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1.
J Chem Phys ; 160(14)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38591679

RESUMO

The crystallization process of methane hydrates in a confined geometry resembling seabed porous silica sedimentary conditions has been studied using molecular dynamics simulations. With this objective in mind, a fully atomistic quartz silica slit pore has been designed, and the temperature stability of a methane hydrate crystalline seed in the presence of water and guest molecule methane has been analyzed. NaCl ion pairs have been added in different concentrations, simulating salinity conditions up to values higher than average oceanic conditions. The structure obtained when the hydrate crystallizes inside the pore is discussed, paying special attention to the presence of ionic doping inside the hydrate and the subsequent induced structural distortion. The shift in the hydrate stability conditions due to the increasing water salinity is discussed and compared with the case of unconfined hydrate, concluding that the influence of the confinement geometry and pore hydrophilicity produces a larger deviation in the confined hydrate phase equilibria.

2.
J Synchrotron Radiat ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38587894

RESUMO

The Materials Imaging and Dynamics (MID) instrument at the European X-ray Free-Electron Laser Facility (EuXFEL) is equipped with a multipurpose diagnostic end-station (DES) at the end of the instrument. The imager unit in DES is a key tool for aligning the beam to a standard trajectory and for adjusting optical elements such as focusing lenses or the split-and-delay line. Furthermore, the DES features a bent-diamond-crystal spectrometer to disperse the spectrum of the direct beam to a line detector. This enables pulse-resolved characterization of the EuXFEL spectrum to provide X-ray energy calibration, and the spectrometer is particularly useful in commissioning special modes of the accelerator. Together with diamond-based intensity monitors, the imager and spectrometer form the DES unit which also contains a heavy-duty beamstop at the end of the MID instrument. Here, we describe the setup in detail and provide exemplary beam diagnostic results.

3.
Sci Adv ; 10(16): eadm7876, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640237

RESUMO

Stimuli-responsive polymers are an important class of materials with many applications in nanotechnology and drug delivery. The most prominent one is poly-N-isopropylacrylamide (PNIPAm). The characterization of the kinetics of its change after a temperature jump is still a lively research topic, especially at nanometer-length scales where it is not possible to rely on conventional microscopic techniques. Here, we measured in real time the collapse of a PNIPAm shell on silica nanoparticles with megahertz x-ray photon correlation spectroscopy at the European XFEL. We characterize the changes of the particles diffusion constant as a function of time and consequently local temperature on sub-microsecond timescales. We developed a phenomenological model to describe the observed data and extract the characteristic times associated to the swelling and collapse processes. Different from previous studies tracking the turbidity of PNIPAm dispersions and using laser heating, we find collapse times below microsecond timescales and two to three orders of magnitude slower swelling times.

4.
Nutrients ; 16(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38542815

RESUMO

Exercise can disrupt the fluid balance, hindering performance and athlete health. Limited data exist on fluid balance responses in varying climates, sexes, and ages. This study aimed to measure and compare fluid balance and urine values among elite soccer players during training at high and low temperatures, examining the differences between sexes, playing positions, and competitive levels within men's soccer. During the 2022-2023 competitive season, a descriptive observational study was conducted on 87 soccer players from an elite Spanish soccer team. The study found that none of the groups exceeded weight loss values of 1.5% of their body mass. Additionally, the soccer players studied experienced higher weight loss, fluid intake, and a higher sweat rate (SR) during summer training compared to winter training. During the summer, male U23-21 soccer players exhibited higher levels of weight loss, fluid intake, and a higher SR compared to female soccer players or the U19-17 male category. No significant differences were found between playing positions. In conclusion, differences in the fluid balance were observed based on the climatic conditions, competitive level, and sex.


