized mice, while the immunoisolating capsule prevented sensitization and protected the allograft from rejection.

14.
Br J Anaesth ; 131(1): 56-66, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37117099

RESUMEN

BACKGROUND: Little is known about the opportunities for shared decision-making when older high-risk patients are offered major surgery. This study examines how, when, and why clinicians and patients can share decision-making about major surgery. METHODS: This was a multi-method qualitative study, combining video recordings of preoperative consultations, interviews, and focus groups (33 patients, 19 relatives, 36 clinicians), with observations and documentary analysis in clinics in five hospitals in the UK undertaking major orthopaedic, colorectal, and/or cardiac surgery. RESULTS: Three opportunities for shared decision-making about major surgery were identified. Resolution-focused consultations (cardiac/colorectal) resulted in a single agreed preferred option related to a potentially life-threatening problem, with limited opportunities for shared decision-making. Evaluative and deliberative consultations offered more opportunity. The former focused on assessing the likelihood of benefits of surgery for a presenting problem that was not a threat to life for the patient (e.g., orthopaedic consultations) and the latter (largely colorectal) involved discussion of a range of options while also considering significant comorbidities and patient preferences. The extent to which opportunities for shared decision-making were available, and taken up by surgeons, was influenced by the nature of the presenting problem, clinical pathway, and patient trajectory. CONCLUSIONS: Decisions about major surgery were not always shared between patients and doctors. The nature of the presenting problem, comorbidities, clinical pathways, and patient trajectories all informed the type of consultation and opportunities for sharing decision-making. Our findings have implications for clinicians, with shared decision-making about major surgery most feasible when the focus is on life-enhancing treatment.


Asunto(s)
Neoplasias Colorrectales , Cirujanos , Humanos , Toma de Decisiones , Toma de Decisiones Conjunta , Grabación en Video , Participación del Paciente , Relaciones Médico-Paciente
15.
Int J Mol Sci ; 24(5)2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36902373

RESUMEN

The repair of orthopedic and maxillofacial defects in modern medicine currently relies heavily on the use of autograft, allograft, void fillers, or other structural material composites. This study examines the in vitro osteo regenerative potential of polycaprolactone (PCL) tissue scaffolding, fabricated via a three-dimensional (3D) additive manufacturing technology, i.e., a pneumatic micro extrusion (PME) process. The objectives of this study were: (i) To examine the innate osteoinductive and osteoconductive potential of 3D-printed PCL tissue scaffolding and (ii) To perform a direct in vitro comparison of 3D-printed PCL scaffolding with allograft Allowash® cancellous bone cubes with regards to cell-scaffold interactions and biocompatibility with three primary human bone marrow (hBM) stem cell lines. This study specifically examined cell survival, cell integration, intra-scaffold cell proliferation, and differentiation of progenitor cells to investigate the potential of 3D-printed PCL scaffolds as an alternative to allograft bone material for the repair of orthopedic injuries. We found that mechanically robust PCL bone scaffolds can be fabricated via the PME process and the resulting material did not elicit detectable cytotoxicity. When the widely used osteogenic model SAOS-2 was cultured in PCL extract medium, no detectable effect was observed on cell viability or proliferation with multiple test groups showing viability ranges of 92.2% to 100% relative to a control group with a standard deviation of ±10%. In addition, we found that the honeycomb infill pattern of the 3D-printed PCL scaffold allowed for superior mesenchymal stem-cell integration, proliferation, and biomass increase. When healthy and active primary hBM cell lines, having documented in vitro growth rates with doubling times of 23.9, 24.67, and 30.94 h, were cultured directly into 3D-printed PCL scaffolds, impressive biomass increase values were observed. It was found that the PCL scaffolding material allowed for biomass increase values of 17.17%, 17.14%, and 18.18%, compared to values of 4.29% for allograph material cultured under identical parameters. It was also found that the honeycomb scaffold infill pattern was superior to the cubic and rectangular matrix structures, and provided a superior microenvironment for osteogenic and hematopoietic progenitor cell activity and auto-differentiation of primary hBM stem cells. Histological and immunohistochemical studies performed in this work confirmed the regenerative potential of PCL matrices in the orthopedic setting by displaying the integration, self-organization, and auto-differentiation of hBM progenitor cells within the matrix. Differentiation products including mineralization, self-organizing "proto-osteon" structures, and in vitro erythropoiesis were observed in conjunction with the documented expression of expected bone marrow differentiative markers including CD-99 (>70%), CD-71 (>60%), and CD-61 (>5%). All of the studies were conducted without the addition of any exogenous chemical or hormonal stimulation and exclusively utilized the abiotic and inert material polycaprolactone; setting this work apart from the vast majority of contemporary investigations into synthetic bone scaffold fabrication In summary, this study demonstrates the unique clinical potential of 3D-printed PCL scaffolds for stem cell expansion and incorporation into advanced microstructures created via PME manufacturing to generate a physiologically inert temporary bony defect graft with significant autograft features for enhanced end-stage healing.