Assuntos
Futebol , Humanos , Masculino , Feminino , Futebol/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Suor , Sudorese , Redução de Peso
5.
bioRxiv ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38463969

RESUMO

Background and aims: Pancreatic ducts form an intricate network of tubules that secrete bicarbonate and drive acinar secretions into the duodenum. This network is formed by centroacinar cells, terminal, intercalated, intracalated ducts, and the main pancreatic duct. Ductal heterogeneity at the single-cell level has been poorly characterized; therefore, our understanding of the role of ductal cells in pancreas regeneration and exocrine pathogenesis has been hampered by the limited knowledge and unexplained diversity within the ductal network. Methods: We used scRNA-seq to comprehensively characterize mouse ductal heterogeneity at single-cell resolution of the entire ductal epithelium from centroacinar cells to the main duct. Moreover, we used organoid cultures, injury models and pancreatic tumor samples to interrogate the role of novel ductal populations in pancreas regeneration and exocrine pathogenesis. Results: We have identified the coexistence of 15 ductal populations within the healthy pancreas and characterized their organoid formation capacity and endocrine differentiation potential. Cluster isolation and subsequent culturing let us identify ductal cell populations with high organoid formation capacity and endocrine and exocrine differentiation potential in vitro , including Wnt-responsive-population, ciliated-population and FLRT3 + cells. Moreover, we have characterized the location of these novel ductal populations in healthy pancreas, chronic pancreatitis, and tumor samples, highlighting a putative role of WNT-responsive, IFN-responsive and EMT-populations in pancreatic exocrine pathogenesis as their expression increases in chronic pancreatitis and PanIN lesions. Conclusions: In light of our discovery of previously unidentified ductal populations, we unmask the potential roles of specific ductal populations in pancreas regeneration and exocrine pathogenesis.

6.
Sci Transl Med ; 16(734): eadg7962, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38354229

RESUMO

Multiple myeloma is the second most common hematological malignancy in adults and remains an incurable disease. B cell maturation antigen (BCMA)-directed immunotherapy, including T cells bearing chimeric antigen receptors (CARs) and systemically injected bispecific T cell engagers (TCEs), has shown remarkable clinical activity, and several products have received market approval. However, despite promising results, most patients eventually become refractory and relapse, highlighting the need for alternative strategies. Engineered T cells secreting TCE antibodies (STAb) represent a promising strategy that combines the advantages of adoptive cell therapies and bispecific antibodies. Here, we undertook a comprehensive preclinical study comparing the therapeutic potential of T cells either expressing second-generation anti-BCMA CARs (CAR-T) or secreting BCMAxCD3 TCEs (STAb-T) in a T cell-limiting experimental setting mimicking the conditions found in patients with relapsed/refractory multiple myeloma. STAb-T cells recruited T cell activity at extremely low effector-to-target ratios and were resistant to inhibition mediated by soluble BCMA released from the cell surface, resulting in enhanced cytotoxic responses and prevention of immune escape of multiple myeloma cells in vitro. These advantages led to robust expansion and persistence of STAb-T cells in vivo, generating long-lived memory BCMA-specific responses that could control multiple myeloma progression in xenograft models, outperforming traditional CAR-T cells. These promising preclinical results encourage clinical testing of the BCMA-STAb-T cell approach in relapsed/refractory multiple myeloma.


Assuntos
Mieloma Múltiplo , Receptores de Antígenos Quiméricos , Adulto , Humanos , Mieloma Múltiplo/patologia , Linfócitos T , Imunoterapia Adotiva/métodos , Antígeno de Maturação de Linfócitos B , Memória Imunológica , Recidiva Local de Neoplasia/metabolismo , Receptores de Antígenos Quiméricos/metabolismo
7.
Healthcare (Basel) ; 12(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38338265

RESUMO

Purpose. This study aimed to: (a) translate and cross-culturally adapt the Hammersmith Infant Neurological Examination (HINE) into Spanish; (b) evaluate its intra- and inter-examiner reliability; (c) support a knowledge translation and tool implementation program in early intervention; and (d) evaluate its reliability and implementation for professionals one year after receiving training. Materials and methods. The translation followed the World Health Organization's recommendations. Reliability was assessed in 25 infants aged between 3 and 15 months with identifiable risks of cerebral palsy (CP). The implementation was also evaluated by analyzing the reliability of professionals without previous experience of the tool by using a pre-survey and a follow-up survey one year after training. The survey covered aspects related to the use of early detection tools of CP and the use of HINE, including attitudes, opinions, and perceptions. Results. An excellent intra- and inter-examiner agreement was obtained for the total score of the HINE intra-class correlation coefficient (ICC = 0.98 in both indices). One year after training, the professionals also showed excellent reliability values (ICC = 0.99), as well as an increase in sensitization and skills in evidence-based practices for the early detection of "high risk" of CP. Conclusions. The Spanish version of HINE is a reliable measure for the neurological evaluation of "high risk" of CP and can be administered after standardized training and without costs to acquire the evaluation. This allows its accessible and widespread implementation in the clinical context.

8.
Anaesth Crit Care Pain Med ; 43(2): 101346, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38278357

RESUMO

BACKGROUND: Transesophageal echocardiogram probe insertion in intubated critically ill patients can be difficult, leading to complications, such as gastric bleeding or lesions in the oropharyngeal mucosa. We hypothesised that the use of a videolaryngoscope would facilitate the first attempt at insertion of the transesophageal echocardiogram probe and would decrease the incidence of complications compared to the conventional insertion technique. METHODS: In this clinical trial, patients were randomly assigned the insertion of a transesophageal echocardiogram probe using a videolaryngoscope or conventional technique. The primary outcome was the successful transesophageal echocardiogram probe insertion on the first attempt. The secondary outcomes included total success rate, number of insertion attempts, and incidence of pharyngeal complications. RESULTS: A total of 100 intubated critically ill patients were enrolled. The success rate of transesophageal echocardiogram probe insertion on the first attempt was higher in the videolaryngoscope group than in the conventional group (90% vs. 58%; absolute difference, 32%; 95% CI 16%-48%; p < 0.001). The overall success rate was higher in the videolaryngoscope group than in the conventional group (100% vs. 72%; absolute difference, 28%; 95% CI 16%-40%; p < 0.001). The incidence of pharyngeal mucosal injury was smaller in the videolaryngoscope group than in the conventional group (14% vs. 52%; absolute difference, 38%; 95% CI 21%-55%; p < 0.001). CONCLUSIONS: Our study showed that in intubated critically ill patients required transesophageal echocardiogram, the use of videolaryngoscope resulted in higher successful insertion on the first attempt with lower rate of complications when compared with the conventional insertion technique. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04980976.


Assuntos
Laringoscópios , Laringoscopia , Humanos , Laringoscopia/efeitos adversos , Laringoscopia/métodos , Ecocardiografia Transesofagiana/efeitos adversos , Ecocardiografia Transesofagiana/métodos , Estado Terminal/terapia , Intubação Intratraqueal/efeitos adversos , Intubação Intratraqueal/métodos , Unidades de Terapia Intensiva
9.
Cardiovasc Diabetol ; 23(1): 1, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172989

RESUMO

BACKGROUND: Obesity has increased in recent years with consequences on diabetes and other comorbidities. Thus, 1 out of 3 diabetic patients suffers cardiovascular disease (CVD). The network among glucose, immune system, endothelium and epicardial fat has an important role on pro-inflammatory and thrombotic mechanisms of atherogenesis. Since semaglutide, long-acting glucagon like peptide 1- receptor agonist (GLP-1-RA), a glucose-lowering drug, reduces body weight, we aimed to study its effects on human epicardial fat (EAT), aortic endothelial cells and neutrophils as atherogenesis involved-cardiovascular cells. METHODS: EAT and subcutaneous fat (SAT) were collected from patients undergoing cardiac surgery. Differential glucose consumption and protein cargo of fat-released exosomes, after semaglutide or/and insulin treatment were analyzed by enzymatic and TripleTOF, respectively. Human neutrophils phenotype and their adhesion to aortic endothelial cells (HAEC) or angiogenesis were analyzed by flow cytometry and functional fluorescence analysis. Immune cells and plasma protein markers were determined by flow cytometry and Luminex-multiplex on patients before and after 6 months treatment with semaglutide. RESULTS: GLP-1 receptor was expressed on fat and neutrophils. Differential exosomes-protein cargo was identified on EAT explants after semaglutide treatment. This drug increased secretion of gelsolin, antithrombotic protein, by EAT, modulated CD11b on neutrophils, its migration and endothelial adhesion, induced by adiposity protein, FABP4, or a chemoattractant. Monocytes and neutrophils phenotype and plasma adiposity, stretch, mesothelial, fibrotic, and inflammatory markers on patients underwent semaglutide treatment for 6 months showed a 20% reduction with statistical significance on FABP4 levels and an 80% increase of neutrophils-CD88. CONCLUSION: Semaglutide increases endocrine activity of epicardial fat with antithrombotic properties. Moreover, this drug modulates the pro-inflammatory and atherogenic profile induced by the adiposity marker, FABP4, which is also reduced in patients after semaglutide treatment.