Asunto(s)
Caproatos , Células Madre Mesenquimatosas , Andamios del Tejido , Humanos , Células de la Médula Ósea , Caproatos/farmacología , Osteogénesis , Poliésteres/química , Impresión Tridimensional , Ingeniería de Tejidos/métodos , Andamios del Tejido/química
16.
J Radiol Nurs ; 42(1): 77-84, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36742420

RESUMEN

Introduction: Point-of-care ultrasound (POCUS) has enhanced patient care and safety around the world. Clinicians can now use a small diagnostic ultrasound imaging device to answer some binary clinical questions and manage patients more effectively. Since the COVID-19 pandemic, there has been a significant adoption of POCUS by clinicians worldwide. Materials and Methods: A basic cardiac POCUS training was conducted in Haiti with focus on physics, instrumentation, and basic echocardiography. Results: The Mission POCUS team trained 15 Haitian physicians interested in better serving their patients with the implementation of POCUS cardiac in their patient assessment. Conclusion: POCUS skills will empower clinicians from around the world to make rapid and accurate diagnosis and help save lives by diagnosing life threatening conditions and manage patient appropriately. Our experience in Haiti showed that a short POCUS training course can help improve the knowledge of physicians.

17.
Nat Commun ; 13(1): 7594, 2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36494367

RESUMEN

Sample return missions have provided the basis for understanding the thermochemical evolution of the Moon. Mare basalt sources are likely to have originated from partial melting of lunar magma ocean cumulates after solidification from an initially molten state. Some of the Apollo mare basalts show evidence for the presence in their source of a late-stage radiogenic heat-producing incompatible element-rich layer, known for its enrichment in potassium, rare-earth elements, and phosphorus (KREEP). Here we show the most depleted lunar meteorite, Asuka-881757, and associated mare basalts, represent ancient (~3.9 Ga) partial melts of KREEP-free Fe-rich mantle. Petrological modeling demonstrates that these basalts were generated at lower temperatures and shallower depths than typical Apollo mare basalts. Calculated mantle potential temperatures of these rocks suggest a relatively cooler mantle source and lower surface heat flow than those associated with later-erupted mare basalts, suggesting a fundamental shift in melting regime in the Moon from ~3.9 to ~3.3 Ga.


Asunto(s)
Meteoroides , Luna , Animales , Femenino , Caballos , Silicatos , Estro
18.
Sci Rep ; 12(1): 19764, 2022 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-36396724

RESUMEN

Appendicoliths are commonly found obstructing the lumen of the appendix at the time of appendectomy. To identify factors that might contribute to their formation we investigated the composition of appendicoliths using laser ablation inductively coupled plasma mass spectroscopy, gas chromatography, polarized light microscopy, X-ray crystallography and protein mass spectroscopy. Forty-eight elements, 32 fatty acids and 109 human proteins were identified within the appendicoliths. The most common elements found in appendicoliths are calcium and phosphorus, 11.0 ± 6.0 and 8.2 ± 4.2% weight, respectively. Palmitic acid (29.7%) and stearate (21.3%) are the most common fatty acids. Some stearate is found in crystalline form-identifiable by polarized light microscopy and confirmable by X-ray crystallography. Appendicoliths have an increased ratio of omega-6 to omega-3 fatty acids (ratio 22:1). Analysis of 16 proteins common to the appendicoliths analyzed showed antioxidant activity and neutrophil functions (e.g. activation and degranulation) to be the most highly enriched pathways. Considered together, these preliminary findings suggest oxidative stress may have a role in appendicolith formation. Further research is needed to determine how dietary factors such as omega-6 fatty acids and food additives, redox-active metals and the intestinal microbiome interact with genetic factors to predispose to appendicolith formation.