Assuntos
Aterosclerose , Diabetes Mellitus Tipo 2 , Humanos , Células Endoteliais/metabolismo , 60428 , Neutrófilos , Fibrinolíticos/uso terapêutico , Aterosclerose/metabolismo , Peptídeos Semelhantes ao Glucagon/farmacologia , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Obesidade/metabolismo , Glucose/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico
10.
Brain Cogn ; 175: 106130, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38219414

RESUMO

Evidence accumulates to show that semantic cognition requires, in addition to semantic representations, control processes that regulate the accessibility and use of semantic knowledge in a task- and time-appropriate fashion. Semantic control has been recently proposed to rely on a distributed network that includes the posterior temporal cortex. Along these lines, recent meta-analyses of neuroimaging data and studies with patients suffering from semantic aphasia have suggested that the left posterior middle temporal gyrus (pMTG) is critically involved whenever situational context must constrain semantic retrieval. In the present experiment, we used transcranial direct current stimulation over the left posterior temporal lobe in an attempt to interfere with semantic control while participants performed a DRM task, a procedure for inducing conceptually-based false recognition that is contingent on both activation and control processes. Paralleling findings with patients suffering from brain damage restricted to the temporoparietal cortex, anodal stimulation (relative to sham stimulation) resulted in increased false recognition but intact true recognition. These findings fit well with the idea that the left pMTG is a key component of a semantic control network, the alteration of which results in memory performance that is affected by the intrusion of contextually-inappropriate semantic information.


Assuntos
Memória Episódica , Estimulação Transcraniana por Corrente Contínua , Humanos , Semântica , Mapeamento Encefálico , Lobo Temporal/fisiologia , Imageamento por Ressonância Magnética
11.
Eur J Pharmacol ; 962: 176216, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38040081

RESUMO

BACKGROUND: The sequelae of myocardial infarction (MI) require specific pharmacological therapy to minimise the post-MI remodelling, which in many cases evolves into cardiovascular complications. The aim of this study was to analyse the effect of edoxaban, an oral anticoagulant, on cardiac recovery in a rat model of permanent coronary artery ligation. METHODS: An experimental method to assess the post-MI remodelling in rats for 4 weeks, based on cardiac magnetic resonance imaging (MRI) and final histological analysis of the hearts was performed. The influence of daily oral treatment with edoxaban (20 mg/kg/day) for 28 days post-MI was analysed in comparison to vehicle. RESULTS: In our model, edoxaban was shown to be safe and bleeding was observed in 1 of 10 animals. General physical recovery of the treated animals was shown by higher body weight recovery compared with non-treated animals (38.6 ± 2.9 vs. 29.9 ± 3.1 g, respectively, after 28 days). There was not a pronounced effect of edoxaban in post-MI cardiac remodelling, but mitigated fibrosis was observed by the reduced expression of vascular endothelial growth factor and tumour growth factor ß1 in the peri-infarct zone. CONCLUSIONS: Our analysis provided the experimental basis to support the feasibility of MRI to study cardiac function and characterise myocardial scarring in a rat model. Overall data suggested the safety of edoxaban in the model, and compared to placebo, it showed a better post-MI recovery, probably by reducing fibrosis of the heart. Further research on mid-term cardiac recovery with edoxaban after MI is justified.


Assuntos
Infarto do Miocárdio , Fator A de Crescimento do Endotélio Vascular , Ratos , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Miocárdio/metabolismo , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/tratamento farmacológico , Fibrose , Remodelação Ventricular
12.
J Cardiovasc Transl Res ; 17(1): 13-23, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37878196

RESUMO

The coexistence of heart failure (HF) and atrial fibrillation (AF) worsens the prognosis of patients. We aimed to study the inflammation, metabolism, adiposity, and fibrosis markers on epicardial and subcutaneous fat and blood, and their relationship with HF and AF. Samples from 185 patients undergoing cardiac surgery were collected. Levels of multi-markers on fat biopsies and plasma were analyzed. Patients were grouped by HF or AF presence. Plasma adiposity markers were increased in AF patients, while increased stretch markers correlated with HF. Patients with both AF and HF had higher ANP and GDF-15 levels. After excluding AF patients, plasma FABP4 was identified as the main HF predictor. Fat biopsies from AF patients showed an enhanced inflammatory profile. Higher levels of adiposity markers are associated with AF or HF, and higher stretch and fibrosis markers with combined AF and HF, suggesting a role of adiposity-fibrosis pathway in HF and AF coexistence.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/etiologia , Adiposidade , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/complicações , Fibrose , Biomarcadores
13.
J Thorac Dis ; 15(10): 5605-5612, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37969290

RESUMO

Background: Rapid deployment aortic valve replacement (RD-AVR) has been recently introduced with encouraging results. Outcomes of isolated RD-AVR include good hemodynamic profile, facilitation of minimally invasive techniques, and reduction of surgical times. However, role of this prosthesis in concomitant surgery is not well known. Methods: In 2016, we formed a registry to monitor the introduction of this prosthesis, RApid Deployment Aortic Replacement (RADAR). We aim to report mid-term outcomes focusing on patients who had RD-AVR combined with other surgical procedures. Results: Between July 2012 and February 2021, 370 patients were included in this registry (mean age, 75.8±8.0 years; 64.32% male; mean EuroSCORE II, 3.5±2.8). Of these, 128 (34.59%) had concomitant procedures including myocardial revascularization surgery in 69 patients (53.91%), surgery on the ascending aorta in 34 (26.56%), and procedures on other valves in 10 patients (7.81%). There were no significant differences between the isolated AVR and concomitant AVR groups in postoperative complications, in-hospital mortality (4.72% vs. 3.32%, P=0.524), or hemodynamic behavior of these prostheses. Three-year survival was 83.73% and 89.89% in the isolated and concomitant AVR group respectively. There was no difference in survival between the two groups (log-rank test, P=0.4124). Conclusions: Our results support the safety and efficacy of the Edwards INTUITY valve system even in complex aortic valve disease with additional cardiac procedures. RD-AVR could become a useful tool for concomitant surgeries where surgical times are expected to be prolonged.

14.
Braz J Otorhinolaryngol ; 90(2): 101360, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38035470

RESUMO

OBJECTIVES: To analyze the clinical utility of a clinical risk scale to predict the need for advanced airway management in patients with deep neck abscess. METHODS: Observational, analytical, cross-sectional study. Patients over 18 years old, both genders, with surgical management of a deep neck abscess, between January 1st, 2015 to December 31th, 2021, who were applied the clinical risk scale (https://7-414-5-19.shinyapps.io/ClinicalRiskScore/). The sensitivity, specificity, and predictive values of the scale were calculated based on the identified clinical outcomes. A p<0.05 was considered significant. RESULTS: A sample of 213 patients was obtained, 121 (56.8%) men, of whom 50 (23.5%) required advanced airway management. Dyspnea was the variable with the most statistical weight in our study, (p=0.001) as well as the multiple spaces involvement, (p=0.001) the presence of air corpuscles, (p=0.001) compromise of the retropharyngeal space (p=0.001) and age greater than 55 years (p=0.001). Taking these data into account, were found for the clinical risk scale a sensitivity of 97% and a specificity of 65% (p=0.001, 95% CI 0.856-0.984). CONCLUSIONS: The clinical risk scale developed to predict advanced airway management in patients with a diagnosis of deep neck abscess may be applicable in our environment with high sensitivity and specificity. LEVEL OF EVIDENCE: IV.