Asunto(s)
Apéndice , Ácidos Grasos , Humanos , Estearatos , Apendicectomía , Cromatografía de Gases
19.
Front Public Health ; 10: 962873, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36203694

RESUMEN

Introduction: Multidomain interventions to address modifiable risk factors for dementia are promising, but require more cost-effective, scalable delivery. This study investigated the feasibility of the "Active Brains" digital behavior change intervention and its trial procedures. Materials and methods: Active Brains aims to reduce cognitive decline by promoting physical activity, healthy eating, and online cognitive training. We conducted 12-month parallel-design randomized controlled feasibility trials of "Active Brains" amongst "lower cognitive scoring" (n = 180) and "higher cognitive scoring" (n = 180) adults aged 60-85. Results: We collected 67.2 and 76.1% of our 12-month primary outcome (Baddeley verbal reasoning task) data for the "lower cognitive score" and "higher cognitive score" groups, respectively. Usage of "Active Brains" indicated overall feasibility and satisfactory engagement with the physical activity intervention content (which did not require sustained online engagement), but engagement with online cognitive training was limited. Uptake of the additional brief telephone support appeared to be higher in the "lower cognitive score" trial. Preliminary descriptive trends in the primary outcome data might indicate a protective effect of Active Brains against cognitive decline, but further investigation in fully-powered trials is required to answer this definitively. Discussion: Whilst initial uptake and engagement with the online intervention was modest, it was in line with typical usage of other digital behavior change interventions, and early indications from the descriptive analysis of the primary outcome and behavioral data suggest that further exploration of the potential protective benefits of Active Brains are warranted. The study also identified minor modifications to procedures, particularly to improve online primary-outcome completion. Further investigation of Active Brains will now seek to determine its efficacy in protecting cognitive performance amongst adults aged 60-85 with varied levels of existing cognitive performance.


Asunto(s)
Disfunción Cognitiva , Encéfalo , Cognición , Disfunción Cognitiva/prevención & control , Disfunción Cognitiva/psicología , Ejercicio Físico , Estudios de Factibilidad , Humanos
20.
Org Biomol Chem ; 20(37): 7483-7490, 2022 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-36102876

RESUMEN

This article discusses the reactivity of 6-azaindazole (1) and 2,6-naphthyridine (2), proposed to be "heteroaromatic rings of the future," which would be useful for fragment-based drug discovery (FBDD) campaigns, developing growth vectors for fragment elaboration by selectively functionalizing different positions on the rings. The pyridone oxygens and pyrazole nitrogen can be functionalized selectively. Arylation at the α-carbon of the pyridone moiety was achieved by a transition metal-free radical cross-coupling using aryl hydrazines. This method proceeded under mild conditions without the need for protection of the hydroxypyridine. Additionally, we developed a method for the regioselective C-3 functionalization of heterocycle 1via N-sulfonamide rearrangement. This method involved a novel regioselective base-mediated N-C migration of the N-1 sulfonamide to yield the C-3 sulfone. This procedure is also applicable for indazole C-3 functionalization and mechanistic studies of the rearrangement suggest that an intermolecular process is involved. These reactions enable the fragment elaboration of heterocycles 1 and 2 in several growth vectors to facilitate their use in FBDD.


Asunto(s)
Carbono , Nitrógeno , Catálisis , Hidrazinas , Indazoles , Naftiridinas , Pirazoles , Piridonas , Sulfonamidas , Sulfonas
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