15.
Polymers (Basel) ; 15(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37835964

RESUMO

The use of recycled polypropylene in industry to reduce environmental impact is increasing. Design for manufacturing and process simulation is a key stage in the development of plastic parts. Traditionally, a trial-and-error methodology is followed to eliminate uncertainties regarding geometry and process. A new proposal is presented, combining simulation with the design of experiments and creating prediction models for seven different process and part quality output features. These models are used to optimize the design without developing additional time-consuming simulations. The study aims to compare the precision and correlation of these models. The methods used are linear regression and artificial neural network (ANN) fitting. A wide range of eight injection parameters and geometry variations are used as inputs. The predictability of nonlinear behavior and compensatory effects due to the complex relationships between this wide set of parameter combinations is analyzed further in the state of the art. Results show that only Back Propagation Neural Networks (BPNN) are suitable for correlating all quality features in a single formula. The use of prediction models accelerates the optimization of part design, applying multiple criteria to support decision-making. The methodology is applied to the design of a plastic support for induction hobs. Furthermore, this methodology has demonstrated that a weight reduction of 27% is feasible. However, it is necessary to combine process parameters that differ from the standard ones with a non-uniform thickness distribution so that the remaining injection parameters, material properties, and dimensions fall within tolerances.

16.
Polymers (Basel) ; 15(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37836059

RESUMO

Thermoplastic polyurethanes (TPUs) are remarkably versatile polymers due to the wide range of raw materials available for their synthesis, resulting in physicochemical characteristics that can be tailored according to the specific requirements of their final applications. In this study, a renewable bio-based polyol obtained from soybean oil is used for the synthesis of TPU via reactive extrusion, and the influence of the bio-based polyol on the multi-phase structure and properties of the TPU is studied. As raw materials, 4,4'-diphenylmethane (MDI), 1,4-butanediol, a fossil-based polyester polyol, and a bio-based polyol are used. The fossil-based to soybean-based polyol ratios studied are 100/0, 99/1, 95/5, 90/10, 80/20, and 50/50% by weight, respectively. The TPUs were characterized by size exclusion chromatography (SEC), gel content analysis, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), dynamic mechanical analysis (DMA), and contact angle measurements. The results reveal that incorporating the renewable polyol enhances the compatibility between the rigid and flexible segments of the TPU. However, due to its high functionality, the addition of soybean-based polyol can promote cross-linking. This phenomenon reduces the density of hydrogen bonds within the material, also reducing polarity and restricting macromolecular mobility, as corroborated by higher glass transition temperature (Tg) values. Remarkably, the addition of small amounts of the bio-based polyol (up to 5 wt.% of the total polyol content) results in high-molecular-weight TPUs with lower polarity, combined with suitable processability and mechanical properties, thus broadening the range of applications and improving their sustainability.

17.
Nature ; 622(7983): 471-475, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37758953

RESUMO

Resonant oscillators with stable frequencies and large quality factors help us to keep track of time with high precision. Examples range from quartz crystal oscillators in wristwatches to atomic oscillators in atomic clocks, which are, at present, our most precise time measurement devices1. The search for more stable and convenient reference oscillators is continuing2-6. Nuclear oscillators are better than atomic oscillators because of their naturally higher quality factors and higher resilience against external perturbations7-9. One of the most promising cases is an ultra-narrow nuclear resonance transition in 45Sc between the ground state and the 12.4-keV isomeric state with a long lifetime of 0.47 s (ref. 10). The scientific potential of 45Sc was realized long ago, but applications require 45Sc resonant excitation, which in turn requires accelerator-driven, high-brightness X-ray sources11 that have become available only recently. Here we report on resonant X-ray excitation of the 45Sc isomeric state by irradiation of Sc-metal foil with 12.4-keV photon pulses from a state-of-the-art X-ray free-electron laser and subsequent detection of nuclear decay products. Simultaneously, the transition energy was determined as [Formula: see text] with an uncertainty that is two orders of magnitude smaller than the previously known values. These advancements enable the application of this isomer in extreme metrology, nuclear clock technology, ultra-high-precision spectroscopy and similar applications.

18.
Nutrients ; 15(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37630733

RESUMO

Protein supplements (PS) are trendy foods, especially those made from whey. In addition to providing protein, these products are a source of metals, providing essential elements (Na, K, Mg, Ca, Mo, Mn, Fe, Co, Cu, and Zn) and other potentially toxic elements (Al, B, Sr, V Ba, and Ni). In this study, 47 whey PS samples were analyzed for mineral elements by ICP-OES, and their dietary exposures were assessed for three consumption scenarios. Elements found in higher concentrations were K (4689.10 mg/kg) and Ca (3811.27 mg/kg). The intake of 30 g PS (average recommended amount/day) provides about 20% of the established reference value (NRI) for Cr (18.30% for men and 25.63% for women) and Mo (26.99%). In a high daily consumption scenario (100 g PS/day) and when the maximum concentrations are considered, Cr, Zn, Fe, Mo, and Mg dietary intakes of these metals exceed the daily recommended intakes and could pose a risk. The daily intake of 30, 60, and 100 g of whey PS for 25 years does not pose a health risk since the hazard index (HI) is less than one in these consumption scenarios, and the essential elements contributing most to HI are Co, followed by Mo and Cr. It is recommended to improve the information to the consumers of these new products. Furthermore, to help in the management and prevention of these potential health risks, it would be advisable to improve the regulation of these dietary supplements and their labeling.


Assuntos
Metais , Soro do Leite , Masculino , Feminino , Humanos , Proteínas do Soro do Leite , Exposição Dietética , Suplementos Nutricionais
19.
Children (Basel) ; 10(5)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37238440

RESUMO

Spinal Muscular Atrophy (SMA) type I has classically presented extremely severe clinical features. New pharmacological treatments have led to a new phenotype of SMA. The aim of this study was to describe the current health and functional status of children with SMA. A cross-sectional study was conducted based on the STROBE guidelines. Patient questionnaires and standardized tools were used. A descriptive analysis was conducted establishing the proportions of subjects for each of the characteristics of interest. In total, 51 genetically confirmed SMA type I subjects were included. Fifty-seven percent received oral feeding, 33% received tube feeding and 10% combined both. Moreover, 21.6% had tracheostomies, and 9.8% needed more than 16 h/d ventilatory support. Regarding orthopedic status, 66.7% had scoliosis, and 68.6% had hip subluxation or dislocation. Up to 67% were able to sit independently, 23.5% walked with support and one child walked independently. Current SMA type I is a different entity from the classic phenotype but also from types II and III. In addition, no differences were found between SMA type I subgroups. These findings may enable the professionals involved in the care of these patients to improve their interventions in terms of prevention and rehabilitation measures for these children.

20.
Polymers (Basel) ; 15(10)2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37242875

RESUMO

Hybrid materials have been studied because in these materials the properties of organic components, such as elasticity and biodegradability, could be combined with the properties of inorganic components, such as good biological response, thereby transforming them into a single material with improved properties. In this work, Class I hybrid materials based on polyester-urea-urethanes and titania were obtained using the modified sol-gel method. This was corroborated using the FT-IR and Raman techniques which highlighted the formation of hydrogen bonds and the presence of Ti-OH groups in the hybrid materials. In addition, the mechanical and thermal properties and degradability were measured using techniques, such as Vickers hardness, TGA, DSC, and hydrolytic degradation; these properties could be tailored according to hybridization between both organic and inorganic components. The results show that Vickers hardness increased by 20% in hybrid materials as compared to polymers; also, the surface hydrophilicity increases in the hybrid materials, improving their cell viability. Furthermore, cytotoxicity in vitro test was carried out using osteoblast cells for intended biomedical applications and they showed non-cytotoxic behavior.

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